WorldWideScience

Sample records for controls visual coding

  1. Neural substrates of visual spatial coding and visual feedback control for hand movements in allocentric and target-directed tasks

    Directory of Open Access Journals (Sweden)

    Lore eThaler

    2011-08-01

    Full Text Available Neuropsychological evidence suggests that different brain areas may be involved in movements that are directed at visual targets (e.g. pointing or reaching, and movements that are based on allocentric visual information (e.g. drawing or copying. Here we used fMRI to investigate the neural correlates of these two types of movements in healthy volunteers. Subjects (n=14 performed right-hand movements in either a target-directed task (moving a cursor to a target dot or an allocentric task (moving a cursor to reproduce the distance and direction between two distal target dots with or without visual feedback about their hand movement. Movements were monitored with an MR compatible touch panel. A whole-brain analysis revealed that movements in allocentric conditions led to an increase in activity in the fundus of the left intraparietal sulcus (IPS, in posterior IPS, in bilateral dorsal premotor cortex (PMd, and in the Lateral Occipital Complex (LOC. Visual feedback in both target-directed and allocentric conditions led to an increase in activity in area MT+, superior parietal occipital cortex (SPOC and posterior IPS (all bilateral. In addition, we found that visual feedback affected brain activity differently in target-directed as compared to allocentric conditions, in particular in pre-supplementary motor area, PMd, IPS and parieto-occipital cortex. Our results, in combination with previous findings, suggest that the LOC is essential for allocentric visual coding and that SPOC is involved in visual feedback control. The differences in brain activity between target-directed and allocentric visual feedback conditions may be related to behavioral differences in visual feedback control. Our results advance the understanding of the visual coordinate frame used by the LOC. In addition, because of the nature of the allocentric task, our results have relevance for the understanding of neural substrates of magnitude estimation and vector-coding of movements.

  2. A Brain Computer Interface for Robust Wheelchair Control Application Based on Pseudorandom Code Modulated Visual Evoked Potential

    DEFF Research Database (Denmark)

    Mohebbi, Ali; Engelsholm, Signe K.D.; Puthusserypady, Sadasivan

    2015-01-01

    In this pilot study, a novel and minimalistic Brain Computer Interface (BCI) based wheelchair control application was developed. The system was based on pseudorandom code modulated Visual Evoked Potentials (c-VEPs). The visual stimuli in the scheme were generated based on the Gold code...

  3. Code Flows : Visualizing Structural Evolution of Source Code

    NARCIS (Netherlands)

    Telea, Alexandru; Auber, David

    2008-01-01

    Understanding detailed changes done to source code is of great importance in software maintenance. We present Code Flows, a method to visualize the evolution of source code geared to the understanding of fine and mid-level scale changes across several file versions. We enhance an existing visual met

  4. Code flows : Visualizing structural evolution of source code

    NARCIS (Netherlands)

    Telea, Alexandru; Auber, David

    2008-01-01

    Understanding detailed changes done to source code is of great importance in software maintenance. We present Code Flows, a method to visualize the evolution of source code geared to the understanding of fine and mid-level scale changes across several file versions. We enhance an existing visual met

  5. Informal Control code logic

    CERN Document Server

    Bergstra, Jan A

    2010-01-01

    General definitions as well as rules of reasoning regarding control code production, distribution, deployment, and usage are described. The role of testing, trust, confidence and risk analysis is considered. A rationale for control code testing is sought and found for the case of safety critical embedded control code.

  6. Visual mismatch negativity: A predictive coding view

    Directory of Open Access Journals (Sweden)

    Gabor eStefanics

    2014-09-01

    Full Text Available An increasing number of studies investigate the visual mismatch negativity (vMMN or use the vMMN as a tool to probe various aspects of human cognition. This paper reviews the theoretical underpinnings of vMMN in the light of methodological considerations and provides recommendations for measuring and interpreting the vMMN. The following key issues are discussed from the experimentalist’s point of view in a predictive coding framework: 1 experimental protocols and procedures to control ‘refractoriness’ effects; 2 methods to control attention; 3 vMMN and veridical perception.

  7. A Line Based Visualization of Code Evolution

    NARCIS (Netherlands)

    Voinea, S.L.; Telea, A.; Wijk, J.J. van

    2005-01-01

    The source code of software systems changes many times during the system lifecycle. We study how developers can get insight in these changes in order to understand the project context and the product artifacts. For this we propose new techniques for code evolution representation and visualization in

  8. Version-Centric Visualization of Code Evolution

    NARCIS (Netherlands)

    Voinea, S.L.; Telea, A.; Chaudron, M.

    2005-01-01

    The source code of software systems changes many times during the system lifecycle. We study how developers can get insight in these changes in order to understand the project context and the product artifacts. For this we propose new techniques for code evolution representation and visualization in

  9. Spatial Coding of Individuals with Visual Impairments

    Science.gov (United States)

    Papadopoulos, Konstantinos; Koustriava, Eleni; Kartasidou, Lefkothea

    2012-01-01

    The aim of this study is to examine the ability of children and adolescents with visual impairments to code and represent near space. Moreover, it examines the impact of the strategies they use and individual differences in their performance. A total of 30 individuals with visual impairments up to the age of 18 were given eight different object…

  10. CVSscan : Visualization of Code Evolution

    NARCIS (Netherlands)

    Voinea, Lucian; Telea, Alex; Wijk, Jarke J. van

    2005-01-01

    During the life cycle of a software system, the source code is changed many times. We study how developers can be enabled to get insight in these changes, in order to understand the status, history and structure better, as well as for instance the roles played by various contributors. We present CVS

  11. Development of Visual CINDER Code with Visual C⧣.NET

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Oyeon [Institute for Modeling and Simulation Convergence, Daegu (Korea, Republic of)

    2016-10-15

    CINDER code, CINDER' 90 or CINDER2008 that is integrated with the Monte Carlo code, MCNPX, is widely used to calculate the inventory of nuclides in irradiated materials. The MCNPX code provides decay processes to the particle transport scheme that traditionally only covered prompt processes. The integration schemes serve not only the reactor community (MCNPX burnup) but also the accelerator community as well (residual production information). The big benefit for providing these options lies in the easy cross comparison of the transmutation codes since the calculations are based on exactly the same material, neutron flux and isotope production/destruction inputs. However, it is just frustratingly cumbersome to use. In addition, multiple human interventions may increase the possibility of making errors. The number of significant digits in the input data varies in steps, which may cause big errors for highly nonlinear problems. Thus, it is worthwhile to find a new way to wrap all the codes and procedures in one consistent package which can provide ease of use. The visual CINDER code development is underway with visual C .NET framework. It provides a few benefits for the atomic transmutation simulation with CINDER code. A few interesting and useful properties of visual C .NET framework are introduced. We also showed that the wrapper could make the simulation accurate for highly nonlinear transmutation problems and also increase the possibility of direct combination a radiation transport code MCNPX with CINDER code. Direct combination of CINDER with MCNPX in a wrapper will provide more functionalities for the radiation shielding and prevention study.

  12. Interactive Visual Mechanisms for Exploring Source Code Evolution

    NARCIS (Netherlands)

    Telea, Alexandru; Voinea, Lucian

    2005-01-01

    The Visual Code Navigator (VCN) is an ongoing effort to build a visual environment for interactive visualization of large source code bases. We present two techniques that extend the previous work done on the VCN. We propose an efficient and effective mechanism for specifying and visualizing queries

  13. The Visual Code Navigator : An Interactive Toolset for Source Code Investigation

    NARCIS (Netherlands)

    Lommerse, Gerard; Nossin, Freek; Voinea, Lucian; Telea, Alexandru

    2005-01-01

    We present the Visual Code Navigator, a set of three interrelated visual tools that we developed for exploring large source code software projects from three different perspectives, or views: The syntactic view shows the syntactic constructs in the source code. The symbol view shows the objects a fi

  14. The Visual Code Navigator : An Interactive Toolset for Source Code Investigation

    NARCIS (Netherlands)

    Lommerse, Gerard; Nossin, Freek; Voinea, Lucian; Telea, Alexandru

    2005-01-01

    We present the Visual Code Navigator, a set of three interrelated visual tools that we developed for exploring large source code software projects from three different perspectives, or views: The syntactic view shows the syntactic constructs in the source code. The symbol view shows the objects a

  15. JPEG2000 COMPRESSION CODING USING HUMAN VISUAL SYSTEM MODEL

    Institute of Scientific and Technical Information of China (English)

    Xiao Jiang; Wu Chengke

    2005-01-01

    In order to apply the Human Visual System (HVS) model to JPEG2000 standard,several implementation alternatives are discussed and a new scheme of visual optimization isintroduced with modifying the slope of rate-distortion. The novelty is that the method of visual weighting is not lifting the coefficients in wavelet domain, but is complemented by code stream organization. It remains all the features of Embedded Block Coding with Optimized Truncation (EBCOT) such as resolution progressive, good robust for error bit spread and compatibility of lossless compression. Well performed than other methods, it keeps the shortest standard codestream and decompression time and owns the ability of VIsual Progressive (VIP) coding.

  16. code_swarm: a design study in organic software visualization.

    Science.gov (United States)

    Ogawa, Michael; Ma, Kwan-Liu

    2009-01-01

    In May of 2008, we published online a series of software visualization videos using a method called code_swarm. Shortly thereafter, we made the code open source and its popularity took off. This paper is a study of our code swarm application, comprising its design, results and public response. We share our design methodology, including why we chose the organic information visualization technique, how we designed for both developers and a casual audience, and what lessons we learned from our experiment. We validate the results produced by code_swarm through a qualitative analysis and by gathering online user comments. Furthermore, we successfully released the code as open source, and the software community used it to visualize their own projects and shared their results as well. In the end, we believe code_swarm has positive implications for the future of organic information design and open source information visualization practice.

  17. Development of Visualization Software for McCARD Code

    Science.gov (United States)

    Park, Chang Je; Lee, Byungchul; Shim, Hyung Jin; Yoeng Choi, Kwang; Roh, Chang Hyun

    2014-06-01

    In order to confirm geometrical modeling of input file of the McCARD (Monte Carlo Code for Advanced Reactor Design and analysis) code, a 2D visualization program with a 3D modeling has been developed. It requires lots of mathematical operations and advanced technologies for design graphical program of complicated geometries. The software is coded with the visual C++ language and run under the Windows PC environment.

  18. Predictive coding for motion stimuli in human early visual cortex

    NARCIS (Netherlands)

    Schellekens, Wouter; van Wezel, Richard J A; Petridou, Natalia; Ramsey, Nick F.; Raemaekers, Mathijs

    2016-01-01

    The current study investigates if early visual cortical areas, V1, V2 and V3, use predictive coding to process motion information. Previous studies have reported biased visual motion responses at locations where novel visual information was presented (i.e., the motion trailing edge), which is plausi

  19. Predictive coding for motion stimuli in human early visual cortex

    NARCIS (Netherlands)

    Schellekens, Wouter; Wezel, van Richard J.A.; Petridou, Natalia; Ramsey, Nick F.; Raemeakers, Mathijs; Zaborszky, L.; Zilles, K.

    2014-01-01

    The current study investigates if early visual cortical areas, V1, V2 and V3, use predictive coding to process motion information. Previous studies have reported biased visual motion responses at locations where novel visual information was presented (i.e., the motion trailing edge), which is plausi

  20. A line-based visualization of code evolution

    OpenAIRE

    Voinea, SL Lucian; Telea, AC Alexandru; Wijk, van, M.N.

    2005-01-01

    The source code of software systems changes many times during the system lifecycle. We study how developers can get insight in these changes in order to understand the project context and the product artifacts. For this we propose new techniques for code evolution representation and visualization interaction from a version-centric perspective. Central to our approach is a line-based display of the changing code, where each file version is shown as a column and the horizontal axis shows time. ...

  1. 06301 Working Session Summary: Presentation and Visualization of Redundant Code

    OpenAIRE

    Walenstein, Andrew; Cordy, James R.; Evans, William S.; Hassan, Ahmed; Kamiya, Toshihiro; Kapser, Cory; Merlo, Ettore

    2007-01-01

    This report summarizes the proceedings of a workshop discussion session presentation and visualization of aspects relating to duplicated, copied, or cloned code. The main outcomes of the working session were: (a) a realization that two researchers had independently generated very similar methods for browsing and visualization clone "clusters," and (b) a list of questions for visualization, particularly in relation to how the "proximity" of clones may relate to interest in t...

  2. Visual Coding of Human Bodies: Perceptual Aftereffects Reveal Norm-Based, Opponent Coding of Body Identity

    Science.gov (United States)

    Rhodes, Gillian; Jeffery, Linda; Boeing, Alexandra; Calder, Andrew J.

    2013-01-01

    Despite the discovery of body-selective neural areas in occipitotemporal cortex, little is known about how bodies are visually coded. We used perceptual adaptation to determine how body identity is coded. Brief exposure to a body (e.g., anti-Rose) biased perception toward an identity with opposite properties (Rose). Moreover, the size of this…

  3. Intuitive Source Code Visualization Tools for Improving Student Comprehension: BRICS

    CERN Document Server

    Pearson, Christopher; Coady, Yvonne

    2008-01-01

    Even relatively simple code analysis can be a daunting task for many first year students. Perceived complexity, coupled with foreign and harsh syntax, often outstrips the ability for students to take in what they are seeing in terms of their verbal memory. That is, first year students often lack the experience to encode critical building blocks in source code, and their interrelationships, into their own words. We believe this argues for the need for IDEs to provide additional support for representations that would appeal directly to visual memory. In this paper, we examine this need for intuitive source code visualization tools that are easily accessible to novice programmers, discuss the requirements for such a tool, and suggest a novel idea that takes advantage of human peripheral vision to achieve stronger overall code structure awareness.

  4. Machine structure oriented control code logic

    NARCIS (Netherlands)

    Bergstra, J.A.; Middelburg, C.A.

    2009-01-01

    Control code is a concept that is closely related to a frequently occurring practitioner’s view on what is a program: code that is capable of controlling the behaviour of some machine. We present a logical approach to explain issues concerning control codes that are independent of the details of the

  5. Distributed Estimation, Coding, and Scheduling in Wireless Visual Sensor Networks

    Science.gov (United States)

    Yu, Chao

    2013-01-01

    In this thesis, we consider estimation, coding, and sensor scheduling for energy efficient operation of wireless visual sensor networks (VSN), which consist of battery-powered wireless sensors with sensing (imaging), computation, and communication capabilities. The competing requirements for applications of these wireless sensor networks (WSN)…

  6. Distributed Estimation, Coding, and Scheduling in Wireless Visual Sensor Networks

    Science.gov (United States)

    Yu, Chao

    2013-01-01

    In this thesis, we consider estimation, coding, and sensor scheduling for energy efficient operation of wireless visual sensor networks (VSN), which consist of battery-powered wireless sensors with sensing (imaging), computation, and communication capabilities. The competing requirements for applications of these wireless sensor networks (WSN)…

  7. 3D visualization for the MARS14 Code

    Energy Technology Data Exchange (ETDEWEB)

    Rzepecki, Jaroslaw P.; Kostin, Mikhail A; Mokhov, Nikolai V.

    2003-01-23

    A new three-dimensional visualization engine has been developed for the MARS14 code system. It is based on the OPENINVENTOR graphics library and integrated with the MARS built-in two-dimensional Graphical-User Interface, MARS-GUI-SLICE. The integrated package allows thorough checking of complex geometry systems and their fragments, materials, magnetic fields, particle tracks along with a visualization of calculated 2-D histograms. The algorithms and their optimization are described for two geometry classes along with examples in accelerator and detector applications.

  8. Modern Method for Detecting Web Phishing Using Visual Cryptography (VC and Quick Response Code (QR code

    Directory of Open Access Journals (Sweden)

    Ms. Ashvini Kute

    2015-01-01

    Full Text Available Phishing is an attempt by an individual or a group to thieve personal confidential information such as passwords, credit card information etc from unsuspecting victims for identity theft, financial gain and other fraudulent activities. Here an image based (QR codes authentication using Visual Cryptography (VC is used. The use of Visual cryptography is explored to convert the QR code into two shares and both these shares can then be transmitted separately. One Time Passwords (OTP is passwords which are valid only for a session to validate the user within a specified amount of time. In this paper we are presenting a new authentication scheme for secure OTP distribution in phishing website detection through VC and QR codes.

  9. Modern Method for Detecting Web Phishing Using Visual Cryptography (VC and Quick Response Code (QR code

    Directory of Open Access Journals (Sweden)

    Ms. Ashvini Kute

    2015-05-01

    Full Text Available Phishing is an attempt by an individual or a group to thieve personal confidential information such as passwords, credit card information etc from unsuspecting victims for identity theft, financial gain and other fraudulent activities. Here an image based (QR codes authentication using Visual Cryptography (VC is used. The use of Visual cryptography is explored to convert the QR code into two shares and both these shares can then be transmitted separately. One Time Passwords (OTP is passwords which are valid only for a session to validate the user within a specified amount of time. In this paper we are presenting a new authentication scheme for secure OTP distribution in phishing website detection through VC and QR codes.

  10. Inter-subject neural code converter for visual image representation.

    Science.gov (United States)

    Yamada, Kentaro; Miyawaki, Yoichi; Kamitani, Yukiyasu

    2015-06-01

    Brain activity patterns differ from person to person, even for an identical stimulus. In functional brain mapping studies, it is important to align brain activity patterns between subjects for group statistical analyses. While anatomical templates are widely used for inter-subject alignment in functional magnetic resonance imaging (fMRI) studies, they are not sufficient to identify the mapping between voxel-level functional responses representing specific mental contents. Recent work has suggested that statistical learning methods could be used to transform individual brain activity patterns into a common space while preserving representational contents. Here, we propose a flexible method for functional alignment, "neural code converter," which converts one subject's brain activity pattern into another's representing the same content. The neural code converter was designed to learn statistical relationships between fMRI activity patterns of paired subjects obtained while they saw an identical series of stimuli. It predicts the signal intensity of individual voxels of one subject from a pattern of multiple voxels of the other subject. To test this method, we used fMRI activity patterns measured while subjects observed visual images consisting of random and structured patches. We show that fMRI activity patterns for visual images not used for training the converter could be predicted from those of another subject where brain activity was recorded for the same stimuli. This confirms that visual images can be accurately reconstructed from the predicted activity patterns alone. Furthermore, we show that a classifier trained only on predicted fMRI activity patterns could accurately classify measured fMRI activity patterns. These results demonstrate that the neural code converter can translate neural codes between subjects while preserving contents related to visual images. While this method is useful for functional alignment and decoding, it may also provide a basis for

  11. A geometric view on early and middle level visual coding.

    Science.gov (United States)

    Barth, E

    2000-01-01

    As opposed to dealing with the geometry of objects in the 3D world, this paper considers the geometry of the visual input itself, i.e. the geometry of the spatio-temporal hypersurface defined by image intensity as a function of two spatial coordinates and time. The results show how the Riemann curvature tensor of this hypersurface represents speed and direction of motion, and thereby allows to predict global motion percepts and properties of MT neurons. It is argued that important aspects of early and middle level visual coding may be understood as resulting from basic geometric processing of the spatio-temporal visual input. Finally, applications show that the approach can improve the computation of motion.

  12. Tetrahedral gray code for visualization of genome information.

    Science.gov (United States)

    Ichinose, Natsuhiro; Yada, Tetsushi; Gotoh, Osamu

    2014-01-01

    We propose a tetrahedral Gray code that facilitates visualization of genome information on the surfaces of a tetrahedron, where the relative abundance of each [Formula: see text]-mer in the genomic sequence is represented by a color of the corresponding cell of a triangular lattice. For biological significance, the code is designed such that the [Formula: see text]-mers corresponding to any adjacent pair of cells differ from each other by only one nucleotide. We present a simple procedure to draw such a pattern on the development surfaces of a tetrahedron. The thus constructed tetrahedral Gray code can demonstrate evolutionary conservation and variation of the genome information of many organisms at a glance. We also apply the tetrahedral Gray code to the honey bee (Apis mellifera) genome to analyze its methylation structure. The results indicate that the honey bee genome exhibits CpG overrepresentation in spite of its methylation ability and that two conserved motifs, CTCGAG and CGCGCG, in the unmethylated regions are responsible for the overrepresentation of CpG.

  13. Tetrahedral gray code for visualization of genome information.

    Directory of Open Access Journals (Sweden)

    Natsuhiro Ichinose

    Full Text Available We propose a tetrahedral Gray code that facilitates visualization of genome information on the surfaces of a tetrahedron, where the relative abundance of each [Formula: see text]-mer in the genomic sequence is represented by a color of the corresponding cell of a triangular lattice. For biological significance, the code is designed such that the [Formula: see text]-mers corresponding to any adjacent pair of cells differ from each other by only one nucleotide. We present a simple procedure to draw such a pattern on the development surfaces of a tetrahedron. The thus constructed tetrahedral Gray code can demonstrate evolutionary conservation and variation of the genome information of many organisms at a glance. We also apply the tetrahedral Gray code to the honey bee (Apis mellifera genome to analyze its methylation structure. The results indicate that the honey bee genome exhibits CpG overrepresentation in spite of its methylation ability and that two conserved motifs, CTCGAG and CGCGCG, in the unmethylated regions are responsible for the overrepresentation of CpG.

  14. Synchronization trigger control system for flow visualization

    Science.gov (United States)

    Chun, K. S.

    1987-01-01

    The use of cinematography or holographic interferometry for dynamic flow visualization in an internal combustion engine requires a control device that globally synchronizes camera and light source timing at a predefined shaft encoder angle. The device is capable of 0.35 deg resolution for rotational speeds of up to 73 240 rpm. This was achieved by implementing the shaft encoder signal addressed look-up table (LUT) and appropriate latches. The developed digital signal processing technique achieves 25 nsec of high speed triggering angle detection by using direct parallel bit comparison of the shaft encoder digital code with a simulated angle reference code, instead of using angle value comparison which involves more complicated computation steps. In order to establish synchronization to an AC reference signal whose magnitude is variant with the rotating speed, a dynamic peak followup synchronization technique has been devised. This method scrutinizes the reference signal and provides the right timing within 40 nsec. Two application examples are described.

  15. Consensus Coding as a Tool in Visual Appearance Research

    Directory of Open Access Journals (Sweden)

    D R Simmons

    2011-04-01

    Full Text Available A common problem in visual appearance research is how to quantitatively characterise the visual appearance of a region of an image which is categorised by human observers in the same way. An example of this is scarring in medical images (Ayoub et al, 2010, The Cleft-Palate Craniofacial Journal, in press. We have argued that “scarriness” is itself a visual appearance descriptor which summarises the distinctive combination of colour, texture and shape information which allows us to distinguish scarred from non-scarred tissue (Simmons et al, ECVP 2009. Other potential descriptors for other image classes would be “metallic”, “natural”, or “liquid”. Having developed an automatic algorithm to locate scars in medical images, we then tested “ground truth” by asking untrained observers to draw around the region of scarring. The shape and size of the scar on the image was defined by building a contour plot of the agreement between observers' outlines and thresholding at the point above which 50% of the observers agreed: a consensus coding scheme. Based on the variability in the amount of overlap between the scar as defined by the algorithm, and the consensus scar of the observers, we have concluded that the algorithm does not completely capture the putative appearance descriptor “scarriness”. A simultaneous analysis of qualitative descriptions of the scarring by the observers revealed that other image features than those encoded by the algorithm (colour and texture might be important, such as scar boundary shape. This approach to visual appearance research in medical imaging has potential applications in other application areas, such as botany, geology and archaeology.

  16. Visualized kinematics code for two-body nuclear reactions

    Science.gov (United States)

    Lee, E. J.; Chae, K. Y.

    2016-05-01

    The one or few nucleon transfer reaction has been a great tool for investigating the single-particle properties of a nucleus. Both stable and exotic beams are utilized to study transfer reactions in normal and inverse kinematics, respectively. Because many energy levels of the heavy recoil from the two-body nuclear reaction can be populated by using a single beam energy, identifying each populated state, which is not often trivial owing to high level-density of the nucleus, is essential. For identification of the energy levels, a visualized kinematics code called VISKIN has been developed by utilizing the Java programming language. The development procedure, usage, and application of the VISKIN is reported.

  17. A fast block mode selection approach for H. Visual coding

    Institute of Scientific and Technical Information of China (English)

    LIN Wei-yao; Fang Xiang-zhong; HUANG Xiu-chao; LI Dian; LIU Xiao-feng

    2006-01-01

    In this paper,a new fast mode-selection approach is proposed.This algorithm combines the proposed approaches of mode pre-decision and precise large-small mode decision,by selecting the best mode efficiently.Experimental results show that the proposed approach can reduce the computational cost of full search and fast multi-block motion estimation by 8% and 45%,respectively,with similar visual quality and bit rate.The proposed algorithm also reduces by 75% the computational cost of the large-small mode isolation algorithm for low-motion sequence coding,and with 0.06 PSNR gain and 3.7% reduction in bit rate.

  18. Code Pulse: Software Assurance (SWA) Visual Analytics for Dynamic Analysis of Code

    Science.gov (United States)

    2014-09-01

    ZAP ) DAST tool to measure its testing coverage, and several test...source world, OWASP ZAP . Distinctive within the penetration testing tool space however is the scarci- ty of visualization tools, particularly as they...Transmission Control Protocol UI User Interface ZAP Zed Attack Proxy Approved for Public Release; Distribution Unlimited. 37

  19. Verbal to visual code switching improves working memory in older adults: An fMRI study

    Directory of Open Access Journals (Sweden)

    Mariko eOsaka

    2012-02-01

    Full Text Available The effects of verbal to visual code switching training on working memory performance were investigated in the elderly. Twenty-five elderly people were introduced to a verbal to visual code switching strategy (training group while the other 25 were not (control group. During this strategy training period, participants in the training group practiced focusing their attention on a target word both by drawing the target’s figure and by forming mental images of the target. To explore the neural substrates underlying strategy effects, fMRI was used to measure brain activity of the elderly in both groups while they performed a working memory task (reading span test, RST, before and after the attention training period. RST recognition accuracy was enhanced only in the training group. fMRI data for this group showed increased activation in the anterior cingulate cortex (ACC, a region that typically shows activation in young adults performing the RST. Furthermore, activation was found both in the left and right inferior parietal lobule (IPL and right superior parietal lobule (SPL, while there was no activation in these areas for the control group. These findings suggest that using a strategy of verbal to visual code switching helped the elderly participants to maintain the words in working memory.

  20. Quantum Codes for Controlling Coherent Evolution

    CERN Document Server

    Sharf, Y; Cory, D G; Sharf, Yehuda; Havel, Timothy F.; Cory, David G.

    2000-01-01

    Control over spin dynamics has been obtained in NMR via coherent averaging, which is implemented through a sequence of RF pulses, and via quantum codes which can protect against incoherent evolution. Here, we discuss the design and implementation of quantum codes to protect against coherent evolution. A detailed example is given of a quantum code for protecting two data qubits from evolution under a weak coupling (Ising) term in the Hamiltonian, using an ``isolated'' ancilla which does not evolve on the experimental time scale. The code is realized in a three-spin system by liquid-state NMR spectroscopy on 13C-labelled alanine, and tested for two initial states. It is also shown that for coherent evolution and isolated ancillae, codes exist that do not require the ancillae to initially be in a (pseudo-)pure state. Finally, it is shown that even with non-isolated ancillae quantum codes exist which can protect against evolution under weak coupling. An example is presented for a six qubit code that protects two ...

  1. Error Correcting Codes for Distributed Control

    CERN Document Server

    Sukhavasi, Ravi Teja

    2011-01-01

    The problem of stabilizing an unstable plant over a noisy communication link is an increasingly important one that arises in applications of networked control systems. Although the work of Schulman and Sahai over the past two decades, and their development of the notions of "tree codes"\\phantom{} and "anytime capacity", provides the theoretical framework for studying such problems, there has been scant practical progress in this area because explicit constructions of tree codes with efficient encoding and decoding did not exist. To stabilize an unstable plant driven by bounded noise over a noisy channel one needs real-time encoding and real-time decoding and a reliability which increases exponentially with decoding delay, which is what tree codes guarantee. We prove that linear tree codes occur with high probability and, for erasure channels, give an explicit construction with an expected decoding complexity that is constant per time instant. We give novel sufficient conditions on the rate and reliability req...

  2. Movement and visual coding: the structure of visuo-spatial working memory.

    Science.gov (United States)

    Quinn, J G

    2008-03-01

    The influential model of verbal working memory (WM) introduced by Baddeley and Hitch (Recent advances in learning and motivation. Academic, New York, 1974) comprised three interacting component parts; an executive controller and two subservient systems. The two subservient systems, one underpinning verbal processing and the other underpinning visual processing are themselves subdivided. In the verbal system, a passive phonological store is maintained by an active phonological loop, which is able to rehearse the material in the passive store. The visual working memory system has traditionally been thought of as having a similar architecture with a passive visual store being maintained by an active store, which codes in terms of movement over space. The paper discusses the evidence for this relationship in visuo-spatial WM and concludes that the architecture does not fit well with the experimental literature. A direction for future research is suggested.

  3. Influence of hemianopic visual field loss on visual motor control.

    Directory of Open Access Journals (Sweden)

    Diederick C Niehorster

    Full Text Available BACKGROUND: Homonymous hemianopia (HH is an anisotropic visual impairment characterized by the binocular inability to see one side of the visual field. Patients with HH often misperceive visual space. Here we investigated how HH affects visual motor control. METHODS AND FINDINGS: Seven patients with complete HH and no neglect or cognitive decline and seven gender- and age-matched controls viewed displays in which a target moved randomly along the horizontal or the vertical axis. They used a joystick to control the target movement to keep it at the center of the screen. We found that the mean deviation of the target position from the center of the screen along the horizontal axis was biased toward the blind side for five out of seven HH patients. More importantly, while the normal vision controls showed more precise control and larger response amplitudes when the target moved along the horizontal rather than the vertical axis, the control performance of the HH patients was not different between these two target motion experimental conditions. CONCLUSIONS: Compared with normal vision controls, HH affected patients' control performance when the target moved horizontally (i.e., along the axis of their visual impairment rather than vertically. We conclude that hemianopia affects the use of visual information for online control of a moving target specific to the axis of visual impairment. The implications of the findings for driving in hemianopic patients are discussed.

  4. Extending the entry consistency model to enable efficient visualization for code-coupling grid applications

    OpenAIRE

    Antoniu, Gabriel; Cudennec, Loïc; Monnet, Sébastien

    2006-01-01

    This paper addresses the problem of efficient visualization of shared data within code coupling grid applications. These applications are structured as a set of distributed, autonomous, weakly-coupled codes. We focus on the case where the codes are able to interact using the abstraction of a shared data space. We propose an efficient visualization scheme by adapting the mechanisms used to maintain the data consistency. We introduce a new operation called relaxed read, as an extension to the e...

  5. Visual control of walking velocity.

    Science.gov (United States)

    François, Matthieu; Morice, Antoine H P; Bootsma, Reinoud J; Montagne, Gilles

    2011-06-01

    Even if optical correlates of self-motion velocity have already been identified, their contribution to the control of displacement velocity remains to be established. In this study, we used a virtual reality set-up coupled to a treadmill to test the role of both Global Optic Flow Rate (GOFR) and Edge Rate (ER) in the regulation of walking velocity. Participants were required to walk at a constant velocity, corresponding to their preferred walking velocity, while eye height and texture density were manipulated. This manipulation perturbed the natural relationship between the actual walking velocity and its optical specification by GOFR and ER, respectively. Results revealed that both these sources of information are indeed used by participants to control walking speed, as demonstrated by a slowing down of actual walking velocity when the optical specification of velocity by either GOFR or ER gives rise to an overestimation of actual velocity, and vice versa. Gait analyses showed that these walking velocity adjustments result from simultaneous adaptations in both step length and step duration. The role of visual information in the control of self-motion velocity is discussed in relation with other factors.

  6. Technique for using a geometry and visualization system to monitor and manipulate information in other codes

    Science.gov (United States)

    Dickens, Thomas P.

    1992-01-01

    A technique was developed to allow the Aero Grid and Paneling System (AGPS), a geometry and visualization system, to be used as a dynamic real-time geometry monitor, manipulator, and interrogator for other codes. This technique involves the direct connection of AGPS with one or more external codes through the use of Unix pipes. AGPS has several commands that control communication with the external program. The external program uses several special subroutines that allow simple, direct communication with AGPS. The external program creates AGPS command lines and transmits the line over the pipes or communicates on a subroutine level. AGPS executes the commands, displays graphics/geometry information, and transmits the required solutions back to the external program. The basic ideas discussed in this paper could easily be implemented in other graphics/geometry systems currently in use or under development.

  7. Trellis and turbo coding iterative and graph-based error control coding

    CERN Document Server

    Schlegel, Christian B

    2015-01-01

    This new edition has been extensively revised to reflect the progress in error control coding over the past few years. Over 60% of the material has been completely reworked, and 30% of the material is original. Convolutional, turbo, and low density parity-check (LDPC) coding and polar codes in a unified framework. Advanced research-related developments such as spatial coupling. A focus on algorithmic and implementation aspects of error control coding.

  8. Structural Analysis and Visualization of C++ Code Evolution using Syntax Trees

    NARCIS (Netherlands)

    Chevalier, Fanny; Auber, David; Telea, Alexandru

    2007-01-01

    We present a method to detect and visualize evolution patterns in C++ source code. Our method consists of three steps. First, we extract an annotated syntax tree (AST) from each version of a given C++ source code. Next, we hash the extracted syntax nodes based on a metric combining structure and typ

  9. Holland Vocational Personality Codes and People with Visual Disabilities: A Need for Caution.

    Science.gov (United States)

    Jones, W. Paul

    1995-01-01

    This study compared scores of adults (n=34) with blindness and sighted individuals on the Holland Vocational Preference Inventory (VPI) and the Myers-Briggs Type Indicator (MBTI). Findings indicated a higher incidence of unusual vocational codes selected by people with visual disabilities on the VPI and few differences between visually impaired…

  10. Frequency spectrum might act as communication code between retina and visual cortex I

    Directory of Open Access Journals (Sweden)

    Xu Yang

    2015-12-01

    Full Text Available AIM: To explore changes and possible communication relationship of local potential signals recorded simultaneously from retina and visual cortex I (V1. METHODS: Fourteen C57BL/6J mice were measured with pattern electroretinogram (PERG and pattern visually evoked potential (PVEP and fast Fourier transform has been used to analyze the frequency components of those signals. RESULTS: The amplitude of PERG and PVEP was measured at about 36.7 µV and 112.5 µV respectively and the dominant frequency of PERG and PVEP, however, stay unchanged and both signals do not have second, or otherwise, harmonic generation. CONCLUSION: The results suggested that retina encodes visual information in the way of frequency spectrum and then transfers it to primary visual cortex. The primary visual cortex accepts and deciphers the input visual information coded from retina. Frequency spectrum may act as communication code between retina and V1.

  11. Structural Analysis and Visualization of C++ Code Evolution using Syntax Trees

    OpenAIRE

    Chevalier, Fanny; Auber, David; Telea, Alexandru

    2007-01-01

    International audience; We present a method to detect and visualize evolution patterns in C++ source code. Our method consists of three steps. First, we extract an annotated syntax tree (AST) from each version of a given C++ source code. Next, we hash the extracted syntax nodes based on a metric combining structure and type information, and construct matches (correspondences) between similar-hash subtrees. Our technique detects code fragments which have not changed, or changed little, during ...

  12. Motor Training: Comparison of Visual and Auditory Coded Proprioceptive Cues

    Directory of Open Access Journals (Sweden)

    Philip Jepson

    2012-05-01

    Full Text Available Self-perception of body posture and movement is achieved through multi-sensory integration, particularly the utilisation of vision, and proprioceptive information derived from muscles and joints. Disruption to these processes can occur following a neurological accident, such as stroke, leading to sensory and physical impairment. Rehabilitation can be helped through use of augmented visual and auditory biofeedback to stimulate neuro-plasticity, but the effective design and application of feedback, particularly in the auditory domain, is non-trivial. Simple auditory feedback was tested by comparing the stepping accuracy of normal subjects when given a visual spatial target (step length and an auditory temporal target (step duration. A baseline measurement of step length and duration was taken using optical motion capture. Subjects (n=20 took 20 ‘training’ steps (baseline ±25% using either an auditory target (950 Hz tone, bell-shaped gain envelope or visual target (spot marked on the floor and were then asked to replicate the target step (length or duration corresponding to training with all feedback removed. Visual cues (mean percentage error=11.5%; SD ± 7.0%; auditory cues (mean percentage error = 12.9%; SD ± 11.8%. Visual cues elicit a high degree of accuracy both in training and follow-up un-cued tasks; despite the novelty of the auditory cues present for subjects, the mean accuracy of subjects approached that for visual cues, and initial results suggest a limited amount of practice using auditory cues can improve performance.

  13. Coding and inferences from visual and other behavioural data

    DEFF Research Database (Denmark)

    Sønderstrup-Andersen, Hans Henrik Krogh; Andersen, Henning Boje; Hilburn, B.G.;

    In this report we focus on developing and testing methods for the analysis of team situation awareness. That is, focus is on methods for analysing team situation awareness relating visual and other behavioural data; development of tools to facilitate usability and efficiency of Eye Point of Gaze ...

  14. Training Visual Control in Wheelchair Basketball Shooting

    Science.gov (United States)

    Oudejans, Raoul R. D.; Heubers, Sjoerd; Ruitenbeek, Jean-Rene J. A. C.; Janssen, Thomas W. J.

    2012-01-01

    We examined the effects of visual control training on expert wheelchair basketball shooting, a skill more difficult than in regular basketball, as players shoot from a seated position to the same rim height. The training consisted of shooting with a visual constraint that forced participants to use target information as late as possible.…

  15. A morphology screen coding anti-counterfeiting method based on visual characteristics

    Institute of Scientific and Technical Information of China (English)

    ZHAO Li-long; GU Ze-cang; FANG Zhi-liang

    2008-01-01

    A paper information anti-fake and tamper-proofing method based on human visual characteristics and morphology screen coding technology is proposed. Through controlling the distribution of mathematical morphology of screen dot-matrix, warning mark and information are hidden in the background texture. Because of the differences between human vision and the duplicate characteristics of copy machine, warning mark which can not be discriminated by human eyes will emerge after copy. Tampered or fake certificates can be verified by comparing embedded information which is extracted from scanned image of certificate with plain text printed on the certificate. This method is applied in many bills and certificates. Experimental results show that the identification accuracy is above 98%

  16. Code Samples Used for Complexity and Control

    Science.gov (United States)

    Ivancevic, Vladimir G.; Reid, Darryn J.

    2015-11-01

    The following sections are included: * MathematicaⓇ Code * Generic Chaotic Simulator * Vector Differential Operators * NLS Explorer * 2C++ Code * C++ Lambda Functions for Real Calculus * Accelerometer Data Processor * Simple Predictor-Corrector Integrator * Solving the BVP with the Shooting Method * Linear Hyperbolic PDE Solver * Linear Elliptic PDE Solver * Method of Lines for a Set of the NLS Equations * C# Code * Iterative Equation Solver * Simulated Annealing: A Function Minimum * Simple Nonlinear Dynamics * Nonlinear Pendulum Simulator * Lagrangian Dynamics Simulator * Complex-Valued Crowd Attractor Dynamics * Freeform Fortran Code * Lorenz Attractor Simulator * Complex Lorenz Attractor * Simple SGE Soliton * Complex Signal Presentation * Gaussian Wave Packet * Hermitian Matrices * Euclidean L2-Norm * Vector/Matrix Operations * Plain C-Code: Levenberg-Marquardt Optimizer * Free Basic Code: 2D Crowd Dynamics with 3000 Agents

  17. Surround suppression and sparse coding in visual and barrel cortices

    Directory of Open Access Journals (Sweden)

    Robert N S Sachdev

    2012-07-01

    Full Text Available During natural vision the entire retina is stimulated. Likewise, during natural tactile behaviors, spatially extensive regions of the somatosensory surface are co-activated. The large spatial extent of naturalistic stimulation means that surround suppression, a phenomenon whose neural mechanisms remain a matter of debate, must arise during natural behavior. To identify common neural motifs that might instantiate surround suppression across modalities, we review models of surround suppression and compare the evidence supporting the competing ideas that surround suppression has either cortical or sub-cortical origins in visual and barrel cortex. In the visual system there is general agreement lateral inhibitory mechanisms contribute to surround suppression, but little direct experimental evidence that intracortical inhibition plays a major role. Two intracellular recording studies of V1, one using naturalistic stimuli (Haider et al., 2010, the other sinusoidal gratings (Ozeki et al., 2009, sought to identify the causes of reduced activity in V1 with increasing stimulus size, a hallmark of surround suppression. The former attributed this effect to increased inhibition, the latter to largely balanced withdrawal of excitation and inhibition. In rodent primary somatosensory barrel cortex, multi-whisker responses are generally weaker than single whisker responses, suggesting multi-whisker stimulation engages similar surround suppressive mechanisms. The origins of suppression in S1 remain elusive: studies have implicated brainstem lateral/internuclear interactions and both thalamic and cortical inhibition. Although the anatomical organization and instantiation of surround suppression in the visual and somatosensory systems differ, we consider the idea that one common function of surround suppression, in both modalities, is to remove the statistical redundancies associated with natural stimuli by increasing the sparseness or selectivity of sensory

  18. Acquired Codes of Meaning in Data Visualization and Infographics: Beyond Perceptual Primitives.

    Science.gov (United States)

    Byrne, Lydia; Angus, Daniel; Wiles, Janet

    2016-01-01

    While information visualization frameworks and heuristics have traditionally been reluctant to include acquired codes of meaning, designers are making use of them in a wide variety of ways. Acquired codes leverage a user's experience to understand the meaning of a visualization. They range from figurative visualizations which rely on the reader's recognition of shapes, to conventional arrangements of graphic elements which represent particular subjects. In this study, we used content analysis to codify acquired meaning in visualization. We applied the content analysis to a set of infographics and data visualizations which are exemplars of innovative and effective design. 88% of the infographics and 71% of data visualizations in the sample contain at least one use of figurative visualization. Conventions on the arrangement of graphics are also widespread in the sample. In particular, a comparison of representations of time and other quantitative data showed that conventions can be specific to a subject. These results suggest that there is a need for information visualization research to expand its scope beyond perceptual channels, to include social and culturally constructed meaning. Our paper demonstrates a viable method for identifying figurative techniques and graphic conventions and integrating them into heuristics for visualization design.

  19. Multiple Schemes for Mobile Payment Authentication Using QR Code and Visual Cryptography

    Directory of Open Access Journals (Sweden)

    Jianfeng Lu

    2017-01-01

    Full Text Available QR code (quick response code is used due to its beneficial properties, especially in the mobile payment field. However, there exists an inevitable risk in the transaction process. It is not easily perceived that the attacker tampers with or replaces the QR code that contains merchant’s beneficiary account. Thus, it is of great urgency to conduct authentication of QR code. In this study, we propose a novel mechanism based on visual cryptography scheme (VCS and aesthetic QR code, which contains three primary schemes for different concealment levels. The main steps of these schemes are as follows. Firstly, one original QR code is split into two shadows using VC multiple rules; secondly, the two shadows are embedded into the same background image, respectively, and the embedded results are fused with the same carrier QR code, respectively, using XOR mechanism of RS and QR code error correction mechanism. Finally, the two aesthetic QR codes can be stacked precisely and the original QR code is restored according to the defined VCS. Experiments corresponding to three proposed schemes are conducted and demonstrate the feasibility and security of the mobile payment authentication, the significant improvement of the concealment for the shadows in QR code, and the diversity of mobile payment authentication.

  20. Visualization of elastic wavefields computed with a finite difference code

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, S. [Lawrence Livermore National Lab., CA (United States); Harris, D.

    1994-11-15

    The authors have developed a finite difference elastic propagation model to simulate seismic wave propagation through geophysically complex regions. To facilitate debugging and to assist seismologists in interpreting the seismograms generated by the code, they have developed an X Windows interface that permits viewing of successive temporal snapshots of the (2D) wavefield as they are calculated. The authors present a brief video displaying the generation of seismic waves by an explosive source on a continent, which propagate to the edge of the continent then convert to two types of acoustic waves. This sample calculation was part of an effort to study the potential of offshore hydroacoustic systems to monitor seismic events occurring onshore.

  1. Visualization of scattering angular distributions with the SAP code

    Science.gov (United States)

    Fernandez, J. E.; Scot, V.; Basile, S.

    2010-07-01

    SAP (Scattering Angular distribution Plot) is a graphical tool developed at the University of Bologna to compute and plot Rayleigh and Compton differential cross-sections (atomic and electronic), form-factors (FFs) and incoherent scattering functions (SFs) for single elements, compounds and mixture of compounds, for monochromatic excitation in the range of 1-1000 keV. The computation of FFs and SFs may be performed in two ways: (a) by interpolating Hubbell's data from EPDL97 library and (b) by using semi-empirical formulas as described in the text. Two kinds of normalization permit to compare the plots of different magnitudes, by imposing a similar scale. The characteristics of the code SAP are illustrated with one example.

  2. Visual Studio 2010:Life Runs on Code

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    4月12日,微软在赌城拉斯维加斯发布了Visual Studio 2010(包括.NET Framework 4)正式版。发布会的主持人、微软Server & Tools部门总经理Bob Muglia使用的演讲题目是"Life Runs on Code"。这个标题的确名符其实。今天,整个世界和我们所在的社会,都是由代码以及创建这些代码的开发人员驱动的。

  3. Fast coding of orientation in primary visual cortex.

    Directory of Open Access Journals (Sweden)

    Oren Shriki

    Full Text Available Understanding how populations of neurons encode sensory information is a major goal of systems neuroscience. Attempts to answer this question have focused on responses measured over several hundred milliseconds, a duration much longer than that frequently used by animals to make decisions about the environment. How reliably sensory information is encoded on briefer time scales, and how best to extract this information, is unknown. Although it has been proposed that neuronal response latency provides a major cue for fast decisions in the visual system, this hypothesis has not been tested systematically and in a quantitative manner. Here we use a simple 'race to threshold' readout mechanism to quantify the information content of spike time latency of primary visual (V1 cortical cells to stimulus orientation. We find that many V1 cells show pronounced tuning of their spike latency to stimulus orientation and that almost as much information can be extracted from spike latencies as from firing rates measured over much longer durations. To extract this information, stimulus onset must be estimated accurately. We show that the responses of cells with weak tuning of spike latency can provide a reliable onset detector. We find that spike latency information can be pooled from a large neuronal population, provided that the decision threshold is scaled linearly with the population size, yielding a processing time of the order of a few tens of milliseconds. Our results provide a novel mechanism for extracting information from neuronal populations over the very brief time scales in which behavioral judgments must sometimes be made.

  4. Verbal vs. visual coding in modified mental imagery map exploration task

    Directory of Open Access Journals (Sweden)

    Ćirović Ivana

    2011-01-01

    Full Text Available We modified classical mental exploration task introducing verbal modality. Consequently, we could test robust effects from lexical processing in an attempt to understand whether the underlying mental representation is strictly propositional. In our three experiments, in addition to map modality (visual or verbal, lexical frequency, concreteness and visual frequency were also varied. The symbolic distance effect was replicated, regardless of map modality. Exploration of distances was regularly faster on pictorial maps. Effects of lexical frequency and concreteness were not significant for verbal maps. However, when visual frequency was introduced on pictorial maps both type of frequencies generated measurable effects. Our findings directly contradict the assumptions of propositional theories (1 subjects were faster in the visual modality, which would be difficult to explain if the perceptual code had to be transformed into propositional, (2 word frequency and concreteness did not contribute as would be expected if propositional code were a default.

  5. Efficient Quantum Private Communication Based on Dynamic Control Code Sequence

    Science.gov (United States)

    Cao, Zheng-Wen; Feng, Xiao-Yi; Peng, Jin-Ye; Zeng, Gui-Hua; Qi, Jin

    2016-12-01

    Based on chaos and quantum properties, we propose a quantum private communication scheme with dynamic control code sequence. The initial sequence is obtained via chaotic systems, and the control code sequence is derived by grouping, XOR and extracting. A shift cycle algorithm is designed to enable the dynamic change of control code sequence. Analysis shows that transmission efficiency could reach 100 % with high dynamics and security.

  6. Efficient Quantum Private Communication Based on Dynamic Control Code Sequence

    Science.gov (United States)

    Cao, Zheng-Wen; Feng, Xiao-Yi; Peng, Jin-Ye; Zeng, Gui-Hua; Qi, Jin

    2017-04-01

    Based on chaos and quantum properties, we propose a quantum private communication scheme with dynamic control code sequence. The initial sequence is obtained via chaotic systems, and the control code sequence is derived by grouping, XOR and extracting. A shift cycle algorithm is designed to enable the dynamic change of control code sequence. Analysis shows that transmission efficiency could reach 100 % with high dynamics and security.

  7. Impaired letter-string processing in developmental dyslexia: what visual-to-phonology code mapping disorder?

    Science.gov (United States)

    Valdois, Sylviane; Lassus-Sangosse, Delphine; Lobier, Muriel

    2012-05-01

    Poor parallel letter-string processing in developmental dyslexia was taken as evidence of poor visual attention (VA) span, that is, a limitation of visual attentional resources that affects multi-character processing. However, the use of letter stimuli in oral report tasks was challenged on its capacity to highlight a VA span disorder. In particular, report of poor letter/digit-string processing but preserved symbol-string processing was viewed as evidence of poor visual-to-phonology code mapping, in line with the phonological theory of developmental dyslexia. We assessed here the visual-to-phonological-code mapping disorder hypothesis. In Experiment 1, letter-string, digit-string and colour-string processing was assessed to disentangle a phonological versus visual familiarity account of the letter/digit versus symbol dissociation. Against a visual-to-phonological-code mapping disorder but in support of a familiarity account, results showed poor letter/digit-string processing but preserved colour-string processing in dyslexic children. In Experiment 2, two tasks of letter-string report were used, one of which was performed simultaneously to a high-taxing phonological task. Results show that dyslexic children are similarly impaired in letter-string report whether a concurrent phonological task is simultaneously performed or not. Taken together, these results provide strong evidence against a phonological account of poor letter-string processing in developmental dyslexia.

  8. Implementation of Energy Code Controls Requirements in New Commercial Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, Michael I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hart, Philip R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hatten, Mike [Solarc Energy Group, LLC, Seattle, WA (United States); Jones, Dennis [Group 14 Engineering, Inc., Denver, CO (United States); Cooper, Matthew [Group 14 Engineering, Inc., Denver, CO (United States)

    2017-03-24

    Most state energy codes in the United States are based on one of two national model codes; ANSI/ASHRAE/IES 90.1 (Standard 90.1) or the International Code Council (ICC) International Energy Conservation Code (IECC). Since 2004, covering the last four cycles of Standard 90.1 updates, about 30% of all new requirements have been related to building controls. These requirements can be difficult to implement and verification is beyond the expertise of most building code officials, yet the assumption in studies that measure the savings from energy codes is that they are implemented and working correctly. The objective of the current research is to evaluate the degree to which high impact controls requirements included in commercial energy codes are properly designed, commissioned and implemented in new buildings. This study also evaluates the degree to which these control requirements are realizing their savings potential. This was done using a three-step process. The first step involved interviewing commissioning agents to get a better understanding of their activities as they relate to energy code required controls measures. The second involved field audits of a sample of commercial buildings to determine whether the code required control measures are being designed, commissioned and correctly implemented and functioning in new buildings. The third step includes compilation and analysis of the information gather during the first two steps. Information gathered during these activities could be valuable to code developers, energy planners, designers, building owners, and building officials.

  9. Next generation Zero-Code control system UI

    CERN Document Server

    CERN. Geneva

    2017-01-01

    Developing ergonomic user interfaces for control systems is challenging, especially during machine upgrade and commissioning where several small changes may suddenly be required. Zero-code systems, such as *Inspector*, provide agile features for creating and maintaining control system interfaces. More so, these next generation Zero-code systems bring simplicity and uniformity and brake the boundaries between Users and Developers. In this talk we present *Inspector*, a CERN made Zero-code application development system, and we introduce the major differences and advantages of using Zero-code control systems to develop operational UI.

  10. Connectivity Reveals Sources of Predictive Coding Signals in Early Visual Cortex During Processing of Visual Optic Flow.

    Science.gov (United States)

    Schindler, Andreas; Bartels, Andreas

    2016-05-24

    Superimposed on the visual feed-forward pathway, feedback connections convey higher level information to cortical areas lower in the hierarchy. A prominent framework for these connections is the theory of predictive coding where high-level areas send stimulus interpretations to lower level areas that compare them with sensory input. Along these lines, a growing body of neuroimaging studies shows that predictable stimuli lead to reduced blood oxygen level-dependent (BOLD) responses compared with matched nonpredictable counterparts, especially in early visual cortex (EVC) including areas V1-V3. The sources of these modulatory feedback signals are largely unknown. Here, we re-examined the robust finding of relative BOLD suppression in EVC evident during processing of coherent compared with random motion. Using functional connectivity analysis, we show an optic flow-dependent increase of functional connectivity between BOLD suppressed EVC and a network of visual motion areas including MST, V3A, V6, the cingulate sulcus visual area (CSv), and precuneus (Pc). Connectivity decreased between EVC and 2 areas known to encode heading direction: entorhinal cortex (EC) and retrosplenial cortex (RSC). Our results provide first evidence that BOLD suppression in EVC for predictable stimuli is indeed mediated by specific high-level areas, in accord with the theory of predictive coding.

  11. Quality of visual sewer inspection data: The need for a new coding system?! (poster)

    NARCIS (Netherlands)

    Dirksen, J.; Van der Steen, A.; Langeveld, J.G.; Clemens, F.H.L.R.

    2013-01-01

    Previous research learned that the reproducibility of visual sewer inspection data is poor (Dirksen et al.). Further research by Arjan et al. showed that the applied coding system has a major influence on the reproducibility. The aim of this study was to give relevant suggestions to improve the qual

  12. Deciphering the genetic regulatory code using an inverse error control coding framework.

    Energy Technology Data Exchange (ETDEWEB)

    Rintoul, Mark Daniel; May, Elebeoba Eni; Brown, William Michael; Johnston, Anna Marie; Watson, Jean-Paul

    2005-03-01

    We have found that developing a computational framework for reconstructing error control codes for engineered data and ultimately for deciphering genetic regulatory coding sequences is a challenging and uncharted area that will require advances in computational technology for exact solutions. Although exact solutions are desired, computational approaches that yield plausible solutions would be considered sufficient as a proof of concept to the feasibility of reverse engineering error control codes and the possibility of developing a quantitative model for understanding and engineering genetic regulation. Such evidence would help move the idea of reconstructing error control codes for engineered and biological systems from the high risk high payoff realm into the highly probable high payoff domain. Additionally this work will impact biological sensor development and the ability to model and ultimately develop defense mechanisms against bioagents that can be engineered to cause catastrophic damage. Understanding how biological organisms are able to communicate their genetic message efficiently in the presence of noise can improve our current communication protocols, a continuing research interest. Towards this end, project goals include: (1) Develop parameter estimation methods for n for block codes and for n, k, and m for convolutional codes. Use methods to determine error control (EC) code parameters for gene regulatory sequence. (2) Develop an evolutionary computing computational framework for near-optimal solutions to the algebraic code reconstruction problem. Method will be tested on engineered and biological sequences.

  13. Neural Network Controlled Visual Saccades

    Science.gov (United States)

    Johnson, Jeffrey D.; Grogan, Timothy A.

    1989-03-01

    The paper to be presented will discuss research on a computer vision system controlled by a neural network capable of learning through classical (Pavlovian) conditioning. Through the use of unconditional stimuli (reward and punishment) the system will develop scan patterns of eye saccades necessary to differentiate and recognize members of an input set. By foveating only those portions of the input image that the system has found to be necessary for recognition the drawback of computational explosion as the size of the input image grows is avoided. The model incorporates many features found in animal vision systems, and is governed by understandable and modifiable behavior patterns similar to those reported by Pavlov in his classic study. These behavioral patterns are a result of a neuronal model, used in the network, explicitly designed to reproduce this behavior.

  14. In Vivo Imaging Reveals Composite Coding for Diagonal Motion in the Drosophila Visual System

    Science.gov (United States)

    Zhou, Wei; Chang, Jin

    2016-01-01

    Understanding information coding is important for resolving the functions of visual neural circuits. The motion vision system is a classic model for studying information coding as it contains a concise and complete information-processing circuit. In Drosophila, the axon terminals of motion-detection neurons (T4 and T5) project to the lobula plate, which comprises four regions that respond to the four cardinal directions of motion. The lobula plate thus represents a topographic map on a transverse plane. This enables us to study the coding of diagonal motion by investigating its response pattern. By using in vivo two-photon calcium imaging, we found that the axon terminals of T4 and T5 cells in the lobula plate were activated during diagonal motion. Further experiments showed that the response to diagonal motion is distributed over the following two regions compared to the cardinal directions of motion—a diagonal motion selective response region and a non-selective response region—which overlap with the response regions of the two vector-correlated cardinal directions of motion. Interestingly, the sizes of the non-selective response regions are linearly correlated with the angle of the diagonal motion. These results revealed that the Drosophila visual system employs a composite coding for diagonal motion that includes both independent coding and vector decomposition coding. PMID:27695103

  15. Decoding of responses to mixed frequency and phase coded visual stimuli using multiset canonical correlation analysis.

    Science.gov (United States)

    Suefusa, Kaori; Tanaka, Toshihisa

    2016-08-01

    Brain-computer interfacing (BCI) based on steady-state visual evoked potentials (SSVEPs) is one of the most practical BCIs because of its high recognition accuracies and little training of a user. Mixed frequency and phase coding which can implement a number of commands and achieve a high information transfer rate (ITR) has recently been gaining much attention. In order to implement mixed-coded SSVEP-BCI as a reliable interface, it is important to detect commands fast and accurately. This paper presents a novel method to recognize mixed-coded SSVEPs which achieves high performance. The method employs multiset canonical correlation analysis to obtain spatial filters which enhance SSVEP components. An experiment with a mixed-coded SSVEP-BCI was conducted to evaluate performance of the proposed method compared with the previous work. The experimental results showed that the proposed method achieved significantly higher command recognition accuracy and ITR than the state-of-the-art.

  16. Polarization-controlled anisotropic coding metamaterials at terahertz frequencies

    CERN Document Server

    Liu, Shuo; Xu, Quan; Bao, Di; Du, Liangliang; Wan, Xiang; Tang, Wen Xuan; Ouyang, Chunmei; Zhou, Xiao Yang; Yuan, Hao; Ma, Hui Feng; Jiang, Wei Xiang; Han, Jiaguang; Zhang, Weili; Cheng, Qiang

    2015-01-01

    Metamaterials based on effective media have achieved a lot of unusual physics (e.g. negative refraction and invisibility cloaking) owing to their abilities to tailor the effective medium parameters that do not exist in nature. Recently, coding metamaterials have been suggested to control electromagnetic waves by designing the coding sequences of digital elements '0' and '1', which possess opposite phase responses. Here, we propose the concept of anisotropic coding metamaterial at terahertz frequencies, in which coding behaviors in different directions are dependent on the polarization status of terahertz waves. We experimentally demonstrate an ultrathin and flexible polarization-controlled anisotropic coding metasurface functioning in the terahertz regime using specially- designed coding elements. By encoding the elements with elaborately-designed digital sequences (in both 1 bit and 2 bits), the x- and y-polarized reflected waves can be deflected or diffused independently in three dimensions. The simulated f...

  17. Hierarchical Novelty-Familiarity Representation in the Visual System by Modular Predictive Coding.

    Science.gov (United States)

    Vladimirskiy, Boris; Urbanczik, Robert; Senn, Walter

    2015-01-01

    Predictive coding has been previously introduced as a hierarchical coding framework for the visual system. At each level, activity predicted by the higher level is dynamically subtracted from the input, while the difference in activity continuously propagates further. Here we introduce modular predictive coding as a feedforward hierarchy of prediction modules without back-projections from higher to lower levels. Within each level, recurrent dynamics optimally segregates the input into novelty and familiarity components. Although the anatomical feedforward connectivity passes through the novelty-representing neurons, it is nevertheless the familiarity information which is propagated to higher levels. This modularity results in a twofold advantage compared to the original predictive coding scheme: the familiarity-novelty representation forms quickly, and at each level the full representational power is exploited for an optimized readout. As we show, natural images are successfully compressed and can be reconstructed by the familiarity neurons at each level. Missing information on different spatial scales is identified by novelty neurons and complements the familiarity representation. Furthermore, by virtue of the recurrent connectivity within each level, non-classical receptive field properties still emerge. Hence, modular predictive coding is a biologically realistic metaphor for the visual system that dynamically extracts novelty at various scales while propagating the familiarity information.

  18. Visualizing the software system towards identifying the topic from source code using semantic clustering

    Directory of Open Access Journals (Sweden)

    Kanchan Sharma

    2014-03-01

    Full Text Available In software re-engineering, domain knowledge are valuable source of information for developers. Here, we describe how the coding standards are helpful for the identification of domain while writing the source code. Internal comments and logical identifier names in source code are the key source to find the concept and domain area for the application. One of the Information retrieval techniques, Latent Semantic Indexing (LSI uses this linguistic information such as identifier names and comments in source code to map it with the domain name. Based on the linguistic results from LSI engine, a clustering technique used to group source artifacts that use similar vocabulary and a way of representing complex system into simpler components. It works at the source code textual level and making it language independent. Prior research activity correlated the semantics with structural information and applied it at different level of abstraction. Based on the frequency of the domain terms labeling has been provided after discrete characterization of the clusters, using machine learning and visually explored. Visualization makes the concept detection much easier.

  19. Reliability-based automatic repeat request for short code modulation visual evoked potentials in brain computer interfaces.

    Science.gov (United States)

    Sato, Jun-Ichi; Washizawa, Yoshikazu

    2015-08-01

    We propose two methods to improve code modulation visual evoked potential brain computer interfaces (cVEP BCIs). Most of BCIs average brain signals from several trials in order to improve the classification performance. The number of averaging defines the trade-off between input speed and accuracy, and the optimal averaging number depends on individual, signal acquisition system, and so forth. Firstly, we propose a novel dynamic method to estimate the averaging number for cVEP BCIs. The proposed method is based on the automatic repeat request (ARQ) that is used in communication systems. The existing cVEP BCIs employ rather longer code, such as 63-bit M-sequence. The code length also defines the trade-off between input speed and accuracy. Since the reliability of the proposed BCI can be controlled by the proposed ARQ method, we introduce shorter codes, 32-bit M-sequence and the Kasami-sequence. Thanks to combine the dynamic averaging number estimation method and the shorter codes, the proposed system exhibited higher information transfer rate compared to existing cVEP BCIs.

  20. Visual cues for manual control of headway.

    Science.gov (United States)

    Hosking, Simon G; Davey, Catherine E; Kaiser, Mary K

    2013-01-01

    The ability to maintain appropriate gaps to objects in one's environment is important when navigating through a three-dimensional world. Previous research has shown that the visual angle subtended by a lead/approaching object and its rate of change are important variables for timing interceptions, collision avoidance, continuous regulation of braking, and manual control of headway. However, investigations of headway maintenance have required participants to maintain a fixed distance headway and have not investigated how information about own-speed is taken into account. In the following experiment, we asked participants to use a joystick to follow computer-simulated lead objects. The results showed that ground texture, following speed, and the size of the lead object had significant effects on both mean following distances and following distance variance. Furthermore, models of the participants' joystick responses provided better fits when it was assumed that the desired visual extent of the lead object would vary over time. Taken together, the results indicate that while information about own-speed is used by controllers to set the desired headway to a lead object, the continuous regulation of headway is influenced primarily by the visual angle of the lead object and its rate of change. The reliance on visual angle, its rate of change, and/or own-speed information also varied depending on the control dynamics of the system. Such findings are consistent with an optimal control criterion that reflects a differential weighting on different sources of information depending on the plant dynamics. As in other judgements of motion in depth, the information used for controlling headway to other objects in the environment varies depending on the constraints of the task and different strategies of control.

  1. Independent Source Coding for Control over Noiseless Channels

    DEFF Research Database (Denmark)

    da Silva, Eduardo; Derpich, Milan; Østergaard, Jan

    2010-01-01

    By focusing on a class of source coding schemes built around entropy coded dithered quantizers, we develop a framework to deal with average data-rate constraints in a tractable manner that combines ideas from both information and control theories. We focus on a situation where a noisy linear system...

  2. Visual cues for manual control of headway

    Directory of Open Access Journals (Sweden)

    Simon eHosking

    2013-05-01

    Full Text Available The ability to maintain appropriate gaps to objects in one's environment is important when navigating through a three-dimensional world. Previous research has shown that the visual angle subtended by a lead/approaching object and its rate of change are important variables for timing interceptions, collision avoidance, continuous regulation of braking, and manual control of headway. However, investigations of headway maintenance have required participants to maintain a fixed following distance and have notinvestigated how information about speed is taken into account. In the following experiment, we asked participants to use a joystick to follow computer-simulated lead objects. The results showed that ground texture, following speed, and the size of the lead object had significant effects on both mean following distances and following distance variance. Furthermore, models of the participants' joystick responses provided better fits when it was assumed that the desired visual extent of the lead object would vary over time. Taken together, the results indicate that while information about own-speed is used by controllers to set the desired headway to a lead object, the continuous regulation of headway is influenced primarily by the visual angle of the lead object and its rate of change. The reliance on visual angle, its rate of change, and/or own-speed information also varied depending on the controldynamics of the system. Such findings are consistent with an optimal control criterion that reflects a differential weighting on different sources of information depending on the plant dynamics. As in other judgements of motion in depth, the information used for controlling headway to other objects in the environment varies depending on the constraints of the task and different strategies of control.

  3. Controlling Energy Radiations of Electromagnetic Waves via Frequency Coding Metamaterials.

    Science.gov (United States)

    Wu, Haotian; Liu, Shuo; Wan, Xiang; Zhang, Lei; Wang, Dan; Li, Lianlin; Cui, Tie Jun

    2017-09-01

    Metamaterials are artificial structures composed of subwavelength unit cells to control electromagnetic (EM) waves. The spatial coding representation of metamaterial has the ability to describe the material in a digital way. The spatial coding metamaterials are typically constructed by unit cells that have similar shapes with fixed functionality. Here, the concept of frequency coding metamaterial is proposed, which achieves different controls of EM energy radiations with a fixed spatial coding pattern when the frequency changes. In this case, not only different phase responses of the unit cells are considered, but also different phase sensitivities are also required. Due to different frequency sensitivities of unit cells, two units with the same phase response at the initial frequency may have different phase responses at higher frequency. To describe the frequency coding property of unit cell, digitalized frequency sensitivity is proposed, in which the units are encoded with digits "0" and "1" to represent the low and high phase sensitivities, respectively. By this merit, two degrees of freedom, spatial coding and frequency coding, are obtained to control the EM energy radiations by a new class of frequency-spatial coding metamaterials. The above concepts and physical phenomena are confirmed by numerical simulations and experiments.

  4. Asynchrony adaptation reveals neural population code for audio-visual timing.

    Science.gov (United States)

    Roach, Neil W; Heron, James; Whitaker, David; McGraw, Paul V

    2011-05-01

    The relative timing of auditory and visual stimuli is a critical cue for determining whether sensory signals relate to a common source and for making inferences about causality. However, the way in which the brain represents temporal relationships remains poorly understood. Recent studies indicate that our perception of multisensory timing is flexible--adaptation to a regular inter-modal delay alters the point at which subsequent stimuli are judged to be simultaneous. Here, we measure the effect of audio-visual asynchrony adaptation on the perception of a wide range of sub-second temporal relationships. We find distinctive patterns of induced biases that are inconsistent with the previous explanations based on changes in perceptual latency. Instead, our results can be well accounted for by a neural population coding model in which: (i) relative audio-visual timing is represented by the distributed activity across a relatively small number of neurons tuned to different delays; (ii) the algorithm for reading out this population code is efficient, but subject to biases owing to under-sampling; and (iii) the effect of adaptation is to modify neuronal response gain. These results suggest that multisensory timing information is represented by a dedicated population code and that shifts in perceived simultaneity following asynchrony adaptation arise from analogous neural processes to well-known perceptual after-effects.

  5. Argonne Code Center numerical control postprocessor inventory

    Energy Technology Data Exchange (ETDEWEB)

    Vollink, S. (comp.)

    1977-12-21

    A survey to identify numerical control postprocessors available at Department of Energy facilities is reported. The data are presented in the body of the report under the postprocessor identification. Information supplied includes the vendor name and address, the N/C and postprocessor languages, the machine tools and control unit supported, the computers used, and the identification of the DOE installation. The body of the report is followed by five indexes permitting users to refer to the postprocessor data by product number, DOE installation, machine tool, control unit, or computer. (RWR)

  6. Color Coding Organic Chemicals for Inventory Control.

    Science.gov (United States)

    Wystrach, V. P.; George, Babu

    1985-01-01

    Describes a system in which organic chemicals are recoded for inventory control and reshelving purposes. The system works well in undergraduate organic chemistry or biology laboratories but can be expanded to handle a larger and more complicated inventory. (JN)

  7. Neuronal population coding of perceived and memorized visual features in the lateral prefrontal cortex

    Science.gov (United States)

    Mendoza-Halliday, Diego; Martinez-Trujillo, Julio C.

    2017-01-01

    The primate lateral prefrontal cortex (LPFC) encodes visual stimulus features while they are perceived and while they are maintained in working memory. However, it remains unclear whether perceived and memorized features are encoded by the same or different neurons and population activity patterns. Here we record LPFC neuronal activity while monkeys perceive the motion direction of a stimulus that remains visually available, or memorize the direction if the stimulus disappears. We find neurons with a wide variety of combinations of coding strength for perceived and memorized directions: some neurons encode both to similar degrees while others preferentially or exclusively encode either one. Reading out the combined activity of all neurons, a machine-learning algorithm reliably decode the motion direction and determine whether it is perceived or memorized. Our results indicate that a functionally diverse population of LPFC neurons provides a substrate for discriminating between perceptual and mnemonic representations of visual features. PMID:28569756

  8. Visualizing how Seismic Waves Propagate Across Seismic Arrays using the IRIS DMS Ground Motion Visualization (GMV) Products and Codes

    Science.gov (United States)

    Taber, J.; Bahavar, M.; Bravo, T. K.; Butler, R. F.; Kilb, D. L.; Trabant, C.; Woodward, R.; Ammon, C. J.

    2011-12-01

    Data from dense seismic arrays can be used to visualize the propagation of seismic waves, resulting in animations effective for teaching both general and advanced audiences. One of the first visualizations of this type was developed using Objective C code and EarthScope/USArray data, which was then modified and ported to the Matlab platform and has now been standardized and automated as an IRIS Data Management System (IRIS-DMS) data product. These iterative code developments and improvements were completed by C. Ammon, R. Woodward and M. Bahavar, respectively. Currently, an automated script creates Ground Motion Visualizations (GMVs) for all global earthquakes over magnitude 6 recorded by EarthScope's USArray Transportable Array (USArray TA) network. The USArray TA network is a rolling array of 400 broadband stations deployed on a uniform 70-km grid. These near real-time GMV visualizations are typically available for download within 4 hours or less of their occurrence (see: www.iris.edu/dms/products/usarraygmv/). The IRIS-DMS group has recently added a feature that allows users to highlight key elements within the GMVs, by providing an online tool for creating customized GMVs. This new interface allows users to select the stations, channels, and time window of interest, adjust the mapped areal extent of the view, and specify high and low pass filters. An online tutorial available from the IRIS Education and Public Outreach (IRIS-EPO) website, listed below, steps through a teaching sequence that can be used to explain the basic features of the GMVs. For example, they can be used to demonstrate simple concepts such as relative P, S and surface wave velocities and corresponding wavelengths for middle-school students, or more advanced concepts such as the influence of focal mechanism on waveforms, or how seismic waves converge at an earthquake's antipode. For those who desire a greater level of customization, including the ability to use the GMV framework with data

  9. Nine-year-old children use norm-based coding to visually represent facial expression.

    Science.gov (United States)

    Burton, Nichola; Jeffery, Linda; Skinner, Andrew L; Benton, Christopher P; Rhodes, Gillian

    2013-10-01

    Children are less skilled than adults at making judgments about facial expression. This could be because they have not yet developed adult-like mechanisms for visually representing faces. Adults are thought to represent faces in a multidimensional face-space, and have been shown to code the expression of a face relative to the norm or average face in face-space. Norm-based coding is economical and adaptive, and may be what makes adults more sensitive to facial expression than children. This study investigated the coding system that children use to represent facial expression. An adaptation aftereffect paradigm was used to test 24 adults and 18 children (9 years 2 months to 9 years 11 months old). Participants adapted to weak and strong antiexpressions. They then judged the expression of an average expression. Adaptation created aftereffects that made the test face look like the expression opposite that of the adaptor. Consistent with the predictions of norm-based but not exemplar-based coding, aftereffects were larger for strong than weak adaptors for both age groups. Results indicate that, like adults, children's coding of facial expressions is norm-based.

  10. Visual operations control in administrative environments

    Energy Technology Data Exchange (ETDEWEB)

    Carson, M.L.; Levine, L.O.

    1995-03-01

    When asked what comes to mind when they think of ``controlling work`` in the office, people may respond with ``overbearing boss,`` ``no autonomy,`` or ``Theory X management.`` The idea of controlling work in white collar or administrative environments can have a negative connotation. However, office life is often chaotic and miserable precisely because the work processes are out of control, and managers must spend their time looking over people`s shoulders and fighting fires. While management styles and structures vary, the need for control of work processes does not. Workers in many environments are being reorganized into self-managed work teams. These teams are expected to manage their own work through increased autonomy and empowerment. However, even empowered work teams must manage their work processes because of process variation. The amount of incoming jobs vary with both expected (seasonal) and unexpected demand. The mixture of job types vary over time, changing the need for certain skills or knowledge. And illness and turnover affect the availability of workers with needed skills and knowledge. Clearly, there is still a need to control work, whether the authority for controlling work is vested in one person or many. Visual control concepts provide simple, inexpensive, and flexible mechanisms for managing processes in work teams and continuous improvement administrative environments.

  11. ROCIT : a visual object recognition algorithm based on a rank-order coding scheme.

    Energy Technology Data Exchange (ETDEWEB)

    Gonzales, Antonio Ignacio; Reeves, Paul C.; Jones, John J.; Farkas, Benjamin D.

    2004-06-01

    This document describes ROCIT, a neural-inspired object recognition algorithm based on a rank-order coding scheme that uses a light-weight neuron model. ROCIT coarsely simulates a subset of the human ventral visual stream from the retina through the inferior temporal cortex. It was designed to provide an extensible baseline from which to improve the fidelity of the ventral stream model and explore the engineering potential of rank order coding with respect to object recognition. This report describes the baseline algorithm, the model's neural network architecture, the theoretical basis for the approach, and reviews the history of similar implementations. Illustrative results are used to clarify algorithm details. A formal benchmark to the 1998 FERET fafc test shows above average performance, which is encouraging. The report concludes with a brief review of potential algorithmic extensions for obtaining scale and rotational invariance.

  12. Technical justification for ASME code section xi crack detection by visual examination

    Energy Technology Data Exchange (ETDEWEB)

    Nickell, R.E. [Applied Science and Technology, Poway, CA (United States); Rashid, Y.R. [ANATECH Corp., San Diego (United States)

    2001-07-01

    A critical technical element of nuclear power plant license renewal in the United States is the demonstration that the effects of aging do not compromise the intended safety function(s) of a system, structure, or component during the extended term of operation. The demonstration may take either of two forms. First, it can be shown that the design basis for the system, structure, or component is sufficiently robust that the aging effects have been insignificant through the current license term, and will continue to be insignificant through the extended term. Alternatively, it can be shown that, while the aging effects may be potentially significant, those effects can be managed and functionality maintained by defined programmatic activities during the extended term of operation. The first of the two approaches is generally provided by the construction basis, such as construction in accordance with the ASME Code Section III and other consensus codes and standards. The second of the two approaches is often provided by periodic inservice inspection and testing, in accordance with the ASME Code Section XI. The purpose of the ASME Section XI inspections and tests is to assure that systems, components, and structures are fit for continued service until the next scheduled inspection or test. The purpose of this paper is to document the effectiveness of the current ASME Code Section XI visual examination procedures in detecting the effects of aging for systems, structures, and components that are tolerant of mature cracks. (author)

  13. Compressive Sampling based Image Coding for Resource-deficient Visual Communication.

    Science.gov (United States)

    Liu, Xianming; Zhai, Deming; Zhou, Jiantao; Zhang, Xinfeng; Zhao, Debin; Gao, Wen

    2016-04-14

    In this paper, a new compressive sampling based image coding scheme is developed to achieve competitive coding efficiency at lower encoder computational complexity, while supporting error resilience. This technique is particularly suitable for visual communication with resource-deficient devices. At the encoder, compact image representation is produced, which is a polyphase down-sampled version of the input image; but the conventional low-pass filter prior to down-sampling is replaced by a local random binary convolution kernel. The pixels of the resulting down-sampled pre-filtered image are local random measurements and placed in the original spatial configuration. The advantages of local random measurements are two folds: 1) preserve high-frequency image features that are otherwise discarded by low-pass filtering; 2) remain a conventional image and can therefore be coded by any standardized codec to remove statistical redundancy of larger scales. Moreover, measurements generated by different kernels can be considered as multiple descriptions of the original image and therefore the proposed scheme has the advantage of multiple description coding. At the decoder, a unified sparsity-based soft-decoding technique is developed to recover the original image from received measurements in a framework of compressive sensing. Experimental results demonstrate that the proposed scheme is competitive compared with existing methods, with a unique strength of recovering fine details and sharp edges at low bit-rates.

  14. A neurophysiologically plausible population code model for feature integration explains visual crowding.

    Directory of Open Access Journals (Sweden)

    Ronald van den Berg

    2010-01-01

    Full Text Available An object in the peripheral visual field is more difficult to recognize when surrounded by other objects. This phenomenon is called "crowding". Crowding places a fundamental constraint on human vision that limits performance on numerous tasks. It has been suggested that crowding results from spatial feature integration necessary for object recognition. However, in the absence of convincing models, this theory has remained controversial. Here, we present a quantitative and physiologically plausible model for spatial integration of orientation signals, based on the principles of population coding. Using simulations, we demonstrate that this model coherently accounts for fundamental properties of crowding, including critical spacing, "compulsory averaging", and a foveal-peripheral anisotropy. Moreover, we show that the model predicts increased responses to correlated visual stimuli. Altogether, these results suggest that crowding has little immediate bearing on object recognition but is a by-product of a general, elementary integration mechanism in early vision aimed at improving signal quality.

  15. A neurophysiologically plausible population code model for feature integration explains visual crowding.

    Science.gov (United States)

    van den Berg, Ronald; Roerdink, Jos B T M; Cornelissen, Frans W

    2010-01-22

    An object in the peripheral visual field is more difficult to recognize when surrounded by other objects. This phenomenon is called "crowding". Crowding places a fundamental constraint on human vision that limits performance on numerous tasks. It has been suggested that crowding results from spatial feature integration necessary for object recognition. However, in the absence of convincing models, this theory has remained controversial. Here, we present a quantitative and physiologically plausible model for spatial integration of orientation signals, based on the principles of population coding. Using simulations, we demonstrate that this model coherently accounts for fundamental properties of crowding, including critical spacing, "compulsory averaging", and a foveal-peripheral anisotropy. Moreover, we show that the model predicts increased responses to correlated visual stimuli. Altogether, these results suggest that crowding has little immediate bearing on object recognition but is a by-product of a general, elementary integration mechanism in early vision aimed at improving signal quality.

  16. The Visual Text: Bibliographic Codes as Pragmatic Markers on a Manuscript Page

    Directory of Open Access Journals (Sweden)

    Rogos-Hebda Justyna

    2016-12-01

    Full Text Available This paper explores the dynamics of the textual-visual interface of a medieval manuscript page within the frameworks of historical pragmatics and pragmaphilological approaches to the study of historical texts. Whilst the former focuses on the contexts in which historical utterances, manifested as texts, occur (Jacobs & Jucker 1995: 11, the latter involves a context-based perspective in the study of individual historical texts (Jucker 2000: 91. Combining the two approaches allows for a more comprehensive study of the “visual text” (cf. Machan 2011 than has been possible for paleographic, codicological, or linguistic analyses of medieval manuscripts. The present paper adopts the “pragmatics-on-the-page” approach (cf. Carroll et al. 2013, Peikola et al. 2014 in its analysis of bibliographic codes in British Library Royal MS 18 D II, which contains the texts of Lydgate’s Troy Book and Siege of Thebes. Such visual elements of the manuscript page as mise en page, ink colour, as well as type and size of script will be examined as pragmatic markers, functioning on three levels of meaning: textual, interactional, and metalinguistic (cf. Erman 2001, Carroll et al. 2013, and providing (visual contexts for interpreting the linguistic message of the text.

  17. Real-time distributed video coding for 1K-pixel visual sensor networks

    Science.gov (United States)

    Hanca, Jan; Deligiannis, Nikos; Munteanu, Adrian

    2016-07-01

    Many applications in visual sensor networks (VSNs) demand the low-cost wireless transmission of video data. In this context, distributed video coding (DVC) has proven its potential to achieve state-of-the-art compression performance while maintaining low computational complexity of the encoder. Despite their proven capabilities, current DVC solutions overlook hardware constraints, and this renders them unsuitable for practical implementations. This paper introduces a DVC architecture that offers highly efficient wireless communication in real-world VSNs. The design takes into account the severe computational and memory constraints imposed by practical implementations on low-resolution visual sensors. We study performance-complexity trade-offs for feedback-channel removal, propose learning-based techniques for rate allocation, and investigate various simplifications of side information generation yielding real-time decoding. The proposed system is evaluated against H.264/AVC intra, Motion-JPEG, and our previously designed DVC prototype for low-resolution visual sensors. Extensive experimental results on various data show significant improvements in multiple configurations. The proposed encoder achieves real-time performance on a 1k-pixel visual sensor mote. Real-time decoding is performed on a Raspberry Pi single-board computer or a low-end notebook PC. To the best of our knowledge, the proposed codec is the first practical DVC deployment on low-resolution VSNs.

  18. Visual Determination of Conjugate Eye Deviation on Computed Tomography Scan Predicts Diagnosis of Stroke Code Patients.

    Science.gov (United States)

    Spokoyny, Ilana; Chen, James Y; Raman, Rema; Ernstrom, Karin; Agrawal, Kunal; Modir, Royya F; Meyer, Dawn M; Meyer, Brett C

    2016-12-01

    Head computed tomography (CT) is critical for stroke code evaluations and often happens prior to completion of the neurological exam. Eye deviation on neuroimaging (DeyeCOM sign) has utility for predicting stroke diagnosis and correlates with National Institutes of Health Stroke Scale (NIHSS) gaze score. We further assessed the utility of the DeyeCOM sign, without complex caliper-based eye deviation calculations, but simply with a visual determination method. Patients with initial head CT and final diagnosis from an institutional review board-approved consecutive prospective registry of stroke codes at the University of California, San Diego, were included. Five stroke specialists and 1 neuroradiologist reviewed each CT. DeyeCOM+ patients were compared to DeyeCOM- patients (baseline characteristics, diagnosis, and NIHSS gaze score). Kappa statistics compared stroke specialists to neuroradiologist reads, and visual determination to caliper measurement of DeyeCOM sign. Of 181 patients, 46 were DeyeCOM+. Ischemic stroke was more commonly diagnosed in DeyeCOM+ patients compared to other diagnoses (P = .039). DeyeCOM+ patients were more likely to have an NIHSS gaze score of 1 or higher (P = .006). The NIHSS score of DeyeCOM+ stroke versus DeyeCOM- stroke patients was 8.3 ± 6.0 versus 6.7 ± 8.0 (P = .065). Functional outcomes were similar (P = .59). Stroke specialists had excellent agreement with the neuroradiologist (Κ = .89). Visual inspection had excellent agreement with the caliper method (Κ = .88). Using a time-sensitive visual determination of gaze deviation on imaging was predictive of ischemic stroke diagnosis and presence of NIHSS gaze score, and was consistent with the more complex caliper method. This study furthers the clinical utility of the DeyeCOM sign for predicting ischemic strokes. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  19. An electrocorticographic BCI using code-based VEP for control in video applications: a single-subject study.

    Science.gov (United States)

    Kapeller, Christoph; Kamada, Kyousuke; Ogawa, Hiroshi; Prueckl, Robert; Scharinger, Josef; Guger, Christoph

    2014-01-01

    A brain-computer-interface (BCI) allows the user to control a device or software with brain activity. Many BCIs rely on visual stimuli with constant stimulation cycles that elicit steady-state visual evoked potentials (SSVEP) in the electroencephalogram (EEG). This EEG response can be generated with a LED or a computer screen flashing at a constant frequency, and similar EEG activity can be elicited with pseudo-random stimulation sequences on a screen (code-based BCI). Using electrocorticography (ECoG) instead of EEG promises higher spatial and temporal resolution and leads to more dominant evoked potentials due to visual stimulation. This work is focused on BCIs based on visual evoked potentials (VEP) and its capability as a continuous control interface for augmentation of video applications. One 35 year old female subject with implanted subdural grids participated in the study. The task was to select one out of four visual targets, while each was flickering with a code sequence. After a calibration run including 200 code sequences, a linear classifier was used during an evaluation run to identify the selected visual target based on the generated code-based VEPs over 20 trials. Multiple ECoG buffer lengths were tested and the subject reached a mean online classification accuracy of 99.21% for a window length of 3.15 s. Finally, the subject performed an unsupervised free run in combination with visual feedback of the current selection. Additionally, an algorithm was implemented that allowed to suppress false positive selections and this allowed the subject to start and stop the BCI at any time. The code-based BCI system attained very high online accuracy, which makes this approach very promising for control applications where a continuous control signal is needed.

  20. mRNAs coding for neurotransmitter receptors and voltage-gated sodium channels in the adult rabbit visual cortex after monocular deafferentiation

    Science.gov (United States)

    Nguyen, Quoc-Thang; Matute, Carlos; Miledi, Ricardo

    1998-01-01

    It has been postulated that, in the adult visual cortex, visual inputs modulate levels of mRNAs coding for neurotransmitter receptors in an activity-dependent manner. To investigate this possibility, we performed a monocular enucleation in adult rabbits and, 15 days later, collected their left and right visual cortices. Levels of mRNAs coding for voltage-activated sodium channels, and for receptors for kainate/α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA), N-methyl-d-aspartate (NMDA), γ-aminobutyric acid (GABA), and glycine were semiquantitatively estimated in the visual cortices ipsilateral and contralateral to the lesion by the Xenopus oocyte/voltage-clamp expression system. This technique also allowed us to study some of the pharmacological and physiological properties of the channels and receptors expressed in the oocytes. In cells injected with mRNA from left or right cortices of monocularly enucleated and control animals, the amplitudes of currents elicited by kainate or AMPA, which reflect the abundance of mRNAs coding for kainate and AMPA receptors, were similar. There was no difference in the sensitivity to kainate and in the voltage dependence of the kainate response. Responses mediated by NMDA, GABA, and glycine were unaffected by monocular enucleation. Sodium channel peak currents, activation, steady-state inactivation, and sensitivity to tetrodotoxin also remained unchanged after the enucleation. Our data show that mRNAs for major neurotransmitter receptors and ion channels in the adult rabbit visual cortex are not obviously modified by monocular deafferentiation. Thus, our results do not support the idea of a widespread dynamic modulation of mRNAs coding for receptors and ion channels by visual activity in the rabbit visual system. PMID:9501250

  1. Visualization and analysis of microtubule dynamics using dual color-coded display of plus-end labels.

    Directory of Open Access Journals (Sweden)

    Amy K Garrison

    Full Text Available Investigating spatial and temporal control of microtubule dynamics in live cells is critical to understanding cell morphogenesis in development and disease. Tracking fluorescently labeled plus-end-tracking proteins over time has become a widely used method to study microtubule assembly. Here, we report a complementary approach that uses only two images of these labels to visualize and analyze microtubule dynamics at any given time. Using a simple color-coding scheme, labeled plus-ends from two sequential images are pseudocolored with different colors and then merged to display color-coded ends. Based on object recognition algorithms, these colored ends can be identified and segregated into dynamic groups corresponding to four events, including growth, rescue, catastrophe, and pause. Further analysis yields not only their spatial distribution throughout the cell but also provides measurements such as growth rate and direction for each labeled end. We have validated the method by comparing our results with ground-truth data derived from manual analysis as well as with data obtained using the tracking method. In addition, we have confirmed color-coded representation of different dynamic events by analyzing their history and fate. Finally, we have demonstrated the use of the method to investigate microtubule assembly in cells and provided guidance in selecting optimal image acquisition conditions. Thus, this simple computer vision method offers a unique and quantitative approach to study spatial regulation of microtubule dynamics in cells.

  2. Comprehensive reconstruction and visualization of non-coding regulatory networks in human.

    Science.gov (United States)

    Bonnici, Vincenzo; Russo, Francesco; Bombieri, Nicola; Pulvirenti, Alfredo; Giugno, Rosalba

    2014-01-01

    Research attention has been powered to understand the functional roles of non-coding RNAs (ncRNAs). Many studies have demonstrated their deregulation in cancer and other human disorders. ncRNAs are also present in extracellular human body fluids such as serum and plasma, giving them a great potential as non-invasive biomarkers. However, non-coding RNAs have been relatively recently discovered and a comprehensive database including all of them is still missing. Reconstructing and visualizing the network of ncRNAs interactions are important steps to understand their regulatory mechanism in complex systems. This work presents ncRNA-DB, a NoSQL database that integrates ncRNAs data interactions from a large number of well established on-line repositories. The interactions involve RNA, DNA, proteins, and diseases. ncRNA-DB is available at http://ncrnadb.scienze.univr.it/ncrnadb/. It is equipped with three interfaces: web based, command-line, and a Cytoscape app called ncINetView. By accessing only one resource, users can search for ncRNAs and their interactions, build a network annotated with all known ncRNAs and associated diseases, and use all visual and mining features available in Cytoscape.

  3. Observational training in visual half-fields and the coding of movement sequences.

    Science.gov (United States)

    Ellenbuerger, Thomas; Boutin, Arnaud; Panzer, Stefan; Blandin, Yannick; Fischer, Lennart; Schorer, Joerg; Shea, Charles H

    2012-12-01

    An experiment was conducted to determine if gating information to different hemispheres during observational training facilitates the development of a movement representation. Participants were randomly assigned to one of three observation groups that differed in terms of the type of visual half-field presentation during observation (right visual half-field (RVF), left visual half-field (LVF), or in central position (CE)), and a control group (CG). On Day 1, visual stimuli indicating the pattern of movement to be produced were projected on the respective hemisphere. The task participants observed was a 1300 ms spatial-temporal pattern of elbow flexions and extensions. On Day 2, participants physically performed the task in an inter-manual transfer paradigm with a retention test, and two contralateral transfer tests; a mirror transfer test which required the same pattern of muscle activation and limb joint angles and a non-mirror transfer test which reinstated the visual-spatial pattern of the sequence. The results demonstrated that participants of the CE, RVF and the LVF groups showed superior retention and transfer performance compared to participants of the CG. Participants of the CE- and LVF-groups demonstrated an advantage when the visual-spatial coordinates were reinstated compared to the motor coordinates, while participants of the RVF-group did not promote specific transfer patterns. These results will be discussed in the context of hemisphere specialization.

  4. A LONE code for the sparse control of quantum systems

    Science.gov (United States)

    Ciaramella, G.; Borzì, A.

    2016-03-01

    In many applications with quantum spin systems, control functions with a sparse and pulse-shaped structure are often required. These controls can be obtained by solving quantum optimal control problems with L1-penalized cost functionals. In this paper, the MATLAB package LONE is presented aimed to solving L1-penalized optimal control problems governed by unitary-operator quantum spin models. This package implements a new strategy that includes a globalized semi-smooth Krylov-Newton scheme and a continuation procedure. Results of numerical experiments demonstrate the ability of the LONE code in computing accurate sparse optimal control solutions.

  5. Visual Control of Robots Using Range Images

    Directory of Open Access Journals (Sweden)

    Fernando Torres

    2010-08-01

    Full Text Available In the last years, 3D-vision systems based on the time-of-flight (ToF principle have gained more importance in order to obtain 3D information from the workspace. In this paper, an analysis of the use of 3D ToF cameras to guide a robot arm is performed. To do so, an adaptive method to simultaneous visual servo control and camera calibration is presented. Using this method a robot arm is guided by using range information obtained from a ToF camera. Furthermore, the self-calibration method obtains the adequate integration time to be used by the range camera in order to precisely determine the depth information.

  6. Internal Corrosion Control of Water Supply Systems Code of Practice

    Science.gov (United States)

    This Code of Practice is part of a series of publications by the IWA Specialist Group on Metals and Related Substances in Drinking Water. It complements the following IWA Specialist Group publications: 1. Best Practice Guide on the Control of Lead in Drinking Water 2. Best Prac...

  7. Internal Corrosion Control of Water Supply Systems Code of Practice

    Science.gov (United States)

    This Code of Practice is part of a series of publications by the IWA Specialist Group on Metals and Related Substances in Drinking Water. It complements the following IWA Specialist Group publications: 1. Best Practice Guide on the Control of Lead in Drinking Water 2. Best Prac...

  8. Beyond Control Panels: Direct Manipulation for Visual Analytics

    Energy Technology Data Exchange (ETDEWEB)

    Endert, Alexander; Bradel, Lauren; North, Chris

    2013-07-19

    Information Visualization strives to provide visual representations through which users can think about and gain insight into information. By leveraging the visual and cognitive systems of humans, complex relationships and phenomena occurring within datasets can be uncovered by exploring information visually. Interaction metaphors for such visualizations are designed to enable users direct control over the filters, queries, and other parameters controlling how the data is visually represented. Through the evolution of information visualization, more complex mathematical and data analytic models are being used to visualize relationships and patterns in data – creating the field of Visual Analytics. However, the expectations for how users interact with these visualizations has remained largely unchanged – focused primarily on the direct manipulation of parameters of the underlying mathematical models. In this article we present an opportunity to evolve the methodology for user interaction from the direct manipulation of parameters through visual control panels, to interactions designed specifically for visual analytic systems. Instead of focusing on traditional direct manipulation of mathematical parameters, the evolution of the field can be realized through direct manipulation within the visual representation – where users can not only gain insight, but also interact. This article describes future directions and research challenges that fundamentally change the meaning of direct manipulation with regards to visual analytics, advancing the Science of Interaction.

  9. Cholinergic control of visual categorisation in macaques

    Directory of Open Access Journals (Sweden)

    Nikolaos C. Aggelopoulos

    2011-11-01

    Full Text Available Acetylcholine (ACh is a neurotransmitter acting via muscarinic and nicotinic receptors that is implicated in several cognitive functions and impairments, such as Alzheimer’s disease. It is believed to especially affect the acquisition of new information, which is particularly important when behaviour needs to be adapted to new situations and to novel sensory events. Categorisation, the process of assigning stimuli to a category, is a cognitive function that also involves information acquisition. The role of ACh on categorisation has not been previously studied. We have examined the effects of scopolamine, an antagonist of muscarinic ACh receptors, on visual categorisation in macaque monkeys using familiar and novel stimuli. When the peripheral effects of scopolamine on the parasympathetic nervous system were controlled for, categorisation performance was disrupted following systemic injections of scopolamine. This impairment was observed only when the stimuli that needed to be categorised had not been seen before. In other words, the monkeys were not impaired by the central action of scopolamine in categorising a set of familiar stimuli (stimuli which they had categorised successfully in previous sessions. Categorisation performance also deteriorated as the stimulus became less salient by an increase in the level of visual noise. However, scopolamine did not cause additional performance disruptions for difficult categorisation judgements at lower coherence levels. Scopolamine, therefore, specifically affects the assignment of new exemplars to established cognitive categories, presumably by impairing the processing of novel information. Since we did not find an effect of scopolamine in the categorisation of familiar stimuli, scopolamine had no significant central action on other cognitive functions such as perception, attention, memory or executive control within the context of our categorisation task.

  10. Population coding in mouse visual cortex: response reliability and dissociability of stimulus tuning and noise correlation

    Directory of Open Access Journals (Sweden)

    Jorrit Steven Montijn

    2014-06-01

    Full Text Available The primary visual cortex is an excellent model system for investigating how neuronal populations encode information, because of well-documented relationships between stimulus characteristics and neuronal activation patterns. We used two-photon calcium imaging data to relate the performance of different methods for studying population coding (population vectors, template matching and Bayesian decoding algorithms to their underlying assumptions. We show that the variability of neuronal responses may hamper the decoding of population activity, and that a normalization to correct for this variability may be of critical importance for correct decoding of population activity. Second, by comparing noise correlations and stimulus tuning we find that these properties have dissociated anatomical correlates, even though noise correlations have been previously hypothesized to reflect common synaptic input. We hypothesize that noise correlations arise from large nonspecific increases in spiking activity acting on many weak synapses simultaneously, while neuronal stimulus response properties are dependent on more reliable connections. Finally, this paper provides practical guidelines for further research on population coding and shows that population coding cannot be approximated by a simple summation of inputs, but is heavily influenced by factors such as input reliability and noise correlation structure.

  11. Population coding in mouse visual cortex: response reliability and dissociability of stimulus tuning and noise correlation.

    Science.gov (United States)

    Montijn, Jorrit S; Vinck, Martin; Pennartz, Cyriel M A

    2014-01-01

    The primary visual cortex is an excellent model system for investigating how neuronal populations encode information, because of well-documented relationships between stimulus characteristics and neuronal activation patterns. We used two-photon calcium imaging data to relate the performance of different methods for studying population coding (population vectors, template matching, and Bayesian decoding algorithms) to their underlying assumptions. We show that the variability of neuronal responses may hamper the decoding of population activity, and that a normalization to correct for this variability may be of critical importance for correct decoding of population activity. Second, by comparing noise correlations and stimulus tuning we find that these properties have dissociated anatomical correlates, even though noise correlations have been previously hypothesized to reflect common synaptic input. We hypothesize that noise correlations arise from large non-specific increases in spiking activity acting on many weak synapses simultaneously, while neuronal stimulus response properties are dependent on more reliable connections. Finally, this paper provides practical guidelines for further research on population coding and shows that population coding cannot be approximated by a simple summation of inputs, but is heavily influenced by factors such as input reliability and noise correlation structure.

  12. Stimulus Specificity of Brain-Computer Interfaces Based on Code Modulation Visual Evoked Potentials.

    Directory of Open Access Journals (Sweden)

    Qingguo Wei

    Full Text Available A brain-computer interface (BCI based on code modulated visual evoked potentials (c-VEP is among the fastest BCIs that have ever been reported, but it has not yet been given a thorough study. In this study, a pseudorandom binary M sequence and its time lag sequences are utilized for modulation of different stimuli and template matching is adopted as the method for target recognition. Five experiments were devised to investigate the effect of stimulus specificity on target recognition and we made an effort to find the optimal stimulus parameters for size, color and proximity of the stimuli, length of modulation sequence and its lag between two adjacent stimuli. By changing the values of these parameters and measuring classification accuracy of the c-VEP BCI, an optimal value of each parameter can be attained. Experimental results of ten subjects showed that stimulus size of visual angle 3.8°, white, spatial proximity of visual angle 4.8° center to center apart, modulation sequence of length 63 bits and the lag of 4 bits between adjacent stimuli yield individually superior performance. These findings provide a basis for determining stimulus presentation of a high-performance c-VEP based BCI system.

  13. Computer codes for evaluation of control room habitability (HABIT)

    Energy Technology Data Exchange (ETDEWEB)

    Stage, S.A. [Pacific Northwest Lab., Richland, WA (United States)

    1996-06-01

    This report describes the Computer Codes for Evaluation of Control Room Habitability (HABIT). HABIT is a package of computer codes designed to be used for the evaluation of control room habitability in the event of an accidental release of toxic chemicals or radioactive materials. Given information about the design of a nuclear power plant, a scenario for the release of toxic chemicals or radionuclides, and information about the air flows and protection systems of the control room, HABIT can be used to estimate the chemical exposure or radiological dose to control room personnel. HABIT is an integrated package of several programs that previously needed to be run separately and required considerable user intervention. This report discusses the theoretical basis and physical assumptions made by each of the modules in HABIT and gives detailed information about the data entry windows. Sample runs are given for each of the modules. A brief section of programming notes is included. A set of computer disks will accompany this report if the report is ordered from the Energy Science and Technology Software Center. The disks contain the files needed to run HABIT on a personal computer running DOS. Source codes for the various HABIT routines are on the disks. Also included are input and output files for three demonstration runs.

  14. Secure quantum network coding for controlled repeater networks

    Science.gov (United States)

    Shang, Tao; Li, Jiao; Liu, Jian-wei

    2016-07-01

    To realize efficient quantum communication based on quantum repeater, we propose a secure quantum network coding scheme for controlled repeater networks, which adds a controller as a trusted party and is able to control the process of EPR-pair distribution. As the key operations of quantum repeater, local operations and quantum communication are designed to adopt quantum one-time pad to enhance the function of identity authentication instead of local operations and classical communication. Scheme analysis shows that the proposed scheme can defend against active attacks for quantum communication and realize long-distance quantum communication with minimal resource consumption.

  15. Model classification rate control algorithm for video coding

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A model classification rate control method for video coding is proposed. The macro-blocks are classified according to their prediction errors, and different parameters are used in the rate-quantization and distortion-quantization model.The different model parameters are calculated from the previous frame of the same type in the process of coding. These models are used to estimate the relations among rate, distortion and quantization of the current frame. Further steps,such as R-D optimization based quantization adjustment and smoothing of quantization of adjacent macroblocks, are used to improve the quality. The results of the experiments prove that the technique is effective and can be realized easily. The method presented in the paper can be a good way for MPEG and H. 264 rate control.

  16. Effect of visual stimulus using central and peripheral visual field on postural control of normal subjects.

    Science.gov (United States)

    Park, Du-Jin

    2016-06-01

    [Purpose] This study investigated the effects of visual stimulus using central and peripheral vision fields on postural control. [Subjects and Methods] The subjects consisted of 40 young adult volunteers (15 males, 25 females) who had been informed of the study purpose and procedure. The subjects were randomly divided into four groups of differing visual stimulus. Each group was given visual intervention in a standing position for 3 minutes. Postural control was evaluated before and after visual intervention. [Results] The results of the functional reach test and body sway test showed significant differences among the four groups. [Conclusion] The two-way peripheral vision-field group showed significantly more body sway after visual intervention than the other three groups. This finding may suggest two-way peripheral vision field is a more effective visual stimulus for training postural control and balance.

  17. [Visual attention and its control mechanisms].

    Science.gov (United States)

    Ogawa, Hirokazu

    2014-04-01

    Given the vast amount of visual information in visual scenes, the capacity of our brain to processes such scenes is severely limited. The core mechanism of selection is referred to as visual attention, and it has been the topic of intense investigation for over 25 years in experimental psychology and cognitive neuroscience. Visual attention is not a single, unitary mechanism, but consists of multiple subcomponents. Attention can be directed to various aspects of visual information, such as spatial location, features, or objects. Additionally, attention is guided by external factors such as the salience of stimuli, or whether we are able to move our attention volitionally. The purpose of this article is to review the status of these components of attentional guidance and how they interact with each other, with an emphasis on psychophysical studies.

  18. A Fuzzy-Based Approach for Sensing, Coding and Transmission Configuration of Visual Sensors in Smart City Applications.

    Science.gov (United States)

    Costa, Daniel G; Collotta, Mario; Pau, Giovanni; Duran-Faundez, Cristian

    2017-01-05

    The advance of technologies in several areas has allowed the development of smart city applications, which can improve the way of life in modern cities. When employing visual sensors in that scenario, still images and video streams may be retrieved from monitored areas, potentially providing valuable data for many applications. Actually, visual sensor networks may need to be highly dynamic, reflecting the changing of parameters in smart cities. In this context, characteristics of visual sensors and conditions of the monitored environment, as well as the status of other concurrent monitoring systems, may affect how visual sensors collect, encode and transmit information. This paper proposes a fuzzy-based approach to dynamically configure the way visual sensors will operate concerning sensing, coding and transmission patterns, exploiting different types of reference parameters. This innovative approach can be considered as the basis for multi-systems smart city applications based on visual monitoring, potentially bringing significant results for this research field.

  19. Coding of visual object features and feature conjunctions in the human brain.

    Directory of Open Access Journals (Sweden)

    Jasna Martinovic

    Full Text Available Object recognition is achieved through neural mechanisms reliant on the activity of distributed coordinated neural assemblies. In the initial steps of this process, an object's features are thought to be coded very rapidly in distinct neural assemblies. These features play different functional roles in the recognition process--while colour facilitates recognition, additional contours and edges delay it. Here, we selectively varied the amount and role of object features in an entry-level categorization paradigm and related them to the electrical activity of the human brain. We found that early synchronizations (approx. 100 ms increased quantitatively when more image features had to be coded, without reflecting their qualitative contribution to the recognition process. Later activity (approx. 200-400 ms was modulated by the representational role of object features. These findings demonstrate that although early synchronizations may be sufficient for relatively crude discrimination of objects in visual scenes, they cannot support entry-level categorization. This was subserved by later processes of object model selection, which utilized the representational value of object features such as colour or edges to select the appropriate model and achieve identification.

  20. Editing of EIA coded, numerically controlled, machine tool tapes

    Science.gov (United States)

    Weiner, J. M.

    1975-01-01

    Editing of numerically controlled (N/C) machine tool tapes (8-level paper tape) using an interactive graphic display processor is described. A rapid technique required for correcting production errors in N/C tapes was developed using the interactive text editor on the IMLAC PDS-ID graphic display system and two special programs resident on disk. The correction technique and special programs for processing N/C tapes coded to EIA specifications are discussed.

  1. Developments of Electromagnetic Particle Simulation Code for Magnetic Reconnection Researches in Open System PASMO and Visualization Library VISMO

    Science.gov (United States)

    Ohtani, H.; Horiuchi, R.; Nunami, M.; Usami, S.; Ohno, N.

    2014-10-01

    As the capabilities of computers are improved, the sizes of simulations become greater and greater. In this situation, we have some big issues. One of them is how to develop an efficient simulation code, and another is how to visualize the large data by the simulation. In order to investigate magnetic reconnection from the microscopic viewpoint, we develop a three-dimensional electromagnetic PIC code in an open system (PASMO). For performing the code on a distributed memory and multi-processor computer system with a distributed parallel algorithm, we decompose three-dimensionally the simulation domain, and introduce the charge conservation scheme to exclude the global calculation, such as Poisson solver with FFT. In the visualization of the simulation data, we develop an in-situ visualization library VISMO for the PIC simulation to carry out the visualization in tandem with the simulation on the same computers. The simulation code with VISMO generates image files instead of raw data. We will discuss the performance of the new PASMO and the simulation results visualized by VISMO on the magnetic reconnection. Supported by a Grant-in-Aid for Scientific Research from JSPS (Grant No. 23340182) and General Coordinated Research at NIFS (NIFS14KNSS046, NIFS13KNXN260 and NIFS13KNTS024).

  2. Joint Machine Learning and Game Theory for Rate Control in High Efficiency Video Coding.

    Science.gov (United States)

    Gao, Wei; Kwong, Sam; Jia, Yuheng

    2017-08-25

    In this paper, a joint machine learning and game theory modeling (MLGT) framework is proposed for inter frame coding tree unit (CTU) level bit allocation and rate control (RC) optimization in High Efficiency Video Coding (HEVC). First, a support vector machine (SVM) based multi-classification scheme is proposed to improve the prediction accuracy of CTU-level Rate-Distortion (R-D) model. The legacy "chicken-and-egg" dilemma in video coding is proposed to be overcome by the learning-based R-D model. Second, a mixed R-D model based cooperative bargaining game theory is proposed for bit allocation optimization, where the convexity of the mixed R-D model based utility function is proved, and Nash bargaining solution (NBS) is achieved by the proposed iterative solution search method. The minimum utility is adjusted by the reference coding distortion and frame-level Quantization parameter (QP) change. Lastly, intra frame QP and inter frame adaptive bit ratios are adjusted to make inter frames have more bit resources to maintain smooth quality and bit consumption in the bargaining game optimization. Experimental results demonstrate that the proposed MLGT based RC method can achieve much better R-D performances, quality smoothness, bit rate accuracy, buffer control results and subjective visual quality than the other state-of-the-art one-pass RC methods, and the achieved R-D performances are very close to the performance limits from the FixedQP method.

  3. A novel dynamic frame rate control algorithm for H.264 low-bit-rate video coding

    Institute of Scientific and Technical Information of China (English)

    Yang Jing; Fang Xiangzhong

    2007-01-01

    The goal of this paper is to improve human visual perceptual quality as well as coding efficiency of H.264 video at low bit rate conditions by adaptively adjusting the number of skipped frames. The encoding frames ale selected according to the motion activity of each frame and the motion accumulation of successive frames. The motion activity analysis is based on the statistics of motion vectors and with consideration of the characteristics of H. 264 coding standard. A prediction model of motion accumulation is proposed to reduce complex computation of motion estimation. The dynamic encoding frame rate control algorithm is applied to both the frame level and the GOB (Group of Macroblocks) level. Simulation is done to compare the performance of JM76 with the proposed frame level scheme and GOB level scheme.

  4. Interactive tag cloud visualization of software version control repositories

    CSIR Research Space (South Africa)

    Greene, GJ

    2015-09-01

    Full Text Available Visualization of Software: Version Control Repositories Gillian J. Greene and Bernd Fischer Abstract: Version control repositories contain a wealth of implicit information that can be used to answer many questions about a project’s development process...

  5. A Novel Container ISO Code Localization Using an Object Clustering Method with Opencv and Visual Studio Application

    Directory of Open Access Journals (Sweden)

    Ronesh Sharma

    2013-06-01

    Full Text Available An automatic container code recognition system is of a great importance to the logistic supply chain management. Techniques have been proposed and implemented for the ISO container code region identification and recognition, however those systems have limitations on the type of container images with illumination factor and marks present on the container due to handling in the mass environmental condition. Moreover the research is not limited for differentiating between different formats of code and color of code characters. In this paper firstly an object clustering method is proposed to localize each line of the container code region. Secondly, the localizing algorithm is implemented with opencv and visual studio to perform localization and then recognition. Thus for real time application, the implemented system has added advantage of being easily integrated with other web application to increase the efficiency of the supply chain management. The experimental results and the application demonstrate the effectiveness of the proposed system for practical use.

  6. CONTROL SCHEMES FOR CMAC NEURAL NETWORK-BASED VISUAL SERVOING

    Institute of Scientific and Technical Information of China (English)

    Wang Huaming; Xi Wenming; Zhu Jianying

    2003-01-01

    In IBVS (image based visual servoing), the error signal in image space should be transformed into the control signal in the input space quickly. To avoid the iterative adjustment and complicated inverse solution of image Jacobian, CMAC (cerebellar model articulation controller) neural network is inserted into visual servo control loop to implement the nonlinear mapping. Two control schemes are used. Simulation results on two schemes are provided, which show a better tracking precision and stability can be achieved using scheme 2.

  7. Scanning tunneling microscope data acquisition and control in visual basic

    Science.gov (United States)

    Porter, T. L.

    1993-12-01

    A general purpose data acquisition and control system for scanning tunneling microscopy (STM) using Visual Basic is presented. This Windows hosted Visual Basic environment is highly desirable for use in STM image manipulation, storage, and printing, but in its standard form is not suitable for most data acquisition and display applications. Many of the inherent limitations in the Visual Basic language have been overcome by the use of direct calls to the Windows Application Program Interface. In this paper, we describe a general Visual Basic STM user interface and control system, and the extensions to the language using the Windows API needed to implement this system.

  8. Visual Features Involving Motion Seen from Airport Control Towers

    Science.gov (United States)

    Ellis, Stephen R.; Liston, Dorion

    2010-01-01

    Visual motion cues are used by tower controllers to support both visual and anticipated separation. Some of these cues are tabulated as part of the overall set of visual features used in towers to separate aircraft. An initial analyses of one motion cue, landing deceleration, is provided as a basis for evaluating how controllers detect and use it for spacing aircraft on or near the surface. Understanding cues like it will help determine if they can be safely used in a remote/virtual tower in which their presentation may be visually degraded.

  9. Network Coding-Based Communications via the Controlled Quantum Teleportation

    Directory of Open Access Journals (Sweden)

    Ying Guo

    2013-02-01

    Full Text Available Inspired by the structure of the network coding over the butterfly network, a framework of quantum network coding scheme is investigated, which transmits two unknown quantum states crossly over the butterfly quantum system with the multi-photon non-maximally entangled GHZ states. In this scheme, it contains certain number of entanglement-qubit source nodes that teleport unknown quantum states to other nodes on the small-scale network where each intermediate node can pass on its received quantum states to others via superdense coding. In order to transmit the unknown states in a deterministic way, the controlled quantum teleportation is adopted on the intermediate node. It makes legal nodes more convenient than any other previous teleportation schemes to transmit unknown quantum states to unknown participants in applications. It shows that the intrinsic efficiency of transmissions approaches 100% in principle. This scheme is secure based on the securely-shared quantum channels between all nodes and the quantum mechanical impossibility of local unitary transformations between non-maximally entangled GHZ states. Moreover, the generalized scheme is proposed for transmitting two multipartite entangled states.

  10. Quantum control using genetic algorithms in quantum communication: superdense coding

    Science.gov (United States)

    Domínguez-Serna, Francisco; Rojas, Fernando

    2015-06-01

    We present a physical example model of how Quantum Control with genetic algorithms is applied to implement the quantum superdense code protocol. We studied a model consisting of two quantum dots with an electron with spin, including spin-orbit interaction. The electron and the spin get hybridized with the site acquiring two degrees of freedom, spin and charge. The system has tunneling and site energies as time dependent control parameters that are optimized by means of genetic algorithms to prepare a hybrid Bell-like state used as a transmission channel. This state is transformed to obtain any state of the four Bell basis as required by superdense protocol to transmit two bits of classical information. The control process protocol is equivalent to implement one of the quantum gates in the charge subsystem. Fidelities larger than 99.5% are achieved for the hybrid entangled state preparation and the superdense operations.

  11. A RAMP CODE FOR FINE-GRAINED ACCESS CONTROL

    Directory of Open Access Journals (Sweden)

    Kannan Karthik

    2013-02-01

    Full Text Available Threshold ramp secret sharing schemes are designed so that (i certain subsets of shares have no information about the secret, (ii some subsets have partial information about the secret and (iii some subsets have complete information to recover the secret. However most of the ramp schemes in present literature do not control the leakage of information in partial access sets, due to which the information acquired by these sets is devoid of structure and not useful for fine-grained access control. Through a non-perfect secret sharing scheme called MIX-SPLIT, an encoding methodology for controlling the leakage in partial access sets is proposed and this is used for fine-grained access to binary strings. The ramp code generated using MIX-SPLIT requires a much smaller share size of O(n, as compared to Shamir's ramp adaptation which incurs a share size of atleast O(n2 for the same multi-access structure. The proposed ramp code is finally applied towards the protection and fine-grained access of industrial design drawings.

  12. A hybrid Jacobian control for uncalibrated robot visual servoing

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qizhi; GE Xinsheng; TEO Chee-Leong; LIM Siak-Piang

    2005-01-01

    This paper focuses on the visual servo control of an uncalibrated robotic arm with an eye-in-hand camera. Without a prior knowledge of the kinematics of the robotic arm or camera calibration, the proposed hybrid Jacobian controller can track a moving object using visual feedback and joint-space velocity feedback. The proposed hybrid control method is a combination of the uncalibrated visual servoing and approximate Jacobian feedback control. First, the Jacobian matrix from joint-space to image-space is estimated by recursive leastsquares (RLS) algorithm, and then the approximate Jacobian feedback controller is designed by using visual feedback and joint-space velocity feedback. The performances of the proposed control methods are illustrated by computer simulations.

  13. Proprioceptive versus Visual Control in Autistic Children.

    Science.gov (United States)

    Masterton, B. A.; Biederman, G. B.

    1983-01-01

    The autistic children's presumed preference for proximal over distal sensory input was studied by requiring that "autistic," retarded, and "normal" children (7-15 years old) adapt to lateral displacement of the visual field. Only autistic Ss demonstrated transfer of adaptation to the nonadapted hand, indicating reliance on proprioception rather…

  14. Word meaning in the ventral visual path: a perceptual to conceptual gradient of semantic coding.

    Science.gov (United States)

    Borghesani, Valentina; Pedregosa, Fabian; Buiatti, Marco; Amadon, Alexis; Eger, Evelyn; Piazza, Manuela

    2016-12-01

    The meaning of words referring to concrete items is thought of as a multidimensional representation that includes both perceptual (e.g., average size, prototypical color) and conceptual (e.g., taxonomic class) dimensions. Are these different dimensions coded in different brain regions? In healthy human subjects, we tested the presence of a mapping between the implied real object size (a perceptual dimension) and the taxonomic categories at different levels of specificity (conceptual dimensions) of a series of words, and the patterns of brain activity recorded with functional magnetic resonance imaging in six areas along the ventral occipito-temporal cortical path. Combining multivariate pattern classification and representational similarity analysis, we found that the real object size implied by a word appears to be primarily encoded in early visual regions, while the taxonomic category and sub-categorical cluster in more anterior temporal regions. This anteroposterior gradient of information content indicates that different areas along the ventral stream encode complementary dimensions of the semantic space.

  15. Visualizing Concurrency Control Algorithms for Real-Time Database Systems

    Directory of Open Access Journals (Sweden)

    Olusegun Folorunso

    2008-11-01

    Full Text Available This paper describes an approach to visualizing concurrency control (CC algorithms for real-time database systems (RTDBs. This approach is based on the principle of software visualization, which has been applied in related fields. The Model-View-controller (MVC architecture is used to alleviate the black box syndrome associated with the study of algorithm behaviour for RTDBs Concurrency Controls. We propose a Visualization "exploratory" tool that assists the RTDBS designer in understanding the actual behaviour of the concurrency control algorithms of choice and also in evaluating the performance quality of the algorithm. We demonstrate the feasibility of our approach using an optimistic concurrency control model as our case study. The developed tool substantiates the earlier simulation-based performance studies by exposing spikes at some points when visualized dynamically that are not observed using usual static graphs. Eventually this tool helps solve the problem of contradictory assumptions of CC in RTDBs.

  16. Fine-grained temporal coding of visually-similar categories in the ventral visual pathway and prefrontal cortex

    Directory of Open Access Journals (Sweden)

    Yang eXu

    2013-10-01

    Full Text Available Humans are remarkably proficient at categorizing visually-similar objects. To better understand the cortical basis of this categorization process, we used magnetoencephalography (MEG to record neural activity while participants learned--with feedback--to discriminate two highly-similar, novel visual categories. We hypothesized that although prefrontal regions would mediate early category learning, this role would diminish with increasing category familiarity and that regions within the ventral visual pathway would come to play a more prominent role in encoding category-relevant information as learning progressed. Early in learning we observed some degree of categorical discriminability and predictability in both the prefrontal cortex and the ventral visual pathway. Predictability improved significantly above chance in the ventral visual pathway over the course of learning with the left inferiortemporal and fusiform gyri showing the greatest improvement in predictability between 150-250msec (M200 during category learning. In contrast, there was no comparable increase in discriminability in prefrontal cortex with the only significant post-learning effect being a decrease in predictability in inferior frontal gyrus between 250-350msec (M300. Thus, the ventral visual pathway appears to encode learned visual categories over the long term. At the same time these results add to our understanding of the cortical origins of previously-reported signature temporal components associated with perceptual learning.

  17. C code generation applied to nonlinear model predictive control for an artificial pancreas

    DEFF Research Database (Denmark)

    Boiroux, Dimitri; Jørgensen, John Bagterp

    2017-01-01

    This paper presents a method to generate C code from MATLAB code applied to a nonlinear model predictive control (NMPC) algorithm. The C code generation uses the MATLAB Coder Toolbox. It can drastically reduce the time required for development compared to a manual porting of code from MATLAB to C...

  18. Patient DF's visual brain in action: Visual feedforward control in visual form agnosia.

    Science.gov (United States)

    Whitwell, Robert L; Milner, A David; Cavina-Pratesi, Cristiana; Barat, Masihullah; Goodale, Melvyn A

    2015-05-01

    Patient DF, who developed visual form agnosia following ventral-stream damage, is unable to discriminate the width of objects, performing at chance, for example, when asked to open her thumb and forefinger a matching amount. Remarkably, however, DF adjusts her hand aperture to accommodate the width of objects when reaching out to pick them up (grip scaling). While this spared ability to grasp objects is presumed to be mediated by visuomotor modules in her relatively intact dorsal stream, it is possible that it may rely abnormally on online visual or haptic feedback. We report here that DF's grip scaling remained intact when her vision was completely suppressed during grasp movements, and it still dissociated sharply from her poor perceptual estimates of target size. We then tested whether providing trial-by-trial haptic feedback after making such perceptual estimates might improve DF's performance, but found that they remained significantly impaired. In a final experiment, we re-examined whether DF's grip scaling depends on receiving veridical haptic feedback during grasping. In one condition, the haptic feedback was identical to the visual targets. In a second condition, the haptic feedback was of a constant intermediate width while the visual target varied trial by trial. Despite this incongruent feedback, DF still scaled her grip aperture to the visual widths of the target blocks, showing only normal adaptation to the false haptically-experienced width. Taken together, these results strengthen the view that DF's spared grasping relies on a normal mode of dorsal-stream functioning, based chiefly on visual feedforward processing. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Control Code for Bearingless Switched-Reluctance Motor

    Science.gov (United States)

    Morrison, Carlos R.

    2007-01-01

    A computer program has been devised for controlling a machine that is an integral combination of magnetic bearings and a switched-reluctance motor. The motor contains an eight-pole stator and a hybrid rotor, which has both (1) a circular lamination stack for levitation and (2) a six-pole lamination stack for rotation. The program computes drive and levitation currents for the stator windings with real-time feedback control. During normal operation, two of the four pairs of opposing stator poles (each pair at right angles to the other pair) levitate the rotor. The remaining two pairs of stator poles exert torque on the six-pole rotor lamination stack to produce rotation. This version is executable in a control-loop time of 40 s on a Pentium (or equivalent) processor that operates at a clock speed of 400 MHz. The program can be expanded, by addition of logic blocks, to enable control of position along additional axes. The code enables adjustment of operational parameters (e.g., motor speed and stiffness, and damping parameters of magnetic bearings) through computer keyboard key presses.

  20. A mouse model of visual perceptual learning reveals alterations in neuronal coding and dendritic spine density in the visual cortex

    Directory of Open Access Journals (Sweden)

    Yan eWang

    2016-03-01

    Full Text Available Visual perceptual learning (VPL can improve spatial vision in normally sighted and visually impaired individuals. Although previous studies of humans and large animals have explored the neural basis of VPL, elucidation of the underlying cellular and molecular mechanisms remains a challenge. Owing to the advantages of molecular genetic and optogenetic manipulations, the mouse is a promising model for providing a mechanistic understanding of VPL. Here, we thoroughly evaluated the effects and properties of VPL on spatial vision in C57BL/6J mice using a two-alternative, forced-choice visual water task. Briefly, the mice underwent prolonged training at near the individual threshold of contrast or spatial frequency (SF for pattern discrimination or visual detection for 35 consecutive days. Following training, the contrast-threshold trained mice showed an 87% improvement in contrast sensitivity (CS and a 55% gain in visual acuity (VA. Similarly, the SF-threshold trained mice exhibited comparable and long-lasting improvements in VA and significant gains in CS over a wide range of SFs. Furthermore, learning largely transferred across eyes and stimulus orientations. Interestingly, learning could transfer from a pattern discrimination task to a visual detection task, but not vice versa. We validated that this VPL fully restored VA in adult amblyopic mice and old mice. Taken together, these data indicate that mice, as a species, exhibit reliable VPL. Intrinsic signal optical imaging revealed that mice with perceptual training had higher cut-off SFs in primary visual cortex (V1 than those without perceptual training. Moreover, perceptual training induced an increase in the dendritic spine density in layer 2/3 pyramidal neurons of V1. These results indicated functional and structural alterations in V1 during VPL. Overall, our VPL mouse model will provide a platform for investigating the neurobiological basis of VPL.

  1. Predictive Control for Visual Servo Stabilization of Nonholonomic Mobile Robots

    Institute of Scientific and Technical Information of China (English)

    CAO Zheng-Cai; YIN Long-Jie; FU Yi-Li; LIU Tian-Long

    2013-01-01

    Visual servo stabilization of nonholonomic mobile robots has gained extensive attention.However,currently,the solution of the problem does not consider both the visibility constraints and the actuator limitations,so the designed controller is difficult to realize satisfactory performance in practical application.In this paper,a predictive controller for the visual servo stabilization of a mobile robot is presented.Firstly,a kinematic predictive stabilization controller utilized to generate the command of velocity is introduced.Then,in order to make the actual velocity of the mobile robot asymptotically approach to the desired one,a dynamic predictive controller is designed.The proposed predictive controller can deal with the constraints easily.Finally,several simulations are performed,and the results illustrate that the proposed control scheme is effective to solve the visual servo stabilization problem.

  2. Reflections on Codes of Conduct: Asymmetries, Vulnerabilities, and Institutional Controls

    Science.gov (United States)

    Bray, Nathaniel J.; Braxton, John M.

    2012-01-01

    Codes of conduct can and should fulfill a critical role in higher education. Codes help overcome some of the challenges inherent in a system predicated on high levels of autonomy and on self-regulation. Codes not only are important indicators of critical topics that are deemed worthy of explicit protection or expectations for behavior; they may…

  3. UNICOS CPC6: Automated Code Generation for Process Control Applications

    CERN Document Server

    Fernandez Adiego, B; Prieto Barreiro, I

    2011-01-01

    The Continuous Process Control package (CPC) is one of the components of the CERN Unified Industrial Control System framework (UNICOS) [1]. As a part of this framework, UNICOS-CPC provides a well defined library of device types, amethodology and a set of tools to design and implement industrial control applications. The new CPC version uses the software factory UNICOS Application Builder (UAB) [2] to develop CPC applications. The CPC component is composed of several platform oriented plugins PLCs and SCADA) describing the structure and the format of the generated code. It uses a resource package where both, the library of device types and the generated file syntax, are defined. The UAB core is the generic part of this software, it discovers and calls dynamically the different plug-ins and provides the required common services. In this paper the UNICOS CPC6 package is introduced. It is composed of several plug-ins: the Instance generator and the Logic generator for both, Siemens and Schneider PLCs, the SCADA g...

  4. Closed-Loop Learning of Visual Control Policies

    CERN Document Server

    Jodogne, S R; 10.1613/jair.2110

    2011-01-01

    In this paper we present a general, flexible framework for learning mappings from images to actions by interacting with the environment. The basic idea is to introduce a feature-based image classifier in front of a reinforcement learning algorithm. The classifier partitions the visual space according to the presence or absence of few highly informative local descriptors that are incrementally selected in a sequence of attempts to remove perceptual aliasing. We also address the problem of fighting overfitting in such a greedy algorithm. Finally, we show how high-level visual features can be generated when the power of local descriptors is insufficient for completely disambiguating the aliased states. This is done by building a hierarchy of composite features that consist of recursive spatial combinations of visual features. We demonstrate the efficacy of our algorithms by solving three visual navigation tasks and a visual version of the classical Car on the Hill control problem.

  5. Visual control of steering in the box jellyfish Tripedalia cystophora

    DEFF Research Database (Denmark)

    Petie, Ronald; Garm, Anders; Nilsson, Dan-Eric

    2011-01-01

    Box jellyfish carry an elaborate visual system consisting of 24 eyes, which they use for driving a number of behaviours. However, it is not known how visual input controls the swimming behaviour. In this study we exposed the Caribbean box jellyfish Tripedalia cystophora to simple visual stimuli...... their bell in such a way that, if not tethered, they would turn and swim away from the dark area. We conclude that the visual system of T. cystophora has a predictable effect on swimming behaviour....... to the darkening of one quadrant of the equatorial visual world by (1) increasing pulse frequency, (2) creating an asymmetry in the structure that constricts the outflow opening of the bell, the velarium, and (3) delaying contraction at one of the four sides of the bell. This causes the animals to orient...

  6. The Deceptively Simple N170 Reflects Network Information Processing Mechanisms Involving Visual Feature Coding and Transfer Across Hemispheres

    Science.gov (United States)

    Ince, Robin A. A.; Jaworska, Katarzyna; Gross, Joachim; Panzeri, Stefano; van Rijsbergen, Nicola J.; Rousselet, Guillaume A.; Schyns, Philippe G.

    2016-01-01

    A key to understanding visual cognition is to determine “where”, “when”, and “how” brain responses reflect the processing of the specific visual features that modulate categorization behavior—the “what”. The N170 is the earliest Event-Related Potential (ERP) that preferentially responds to faces. Here, we demonstrate that a paradigmatic shift is necessary to interpret the N170 as the product of an information processing network that dynamically codes and transfers face features across hemispheres, rather than as a local stimulus-driven event. Reverse-correlation methods coupled with information-theoretic analyses revealed that visibility of the eyes influences face detection behavior. The N170 initially reflects coding of the behaviorally relevant eye contralateral to the sensor, followed by a causal communication of the other eye from the other hemisphere. These findings demonstrate that the deceptively simple N170 ERP hides a complex network information processing mechanism involving initial coding and subsequent cross-hemispheric transfer of visual features. PMID:27550865

  7. LUMPED: a Visual Basic code of lumped-parameter models for mean residence time analyses of groundwater systems

    Science.gov (United States)

    Ozyurt, N. N.; Bayari, C. S.

    2003-02-01

    A Microsoft ® Visual Basic 6.0 (Microsoft Corporation, 1987-1998) code of 15 lumped-parameter models is presented for the analysis of mean residence time in aquifers. Groundwater flow systems obeying plug and exponential flow models and their combinations of parallel or serial connection can be simulated by these steady-state models which may include complications such as bypass flow and dead volume. Each model accepts tritium, krypton-85, chlorofluorocarbons (CFC-11, CFC-12 and CFC-113) and sulfur hexafluoride (SF 6) as environmental tracer. Retardation of gas tracers in the unsaturated zone and their degradation in the flow system may also be accounted for. The executable code has been tested to run under Windows 95 or higher operating systems. The results of comparisons between other comparable codes are discussed and the limitations are indicated.

  8. Use of fluorescent proteins and color-coded imaging to visualize cancer cells with different genetic properties.

    Science.gov (United States)

    Hoffman, Robert M

    2016-03-01

    Fluorescent proteins are very bright and available in spectrally-distinct colors, enable the imaging of color-coded cancer cells growing in vivo and therefore the distinction of cancer cells with different genetic properties. Non-invasive and intravital imaging of cancer cells with fluorescent proteins allows the visualization of distinct genetic variants of cancer cells down to the cellular level in vivo. Cancer cells with increased or decreased ability to metastasize can be distinguished in vivo. Gene exchange in vivo which enables low metastatic cancer cells to convert to high metastatic can be color-coded imaged in vivo. Cancer stem-like and non-stem cells can be distinguished in vivo by color-coded imaging. These properties also demonstrate the vast superiority of imaging cancer cells in vivo with fluorescent proteins over photon counting of luciferase-labeled cancer cells.

  9. Emergence of visual saliency from natural scenes via context-mediated probability distributions coding.

    Directory of Open Access Journals (Sweden)

    Jinhua Xu

    Full Text Available Visual saliency is the perceptual quality that makes some items in visual scenes stand out from their immediate contexts. Visual saliency plays important roles in natural vision in that saliency can direct eye movements, deploy attention, and facilitate tasks like object detection and scene understanding. A central unsolved issue is: What features should be encoded in the early visual cortex for detecting salient features in natural scenes? To explore this important issue, we propose a hypothesis that visual saliency is based on efficient encoding of the probability distributions (PDs of visual variables in specific contexts in natural scenes, referred to as context-mediated PDs in natural scenes. In this concept, computational units in the model of the early visual system do not act as feature detectors but rather as estimators of the context-mediated PDs of a full range of visual variables in natural scenes, which directly give rise to a measure of visual saliency of any input stimulus. To test this hypothesis, we developed a model of the context-mediated PDs in natural scenes using a modified algorithm for independent component analysis (ICA and derived a measure of visual saliency based on these PDs estimated from a set of natural scenes. We demonstrated that visual saliency based on the context-mediated PDs in natural scenes effectively predicts human gaze in free-viewing of both static and dynamic natural scenes. This study suggests that the computation based on the context-mediated PDs of visual variables in natural scenes may underlie the neural mechanism in the early visual cortex for detecting salient features in natural scenes.

  10. Visualization of Instrumental Verification Information Details (VIVID) : code development, description, and usage.

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Christopher John; Bainbridge, Bruce L.; Potter, Donald L.; Blottner, Frederick G.; Black, Amalia Rebecca

    2005-03-01

    The formulation, implementation and usage of a numerical solution verification code is described. This code uses the Richardson extrapolation procedure to estimate the order of accuracy and error of a computational program solution. It evaluates multiple solutions performed in numerical grid convergence studies to verify a numerical algorithm implementation. Analyses are performed on both structured and unstructured grid codes. Finite volume and finite element discretization programs are examined. Two and three-dimensional solutions are evaluated. Steady state and transient solution analysis capabilities are present in the verification code. Multiple input data bases are accepted. Benchmark options are included to allow for minimal solution validation capability as well as verification.

  11. Robust Control for High-Speed Visual Servoing Applications

    DEFF Research Database (Denmark)

    Ellekilde, Lars-Peter; Favrholdt, Peter; Paulin, Mads;

    2007-01-01

    This paper presents a new control scheme for visual servoing applications. The approach employs quadratic optimization, and explicitly handles both joint position, velocity and acceleration limits. Contrary to existing techniques, our method does not rely on large safety margins and slow task...... the correctness and efficiency of our approach in a number of visual servoing applications, and compare it to a range of previously proposed techniques....

  12. Raman-based distributed temperature sensor using simplex code and gain controlled EDFA

    Science.gov (United States)

    Bassan, F. R.; Penze, R. S.; Leonardi, A. A.; Fracarolli, J. P. V.; Floridia, C.; Rosolem, J. B.; Fruett, F.

    2015-09-01

    In this work we present a comparison between simplex coded and optical amplified simplex coded Raman based Distributed Temperature Sensing (DTS). An increase in performance is demonstrated using erbium doped fiber amplifier (EDFA) with proper gain control scheme that allows a DTS operates with simplex code. Using 63-bit simplex code and gain controlled EDFA we demonstrated the temperature resolution and dynamic range improvement in 16 °C @ 10 km and 4 dB, respectively.

  13. Codes on Graphs: Observability, Controllability and Local Reducibility

    OpenAIRE

    Forney Jr, G. David; Gluesing-Luerssen, Heide

    2012-01-01

    This paper investigates properties of realizations of linear or group codes on general graphs that lead to local reducibility. Trimness and properness are dual properties of constraint codes. A linear or group realization with a constraint code that is not both trim and proper is locally reducible. A linear or group realization on a finite cycle-free graph is minimal if and only if every local constraint code is trim and proper. A realization is called observable if there is a one-to-one corr...

  14. The use of visual cues for vehicle control and navigation

    Science.gov (United States)

    Hart, Sandra G.; Battiste, Vernol

    1991-01-01

    At least three levels of control are required to operate most vehicles: (1) inner-loop control to counteract the momentary effects of disturbances on vehicle position; (2) intermittent maneuvers to avoid obstacles, and (3) outer-loop control to maintain a planned route. Operators monitor dynamic optical relationships in their immediate surroundings to estimate momentary changes in forward, lateral, and vertical position, rates of change in speed and direction of motion, and distance from obstacles. The process of searching the external scene to find landmarks (for navigation) is intermittent and deliberate, while monitoring and responding to subtle changes in the visual scene (for vehicle control) is relatively continuous and 'automatic'. However, since operators may perform both tasks simultaneously, the dynamic optical cues available for a vehicle control task may be determined by the operator's direction of gaze for wayfinding. An attempt to relate the visual processes involved in vehicle control and wayfinding is presented. The frames of reference and information used by different operators (e.g., automobile drivers, airline pilots, and helicopter pilots) are reviewed with particular emphasis on the special problems encountered by helicopter pilots flying nap of the earth (NOE). The goal of this overview is to describe the context within which different vehicle control tasks are performed and to suggest ways in which the use of visual cues for geographical orientation might influence visually guided control activities.

  15. Extraction and Visualization of Call Dependencies for Large C/C++ Code Bases : A Comparative Study

    NARCIS (Netherlands)

    Telea, Alexandru; Hoogendorp, Hessel; Ersoy, Ozan; Reniers, Dennie; Lanza, M; Storey, M; Muller, H

    2009-01-01

    Investigating program dependencies such as function calls is challenging for very large systems. We present here an integrated pipeline for extraction and visualization of call-and-hierarchy graphs for C/C++ programs. We present several adaptions and enhancements of a recent visualization method for

  16. Impaired Letter-String Processing in Developmental Dyslexia: What Visual-to-Phonology Code Mapping Disorder?

    Science.gov (United States)

    Valdois, Sylviane; Lassus-Sangosse, Delphine; Lobier, Muriel

    2012-01-01

    Poor parallel letter-string processing in developmental dyslexia was taken as evidence of poor visual attention (VA) span, that is, a limitation of visual attentional resources that affects multi-character processing. However, the use of letter stimuli in oral report tasks was challenged on its capacity to highlight a VA span disorder. In…

  17. Dense codes at high speeds: varying stimulus properties to improve visual speller performance

    NARCIS (Netherlands)

    Geuze, J.; Farquhar, J.D.R.; Desain, P.W.M.

    2012-01-01

    This paper investigates the effect of varying different stimulus properties on performance of the visual speller. Each of the different stimulus properties has been tested in previous literature and has a known effect on visual speller performance. This paper investigates whether a combination of th

  18. Visual discrimination among patients with depression and schizophrenia and healthy individuals using semiquantitative color-coded fast spin-echo T1-weighted magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, Makoto; Kudo, Kohsuke; Narumi, Shinsuke [Iwate Medical University, Advanced Medical Research Center, Morioka (Japan); Shibata, Eri; Ohtsuka, Kotaro; Endoh, Jin; Sakai, Akio [Iwate Medical University, Department of Neuropsychiatry, Morioka (Japan)

    2010-02-15

    Fast spin-echo (FSE) T1-weighted (T1W) magnetic resonance imaging (MRI) at 3T, which is sensitive to neuromelanin-related contrast, can quantitatively detect signal alterations in the locus ceruleus (LC) and the substantia nigra pars compacta (SNc) of depressive and schizophrenic patients; however, its qualitative diagnostic performance remains unknown. We investigated whether visual interpretation of semiquantitative color maps can be used for discriminating between depressive and schizophrenic patients and healthy individuals. We retrospectively examined 23 patients with major depression, 23 patients with schizophrenia, and 23 age-matched healthy controls by using a FSE-T1W MRI technique. Semiquantitative color maps of sections through the LC and SNc were visually interpreted by nine raters using a continuous confidence rating scale for receiver operating characteristic (ROC) analysis. The area under the ROC curve (Az), which reflects the performance in differentiating between depressive patients and controls, was 0.88, and the sensitivity and specificity at the maximum likelihood were 76% and 83%, respectively. In contrast, the Az value, sensitivity, and specificity values between schizophrenics and controls and between depressives and schizophrenics were 0.66 and 0.69, 42% and 48%, and 82% and 84%, respectively. Semiquantitative, color-coded FSE-T1W MRI at 3T can be used for visually differentiating depressive patients from healthy individuals with a substantially high likelihood, but this technique cannot be applied to distinguish schizophrenic patients from the other two groups. (orig.)

  19. Visual world perception modeling and control of cooperative mobile robots

    Science.gov (United States)

    Shirkhodaie, Amir

    2003-10-01

    There has been a great interest in the recent years in visual coordination and target tracking for mobile robots cooperating in unstructured environments. This paper describes visual servo control techniques suitable for intelligent task planning of cooperative robots operating in unstructured environment. In this paper, we have considered a team of semi-autonomous robots controlled by a remote supervisory control system. We have presented an algorithm for visual position tracking of individual cooperative robots within their working environment. Initially, we present a technique suitable for visual servoing of a robot toward its landmark targets. Secondly, we present an image-processing technique that utilizes images from a remote surveillance camera for localization of the robots within the operational environment. In this algorithm, the surveillance camera can be either stationary or mobile. The supervisor control system keeps tracks of relative locations of individual robots and utilizes relative coordinate information of the robots to plan their cooperative activities. We presented some results of this research effort that illustrates effectiveness of the proposed algorithms for cooperative robotic systems visual team working and target tracking.

  20. Advanced Error-Control Coding Methods Enhance Reliability of Transmission and Storage Data Systems

    Directory of Open Access Journals (Sweden)

    K. Vlcek

    2003-04-01

    Full Text Available Iterative coding systems are currently being proposed and acceptedfor many future systems as next generation wireless transmission andstorage systems. The text gives an overview of the state of the art initerative decoded FEC (Forward Error-Correction error-control systems.Such systems can typically achieve capacity to within a fraction of adB at unprecedented low complexities. Using a single code requires verylong code words, and consequently very complex coding system. One wayaround the problem of achieving very low error probabilities is turbocoding (TC application. A general model of concatenated coding systemis shown - an algorithm of turbo codes is given in this paper.

  1. A case-control study of visual acuity in onychocryptosis.

    LENUS (Irish Health Repository)

    Hogan, Aisling M

    2012-02-01

    BACKGROUND: There are many theories surrounding the etiology of ingrown toenails (IGTN). Few factors have been formally assessed, but it is widely accepted that a poor nail cutting technique has a causative role. AIM: To investigate the hypothesis that decreased visual acuity may lead to inadequate nail cutting and the formation of IGTN. METHODS: A prospective case-control study was performed. Near and distance visual acuity were tested on a population with IGTN (n = 19) and compared with that of an age- and sex-matched control cohort (n = 24) who underwent epidermal cyst excision in the same tertiary referral center. Comparisons of visual acuity were made between groups by Mann-Whitney U-test. Differences were taken to be significant if P < 0.05. Institutional Review Board approval was sought and granted. RESULTS: No significant difference in visual acuity (near or distance) was demonstrated between patients with IGTN and the control group (P = 0.33). CONCLUSION: Visual acuity does not appear to play a significant role in the development of IGTN.

  2. A Character Segmentation Proposal for High-Speed Visual Monitoring of Expiration Codes on Beverage Cans

    Directory of Open Access Journals (Sweden)

    José C. Rodríguez-Rodríguez

    2016-04-01

    Full Text Available Expiration date labels are ubiquitous in the food industry. With the passage of time, almost any food becomes unhealthy, even when well preserved. The expiration date is estimated based on the type and manufacture/packaging time of that particular food unit. This date is then printed on the container so it is available to the end user at the time of consumption. MONICOD (MONItoring of CODes; an industrial validator of expiration codes; allows the expiration code printed on a drink can to be read. This verification occurs immediately after printing. MONICOD faces difficulties due to the high printing rate (35 cans per second and problematic lighting caused by the metallic surface on which the code is printed. This article describes a solution that allows MONICOD to extract shapes and presents quantitative results for the speed and quality.

  3. A Character Segmentation Proposal for High-Speed Visual Monitoring of Expiration Codes on Beverage Cans.

    Science.gov (United States)

    Rodríguez-Rodríguez, José C; Quesada-Arencibia, Alexis; Moreno-Díaz, Roberto; García, Carmelo R

    2016-04-13

    Expiration date labels are ubiquitous in the food industry. With the passage of time, almost any food becomes unhealthy, even when well preserved. The expiration date is estimated based on the type and manufacture/packaging time of that particular food unit. This date is then printed on the container so it is available to the end user at the time of consumption. MONICOD (MONItoring of CODes); an industrial validator of expiration codes; allows the expiration code printed on a drink can to be read. This verification occurs immediately after printing. MONICOD faces difficulties due to the high printing rate (35 cans per second) and problematic lighting caused by the metallic surface on which the code is printed. This article describes a solution that allows MONICOD to extract shapes and presents quantitative results for the speed and quality.

  4. Visual-Motor Control in Baseball Batting

    Directory of Open Access Journals (Sweden)

    Rob Gray

    2011-05-01

    Full Text Available With margins for error of a few milliseconds and fractions of an inch it is not surprising that hitting a baseball is considered to be one of the most difficult acts in all of sports. We have been investigating this challenging behavior using a virtual baseball batting setup in which simulations of an approaching ball, pitcher, and field are combined with real-time recording of bat and limb movements. I will present evidence that baseball batting involves variable pre-programmed control in which the swing direction and movement time (MT are set prior to the initiation of the action but can take different values from swing-to-swing. This programming process utilizes both advance information (pitch history and count and optical information picked-up very early in the ball's flight (ball time to contact TTC and rotation direction. The pre-programmed value of MT is used to determine a critical value of TTC for swing initiation. Finally, because a baseball swing is an action that is occasionally interrupted online (i.e., a “check swing”, I will discuss experiments that examine when this pre-programmed action can be stopped and the sources of optical information that trigger stopping.

  5. Visual Flight Control of a Quadrotor Using Bioinspired Motion Detector

    Directory of Open Access Journals (Sweden)

    Lei Zhang

    2012-01-01

    Full Text Available Motion detection in the fly is extremely fast with low computational requirements. Inspired from the fly's vision system, we focus on a real-time flight control on a miniquadrotor with fast visual feedback. In this work, an elaborated elementary motion detector (EMD is utilized to detect local optical flow. Combined with novel receptive field templates, the yaw rate of the quadrotor is estimated through a lookup table established with this bioinspired visual sensor. A closed-loop control system with the feedback of yaw rate estimated by EMD is designed. With the motion of the other degrees of freedom stabilized by a camera tracking system, the yaw-rate of the quadrotor during hovering is controlled based on EMD feedback under real-world scenario. The control performance of the proposed approach is compared with that of conventional approach. The experimental results demonstrate the effectiveness of utilizing EMD for quadrotor control.

  6. Architectural Visualization of C/C++ Source Code for Program Comprehension

    Energy Technology Data Exchange (ETDEWEB)

    Panas, T; Epperly, T W; Quinlan, D; Saebjornsen, A; Vuduc, R

    2006-09-01

    Structural and behavioral visualization of large-scale legacy systems to aid program comprehension is still a major challenge. The challenge is even greater when applications are implemented in flexible and expressive languages such as C and C++. In this paper, we consider visualization of static and dynamic aspects of large-scale scientific C/C++ applications. For our investigation, we reuse and integrate specialized analysis and visualization tools. Furthermore, we present a novel layout algorithm that permits a compressive architectural view of a large-scale software system. Our layout is unique in that it allows traditional program visualizations, i.e., graph structures, to be seen in relation to the application's file structure.

  7. Visualization

    OpenAIRE

    Balon, Andreja

    1990-01-01

    The present thesis entails the field of visualization which is divided into visualization along traditional lines and visualization in computer science. As the psychological aspect of image is of vital importance for visualization, it is shortly described in the beginning. Visualization in computer science is divided into three main fields: scientific visualization, program visualization and visual programming. An explanation and examples of approach to applications are given for each field....

  8. Shape of magnifiers affects controllability in children with visual impairment.

    Science.gov (United States)

    Liebrand-Schurink, Joyce; Boonstra, F Nienke; van Rens, Ger H M B; Cillessen, Antonius H N; Meulenbroek, Ruud G J; Cox, Ralf F A

    2016-12-01

    This study aimed to examine the controllability of cylinder-shaped and dome-shaped magnifiers in young children with visual impairment. This study investigates goal-directed arm movements in low-vision aid use (stand and dome magnifier-like object) in a group of young children with visual impairment (n = 56) compared to a group of children with normal sight (n = 66). Children with visual impairment and children with normal sight aged 4-8 years executed two types of movements (cyclic and discrete) in two orientations (vertical or horizontal) over two distances (10 cm and 20 cm) with two objects resembling the size and shape of regularly prescribed stand and dome magnifiers. The visually impaired children performed slower movements than the normally sighted children. In both groups, the accuracy and speed of the reciprocal aiming movements improved significantly with age. Surprisingly, in both groups, the performance with the dome-shaped object was significantly faster (in the 10 cm condition and 20 cm condition with discrete movements) and more accurate (in the 20 cm condition) than with the stand-shaped object. From a controllability perspective, this study suggests that it is better to prescribe dome-shaped than cylinder-shaped magnifiers to young children with visual impairment. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  9. Follow the leader: visual control of speed in pedestrian following.

    Science.gov (United States)

    Rio, Kevin W; Rhea, Christopher K; Warren, William H

    2014-02-07

    When people walk together in groups or crowds they must coordinate their walking speed and direction with their neighbors. This paper investigates how a pedestrian visually controls speed when following a leader on a straight path (one-dimensional following). To model the behavioral dynamics of following, participants in Experiment 1 walked behind a confederate who randomly increased or decreased his walking speed. The data were used to test six models of speed control that used the leader's speed, distance, or combinations of both to regulate the follower's acceleration. To test the optical information used to control speed, participants in Experiment 2 walked behind a virtual moving pole, whose visual angle and binocular disparity were independently manipulated. The results indicate the followers match the speed of the leader, and do so using a visual control law that primarily nulls the leader's optical expansion (change in visual angle), with little influence of change in disparity. This finding has direct applications to understanding the coordination among neighbors in human crowds.

  10. CoCo trial: Color-coded blood pressure Control, a randomized controlled study

    Science.gov (United States)

    Chmiel, Corinne; Senn, Oliver; Rosemann, Thomas; Del Prete, Valerio; Steurer-Stey, Claudia

    2014-01-01

    Background Inadequate blood pressure (BP) control is a frequent challenge in general practice. The objective of this study was to determine whether a color-coded BP booklet using a traffic light scheme (red, >180 mmHg systolic BP and/or >110 mmHg diastolic BP; yellow, >140–180 mmHg systolic BP or >90–110 mmHg diastolic BP; green, ≤140 mmHg systolic BP and ≤90 mmHg diastolic BP) improves BP control and adherence with home BP measurement. Methods In this two-group, randomized controlled trial, general practitioners recruited adult patients with a BP >140 mmHg systolic and/or >90 mmHg diastolic. Patients in the control group received a standard BP booklet and the intervention group used a color-coded booklet for daily home BP measurement. The main outcomes were changes in BP, BP control (treatment goal <140/90 mmHg), and adherence with home BP measurement after 6 months. Results One hundred and twenty-one of 137 included patients qualified for analysis. After 6 months, a significant decrease in systolic and diastolic BP was achieved in both groups, with no significant difference between the groups (16.1/7.9 mmHg in the intervention group versus 13.1/8.6 mmHg in the control group, P=0.3/0.7). BP control (treatment target <140/90 mmHg) was achieved significantly more often in the intervention group (43% versus 25%; P=0.037; number needed to treat of 5). Adherence with home BP measurement overall was high, with a trend in favor of the intervention group (98.6% versus 96.2%; P=0.1) Conclusion Color-coded BP self-monitoring significantly improved BP control (number needed to treat of 5, meaning that every fifth patient utilizing color-coded self-monitoring achieved better BP control after 6 months), but no significant between-group difference was observed in BP change. A markedly higher percentage of patients achieved BP values in the normal range. This simple, inexpensive approach of color-coded BP self-monitoring is user-friendly and applicable in primary care

  11. Navigation-specific neural coding in the visual system of Drosophila.

    Science.gov (United States)

    Dewar, Alex D M; Wystrach, Antoine; Graham, Paul; Philippides, Andrew

    2015-10-01

    Drosophila melanogaster are a good system in which to understand the minimal requirements for widespread visually guided behaviours such as navigation, due to their small brains (adults possess only 100,000 neurons) and the availability of neurogenetic techniques which allow the identification of task-specific cell types. Recently published data describe the receptive fields for two classes of visually responsive neurons (R2 and R3/R4d ring neurons in the central complex) that are essential for visual tasks such as orientation memory for salient objects and simple pattern discriminations. What is interesting is that these cells have very large receptive fields and are very small in number, suggesting that each sub-population of cells might be a bottleneck in the processing of visual information for a specific behaviour, as each subset of cells effectively condenses information from approximately 3000 visual receptors in the eye, to fewer than 50 neurons in total. It has recently been shown how R1 ring neurons, which receive input from the same areas as the R2 and R3/R4d cells, are necessary for place learning in Drosophila. However, how R1 neurons enable place learning is unknown. By examining the information provided by different populations of hypothetical visual neurons in simulations of experimental arenas, we show that neurons with ring neuron-like receptive fields are sufficient for defining a location visually. In this way we provide a link between the type of information conveyed by ring neurons and the behaviour they support.

  12. Comparison of Mars Science Laboratory Reaction Control System Jet Computations With Flow Visualization and Velocimetry

    Science.gov (United States)

    Bathel, Brett F.; Danehy, Paul M.; Johansen, Craig T.; Ashcraft, Scott W.; Novak, Luke A.

    2013-01-01

    Numerical predictions of the Mars Science Laboratory reaction control system jets interacting with a Mach 10 hypersonic flow are compared to experimental nitric oxide planar laser-induced fluorescence data. The steady Reynolds Averaged Navier Stokes equations using the Baldwin-Barth one-equation turbulence model were solved using the OVERFLOW code. The experimental fluorescence data used for comparison consists of qualitative two-dimensional visualization images, qualitative reconstructed three-dimensional flow structures, and quantitative two-dimensional distributions of streamwise velocity. Through modeling of the fluorescence signal equation, computational flow images were produced and directly compared to the qualitative fluorescence data.

  13. CONTROLLING STUDENT RESPONSES DURING VISUAL PRESENTATIONS--STUDIES IN TELEVISED INSTRUCTION, THE ROLE OF VISUALS IN VERBAL LEARNING, REPORT 2.

    Science.gov (United States)

    GROPPER, GEORGE L.

    THIS IS A REPORT OF TWO STUDIES IN WHICH PRINCIPLES OF PROGRAMED INSTRUCTION WERE ADAPTED FOR VISUAL PRESENTATIONS. SCIENTIFIC DEMONSTRATIONS WERE PREPARED WITH A VISUAL PROGRAM AND A VERBAL PROGRAM ON--(1) ARCHIMEDES' LAW AND (2) FORCE AND PRESSURE. RESULTS SUGGESTED THAT RESPONSES ARE MORE READILY BROUGHT UNDER THE CONTROL OF VISUAL PRESENTATION…

  14. An Adaptive Video Coding Control Scheme for Real-Time MPEG Applications

    Directory of Open Access Journals (Sweden)

    Hsia Shih-Chang

    2003-01-01

    Full Text Available This paper proposes a new rate control scheme to increase the coding efficiency for MPEG systems. Instead of using a static group of picture (GOP structure, we present an adaptive GOP structure that uses more P- and B-frame coding, while the temporal correlation among the video frames maintains high. When there is a scene change, we immediately insert intramode coding to reduce the prediction error. Moreover, an enhanced prediction frame is used to improve the coding quality in the adaptive GOP. This rate control algorithm can both achieve better coding efficiency and solve the scene change problem. Even if the coding bit rate is over the predefined level, this coding scheme does not require re-encoding for real-time systems. Simulations demonstrate that our proposed algorithm can achieve better quality than TM5, and satisfactory reliability for detecting scene changes.

  15. A Neurophysiologically Plausible Population Code Model for Feature Integration Explains Visual Crowding

    NARCIS (Netherlands)

    Berg, Ronald van den; Roerdink, Jos B.T.M.; Cornelissen, Frans W.

    2010-01-01

    An object in the peripheral visual field is more difficult to recognize when surrounded by other objects. This phenomenon is called "crowding". Crowding places a fundamental constraint on human vision that limits performance on numerous tasks. It has been suggested that crowding results from spatial

  16. Population coding in mouse visual cortex : Response reliability and dissociability of stimulus tuning and noise correlation

    NARCIS (Netherlands)

    Montijn, J.S.; Vinck, M.; Pennartz, C.M.A.

    2014-01-01

    The primary visual cortex is an excellent model system for investigating how neuronal populations encode information, because of well-documented relationships between stimulus characteristics and neuronal activation patterns. We used two-photon calcium imaging data to relate the performance of

  17. Population coding of visual space: comparison of spatial representations in the dorsal and ventral pathways

    Directory of Open Access Journals (Sweden)

    Anne B Sereno

    2011-02-01

    Full Text Available Although the representation of space is as fundamental to visual processing as the representation of shape, it has received relatively little attention from neurophysiological investigations. In this study we characterize representations of space within visual cortex, and examine how they differ in a first direct comparison between dorsal and ventral subdivisions of the visual pathways. Neural activities were recorded in anterior inferotemporal cortex (AIT and lateral intraparietal cortex (LIP of awake behaving monkeys, structures associated with the ventral and dorsal visual pathways respectively, as a stimulus was presented at different locations within the visual field. In spatially selective cells, we find greater modulation of cell responses in LIP with changes in stimulus position. Further, using a novel population-based statistical approach (namely, multidimensional scaling, we recover the spatial map implicit within activities of neural populations, allowing us to quantitatively compare the geometry of neural space with physical space. We show that a population of spatially selective LIP neurons, despite having large receptive fields, is able to almost perfectly reconstruct stimulus locations within a low-dimensional representation. In contrast, a population of AIT neurons, despite each cell being spatially selective, provide less accurate low-dimensional reconstructions of stimulus locations. They produce instead only a topologically (categorically correct rendition of space, which nevertheless might be critical for object and scene recognition. Furthermore, we found that the spatial representation recovered from population activity shows greater translation invariance in LIP than in AIT. We suggest that LIP spatial representations may be dimensionally isomorphic with 3D physical space, while in AIT spatial representations may reflect a more categorical representation of space (e.g., next to or above.

  18. The Role of Architectural and Learning Constraints in Neural Network Models: A Case Study on Visual Space Coding.

    Science.gov (United States)

    Testolin, Alberto; De Filippo De Grazia, Michele; Zorzi, Marco

    2017-01-01

    The recent "deep learning revolution" in artificial neural networks had strong impact and widespread deployment for engineering applications, but the use of deep learning for neurocomputational modeling has been so far limited. In this article we argue that unsupervised deep learning represents an important step forward for improving neurocomputational models of perception and cognition, because it emphasizes the role of generative learning as opposed to discriminative (supervised) learning. As a case study, we present a series of simulations investigating the emergence of neural coding of visual space for sensorimotor transformations. We compare different network architectures commonly used as building blocks for unsupervised deep learning by systematically testing the type of receptive fields and gain modulation developed by the hidden neurons. In particular, we compare Restricted Boltzmann Machines (RBMs), which are stochastic, generative networks with bidirectional connections trained using contrastive divergence, with autoencoders, which are deterministic networks trained using error backpropagation. For both learning architectures we also explore the role of sparse coding, which has been identified as a fundamental principle of neural computation. The unsupervised models are then compared with supervised, feed-forward networks that learn an explicit mapping between different spatial reference frames. Our simulations show that both architectural and learning constraints strongly influenced the emergent coding of visual space in terms of distribution of tuning functions at the level of single neurons. Unsupervised models, and particularly RBMs, were found to more closely adhere to neurophysiological data from single-cell recordings in the primate parietal cortex. These results provide new insights into how basic properties of artificial neural networks might be relevant for modeling neural information processing in biological systems.

  19. The Role of Architectural and Learning Constraints in Neural Network Models: A Case Study on Visual Space Coding

    Science.gov (United States)

    Testolin, Alberto; De Filippo De Grazia, Michele; Zorzi, Marco

    2017-01-01

    The recent “deep learning revolution” in artificial neural networks had strong impact and widespread deployment for engineering applications, but the use of deep learning for neurocomputational modeling has been so far limited. In this article we argue that unsupervised deep learning represents an important step forward for improving neurocomputational models of perception and cognition, because it emphasizes the role of generative learning as opposed to discriminative (supervised) learning. As a case study, we present a series of simulations investigating the emergence of neural coding of visual space for sensorimotor transformations. We compare different network architectures commonly used as building blocks for unsupervised deep learning by systematically testing the type of receptive fields and gain modulation developed by the hidden neurons. In particular, we compare Restricted Boltzmann Machines (RBMs), which are stochastic, generative networks with bidirectional connections trained using contrastive divergence, with autoencoders, which are deterministic networks trained using error backpropagation. For both learning architectures we also explore the role of sparse coding, which has been identified as a fundamental principle of neural computation. The unsupervised models are then compared with supervised, feed-forward networks that learn an explicit mapping between different spatial reference frames. Our simulations show that both architectural and learning constraints strongly influenced the emergent coding of visual space in terms of distribution of tuning functions at the level of single neurons. Unsupervised models, and particularly RBMs, were found to more closely adhere to neurophysiological data from single-cell recordings in the primate parietal cortex. These results provide new insights into how basic properties of artificial neural networks might be relevant for modeling neural information processing in biological systems. PMID:28377709

  20. Robust Visual Control of Parallel Robots under Uncertain Camera Orientation

    Directory of Open Access Journals (Sweden)

    Miguel A. Trujano

    2012-10-01

    Full Text Available This work presents a stability analysis and experimental assessment of a visual control algorithm applied to a redundant planar parallel robot under uncertainty in relation to camera orientation. The key feature of the analysis is a strict Lyapunov function that allows the conclusion of asymptotic stability without invoking the Barbashin-Krassovsky-LaSalle invariance theorem. The controller does not rely on velocity measurements and has a structure similar to a classic Proportional Derivative control algorithm. Experiments in a laboratory prototype show that uncertainty in camera orientation does not significantly degrade closed-loop performance.

  1. A Coded Aperture Compressive Imaging Array and Its Visual Detection and Tracking Algorithms for Surveillance Systems

    Directory of Open Access Journals (Sweden)

    Hanxiao Wu

    2012-10-01

    Full Text Available In this paper, we propose an application of a compressive imaging system to the problem of wide-area video surveillance systems. A parallel coded aperture compressive imaging system is proposed to reduce the needed high resolution coded mask requirements and facilitate the storage of the projection matrix. Random Gaussian, Toeplitz and binary phase coded masks are utilized to obtain the compressive sensing images. The corresponding motion targets detection and tracking algorithms directly using the compressive sampling images are developed. A mixture of Gaussian distribution is applied in the compressive image space to model the background image and for foreground detection. For each motion target in the compressive sampling domain, a compressive feature dictionary spanned by target templates and noises templates is sparsely represented. An l1 optimization algorithm is used to solve the sparse coefficient of templates. Experimental results demonstrate that low dimensional compressed imaging representation is sufficient to determine spatial motion targets. Compared with the random Gaussian and Toeplitz phase mask, motion detection algorithms using a random binary phase mask can yield better detection results. However using random Gaussian and Toeplitz phase mask can achieve high resolution reconstructed image. Our tracking algorithm can achieve a real time speed that is up to 10 times faster than that of the l1 tracker without any optimization.

  2. Divided multimodal attention sensory trace and context coding strategies in spatially congruent auditory and visual presentation.

    Science.gov (United States)

    Kristjánsson, Tómas; Thorvaldsson, Tómas Páll; Kristjánsson, Arni

    2014-01-01

    Previous research involving both unimodal and multimodal studies suggests that single-response change detection is a capacity-free process while a discriminatory up or down identification is capacity-limited. The trace/context model assumes that this reflects different memory strategies rather than inherent differences between identification and detection. To perform such tasks, one of two strategies is used, a sensory trace or a context coding strategy, and if one is blocked, people will automatically use the other. A drawback to most preceding studies is that stimuli are presented at separate locations, creating the possibility of a spatial confound, which invites alternative interpretations of the results. We describe a series of experiments, investigating divided multimodal attention, without the spatial confound. The results challenge the trace/context model. Our critical experiment involved a gap before a change in volume and brightness, which according to the trace/context model blocks the sensory trace strategy, simultaneously with a roaming pedestal, which should block the context coding strategy. The results clearly show that people can use strategies other than sensory trace and context coding in the tasks and conditions of these experiments, necessitating changes to the trace/context model.

  3. Layered Multicast Encryption of Motion JPEG2000 Code Streams for Flexible Access Control

    Science.gov (United States)

    Nakachi, Takayuki; Toyoshima, Kan; Tonomura, Yoshihide; Fujii, Tatsuya

    In this paper, we propose a layered multicast encryption scheme that provides flexible access control to motion JPEG2000 code streams. JPEG2000 generates layered code streams and offers flexible scalability in characteristics such as resolution and SNR. The layered multicast encryption proposal allows a sender to multicast the encrypted JPEG2000 code streams such that only designated groups of users can decrypt the layered code streams. While keeping the layering functionality, the proposed method offers useful properties such as 1) video quality control using only one private key, 2) guaranteed security, and 3) low computational complexity comparable to conventional non-layered encryption. Simulation results show the usefulness of the proposed method.

  4. Evaluation of the Knowledge Level of High School Students in the João Pessoa City with Visual Impairment About Unified Chemistry and Mathematics Braille Code

    Directory of Open Access Journals (Sweden)

    João Batista M. de Resende Filho

    2013-06-01

    Full Text Available The Braille Code is very important in the educational process of students with visual impairment, because this writing system allows which the students know the systematic and organized writing knowledge. These students need to know the symbols and the use’s standards of them, so they can write, read and understand the contents. The Unified Chemistry and Mathematics Braille Code are fundamentally important for these students to understand the texts about these themes. This study aimed to evaluation of the knowledge level of High School students with visual impairment in the João Pessoa city about Unified Chemistry and Mathematics Braille Code. The students showed a relatively good knowledge of symbols and rules of the Unified Mathematics Braille Code, presenting, in the most cases, difficulties in recognizing unusual symbols. The student’s main difficulties were related to Unified Chemistry Braille Code, because they did not know many symbols and writing rules, presenting a low knowledge level.

  5. Spatiotopic coding of BOLD signal in human visual cortex depends on spatial attention.

    Directory of Open Access Journals (Sweden)

    Sofia Crespi

    Full Text Available The neural substrate of the phenomenological experience of a stable visual world remains obscure. One possible mechanism would be to construct spatiotopic neural maps where the response is selective to the position of the stimulus in external space, rather than to retinal eccentricities, but evidence for these maps has been inconsistent. Here we show, with fMRI, that when human subjects perform concomitantly a demanding attentive task on stimuli displayed at the fovea, BOLD responses evoked by moving stimuli irrelevant to the task were mostly tuned in retinotopic coordinates. However, under more unconstrained conditions, where subjects could attend easily to the motion stimuli, BOLD responses were tuned not in retinal but in external coordinates (spatiotopic selectivity in many visual areas, including MT, MST, LO and V6, agreeing with our previous fMRI study. These results indicate that spatial attention may play an important role in mediating spatiotopic selectivity.

  6. Holistic neural coding of Chinese character forms in bilateral ventral visual system.

    Science.gov (United States)

    Mo, Ce; Yu, Mengxia; Seger, Carol; Mo, Lei

    2015-02-01

    How are Chinese characters recognized and represented in the brain of skilled readers? Functional MRI fast adaptation technique was used to address this question. We found that neural adaptation effects were limited to identical characters in bilateral ventral visual system while no activation reduction was observed for partially overlapping characters regardless of the spatial location of the shared sub-character components, suggesting highly selective neuronal tuning to whole characters. The consistent neural profile across the entire ventral visual cortex indicates that Chinese characters are represented as mutually distinctive wholes rather than combinations of sub-character components, which presents a salient contrast to the left-lateralized, simple-to-complex neural representations of alphabetic words. Our findings thus revealed the cultural modulation effect on both local neuronal activity patterns and functional anatomical regions associated with written symbol recognition. Moreover, the cross-language discrepancy in written symbol recognition mechanism might stem from the language-specific early-stage learning experience.

  7. OPR1000 Control Rod Drop Accident Simulation using the SPACE Code

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Chang Keun; Ha, Sang Jun; Moon, Chan Kook [Korea Hydro and Nuclear Power, Daejeon (Korea, Republic of)

    2012-05-15

    The Korea nuclear industry has developed a best estimated two-phase three-filed thermal-hydraulic analysis code, SPACE (Safety and Performance Analysis Code for Nuclear Power Plants), for safety analysis and design of a PWR (Pressurized Water Reactor). As the first phase, the demo version of the SPACE code was released in March 2010. The code has been verified and improved according to the Validation and Verification (V and V) matrix prepared for the SPACE code as the second phase of the development. In this study, a Control Rod Drop accident has been simulated using the SPACE code as one aspect of the V and V work. The results from this test were compared with tests of the RETRAN and CESEC codes

  8. An autonomous miniature wheeled robot based on visual feedback control

    Institute of Scientific and Technical Information of China (English)

    CHEN Haichu

    2007-01-01

    Using two micro-motors,a novel omni-direction miniature wheeled robot is designed on the basis of the bi-corner driving principle.The robot takes advantage of the Bluetooth technology to wirelessly transmit data at a short distance.Its position and omni-direction motion are precise.A Charge Coupled Device(CCD)camera is used for measuring and for visual navigation.A control system is developed.The precision of the position is 0.5 mm,the resolution is about 0.05 mm,and the maximum velocity is about 52 mm/s.The visual navigation and control system allow the robot to navigate and track the target and to accomplish autonomous locomotion.

  9. Visual and non-visual control of landing movements in humans

    Science.gov (United States)

    Santello, Marco; McDonagh, Martin J N; Challis, John H

    2001-01-01

    The role of vision in controlling leg muscle activation in landing from a drop was investigated. Subjects (n = 8) performed 10 drops from four heights (0.2, 0.4, 0.6 and 0.8 m) with and without vision. Drop height was maintained constant throughout each block of trials to allow adaptation. The aim of the study was to assess the extent to which proprioceptive and vestibular information could substitute for the lack of vision in adapting landing movements to different heights. At the final stages of the movement, subjects experienced similar peak centre of body mass (CM) displacements and joint rotations, regardless of the availability of vision. This implies that subjects were able to adapt the control of landing to different heights. The amplitude and timing of electromyographic signals from the leg muscles scaled to drop height in a similar fashion with and without vision. However, variables measured throughout the execution of the movement indicated important differences. Without vision, landings were characterised by 10 % larger ground reaction forces, 10 % smaller knee joint rotations, different time lags between peak joint rotations, and more variable ground reaction forces and times to peak CM displacement. We conclude that non-visual sensory information (a) could not fully compensate for the lack of continuous visual feedback and (b) this non-visual information was used to reorganise the motor output. These results suggest that vision is important for the very accurate timing of muscle activity onset and the kinematics of landing. PMID:11711583

  10. LUMPED Unsteady: a Visual Basic ® code of unsteady-state lumped-parameter models for mean residence time analyses of groundwater systems

    Science.gov (United States)

    Ozyurt, N. Nur; Bayari, C. Serdar

    2005-04-01

    A Microsoft ® Visual Basic 6.0 (Microsoft Corporation, 1987-1998) code of 9 lumped-parameter models of unsteady flow is presented for the analysis of mean residence time in aquifers. Groundwater flow systems obeying plug and well-mixed flow models and their combinations in parallel or serial connection can be simulated by the code. Models can use tritium, tritiugenic He-3, oxygen-18, deuterium, krypton-85, chlorofluorocarbons (CFC-11, CFC-12 and CFC-113) and sulfur hexafluoride (SF 6) as the environmental tracers. The executable code runs under all 32-bit Windows operating systems. Details of the code are explained and its limitations are indicated.

  11. The impact of concurrent visual feedback on coding of on-line and pre-planned movement sequences.

    Science.gov (United States)

    Leinen, Peter; Shea, Charles H; Panzer, Stefan

    2015-02-01

    The purpose of this study was to determine the extent to which participants could effectively switch from on-line (OL) to pre-planned (PP) control (or vice versa) depending on previous practice conditions and whether concurrent visual feedback was available during transfer testing. The task was to reproduce a 2000 ms spatial-temporal pattern of a sequence of elbow flexions and extensions. Participants were randomly assigned to one of two practice conditions termed OL or PP. In the OL condition the criterion waveform and the cursor were provided during movement production while this information was withheld during movement production for the PP condition. A retention test and two effector transfer tests were administered to half of the participants in each acquisition conditions under OL conditions and the other half under PP conditions. The mirror effector transfer test required the same pattern of muscle activation and limb joint angles as required during acquisition. The non-mirror transfer test required movements to the same visual-spatial locations as experienced during acquisition. The results indicated that when visual information was available during the transfer tests performers could switch from PP to OL. When visual information was withdrawn, they shifted from the OL to the PP-control mode. This finding suggests that performers adopt a mode of control consistent with the feedback conditions provided during testing.

  12. Control of humanoid robot via motion-onset visual evoked potentials.

    Science.gov (United States)

    Li, Wei; Li, Mengfan; Zhao, Jing

    2014-01-01

    This paper investigates controlling humanoid robot behavior via motion-onset specific N200 potentials. In this study, N200 potentials are induced by moving a blue bar through robot images intuitively representing robot behaviors to be controlled with mind. We present the individual impact of each subject on N200 potentials and discuss how to deal with individuality to obtain a high accuracy. The study results document the off-line average accuracy of 93% for hitting targets across over five subjects, so we use this major component of the motion-onset visual evoked potential (mVEP) to code people's mental activities and to perform two types of on-line operation tasks: navigating a humanoid robot in an office environment with an obstacle and picking-up an object. We discuss the factors that affect the on-line control success rate and the total time for completing an on-line operation task.

  13. First responder tracking and visualization for command and control toolkit

    Science.gov (United States)

    Woodley, Robert; Petrov, Plamen; Meisinger, Roger

    2010-04-01

    In order for First Responder Command and Control personnel to visualize incidents at urban building locations, DHS sponsored a small business research program to develop a tool to visualize 3D building interiors and movement of First Responders on site. 21st Century Systems, Inc. (21CSI), has developed a toolkit called Hierarchical Grid Referenced Normalized Display (HiGRND). HiGRND utilizes three components to provide a full spectrum of visualization tools to the First Responder. First, HiGRND visualizes the structure in 3D. Utilities in the 3D environment allow the user to switch between views (2D floor plans, 3D spatial, evacuation routes, etc.) and manually edit fast changing environments. HiGRND accepts CAD drawings and 3D digital objects and renders these in the 3D space. Second, HiGRND has a First Responder tracker that uses the transponder signals from First Responders to locate them in the virtual space. We use the movements of the First Responder to map the interior of structures. Finally, HiGRND can turn 2D blueprints into 3D objects. The 3D extruder extracts walls, symbols, and text from scanned blueprints to create the 3D mesh of the building. HiGRND increases the situational awareness of First Responders and allows them to make better, faster decisions in critical urban situations.

  14. Integration and visualization of non-coding RNA and protein interaction networks

    DEFF Research Database (Denmark)

    Junge, Alexander; Refsgaard, Jan Christian; Garde, Christian

    Non-coding RNAs (ncRNAs) fulfill a diverse set of biological functions relying on interactions with other molecular entities. The advent of new experimental and computational approaches makes it possible to study ncRNAs and their associations on an unprecedented scale. We present RAIN (RNA Associ......) co-occurrences found by text mining Medline abstracts. Each resource was assigned a reliability score by assessing its agreement with a gold standard set of microRNA-target interactions. RAIN is available at: http://rth.dk/resources/rain...

  15. CoCo trial: Color-coded blood pressure Control, a randomized controlled study

    Directory of Open Access Journals (Sweden)

    Chmiel C

    2014-10-01

    Full Text Available Corinne Chmiel, Oliver Senn, Thomas Rosemann, Valerio Del Prete, Claudia Steurer-Stey Institute of General Practice and Health Services Research, University of Zurich, Zurich, Switzerland Background: Inadequate blood pressure (BP control is a frequent challenge in general practice. The objective of this study was to determine whether a color-coded BP booklet using a traffic light scheme (red, >180 mmHg systolic BP and/or >110 mmHg diastolic BP; yellow, >140–180 mmHg systolic BP or >90–110 mmHg diastolic BP; green, ≤140 mmHg systolic BP and ≤90 mmHg diastolic BP improves BP control and adherence with home BP measurement.Methods: In this two-group, randomized controlled trial, general practitioners recruited adult patients with a BP >140 mmHg systolic and/or >90 mmHg diastolic. Patients in the control group received a standard BP booklet and the intervention group used a color-coded booklet for daily home BP measurement. The main outcomes were changes in BP, BP control (treatment goal <140/90 mmHg, and adherence with home BP measurement after 6 months.Results: One hundred and twenty-one of 137 included patients qualified for analysis. After 6 months, a significant decrease in systolic and diastolic BP was achieved in both groups, with no significant difference between the groups (16.1/7.9 mmHg in the intervention group versus 13.1/8.6 mmHg in the control group, P=0.3/0.7. BP control (treatment target <140/90 mmHg was achieved significantly more often in the intervention group (43% versus 25%; P=0.037; number needed to treat of 5. Adherence with home BP measurement overall was high, with a trend in favor of the intervention group (98.6% versus 96.2%; P=0.1Conclusion: Color-coded BP self-monitoring significantly improved BP control (number needed to treat of 5, meaning that every fifth patient utilizing color-coded self-monitoring achieved better BP control after 6 months, but no significant between-group difference was

  16. Visual control of prey-capture flight in dragonflies.

    Science.gov (United States)

    Olberg, Robert M

    2012-04-01

    Interacting with a moving object poses a computational problem for an animal's nervous system. This problem has been elegantly solved by the dragonfly, a formidable visual predator on flying insects. The dragonfly computes an interception flight trajectory and steers to maintain it during its prey-pursuit flight. This review summarizes current knowledge about pursuit behavior and neurons thought to control interception in the dragonfly. When understood, this system has the potential for explaining how a small group of neurons can control complex interactions with moving objects.

  17. Modification of Elementary Operational Linear Chains in Compositional Control Unit with Code Sharing

    OpenAIRE

    Aleksander, A.; Larysa, A.; Aleksander, N.

    2009-01-01

    The new design method for compositional microprogram control units with code sharing and elementarization of operational linear chains is proposed. The method targets on reduction in the number of LUT-elements in the combinational part of control unit. Some additional control microinstructions containing codes of the classes of pseudoequivalent chains are used for operational linear chains modification. Proposed method is illustrated by an example. Most desirable GSA characteristics for using...

  18. A design code to study vertical-axis wind turbine control strategies

    Science.gov (United States)

    Vachon, William A.

    1987-07-01

    A computer code called ASYM is described. The code permits a wind turbine designer to examine the role of low and high wind speed cut-in and cutout control strategies on the production of energy and the consumption of fatigue life by a wind turbine. The primary goal of the code development has been to create a design tool to optimize the energy production and the fatigue life of a wind machine through optimized high wind speed control schemes. The code is also very useful in evaluating start-up algorithms. It works primarily in the time domain and simulates high-frequency random wind of specific statistical characteristics while employing energy and damage density functions to calculate the results. A modified net present value calculation of the annual machine revenues and costs over the calculated life of the wind turbine is used to compare the merits of various control algorithms. Typical results are provided to demonstrate the use of the code.

  19. Visual control of foot placement when walking over complex terrain.

    Science.gov (United States)

    Matthis, Jonathan S; Fajen, Brett R

    2014-02-01

    The aim of this study was to investigate the role of visual information in the control of walking over complex terrain with irregularly spaced obstacles. We developed an experimental paradigm to measure how far along the future path people need to see in order to maintain forward progress and avoid stepping on obstacles. Participants walked over an array of randomly distributed virtual obstacles that were projected onto the floor by an LCD projector while their movements were tracked by a full-body motion capture system. Walking behavior in a full-vision control condition was compared with behavior in a number of other visibility conditions in which obstacles did not appear until they fell within a window of visibility centered on the moving observer. Collisions with obstacles were more frequent and, for some participants, walking speed was slower when the visibility window constrained vision to less than two step lengths ahead. When window sizes were greater than two step lengths, the frequency of collisions and walking speed were weakly affected or unaffected. We conclude that visual information from at least two step lengths ahead is needed to guide foot placement when walking over complex terrain. When placed in the context of recent research on the biomechanics of walking, the findings suggest that two step lengths of visual information may be needed because it allows walkers to exploit the passive mechanical forces inherent to bipedal locomotion, thereby avoiding obstacles while maximizing energetic efficiency. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  20. Impact of Manually Controlled Solar Shades on Indoor Visual Comfort

    Directory of Open Access Journals (Sweden)

    Jian Yao

    2016-07-01

    Full Text Available Daylight plays a significant role in sustainable building design. The purpose of this paper was to investigate the impact of manual solar shades on indoor visual comfort. A developed stochastic model for manual solar shades was modeled in Building Controls Virtual Test Bed, which was coupled with EnergyPlus for co-simulation. Movable solar shades were compared with two unshaded windows. Results show that movable solar shades have more than half of the working hours with a comfortable illuminance level, which is about twice higher than low-e windows, with a less significant daylight illuminance fluctuation. For glare protection, movable solar shades increase comfortable visual conditions by about 20% compared to low-e windows. Moreover, the intolerable glare perception could be reduced by more than 20% for movable solar shades.

  1. Human eye visual hyperacuity: Controlled diffraction for image resolution improvement

    Science.gov (United States)

    Lagunas, A.; Domínguez, O.; Martinez-Conde, S.; Macknik, S. L.; Del-Río, C.

    2017-09-01

    The Human Visual System appears to be using a low number of sensors for image capturing, and furthermore, regarding the physical dimensions of cones—photoreceptors responsible for the sharp central vision—we may realize that these sensors are of a relatively small size and area. Nonetheless, the human eye is capable of resolving fine details thanks to visual hyperacuity and presents an impressive sensitivity and dynamic range when set against conventional digital cameras of similar characteristics. This article is based on the hypothesis that the human eye may be benefiting from diffraction to improve both image resolution and acquisition process. The developed method involves the introduction of a controlled diffraction pattern at an initial stage that enables the use of a limited number of sensors for capturing the image and makes possible a subsequent post-processing to improve the final image resolution.

  2. A visual motion detecting module for dragonfly-controlled robots.

    Science.gov (United States)

    Pham, Thuy T; Higgins, Charles M

    2014-01-01

    When imitating biological sensors, we have not completely understood the early processing of the input to reproduce artificially. Building hybrid systems with both artificial and real biological components is a promising solution. For example, when a dragonfly is used as a living sensor, the early processing of visual information is performed fully in the brain of the dragonfly. The only significant remaining tasks are recording and processing neural signals in software and/or hardware. Based on existing works which focused on recording neural signals, this paper proposes a software application of neural information processing to design a visual processing module for dragonfly hybrid bio-robots. After a neural signal is recorded in real-time, the action potentials can be detected and matched with predefined templates to detect when and which descending neurons fire. The output of the proposed system will be used to control other parts of the robot platform.

  3. High-frequency combination coding-based steady-state visual evoked potential for brain computer interface

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Feng; Zhang, Xin; Xie, Jun; Li, Yeping; Han, Chengcheng; Lili, Li; Wang, Jing [School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); Xu, Guang-Hua [School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710054 (China)

    2015-03-10

    This study presents a new steady-state visual evoked potential (SSVEP) paradigm for brain computer interface (BCI) systems. The goal of this study is to increase the number of targets using fewer stimulation high frequencies, with diminishing subject’s fatigue and reducing the risk of photosensitive epileptic seizures. The new paradigm is High-Frequency Combination Coding-Based High-Frequency Steady-State Visual Evoked Potential (HFCC-SSVEP).Firstly, we studied SSVEP high frequency(beyond 25 Hz)response of SSVEP, whose paradigm is presented on the LED. The SNR (Signal to Noise Ratio) of high frequency(beyond 40 Hz) response is very low, which is been unable to be distinguished through the traditional analysis method; Secondly we investigated the HFCC-SSVEP response (beyond 25 Hz) for 3 frequencies (25Hz, 33.33Hz, and 40Hz), HFCC-SSVEP produces n{sup n} with n high stimulation frequencies through Frequence Combination Code. Further, Animproved Hilbert-huang transform (IHHT)-based variable frequency EEG feature extraction method and a local spectrum extreme target identification algorithmare adopted to extract time-frequency feature of the proposed HFCC-SSVEP response.Linear predictions and fixed sifting (iterating) 10 time is used to overcome the shortage of end effect and stopping criterion,generalized zero-crossing (GZC) is used to compute the instantaneous frequency of the proposed SSVEP respondent signals, the improved HHT-based feature extraction method for the proposed SSVEP paradigm in this study increases recognition efficiency, so as to improve ITR and to increase the stability of the BCI system. what is more, SSVEPs evoked by high-frequency stimuli (beyond 25Hz) minimally diminish subject’s fatigue and prevent safety hazards linked to photo-induced epileptic seizures, So as to ensure the system efficiency and undamaging.This study tests three subjects in order to verify the feasibility of the proposed method.

  4. Using game theory for perceptual tuned rate control algorithm in video coding

    Science.gov (United States)

    Luo, Jiancong; Ahmad, Ishfaq

    2005-03-01

    This paper proposes a game theoretical rate control technique for video compression. Using a cooperative gaming approach, which has been utilized in several branches of natural and social sciences because of its enormous potential for solving constrained optimization problems, we propose a dual-level scheme to optimize the perceptual quality while guaranteeing "fairness" in bit allocation among macroblocks. At the frame level, the algorithm allocates target bits to frames based on their coding complexity. At the macroblock level, the algorithm distributes bits to macroblocks by defining a bargaining game. Macroblocks play cooperatively to compete for shares of resources (bits) to optimize their quantization scales while considering the Human Visual System"s perceptual property. Since the whole frame is an entity perceived by viewers, macroblocks compete cooperatively under a global objective of achieving the best quality with the given bit constraint. The major advantage of the proposed approach is that the cooperative game leads to an optimal and fair bit allocation strategy based on the Nash Bargaining Solution. Another advantage is that it allows multi-objective optimization with multiple decision makers (macroblocks). The simulation results testify the algorithm"s ability to achieve accurate bit rate with good perceptual quality, and to maintain a stable buffer level.

  5. Coding for stimulus velocity by temporal patterning of spike discharges in visual cells of cat superior colliculus.

    Science.gov (United States)

    Mandl, G

    1993-07-01

    Statistical analyses, performed on extracellularly recorded spike trains generated by 69 single motion sensitive visual cells in the intermediate layers of superior colliculi of pretrigeminal cat preparations, revealed that--even in the unstimulated condition (38/69)--most neuronal spike discharge patterns tended to switch between two stochastically distinct states, in the form of rapidly alternating "bursting" (high frequency) and "resting" (low frequency) episodes. The numbers of consecutive interspike intervals within a given state were, as a rule, independent integer-valued random variables with discrete probability distributions, in essential agreement with the semi-Markov model proposed by Ekholm and Hyvärinen [(1970) Biophysical Journal, 10, 773-796]. The introduction of visual stimuli (47/69) moving with velocities of 2-160 deg/sec caused systematic and reproducible changes in the ratio of bursting to resting activities, decreases in overall discharge variability, and increases in signal transinformation flow. Moreover, with one group of stimulated cells (28/47), increasing stimulus velocity caused increasingly precise ("stimulus-forced") synchronization of bursting episodes with specific phases of stimulus movement; while for a smaller group (12/47), stimulus-related alternations between bursting and resting states assumed the form of semi-rhythmical burst discharges within the characteristic 60-80 Hz "gamma oscillation" range ("stimulus-induced" synchronization). For a minority of cells (7/47), switching between bursting and resting states--although characteristically modified by stimulus velocity--remained largely desynchronized with all phases of stimulus transit. It was argued that such temporal patterns of discharge may constitute elements of a candidate "distribution" code for movement detection by the cat visual system.

  6. Visually Improved Image Compression by using Embedded Zero-tree Wavelet Coding

    Directory of Open Access Journals (Sweden)

    Janaki R

    2011-03-01

    Full Text Available Image compression is very important for efficient transmission and storage of images. Embedded Zero- tree Wavelet (EZW algorithm is a simple yet powerful algorithm having the property that the bits in the stream are generated in the order of their importance. Image compression can improve the performance of the digital systems by reducing time and cost in image storage and transmission without significant reduction of the image quality. For image compression it is desirable that the selection of transform should reduce the size of resultant data set as compared to source data set. EZW is computationally very fast and among the best image compression algorithm known today. This paper proposes a technique for image compression which uses the Wavelet-based Image Coding. A large number of experimental results are shown that this method saves a lot of bits in transmission, further enhances the compression performance. This paper aims to determine the best threshold to compress the still image at a particular decomposition level by using Embedded Zero-tree Wavelet encoder. Compression Ratio (CR and Peak-Signal-to-Noise (PSNR is determined for different threshold values ranging from 6 to 60 for decomposition level 8.

  7. Cognitive Control Network Contributions to Memory-Guided Visual Attention.

    Science.gov (United States)

    Rosen, Maya L; Stern, Chantal E; Michalka, Samantha W; Devaney, Kathryn J; Somers, David C

    2016-05-01

    Visual attentional capacity is severely limited, but humans excel in familiar visual contexts, in part because long-term memories guide efficient deployment of attention. To investigate the neural substrates that support memory-guided visual attention, we performed a set of functional MRI experiments that contrast long-term, memory-guided visuospatial attention with stimulus-guided visuospatial attention in a change detection task. Whereas the dorsal attention network was activated for both forms of attention, the cognitive control network(CCN) was preferentially activated during memory-guided attention. Three posterior nodes in the CCN, posterior precuneus, posterior callosal sulcus/mid-cingulate, and lateral intraparietal sulcus exhibited the greatest specificity for memory-guided attention. These 3 regions exhibit functional connectivity at rest, and we propose that they form a subnetwork within the broader CCN. Based on the task activation patterns, we conclude that the nodes of this subnetwork are preferentially recruited for long-term memory guidance of visuospatial attention.

  8. Simple Instrumental and Visual Tests for Nonlaboratory Environmental Control

    Directory of Open Access Journals (Sweden)

    L. P. Eksperiandova

    2016-01-01

    Full Text Available Proposed are simple and available techniques that can be used for rapid and reliable environmental control specifically of natural water by means of instrumental and visual tests in outdoor conditions. Developed are the chemical colorimetric modes for fast detection of socially dangerous trace impurities in water such as Co(II, Pd(II, and Rh(III as well as NO2--ions and Fe(III serving as model impurities. Application of portable digital devices and scanner allows estimating the color coordinates and increasing the accuracy and sensitivity of the tests. The combination of complex formation with preconcentration of colored complexes replaces the sensitive but time-consuming and capricious kinetic method that is usually used for this purpose at the more convenient and reliable colorimetric method. As the test tools, the following ones are worked out: polyurethane foam tablets with sorbed colored complexes, the two-layer paper sandwich packaged in slide adapter and saturated by reagents, and polyethylene terephthalate blister with dried reagents. Fast analysis of polyurethane foam tablets is realized using a pocket digital RGB-colorimeter or portable photometer. Express analysis of two-layer paper sandwich or polyethylene terephthalate blister is realized by visual and instrumental tests. The metrological characteristics of the developed visual and instrumental express analysis techniques are estimated.

  9. Inhibitory stabilization and visual coding in cortical circuits with multiple interneuron subtypes.

    Science.gov (United States)

    Litwin-Kumar, Ashok; Rosenbaum, Robert; Doiron, Brent

    2016-03-01

    Recent anatomical and functional characterization of cortical inhibitory interneurons has highlighted the diverse computations supported by different subtypes of interneurons. However, most theoretical models of cortex do not feature multiple classes of interneurons and rather assume a single homogeneous population. We study the dynamics of recurrent excitatory-inhibitory model cortical networks with parvalbumin (PV)-, somatostatin (SOM)-, and vasointestinal peptide-expressing (VIP) interneurons, with connectivity properties motivated by experimental recordings from mouse primary visual cortex. Our theory describes conditions under which the activity of such networks is stable and how perturbations of distinct neuronal subtypes recruit changes in activity through recurrent synaptic projections. We apply these conclusions to study the roles of each interneuron subtype in disinhibition, surround suppression, and subtractive or divisive modulation of orientation tuning curves. Our calculations and simulations determine the architectural and stimulus tuning conditions under which cortical activity consistent with experiment is possible. They also lead to novel predictions concerning connectivity and network dynamics that can be tested via optogenetic manipulations. Our work demonstrates that recurrent inhibitory dynamics must be taken into account to fully understand many properties of cortical dynamics observed in experiments.

  10. A Multimedia Visual Feedback in the Web-controlled Laboratory

    Directory of Open Access Journals (Sweden)

    J. Turan

    2012-06-01

    Full Text Available The paper presents development work related to create WWW based remote control laboratory for teaching Applied Photonics. In order to minimize the cost at the end-user domain, simple WWW browser with fundamental plug-in (Java applets, HTML Pages and LabWindows applets to support the remote control and video transmission functionality of the remote control is proposed. As for telepresence and monitoring of device actions, a simple type zooming web-camera is connected to the hosting multimedia PC via the USB port. The web-camera assists in visual feedback of the system and presents the feeling of telepresence for the end-user (student. USB web-cameras are normally efficient and the presence of another video server is not necessary in this case, thanks to LabWindows.

  11. Temperature and oxygen visual estimator for carbonization process control

    Science.gov (United States)

    Martínez, Fredy; Martínez, Fernando; Montiel, Holman

    2017-02-01

    This paper proposes a visual estimator for temperature and oxygen content for closed loop control of carbonization furnace in the production of activated carbon. The carbonization process involves thermal decomposition of vegetal material in the absence of air; this requires rigorous sensing and control of these two variables. The system consists of two cameras, a thermographic camera to estimate the temperature, and a traditional digital camera to estimate the oxygen content. In both cases we use similarity measures between images to estimate the value of the variables into the furnace, estimation that is used to control the furnace flame. The algorithm is tested with reference photos taken at the production plant, and the experimental results prove the performance of the proposed technique.

  12. Ankylosing Spondylitis and Posture Control: The Role of Visual Input

    Directory of Open Access Journals (Sweden)

    Alessandro Marco De Nunzio

    2015-01-01

    Full Text Available Objectives. To assess the motor control during quiet stance in patients with established ankylosing spondylitis (AS and to evaluate the effect of visual input on the maintenance of a quiet posture. Methods. 12 male AS patients (mean age 50.1 ± 13.2 years and 12 matched healthy subjects performed 2 sessions of 3 trials in quiet stance, with eyes open (EO and with eyes closed (EC on a baropodometric platform. The oscillation of the centre of feet pressure (CoP was acquired. Indices of stability and balance control were assessed by the sway path (SP of the CoP, the frequency bandwidth (FB1 that includes the 80% of the area under the amplitude spectrum, the mean amplitude of the peaks (MP of the sway density curve (SDC, and the mean distance (MD between 2 peaks of the SDC. Results. In severe AS patients, the MD between two peaks of the SDC and the SP of the center of feet pressure were significantly higher than controls during both EO and EC conditions. The MP was significantly reduced just on EC. Conclusions. Ankylosing spondylitis exerts negative effect on postural stability, not compensable by visual inputs. Our findings may be useful in the rehabilitative management of the increased risk of falling in AS.

  13. Losing the big picture: how religion may control visual attention.

    Directory of Open Access Journals (Sweden)

    Lorenza S Colzato

    Full Text Available Despite the abundance of evidence that human perception is penetrated by beliefs and expectations, scientific research so far has entirely neglected the possible impact of religious background on attention. Here we show that Dutch Calvinists and atheists, brought up in the same country and culture and controlled for race, intelligence, sex, and age, differ with respect to the way they attend to and process the global and local features of complex visual stimuli: Calvinists attend less to global aspects of perceived events, which fits with the idea that people's attentional processing style reflects possible biases rewarded by their religious belief system.

  14. Visual control of movement patterns and the grammar of action.

    Science.gov (United States)

    Smyth, M M

    1989-05-01

    In this experiment adult subjects copied three types of material (letters, reversed letters and geometric shapes) with and without sight of the hand and the writing trace. Without vision the number of movement segments decreased and the sequence and direction of movements were altered. This means that subjects did not use a fixed stored representation to produce items nor did they obey the rules of Goodnow and Levine's (1973) grammar of action. When spatial location is made more difficult by the removal of vision, movement production is simplified to reduce the number of relocations required. The use of consistent directions of movement depends on the ability to use visual control of spatial location.

  15. A Toroidally Symmetric Plasma Simulation code for design of position and shape control on tokamak plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Takase, Haruhiko [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment; Senda, Ikuo

    1999-04-01

    A Toroidally Symmetric Plasma Simulation (TSPS) code has been developed for investigating the position and shape control on tokamak plasmas. The analyses of three-dimensional eddy currents on the conducting components around the plasma and the two-dimensional magneto-hydrodynamic (MHD) equilibrium are taken into account in this code. The code can analyze the plasma position and shape control during the minor disruption in which the deformation of plasma is not negligible. Using the ITER (International Thermonuclear Experimental Reactor) parameters, some examples of calculations are shown in this paper. (author)

  16. Visual control in children with developmental dyslexia Controle visual em crianças com dislexia do desenvolvimento

    Directory of Open Access Journals (Sweden)

    Stella Maris Costa Castro

    2008-12-01

    Full Text Available PURPOSE: To assess binocular control in children with dyslexia. METHODS: Cross-sectional study with 26 children who were submitted to a set of ophthalmologic and visual tests. RESULTS: In the dyslexic children less eye movement control in voluntary convergence and unstable binocular fixation was observed. CONCLUSION: The results support the hypothesis that developmental dyslexia might present deficits which involve the magnocellular pathway and a part of the posterior cortical attentional network.OBJETIVO: Avaliar o controle binocular em crianças com dislexia. MÉTODOS: Estudo transversal do qual participaram 26 crianças, nas quais foram aplicadas uma série de exames oftalmológicos e visuais. RESULTADOS: Nas crianças com dislexia observou-se controle menor na convergência voluntária e na estabilidade da fixação binocular. CONCLUSÃO: Os resultados apóiam a hipótese de que na dislexia do desenvolvimento podem ocorrer déficits que envolvem a via visual magnocelular e uma parte da rede cortical posterior da atenção.

  17. Adaptive efficient video transmission over the Internet based on congestion control and RS coding

    Institute of Scientific and Technical Information of China (English)

    黄伟红; 张福炎; 孙正兴

    2002-01-01

    An approach based on adaptive congestion control and adaptive error recovery with RS (Reed-Solomon) coding method is presented for efficient video transmission over the Internet.Featured by weighted moving average rate control and TCP-fdendliness,AVSP,a novel adaptive video streaming protocol,is designed with adjustable rate control parameters so as to respond quickly to the QoS status fluctuation during video transmission over the Internet.Combined with congestion control policy,an adaptive RS coding error recovery scheme with variable parameters is presented to enhance the robustness of MPEG video transmission over the Intemet with restriction to the total system bandwidth.``

  18. Development of a Top-View Numeric Coding Teaching-Learning Trajectory within an Elementary Grades 3-D Visualization Design Research Project

    Science.gov (United States)

    Sack, Jacqueline J.

    2013-01-01

    This article explicates the development of top-view numeric coding of 3-D cube structures within a design research project focused on 3-D visualization skills for elementary grades children. It describes children's conceptual development of 3-D cube structures using concrete models, conventional 2-D pictures and abstract top-view numeric…

  19. Development of a Top-View Numeric Coding Teaching-Learning Trajectory within an Elementary Grades 3-D Visualization Design Research Project

    Science.gov (United States)

    Sack, Jacqueline J.

    2013-01-01

    This article explicates the development of top-view numeric coding of 3-D cube structures within a design research project focused on 3-D visualization skills for elementary grades children. It describes children's conceptual development of 3-D cube structures using concrete models, conventional 2-D pictures and abstract top-view numeric…

  20. Reed-Muller Codes for Peak Power Control in Multicarrier CDMA

    CERN Document Server

    Yu, Nam Yul

    2010-01-01

    Reed-Muller codes are studied for peak power control in multicarrier code-division multiple access (MC-CDMA) communication systems. In a coded MC-CDMA system, the information data multiplexed from users is encoded by a Reed-Muller subcode and the codeword is fully-loaded to Walsh-Hadamard spreading sequences. The polynomial representation of a coded MC-CDMA signal is established for theoretical analysis of the peak-to-average power ratio (PAPR). The Reed-Muller subcodes are defined in a recursive way by the Boolean functions providing the transmitted MC-CDMA signals with the bounded PAPR as well as the error correction capability. A connection between the code rates and the maximum PAPR is theoretically investigated in the coded MC-CDMA. Simulation results present the statistical evidence that the PAPR of the coded MC-CDMA signal is not only theoretically bounded, but also statistically reduced. In particular, the coded MC-CDMA solves the major PAPR problem of uncoded MC-CDMA by dramatically reducing its PAPR...

  1. Therapeutic Options for Controlling Fluids in the Visual System

    Science.gov (United States)

    Curry, Kristina M.; Wotring, Virginia E.

    2014-01-01

    Visual Impairment/Intracranial Pressure (VIIP) is a newly recognized risk at NASA. The VIIP project examines the effect of long-term exposure to microgravity on vision of crewmembers before and after they return to Earth. Diamox (acetazolamide) is a medication which is used to decrease intraocular pressure; however, it carries a 3% risk of kidney stones. Astronauts are at a higher risk of kidney stones during spaceflight and the use Diamox would only increase the risk; therefore alternative therapies were investigated. Histamine 2 (H2) antagonist acid blockers such as cimetidine, ranitidine, famotidine and nizatidine are typically used to relieve the symptoms of gastroesophageal reflux disease (GERD). H2 receptors have been found in the human visual system, which has led to research on the use of H2 antagonist blockers to control fluid production in the human eye. Another potential therapeutic strategy is targeted at aquaporins, which are water channels that help maintain fluid homeostasis. Aquaporin antagonists are also known to affect intracranial pressure which can in turn alter intraocular pressure. Studies on aquaporin antagonists suggest high potential for effective treatment. The primary objective of this investigation is to review existing research on alternate medications or therapy to significantly reduce intracranial and intraocular pressure. A literature review was conducted. Even though we do not have all the answers quite yet, a considerable amount of information was discovered, and findings were narrowed, which should allow for more conclusive answers to be found in the near future.

  2. Auto Code Generation for Simulink-Based Attitude Determination Control System

    Science.gov (United States)

    MolinaFraticelli, Jose Carlos

    2012-01-01

    This paper details the work done to auto generate C code from a Simulink-Based Attitude Determination Control System (ADCS) to be used in target platforms. NASA Marshall Engineers have developed an ADCS Simulink simulation to be used as a component for the flight software of a satellite. This generated code can be used for carrying out Hardware in the loop testing of components for a satellite in a convenient manner with easily tunable parameters. Due to the nature of the embedded hardware components such as microcontrollers, this simulation code cannot be used directly, as it is, on the target platform and must first be converted into C code; this process is known as auto code generation. In order to generate C code from this simulation; it must be modified to follow specific standards set in place by the auto code generation process. Some of these modifications include changing certain simulation models into their atomic representations which can bring new complications into the simulation. The execution order of these models can change based on these modifications. Great care must be taken in order to maintain a working simulation that can also be used for auto code generation. After modifying the ADCS simulation for the auto code generation process, it is shown that the difference between the output data of the former and that of the latter is between acceptable bounds. Thus, it can be said that the process is a success since all the output requirements are met. Based on these results, it can be argued that this generated C code can be effectively used by any desired platform as long as it follows the specific memory requirements established in the Simulink Model.

  3. Optimal Rate Control in H.264 Video Coding Based on Video Quality Metric

    Directory of Open Access Journals (Sweden)

    R. Karthikeyan

    2014-05-01

    Full Text Available The aim of this research is to find a method for providing better visual quality across the complete video sequence in H.264 video coding standard. H.264 video coding standard with its significantly improved coding efficiency finds important applications in various digital video streaming, storage and broadcast. To achieve comparable quality across the complete video sequence with the constrains on bandwidth availability and buffer fullness, it is important to allocate more bits to frames with high complexity or a scene change and fewer bits to other less complex frames. A frame layer bit allocation scheme is proposed based on the perceptual quality metric as indicator of the frame complexity. The proposed model computes the Quality Index ratio (QIr of the predicted quality index of the current frame to the average quality index of all the previous frames in the group of pictures which is used for bit allocation to the current frame along with bits computed based on buffer availability. The standard deviation of the perceptual quality indicator MOS computed for the proposed model is significantly less which means the quality of the video sequence is identical throughout the full video sequence. Thus the experiment results shows that the proposed model effectively handles the scene changes and scenes with high motion for better visual quality.

  4. Visual input enhancement via essay coding results in deaf learners' long-term retention of improved English grammatical knowledge.

    Science.gov (United States)

    Berent, Gerald P; Kelly, Ronald R; Schmitz, Kathryn L; Kenney, Patricia

    2009-01-01

    This study explored the efficacy of visual input enhancement, specifically essay enhancement, for facilitating deaf college students' improvement in English grammatical knowledge. Results documented students' significant improvement immediately after a 10-week instructional intervention, a replication of recent research. Additionally, the results of delayed assessment documented students' significant retention of that improvement five and a half months beyond the instructional intervention period. Essay enhancement served to highlight, via a coding procedure, students' successful and unsuccessful production of discourse-required target grammatical structures. The procedure converted students' written communicative output into enhanced input for inducing noticing of grammatical form and, through essay revision, establishing form-meaning connections leading to acquisition. With its optimal design characteristics supported by theoretical and empirical research, essay enhancement is a highly effective methodology that can be easily implemented as primary or supplementary English instruction for deaf students. The results of this study hold great promise for facilitating deaf students' English language and literacy development and have broad implications for second-language research, teaching, and learning.

  5. Controller routines for the DECsystem-10 with application to a tandem-mirror plasma code

    Energy Technology Data Exchange (ETDEWEB)

    Faul, D.R.; Devoto, R.S.

    1979-04-12

    FORTRAN-callable subroutines have been written to enable controller--controllee interaction on the LLL DECsystem-10. These subroutines have been used to construct a controller (XTCTMR) for a tandem-mirror physics code (CTCTMR). A description of the subroutines and their use is presented. Also, sample results are given.

  6. Training and support to improve ICD coding quality: A controlled before-and-after impact evaluation

    Directory of Open Access Journals (Sweden)

    Robin Dyers

    2017-06-01

    Full Text Available Background. The proposed National Health Insurance policy for South Africa (SA requires hospitals to maintain high-quality International Statistical Classification of Diseases (ICD codes for patient records. While considerable strides had been made to improve ICD coding coverage by digitising the discharge process in the Western Cape Province, further intervention was required to improve data quality. The aim of this controlled before-and-after study was to evaluate the impact of a clinician training and support initiative to improve ICD coding quality. Objective. To compare ICD coding quality between two central hospitals in the Western Cape before and after the implementation of a training and support initiative for clinicians at one of the sites. Methods. The difference in differences in data quality between the intervention site and the control site was calculated. Multiple logistic regression was also used to determine the odds of data quality improvement after the intervention and to adjust for potential differences between the groups. Results. The intervention had a positive impact of 38.0% on ICD coding completeness over and above changes that occurred at the control site. Relative to the baseline, patient records at the intervention site had a 6.6 (95% confidence interval 3.5 - 16.2 adjusted odds ratio of having a complete set of ICD codes for an admission episode after the introduction of the training and support package. The findings on impact on ICD coding accuracy were not significant. Conclusion. There is sufficient pragmatic evidence that a training and support package will have a considerable positive impact on ICD coding completeness in the SA setting.

  7. A review on synchronous CDMA systems: optimum overloaded codes, channel capacity, and power control

    Directory of Open Access Journals (Sweden)

    Hosseini Seyed Amirhossein

    2011-01-01

    Full Text Available Abstract This paper is a tutorial review on important issues related to code-division multiple-access (CDMA systems such as channel capacity, power control, and optimum codes; specifically, we consider optimum overloaded codes that achieve errorless transmission in the absence of noise for the binary and nonbinary cases. A survey of lower and upper bounds for the sum channel capacity of such systems is given in the presence and absence of channel noise. The asymptotic results for the channel capacity are also investigated. The channel capacity, errorless transmission codes, and power estimation for near-far effects are also explored. The emphasis of this tutorial review is on the overloaded CDMA systems.

  8. Efficient rate control scheme for low bit rate H.264/AVC video coding

    Institute of Scientific and Technical Information of China (English)

    LI Zhi-cheng; ZHANG Yong-jun; LIU Tao; GU Wan-yi

    2009-01-01

    This article presents an efficient rate control scheme for H.264/AVC video coding in low bit rate environment. In the proposed scheme, an improved rate-distortion (RD) model by both analytical and empirical approaches is developed. It involves an enhanced mean absolute difference estimating method and a more rate-robust distortion model. Based on this RD model, an efficient macroblock-layer rate control scheme for H.264/AVC video coding is proposed. Experimental results show that this model encodes video sequences with higher peak signal-to-noise ratio gains and generates bit stream closer to the target rate.

  9. Development of visual 3D virtual environment for control software

    Science.gov (United States)

    Hirose, Michitaka; Myoi, Takeshi; Amari, Haruo; Inamura, Kohei; Stark, Lawrence

    1991-01-01

    Virtual environments for software visualization may enable complex programs to be created and maintained. A typical application might be for control of regional electric power systems. As these encompass broader computer networks than ever, construction of such systems becomes very difficult. Conventional text-oriented environments are useful in programming individual processors. However, they are obviously insufficient to program a large and complicated system, that includes large numbers of computers connected to each other; such programming is called 'programming in the large.' As a solution for this problem, the authors are developing a graphic programming environment wherein one can visualize complicated software in virtual 3D world. One of the major features of the environment is the 3D representation of concurrent process. 3D representation is used to supply both network-wide interprocess programming capability (capability for 'programming in the large') and real-time programming capability. The authors' idea is to fuse both the block diagram (which is useful to check relationship among large number of processes or processors) and the time chart (which is useful to check precise timing for synchronization) into a single 3D space. The 3D representation gives us a capability for direct and intuitive planning or understanding of complicated relationship among many concurrent processes. To realize the 3D representation, a technology to enable easy handling of virtual 3D object is a definite necessity. Using a stereo display system and a gesture input device (VPL DataGlove), our prototype of the virtual workstation has been implemented. The workstation can supply the 'sensation' of the virtual 3D space to a programmer. Software for the 3D programming environment is implemented on the workstation. According to preliminary assessments, a 50 percent reduction of programming effort is achieved by using the virtual 3D environment. The authors expect that the 3D

  10. Visualization and Quality Control Web Tools for CERES Products

    Science.gov (United States)

    Mitrescu, C.; Doelling, D.; Chu, C.; Mlynczak, P.

    2014-12-01

    The CERES project continues to provide the scientific community a wide variety of satellite-derived data products. The flagship products TOA broadband shortwave and longwave observed fluxes, computed TOA and Surface fluxes, as well as cloud, aerosol, and other atmospheric parameters. These datasets encompass a wide range of temporal and spatial resolutions, suited to specific applications. We thus offer time resolutions that range from instantaneous to monthly means, with spatial resolutions that range from 20-km footprint to global scales. The 14-year record is mostly used by climate modeling communities that focus on global mean energetics, meridianal heat transport, and climate trend studies. CERES products are also used by the remote sensing community for their climatological studies. In the last years however, our CERES products had been used by an even broader audience, like the green energy, health and environmental research communities, and others. Because of that, the CERES project has implemented a now well-established web-oriented Ordering and Visualization Tool (OVT), which is well into its fifth year of development. In order to help facilitate a comprehensive quality control of CERES products, the OVT Team began introducing a series of specialized functions. These include the 1- and 2-D histogram, anomaly, deseasonalization, temporal and spatial averaging, side-by-side parameter comparison, and other specialized scientific application capabilities. Over time increasingly higher order temporal and spatial resolution products are being made available to the public through the CERES OVT. These high-resolution products require accessing the existing long-term archive - thus the reading of many very large netCDF or HDF files that pose a real challenge to the task of near instantaneous visualization. An overview of the CERES OVT basic functions and QC capabilities as well as future steps in expanding its capabilities will be presented at the meeting.

  11. CONTROL STRATEGY FOR ELECTROHYDRAULIC POSITION SERVO SYSTEM WITH GENERALIZED PULSE CODE MODULATION

    Institute of Scientific and Technical Information of China (English)

    LIU Rong; PAN Huachen; CHEN Ying

    2007-01-01

    A hybrid control strategy has been designed and developed for the electro-hydraulic position servo control system with generalized Pulse code modulation (GPCM), which is suitable for the area where the work condition is poor and a large flow rate is required. It is difficult to control the GPCM system because the system is discrete. With consideration of the stability and speediness of the GPCM position servo control system, a control strategy is developed through the theoretical and experimental analyses. The control strategy integrates the merits of Bang-Bang control, PID control and fuzzy control. With this hybrid control strategy, the electro hydraulic control system has good performances, and the servo control is carried out with GPCM through on-offvalves.

  12. Data Presentation and Visualization (DPV) Interface Control Document

    Science.gov (United States)

    Mazzone, Rebecca A.; Conroy, Michael P.

    2015-01-01

    Data Presentation and Visualization (DPV) is a subset of the modeling and simulation (M&S) capabilities at Kennedy Space Center (KSC) that endeavors to address the challenges of how to present and share simulation output for analysts, stakeholders, decision makers, and other interested parties. DPV activities focus on the development and provision of visualization tools to meet the objectives identified above, as well as providing supporting tools and capabilities required to make its visualization products available and accessible across NASA.

  13. Project of decree relative to the licensing and statement system of nuclear activities and to their control and bearing various modifications of the public health code and working code; Projet de decret relatif au regime d'autorisation et de declaration des activites nucleaires et a leur controle et portant diverses modifications du code de la sante publique et du code du travail

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This decree concerns the control of high level sealed radioactive sources and orphan sources. It has for objective to introduce administrative simplification, especially the radiation sources licensing and statement system, to reinforce the control measures planed by the public health code and by the employment code, to bring precision and complements in the editing of several already existing arrangements. (N.C.)

  14. Wind turbine control systems: Dynamic model development using system identification and the fast structural dynamics code

    Energy Technology Data Exchange (ETDEWEB)

    Stuart, J.G.; Wright, A.D.; Butterfield, C.P.

    1996-10-01

    Mitigating the effects of damaging wind turbine loads and responses extends the lifetime of the turbine and, consequently, reduces the associated Cost of Energy (COE). Active control of aerodynamic devices is one option for achieving wind turbine load mitigation. Generally speaking, control system design and analysis requires a reasonable dynamic model of {open_quotes}plant,{close_quotes} (i.e., the system being controlled). This paper extends the wind turbine aileron control research, previously conducted at the National Wind Technology Center (NWTC), by presenting a more detailed development of the wind turbine dynamic model. In prior research, active aileron control designs were implemented in an existing wind turbine structural dynamics code, FAST (Fatigue, Aerodynamics, Structures, and Turbulence). In this paper, the FAST code is used, in conjunction with system identification, to generate a wind turbine dynamic model for use in active aileron control system design. The FAST code is described and an overview of the system identification technique is presented. An aileron control case study is used to demonstrate this modeling technique. The results of the case study are then used to propose ideas for generalizing this technique for creating dynamic models for other wind turbine control applications.

  15. Case studies on design, simulation and visualization of control and measurement applications using REX control system

    Science.gov (United States)

    Ozana, Stepan; Pies, Martin; Docekal, Tomas

    2016-06-01

    REX Control System is a professional advanced tool for design and implementation of complex control systems that belongs to softPLC category. It covers the entire process starting from simulation of functionality of the application before deployment, through implementation on real-time target, towards analysis, diagnostics and visualization. Basically it consists of two parts: the development tools and the runtime system. It is also compatible with Simulink environment, and the way of implementation of control algorithm is very similar. The control scheme is finally compiled (using RexDraw utility) and uploaded into a chosen real-time target (using RexView utility). There is a wide variety of hardware platforms and real-time operating systems supported by REX Control System such as for example Windows Embedded, Linux, Linux/Xenomai deployed on SBC, IPC, PAC, Raspberry Pi and others with many I/O interfaces. It is modern system designed both for measurement and control applications, offering a lot of additional functions concerning data archiving, visualization based on HTML5, and communication standards. The paper will sum up possibilities of its use in educational process, focused on control of case studies of physical models with classical and advanced control algorithms.

  16. Case studies on design, simulation and visualization of control and measurement applications using REX control system

    Energy Technology Data Exchange (ETDEWEB)

    Ozana, Stepan, E-mail: stepan.ozana@vsb.cz; Pies, Martin, E-mail: martin.pies@vsb.cz; Docekal, Tomas, E-mail: docekalt@email.cz [VSB-Technical University of Ostrava, Faculty of Electrical Engineering and Computer Science, Department of Cybernetics and Biomedical Engineering, 17. listopadu 15/2172, Ostrava-Poruba, 700 30 (Czech Republic)

    2016-06-08

    REX Control System is a professional advanced tool for design and implementation of complex control systems that belongs to softPLC category. It covers the entire process starting from simulation of functionality of the application before deployment, through implementation on real-time target, towards analysis, diagnostics and visualization. Basically it consists of two parts: the development tools and the runtime system. It is also compatible with Simulink environment, and the way of implementation of control algorithm is very similar. The control scheme is finally compiled (using RexDraw utility) and uploaded into a chosen real-time target (using RexView utility). There is a wide variety of hardware platforms and real-time operating systems supported by REX Control System such as for example Windows Embedded, Linux, Linux/Xenomai deployed on SBC, IPC, PAC, Raspberry Pi and others with many I/O interfaces. It is modern system designed both for measurement and control applications, offering a lot of additional functions concerning data archiving, visualization based on HTML5, and communication standards. The paper will sum up possibilities of its use in educational process, focused on control of case studies of physical models with classical and advanced control algorithms.

  17. Using Automatic Code Generation in the Attitude Control Flight Software Engineering Process

    Science.gov (United States)

    McComas, David; O'Donnell, James R., Jr.; Andrews, Stephen F.

    1999-01-01

    This paper presents an overview of the attitude control subsystem flight software development process, identifies how the process has changed due to automatic code generation, analyzes each software development phase in detail, and concludes with a summary of our lessons learned.

  18. Using Automatic Code Generation in the Attitude Control Flight Software Engineering Process

    Science.gov (United States)

    McComas, David; O'Donnell, James R., Jr.; Andrews, Stephen F.

    1999-01-01

    This paper presents an overview of the attitude control subsystem flight software development process, identifies how the process has changed due to automatic code generation, analyzes each software development phase in detail, and concludes with a summary of our lessons learned.

  19. Power Control and Coding Formulation for State Estimation with Wireless Sensors

    DEFF Research Database (Denmark)

    Quevedo, Daniel; Østergaard, Jan; Ahlen, Anders

    2014-01-01

    Technological advances made wireless sensors cheap and reliable enough to be brought into industrial use. A major challenge arises from the fact that wireless channels introduce random packet dropouts. Power control and coding are key enabling technologies in wireless communications to ensure eff...

  20. 27 CFR 73.12 - What security controls must I use for identification codes and passwords?

    Science.gov (United States)

    2010-04-01

    ... Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY (CONTINUED) PROCEDURES AND PRACTICES ELECTRONIC SIGNATURES; ELECTRONIC SUBMISSION OF FORMS Electronic Signatures § 73.12 What security controls must I use for identification codes and passwords? If you use electronic signatures based upon...

  1. Uncalibrated Neuro-Visual Servoing Control for Multiple Robot Arms

    Directory of Open Access Journals (Sweden)

    Rodolfo García-Rodríguez

    2013-09-01

    Full Text Available Diverse image-based tracking schemes for a robot moving in free motion have been proposed and experimentally validated. However, few visual servoing schemes have addressed the tracking of the desired trajectory and the contact forces for multiple robot arms. The main difficulty stems from the fact that camera information cannot be used to drive force trajectories. Recognizing this fact, a unique error manifold that includes position-velocity and force errors in orthogonal complements is proposed. A synergistic scheme that fuses camera, encoder and force sensor signals into a unique error manifold allows proposing a control system which guarantees exponential tracking errors under parametric uncertainty. Additionally a small neural network driven by a second order sliding mode surface is derived to compensate robot dynamics. Residual errors that arise because of the finite size of the neural network are compensated via an orthogonalized second order sliding mode. The performance of the proposed scheme, in two significant applications of the multiple robot arms, is validated through numerical simulations.

  2. Unequal-period combination approach of gray code and phase-shifting for 3-D visual measurement

    Science.gov (United States)

    Yu, Shuang; Zhang, Jing; Yu, Xiaoyang; Sun, Xiaoming; Wu, Haibin

    2016-09-01

    Combination of Gray code and phase-shifting is the most practical and advanced approach for the structured light 3-D measurement so far, which is able to measure objects with complex and discontinuous surface. However, for the traditional combination of the Gray code and phase-shifting, the captured Gray code images are not always sharp cut-off in the black-white conversion boundaries, which may lead to wrong decoding analog code orders. Moreover, during the actual measurement, there also exists local decoding error for the wrapped analog code obtained with the phase-shifting approach. Therefore, for the traditional approach, the wrong analog code orders and the local decoding errors will consequently introduce the errors which are equivalent to a fringe period when the analog code is unwrapped. In order to avoid one-fringe period errors, we propose an approach which combines Gray code with phase-shifting according to unequal period. With theoretical analysis, we build the measurement model of the proposed approach, determine the applicable condition and optimize the Gray code encoding period and phase-shifting fringe period. The experimental results verify that the proposed approach can offer a reliable unwrapped analog code, which can be used in 3-D shape measurement.

  3. Fountain code-based error control scheme for dimmable visible light communication systems

    Science.gov (United States)

    Feng, Lifang; Hu, Rose Qingyang; Wang, Jianping; Xu, Peng

    2015-07-01

    In this paper, a novel error control scheme using Fountain codes is proposed in on-off keying (OOK) based visible light communications (VLC) systems. By using Fountain codes, feedback information is needed to be sent back to the transmitter only when transmitted messages are successfully recovered. Therefore improved transmission efficiency, reduced protocol complexity and relative little wireless link-layer delay are gained. By employing scrambling techniques and complementing symbols, the least complemented symbols are needed to support arbitrary dimming target values, and the value of entropy of encoded message are increased.

  4. Performance of an Error Control System with Turbo Codes in Powerline Communications

    Directory of Open Access Journals (Sweden)

    Balbuena-Campuzano Carlos Alberto

    2014-07-01

    Full Text Available This paper reports the performance of turbo codes as an error control technique in PLC (Powerline Communications data transmissions. For this system, computer simulations are used for modeling data networks based on the model classified in technical literature as indoor, and uses OFDM (Orthogonal Frequency Division Multiplexing as a modulation technique. Taking into account the channel, modulation and turbo codes, we propose a methodology to minimize the bit error rate (BER, as a function of the average received signal noise ratio (SNR.

  5. A reaction-diffusion-based coding rate control mechanism for camera sensor networks.

    Science.gov (United States)

    Yamamoto, Hiroshi; Hyodo, Katsuya; Wakamiya, Naoki; Murata, Masayuki

    2010-01-01

    A wireless camera sensor network is useful for surveillance and monitoring for its visibility and easy deployment. However, it suffers from the limited capacity of wireless communication and a network is easily overflown with a considerable amount of video traffic. In this paper, we propose an autonomous video coding rate control mechanism where each camera sensor node can autonomously determine its coding rate in accordance with the location and velocity of target objects. For this purpose, we adopted a biological model, i.e., reaction-diffusion model, inspired by the similarity of biological spatial patterns and the spatial distribution of video coding rate. Through simulation and practical experiments, we verify the effectiveness of our proposal.

  6. On the Need of Novel Medium Access Control Schemes for Network Coding enabled Wireless Mesh Networks

    DEFF Research Database (Denmark)

    Paramanathan, Achuthan; Pahlevani, Peyman; Roetter, Daniel Enrique Lucani;

    2013-01-01

    This paper advocates for a new Medium Access Control (MAC) strategy for wireless meshed networks by identifying overload scenarios in order to provide additional channel access priority to the relay. The key behind our MAC protocol is that the relay will adjust its back off window size according...... to the incoming and outgoing packet ratio. We describe the new protocol as an extension to the CSMA/CA protocol and implement the protocol on our own hardware platform. By means of our own testbed, we investigate two basic network structures, namely, the two-way relay and the cross topology. It is well known...... that network coding will improve the throughput in such systems, but our novel medium access scheme improves the performance in the cross topology by another 66 % for network coding and 150 % for classical forwarding in theory. These gains translate in a theoretical gain of 33 % of network coding over...

  7. Industrial image processing visual quality control in manufacturing

    CERN Document Server

    Demant, Christian; Garnica, Carsten

    2013-01-01

    This practical introduction focuses on how to build integrated solutions to industrial vision problems from individual algorithms. It gives a hands-on guide for setting up automated visual inspection systems using the NeuroCheck software package.

  8. Visualization and Quality Control Web Tools for CERES Products

    Science.gov (United States)

    Mitrescu, C.; Doelling, D.; Chu, C.; Rutan, D. A.

    2015-12-01

    The CERES project continues to provide the scientific community a wide variety of satellite-derived data products such as observed TOA broadband shortwave and longwave observed fluxes, computed TOA and Surface fluxes, as well as cloud, aerosol, and other atmospheric parameters. These datasets encompass a wide range of temporal and spatial resolutions, suited to specific applications. Now in its 15-year, CERES products are mostly used by climate modeling communities that focus on global mean energetics, meridianal heat transport, and climate trend studies. However, CERES products are now beginning to be used by an even broader audience, like the green energy, health and environmental agencies. With its well-established web-oriented Ordering and Visualization Tool (OVT), CERES products are now much more assessable to users of all communities. The OVT Team introduced a series of specialized functions such as 1- and 2-D histogram, anomaly, deseasonalization, temporal and spatial averaging, side-by-side parameter comparison, and others that made the process of Quality Control far easier and faster. Over time increasingly higher order temporal and spatial resolution products are being made available to the public through the CERES OVT's web-pages. Moreover, ground site observed surface fluxes are being integrated into the OVT to facilitate the CERES project to QC the CERES computed surface fluxes. These features will give users the opportunity to perform their own comparisons of the CERES computed surface fluxes and observed ground site fluxes. An overview of the CERES OVT basic functions and its QC capabilities, new developments, as well as future steps in expanding its capabilities will be presented at the meeting.

  9. A New Region-of-interest Coding Method to Control the Relative Quality of Progressive Decoded Images

    Institute of Scientific and Technical Information of China (English)

    LI Ji-liang; FANG Xiang-zhong; ZHANG Dong-dong

    2007-01-01

    Based on the ideas of controlling relative quality and rearranging bitplanes, a new ROI coding method for JPEG2000 was proposed, which shifts and rearranges bitplanes in units of bitplane groups.It can code arbitrary shaped ROI without shape coding, and reserve almost arbitrary percent of background information.It also can control the relative quality of progressive decoded images.In addition, it is easy to be implemented and has low computational cost.

  10. Visual outcome, endocrine function and tumor control after fractionated stereotactic radiation therapy of craniopharyngiomas in adults

    DEFF Research Database (Denmark)

    Astradsson, Arnar; Munck Af Rosenschöld, Per; Feldt-Rasmussen, Ulla

    2017-01-01

    BACKGROUND: The purpose of this study was to examine visual outcome, endocrine function and tumor control in a prospective cohort of craniopharyngioma patients, treated with fractionated stereotactic radiation therapy (FSRT). MATERIAL AND METHODS: Sixteen adult patients with craniopharyngiomas were.......7-13.1) for visual outcome, endocrine function, and tumor control, respectively. RESULTS: Visual acuity impairment was present in 10 patients (62.5%) and visual field defects were present in 12 patients (75%) before FSRT. One patient developed radiation-induced optic neuropathy at seven years after FSRT. Thirteen...

  11. Automatic Activation of Phonological Code during Visual Word Recognition in Children: A Masked Priming Study in Grades 3 and 5

    Science.gov (United States)

    Sauval, Karinne; Perre, Laetitia; Casalis, Séverine

    2017-01-01

    The present study aimed to investigate the development of automatic phonological processes involved in visual word recognition during reading acquisition in French. A visual masked priming lexical decision experiment was carried out with third, fifth graders and adult skilled readers. Three different types of partial overlap between the prime and…

  12. Automatic Activation of Phonological Code during Visual Word Recognition in Children: A Masked Priming Study in Grades 3 and 5

    Science.gov (United States)

    Sauval, Karinne; Perre, Laetitia; Casalis, Séverine

    2017-01-01

    The present study aimed to investigate the development of automatic phonological processes involved in visual word recognition during reading acquisition in French. A visual masked priming lexical decision experiment was carried out with third, fifth graders and adult skilled readers. Three different types of partial overlap between the prime and…

  13. Characterization of Visual Scanning Patterns in Air Traffic Control

    Directory of Open Access Journals (Sweden)

    Sarah N. McClung

    2016-01-01

    Full Text Available Characterization of air traffic controllers’ (ATCs’ visual scanning strategies is a challenging issue due to the dynamic movement of multiple aircraft and increasing complexity of scanpaths (order of eye fixations and saccades over time. Additionally, terminologies and methods are lacking to accurately characterize the eye tracking data into simplified visual scanning strategies linguistically expressed by ATCs. As an intermediate step to automate the characterization classification process, we (1 defined and developed new concepts to systematically filter complex visual scanpaths into simpler and more manageable forms and (2 developed procedures to map visual scanpaths with linguistic inputs to reduce the human judgement bias during interrater agreement. The developed concepts and procedures were applied to investigating the visual scanpaths of expert ATCs using scenarios with different aircraft congestion levels. Furthermore, oculomotor trends were analyzed to identify the influence of aircraft congestion on scan time and number of comparisons among aircraft. The findings show that (1 the scanpaths filtered at the highest intensity led to more consistent mapping with the ATCs’ linguistic inputs, (2 the pattern classification occurrences differed between scenarios, and (3 increasing aircraft congestion caused increased scan times and aircraft pairwise comparisons. The results provide a foundation for better characterizing complex scanpaths in a dynamic task and automating the analysis process.

  14. Downlink power control in multi-code CDMA for mobile medicine.

    Science.gov (United States)

    Lin, Chin-Feng; Chang, Wen-Thong; Lee, Hsin-Wang; Hung, Shih-Ii

    2006-05-01

    In this paper, we propose a downlink power-control mechanism to be applied in a multi-code code division multiple access (CDMA) mobile medicine system. The mobile medicine system can provide (i) measured blood pressure and body temperature, (ii) medical signals measured by the electrocardiogram (ECG) device, (iii) mobile patient's history, (iv) G.729 audio signals, (v) Joint Photographic Experts Group 2000 Medical images and Moving Picture Experts Group 4 charge-coupled device sensor video signals. By utilizing a multi-code CDMA spread spectrum communication system with downlink power-control strategy, it is possible for this system to meet the quality of service requirements of a mobile medicine network. In addition, such a system can maximize the resource utilization. For different messages to be sent, the power is controlled according to the requisite bit error rate (BER). Higher transmission power is given to the media with lower BER requirement. Numerical analysis shows that the ratios of transmission power for voice, video, and data virtual channels is approximately 1:2:13 when the BERs for voice, video, and data are 10(wedge)(- 3), 10(wedge)(- 4), and 10(wedge)(- 7), respectively. This power ratio is similar to the ratio of signal-to-noise plus interference power ratio for voice, video, and data during transmission. For the purpose of verifying the proposed argument, a simulation has been done and the results match the derivation very well.

  15. Multi-rate control over AWGN channels via analog joint source-channel coding

    KAUST Repository

    Khina, Anatoly

    2017-01-05

    We consider the problem of controlling an unstable plant over an additive white Gaussian noise (AWGN) channel with a transmit power constraint, where the signaling rate of communication is larger than the sampling rate (for generating observations and applying control inputs) of the underlying plant. Such a situation is quite common since sampling is done at a rate that captures the dynamics of the plant and which is often much lower than the rate that can be communicated. This setting offers the opportunity of improving the system performance by employing multiple channel uses to convey a single message (output plant observation or control input). Common ways of doing so are through either repeating the message, or by quantizing it to a number of bits and then transmitting a channel coded version of the bits whose length is commensurate with the number of channel uses per sampled message. We argue that such “separated source and channel coding” can be suboptimal and propose to perform joint source-channel coding. Since the block length is short we obviate the need to go to the digital domain altogether and instead consider analog joint source-channel coding. For the case where the communication signaling rate is twice the sampling rate, we employ the Archimedean bi-spiral-based Shannon-Kotel\\'nikov analog maps to show significant improvement in stability margins and linear-quadratic Gaussian (LQG) costs over simple schemes that employ repetition.

  16. A controlled experiment for program comprehension through trace visualization

    NARCIS (Netherlands)

    Cornelissen, B.; Zaidman, A.

    2009-01-01

    Accepted version for publication in IEEE Transactions on Software Engineering. Software maintenance activities require a sufficient level of understanding of the software at hand that unfortunately is not always readily available. Execution trace visualization is a common approach in gaining this u

  17. Glocalized New Age Spirituality: A Mental Map of the New Central Bus Station in Tel Aviv, Deciphered through Its Visual Codes and Based on Ethno-Visual Research

    Science.gov (United States)

    Ben-Peshat, Malka; Sitton, Shoshana

    2011-01-01

    We present here the findings of an ethno-visual research study involving the creation of a mental map of images, artifacts and practices in Tel Aviv's New Central Bus Station. This huge and complex building, part bus station, part shopping mall, has become a stage for multicultural encounters and interactions among diverse communities of users.…

  18. Controlled quantum secure direct communication using a non-symmetric quantum channel with quantum superdense coding

    Energy Technology Data Exchange (ETDEWEB)

    Xia, Yan [School of Physic and Optoelectronic, Dalian University of Technology, Dalian 116024 (China)]. E-mail: xia-208@163.com; Song, He-Shan [School of Physic and Optoelectronic, Dalian University of Technology, Dalian 116024 (China)]. E-mail: hssong@dlut.edu.cn

    2007-04-23

    We present a controlled quantum secure direct communication protocol that uses a 2-dimensional Greenberger-Horne-Zeilinger (GHZ) entangled state and a 3-dimensional Bell-basis state and employs the high-dimensional quantum superdense coding, local collective unitary operations and entanglement swapping. The proposed protocol is secure and of high source capacity. It can effectively protect the communication against a destroying-travel-qubit-type attack. With this protocol, the information transmission is greatly increased. This protocol can also be modified, so that it can be used in a multi-party control system.

  19. Streaming and congestion control using scalable video coding based on H.264/AVC

    Institute of Scientific and Technical Information of China (English)

    NGUYEN Dieu Thanh; OSTERMANN Joern

    2006-01-01

    This paper presents a streaming system using scalable video coding based on H.264/AVC. The system provides a congestion control algorithm supported by channel bandwidth estimation of the client. It uses retransmission only for packets of the base layer to disburden the congested network. The bandwidth estimation allows for adjusting the transmission rate quickly to the current available bandwidth of the network. Compared to binomial congestion control, the proposed system allows for shorter start-up times and data rate adaptation. The paper describes the components of this streaming system and the results of experiments showing that the proposed approach works effectively for streaming video.

  20. Real-coded genetic algorithm for optimal vibration control of flexible structure

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Presents the study on the optimum location of actuators/sensors for active vibration control in aerospace flexible structures with the performance function first built by maximization of dissipation energy due to control action and a real-coded genetic algorithm then proposed to produce a global-optimum solution, and proves the feasibility and advantages of this algorithm with the example of a standard test function and a two-collocated actuators/sensors cantilever, and comparing the results with those given in the literatures.

  1. Preparing Content-Rich Learning Environments with VPython and Excel, Controlled by Visual Basic for Applications

    Science.gov (United States)

    Prayaga, Chandra

    2008-01-01

    A simple interface between VPython and Microsoft (MS) Office products such as Word and Excel, controlled by Visual Basic for Applications, is described. The interface allows the preparation of content-rich, interactive learning environments by taking advantage of the three-dimensional (3D) visualization capabilities of VPython and the GUI…

  2. Experimental study on the effects of visualized functionally abstracted information on process control tasks

    Energy Technology Data Exchange (ETDEWEB)

    Ham, Dong-Han [School of Computing Science, Middlesex University, The Burroughs London, London NW4 4BT (United Kingdom)], E-mail: d.ham@mdx.ac.uk; Yoon, Wan Chul [Department of Industrial Engineering, Korea Advanced Institute of Science and Technology, 373-1 Kusong-dong, Yusong-gu, Taejon 305-701 (Korea, Republic of); Han, Byoung-Tae [Global Consumer Group, Citibank Korea Inc., Shinmoon-ro, Chongro-gu, Seoul 110-762 (Korea, Republic of)

    2008-02-15

    Two distinct design problems of information display for process control are information content representation and visual form design. Regarding information content, we experimentally showed the effectiveness of functionally abstracted information without the benefits of sophisticated graphical presentation in various task situations. However, since it is obvious that the effects of the information display are also influenced by display formats (i.e., visual forms) as well as the information content, further research was required to investigate the effectiveness of visualized functionally abstracted information. For this purpose, this study conducted an experiment in complex process control tasks (operation and fault diagnosis). The experimental purposes were to confirm the effectiveness of the functionally abstracted information visualized with emergent features or peculiar geometric forms and to examine the additional effects of the visualization on task performance. The results showed that functionally abstracted information presented with sophisticated visual forms helped operators perform process control tasks in more efficient and safe way. The results also indicated the importance of explicit visualization of goal-means relation between higher and lower abstraction levels. Lastly, this study proposed a framework for designing visual forms for process control display.

  3. The Impact of Baseline Trend Control on Visual Analysis of Single-Case Data

    Science.gov (United States)

    Mercer, Sterett H.; Sterling, Heather E.

    2012-01-01

    The impact of baseline trend control on visual analyses of AB intervention graphs was examined with simulated data at various values of baseline trend, autocorrelation, and effect size. Participants included 202 undergraduate students with minimal training in visual analysis and 10 graduate students and faculty with more training and experience in…

  4. Effects of visual feedback therapy on postural control in bilateral standing after stroke: a systematic review.

    NARCIS (Netherlands)

    Peppen, R.P. van; Kortsmit, M.; Lindeman, E.; Kwakkel, G.

    2006-01-01

    OBJECTIVE: To establish whether bilateral standing with visual feedback therapy after stroke improves postural control compared with conventional therapy and to evaluate the generalization of the effects of visual feedback therapy on gait and gait-related activities. DESIGN: A systematic review. MET

  5. Field-programmable beam reconfiguring based on digitally-controlled coding metasurface

    Science.gov (United States)

    Wan, Xiang; Qi, Mei Qing; Chen, Tian Yi; Cui, Tie Jun

    2016-01-01

    Digital phase shifters have been applied in traditional phased array antennas to realize beam steering. However, the phase shifter deals with the phase of the induced current; hence, it has to be in the path of each element of the antenna array, making the phased array antennas very expensive. Metamaterials and/or metasurfaces enable the direct modulation of electromagnetic waves by designing subwavelength structures, which opens a new way to control the beam scanning. Here, we present a direct digital mechanism to control the scattered electromagnetic waves using coding metasurface, in which each unit cell loads a pin diode to produce binary coding states of “1” and “0”. Through data lines, the instant communications are established between the coding metasurface and the internal memory of field-programmable gate arrays (FPGA). Thus, we realize the digital modulation of electromagnetic waves, from which we present the field-programmable reflective antenna with good measurement performance. The proposed mechanism and functional device have great application potential in new-concept radar and communication systems. PMID:26861110

  6. An Improved Scheme of QR Code Based on Visual Crypotography%基于可视密码的改进 QR 码方案

    Institute of Scientific and Technical Information of China (English)

    张舒; 李凌

    2015-01-01

    QR码在二维码技术中最具代表性,目前广泛应用于电子票务领域。论文针对QR码无法保证用户个人信息的安全问题,利用可视密码技术,采用基于异或(XOR)运算的(2,2)可视密码方案,易于操作且提高了 QR 码的安全性与可靠性。%QR code is widely used in Electronic ticketing which belongs to one of the two‐dimensional code .In order to solve the security issues of protected information of QR Code ,visual cryptography technology is introduced .A (2 ,2) VCS with XOR algorithm what used in this paper is simple to decrypt and the safety and reliability of QR Code has been im‐proved .

  7. Combined Wavelet Video Coding and Error Control for Internet Streaming and Multicast

    Directory of Open Access Journals (Sweden)

    Tianli Chu

    2003-01-01

    Full Text Available This paper proposes an integrated approach to Internet video streaming and multicast (e.g., receiver-driven layered multicast (RLM by McCanne based on combined wavelet video coding and error control. We design a packetized wavelet video (PWV coder to facilitate its integration with error control. The PWV coder produces packetized layered bitstreams that are independent among layers while being embedded within each layer. Thus, a lost packet only renders the following packets in the same layer useless. Based on the PWV coder, we search for a multilayered error-control strategy that optimally trades off source and channel coding for each layer under a given transmission rate to mitigate the effects of packet loss. While both the PWV coder and the error-control strategy are new—the former incorporates embedded wavelet video coding and packetization and the latter extends the single-layered approach for RLM by Chou et al.—the main distinction of this paper lies in the seamless integration of the two parts. Theoretical analysis shows a gain of up to 1 dB on a channel with 20% packet loss using our combined approach over separate designs of the source coder and the error-control mechanism. This is also substantiated by our simulations with a gain of up to 0.6 dB. In addition, our simulations show a gain of up to 2.2 dB over previous results reported by Chou et al.

  8. Improving Code Quality of the Compact Muon Solenoid Electromagnetic Calorimeter Control Software to Increase System Maintainability

    CERN Multimedia

    Holme, Oliver; Dissertori, Günther; Djambazov, Lubomir; Lustermann, Werner; Zelepoukine, Serguei

    2013-01-01

    The Detector Control System (DCS) software of the Electromagnetic Calorimeter (ECAL) of the Compact Muon Solenoid (CMS) experiment at CERN is designed primarily to enable safe and efficient operation of the detector during Large Hadron Collider (LHC) data-taking periods. Through a manual analysis of the code and the adoption of ConQAT [1], a software quality assessment toolkit, the CMS ECAL DCS team has made significant progress in reducing complexity and improving code quality, with observable results in terms of a reduction in the effort dedicated to software maintenance. This paper explains the methodology followed, including the motivation to adopt ConQAT, the specific details of how this toolkit was used and the outcomes that have been achieved. [1] ConQAT, Continuous Quality Assessment Toolkit; https://www.conqat.org/

  9. Design and Control of a Ferromagnetic Coded Micro-Carrier Biochip Sensor for Multiplex Detection of Antibodies

    Directory of Open Access Journals (Sweden)

    Rong-Seng Chang

    2011-08-01

    Full Text Available This paper describes a method for producing a novel type of ferromagnetic coded micro-carrier. The ferromagnetic coded micro-carriers are about 200 μm in length, 200 μm in width and 50 μm in thickness, and contain eight code elements with two distinguishable codes (hollow and solid, allowing for 28 unique codes. The code shapes include rectangle, circle, etc. Differently shaped coded micro-carriers could carry different antigens for detection of its complementary antibody. These many shapes of coded micro-carriers would be used simultaneously allowing us to make multiple detections for different antibodies at the same time. A molding process is applied for fabrication of the ferromagnetically coded micro-carriers where Fe material (Fe powder mixed with binder is shaped in many tiny molds to produce the coded shapes used for identification of the bio-molecules. Magnetic force is used to control the movement and location of the ferromagnetic coded micro-carriers to prevent the loss during the hybridization process. The results of image process and analysis system testing are satisfactory. The results of our micro-carrier detection system for two sets of R and B color analysis are proportional to those obtained from ELISA antibody detection.

  10. Statistical and Variational Methods for Problems in Visual Control

    Science.gov (United States)

    2009-03-02

    invariant visual tracking by particle filtering" (with A. Nakhmani), SPIE, 2008. 81. "Adaptive Bayesian shrinkage model for spherical wavelet based denoising ...vision. In recent work, we have described a random particle system, evolving on the discretized unit circle, whose profile converges toward the Gauss...34). Specifically, we have chosen to smooth by evolving P° according to a discretized version of the partial differential equation r apt -^ = {{P$)2PL

  11. Scene perception and the visual control of travel direction in navigating wood ants

    Science.gov (United States)

    Collett, Thomas S.; Lent, David D.; Graham, Paul

    2014-01-01

    This review reflects a few of Mike Land's many and varied contributions to visual science. In it, we show for wood ants, as Mike has done for a variety of animals, including readers of this piece, what can be learnt from a detailed analysis of an animal's visually guided eye, head or body movements. In the case of wood ants, close examination of their body movements, as they follow visually guided routes, is starting to reveal how they perceive and respond to their visual world and negotiate a path within it. We describe first some of the mechanisms that underlie the visual control of their paths, emphasizing that vision is not the ant's only sense. In the second part, we discuss how remembered local shape-dependent and global shape-independent features of a visual scene may interact in guiding the ant's path. PMID:24395962

  12. Transient control of grid-connected converters for wind turbines to fulfill emerging grid codes

    Energy Technology Data Exchange (ETDEWEB)

    Tong, Dan; Yuan, Xiaoming; Hu, Jiabing [Huazhong Univ. of Science and Technology, Wuhan (China). State Key Laboratory of Advanced Electromagnetic Engineering and Technology

    2012-07-01

    This paper studies the controllability of grid-connected converters for wind turbines during symmetrical grid faults. Voltage phase jump often occurs at transient faults. If the phase-locked loop (PLL) fails to capture the voltage phase immediately, wind turbines can not control active and reactive power quickly, and even be damaged, especially for DFIG-based wind turbines. This paper proposes a dynamic reference frame, which helps the controller of the grid-connected converter be oriented to the grid voltage vector immediately. Taking the full-capacity wind turbine as an example, feasibility of the dynamic reference frame is analyzed in detail. Simulation results show that wind turbines can output controllable power quickly with the dynamic reference frame employed, which fulfills emerging grid codes. (orig.)

  13. Calibration plot for proteomics: A graphical tool to visually check the assumptions underlying FDR control in quantitative experiments.

    Science.gov (United States)

    Giai Gianetto, Quentin; Combes, Florence; Ramus, Claire; Bruley, Christophe; Couté, Yohann; Burger, Thomas

    2016-01-01

    In MS-based quantitative proteomics, the FDR control (i.e. the limitation of the number of proteins that are wrongly claimed as differentially abundant between several conditions) is a major postanalysis step. It is classically achieved thanks to a specific statistical procedure that computes the adjusted p-values of the putative differentially abundant proteins. Unfortunately, such adjustment is conservative only if the p-values are well-calibrated; the false discovery control being spuriously underestimated otherwise. However, well-calibration is a property that can be violated in some practical cases. To overcome this limitation, we propose a graphical method to straightforwardly and visually assess the p-value well-calibration, as well as the R codes to embed it in any pipeline. All MS data have been deposited in the ProteomeXchange with identifier PXD002370 (http://proteomecentral.proteomexchange.org/dataset/PXD002370).

  14. Experimental System for Investigation of Visual Sensory Input in Postural Feedback Control

    Directory of Open Access Journals (Sweden)

    Jozef Pucik

    2012-01-01

    Full Text Available The human postural control system represents a biological feedback system responsible for maintenance of upright stance. Vestibular, proprioceptive and visual sensory inputs provide the most important information into the control system, which controls body centre of mass (COM in order to stabilize the human body resembling an inverted pendulum. The COM can be measured indirectly by means of a force plate as the centre of pressure (COP. Clinically used measurement method is referred to as posturography. In this paper, the conventional static posturography is extended by visual stimulation, which provides insight into a role of visual information in balance control. Visual stimuli have been designed to induce body sway in four specific directions – forward, backward, left and right. Stabilograms were measured using proposed single-PC based system and processed to calculate velocity waveforms and posturographic parameters. The parameters extracted from pre-stimulus and on-stimulus periods exhibit statistically significant differences.

  15. Relationship between writing skills and visual-motor control in low-vision students.

    Science.gov (United States)

    Atasavun Uysal, Songül; Aki, Esra

    2012-08-01

    The purpose of this study was to investigate the relationship between handwriting skills and visual motor control among students with low vision and to compare this with the performance of their normal sighted peers. 42 students with low vision and 26 normal sighted peers participated. The Bruininks-Oseretsky Motor Proficiency Test-Short Form (BOTMP-SF), Jebsen Taylor Hand Function Test's writing subtest, and a legibility assessment were administered. Significant differences were found between groups for students' writing speed, legibility, and visual motor control. Visual motor control was correlated both writing speed and legibility. Students with low vision had poorer handwriting performance, with lower legibility and slower writing speed. Writing performance time was related to visual motor control in students with low vision.

  16. Visual Problem Solving and Self‐regulation in Training Air Traffic Control

    NARCIS (Netherlands)

    Meeuwen van, Ludo

    2015-01-01

    Van Meeuwen, L. W. (2013). Visual problem solving and self-regulation in training air traffic control (Unpublished doctoral dissertation). Centre for Learning Sciences and Technologies, Open Universiteit, Heerlen, The Netherlands.

  17. Visual problem solving and self-regulation in training air traffic control

    NARCIS (Netherlands)

    Van Meeuwen, Ludo

    2013-01-01

    Van Meeuwen, L. W. (2013). Visual problem solving and self-regulation in training air traffic control (Unpublished doctoral dissertation). Centre for Learning Sciences and Technologies, Open Universiteit, Heerlen, The Netherlands.

  18. Visual problem solving and self-regulation in training air traffic control

    NARCIS (Netherlands)

    Van Meeuwen, Ludo

    2013-01-01

    Van Meeuwen, L. W. (2013). Visual problem solving and self-regulation in training air traffic control (Unpublished doctoral dissertation). Centre for Learning Sciences and Technologies, Open Universiteit, Heerlen, The Netherlands.

  19. Visual Problem Solving and Self‐regulation in Training Air Traffic Control

    NARCIS (Netherlands)

    Meeuwen van, Ludo

    2015-01-01

    Van Meeuwen, L. W. (2013). Visual problem solving and self-regulation in training air traffic control (Unpublished doctoral dissertation). Centre for Learning Sciences and Technologies, Open Universiteit, Heerlen, The Netherlands.

  20. On-line and Model-based Approaches to the Visual Control of Action

    OpenAIRE

    Zhao, Huaiyong; Warren, William H.

    2014-01-01

    Two general approaches to the visual control of action have emerged in last few decades, known as the on-line and model-based approaches. The key difference between them is whether action is controlled by current visual information or on the basis of an internal world model. In this paper, we evaluate three hypotheses: strong on-line control, strong model-based control, and a hybrid solution that combines on-line control with weak off-line strategies. We review experimental research on the co...

  1. Transcription of the non-coding RNA upperhand controls Hand2 expression and heart development

    Science.gov (United States)

    Anderson, Kelly M.; Anderson, Douglas M.; McAnally, John R.; Shelton, John M.; Bassel-Duby, Rhonda; Olson, Eric N.

    2017-01-01

    HAND2 is an ancestral regulator of heart development and one of four transcription factors that control the reprogramming of fibroblasts into cardiomyocytes1–4. Deletion of Hand2 in mice results in right ventricle hypoplasia and embryonic lethality1,5. Hand2 expression is tightly regulated by upstream enhancers6,7 that reside within a super-enhancer delineated by histone H3 acetyl Lys27 (H3K27ac) modifications8. Here we show that transcription of a Hand2-associated long non-coding RNA, which we named upperhand (Uph), is required to maintain the super-enhancer signature and elongation of RNA polymerase II through the Hand2 enhancer locus. Blockade of Uph transcription, but not knockdown of the mature transcript, abolished Hand2 expression, causing right ventricular hypoplasia and embryonic lethality in mice. Given the substantial number of uncharacterized promoter-associated long non-coding RNAs encoded by the mammalian genome9, the Uph–Hand2 regulatory partnership offers a mechanism by which divergent non-coding transcription can establish a permissive chromatin environment. PMID:27783597

  2. X-ray simulation with the Monte Carlo code PENELOPE. Application to Quality Control.

    Science.gov (United States)

    Pozuelo, F; Gallardo, S; Querol, A; Verdú, G; Ródenas, J

    2012-01-01

    A realistic knowledge of the energy spectrum is very important in Quality Control (QC) of X-ray tubes in order to reduce dose to patients. However, due to the implicit difficulties to measure the X-ray spectrum accurately, it is not normally obtained in routine QC. Instead, some parameters are measured and/or calculated. PENELOPE and MCNP5 codes, based on the Monte Carlo method, can be used as complementary tools to verify parameters measured in QC. These codes allow estimating Bremsstrahlung and characteristic lines from the anode taking into account specific characteristics of equipment. They have been applied to simulate an X-ray spectrum. Results are compared with theoretical IPEM 78 spectrum. A sensitivity analysis has been developed to estimate the influence on simulated spectra of important parameters used in simulation codes. With this analysis it has been obtained that the FORCE factor is the most important parameter in PENELOPE simulations. FORCE factor, which is a variance reduction method, improves the simulation but produces hard increases of computer time. The value of FORCE should be optimized so that a good agreement of simulated and theoretical spectra is reached, but with a reduction of computer time. Quality parameters such as Half Value Layer (HVL) can be obtained with the PENELOPE model developed, but FORCE takes such a high value that computer time is hardly increased. On the other hand, depth dose assessment can be achieved with acceptable results for small values of FORCE.

  3. GOTHIC: Gravitational oct-tree code accelerated by hierarchical time step controlling

    Science.gov (United States)

    Miki, Yohei; Umemura, Masayuki

    2017-04-01

    The tree method is a widely implemented algorithm for collisionless N-body simulations in astrophysics well suited for GPU(s). Adopting hierarchical time stepping can accelerate N-body simulations; however, it is infrequently implemented and its potential remains untested in GPU implementations. We have developed a Gravitational Oct-Tree code accelerated by HIerarchical time step Controlling named GOTHIC, which adopts both the tree method and the hierarchical time step. The code adopts some adaptive optimizations by monitoring the execution time of each function on-the-fly and minimizes the time-to-solution by balancing the measured time of multiple functions. Results of performance measurements with realistic particle distribution performed on NVIDIA Tesla M2090, K20X, and GeForce GTX TITAN X, which are representative GPUs of the Fermi, Kepler, and Maxwell generation of GPUs, show that the hierarchical time step achieves a speedup by a factor of around 3-5 times compared to the shared time step. The measured elapsed time per step of GOTHIC is 0.30 s or 0.44 s on GTX TITAN X when the particle distribution represents the Andromeda galaxy or the NFW sphere, respectively, with 224 = 16,777,216 particles. The averaged performance of the code corresponds to 10-30% of the theoretical single precision peak performance of the GPU.

  4. Transcription of the non-coding RNA upperhand controls Hand2 expression and heart development.

    Science.gov (United States)

    Anderson, Kelly M; Anderson, Douglas M; McAnally, John R; Shelton, John M; Bassel-Duby, Rhonda; Olson, Eric N

    2016-11-17

    HAND2 is an ancestral regulator of heart development and one of four transcription factors that control the reprogramming of fibroblasts into cardiomyocytes. Deletion of Hand2 in mice results in right ventricle hypoplasia and embryonic lethality. Hand2 expression is tightly regulated by upstream enhancers that reside within a super-enhancer delineated by histone H3 acetyl Lys27 (H3K27ac) modifications. Here we show that transcription of a Hand2-associated long non-coding RNA, which we named upperhand (Uph), is required to maintain the super-enhancer signature and elongation of RNA polymerase II through the Hand2 enhancer locus. Blockade of Uph transcription, but not knockdown of the mature transcript, abolished Hand2 expression, causing right ventricular hypoplasia and embryonic lethality in mice. Given the substantial number of uncharacterized promoter-associated long non-coding RNAs encoded by the mammalian genome, the Uph-Hand2 regulatory partnership offers a mechanism by which divergent non-coding transcription can establish a permissive chromatin environment.

  5. 基于Visual Basic 6.0的文件加/解密方法%Coding/Decoding a File Using Visual Basic 6.0

    Institute of Scientific and Technical Information of China (English)

    白桂梅; 朱乃立

    2003-01-01

    Visual Basic 6.0提供了强有力的文件、路径操作,在程序中能够实现文件的查找、读写以及删除,借助于二进制方式读写文件(属于传统文件I/O方式),可以对任何类型的文件进行加密,解密则是用加密时的密钥再次运行程序.

  6. Coding technology of PDF417 two-dimensional bar code and its implementation in Visual Basic%PDF417二维条码的编码技术及其在Visual Basic下的实现

    Institute of Scientific and Technical Information of China (English)

    孙静; 陈伟

    2005-01-01

    应用Visual Basic对PDF417条码进行了编码.针对编码模块的不同算法,提出了关于编码溢出、汉字编码等问题的讨论及解决方法.从而实现了PDF417编码程序在信息录入中的应用,并取得了良好的效果.

  7. Using a visual programming language to bridge the cognitive gap between a novice's mental model and program code

    Science.gov (United States)

    Smith, Bryan J.

    Current research suggests that many students do not know how to program very well at the conclusion of their introductory programming course. We believe that a reason novices have such difficulties learning programming is because engineering novices often learn through a lecture format where someone with programming knowledge lectures to novices, the novices attempt to absorb the content, and then reproduce it during exams. By primarily appealing to programming novices who prefer to understand visually, we research whether programming novices understand programming better if computer science concepts are presented using a visual programming language than if these programs are presented using a text-based programming language. This method builds upon previous research that suggests that most engineering students are visual learners, and we propose that using a flow-based visual programming language will address some of the most important and difficult topics to novices of programming. We use an existing flow-model tool, RAPTOR, to test this method, and share the program understanding results using this theory.

  8. Role of Visual Dysfunction in Postural Control in Children With Cerebral Palsy

    Directory of Open Access Journals (Sweden)

    G. Porro

    2005-01-01

    Full Text Available Introduction: Deficient postural control is one of the key problems in cerebral palsy (CP. Little, however, is known about the specific nature of postural problems of children with CP, nor of the relation between abnormal posture and dysfunction of the visual system. Aim of the study: To provide additional information on the association of abnormalities in postural control and visual dysfunction of the anterior or posterior part of the visual system. Methods: Data resulting from ophthalmologic, orthoptic, neurological, neuro-radiological, and ethological investigations of more than 313 neurologically impaired children were retrospectively analyzed. Results: Abnormal postural control related to ocular and ocular motor disorders consisted of anomalous head control and subsequent abnormal head posture and torticollis. The abnormal postural control related to retrochiasmatical damage of the visual system consisted of a torticollis combined with adjustment of the upper part of the body, as if at the same time adapting to a combination of defects and optimizing residual visual functions. Conclusion: Visual dysfunctions play a distinct role in the postural control of children with CP.

  9. Temporal and spatial trends in prey composition of wahoo Acanthocybium solandri: a diet analysis from the central North Pacific Ocean using visual and DNA bar-coding techniques.

    Science.gov (United States)

    Oyafuso, Z S; Toonen, R J; Franklin, E C

    2016-04-01

    A diet analysis was conducted on 444 wahoo Acanthocybium solandri caught in the central North Pacific Ocean longline fishery and a nearshore troll fishery surrounding the Hawaiian Islands from June to December 2014. In addition to traditional observational methods of stomach contents, a DNA bar-coding approach was integrated into the analysis by sequencing the cytochrome c oxidase subunit 1 (COI) region of the mtDNA genome to taxonomically identify individual prey items that could not be classified visually to species. For nearshore-caught A. solandri, juvenile pre-settlement reef fish species from various families dominated the prey composition during the summer months, followed primarily by Carangidae in autumn months. Gempylidae, Echeneidae and Scombridae were dominant prey taxa from the offshore fishery. Molidae was a common prey family found in stomachs collected north-east of the Hawaiian Archipelago while tetraodontiform reef fishes, known to have extended pelagic stages, were prominent prey items south-west of the Hawaiian Islands. The diet composition of A. solandri was indicative of an adaptive feeder and thus revealed dominant geographic and seasonal abundances of certain taxa from various ecosystems in the marine environment. The addition of molecular bar-coding to the traditional visual method of prey identifications allowed for a more comprehensive range of the prey field of A. solandri to be identified and should be used as a standard component in future diet studies.

  10. Improving reliability of non-volatile memory technologies through circuit level techniques and error control coding

    Science.gov (United States)

    Yang, Chengen; Emre, Yunus; Cao, Yu; Chakrabarti, Chaitali

    2012-12-01

    Non-volatile resistive memories, such as phase-change RAM (PRAM) and spin transfer torque RAM (STT-RAM), have emerged as promising candidates because of their fast read access, high storage density, and very low standby power. Unfortunately, in scaled technologies, high storage density comes at a price of lower reliability. In this article, we first study in detail the causes of errors for PRAM and STT-RAM. We see that while for multi-level cell (MLC) PRAM, the errors are due to resistance drift, in STT-RAM they are due to process variations and variations in the device geometry. We develop error models to capture these effects and propose techniques based on tuning of circuit level parameters to mitigate some of these errors. Unfortunately for reliable memory operation, only circuit-level techniques are not sufficient and so we propose error control coding (ECC) techniques that can be used on top of circuit-level techniques. We show that for STT-RAM, a combination of voltage boosting and write pulse width adjustment at the circuit-level followed by a BCH-based ECC scheme can reduce the block failure rate (BFR) to 10-8. For MLC-PRAM, a combination of threshold resistance tuning and BCH-based product code ECC scheme can achieve the same target BFR of 10-8. The product code scheme is flexible; it allows migration to a stronger code to guarantee the same target BFR when the raw bit error rate increases with increase in the number of programming cycles.

  11. Detection and reconstruction of error control codes for engineered and biological regulatory systems.

    Energy Technology Data Exchange (ETDEWEB)

    May, Elebeoba Eni; Rintoul, Mark Daniel; Johnston, Anna Marie; Pryor, Richard J.; Hart, William Eugene; Watson, Jean-Paul

    2003-10-01

    determining similar parameters for a received, noisy, error-control encoded data set. In addition to these goals, we initiated exploration of algorithmic approaches to determine if a data set could be approximated with an error-control code and performed initial investigations into optimization based methodologies for extracting the encoding algorithm given the coding rate of an encoded noise-free and noisy data stream.

  12. LOW COMPLEXITY LMMSE TURBO EQUALIZATION FOR COMBINED ERROR CONTROL CODED AND LINEARLY PRECODED OFDM

    Institute of Scientific and Technical Information of China (English)

    Qu Daiming; Zhu Guangxi

    2006-01-01

    The turbo equalization approach is studied for Orthogonal Frequency Division Multiplexing (OFDM) system with combined error control coding and linear precoding. While previous literatures employed linear precoder of small size for complexity reasons, this paper proposes to use a linear precoder of size larger than or equal to the maximum length of the equivalent discrete-time channel in order to achieve full frequency diversity and reduce complexities of the error control coder/decoder. Also a low complexity Linear Minimum Mean Square Error (LMMSE) turbo equalizer is derived for the receiver. Through simulation and performance analysis, it is shown that the performance of the proposed scheme over frequency selective fading channel reaches the matched filter bound; compared with the same coded OFDM without linear precoding, the proposed scheme shows an Signal-to-Noise Ratio (SNR) improvement of at least 6dB at a bit error rate of 10-6 over a multipath channel with exponential power delay profile. Convergence behavior of the proposed scheme with turbo equalization using various type of linear precoder/transformer, various interleaver size and error control coder of various constraint length is also investigated.

  13. Visual-Motor Control of Steering and Awareness of Performance

    Directory of Open Access Journals (Sweden)

    Callum Mole

    2012-05-01

    Full Text Available In order to carry out skilled, visually guided actions, humans need to be able to use feedback to monitor and adjust performance. Such feedback can be relatively low level, with some motor commands being recalibrated rapidly based on visual feedback with little cognitive awareness (eg, Mon-Williams and Murray 2000. In tasks such as driving, however, awareness of performance could be important for making strategic adjustments in order to respond to road conditions. To investigate whether participants could accurately gauge steering performance, we used a simulated driving scenario. Participants (n=30 were required to steer around a series of bends and stay within a central marked zone. In order to alter the task demands, the speed of travel (fast/slow and the width of the zone (narrow/wide were manipulated. After each bend the participants made an explicit percentage judgment of time spent within the required zone. The mean group steering results showed that performance was worst for faster speeds and narrower zones, and this pattern was matched in the awareness judgements. Closer inspection of the data, however, showed that at an individual level these judgements often failed to capture trial performance and were often merely influenced by the visible task characteristics (eg, fast and narrow trial. This suggests that participants may erroneously rely on salient cues about task characteristics to assess performance if direct feedback is weak. This has important implications for driving since individuals may be failing to respond to situation characteristics that actually make performance worse.

  14. 视知觉条件下步态运动的神经编码综述%A review of neural coding of gait movement under visual perception

    Institute of Scientific and Technical Information of China (English)

    朱凤云; 王如彬; 潘晓川

    2016-01-01

    神经编码理论的研究,对于了解大脑内部工作机制以及对于人工智能、脑-机接口等技术的应用前景都具有重要意义。通过分析目前常用的几种视知觉神经编码的原理、方法,评价它们各自的优缺点,发现无论是单个神经元层次上还是多个神经元层次上,甚至是网络层次上的编码方式,由于神经元之间复杂的非线性耦合方式,用计算模型来描述视知觉功能都存在一定的困难。基于这样一种研究现状,进一步分析了一种新的简单有效的编码方式-神经能量编码,此编码与现有的其他编码相互结合,有望解决原有编码所无法解决或无法解释的问题。在应用方面介绍了视知觉条件下的步态运动输出控制,分析讨论了目前人体步态运动控制的原理、研究方法及其面临的挑战。%Studying the neural code theory has an important significance for understanding human's brain working mechanism and practical application prospects of artificial intelligence or brain-computer interface.Through analyzing principles and methods of several current used neural codes of visual perception,and evaluating their advantages and disadvantages,it was found that there are certain difficulties for using computational model to demonstrate visual perception,whether the code pattern is at a single neuron level or at multiple neurons level,even at the network level, since the nonlinear couplings among neurons are complicated.Trying to solve these difficulties,a new simple but efficient coding theory called the neural energy code was analyzed further.It was hopeful that the existing coding theories are combined with the neural energy coding theory to solve the problems which the original codes cannot manage or explain. For applications,the gait motion output controlling under visual perception was discussed including its principles,studying methods and great challenges encountered in

  15. Distributed Video Coding: Iterative Improvements

    DEFF Research Database (Denmark)

    Luong, Huynh Van

    Nowadays, emerging applications such as wireless visual sensor networks and wireless video surveillance are requiring lightweight video encoding with high coding efficiency and error-resilience. Distributed Video Coding (DVC) is a new coding paradigm which exploits the source statistics...

  16. Preliminary Drop Time Analysis of a Control Rod Using CFD Code

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Myoung Hwan; Park, Jin Seok; Lee, Won Jae [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Park, Jun Hong [SEST Co., Seoul (Korea, Republic of)

    2010-05-15

    A control rod drive mechanism (CRDM) is a reactor regulating system, which can insert and withdraw a control rod containing a neutron absorbing material to control the reactivity of the reactor core. The latch type CRDM for the SMART (System-integrated Modular Advanced ReacTor) is going to be used. The drop time of the control rod in the design stage is one of important parameters for a safety analysis of the reactor. When the control rod is falling down into the core, it is retarded by various forces acting on it such as fluid resistance buoyancy and mechanical friction caused by contacting the inner surface of the guide thimble, etc.. However, complicated coupling of the various forces makes it difficult to predict the drop behavior. This paper describes the development of the 3D CFD analysis model using a FLUENT code. The single control rod of the Westinghouse 17x17 type optimized fuel assembly (W-OFA) was considered for the verification of the CFD model. A preliminary drop time analysis for the SMART with the simulated control rod was performed

  17. Cerebral aneurysm treatment using flow-diverting stents: in-vivo visualization of flow alterations by parametric colour coding to predict aneurysmal occlusion: preliminary results.

    Science.gov (United States)

    Gölitz, Philipp; Struffert, Tobias; Rösch, Julie; Ganslandt, Oliver; Knossalla, Frauke; Doerfler, Arnd

    2015-02-01

    After deployment of flow-diverting stents (FDS), complete aneurysm occlusion is not predictable. This study investigated whether parametric colour coding (PCC) could allow in vivo visualization of flow alterations induced by FDS and identify favourable or adverse flow modulations. Thirty-six patients treated by FDS were analyzed. Preinterventional and postinterventional DSA-series were postprocessed by PCC and time-density curves (TDCs) were calculated. The parameters aneurysmal inflow, outflow, and relative time-to-peak (rTTP) were calculated. Preinterventional and postinterventional values were compared and related to occlusion rate. Postinterventional inflow showed a mean reduction of 37%, outflow of 51%, and rTTP a prolongation of 82%. Saccular aneurysm occlusion occurred if a reduction of at least 15% was achieved for inflow and 35% for outflow (sensitivity: 89%, specificity: 82%). Unchanged outflow and a slightly prolonged rTTP were associated with growth in one fusiform aneurysm. PCC allows visualization of flow alterations after FDS treatment, illustrating "flow diverting effects" by the TDC shape and indicating mainly aneurysmal outflow and lesser inflow changes. Quantifiable parameters (inflow, outflow, rTTP) can be obtained, thresholds for predicting aneurysm occlusion determined, and adverse flow modulations assumed. As a rapid intraprocedural tool, PCC might support the decision to implant more than one FDS. • After deployment of a flow-diverting stent, complete aneurysm occlusion is unpredictable. • Parametric colour coding offers new options for visualizing in vivo flow alterations non-invasively. • Quantifiable parameters, i.e., aneurysmal inflow/outflow can be obtained allowing prognostic stratification. • Rapid, intraprocedural application allows treatment monitoring, potentially contributing to patient safety.

  18. Vibrational circular dichroism analysis reveals a conformational change of the baccatin III ring of paclitaxel: visualization of conformations using a new code for structure-activity relationships.

    Science.gov (United States)

    Izumi, Hiroshi; Ogata, Atsushi; Nafie, Laurence A; Dukor, Rina K

    2008-03-21

    The comparison between measured and conformer-weighted calculated VCD spectra of the baccatin III ring of paclitaxel and visualization of the conformations using the new code for structure-activity relationships are reported for the first time. The VCD spectrum of paclitaxel closely resembles that of the baccatin III ring. The large characteristic nuCO VCD bands with bisignate signs (1732 cm-1, Deltaepsilon = -1.6 x 10(-1); 1715 cm(-1), Deltaepsilon = 2.4 x 10(-1)) strongly reflect the structural property of the family of conformations bacc-ABC32F defined using the new code. The comparison with the conformation of the baccatin III core in the electron micrograph of the crystal structure of tubulin-paclitaxel (1JFF) suggests a conformational change of paclitaxel corresponding to a switch through the binding with beta-tublin and the intermolecular interactions involving the hydroxyl group (D) and carbonyl of acetoxy group (E). The representation of conformational codes allows complicated conformations to be very easily compared and facilitates future computational analyses such as those for the large-molecule calculations as well as genome analysis.

  19. Effect of visual biofeedback to acquire supraglottic swallow in healthy individuals: a randomized-controlled trial.

    Science.gov (United States)

    Imada, Miho; Kagaya, Hitoshi; Ishiguro, Yuriko; Kato, Miho; Inamoto, Yoko; Tanaka, Takashi; Shibata, Seiko; Saitoh, Eiichi

    2016-06-01

    The aim of this study is to evaluate the effect of visual biofeedback therapy in acquiring supraglottic swallow (SGS) in a randomized-controlled trial with healthy individuals. Eighteen individuals (mean age, 26 years) who could not close or keep closed the vocal folds before and during the swallow in SGS were allocated randomly to either a visual biofeedback group (eight individuals) or a nonbiofeedback group (10 individuals). A videoendoscope was inserted intranasally and an SGS exercise, using 4 ml of green-colored water, was performed 30 times per day up to 5 days. When the participant failed to perform SGS, the result was provided only to the participants in the visual biofeedback group. The median length of time until acquiring SGS was 1.5 days in the visual biofeedback group and 3.5 days in the nonbiofeedback group (P=0.040). We concluded that visual biofeedback effectively enabled participants to acquire SGS earlier.

  20. Hybrid Visual Servoing Control for Robotic Arc Welding Based on Structured Light Vision

    Institute of Scientific and Technical Information of China (English)

    XUDe; WANGLin-Kun; TUZhi-Guo; TANMin

    2005-01-01

    A novel hybrid visual servoing control method based on structured light vision is proposed for robotic arc welding with a general six degrees of freedom robot. It consists of a position control inner-loop in Cartesian space and two outer-loops. One is position-based visual control inCartesian space for moving in the direction of weld seam, i.e., weld seam tracking, another is imagebased visual control in image space for adjustment to eliminate the errors in the process of tracking.A new Jacobian matrix from image space of the feature point on structured light stripe to Cartesian space is provided for differential movement of the end-effector. The control system model is simplified and its stability is discussed. An experiment of arc welding protected by gas CO2 for verifying is well conducted.

  1. Force control in the absence of visual and tactile feedback

    NARCIS (Netherlands)

    Mugge, W.; Abbink, D.A.; Schouten, Alfred Christiaan; van der Helm, F.C.T.; Arendzen, J.H.; Meskers, C.G.M.

    2013-01-01

    Motor control tasks like stance or object handling require sensory feedback from proprioception, vision and touch. The distinction between tactile and proprioceptive sensors is not frequently made in dynamic motor control tasks, and if so, mostly based on signal latency. We previously found that

  2. Surveillance of poisoning and drug overdose through hospital discharge coding, poison control center reporting, and the Drug Abuse Warning Network.

    Science.gov (United States)

    Blanc, P D; Jones, M R; Olson, K R

    1993-01-01

    There is no gold standard for determining poisoning incidence. We wished to compare four measures of poisoning incidence: International Classification of Diseases 9th Revision (ICD-9) principal (N-code) and supplemental external cause of injury (E-code) designations, poison control center (PCC) reporting, and detection by the Drug Abuse Warning Network (DAWN). We studied a case series at two urban hospitals. We assigned ICD-9 N-code and E-code classifications, determining whether these matched with medical records. We ascertained PCC and DAWN system reporting. A total of 724 subjects met entry criteria; 533 were studied (74%). We matched poisoning N-codes for 278 patients (52%), E-code by cause in 306 patients (57%), and E-code by intent in 171 patients (32%). A total of 383 patients (72%) received any poisoning N-code or any E-code. We found that PCC and DAWN reporting occurred for 123 of all patients (23%) and 399 of 487 eligible patients (82%), respectively. In multiple logistic regression, factors of age, hospital admission, suicidal intent, principal poisoning or overdose type, and mixed drug overdose were statistically significant predictors of case match or report varying by surveillance measure. Our findings indicate that common surveillance measures of poisoning and drug overdose may systematically undercount morbidity.

  3. Optimal performance of networked control systems with bandwidth and coding constraints.

    Science.gov (United States)

    Zhan, Xi-Sheng; Sun, Xin-xiang; Li, Tao; Wu, Jie; Jiang, Xiao-Wei

    2015-11-01

    The optimal tracking performance of multiple-input multiple-output (MIMO) discrete-time networked control systems with bandwidth and coding constraints is studied in this paper. The optimal tracking performance of networked control system is obtained by using spectral factorization technique and partial fraction. The obtained results demonstrate that the optimal performance is influenced by the directions and locations of the nonminimum phase zeros and unstable poles of the given plant. In addition to that, the characters of the reference signal, encoding, the bandwidth and additive white Gaussian noise (AWGN) of the communication channel are also closely influenced by the optimal tracking performance. Some typical examples are given to illustrate the theoretical results.

  4. Active magnetic bearing control loop modeling for a finite element rotordynamics code

    Science.gov (United States)

    Genta, Giancarlo; Delprete, Cristiana; Carabelli, Stefano

    1994-05-01

    A mathematical model of an active electromagnetic bearing which includes the actuator, the sensor and the control system is developed and implemented in a specialized finite element code for rotordynamic analysis. The element formulation and its incorporation in the model of the machine are described in detail. A solution procedure, based on a modal approach in which the number of retained modes is controlled by the user, is then shown together with other procedures for computing the steady-state response to both static and unbalance forces. An example of application shows the numerical results obtained on a model of an electric motor suspended on a five active-axis magnetic suspension. The comparison of some of these results with the experimental characteristics of the actual system shows the ability of the present model to predict its performance.

  5. Vcs.js - Visualization Control System for the Web

    Science.gov (United States)

    Chaudhary, A.; Lipsa, D.; Doutriaux, C.; Beezley, J. D.; Williams, D. N.; Fries, S.; Harris, M. B.

    2016-12-01

    VCS is a general purpose visualization library, optimized for climate data, which is part of the UV-CDAT system. It provides a Python API for drawing 2D plots such as lineplots, scatter plots, Taylor diagrams, data colored by scalar values, vector glyphs, isocontours and map projections. VCS is based on the VTK library. Vcs.js is the corresponding JavaScript API, designed to be as close as possible to the original VCS Python API and to provide similar functionality for the Web. Vcs.js includes additional functionality when compared with VCS. This additional API is used to introspect data files available on the server and variables available in a data file. Vcs.js can display plots in the browser window. It always works with a server that reads a data file, extracts variables from the file and subsets the data. From this point, two alternate paths are possible. First the system can render the data on the server using VCS producing an image which is send to the browser to be displayed. This path works for for all plot types and produces a reference image identical with the images produced by VCS. This path uses the VTK-Web library. As an optimization, usable in certain conditions, a second path is possible. Data is packed, and sent to the browser which uses a JavaScript plotting library, such as plotly, to display the data. Plots that work well in the browser are line-plots, scatter-plots for any data and many other plot types for small data and supported grid types. As web technology matures, more plots could be supported for rendering in the browser. Rendering can be done either on the client or on the server and we expect that the best place to render will change depending on the available web technology, data transfer costs, server management costs and value provided to users. We intend to provide a flexible solution that allows for both client and server side rendering and a meaningful way to choose between the two. We provide a web-based user interface called v

  6. Implementation of the Control Rod Movement Option by means of Control Variables in RELAP5/PARCS v2.7 Coupled Code (NUREG/IA-0402)

    OpenAIRE

    Miró Herrero, Rafael; Ana Ibáñez, Pablo; Barrachina Celda, Teresa María; Martínez-Murillo, J.C.; Pereira, C.; Verdú Martín, Gumersindo Jesús

    2014-01-01

    The objective of this work is to introduce an improvement in best estimate coupled neutronicthermalhydraulic 3D codes simulations, by adding a model for the control rod movement in the coupled code RELAP5/PARCS v2.7, by means of control variables, with the aim of being able to dynamically analyze asymmetric transient accidents, as the reactivity insertion accidents (RIA) in a nuclear reactor, reproducing all the reactors control systems. The modification developed in this work ...

  7. The Research on the Method of Visual Information Coding in Visual Cortex Prosthesis%视皮层假体中的视觉信息编码方法研究

    Institute of Scientific and Technical Information of China (English)

    邹冬兰

    2013-01-01

    The research on Visual Cortex Prosthesis has a very important meaning in ophthalmology.A Visual Cortex Prosthesis structure is designed, and also an image information coding based on visual mechanism is proposed.The simulation results of the actual image show that this method can not only guarantee the image quality, but also can make people use fewer neurons to represent the important information in natural images, so that it can provide a theoretical reference to the reducing of the number of the implant cortex stimulation electrodes.%视皮层假体的研究对眼科医学具有重要的意义;设计了一种视皮层假体的结构,提出了一种基于视觉机理的图像信息编码策略;实际图像的仿真结果表明,本方法在保证图像质量的前提下,能采用更少的神经元来表征自然图像中的重要信息,为减少植入皮层刺激电极的数量提供了理论参考.

  8. Stable visual PID control of a planar parallel robot

    Science.gov (United States)

    Garrido Moctezuma, Ruben; Soria López, Alberto; Trujano Cabrera, Miguel

    2008-11-01

    In this paper, we study an image-based PID control of a redundant planar parallel robot using a fixed camera configuration. The control objective is to move the robot end effector to the desired image reference position. The control law has a PD term plus an integral term with a nonlinear function of the position error. The proportional and integral actions use image loop information whereas the derivative action adds task space damping using joint level measurements. The Lyapunov method and the LaSalle invariance principle allow assessing asymptotic closed loop stability. Experiments show the feasibility of the proposed approach.

  9. A method of initial welding position guiding for arc welding robot based on visual servo control

    Institute of Scientific and Technical Information of China (English)

    郭振民; 陈善本; 邱涛; 吴林

    2003-01-01

    In order to solve the visual guiding task of initial welding position for arc welding robot, this paper presents a practice-prone image-based visual servo control strategy without calibration, and we perform validating experiments on a nine-DOF arc welding robot system. Experimental results illustrate presented method has the function to fulfill the task of welding robot initial positioning with certain anti-jamming ability. This method provides a basis for guiding welding gun to initial welding pose with real typical seam's image properties to replace flag block properties, and is a significant exploit to realize visual guiding of initial welding position and seam tracing in robot welding system.

  10. Design of novel non-contact multimedia controller for disability by using visual stimulus.

    Science.gov (United States)

    Pan, Jeng-Shyang; Lo, Chi-Chun; Tsai, Shang-Ho; Lin, Bor-Shyh

    2015-12-01

    The design of a novel non-contact multimedia controller is proposed in this study. Nowadays, multimedia controllers are generally used by patients and nursing assistants in the hospital. Conventional multimedia controllers usually involve in manual operation or other physical movements. However, it is more difficult for the disabled patients to operate the conventional multimedia controller by themselves; they might totally depend on others. Different from other multimedia controllers, the proposed system provides a novel concept of controlling multimedia via visual stimuli, without manual operation. The disabled patients can easily operate the proposed multimedia system by focusing on the control icons of a visual stimulus device, where a commercial tablet is used as the visual stimulus device. Moreover, a wearable and wireless electroencephalogram (EEG) acquisition device is also designed and implemented to easily monitor the user's EEG signals in daily life. Finally, the proposed system has been validated. The experimental result shows that the proposed system can effectively measure and extract the EEG feature related to visual stimuli, and its information transfer rate is also good. Therefore, the proposed non-contact multimedia controller exactly provides a good prototype of novel multimedia controlling scheme.

  11. Estudo do código visual originado do código verbal na linguagem jornalística Study of the visual code originated the verbal code in journalistic language

    Directory of Open Access Journals (Sweden)

    Leange Severo Alves

    1982-11-01

    Full Text Available Estudo da interação e importância da linguagem verbal e não verbal na comunicação na mensagem jornalística. Analisamos, dentro deste enfoque, a escrita como representação, a arte gráfica, o traçado e corpo do tipo. Analisamos também o modo e medida de composição e as cores no jornal como recursos visuais que chamam e prendem a atenção do leitor.Study on the interaction and importance of the verbal and non-verbal language in the journalistic message communication, Within this subject, we have analysed representative writing, graphic arts, design and letter-types body. We have also analysed composition format, colours and layout as visual appears which catch the reader's attention.

  12. Visual Recognition and Its Application to Robot Arm Control

    Directory of Open Access Journals (Sweden)

    Jih-Gau Juang

    2015-10-01

    Full Text Available This paper presents an application of optical word recognition and fuzzy control to a smartphone automatic test system. The system consists of a robot arm and two webcams. After the words from the control panel that represent commands are recognized by the robot system, the robot arm performs the corresponding actions to test the smartphone. One of the webcams is utilized to capture commands on the screen of the control panel, the other to recognize the words on the screen of the tested smartphone. The method of image processing is based on the Red-Green-Blue (RGB and Hue-Saturation-Luminance (HSL color spaces to reduce the influence of light. Fuzzy theory is used in the robot arm’s position control. The Optical Character Recognition (OCR technique is applied to the word recognition, and the recognition results are then checked by a dictionary process to increase the recognition accuracy. The camera which is used to recognize the tested smartphone also provides object coordinates to the fuzzy controller, then the robot arm moves to the desired positions and presses the desired buttons. The proposed control scheme allows the robot arm to perform different assigned test functions successfully.

  13. Control Framework for Dexterous Manipulation Using Dynamic Visual Servoing and Tactile Sensors’ Feedback

    Directory of Open Access Journals (Sweden)

    Carlos A. Jara

    2014-01-01

    Full Text Available Tactile sensors play an important role in robotics manipulation to perform dexterous and complex tasks. This paper presents a novel control framework to perform dexterous manipulation with multi-fingered robotic hands using feedback data from tactile and visual sensors. This control framework permits the definition of new visual controllers which allow the path tracking of the object motion taking into account both the dynamics model of the robot hand and the grasping force of the fingertips under a hybrid control scheme. In addition, the proposed general method employs optimal control to obtain the desired behaviour in the joint space of the fingers based on an indicated cost function which determines how the control effort is distributed over the joints of the robotic hand. Finally, authors show experimental verifications on a real robotic manipulation system for some of the controllers derived from the control framework.

  14. Visual Servo Control for the Hovering of an Outdoor Robotic Airship

    OpenAIRE

    AZINHEIRA, José R.; SILVEIRA, Geraldo; RIVES, Patrick; PAIVA, Ely C. de; CARVALHO, José R. H.; BUENO, Samuel Siqueira

    2010-01-01

    This paper addresses the issue of auto- matic hovering of an outdoor autonomous airship using image-based visual servoing. The hovering controller is designed using a full dynamic model of the airship, in a PD error feedback scheme, taking the visual signals as output and extracted from an on-board camera. The behavior and stability of the airship motion during the task execution and subjected to the wind disturbance is studied. The approach is nally validated in simulation using an ac...

  15. Combining Dense Structure From Motion and Visual SLAM in a Behavior-Based Robot Control Architecture

    OpenAIRE

    Geert De Cubber; Sid Ahmed Berrabah; Daniela Doroftei; Yvan Baudoin; Hichem Sahli

    2010-01-01

    In this paper, we present a control architecture for an intelligent outdoor mobile robot. This enables the robot to navigate in a complex, natural outdoor environment, relying on only a single on-board camera as sensory input. This is achieved through a twofold analysis of the visual data stream: a dense structure from motion algorithm calculates a depth map of the environment and a visual simultaneous localization and mapping algorithm builds a map of the surroundings using image features. T...

  16. Euler Technology Assessment - SPLITFLOW Code Applications for Stability and Control Analysis on an Advanced Fighter Model Employing Innovative Control Concepts

    Science.gov (United States)

    Jordan, Keith J.

    1998-01-01

    This report documents results from the NASA-Langley sponsored Euler Technology Assessment Study conducted by Lockheed-Martin Tactical Aircraft Systems (LMTAS). The purpose of the study was to evaluate the ability of the SPLITFLOW code using viscous and inviscid flow models to predict aerodynamic stability and control of an advanced fighter model. The inviscid flow model was found to perform well at incidence angles below approximately 15 deg, but not as well at higher angles of attack. The results using a turbulent, viscous flow model matched the trends of the wind tunnel data, but did not show significant improvement over the Euler solutions. Overall, the predictions were found to be useful for stability and control design purposes.

  17. Implementation of control rod movement and boron injection options by using control variables in RELAP5/PARCS V2.7 coupled code

    Energy Technology Data Exchange (ETDEWEB)

    Miro, R.; Barrachina, T.; Verdu, G. [Polytechnic University of Valencia (Spain). Chemical and Nuclear Engineering Department], e-mail: rmiro@iqn.upv.es, e-mail: tebarcel@upvnet.upv.es, e-mail: gverdu@iqn.upv.es; Pereira, C. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Mecanica], e-mail: claubia@nuclear.ufmg.br; Martinez-Murillo, J.C. [CNAT, Madrid (Spain)], e-mail: jcmm@cnat.es

    2009-07-01

    In actual neutron kinetics codes, control rods banks do not have the possibility of dynamic movement during the simulation of a transient; besides it is necessary to send the boron concentration from the thermal-hydraulic code to the neutronic code to account for changes in cross-sections due to boron dilution. For instance, control rod movements are pre-programmed with simple instructions introduced before the beginning of the calculation. Hence, control rod positions are not related to the core characteristics and the control systems at any time of the simulation. This work presents the changes introduced in RELAP5/PARCS v2.7 codes to achieve that control rods and the boron injection become more dynamic and realistic components in such kind of simulators (author)

  18. Use of a twin dataset to identify AMD-related visual patterns controlled by genetic factors

    Science.gov (United States)

    Quellec, Gwénolé; Abràmoff, Michael D.; Russell, Stephen R.

    2010-03-01

    The mapping of genotype to the phenotype of age-related macular degeneration (AMD) is expected to improve the diagnosis and treatment of the disease in a near future. In this study, we focused on the first step to discover this mapping: we identified visual patterns related to AMD which seem to be controlled by genetic factors, without explicitly relating them to the genes. For this purpose, we used a dataset of eye fundus photographs from 74 twin pairs, either monozygotic twins, who have the same genotype, or dizygotic twins, whose genes responsible for AMD are less likely to be identical. If we are able to differentiate monozygotic twins from dizygotic twins, based on a given visual pattern, then this pattern is likely to be controlled by genetic factors. The main visible consequence of AMD is the apparition of drusen between the retinal pigment epithelium and Bruch's membrane. We developed two automated drusen detectors based on the wavelet transform: a shape-based detector for hard drusen, and a texture- and color- based detector for soft drusen. Forty visual features were evaluated at the location of the automatically detected drusen. These features characterize the texture, the shape, the color, the spatial distribution, or the amount of drusen. A distance measure between twin pairs was defined for each visual feature; a smaller distance should be measured between monozygotic twins for visual features controlled by genetic factors. The predictions of several visual features (75.7% accuracy) are comparable or better than the predictions of human experts.

  19. Iterative development of visual control systems in a research vivarium.

    Directory of Open Access Journals (Sweden)

    James A Bassuk

    Full Text Available The goal of this study was to test the hypothesis that reintroduction of Continuous Performance Improvement (CPI methodology, a lean approach to management at Seattle Children's (Hospital, Research Institute, Foundation, would facilitate engagement of vivarium employees in the development and sustainment of a daily management system and a work-in-process board. Such engagement was implemented through reintroduction of aspects of the Toyota Production System. Iterations of a Work-In-Process Board were generated using Shewhart's Plan-Do-Check-Act process improvement cycle. Specific attention was given to the importance of detecting and preventing errors through assessment of the following 5 levels of quality: Level 1, customer inspects; Level 2, company inspects; Level 3, work unit inspects; Level 4, self-inspection; Level 5, mistake proofing. A functioning iteration of a Mouse Cage Work-In-Process Board was eventually established using electronic data entry, an improvement that increased the quality level from 1 to 3 while reducing wasteful steps, handoffs and queues. A visual workplace was realized via a daily management system that included a Work-In-Process Board, a problem solving board and two Heijunka boards. One Heijunka board tracked cage changing as a function of a biological kanban, which was validated via ammonia levels. A 17% reduction in cage changing frequency provided vivarium staff with additional time to support Institute researchers in their mutual goal of advancing cures for pediatric diseases. Cage washing metrics demonstrated an improvement in the flow continuum in which a traditional batch and queue push system was replaced with a supermarket-type pull system. Staff engagement during the improvement process was challenging and is discussed. The collective data indicate that the hypothesis was found to be true. The reintroduction of CPI into daily work in the vivarium is consistent with the 4P Model of the Toyota Way and

  20. Iterative development of visual control systems in a research vivarium.

    Science.gov (United States)

    Bassuk, James A; Washington, Ida M

    2014-01-01

    The goal of this study was to test the hypothesis that reintroduction of Continuous Performance Improvement (CPI) methodology, a lean approach to management at Seattle Children's (Hospital, Research Institute, Foundation), would facilitate engagement of vivarium employees in the development and sustainment of a daily management system and a work-in-process board. Such engagement was implemented through reintroduction of aspects of the Toyota Production System. Iterations of a Work-In-Process Board were generated using Shewhart's Plan-Do-Check-Act process improvement cycle. Specific attention was given to the importance of detecting and preventing errors through assessment of the following 5 levels of quality: Level 1, customer inspects; Level 2, company inspects; Level 3, work unit inspects; Level 4, self-inspection; Level 5, mistake proofing. A functioning iteration of a Mouse Cage Work-In-Process Board was eventually established using electronic data entry, an improvement that increased the quality level from 1 to 3 while reducing wasteful steps, handoffs and queues. A visual workplace was realized via a daily management system that included a Work-In-Process Board, a problem solving board and two Heijunka boards. One Heijunka board tracked cage changing as a function of a biological kanban, which was validated via ammonia levels. A 17% reduction in cage changing frequency provided vivarium staff with additional time to support Institute researchers in their mutual goal of advancing cures for pediatric diseases. Cage washing metrics demonstrated an improvement in the flow continuum in which a traditional batch and queue push system was replaced with a supermarket-type pull system. Staff engagement during the improvement process was challenging and is discussed. The collective data indicate that the hypothesis was found to be true. The reintroduction of CPI into daily work in the vivarium is consistent with the 4P Model of the Toyota Way and selected Principles

  1. Visual Servo Tracking Control of a Wheeled Mobile Robot with a Monocular Fixed Camera

    Science.gov (United States)

    2004-01-01

    41), it is clear that the controller developed in the previous section can not be applied to solve the regulation problem . In this section, an...extension is presented to illustrate how a visual servo controller can be developed to solve the regulation problem for the fixed camera configuration. To

  2. Ultrasonographic visualization of bleeding sites can help control postpartum hemorrhage using intrauterine balloon tamponade.

    Science.gov (United States)

    Kondoh, Eiji; Konishi, Mitsunaga; Kariya, Yoshitaka; Konishi, Ikuo

    2015-01-01

    Identification of precise bleeding sites is generally important to control hemorrhage. Nevertheless, the optimal technique to detect the bleeding sites has not yet been fully defined for patients with life-threatening post partum hemorrhage. We describe that ultrasonographic visualization of bleeding sites can help control post partum hemorrhage using intrauterine balloon tamponade. © 2014 Wiley Periodicals, Inc.

  3. Demonstration of visualization techniques for the control room engineer in 2030

    DEFF Research Database (Denmark)

    Marinelli, Mattia; Heussen, Kai; Strasser, Thomas

    2017-01-01

    Deliverable 8.1 reports results on analytics and visualizations of real time flexibility in support of voltage and frequency control in 2030+ power system. The investigation is carried out by means of relevant control room scenarios in order to derive the appropriate analytics needed for each...

  4. GOTHIC: Gravitational oct-tree code accelerated by hierarchical time step controlling

    CERN Document Server

    Miki, Yohei

    2016-01-01

    The tree method is a widely implemented algorithm for collisionless $N$-body simulations in astrophysics well suited for GPU(s). Adopting hierarchical time stepping can accelerate $N$-body simulations; however, it is infrequently implemented and its potential remains untested in GPU implementations. We have developed a Gravitational Oct-Tree code accelerated by HIerarchical time step Controlling named \\texttt{GOTHIC}, which adopts both the tree method and the hierarchical time step. The code adopts some adaptive optimizations by monitoring the execution time of each function on-the-fly and minimizes the time-to-solution by balancing the measured time of multiple functions. Results of performance measurements with realistic particle distribution performed on NVIDIA Tesla M2090, K20X, and GeForce GTX TITAN X, which are representative GPUs of the Fermi, Kepler, and Maxwell generation of GPUs, show that the hierarchical time step achieves a speedup by a factor of around 3--5 times compared to the shared time step...

  5. Three dimensional visualization to support command and control

    Energy Technology Data Exchange (ETDEWEB)

    Van Slambrook, G.A.

    1997-04-01

    Virtual reality concepts are changing the way one thinks about and with computers. The concepts have already proven their potential usefulness in a broad range of applications. This research was concerned with exploring and demonstrating the utility of virtual reality in robotics and satellite command and control applications. The robotics work addressed the need to quickly build accurate graphical models of physical environments by allowing a user to interactively build a model of a remote environment by superimposing stereo graphics onto live stereo video. The satellite work addressed the fusion of multiple data sets or models into one synergistic display for more effective training, design, and command and control of satellite systems.

  6. Soft-computing based visual control for unmanned vehicles

    OpenAIRE

    Olivares Méndez, Miguel Ángel

    2013-01-01

    El objetivo principal de esta Tesis es extender la utilización del “Soft- Computing” para el control de vehículos sin piloto utilizando visión. Este trabajo va más allá de los típicos sistemas de control utilizados en entornos altamente controlados, demonstrando la fuerza y versatilidad de la lógica difusa (Fuzzy Logic) para controlar vehículos aéreos y terrestres en un abanico de applicaciones diferentes. Para esta Tesis se ha realizado un gran número de pruebas reales en las cuales los cont...

  7. Evaluation of a visual biofeedback on the postural control in Parkinson's disease.

    Science.gov (United States)

    Caudron, S; Guerraz, M; Eusebio, A; Gros, J-P; Azulay, J-P; Vaugoyeau, M

    2014-01-01

    Both stabilization and orientation components of postural control are affected in Parkinson's disease (PD). These deficits are partly due to proprioceptive impairments, which frequently coexist with a visual dependence. This study aimed to evaluate if a visual biofeedback - i.e. real time anteroposterior trunk and head orientations indicated with a simplified avatar and represented in a head-mounted display - could improve the postural control of PD patients in response to a postural disturbance. The influence of focusing on one specific component of the postural control (stabilization or orientation) was also examined. Seventeen medicated PD patients performed sequences of pull-tests, either with eyes open, eyes closed or visual biofeedback, crossed with the verbal instruction to focus either on the stabilization or on the vertical body orientation. Kinematics data were collected. Backward trunk tilts consequent to the pulls were unchanged across the different conditions. With eyes open and eyes closed, patients did not recover their initial vertical orientation by adopting a slightly tilted backward position. This bias disappeared with the visual biofeedback. Moreover, falls consecutive to the test were significantly less frequent with the visual biofeedback than in the two other visual conditions. These different orientation and stabilization parameters were not affected by the instruction. Unlike a verbal instruction, visualizing in real time their own body's geometry improved both components of postural control of PD patients. This provides evidences in PD about links between impaired vertical orientation, deficits in balance control, and contribution of supplementary sensory cues. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  8. Laser-induced thermotherapy of benign and malignant tumors controlled by color-coded duplex sonography

    Science.gov (United States)

    Philipp, Carsten M.; Rohde, Ewa; Waldschmidt, Juergen; Berlien, Hans-Peter

    1994-12-01

    Since 1984 we use the interstitial application of laser induced thermotherapy (LITT) for the treatment of congenital vascular disorders (CVD) such as hemangiomas and vascular malformations. In most of the procedures a 600 micron core bare fiber is used to deliver the radiation of a cw Nd:YAG laser emitting at 1064 nm into the diseased tissue. As most of the CVD treated this way are located subcutaneously, the localization of the fiber and the interstitial laser coagulation (ILC) is controlled by transillumination and palpitation of the heat expansion of the skin surface, this way a crepitation can also be detected during the ILC. As the ILC in deeper body structures cannot be controlled directly we use color coded duplex sonography (CCDS), both for diagnostic and treatment control. In the procedures where we use the B-scan image for puncture control, a color signal is displayed representing tissue movements. These movements caused by degasification and vapor are those detectable as crepitations when using direct control. The color signal starts, changes, and moves in a reproducible pattern following the heat distribution and the subsequently occurring degasification in the tissue. Also the changes in perfusion are detectable by the means of CCDS. The precise extent of the coagulation is visible in the B-scan several minutes after laser exposure. The clinical experience and an extensive experimental evaluation has proven that CCDS is a valuable real time method to monitor the tissue reaction in ILC-procedures. For two years we have performed ILC-procedures with CCDS control in patients with CVD (n equals 65) successfully. Because of its reliable imaging and the clinical advantages recently we applied this type of ILC-control to the palliative treatment of nonresectable primary and secondary liver tumors (n equals 3) and subcutaneous metastases of mamma carcinoma. (n equals 6).

  9. Application of hybrid coded genetic algorithm in fuzzy neural network controller

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Presents the fuzzy neural network optimized by hybrid coded genetic algorithm of decimal encoding and bi nary encoding, the searching ability and stability of genetic algorithms enhanced by using binary encoding during the crossover operation and decimal encoding during the mutation operation, and the way of accepting new individuals by probability adopted, by which a new individual is accepted and its parent is discarded when its fitness is higher than that of its parent, and a new individual is accepted by probability when its fitness is lower than that of its parent. And concludes with calculations made with an example that these improvements enhance the speed of genetic algorithms to optimize the fuzzy neural network controller.

  10. Scalable video object coding & QoS control for next generation space internet

    Institute of Scientific and Technical Information of China (English)

    TU GuoFang; ZHANG Can; HEINRICH Nimann; XU Jie; WU WeiRen

    2008-01-01

    The next generation space internet (NGSI) is based on all-IP-based mobile network that merges land-based network, sea-based network, sky-based network, space-based network, deep space-based network together using existing assess network technologies. There are high signal propagation delays, high error rate, bandwidth variation and time-variety in NGSI. In order to adapt to various space communica-tion environment constraints and bandwidth variation, we propose a reduced di-mension scalable video coding scheme based on CCSDS IDCS algorithm and quality of service (QoS) control method by cross layer design (CLD). The experi-mental result shows that this new method has better performance than that of ex-isting algorithms, and can be adaptive to the bandwidth variation dynamically.

  11. Postural control responses sitting on unstable board during visual stimulation

    Science.gov (United States)

    Mizuno, Y.; Shindo, M.; Kuno, S.; Kawakita, T.; Watanabe, S.

    2001-08-01

    Concerning with the relation of vection induced by the optokinetic stimulation and the body movement, especially we attended to the neck joint movement, which counteracted to the shoulder movement. Then, we analyzed the mechanisms of the sitting postural control by using the seesaw board. By the optokinetic stimulation through the head mounted display (H.M.D.), the vection was leaded, and it affected to the sway of the body on the seesaw board. In this experiment, we found that the movement of upper part of body except for the head was the same direction to the seesaw board but the head moved out of phase to the seesaw board. This phenomenon will be suggested that the unstable condition of sway is balanced by the counter swing of head and the neck muscle tonus is controlled by acting of the vestiburo-collic reflex.

  12. A systematic review of controlled trials on visual stress using Intuitive Overlays or the Intuitive Colorimeter.

    Science.gov (United States)

    Evans, Bruce J W; Allen, Peter M

    2016-01-01

    Claims that coloured filters aid reading date back 200 years and remain controversial. Some claims, for example, that more than 10% of the general population and 50% of people with dyslexia would benefit from coloured filters lack sound evidence and face validity. Publications with such claims typically cite research using methods that have not been described in the scientific literature and lack a sound aetiological framework. Notwithstanding these criticisms, some researchers have used more rigorous selection criteria and methods of prescribing coloured filters that were developed at a UK Medical Research Council unit and which have been fully described in the scientific literature. We review this research and disconfirm many of the more extreme claims surrounding this topic. This literature indicates that a minority subset of dyslexics (circa 20%) may have a condition described as visual stress which most likely results from a hyperexcitability of the visual cortex. Visual stress is characterised by symptoms of visual perceptual distortions, headaches, and eyestrain when viewing repetitive patterns, including lines of text. This review indicates that visual stress is distinct from, although sometimes co-occurs with, dyslexia. Individually prescribed coloured filters have been shown to improve reading performance in people with visual stress, but are unlikely to influence the phonological and memory deficits associated with dyslexia and therefore are not a treatment for dyslexia. This review concludes that larger and rigorous randomised controlled trials of interventions for visual stress are required. Improvements in the diagnosis of the condition are also a priority.

  13. Visually Guiding and Controlling the Search While Mining Chemical Structures

    OpenAIRE

    Max Pereira; Vitor Santos Costa; Rui Camacho; Fonseca, Nuno A.

    2009-01-01

    In this paper we present the work in progress on LogCHEM, an ILP based tool for discriminative interactive mining of chemical fragments. In particular, we describe the integration with a molecule visualisation software that allows the chemist to graphically control the search for interesting patterns in chemical fragments. Furthermore, we show how structured information, such as rings, functional groups like carboxyl, amine, methyl, ester, etc are integrated and exploited in LogCHEM.

  14. Visual servo control for a human-following robot

    CSIR Research Space (South Africa)

    Burke, Michael G

    2011-03-01

    Full Text Available control applications because of their ease of implementation. Unfortunately, colour matching leads to difficulties in extracting reliably positioned feature points and is subject to mismatches. The use of fiduciary markers alleviates potential... mismatches, but requires interference with the target, which is not always possible. One of the most common fiduciary approaches, template matching, involves the design of an easily recognised marker and complementary filter, which is then correlated...

  15. The interaction between emotion and executive control: Comparison between visual, auditory, and tactile modalities.

    Science.gov (United States)

    Fruchtman-Steinbok, Tom; Salzer, Yael; Henik, Avishai; Cohen, Noga

    2017-08-01

    The reciprocal connections between emotion and attention are vital for adaptive behaviour. Previous results demonstrated that the behavioural effects of emotional stimuli on performance are attenuated when executive control is recruited. The current research studied whether this attenuation is modality dependent. In two experiments, negative and neutral pictures were presented shortly before a visual, tactile, or auditory target in a Simon task. All three modalities demonstrated a Simon effect, a conflict adaptation effect, and an emotional interference effect. However, the interaction between picture valence and Simon congruency was found only in the visual task. Specifically, when the Simon target was visual, emotional interference was reduced during incongruent compared to congruent trials. These findings suggest that although the control-related effects observed in the Simon tasks are not modality dependent, the link between emotion and executive control is modality dependent. Presumably, this link occurs only when the emotional stimulus and the target are presented in the same modality.

  16. Development of visual motion perception for prospective control: Brain and behavioural studies in infants

    Directory of Open Access Journals (Sweden)

    Seth B. Agyei

    2016-02-01

    Full Text Available During infancy, smart perceptual mechanisms develop allowing infants to judge time-space motion dynamics more efficiently with age and locomotor experience. This emerging capacity may be vital to enable preparedness for upcoming events and to be able to navigate in a changing environment. Little is known about brain changes that support the development of prospective control and about processes, such as preterm birth, that may compromise it. As a function of perception of visual motion, this paper will describe behavioural and brain studies with young infants investigating the development of visual perception for prospective control. By means of the three visual motion paradigms of occlusion, looming, and optic flow, our research shows the importance of including behavioural data when studying the neural correlates of prospective control.

  17. ASPNET AJAX Control Development with Visual Studio 2008 and NET 35 Framework

    CERN Document Server

    White, Damien

    2010-01-01

    This Wrox Blox empowers developers to develop ASP.NET AJAX controls by giving them a look "under the hood" of AJAX controls. While this Wrox Blox focuses on Visual Studio 2008 and .NET 3.5, developers should know that the concepts for creating custom controls in Visual Studio 2005 and .NET 2.0 with ASP.NET AJAX 1.0 are very similar. Visual Studio 2008 offers many improvements concerning JavaScript editing/debugging, and .NET 3.5 includes ASP.NET AJAX right out of the box, simplifying the install to get AJAX up and running. This Wrox Blox takes developers gradually through creating a custom ASP

  18. Visual Servoing of a Conventional CNC Machine Using an External Axis Controller

    Directory of Open Access Journals (Sweden)

    Daniel Hanafi

    2003-04-01

    Full Text Available This paper presents the implementation of an external axis control system on a conventional CNC machine so that the machine can be actively controlled in response to sensors such as vision and force. The controller that runs on an external computer has direct access to the CNC controller for machine position sensing. The control signals to the machine are sent through purpose built circuitry via the machine's manual pulse generator (MPG inputs. To demonstrate the accuracy and performance of the control system, it was used to visually track the profile of a mandrel used for shear spinning. The implemented system eliminates the parallax error and the need to use an accurate pixel resolution. The raw tracking data is processed by a curvature detection algorithm that detects linear and circular segments and segment transitions. The results show that the visual tracking system provides accurate tracking results that are well within the tolerances used in the industry.

  19. Completion time reduction in instantly decodable network coding through decoding delay control

    KAUST Repository

    Douik, Ahmed S.

    2014-12-01

    For several years, the completion time and the decoding delay problems in Instantly Decodable Network Coding (IDNC) were considered separately and were thought to completely act against each other. Recently, some works aimed to balance the effects of these two important IDNC metrics but none of them studied a further optimization of one by controlling the other. In this paper, we study the effect of controlling the decoding delay to reduce the completion time below its currently best known solution. We first derive the decoding-delay-dependent expressions of the users\\' and their overall completion times. Although using such expressions to find the optimal overall completion time is NP-hard, we use a heuristic that minimizes the probability of increasing the maximum of these decoding-delay-dependent completion time expressions after each transmission through a layered control of their decoding delays. Simulation results show that this new algorithm achieves both a lower mean completion time and mean decoding delay compared to the best known heuristic for completion time reduction. The gap in performance becomes significant for harsh erasure scenarios.

  20. A Fuzzy Logic Based Power Control for Wideband Code Division Multiple Access Wireless Networks

    Directory of Open Access Journals (Sweden)

    T. Ravichandran

    2012-01-01

    Full Text Available Problem statement: Resource management is one of the most important engineering issues in 3G systems where multiple traffic classes are supported each being characterized by its required Quality of Service (QoS parameters. Call Admission Control (CAC is one of the resource management functions, which regulates network access to ensure QoS provisioning. Efficient CAC is necessary for the QoS provisioning in WCDMA environment. The effective functioning of WCDMA systems is influenced by the power control utility. Approach: In this study, we propose to design a fuzzy logic based power control for Wideband Code Division Multiple Access Wireless Networks. This proposed technique is aimed at multiple services like voice, video and data for multiclass users. The fuzzy logic technique is used to estimate the optimal admissible users group inclusive of optimum transmitting power level. This technique reduces the interference level and call rejection rate. Results: By simulation results, we demonstrate that the proposed technique achieve reduced energy consumption for a cell with increased throughput. Conclusion: The proposed technique minimizes the power consumption and call rejection rate.

  1. Proof-of-Concept Demonstration Results for Robotic Visual Servo Controllers

    Energy Technology Data Exchange (ETDEWEB)

    Chawda, P.V.

    2004-09-22

    There is significant motivation to provide robotic systems with improved autonomy as a means to significantly accelerate deactivation and decommissioning operations while also reducing the associated costs, removing human operators from hazardous environments, and reducing the required burden and skill of human operators. To achieve improved autonomy, fundamental research is focused on the challenges of developing visual servo controllers. The challenge in developing these controllers is that a camera provides 2-dimensional image information about the 3-dimensional Euclidean-space through a perspective (range dependent) projection that can be corrupted by uncertainty in the camera calibration matrix. Disturbances in this relationship (i.e., corruption in the sensor information) propagate erroneous information to the feedback controller of the robot, leading to potentially unpredictable task execution. This technical manual describes 3 proof-of-concept demonstrations of visual servo controllers developed from fundamental research aimed at these challenges. Specifically, one section describes the implementation of a cooperative visual servo control scheme with a camera-in-hand and a fixed camera to track a moving target despite uncertainty in the camera calibration and the unknown constant distance from the camera to a target where the camera is mounted on the end-effector of a 6 degrees-of-freedom hydraulic robot manipulator. The next section describes the implementation of 2 homography-based visual servo tracking and regulation controllers for a mobile robot with a calibrated camera despite an unknown time-varying distance from the camera to a target.

  2. Top-Down Control of Visual Alpha Oscillations: Sources of Control Signals and Their Mechanisms of Action.

    Science.gov (United States)

    Wang, Chao; Rajagovindan, Rajasimhan; Han, Sahng-Min; Ding, Mingzhou

    2016-01-01

    Alpha oscillations (8-12 Hz) are thought to inversely correlate with cortical excitability. Goal-oriented modulation of alpha has been studied extensively. In visual spatial attention, alpha over the region of visual cortex corresponding to the attended location decreases, signifying increased excitability to facilitate the processing of impending stimuli. In contrast, in retention of verbal working memory, alpha over visual cortex increases, signifying decreased excitability to gate out stimulus input to protect the information held online from sensory interference. According to the prevailing model, this goal-oriented biasing of sensory cortex is effected by top-down control signals from frontal and parietal cortices. The present study tests and substantiates this hypothesis by (a) identifying the signals that mediate the top-down biasing influence, (b) examining whether the cortical areas issuing these signals are task-specific or task-independent, and (c) establishing the possible mechanism of the biasing action. High-density human EEG data were recorded in two experimental paradigms: a trial-by-trial cued visual spatial attention task and a modified Sternberg working memory task. Applying Granger causality to both sensor-level and source-level data we report the following findings. In covert visual spatial attention, the regions exerting top-down control over visual activity are lateralized to the right hemisphere, with the dipoles located at the right frontal eye field (FEF) and the right inferior frontal gyrus (IFG) being the main sources of top-down influences. During retention of verbal working memory, the regions exerting top-down control over visual activity are lateralized to the left hemisphere, with the dipoles located at the left middle frontal gyrus (MFG) being the main source of top-down influences. In both experiments, top-down influences are mediated by alpha oscillations, and the biasing effect is likely achieved via an inhibition

  3. 3D Scan-Based Wavelet Transform and Quality Control for Video Coding

    Directory of Open Access Journals (Sweden)

    Parisot Christophe

    2003-01-01

    Full Text Available Wavelet coding has been shown to achieve better compression than DCT coding and moreover allows scalability. 2D DWT can be easily extended to 3D and thus applied to video coding. However, 3D subband coding of video suffers from two drawbacks. The first is the amount of memory required for coding large 3D blocks; the second is the lack of temporal quality due to the sequence temporal splitting. In fact, 3D block-based video coders produce jerks. They appear at blocks temporal borders during video playback. In this paper, we propose a new temporal scan-based wavelet transform method for video coding combining the advantages of wavelet coding (performance, scalability with acceptable reduced memory requirements, no additional CPU complexity, and avoiding jerks. We also propose an efficient quality allocation procedure to ensure a constant quality over time.

  4. The Next Generation of Ground Operations Command and Control; Scripting in C Sharp and Visual Basic

    Science.gov (United States)

    Ritter, George; Pedoto, Ramon

    2010-01-01

    This slide presentation reviews the use of scripting languages in Ground Operations Command and Control. It describes the use of scripting languages in a historical context, the advantages and disadvantages of scripts. It describes the Enhanced and Redesigned Scripting (ERS) language, that was designed to combine the features of a scripting language and the graphical and IDE richness of a programming language with the utility of scripting languages. ERS uses the Microsoft Visual Studio programming environment and offers custom controls that enable an ERS developer to extend the Visual Basic and C sharp language interface with the Payload Operations Integration Center (POIC) telemetry and command system.

  5. Simulator of the punctual kinetics of a TRIGA Mark III reactor with power diffuse control in a visual environment; Simulador de la cinetica puntual de un reactor nuclear TRIGA Mark III con control difuso de potencia en un ambiente visual

    Energy Technology Data Exchange (ETDEWEB)

    Perez M, C

    2004-07-01

    The development of a software is presented that simulates the punctual kinetics of a nuclear reactor of investigation model TRIGA Mark III, generating the answers of the reactor low different algorithms of control of power. The user requires a graphic interface that allows him easily interacting with the simulator. To achieve the proposed objective, first the system was modeled in open loop, not using a mathematical model of the consistent reactor in a system of linear ordinary differential equations. For their solution in real time the numeric method of Runge-Kutta-Fehlberg was used. As second phase, it was modeled to the system in closed loop, using for it an algorithm of control of the power based on fuzzy logic. This software has as purpose to help the investigator in the control area who will be able to prove different algorithms for the control of the power of the reactor. This is achieved using the code source in language C, C++, Visual Basic, with which a file is generated. DLL and it is inserted in the simulator. Then they will be able to visualize the results as if their controller had installed in the reactor, analyzing the behavior of all his variables that will be stored in files, for his later study. The easiness of proving these control algorithms in the reactor without necessity to make it physically has important consequences as the saving in the expense of fuel, the not generation of radioactive waste and the most important thing, one doesn't run any risk. The simulator can be used how many times it is necessary until the total purification of the algorithm. This program is the base for following investigation processes, enlarging the capacities and options of the same one. The program fulfills the time of execution satisfactorily, assisting to the necessity of visualizing the behavior in real time of the reactor, and it responds from an effective way to the petitions of changes of power on the part of the user. (Author)

  6. Real-Time Inverse Optimal Neural Control for Image Based Visual Servoing with Nonholonomic Mobile Robots

    Directory of Open Access Journals (Sweden)

    Carlos López-Franco

    2015-01-01

    Full Text Available We present an inverse optimal neural controller for a nonholonomic mobile robot with parameter uncertainties and unknown external disturbances. The neural controller is based on a discrete-time recurrent high order neural network (RHONN trained with an extended Kalman filter. The reference velocities for the neural controller are obtained with a visual sensor. The effectiveness of the proposed approach is tested by simulations and real-time experiments.

  7. Robotic Label Applicator: Design, Development and Visual Servoing Based Control

    Directory of Open Access Journals (Sweden)

    Lin Chyi-Yeu

    2016-01-01

    Full Text Available Use of robotic arms and computer vision in manufacture, and assembly process are getting more interest as flexible customization is becoming priority over mass production as frontier industry practice. In this paper an innovative label applicator as end of arm tooling (EOAT capable of dispensing and applying label stickers of various dimensions to a product is designed, fabricated and tested. The system incorporates a label dispenserapplicator and had eye-in-hand camera system, attached to 6-dof robot arm can autonomously apply a label sticker to the target position on a randomly placed product. Employing multiple advantages from different knowledge basis, mechanism design and vision based automatic control, offers this system distinctive efficiency as well as flexibility to change in manufacturing and assembly process with time and cost saving.

  8. Cracking the code of oscillatory activity.

    Directory of Open Access Journals (Sweden)

    Philippe G Schyns

    2011-05-01

    Full Text Available Neural oscillations are ubiquitous measurements of cognitive processes and dynamic routing and gating of information. The fundamental and so far unresolved problem for neuroscience remains to understand how oscillatory activity in the brain codes information for human cognition. In a biologically relevant cognitive task, we instructed six human observers to categorize facial expressions of emotion while we measured the observers' EEG. We combined state-of-the-art stimulus control with statistical information theory analysis to quantify how the three parameters of oscillations (i.e., power, phase, and frequency code the visual information relevant for behavior in a cognitive task. We make three points: First, we demonstrate that phase codes considerably more information (2.4 times relating to the cognitive task than power. Second, we show that the conjunction of power and phase coding reflects detailed visual features relevant for behavioral response--that is, features of facial expressions predicted by behavior. Third, we demonstrate, in analogy to communication technology, that oscillatory frequencies in the brain multiplex the coding of visual features, increasing coding capacity. Together, our findings about the fundamental coding properties of neural oscillations will redirect the research agenda in neuroscience by establishing the differential role of frequency, phase, and amplitude in coding behaviorally relevant information in the brain.

  9. Relationship between reaction time, fine motor control, and visual-spatial perception on vigilance and visual-motor tasks in 22q11.2 Deletion Syndrome.

    LENUS (Irish Health Repository)

    Howley, Sarah A

    2012-10-15

    22q11.2 Deletion Syndrome (22q11DS) is a common microdeletion disorder associated with mild to moderate intellectual disability and specific neurocognitive deficits, particularly in visual-motor and attentional abilities. Currently there is evidence that the visual-motor profile of 22q11DS is not entirely mediated by intellectual disability and that these individuals have specific deficits in visual-motor integration. However, the extent to which attentional deficits, such as vigilance, influence impairments on visual motor tasks in 22q11DS is unclear. This study examines visual-motor abilities and reaction time using a range of standardised tests in 35 children with 22q11DS, 26 age-matched typically developing (TD) sibling controls and 17 low-IQ community controls. Statistically significant deficits were observed in the 22q11DS group compared to both low-IQ and TD control groups on a timed fine motor control and accuracy task. The 22q11DS group performed significantly better than the low-IQ control group on an untimed drawing task and were equivalent to the TD control group on point accuracy and simple reaction time tests. Results suggest that visual motor deficits in 22q11DS are primarily attributable to deficits in psychomotor speed which becomes apparent when tasks are timed versus untimed. Moreover, the integration of visual and motor information may be intact and, indeed, represent a relative strength in 22q11DS when there are no time constraints imposed. While this may have significant implications for cognitive remediation strategies for children with 22q11DS, the relationship between reaction time, visual reasoning, cognitive complexity, fine motor speed and accuracy, and graphomotor ability on visual-motor tasks is still unclear.

  10. Visual Servoing

    OpenAIRE

    Chaumette, Francois; Hutchinson, Seth; Corke, Peter

    2016-01-01

    International audience; This chapter introduces visual servo control, using computer vision data in the servo loop to control the motion of a robot. We first describe the basic techniques that are by now well established in the field. We give a general overview of the formulation of the visual servo control problem, and describe the two archetypal visual servo control schemes: image-based and pose-based visual servo control. We then discuss performance and stability issues that pertain to the...

  11. Working memory load and distraction: dissociable effects of visual maintenance and cognitive control.

    Science.gov (United States)

    Konstantinou, Nikos; Beal, Eleanor; King, Jean-Remi; Lavie, Nilli

    2014-10-01

    We establish a new dissociation between the roles of working memory (WM) cognitive control and visual maintenance in selective attention as measured by the efficiency of distractor rejection. The extent to which focused selective attention can prevent distraction has been shown to critically depend on the level and type of load involved in the task. High perceptual load that consumes perceptual capacity leads to reduced distractor processing, whereas high WM load that reduces WM ability to exert priority-based executive cognitive control over the task results in increased distractor processing (e.g., Lavie, Trends in Cognitive Sciences, 9(2), 75-82, 2005). WM also serves to maintain task-relevant visual representations, and such visual maintenance is known to recruit the same sensory cortices as those involved in perception (e.g., Pasternak & Greenlee, Nature Reviews Neuroscience, 6(2), 97-107, 2005). These findings led us to hypothesize that loading WM with visual maintenance would reduce visual capacity involved in perception, thus resulting in reduced distractor processing-similar to perceptual load and opposite to WM cognitive control load. Distractor processing was assessed in a response competition task, presented during the memory interval (or during encoding; Experiment 1a) of a WM task. Loading visual maintenance or encoding by increased set size for a memory sample of shapes, colors, and locations led to reduced distractor response competition effects. In contrast, loading WM cognitive control with verbal rehearsal of a random letter set led to increased distractor effects. These findings confirm load theory predictions and provide a novel functional distinction between the roles of WM maintenance and cognitive control in selective attention.

  12. MARE2DEM: a 2-D inversion code for controlled-source electromagnetic and magnetotelluric data

    Science.gov (United States)

    Key, Kerry

    2016-10-01

    This work presents MARE2DEM, a freely available code for 2-D anisotropic inversion of magnetotelluric (MT) data and frequency-domain controlled-source electromagnetic (CSEM) data from onshore and offshore surveys. MARE2DEM parametrizes the inverse model using a grid of arbitrarily shaped polygons, where unstructured triangular or quadrilateral grids are typically used due to their ease of construction. Unstructured grids provide significantly more geometric flexibility and parameter efficiency than the structured rectangular grids commonly used by most other inversion codes. Transmitter and receiver components located on topographic slopes can be tilted parallel to the boundary so that the simulated electromagnetic fields accurately reproduce the real survey geometry. The forward solution is implemented with a goal-oriented adaptive finite-element method that automatically generates and refines unstructured triangular element grids that conform to the inversion parameter grid, ensuring accurate responses as the model conductivity changes. This dual-grid approach is significantly more efficient than the conventional use of a single grid for both the forward and inverse meshes since the more detailed finite-element meshes required for accurate responses do not increase the memory requirements of the inverse problem. Forward solutions are computed in parallel with a highly efficient scaling by partitioning the data into smaller independent modeling tasks consisting of subsets of the input frequencies, transmitters and receivers. Non-linear inversion is carried out with a new Occam inversion approach that requires fewer forward calls. Dense matrix operations are optimized for memory and parallel scalability using the ScaLAPACK parallel library. Free parameters can be bounded using a new non-linear transformation that leaves the transformed parameters nearly the same as the original parameters within the bounds, thereby reducing non-linear smoothing effects. Data

  13. 40 CFR Appendix K to Subpart A of... - Commodity Codes From the Harmonized Tariff Schedule for Controlled Substances and Used Controlled...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Commodity Codes From the Harmonized Tariff Schedule for Controlled Substances and Used Controlled Substances K Appendix K to Subpart A of...) PROTECTION OF STRATOSPHERIC OZONE Production and Consumption Controls Pt. 82, Subpt. A, App. K Appendix K to...

  14. Visual Spatial Attention Training Improve Spatial Attention and Motor Control for Unilateral Neglect Patients.

    Science.gov (United States)

    Wang, Wei; Ji, Xiangtong; Ni, Jun; Ye, Qian; Zhang, Sicong; Chen, Wenli; Bian, Rong; Yu, Cui; Zhang, Wenting; Shen, Guangyu; Machado, Sergio; Yuan, Tifei; Shan, Chunlei

    2015-01-01

    To compare the effect of visual spatial training on the spatial attention to that on motor control and to correlate the improvement of spatial attention to motor control progress after visual spatial training in subjects with unilateral spatial neglect (USN). 9 cases with USN after right cerebral stroke were randomly divided into Conventional treatment group + visual spatial attention and Conventional treatment group. The Conventional treatment group + visual spatial attention received conventional rehabilitation therapy (physical and occupational therapy) and visual spatial attention training (optokinetic stimulation and right half-field eye patching). The Conventional treatment group was only treated with conventional rehabilitation training (physical and occupational therapy). All patients were assessed by behavioral inattention test (BIT), Fugl-Meyer Assessment of motor function (FMA), equilibrium coordination test (ECT) and non-equilibrium coordination test (NCT) before and after 4 weeks treatment. Total scores in both groups (without visual spatial attention/with visual spatial attention) improved significantly (BIT: P=0.021/P=0.000, d=1.667/d=2.116, power=0.69/power=0.98, 95%CI[-0.8839,45.88]/95%CI=[16.96,92.64]; FMA: P=0.002/P=0.000, d=2.521/d=2.700, power=0.93/power=0.98, 95%CI[5.707,30.79]/95%CI=[16.06,53.94]; ECT: P=0.002/ P=0.000, d=2.031/d=1.354, power=0.90/power=0.17, 95%CI[3.380,42.61]/95%CI=[-1.478,39.08]; NCT: P=0.013/P=0.000, d=1.124/d=1.822, power=0.41/power=0.56, 95%CI[-7.980,37.48]/95%CI=[4.798,43.60],) after treatment. Among the 2 groups, the group with visual spatial attention significantly improved in BIT (P=0.003, d=3.103, power=1, 95%CI[15.68,48.92]), FMA of upper extremity (P=0.006, d=2.771, power=1, 95%CI[5.061,20.14]) and NCT (P=0.010, d=2.214, power=0.81-0.90, 95%CI[3.018,15.88]). Correlative analysis shows that the change of BIT scores is positively correlated to the change of FMA total score (r=0.77, Pmotor control functions in

  15. Control of the flow behind a backward-facing step by visual feedback

    CERN Document Server

    Gautier, N

    2013-01-01

    The separated flow downstream a backward-facing step is controlled using visual information for feedback. This is done when looking at the flow from two vantage points. Flow velocity fields are computed in real-time and used to yield inputs to a control loop. This approach to flow control is shown to be able to control the detached flow in the same way as has been done before by using the area of the recirculation region downstream the step as input for a gradient descent optimization scheme. Visual feedback using real-time computations of 2D velocity fields also allows for novel inputs to the feedback scheme. As a proof of concept, the spatially averaged value of the swirling strength is successfully used as input for an automatically tuned PID controller.

  16. Image-Based Visual Servoing for Manipulation Via Predictive Control – A Survey of Some Results

    Directory of Open Access Journals (Sweden)

    Corneliu Lazăr

    2016-09-01

    Full Text Available In this paper, a review of predictive control algorithms developed by the authors for visual servoing of robots in manipulation applications is presented. Using these algorithms, a control predictive framework was created for image-based visual servoing (IBVS systems. Firstly, considering the point features, in the year 2008 we introduced an internal model predictor based on the interaction matrix. Secondly, distinctly from the set-point trajectory, we introduced in 2011 the reference trajectory using the concept from predictive control. Finally, minimizing a sum of squares of predicted errors, the optimal input trajectory was obtained. The new concept of predictive control for IBVS systems was employed to develop a cascade structure for motion control of robot arms. Simulation results obtained with a simulator for predictive IBVS systems are also presented.

  17. Visualization of calcium transients controlling orientation of ciliary beat.

    Science.gov (United States)

    Tamm, S L; Terasaki, M

    1994-06-01

    To image changes in intraciliary Ca controlling ciliary motility, we microinjected Ca Green dextran, a visible wavelength fluorescent Ca indicator, into eggs or two cell stages of the ctenophore Mnemiopsis leidyi. The embryos developed normally into free-swimming, approximately 0.5 mm cydippid larvae with cells and ciliary comb plates (approximately 100 microns long) loaded with the dye. Comb plates of larvae, like those of adult ctenophores, undergo spontaneous or electrically stimulated reversal of beat direction, triggered by Ca influx through voltage-sensitive Ca channels. Comb plates of larvae loaded with Ca Green dextran emit spontaneous or electrically stimulated fluorescent flashes along the entire length of their cilia, correlated with ciliary reversal. Fluorescence intensity peaks rapidly (34-50 ms), then slowly falls to resting level in approximately 1 s. Electrically stimulated Ca Green emissions often increase in steps to a maximum value near the end of the stimulus pulse train, and slowly decline in 1-2 s. In both spontaneous and electrically stimulated flashes, measurements at multiple sites along a single comb plate show that Ca Green fluorescence rises within 17 ms (1 video field) and to a similar relative extent above resting level from base to tip of the cilia. The decline of fluorescence intensity also begins simultaneously and proceeds at similar rates along the ciliary length. Ca-free sea water reversibly abolishes spontaneous and electrically stimulated Ca Green ciliary emissions as well as reversed beating. Calculations of Ca diffusion from the ciliary base show that Ca must enter the comb plate along the entire length of the ciliary membranes. The voltage-dependent Ca channels mediating changes in beat direction are therefore distributed over the length of the comb plate cilia. The observed rapid and virtually instantaneous Ca signal throughout the intraciliary space may be necessary for reprogramming the pattern of dynein activity

  18. Rating Correlations Between Customs Codes and Export Control Lists: Assessing the Needs and Challenges

    Energy Technology Data Exchange (ETDEWEB)

    Chatelus, Renaud; Heine, Pete

    2016-01-01

    Correlation tables are the linchpins between the customs codes used to classify commodities in international trade and the control lists used for strategic trade control (STC) purposes. While understanding the customs classification system can help the STC community better understand strategic trade flows, better identify which trade operations require permits, and more effectively detect illegal exports, the two systems are different in scope, philosophy, content, and objectives. Many indications point to the limitations of these correlation tables, and it is important to understand the nature of the limitations and the complex underlying reasons to conceive possible improvements. As part of its Strategic Trade and Supply Chain Analytics Initiative, Argonne National Laboratory supported a study of a subset of the European Union’s TARIC correlation table. The study included development of a methodology and an approach to rating the quality and relevance of individual correlations. The study was intended as a first step to engage the STC community in deflections and initiatives to improve the conception and use of correlations, and its conclusions illustrate the scope and complex nature of the challenges to overcome. This paper presents the two classification systems, analyzes the needs for correlation tables and the complex challenges associated with them, summarizes key findings, and proposes possible ways forward.

  19. A Distributed Flow Rate Control Algorithm for Networked Agent System with Multiple Coding Rates to Optimize Multimedia Data Transmission

    Directory of Open Access Journals (Sweden)

    Shuai Zeng

    2013-01-01

    Full Text Available With the development of wireless technologies, mobile communication applies more and more extensively in the various walks of life. The social network of both fixed and mobile users can be seen as networked agent system. At present, kinds of devices and access network technology are widely used. Different users in this networked agent system may need different coding rates multimedia data due to their heterogeneous demand. This paper proposes a distributed flow rate control algorithm to optimize multimedia data transmission of the networked agent system with the coexisting various coding rates. In this proposed algorithm, transmission path and upload bandwidth of different coding rate data between source node, fixed and mobile nodes are appropriately arranged and controlled. On the one hand, this algorithm can provide user nodes with differentiated coding rate data and corresponding flow rate. On the other hand, it makes the different coding rate data and user nodes networked, which realizes the sharing of upload bandwidth of user nodes which require different coding rate data. The study conducts mathematical modeling on the proposed algorithm and compares the system that adopts the proposed algorithm with the existing system based on the simulation experiment and mathematical analysis. The results show that the system that adopts the proposed algorithm achieves higher upload bandwidth utilization of user nodes and lower upload bandwidth consumption of source node.

  20. Visual information gain and task asymmetry interact in bimanual force coordination and control.

    Science.gov (United States)

    Hu, Xiaogang; Newell, Karl M

    2011-08-01

    This study examined the question of whether and how the influence of visual information on force coordination patterns is dependent on the settings of a task asymmetry constraint. In a bimanual isometric force experiment, the task asymmetry was manipulated via imposing different coefficients on the index finger forces such that the weighted sum of the finger forces matched the target force. The environmental constraint was quantified by the visual performance error and was manipulated through the change of visual gain (number of pixels on the screen representing the unit of force). The constraint arising from the individual was quantified by the bilateral coupling effect (i.e., symmetric force production) between hands. The results revealed improved performance in terms of lower variability and performance error and more complex total force structure with higher visual gain. The influence of visual gain on the force coordination pattern, however, was found to be dependent on the task coefficients imposed on the finger forces. Namely, the force sharing between hands became more symmetric with high visual gain only when the right finger force had the higher coefficient, and an error-compensatory strategy was evident with high gain only when symmetric coefficients were imposed on the two fingers. The findings support the proposition that the motor coordination and control patterns are organized by the interactive influence of different categories of constraints where the functional influence of the information provided is dependent on the motor output.

  1. Instrument Display Visual Angles for Conventional Aircraft and the MQ-9 Ground Control Station

    Science.gov (United States)

    Bendrick, Gregg A.; Kamine, Tovy Haber

    2008-01-01

    Aircraft instrument panels should be designed such that primary displays are in optimal viewing location to minimize pilot perception and response time. Human Factors engineers define three zones (i.e. "cones") of visual location: 1) "Easy Eye Movement" (foveal vision); 2) "Maximum Eye Movement" (peripheral vision with saccades), and 3) "Head Movement" (head movement required). Instrument display visual angles were measured to determine how well conventional aircraft (T-34, T-38, F- 15B, F-16XL, F/A-18A, U-2D, ER-2, King Air, G-III, B-52H, DC-10, B747-SCA) and the MQ-9 ground control station (GCS) complied with these standards, and how they compared with each other. Methods: Selected instrument parameters included: attitude, pitch, bank, power, airspeed, altitude, vertical speed, heading, turn rate, slip/skid, AOA, flight path, latitude, longitude, course, bearing, range and time. Vertical and horizontal visual angles for each component were measured from the pilot s eye position in each system. Results: The vertical visual angles of displays in conventional aircraft lay within the cone of "Easy Eye Movement" for all but three of the parameters measured, and almost all of the horizontal visual angles fell within this range. All conventional vertical and horizontal visual angles lay within the cone of "Maximum Eye Movement". However, most instrument vertical visual angles of the MQ-9 GCS lay outside the cone of "Easy Eye Movement", though all were within the cone of "Maximum Eye Movement". All the horizontal visual angles for the MQ-9 GCS were within the cone of "Easy Eye Movement". Discussion: Most instrument displays in conventional aircraft lay within the cone of "Easy Eye Movement", though mission-critical instruments sometimes displaced less important instruments outside this area. Many of the MQ-9 GCS systems lay outside this area. Specific training for MQ-9 pilots may be needed to avoid increased response time and potential error during flight.

  2. Study on the effective method to improving the coding visual effect of fractal image%改善分形图像编码视觉效果的有效方法研究

    Institute of Scientific and Technical Information of China (English)

    杨凤霞

    2012-01-01

    针对当前分形图像编码面临如何改善重建图像视觉效果的问题,利用局部图像的特点,采取自适应的分块方法与缩短编码时间的多种块分类技术相结合设计图像编码算法,该算法明显改善了图像编码视觉效果,编码时间缩短上千倍,具有快速实现分形图像编码之功效.%To improve the reconstructed coding visual effect of fractal image, a new image coding algorithm is developed using adaptive block method integrated with classification techniques for multiple types of blocks which can reduce the coding time. Using proposed coding algorithm, the coding visual effect is improved a lot and the coding time is reduced by thousands of times. Finally,a rapid fractal image coding effect can be realized.

  3. A Port-Hamiltonian Approach to Visual Servo Control of a Pick and Place System

    NARCIS (Netherlands)

    Dirksz, Daniel A.; Scherpen, Jacquelien M. A.; Steinbuch, Maarten

    In this paper, we take a port-Hamiltonian approach to address the problem of image-based visual servo control of a pick and place system. Through a coordinate transformation and a passive interconnection between mechanical system and camera dynamics we realize a closed-loop system that is

  4. Gaze Behavior in Basketball Shooting: Further Evidence for Online Visual Control

    Science.gov (United States)

    de Oliveira, Rita F.; Oudejans, Raoul R. D.; Beek, Peter J.

    2008-01-01

    The aim of the present study was to help resolve conflicting findings and interpretations regarding the visual control of basketball shooting by examining the looking behavior of 6 expert basketball players (3 with a low shooting style and 3 with a high shooting style) executing both free throws and jump shots. Based on previous findings, they…

  5. Self-Esteem, Locus of Control and Various Aspects of Psychopathology of Adults with Visual Impairments

    Science.gov (United States)

    Papadopoulos, Konstantinos; Paralikas, Theodosis; Barouti, Marialena; Chronopoulou, Elena

    2014-01-01

    The exploratory study presented in this article looks into the possible differences in psychosocial aspects (self-esteem and locus of control) and aspects of psychopathology (depression, anxiety, melancholia, asthenia, and mania) amongst sighted adults and adults with visual impairments. Moreover, the study aims to examine the possible…

  6. Postural Control in Young People with Visual Impairments and Various Risks of Falls

    Science.gov (United States)

    Sadowska, Dorota; Stemplewski, Rafal; Szeklicki, Robert

    2017-01-01

    Introduction: Early diagnosis of postural control deficiencies facilitates implementation of an individual rehabilitation plan to prevent falls. The aim of the study was to assess the risk of falling in individuals with visual impairments, and to compare performance-based and theoretical limits of stability in subjects with various risks of…

  7. Acute Caffeine Consumption Enhances the Executive Control of Visual Attention in Habitual Consumers

    Science.gov (United States)

    Brunye, Tad T.; Mahoney, Caroline R.; Lieberman, Harris R.; Giles, Grace E.; Taylor, Holly A.

    2010-01-01

    Recent work suggests that a dose of 200-400mg caffeine can enhance both vigilance and the executive control of visual attention in individuals with low caffeine consumption profiles. The present study seeks to determine whether individuals with relatively high caffeine consumption profiles would show similar advantages. To this end, we examined…

  8. Image-based visual servo control using the port-Hamiltonian Approach

    NARCIS (Netherlands)

    Muñoz Arias, Mauricio; El Hawwary, Mohamed; Scherpen, Jacquelien M.A.

    2015-01-01

    This work is devoted to an image-based visual servo control strategy for standard mechanical systems in the port-Hamiltonian framework. We utilize a change of variables that transforms the port-Hamiltonian system into one with constant mass-inertia matrix, and we use an interaction matrix that inclu

  9. Self-Esteem, Locus of Control and Various Aspects of Psychopathology of Adults with Visual Impairments

    Science.gov (United States)

    Papadopoulos, Konstantinos; Paralikas, Theodosis; Barouti, Marialena; Chronopoulou, Elena

    2014-01-01

    The exploratory study presented in this article looks into the possible differences in psychosocial aspects (self-esteem and locus of control) and aspects of psychopathology (depression, anxiety, melancholia, asthenia, and mania) amongst sighted adults and adults with visual impairments. Moreover, the study aims to examine the possible…

  10. Acute Caffeine Consumption Enhances the Executive Control of Visual Attention in Habitual Consumers

    Science.gov (United States)

    Brunye, Tad T.; Mahoney, Caroline R.; Lieberman, Harris R.; Giles, Grace E.; Taylor, Holly A.

    2010-01-01

    Recent work suggests that a dose of 200-400mg caffeine can enhance both vigilance and the executive control of visual attention in individuals with low caffeine consumption profiles. The present study seeks to determine whether individuals with relatively high caffeine consumption profiles would show similar advantages. To this end, we examined…

  11. Decoding Delay Controlled Completion Time Reduction in Instantly Decodable Network Coding

    KAUST Repository

    Douik, Ahmed

    2016-06-27

    For several years, the completion time and the decoding delay problems in Instantly Decodable Network Coding (IDNC) were considered separately and were thought to act completely against each other. Recently, some works aimed to balance the effects of these two important IDNC metrics but none of them studied a further optimization of one by controlling the other. This paper investigates the effect of controlling the decoding delay to reduce the completion time below its currently best-known solution in both perfect and imperfect feedback with persistent erasure channels. To solve the problem, the decodingdelay- dependent expressions of the users’ and overall completion times are derived in the complete feedback scenario. Although using such expressions to find the optimal overall completion time is NP-hard, the paper proposes two novel heuristics that minimizes the probability of increasing the maximum of these decoding-delay-dependent completion time expressions after each transmission through a layered control of their decoding delays. Afterward, the paper extends the study to the imperfect feedback scenario in which uncertainties at the sender affects its ability to anticipate accurately the decoding delay increase at each user. The paper formulates the problem in such environment and derives the expression of the minimum increase in the completion time. Simulation results show the performance of the proposed solutions and suggest that both heuristics achieves a lower mean completion time as compared to the best-known heuristics for the completion time reduction in perfect and imperfect feedback. The gap in performance becomes more significant as the erasure of the channel increases.

  12. Contributions of sensory coding and attentional control to individual differences in performance in spatial auditory selective attention tasks

    Directory of Open Access Journals (Sweden)

    Lengshi Dai

    2016-10-01

    Full Text Available Listeners with normal hearing thresholds differ in their ability to steer attention to whatever sound source is important. This ability depends on top-down executive control, which modulates the sensory representation of sound in cortex. Yet, this sensory representation also depends on the coding fidelity of the peripheral auditory system. Both of these factors may thus contribute to the individual differences in performance. We designed a selective auditory attention paradigm in which we could simultaneously measure envelope following responses (EFRs, reflecting peripheral coding, onset event-related potentials from the scalp (ERPs, reflecting cortical responses to sound, and behavioral scores. We performed two experiments that varied stimulus conditions to alter the degree to which performance might be limited due to fine stimulus details vs. due to control of attentional focus. Consistent with past work, in both experiments we find that attention strongly modulates cortical ERPs. Importantly, in Experiment I, where coding fidelity limits the task, individual behavioral performance correlates with subcortical coding strength (derived by computing how the EFR is degraded for fully masked tones compared to partially masked tones; however, in this experiment, the effects of attention on cortical ERPs were unrelated to individual subject performance. In contrast, in Experiment II, where sensory cues for segregation are robust (and thus less of a limiting factor on task performance, inter-subject behavioral differences correlate with subcortical coding strength. In addition, after factoring out the influence of subcortical coding strength, behavioral differences are also correlated with the strength of attentional modulation of ERPs. These results support the hypothesis that behavioral abilities amongst listeners with normal hearing thresholds can arise due to both subcortical coding differences and differences in attentional control, depending on

  13. Genetic Searching Algorithm for Optimal Runlength—Limited Codes with Error Control

    Institute of Scientific and Technical Information of China (English)

    RenQingsheng; YeZhongxing

    1997-01-01

    A genetic searching algorithm is presented to construct arbitrarily concatenatable block code with runlength(d,k)constraints.The code also has the ability to correct error during decoding.A similar eliminating operator and an anti-symbiotic operator are suggested to improve the efficiency of the algorithm.

  14. HEIGHT CODE TABLES FOR USE WITH AIR TRAFFIC CONTROL RADAR BEACON SYSTEM

    Science.gov (United States)

    The Seventh Communications Division of the International Civil Aviation Organization ( ICAO ) has recommended the adoption of a digital code for...characteristic; (5) Height transmission with respect to a fixed datum of 1013.2 millibars (29.92 inches of mercury). The code, as recommended by ICAO , is

  15. Audio-visual feedback improves the BCI performance in the navigational control of a humanoid robot.

    Science.gov (United States)

    Tidoni, Emmanuele; Gergondet, Pierre; Kheddar, Abderrahmane; Aglioti, Salvatore M

    2014-01-01

    Advancement in brain computer interfaces (BCI) technology allows people to actively interact in the world through surrogates. Controlling real humanoid robots using BCI as intuitively as we control our body represents a challenge for current research in robotics and neuroscience. In order to successfully interact with the environment the brain integrates multiple sensory cues to form a coherent representation of the world. Cognitive neuroscience studies demonstrate that multisensory integration may imply a gain with respect to a single modality and ultimately improve the overall sensorimotor performance. For example, reactivity to simultaneous visual and auditory stimuli may be higher than to the sum of the same stimuli delivered in isolation or in temporal sequence. Yet, knowledge about whether audio-visual integration may improve the control of a surrogate is meager. To explore this issue, we provided human footstep sounds as audio feedback to BCI users while controlling a humanoid robot. Participants were asked to steer their robot surrogate and perform a pick-and-place task through BCI-SSVEPs. We found that audio-visual synchrony between footsteps sound and actual humanoid's walk reduces the time required for steering the robot. Thus, auditory feedback congruent with the humanoid actions may improve motor decisions of the BCI's user and help in the feeling of control over it. Our results shed light on the possibility to increase robot's control through the combination of multisensory feedback to a BCI user.

  16. Three-dimensional visualization and control of electronic warfare (EW) payloads

    Science.gov (United States)

    Kirsch, Patricia; Tremper, David; Cortesi, Roger

    2008-04-01

    The proliferation of unmanned vehicles carrying tactical payloads in the battle-space has accelerated the need for user-friendly visualization with graphical interfaces to provide remote command and control. Often these platforms and payloads receive their control functions from command centers located half a world away via satellite communications. Operators require situational awareness tools capable of graphically presenting the remote battlefield asset positions and collected sensor data. Often these systems use 2D software mapping tools in conjunction with video for real time situational awareness. The Special Projects Group (SPG) in the Tactical Electronic Warfare Division of the U.S. Naval Research Laboratory has been developing an operator control interface called the Jammer Control Station (JCS) to provide 3D battle-space visualization with built-in, remote EW payload command and control (C2) capabilities. The JCS interface presents the operator with graphic depictions of both the platforms' states and the RF environment. Text based messaging between the JCS and the EW payload reduces the impact of the system on the available bandwidth. This paper will discuss the use of the SIMDIS 3-D visualization tool as a real-time command and control interface for electronic warfare (EW) payloads.

  17. Handwriting performance in the absence of visual control in writer's cramp patients: initial observations.

    Science.gov (United States)

    Chakarov, Vihren; Hummel, Sibylla; Losch, Florian; Schulte-Mönting, Jürgen; Kristeva, Rumyana

    2006-04-04

    The present study was aimed at investigating the writing parameters of writer's cramp patients and control subjects during handwriting of a test sentence in the absence of visual control. Eight right-handed patients with writer's cramp and eight healthy volunteers as age-matched control subjects participated in the study. The experimental task consisted in writing a test sentence repeatedly for fifty times on a pressure-sensitive digital board. The subject did not have visual control on his handwriting. The writing performance was stored on a PC and analyzed off-line. During handwriting all patients developed a typical dystonic limb posture and reported an increase in muscular tension along the experimental session. The patients were significantly slower than the controls, with lower mean vertical pressure of the pen tip on the paper and they could not reach the endmost letter of the sentence in the given time window. No other handwriting parameter differences were found between the two groups. Our findings indicate that during writing in the absence of visual feedback writer's cramp patients are slower and could not reach the endmost letter of the test sentence, but their level of automatization is not impaired and writer's cramp handwriting parameters are similar to those of the controls except for even lower vertical pressure of the pen tip on the paper, which is probably due to a changed strategy in such experimental conditions.

  18. Handwriting performance in the absence of visual control in writer's cramp patients: Initial observations

    Directory of Open Access Journals (Sweden)

    Losch Florian

    2006-04-01

    Full Text Available Abstract Background The present study was aimed at investigating the writing parameters of writer's cramp patients and control subjects during handwriting of a test sentence in the absence of visual control. Methods Eight right-handed patients with writer's cramp and eight healthy volunteers as age-matched control subjects participated in the study. The experimental task consisted in writing a test sentence repeatedly for fifty times on a pressure-sensitive digital board. The subject did not have visual control on his handwriting. The writing performance was stored on a PC and analyzed off-line. Results During handwriting all patients developed a typical dystonic limb posture and reported an increase in muscular tension along the experimental session. The patients were significantly slower than the controls, with lower mean vertical pressure of the pen tip on the paper and they could not reach the endmost letter of the sentence in the given time window. No other handwriting parameter differences were found between the two groups. Conclusion Our findings indicate that during writing in the absence of visual feedback writer's cramp patients are slower and could not reach the endmost letter of the test sentence, but their level of automatization is not impaired and writer's cramp handwriting parameters are similar to those of the controls except for even lower vertical pressure of the pen tip on the paper, which is probably due to a changed strategy in such experimental conditions.

  19. Discrete neurochemical coding of distinguishable motivational processes: insights from nucleus accumbens control of feeding.

    Science.gov (United States)

    Baldo, Brian A; Kelley, Ann E

    2007-04-01

    The idea that nucleus accumbens (Acb) dopamine transmission contributes to the neural mediation of reward, at least in a general sense, has achieved wide acceptance. Nevertheless, debate remains over the precise nature of dopamine's role in reward and even over the nature of reward itself. In the present article, evidence is reviewed from studies of food intake, feeding microstructure, instrumental responding for food reinforcement, and dopamine efflux associated with feeding, which suggests that reward processing in the Acb is best understood as an interaction among distinct processes coded by discrete neurotransmitter systems. In agreement with several theories of Acb dopamine function, it is proposed here that allocation of motor effort in seeking food or food-associated conditioned stimuli can be dissociated from computations relevant to the hedonic evaluation of food during the consummatory act. The former appears to depend upon Acb dopamine transmission and the latter upon striatal opioid peptide release. Moreover, dopamine transmission may play a role in 'stamping in' associations between motor acts and goal attainment and perhaps also neural representations corresponding to rewarding outcomes. Finally, evidence is reviewed that amino acid transmission specifically in the Acb shell acts as a central 'circuit breaker' to flexibly enable or terminate the consummatory act, via descending connections to hypothalamic feeding control systems. The heuristic framework outlined above may help explain why dopamine-compromising manipulations that strongly diminish instrumental goal-seeking behaviors leave consummatory activity relatively unaffected.

  20. Russian Army Mat as a Code System Controlling Behaviour in the Russian army

    Directory of Open Access Journals (Sweden)

    Vadim Mikhailin

    2004-09-01

    Full Text Available This text is to be a shortened, restructured and based on somewhat another factological foundation version of my article “Russkii mat kak muzhskoi obstsennyi kod: problema proiskhozhdeniia i evoliutsiia statusa”, published in # 43 of Novoe Literaturnoe Obozrenie. Tracing the genesis of mat to the specific modes of behaviour, peculiar to the archaic male warrior bands, I’m going to show that the military milieu (and some other, structurally close to it social strata, has always been – and remain – absolutely adequate for the mat speaking. Moreover, mat has always carried on within these strata rather specific function connected with creating of one’s identity as a military, and its use offers various and sometimes the only possible means of impact at one’s equal or subordinate (or even superior. As a matter of fact, mat is a basis for a whole code system, controlling different military behaviour practices. The problems of the freshers’ adaptation and of the national specificities in the late Soviet and modern Russian army are to be considered with special respect.

  1. SCALE: A modular code system for performing standardized computer analyses for licensing evaluation: Control modules C4, C6

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    This Manual represents Revision 5 of the user documentation for the modular code system referred to as SCALE. The history of the SCALE code system dates back to 1969 when the current Computational Physics and Engineering Division at Oak Ridge National Laboratory (ORNL) began providing the transportation package certification staff at the U. S. Atomic Energy Commission with computational support in the use of the new KENO code for performing criticality safety assessments with the statistical Monte Carlo method. From 1969 to 1976 the certification staff relied on the ORNL staff to assist them in the correct use of codes and data for criticality, shielding, and heat transfer analyses of transportation packages. However, the certification staff learned that, with only occasional use of the codes, it was difficult to become proficient in performing the calculations often needed for an independent safety review. Thus, shortly after the move of the certification staff to the U.S. Nuclear Regulatory Commission (NRC), the NRC staff proposed the development of an easy-to-use analysis system that provided the technical capabilities of the individual modules with which they were familiar. With this proposal, the concept of the Standardized Computer Analyses for Licensing Evaluation (SCALE) code system was born. This volume is part of the manual related to the control modules for the newest updated version of this computational package.

  2. Evaluating on-line control of goal-directed arm movement while standing in virtual visual environment

    OpenAIRE

    Martin, Olivier; Julian, Benjamin; Boissieux, Laurence; Gascuel, Jean-Dominique; Prablanc, Claude

    2002-01-01

    International audience; The control of visually guided movement has been showed to be optimised when motor programming quickly integrated the visual information to update on-going motor commands. The purpose of this study was to verify this proposition for movement executed in virtual visual environment (VE), by exploring the effect of immersion on the on-line visuomotor control of goal-directed arm movement. Six subjects participated in the experiment, in which hand reaching toward a station...

  3. Processing of visual information compromises the ability of older adults to control novel fine motor tasks.

    Science.gov (United States)

    Baweja, Harsimran S; Kwon, MinHyuk; Onushko, Tanya; Wright, David L; Corcos, Daniel M; Christou, Evangelos A

    2015-12-01

    We performed two experiments to determine whether amplified motor output variability and compromised processing of visual information in older adults impair short-term adaptations when learning novel fine motor tasks. In Experiment 1, 12 young and 12 older adults underwent training to learn how to accurately trace a sinusoidal position target with abduction-adduction of their index finger. They performed 48 trials, which included 8 blocks of 6 trials (the last trial of each block was performed without visual feedback). Afterward, subjects received an interference task (watched a movie) for 60 min. We tested retention by asking subjects to perform the sinusoidal task (5 trials) with and without visual feedback. In Experiment 2, 12 young and 10 older adults traced the same sinusoidal position target with their index finger and ankle at three distinct visual angles (0.25°, 1° and 5.4°). In Experiment 1, the movement error and variability were greater for older adults during the visual feedback trials when compared with young adults. In contrast, during the no-vision trials, age-associated differences in movement error and variability were ameliorated. Short-term adaptations in learning the sinusoidal task were similar for young and older adults. In Experiment 2, lower amount of visual feedback minimized the age-associated differences in movement variability for both the index finger and ankle movements. We demonstrate that although short-term adaptations are similar for young and older adults, older adults do not process visual information as well as young adults and that compromises their ability to control novel fine motor tasks during acquisition, which could influence long-term retention and transfer.

  4. Selective use of visual information signaling objects' center of mass for anticipatory control of manipulative fingertip forces.

    Science.gov (United States)

    Salimi, Iran; Frazier, Wendy; Reilmann, Ralf; Gordon, Andrew M

    2003-05-01

    The present study examines whether visual information indicating the center of mass (CM) of an object can be used for the appropriate scaling of fingertip forces at each digit during precision grip. In separate experiments subjects lifted an object with various types of visual cues concerning the CM location several times and then rotated and lifted it again to determine whether the visual cues signaling the new location of the CM could be used to appropriately scale the fingertip forces. Specifically, subjects had either no visual cues, visual instructional cues (i.e., an indicator) or visual geometric cues where the longer axis of the object indicated the CM. When no visual cues were provided, subjects were unable to appropriately scale the load forces at each digit following rotation despite their knowledge of the new weight distribution. When visual cues regarding the CM location were provided, the nature of the visual cues determined their effectiveness in retrieval of internal representations underlying the anticipatory scaling of fingertip forces. Specifically, when subjects were provided with visual instructional information, they were unable to appropriately scale the forces. More appropriate scaling of the load forces occurred when the visual cues were ecologically meaningful, i.e., when the shape of the object indicated the CM location. We suggest that visual instructional cues do not have access to the implicit processes underlying dynamic force control, whereas visual geometric cues can be used for the retrieval of the internal representation related to CM for appropriate partitioning of the forces in each digit.

  5. Active control of the visual field in the starfish Acanthaster planci.

    Science.gov (United States)

    Beer, S; Wentzel, C; Petie, R; Garm, A

    2016-10-01

    Photoreception in echinoderms has been studied for several years with a focus on the dermal photoreceptors of echinoids. Even though spatial vision has been proposed for this dermal photosystem, by far the most advanced system is found in a number of asteroids where an unpaired tube foot at the tip of each arm carries a proper eye, also known as the optical cushion. The eyes resemble compound eyes, except for the lack of true optics, and they typically have between 50 and 250 ommatidia each. These eyes have been known for two centuries but no visually guided behaviors were known in starfish until recently when it was shown that both Linckia laevigata and Acanthaster planci navigate their coral reef habitat using vision. Here we investigate the visual system of A. planci and find that they have active control of their visual field. The distalmost tube foot holding the eye is situated on a movable knob, which bends to adjust the vertical angle of the visual field. On the leading arms the visual field is directed 33° above the horizon, whereas the eyes on the trailing arms are directed 44° above horizontal on average. When the animal traverses an obstacle the knob bends and counteracts most of the arm bending. Further, we examined a previously described behavior, rhythmic arm elevation, and suggest that it allows the animal to scan the surroundings while preventing photoreceptor adaptation and optimizing image contrast. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. A Novel Optical Morse Code-Based Electronic Lock Using the Ambient Light Sensor and Fuzzy Controller

    Directory of Open Access Journals (Sweden)

    Chin-Tan Lee

    2017-02-01

    Full Text Available In this work, a novel electronic lock that can encode and decode optical signals, modulated using Morse code conventions, was developed to build a smart home security system based on the Internet of Things (IoT. There are five topics of interest in this research: (1 optical Morse code encoder; (2 optical Morse code decoder; (3 ambient light sensor circuit; (4 fuzzy controller; (5 cloud monitoring system. We take advantage of the light-emitting components as the encoder, which are readily available in hand-held mobile devices (e.g., Smart phones and photoresistors and a microcontroller as the decoder. By Wi-Fi transferring, even without a personal computer, real-time information about this lock can be uploaded to the cloud service platform, and helps users to ensure home safety on the remote monitoring system. By using the ambient light sensor and fuzzy controller in this novel optical Morse code-based electronic lock, experimental results show that the reliability of this system is much improved from 65% to 100%. That means that it is highly resistant to different illumination conditions in the work environment, and therefore all functions, including coding, emitting, receiving, decoding, uploading and cloud monitoring, can work well. Furthermore, besides the convenience and cost reduction, by incorporating traditional keys into smart phones, as a consumer electronics, our proposed system is suitable for users of all ages because of a user-friendly operation interface.

  7. Research on flight stability performance of rotor aircraft based on visual servo control method

    Science.gov (United States)

    Yu, Yanan; Chen, Jing

    2016-11-01

    control method based on visual servo feedback is proposed, which is used to improve the attitude of a quad-rotor aircraft and to enhance its flight stability. Ground target images are obtained by a visual platform fixed on aircraft. Scale invariant feature transform (SIFT) algorism is used to extract image feature information. According to the image characteristic analysis, fast motion estimation is completed and used as an input signal of PID flight control system to realize real-time status adjustment in flight process. Imaging tests and simulation results show that the method proposed acts good performance in terms of flight stability compensation and attitude adjustment. The response speed and control precision meets the requirements of actual use, which is able to reduce or even eliminate the influence of environmental disturbance. So the method proposed has certain research value to solve the problem of aircraft's anti-disturbance.

  8. Visual Control for Unicycle-Like Mobile Robots Formation Under the Leader-Follower Scheme

    Directory of Open Access Journals (Sweden)

    Bugarin-Carlos Eusebio

    2014-10-01

    Full Text Available This paper describes a visual control proposal for the formation of unicycle-like mobile robots under the leader-follower scheme. It is considered a single fixed camera observing the robots workspace that, in terms of the processed information, can be shared by both the leader robot and the follower robot. This would enable the implementation of this proposal to be performed by centralized or decentralized control strategies. For the purpose of simplifying the analysis, it is also considered that the image plane is parallel to the robots motion plane. The formation objective is established directly in image space and the proposed visual controller does not depend explicitly on the vision system parameters (extrinsic or intrinsic; which together represents the main contribution of this paper. Finally, also as an important part of this work, to validate the proposed theory satisfactory experiments using a real-time and high-speed vision system are detailed.

  9. Lighting energy savings potential of split-pane electrochromic windows controlled for daylighting with visual comfort

    Energy Technology Data Exchange (ETDEWEB)

    Software, Anyhere; Fernandes, Luis; Lee, Eleanor; Ward, Greg

    2013-03-15

    A simulation study was conducted to evaluate lighting energy savings of split-pane electrochromic (EC) windows controlled to satisfy key visual comfort parameters. Using the Radiance lighting simulation software, interior illuminance and luminance levels were computed for a south-facing private office illuminated by a window split into two independently-controlled EC panes. The transmittance of these was optimized hourly for a workplane illuminance target while meeting visual comfort constraints, using a least-squares algorithm with linear inequality constraints. Blinds were successively deployed until visual comfort criteria were satisfied. The energy performance of electrochromics proved to be highly dependent on how blinds were controlled. With hourly blind position adjustments, electrochromics showed significantly higher (62percent and 53percent, respectively without and with overhang) lighting energy consumption than clear glass. With a control algorithm designed to better approximate realistic manual control by an occupant, electrochromics achieved significant savings (48percent and 37percent, respectively without and with overhang). In all cases, energy consumption decreased when the workplace illuminance target was increased. In addition, the fraction of time during which the occupant had an unobstructed view of the outside was significantly greater with electrochromics: 10 months out of the year versus a handful of days for the reference case.

  10. A General Framework for Development of the Cortex-like Visual Object Recognition System: Waves of Spikes, Predictive Coding and Universal Dictionary of Features

    CERN Document Server

    Tarasenko, Sergey S

    2011-01-01

    This study is focused on the development of the cortex-like visual object recognition system. We propose a general framework, which consists of three hierarchical levels (modules). These modules functionally correspond to the V1, V4 and IT areas. Both bottom-up and top-down connections between the hierarchical levels V4 and IT are employed. The higher the degree of matching between the input and the preferred stimulus, the shorter the response time of the neuron. Therefore information about a single stimulus is distributed in time and is transmitted by the waves of spikes. The reciprocal connections and waves of spikes implement predictive coding: an initial hypothesis is generated on the basis of information delivered by the first wave of spikes and is tested with the information carried by the consecutive waves. The development is considered as extraction and accumulation of features in V4 and objects in IT. Once stored a feature can be disposed, if rarely activated. This cause update of feature repository....

  11. Real-time gesture recognition by learning and selective control of visual interest points.

    Science.gov (United States)

    Kirishima, Toshiyuki; Sato, Kosuke; Chihara, Kunihiro

    2005-03-01

    For the real-time recognition of unspecified gestures by an arbitrary person, a comprehensive framework is presented that addresses two important problems in gesture recognition systems: selective attention and processing frame rate. To address the first problem, we propose the Quadruple Visual Interest Point Strategy. No assumptions are made with regard to scale or rotation of visual features, which are computed from dynamically changing regions of interest in a given image sequence. In this paper, each of the visual features is referred to as a visual interest point, to which a probability density function is assigned, and the selection is carried out. To address the second problem, we developed a selective control method to equip the recognition system with self-load monitoring and controlling functionality. Through evaluation experiments, we show that our approach provides robust recognition with respect to such factors as type of clothing, type of gesture, extent of motion trajectories, and individual differences in motion characteristics. In order to indicate the real-time performance and utility aspects of our approach, a gesture video system is developed that demonstrates full video-rate interaction with displayed image objects.

  12. SUENTP code simulations of scale-up and economic evaluation of non-thermal plasma technology for exhaust gas emission control of coal fired power plants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S.J.; Chang, J.-S. [McMaster University, Hamilton, ON (Canada). Dept. of Engineering Physics

    1998-07-01

    Computer code (SUENTP) to predict scale up and economic evaluation of several eligible non-thermal plasma processes for air pollution control - electron beam process, pulsed corona process, and corona radical shower process - was developed for a commercialized power plant. This code was written by spread sheet type MS Excel with visual basic for application and comprise data input procedure, scale-up (design) procedure, economic calculation procedure, and output procedure. Data obtained from pilot plant tests are input with general data so that they might be led to the conceptual design data of commercial plants by scale-up procedure. In the next economic evaluation procedure, the total capital investment and the total annual cost. The total capital investment comes into the indirect annual cost as the item of capital recovery. The levelized cost and the levelized busbar cost could be shown in the output table. An example calculation was presented to evaluate the cost of three non-thermal systems and the results were compared with a conventional wet-scrubber/selective catalytic reduction combined system. 13 refs., 3 figs., 3 tabs.

  13. Visual servo walking control for humanoids with finite-time convergence and smooth robot velocities

    Science.gov (United States)

    Delfin, Josafat; Becerra, Hector M.; Arechavaleta, Gustavo

    2016-07-01

    In this paper, we address the problem of humanoid locomotion guided from information of a monocular camera. The goal of the robot is to reach a desired location defined in terms of a target image, i.e., a positioning task. The proposed approach allows us to introduce a desired time to complete the positioning task, which is advantageous in contrast to the classical exponential convergence. In particular, finite-time convergence is achieved while generating smooth robot velocities and considering the omnidirectional waking capability of the robot. In addition, we propose a hierarchical task-based control scheme, which can simultaneously handle the visual positioning and the obstacle avoidance tasks without affecting the desired time of convergence. The controller is able to activate or inactivate the obstacle avoidance task without generating discontinuous velocity references while the humanoid is walking. Stability of the closed loop for the two task-based control is demonstrated theoretically even during the transitions between the tasks. The proposed approach is generic in the sense that different visual control schemes are supported. We evaluate a homography-based visual servoing for position-based and image-based modalities, as well as for eye-in-hand and eye-to-hand configurations. The experimental evaluation is performed with the humanoid robot NAO.

  14. Line Tracking Control of a Two-Wheeled Mobile Robot Using Visual Feedback

    Directory of Open Access Journals (Sweden)

    G. H. Lee

    2013-03-01

    Full Text Available This article presents the development and control of a two‐wheeled mobile robot as the base of a human carrier for an amusement/transportation vehicle. The robot has a combined structure of two systems: a line tracking mobile robot and an inverted pendulum system that maintains balance while following a line on the floor. The mobile robot is purposely designed to carry a human operator or humanoid arms. The robot has the capability to follow the line on the floor using visual feedback, as well as maintaining its balance on two wheels. A visual servoing technique allows the robot to follow the line on the floor captured by a camera as the desired trajectory. Controllers are designed to have good line tracking and balancing performance using sensor fusion techniques. Experimental studies involving the robot following a line demonstrate the feasibility of it being an amusement vehicle.

  15. Line Tracking Control of a Two-Wheeled Mobile Robot Using Visual Feedback

    Directory of Open Access Journals (Sweden)

    G. H. Lee

    2013-03-01

    Full Text Available This article presents the development and control of a two-wheeled mobile robot as the base of a human carrier for an amusement/transportation vehicle. The robot has a combined structure of two systems: a line tracking mobile robot and an inverted pendulum system that maintains balance while following a line on the floor. The mobile robot is purposely designed to carry a human operator or humanoid arms. The robot has the capability to follow the line on the floor using visual feedback, as well as maintaining its balance on two wheels. A visual servoing technique allows the robot to follow the line on the floor captured by a camera as the desired trajectory. Controllers are designed to have good line tracking and balancing performance using sensor fusion techniques. Experimental studies involving the robot following a line demonstrate the feasibility of it being an amusement vehicle.

  16. The Next Generation of Ground Operations Command and Control; Scripting in C no. and Visual Basic

    Science.gov (United States)

    Ritter, George; Pedoto, Ramon

    2010-01-01

    Scripting languages have become a common method for implementing command and control solutions in space ground operations. The Systems Test and Operations Language (STOL), the Huntsville Operations Support Center (HOSC) Scripting Language Processor (SLP), and the Spacecraft Control Language (SCL) offer script-commands that wrap tedious operations tasks into single calls. Since script-commands are interpreted, they also offer a certain amount of hands-on control that is highly valued in space ground operations. Although compiled programs seem to be unsuited for interactive user control and are more complex to develop, Marshall Space flight Center (MSFC) has developed a product called the Enhanced and Redesign Scripting (ERS) that makes use of the graphical and logical richness of a programming language while offering the hands-on and ease of control of a scripting language. ERS is currently used by the International Space Station (ISS) Payload Operations Integration Center (POIC) Cadre team members. ERS integrates spacecraft command mnemonics, telemetry measurements, and command and telemetry control procedures into a standard programming language, while making use of Microsoft's Visual Studio for developing Visual Basic (VB) or C# ground operations procedures. ERS also allows for script-style user control during procedure execution using a robust graphical user input and output feature. The availability of VB and C# programmers, and the richness of the languages and their development environment, has allowed ERS to lower our "script" development time and maintenance costs at the Marshall POIC.

  17. Behavioural system identification of visual flight speed control in Drosophila melanogaster.

    Science.gov (United States)

    Rohrseitz, Nicola; Fry, Steven N

    2011-02-06

    Behavioural control in many animals involves complex mechanisms with intricate sensory-motor feedback loops. Modelling allows functional aspects to be captured without relying on a description of the underlying complex, and often unknown, mechanisms. A wide range of engineering techniques are available for modelling, but their ability to describe time-continuous processes is rarely exploited to describe sensory-motor control mechanisms in biological systems. We performed a system identification of visual flight speed control in the fruitfly Drosophila, based on an extensive dataset of open-loop responses previously measured under free flight conditions. We identified a second-order under-damped control model with just six free parameters that well describes both the transient and steady-state characteristics of the open-loop data. We then used the identified control model to predict flight speed responses after a visual perturbation under closed-loop conditions and validated the model with behavioural measurements performed in free-flying flies under the same closed-loop conditions. Our system identification of the fruitfly's flight speed response uncovers the high-level control strategy of a fundamental flight control reflex without depending on assumptions about the underlying physiological mechanisms. The results are relevant for future investigations of the underlying neuromotor processing mechanisms, as well as for the design of biomimetic robots, such as micro-air vehicles.

  18. Visual illusions, delayed grasping, and memory: no shift from dorsal to ventral control.

    Science.gov (United States)

    Franz, V H; Hesse, C; Kollath, S

    2009-05-01

    We tested whether a delay between stimulus presentation and grasping leads to a shift from dorsal to ventral control of the movement, as suggested by the perception-action theory of Milner and Goodale (Milner, A.D., & Goodale, M.A. (1995). The visual brain in action. Oxford: Oxford University Press.). In this theory the dorsal cortical stream has a short memory, such that after a few seconds the dorsal information is decayed and the action is guided by the ventral stream. Accordingly, grasping should become responsive to certain visual illusions after a delay (because only the ventral stream is assumed to be deceived by these illusions). We used the Müller-Lyer illusion, the typical illusion in this area of research, and replicated the increase of the motor illusion after a delay. However, we found that this increase is not due to memory demands but to the availability of visual feedback during movement execution which leads to online corrections of the movement. Because such online corrections are to be expected if the movement is guided by one single representation of object size, we conclude that there is no evidence for a shift from dorsal to ventral control in delayed grasping of the Müller-Lyer illusion. We also performed the first empirical test of a critique Goodale (Goodale, M.A. (2006, October 27). Visual duplicity: Action without perception in the human visual system. The XIV. Kanizsa lecture, Triest, Italy.) raised against studies finding illusion effects in grasping: Goodale argued that these studies used methods that lead to unnatural grasping which is guided by the ventral stream. Therefore, these studies might never have measured the dorsal stream, but always the ventral stream. We found clear evidence against this conjecture.

  19. Research on Visual Simulation of UAV Formation Flight Control Based on Vega

    Directory of Open Access Journals (Sweden)

    Li Teng

    2015-01-01

    Full Text Available This paper proposes a control method of UAV formation reconfiguration, and accomplishes simulation of the transformation of UAV formation from a defensive formation to an offensive one using MATLAB/Simulink. Then, a visual simulation platform is built to display the simulation process in the form of animation and make the results more intuitive. The platform is built by means of MFC, Vega API and MATLAB engine.

  20. Progress in animation of an EMA-controlled tongue model for acoustic-visual speech synthesis

    CERN Document Server

    Steiner, Ingmar

    2012-01-01

    We present a technique for the animation of a 3D kinematic tongue model, one component of the talking head of an acoustic-visual (AV) speech synthesizer. The skeletal animation approach is adapted to make use of a deformable rig controlled by tongue motion capture data obtained with electromagnetic articulography (EMA), while the tongue surface is extracted from volumetric magnetic resonance imaging (MRI) data. Initial results are shown and future work outlined.

  1. Survey of Visual Control Bionics%视觉仿生控制研究综述

    Institute of Scientific and Technical Information of China (English)

    毛晓波; 陈铁军

    2013-01-01

    借鉴生物头眼协调运动灵活改变视线的神经控制机理构建智能仿生眼是机器人视觉控制研究的新热点.本综述分析了灵长类动物眼球运动的特点及其利用价值,从视觉仿生控制的视角,对国内外仿生机器眼的研究现状、存在的问题和发展趋势做了概括和总结.就利用生理学、仿生学和控制理论等多学科交叉融合的方法开展研究,针对多自由度双目头颈运动建模、机器人3D头眼协调运动控制、视觉偏差补偿算法以及视觉跟踪模式自适应切换策略等视觉控制难题,进行了讨论和展望.%Developing intelligent biomimetic eye is a new hot issue in the domain of robot visual control, which is based on neurophysiological mechanism of biological coordinated head-eye movement during gaze shift. In this work, oculomotor characteristics of primates and its utility values were reviewed, and next, the worldwide research status and development direction of biomimetic eye from the view of visual control were summarized. Some new bionic ideas and policies were given as well, such as making use of physiology, bionics, control theory and interdisciplinary study to explore multi-degree-of-freedom binocular biomimetic eye model, 3D head-eye coordinated control method, robot visual error compensation algorithms and adaptive patterns switching strategy of robot visual tracking.

  2. Effect of visual field locus and oscillation frequencies on posture control in an ecological environment.

    Science.gov (United States)

    Piponnier, Jean-Claude; Hanssens, Jean-Marie; Faubert, Jocelyn

    2009-01-14

    To examine the respective roles of central and peripheral vision in the control of posture, body sway amplitude (BSA) and postural perturbations (given by velocity root mean square or vRMS) were calculated in a group of 19 healthy young adults. The stimulus was a 3D tunnel, either static or moving sinusoidally in the anterior-posterior direction. There were nine visual field conditions: four central conditions (4, 7, 15, and 30 degrees); four peripheral conditions (central occlusions of 4, 7, 15, and 30 degrees); and a full visual field condition (FF). The virtual tunnel respected all the aspects of a real physical tunnel (i.e., stereoscopy and size increase with proximity). The results show that, under static conditions, central and peripheral visual fields appear to have equal importance for the control of stance. In the presence of an optic flow, peripheral vision plays a crucial role in the control of stance, since it is responsible for a compensatory sway, whereas central vision has an accessory role that seems to be related to spatial orientation.

  3. Finite-time tracking control for multiple non-holonomic mobile robots based on visual servoing

    Science.gov (United States)

    Ou, Meiying; Li, Shihua; Wang, Chaoli

    2013-12-01

    This paper investigates finite-time tracking control problem of multiple non-holonomic mobile robots via visual servoing. It is assumed that the pinhole camera is fixed to the ceiling, and camera parameters are unknown. The desired reference trajectory is represented by a virtual leader whose states are available to only a subset of the followers, and the followers have only interaction. First, the camera-objective visual kinematic model is introduced by utilising the pinhole camera model for each mobile robot. Second, a unified tracking error system between camera-objective visual servoing model and desired reference trajectory is introduced. Third, based on the neighbour rule and by using finite-time control method, continuous distributed cooperative finite-time tracking control laws are designed for each mobile robot with unknown camera parameters, where the communication topology among the multiple mobile robots is assumed to be a directed graph. Rigorous proof shows that the group of mobile robots converges to the desired reference trajectory in finite time. Simulation example illustrates the effectiveness of our method.

  4. Effects of the AMPA antagonist ZK 200775 on visual function: a randomized controlled trial.

    Directory of Open Access Journals (Sweden)

    Richard Bergholz

    Full Text Available BACKGROUND: ZK 200775 is an antagonist at the alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA receptor and had earned attention as a possible neuroprotective agent in cerebral ischemia. Probands receiving the agent within phase I trials reported on an alteration of visual perception. In this trial, the effects of ZK 200775 on the visual system were analyzed in detail. METHODOLOGY: In a randomised controlled trial we examined eyes and vision before and after the intravenous administration of two different doses of ZK 200775 and placebo. There were 3 groups of 6 probands each: Group 1 recieved 0.03 mg/kg/h, group 2 0.75 mg/kg/h of ZK 200775, the control group received 0.9% sodium chloride solution. Probands were healthy males aged between 57 and 69 years. The following methods were applied: clinical examination, visual acuity, ophthalmoscopy, colour vision, rod absolute threshold, central visual field, pattern-reversal visual evoked potentials (pVEP, ON-OFF and full-field electroretinogram (ERG. PRINCIPAL FINDINGS: No effect of ZK 200775 was seen on eye position or motility, stereopsis, pupillary function or central visual field testing. Visual acuity and dark vision deteriorated significantly in both treated groups. Color vision was most remarkably impaired. The dark-adapted ERG revealed a reduction of oscillatory potentials (OP and partly of the a- and b-wave, furthermore an alteration of b-wave morphology and an insignificantly elevated b/a-ratio. Cone-ERG modalities showed decreased amplitudes and delayed implicit times. In the ON-OFF ERG the ON-answer amplitudes increased whereas the peak times of the OFF-answer were reduced. The pattern VEP exhibited lower amplitudes and prolonged peak times. CONCLUSIONS: The AMPA receptor blockade led to a strong impairment of typical OFF-pathway functions like color vision and the cone ERG. On the other hand the ON-pathway as measured by dark vision and the scotopic ERG was affected as well

  5. Visual processing of optic flow and motor control in the human posterior cingulate sulcus.

    Science.gov (United States)

    Field, David T; Inman, Laura A; Li, Li

    2015-10-01

    Previous studies have shown that the human posterior cingulate contains a visual processing area selective for optic flow (CSv). However, other studies performed in both humans and monkeys have identified a somatotopic motor region at the same location (CMA). Taken together, these findings suggested the possibility that the posterior cingulate contains a single visuomotor integration region. To test this idea we used fMRI to identify both visual and motor areas of the posterior cingulate in the same brains and to test the activity of those regions during a visuomotor task. Results indicated that rather than a single visuomotor region the posterior cingulate contains adjacent but separate motor and visual regions. CSv lies in the fundus of the cingulate sulcus, while CMA lies in the dorsal bank of the sulcus, slightly superior in terms of stereotaxic coordinates. A surprising and novel finding was that activity in CSv was suppressed during the visuomotor task, despite the visual stimulus being identical to that used to localize the region. This may provide an important clue to the specific role played by this region in the utilization of optic flow to control self-motion.

  6. Knowledge Discovery for Smart Grid Operation, Control, and Situation Awareness -- A Big Data Visualization Platform

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Yi; Jiang, Huaiguang; Zhang, Yingchen; Zhang, Jun Jason; Gao, Tianlu; Muljadi, Eduard

    2016-11-21

    In this paper, a big data visualization platform is designed to discover the hidden useful knowledge for smart grid (SG) operation, control and situation awareness. The spawn of smart sensors at both grid side and customer side can provide large volume of heterogeneous data that collect information in all time spectrums. Extracting useful knowledge from this big-data poll is still challenging. In this paper, the Apache Spark, an open source cluster computing framework, is used to process the big-data to effectively discover the hidden knowledge. A high-speed communication architecture utilizing the Open System Interconnection (OSI) model is designed to transmit the data to a visualization platform. This visualization platform uses Google Earth, a global geographic information system (GIS) to link the geological information with the SG knowledge and visualize the information in user defined fashion. The University of Denver's campus grid is used as a SG test bench and several demonstrations are presented for the proposed platform.

  7. Does interactive animation control improve exploratory data analysis of animated trend visualization?

    Science.gov (United States)

    Abukhodair, Felwa A.; Riecke, Bernhard E.; Erhan, Halil I.; Shaw, Chris D.

    2013-01-01

    OBJECTIVE: Effectively analyzing trends of temporal data becomes a critical task when the amount of data is large. Motion techniques (animation) for scatterplots make it possible to represent lots of data in a single view and make it easy to identify trends and highlight changes. These techniques have recently become very popular and to an extent successful in describing data in presentations. However, compared to static methods of visualization, scatterplot animations may be hard to perceive when the motions are complex. METHODS: This paper studies the effectiveness of interactive scatterplot animation as a visualization technique for data analysis of large data. We compared interactive animations with non-interactive (passive) animations where participants had no control over the animation. Both conditions were evaluated for specific as well as general comprehension of the data. RESULTS: While interactive animation was more effective for specific information analysis, it led to many misunderstandings in the overall comprehension due to the fragmentation of the animation. In general, participants felt that interactivity gave them more confidence and found it more enjoyable and exciting for data exploration. CONCLUSION: Interactive animation of trend visualizations proved to be an effective technique for exploratory data analysis and significantly more accurate than animation alone. With these findings we aim at supporting the use of interactivity to effectively enhance data exploration in animated visualizations.

  8. A randomized controlled trial comparing 2 interventions for visual field loss with standard occupational therapy during inpatient stroke rehabilitation.

    Science.gov (United States)

    Mödden, Claudia; Behrens, Marion; Damke, Iris; Eilers, Norbert; Kastrup, Andreas; Hildebrandt, Helmut

    2012-06-01

    Compensatory and restorative treatments have been developed to improve visual field defects after stroke. However, no controlled trials have compared these interventions with standard occupational therapy (OT). A total of 45 stroke participants with visual field defect admitted for inpatient rehabilitation were randomized to restorative computerized training (RT) using computer-based stimulation of border areas of their visual field defects or to a computer-based compensatory therapy (CT) teaching a visual search strategy. OT, in which different compensation strategies were used to train for activities of daily living, served as standard treatment for the active control group. Each treatment group received 15 single sessions of 30 minutes distributed over 3 weeks. The primary outcome measures were visual field expansion for RT, visual search performance for CT, and reading performance for both treatments. Visual conjunction search, alertness, and the Barthel Index were secondary outcomes. Compared with OT, CT resulted in a better visual search performance, and RT did not result in a larger expansion of the visual field. Intragroup pre-post comparisons demonstrated that CT improved all defined outcome parameters and RT several, whereas OT only improved one. CT improved functional deficits after visual field loss compared with standard OT and may be the intervention of choice during inpatient rehabilitation. A larger trial that includes lesion location in the analysis is recommended.

  9. Effects of visual cues of object density on perception and anticipatory control of dexterous manipulation.

    Directory of Open Access Journals (Sweden)

    Céline Crajé

    Full Text Available Anticipatory force planning during grasping is based on visual cues about the object's physical properties and sensorimotor memories of previous actions with grasped objects. Vision can be used to estimate object mass based on the object size to identify and recall sensorimotor memories of previously manipulated objects. It is not known whether subjects can use density cues to identify the object's center of mass (CM and create compensatory moments in an anticipatory fashion during initial object lifts to prevent tilt. We asked subjects (n = 8 to estimate CM location of visually symmetric objects of uniform densities (plastic or brass, symmetric CM and non-uniform densities (mixture of plastic and brass, asymmetric CM. We then asked whether subjects can use density cues to scale fingertip forces when lifting the visually symmetric objects of uniform and non-uniform densities. Subjects were able to accurately estimate an object's center of mass based on visual density cues. When the mass distribution was uniform, subjects could scale their fingertip forces in an anticipatory fashion based on the estimation. However, despite their ability to explicitly estimate CM location when object density was non-uniform, subjects were unable to scale their fingertip forces to create a compensatory moment and prevent tilt on initial lifts. Hefting object parts in the hand before the experiment did not affect this ability. This suggests a dichotomy between the ability to accurately identify the object's CM location for objects with non-uniform density cues and the ability to utilize this information to correctly scale their fingertip forces. These results are discussed in the context of possible neural mechanisms underlying sensorimotor integration linking visual cues and anticipatory control of grasping.

  10. Effects of visual cues of object density on perception and anticipatory control of dexterous manipulation.

    Science.gov (United States)

    Crajé, Céline; Santello, Marco; Gordon, Andrew M

    2013-01-01

    Anticipatory force planning during grasping is based on visual cues about the object's physical properties and sensorimotor memories of previous actions with grasped objects. Vision can be used to estimate object mass based on the object size to identify and recall sensorimotor memories of previously manipulated objects. It is not known whether subjects can use density cues to identify the object's center of mass (CM) and create compensatory moments in an anticipatory fashion during initial object lifts to prevent tilt. We asked subjects (n = 8) to estimate CM location of visually symmetric objects of uniform densities (plastic or brass, symmetric CM) and non-uniform densities (mixture of plastic and brass, asymmetric CM). We then asked whether subjects can use density cues to scale fingertip forces when lifting the visually symmetric objects of uniform and non-uniform densities. Subjects were able to accurately estimate an object's center of mass based on visual density cues. When the mass distribution was uniform, subjects could scale their fingertip forces in an anticipatory fashion based on the estimation. However, despite their ability to explicitly estimate CM location when object density was non-uniform, subjects were unable to scale their fingertip forces to create a compensatory moment and prevent tilt on initial lifts. Hefting object parts in the hand before the experiment did not affect this ability. This suggests a dichotomy between the ability to accurately identify the object's CM location for objects with non-uniform density cues and the ability to utilize this information to correctly scale their fingertip forces. These results are discussed in the context of possible neural mechanisms underlying sensorimotor integration linking visual cues and anticipatory control of grasping.

  11. How to avoid the `invisible gorilla' in aluminum smelting process control: Visual guidelines

    Science.gov (United States)

    Gao, Yashuang; Taylor, Mark P.; Chen, John J. J.; Hautus, Michael J.

    2011-08-01

    Over the last three decades, process control in aluminum smelters has improved significantly as it is the biggest leverage for cost and energy reduction in production and product quality improvement, as well as for meeting environmental compliance. The implementation of computerized automatic control systems two decades ago was a step change in improvement in the state of the art of process control. However, the complex and dynamic nature of the process requires human monitoring, diagnosis, and intervention from time to time. This study investigates the use of the supervisory screen of the control system of a smelter, as well as the effectiveness of visual guidelines to help the operators to identify process abnormalities. The results show that visual guidelines such as voltage patterns which are used as a reference improve the performance of the operators. Detection time and falsealarm rates were reduced in addition to increasing detection sensitivities. It is proposed that a higher level of human and system interaction would improve the overall performance process control.

  12. Cuttlefish use visual cues to control three-dimensional skin papillae for camouflage.

    Science.gov (United States)

    Allen, Justine J; Mäthger, Lydia M; Barbosa, Alexandra; Hanlon, Roger T

    2009-06-01

    Cephalopods (octopus, squid and cuttlefish) are known for their camouflage. Cuttlefish Sepia officinalis use chromatophores and light reflectors for color change, and papillae to change three-dimensional physical skin texture. Papillae vary in size, shape and coloration; nine distinct sets of papillae are described here. The objective was to determine whether cuttlefish use visual or tactile cues to control papillae expression. Cuttlefish were placed on natural substrates to evoke the three major camouflage body patterns: Uniform/Stipple, Mottle and Disruptive. Three versions of each substrate were presented: the actual substrate, the actual substrate covered with glass (removes tactile information) and a laminated photograph of the substrate (removes tactile and three-dimensional information because depth-of-field information is unavailable). No differences in Small dorsal papillae or Major lateral mantle papillae expression were observed among the three versions of each substrate. Thus, visual (not tactile) cues drive the expression of papillae in S. officinalis. Two sets of papillae (Major lateral mantle papillae and Major lateral eye papillae) showed irregular responses; their control requires future investigation. Finally, more Small dorsal papillae were shown in Uniform/Stipple and Mottle patterns than in Disruptive patterns, which may provide clues regarding the visual mechanisms of background matching versus disruptive coloration.

  13. Soure and Transmission Control for Wireless Visual Sensor Networks with Compressive Sensing and Energy Harvesting

    Directory of Open Access Journals (Sweden)

    Lei You

    2013-05-01

    Full Text Available The lifetime of the emerging Wireless visual sensor network (WVSN is seriously dependent on the energy shored in the battery of its sensor nodes as well as the compression and resource allocation scheme. In this paper, the energy harvesting technology was adopted to provide almost perpetual operation of the WVSN and compressed-sensing-based encoding was used to decrease the power consumption of acquiring visual information at the front-end sensors. A Dynamic Source and Transmission Control Algorithm (DSTCA was proposed to jointly determine source rate, source energy consumption, and the allocation of transmission energy and available bandwidth under energy harvesting and queue stability constraints. A virtual energy queue was introduced to control the resource allocation and the measurement rate in each time slot. The algorithm can guarantee the stability of the visual data queues in all sensors and achieve near-optimal performance. The distributed implementation of the proposed algorithm was discussed and the achievable performance theorem was also given.

  14. Adaptive Network Coded Clouds: High Speed Downloads and Cost-Effective Version Control

    DEFF Research Database (Denmark)

    Sipos, Marton A.; Heide, Janus; Roetter, Daniel Enrique Lucani

    2017-01-01

    developed a novel scheme using recoding with limited packets to trade-off storage space, reliability, and data retrieval speed. Implementation and measurements with commercial cloud providers show that up to 9x less network use is needed compared to other network coding schemes, while maintaining similar...

  15. Stepped care for depression and anxiety in visually impaired older adults: multicentre randomised controlled trial.

    Science.gov (United States)

    van der Aa, Hilde P A; van Rens, Ger H M B; Comijs, Hannie C; Margrain, Tom H; Gallindo-Garre, Francisca; Twisk, Jos W R; van Nispen, Ruth M A

    2015-11-23

    depression and anxiety in visually impaired older adults. This approach could lead to standardised strategies for the screening, monitoring, treatment, and referral of visually impaired older adults with depression and anxiety. Funded by ZonMw InZicht, the Dutch Organisation for Health Research and Development-InSight Society. There are no competing interests. Full dataset and statistical code are available from the corresponding author.Study registration www.trialregister.nl NTR3296. © van der Aa et al 2015.

  16. The impact of visual impairments in self-esteem and locus of control.

    Science.gov (United States)

    Papadopoulos, Konstantinos; Montgomery, Anthony J; Chronopoulou, Elena

    2013-12-01

    This study investigates the differences between adults with visual impairments and sighted adults with regard to locus of control (LOC) and self-esteem. One hundred and eight adults with visual impairments (blindness or low vision) and fifty-five sighted adults took part in this study. Sighted adults showed a higher score on the self-esteem scale than either the individuals with low vision or with blindness. Moreover, analysis indicated no significant differences amongst the three groups of participants regarding LOC. Significant predictors of self-esteem were vision status and age at loss of sight. Significant predictors of LOC were vision status and independent movement. Findings are discussed with regard to their implications for parents, social workers, teachers, and rehabilitation specialists. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Combining Dense Structure From Motion and Visual SLAM in a Behavior-Based Robot Control Architecture

    Directory of Open Access Journals (Sweden)

    Geert De Cubber

    2010-02-01

    Full Text Available In this paper, we present a control architecture for an intelligent outdoor mobile robot. This enables the robot to navigate in a complex, natural outdoor environment, relying on only a single on-board camera as sensory input. This is achieved through a twofold analysis of the visual data stream: a dense structure from motion algorithm calculates a depth map of the environment and a visual simultaneous localization and mapping algorithm builds a map of the surroundings using image features. This information enables a behavior-based robot motion and path planner to navigate the robot through the environment. In this paper, we show the theoretical aspects of setting up this architecture.

  18. Visualization of flow separation and control by vortex generators on an single flap in landing configuration

    Directory of Open Access Journals (Sweden)

    Matějka Milan

    2012-04-01

    Full Text Available This paper focuses on a suppression of the flow separation, which occurs on a deflected flap, by means of vortex generators (VG's. An airfoil NACA 63A421 with a simple flap and vane-type vortex generators were used. The investigation was carried out by using experimental and numerical methods. The data from the numerical simulation of the flapped airfoil without VG's control were used for the vortex generator design. Two sizes, two different shapes and various spacing of the vortex generators were tested. The flow past the airfoil was visualized through three methods, namely tuft filaments technique, oil and thermo camera visualization. The experiments were performed in closed circuit wind tunnels with closed and open test sections. The lift curves for both cases without and with vortex generators were acquired for a lift coefficient improvement determination. The improvement was achieved for several cases by means all of the applied methods.

  19. Visual Servoing Tracking Control of a Ball and Plate System: Design, Implementation and Experimental Validation

    Directory of Open Access Journals (Sweden)

    Ming-Tzu Ho

    2013-07-01

    Full Text Available This paper presents the design, implementation and validation of real‐time visual servoing tracking control for a ball and plate system. The position of the ball is measured with a machine vision system. The image processing algorithms of the machine vision system are pipelined and implemented on a field programmable gate array (FPGA device to meet real‐ time constraints. A detailed dynamic model of the system is derived for the simulation study.By neglecting the high‐order coupling terms, the ball and plate system model is simplified into two decoupled ball and beam systems, and an approximate input‐ output feedback linearization approach is then used to design the controller for trajectory tracking. The designed control law is implemented on a digital signal processor (DSP. The validity of the performance of the developed control system is investigated through simulation and experimental studies. Experimental results show that the designed system functions well with reasonable agreement with simulations.

  20. Effectiveness of basic display augmentation in vehicular control by visual field cues

    Science.gov (United States)

    Grunwald, A. J.; Merhav, S. J.

    1978-01-01

    The paper investigates the effectiveness of different basic display augmentation concepts - fixed reticle, velocity vector, and predicted future vehicle path - for RPVs controlled by a vehicle-mounted TV camera. The task is lateral manual control of a low flying RPV along a straight reference line in the presence of random side gusts. The man-machine system and the visual interface are modeled as a linear time-invariant system. Minimization of a quadratic performance criterion is assumed to underlie the control strategy of a well-trained human operator. The solution for the optimal feedback matrix enables the explicit computation of the variances of lateral deviation and directional error of the vehicle and of the control force that are used as performance measures.

  1. Visual Servoing Tracking Control of a Ball and Plate System: Design, Implementation and Experimental Validation

    Directory of Open Access Journals (Sweden)

    Ming-Tzu Ho

    2013-07-01

    Full Text Available This paper presents the design, implementation and validation of real-time visual servoing tracking control for a ball and plate system. The position of the ball is measured with a machine vision system. The image processing algorithms of the machine vision system are pipelined and implemented on a field programmable gate array (FPGA device to meet real-time constraints. A detailed dynamic model of the system is derived for the simulation study. By neglecting the high-order coupling terms, the ball and plate system model is simplified into two decoupled ball and beam systems, and an approximate input-output feedback linearization approach is then used to design the controller for trajectory tracking. The designed control law is implemented on a digital signal processor (DSP. The validity of the performance of the developed control system is investigated through simulation and experimental studies. Experimental results show that the designed system functions well with reasonable agreement with simulations.

  2. Dyslexic children suffer from less informative visual cues to control posture.

    Science.gov (United States)

    Razuk, Milena; Barela, Jose A

    2014-09-01

    The goal of this study was to investigate the effects of manipulation of the characteristics of visual stimulus on postural control in dyslexic children. A total of 18 dyslexic and 18 non-dyslexic children stood upright inside a moving room, as still as possible, and looked at a target at different conditions of distance between the participant and a moving room frontal wall (25-150 cm) and vision (full and central). The first trial was performed without vision (baseline). Then four trials were performed in which the room remained stationary and eight trials with the room moving, lasting 60s each. Mean sway amplitude, coherence, relative phase, and angular deviation were calculated. The results revealed that dyslexic children swayed with larger magnitude in both stationary and moving conditions. When the room remained stationary, all children showed larger body sway magnitude at 150 cm distance. Dyslexic children showed larger body sway magnitude in central compared to full vision condition. In the moving condition, body sway magnitude was similar between dyslexic and non-dyslexic children but the coupling between visual information and body sway was weaker in dyslexic children. Moreover, in the absence of peripheral visual cues, induced body sway in dyslexic children was temporally delayed regarding visual stimulus. Taken together, these results indicate that poor postural control performance in dyslexic children is related to how sensory information is acquired from the environment and used to produce postural responses. In conditions in which sensory cues are less informative, dyslexic children take longer to process sensory stimuli in order to obtain precise information, which leads to performance deterioration.

  3. Integration of bio-inspired, control-based visual and olfactory data for the detection of an elusive target

    Science.gov (United States)

    Duong, Tuan A.; Duong, Nghi; Le, Duong

    2017-01-01

    In this paper, we present an integration technique using a bio-inspired, control-based visual and olfactory receptor system to search for elusive targets in practical environments where the targets cannot be seen obviously by either sensory data. Bio-inspired Visual System is based on a modeling of extended visual pathway which consists of saccadic eye movements and visual pathway (vertebrate retina, lateral geniculate nucleus and visual cortex) to enable powerful target detections of noisy, partial, incomplete visual data. Olfactory receptor algorithm, namely spatial invariant independent component analysis, that was developed based on data of old factory receptor-electronic nose (enose) of Caltech, is adopted to enable the odorant target detection in an unknown environment. The integration of two systems is a vital approach and sets up a cornerstone for effective and low-cost of miniaturized UAVs or fly robots for future DOD and NASA missions, as well as for security systems in Internet of Things environments.

  4. Executive control of stimulus-driven and goal-directed attention in visual working memory.

    Science.gov (United States)

    Hu, Yanmei; Allen, Richard J; Baddeley, Alan D; Hitch, Graham J

    2016-10-01

    We examined the role of executive control in stimulus-driven and goal-directed attention in visual working memory using probed recall of a series of objects, a task that allows study of the dynamics of storage through analysis of serial position data. Experiment 1 examined whether executive control underlies goal-directed prioritization of certain items within the sequence. Instructing participants to prioritize either the first or final item resulted in improved recall for these items, and an increase in concurrent task difficulty reduced or abolished these gains, consistent with their dependence on executive control. Experiment 2 examined whether executive control is also involved in the disruption caused by a post-series visual distractor (suffix). A demanding concurrent task disrupted memory for all items except the most recent, whereas a suffix disrupted only the most recent items. There was no interaction when concurrent load and suffix were combined, suggesting that deploying selective attention to ignore the distractor did not draw upon executive resources. A final experiment replicated the independent interfering effects of suffix and concurrent load while ruling out possible artifacts. We discuss the results in terms of a domain-general episodic buffer in which information is retained in a transient, limited capacity privileged state, influenced by both stimulus-driven and goal-directed processes. The privileged state contains the most recent environmental input together with goal-relevant representations being actively maintained using executive resources.

  5. Application of the control method by visual path to the water injection projects of Petroleos Mexicanos

    Energy Technology Data Exchange (ETDEWEB)

    Pechir, Q.V.M.

    1972-04-01

    In the present work, the importance is pointed out of the physical and economical magnitude of secondary recovery of oil by injection of water. This is for the purpose of emphasizing the urgent necessity of attending to the problems of control and supervision which present themselves during the development of the projects. An example of such a project is cited (Tamaulipas-Constitucion) where the problems and failures gave many opportunities for delay in completion of some of the work. In some instances, there was overspending which might have been avoided in great part, if there had been controls and supervision suitable and adequate in importance to the magnitude and complexity of the project. Because of such situations, and for overcoming the initial deficiencies in control and supervision of these water-injection projects, it was decided to adopt the Visiflex method of control and the Visual Path method of work scheduling. A description of the parts is integrated into the method as well as the techniques of its application n the mentioned project, including a model of the Visual Path Program for the water- injection project in the Caliza San Andres (San Andres Limestone) formations of the Tamaulipas-Constitucion oil field.

  6. ERROR-CONTROL CODING OF ADS-B MESSAGES FOR IRIDIUM SATELLITES

    Directory of Open Access Journals (Sweden)

    Volodymyr Kharchenko

    2013-12-01

    Full Text Available For modelling of ADS-B messages transmitting on the base of low-orbit satellite constellation Іrіdіum the model of a communication channel “Aircraft - Satellite - Ground Station” was built using MATLAB Sіmulіnk. This model allowed to investigate dependences of the Bit Error Rate on a type of  signal coding/decoding, ratio Eb/N0 and satellite repeater gain

  7. Patient-Physician Communication About Code Status Preferences: A Randomized Controlled Trial

    Science.gov (United States)

    Rhondali, Wadih; Perez-Cruz, Pedro; Hui, David; Chisholm, Gary B.; Dalal, Shalini; Baile, Walter; Chittenden, Eva; Bruera, Eduardo

    2013-01-01

    Purpose Code status discussions are important in cancer care. The best modality for such discussions has not been established. Our objective was to determine the impact of a physician ending a code status discussion with a question (autonomy approach) versus a recommendation (beneficence approach) on patients' do-not-resuscitate (DNR) preference. Methods Patients in a supportive care clinic watched two videos showing a physician-patient discussion regarding code status. Both videos were identical except for the ending: one ended with the physician asking for the patient's code status preference and the other with the physician recommending DNR. Patients were randomly assigned to watch the videos in different sequences. The main outcome was the proportion of patients choosing DNR for the video patient. Results 78 patients completed the study. 74% chose DNR after the question video, 73% after the recommendation video. Median physician compassion score was very high and not different for both videos. 30/30 patients who had chosen DNR for themselves and 30/48 patients who had not chosen DNR for themselves chose DNR for the video patient (100% v/s 62%). Age (OR=1.1/year) and white ethnicity (OR=9.43) predicted DNR choice for the video patient. Conclusion Ending DNR discussions with a question or a recommendation did not impact DNR choice or perception of physician compassion. Therefore, both approaches are clinically appropriate. All patients who chose DNR for themselves and most patients who did not choose DNR for themselves chose DNR for the video patient. Age and race predicted DNR choice. PMID:23564395

  8. New neurons in aging brains: molecular control by small non-coding RNAs

    Directory of Open Access Journals (Sweden)

    Marijn eSchouten

    2012-02-01

    Full Text Available Adult neurogenesis is a process that continues in the adult and also aging brain. It generates functional neurons from neural stem cells present in specific brain regions. This phenomenon is largely confined to two main regions: the subventricular zone of the lateral ventricle, and the subgranular zone of the dentate gyrus, in the hippocampus. With age, the hippocampus and particularly the dentate gyrus are affected. For instance, adult neurogenesis is decreased with aging, in both the number of proliferating cells as well as their neuronal differentiation, while in parallel an age-associated decline in cognitive performance is often seen. Surprisingly, the synaptogenic potential of adult-born neurons appears unaffected by aging. Therefore, although proliferation, differentiation, survival and synaptogenesis of adult-born new neurons in the dentate gyrus are closely related to each other, they appear differentially regulated with aging. In this review we discuss the crucial role of a novel class of recently discovered regulators of gene expression, i.e. the small non-coding RNAs, in the development of adult neurogenesis from neural stem cells to functionally integrated neurons. In particular, a subgroup of the small non-coding RNAs, the microRNAs, fine-tune many events during adult neurogenesis progression. Moreover, multiple small non-coding RNAs are differentially expressed in the aged hippocampus. This makes small non-coding RNAs appealing candidates to orchestrate, and possibly correct or prevent, the functional alterations in adult neurogenesis and cognition associated with aging. Finally, we briefly summarize observations that link changes in circulating levels of steroid hormones with alterations in adult neurogenesis and subsequent vulnerability to psychopathology in advanced age, and discuss a possible role of microRNAs in stress-associated alterations in adult neurogenesis during aging.

  9. Context-dependent coding and gain control in the auditory system of crickets.

    Science.gov (United States)

    Clemens, Jan; Rau, Florian; Hennig, R Matthias; Hildebrandt, K Jannis

    2015-10-01

    Sensory systems process stimuli that greatly vary in intensity and complexity. To maintain efficient information transmission, neural systems need to adjust their properties to these different sensory contexts, yielding adaptive or stimulus-dependent codes. Here, we demonstrated adaptive spectrotemporal tuning in a small neural network, i.e. the peripheral auditory system of the cricket. We found that tuning of cricket auditory neurons was sharper for complex multi-band than for simple single-band stimuli. Information theoretical considerations revealed that this sharpening improved information transmission by separating the neural representations of individual stimulus components. A network model inspired by the structure of the cricket auditory system suggested two putative mechanisms underlying this adaptive tuning: a saturating peripheral nonlinearity could change the spectral tuning, whereas broad feed-forward inhibition was able to reproduce the observed adaptive sharpening of temporal tuning. Our study revealed a surprisingly dynamic code usually found in more complex nervous systems and suggested that stimulus-dependent codes could be implemented using common neural computations.

  10. Quality control of the treatment planning systems dose calculations in external radiation therapy using the Penelope Monte Carlo code; Controle qualite des systemes de planification dosimetrique des traitements en radiotherapie externe au moyen du code Monte-Carlo Penelope

    Energy Technology Data Exchange (ETDEWEB)

    Blazy-Aubignac, L

    2007-09-15

    The treatment planning systems (T.P.S.) occupy a key position in the radiotherapy service: they realize the projected calculation of the dose distribution and the treatment duration. Traditionally, the quality control of the calculated distribution doses relies on their comparisons with dose distributions measured under the device of treatment. This thesis proposes to substitute these dosimetry measures to the profile of reference dosimetry calculations got by the Penelope Monte-Carlo code. The Monte-Carlo simulations give a broad choice of test configurations and allow to envisage a quality control of dosimetry aspects of T.P.S. without monopolizing the treatment devices. This quality control, based on the Monte-Carlo simulations has been tested on a clinical T.P.S. and has allowed to simplify the quality procedures of the T.P.S.. This quality control, in depth, more precise and simpler to implement could be generalized to every center of radiotherapy. (N.C.)

  11. Volitional regulation of emotions produces distributed alterations in connectivity between visual, attention control, and default networks.

    Science.gov (United States)

    Sripada, Chandra; Angstadt, Michael; Kessler, Daniel; Phan, K Luan; Liberzon, Israel; Evans, Gary W; Welsh, Robert C; Kim, Pilyoung; Swain, James E

    2014-04-01

    The ability to volitionally regulate emotions is critical to health and well-being. While patterns of neural activation during emotion regulation have been well characterized, patterns of connectivity between regions remain less explored. It is increasingly recognized that the human brain is organized into large-scale intrinsic connectivity networks (ICNs) whose interrelationships are altered in characteristic ways during psychological tasks. In this fMRI study of 54 healthy individuals, we investigated alterations in connectivity within and between ICNs produced by the emotion regulation strategy of reappraisal. In order to gain a comprehensive picture of connectivity changes, we utilized connectomic psychophysiological interactions (PPI), a whole-brain generalization of standard single-seed PPI methods. In particular, we quantified PPI connectivity pair-wise across 837 ROIs placed throughout the cortex. We found that compared to maintaining one's emotional responses, engaging in reappraisal produced robust and distributed alterations in functional connections involving visual, dorsal attention, frontoparietal, and default networks. Visual network in particular increased connectivity with multiple ICNs including dorsal attention and default networks. We interpret these findings in terms of the role of these networks in mediating critical constituent processes in emotion regulation, including visual processing, stimulus salience, attention control, and interpretation and contextualization of stimuli. Our results add a new network perspective to our understanding of the neural underpinnings of emotion regulation, and highlight that connectomic methods can play a valuable role in comprehensively investigating modulation of connectivity across task conditions.

  12. A Randomized Control Trial Exploring the Effect of Mental Rehearsal and Cognitive Visualization on Microsurgery Skills.

    Science.gov (United States)

    Chadha, Priyanka; Hachach-Haram, Nadine; Shurey, Sandra; Mohanna, Pari-Naz

    2016-09-01

    Background Many factors are known to influence the performance of surgeons within the operating theater, including tiredness, previous experience, and stress levels. The effects of mental rehearsal and cognitive visualization on microsurgical skills have not been assessed. Methods Thirty-six subjects recruited from the Northwick Park Microsurgery Skills Course were randomized into three groups; (1) a control group (C) with no mental rehearsal script, (2) a visual anastomosis group (VA), with a detailed rat anastomosis script, and (3) a visual relaxation (VR) group with a relaxation script, unrelated to the anastomosis. Participants ran through relevant scripts from day 2 to 5 and were assessed through recorded arterial rat anastomosis, scored using the structured assessment of microsurgery skills. Results Results were analyzed by double-blinded assessors. No statistical significance was found on Monday and Tuesday (first day post intervention), p = 0.326 (VA vs. C) and p = 0.283 (VR vs. C). A statistically significant difference was noted at the end of day 4; p rehearsal in microsurgery may result in fewer complications from errors and thus lead to enhanced patient safety and better operative outcomes.

  13. Phase-dependent visual control of the zigzag paths of navigating wood ants.

    Science.gov (United States)

    Lent, David D; Graham, Paul; Collett, Thomas S

    2013-12-02

    Animals sometimes take sinuous paths to a goal. Insects, tracking an odor trail on the ground [1-3] or moving up an odor plume in the air [4, 5], generally follow zigzag paths. Some insects [6-8] take a zigzag approach to visual targets, perhaps to obtain parallax information. How does an animal keep its overall path in the direction of the goal without disrupting a zigzag pattern? We describe here the wood ant's strategy when guided by a familiar visual scene. If their travel direction is correct, ants face the goal briefly after each turning point along their zigzag path. If the direction is wrong, they turn rapidly at this point to place the scene correctly on their retina. Such saccade-like turns are rare elsewhere in the zigzag. Similarly, when the scene is made to jump to a new position on their retina, ants wait until an expected goal-facing phase of the zigzag before turning to correct the imposed error. Correctly timed, intermittent control allows an animal to adjust its path without compromising additional roles for the zigzag pattern in gathering visual information or in using odor cues for guidance. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. 3D Data Mapping and Real-Time Experiment Control and Visualization in Brain Slices.

    Science.gov (United States)

    Navarro, Marco A; Hibbard, Jaime V K; Miller, Michael E; Nivin, Tyler W; Milescu, Lorin S

    2015-10-20

    Here, we propose two basic concepts that can streamline electrophysiology and imaging experiments in brain slices and enhance data collection and analysis. The first idea is to interface the experiment with a software environment that provides a 3D scene viewer in which the experimental rig, the brain slice, and the recorded data are represented to scale. Within the 3D scene viewer, the user can visualize a live image of the sample and 3D renderings of the recording electrodes with real-time position feedback. Furthermore, the user can control the instruments and visualize their status in real time. The second idea is to integrate multiple types of experimental data into a spatial and temporal map of the brain slice. These data may include low-magnification maps of the entire brain slice, for spatial context, or any other type of high-resolution structural and functional image, together with time-resolved electrical and optical signals. The entire data collection can be visualized within the 3D scene viewer. These concepts can be applied to any other type of experiment in which high-resolution data are recorded within a larger sample at different spatial and temporal coordinates.

  15. Development of the simulation platform between EAST plasma control system and the tokamak simulation code based on Simulink

    Science.gov (United States)

    Sen, WANG; Qiping, YUAN; Bingjia, XIAO

    2017-03-01

    Plasma control system (PCS), mainly developed for real-time feedback control calculation, plays a significant part during normal discharges in a magnetic fusion device, while the tokamak simulation code (TSC) is a nonlinear numerical model that studies the time evolution of an axisymmetric magnetized tokamak plasma. The motivation to combine these two codes for an integrated simulation is specified by the facts that the control system module in TSC is relatively simple compared to PCS, and meanwhile, newly-implemented control algorithms in PCS, before applied to experimental validations, require numerical validations against a tokamak plasma simulator that TSC can act as. In this paper, details of establishment of the integrated simulation framework between the EAST PCS and TSC are generically presented, and the poloidal power supply model and data acquisition model that have been implemented in this framework are described as well. In addition, the correctness of data interactions among the EAST PCS, Simulink and TSC is clearly confirmed during an interface test, and in a simulation test, the RZIP control scheme in the EAST PCS is numerically validated using this simulation platform. Supported by the National Magnetic Confinement Fusion Science Program of China (No. 2014GB103000) and the National Natural Science Foundation of China (No. 11205200).

  16. Visual and proprioceptive contributions to postural control of upright stance in unilateral vestibulopathy.

    Science.gov (United States)

    Eysel-Gosepath, Katrin; McCrum, Christopher; Epro, Gaspar; Brüggemann, Gert-Peter; Karamanidis, Kiros

    2016-06-01

    Preserving upright stance requires central integration of the sensory systems and appropriate motor output from the neuromuscular system to keep the centre of pressure (COP) within the base of support. Unilateral peripheral vestibular disorder (UPVD) causes diminished stance stability. The aim of this study was to determine the limits of stability and to examine the contribution of multiple sensory systems to upright standing in UPVD patients and healthy subjects. We hypothesized that closure of the eyes and Achilles tendon vibration during upright stance will augment the postural sway in UPVD patients more than in healthy subjects. Seventeen UPVD patients and 17 healthy subjects performed six tasks on a force plate: forwards and backwards leaning, to determine limits of stability, and upright standing with and without Achilles tendon vibration, each with eyes open and closed (with blackout glasses). The COP displacement of the patients was significantly greater in the vibration tasks than the controls and came closer to the posterior base of support boundary than the controls in all tasks. Achilles tendon vibration led to a distinctly more backward sway in both subject groups. Five of the patients could not complete the eyes closed with vibration task. Due to the greater reduction in stance stability when the proprioceptive, compared with the visual, sensory system was disturbed, we suggest that proprioception may be more important for maintaining upright stance than vision. UPVD patients, in particular, showed more difficulty in controlling postural stability in the posterior direction with visual and proprioceptive sensory disturbance.

  17. Postural control of ballet dancers: a specific use of visual input for artistic purposes.

    Science.gov (United States)

    Hugel, F; Cadopi, M; Kohler, F; Perrin, P

    1999-02-01

    Dance is a specific expression of human motor behaviour. This artistic physical activity depends upon an effective technical training with important postural components and necessitates the codification of sensory inputs to build mental representations of the action to be produced. Proprioception and vision being two fundamental sensory modalities in classical ballet, this study attempted to determine the importance of the visual input for postural control during the practice of this activity. First, this work compared the performances of 18 professional ballet dancers and 46 non-dancers on a platform of forces during static posturographic tests in open or closed eyes situation. Then, we studied how professional dancers achieve balance in postures specific of classical ballet: on demi-pointe and on pointe. The results indicate that visual inputs are important in classical ballet since dancers only performed better than controls in eyes open conditions. The similar results obtained on pointe with eyes open or closed conversely suggest that training in classical ballet develops specific modalities of balance which are not transferable to posture control in daily life situations.

  18. Projection on Proper elements for code control: Verification, numerical convergence, and reduced models. Application to plasma turbulence simulations

    Science.gov (United States)

    Cartier-Michaud, T.; Ghendrih, P.; Sarazin, Y.; Abiteboul, J.; Bufferand, H.; Dif-Pradalier, G.; Garbet, X.; Grandgirard, V.; Latu, G.; Norscini, C.; Passeron, C.; Tamain, P.

    2016-02-01

    The Projection on Proper elements (PoPe) is a novel method of code control dedicated to (1) checking the correct implementation of models, (2) determining the convergence of numerical methods, and (3) characterizing the residual errors of any given solution at very low cost. The basic idea is to establish a bijection between a simulation and a set of equations that generate it. Recovering equations is direct and relies on a statistical measure of the weight of the various operators. This method can be used in any number of dimensions and any regime, including chaotic ones. This method also provides a procedure to design reduced models and quantify its ratio of cost to benefit. PoPe is applied to a kinetic and a fluid code of plasma turbulence.

  19. The effects of Tai Chi on the balance control of elderly persons with visual impairment: a randomised clinical trial.

    Science.gov (United States)

    Chen, Ellen W; Fu, Amy S N; Chan, K M; Tsang, William W N

    2012-03-01

    balance control is a major problem for older individuals with poor vision. There are limitations, however, for visually impaired elderly persons wishing to participate in exercise programmes. The benefits of Tai Chi for balance control, muscle strength and preventing falls have been demonstrated with sighted elderly subjects. This study was designed to extend those findings to elderly persons with visual impairment. to investigate the effects of Tai Chi on the balance control of elderly persons with visual impairment. randomised clinical trial. residential care homes. forty visually impaired persons aged 70 or over. the participants were randomly divided into Tai Chi and control groups and assessed pre- and post-intervention using three tests: (i) passive knee joint repositioning to test knee proprioception; (ii) concentric isokinetic strength of the knee extensors and flexors and (iii) a sensory organisation test to quantify an individual's ability to maintain balance in a variety of complex sensory conditions. after intervention, the Tai Chi participants showed significant improvements in knee proprioception and in their visual and vestibular ratios compared with the control group. practicing Tai Chi can improve the balance control of visually impaired elderly persons.

  20. International codes and agreements to restrict the promotion of harmful products can hold lessons for the control of alcohol marketing.

    Science.gov (United States)

    Landon, Jane; Lobstein, Tim; Godfrey, Fiona; Johns, Paula; Brookes, Chris; Jernigan, David

    2017-01-01

    Background and aims The 2011 UN Summit on Non-Communicable Disease failed to call for global action on alcohol marketing despite calls in the World Health Organization (WHO) Global Action Plan on Non-Communicable Diseases 2013-20 to restrict or ban alcohol advertising. In this paper we ask what it might take to match the global approach to tobacco enshrined in the Framework Convention on Tobacco Control (FCTC), and suggest that public health advocates can learn from the development of the FCTC and the Code of Marketing on infant formula milks and the recent recommendations on restricting food marketing to children. Methods Narrative review of qualitative accounts of the processes that created and monitor existing codes and treaties to restrict the marketing of consumer products, specifically breast milk substitutes, unhealthy foods and tobacco. Findings The development of treaties and codes for market restrictions include: (i) evidence of a public health crisis; (ii) the cost of inaction; (iii) civil society advocacy; (iv) the building of capacity; (v) the management of conflicting interests in policy development; and (vi) the need to consider monitoring and accountability to ensure compliance. Conclusion International public health treaties and codes provide an umbrella under which national governments can strengthen their own legislation, assisted by technical support from international agencies and non-governmental organizations. Three examples of international agreements, those for breast milk substitutes, unhealthy foods and tobacco, can provide lessons for the public health community to make progress on alcohol controls. Lessons include stronger alliances of advocates and health professionals and better tools and capacity to monitor and report current marketing practices and trends. © 2016 Society for the Study of Addiction.

  1. Visual control of wheeled mobile robots unifying vision and control in generic approaches

    CERN Document Server

    Becerra, Héctor M

    2014-01-01

    Vision-based control of wheeled mobile robots is an interesting field of research from a scientific and even social point of view due to its potential applicability. This book presents a formal treatment of some aspects of control theory applied to the problem of vision-based pose regulation of wheeled mobile robots. In this problem, the robot has to reach a desired position and orientation, which are specified by a target image. It is faced in such a way that vision and control are unified to achieve stability of the closed loop, a large region of convergence, without local minima, and good robustness against parametric uncertainty. Three different control schemes that rely on monocular vision as unique sensor are presented and evaluated experimentally. A common benefit of these approaches is that they are valid for imaging systems obeying approximately a central projection model, e.g., conventional cameras, catadioptric systems and some fisheye cameras. Thus, the presented control schemes are generic approa...

  2. Self-Control and Impulsiveness in Nondieting Adult Human Females: Effects of Visual Food Cues and Food Deprivation

    Science.gov (United States)

    Forzano, Lori-Ann B.; Chelonis, John J.; Casey, Caitlin; Forward, Marion; Stachowiak, Jacqueline A.; Wood, Jennifer

    2010-01-01

    Self-control can be defined as the choice of a larger, more delayed reinforcer over a smaller, less delayed reinforcer, and impulsiveness as the opposite. Previous research suggests that exposure to visual food cues affects adult humans' self-control. Previous research also suggests that food deprivation decreases adult humans' self-control. The…

  3. Self-Control and Impulsiveness in Nondieting Adult Human Females: Effects of Visual Food Cues and Food Deprivation

    Science.gov (United States)

    Forzano, Lori-Ann B.; Chelonis, John J.; Casey, Caitlin; Forward, Marion; Stachowiak, Jacqueline A.; Wood, Jennifer

    2010-01-01

    Self-control can be defined as the choice of a larger, more delayed reinforcer over a smaller, less delayed reinforcer, and impulsiveness as the opposite. Previous research suggests that exposure to visual food cues affects adult humans' self-control. Previous research also suggests that food deprivation decreases adult humans' self-control. The…

  4. Visual analytics of geo-social interaction patterns for epidemic control.

    Science.gov (United States)

    Luo, Wei

    2016-08-10

    Human interaction and population mobility determine the spatio-temporal course of the spread of an airborne disease. This research views such spreads as geo-social interaction problems, because population mobility connects different groups of people over geographical locations via which the viruses transmit. Previous research argued that geo-social interaction patterns identified from population movement data can provide great potential in designing effective pandemic mitigation. However, little work has been done to examine the effectiveness of designing control strategies taking into account geo-social interaction patterns. To address this gap, this research proposes a new framework for effective disease control; specifically this framework proposes that disease control strategies should start from identifying geo-social interaction patterns, designing effective control measures accordingly, and evaluating the efficacy of different control measures. This framework is used to structure design of a new visual analytic tool that consists of three components: a reorderable matrix for geo-social mixing patterns, agent-based epidemic models, and combined visualization methods. With real world human interaction data in a French primary school as a proof of concept, this research compares the efficacy of vaccination strategies between the spatial-social interaction patterns and the whole areas. The simulation results show that locally targeted vaccination has the potential to keep infection to a small number and prevent spread to other regions. At some small probability, the local control strategies will fail; in these cases other control strategies will be needed. This research further explores the impact of varying spatial-social scales on the success of local vaccination strategies. The results show that a proper spatial-social scale can help achieve the best control efficacy with a limited number of vaccines. The case study shows how GS-EpiViz does support the design

  5. Experiences using IAEA Code of practice for radiation sterilization of tissue allografts: Validation and routine control

    Energy Technology Data Exchange (ETDEWEB)

    Hilmy, N. [Batan Research Tissue Bank (BRTB), Centre for Research and Development of Isotopes and Radiation Technology, P.O. Box 7002, JKSKL, Jakarta 12070 (Indonesia)], E-mail: nazly@batan.go.id; Febrida, A.; Basril, A. [Batan Research Tissue Bank (BRTB), Centre for Research and Development of Isotopes and Radiation Technology, P.O. Box 7002, JKSKL, Jakarta 12070 (Indonesia)

    2007-11-15

    Problems of tissue allografts in using International Standard (ISO) 11137 for validation of radiation sterilization dose (RSD) are limited and low numbers of uniform samples per production batch, those are products obtained from one donor. Allograft is a graft transplanted between two different individuals of the same species. The minimum number of uniform samples needed for verification dose (VD) experiment at the selected sterility assurance level (SAL) per production batch according to the IAEA Code is 20, i.e., 10 for bio-burden determination and the remaining 10 for sterilization test. Three methods of the IAEA Code have been used for validation of RSD, i.e., method A1 that is a modification of method 1 of ISO 11137:1995, method B (ISO 13409:1996), and method C (AAMI TIR 27:2001). This paper describes VD experiments using uniform products obtained from one cadaver donor, i.e., cancellous bones, demineralized bone powders and amnion grafts from one life donor. Results of the verification dose experiments show that RSD is 15.4 kGy for cancellous and demineralized bone grafts and 19.2 kGy for amnion grafts according to method A1 and 25 kGy according to methods B and C.

  6. A lower limb exoskeleton control system based on steady state visual evoked potentials

    Science.gov (United States)

    Kwak, No-Sang; Müller, Klaus-Robert; Lee, Seong-Whan

    2015-10-01

    Objective. We have developed an asynchronous brain-machine interface (BMI)-based lower limb exoskeleton control system based on steady-state visual evoked potentials (SSVEPs). Approach. By decoding electroencephalography signals in real-time, users are able to walk forward, turn right, turn left, sit, and stand while wearing the exoskeleton. SSVEP stimulation is implemented with a visual stimulation unit, consisting of five light emitting diodes fixed to the exoskeleton. A canonical correlation analysis (CCA) method for the extraction of frequency information associated with the SSVEP was used in combination with k-nearest neighbors. Main results. Overall, 11 healthy subjects participated in the experiment to evaluate performance. To achieve the best classification, CCA was first calibrated in an offline experiment. In the subsequent online experiment, our results exhibit accuracies of 91.3 ± 5.73%, a response time of 3.28 ± 1.82 s, an information transfer rate of 32.9 ± 9.13 bits/min, and a completion time of 1100 ± 154.92 s for the experimental parcour studied. Significance. The ability to achieve such high quality BMI control indicates that an SSVEP-based lower limb exoskeleton for gait assistance is becoming feasible.

  7. Visual Trajectory-Tracking Model-Based Control for Mobile Robots

    Directory of Open Access Journals (Sweden)

    Andrej Zdešar

    2013-09-01

    Full Text Available In this paper we present a visual-control algorithm for driving a mobile robot along the reference trajectory. The configuration of the system consists of a two-wheeled differentially driven mobile robot that is observed by an overhead camera, which can be placed at arbitrary, but reasonable, inclination with respect to the ground plane. The controller must be capable of generating appropriate tangential and angular control velocities for the trajectory-tracking problem, based on the information received about the robot position obtained in the image. To be able to track the position of the robot through a sequence of images in real-time, the robot is marked with an artificial marker that can be distinguishably recognized by the image recognition subsystem. Using the property of differential flatness, a dynamic feedback compensator can be designed for the system, thereby extending the system into a linear form. The presented control algorithm for reference tracking combines a feedforward and a feedback loop, the structure also known as a two DOF control scheme. The feedforward part should drive the system to the vicinity of the reference trajectory and the feedback part should eliminate any errors that occur due to noise and other disturbances etc. The feedforward control can never achieve accurate reference following, but this deficiency can be eliminated with the introduction of the feedback loop. The design of the model predictive control is based on the linear error model. The model predictive control is given in analytical form, so the computational burden is kept at a reasonable level for real-time implementation. The control algorithm requires that a reference trajectory is at least twice differentiable function. A suitable approach to design such a trajectory is by exploiting some useful properties of the Bernstein-Bézier parametric curves. The simulation experiments as well as real system experiments on a robot normally used in the

  8. Formation of visual memories controlled by gamma power phase-locked to alpha oscillations

    Science.gov (United States)

    Park, Hyojin; Lee, Dong Soo; Kang, Eunjoo; Kang, Hyejin; Hahm, Jarang; Kim, June Sic; Chung, Chun Kee; Jiang, Haiteng; Gross, Joachim; Jensen, Ole

    2016-06-01

    Neuronal oscillations provide a window for understanding the brain dynamics that organize the flow of information from sensory to memory areas. While it has been suggested that gamma power reflects feedforward processing and alpha oscillations feedback control, it remains unknown how these oscillations dynamically interact. Magnetoencephalography (MEG) data was acquired from healthy subjects who were cued to either remember or not remember presented pictures. Our analysis revealed that in anticipation of a picture to be remembered, alpha power decreased while the cross-frequency coupling between gamma power and alpha phase increased. A measure of directionality between alpha phase and gamma power predicted individual ability to encode memory: stronger control of alpha phase over gamma power was associated with better memory. These findings demonstrate that encoding of visual information is reflected by a state determined by the interaction between alpha and gamma activity.

  9. Virtual- and real-world operation of mobile robotic manipulators: integrated simulation, visualization, and control environment

    Science.gov (United States)

    Chen, ChuXin; Trivedi, Mohan M.

    1992-03-01

    This research is focused on enhancing the overall productivity of an integrated human-robot system. A simulation, animation, visualization, and interactive control (SAVIC) environment has been developed for the design and operation of an integrated robotic manipulator system. This unique system possesses the abilities for multisensor simulation, kinematics and locomotion animation, dynamic motion and manipulation animation, transformation between real and virtual modes within the same graphics system, ease in exchanging software modules and hardware devices between real and virtual world operations, and interfacing with a real robotic system. This paper describes a working system and illustrates the concepts by presenting the simulation, animation, and control methodologies for a unique mobile robot with articulated tracks, a manipulator, and sensory modules.

  10. Visual Attention Allocation Between Robotic Arm and Environmental Process Control: Validating the STOM Task Switching Model

    Science.gov (United States)

    Wickens, Christopher; Vieanne, Alex; Clegg, Benjamin; Sebok, Angelia; Janes, Jessica

    2015-01-01

    Fifty six participants time shared a spacecraft environmental control system task with a realistic space robotic arm control task in either a manual or highly automated version. The former could suffer minor failures, whose diagnosis and repair were supported by a decision aid. At the end of the experiment this decision aid unexpectedly failed. We measured visual attention allocation and switching between the two tasks, in each of the eight conditions formed by manual-automated arm X expected-unexpected failure X monitoring- failure management. We also used our multi-attribute task switching model, based on task attributes of priority interest, difficulty and salience that were self-rated by participants, to predict allocation. An un-weighted model based on attributes of difficulty, interest and salience accounted for 96 percent of the task allocation variance across the 8 different conditions. Task difficulty served as an attractor, with more difficult tasks increasing the tendency to stay on task.

  11. A Novel Architecture for Adaptive Traffic Control in Network on Chip using Code Division Multiple Access Technique

    Directory of Open Access Journals (Sweden)

    Fatemeh. Dehghani

    2016-08-01

    Full Text Available Network on chip has emerged as a long-term and effective method in Multiprocessor System-on-Chip communications in order to overcome the bottleneck in bus based communication architectures. Efficiency and performance of network on chip is so dependent on the architecture and structure of the network. In this paper a new structure and architecture for adaptive traffic control in network on chip using Code Division Multiple Access technique is presented. To solve the problem of synchronous access to bus based interconnection the code division multiple access technique was applied. In the presented structure that is based upon mesh topology and simple routing method we attempted to increase the exchanged data bandwidth rate among different cores. Also an attempt has been made to increase the performance by isolating the target address transfer path from data transfer path. The main goal of this paper is presenting a new structure to improve energy consumption, area and maximum frequency in network on chip systems using information coding and decoding techniques. The presented structure is simulated using Xilinx ISE software and the results show effectiveness of this architecture.

  12. SCALE: A modular code system for performing standardized computer analyses for licensing evaluation. Control modules -- Volume 1, Revision 4

    Energy Technology Data Exchange (ETDEWEB)

    Landers, N.F.; Petrie, L.M.; Knight, J.R. [Oak Ridge National Lab., TN (United States)] [and others

    1995-04-01

    SCALE--a modular code system for Standardized Computer Analyses Licensing Evaluation--has been developed by Oak Ridge National Laboratory at the request of the US Nuclear Regulatory Commission. The SCALE system utilizes well-established computer codes and methods within standard analysis sequences that (1) allow an input format designed for the occasional user and/or novice, (2) automate the data processing and coupling between modules, and (3) provide accurate and reliable results. System development has been directed at problem-dependent cross-section processing and analysis of criticality safety, shielding, heat transfer, and depletion/decay problems. Since the initial release of SCALE in 1980, the code system has been heavily used for evaluation of nuclear fuel facility and package designs. This revision documents Version 4.2 of the system. This manual is divided into three volumes: Volume 1--for the control module documentation, Volume 2--for the functional module documentation, and Volume 3 for the documentation of the data libraries and subroutine libraries.

  13. SCALE: A modular code system for performing standardized computer analyses for licensing evaluation. Control modules -- Volume 1, Revision 4

    Energy Technology Data Exchange (ETDEWEB)

    Landers, N.F.; Petrie, L.M.; Knight, J.R. [Oak Ridge National Lab., TN (United States)] [and others

    1995-04-01

    SCALE--a modular code system for Standardized Computer Analyses Licensing Evaluation--has been developed by Oak Ridge National Laboratory at the request of the US Nuclear Regulatory Commission. The SCALE system utilizes well-established computer codes and methods within standard analysis sequences that (1) allow an input format designed for the occasional user and/or novice, (2) automate the data processing and coupling between modules, and (3) provide accurate and reliable results. System development has been directed at problem-dependent cross-section processing and analysis of criticality safety, shielding, heat transfer, and depletion/decay problems. Since the initial release of SCALE in 1980, the code system has been heavily used for evaluation of nuclear fuel facility and package designs. This revision documents Version 4.2 of the system. This manual is divided into three volumes: Volume 1--for the control module documentation, Volume 2--for the functional module documentation, and Volume 3 for the documentation of the data libraries and subroutine libraries.

  14. Combinatorial Control of mRNA Fates by RNA-Binding Proteins and Non-Coding RNAs

    Directory of Open Access Journals (Sweden)

    Valentina Iadevaia

    2015-09-01

    Full Text Available Post-transcriptional control of gene expression is mediated by RNA-binding proteins (RBPs and small non-coding RNAs (e.g., microRNAs that bind to distinct elements in their mRNA targets. Here, we review recent examples describing the synergistic and/or antagonistic effects mediated by RBPs and miRNAs to determine the localisation, stability and translation of mRNAs in mammalian cells. From these studies, it is becoming increasingly apparent that dynamic rearrangements of RNA-protein complexes could have profound implications in human cancer, in synaptic plasticity, and in cellular differentiation.

  15. Visual-based quadrotor control by means of fuzzy cognitive maps.

    Science.gov (United States)

    Amirkhani, Abdollah; Shirzadeh, Masoud; Papageorgiou, Elpiniki I; Mosavi, Mohammad R

    2016-01-01

    By applying an image-based visual servoing (IBVS) method, the intelligent image-based controlling of a quadrotor type unmanned aerial vehicle (UAV) tracking a moving target is studied in this paper. A fuzzy cognitive map (FCM) is a soft computing method which is classified as a fuzzy neural system and exploits the main aspects of fuzzy logic and neural network systems; so it seems to be a suitable choice for implementing a vision-based intelligent technique. An FCM has been employed in implementing an IBVS scheme on a quadrotor UAV, so that the UAV can track a moving target on the ground. For this purpose, by properly combining the perspective image moments, some features with the desired characteristics for controlling the translational and yaw motions of a UAV have been presented. In designing a vision-based control method for a UAV quadrotor, there are some challenges, including the target mobility and not knowing the height of UAV above the target. Also, no sensor has been installed on the moving object and the changes of its yaw angle are not available. Despite all the stated challenges, the proposed method, which uses an FCM in controlling the translational motion and the yaw rotation of a UAV, adequately enables the quadrotor to follow the moving target. The simulation results for different paths show the satisfactory performance of the designed controller. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  16. Effects of interactive visual feedback training on post-stroke pusher syndrome: a pilot randomized controlled study.

    Science.gov (United States)

    Yang, Yea-Ru; Chen, Yi-Hua; Chang, Heng-Chih; Chan, Rai-Chi; Wei, Shun-Hwa; Wang, Ray-Yau

    2015-10-01

    We investigated the effects of a computer-generated interactive visual feedback training program on the recovery from pusher syndrome in stroke patients. Assessor-blinded, pilot randomized controlled study. A total of 12 stroke patients with pusher syndrome were randomly assigned to either the experimental group (N = 7, computer-generated interactive visual feedback training) or control group (N = 5, mirror visual feedback training). The scale for contraversive pushing for severity of pusher syndrome, the Berg Balance Scale for balance performance, and the Fugl-Meyer assessment scale for motor control were the outcome measures. Patients were assessed pre- and posttraining. A comparison of pre- and posttraining assessment results revealed that both training programs led to the following significant changes: decreased severity of pusher syndrome scores (decreases of 4.0 ± 1.1 and 1.4 ± 1.0 in the experimental and control groups, respectively); improved balance scores (increases of 14.7 ± 4.3 and 7.2 ± 1.6 in the experimental and control groups, respectively); and higher scores for lower extremity motor control (increases of 8.4 ± 2.2 and 5.6 ± 3.3 in the experimental and control groups, respectively). Furthermore, the computer-generated interactive visual feedback training program produced significantly better outcomes in the improvement of pusher syndrome (p visual feedback training program. Although both training programs were beneficial, the computer-generated interactive visual feedback training program more effectively aided recovery from pusher syndrome compared with mirror visual feedback training. © The Author(s) 2014.

  17. Regulating outdoor advertisement boards; employing spatial decision support system to control urban visual pollution

    Science.gov (United States)

    Wakil, K.; Hussnain, MQ; Tahir, A.; Naeem, M. A.

    2016-06-01

    Unmanaged placement, size, location, structure and contents of outdoor advertisement boards have resulted in severe urban visual pollution and deterioration of the socio-physical living environment in urban centres of Pakistan. As per the regulatory instruments, the approval decision for a new advertisement installation is supposed to be based on the locational density of existing boards and their proximity or remoteness to certain land- uses. In cities, where regulatory tools for the control of advertisement boards exist, responsible authorities are handicapped in effective implementation due to the absence of geospatial analysis capacity. This study presents the development of a spatial decision support system (SDSS) for regularization of advertisement boards in terms of their location and placement. The knowledge module of the proposed SDSS is based on provisions and restrictions prescribed in regulatory documents. While the user interface allows visualization and scenario evaluation to understand if the new board will affect existing linear density on a particular road and if it violates any buffer restrictions around a particular land use. Technically the structure of the proposed SDSS is a web-based solution which includes open geospatial tools such as OpenGeo Suite, GeoExt, PostgreSQL, and PHP. It uses three key data sets including road network, locations of existing billboards and building parcels with land use information to perform the analysis. Locational suitability has been calculated using pairwise comparison through analytical hierarchy process (AHP) and weighted linear combination (WLC). Our results indicate that open geospatial tools can be helpful in developing an SDSS which can assist solving space related iterative decision challenges on outdoor advertisements. Employing such a system will result in effective implementation of regulations resulting in visual harmony and aesthetic improvement in urban communities.

  18. A comparison of kinesthetic-tactual and visual displays via a critical tracking task. [for aircraft control

    Science.gov (United States)

    Jagacinski, R. J.; Miller, D. P.; Gilson, R. D.

    1979-01-01

    The feasibility of using the critical tracking task to evaluate kinesthetic-tactual displays was examined. The test subjects were asked to control a first-order unstable system with a continuously decreasing time constant by using either visual or tactual unidimensional displays. The results indicate that the critical tracking task is both a feasible and a reliable methodology for assessing tactual tracking. Further, that the critical tracking methodology is as sensitive and valid a measure of tactual tracking as visual tracking is demonstrated by the approximately equal effects of quickening for the tactual and visual displays.

  19. Wind Farm Stabilization by using DFIG with Current Controlled Voltage Source Converters Taking Grid Codes into Consideration

    Science.gov (United States)

    Okedu, Kenneth Eloghene; Muyeen, S. M.; Takahashi, Rion; Tamura, Junji

    Recent wind farm grid codes require wind generators to ride through voltage sags, which means that normal power production should be re-initiated once the nominal grid voltage is recovered. However, fixed speed wind turbine generator system using induction generator (IG) has the stability problem similar to the step-out phenomenon of a synchronous generator. On the other hand, doubly fed induction generator (DFIG) can control its real and reactive powers independently while being operated in variable speed mode. This paper proposes a new control strategy using DFIGs for stabilizing a wind farm composed of DFIGs and IGs, without incorporating additional FACTS devices. A new current controlled voltage source converter (CC-VSC) scheme is proposed to control the converters of DFIG and the performance is verified by comparing the results with those of voltage controlled voltage source converter (VC-VSC) scheme. Another salient feature of this study is to reduce the number of proportionate integral (PI) controllers used in the rotor side converter without degrading dynamic and transient performances. Moreover, DC-link protection scheme during grid fault can be omitted in the proposed scheme which reduces overall cost of the system. Extensive simulation analyses by using PSCAD/EMTDC are carried out to clarify the effectiveness of the proposed CC-VSC based control scheme of DFIGs.

  20. Closed-loop response properties of a visual interneuron involved in fly optomotor control

    Directory of Open Access Journals (Sweden)

    Naveed eEjaz

    2013-03-01

    Full Text Available Due to methodological limitations neural function is mostly studied under open-loop conditions. Normally, however, nervous systems operate in closed-loop where sensory input is processed to generate behavioural outputs, which again change the sensory input. Here, we investigate the closed-loop responses of an identified visual interneuron, the blowfly H1-cell, that is part of a neural circuit involved in optomotor flight and gaze control. Those behaviours may be triggered by attitude changes during flight in turbulent air. The fly analyses the resulting retinal image shifts and performs compensatory body and head rotations to regain its default attitude. We developed a fly-robot interface to study H1-cell responses in a 1 degree-of-freedom image stabilization task. Image shifts, induced by externally forced rotations, modulate the cell’s spike rate that controls counter rotations of a mobile robot to minimize relative motion between the robot and its visual surroundings. A feedback controller closed the loop between neural activity and the rotation of the robot. Under these conditions we found the following H1-cell response properties: (i the peak spike rate decreases when the mean image velocity is increased, (ii the relationship between spike rate and image velocity depends on the standard deviation of the image velocities suggesting adaptive scaling of the cell’s signalling range, and (iii the cell’s gain decreases linearly with increasing image accelerations.Our results reveal a remarkable qualitative similarity between the response dynamics of the H1-cell under closed-loop conditions with those obtained in previous open-loop experiments. Finally, we show that the adaptive scaling of the H1-cell’s responses, while maximizing information on image velocity, decreases the cell’s sensitivity to image accelerations. Understanding such trade-offs in biological vision systems may advance the design of smart vision sensors for autonomous

  1. Closed-loop response properties of a visual interneuron involved in fly optomotor control.

    Science.gov (United States)

    Ejaz, Naveed; Krapp, Holger G; Tanaka, Reiko J

    2013-01-01

    Due to methodological limitations neural function is mostly studied under open-loop conditions. Normally, however, nervous systems operate in closed-loop where sensory input is processed to generate behavioral outputs, which again change the sensory input. Here, we investigate the closed-loop responses of an identified visual interneuron, the blowfly H1-cell, that is part of a neural circuit involved in optomotor flight and gaze control. Those behaviors may be triggered by attitude changes during flight in turbulent air. The fly analyses the resulting retinal image shifts and performs compensatory body and head rotations to regain its default attitude. We developed a fly robot interface to study H1-cell responses in a 1 degree-of-freedom image stabilization task. Image shifts, induced by externally forced rotations, modulate the cell's spike rate that controls counter rotations of a mobile robot to minimize relative motion between the robot and its visual surroundings. A feedback controller closed the loop between neural activity and the rotation of the robot. Under these conditions we found the following H1-cell response properties: (i) the peak spike rate decreases when the mean image velocity is increased, (ii) the relationship between spike rate and image velocity depends on the standard deviation of the image velocities suggesting adaptive scaling of the cell's signaling range, and (iii) the cell's gain decreases linearly with increasing image accelerations. Our results reveal a remarkable qualitative similarity between the response dynamics of the H1-cell under closed-loop conditions with those obtained in previous open-loop experiments. Finally, we show that the adaptive scaling of the H1-cell's responses, while maximizing information on image velocity, decreases the cell's sensitivity to image accelerations. Understanding such trade-offs in biological vision systems may advance the design of smart vision sensors for autonomous robots.

  2. Pondering on Executing the Poll Code by Utilizing the CPU's Serialized Code in VB%在Visual Basic中利用CPU序列号制作注册码

    Institute of Scientific and Technical Information of China (English)

    陈燊

    2008-01-01

    利用Visual Basic制作的软件加密方法根据用户计算机中的唯一硬件参数生成注册码.可以防止注册码的盗用问题.阐述了在Visual Basic中读取用户计算机的CPU序列号,在用户计算机上产生随机数同时作为关键文件(数据库)数据项的方法,实现对软件著作权的保护.

  3. La mise en oeuvre des codes d'éthique par le control interne

    NARCIS (Netherlands)

    van der Elst, C.F.

    2014-01-01

    The real value of the internal control system lies in the animation of the ethical values in the organization. The integration of ethical risks in the internal control process enables the moving notions of ethical behaviour and accommodate the training and inducement programs of all employees accord

  4. Control-theoretic Approach to Communication with Feedback: Fundamental Limits and Code Design

    CERN Document Server

    Ardestanizadeh, Ehsan

    2010-01-01

    Feedback communication is studied from a control-theoretic perspective, mapping the communication problem to a control problem in which the control signal is received through the same noisy channel as in the communication problem, and the (nonlinear and time-varying) dynamics of the system determine a subclass of encoders available at the transmitter. The MMSE capacity is defined to be the supremum exponential decay rate of the mean square decoding error. This is upper bounded by the information-theoretic feedback capacity, which is the supremum of the achievable rates. A sufficient condition is provided under which the upper bound holds with equality. For the special class of stationary Gaussian channels, a simple application of Bode's integral formula shows that the feedback capacity, recently characterized by Kim, is equal to the maximum instability that can be tolerated by the controller under a given power constraint. Finally, the control mapping is generalized to the N-sender AWGN multiple access channe...

  5. Plataforma de desarrollo para el control en tiempo real de estructuras cinemáticas con realimentación visual//Platform to develop real time visual servoing control in kinematics systems

    Directory of Open Access Journals (Sweden)

    René González-Rodríguez

    2012-09-01

    Full Text Available En este trabajo se presenta una plataforma de desarrollo para el control en tiempo real de estructuras cinemáticas con realimentación visual. Se ha diseñado una configuración genérica que permite la implementación de cualquier variante de control visual. Para el procesamiento de la imagen se ha propuesto una estrategia que permite el uso de diferentes herramientas comerciales o algoritmos propiospara la captura y extracción de características de la imagen. El uso de Real Time Work Shop y Real Time Windows Target en el lazo de control interno brinda la posibilidad de implementar algoritmos de control servovisual en tiempo real. Al final del trabajo se presentan los resultados de un esquema de controlservovisual aplicado en un manipulador industrial. La plataforma propuesta constituye una herramienta de desarrollo para aplicaciones industriales de control servovisual y sirve de apoyo a la enseñanza de la mecatrónica en pregrado y postgrado.Palabras claves: control servovisual, control en tiempo real, estructuras cinemáticas._______________________________________________________________________________AbstractIn this work we propose a platform to develop visual servoing control systems. The platform has a generic design with the possibility to implement direct or look and move visual servoing systems. For the image processing we present a generic design allowing the use of any image processing library like Matrox MIL,Intel IPP, OpenCV or any algorithms for image capture and target characteristics extraction. The uses of Real Time Work Shop and Real Time Windows Target in the internal loop permits modify the control structure in SIMULINK very easy.Key words: visual servoing, real time control, kinematics systems.

  6. Visualized Multiprobe Electrical Impedance Measurements with STM Tips Using Shear Force Feedback Control

    Directory of Open Access Journals (Sweden)

    Luis Botaya

    2016-05-01

    Full Text Available Here we devise a multiprobe electrical measurement system based on quartz tuning forks (QTFs and metallic tips capable of having full 3D control over the position of the probes. The system is based on the use of bent tungsten tips that are placed in mechanical contact (glue-free solution with a QTF sensor. Shear forces acting in the probe are measured to control the tip-sample distance in the Z direction. Moreover, the tilting of the tip allows the visualization of the experiment under the optical microscope, allowing the coordination of the probes in X and Y directions. Meanwhile, the metallic tips are connected to a current–voltage amplifier circuit to measure the currents and thus the impedance of the studied samples. We discuss here the different aspects that must be addressed when conducting these multiprobe experiments, such as the amplitude of oscillation, shear force distance control, and wire tilting. Different results obtained in the measurement of calibration samples and microparticles are presented. They demonstrate the feasibility of the system to measure the impedance of the samples with a full 3D control on the position of the nanotips.

  7. Non-coding transcripts in the H19 imprinting control region mediate gene silencing in transgenic Drosophila.

    Science.gov (United States)

    Schoenfelder, Stefan; Smits, Guillaume; Fraser, Peter; Reik, Wolf; Paro, Renato

    2007-11-01

    The imprinting control region (ICR) upstream of H19 is the key regulatory element conferring monoallelic expression on H19 and Igf2 (insulin-like growth factor 2). Epigenetic marks in the ICR regulate its interaction with the chromatin protein CCCTC-binding factor and with other control factors to coordinate gene silencing in the imprinting cluster. Here, we show that the H19 ICR is biallelically transcribed, producing both sense and antisense RNAs. We analyse the function of the non-coding transcripts in a Drosophila transgenic system in which the H19 upstream region silences the expression of a reporter gene. We show that knockdown of H19 ICR non-coding RNA (ncRNA) by RNA interference leads to the loss of reporter gene silencing. Our results are, to the best of our knowledge, the first to show that ncRNAs in the H19 ICR are functionally significant, and also indicate that they have a role in regulating gene expression and perhaps epigenetic marks at the H19/Igf2 locus.

  8. RNA exosome-regulated long non-coding RNA transcription controls super-enhancer activity.

    Science.gov (United States)

    Pefanis, Evangelos; Wang, Jiguang; Rothschild, Gerson; Lim, Junghyun; Kazadi, David; Sun, Jianbo; Federation, Alexander; Chao, Jaime; Elliott, Oliver; Liu, Zhi-Ping; Economides, Aris N; Bradner, James E; Rabadan, Raul; Basu, Uttiya

    2015-05-01

    We have ablated the cellular RNA degradation machinery in differentiated B cells and pluripotent embryonic stem cells (ESCs) by conditional mutagenesis of core (Exosc3) and nuclear RNase (Exosc10) components of RNA exosome and identified a vast number of long non-coding RNAs (lncRNAs) and enhancer RNAs (eRNAs) with emergent functionality. Unexpectedly, eRNA-expressing regions accumulate R-loop structures upon RNA exosome ablation, thus demonstrating the role of RNA exosome in resolving deleterious DNA/RNA hybrids arising from active enhancers. We have uncovered a distal divergent eRNA-expressing element (lncRNA-CSR) engaged in long-range DNA interactions and regulating IgH 3' regulatory region super-enhancer function. CRISPR-Cas9-mediated ablation of lncRNA-CSR transcription decreases its chromosomal looping-mediated association with the IgH 3' regulatory region super-enhancer and leads to decreased class switch recombination efficiency. We propose that the RNA exosome protects divergently transcribed lncRNA expressing enhancers by resolving deleterious transcription-coupled secondary DNA structures, while also regulating long-range super-enhancer chromosomal interactions important for cellular function.

  9. A conserved influenza A virus nucleoprotein code controls specific viral genome packaging

    Science.gov (United States)

    Moreira, Étori Aguiar; Weber, Anna; Bolte, Hardin; Kolesnikova, Larissa; Giese, Sebastian; Lakdawala, Seema; Beer, Martin; Zimmer, Gert; García-Sastre, Adolfo; Schwemmle, Martin; Juozapaitis, Mindaugas

    2016-01-01

    Packaging of the eight genomic RNA segments of influenza A viruses (IAV) into viral particles is coordinated by segment-specific packaging sequences. How the packaging signals regulate the specific incorporation of each RNA segment into virions and whether other viral or host factors are involved in this process is unknown. Here, we show that distinct amino acids of the viral nucleoprotein (NP) are required for packaging of specific RNA segments. This was determined by studying the NP of a bat influenza A-like virus, HL17NL10, in the context of a conventional IAV (SC35M). Replacement of conserved SC35M NP residues by those of HL17NL10 NP resulted in RNA packaging defective IAV. Surprisingly, substitution of these conserved SC35M amino acids with HL17NL10 NP residues led to IAV with altered packaging efficiencies for specific subsets of RNA segments. This suggests that NP harbours an amino acid code that dictates genome packaging into infectious virions. PMID:27650413

  10. The histone code reader SPIN1 controls RET signaling in liposarcoma.

    Science.gov (United States)

    Franz, Henriette; Greschik, Holger; Willmann, Dominica; Ozretić, Luka; Jilg, Cordula Annette; Wardelmann, Eva; Jung, Manfred; Buettner, Reinhard; Schüle, Roland

    2015-03-10

    The histone code reader Spindlin1 (SPIN1) has been implicated in tumorigenesis and tumor growth, but the underlying molecular mechanisms remain poorly understood. Here, we show that reducing SPIN1 levels strongly impairs proliferation and increases apoptosis of liposarcoma cells in vitro and in xenograft mouse models. Combining signaling pathway, genome-wide chromatin binding, and transcriptome analyses, we found that SPIN1 directly enhances expression of GDNF, an activator of the RET signaling pathway, in cooperation with the transcription factor MAZ. Accordingly, knockdown of SPIN1 or MAZ results in reduced levels of GDNF and activated RET explaining diminished liposarcoma cell proliferation and survival. In line with these observations, levels of SPIN1, GDNF, activated RET, and MAZ are increased in human liposarcoma compared to normal adipose tissue or lipoma. Importantly, a mutation of SPIN1 within the reader domain interfering with chromatin binding reduces liposarcoma cell proliferation and survival. Together, our data describe a molecular mechanism for SPIN1 function in liposarcoma and suggest that targeting SPIN1 chromatin association with small molecule inhibitors may represent a novel therapeutic strategy.

  11. Biometrics based key management of double random phase encoding scheme using error control codes

    Science.gov (United States)

    Saini, Nirmala; Sinha, Aloka

    2013-08-01

    In this paper, an optical security system has been proposed in which key of the double random phase encoding technique is linked to the biometrics of the user to make it user specific. The error in recognition due to the biometric variation is corrected by encoding the key using the BCH code. A user specific shuffling key is used to increase the separation between genuine and impostor Hamming distance distribution. This shuffling key is then further secured using the RSA public key encryption to enhance the security of the system. XOR operation is performed between the encoded key and the feature vector obtained from the biometrics. The RSA encoded shuffling key and the data obtained from the XOR operation are stored into a token. The main advantage of the present technique is that the key retrieval is possible only in the simultaneous presence of the token and the biometrics of the user which not only authenticates the presence of the original input but also secures the key of the system. Computational experiments showed the effectiveness of the proposed technique for key retrieval in the decryption process by using the live biometrics of the user.

  12. Generic Ada code in the NASA space station command, control and communications environment

    Science.gov (United States)

    Mcdougall, D. P.; Vollman, T. E.

    1986-01-01

    The results of efforts to apply powerful Ada constructs to the formatted message handling process are described. The goal of these efforts was to extend the state-of-technology in message handling while at the same time producing production-quality, reusable code. The first effort was initiated in September, 1984 and delivered in April, 1985. That product, the Generic Message Handling Facility, met initial goals, was reused, and is available in the Ada Repository on ARPANET. However, it became apparent during its development that the initial approach to building a message handler template was not optimal. As a result of this initial effort, several alternate approaches were identified, and research is now on-going to identify an improved product. The ultimate goal is to be able to instantly build a message handling system for any message format given a specification of that message format. The problem lies in how to specify the message format, and one that is done, how to use that information to build the message handler. Message handling systems and message types are described. The initial efforts, its results and its shortcomings are detailed. The approach now being taken to build a system which will be significantly easier to implement, and once implemented, easier to use, is described. Finally, conclusions are offered.

  13. The critical phase for visual control of human walking over complex terrain

    Science.gov (United States)

    Matthis, Jonathan Samir; Barton, Sean L.; Fajen, Brett R.

    2017-01-01

    To walk efficiently over complex terrain, humans must use vision to tailor their gait to the upcoming ground surface without interfering with the exploitation of passive mechanical forces. We propose that walkers use visual information to initialize the mechanical state of the body before the beginning of each step so the resulting ballistic trajectory of the walker’s center-of-mass will facilitate stepping on target footholds. Using a precision stepping task and synchronizing target visibility to the gait cycle, we empirically validated two predictions derived from this strategy: (1) Walkers must have information about upcoming footholds during the second half of the preceding step, and (2) foot placement is guided by information about the position of the target foothold relative to the preceding base of support. We conclude that active and passive modes of control work synergistically to allow walkers to negotiate complex terrain with efficiency, stability, and precision. PMID:28739912

  14. Hierarchical structural control of visual properties in self-assembled photonic-plasmonic pigments

    CERN Document Server

    Koay, Natalie; Kay, Theresa M; Nerger, Bryan A; Miles-Rossouw, Malaika; Shirman, Tanya; Vu, Thy L; England, Grant; Phillips, Katherine R; Utech, Stefanie; Vogel, Nicolas; Kolle, Mathias; Aizenberg, Joanna

    2014-01-01

    We present a simple one-pot co-assembly method for the synthesis of hierarchically structured pigment particles consisting of silica inverse-opal bricks that are doped with plasmonic absorbers. We study the interplay between the plasmonic and photonic resonances and their effect on the visual appearance of macroscopic collections of photonic bricks that are distributed in randomized orientations. Manipulating the pore geometry tunes the wavelength- and angle-dependence of the scattering profile, which can be engineered to produce angle-dependent Bragg resonances that can either enhance or contrast with the color produced by the plasmonic absorber. By controlling the overall dimensions of the photonic bricks and their aspect ratios, their preferential alignment can either be encouraged or suppressed. This causes the Bragg resonance to appear either as uniform color travel in the former case or as sparse iridescent sparkle in the later case. By manipulating the surface chemistry of these photonic bricks, which ...

  15. Realizing precision pulse TIG welding with arc length control and visual image sensing based weld detection

    Institute of Scientific and Technical Information of China (English)

    孙振国; 陈念; 陈强

    2003-01-01

    Methods of arc length control and visual image based weld detection for precision pulse TIG welding were investigated. With a particular all-hardware circuit, arc voltage during peak current stage is sampled and integrated to indicate arc length, deviation of arc length and adjusting parameters are calculated and output to drive a step motor directly. According to the features of welding image grabbed with CCD camera, a special algorithm was developed to detect the central line of weld fast and accurately. Then an application system were established, whose static arc length error is ±0.1 mm with 20 A average current and 1 mm given arc length, static detection precision of weld is 0.01 mm, processing time of each image is less than 120 ms. Precision pulse TIG welding of some given thin stainless steel components with complicated curved surface was successfully realized.

  16. Utilization of a labeled tracking oligonucleotide for visualization and quality control of spotted 70-mer arrays

    Directory of Open Access Journals (Sweden)

    Khan Shehnaz

    2004-02-01

    Full Text Available Abstract Background Spotted 70-mer oligonucleotide arrays offer potentially greater specificity and an alternative to expensive cDNA library maintenance and amplification. Since microarray fabrication is a considerable source of data variance, we previously directly tagged cDNA probes with a third fluorophore for prehybridization quality control. Fluorescently modifying oligonucleotide sets is cost prohibitive, therefore, a co-spotted Staphylococcus aureus-specific fluorescein-labeled "tracking" oligonucleotide is described to monitor fabrication variables of a Mycobacterium tuberculosis oligonucleotide microarray. Results Significantly (p M. tuberculosis H37Rv and M. tuberculosis mprA. Linearity between the mean log Cy3/Cy5 ratios of genes differentially expressed from arrays either possessing or lacking the tracking oligonucleotide was observed (R2 = 0.90, p Conclusions This novel approach enables prehybridization array visualization for spotted oligonucleotide arrays and sets the stage for more sophisticated slide qualification and data filtering applications.

  17. The critical phase for visual control of human walking over complex terrain.

    Science.gov (United States)

    Matthis, Jonathan Samir; Barton, Sean L; Fajen, Brett R

    2017-08-08

    To walk efficiently over complex terrain, humans must use vision to tailor their gait to the upcoming ground surface without interfering with the exploitation of passive mechanical forces. We propose that walkers use visual information to initialize the mechanical state of the body before the beginning of each step so the resulting ballistic trajectory of the walker's center-of-mass will facilitate stepping on target footholds. Using a precision stepping task and synchronizing target visibility to the gait cycle, we empirically validated two predictions derived from this strategy: (1) Walkers must have information about upcoming footholds during the second half of the preceding step, and (2) foot placement is guided by information about the position of the target foothold relative to the preceding base of support. We conclude that active and passive modes of control work synergistically to allow walkers to negotiate complex terrain with efficiency, stability, and precision.

  18. Benefit of bi-ocular visual stimulation for postural control in children with strabismus.

    Science.gov (United States)

    Gaertner, Chrystal; Creux, Charlotte; Espinasse-Berrod, Marie-Andrée; Orssaud, Christophe; Dufier, Jean-Louis; Kapoula, Zoï

    2013-01-01

    Vision is important for postural control as is shown by the Romberg quotient (RQ): with eyes closed, postural instability increases relative to eyes open (RQ = 2). Yet while fixating at far distance, postural stability is similar with eyes open and eyes closed (RQ = 1). Postural stability can be better with both eyes viewing than one eye, but such effect is not consistent among healthy subjects. The first goal of the study is to test the RQ as a function of distance for children with convergent versus divergent strabismus. The second goal is to test whether vision from two eyes relative to vision from one eye provides better postural stability. Thirteen children with divergent strabismus and eleven with convergent strabismus participated in this study. Posturtography was done with the Techno concept device. Experiment 1, four conditions: fixation at 40 cm and at 200 cm both with eyes open and eyes covered (evaluation of RQ). Experiment 2, six conditions: fixation at 40 cm and at 200 cm, with both eyes viewing or under monocular vision (dominant and non-dominant eye). For convergent strabismus, the groups mean value of RQ was 1.3 at near and 0.94 at far distance; for divergent, it was 1.06 at near and 1.68 at far. For all children, the surface of body sway was significantly smaller under both eyes viewing than monocular viewing (either eye). Increased RQ value at near for convergent and at far for divergent strabismus is attributed to the influence of the default strabismus angle and to better use of ocular motor signals. Vision with the two eyes improves postural control for both viewing distances and for both types of strabismus. Such benefit can be due to complementary mechanisms: larger visual field, better quality of fixation and vergence angle due to the use of visual inputs from both eyes.

  19. Benefit of bi-ocular visual stimulation for postural control in children with strabismus.

    Directory of Open Access Journals (Sweden)

    Chrystal Gaertner

    Full Text Available Vision is important for postural control as is shown by the Romberg quotient (RQ: with eyes closed, postural instability increases relative to eyes open (RQ = 2. Yet while fixating at far distance, postural stability is similar with eyes open and eyes closed (RQ = 1. Postural stability can be better with both eyes viewing than one eye, but such effect is not consistent among healthy subjects. The first goal of the study is to test the RQ as a function of distance for children with convergent versus divergent strabismus. The second goal is to test whether vision from two eyes relative to vision from one eye provides better postural stability. Thirteen children with divergent strabismus and eleven with convergent strabismus participated in this study. Posturtography was done with the Techno concept device. Experiment 1, four conditions: fixation at 40 cm and at 200 cm both with eyes open and eyes covered (evaluation of RQ. Experiment 2, six conditions: fixation at 40 cm and at 200 cm, with both eyes viewing or under monocular vision (dominant and non-dominant eye. For convergent strabismus, the groups mean value of RQ was 1.3 at near and 0.94 at far distance; for divergent, it was 1.06 at near and 1.68 at far. For all children, the surface of body sway was significantly smaller under both eyes viewing than monocular viewing (either eye. Increased RQ value at near for convergent and at far for divergent strabismus is attributed to the influence of the default strabismus angle and to better use of ocular motor signals. Vision with the two eyes improves postural control for both viewing distances and for both types of strabismus. Such benefit can be due to complementary mechanisms: larger visual field, better quality of fixation and vergence angle due to the use of visual inputs from both eyes.

  20. Standardizing visual control devices for tsetse flies: east African Species Glossina fuscipes fuscipes and Glossina tachinoides.

    Directory of Open Access Journals (Sweden)

    Francis Oloo

    2014-11-01

    Full Text Available Riverine species of tsetse are responsible for most human African trypanosomiasis (HAT transmission and are also important vectors of animal trypanosomiasis. This study concerns the development of visual control devices for two such species, Glossina fuscipes fuscipes and Glossina tachinoides, at the eastern limits of their continental range. The goal was to determine the most long-lasting, practical and cost-effective visually attractive device that induces the strongest landing responses in these species for use as insecticide-impregnated tools in vector population suppression.Field trials were conducted in different seasons on G. f. fuscipes in Kenya, Ethiopia and the Sudan and on G. tachinoides in Ethiopia to measure the performance of traps and 2D targets of different sizes and colours, with and without chemical baits, at different population densities and under different environmental conditions. Adhesive film was used to enumerate flies at these remote locations to compare trapping efficiencies. The findings show that targets made from black and blue fabrics (either phthalogen or turquoise covered with adhesive film render them equal to or more efficient than traps at capturing G. f. fuscipes and G. tachinoides. Biconical trap efficiency varied between 25% and 33% for the two species. Smaller 0.25 m×0.25 m phthalogen blue-black targets proved more efficient than the regular 1 m2 target for both species, by over six times for Glossina f. fuscipes and two times for G. tachinoides based on catches per m2. Overall, targets with a higher edge/surface area ratio were more efficient at capturing flies.Taking into account practical considerations and fly preferences for edges and colours, we propose a 0.5×0.75 m blue-black target as a simple cost-effective device for management of G. f. fuscipes and G. tachinoides, impregnated with insecticide for control and covered with adhesive film for population sampling.

  1. Effects of Anodal Transcranial Direct Current Stimulation on Visually Guided Learning of Grip Force Control

    Directory of Open Access Journals (Sweden)

    Tamas Minarik

    2015-03-01

    Full Text Available Anodal transcranial Direct Current Stimulation (tDCS has been shown to be an effective non-invasive brain stimulation method for improving cognitive and motor functioning in patients with neurological deficits. tDCS over motor cortex (M1, for instance, facilitates motor learning in stroke patients. However, the literature on anodal tDCS effects on motor learning in healthy participants is inconclusive, and the effects of tDCS on visuo-motor integration are not well understood. In the present study we examined whether tDCS over the contralateral motor cortex enhances learning of grip-force output in a visually guided feedback task in young and neurologically healthy volunteers. Twenty minutes of 1 mA anodal tDCS were applied over the primary motor cortex (M1 contralateral to the dominant (right hand, during the first half of a 40 min power-grip task. This task required the control of a visual signal by modulating the strength of the power-grip for six seconds per trial. Each participant completed a two-session sham-controlled crossover protocol. The stimulation conditions were counterbalanced across participants and the sessions were one week apart. Performance measures comprised time-on-target and target-deviation, and were calculated for the periods of stimulation (or sham and during the afterphase respectively. Statistical analyses revealed significant performance improvements over the stimulation and the afterphase, but this learning effect was not modulated by tDCS condition. This suggests that the form of visuomotor learning taking place in the present task was not sensitive to neurostimulation. These null effects, together with similar reports for other types of motor tasks, lead to the proposition that tDCS facilitation of motor learning might be restricted to cases or situations where the motor system is challenged, such as motor deficits, advanced age, or very high task demand.

  2. The role of online visual feedback for the control of target-directed and allocentric hand movements.

    Science.gov (United States)

    Thaler, Lore; Goodale, Melvyn A

    2011-02-01

    Studies that have investigated how sensory feedback about the moving hand is used to control hand movements have relied on paradigms such as pointing or reaching that require subjects to acquire target locations. In the context of these target-directed tasks, it has been found repeatedly that the human sensory-motor system relies heavily on visual feedback to control the ongoing movement. This finding has been formalized within the framework of statistical optimality according to which different sources of sensory feedback are combined such as to minimize variance in sensory information during movement control. Importantly, however, many hand movements that people perform every day are not target-directed, but based on allocentric (object-centered) visual information. Examples of allocentric movements are gesture imitation, drawing, or copying. Here we tested if visual feedback about the moving hand is used in the same way to control target-directed and allocentric hand movements. The results show that visual feedback is used significantly more to reduce movement scatter in the target-directed as compared with the allocentric movement task. Furthermore, we found that differences in the use of visual feedback between target-directed and allocentric hand movements cannot be explained based on differences in uncertainty about the movement goal. We conclude that the role played by visual feedback for movement control is fundamentally different for target-directed and allocentric movements. The results suggest that current computational and neural models of sensorimotor control that are based entirely on data derived from target-directed paradigms have to be modified to accommodate performance in the allocentric tasks used in our experiments. As a consequence, the results cast doubt on the idea that models of sensorimotor control developed exclusively from data obtained in target-directed paradigms are also valid in the context of allocentric tasks, such as drawing

  3. 2-D Circulation Control Airfoil Benchmark Experiments Intended for CFD Code Validation

    Science.gov (United States)

    Englar, Robert J.; Jones, Gregory S.; Allan, Brian G.; Lin, Johb C.

    2009-01-01

    A current NASA Research Announcement (NRA) project being conducted by Georgia Tech Research Institute (GTRI) personnel and NASA collaborators includes the development of Circulation Control (CC) blown airfoils to improve subsonic aircraft high-lift and cruise performance. The emphasis of this program is the development of CC active flow control concepts for both high-lift augmentation, drag control, and cruise efficiency. A collaboration in this project includes work by NASA research engineers, whereas CFD validation and flow physics experimental research are part of NASA s systematic approach to developing design and optimization tools for CC applications to fixed-wing aircraft. The design space for CESTOL type aircraft is focusing on geometries that depend on advanced flow control technologies that include Circulation Control aerodynamics. The ability to consistently predict advanced aircraft performance requires improvements in design tools to include these advanced concepts. Validation of these tools will be based on experimental methods applied to complex flows that go beyond conventional aircraft modeling techniques. This paper focuses on recent/ongoing benchmark high-lift experiments and CFD efforts intended to provide 2-D CFD validation data sets related to NASA s Cruise Efficient Short Take Off and Landing (CESTOL) study. Both the experimental data and related CFD predictions are discussed.

  4. Visual C++实现旧代码向Windows应用转换的几种方法%Achieving the Conversion from Old Codes to Applying Process of Windows with Visual C++

    Institute of Scientific and Technical Information of China (English)

    侯丹林; 王飞; 范翠香

    2001-01-01

    Visual C++是目前对Windows进行应用程序开发的最好工具,在软件工程开发中得到了越来越广泛的应用。从其它开发环境转到Visual C++开发环境,会存在原有应用程序向Windows应用转换的问题,本文主要介绍在Visual C++中实现这种转换的几种方法。%Today Visual C++ is the best tool in the development of applying process of windows. It has been wildly used in the development of software engineering. When turning to the development environment of Visual C++ from other development environments, there should be problems of changing the old applying process to the applying process of windows. This paper mainly introduces some methods of achieving the change with Visual C++.

  5. User manual of Visual Balan V. 1.0 Interactive code for water balances and refueling estimation; Manual del usuario del programa Visual Balan V. 1.0. Codigo interactivo para la realizacion de balances hidrologicos y la estimacion de la recarga

    Energy Technology Data Exchange (ETDEWEB)

    Samper, J.; Huguer, L.; Ares, J.; Garcia, M. A. [Universidad de La Coruna (Spain)

    1999-07-01

    This document contains the Users Manual of Visual Balan V1.0, an updated version of Visual Balan V0.0 (Samper et al., 1997). Visual Balan V1.0 performs daily water balances in the soil, the unsaturated zone and the aquifer in a user-friendly environment which facilitates both the input data process and the postprocessing of results. The main inputs of the balance are rainfall and irrigation while the outputs are surface runoff, evapotranspiration, interception, inter flow and groundwater flow. The code evaluates all these components in a sequential manner by starting with rainfall and irrigation, which must be provided by the user, and continuing with interception, surface runoff, evapotranspiration, and potential recharge (water flux crossing the bottom of the soil). This potential recharge is the input to the unsaturated zone where water can flow horizontally as subsurface flow (inter flow) or vertically as percolation into the aquifer. (Author)

  6. From Errors Treatment to Exceptions Treatment Regarding the Execution Control over Visual Basic Programs

    Directory of Open Access Journals (Sweden)

    Cristina Raluca POPESCU

    2008-01-01

    Full Text Available In order to comply with the quality standards and with the best practices, the execution of the professional programs must be rigorously controlled so that to avoid occurrence of unpredictable situations that might generate anomalies and could lead to computer blockage, forced termination of the execution and data loss. In traditional programming languages, including Visual Basic 6, the concept of error is extremely evolved. It is considered as error any situation in which the program fails to execute correctly, regardless if such anomaly is generated by a software or hardware cause. Nowadays the modern platforms, including VB.NET have introduced a new concept: exception. Unfortunately, perhaps by mistake, exception is assimilated by many IT specialists as an exceptional (extraordinary situation or a rare situation.We agree with the opinion of those IT specialists asserting that error is strictly dependant on the programmer, when he/she fails in correctly generating the application’s structures, whilst exception is a situation not fitting in the usual natural execution or as desired by the programmer or user, without meaning that it occurs more often or more rarely.Designing robust programs implies for such not to terminate abnormally or block, not even upon receiving improper parameters. Two aspects are referred to: the behavior regarding low level errors (caused by the operation system, memory allocation, reading/writing in files or hardware malfunctions and the reaction to the user’s errors, such as providing incorrect input data or incorrect use of operations in respect with their sequences. Notwithstanding what platform is used in designing the programs and regardless the controversy between the specialists, in order for the execution to be terminated under the program’s control, the commands that might generate anomalies and interruptions should be strictly monitored. Implicitly, the execution control

  7. The NCS code of practice for the quality assurance and control for volumetric modulated arc therapy

    NARCIS (Netherlands)

    Mans, Anton; Schuring, Danny; Arends, Mark P.; Vugts, Cornelia A. J. M.; Wolthaus, Jochem W. H.; Lotz, Heidi T.; Admiraal, Marjan; Louwe, Rob J. W.; Ollers, Michel C.; van de Kamer, Jeroen B.

    2016-01-01

    In 2010, the NCS (Netherlands Commission on Radiation Dosimetry) installed a subcommittee to develop guidelines for quality assurance and control for volumetric modulated arc therapy (VMAT) treatments. The report (published in 2015) has been written by Dutch medical physicists and has therefore, ine

  8. Control of bacterial chromosome replication by non-coding regions outside the origin

    DEFF Research Database (Denmark)

    Frimodt-Møller, Jakob; Charbon, Godefroid; Løbner-Olesen, Anders

    2017-01-01

    Chromosome replication in Eubacteria is initiated by initiator protein(s) binding to specific sites within the replication origin, oriC. Recently, initiator protein binding to chromosomal regions outside the origin has attracted renewed attention; as such binding sites contribute to control the f...

  9. Systems and methods to control multiple peripherals with a single-peripheral application code

    Science.gov (United States)

    Ransom, Ray M.

    2013-06-11

    Methods and apparatus are provided for enhancing the BIOS of a hardware peripheral device to manage multiple peripheral devices simultaneously without modifying the application software of the peripheral device. The apparatus comprises a logic control unit and a memory in communication with the logic control unit. The memory is partitioned into a plurality of ranges, each range comprising one or more blocks of memory, one range being associated with each instance of the peripheral application and one range being reserved for storage of a data pointer related to each peripheral application of the plurality. The logic control unit is configured to operate multiple instances of the control application by duplicating one instance of the peripheral application for each peripheral device of the plurality and partitioning a memory device into partitions comprising one or more blocks of memory, one partition being associated with each instance of the peripheral application. The method then reserves a range of memory addresses for storage of a data pointer related to each peripheral device of the plurality, and initializes each of the plurality of peripheral devices.

  10. Identification, control and visually-guided behavior for a model helicopter

    Science.gov (United States)

    Saripalli, Srikanth

    Research on unmanned aerial vehicles is motivated by applications where human intervention is impossible, risky or expensive e.g. hazardous material recovery, traffic monitoring, disaster relief support, military operations etc. Due to its vertical take-off, landing and hover capabilities, a helicopter is an attractive platform for such applications. There are significant challenges to building an autonomous robotic helicopter - these span the areas of system identification, low-level control, state estimation, and planning. Towards the goal of fully-autonomous helicopters this thesis makes the following contributions. A continuous-discrete extended Kalman filter has been developed that combines inertial data with GPS and compass data to provide estimates of the 6DOF state of the helicopter. Using this filter a model for the helicopter has been identified based on frequency response techniques. The model has been validated in flight tests on a small helicopter testbed (1.6 m rotor diameter) at speeds upto 5 m/s. Based on evidence from this model a decoupled low-level controller has been developed which is embedded in a control architecture suitable for visually-guided navigation. As a novel application, we show how such a controller can be used to perform trajectory following on the helicopter where the desired trajectories are typical spacecraft landing trajectories, and the only controls available are thrusters. This in effect, produces a low-cost testbed for testing spacecraft landing and hazard avoidance on a planetary surface. Finally, we develop and extensively experimentally characterize algorithms for vision-based autonomous landing, object tracking, and sensor deployment.

  11. Visualization of regulations to support design and quality control--a long-term study.

    Science.gov (United States)

    Blomé, Mikael

    2012-01-01

    The aim of the study was to visualize design regulations of furniture by means of interactive technology based on earlier studies and practical examples. The usage of the visualized regulations was evaluated on two occasions: at the start when the first set of regulations was presented, and after six years of usage of all regulations. The visualized regulations were the result of a design process involving experts and potential users in collaboration with IKEA of Sweden AB. The evaluations by the different users showed a very positive response to using visualized regulations. The participative approach, combining expertise in specific regulations with visualization of guidelines, resulted in clear presentations of important regulations, and great attitudes among the users. These kinds of visualizations have proved to be applicable in a variety of product areas at IKEA, with a potential for further dissemination. It is likely that the approaches to design and visualized regulations in this case study could function in other branches.

  12. Estrategia de control para robots manipuladores con realimentación visual y plataforma electro-neumática de 3gdl // Control Scheme for robots manipulators visual servoingand 3DOF electro-pneumatic platform

    Directory of Open Access Journals (Sweden)

    René González-Rodríguez

    2011-08-01

    Full Text Available ResumenEn este artículo se presenta un esquema de control en el espacio de tarea para dos estructuras robóticas diferentes, una plataforma electro-neumática de tres grados de libertad y un sistema servovisual. El esquema de control está basado en la medición del espacio de tarea del sistema. Consta de dos lazos en cascada. En el lazo interno se ejecuta el control articular y en el externo el control en el espacio de tarea. Se presenta el análisis de estabilidad y los resultados experimentales que corroboran el buen funcionamiento del sistema propuesto en un robot manipulador y una plataforma electro-neumática de tres grados de libertad. El esquema presentado abre un nuevo campo de investigación en el área del control en el espacio de tarea para resolver problemas de control de trayectoria y control anticipatorio.Palabras claves: control en el espacio de tarea, control servo visual, robot paralelo__________________________________________________________________________Abstract In this paper a control scheme in the task space is presented for a 3DOF Electro-Pneumatic Platform and Servo-visual System. The control scheme is based on the measurement of system task space state. The control system considers two loops in cascade, an internal loop solving the robot’s joint control and an external loop the task space control. A stability analysis is developed under the conditions that it is possible to approximate the dynamic effect of the internal loop as an external loop time delay. To illustrate the proposed controller, the control system stability and its performance, experimental results using a 3DOF pneumatic parallel robot and servo-visual system are presented. Experimental results confirm the expected step response in the task space. The control scheme presented opens a new research field in the task space control with algorithms for the solution of, trajectory control and feed-forward control.Key words: task space control, visual

  13. Energy Effective Congestion Control for Multicast with Network Coding in Wireless Ad Hoc Network

    Directory of Open Access Journals (Sweden)

    Chuanxin Zhao

    2014-01-01

    Full Text Available In order to improve network throughput and reduce energy consumption, we propose in this paper a cross-layer optimization design that is able to achieve multicast utility maximization and energy consumption minimization. The joint optimization of congestion control and power allocation is formulated to be a nonlinear nonconvex problem. Using dual decomposition, a distributed optimization algorithm is proposed to avoid the congestion by control flow rate at the source node and eliminate the bottleneck by allocating the power at the intermediate node. Simulation results show that the cross-layer algorithm can increase network performance, reduce the energy consumption of wireless nodes and prolong the network lifetime, while keeping network throughput basically unchanged.

  14. Adaptive-Repetitive Visual-Servo Control of Low-Flying Aerial Robots via Uncalibrated High-Flying Cameras

    Science.gov (United States)

    Guo, Dejun; Bourne, Joseph R.; Wang, Hesheng; Yim, Woosoon; Leang, Kam K.

    2017-08-01

    This paper presents the design and implementation of an adaptive-repetitive visual-servo control system for a moving high-flying vehicle (HFV) with an uncalibrated camera to monitor, track, and precisely control the movements of a low-flying vehicle (LFV) or mobile ground robot. Applications of this control strategy include the use of high-flying unmanned aerial vehicles (UAVs) with computer vision for monitoring, controlling, and coordinating the movements of lower altitude agents in areas, for example, where GPS signals may be unreliable or nonexistent. When deployed, a remote operator of the HFV defines the desired trajectory for the LFV in the HFV's camera frame. Due to the circular motion of the HFV, the resulting motion trajectory of the LFV in the image frame can be periodic in time, thus an adaptive-repetitive control system is exploited for regulation and/or trajectory tracking. The adaptive control law is able to handle uncertainties in the camera's intrinsic and extrinsic parameters. The design and stability analysis of the closed-loop control system is presented, where Lyapunov stability is shown. Simulation and experimental results are presented to demonstrate the effectiveness of the method for controlling the movement of a low-flying quadcopter, demonstrating the capabilities of the visual-servo control system for localization (i.e.,, motion capturing) and trajectory tracking control. In fact, results show that the LFV can be commanded to hover in place as well as track a user-defined flower-shaped closed trajectory, while the HFV and camera system circulates above with constant angular velocity. On average, the proposed adaptive-repetitive visual-servo control system reduces the average RMS tracking error by over 77% in the image plane and over 71% in the world frame compared to using just the adaptive visual-servo control law.

  15. Nonparametric Problem-Space Clustering: Learning Efficient Codes for Cognitive Control Tasks

    Directory of Open Access Journals (Sweden)

    Domenico Maisto

    2016-02-01

    Full Text Available We present an information-theoretic method permitting one to find structure in a problem space (here, in a spatial navigation domain and cluster it in ways that are convenient to solve different classes of control problems, which include planning a path to a goal from a known or an unknown location, achieving multiple goals and exploring a novel environment. Our generative nonparametric approach, called the generative embedded Chinese restaurant process (geCRP, extends the family of Chinese restaurant process (CRP models by introducing a parameterizable notion of distance (or kernel between the states to be clustered together. By using different kernels, such as the the conditional probability or joint probability of two states, the same geCRP method clusters the environment in ways that are more sensitive to different control-related information, such as goal, sub-goal and path information. We perform a series of simulations in three scenarios—an open space, a grid world with four rooms and a maze having the same structure as the Hanoi Tower—in order to illustrate the characteristics of the different clusters (obtained using different kernels and their relative benefits for solving planning and control problems.

  16. Energy-Constrained Recharge, Assimilation, and Fractional Crystallization (EC-RAχFC): A Visual Basic computer code for calculating trace element and isotope variations of open-system magmatic systems

    Science.gov (United States)

    Bohrson, Wendy A.; Spera, Frank J.

    2007-11-01

    Volcanic and plutonic rocks provide abundant evidence for complex processes that occur in magma storage and transport systems. The fingerprint of these processes, which include fractional crystallization, assimilation, and magma recharge, is captured in petrologic and geochemical characteristics of suites of cogenetic rocks. Quantitatively evaluating the relative contributions of each process requires integration of mass, species, and energy constraints, applied in a self-consistent way. The energy-constrained model Energy-Constrained Recharge, Assimilation, and Fractional Crystallization (EC-RaχFC) tracks the trace element and isotopic evolution of a magmatic system (melt + solids) undergoing simultaneous fractional crystallization, recharge, and assimilation. Mass, thermal, and compositional (trace element and isotope) output is provided for melt in the magma body, cumulates, enclaves, and anatectic (i.e., country rock) melt. Theory of the EC computational method has been presented by Spera and Bohrson (2001, 2002, 2004), and applications to natural systems have been elucidated by Bohrson and Spera (2001, 2003) and Fowler et al. (2004). The purpose of this contribution is to make the final version of the EC-RAχFC computer code available and to provide instructions for code implementation, description of input and output parameters, and estimates of typical values for some input parameters. A brief discussion highlights measures by which the user may evaluate the quality of the output and also provides some guidelines for implementing nonlinear productivity functions. The EC-RAχFC computer code is written in Visual Basic, the programming language of Excel. The code therefore launches in Excel and is compatible with both PC and MAC platforms. The code is available on the authors' Web sites http://magma.geol.ucsb.edu/and http://www.geology.cwu.edu/ecrafc) as well as in the auxiliary material.

  17. Embedded foveation image coding.

    Science.gov (United States)

    Wang, Z; Bovik, A C

    2001-01-01

    The human visual system (HVS) is highly space-variant in sampling, coding, processing, and understanding. The spatial resolution of the HVS is highest around the point of fixation (foveation point) and decreases rapidly with increasing eccentricity. By taking advantage of this fact, it is possible to remove considerable high-frequency information redundancy from the peripheral regions and still reconstruct a perceptually good quality image. Great success has been obtained previously by a class of embedded wavelet image coding algorithms, such as the embedded zerotree wavelet (EZW) and the set partitioning in hierarchical trees (SPIHT) algorithms. Embedded wavelet coding not only provides very good compression performance, but also has the property that the bitstream can be truncated at any point and still be decoded to recreate a reasonably good quality image. In this paper, we propose an embedded foveation image coding (EFIC) algorithm, which orders the encoded bitstream to optimize foveated visual quality at arbitrary bit-rates. A foveation-based image quality metric, namely, foveated wavelet image quality index (FWQI), plays an important role in the EFIC system. We also developed a modified SPIHT algorithm to improve the coding efficiency. Experiments show that EFIC integrates foveation filtering with foveated image coding and demonstrates very good coding performance and scalability in terms of foveated image quality measurement.

  18. Haptic Addition to a Visual Menu Selection Interface Controlled by an In-Vehicle Rotary Device

    Directory of Open Access Journals (Sweden)

    Camilla Grane

    2012-01-01

    Full Text Available Today, several vehicles are equipped with a visual display combined with a haptic rotary device for handling in-vehicle information system tasks while driving. This experimental study investigates whether a haptic addition to a visual interface interferes with or supports secondary task performance and whether haptic information could be used without taking eyes off road. Four interfaces were compared during simulated driving: visual only, partly corresponding visual-haptic, fully corresponding visual-haptic, and haptic only. Secondary task performance and subjective mental workload were measured. Additionally, the participants were interviewed. It was found that some haptic support improved performance. However, when more haptic information was used, the results diverged in terms of task completion time and interface comprehension. Some participants did not sense all haptics provided, some did not comprehend the correspondence between the haptic and visual interfaces, and some did. Interestingly, the participants managed to complete the tasks when using haptic-only information.

  19. Low back pain status in elite and semi-elite Australian football codes: a cross-sectional survey of football (soccer, Australian rules, rugby league, rugby union and non-athletic controls

    Directory of Open Access Journals (Sweden)

    McHardy Andrew

    2009-04-01

    Full Text Available Abstract Background Our understanding of the effects of football code participation on low back pain (LBP is limited. It is unclear whether LBP is more prevalent in athletic populations or differs between levels of competition. Thus it was the aim of this study to document and compare the prevalence, intensity, quality and frequency of LBP between elite and semi-elite male Australian football code participants and a non-athletic group. Methods A cross-sectional survey of elite and semi-elite male Australian football code participants and a non-athletic group was performed. Participants completed a self-reported questionnaire incorporating the Quadruple Visual Analogue Scale (QVAS and McGill Pain Questionnaire (short form (MPQ-SF, along with additional questions adapted from an Australian epidemiological study. Respondents were 271 elite players (mean age 23.3, range 17–39, 360 semi-elite players (mean age 23.8, range 16–46 and 148 non-athletic controls (mean age 23.9, range 18–39. Results Groups were matched for age (p = 0.42 and experienced the same age of first onset LBP (p = 0.40. A significant linear increase in LBP from the non-athletic group, to the semi-elite and elite groups for the QVAS and the MPQ-SF was evident (p Conclusion Foolers in Australia have significantly more severe and frequent LBP than a non-athletic group and this escalates with level of competition.

  20. Improved EZW image coding algorithm in air traffic control system.%空管系统中运用EZW图像编码算法的优化策略

    Institute of Scientific and Technical Information of China (English)

    胡波; 杨红雨

    2011-01-01

    In order to efficiently transmit the picture data in the air traffic control system, an improved image coding algoRithm, which is based on Embedded Zero-tree Wavelet(EZW),is presented. At fist, the lowest frequency sub-band is coded without loss. Then, based on the human visual system, different sub-bands at the same level based on different perceptual weights are merged. In the end. Huffman coding is used for EZW result. The experiment result shows that this method is better than the original EZW algorithm.%为了在空管系统中高效率传输景象数据,在嵌入式零树小波图像编码算法(EZW)的基础上进行了按步骤的整体优化,对低频子带进行无损编码,对同一级的不同子带根据人眼视觉特性进行加权合并,用Huffman编码对符号流进行二次编码,实验结果表明,该方法要优于传统的EZW算法.