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Aiming at the problems of information disconnection and business interruption in supply chain networks caused by uncertainties such as trade wars and COVID-19, a projection-transformation-based model for predicting possible collaborative relationship links in bimodal supply chain networks is designed from the perspective of network science. The model first transforms the bimodal network structure of supply chain into a corresponding unimodal projection network by projection transformation; then screens the candidate collaborative links in the network; finally assigns weights to the similarity links according to different influencing factors, and calculates the possibility of potential collaborative links in the bimodal supply chain network by this. The experimental results show that the model can achieve higher quality prediction in real bimodal supply chain networks compared with other baseline link prediction models, which provides theoretical and methodological support for better formulation of business contingency plans and risk defense measures. [ABSTRACT FROM AUTHOR]

In view of the matching problem between objects and mirrors in images, the RNFA(Relative Number of False Alarms)edge chain detection method is introduced to obtain richer line segments. An improved LBD(Line Band Descriptor) algorithm is proposed for constructing local invariant feature descriptors, and initial matching pairs are obtained by comparing local invariant feature descriptors. The screening of the global projection angle is adopted and the false matches in the initial matching pairs are eliminated fitting the projection center line. After the selection of the global projection angle and the fitting of the projection median are completed, the screening of the local invariant feature descriptor threshold is relaxed to obtain more matching pairs and improve the recall rate. The experimental results of image set simulation show that the designed algorithm can better identify line segments in the weaker texture regions and obtain more matching pairs on the basis of the guaranteed performance of the original algorithm, which can improve the correct matching rate by about 5% and achieve a recall rate of over 90%. [ABSTRACT FROM AUTHOR]

Background: Add-on devices with projections, e.g., Endocuff, Endocuff Vision, EndoRings, and Wingcap, placed on the distal tip of the colonoscope promise to improve the detection of precancerous lesions. We performed a meta-analysis to evaluate the performance of these devices exclusively among individuals undergoing colonoscopy for screening purpose. Methods: A computerized literature search was performed across MEDLINE and Cochrane Library databases for randomized controlled trials that compared standard colonoscopy (SC) to procedures using add-on devices. The primary outcome was adenoma detection rate (ADR), while secondary outcomes included polyp detection rate (PDR), advanced ADR (AADR), and sessile serrated lesion detection rate (SSLDR). The effect size on study outcomes was calculated using a random-effects model and presented as the risk ratio (RR) and 95% confidence interval (CI). Results: Seven studies enrolling a total of 5785 patients were included. The use of add-on-devices with projections was associated with a higher ADR compared to SC: 45.9% vs. 41.1%; RR 1.18, 95%CI 1.02-1.37; P=0.03; χ2=79%. Although PDR was higher in screening colonoscopies assisted by add-on devices as compared to SC, the difference failed to reach significance: 55.1% vs. 50.8%; RR 1.10, 95%CI 0.96-1.26; P=0.17; χ2=75%. No difference was found between procedures assisted by add-on devices with projections and SC colonoscopies in terms of AADR (18.5% vs. 17.6%; RR 1.00, 95%CI 0.79-1.27; P=0.98; χ2=56%) or SSLDR (6.8% vs. 5.8%; RR 1.17, 95%CI 0.95-1.44; P=0.15; I2=0%). Conclusion: Colonoscopy assisted by add-on devices with projections achieves a better ADR compared to SC among individuals undergoing screening for bowel cancer. [ABSTRACT FROM AUTHOR]

Copyright of Área Abierta is the property of Universidad Complutense de Madrid 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.)

Are leaders made or born? Leader–follower roles have been well characterized in social science, but they remain somewhat obscure in sensory-motor coordination. Furthermore, it is unknown how and why leader–follower relationships are acquired, including innate versus acquired controversies. We developed a novel asymmetrical coordination task in which two participants (dyad) need to collaborate in transporting a simulated beam while maintaining its horizontal attitude. This experimental paradigm was implemented by twin robotic manipulanda, simulated beam dynamics, haptic interactions, and a projection screen. Clear leader–follower relationships were learned only when strong haptic feedback was introduced. This phenomenon occurred despite participants not being informed that they were interacting with each other and the large number of equally-valid alternative dyadic coordination strategies. We demonstrate the emergence of consistent leader–follower relationships in sensory-motor coordination, and further show that haptic interaction is essential for dyadic co-adaptation. These results provide insights into neural mechanisms responsible for the formation of leader–follower relationships in our society. [ABSTRACT FROM AUTHOR]

In order to improve the accuracy of multi-projection correction fusion, a multi-projection correction method based on binocular vision is proposed. To date, most of the existing methods are based on the single-camera mode, which may lose the depth information of the display wall and may not accurately obtain the details of the geometric structure of the display wall. The proposed method uses the depth information of a binocular camera to build a high-precision 3D display wall model; thus, there is no need to know the specific CAD size of the display wall in advance. Meanwhile, this method can be applied to display walls of any shape. By calibrating the binocular vision camera, the radial and eccentric aberration of the camera can be reduced. The projector projects the encoded structured light stripes, and the high-precision 3D structural information of the projection screen can be reconstructed according to the phase relationship after collecting the deformation stripes on the projection screen with the binocular camera. Thus, the screen-projector sub-pixel-level mapping relationship is established, and a high-precision geometric correction is achieved. In addition, by means of the one-to-one mapping relation between the phase information and the three-dimensional space points, accurate point cloud matching among multiple binocular phase sets could be established, so that such method can be applied to any quantity of projectors. The experimental results based on various special-shaped projection screens show that, comparing to the single-camera-based method, the proposed method improves the geometric correction accuracy of multi-projection stitching by more than 20%. This method also has many advantages, such as strong universality, high measurement accuracy, and rapid measurement speed, which indicate its wide application potential in many different fields. [ABSTRACT FROM AUTHOR]

In order to clarify the quantitative relationship between students' visual clarity, comfort, and environmental brightness in the light environment of multimedia classrooms in colleges and universities and obtain the threshold and influence trends of brightness, visual clarity, and visual comfort in the light environment of the multimedia classroom, this paper proposes the research on the relevant influence parameters of the light environment of the multimedia classroom. Based on the analysis of the current situation of multimedia use in China, this paper proposes taking brightness as the main parameter of indoor light environment evaluation to carry out students' subjective evaluation experiments. The brightness range that can reflect the visual clarity and visual comfort of the experimenter is extracted by using multimedia combined with screen projection and HDRI technology. Finally, by analyzing the experimental data, combined with the operational definition of the psychophysical threshold, the functional relationship between visual clarity, comfort, and brightness in the light environment of a multimedia classroom is obtained through regression analysis and the threshold and extreme point data are calculated. The experimental results show that when the brightness range is 370.83 cd/m2 ≤ X ≤ 558.47 cd/m2, it has better visual clarity and visual comfort. When the brightness contrast is close to 10 : 1, the visual clarity is the highest; when the brightness contrast is close to 5 : 1, the visual comfort is the highest and decreases on both sides with the change in its value. Conclusion. The results of this experimental study can provide a basis for formulating and revising relevant laws and regulations in the future and provide a reference for the light environment design of multimedia classrooms in China. [ABSTRACT FROM AUTHOR]

Copyright of ANIAV: Revista de Investigación en Artes Visuales is the property of Universidad Politecnica de Valencia 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.)

Copyright of Fonseca: Journal of Communication is the property of Revista Fonseca Journal of Communication 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.)

The real-time rendering of large-scale terrain scenes has been a challenge and is a popular research topic in the fields of 3D games and virtual reality. To fully utilize GPU features, this paper proposes a real-time rendering algorithm for large-scale regular grid terrain based on GPU Tessellation. The CPU processes a coarse-grained quadtree to generate terrain patches and then passes the patches to the GPU after view culling. Then, the GPU refines the terrain by using GPU Tessellation and displacement mapping. The most important advantage of our method is that during the tessellation stage, a new rule that the distance, screen space projection error and variance of the height, as the standard of terrain roughness, is designed. During the tessellation stage, the distance, screen space projection error and variance of the height, as the standard of terrain roughness, are considered. The experimental results show that our algorithm can greatly reduce the CPU processing time and main memory space requirement, and fully utilize the new features of the GPU; In conclusion, the proposed approach can render large-scale terrain with high-precision in real-time. [ABSTRACT FROM AUTHOR]

The temporal occlusion paradigm is often used in anticipation and decision-making research in sports. Although it is considered as a valid measurement tool, evidence of its reproducibility is lacking but required for future cross-sectional and repeated-measures designs. Moreover, only a few studies on decision making in real-world environments exist. Here, we aimed at (a) implementing a temporal occlusion test with multi-dimensional motor response characteristics, and (b) assessing intra- and inter-session item reliability. Temporally occluded videos of attack sequences in a team handball scenario were created and combined with the SpeedCourt® contact plate system. Participants were instructed to perform pre-specified defensive actions in response to the video stimuli presented on a life-size projection screen. The intra- and inter-session (after at least 24 h) reproducibility of subjects' motor responses were analyzed. Significant Cohen's (0.44–0.54) and Fleiss' (0.33–0.51) kappa statistics revealed moderate agreement of motor responses with the majority of attack situations in both intra- and inter-session analyses. Participants made faster choices with more visual information about the opponents' unfolding action. Our findings indicate reliable decisions in a complex, near-game test environment for team handball players. The test provides a foundation for future temporal occlusion studies, including recommendations for new explanatory approaches in cognition research. [ABSTRACT FROM AUTHOR]

Compared to single source systems, stereo X-ray CT systems allow acquiring projection data within a reduced amount of time, for an extended field-of-view, or for dual X-ray energies. To exploit the benefit of a dual X-ray system, its acquisition geometry needs to be calibrated. Unfortunately, in modular stereo X-ray CT setups, geometry misalignment occurs each time the setup is changed, which calls for an efficient calibration procedure. Although many studies have been dealing with geometry calibration of an X-ray CT system, little research targets the calibration of a dual cone-beam X-ray CT system. In this work, we present a phantom-based calibration procedure to accurately estimate the geometry of a stereo cone-beam X-ray CT system. With simulated as well as real experiments, it is shown that the calibration procedure can be used to accurately estimate the geometry of a modular stereo X-ray CT system thereby reducing the misalignment artifacts in the reconstruction volumes. [ABSTRACT FROM AUTHOR]

Ordinary projection screen is not sensitive to interaction, it cannot meet the demands of teaching, virtual reality, and other applications. Due to the fact that people always use hands to complete a variety of human–computer interaction, the finger-based interactive projection technology is worth being researched. In this paper, an ordinary monocular camera is used to acquire video frame on projection screen, and the touch signal of finger in frame is used as the input of interactive projection system. Because the differences between spatial frequency of common digital camera and the projection screen is small, the frame obtained from camera will contain moire fringe, which needs to be filtered in image frequency domain. Then the difference between current frame edge and previous frame edge is calculated to obtain moving object edge clues. According to these clues, the most possible contour curve is searched in current frame edge, and the curve is fitted by polynomial approximation method. Its curvature integration is used to match with the curvature integration of finger template curve. After that the fingers in the curve are recognized. Because color information is not needed, this method can be used to recognize gloved fingers. Finally, finger shadow is used to judge whether the finger touches projection screen to complete interactive process. The experiments of writing and collaboratively rotating picture on projector screen show that this method can effectively complete interactive operation with the projection screen and can realize the multi-user operation. [ABSTRACT FROM AUTHOR]

In recent years, many scientific and industrial centres in the world developed virtual reality systems or laboratories. At present, among the most advanced virtual reality systems are CAVE-type (Cave Automatic Virtual Environment) installations. Such systems usually consist of four, five, or six projection screens arranged in the form of a closed or hemi-closed space. The basic task of such systems is to ensure the effect of user "immersion" in the surrounding environment. The effect of user "immersion" into virtual reality in such systems is largely dependent on optical properties of the system, especially on quality of projection of three-dimensional images. In this paper, techniques of projection of three-dimensional (3D) images in CAVE-type virtual reality systems are analysed. The requirements of these techniques for such virtual reality systems are outlined. Based on the results of measurements performed in a unique CAVE-type virtual reality laboratory equipped with two different 3D projection techniques, named Immersive 3D Visualization Lab (I3DVL), that was recently opened at the Gdańsk University of Technology, the stereoscopic parameters and colour gamut of Infitec and Active Stereo stereoscopic projection techniques are examined and discussed. The obtained results enable to estimate the projection system quality for application in CAVE-type virtual reality installations. [ABSTRACT FROM AUTHOR]

The exhibition of pairs of movies (double features) is no longer common at indoor theatres, but remains so at drive-in theatres. Given that most drive-ins have either one or two screens, they need to be more focused in their exhibition choices than indoor theatres and multiplexes that have many screens. To understand the film-programming choices of drive-ins, I collected data on the films exhibited at drive-ins during the summer of 2015. Most double features were new releases or, at least, films released within the last 30 days. When drive-ins exhibited double features they typically placed the new release first - presumably as it would be the movie patrons would be most interested in seeing. Drive-ins with two screens typically only offered a new release along with a less recent release on one screen as part of a double feature, and two less recent releases on the other screen. Drive-ins also tend to pair movies with similar ratings together. If a movie with a higher rating is paired with a movie of a lower rating, the more "adult" movie appears second. This is likely an attempt to make the first offering more family friendly. [ABSTRACT FROM AUTHOR]

Projectors have become a widespread tool to share information in Human-Robot Interaction with large groups of people in a comfortable way. Finding a suitable vertical surface becomes a problem when the projector changes positions when a mobile robot is looking for suitable surfaces to project. Two problems must be addressed to achieve a correct undistorted image: (i) finding the biggest suitable surface free from obstacles and (ii) adapting the output image to correct the distortion due to the angle between the robot and a nonorthogonal surface. We propose a RANSAC-based method that detects a vertical plane inside a point cloud. Then, inside this plane, we apply a rectangle-fitting algorithm over the region in which the projector can work. Finally, the algorithm checks the surface looking for imperfections and occlusions and transforms the original image using a homography matrix to display it over the area detected. The proposed solution can detect projection areas in real-time using a single Kinect camera, which makes it suitable for applications where a robot interacts with other people in unknown environments. Our Projection Surfaces Detector and the Image Correction module allow a mobile robot to find the right surface and display images without deformation, improving its ability to interact with people. [ABSTRACT FROM AUTHOR]

Illusory self-motion (vection) can be generated by visual stimulation. The purpose of the present study was to compare behavioral vection measures including intensity ratings, duration, and onset time across different visual display types. Participants were exposed to a pattern of alternating black-and-white horizontal or vertical bars that moved either in vertical or horizontal direction, respectively. Stimuli were presented on four types of displays in randomized order: (a) large field of view dome projection, (b) combination of three computer screens, (c) single computer screen, (d) large field of view flat projection screen. A Computer Rod and Frame Test was used to measure field dependence, a cognitive style indicating the person's tendency to rely on external cues (i.e., field dependent) or internal cues (i.e., field independent) with respect to the perception of one's body position in space. Results revealed that all four displays successfully generated at least moderately strong vection. However, shortest vection onset, longest vection duration, and strongest vection intensity showed for the dome projection and the combination of three screens. This effect was further pronounced in field independent participants, indicating that field dependence can alter vection. [ABSTRACT FROM AUTHOR]

Flat surfaces in our living environment to be used as replacements of a projection screen are not necessarily white. We propose a perceptual radiometric compensation method to counteract the effect of color projection surfaces on image appearance. It reduces color clipping while preserving the hue and brightness of images based on the anchoring property of human visual system. In addition, it considers the effect of chromatic adaptation on perceptual image quality and fixes the color distortion caused by non-white projection surfaces by properly shifting the color of the image pixels toward the complementary color of the projection surface. User ratings show that our method outperforms the existing methods in 974 out of 1020 subjective tests. [ABSTRACT FROM PUBLISHER]

Context: Virtual Microscopy. Aim: The aim of this study was to demonstrate, as a proof of concept, the integration of a Foldscope, along with a smartphone and screen mirroring devices, into the regular academic teaching program for use with all types of regular slides for economical virtual microscopy. Setting, Design & Methods: For the purpose of this demonstration, a microscopic slide of a ground section of a tooth, a smartphone (iPhone6), a Foldscope and an Apple TV module were chosen to demonstrate the integration of a low-cost unbreakable microscope along with a smartphone to facilitate immediate viewing, capture, sharing and even projection of the image by screen mirroring, if required, in a classroom setting. Conclusion: The Foldscope microscope (Foldscope Instruments, Palo Alto, CA, USA) invented by Manu Prakash is an extremely economical, Origami style, fold to assemble microscope available from popular online retailers at approximately Rupees 500 aimed at simplifying and enabling diagnostics and education worldwide. The Foldscope, integrated with a smartphone, allows for easy screen casting thus proving invaluable as an educational tool by creating an effortless bridge between analogue input and digital output, facilitating instant digitization of slides for viewing, display, communication and storage. This article demonstrates the use of the Foldscope for virtual microscopy in a classroom scenario, by employing the screen mirroring capabilities of a smartphone. [ABSTRACT FROM AUTHOR]

A numerical model was developed to design a new automotive low-beam light-emitting diode (LED) headlamp. First, an existing automotive low-beam projector LED headlamp model with ray-tracing software (TracePro) was simulated. The existing commercially available automobile LED headlamp is a combination of one multi-reflector and two projection systems serving as a lowbeam LED headlamp module. The simulated results were compared with the headlamp regulations to prove that the headlamp numerical model and boundary conditions were correct and similar to reality. Finally, the original design was modified into only two projection systems using singlelight- output 515 lumen LEDs. Each projection system was improved to make the headlamp light distributions conform to the ECE R112 regulation. It was concluded that using a high power LED could decrease the number of optical systems required for an automotive headlamp. [ABSTRACT FROM AUTHOR]

The development of a national audiovisual industry into a domestic and Ibero-American market scope in diverse exhibit screens, for the main ten countries of Unasur, faces new limitations and possibilities in a digitized and global environment. This is an analysis on the results of the five-year period 2010-2014, in terms of film premieres, public assistance, and the relationship among exhibited films by country of origin. The availability of various formats is addressed, and also the policies about Virtual Print Fee and screen quotas, in an unresolved integration of mechanisms for cooperation and joint regulation that effectively impact on the diversity offered and the consumption habits. [ABSTRACT FROM AUTHOR]

The development and application of computer technologies have allowed presentation support systems to be realized for a variety of purposes. In addition, globalization has increased the importance of non-native language presentations. The design of a presentation support system needs to take into account the differences between native and non-native speakers. To investigate such a design, twenty-two graduate students participated in a scenario-based experiment using an observation system. The results show that (1) the speaking volume of Chinese students as non-native speakers may differ than that of native speakers, (2) the height and eye rotation of the participants may influence the change in the head angle, and (3) the combination of a body direction of more than 30 degrees and the arm pattern may be applicable for determining the presenter's interaction with the projection screen. [ABSTRACT FROM AUTHOR]

We present a fully automatic system for extracting the semantic structure of a typical academic presentation video, which captures the whole presentation stage with abundant camera motions such as panning, tilting, and zooming. Our system automatically detects and tracks both the projection screen and the presenter whenever they are visible in the video. By analyzing the image content of the tracked screen region, our system is able to detect slide progressions and extract a high-quality, non-occluded, geometrically-compensated image for each slide, resulting in a list of representative images that reconstruct the main presentation structure. Afterwards, our system recognizes text content and extracts keywords from the slides, which can be used for keyword-based video retrieval and browsing. Experimental results show that our system is able to generate more stable and accurate screen localization results than commonly-used object tracking methods. Our system also extracts more accurate presentation structures than general video summarization methods, for this specific type of video. [ABSTRACT FROM PUBLISHER]

This work presents the implementation of a 3D reconstruction system capable of reconstructing a 360-degree scene with a single acquisition using a projection of patterns. The system is formed by two modules: the first module is a CCD camera with a parabolic mirror that allows the acquisition of catadioptric images. The second module consists of a light projector and a parabolic mirror that is used to generate the pattern projections over the object that will be reconstructed. The projection system has a 360-degree field of view and both modules were calibrated to obtain the extrinsic parameters. To validate the functionality of the system, we performed 3D reconstructions of three objects, and show the reconstruction error analysis. [ABSTRACT FROM AUTHOR]

To implement a cloud game service platform supporting multiple users and devices based on real-time streaming, there are many technical needs, including game screen and sound capturing, audio/video encoding in real time created by a high-performance server-generated game screen, and real-time streaming to client devices, such as low-cost PCs, smart devices, and set-top boxes. We therefore present a game service platform for the running and management of the game screen, as well as running the sound on the server, in which the captured and encoded game screen and sound separately provide client devices through real-time streaming. The proposed platform offers Web-based services that allow game play on smaller end devices without requiring the games to be installed locally. [ABSTRACT FROM AUTHOR]