34 results on '"Sun, Yongke"'
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2. Methods for processing and analyzing passive acoustic monitoring data: An example of song recognition in western black-crested gibbons
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Zhou, Xiaotao, Hu, Kunrong, Guan, Zhenhua, Yu, Chunjiang, Wang, Shuai, Fan, Meng, Sun, Yongke, Cao, Yong, Wang, Yijie, and Miao, Guangting
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- 2023
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3. Individual wood board tracing method using oriented fast and rotated brief method in the wood traceability system
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Sun, Yongke, Du, Guanben, Lin, Qizhao, Zhong, Lihui, Zhao, Youjie, Qiu, Jian, and Cao, Yong
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- 2022
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4. Log Volume Measurement and Counting Based on Improved Cascade Mask R-CNN and Deep SORT.
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Yu, Chunjiang, Sun, Yongke, Cao, Yong, Liu, Lei, and Zhou, Xiaotao
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STREAMING video & television ,FEATURE extraction ,VIDEO blogs ,VOLUME measurements ,ERROR rates - Abstract
Logs require multiple verifications to ensure accurate volume and quantity measurements. Log end detection is a crucial step in measuring log volume and counting logs. Currently, this task primarily relies on the Mask R-CNN instance segmentation model. However, the Feature Pyramid Network (FPN) in Mask R-CNN may compromise accuracy due to feature redundancy during multi-scale fusion, particularly with small objects. Moreover, counting logs in a single image is challenging due to their large size and stacking. To address the above issues, we propose an improved log segmentation model based on Cascade Mask R-CNN. This method uses ResNet for multi-scale feature extraction and integrates a hierarchical Convolutional Block Attention Module (CBAM) to refine feature weights and enhance object emphasis. Then, a Region Proposal Network (RPN) is employed to generate log segmentation proposals. Finally, combined with Deep SORT, the model tracks log ends in video streams and counts the number of logs in the stack. Experiments demonstrate the effectiveness of our method, achieving an average precision ( A P ) of 82.3, A P s of 75.3 for small, A P m of 70.9 for medium, and A P l of 86.2 for large objects. These results represent improvements of 1.8%, 3.7%, 2.6%, and 1.4% over Mask R-CNN, respectively. The detection rate reached 98.6%, with a counting accuracy of 95%. Compared to manually measured volumes, our method shows a low error rate of 4.07%. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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5. Network of Interactions between the Mut Domains of the E2 Protein of Atypical Porcine Pestivirus and Host Proteins.
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Yang, Yuai, Jiang, Guangfei, He, Weiqi, Tian, Xin, Zheng, Huanli, Xiang, Bin, and Sun, Yongke
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PROTEIN domains ,ANIMAL herds ,PROTEIN-protein interactions ,ENERGY metabolism ,AMINO acids - Abstract
Atypical porcine pestivirus (APPV) can cause congenital tremor type A-II in neonatal piglets, posing a significant threat to swine herd health globally. Our previous study demonstrated that the Mut domains, comprising 112 amino acids at the N-terminus, are the primary functional regions of the E2 protein of APPV. This study identified 14 host cellular proteins that exhibit potential interactions with the Mut domains of the E2 protein using yeast two-hybrid screening. Using bioinformatics analysis, we discovered that the Mut domains of the E2 protein might exert regulatory effects on apoptosis by modulating energy metabolism within the mitochondria. We also conducted co-immunoprecipitation, glutathione S-transferase pull-down, and immunofluorescence assays to confirm the interaction between the Mut domains of the E2 protein and cathepsin H and signal sequence receptor subunit 4 (SSR4). Ultimately, SSR4 enhanced APPV replication in vitro. In summary, our study successfully elucidated the interactions between the Mut domains of the E2 protein and host cell protein, predicted the potential pathways implicated in these interactions, and demonstrated SSR4 involvement in APPV infection. These significant findings contribute valuable knowledge toward a deeper understanding of APPV pathogenesis and the role of the Mut domains of the E2 protein in this intricate process. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Suitable Habitat Prediction and Analysis of Dendrolimus houi and Its Host Cupressus funebris in the Chinese Region.
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Miao, Guangting, Zhao, Youjie, Wang, Yijie, Yu, Chunjiang, Xiong, Fei, Sun, Yongke, and Cao, Yong
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CYPRESS ,GLOBAL warming ,HABITATS ,HOST plants ,WAREHOUSES - Abstract
The Dendrolimus houi, a phytophagous pest, displays a broad range of adaptations and often inflicts localized damage to its hosts. Cupressus funebris, an indigenous timber species in China, is significantly impacted by D. houi. Investigating the suitable habitat distribution and changes in D. houi and its host plant, C. funebris, within the context of climate warming, is essential for understanding D. houi's development and providing novel insights for managing D. houi and conserving C. funebris resources. In this study, MaxEnt was employed to simulate the distribution of D. houi and its host plant, C. funebris, in their suitable habitats, evaluating the influence of environmental factors on their distribution and determining changes under a warming scenario. MaxEnt model parameters were adjusted using the Kuenm data package based on available distribution and climatic data. The minimum temperature of the coldest month emerged as the primary environmental factor influencing the distribution of a suitable habitat for D. houi and C. funebris, with a percentage contribution of environmental factors over 60%. There was a substantial similarity in the suitable habitat distributions of D. houi and C. funebris, with varying degrees of expansion in the total habitat area under different temporal and climatic scenarios. Intersection analysis results indicated that the 2041–2060 period, especially under low (SSP1-2.6) and high (SSP5-8.5) emission scenarios, is a critical phase for D. houi control. The habitat expansion of D. houi and C. funebris due to climate change was observed, with the distribution center of D. houi shifting northeast and that of C. funebris shifting northwest. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Rubber Tree Recognition Based on UAV RGB Multi-Angle Imagery and Deep Learning.
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Liang, Yuying, Sun, Yongke, Kou, Weili, Xu, Weiheng, Wang, Juan, Wang, Qiuhua, Wang, Huan, and Lu, Ning
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- 2023
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8. Endogenous hydrogen sulfide formation mediates the liver damage in endotoxemic rats
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Yan, Yulin, chen, Chao, Zhou, Hui, Gao, Hong, Chen, Liping, Chen, Ling, Gao, Libo, Zhao, Ru, and Sun, Yongke
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- 2013
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9. Co-expression of Erns and E2 genes of classical swine fever virus by replication-defective recombinant adenovirus completely protects pigs against virulent challenge with classical swine fever virus
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Sun, Yongke, Yang, Yuai, Zheng, Huanli, Xi, Dongmei, Lin, Mingxing, Zhang, Xiaomin, Yang, Linfu, Yan, Yulin, Chu, Xiaohui, and Bi, Baoliang
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- 2013
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10. Individual Tree AGB Estimation of Malania oleifera Based on UAV-RGB Imagery and Mask R-CNN.
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Gong, Maojia, Kou, Weili, Lu, Ning, Chen, Yue, Sun, Yongke, Lai, Hongyan, Chen, Bangqian, Wang, Juan, and Li, Chao
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DEEP learning ,FOREST biomass ,CARBON cycle ,MIXED forests ,DRONE aircraft ,FOREST canopies - Abstract
Forest aboveground biomass (AGB) is an important research topic in the field of forestry, with implications for carbon cycles and carbon sinks. Malania oleifera Chun et S. K. Lee (M. oleifera) is a valuable plant species that is listed on the National Second-Class Protected Plant checklist and has received global attention for its conservation and resource utilization. To obtain accurate AGB of individual M. oleifera trees in a fast, low-finance-cost and low-labor-cost way, this study first attempted to estimate individual M. oleifera tree AGB by combining the centimeter-level resolution RGB imagery derived from unmanned aerial vehicles (UAVs) and the deep learning model of Mask R-CNN. Firstly, canopy area (CA) was obtained from the 3.5 cm high-resolution UAV-RGB imagery using the Mask R-CNN; secondly, to establish an allometric growth model between the diameter at breast height (DBH) and CA, the correlation analysis of both was conducted; thirdly, the AGB estimation method of individual M. oleifera trees was presented based on an empirical equation. The study showed that: (1) The deep learning model of Mask R-CNN achieved an average segmentation accuracy of 90% in the mixed forests to the extraction of the canopy of M. oleifera trees from UAV-RGB imagery. (2) The correlation between the extracted CA and field-measured DBH reached an R
2 of 0.755 (n = 96). (3) The t-test method was used to verify the predicted and observed values of the CA-DBH model presented in this study, and the difference in deviation was not significant (p > 0.05). (4) AGB of individual M. oleifera was estimated for the first time. This study provides a reference method for the estimation of individual tree AGB of M. oleifera based on centimeter-level resolution UAV-RGB images and the Mask R-CNN deep learning. [ABSTRACT FROM AUTHOR]- Published
- 2023
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11. A Novel Wood Log Measurement Combined Mask R-CNN and Stereo Vision Camera.
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Yu, Chunjiang, Sun, Yongke, Cao, Yong, He, Jie, Fu, Yixing, and Zhou, Xiaotao
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WOOD ,STEREOSCOPIC cameras ,SEARCH algorithms ,SAWLOGS - Abstract
Wood logs need to be measured for size when passing through customs to verify their quantity and volume. Due to the large number of wood logs needs through customs, a fast and accurate measurement method is required. The traditional log measurement methods are inefficient, have significant errors in determining the long and short diameters of the wood, and are difficult to achieve fast measurements in complex wood stacking environments. We use a Mask R-CNN instance segmentation model to detect the contour of the wood log and employ a binocular stereo camera to measure the log diameter. A rotation search algorithm centered on the wood contour is proposed to find long and short diameters and to optimal log size according to the Chinese standard. The experiments show that the Mask R-CNN we trained obtains 0.796 average precision and 0.943 I O U m a s k , and the recognition rate of wood log ends reaches 98.2%. The average error of the short diameter of the measurement results is 5.7 mm, the average error of the long diameter is 7.19 mm, and the average error of the diameter of the wood is 5.3 mm. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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12. Nucleotide diversity of the melanocortin 1 receptor gene (MC1R) in the gayal (Bos frontalis)
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Xi, Dongmei, Liu, Qing, Huo, Yinqiang, Sun, Yongke, Leng, Jing, Gou, Xiao, Mao, Huaming, and Deng, Weidong
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- 2012
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13. Molecular cloning, sequence identification and tissue expression profile of three novel genes Sfxn1, Snai2 and Cno from Black-boned sheep (Ovis aries)
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Xi, Dongmei, He, Yiduo, Sun, Yongke, Gou, Xiao, Yang, Shuli, Mao, Huaming, and Deng, Weidong
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- 2011
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14. Similar Pattern of Potential Distribution of Pinus yunnanensis Franch and Tomicus yunnanensis Kirkendall under Climate Change in China.
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Huang, Biaosheng, Mao, Jiawei, Zhao, Youjie, Sun, Yongke, Cao, Yong, and Xiong, Zhi
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PINE ,CURRENT distribution ,COLD (Temperature) ,ALTITUDES ,ENTROPY - Abstract
Tomicus yunnanensis Kirkendall (Coleoptera: Scolytinae) is a stem-boring pest that endangers Pinus yunnanensis Franch (Pinales:Pinoideae), which seriously affects the ecological environment safety in southwest China. In order to understand the potential distribution pattern and change in the potential distribution of P. yunnanensis and T. yunnanensis, this study used the maximum entropy model to predict the distribution of potentially suitable areas for P. yunnanensis and T. yunnanensis and explored the relationships between their different spatiotemporal distributions based on change analysis. The experimental results show that altitude is the main factor restricting the current distribution of P. yunnanensis. The current suitable areas of P. yunnanensis are mainly distributed in Yunnan, Sichuan and Guizhou. The minimum temperature of the coldest month is the main factor affecting the current distribution of T. yunnanensis. The current suitable areas of T. yunnanensis are mainly distributed in Yunnan, Sichuan and Tibet. Under future climate scenarios, the total suitable areas of P. yunnanensis and T. yunnanensis are expected to increase. The suitable areas tend to move to higher altitudes in the west and higher latitudes in the north. At the same time, this study finds that there is an obvious bottleneck of expansion to northeastern Sichuan near the Daba Mountains. The results of intersection analysis showed that, with future climate change, P. yunnanensis and T. yunnanensis mainly showed lowly suitable (or unsuitable)—lowly suitable (or unsuitable) to moderately (or highly) suitable—and moderate (or high) variation patterns of suitable areas under the SSP1-2.6 climate scenario. These results will provide an important basis for the breeding of P. yunnanensis and controlling T. yunnanensis. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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15. An Improved Wood Recognition Method Based on the One-Class Algorithm.
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He, Jie, Sun, Yongke, Yu, Chunjiang, Cao, Yong, Zhao, Youjie, and Du, Guanben
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WOOD ,SUPPORT vector machines ,ENDANGERED species ,MAGNIFYING glasses ,FEATURE extraction ,KALMAN filtering - Abstract
Wood recognition is necessary for work in the wood trade activities. The advantage of the one-class wood classification method is more generalization, and it only needs positive samples and does not need negative samples in the training phase, so it is suitable for rare wood species inspection. This paper proposed an improved method based on the one-class support vector machine (OCSVM) for wood species recognition. It uses cross-section images acquired with a magnifying glass, which uses a pre-trained VGG16 model for feature extraction, a normal distribution test for key features filtering, and OCSVM to determine the wood species. The results showed that the approach achieved a mean recall of 0.842 for both positive and negative samples, which indicates this method has good performance for wood recognition. In a negative public dataset, the negative recall reached as high as 0.989, which showed that this method has good generalization. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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16. A computer-aided method for identifying the presence of softwood growth ring boundaries.
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Lin, Qizhao, He, Tuo, Sun, Yongke, He, Xin, and Qiu, Jian
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SOFTWOOD ,IMAGE processing ,GEOGRAPHIC boundaries ,PLURALITY voting ,IMAGE analysis ,COMPUTER systems - Abstract
The objective of this study was to develop a computer-aided method to quantify the obvious degree of growth ring boundaries of softwood species, based on data analysis with some image processing technologies. For this purpose, a 5× magnified cross-section color micro-image of softwood was cropped into 20 sub-images, and then every image was binarized as a gray image according to an automatic threshold value. After that, the number of black pixels in the gray image was counted row by row and the number of black pixels was binarized to 0 or 100. Finally, a transition band from earlywood to latewood on the sub-image was identified. If everything goes as planned, the growth ring boundaries of the sub-image would be distinct. Otherwise would be indistinct or absent. If more than 50% sub-images are distinct, with the majority voting method, the growth ring boundaries of softwood would be distinct, otherwise would be indistinct or absent. The proposed method has been visualized as a growth-ring-boundary detecting system based on the.NET Framework. A sample of 100 micro-images (see S1 Fig via https://github.com/senly2019/Lin-Qizhao/) of softwood cross-sections were selected for evaluation purposes. In short, this detecting system computes the obvious degree of growth ring boundaries of softwood species by image processing involving image importing, image cropping, image reading, image grayscale, image binarization, data analysis. The results showed that the method used avoided mistakes made by the manual comparison method of identifying the presence of growth ring boundaries, and it has a high accuracy of 98%. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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17. Hole mobility in silicon inversion layers: Stress and surface orientation.
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Sun, Guangyu, Sun, Yongke, Nishida, Toshikazu, and Thompson, Scott E.
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METAL oxide semiconductor field-effect transistors , *FINITE differences , *EFFECTIVE mass (Physics) , *SILICON research , *SCALING laws (Statistical physics) - Abstract
Hole transport in the p-type metal-oxide-semiconductor field-effect-transistor (p-MOSFET) inversion layer under arbitrary stress, surface, and channel orientation is investigated by employing a six-band k·p model and finite difference formalism. The piezoresistance coefficients are calculated and measured at stresses up to 300 MPa via wafer-bending experiments for stresses of technological importance: uniaxial and biaxial stresses on (001) and (110) surface oriented p-MOSFETs with <110> and <111> channels. With good agreement in the measured and calculated small stress piezoresistance coefficients, k·p calculations are used to give physical insights into hole mobility enhancement at large stress (∼3 GPa). The results show that the maximum hole mobility is similar for (001)/<110>, (110)/<110>, and (110)/<111> p-MOSFETs under uniaxial stress, although the enhancement factor is different. Strong quantum confinement and a low density of states cause less stress-induced mobility enhancement for (110) p-MOSFETs. For (001) p-MOSFETs, the dominant factor for the improved hole mobility is reduced conductivity effective mass at small stress and lower phonon scattering rate at large stress. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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18. FrontMatter.
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Sun, Yongke, Thompson, Scott E., and Nishida, Toshikazu
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- 2010
19. Overview: The Age of Strained Devices.
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Sun, Yongke, Nishida, Toshikazu, and Thompson, Scott E.
- Abstract
One of the predecessors of strained Si to enhance MOSFET performance is the research that showed enhanced electron mobilities in n-type (100) Si/Si
1−x Gex multilayer heterostructures and hole mobilities in p-type (100) Si/i-Si1−x Gex /Si double-heterostructures in the early 1980s (Manasevit et al, 1982; R.People et al, 1984). Strain caused by the lattice mismatch was sus- pected as one of the factors for the mobility enhancement. The physical mech- anism for the enhancement can be traced back to the theoretical formulation of deformation potentials by Bardeen and Shockley (Bardeen and Shockley, 1950; Shockley and Bardeen, 1950) in 1950 and the experimental measure- ments of the piezoresistance effect, a change in resistance with mechanical stress, by Smith (Smith, 1954). In an era of rapidly changing technology, strain is a relatively old topic in semiconductor physics, yet its tangible effects on band structure and carrier transport have spurred a renewed interest in strained semiconductor physics. To model lattice scattering, deformation potential theory was developed by Bardeen and Shockley to characterize the band energy shift with strain caused by phonons (Bardeen and Shockley, 1950; Shockley and Bardeen, 1950). Herring and Vogt (Herring and Vogt, 1956) then extended deformation po- tentials to model transport in strained semiconductors. Deformation potential theory is still the primary method to model the band shift and warping in energy band calculations (Oberhuber et al, 1998; Fischetti and Laux, 1996). [ABSTRACT FROM AUTHOR]- Published
- 2010
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20. Stress, Strain, Piezoresistivity, and Piezoelectricity.
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Sun, Yongke, Nishida, Toshikazu, and Thompson, Scott E.
- Abstract
Strain in crystals is created by deformation and is defined as relative lattice displacement. For simplicity, we use a 2D lattice model in Fig.2.1 to illustrate this conception, but discuss the general conception in 3D cases. As shown in Fig. 2.1a, we may use two unit vectors ]> to represent the unstrained lattice, and in a simple square lattice, they correspond to the lattice basis vectors. Under a small uniform deformation of the lattice, the two vectors are distorted in both orientation and length, which is shown in Fig. 2.1b. The new vectors ]> and ]> may be written in terms of the old vectors: 2.1 ]> 2.2 ]> and in the 3D case, we also have 2.3 ]> [ABSTRACT FROM AUTHOR]
- Published
- 2010
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21. Strain and Semiconductor Crystal Symmetry.
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Sun, Yongke, Nishida, Toshikazu, and Thompson, Scott E.
- Abstract
One common question asked about strain on semiconductor band structures is: why is there band splitting with strain? Essentially, the answer to this question can only be sought from the semiconductor crystal symmetry considerations. Band degeneracies are defined by semiconductor crystal symmetry. When strain reduces the original symmetry, some degeneracies are lifted, and thus we see band splitting. Symmetry considerations are intuitively simple yet very complicated when treated in a systematical way. The mathematical tool to treat symmetry is group theory. In this chapter, we are going to investigate the semiconductor crystal symmetry and its effects on the semiconductor band structures, then study strain-altered symmetry-induced band splitting and warping. For simplicity, we will avoid use of the abstract concepts of group theory, but rather wil treat the relation of symmetry and properties of band structures using simple observations and examples. We will divide the discussion in this chapter into two main parts. The first part is for readers who want a simple qualitative picture of symmetry and its effects on band structures. Through the qualitative discussion alone, one can understand how strain changes the band structure by reducing the crystal symmetry. The second part is aimed for readers with an interest in more detailed yet more abstract conceptions and reasonings. Thus, this chapter is organized as follows: in Sect. 3.2, a qualitative discussion is first given for symmetry and its associated band properties; strain-induced symmetry reduction and band property alteration are illustrated using simple diagrams for qualitative understanding. Then in Sect. 3.3 and the following sections, detailed discussions of crystal symmetries are given. Symmetry-determined band properties are studied in a more theoretical point of view. In the last section, a summary is given, which discusses the merits and limitations of symmetry considerations in terms of the current strain research. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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22. Band Structures of Strained Semiconductors.
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Sun, Yongke, Nishida, Toshikazu, and Thompson, Scott E.
- Abstract
In Chap. 3, a qualitative picture of band splitting and warping under stress, e.g., as shown in Figs. 3.9–3.11, was obtained merely from symmetry considerations. But for application purpose in strain engineering, further band structure details with strain are required. Otherwise, it is not possible to determine which type of stress is advantageous for a specific application goal. That is, symmetry alone cannot provide enough information that we have to acquire before we can implement the desirable stress. For example, 〈110❭ uniaxial stress, no matter tensile or compressive, will result in the same symmetry lowering to a cubic crystal. As in Fig. 3.10, the x-y plane energy contour, which has an ellipse shape resulting from the compressive 〈110❭ uniaxial stress, could have its major axis either in the [110] direction or in the [110] direction, both complying with the uniaxial stress symmetry. Symmetry alone is not adequate to determine along which direction the ellipse major axis is oriented. However, this knowledge is critical for strain applications in n-type Si MOSFETs. Similar situations also exist in the valence bands. The band warping and splitting details, which are crucial for strain to enhance the p-type MOSFET performance, are not decisively determined by stress symmetry. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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23. Low-Dimensional Semiconductor Structures.
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Sun, Yongke, Nishida, Toshikazu, and Thompson, Scott E.
- Abstract
In the last chapter, we have introduced the theories for calculating the band structures of bulk semiconductors and discussed the corresponding strain effects. However, carriers in most modern electron devices such as FETs are electrically or spatially confined. Confinement interrupts the periodic potential where an electron in a bulk semiconductor has. Quantum mechanically, electric confinement and spatial confinement have no essential difference. They alter the potential term V (r) in the single electron Schröinger equation (3.1) such that in the confinement direction(s), the potential loses the periodic characteristic the bulk crystals possess. This has significant effects on carrier transport properties, since electron systems are distinguished by this very potential term V (r), as discussed in Chap. 3. Typical confined electron systems include quantum wells, quantum wires, and quantum dots, which are 2D, 1D, and 0D structures, respectively. A MOSFET is a symbolic 2D electron system, which invention is probably the most important event in the history of modern semiconductor industry, and has been the locomotive for the technology development for half a century. The operation of a MOSFET is based on the control of the electronic behavior through tunable external electric field to create a 2D electron gas (2DEG) layer close to the semiconductor/oxide interface. Structural 2D systems such as quantum wells extend the means of 2DEG generation and present extensive research interest and electrical and optical applications as well, especially when the crystal growth techniques such as molecular beam epitaxy are very mature nowadays. Quantum wells can be created by growing a layer of semiconductor sandwiched by two semiconductor layers whose band gaps are larger than the former, or formed in a heterojunction such as GaAs/Ga
1−x Alx As. The former sandwich structures are extensively found in quantum well lasers. The GaAs/Ga1−x Alx As heterojunction is the kernel part for a high electron mobility field effect transistor (HEMFET) since the similar lattice constant and coefficient of expansion of Ga1−x Alx As permits the growth of high mobility thin Ga1−x Alx As film on a GaAs substrate. With aggressive scaling of modern planar MOSFET devices, short channel effects become increasingly grave. Other device architectures such as fully depleted silicon-on-insulator (SOI), double-gate MOSFET, and FinFET devices are currently under intense investigation. Conceptual devices using carbon nanotubes and Si-nanowires also present promising application prospects. A Si-nanowire with transverse cross section length scale in nanometer scale is typically 1D structure. The motion of electrons is restricted along the nanowire and quantized in the transverse directions. In these nontraditional semiconductor structures, both electric and spatial confinement are present and often interact with each other. [ABSTRACT FROM AUTHOR]- Published
- 2010
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24. Semiconductor Transport.
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Sun, Yongke, Nishida, Toshikazu, and Thompson, Scott E.
- Abstract
Performance of electron devices such as MOSFETs is characterized by parameters such as mobility, transconductance, leakage current, etc. These parameters are some particular aspects or concrete representation of carrier transport properties in semiconductor structures. Device performance enhancement by strain is rooted from strain altered carrier transport properties. Based on the band structures we discussed in earlier chapters, we will discuss some basic transport models in this chapter to understand how strain changes electron/hole transport, to reach theoretical understanding of strain effects on device performance. First in Sect. 6.2 a qualitative overview is given for readers who want just to dabble in transport theories and strainenhanced mobility in Si MOSFETs. Then in Sects. 6.3 and 6.4 we discuss the various scattering mechanisms in semiconductors and construct a general formulation to treat scattering processes. Boltzmann equation is introduced afterward in Sect. 6.5 to calculate the carrier mobility. In low-dimensional semiconductor structures, scattering processes are significantly different from that of bulk. The new features of scattering in 2D systems are particularly discussed in Sect. 6.6. The strain effects on transport are discussed and summarized in Sect. 6.7. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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25. Strain in Electron Devices.
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Sun, Yongke, Nishida, Toshikazu, and Thompson, Scott E.
- Abstract
Today΄s strain-Si technology has been based on the physics of strain effects on bulk and low-dimensional band structures and carrier transport. Although the strain effects on bulk semiconductors have been studied since the 1950s, and the effects on Si MOSFETs have been discovered and studied since 1980s, strain has never really been adopted in mainstream Si CMOS technology until 2002s by Intel, because before then, the speed of the VLSI/ULSI chips could be boosted just by geometrical scaling, i.e., increasing the transistor density, which now numbers typically at ~10
9 in a single chip, by shrinking the transistor size. However, this comes with price. Short channel effects significantly degrade the device performance when the transistor size is too small, and the leakage current results in large power dissipation, then the traditional scaling reaches a bottleneck. Strain then as a ˵performance adder″ is eventually adopted. Today, the chips with strained-Si devices (see Fig. 7.1) serve the three dominant markets of computer, communication and consumer electronics and highlight the wide success of this technology in not only high performance but also low cost markets. [ABSTRACT FROM AUTHOR]- Published
- 2010
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26. Piezoresistive Strain Sensors.
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Sun, Yongke, Nishida, Toshikazu, and Thompson, Scott E.
- Abstract
In contrast to the fixed strain incorporated in logic devices for a fixed or constant improvement in device performance, piezoresistive strain sensors respond to variable strain through a modulation in the device resistance. The underlying physics of performance improvement in logic devices and strain transduction in piezoresistive strain sensors is the same: symmetry-breaking strain of the semiconductor crystal lattice warps the energy bands, splits the energy levels, and changes the carrier scattering rates, which changes the carrier mobility and the device resistance. While improvement of logic device performance requires an increase in mobility, which dictates the ˵sign″ of the fixed strain, strain sensors respond to both negative (compressive) and positive (tensile) strains. Since the strain is fixed in logic devices, the linearity of mobility increase with strain is not an issue since the strain is theoretically frozen into the device by stressors incorporated into the device structure during the manufacturing process. In contrast, piezoresistive strain sensors are designed to transduce or detect varying strains by producing a proportional change in resistance. Hence, linear resistance change with strain is important to sense/transduce strains of varying amplitudes into an electrical signal without introducing distortion. For a transducer, the measured resistance vs. strain curve can be used to calculate the input strain from the strain sensitivity or calibration slope of the sensor. For a piezoresistive strain sensor, the upper limit of the measurable strain is usually defined as the maximum strain abovewhich nonlinear deformation occurs. In contrast, there is no maximum allowable stress in strain-enhanced logic devices as long as there is performance enhancement, provided that the stress is manufacturable and the device is reliable. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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27. BackMatter.
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Sun, Yongke, Thompson, Scott E., and Nishida, Toshikazu
- Published
- 2010
28. Strain Effects on Optoelectronic Devices.
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Sun, Yongke, Nishida, Toshikazu, and Thompson, Scott E.
- Abstract
Optoelectronics has become an essential part of modern lives in computer, consumer electronics, and communication. Optoelectronic devices either generate light or utilize light in their operation. Typical examples include light-emitting diodes in remote controls, battery chargers, even traffic lights, photodetectors in alarms, digital cameras, radars, and lasers in labs and barcode scanners in stores. Optoelectronics is based on the quantum mechanical interactions between light and matter, which in most cases are semiconducting materials. In these interactions, photons as energy quanta of the light are either emitted or absorbed. These two basic quantum processes are similar to the phonon transition processes in semiconductors, involving two electronic states with conservation of both energy and momentum. The energy of a photon is determined by its wavelength λ, E = hc/λ, where h is the Plank constant and c is the speed of light, and its momentum is given by h/λ. Photon energies for the visible light are between 2 and 3 eV, which is the range of semiconductor bandgaps, with their wavelengths between 4000 and 7000 Å. Compared to the electron momentum hk in a solid, where k is the electron wave vector and in the order of Π/a, where a is the lattice constant around the order of several Å, the typical momentum of a photon is very small. Therefore, the photon transitions between electronic states in solids are considered ˵vertical.″ That is to say, the electron momentum change for photon transitions in the Brillouin zone is often neglected, unlike the phonon processes. Also, phonons do not have angular momentum, but photons generally have definite polarization configuration and carry specific angular momentum, and thus angular momentum conservation has to be complied in photon transitions. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
29. A miRNA Target Prediction Model Based on Distributed Representation Learning and Deep Learning.
- Author
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Sun, Yuzhuo, Xiong, Fei, Sun, Yongke, Zhao, Youjie, and Cao, Yong
- Subjects
- *
DEEP learning , *NON-coding RNA , *NUCLEOTIDE sequence , *MICRORNA , *MESSENGER RNA , *PREDICTION models , *LINCRNA - Abstract
MicroRNAs (miRNAs) are a kind of noncoding RNA, which plays an essential role in gene regulation by binding to messenger RNAs (mRNAs). Accurate and rapid identification of miRNA target genes is helpful to reveal the mechanism of transcriptome regulation, which is of great significance for the study of cancer and other diseases. Many bioinformatics methods have been proposed to solve this problem, but the previous research did not further study the encoding of the nucleotide sequence. In this paper, we developed a novel method combining word embedding and deep learning for human miRNA targets at the site-level prediction, which is inspired by the similarity between natural language and biological sequences. First, the word2vec model was used to mine the distribution representation of miRNAs and mRNAs. Then, the embedding is extracted automatically via the stacked bidirectional long short-term memory (BiLSTM) network. By testing, our method can effectively improve the accuracy, sensitivity, specificity, and F -measure of other methods. Through our research, it is proved that the distributed representation can improve the accuracy of the deep learning model and better solve the miRNA target site prediction problem. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
30. Between disorder and order: A case study of power law.
- Author
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Cao, Yong, Zhao, Youjie, Yue, Xiaoguang, Xiong, Fei, Sun, Yongke, He, Xin, and Wang, Lichao
- Subjects
- *
POWER law (Mathematics) , *THERMODYNAMICS , *STATISTICAL physics , *ENTROPY , *EQUILIBRIUM , *BIOLOGICAL systems - Abstract
Power law is an important feature of phenomena in long memory behaviors. Zipf ever found power law in the distribution of the word frequencies. In physics, the terms order and disorder are Thermodynamic or statistical physics concepts originally and a lot of research work has focused on self-organization of the disorder ingredients of simple physical systems. It is interesting what make disorder–order transition. We devise an experiment-based method about random symbolic sequences to research regular pattern between disorder and order. The experiment results reveal power law is indeed an important regularity in transition from disorder to order. About these results the preliminary study and analysis has been done to explain the reasons. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
31. Induction of ROS generation and NF-κB activation in MARC-145 cells by a novel porcine reproductive and respiratory syndrome virus in Southwest of China isolate.
- Author
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Yan Y, Xin A, Liu Q, Huang H, Shao Z, Zang Y, Chen L, Sun Y, and Gao H
- Subjects
- Animals, Cell Line, China epidemiology, Gene Expression Regulation physiology, Genome, Viral, Haplorhini, NF-kappa B genetics, Porcine Reproductive and Respiratory Syndrome epidemiology, Swine, NF-kappa B metabolism, Porcine Reproductive and Respiratory Syndrome virology, Porcine respiratory and reproductive syndrome virus physiology, Reactive Oxygen Species metabolism
- Abstract
Background: Porcine reproductive and respiratory syndrome virus (PRRSV) is the cause of an economically important swine disease that has devastated the swine industry since the late 1980s. The aim of the present study was to investigate the interaction between reactive oxygen species (ROS) and NF-κB by PRRSV infection., Results: We isolated the local strain of PRRSV from southwest China, designated YN-2011, then sequenced and analyzed the genome. YN-2011 was then used to evaluate the interaction of ROS and NF-κB. In PRRSV infected MARC-145 cells, there was a time-dependent increase in ROS and Maleic Dialdehyde (MDA). Accordingly, NF-κB activation was also increased as PRRSV infection progressed. Degradation of IκB mRNA was detected late in PRRSV infection, and overexpression of the dominant negative form of IκBα significantly suppressed NF-κB induced by PRRSV., Conclusions: The results indicate that the generation of ROS is involved in PRRSV replication and this progression is associated with the alteration in NF-κB activity induced by ROS. These results should extend our better understanding the interaction between PRRSV and host MARC-145 cells.
- Published
- 2015
- Full Text
- View/download PDF
32. Isolation and cDNA characteristics of MHC-DRA genes from gayal ( Bos frontalis ) and gaytle ( Bos frontalis × Bos taurus ).
- Author
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Sun Y, Zhang X, Xi D, Li G, Wang L, Zheng H, Du M, Gu Z, Yang Y, and Yang Y
- Abstract
The mammalian major histocompatibility complex (MHC) plays important roles in pathogen recognition and disease resistance. In the present study, the coding sequence and the 5'- and 3'-untranslated regions of MHC class II DR alpha chain (the DRA gene) from rare gayal and gaytle were cloned and analyzed to dissect structural and functional variations. The nucleotide and amino acid sequences for the DRA genes in gayal ( Bofr-DRA ) and gaytle ( Bofr × BoLA-DRA ) were almost identical to those for cattle and yak (99%). Compared to yak, two amino acids substitutions in the signal peptide (SP) domain for gayal were found within all Bos animals. Except for only one replacement in the amino acid within the α2 domain of the DRA protein in gayal, the additional residues were highly conserved across the species investigated. The 20 peptide-binding sites (PBS) of Bofr-DRA and Bofr × BoLA-DRA were essentially reserved in the α1 domain among all species investigated. The lesser degree of substitution in Bofr-DRA is concordant with the concept that the DRA gene is highly conserved among all mammals. The very high degree of conservativity of the DRA gene among ruminants, including gayal, suggests its recent evolutionary separation.
- Published
- 2015
- Full Text
- View/download PDF
33. Genetic characterization of MHC class II DQB exon 2 variants in gayal ( Bos frontalis ).
- Author
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Sun Y, Xi D, Li G, Hao T, Chen Y, and Yang Y
- Abstract
In the present study, exon 2 of major histocompatibility complex (MHC) class II DQB gene from 39 gayals ( Bos frontalis ) was isolated, characterized and compared with previously reported patterns for other bovidae. It was revealed by sequence analyses that there are 36 DQB exon 2 variants among 39 gayals. These variants exhibited a high degree of nucleotide and amino acid substitutions with most amino acid variations occurring at positions forming the peptide-binding sites (PBS). The DQB loci were analysed for patterns of synonymous ( d
S ) and non-synonymous ( dN ) substitution. The gayals were observed to be under strong balancing selection in the DQB exon 2 PBS ( dN = 0.094, P = 0.001). It appears that this variability among gayals could confer the ability to mount immune responses to a wide variety of peptides or pathogens.- Published
- 2014
- Full Text
- View/download PDF
34. Complete genome sequence of a novel natural recombinant porcine reproductive and respiratory syndrome virus isolated from a pig farm in yunnan province, southwest china.
- Author
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Yan Y, Xin A, Zhu G, Huang H, Liu Q, Shao Z, Zang Y, Chen L, Sun Y, and Gao H
- Published
- 2013
- Full Text
- View/download PDF
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