1,445 results on '"Absolute difference"'
Search Results
2. The impact of perceived absolute differences between student international mindset and university internationalization on student learning engagement: the mediating role of market orientation.
- Author
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Peng, Michael Yao-Ping
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MARKET orientation ,STUDENT aspirations ,STUDENT engagement ,FOREIGN students ,COLLEGE students ,RELATIONSHIP marketing ,ACADEMIC degrees - Abstract
This research examines the interplay between students' international mindset, the degree of college internationalization, market orientation, and learning engagement within higher education. Addressing a notable gap in existing literature, this study delves into how these elements collectively impact student success in an increasingly globalized context. Data were gathered from six universities, encompassing a sample of 1,633 participants. Findings revealed a positive correlation between market orientation and learning engagement, as well as between international mindset and learning engagement, though the latter was less pronounced. Interestingly, while internationalization did not show a significant direct correlation with learning engagement, it exhibited a robust relationship with market orientation. Moreover, the disparity in perceptions of international mindset and actual college internationalization did not significantly influence learning engagement but had a negative association with market orientation. These insights are pivotal for universities aiming to adeptly prepare students for the global landscape. By understanding the nuanced relationships among these factors, educational institutions can devise strategies that resonate with student aspirations and needs, thereby enhancing engagement, satisfaction, and academic achievement. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Multimodal Biometrics Authentication in Healthcare Using Improved Convolution Deep Learning Model.
- Author
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Balaji, S and Rahamathunnisa, U
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BIOMETRIC identification , *DEEP learning , *MULTIMODAL user interfaces , *CONVOLUTIONAL neural networks , *PYTHON programming language , *RELIABILITY in engineering , *MEDICAL care - Abstract
In healthcare applications, biometric authentication is crucial in managing patient credential details. The limited usage of biometric traits causes personal details theft, treatment hacking, and payment hijacking. Multimodal biometrics should incorporate into the healthcare system to maintain security and privacy in healthcare applications. Previous methods ensure authentication and security consume high computation complexity and fail to maintain system reliability and scalability. Therefore, in this work, an improved convolution deep learning model (ICDLM) is applied to manage the patient traits in the healthcare center. Initially, Experimentation is conducted with SWAN DATASET, which consists of face, voice, and periocular biometric features. The biometric characteristics are investigated according to the super point convolution neural model. The model analyzes the trait descriptors and interest points to identify the patterns. The extracted patterns are utilized to match the patient while accessing the information in healthcare applications. This process uses template pattern matching (TPM), which minimizes the absolute difference while authenticating the users. The system's efficiency implemented using Python and excellency is compared with traditional approaches. The system attains 98.31% and 98.67% accuracy on the number of users and attempts with a minimum false identification rate of 0.0125 and 0.0128 for several users and attempts. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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4. Methodological Issues When Interpreting Changes in Social Phenomena Over Time: Perceptions of Relative Difference, Absolute Difference, and Time Distance.
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Prevodnik, Katja and Vehovar, Vasja
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SOCIAL facts , *SOCIAL change , *TIME perception , *DEPTH perception , *TIME perspective , *OFFICES - Abstract
When comparing social science phenomena through a time perspective, absolute and relative difference (RD) are the two typical presentation formats used to communicate interpretations to the audience, while time distance (TD) is the least frequently used of such formats. This article argues that the chosen presentation format is extremely important because the various formats suggest different substantive interpretations. To elaborate upon this issue, researchers from the National Statistical Office, National Health Institute, and general academia were invited to participate in an experiment with alternative presentation formats that describe changes in certain social science phenomena over time. The results revealed a prevailing tendency of respondents to rely on interpretations related to absolute differences, which was additionally reinforced with graphical presentation formats. Therefore, whenever RD or TD is more proper for substantive interpretations, the corresponding presentation format must be designed with special attention. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
5. Change detection with cross enhancement of high‐ and low‐level change‐related features
- Author
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Rui Huang, Yan Xing, Mo Zhou, and Ruofei Wang
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absolute difference ,change detection ,change‐related feature ,cross feature enhancement ,Photography ,TR1-1050 ,Computer software ,QA76.75-76.765 - Abstract
Abstract Change detection (CD) is a fundamental yet challenging problem, which aims at detecting changed object in two observations. Recent CD methods are designed based on the off‐the‐shelf semantic segmentation network architectures, which is not optimal for extracting and using change‐related features. In this paper, a novel CD network architecture is proposed, including change‐related feature extraction, cross feature enhancement, and multi‐level supervision. Absolute difference of the features of different convolutional layers is first computed from a Unet‐like network for two observations. The features are partitioned into high‐ and low‐level features according to their functionalities. Then the high‐ and low‐level features are recurrently refined by cross feature enhancement to increase the representational ability of the features. The network learns change‐related features with multi‐level supervisions. The final CD result can be obtained by fusing multiple predictions. Experimental results on three CD benchmark datasets indicate the superiority of the authors' method when compared with six state‐of‐the‐art deep learning‐based CD methods.
- Published
- 2021
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- View/download PDF
6. La posición topológica de Plotino y el comienzo metafísico de la philo-SOPHIA medieval.
- Author
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MARTIN DE BLASSI, FERNANDO G.
- Subjects
ORIGINALITY ,METAPHYSICS ,MEDIEVAL philosophy ,HISTORIOGRAPHY ,MEDIEVALISM - Abstract
Copyright of Scripta Mediaevalia is the property of Universidad Nacional de Cuyo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2022
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- View/download PDF
7. Dynamic programming with adaptive and self-adjusting penalty for real-time accurate stereo matching.
- Author
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Hallek, Mohamed, Boukamcha, Hamdi, Mtibaa, Abdellatif, and Atri, Mohamed
- Abstract
Dense disparity map extraction is one of the most active research areas in computer vision. It tries to recover three-dimensional information from a stereo image pair. A large variety of algorithms has been developed to solve stereo matching problems. This paper proposes a new stereo matching algorithm, capable of generating the disparity map in real-time and with high accuracy. A novel stereo matching approach is based on per-pixel difference adjustment for the absolute differences, gradient matching and rank transform. The selected cost metrics are aggregated using guided filter. The disparity calculation is performed using dynamic programming with self-adjusting and adaptive penalties to improve disparity map accuracy. Our approach exploits mean-shift image segmentation and refinement technique to reach higher accuracy. In addition, a parallel high-performance graphics hardware based on Compute Unified Device Architecture is used to implement this method. Our algorithm runs at 36 frames per second on 640 × 480 video with 64 disparity levels. Over 707 million disparity evaluations per second (MDE/s) are achieved in our current implementation. In terms of accuracy and runtime, our algorithm ranks the third place on Middlebury stereo benchmark in quarter resolution up to the submitting. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
8. An Absolute Differences K-Means Clustering Approach on Determining Intervals to Optimize Fuzzy Time Series Markov Chain Model.
- Author
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Alwarid, Ahmad and Sihabuddin, Agus
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TIME series analysis ,STANDARD deviations ,MARKOV processes ,K-means clustering - Abstract
Fuzzy Time Series models have been developed in various ways, one of which is determining the intervals. Several methods were applied to determine the intervals, but the performances are still not optimal. This paper proposes a new approach that uses a combination of Absolute Differences and K-means Clustering in the Fuzzy Time Series Markov Chain model. K-means Clustering made the interval more flexible and compact based on the data it clustered. In addition, Absolute Differences was used as the based method to define how many intervals to be made. This study used Taiwan Capitalization Weighted Stock Index (TAIEX) as benchmark data to evaluate the proposed method, which produced an average Mean Absolute Percentage Error (MAPE) value of 0.42, and an average Root Mean Squared Error (RMSE) value of 51.09 for the test data. The proposed method outperformed other compared researches at the end of this paper in terms of prediction accuracy. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
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9. Understanding Wealth Inequalities in Education Access in Urbanizing Sub-Saharan Africa
- Author
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Maurice Mutisya, John Munyui Muchira, and Benta A. Abuya
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inequaility ,urban poor ,demographic and health survey (DHS) ,absolute difference ,relative concentration index ,rate ratio ,Education (General) ,L7-991 - Abstract
Introduction: Urbanization is a double-edged sword, while it is transforming the world, it is also creating spaces that pose threats to its benefits. In sub-Saharan Africa, urbanization is occurring amidst slowed economic growth and into spaces that are already strained. This is resulting in the growth of urban poverty and possibly increasing inequalities. It is thus imperative to understand the effects of urbanization in realizing inclusive and equitable education for all.Objective: We examine inequalities in enrolment of schooling going children aged 6–17 years living in urban areas using the latest Demographic and Health Surveys data from 24 SSA countries.Methods: We utilize three measures of inequality: Rate difference, rate ratio, and relative concentration index to examine inequalities in education access. Using wealth status as the key inequality indicator, we compute and compare school enrollment of children living in urban poor households with that of those living in urban rich households for each measure of inequality. Where appropriate, we stratify the results by country, age, and gender.Results: The results show high levels of inequalities in education access in urban settings. Across all the measures of inequality, in most countries, children from urban poor households were significantly less likely to be in school compared to those from the richest ranked households. The degree of inequality varied considerably between countries and the age groups. Among children aged 6–11 years, Tanzania, Burundi, Nigeria, and Uganda had the highest degree of inequality favouring the urban rich. We also find intriguing results in few countries such as Ethiopia, Benin, Senegal and Mali, which the urban poor had, better school enrolments than the urban rich. We do not find a clear pattern to suggest girls from poor households are overly disadvantaged than boys from similar households.Conclusion: Our study shows a high level of inequalities in education access in an urban setting, with children age in urban poor settings hugely disadvantaged. There is a need for strategic efforts in terms of deliberate interventions and policy frameworks to combat the apparent inequalities that disadvantage children from poor families from accessing education.
- Published
- 2021
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10. Change detection with cross enhancement of high‐ and low‐level change‐related features.
- Author
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Huang, Rui, Xing, Yan, Zhou, Mo, and Wang, Ruofei
- Subjects
- *
COMPUTER vision , *IMAGE enhancement (Imaging systems) , *DIGITAL image processing , *CONVOLUTIONAL neural networks , *DEEP learning - Abstract
Change detection (CD) is a fundamental yet challenging problem, which aims at detecting changed object in two observations. Recent CD methods are designed based on the off‐the‐shelf semantic segmentation network architectures, which is not optimal for extracting and using change‐related features. In this paper, a novel CD network architecture is proposed, including change‐related feature extraction, cross feature enhancement, and multi‐level supervision. Absolute difference of the features of different convolutional layers is first computed from a Unet‐like network for two observations. The features are partitioned into high‐ and low‐level features according to their functionalities. Then the high‐ and low‐level features are recurrently refined by cross feature enhancement to increase the representational ability of the features. The network learns change‐related features with multi‐level supervisions. The final CD result can be obtained by fusing multiple predictions. Experimental results on three CD benchmark datasets indicate the superiority of the authors' method when compared with six state‐of‐the‐art deep learning‐based CD methods. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
11. Automatic Text Recognition Using Difference Ratio
- Author
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Anwar, Shamama, Howlett, Robert James, Series Editor, Jain, Lakhmi C., Series Editor, Satapathy, Suresh Chandra, editor, Bhateja, Vikrant, editor, and Das, Swagatam, editor
- Published
- 2018
- Full Text
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12. Video Summarization for Surveillance System Using key-frame Extraction based on Cluster.
- Author
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Awadh, Amal H. and Taher, Hazeem B.
- Subjects
VIDEOS ,SURVEILLANCE detection ,WEB browsing ,HISTOGRAMS ,DATA analysis - Abstract
The amount of data has grown in recent years due to the use of a vast number of videos, which requires time to access them in addition to the difficulty of browsing and retrieving the video content. To fix this issue, it was proposed that the videos be summarized for easy access and that the content of the videos is browsed easier. The primary objective of the video summary is to provide a simple description of the video by removing the redundancy and extracting keyframes from the video. This paper will clarify the four ways that are using to summing up the video based on the keyframe extraction. In frames extraction, the first two methods rely on the threshold value, while the second two methods rely on clustering to extract the keyframes. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
13. A critical analysis of the noninferiority design of the TALENT trial
- Author
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S. Saha, P. Kerkar, and N.J. Gogtay
- Subjects
TALENT trial ,Absolute difference ,Relative risk ,Noninferiority margin ,Sample size ,Surgery ,RD1-811 ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
In recent years, regulatory approval of stents has been based on studies that have a noninferiority design, which has its own inherent complexities. We critically appraise in this article, the TALENT trial that established the noninferiority of the Indian-manufactured Supraflex stent (a third-generation, sirolimus-eluting stent with an ultrathin strut thickness) compared with the Xience stent (an internationally available, everolimus-eluting stent with a thicker strut) for a device-oriented composite end point at the end of 12 months. Our analysis shows that if the risk ratio rather than absolute risk difference was used to calculate the noninferiority margin, we would obtain a value of 1.48 for the risk ratio. Supraflex would then be noninferior to Xience by 0.92 [95% confidence interval (CI) = 0.59 to 1.47]. The upper bound of the 95% CI of 1.47 is dangerously close to 1.48, indicating that the TALENT trial would just about manage to prove noninferiority.
- Published
- 2020
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14. Method for Computing Dense Optical Flow on FPGA in Real Time
- Author
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Alexander V. Bratulin, Mikhail B. Nikiforov, Pavel V. Belyakov, and Yevgeny Y. Kholopov
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optical flow ,fpga ,criterion function ,motion detection ,absolute difference ,Electronic computers. Computer science ,QA75.5-76.95 - Abstract
One of the most actual problems in the technical vision systems is the problem of objects detection and selection in the field of the image sensor view. Applications of objects automatic detection and object allocation technologies include search and rescue tasks, space monitoring of the Earth, traffic analysis, air traffic control, etc. Objects can be stationary and moving. The movement in the video can be formalized in a term such as optical flow. Optical flow is the basic tool for processing and analyzing video sequences, and its calculation is the most common approach to the detection of moving objects. The article describes the features of the hardware implementation of the FPGA method for calculating the dense optical flow on high-definition video. The developed method is based on the correlation-extreme algorithm for finding the minimum sum of absolute differences in the brightness of the pixels of the windows in the vicinity of the current point of neighboring frames of the video. A detailed description of the main stages of this algorithm is given. The principle of parallelization and pipelization, which allows us to minimize the amount of calculations due to the reuse of intermediate results obtained in the previous steps, is considered. The described approach allows us to calculate the optical flow for each pixel at the rate of input video. The hardware implementation cost of the method on the Xilinx Zynq Ultra Scale + FPGA, which is part of the Xilinx Zynq Ultra Scale + MPSoC ZCU102 Evaluation Kit, is considered.
- Published
- 2019
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15. Comparison of the fully penetrating well drawdown in leaky aquifers between fiite and infiite radius of inflence under steady-state pumping conditions
- Author
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Mihael Brenčič
- Subjects
leaky aquifer ,groundwater drawdown ,relative difference ,absolute difference ,modifid Bessel function of zero oder ,Hantush integral ,Geology ,QE1-996.5 - Abstract
In the paper theoretical derivation of steady state groundwater well pumping from leaky aquifers with infiite and fiite radius of inflence are presented. Based on the extensive literature review following mainly Jacob and Hantush work equations were derived from the cylindrical Bessel partial differential equation and results expressed in the combination of modifid Bessel functions of zero order of the fist and the second kind (I0, K0). We have shown that equation for steady state well pumping in the infiite aquifer is infiite limit of Hantush integral. Mathematical characteristics of solutions for infiite and fiite radius of well inflence were combined in the way that they can be represented as relative and absolute differences of drawdowns of each model. In the case when available data do not allow us to make a decision on the type of the radius of inflence of the pumping well, they can help us in the interpretation of various errors due to application of different analytical models of pumping test.
- Published
- 2018
- Full Text
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16. A Psicanálise e os paradoxos da política da diferença.
- Author
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Alberti, Sonia, Jorge, Marco Antonio Coutinho, and Caldas, Heloisa
- Abstract
Copyright of Trivium (2176-4891) is the property of Mestrado Profissional em Psicanalise, Saude e Sociedade da Universidade Veiga de Almeida and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2021
- Full Text
- View/download PDF
17. MPA‐Net: multi‐path attention stereo matching network.
- Author
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Sang, Haiwei, Yang, Zuliu, Yang, Xiaowei, and Zhao, Yong
- Abstract
A novel learning‐based end‐to‐end network for stereo matching, named Multi‐path Attention Stereo Matching (MPA‐Net), is introduced in this study. Different from existing methods, the multi‐path attention aggregation module is designed firstly, named MPA, which is a unified structure using three different parallel layers with a respective attention mechanism to extract the multi‐scale informational features. Secondly, the method of cost volume construction, which differs from the traditional stereo matching methods, is extended. And then, the absolute difference between two input features is calculated. Furthermore, a u‐shaped structure with 3D attention gate is selected as the encoder‐decoder module. Specifically, the module is used to fuse the encoding features to their corresponding decoding features under the supervision of the authors' attention gate with skip‐connection, and thus exploit more significant information for matching cost regularisation and disparity prediction. Finally, specific experiments are conducted to evaluate their network on SceneFlow, KITTI2012 and KITTI2015 data sets. The results show that their method achieves a better improvement in disparity maps prediction compared with some existing state‐of‐the‐art methods on KITTI benchmark. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
18. Change detection with absolute difference of multiscale deep features.
- Author
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Huang, Rui, Zhou, Mo, Zhao, Qiang, and Zou, Yaobin
- Subjects
- *
DEEP learning - Abstract
Most of the previous change detection methods are designed based on the difference of two images. However, directly using intensity or the features to generate difference image may be easily affected by the illumination and camera pose variations. In this paper, we show that accurate change detection results can be obtained by fusing the absolute difference of multiscale deep features of the reference and query images. Specifically, we build a change detection network, which computes absolute difference of the multiscale deep features of image pairs and learns adaptive features for change detection. The proposed network is based on off-the-shelf CNNs, whose convolutional layer blocks are used as feature extracting modules to extract multiscale deep features. We devise intra and cross encoding modules. The intra encoding modules are used for learning change related features from extracted features. These features are used for generating absolute difference features (ADFs). By progressively fusing the ADFs from high to low layers with cross encoding modules, we obtain full resolution of change detection result. Extensive experiments on three change detection benchmark datasets validate the superiority and effectiveness of the proposed method over the state-of-the-art change detection methods. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
19. Movement Detection Using LabVIEW by Analysis of Real-Time Video
- Author
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Sumalatha, D. V., Kumar, A. V. Ravi, Kacprzyk, Janusz, Series editor, Satapathy, Suresh Chandra, editor, Raju, K. Srujan, editor, Mandal, Jyotsna Kumar, editor, and Bhateja, Vikrant, editor
- Published
- 2016
- Full Text
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20. Systematic Derivation of Bounds and Glue Constraints for Time-Series Constraints
- Author
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Arafailova, Ekaterina, Beldiceanu, Nicolas, Carlsson, Mats, Flener, Pierre, Francisco Rodríguez, María Andreína, Pearson, Justin, Simonis, Helmut, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Doug, Series editor, Weikum, Gerhard, Series editor, and Rueher, Michel, editor
- Published
- 2016
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21. Hardware Implementation of Fuzzy Logic in Early Days of 'Fuzzy' Era
- Author
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Yamakawa, Takeshi, Miki, Tsutomu, Kacprzyk, Janusz, Series editor, Magdalena, Luis, editor, Verdegay, Jose Luis, editor, and Esteva, Francesc, editor
- Published
- 2015
- Full Text
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22. Power chains as an alternative to steel-wire ligatures in temporary maxillomandibular fixation
- Author
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L.J. van Ewijk, Alfred G. Becking, T.C.T. van Riet, I.G.H. van der Tol, J.P.T.F. Ho, Oral and Maxillofacial Surgery / Oral Pathology, AMS - Tissue Function & Regeneration, Orthodontics, Maxillofacial Surgery (AMC + VUmc), Graduate School, Oral and Maxillofacial Surgery, and Other Research
- Subjects
medicine.medical_treatment ,Statistical difference ,Orthognathic surgery ,Maxillomandibular fixation ,Pilot Projects ,Absolute difference ,Application time ,mandibular osteotomy ,Mandibular osteotomy ,Humans ,Medicine ,Prospective Studies ,Dental Implants ,Orthodontics ,business.industry ,maxillomandibular fixation ,orthognathic surgery ,Significant difference ,technology, industry, and agriculture ,Maxillary Osteotomy ,Jaw Fixation Techniques ,Cross-Sectional Studies ,Otorhinolaryngology ,Steel ,Surgery ,maxillary osteotomy ,Oral Surgery ,business ,orthodontics - Abstract
The aim of this study was to compare two techniques for temporary intraoperative maxillomandibular fixation (TIO-MMF) during orthognathic surgery: steel-wire ligatures versus power chains. Patients undergoing orthognathic surgery between October 2019 and March 2020 were included in a prospective cross-sectional study conducted in three participating hospitals. Data were collected using a standardized measurement form. A total of 44 patients were included, in whom TIO-MMF was applied 79 times. A statistically significant difference in intraoperative loss of stability of the segment relationship was found between steel-wire ligatures (11.4%) and power chains (0%). The mean application time of TIO-MMF differed significantly between steel-wire ligatures (99 seconds) and power chains (157 seconds) (P < 0.001). There was no statistical difference in occurrence of adverse events between the two techniques. This study found that the application of TIO-MMF with power chains is more stable compared to steel-wire ligatures. Steel-wire ligatures were significantly faster to apply, although the absolute difference (less than 1 minute) was small. Other possible advantages of the proposed technique are discussed. The results of this study suggest that power chains for the application of TIO-MMF in orthognathic surgery are a valuable alternative to steel-wire ligatures.
- Published
- 2022
23. Quantitative prediction of oil saturation of unconsolidated sandstone reservoir based on time-lapse seismic "relative difference method": Taking Zeta oil field in West Africa as an example.
- Author
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LU, Hongmei, XU, Hai, WO, Yujin, and GU, Ning
- Abstract
In view of the disadvantage that the absolute difference of time-lapse seismic (the difference between monitoring data and base data) is not only related to the change of oil saturation, but also closely related to the thickness of reservoir, a time-lapse seismic "relative difference method" (the ratio of monitoring data to base data) not affected by the thickness of reservoir but only related to the change of fluid saturation, is proposed through seismic forward modeling after fluid displacement simulation. Given the same change of fluid saturation, the absolute difference of time-lapse seismic conforms to the law of "tuning effect" and seismic reflection of "thin bed", and the remaining oil prediction method based on absolute difference of time-lapse seismic is only applicable to the reservoirs with uniform thickness smaller than the tuning thickness or with thickness greater than the tuning thickness. The relative difference of time-lapse seismic is not affected by reservoir thickness, but only related to the change of fluid saturation. It is applicable to all the deep-sea unconsolidated sandstone reservoirs which can exclude the effect of pressure, temperature, pore type and porosity on seismic. Therefore, the relation between the relative difference of time-lapse seismic and the change of fluid saturation, which is obtained from seismic forward modeling after Gassmann fluid displacement simulation, can be used to quantitatively predict the change of reservoir water saturation and then the distribution of the remaining oil. The application of this method in deep sea Zeta oil field in west Africa shows that it is reasonable and effective. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
24. Measuring Rectal Cancer Tumor Height: Concordance Between Clinical Examination and MRI
- Author
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Shuai Chen, Linda M. Farkas, and Shannon M. Navarro
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medicine.medical_specialty ,Rectal Neoplasms ,business.industry ,Colorectal cancer ,Concordance ,Rectum ,Gastroenterology ,Cancer ,Clinical exam ,General Medicine ,Absolute difference ,medicine.disease ,Single Center ,Magnetic Resonance Imaging ,Article ,Pelvis ,Clinical trial ,medicine.anatomical_structure ,medicine ,Humans ,Radiology ,business ,Retrospective Studies - Abstract
Rectal cancer is categorized into categories on the basis of tumor height measurements. Tumor height is used to guide initial treatment and determines the eligibility for clinical trials.This study aimed to determine the concordance between tumor heights measured by MRI and by clinical examination.This was an institutional review board-approved retrospective analysis of MRI and the clinical measurements of tumor height.This study was conducted at a single university center that was accredited by the Commission on Cancer National Accreditation Program for Rectal Cancer.Ninety-five patients who were treated between 2015 and 2019 and who had an MRI and clinical evaluation were included.The mean difference of tumor height between MRI and clinical examination was calculated. Secondary outcomes were to assess whether position in the rectum, age, BMI, or sex would affect the difference and how the measurements would change eligibility for rectal cancer trials.Tumor height measurement by MRI and clinical examination had a good correlation, with r = 0.89 and p0.001. The mean absolute difference of measurement of tumor height was 1.56 cm. Higher tumors had a larger absolute difference between measurements. Body mass index was significantly associated with the difference in measurements. The discordance in measurements led to a change in eligibility for clinical trials for 38.9% of patients. Clinical trial eligibility was not significantly associated with tumor height category, sex, or patient age.This study was conducted at a single center with retrospective methodology.Although MRI and clinical measurements showed a strong correlation, nearly 40% of our patients had a change in clinical trial eligibility depending on measurement modality. We suggest that trial investigators be consistent in establishing measurement technique as their inclusion criterion. See Video Abstract at http://links.lww.com/DCR/B756.ANTECEDENTES:El cáncer de recto se clasifica en categorías basadas en las mediciones de la altura del tumor. La altura del tumor se usa para guiar el tratamiento inicial y determina la elegibilidad para los ensayos clínicos.OBJETIVO:Determinar la concordancia entre la altura de los tumores medida por resonancia magnética (RMN) y por examen clínico.DISEÑO:Este fue un análisis retrospectivo aprobado por el IRB de la resonancia magnética y las mediciones clínicas de la altura del tumor.AJUSTE:Esto se llevó a cabo en un único centro universitario que fue acreditado por el Programa Nacional de Acreditación del Cáncer de Recto de la Comisión de Cáncer.PACIENTE:Se incluyeron 95 pacientes que fueron atendidos entre 2015 y 2019 y que tuvieron una resonancia magnética y evaluación clínica.PRINCIPALES MEDIDAS DE RESULTADOS:Se calculó la diferencia media de la altura del tumor entre la resonancia magnética y el examen clínico. Los resultados secundarios fueron evaluar si la posición en el recto, la edad, el índice de masa corporal (IMC) o el sexo afectarían la diferencia y cómo las mediciones cambiarían la elegibilidad para los ensayos de cáncer de recto.RESULTADOS:La medición de la altura del tumor por resonancia magnética y el examen clínico tuvo una buena correlación con r = 0,89 y p0,001. La diferencia absoluta media de medición de la altura del tumor fue de 1,56 cm. Los tumores más altos tenían una diferencia absoluta más grande entre las mediciones. El IMC se asoció significativamente con la diferencia en las mediciones. La discordancia en las mediciones llevó a un cambio en la elegibilidad para los ensayos clínicos para el 38,9% de los pacientes. La elegibilidad para ensayos clínicos no se asoció significativamente con la categoría de altura del tumor, el sexo o la edad del paciente.LIMITACIONES:Se realizó en un solo centro con metodología retrospectiva.CONCLUSIONES:Aunque la resonancia magnética y las mediciones clínicas mostraron una fuerte correlación, casi el 40% de nuestros pacientes tuvieron un cambio en la elegibilidad para los ensayos clínicos según la modalidad de medición. Sugerimos que los investigadores del ensayo sean coherentes al establecer la técnica de medición como criterio de inclusión. Consulte Video Resumen en http://links.lww.com/DCR/B756.
- Published
- 2022
25. Evaluation of the Vegetation-Index-Based Dimidiate Pixel Model for Fractional Vegetation Cover Estimation
- Author
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Guangjian Yan, Yiyi Tong, Haojing Chi, Xihan Mu, Kai Yan, Si Gao, Wanjuan Song, and Jianbo Qi
- Subjects
Endmember ,Pixel ,Solar zenith angle ,Enhanced vegetation index ,Absolute difference ,Normalized Difference Vegetation Index ,FEV1/FVC ratio ,medicine ,General Earth and Planetary Sciences ,Electrical and Electronic Engineering ,medicine.symptom ,Vegetation (pathology) ,Remote sensing ,Mathematics - Abstract
Remote sensing estimation based on the dimidiate pixel model (DPM) using vegetation indices (VIs) is a common approach for mapping fractional vegetation cover (FVC). The major drawback of DPM is that it does not consider real endmember conditions and multiple scattering between soil and vegetation. An analysis of FVC uncertainties caused by these model deficiencies is still lacking. Here, we first calculated the FVC theoretical uncertainty caused by reflectance uncertainties based on the law of prapagation of uncertainty (LPU). Then, we tested the performance of DPM using six VIs over 3-D forest scenes. We simulated both Aqua-MODIS and Landsat-OLI surface reflectance (SR) at their corresponding spatial resolutions and spectral response functions (SRFs) using a well-validated 3-D radiative transfer (RT) model which helps to separate the model and input uncertainties. We found that ratio vegetation index (RVI)- and enhanced vegetation index (EVI)-based models were most affected by sensors, followed by the normalized difference vegetation index (NDVI)-, enhanced vegetation index 2 (EVI2)-, renormalized difference vegetation index (RDVI)-, and difference vegetation index (DVI)-based models. Without considering SR uncertainties, the DVI-based model performed best (FVC absolute difference < 0.1); however, the commonly used NDVI model reached a maximum difference of 0.35. At the same time, input uncertainty increased the uncertainty of FVC retrieval. We noticed that the increase of solar zenith angle (SZA) resulted in a clear increase of retrieved FVC under the uniform distribution, which can be explained by the increased shadow proportion. Besides, model accuracy was dominated by the purity of soil (vegetation) endmember in low (high) vegetation cover area. This study provides a reference for the selection of the optimal VI for FVC retrieval based on the DPM.
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- 2022
26. On a distance-constrained graph labeling to model cooperation
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David W. Mauro, Kirsti Kuenzel, John P. Georges, and Per Sebastian Skardal
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Combinatorics ,Graph labeling ,Applied Mathematics ,Image (category theory) ,Discrete Mathematics and Combinatorics ,Function (mathematics) ,Absolute difference ,Infimum and supremum ,Tree (graph theory) ,Graph ,Real number ,Mathematics - Abstract
Inspired by distance-constrained graph labelings that model the assignment of frequencies to transmitters, we introduce a distance-constrained labeling of connected graphs that models the assignment of frequencies to oscillators. For a graph G and a vector of nonnegative real numbers k = ( k 1 , k 2 , … , k p ) , an L ∗ ( G ; k ) -labeling is any function f from V ( G ) into R such that for each i , 1 ≤ i ≤ p , | f ( v ) − f ( w ) | ≤ k i if d ( v , w ) = i . The span of f is the absolute difference between the supremum and infimum of the image of f , and λ G , k ∗ is the maximum span over all L ∗ ( G , k ) labelings. In this paper, we explore the properties of λ G , k ∗ as a function of k , including continuity. And, for p = 2 , we establish λ G , k ∗ when G is either a tree or a cycle.
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- 2022
27. Ultrasound Elasticity Imaging System with Chirp-Coded Excitation for Assessing Biomechanical Properties of Elasticity Phantom
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Guan-Chun Chun, Hsing-Jung Chiang, Kuan-Hung Lin, Chien-Ming Li, Pei-Jarn Chen, and Tainsong Chen
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Tukey window ,chirp-coded pulse ,cross-correlation ,absolute difference ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
The biomechanical properties of soft tissues vary with pathological phenomenon. Ultrasound elasticity imaging is a noninvasive method used to analyze the local biomechanical properties of soft tissues in clinical diagnosis. However, the echo signal-to-noise ratio (eSNR) is diminished because of the attenuation of ultrasonic energy by soft tissues. Therefore, to improve the quality of elastography, the eSNR and depth of ultrasound penetration must be increased using chirp-coded excitation. Moreover, the low axial resolution of ultrasound images generated by a chirp-coded pulse must be increased using an appropriate compression filter. The main aim of this study is to develop an ultrasound elasticity imaging system with chirp-coded excitation using a Tukey window for assessing the biomechanical properties of soft tissues. In this study, we propose an ultrasound elasticity imaging system equipped with a 7.5-MHz single-element transducer and polymethylpentene compression plate to measure strains in soft tissues. Soft tissue strains were analyzed using cross correlation (CC) and absolution difference (AD) algorithms. The optimal parameters of CC and AD algorithms used for the ultrasound elasticity imaging system with chirp-coded excitation were determined by measuring the elastographic signal-to-noise ratio (SNRe) of a homogeneous phantom. Moreover, chirp-coded excitation and short pulse excitation were used to measure the elasticity properties of the phantom. The elastographic qualities of the tissue-mimicking phantom were assessed in terms of Young’s modulus and elastographic contrast-to-noise ratio (CNRe). The results show that the developed ultrasound elasticity imaging system with chirp-coded excitation modulated by a Tukey window can acquire accurate, high-quality elastography images.
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- 2015
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28. Deep learning model for automatic contouring of cardiovascular substructures on radiotherapy planning CT images: Dosimetric validation and reader study based clinical acceptability testing
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Robin Wijsman, Jonas Teuwen, Johan Bussink, B. Stam, M. Fernandes, René Monshouwer, and Dominic A.X. Schinagl
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Organs at Risk ,medicine.medical_specialty ,Lung Neoplasms ,Contrast enhancement ,IMPACT ,medicine.medical_treatment ,AUTO-SEGMENTATION ,Locally advanced ,Absolute difference ,NSCLC ,TOXICITY ,Deep Learning ,All institutes and research themes of the Radboud University Medical Center ,Segmentation ,Carcinoma, Non-Small-Cell Lung ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Contouring ,business.industry ,Radiotherapy Planning, Computer-Assisted ,Deep learning ,Cardiac radiotoxicity ,Hematology ,Surface dice ,Women's cancers Radboud Institute for Health Sciences [Radboudumc 17] ,LUNG-CANCER PATIENTS ,Radiation therapy ,Oncology ,Great vessels ,SURVIVAL ,HEART ,Artificial intelligence ,Radiology ,Lung cancer ,Tomography, X-Ray Computed ,business ,Rare cancers Radboud Institute for Health Sciences [Radboudumc 9] ,Automatic cardiac contouring - Abstract
Background and purpose: Large radiotherapy (RT) planning imaging datasets with consistently contoured cardiovascular structures are essential for robust cardiac radiotoxicity research in thoracic cancers. This study aims to develop and validate a highly accurate automatic contouring model for the heart, cardiac chambers, and great vessels for RT planning computed tomography (CT) images that can be used for dose-volume parameter estimation. Materials and methods: A neural network model was trained using a dataset of 127 expertly contoured planning CT images from RT treatment of locally advanced non-small-cell lung cancer (NSCLC) patients. Evaluation of geometric accuracy and quality of dosimetric parameter estimation was performed on 50 independent scans with contrast and without contrast enhancement. The model was further evaluated regarding the clinical acceptability of the contours in 99 scans randomly sampled from the RTOG-0617 dataset by three experienced radiation oncologists. Results: Median surface dice at 3 mm tolerance for all dedicated thoracic structures was 90% in the test set. Median absolute difference between mean dose computed with model contours and expert contours was 0.45 Gy averaged over all structures. The mean clinical acceptability rate by majority vote in the RTOG-0617 scans was 91%. Conclusion: This model can be used to contour the heart, cardiac chambers, and great vessels in large datasets of RT planning thoracic CT images accurately, quickly, and consistently. Additionally, the model can be used as a time-saving tool for contouring in clinic practice. (c) 2021 The Authors. Published by Elsevier B.V. Radiotherapy and Oncology 165 (2021) 52-59 This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
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- 2021
29. Assessment of automatic cephalometric landmark identification using artificial intelligence
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Viana Grace, David Avenetti, Flavio Sanchez, T. Peter Tsay, Galina Bulatova, and Budi Kusnoto
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Landmark ,Cephalometry ,business.industry ,Anterior nasal spine ,Orthodontics ,Absolute difference ,Incisor ,Radiography ,Identification (information) ,medicine.anatomical_structure ,Otorhinolaryngology ,Artificial Intelligence ,Statistical significance ,medicine ,Surgery ,Nasion ,Artificial intelligence ,Oral Surgery ,Posterior nasal spine ,business ,Mathematics - Abstract
Hypothesis and Objective: To compare the accuracy of cephalometric landmark identification between Artificial Intelligence (AI) Deep Learning Convolutional Neural Networks YOLOv3 algorithm and Manually Traced (MT) group. Methods: AAOF Legacy Denver collection was used to obtain 110 cephalometric images for this study. Lateral cephalograms were digitized by orthodontic resident in Dolphin Imaging after intra- and inter reliability check. The same images were uploaded to AI software Ceppro DDH Inc. Cartesian system of coordinates with Sela as 0:0 was used to extract x and y coordinate for 16 cephalometric points: Nasion, A point, B point, Menton, Gonion, Upper incisor tip, Lower incisor tip, Upper incisor apex, Lower incisor apex, Anterior Nasal Spine, Posterior Nasal Spine, Pogonion, Pterigomaxillary fissure point, Basion, Articulare and Orbitale. The mean distances were assessed relative to the reference value of 2 mms. Student paired t-tests at significance level of 5 % were used to compare the mean differences in each of the X- and Y-components. SPSS (IBM-vs. 27.0) software was use for the data analysis. Results: The results showed that there is no statistical difference for 12 out of 16 points when analyzing absolute difference between MT and AI group. Success detection rate for AI within 2 mm while comparing MT and AI group was 75 % and 93% within 4 mm. Conclusions: AI could be considered a promising tool to facilitate cephalometric tracing process in routine clinical practice and in research settings. Funding: no funding. IRB and/or ACC Protocol #: 2019-1180. Notice of Determination: activity Does Not Represent Human Subjects Research.
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- 2021
30. A Novel Method for 3D Nanoscale Tracking of 100 nm Polystyrene Particles in Multi-Wavelength Evanescent Fields Microscopy – Absolute Difference Height Verification –
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Aran Blattler, Keisuke Suzuki, Panart Khajornrungruang, and Soraya Saenna
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Materials science ,business.industry ,Mechanical Engineering ,Multi wavelength ,Absolute difference ,Tracking (particle physics) ,Industrial and Manufacturing Engineering ,chemistry.chemical_compound ,Optics ,chemistry ,Microscopy ,Polystyrene ,business ,Nanoscopic scale - Abstract
Total internal reflection is an optical imaging technique for nanoparticle tracking and observation employing the scattered light from an evanescent field near the interface or reference surface. Generally, the nanoparticle behavior is the three-dimensional Brownian motion in an aqueous medium. The motion can be traced by an optical microscopy, but it cannot be traced by an electron microscopy technique. In the three-dimensional nanoparticle moving position, the X and Y positions are parallel to the surface, which can be traced by the general microscopy techniques. However, the height position Z of a nanoparticle perpendicular to the surface could not be traced without the longitudinal scanning method. Here, a novel method is proposed to investigate the 3D position of nanoparticles by applying multi-wavelength evanescent fields microscopy, which has a high spatial resolution in the Z-direction without longitudinal scanning. This paper focuses on the verification of measurement in the Z-direction. A piezoelectric actuator was employed to control the nanoparticle displacement in height Z. Standard polystyrene 100 nm particles were randomly adhered on a spherical tip that connected with the piezoelectric actuator. The spherical tip was essentially made from an optical adhesive (n = 1.348) with a refractive index close to the water for decreasing the unnecessary signal from the tip-self during nanoparticle observation in the water. The proposed method could obtain the multi-wavelength scattering lights from the observed nanoparticles by an 8-bit color camera with higher than 50 frames per second recording to investigate the 3D nanoscale tracking. The X and Y positions of nanoparticles were determined by the centroid of the scattering light intensities. The height Z was determined from the logarithm ratios between the detected scattering light intensities of both wavelengths. The measurement repeatability of the absolute difference in height between nanoparticles could be measured less than ±16 nm by using the proposed method. The penetration height measurability range was approximated at 250 nm from the reference surface.
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- 2021
31. Can general surgery interns accurately measure their own technical skills? Analysis of cognitive bias in surgical residents’ self-assessments
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Thomas J. Fahey, Iskander Bagautdinov, Aleksandr Karnick, Jessica Limberg, Dessislava Stefanova, David Fehling, Victoria G. Aveson, and Jessica W. Thiesmeyer
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Male ,Self-Assessment ,medicine.medical_specialty ,Percentile ,business.industry ,General surgery ,MEDLINE ,Internship and Residency ,Reproducibility of Results ,Absolute difference ,Surgical training ,Cognitive bias ,Knot tying ,Education, Medical, Graduate ,General Surgery ,Cohort ,medicine ,Humans ,Female ,Surgery ,Clinical Competence ,Educational Measurement ,Technical skills ,business ,Retrospective Studies - Abstract
Accurate self-assessment of knowledge and technical skills is key to self-directed education required in surgical training. We aimed to investigate the presence and magnitude of cognitive bias in self-assessment among a cohort of surgical interns.First-year general surgery residents self-assessed performance on a battery of technical skill tasks (knot tying, suturing, vascular anastomosis, Fundamentals of Laparoscopic Skills peg transfer and intracorporeal suturing) at the beginning of residency. Each self-assessment was compared to actual performance. Bias and deviation were defined as arithmetic and absolute difference between actual and estimated scores. Spearman correlation assessed covariation between actual and estimated scores. Improvement in participant performance was analyzed after an end-of-year assessment.Participants (N = 34) completed assessments from 2017 to 2019. Actual and self-assessment scores were positively correlated (0.55, P.001). Residents generally underestimated performance (bias -4.7 + 8.1). Participants who performed above cohort average tended to assess themselves more negatively (bias -7.3 vs -2.3) and had a larger discrepancy between self and actual scores than below average performers (deviation index 9.7 + 8.2 vs 3.8 + 3.1, P.05). End-of-year total scores improved in 31 (91.2%) participants by an average of 11 points (90 possible). Least accurate residents in initial self-assessments (deviation indices75th percentile) improved less than more accurate residents (median 5 vs 16 points, P.05). All residents with a deviation index75 percentile underestimated their performance.Cognitive bias in technical surgical skills is apparent in first-year surgical residents, particularly in those who are higher performers. Inaccuracy in self-assessment may influence improvement and should be addressed in surgical training.
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- 2021
32. Virtual Analysis of Segmental Bimaxillary Surgery: A Validation Study
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Alexandru Diaconu, Jens Jørgen Thorn, Else Marie Pinholt, Michael Boelstoft Holte, and Janne Ingerslev
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Adult ,Male ,medicine.medical_specialty ,Validation study ,medicine.medical_treatment ,Osteotomy, Sagittal Split Ramus ,Orthognathic surgery ,Sagittal split osteotomy ,Absolute difference ,Genioplasty ,Young Adult ,03 medical and health sciences ,Imaging, Three-Dimensional ,0302 clinical medicine ,Quantitative assessment ,Humans ,Osteotomy, Le Fort ,Postoperative outcome ,Medicine ,Orthognathic Surgical Procedures ,business.industry ,Orthognathic Surgery ,Reproducibility of Results ,030206 dentistry ,Cone-Beam Computed Tomography ,Confidence interval ,Surgery ,Otorhinolaryngology ,030220 oncology & carcinogenesis ,Female ,Oral Surgery ,business - Abstract
Purpose: Three-dimensional (3D) assessment of orthognathic surgery is often time consuming, relies on manual re-identification of anatomical landmarks or is limited to non-segmental osteotomies. The purpose of the present study was to propose and validate an automated approach for 3D assessment of the accuracy and postoperative outcome of segmental bimaxillary surgery. Methods: A semi-automatic approach was developed and validated for virtual surgical analysis (VSA) of segmental bimaxillary surgery using a pair of pre- and postoperative (2 weeks) cone-beam computerized tomography (CBCT) scans. The output of the VSA, the accuracy of the surgical outcome, was calculated as 3D translational and rotational differences between the planned and postoperative movements of the individual bone segments. To evaluate the reliability of the proposed VSA, intra-class correlation coefficients (ICC) were calculated at a 95% confidence interval on measurements of 2 observers. The VSA was deemed reliable if the ICC was excellent (> 0.80) and the absolute difference of the repeated intra- and inter-observer translational and rotational measurements were significantly lower (p < 0.05) than a hypothesized clinical relevant threshold of 1 voxel (0.45 mm) and 1 degree, respectively. Results: A total of 10 subjects (6 male; 4 women; mean age 24.4 years) with skeletal class 2 and 3, who underwent segmental bimaxillary surgery, 3-piece Le Fort I, bilateral sagittal split osteotomy and genioplasty, were recruited. The intra- and inter-observer reliability was excellent, ICC range [0.96 - 1.00]. The range of the mean absolute difference of the repeated intra- and inter-observer translational and rotational measurements were [0.07 mm (0.05) – 0.20 mm (0.19)] and [0.11˚ (0.08) - 0.63˚ (0.42)], respectively. This was significantly lower than the hypothesized clinical relevant thresholds (P
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- 2021
33. Infrared target detection based on the single-window average absolute gray difference algorithm
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Shokoufeh Aalaei, Hadi Shahraki, and Saed Moradi
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Degree (graph theory) ,Pixel ,Infrared ,Computer science ,Signal Processing ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Window (computing) ,Clutter ,Absolute difference ,Electrical and Electronic Engineering ,Real image ,Algorithm ,Signal - Abstract
In this research, an infrared small target detection method called single-window average absolute gray difference algorithm (SW-AAGD) is proposed. This algorithm is derived from the average absolute difference algorithm which is highly capable of enhancing targets and suppressing the background clutters in infrared images. A common challenge in the average absolute gray difference algorithm is the choice of proper target and background windows due to the blurred edges of the small target. In the proposed algorithm, a single window is used for the target and background windows. To address this issue, a degree of membership is defined for each existing pixel of these windows. The membership degrees of pixels in the main window are in accordance with the properties of real targets in infrared images. These values are estimated in a way that there is no need for determining the exact target and background areas. To estimate the efficiency of the proposed algorithm, the algorithm is applied on several real images that contain real targets and the results are compared to five well-known methods in terms of the signal to clutter ratio (SCR), background suppression factor (BSF) and receiving operating characteristic (ROC) curve. The results prove the effectiveness of the membership degree assignment on the overall performance of detection algorithm.
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- 2021
34. ProFitFun: a protein tertiary structure fitness function for quantifying the accuracies of model structures
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Rahul Kaushik and Kam Y. J. Zhang
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Statistics and Probability ,Fitness function ,Computer science ,Protein design ,Benchmarking ,Absolute difference ,Protein structure prediction ,Dihedral angle ,computer.software_genre ,Biochemistry ,Protein tertiary structure ,Computer Science Applications ,Computational Mathematics ,Protein structure ,Computational Theory and Mathematics ,Data mining ,Molecular Biology ,computer - Abstract
Motivation An accurate estimation of the quality of protein model structures typifies as a cornerstone in protein structure prediction regimes. Despite the recent groundbreaking success in the field of protein structure prediction, there are certain prospects for the improvement in model quality estimation at multiple stages of protein structure prediction and thus, to further push the prediction accuracy. Here, a novel approach, named ProFitFun, for assessing the quality of protein models is proposed by harnessing the sequence and structural features of experimental protein structures in terms of the preferences of backbone dihedral angles and relative surface accessibility of their amino acid residues at the tripeptide level. The proposed approach leverages upon the backbone dihedral angle and surface accessibility preferences of the residues by accounting for its N-terminal and C-terminal neighbors in the protein structure. These preferences are used to evaluate protein structures through a machine learning approach and tested on an extensive dataset of diverse proteins. Results The approach was extensively validated on a large test dataset (n = 25 005) of protein structures, comprising 23 661 models of 82 non-homologous proteins and 1344 non-homologous experimental structures. In addition, an external dataset of 40 000 models of 200 non-homologous proteins was also used for the validation of the proposed method. Both datasets were further used for benchmarking the proposed method with four different state-of-the-art methods for protein structure quality assessment. In the benchmarking, the proposed method outperformed some state-of-the-art methods in terms of Spearman’s and Pearson’s correlation coefficients, average GDT-TS loss, sum of z-scores and average absolute difference of predictions over corresponding observed values. The high accuracy of the proposed approach promises a potential use of the sequence and structural features in computational protein design. Availability and implementation http://github.com/KYZ-LSB/ProTerS-FitFun. Supplementary information Supplementary data are available at Bioinformatics online.
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- 2021
35. Difference‐equalisation based estimation of timing skew for time‐interleaved ADCs in communication systems.
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Li, Xin, Gao, Bo, Yan, Chenggang, Ding, Desheng, and Wu, Jianhui
- Abstract
A difference‐equalisation based method is presented to estimate timing skew adaptively in time‐interleaved analogue‐to‐digital converters (ADCs). By digital zero‐crossing detection and calculating the mean of the absolute difference between adjacent sub‐ADC's outputs, the timing mismatch information for each channel can be identified easily. Simulation results demonstrate that the proposed method can estimate timing skew accurately. Furthermore, the proposed method requires far fewer samples to estimation than the previous methods. [ABSTRACT FROM AUTHOR]
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- 2019
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36. Comparison of the fully penetrating well drawdown in leaky aquifers between finite and infinite radius of influence under steady-state pumping conditions.
- Author
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BRENČIČ, Mihael
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- *
AQUIFERS , *AQUITARDS , *GROUNDWATER , *WATER supply , *HYDROGEOLOGY - Abstract
In the paper theoretical derivation of steady state groundwater well pumping from leaky aquifers with infinite and finite radius of influence are presented. Based on the extensive literature review following mainly Jacob and Hantush work equations were derived from the cylindrical Bessel partial differential equation and results expressed in the combination of modified Bessel functions of zero order of the first and the second kind (I0, K0). We have shown that equation for steady state well pumping in the infinite aquifer is infinite limit of Hantush integral. Mathematical characteristics of solutions for infinite and finite radius of well influence were combined in the way that they can be represented as relative and absolute differences of drawdowns of each model. In the case when available data do not allow us to make a decision on the type of the radius of influence of the pumping well, they can help us in the interpretation of various errors due to application of different analytical models of pumping test. [ABSTRACT FROM AUTHOR]
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- 2018
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37. The Public Forum – Sharing the News with the Public
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Gauch, Ronald R.
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- 2009
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38. A 43.1TOPS/W Energy-Efficient Absolute-Difference-Accumulation Operation Computing-In-Memory With Computation Reuse
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Hoi-Jun Yoo, Sangyeob Kim, Sangjin Kim, and Soyeon Um
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Reduction (complexity) ,CMOS ,Computer science ,Computation ,Multiplication ,Parallel computing ,Absolute difference ,Electrical and Electronic Engineering ,Reuse ,Quantization (image processing) ,Efficient energy use - Abstract
Recently, Computing-In-Memory (CIM) processors have been proposed to achieve high energy-efficiency by reducing data movement and solving memory bottlenecks. Furthermore, a network with high accurate image classification has been introduced through the Absolute-Difference-Accumulation (ADA) operation instead of the multiplication-and-accumulation operation, which is widely used in DNN. ADA operation provides not only opportunities for high energy-efficient DNN accelerating by reducing multiplication but also a chance to reuse computation results. However, the previous CIM processor cannot reuse previous computation results for other computations. In this brief, we propose a high accurate and high energy-efficient ADA-CIM processor that with two key features: 1) computation reuse for low-power, resulting in a 49.5% CIM operation power reduction, and 2) low-cost sign prediction core with 3-bit activation and weight quantization for high utilization. From the two key features, the proposed ADA-CIM processor is simulated in 28 nm CMOS technology and occupies 3.78 mm2. It consumes 2.77mW and achieves 43.1 TOPS/W energy-efficiency with a high-accuracy of 91.62% at CIFAR-10 (ResNet-20).
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- 2021
39. Investigation of motor self-monitoring deficits in schizophrenia with passivity experiences using a novel modified joint position matching paradigm
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Yi Nam Suen, Christy Lai Ming Hui, Eric Y.H. Chen, Sherry Kit Wa Chan, Edwin Ho Ming Lee, Wing Chung Chang, and Chi Sing Law
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medicine.medical_specialty ,Psychosis ,Matching (statistics) ,Passivity ,Cognition ,General Medicine ,Absolute difference ,medicine.disease ,030227 psychiatry ,03 medical and health sciences ,Psychiatry and Mental health ,0302 clinical medicine ,Physical medicine and rehabilitation ,Schizophrenia ,Self-monitoring ,medicine ,Pharmacology (medical) ,In patient ,Psychology ,030217 neurology & neurosurgery ,Biological Psychiatry - Abstract
Numerous studies have identified deficits in the self-monitoring system that are associated with schizophrenia. However, the tasks used in the few previous studies generally involved complex cognitive processes and rarely compared between patients with and without passivity experiences (PE). Here, we examined the deficits in internal motor predictive representation in patients with and without PE, and in healthy controls using a novel paradigm which involved minimal cognitive processes. All participants completed a modified joint position matching (mJPM) task, in which they were required to replicate a voluntary, a passive verbally-cued, and a passive tactile-cued movement under blinded conditions. The absolute difference between the target spot and replicated spot was measured and compared. We hypothesised that if there was a failure in the internal motor predictive representation, patients with PEs would replicate less accurately in the voluntary condition, relative to passive conditions while the healthy controls would be more accurate, and, therefore, significant interactions between groups and conditions would be revealed. Both healthy controls and patients without PEs replicated more accurately in the voluntary condition compared with the passive conditions. The patients with PEs were less accurate in the voluntary condition compared with the passive tactile condition. A significant interaction was observed between patients with vs. without PEs × voluntary vs. passive tactile conditions. The findings suggested the relationship between deficits in motor self-monitoring in the prediction process and PEs, thus showing the need to highlight the link between motor performance and PEs.
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- 2021
40. Validation study of a software for proprioceptive evaluation
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Adriano Prado Simão, Denise Hollanda Iunes, Renato Aparecido de Souza, Henrique Franco Ferreira, Leonardo César Carvalho, and Paulo Alexandre Bressan
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musculoskeletal diseases ,medicine.medical_specialty ,Wilcoxon signed-rank test ,Proprioception ,Construct validity ,General Medicine ,Absolute difference ,Physical medicine and rehabilitation ,medicine.anatomical_structure ,medicine ,Shoulder joint ,Joint (geology) ,Reliability (statistics) ,Mathematics ,Lateral dominance - Abstract
Objective: To validate the PhisioPlay software for proprioceptive evaluation of the shoulder joint based on the data obtained by isokinetic dynamometry equipment. Methods: Thirty-one individuals constituted a single group for proprioceptive evaluation of both shoulder joints by means of joint position sense (JPS). The testing protocol of PhisioPlay consisted of the abduction movement of the shoulder to the target angles of 45° and 90° and the maintenance of these positions for 30 seconds. In the isokinetic dynamometer, the test was performed using its proprioceptive evaluation protocol for the same movement, target angles, and maintenance time established for the previous test. Results: For the 90° variables, statistical analysis pointed to agreement for the dominant limb in relation to the mean angulation and the absolute difference and for the non-dominant limb in relation to the absolute difference. The results of mean comparisons of the absolute differences via the Wilcoxon Test corroborate the literature regarding the behavior of the JPS considering joint amplitude, lateral dominance, and greater or lesser torque affecting the joint. Reliability and sensitivity measures also strengthen the conclusions. Conclusion: The results point to the construct validity of the PhisioPlay software for evaluating the JPS of the shoulder joint at 45° and 90° and suggest that the JPS is more influenced by the angle of the joint during the motor task than by the lateral dominance.
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- 2021
41. The Effect of the Number of Key-Frames on the Facial Emotion Recognition Accuracy
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Suhaila N. Mohammed and Alia Karim Abdul Hassan
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Computer science ,business.industry ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Pattern recognition ,Absolute difference ,Fuzzy logic ,Face (geometry) ,Selection (linguistics) ,Graph (abstract data type) ,Expressed emotion ,Artificial intelligence ,business ,Cluster analysis ,Set (psychology) - Abstract
Key-frame selection plays an important role in facial expression recognition systems. It helps in selecting the most representative frames that capture the different poses of the face. The effect of the number of selected keyframes has been studied in this paper to find its impact on the final accuracy of the emotion recognition system. Dynamic and static information is employed to select the most effective key-frames of the facial video with a short response time. Firstly, the absolute difference between the successive frames is used to reduce the number of frames and select the candidate ones which then contribute to the clustering process. The static-based information of the reduced sets of frames is then given to the fuzzy C-Means algorithm to select the best C-frames. The selected keyframes are then fed to a graph mining-based facial emotion recognition system to select the most effective sub-graphs in the given set of keyframes. Different experiments have been conducted using Surrey Audio-Visual Expressed Emotion (SAVEE) database and the results show that the proposed method can effectively capture the keyframes that give the best accuracy with a mean response time equals to 2.89s.
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- 2021
42. Automated segmentation of an intensity calibration phantom in clinical CT images using a convolutional neural network
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Akihiro Kawasaki, Yoshito Otake, Mazen Soufi, Masaki Takao, Yoshinobu Sato, Keisuke Uemura, and Nobuhiko Sugano
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Computer science ,0206 medical engineering ,Biomedical Engineering ,Health Informatics ,02 engineering and technology ,Absolute difference ,Convolutional neural network ,Imaging phantom ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Sørensen–Dice coefficient ,Region of interest ,Hounsfield scale ,medicine ,Radiology, Nuclear Medicine and imaging ,Segmentation ,Quantitative computed tomography ,medicine.diagnostic_test ,business.industry ,Pattern recognition ,General Medicine ,020601 biomedical engineering ,Computer Graphics and Computer-Aided Design ,Computer Science Applications ,Surgery ,Computer Vision and Pattern Recognition ,Artificial intelligence ,business - Abstract
In quantitative computed tomography (CT), manual selection of the intensity calibration phantom’s region of interest is necessary for calculating density (mg/cm3) from the radiodensity values (Hounsfield units: HU). However, as this manual process requires effort and time, the purposes of this study were to develop a system that applies a convolutional neural network (CNN) to automatically segment intensity calibration phantom regions in CT images and to test the system in a large cohort to evaluate its robustness. This cross-sectional, retrospective study included 1040 cases (520 each from two institutions) in which an intensity calibration phantom (B-MAS200, Kyoto Kagaku, Kyoto, Japan) was used. A training dataset was created by manually segmenting the phantom regions for 40 cases (20 cases for each institution). The CNN model’s segmentation accuracy was assessed with the Dice coefficient, and the average symmetric surface distance was assessed through fourfold cross-validation. Further, absolute difference of HU was compared between manually and automatically segmented regions. The system was tested on the remaining 1000 cases. For each institution, linear regression was applied to calculate the correlation coefficients between HU and phantom density. The source code and the model used for phantom segmentation can be accessed at https://github.com/keisuke-uemura/CT-Intensity-Calibration-Phantom-Segmentation . The median Dice coefficient was 0.977, and the median average symmetric surface distance was 0.116 mm. The median absolute difference of the segmented regions between manual and automated segmentation was 0.114 HU. For the test cases, the median correlation coefficients were 0.9998 and 0.999 for the two institutions, with a minimum value of 0.9863. The proposed CNN model successfully segmented the calibration phantom regions in CT images with excellent accuracy.
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- 2021
43. Global reliability sensitivity analysis index and its efficient numerical simulation solution in presence of both random and interval hybrid uncertainty
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Chunyan Ling, Zhenzhou Lu, Suting Zhou, and Wanying Yun
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Control and Optimization ,Computer simulation ,Reliability (computer networking) ,0211 other engineering and technologies ,Conditional probability ,02 engineering and technology ,Interval (mathematics) ,Absolute difference ,Computer Graphics and Computer-Aided Design ,Upper and lower bounds ,Computer Science Applications ,020303 mechanical engineering & transports ,0203 mechanical engineering ,Control and Systems Engineering ,Applied mathematics ,Sensitivity (control systems) ,Software ,Realization (probability) ,021106 design practice & management ,Mathematics - Abstract
In the presence of both random and interval hybrid uncertainty (RI-HU), investigating global reliability sensitivity (GRS) can identify the effect of random input on the structural safety globally. To this end, this work establishes the GRS index model and its corresponding efficient solution, and the innovation includes three aspects. Firstly, the GRS of the random input is defined by the average absolute difference between the failure probability upper bound (FP-UB) and the conditional FP-UB on the fixed random input under the RI-HU, and it can reflect the effect of the fixed random input on the structural safety. Secondly, the conditional FP-UB on fixing the random input at the realization is approximated by the conditional FP-UB on fixing the random input in a differential interval. Then the conditional probability theorem can be employed to convert estimating the GRS into the state recognition of the samples, which is the by-product of estimating the FP-UB by the numerical simulation. Finally, by the strategy of surrogating the performance function twice, the meta-importance sampling method is developed to efficiently estimate the GRS in presence of the RI-HU. The rationality of the proposed GRS index model and the efficiency of the developed estimation method are fully verified by the numerical and engineering examples.
- Published
- 2021
44. Intraoperative Computed Tomography for Registration of Stereotactic Frame in Frame-Based Deep Brain Stimulation
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Joshua M. Rosenow, Mark J. Nolt, Michael R. Jones, and Archit Bharathwaj Baskaran
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Scanner ,medicine.diagnostic_test ,business.industry ,Deep Brain Stimulation ,Frame (networking) ,Anterior commissure ,Magnetic resonance imaging ,Absolute difference ,Standard deviation ,Electrodes, Implanted ,Stereotaxic Techniques ,Imaging, Three-Dimensional ,Posterior commissure ,Medical imaging ,Humans ,Medicine ,Surgery ,Neurology (clinical) ,Tomography, X-Ray Computed ,Nuclear medicine ,business - Abstract
Background Deep brain stimulation (DBS) electrode placement utilizing a frame-based technique requires registration of the stereotactic frame with computed tomography (CT) or magnetic resonance (MR) imaging. This traditionally has been accomplished with a conventional CT scanner. In recent years, intraoperative CT has become more prevalent. Objective To compare the coordinates obtained with intraoperative CT and conventional CT for registration of the stereotactic frame for DBS. Methods Patients undergoing DBS electrode placement between 2015 and 2017, who underwent both conventional and intraoperative CT for registration of the stereotactic frame, were included for analysis. The coordinates for the stereotactic target, anterior commissure, and posterior commissure for each CT method were recorded. The mean, maximum, minimum, and standard deviation of the absolute difference for each of the paired coordinates was calculated. Paired t-tests were performed to test for statistical significance of the difference. The directional difference as well as the vector error between the paired coordinates was also calculated. Results The mean absolute difference between conventional and intraoperative CT for the coordinate pairs was less than 0.279 mm or 0.211 degrees for all coordinate pairs analyzed. This was not statistically significant for any of the coordinate pairs. Moreover, the maximum absolute difference between all coordinate pairs was 1.04 mm. Conclusion Intraoperative CT imaging provides stereotactic frame registration coordinates that are similar to those obtained by a standard CT scanner. This may save time and hospital resources by obviating the need for the patient to go to the radiology department for a CT scan.
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- 2020
45. Dynamics of the Physical Fitness Status in Students 17-18 years of the 'Tourism' Specialized Field during a Trans-Season Stage
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V. Labartkava, O. Zalisko, I. Kushnir, and K. Labartkava
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business.industry ,Physical fitness ,Repeated measures design ,030229 sport sciences ,Absolute difference ,Test (assessment) ,03 medical and health sciences ,0302 clinical medicine ,Dynamics (music) ,030212 general & internal medicine ,Analysis of variance ,Stage (hydrology) ,business ,Psychology ,Tourism ,Demography - Abstract
The research aimed to study dynamics of the physical fitness status in students of the “Tourism” specialized field during a trans-season stage. Totally 100 university students studying “Tourism” as a business service were involved into the physical fitness testing (48 males and 52 females). A half of the participants studied in the Classic University and another half − in the Sport University. Monthly testing was conducted seven times from September to March using a complex test Kontreks–2. The scoring system consists of eleven indicators: five of them are biomedical: age, body weight, blood pressure, heart rate, reducing pulse; a six – motor: flexibility, speed, dynamic power, power, speed and overall endurance. Linear regression was used with a purpose to study trends of the physical fitness during the trans-season stage. Two-ways ANOVA was used to determine differences between samples. One-way ANOVA with repeated measures was used to evaluate test-retest reliability (ICC=0.094). A significant superiority of students from the Sport University vs. Classic University was noticed during the seven months preparation stage (17.6%, p
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- 2020
46. Intelligent Detection and Recovery of Missing Electric Load Data Based on Cascaded Convolutional Autoencoders
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Li Dong, Yuanyi Chen, Wang Xin, Guode Ying, Wei Ruan, and Qiang Gao
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Article Subject ,Electrical load ,Computer science ,020209 energy ,Inpainting ,02 engineering and technology ,Absolute difference ,Grid ,Missing data ,computer.software_genre ,Computer Science Applications ,QA76.75-76.765 ,030507 speech-language pathology & audiology ,03 medical and health sciences ,Electric power system ,Robustness (computer science) ,0202 electrical engineering, electronic engineering, information engineering ,Preprocessor ,Computer software ,Data mining ,0305 other medical science ,computer ,Software - Abstract
Under the background of Energy Internet, the ever-growing scale of the electric power system has brought new challenges and opportunities. Numerous categories of measurement data, as the cornerstone of communication, play a crucial role in the security and stability of the system. However, the present sampling and transmission equipment inevitably suffers from data missing, which seriously degrades the stable operation and state estimation. Therefore, in this paper, we consider the load data as an example and first develop a missing detection algorithm in terms of the absolute difference sequence (ADS) and linear correlation to detect any potential missing data. Then, based on the detected results, we put forward a missing recovery model named cascaded convolutional autoencoders (CCAE), to recover those missing data. Innovatively, a special preprocessing method has been adopted to reshape the one-dimensional load data as a two-dimensional matrix, and hence, the image inpainting technologies can be conducted to address the problem. Also, CCAE is designed to reconstruct the missing data grade by grade due to its priority strategy, which enhances the robustness upon extreme missing situations. The numerical results on the load data of the Belgium grid validate the promising performance and effectiveness of the proposed solutions.
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- 2020
47. Censored patients in Kaplan–Meier plots of cancer drugs: An empirical analysis of data sharing
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Kate Rosen, Emerson Y. Chen, and Vinay Prasad
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0301 basic medicine ,Cancer Research ,medicine.medical_specialty ,Cancer drugs ,Antineoplastic Agents ,Kaplan-Meier Estimate ,Absolute difference ,03 medical and health sciences ,0302 clinical medicine ,Neoplasms ,Internal medicine ,medicine ,Overall survival ,Humans ,Time point ,Survival analysis ,Randomized Controlled Trials as Topic ,Retrospective Studies ,Retrospective review ,Information Dissemination ,business.industry ,030104 developmental biology ,Oncology ,030220 oncology & carcinogenesis ,Censoring (clinical trials) ,Oncology drugs ,business - Abstract
Introduction Kaplan–Meier survival analysis, the cornerstone of evaluating efficacy of oncology drugs in randomised controlled trials (RCTs), assumes censored patients are neither healthier nor sicker than those followed. We sought to examine whether censoring patterns differ between the control and experimental arms in one oncology journal that mandates the reporting of the number of patients censored. Methods In this retrospective review, proportion of censoring and study design data were gathered from RCTs published in The Lancet Oncology that reported Kaplan–Meier curves between May 2018 and August 2019. Differential censoring rates were analysed at the 1st, 3rd, 6th, and overall time points in each study. Analysis was stratified by curves reporting progression-free survival (PFS) or overall survival (OS) end-points. Results Of the 160 articles reviewed, 29 studies with 51 Kaplan–Meier curves were eligible. In both OS (N = 25) and PFS curves (N = 26), the absolute weighted difference in censoring between the control and experimental arms was initially positive, indicating more censoring in the control arm (first time point OS: 0.32%; PFS: 2.00%). The absolute difference then became negative, indicating more censoring in the experimental arm as time progressed (end-of-study OS: −7.54%; PFS: −9.09%). Conclusion Differences in censoring between control and experimental arms of cancer RCTs suggest that there could be systematic bias present at various study time points that may influence key results. Further investigation is needed, as possible reasons include study assignment disappointment, inappropriate follow-up length, lack of efficacy, or intolerable toxicity, each predominant at specific time points after randomisation.
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- 2020
48. MPA‐Net: multi‐path attention stereo matching network
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Xiaowei Yang, Zu Liu Yang, Haiwei Sang, and Yong Zhao
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Image fusion ,Matching (statistics) ,Computer science ,business.industry ,Feature extraction ,020206 networking & telecommunications ,Pattern recognition ,02 engineering and technology ,Absolute difference ,Encoding (memory) ,Signal Processing ,0202 electrical engineering, electronic engineering, information engineering ,Fuse (electrical) ,Benchmark (computing) ,020201 artificial intelligence & image processing ,Computer Vision and Pattern Recognition ,Artificial intelligence ,Electrical and Electronic Engineering ,business ,Software ,Decoding methods - Abstract
A novel learning-based end-to-end network for stereo matching, named Multi-path Attention Stereo Matching (MPA-Net), is introduced in this study. Different from existing methods, the multi-path attention aggregation module is designed firstly, named MPA, which is a unified structure using three different parallel layers with a respective attention mechanism to extract the multi-scale informational features. Secondly, the method of cost volume construction, which differs from the traditional stereo matching methods, is extended. And then, the absolute difference between two input features is calculated. Furthermore, a u-shaped structure with 3D attention gate is selected as the encoder-decoder module. Specifically, the module is used to fuse the encoding features to their corresponding decoding features under the supervision of the authors' attention gate with skip-connection, and thus exploit more significant information for matching cost regularisation and disparity prediction. Finally, specific experiments are conducted to evaluate their network on SceneFlow, KITTI2012 and KITTI2015 data sets. The results show that their method achieves a better improvement in disparity maps prediction compared with some existing state-of-the-art methods on KITTI benchmark.
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- 2020
49. Change detection with absolute difference of multiscale deep features
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Qiang Zhao, Mo Zhou, Yaobin Zou, and Rui Huang
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0209 industrial biotechnology ,Computer science ,business.industry ,Cognitive Neuroscience ,Pattern recognition ,02 engineering and technology ,Absolute difference ,Computer Science Applications ,Image (mathematics) ,020901 industrial engineering & automation ,Artificial Intelligence ,Feature (computer vision) ,0202 electrical engineering, electronic engineering, information engineering ,Benchmark (computing) ,020201 artificial intelligence & image processing ,Artificial intelligence ,Layer (object-oriented design) ,business ,Change detection ,Resolution (algebra) - Abstract
Most of the previous change detection methods are designed based on the difference of two images. However, directly using intensity or the features to generate difference image may be easily affected by the illumination and camera pose variations. In this paper, we show that accurate change detection results can be obtained by fusing the absolute difference of multiscale deep features of the reference and query images. Specifically, we build a change detection network, which computes absolute difference of the multiscale deep features of image pairs and learns adaptive features for change detection. The proposed network is based on off-the-shelf CNNs, whose convolutional layer blocks are used as feature extracting modules to extract multiscale deep features. We devise intra and cross encoding modules. The intra encoding modules are used for learning change related features from extracted features. These features are used for generating absolute difference features (ADFs). By progressively fusing the ADFs from high to low layers with cross encoding modules, we obtain full resolution of change detection result. Extensive experiments on three change detection benchmark datasets validate the superiority and effectiveness of the proposed method over the state-of-the-art change detection methods.
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- 2020
50. Are Commercial Financial Databases Reliable? New Evidence from Korea.
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Hyunjung Nam, Won Gyun No, and Youngsu Lee
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The quality of financial information is crucial for the effective decision-making of practitioners and academics. A number of studies have shown the existence of errors in proprietary databases provided by financial data aggregators (e.g., Compustat and Value Line) in advanced markets like the U.S. However, no study has examined the quality of the financial data offered by aggregators in emerging markets. Research on such markets is needed as financial investment frequently occurs in emerging markets due to the globalization of capital. The purpose of this study is to fill this gap by investigating whether financial data provided by aggregators is the same as the data reported in firms' financial statements in emerging markets. Another purpose of this study is to examine the impact on academic research. Comparing the 18 most widely-used financial items found in the original filings of firms with the corresponding data provided by all three data aggregators currently available in South Korea (i.e., DataGuide, KisValue, and TS2000), we found a considerable number of differences; many of the differences are substantially greater than conventional materiality. We also found that the differences between data sources lead to different prediction results in bankruptcy prediction model. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
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