WorldWideScience

Sample records for face significant obstacles

  1. Obstacles Facing the Iranian Basketball Academy

    Directory of Open Access Journals (Sweden)

    Hamta Hadian

    2016-10-01

    Full Text Available This study, which is a strategic study with a mixed research approach aimed to identify obstacles facing the academies of Iranian Basketball Federation. The population comprises board of directors and committees responsible for Education and Talent Spotting Association, academy administrators, physical education instructors, qualified experts, professors, coaches, referees and heads of delegations who were asked via interviews and questionnaire (exploratory manner to state internal and external obstacles facing basketball academies in following 8 components in order of importance utilizing the Delphi method: management and planning, training, human resources, financial resources, talent spotting, scientific and research and information technology, venues and infrastructures. Items were identified in 34 external and 49 internal factors. For weighting and prioritizing of items, the questionnaire was completed by 27 subjects employing AHP method based on pairwise comparisons. SPSS software version18 was utilized for descriptive statistics while AHP method in Expert Choice software was utilized for inferential statistics. At the end, a total of 11 executive strategies were proposed for removing the obstacles.

  2. China Faces Nine Obstacles in Population Development

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    With drastic changes in both the international and domestic environment for population and family planning development, China faces nine major challenges in its efforts to further its population and family planning program, said Zhang Weiqing,Minister of the National Population and Family

  3. Obstacles Facing Promoting Tourism for Islamic Landmarks from the Perspective of Tour Operators in Egypt

    Directory of Open Access Journals (Sweden)

    Suzan Bakri Hassan

    2015-05-01

    Full Text Available The UNESCO launched a campaign #unite4heritage in Egypt to defeat extremism and intolerance. The message of such campaigne is peace, dialogue and unity embedded in cultural heritage. As culture and tourism are linked together, such message could be delivered through improving culture heritage tourism in Egypt. Islamic landmarks  are considered as a part of human heritage. Therefore, the purpose of this study is to identify how much tour operators in Egypt include Islamic landmarks in their programs to determine the obstacles facing promoting cultural tourism in Islamic landmarks' areas. Additionally, the study would identify positive results in the case of developing heritage tourism in Egypt. To achieve a high result, a survey approach was employed to collect data from 100 tour operators, using a completed questionnaire technique as well as a Likert Scale and statistical models in order to test and interpret the research outcomes. The research findings indicated that although tour operators in Egypt are convinced of the significance of the Islamic landmarks, there is no contradiction between creating global understanding and at the same time achieving benefit to the local community. However, there is a range of obstacles facing promoting such type of tourism in Egypt. Keywords: Culture heritage tourism, community, Egypt, Islamic civilization.

  4. Training under Fire: The Relationship between Obstacles Facing Training and SMEs Development in Palestine

    Science.gov (United States)

    AlMadhoun, Mohammed

    2006-01-01

    Purpose: The main objective of this paper is to discuss the relationship between obstacles and weaknesses facing the development of MTPs and SMEs. In recent years many management training programmes (MTPs) of an off-the-job nature have been established in Palestine, after the peace agreement, in order to find a solution for apparent lack of…

  5. Investigation of obstacle effect to improve conjugate heat transfer in backward facing step channel using fast simulation of incompressible flow

    Science.gov (United States)

    Nouri-Borujerdi, Ali; Moazezi, Arash

    2017-07-01

    The current study investigates the conjugate heat transfer characteristics for laminar flow in backward facing step channel. All of the channel walls are insulated except the lower thick wall under a constant temperature. The upper wall includes a insulated obstacle perpendicular to flow direction. The effect of obstacle height and location on the fluid flow and heat transfer are numerically explored for the Reynolds number in the range of 10 ≤ Re ≤ 300. Incompressible Navier-Stokes and thermal energy equations are solved simultaneously in fluid region by the upwind compact finite difference scheme based on flux-difference splitting in conjunction with artificial compressibility method. In the thick wall, the energy equation is obtained by Laplace equation. A multi-block approach is used to perform parallel computing to reduce the CPU time. Each block is modeled separately by sharing boundary conditions with neighbors. The developed program for modeling was written in FORTRAN language with OpenMP API. The obtained results showed that using of the multi-block parallel computing method is a simple robust scheme with high performance and high-order accurate. Moreover, the obtained results demonstrated that the increment of Reynolds number and obstacle height as well as decrement of horizontal distance between the obstacle and the step improve the heat transfer.

  6. Social attributions from faces: determinants, consequences, accuracy, and functional significance.

    Science.gov (United States)

    Todorov, Alexander; Olivola, Christopher Y; Dotsch, Ron; Mende-Siedlecki, Peter

    2015-01-03

    Since the early twentieth century, psychologists have known that there is consensus in attributing social and personality characteristics from facial appearance. Recent studies have shown that surprisingly little time and effort are needed to arrive at this consensus. Here we review recent research on social attributions from faces. Section I outlines data-driven methods capable of identifying the perceptual basis of consensus in social attributions from faces (e.g., What makes a face look threatening?). Section II describes nonperceptual determinants of social attributions (e.g., person knowledge and incidental associations). Section III discusses evidence that attributions from faces predict important social outcomes in diverse domains (e.g., investment decisions and leader selection). In Section IV, we argue that the diagnostic validity of these attributions has been greatly overstated in the literature. In the final section, we offer an account of the functional significance of these attributions.

  7. Obstacles Faced by Heads of Departments and Faculty Members in the Jordanian Public Universities in the Implementation of Vocational and Technical Education Programs from Their Perspective

    Science.gov (United States)

    Hammad, Heba Ibraheem; Airout, Mostafa Mohammad

    2016-01-01

    The purpose of the study is to find out the obstacles faced by heads of departments and faculty members at Jordanian public universities in the implementation of vocational and technical education programs from their perspective, and to find out the effect of gender, experience, and academic rank on their perspective. To achieve the aim of the…

  8. "No Significant Distance" between Face-to-Face and Online Instruction: Evidence from Principles of Economics

    Science.gov (United States)

    Coates, Dennis; Humphreys, Brad, R.; Kane, John; Vachris, Michelle, A.

    2004-01-01

    This paper describes an experiment focused on measuring and explaining differences in students learning between online and face-to-face modes of instruction in college level principles of economics courses. Our results indicate that students in face-to-face sections scored better on the Test of Understanding College Economics (TUCE) than students…

  9. Rerouting end-face-TIR capable rays to significantly increase evanescent wave signal power

    Institute of Scientific and Technical Information of China (English)

    Jianjun Ma; Yasser Chiniforooshan; Huacai Chen; Jiahua Chen; Wojtek J. Bock; Andrea Cusano

    2011-01-01

    The critical findings associated with end-face total internal reflection (TIR) phenomemon we proved before are reported. In particular, these findings reveal that the end-face-TIR capable rays experience enormous mode mixing when encountering a roughened end face. As a result, 94% of the overall detectable power is contributed by this effect. With a smooth fiber end face, this figure is mere 52%. We interpret the mechanism behind these unusual phenomena and its significance for the performance enhancement of fiber optic evanescent wave sensor.%@@ The critical findings associated with end-face total internal reflection (TIR) phenomemon we proved before are reported, In particular, these findings reveal that the end-face-TIR capable rays experience enormous mode mixing when encountering a roughened end face.As a result, 94Vo of the overall detectable poweris contributed by this effect.With a smooth fiber end face, this figure is mere 52%.We interpret the mechanism behind these unusual phenomena and its significance for the performance enhancement of fiber optic evanescent wave sensor.

  10. Recovering an electromagnetic obstacle by a few phaseless backscattering measurements

    Science.gov (United States)

    Li, Jingzhi; Liu, Hongyu; Wang, Yuliang

    2017-03-01

    We consider the electromagnetic scattering from a convex polyhedral PEC or PMC obstacle due to a time-harmonic incident plane wave. It is shown that the modulus of the far-field pattern in the backscattering aperture possesses a certain local maximum behavior. Using the local maximum indicating phenomena, one can determine the exterior unit normal directions, as well as the face areas, of the front faces of the obstacle. Then we propose a recovery scheme of reconstructing the obstacle by phaseless backscattering measurements. This work significantly extends our recent study in Li and Liu (2014 preprint) from two dimensions and acoustic scattering to the more challenging three dimensions and electromagnetic scattering.

  11. Shock Wave Attenuation Using Foam Obstacles: Does Geometry Matter?

    Directory of Open Access Journals (Sweden)

    Hongjoo Jeon

    2015-06-01

    Full Text Available A shock wave impact study on open and closed cell foam obstacles was completed to assess attenuation effects with respect to different front face geometries of the foam obstacles. Five different types of geometries were investigated, while keeping the mass of the foam obstacle constant. The front face, i.e., the side where the incident shock wave impacts, were cut in geometries with one, two, three or four convergent shapes, and the results were compared to a foam block with a flat front face. Results were obtained by pressure sensors located upstream and downstream of the foam obstacle, in addition to high-speed schlieren photography. Results from the experiments show no significant difference between the five geometries, nor the two types of foam.

  12. Ranking fluctuating asymmetry in a dot figure and the significant impact of imagining a face.

    Science.gov (United States)

    Neby, Magne; Ivar, Folstad

    2013-01-01

    Fluctuating asymmetry and averageness is correlated with our perception of beauty in human faces. Yet, whether deviations of centrality in the positioning of the eyes, the nose, and the mouth have different effects on our perception of asymmetry in a holistic human face, is still uncertain. In this study we aimed to test the relative effect of decentralising the horizontal position of three sets of paired dots representing eyes, nostrils, or mouth from the vertical midline of ambiguous dot figures, vaguely resembling a face. The figures were ranked according to perceived asymmetry by human observers. When associating the figures with non-facial objects (eg a butterfly), none of the figures' rank distribution differed from each other. However, when observers imagined the figures to represent a human face, the figure with the decentralised pair of dots representing the nostrils was significantly ranked as more asymmetric than the other figures. This result provides indications that the brain may deal with information about facial asymmetry and averageness heavily depending on the centrality of the nasal region.

  13. A blended learning approach to teaching basic pharmacokinetics and the significance of face-to-face interaction.

    Science.gov (United States)

    Edginton, Andrea; Holbrook, Jane

    2010-06-15

    To assess pharmacy students' attitudes towards a blended-learning pharmacokinetics course. Narrated visual presentations and animations that illustrated kinetic processes and guided students through the use of software programs used for calculations were created. Other learning techniques used included online self-assessment quizzes, practice problem sets, and weekly face-to-face problem-solving tutorials. A precourse questionnaire to assess students' level of enthusiasm towards the blended-learning course and to solicit any concerns they had was administered at the beginning of the course. A postcourse questionnaire that included the same 4 Likert-scale items from the precourse questionnaire and follow-up open-ended questions was administered. Individual changes in level of enthusiasm were compared for individuals who completed both the precourse and postcourse questionnaire. Students' concerns about the blended method of learning had decreased postcourse while their enthusiasm for the benefits of blended learning had increased. Students' initial concerns about the blended learning experience were focused on their ability to communicate with the instructor about the online components, but shifted to their own time management skills at the end of the course. Face-to-face interactions with each other and with the instructor were more highly rated than online interactions in this course.

  14. Attachment Avoidance Is Significantly Related to Attentional Preference for Infant Faces: Evidence from Eye Movement Data

    Science.gov (United States)

    Jia, Yuncheng; Cheng, Gang; Zhang, Dajun; Ta, Na; Xia, Mu; Ding, Fangyuan

    2017-01-01

    Objective: To determine the influence of adult attachment orientations on infant preference. Methods: We adopted eye-tracking technology to monitor childless college women’s eye movements when looking at pairs of faces, including one adult face (man or woman) and one infant face, with three different expressions (happy, sadness, and neutral). The participants (N = 150; 84% Han ethnicity) were aged 18–29 years (M = 19.22, SD = 1.72). A random intercepts multilevel linear regression analysis was used to assess the unique contribution of attachment avoidance, determined using the Experiences in Close Relationships scale, to preference for infant faces. Results: Women with higher attachment avoidance showed less infant preference, as shown by less sustained overt attentional bias to the infant face than the adult face based on fixation time and count. Conclusion: Adult attachment might be related to infant preference according to eye movement indices. Women with higher attachment avoidance may lack attentional preference for infant faces. The findings may aid the treatment and remediation of the interactions between children and mothers with insecure attachment. PMID:28184210

  15. Irregular Time Dependent Obstacles

    CERN Document Server

    Lindqvist, Peter

    2010-01-01

    We study the obstacle problem for the Evolutionary p-Laplace Equation when the obstacle is discontinuous and without regularity in the time variable. Two quite different procedures yield the same solution.

  16. Optimal obstacle control problem

    Institute of Scientific and Technical Information of China (English)

    ZHU Li; LI Xiu-hua; GUO Xing-ming

    2008-01-01

    In the paper we discuss some properties of the state operators of the optimal obstacle control problem for elliptic variational inequality. Existence, uniqueness and regularity of the optimal control problem are established. In addition, the approximation of the optimal obstacle problem is also studied.

  17. DIFFERENTIAL SOIL IMPEDANCE OBSTACLE DETECTION

    Energy Technology Data Exchange (ETDEWEB)

    Maximillian J. Kieba; Christopher J. Ziolkowski

    2004-06-30

    This project develops a new and unique obstacle detection sensor for horizontal directional drilling (HDD) equipment. The development of this new technology will greatly improve the reliability and safety of natural gas HDD construction practices. This sensor utilizes a differential soil impedance measurement technique that will be sensitive to the presence of plastic and ceramic, as well as metallic obstacles. The use of HDD equipment has risen significantly in the gas industry because HDD provides a much more cost-effective and less disruptive method for gas pipe installation than older, trenching methods. However, there have been isolated strikes of underground utilities by HDD equipment, which may have been avoided if methods were available to detect other underground obstacles when using HDD systems. GTI advisors from the gas industry have ranked the value of solving the obstacle detection problem as the most important research and development project for GTI to pursue using Federal Energy Regulatory Commission (FERC) funds available through its industry partner, GRI. GTI proposes to develop a prototype down-hole sensor system that is simple and compact. The sensor utilizes an impedance measurement technique that is sensitive to the presence of metallic or nonmetallic objects in the proximity of the HDD head. The system will use a simple sensor incorporated into the drill head. The impedance of the soil will be measured with a low frequency signal injected through the drill head itself. A pair of bridge type impedance sensors, mounted orthogonal to one another, is coupled to the soil. Inclusions in the soil will cause changes to the sensor balance distinguishable from homogeneous soil. The sensor will provide range and direction data for obstacles near the HDD head. The goal is to provide a simple, robust system that provides the information required to avoid obstacles. This must be done within the size and ruggedness constraints of the HDD equipment. Imaging

  18. DIFFERENTIAL SOIL IMPEDANCE OBSTACLE DETECTION

    Energy Technology Data Exchange (ETDEWEB)

    Maximillian J. Kieba

    2003-10-01

    This project develops a new and unique obstacle detection sensor for horizontal directional drilling (HDD) equipment. The development of this new technology will greatly improve the reliability and safety of natural gas HDD construction practices. This sensor utilizes a differential soil impedance measurement technique that will be sensitive to the presence of plastic and ceramic, as well as metallic obstacles. The use of HDD equipment has risen significantly in the gas industry because HDD provides a much more cost-effective and less disruptive method for gas pipe installation than older, trenching methods. However, there have been isolated strikes of underground utilities by HDD equipment, which may have been avoided if methods were available to detect other underground obstacles when using HDD systems. GTI advisors from the gas industry have ranked the value of solving the obstacle detection problem as the most important research and development project for GTI to pursue using Federal Energy Regulatory Commission (FERC) funds available through its industry partner, GRI. GTI proposes to develop a prototype down-hole sensor system that is simple and compact. The sensor utilizes an impedance measurement technique that is sensitive to the presence of metallic or nonmetallic objects in the proximity of the HDD head. The system will use a simple sensor incorporated into the drill head. The impedance of the soil will be measured with a low frequency signal injected through the drill head itself. A pair of bridge type impedance sensors, mounted orthogonal to one another, is coupled to the soil. Inclusions in the soil will cause changes to the sensor balance distinguishable from homogeneous soil. The sensor will provide range and direction data for obstacles near the HDD head. The goal is to provide a simple, robust system that provides the information required to avoid obstacles. This must be done within the size and ruggedness constraints of the HDD equipment. Imaging

  19. DIFFERENTIAL SOIL IMPEDANCE OBSTACLE DETECTION

    Energy Technology Data Exchange (ETDEWEB)

    Maximillian J. Kieba

    2003-04-01

    This project develops a new and unique obstacle detection sensor for horizontal directional drilling (HDD) equipment. The development of this new technology will greatly improve the reliability and safety of natural gas HDD construction practices. This sensor utilizes a differential soil impedance measurement technique that will be sensitive to the presence of plastic and ceramic, as well as metallic obstacles. The use of HDD equipment has risen significantly in the gas industry because HDD provides a much more cost-effective and less disruptive method for gas pipe installation than older, trenching methods. However, there have been isolated strikes of underground utilities by HDD equipment, which may have been avoided if methods were available to detect other underground obstacles when using HDD systems. GTI advisors from the gas industry have ranked the value of solving the obstacle detection problem as the most important research and development project for GTI to pursue using Federal Energy Regulatory Commission (FERC) funds available through its industry partner, GRI. GTI proposes to develop a prototype down-hole sensor system that is simple and compact. The sensor utilizes an impedance measurement technique that is sensitive to the presence of metallic or nonmetallic objects in the proximity of the HDD head. The system will use a thin film sensor conformal with the drill head. The impedance of the soil will be measured with a low frequency signal injected through the drill head itself. A pair of bridge type impedance sensors, mounted orthogonal to one another, is capacitively coupled to the soil. Inclusions in the soil will cause changes to the sensor balance distinguishable from homogeneous soil. The sensor will provide range and direction data for obstacles near the HDD head. The goal is to provide a simple, robust system that provides the information required to avoid obstacles. This must be done within the size and ruggedness constraints of the HDD

  20. DIFFERENTIAL SOIL IMPEDANCE OBSTACLE DETECTION

    Energy Technology Data Exchange (ETDEWEB)

    Maximillian J. Kieba; Christopher J. Ziolkowski

    2005-01-17

    This project aimed at developing a new and unique obstacle detection sensor for horizontal directional drilling (HDD) equipment. The development of this new technology will greatly improve the reliability and safety of natural gas HDD construction practices. This sensor utilizes a differential soil impedance measurement technique that will be sensitive to the presence of plastic and ceramic, as well as metallic obstacles. The use of HDD equipment has risen significantly in the gas industry because HDD provides a much more cost-effective and less disruptive method for gas pipe installation than older, trenching methods. However, there have been isolated strikes of underground utilities by HDD equipment, which may have been avoided if methods were available to detect other underground obstacles when using HDD systems. GTI advisors from the gas industry ranked the value of solving the obstacle detection problem as the most important research and development project for GTI to pursue using Federal Energy Regulatory Commission (FERC) funds available through its industry partner, GTI. GTI proposed to develop a prototype down-hole sensor system that is simple and compact. The sensor utilizes an impedance measurement technique that is sensitive to the presence of metallic or non-metallic objects in the proximity of the HDD head. The system will use a simple sensor incorporated into the drill head. The impedance of the soil will be measured with a low frequency signal injected through the drill head itself. A pair of bridge type impedance sensors, mounted orthogonal to one another, is coupled to the soil. Inclusions in the soil will cause changes to the sensor balance distinguishable from homogeneous soil. The sensor will provide range and direction data for obstacles near the HDD head. The goal is to provide a simple, robust system that provides the information required to avoid obstacles. This must be done within the size and ruggedness constraints of the HDD equipment

  1. DIFFERENTIAL SOIL IMPEDANCE OBSTACLE DETECTION

    Energy Technology Data Exchange (ETDEWEB)

    Maximillian J. Kieba

    2003-01-30

    This project develops a new and unique obstacle detection sensor for horizontal directional drilling (HDD) equipment. The development of this new technology will greatly improve the reliability and safety of natural gas HDD construction practices. This sensor utilizes a differential soil impedance measurement technique that will be sensitive to the presence of plastic and ceramic, as well as metallic obstacles. The use of HDD equipment has risen significantly in the gas industry because HDD provides a much more cost-effective and less disruptive method for gas pipe installation than older, trenching methods. However, there have been isolated strikes of underground utilities by HDD equipment, which may have been avoided if methods were available to detect other underground obstacles when using HDD systems. GTI advisors from the gas industry have ranked the value of solving the obstacle detection problem as the most important research and development project for GTI to pursue using Federal Energy Regulatory Commission (FERC) funds available through its industry partner, GRI. GTI proposes to develop a prototype down-hole sensor system that is simple and compact. The sensor utilizes an impedance measurement technique that is sensitive to the presence of metallic or nonmetallic objects in the proximity of the HDD head. The system will use a thin film sensor conformal with the drill head. The impedance of the soil will be measured with a low frequency signal injected through the drill head itself. A pair of bridge type impedance sensors, mounted orthogonal to one another, is capacitively coupled to the soil. Inclusions in the soil will cause changes to the sensor balance distinguishable from homogeneous soil. The sensor will provide range and direction data for obstacles near the HDD head. The goal is to provide a simple, robust system that provides the information required to avoid obstacles. This must be done within the size and ruggedness constraints of the HDD

  2. DIFFERENTIAL SOIL IMPEDANCE OBSTACLE DETECTION

    Energy Technology Data Exchange (ETDEWEB)

    Maximillian J. Kieba; Christopher J. Ziolkowski

    2004-10-29

    This project develops a new and unique obstacle detection sensor for horizontal directional drilling (HDD) equipment. The development of this new technology will greatly improve the reliability and safety of natural gas HDD construction practices. This sensor utilizes a differential soil impedance measurement technique that will be sensitive to the presence of plastic and ceramic, as well as metallic obstacles. The use of HDD equipment has risen significantly in the gas industry because HDD provides a much more cost-effective and less disruptive method for gas pipe installation than older, trenching methods. However, there have been isolated strikes of underground utilities by HDD equipment, which may have been avoided if methods were available to detect other underground obstacles when using HDD systems. GTI advisors from the gas industry have ranked the value of solving the obstacle detection problem as the most important research and development project for GTI to pursue using Federal Energy Regulatory Commission (FERC) funds available through its industry partner, GRI. GTI proposes to develop a prototype down-hole sensor system that is simple and compact. The sensor utilizes an impedance measurement technique that is sensitive to the presence of metallic or non-metallic objects in the proximity of the HDD head. The system will use a simple sensor incorporated into the drill head. The impedance of the soil will be measured with a low frequency signal injected through the drill head itself. A pair of bridge type impedance sensors, mounted orthogonal to one another, is coupled to the soil. Inclusions in the soil will cause changes to the sensor balance distinguishable from homogeneous soil. The sensor will provide range and direction data for obstacles near the HDD head. The goal is to provide a simple, robust system that provides the information required to avoid obstacles. This must be done within the size and ruggedness constraints of the HDD equipment. Imaging

  3. DIFFERENTIAL SOIL IMPEDANCE OBSTACLE DETECTION

    Energy Technology Data Exchange (ETDEWEB)

    Maximillian J. Kieba

    2002-08-30

    This project develops a new and unique obstacle detection sensor for horizontal directional drilling (HDD) equipment. The development of this new technology will greatly improve the reliability and safety of natural gas HDD construction practices. This sensor utilizes a differential soil impedance measurement technique that will be sensitive to the presence of plastic and ceramic, as well as metallic obstacles. The use of HDD equipment has risen significantly in the gas industry because HDD provides a much more cost-effective and less disruptive method for gas pipe installation than older, trenching methods. However, there have been isolated strikes of underground utilities by HDD equipment, which may have been avoided if methods were available to detect other underground obstacles when using HDD systems. GTI advisors from the gas industry have ranked the value of solving the obstacle detection problem as the most important research and development project for GTI to pursue using Federal Energy Regulatory Commission (FERC) funds available through its industry partner, GRI. GTI proposes to develop a prototype down-hole sensor system that is simple and compact. The sensor utilizes an impedance measurement technique that is sensitive to the presence of metallic or nonmetallic objects in the proximity of the HDD head. The system will use a thin film sensor conformal with the drill head. The impedance of the soil will be measured with a low frequency signal injected through the drill head itself. A pair of bridge type impedance sensors, mounted orthogonal to one another, is capacitively coupled to the soil. Inclusions in the soil will cause changes to the sensor balance distinguishable from homogeneous soil. The sensor will provide range and direction data for obstacles near the HDD head. The goal is to provide a simple, robust system that provides the information required to avoid obstacles. This must be done within the size and ruggedness constraints of the HDD

  4. DIFFERENTIAL SOIL IMPEDANCE OBSTACLE DETECTION

    Energy Technology Data Exchange (ETDEWEB)

    Maximillian J. Kieba

    2004-02-01

    This project develops a new and unique obstacle detection sensor for horizontal directional drilling (HDD) equipment. The development of this new technology will greatly improve the reliability and safety of natural gas HDD construction practices. This sensor utilizes a differential soil impedance measurement technique that will be sensitive to the presence of plastic and ceramic, as well as metallic obstacles. The use of HDD equipment has risen significantly in the gas industry because HDD provides a much more cost-effective and less disruptive method for gas pipe installation than older, trenching methods. However, there have been isolated strikes of underground utilities by HDD equipment, which may have been avoided if methods were available to detect other underground obstacles when using HDD systems. GTI advisors from the gas industry have ranked the value of solving the obstacle detection problem as the most important research and development project for GTI to pursue using Federal Energy Regulatory Commission (FERC) funds available through its industry partner, GRI. GTI proposes to develop a prototype down-hole sensor system that is simple and compact. The sensor utilizes an impedance measurement technique that is sensitive to the presence of metallic or nonmetallic objects in the proximity of the HDD head. The system will use a simple sensor incorporated into the drill head. The impedance of the soil will be measured with a low frequency signal injected through the drill head itself. A pair of bridge type impedance sensors, mounted orthogonal to one another, is coupled to the soil. Inclusions in the soil will cause changes to the sensor balance distinguishable from homogeneous soil. The sensor will provide range and direction data for obstacles near the HDD head. The goal is to provide a simple, robust system that provides the information required to avoid obstacles. This must be done within the size and ruggedness constraints of the HDD equipment. Imaging

  5. DIFFERENTIAL SOIL IMPEDANCE OBSTACLE DETECTION

    Energy Technology Data Exchange (ETDEWEB)

    Maximillian J. Kieba

    2002-11-27

    This project develops a new and unique obstacle detection sensor for horizontal directional drilling (HDD) equipment. The development of this new technology will greatly improve the reliability and safety of natural gas HDD construction practices. This sensor utilizes a differential soil impedance measurement technique that will be sensitive to the presence of plastic and ceramic, as well as metallic obstacles. The use of HDD equipment has risen significantly in the gas industry because HDD provides a much more cost-effective and less disruptive method for gas pipe installation than older, trenching methods. However, there have been isolated strikes of underground utilities by HDD equipment, which may have been avoided if methods were available to detect other underground obstacles when using HDD systems. GTI advisors from the gas industry have ranked the value of solving the obstacle detection problem as the most important research and development project for GTI to pursue using Federal Energy Regulatory Commission (FERC) funds available through its industry partner, GRI. GTI proposes to develop a prototype down-hole sensor system that is simple and compact. The sensor utilizes an impedance measurement technique that is sensitive to the presence of metallic or nonmetallic objects in the proximity of the HDD head. The system will use a thin film sensor conformal with the drill head. The impedance of the soil will be measured with a low frequency signal injected through the drill head itself. A pair of bridge type impedance sensors, mounted orthogonal to one another, is capacitively coupled to the soil. Inclusions in the soil will cause changes to the sensor balance distinguishable from homogeneous soil. The sensor will provide range and direction data for obstacles near the HDD head. The goal is to provide a simple, robust system that provides the information required to avoid obstacles. This must be done within the size and ruggedness constraints of the HDD

  6. DIFFERENTIAL SOIL IMPEDANCE OBSTACLE DETECTION

    Energy Technology Data Exchange (ETDEWEB)

    Maximillian J. Kieba

    2004-05-03

    This project develops a new and unique obstacle detection sensor for horizontal directional drilling (HDD) equipment. The development of this new technology will greatly improve the reliability and safety of natural gas HDD construction practices. This sensor utilizes a differential soil impedance measurement technique that will be sensitive to the presence of plastic and ceramic, as well as metallic obstacles. The use of HDD equipment has risen significantly in the gas industry because HDD provides a much more cost-effective and less disruptive method for gas pipe installation than older, trenching methods. However, there have been isolated strikes of underground utilities by HDD equipment, which may have been avoided if methods were available to detect other underground obstacles when using HDD systems. GTI advisors from the gas industry have ranked the value of solving the obstacle detection problem as the most important research and development project for GTI to pursue using Federal Energy Regulatory Commission (FERC) funds available through its industry partner, GRI. GTI proposes to develop a prototype down-hole sensor system that is simple and compact. The sensor utilizes an impedance measurement technique that is sensitive to the presence of metallic or nonmetallic objects in the proximity of the HDD head. The system will use a simple sensor incorporated into the drill head. The impedance of the soil will be measured with a low frequency signal injected through the drill head itself. A pair of bridge type impedance sensors, mounted orthogonal to one another, is coupled to the soil. Inclusions in the soil will cause changes to the sensor balance distinguishable from homogeneous soil. The sensor will provide range and direction data for obstacles near the HDD head. The goal is to provide a simple, robust system that provides the information required to avoid obstacles. This must be done within the size and ruggedness constraints of the HDD equipment. Imaging

  7. Obstacles to Laser Safety

    Energy Technology Data Exchange (ETDEWEB)

    Barat, K

    2005-04-25

    The growth of laser development & technology has been remarkable. Unfortunately, a number of traps or obstacles to laser safety have also developed with that growth. The goal of this article is to highlight those traps, in the hope that an aware laser user will avoid them. These traps have been the cause or contributing factor of many a preventable laser accident.

  8. CLINICAL WASTE HANDLING AND OBSTACLES IN MALAYSIA

    Directory of Open Access Journals (Sweden)

    Shaidatul Shida Razali

    2010-12-01

    Full Text Available As in many other developing countries, the generation of clinical waste in Malaysia has increased significantly over the last few decades. Even though the serious impact of the clinical waste on human beings and the environment is significant, only minor attention is directed to its proper handling and legal aspects. This study seeks to examine the management of clinical waste in Selangor’s government hospitals as well as problems that arise from the current practice of clinical waste management. A depth interview with the responsible concession who handles the clinical waste management in those hospitals also has been taken. In general, it was found that the consortium’s administration was reasonably aware of the importance of clinical waste management. However, significant voids were presented that need to be addressed in future including efficient segregation, better handling and transfer means, as well as the need for training and awareness programs for the personnel. Other obstacles faced by consortiums were to handle the clinical waste including the operational costs. Waste minimizing and recycling, as well as the alternative treatment methods for incineration are regarded to be major challenges in the future.

  9. Urbanization of rural migrant workers in China are facing the system obstacle and countermeasures of analysis%我国农民工市民化所面临的制度障碍及对策分析

    Institute of Scientific and Technical Information of China (English)

    轩燕娜

    2014-01-01

    Along with the our country city urbanization process accelerating, more and more surplus rural labor pouring into the city, in order to seek work and life chances. This large groups of migrant workers contribute to the city development, is facing the whole from the household registration system and the closely related to employment, education and social security alliance and so on a series of institutional exclusion. Therefore, how to get a clear understanding and analysis of the current institutional barriers and effectively increase the system supply, in order to find the urbanization of peasant workers out of the way, having important significance for the development of China's industrialization, urbanization and modernization comprehensive.%随着我国城市化进程的不断加快,越来越多的农村剩余劳动力涌入城市,以寻求工作和生活的机会。这一庞大的农民工群体为城市发展做出贡献的同时,自身却面临着来自户籍制度以及与之密切相关联的就业、教育和社会保障等一系列制度的整体排斥。因此,如何清醒地认识和分析现行制度上的障碍并有效地增加制度供给,从而找到农民工市民化的出路,对全面推进我国工业化、城市化和现代化事业的发展有着积极的意义和作用。

  10. 基于视觉显著性的人脸文字区域提取%Regional Extraction of Human Faces and Text Based on Visual Significant

    Institute of Scientific and Technical Information of China (English)

    何贵阳

    2014-01-01

    Based on the Matlab image text region detection method,a new method combining graphic separation and signifi-cant operation was proposed.Further significant fusion about traditional face text area detection results was realized based on visual significant face text region extraction demonstration system.The experimental results show that the proposed solution has higher recall ratio and precision.%基于Matlab 图像文字区域检测新方法对图文进行分离和显著性操作,并采用显著性度量对传统人脸文字区域检测的结果做进一步的显著性融合,实现了基于视觉显著性的人脸文字区域提取。实验结果表明,这种基于视觉显著性的人脸文字区域提取解决方案具有比较高的查全率和精确度。

  11. "Differences" are the Biggest Obstacle

    Institute of Scientific and Technical Information of China (English)

    常胜越

    2008-01-01

    China has the greatest numbers of both teachers and students worldwide ,who teach and learn English. Therefore ,to analyze the obstacles of learning English for Chinese is necessary. This article gives the idea of differences between Chinese and English mainly in languages and cultures fields. Through these we can see deafly that "differences" are the biggest obstacle in language learning.

  12. Famous face recognition, face matching, and extraversion.

    Science.gov (United States)

    Lander, Karen; Poyarekar, Siddhi

    2015-01-01

    It has been previously established that extraverts who are skilled at interpersonal interaction perform significantly better than introverts on a face-specific recognition memory task. In our experiment we further investigate the relationship between extraversion and face recognition, focusing on famous face recognition and face matching. Results indicate that more extraverted individuals perform significantly better on an upright famous face recognition task and show significantly larger face inversion effects. However, our results did not find an effect of extraversion on face matching or inverted famous face recognition.

  13. Optimal Obstacle Placement with Disambiguations.

    OpenAIRE

    Ceyhan, Elvan; Aksakalli, Vural

    2012-01-01

    arXiv:1201.5076v3 [stat.AP] 14 Jan 2013 The Annals of Applied Statistics 2012, Vol. 6, No. 4, 1730–1774 DOI: 10.1214/12-AOAS556 c Institute of Mathematical Statistics, 2012 OPTIMAL OBSTACLE PLACEMENT WITH DISAMBIGUATIONS By Vural Aksakalli and Elvan Ceyhan Istanbul S¸ehir University and Ko¸c University We introduce the optimal obstacle placement with disambigua-tions problem wherein the goal is to place true obstacles in an en-vironment cluttered with false obst...

  14. Obstacles to Scientific Research in Light of a Number of Variables

    Science.gov (United States)

    Algadheeb, Nourah A.; Almeqren, Monira A.

    2014-01-01

    The present study aimed to identify the scientific research obstacles facing faculty members in the College of Education at Princess Nora bint Abdul Rahman University (PNU) and to determine the differences in the obstacles according to age, academic rank, scientific specialty, marital status, number of completed studies, and time since the last…

  15. Obstacles to Scientific Research in Light of a Number of Variables

    Science.gov (United States)

    Algadheeb, Nourah A.; Almeqren, Monira A.

    2014-01-01

    The present study aimed to identify the scientific research obstacles facing faculty members in the College of Education at Princess Nora bint Abdul Rahman University (PNU) and to determine the differences in the obstacles according to age, academic rank, scientific specialty, marital status, number of completed studies, and time since the last…

  16. The Study of Cooperative Obstacle Avoidance Method for MWSN Based on Flocking Control

    Directory of Open Access Journals (Sweden)

    Zuo Chen

    2014-01-01

    Full Text Available Compared with the space fixed feature of traditional wireless sensor network (WSN, mobile WSN has better robustness and adaptability in unknown environment, so that it is always applied in the research of target tracking. In order to reach the target, the nodes group should find a self-adaptive method to avoid the obstacles together in their moving directions. Previous methods, which were based on flocking control model, realized the strategy of obstacle avoidance by means of potential field. However, these may sometimes lead the nodes group to fall into a restricted area like a trap and never get out of it. Based on traditional flocking control model, this paper introduced a new cooperative obstacle avoidance model combined with improved SA obstacle avoidance algorithm. It defined the tangent line of the intersection of node’s velocity line and the edge of obstacle as the steering direction. Furthermore, the cooperative obstacle avoidance model was also improved in avoiding complex obstacles. When nodes group encounters mobile obstacles, nodes will predict movement path based on the spatial location and velocity of obstacle. And when nodes group enters concave obstacles, nodes will temporarily ignore the gravity of the target and search path along the edge of the concave obstacles. Simulation results showed that cooperative obstacle avoidance model has significant improvement on average speed and time efficiency in avoiding obstacle compared with the traditional flocking control model. It is more suitable for obstacle avoidance in complex environment.

  17. Robot Avoids Collisions With Obstacles

    Science.gov (United States)

    Cheung, Edward; Rosinski, Doug; Wegerif, Dan

    1993-01-01

    Developmental robot equipped with infrared sensors and control system acting in concert to enable manipulator arm to move around obstacles. Robot avoids collisions with other objects, even when moving in unpredictable ways. Control system requires no prior knowledge of environment.

  18. Obstacle problems in mathematical physics

    CERN Document Server

    Rodrigues, J-F

    1987-01-01

    The aim of this research monograph is to present a general account of the applicability of elliptic variational inequalities to the important class of free boundary problems of obstacle type from a unifying point of view of classical Mathematical Physics.The first part of the volume introduces some obstacle type problems which can be reduced to variational inequalities. Part II presents some of the main aspects of the theory of elliptic variational inequalities, from the abstract hilbertian framework to the smoothness of the variational solution, discussing in general the properties of the free boundary and including some results on the obstacle Plateau problem. The last part examines the application to free boundary problems, namely the lubrication-cavitation problem, the elastoplastic problem, the Signorini (or the boundary obstacle) problem, the dam problem, the continuous casting problem, the electrochemical machining problem and the problem of the flow with wake in a channel past a profile.

  19. Gunshot wounds and blast injuries to the face are associated with significant morbidity and mortality: results of an 11-year multi-institutional study of 720 patients.

    Science.gov (United States)

    Shackford, Steven R; Kahl, Jessica E; Calvo, Richard Y; Kozar, Rosemary A; Haugen, Christine E; Kaups, Krista L; Willey, Marybeth; Tibbs, Brian M; Mutto, Susan M; Rizzo, Anne G; Lormel, Christy S; Shackford, Meghan C; Burlew, Clay Cothren; Moore, Ernest E; Cogbill, Thomas H; Kallies, Kara J; Haan, James M; Ward, Jeanette

    2014-02-01

    Gunshot wounds and blast injuries to the face (GSWBIFs) produce complex wounds requiring management by multiple surgical specialties. Previous work is limited to single institution reports with little information on processes of care or outcome. We sought to determine those factors associated with hospital complications and mortality. We performed an 11-year multicenter retrospective cohort analysis of patients sustaining GSWBIF. The face, defined as the area anterior to the external auditory meatuses from the top of the forehead to the chin, was categorized into three zones: I, the chin to the base of the nose; II, the base of the nose to the eyebrows; III, above the brows. We analyzed the effect of multiple factors on outcome. From January 1, 2000, to December 31, 2010, we treated 720 patients with GSWBIF (539 males, 75%), with a median age of 29 years. The wounding agent was handgun in 41%, explosive (shotgun and blast) in 20%, rifle in 6%, and unknown in 33%. Prehospital or resuscitative phase airway was required in 236 patients (33%). Definitive care was rendered by multiple specialties in 271 patients (38%). Overall, 185 patients died (26%), 146 (79%) within 48 hours. Of the 481 patients hospitalized greater than 48 hours, 184 had at least one complication (38%). Factors significantly associated with any of a total of 207 complications were total number of operations (p < 0.001), Revised Trauma Score (RTS, p < 0.001), and head Abbreviated Injury Scale (AIS) score (p < 0.05). Factors significantly associated with mortality were RTS (p < 0.001), head AIS score (p < 0.001), total number of operations (p < 0.001), and age (p < 0.05). An injury located in Zone III was independently associated with mortality (p < 0.001). GSWBIFs have high mortality and are associated with significant morbidity. The multispecialty involvement required for definitive care necessitates triage to a trauma center and underscores the need for an organized approach and the development of

  20. Mapping Teacher-Faces

    Science.gov (United States)

    Thompson, Greg; Cook, Ian

    2013-01-01

    This paper uses Deleuze and Guattari's concept of faciality to analyse the teacher's face. According to Deleuze and Guattari, the teacher-face is a special type of face because it is an "overcoded" face produced in specific landscapes. This paper suggests four limit-faces for teacher faciality that actualise different mixes of significance and…

  1. Surface obstacles in pulsatile flow

    Science.gov (United States)

    Carr, Ian A.; Plesniak, Michael W.

    2016-11-01

    Flows past obstacles mounted on flat surfaces have been widely studied due to their ubiquity in nature and engineering. For nearly all of these studies, the freestream flow over the obstacle was steady, i.e. constant velocity unidirectional flow. Unsteady, pulsatile flows occur frequently in biology, geophysics, biomedical engineering, etc. Our study is aimed at extending the comprehensive knowledge base that exists for steady flows to considerably more complex pulsatile flows. Beyond the important practical applications, characterizing the vortex and wake dynamics of flows around surface obstacles embedded in pulsatile flows can provide insights into the underlying physics in all wake and junction flows. In this study, we experimentally investigated the wake of four canonical surface obstacles: hemisphere, cube, and circular cylinders with aspect ratio of 1:1 and 2:1. Phase-averaged PIV and hot-wire anemometry are used to characterize the dynamics of coherent structures in the wake and at the windward junction of the obstacles. Complex physics occur during the deceleration phase of the pulsatile inflow. We propose a framework for understanding these physics based on self-induced vortex propagation, similar to the phenomena exhibited by vortex rings. This material is based in part upon work supported by the National Science Foundation under Grant Number CBET-1236351, and GW Centeor Biomimetics and Bioinspired Engineering (COBRE).

  2. Obstacles to and motivation for successful breast-feeding

    Directory of Open Access Journals (Sweden)

    A-M Bergh

    1993-05-01

    Full Text Available This study determined obstetric physiotherapists' perceptions about major obstacles to and methods of motivation for successful breast-feeding by means of the Friedman non-parametric procedure for the two-way analysis of variance. Three categories of obstacles were identified: maternal obstacles, health professionals and society. Maternal obstacles mentioned most were insufficient motivation (25% and knowledge (24%, anxiety (14%, fatigue (14%, and employment (14%. Obstacles related to health professionals included tack of support for mothers (20%, inappropriate lactation management (19%, lack of knowledge (15%, negative attitudes (5% and staff shortages (5%. With regard to society, lack of support (27% and life-styles (29% were identified as significant obstacles. The two most significantly important methods of motivation were information and education (53% and contact with other breast-feeders (27%. It is concluded that breast-feeding education efforts can be improved by identifying obstacles to breast-feeding and methods of motivation and that the Friedman test may be a statistical procedure to consider for determining priorities.

  3. 國家課程與教學推動網絡的困境與想像:以地方國教輔導團為例 The Obstacles Facing the National Curriculum and Instruction Promotion Network and Its Future: Using Local Compulsory Education Advisory Groups as Examples

    Directory of Open Access Journals (Sweden)

    黃騰 Temg Huang

    2010-12-01

    Full Text Available 本研究以縣市層級的「國民教育輔導團」為對象,訪談了四個分布於北、中、南、東縣市的相關行政人員、輔導團員及相關人員。結果發現,目前國家課程與教學的推動面臨四大困境:一、缺乏完善的「行政」與「課程與教學」間的分工與對話機制;二、缺乏課程與教學政策的整合與轉化機制;三、偏重領域學科教學,忽略課程意識的發展;四、對學校層級的課程與教學影響有限。面對此四大 困境,我們建議或許應超越過去「輔導團」為主的課程與教學推動模式,而重新想像一套未來可能的「國家課程與教學推動網絡」。 This study focused on the “Compulsory Education Advisory Groups” at county and city levels, and thereof interviewed administrative staffs, members of the advisory group, and related personnel in the counties and cities of northern, central, southern, and eastern Taiwan. Results showed that, the four obstacles currently facing the National Curriculum and Instruction Promotion Network are: 1 lack of complete division of labor and conversation mechanism between “administration” and “curriculum and instruction” members; 2 lack of integration and transformation mechanism between curriculum and instruction policies; 3 partial emphasis on subject teaching, while neglecting the development of course consciousness; 4 limited influence on curriculum and instruction at the school level. To overcome those four obstacles, this study suggests that the curriculum and teaching promotion model which focuses on the “advisory groups” should be replaced by a new “National Curriculum and Instruction Promotion Network.”

  4. Research on UAV Intelligent Obstacle Avoidance Technology During Inspection of Transmission Line

    Science.gov (United States)

    Wei, Chuanhu; Zhang, Fei; Yin, Chaoyuan; Liu, Yue; Liu, Liang; Li, Zongyu; Wang, Wanguo

    Autonomous obstacle avoidance of unmanned aerial vehicle (hereinafter referred to as UAV) in electric power line inspection process has important significance for operation safety and economy for UAV intelligent inspection system of transmission line as main content of UAV intelligent inspection system on transmission line. In the paper, principles of UAV inspection obstacle avoidance technology of transmission line are introduced. UAV inspection obstacle avoidance technology based on particle swarm global optimization algorithm is proposed after common obstacle avoidance technologies are studied. Stimulation comparison is implemented with traditional UAV inspection obstacle avoidance technology which adopts artificial potential field method. Results show that UAV inspection strategy of particle swarm optimization algorithm, adopted in the paper, is prominently better than UAV inspection strategy of artificial potential field method in the aspects of obstacle avoidance effect and the ability of returning to preset inspection track after passing through the obstacle. An effective method is provided for UAV inspection obstacle avoidance of transmission line.

  5. Mathematical Models of Smart Obstacles

    Science.gov (United States)

    2006-10-01

    Matematica “G. Castelnuovo” Università di Roma “La Sapienza”, Piazzale Aldo Moro 2 00185 Roma Italy Ph. N. +39-06-49913282, FAX N. +39-06...Dipartimento di Matematica G. Castelnuovo Università di Roma La Sapienza, Piazzale Aldo Moro 2 00185 Roma Italy 8. PERFORMING ORGANIZATION REPORT NUMBER 9... Matematica G. Castelnuovo Università di Roma “La Sapienza” 00185 Roma, Italy 2 Smart (or active) obstacles are obstacles that when illuminated by an

  6. Application of Optical Flow Sensors for Dead Reckoning, Heading Reference, Obstacle Detection, and Obstacle Avoidance

    Science.gov (United States)

    2015-09-01

    OPTICAL FLOW SENSORS FOR DEAD RECKONING, HEADING REFERENCE, OBSTACLE DETECTION, AND OBSTACLE AVOIDANCE by Tarek M. Nejah September 2015... SENSORS FOR DEAD RECKONING, HEADING REFERENCE, OBSTACLE DETECTION, AND OBSTACLE AVOIDANCE 5. FUNDING NUMBERS 6. AUTHOR(S) Nejah, Tarek M. 7...avoidance using only one optical mouse sensor was presented in this thesis. Odometry, position tracking, and obstacle avoidance are important issues in

  7. Face-to-face: Perceived personal relevance amplifies face processing.

    Science.gov (United States)

    Bublatzky, Florian; Pittig, Andre; Schupp, Harald T; Alpers, Georg W

    2017-05-01

    The human face conveys emotional and social information, but it is not well understood how these two aspects influence face perception. In order to model a group situation, two faces displaying happy, neutral or angry expressions were presented. Importantly, faces were either facing the observer, or they were presented in profile view directed towards, or looking away from each other. In Experiment 1 (n = 64), face pairs were rated regarding perceived relevance, wish-to-interact, and displayed interactivity, as well as valence and arousal. All variables revealed main effects of facial expression (emotional > neutral), face orientation (facing observer > towards > away) and interactions showed that evaluation of emotional faces strongly varies with their orientation. Experiment 2 (n = 33) examined the temporal dynamics of perceptual-attentional processing of these face constellations with event-related potentials. Processing of emotional and neutral faces differed significantly in N170 amplitudes, early posterior negativity (EPN), and sustained positive potentials. Importantly, selective emotional face processing varied as a function of face orientation, indicating early emotion-specific (N170, EPN) and late threat-specific effects (LPP, sustained positivity). Taken together, perceived personal relevance to the observer-conveyed by facial expression and face direction-amplifies emotional face processing within triadic group situations. © The Author (2017). Published by Oxford University Press.

  8. A Framework for Obstacles Avoidance of Humanoid Robot Using Stereo Vision

    Directory of Open Access Journals (Sweden)

    Widodo Budiharto

    2013-04-01

    Full Text Available In this paper, we propose a framework for multiple moving obstacles avoidance strategy using stereo vision for humanoid robot in indoor environment. We assume that this model of humanoid robot is used as a service robot to deliver a cup to customer from starting point to destination point. We have successfully developed and introduced three main modules to recognize faces, to identify multiple moving obstacles and to initiate a maneuver. A group of people who are walking will be tracked as multiple moving obstacles. Predefined maneuver to avoid obstacles is applied to robot because the limitation of view angle from stereo camera to detect multiple obstacles. The contribution of this research is a new method for multiple moving obstacles avoidance strategy with Bayesian approach using stereo vision based on the direction and speed of obstacles. Depth estimation is used to obtain distance calculation between obstacles and the robot. We present the results of the experiment of the humanoid robot called Gatotkoco II which is used our proposed method and evaluate its performance. The proposed moving obstacles avoidance strategy was tested empirically and proved effective for humanoid robot.

  9. A Framework for Obstacles Avoidance of Humanoid Robot using Stereo Vision

    Directory of Open Access Journals (Sweden)

    Widodo Budiharto

    2013-04-01

    Full Text Available In this paper, we propose a framework for multiple moving obstacles avoidance strategy using stereo vision for humanoid robot in indoor environment. We assume that this model of humanoid robot is used as a service robot to deliver a cup to customer from starting point to destination point. We have successfully developed and introduced three main modules to recognize faces, to identify multiple moving obstacles and to initiate a maneuver. A group of people who are walking will be tracked as multiple moving obstacles. Predefined maneuver to avoid obstacles is applied to robot because the limitation of view angle from stereo camera to detect multiple obstacles. The contribution of this research is a new method for multiple moving obstacles avoidance strategy with Bayesian approach using stereo vision based on the direction and speed of obstacles. Depth estimation is used to obtain distance calculation between obstacles and the robot. We present the results of the experiment of the humanoid robot called Gatotkoco II which is used our proposed method and evaluate its performance. The proposed moving obstacles avoidance strategy was tested empirically and proved effective for humanoid robot.

  10. Internal and External Obstacles to the Development of SMEs in Bosnia and Herzegovina

    Directory of Open Access Journals (Sweden)

    Zijad Džafić

    2011-04-01

    Full Text Available This article describes the small and medium enterprise (SME sectors in Bosnia and Herzegovina (BiH and other Western Balkan countries, and compares their development. The authors identify the levels of development achieved, remedial measures and activities for stimulating this sector. There is special emphasis on external and internal obstacles to small and medium-sized manufacturing enterprises in BiH. The authors conclude that in respect to SMEs BiH lags behind other countries in the region, where this sector has achieved dynamic development and a majority share in the employment market, exports and GDP. That said, there remains a need across the whole region to resolve obstacles in the domestic market, alongside initiating intensive activities aimed at introducing the SMEs to the Single European Market. For BiH, primary research has been carried out to determine the external and internal obstacles to SMEs in the country’s manufacturing sector. The key obstacles are identified, their intensity and grade determined, and they are classified into three groups. Factor analysis was used in determining six factors explaining external obstacles and two factors for internal obstacles. It has also been confirmed that other companies apart from manufacturing SMEs face broadly similar external obstacles, and that these obstacles are more in evidence when compared to the situation in other Western Balkan countries. Recommendations are offered to the Government of BiH and SME managements for removing the obstacles which have been identified.

  11. Obstacle crossing in lower limb amputees

    NARCIS (Netherlands)

    Vrieling, A.H.; van Keeken, H.G.; Schoppen, Tanneke; Otten, Egbert; Halbertsma, J.P.; Hof, A.L.; Postema, K.

    2007-01-01

    Objective: To study limitations in function and adjustment strategies in lower limb amputees during obstacle crossing. Design: Observational cohort study. Subjects: Transfemoral and transtibial amputees and able-bodied control subjects. Methods: In a motion analysis laboratory unimpeded and obstacle

  12. 障碍物对排风柜性能影响的实验研究%Experiment Research of Effect of Obstacles on Performance of Fume Hood

    Institute of Scientific and Technical Information of China (English)

    程勇; 刘东; 李强民

    2011-01-01

    Use experiment method to research the effect of different obstacles and dummy, according to the face velocity distribution of fume hood and fluctuation of velocities of measure points. The results show that small scale obstacle 1 and obstacle 2 located in fume hood have little effects on the performance of fume hood; however, large scale obstacle 3 and standing dummy have added the non-uniformity of face velocity distribution, and the performance of fume hood has obviously became worse. The results have provided some significant suggestions for fume hood operation.%从排风柜面风速分布,测点风速波动等角度出发,采用实验方法研究了柜内不同大小障碍物和站立假人对排风柜性能的影响。实验结果表明:柜内放置面积率较小障碍物1和障碍物2对排风柜性能影响很小;而障碍物3和站立假人使操作口面风速分布明显不均匀,恶化了排风柜的性能;为排风柜的运行管理提供了一定的指导。

  13. Detection And Avoidance Of Obstacles By Helicopters

    Science.gov (United States)

    Cheng, Victor H. L.; Sridhar, Banavar

    1992-01-01

    Report discusses problems relevant to control subsystems enabling helicopters on nap-of-the-Earth flight paths to detect and avoid obstacles automatically. Indicates similarities between this and obstacle-avoidance problem of industrial mobile robots. Two approaches extend two-dimensional obstacle-avoidance concept to three dimensions. First involves direct search of three-dimensional range-map data for indications of openings between obstacles. Second involves compression of data into two-dimensional map for path search.

  14. Obstacles and Drivers in Steering IBS towards Green and Sustainability

    Directory of Open Access Journals (Sweden)

    Seyed Meysam Khoshnava

    2014-10-01

    Full Text Available The aim of this study is investigating IBS potential solution for achieving its prospective in the area of green construction and sustainability. Malaysia has embarked on initiatives for sustainable development consistent with global concerns on the environment and sustaining the world resources for the future generations. The issues of sustainability and green construction have been duly highlighted in the Construction Industry Master Plan (2005-2015 as being of significant importance for the Malaysian construction industry. In this regard, industrialized construction has the unique characteristics to respond well to the sustainability challenge facing the construction industry. Industrialized construction assist adopters in term of cost and time certainty, attaining better construction quality and productivity, reducing risk related to occupational safety and health. But, despite all those capabilities most of the construction work in Malaysia is still applying conventional methods which are not often sustainable. Thus, this study tries to explore obstacles and drivers in steering IBS towards the agenda of green and sustainability.

  15. An Analytical Approach to Avoid Obstacles in Mobile Robot Navigation

    Directory of Open Access Journals (Sweden)

    Alexandre Santos Brandão

    2013-06-01

    Full Text Available A nonlinear supervised globally stable controller is proposed to reactively guide a mobile robot to avoid obstacles while seeking a goal. Whenever the robot detects an object nearby, its orientation is changed to be aligned with the tangent to the border of the obstacle. Then, the robot starts following it, looking for a feasible path to its goal. The supervisor is responsible for deciding which path to take when the robot faces some particular obstacle configurations that are quite difficult to deal with. Several simulations and experiments were run to validate the proposal, some of which are discussed here. To run the experiments, the proposed controller is programmed into the onboard computer of a real unicycle mobile platform, equipped with a laser range scanner. As for the simulations, the models of the same experimental setup were used. The final conclusion is that the nonlinear supervised controller proposed to solve the problem of avoiding obstacles during goal seeking has been validated, based on the theoretical analysis, and the simulated and experimental results.

  16. Neuroepigenomics: resources, obstacles, and opportunities

    Directory of Open Access Journals (Sweden)

    John S. Satterlee

    2015-01-01

    Full Text Available Long-lived postmitotic cells, such as most human neurons, must respond effectively to ongoing changes in neuronal stimulation or microenvironmental cues through transcriptional and epigenomic regulation of gene expression. The role of epigenomic regulation in neuronal function is of fundamental interest to the neuroscience community, as these types of studies have transformed our understanding of gene regulation in postmitotic cells. This perspective article highlights many of the resources available to researchers interested in neuroepigenomic investigations and discusses some of the current obstacles and opportunities in neuroepigenomics.

  17. Relationship between the obstacle height cognition and step movement in the elderly

    Directory of Open Access Journals (Sweden)

    Shin Sohee

    2012-10-01

    Full Text Available Abstract Background This study examines the effect of obstacle height cognition (OHC on single-leg forward step (SFS and Obstacle-SFS. Methods In the SFS test, participants stepped 25 cm forward with one leg and returned it to its original position five times as quickly as possible. The Obstacle-SFS added an obstacle to the above condition in the SFS test. The participants were divided into two groups: tripping group, which tripped over an obstacle in the Obstacle-SFS test; and non-tripping group, which did not trip. Parameters were step time (T, the time it took to step forward (F, and the time it took to return to the original position (R. The OHC was determined by the difference between the elevated leg’s height and the obstacle height (10 cm, which was set at 60 cm in front of the participant. Results OHC showed a significant and moderate relationship with all parameters of Obstacle-SFS (OSFS-T, OSFS-F and OSFS-R. The tripping group had significantly larger values in the OHC, OSFS-T and OSFS-F than the non-tripping group. Conclusions In conclusion, the differences in obstacle height cognition ability may affect Obstacle-SFS movement.

  18. Reciprocally-Rotating Velocity Obstacles

    KAUST Repository

    Giese, Andrew

    2014-05-01

    © 2014 IEEE. Modern multi-agent systems frequently use highlevel planners to extract basic paths for agents, and then rely on local collision avoidance to ensure that the agents reach their destinations without colliding with one another or dynamic obstacles. One state-of-the-art local collision avoidance technique is Optimal Reciprocal Collision Avoidance (ORCA). Despite being fast and efficient for circular-shaped agents, ORCA may deadlock when polygonal shapes are used. To address this shortcoming, we introduce Reciprocally-Rotating Velocity Obstacles (RRVO). RRVO generalizes ORCA by introducing a notion of rotation for polygonally-shaped agents. This generalization permits more realistic motion than ORCA and does not suffer from as much deadlock. In this paper, we present the theory of RRVO and show empirically that it does not suffer from the deadlock issue ORCA has, permits agents to reach goals faster, and has a comparable collision rate at the cost of performance overhead quadratic in the (typically small) user-defined parameter δ.

  19. Cam Tavan Sendromu ve Kadınların Üst Düzey Yönetici Pozisyonuna Yükselmelerindeki Engeller: Balıkesir İli Örneği(Glass Ceiling Syndrome and the Obstacles Facing Women’s Advancement to Senior Management Positions: Evidence From Balikesir

    Directory of Open Access Journals (Sweden)

    Edip ÖRÜCÜ

    2007-01-01

    Full Text Available Examining the reasons why women’s presentation in senior management levels and strategically important positions is lower compared to men constitutes the aim of this study. Conducting a literature survey, the concept of “Glass Ceiling” has been explained and the obstacles confronting women in preferment to senior management positions have been presented depending on the related studies held in Turkey and other countries. In the application part of the study, under the light of the findings from the literature, a survey covering 200 employees, of whom 103 male and 97 female, has been conducted in order to find out about the opinions of employees in Balıkesir on the obstacles in question. The findings have revealed that the limited horizon of leadership and managerial capability, excessive familial responsibilities, and the “queen bee” syndrome are the main obstacles that hamper women in the progress towards senior level managerial positions.

  20. CONCERT MANAGEMENT IN CROATIA: OBSTACLES AND CHALLENGES

    Directory of Open Access Journals (Sweden)

    Irina Basara

    2016-12-01

    Full Text Available The concept of concert management in the Republic of Croatia encounters numerous obstacles in any attempt to institutionalize it. Unlike other countries in the European Union, there is no register of the concert stages, venues as well as facilities for the provision of hearing / consumption of music in the form of performances. Process management organization is incomplete, and institutions that are closely associated with such events do not carry out the classification, categorization and analysis of events that are within the concerts' domain. Commercial music, economically far most cost-effective, is completely ignored and within the framework of cultural events not even the slightest attention is given to it. On the contrary, it is considered the music of poor quality and completely irrelevant. This paper tries to frame the mentioned genre, which includes various musical directions that economically bring significant benefits and help the survival of these related activities indirectly, and ultimately have a positive impact on the economy. Comparing global trends it speaks about the position of the Croatian music industry and lists the main obstacles for setting up a solid foundation for the construction of an adequate system of indexation of concert businesses that, as part of the creative industries records a meteoric economic growth.

  1. How does a cyclist avoid obstacles?

    Science.gov (United States)

    Miyadait, Masayuki; Uetake, Teruo; Shimoda, Masahiro

    2012-12-01

    The purpose of this research is to examine the ways bicycles swerve off sidewalks onto roads under various conditions. Seven students, five males and two females participated in an experiment on a road with a 100-cm wide sidewalk. Footage of each participant on a bicycle evading obstacles such as a utility pole and pedestrian were taken with a video camera, while a front-wheel view of the path taken by the bicycle was recorded simultaneously with a digital camera. Twelve experimental conditions were used for each participant, consisting of all the combinations of (1) three obstacle types, (2) the side (left or right) to which the bicycle went to avoid the obstacle, and (3) two weather conditions. Based on the two recorded scenes, the path was then analyzed from the viewpoint of how the bicycle swerved to avoid hitting the obstacle. We found that the conditions of riding a bicycle with an umbrella caused a larger swerve to avoid the obstacle than those conditions when the rider did not have an umbrella. In particular, the condition in which the obstacle was a pedestrian who also had an umbrella caused the largest swerve. Furthermore, the distance required to become aligned with the sidewalk when the obstacle was a pedestrian walking toward the cyclist was longer than that for other obstacles. The swerve width data showed interesting results, including a tendency for swerve width to be wider when the obstacle was a utility pole compared with other obstacles.

  2. Generalization of affective learning about faces to perceptually similar faces.

    Science.gov (United States)

    Verosky, Sara C; Todorov, Alexander

    2010-06-01

    Different individuals have different (and different-looking) significant others, friends, and foes. The objective of this study was to investigate whether these social face environments can shape individual face preferences. First, participants learned to associate faces with positive, neutral, or negative behaviors. Then, they evaluated morphs combining novel faces with the learned faces. The morphs (65% and 80% novel faces) were within the categorical boundary of the novel faces: They were perceived as those faces in a preliminary study. Moreover, a second preliminary study showed that following the learning, the morphs' categorization as similar to the learned faces was indistinguishable from the categorization of actual novel faces. Nevertheless, in the main experiment, participants evaluated morphs of "positive" faces more positively than morphs of "negative" faces. This learning generalization effect increased as a function of the similarity of the novel faces to the learned faces. The findings suggest that general learning mechanisms based on similarity can account for idiosyncratic face preferences.

  3. Obstacles a l'inclusion scolaire des enfants d'age prescolaire ayant des besoins speciaux. [Obstacles to Inclusion of Preschool-Age Special Needs Children.

    Science.gov (United States)

    Tetreault, Sylvie; Beaupre, Pauline; Giroux, Martine; Gagne, Marie-eve; Guerard, Lucie

    2001-01-01

    Identifies obstacles faced by young children with special needs when trying to integrate into school. Proposes new strategies to prepare and support personnel involved during transition and inclusion in the school setting. Details group discussion of parents, care center educators, teachers, and administrators that resulted in a transition plan.…

  4. Tracked robot controllers for climbing obstacles autonomously

    Science.gov (United States)

    Vincent, Isabelle

    2009-05-01

    Research in mobile robot navigation has demonstrated some success in navigating flat indoor environments while avoiding obstacles. However, the challenge of analyzing complex environments to climb obstacles autonomously has had very little success due to the complexity of the task. Unmanned ground vehicles currently exhibit simple autonomous behaviours compared to the human ability to move in the world. This paper presents the control algorithms designed for a tracked mobile robot to autonomously climb obstacles by varying its tracks configuration. Two control algorithms are proposed to solve the autonomous locomotion problem for climbing obstacles. First, a reactive controller evaluates the appropriate geometric configuration based on terrain and vehicle geometric considerations. Then, a reinforcement learning algorithm finds alternative solutions when the reactive controller gets stuck while climbing an obstacle. The methodology combines reactivity to learning. The controllers have been demonstrated in box and stair climbing simulations. The experiments illustrate the effectiveness of the proposed approach for crossing obstacles.

  5. Improved obstacle avoidance and navigation for an autonomous ground vehicle

    Science.gov (United States)

    Giri, Binod; Cho, Hyunsu; Williams, Benjamin C.; Tann, Hokchhay; Shakya, Bicky; Bharam, Vishal; Ahlgren, David J.

    2015-01-01

    This paper presents improvements made to the intelligence algorithms employed on Q, an autonomous ground vehicle, for the 2014 Intelligent Ground Vehicle Competition (IGVC). In 2012, the IGVC committee combined the formerly separate autonomous and navigation challenges into a single AUT-NAV challenge. In this new challenge, the vehicle is required to navigate through a grassy obstacle course and stay within the course boundaries (a lane of two white painted lines) that guide it toward a given GPS waypoint. Once the vehicle reaches this waypoint, it enters an open course where it is required to navigate to another GPS waypoint while avoiding obstacles. After reaching the final waypoint, the vehicle is required to traverse another obstacle course before completing the run. Q uses modular parallel software architecture in which image processing, navigation, and sensor control algorithms run concurrently. A tuned navigation algorithm allows Q to smoothly maneuver through obstacle fields. For the 2014 competition, most revisions occurred in the vision system, which detects white lines and informs the navigation component. Barrel obstacles of various colors presented a new challenge for image processing: the previous color plane extraction algorithm would not suffice. To overcome this difficulty, laser range sensor data were overlaid on visual data. Q also participates in the Joint Architecture for Unmanned Systems (JAUS) challenge at IGVC. For 2014, significant updates were implemented: the JAUS component accepted a greater variety of messages and showed better compliance to the JAUS technical standard. With these improvements, Q secured second place in the JAUS competition.

  6. Obstacle Avoidance Through Visual Teleoperation

    Directory of Open Access Journals (Sweden)

    Muhammad Usman Keerio

    2009-01-01

    Full Text Available This paper presents a novel controlling approach forHumanoid Robot to work safely in critical situations like badlight environment using Visual Teleoperation. In this regardmodeling environments for Humanoid Teleoperation Systemis developed. Here virtual reality modeling environmentincludes development of virtual Humanoid BHR-2, andvirtual objects like table etc. The main goal of this work is toenhance our visual teleoperation system for BHR-2 in orderto avoid any collision during real time operation. SoftwareMaya is used for modeling and simulations. Maya plug-insin VC++ provides efficient modeling rule, real timeinteraction, and time saving rendering approach in a virtualenvironment. In this paper the validity of proposed scheme isshown by conducting experiments using offline step overtrajectory to avoid obstacle in bad light environment.

  7. Obstacles and foliage discrimination using lidar

    Science.gov (United States)

    Morris, Daniel D.

    2016-05-01

    A central challenge to autonomous off-road navigation is discriminating between obstacles that are safe to drive over and those that pose a hazard to navigation and so must be circumnavigated. Foliage, which can often be safely driven over, presents two important perception problems. First, foliage can appear as a large impenetrable obstacle, and so must be discriminated from other objects. Second, real obstacles are much harder to detect when adjacent to or occluded by foliage and many detection methods fail to detect them due to additional clutter and partial occlusions from foliage. This paper addresses both the discrimination of foliage, and the detection of obstacles in and near foliage using Lidar. Our approach uses neighboring pixels in a depth image to construct features at each pixel that provide local surface properites. A generative model for obstacles is used to accumulate probabilistic evidence for obstacles and foliage in the vicinity of a moving platform. Detection of obstacles is then based on evidence within overlapping cells of a map without the need to segment segment obstacles and foliage. High accuracy obstacle and foliage discrimination is obtained and compared with the use of a point scatter measure.

  8. Factors influencing obstacle crossing performance in patients with Parkinson's disease.

    Directory of Open Access Journals (Sweden)

    Ying-Yi Liao

    Full Text Available BACKGROUND: Tripping over obstacles is the major cause of falls in community-dwelling patients with Parkinson's disease (PD. Understanding the factors associated with the obstacle crossing behavior may help to develop possible training programs for crossing performance. This study aimed to identify the relationships and important factors determining obstacle crossing performance in patients with PD. METHODS: Forty-two idiopathic patients with PD (Hoehn and Yahr stages I to III participated in this study. Obstacle crossing performance was recorded by the Liberty system, a three-dimensional motion capture device. Maximal isometric strength of the lower extremity was measured by a handheld dynamometer. Dynamic balance and sensory integration ability were assessed using the Balance Master system. Movement velocity (MV, maximal excursion (ME, and directional control (DC were obtained during the limits of stability test to quantify dynamic balance. The sum of sensory organization test (SOT scores was used to quantify sensory organization ability. RESULTS: Both crossing stride length and stride velocity correlated significantly with lower extremity muscle strength, dynamic balance control (forward and sideward, and sum of SOT scores. From the regression model, forward DC and ankle dorsiflexor strength were identified as two major determinants for crossing performance (R(2 = .37 to.41 for the crossing stride length, R(2 = .43 to.44 for the crossing stride velocity. CONCLUSIONS: Lower extremity muscle strength, dynamic balance control and sensory integration ability significantly influence obstacle crossing performance. We suggest an emphasis on muscle strengthening exercises (especially ankle dorsiflexors, balance training (especially forward DC, and sensory integration training to improve obstacle crossing performance in patients with PD.

  9. Overcoming Obstacles to Drug Abuse Research with Families.

    Science.gov (United States)

    Glynn, Thomas J.

    Although there has been a significant amount of research on the families of drug abusers, this field has encountered a number of obstacles to its continued growth. Some of these problems include an emphasis of research on opiate use, methodological hindrances, and lack of a constituency. A review of two concurrent national processes, the White…

  10. Sex Education in Spain: Teachers' Views of Obstacles

    Science.gov (United States)

    Martinez, Jose L.; Carcedo, Rodrigo J.; Fuertes, Antonio; Vicario-Molina, Isabel; Fernandez-Fuertes, Andres A.; Orgaz, Begona

    2012-01-01

    This paper offers an overview of the current state, difficulties, limitations and future possibilities for sex education in Spain. On the basis of a study involving 3760 teachers from all provinces in Spain, a detailed analysis of the obstacles at legislative, school and teacher levels was developed. Significant weaknesses were found at each of…

  11. Provider barriers to telemental health: obstacles overcome, obstacles remaining.

    Science.gov (United States)

    Brooks, Elizabeth; Turvey, Carolyn; Augusterfer, Eugene F

    2013-06-01

    Many providers are hesitant to use telemental health technologies. When providers are queried, various barriers are presented, such as the clinician's skepticism about the effectiveness of telemental health (TMH), viewing telehealth technologies as inconvenient, or reporting difficulties with medical reimbursement. Provider support for TMH is critical to its diffusion because clinicians often serve as the initial gatekeepers to telehealth implementation and program success. In this article, we address provider concerns in three broad domains: (1) personal barriers, (2) clinical workflow and technology barriers, and (3) licensure, credentialing, and reimbursement barriers. We found evidence that, although many barriers have been discussed in the literature for years, advancements in TMH have rapidly reduced obstacles for its use. Improvements include extensive opportunities for training, a growing evidence base supporting positive TMH outcomes, and transformations in technologies that improve provider convenience and transmission quality. Recommendations for further change are discussed within each domain. In particular, it is important to grow and disseminate data underscoring the promise and effectiveness of TMH, integrate videoconferencing capabilities into electronic medical record platforms, expand TMH reimbursement, and modify licensure standards.

  12. 沙丘背风侧气流及其沉积类型与意义%Lee-face Airflow, Depositional Types and Its Significance

    Institute of Scientific and Technical Information of China (English)

    哈斯; 王贵勇; 董光荣

    2001-01-01

    deposits. Also, the resulting deposition would consist grainflow cross-strata, and direction of dune a dvance would be perpendicular to the lee face. In this case, the dip direction of cross bedding would be the same to the primary wind direction. In oblique flow condit ions, the deflected flow controlled the lee-slops and sands from stoss-slop not deposited but transported along the lee-slop. As a result, migrating wind rippl e or smaller dunes (in the case of dune lee-slop with enough size) were the only processes operating on the lee-slop except the narrow belt of upper slop near dune crest. The deposition resulting from such flow conditions would consist of cl imb ing ripple cross-lamina or compound cross strata with grainflow cross-strata s ep arated by second-order bounding surfaces. The dip direction of climbing ripple l amina is a function of underlying slops so that could not reflect the primary wi nd direction in most cases. The dip direction of the cross-strata resulting fro m superposed dunes on larger ones indicates only lee face secondary flow directio n and does not the primary wind direction. The dips of the second-order boundin g surface is in accordance with the orientation of lee slop could indicate primary wind direction in the case of complex transverse deposit but not to longitudinal or other complex bedforms. Accordingly, because of the variation of regional flow is filtrated by dune and flow interaction, the dip directions of most aeolian cross-strata except simple grainflow cross strata resulting from simple transve rse dunes could not accurately reflect paleaowind direction.%在腾格里沙漠东南缘对现代沙丘表面气流、沉积过程的野外观测结果表明,由于区域气流、沙丘形态及其相互作用等的不同使沙丘背风坡气流发生变化,在此发现三种背风坡次生气流:分离流、附体未偏向流和附体偏向流。前者以弱的反向流为特征多发生在横向气流条件下坡度较陡的背

  13. Intelligent Surveillance Robot with Obstacle Avoidance Capabilities Using Neural Network.

    Science.gov (United States)

    Budiharto, Widodo

    2015-01-01

    For specific purpose, vision-based surveillance robot that can be run autonomously and able to acquire images from its dynamic environment is very important, for example, in rescuing disaster victims in Indonesia. In this paper, we propose architecture for intelligent surveillance robot that is able to avoid obstacles using 3 ultrasonic distance sensors based on backpropagation neural network and a camera for face recognition. 2.4 GHz transmitter for transmitting video is used by the operator/user to direct the robot to the desired area. Results show the effectiveness of our method and we evaluate the performance of the system.

  14. A New Obstacle Avoidance Method for Service Robots in Indoor Environments

    Directory of Open Access Journals (Sweden)

    Widodo Budiharto

    2012-07-01

    Full Text Available The objective of this paper is to propose an obstacle avoidance method for service robots in indoor environments using vision and ultrasonic sensors. The service robot in this research is programmed to deliver a drinking cup to the recognized customer from a specified starting point. We have developed three main modules: one for face recognition, one to identify obstacles, and one to maneuver. The detection of static obstacles, which is based on information from the landmark, uses an edge-detection method and is used to generate a planned path. The speed, direction and distance of the moving obstacle are measured by using vision and distance sensors in order for the robot to make a maneuver. Algorithms for obstacle avoidance for service robots are proposed and a new geometrical model is introduced for service robots to make a good avoidance maneuver. The main aim of this research is to provide a complete mechanism for obstacle avoidance by a vision-based service robot, whereas popular obstacle avoidance methods such as PVM do not provide such a feature. We present the results of an experiment with a service robot in which our proposed method was implemented, after which we evaluate its performance.

  15. Obstacles and problems of ethical leadership from the perspective of nursing leaders: a qualitative content analysis.

    Science.gov (United States)

    Barkhordari-Sharifabad, Maasoumeh; Ashktorab, Tahereh; Atashzadeh-Shoorideh, Foroozan

    2017-01-01

    In the nursing profession, leadership plays a significant role in creating motivation and thus enabling nurses to provide high quality care. Ethics is an essential component of leadership qualifications and the ethical leader can help create an ethical atmosphere, offer ethical guidance, and ensure the occupational satisfaction of personnel through prioritizing moralities. However, some issues prevent the implementation of this type of leadership by nursing leaders. The aim of this study was to identify and describe some problems and obstacles in ethical leadership faced by nursing leaders, and to help them achieve more accurate information and broader perspective in this field. The present study was conducted using a qualitative approach and content analysis. A total of 14 nursing managers and educators were selected purposefully, and deep and semi-structured interviews were conducted with them. Content analysis was performed using an inductive approach. Three main categories were obtained after data analysis: ethical, cultural and managerial problems. "Ethical problems" pertain to doubt in ethical actions, ethical conflicts and ethical distress; "cultural problems" include organizational and social culture; and "managerial problems" are connected to organizational and staff-related issues. Nursing leaders put forth various aspects of the problems associated with ethical leadership in the clinical setting. This style of leadership could be promoted by developing suitable programs and providing clear-cut strategies for removing the current obstacles and correcting the organizational structure. This can lead to ethical improvement in nursing leaders and subsequently the nurses.

  16. Real-Time Obstacle Avoidance for Telerobotic Systems Based on Equipotential Surface

    Directory of Open Access Journals (Sweden)

    Xin Li

    2012-09-01

    Full Text Available Redundant manipulators offer a dual advantage of flexibility and dexterity and can be used in many civilian and military areas. However, operating such systems by teleoperation is challenging because of the redundancy and unstructured task environment, which result in the human operator suffering a huge burden when telemanipulator is facing the complicated obstacles. The existing methods usually use some off‐line algorithms to solve the problem of obstacle avoidance. It is difficult for them to meet the requirements of real‐time teleoperation in some unknown environment. This paper presents an on‐line method for a telerobotic system to take advantage of redundancy to avoid obstacle, which is based on real‐time sensor information. With this method, the human operator can focus attention on the end‐effector operation regardless of the obstacle avoidance of other parts. The effectiveness and advantage of the method are well demonstrated by experiments.

  17. Socio-Economic Mobility of Youth: Factors, Obstacles, and Potential Solutions

    Directory of Open Access Journals (Sweden)

    Andrew Leon Hanna

    2015-03-01

    Full Text Available In the face of record levels of youth unemployment and starkly unequal opportunities to climb the socioeconomic ladder, young people are facing difficult challenges. From early childhood to young adulthood, there are several key obstacles to socioeconomic mobility that emerge. These include availability of early childhood education, level of peer support during adolescence, secondary school funding and quality, and skills development and job matching as a young adult. This article explores the dynamics of these critical obstacles, analyzes initiatives that are successfully helping young people overcome these obstacles around the world, and makes policy suggestions to create a society in which young people have strong opportunities to fulfill their potentials and advance socioeconomically. The article focuses on the state of socioeconomic mobility of young people in the United States, drawing on examples of successful models from all over the globe.

  18. Research-based Reflections on How the Educational, Economic and Social Circumstances Faced by Some Children and Young People Can Lead to Significant Disadvantage and Vulnerability

    Directory of Open Access Journals (Sweden)

    Tucker Stanley

    2016-07-01

    Full Text Available The paper provides detailed reflections on the educational, economic and social circumstances that impact on the lives of many disadvantaged and vulnerable children and young people. Drawing largely on primary research data collected in Romania, Germany and the United Kingdom, three illustrative case studies are presented for consideration focusing on: life in residential care and youth offending institutions; experiences of educational vulnerability; and human trafficking. The methodological approach adopted across the research projects explored, was shaped by the demands and expectations of the United Nations Convention on the Rights of the Child (UNCRC. All of the reported data reflects the views of children and young people who were interviewed as part of three research projects. It is argued that the difficult and challenging circumstances that many children and young people find themselves in, place them at significant disadvantage and increased vulnerability in terms of their social and educational development and life chances.

  19. Face pain

    Science.gov (United States)

    ... begin in other places in the body. Abscessed tooth (ongoing throbbing pain on one side of the lower face that ... face, and aggravated by eating. Call a dentist. Pain is persistent, ... by other unexplained symptoms. Call your primary provider.

  20. A Global Obstacle-avoidance Map for Anthropomorphic Arms

    Directory of Open Access Journals (Sweden)

    Cheng Fang

    2014-07-01

    Full Text Available More and more humanoid robots are used in human society, and they face a wide variety of complicated manipulation tasks, which are mainly to be achieved by their anthropomorphic arms. Obstacle avoidance for the anthropomorphic arm must be a fundamental consideration to guarantee the successful implementation of these tasks. Different from traditional methods searching for feasible or optimal collision-free solutions for the anthropomorphic arm, a global obstacle- avoidance map for the whole arm is proposed to indicate the complete set of feasible solutions. In this map, the motion of the arm can be appropriately planned to intuitively control the configuration of the arm in motion. First, the cubic spline function is adopted to interpolate some well-chosen path points to generate a smooth collision-free path for the wrist of the anthropomorphic arm. Second, based on the path function of the wrist, the time and the self-rotation angle of the arm about the “shoulder-wrist” axis are used to parameterize all possible configurations of the arm so that a global two- dimensional map considering the obstacle avoidance can be established. Subsequently, a collision-free self-rotation angle profile of the arm can be well planned. Finally, the joint trajectories of a specific anthropomorphic arm, which correspond to the planned path of the wrist and self-rotation angle profile of the arm, can be solved on the basis of the general kinematic analysis of the anthropomorphic arm, and the specific structure. Several simulations are conducted to verify that the proposed collision-free motion planning method for anthropomorphic arms has some advantages and can be regarded as a convenient and intuitive tool to control the configuration of the anthropomorphic arm in motion, without collision with obstacles in its surroundings.

  1. Identification and analysis of obstacles in bioterrorism preparedness and response

    Science.gov (United States)

    Sincavage, Suzanne Michele

    The focus of this study was to identify and analyze the obstacles to bioterrorism preparedness and response facing emergency management agencies and public authorities. In order to establish the limits of this discussion, the obstacles will examine a combined conceptual framework of public health, environmental security and social response. The interdisciplinary characteristics of this framework are ideal for addressing the issue of bioterrorism because of its simultaneous impact, which encompasses the complex interrelationships that pertain to public health and national security and social response. Based on a review of literature, the obstacles presented range from the absence of an effective surveillance system for biological terrorism related diseases to the inadequate training of first responders in bioterrorism preparedness and the difficult challenges of a mass casualty situation and the intense pressures associated with the crisis response. Furthermore, the impending reality of bioterrorism will further illustrate a close examination of the characteristics and management of three major biowarfare agents---anthrax, plague and smallpox. Finally, to provide a realistic understanding of the impact of bioterrorism, three case studies of actual events and two hypothetical scenarios will be discussed. Specifically, the discussion will provide the following three unconventional terrorist attacks: the recent anthrax attacks of 2001, the Aum Shinrikyo's attack of the Tokyo subway in 1995, and the Rajneeshees' use of salmonella poisoning in 1994. The inclusion of the hypothetical scenarios of two massive outbreaks of smallpox and anthrax will be presented to illuminate the seriousness and magnitude of the threat of bioterrorism and the probable consequences of failing to overcome the obstacles presented in this study. The importance of this research cannot be overemphasized, the threat is undeniably serious, and the potential for biological agents to cause devastating

  2. ASPECTS OF OBSTACLES FOR APPLYING ACTIVITY BASED COSTING (ABC SYSTEM IN EGYPTIAN FIRMS

    Directory of Open Access Journals (Sweden)

    Petru STEFEA

    2013-10-01

    Full Text Available The following investigation aims to determine the aspects of obstacles for applying Activity Based Costing (ABC system in the Egyptian case and the significant differences among the effects of such obstacles . The Study used the survey method to describe and analyze the obstacles in some Egyptian firms. The population of the study is Egyptian manufacturing firms. This survey used the number of 392 questionnaires that were used throughout the total of 23 Egyptian manufacturing firms, during the first half of 2013. Finally, the study found some influencing obstacles for applying this system (ABC and there were significant differences among the aspects of obstacles for applying ABC system in the Egyptian manufacturing firms.

  3. Hypertext Links to Learning: Roadblocks and Obstacles along the Information Super Highway.

    Science.gov (United States)

    Daly, Joanne English

    1998-01-01

    Addresses the following obstacles faced by faculty and students in the use of World Wide Web-based support and instruction: multiple skill levels of students performing Web research; credibility of Web information; reliability of campus computer-network systems; inequality of access to student computing resources; and lack of understanding of…

  4. Examining the Obstacles and Possible Solutions for Improving Science Education in Southern Mexico

    Science.gov (United States)

    Cisneros-Cohernour, Edith Juliana; Avila, Maria Teresa Lopez; Lara, Mario Baas

    2005-01-01

    The purpose of this qualitative study was to obtain a better understanding of the obstacles and possible solutions for improving science education in Southern Mexico. It provides information about the challenges faced by teachers and school administrators, and possible alternatives for improving the quality of teaching after ten years of a…

  5. The Obstacle Problem for the -Harmonic Equation

    Directory of Open Access Journals (Sweden)

    Bao Gejun

    2010-01-01

    Full Text Available Firstly, we define an order for differential forms. Secondly, we also define the supersolution and subsolution of the -harmonic equation and the obstacle problems for differential forms which satisfy the -harmonic equation, and we obtain the relations between the solutions to -harmonic equation and the solution to the obstacle problem of the -harmonic equation. Finally, as an application of the obstacle problem, we prove the existence and uniqueness of the solution to the -harmonic equation on a bounded domain with a smooth boundary , where the -harmonic equation satisfies where is any given differential form which belongs to .

  6. Speeded reaching movements around invisible obstacles.

    Directory of Open Access Journals (Sweden)

    Todd E Hudson

    Full Text Available We analyze the problem of obstacle avoidance from a Bayesian decision-theoretic perspective using an experimental task in which reaches around a virtual obstacle were made toward targets on an upright monitor. Subjects received monetary rewards for touching the target and incurred losses for accidentally touching the intervening obstacle. The locations of target-obstacle pairs within the workspace were varied from trial to trial. We compared human performance to that of a Bayesian ideal movement planner (who chooses motor strategies maximizing expected gain using the Dominance Test employed in Hudson et al. (2007. The ideal movement planner suffers from the same sources of noise as the human, but selects movement plans that maximize expected gain in the presence of that noise. We find good agreement between the predictions of the model and actual performance in most but not all experimental conditions.

  7. Three Obstacles to Improving Academic Consultation.

    Science.gov (United States)

    Kremer, John F.

    1980-01-01

    Notes three obstacles to improving academic consultation to students: (1) lack of knowledge of techniques to improve student performance; (2) reduction of barriers between students and professors; and (3) needed reinforcements for professors. Suggests strategies for overcoming those problems. (CK)

  8. Scattering of electromagnetic waves by obstacles

    CERN Document Server

    Kristensson, Gerhard

    2016-01-01

    The main purpose of Scattering of Electromagnetic Waves by Obstacles is to give a theoretical treatment of the scattering phenomena, and to illustrate numerical computations of some canonical scattering problems for different geometries and materials.

  9. Optical Flow based Robot Obstacle Avoidance

    Directory of Open Access Journals (Sweden)

    Kahlouche Souhila

    2008-11-01

    Full Text Available In this paper we try to develop an algorithm for visual obstacle avoidance of autonomous mobile robot. The input of the algorithm is an image sequence grabbed by an embedded camera on the B21r robot in motion. Then, the optical flow information is extracted from the image sequence in order to be used in the navigation algorithm. The optical flow provides very important information about the robot environment, like: the obstacles disposition, the robot heading, the time to collision and the depth. The strategy consists in balancing the amount of left and right side flow to avoid obstacles, this technique allows robot navigation without any collision with obstacles. The robustness of the algorithm will be showed by some examples.

  10. Statistics of dislocation pinning at localized obstacles

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, A. [S. N. Bose National Centre for Basic Sciences, Salt Lake, Kolkata 700098 (India); Bhattacharya, M., E-mail: mishreyee@vecc.gov.in; Barat, P. [Variable Energy Cyclotron Centre, 1/AF Bidhannagar, Kolkata 700064 (India)

    2014-10-14

    Pinning of dislocations at nanosized obstacles like precipitates, voids, and bubbles is a crucial mechanism in the context of phenomena like hardening and creep. The interaction between such an obstacle and a dislocation is often studied at fundamental level by means of analytical tools, atomistic simulations, and finite element methods. Nevertheless, the information extracted from such studies cannot be utilized to its maximum extent on account of insufficient information about the underlying statistics of this process comprising a large number of dislocations and obstacles in a system. Here, we propose a new statistical approach, where the statistics of pinning of dislocations by idealized spherical obstacles is explored by taking into account the generalized size-distribution of the obstacles along with the dislocation density within a three-dimensional framework. Starting with a minimal set of material parameters, the framework employs the method of geometrical statistics with a few simple assumptions compatible with the real physical scenario. The application of this approach, in combination with the knowledge of fundamental dislocation-obstacle interactions, has successfully been demonstrated for dislocation pinning at nanovoids in neutron irradiated type 316-stainless steel in regard to the non-conservative motion of dislocations. An interesting phenomenon of transition from rare pinning to multiple pinning regimes with increasing irradiation temperature is revealed.

  11. Obstacles to implementing evidence-based dentistry: a focus group-based study.

    Science.gov (United States)

    Hannes, Karin; Norré, David; Goedhuys, Jo; Naert, Ignace; Aertgeerts, Bert

    2008-06-01

    In many countries, questions have been raised about the use of evidence-based practice (EBP) in oral health care. The call for an increase in EBP seems to face many obstacles. Only limited empirical studies address these obstacles. We present a qualitative study that explores the obstacles that Flemish (Belgian, Dutch-speaking) dentists experience in the implementation of EBP in routine clinical work. We collected data from discussions in focus groups. Seventy-nine dentists participated. The data were analyzed using constant comparative analysis. Three major categories of obstacles were identified. These categories relate to obstacles in 1) evidence, 2) partners in health care (medical doctors, patients, and government), and 3) the field of dentistry. Our findings suggest that educators should provide communication skills to aid decision making, address the technical dimensions of dentistry, promote lifelong learning, and close the gap between academics and general practitioners (dentists) in order to create mutual understanding. The obstacles identified are considered useful to support future quantitative research that can be generalized to a broader group.

  12. The composite face illusion.

    Science.gov (United States)

    Murphy, Jennifer; Gray, Katie L H; Cook, Richard

    2017-04-01

    Few findings in cognitive science have proved as influential as the composite face effect. When the top half of one face is aligned with the bottom half of another, and presented upright, the resulting composite arrangement induces a compelling percept of a novel facial configuration. Findings obtained using composite face procedures have contributed significantly to our understanding of holistic face processing, the detrimental effects of face inversion, the development of face perception, and aberrant face perception in clinical populations. Composite paradigms continue to advance our knowledge of face perception, as exemplified by their recent use for investigating the perceptual mechanisms underlying dynamic face processing. However, the paradigm has been the subject of intense scrutiny, particularly over the last decade, and there is a growing sense that the composite face illusion, whilst easy to illustrate, is deceptively difficult to measure and interpret. In this review, we provide a focussed overview of the existing composite face literature, and identify six priorities for future research. Addressing these gaps in our knowledge will aid the evaluation and refinement of theoretical accounts of the illusion.

  13. Distracting visuospatial attention while approaching an obstacle reduces the toe-obstacle clearance.

    Science.gov (United States)

    Lo, On-Yee; van Donkelaar, Paul; Chou, Li-Shan

    2015-04-01

    Obstacle crossing during walking requires visuospatial attention to identify the obstacle, so that individuals can integrate visual and somatosensory information for raising the foot with appropriate height and timing without being tripped. However, the interaction between control of foot trajectory and orientation of visuospatial attention during obstacle crossing is complicated and remains unclear. This study probed where attention is directed when approaching and stepping over an obstacle during gait and examined how the presence of the obstacle affects the distribution of attention during walking. Eleven young healthy adults performed a visuospatial attention task while standing (Stand), crossing over an obstacle placed either before (ObsBefore) or after (ObsAfter) the visual target, or crossing without the visual target (ObsOnly). Toe-obstacle clearance was reduced for the trailing leg in the ObsAfter condition but remained the same for the ObsBefore and ObsOnly conditions. In addition, the accuracy rate of the visuospatial attention task tended to be higher at the locations closer to the obstacle. Taken together, these results demonstrate that visuospatial attention and the processes underlying obstacle crossing during locomotion interact in both a spatially and temporally dependent manner.

  14. Avoiding unseen obstacles: Subcortical vision is not sufficient to maintain normal obstacle avoidance behaviour during reaching.

    Science.gov (United States)

    Ross, Alasdair I; Schenk, Thomas; Billino, Jutta; Macleod, Mary J; Hesse, Constanze

    2016-10-03

    Previous research found that a patient with cortical blindness (homonymous hemianopia) was able to successfully avoid an obstacle placed in his blind field, despite reporting no conscious awareness of it [Striemer, C. L., Chapman, C. S., & Goodale, M. A., 2009, PNAS, 106(37), 15996-16001]. This finding led to the suggestion that dorsal stream areas, that are assumed to mediate obstacle avoidance behaviour, may obtain their visual input primarily from subcortical pathways. Hence, it was suggested that normal obstacle avoidance behaviour can proceed without input from the primary visual cortex. Here we tried to replicate this finding in a group of patients (N = 6) that suffered from highly circumscribed lesions in the occipital lobe (including V1) that spared the subcortical structures that have been associated with action-blindsight. We also tested if obstacle avoidance behaviour differs depending on whether obstacles are placed only in the blind field or in both the blind and intact visual field of the patients simultaneously. As expected, all patients successfully avoided obstacles placed in their intact visual field. However, none of them showed reliable avoidance behaviour - as indicated by adjustments in the hand trajectory in response to obstacle position - for obstacles placed in their blind visual field. The effects were not dependent on whether one or two obstacles were present. These findings suggest that behaviour in complex visuomotor tasks relies on visual input from occipital areas.

  15. Obstacle crossing following stroke improves over one month when the unaffected limb leads, but not when the affected limb leads.

    Science.gov (United States)

    Said, Catherine M; Galea, Mary; Lythgo, Noel

    2014-01-01

    While it is well established that obstacle crossing is impaired following stroke, it is not known whether obstacle crossing improves as gait improves following stroke. The purpose of this study was to determine whether obstacle crossing changed over a one month time period in people with a recent stroke. Twenty participants receiving rehabilitation following a recent stroke were tested on two occasions one month apart. Participants received usual care rehabilitation, including physiotherapy, between the tests. The main outcome measure was obstacle crossing speed as participants stepped over a 4-cm high obstacle. Secondary measures were spatiotemporal variables. Data were collected via a three dimensional motion analysis system. When leading with the affected limb no changes in obstacle crossing speed or spatiotemporal variables were observed over the one month period. When leading with the unaffected limb, crossing speed significantly increased (p=.002), and affected trail limb swing time (p=.03) and crossing step double support time reduced (p=.016). While not significant, the lead and trail limb pre-obstacle distance increased (p=.08), and lead swing time (p=.052) reduced. Change in obstacle crossing speed did not correlate with change in level gait speed. Obstacle crossing does not necessarily improve over a one month time period in people receiving rehabilitation following stroke. These findings suggest that there may be a need for more targeted training of obstacle crossing, particularly when leading with the affected limb.

  16. Effects of soft interactions and bound mobility on diffusion in crowded environments: a model of sticky and slippery obstacles

    Science.gov (United States)

    Stefferson, Michael W.; Norris, Samantha L.; Vernerey, Franck J.; Betterton, Meredith D.; E Hough, Loren

    2017-08-01

    Crowded environments modify the diffusion of macromolecules, generally slowing their movement and inducing transient anomalous subdiffusion. The presence of obstacles also modifies the kinetics and equilibrium behavior of tracers. While previous theoretical studies of particle diffusion have typically assumed either impenetrable obstacles or binding interactions that immobilize the particle, in many cellular contexts bound particles remain mobile. Examples include membrane proteins or lipids with some entry and diffusion within lipid domains and proteins that can enter into membraneless organelles or compartments such as the nucleolus. Using a lattice model, we studied the diffusive movement of tracer particles which bind to soft obstacles, allowing tracers and obstacles to occupy the same lattice site. For sticky obstacles, bound tracer particles are immobile, while for slippery obstacles, bound tracers can hop without penalty to adjacent obstacles. In both models, binding significantly alters tracer motion. The type and degree of motion while bound is a key determinant of the tracer mobility: slippery obstacles can allow nearly unhindered diffusion, even at high obstacle filling fraction. To mimic compartmentalization in a cell, we examined how obstacle size and a range of bound diffusion coefficients affect tracer dynamics. The behavior of the model is similar in two and three spatial dimensions. Our work has implications for protein movement and interactions within cells.

  17. Obstacles for Teachers to Integrate Technology with Instruction

    Science.gov (United States)

    Alenezi, Abdullah

    2017-01-01

    This paper covers type one and two educational obstacles in using technology in the classrooms, and considering those obstacles tries to find the answer to the following overarching research question which can help to gauge some obstacles for the educational technology integration for elementary and high school education: What obstacles do…

  18. Robotic-Vehicle Perception Control For Detecting Obstacles

    Science.gov (United States)

    Grandjean, Pierrick C.; Matthies, Larry H.

    1995-01-01

    Obstacle-detection systems designed to make most of limited data-processing resources. Bump or step identified, from stereoscopic images of scene ahead, by obstacle-detection algorithm. If bump or step exceeds specified step height, marked as obstacle, and control actions taken to avoid obstacle.

  19. Facing Aggression: Cues Differ for Female versus Male Faces

    Science.gov (United States)

    Geniole, Shawn N.; Keyes, Amanda E.; Mondloch, Catherine J.; Carré, Justin M.; McCormick, Cheryl M.

    2012-01-01

    The facial width-to-height ratio (face ratio), is a sexually dimorphic metric associated with actual aggression in men and with observers' judgements of aggression in male faces. Here, we sought to determine if observers' judgements of aggression were associated with the face ratio in female faces. In three studies, participants rated photographs of female and male faces on aggression, femininity, masculinity, attractiveness, and nurturing. In Studies 1 and 2, for female and male faces, judgements of aggression were associated with the face ratio even when other cues in the face related to masculinity were controlled statistically. Nevertheless, correlations between the face ratio and judgements of aggression were smaller for female than for male faces (F1,36 = 7.43, p = 0.01). In Study 1, there was no significant relationship between judgements of femininity and of aggression in female faces. In Study 2, the association between judgements of masculinity and aggression was weaker in female faces than for male faces in Study 1. The weaker association in female faces may be because aggression and masculinity are stereotypically male traits. Thus, in Study 3, observers rated faces on nurturing (a stereotypically female trait) and on femininity. Judgements of nurturing were associated with femininity (positively) and masculinity (negatively) ratings in both female and male faces. In summary, the perception of aggression differs in female versus male faces. The sex difference was not simply because aggression is a gendered construct; the relationships between masculinity/femininity and nurturing were similar for male and female faces even though nurturing is also a gendered construct. Masculinity and femininity ratings are not associated with aggression ratings nor with the face ratio for female faces. In contrast, all four variables are highly inter-correlated in male faces, likely because these cues in male faces serve as “honest signals”. PMID:22276184

  20. Performance Impact of Deflagration to Detonation Transition Enhancing Obstacles

    Science.gov (United States)

    Paxson, Daniel E.; Schauer, Frederick; Hopper, David

    2012-01-01

    A sub-model is developed to account for the drag and heat transfer enhancement resulting from deflagration-to-detonation (DDT) inducing obstacles commonly used in pulse detonation engines (PDE). The sub-model is incorporated as a source term in a time-accurate, quasi-onedimensional, CFD-based PDE simulation. The simulation and sub-model are then validated through comparison with a particular experiment in which limited DDT obstacle parameters were varied. The simulation is then used to examine the relative contributions from drag and heat transfer to the reduced thrust which is observed. It is found that heat transfer is far more significant than aerodynamic drag in this particular experiment.

  1. Inverse obstacle scattering for elastic waves

    Science.gov (United States)

    Li, Peijun; Wang, Yuliang; Wang, Zewen; Zhao, Yue

    2016-11-01

    Consider the scattering of a time-harmonic plane wave by a rigid obstacle which is embedded in an open space filled with a homogeneous and isotropic elastic medium. An exact transparent boundary condition is introduced to reduce the scattering problem into a boundary value problem in a bounded domain. Given the incident field, the direct problem is to determine the displacement of the wave field from the known obstacle; the inverse problem is to determine the obstacle’s surface from the measurement of the displacement on an artificial boundary enclosing the obstacle. In this paper, we consider both the direct and inverse problems. The direct problem is shown to have a unique weak solution by examining its variational formulation. The domain derivative is derived for the displacement with respect to the variation of the surface. A continuation method with respect to the frequency is developed for the inverse problem. Numerical experiments are presented to demonstrate the effectiveness of the proposed method.

  2. Using Large Eddy Simulation for understanding vented gas explosions in the presence of obstacles.

    Science.gov (United States)

    Di Sarli, Valeria; Di Benedetto, Almerinda; Russo, Gennaro

    2009-09-30

    In this work, a validated Large Eddy Simulation model of unsteady premixed flame propagation is used to study the phenomenology underlying vented gas explosions in the presence of obstacles. Computations are run of deflagrating flames in a small-scale combustion chamber closed at the bottom end and open at the opposite face. A single obstacle is centred inside the chamber. Methane-air mixtures of various compositions (ranging from lean to stoichiometric and rich), and obstacles with different area blockage ratios (30, 50 and 70%) and shapes (circular, rectangular and square cross-section in the flow direction) are investigated. All cases are initialized from stagnation. The competition between combustion rate and venting rate allows explaining both number and intensity of the overpressure peaks observed.

  3. About Face

    Medline Plus

    Full Text Available Skip to Content Menu Closed (Tap to Open) Home Videos by Topic Videos by Type Search All ... What is AboutFace? Resources for Professionals Get Help Home Watch Videos by Topic Videos by Type Search ...

  4. About Face

    Medline Plus

    Full Text Available ... Home Videos by Topic Videos by Type Search All Videos PTSD Basics PTSD Treatment What is AboutFace? ... Watch Videos by Topic Videos by Type Search All Videos Learn More PTSD Basics PTSD Treatment What ...

  5. General Investigations on Obstacle Courses in Romania

    Directory of Open Access Journals (Sweden)

    Flavia Luminiţa Bochiş

    2011-05-01

    Full Text Available Show jumping is an equestrian sport event, where each horse-rider couple must run in average about 12-20 obstacles, named a set course, within a specified time. Faults or penalties are collected if the couple brings down the highest element of an obstacle, if the horse refuses to jump or when the allocated time exceeds the allowed seconds. The idea of the jumping events is never to standardize the courses and types of competitions; the variety provides a precious element of interest for competitors and spectators.

  6. Obstacle mean-field game problem

    KAUST Repository

    Gomes, Diogo A.

    2015-01-01

    In this paper, we introduce and study a first-order mean-field game obstacle problem. We examine the case of local dependence on the measure under assumptions that include both the logarithmic case and power-like nonlinearities. Since the obstacle operator is not differentiable, the equations for first-order mean field game problems have to be discussed carefully. Hence, we begin by considering a penalized problem. We prove this problem admits a unique solution satisfying uniform bounds. These bounds serve to pass to the limit in the penalized problem and to characterize the limiting equations. Finally, we prove uniqueness of solutions. © European Mathematical Society 2015.

  7. Algorithm for Spatial Clustering with Obstacles

    CERN Document Server

    El-Sharkawi, Mohamed E

    2009-01-01

    In this paper, we propose an efficient clustering technique to solve the problem of clustering in the presence of obstacles. The proposed algorithm divides the spatial area into rectangular cells. Each cell is associated with statistical information that enables us to label the cell as dense or non-dense. We also label each cell as obstructed (i.e. intersects any obstacle) or non-obstructed. Then the algorithm finds the regions (clusters) of connected, dense, non-obstructed cells. Finally, the algorithm finds a center for each such region and returns those centers as centers of the relatively dense regions (clusters) in the spatial area.

  8. Face Forward

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Last November, surgeons in France successfully performed the world's first face transplant surgery. Ten days later, Chen Huanran in Beijing began soliciting patients who were ready to accept a face transplant, searching for China's first such patient through an advertisement on his website and other channels. Chen, chief orthopedic surgeon at the Plastic Surgery Hospital under the Chinese Academy of Medical Sciences, has conducted more than 300 transsexual operations and was considered one of the top com...

  9. Learning obstacle avoidance with an operant behavior model.

    Science.gov (United States)

    Gutnisky, D A; Zanutto, B S

    2004-01-01

    Artificial intelligence researchers have been attracted by the idea of having robots learn how to accomplish a task, rather than being told explicitly. Reinforcement learning has been proposed as an appealing framework to be used in controlling mobile agents. Robot learning research, as well as research in biological systems, face many similar problems in order to display high flexibility in performing a variety of tasks. In this work, the controlling of a vehicle in an avoidance task by a previously developed operant learning model (a form of animal learning) is studied. An environment in which a mobile robot with proximity sensors has to minimize the punishment for colliding against obstacles is simulated. The results were compared with the Q-Learning algorithm, and the proposed model had better performance. In this way a new artificial intelligence agent inspired by neurobiology, psychology, and ethology research is proposed.

  10. Collision Avoidance of Moving Obstacles for Underwater Robots

    Directory of Open Access Journals (Sweden)

    KWON KYOUNG YOUB

    2006-10-01

    Full Text Available A fuzzy logic for autonomous navigation of underwater robot is proposed in this paper. The VFF(Virtual Force Field algorithm, which is widely used in the field of mobile robot, is modified for application to the autonomous navigation of underwater robot. This Modified Virtual Force Field(MVFF algorithm using the fuzzy logic can be used in either track keeping or obstacle avoidance. Fuzzy logics are devised to handle various situations which can be faced during autonomous navigation of underwater robot. A graphic simulator based on OpenGL for an autonomous navigation has been developed. The good performance of the proposed MVFF algorithm is verified through computer simulations on an underwater robot.

  11. Optimal layout design of obstacles for panic evacuation using differential evolution

    Science.gov (United States)

    Zhao, Yongxiang; Li, Meifang; Lu, Xin; Tian, Lijun; Yu, Zhiyong; Huang, Kai; Wang, Yana; Li, Ting

    2017-01-01

    To improve the pedestrian outflow in panic situations by suitably placing an obstacle in front of the exit, it is vital to understand the physical mechanism behind the evacuation efficiency enhancement. In this paper, a robust differential evolution is firstly employed to optimize the geometrical parameters of different shaped obstacles in order to achieve an optimal evacuation efficiency. Moreover, it is found that all the geometrical parameters of obstacles could markedly influence the evacuation efficiency of pedestrians, and the best way for achieving an optimal pedestrian outflow is to slightly shift the obstacle from the center of the exit which is consistent with findings of extant literature. Most importantly, by analyzing the profiles of density, velocity and specific flow, as well as the spatial distribution of crowd pressure, we have proven that placing an obstacle in panic situations does not reduce or absorb the pressure in the region of exit, on the contrary, promotes the pressure to a much higher level, hence the physical mechanism behind the evacuation efficiency enhancement is not a pressure decrease in the region of exit, but a significant reduction of high density region by effective separation in space which finally causes the increasing of escape speed and evacuation outflow. Finally, it is clearly demonstrated that the panel-like obstacle is considerably more robust and stable than the pillar-like obstacle to guarantee the enhancement of evacuation efficiency under different initial pedestrian distributions, different initial crowd densities as well as different desired velocities.

  12. Critical role of blockage ratio for flame acceleration in channels with tightly spaced obstacles

    Science.gov (United States)

    Ugarte, Orlando J.; Bychkov, Vitaly; Sadek, Jad; Valiev, Damir; Akkerman, V'yacheslav

    2016-09-01

    A conceptually laminar mechanism of extremely fast flame acceleration in obstructed channels, identified by Bychkov et al. ["Physical mechanism of ultrafast flame acceleration," Phys. Rev. Lett. 101, 164501 (2008)], is further studied by means of analytical endeavors and computational simulations of compressible hydrodynamic and combustion equations. Specifically, it is shown how the obstacles length, distance between the obstacles, channel width, and thermal boundary conditions at the walls modify flame propagation through a comb-shaped array of parallel thin obstacles. Adiabatic and isothermal (cold and preheated) side walls are considered, obtaining minor difference between these cases, which opposes the unobstructed channel case, where adiabatic and isothermal walls provide qualitatively different regimes of flame propagation. Variations of the obstructed channel width also provide a minor influence on flame propagation, justifying a scale-invariant nature of this acceleration mechanism. In contrast, the spacing between obstacles has a significant role, although it is weaker than that of the blockage ratio (defined as the fraction of the channel blocked by obstacles), which is the key parameter of the problem. Evolution of the burning velocity and the dependence of the flame acceleration rate on the blockage ratio are quantified. The critical blockage ratio, providing the limitations for the acceleration mechanism in channels with comb-shaped obstacles array, is found analytically and numerically, with good agreement between both approaches. Additionally, this comb-shaped obstacles-driven acceleration is compared to finger flame acceleration and to that produced by wall friction.

  13. Healthy younger and older adults control foot placement to avoid small obstacles during gait primarily by modulating step width

    Directory of Open Access Journals (Sweden)

    Schulz Brian W

    2012-10-01

    Full Text Available Abstract Background Falls are a significant problem in the older population. Most falls occur during gait, which is primarily regulated by foot placement. Variability of foot placement has been associated with falls, but these associations are inconsistent and generally for smooth, level flooring. This study investigates the control of foot placement and the associated gait variability in younger and older men and women (N=7/group, total N=28 while walking at three different speeds (slow, preferred, and fast across a control surface with no obstacles and surfaces with multiple (64 small (10cm long ×13mm high visible and hidden obstacles. Results Minimum obstacle distance between the shoe and nearest obstacle during each footfall was greater on the visible obstacles surface for older subjects because some of them chose to actively avoid obstacles. This obstacle avoidance strategy was implemented primarily by modulating step width and to a lesser extent step length as indicated by linear regressions of step width and length variability on minimum obstacle distance. Mean gait speed, step length, step width, and step time did not significantly differ by subject group, flooring surface, or obstacle avoidance strategy. Conclusions Some healthy older subjects choose to actively avoid small obstacles that do not substantially perturb their gait by modulating step width and, to a lesser extent, step length. It is not clear if this obstacle avoidance strategy is appropriate and beneficial or overcautious and maladaptive, as it results in fewer obstacles encountered at a consequence of a less efficient gait pattern that has been shown to indicate increased fall risk. Further research is needed on the appropriateness of strategy selection when the environmental demands and/or task requirements have multiple possible completion strategies with conflicting objectives (i.e. perceived safety vs. efficiency.

  14. ASPECTS OF OBSTACLES FOR APPLYING TARGET COSTING: A SURVEY OF MANUFACTURING FIRMS IN EGYPT

    Directory of Open Access Journals (Sweden)

    Petru STEFEA

    2014-04-01

    Full Text Available The present investigation aims to determine the aspects of obstacles for applying Target Costing(TC system in Egyptian case and the significant differences among effects of these obstacles . The study used the survey method to describe and analyze the obstacles in some Egyptian firms. The population of the study is Egyptian manufacturing firms. Accordingly, the number of received questionnaires was 388 (21 Egyptian manufacturing firms in 2013. Finally, the study found that there is a significant divergence among obstacles for applying Target Costing (TC system in Egyptian manufacturing firms (Internal and external.The external dimensions are the most influence of internal dimensions, where the weakness of the competition is the highest effect in the external dimensions case but resistance top management is the highest effect in external dimensions case.

  15. Intermittent catheterization in patients with traumatic spinal cord injury: obstacles, worries, level of satisfaction.

    Science.gov (United States)

    Yılmaz, B; Akkoç, Y; Alaca, R; Erhan, B; Gündüz, B; Yıldız, N; Gök, H; Köklü, K; Cınar, E; Alemdaroğlu, E; Ersöz, M; Karapolat, H; Demir, Y; Bardak, A N; Turna, I; Catalbaş, N; Güneş, S; Tunç, H

    2014-11-01

    The aim of this study is to examine the obstacles in people with traumatic spinal cord injury (SCI) face performing intermittent catheterization (IC), also their worries and level of satisfaction. Two hundred sixty-nine patients performing IC for at least 3 months were asked to fill-out a questionnaire about their opinions on IC. In total, 69.5% of patients performed IC themselves, 10.4% had performed by their mothers, 7.8% by another caregiver and 7.4% by their spouse. For the 72 (26%) patients unable to apply IC, reasons were insufficient hand function (56.1%), being unable to sit appropriately (35.4%) and spasticity (8.5%). In all, 70% of male patients had insufficient hand function, 20% could not sit and 10% had spasticity while 56.3% of female patients could not sit, 37.5% had insufficient hand function and 63% had spasticity. Difference between sexes was found to be statistically significant (Ppatients had when starting IC were fear of being dependent on IC (50.2%), accidentally injuring self (43.8%), embarrassment (43.2%), causing an infection (40.2%), bleeding (32.7%), fear of feeling pain (30.2%) and hygiene (24.7%). More women felt embarrassment; other items were similar in both sexes. In all, 46.9% of patients had urinary incontinence in intervals. In total, 69.5% of patients performed IC themselves. Men's most common obstacle was insufficient hand function while women's was being unable to sit appropriately. Patients' most common worries were being dependent on IC for life. In all, 46.9% had incontinence in intervals; 47.9% said IC improved their life quality; and 97.4% preferred IC over continuous catheterization.

  16. Thermal activation of dislocations in large scale obstacle bypass

    Science.gov (United States)

    Sobie, Cameron; Capolungo, Laurent; McDowell, David L.; Martinez, Enrique

    2017-08-01

    Dislocation dynamics simulations have been used extensively to predict hardening caused by dislocation-obstacle interactions, including irradiation defect hardening in the athermal case. Incorporating the role of thermal energy on these interactions is possible with a framework provided by harmonic transition state theory (HTST) enabling direct access to thermally activated reaction rates using the Arrhenius equation, including rates of dislocation-obstacle bypass processes. Moving beyond unit dislocation-defect reactions to a representative environment containing a large number of defects requires coarse-graining the activation energy barriers of a population of obstacles into an effective energy barrier that accurately represents the large scale collective process. The work presented here investigates the relationship between unit dislocation-defect bypass processes and the distribution of activation energy barriers calculated for ensemble bypass processes. A significant difference between these cases is observed, which is attributed to the inherent cooperative nature of dislocation bypass processes. In addition to the dislocation-defect interaction, the morphology of the dislocation segments pinned to the defects play an important role on the activation energies for bypass. A phenomenological model for activation energy stress dependence is shown to describe well the effect of a distribution of activation energies, and a probabilistic activation energy model incorporating the stress distribution in a material is presented.

  17. Visualizing news: obstacles, challenges, and solutions

    NARCIS (Netherlands)

    Smit, Gerard; Haan, Yael de; Buijs, Laura; Bakker, Piet

    2013-01-01

    Depicting news graphically is considered an apt way to deal with challenges of modern journalism: to disclose big data, and present news attractively, visually, and fast to grasp. This study delves into reported obstacles and challenges for the production of news visualizations. It focuses on the qu

  18. An Obstacle Problem for Noncoercive Operators

    Directory of Open Access Journals (Sweden)

    Luigi Greco

    2015-01-01

    Full Text Available We study the obstacle problem for second order nonlinear equations whose model appears in the stationary diffusion-convection problem. We assume that the growth coefficient of the convection term lies in the Marcinkiewicz space weak-LN.

  19. Simple Obstacle Avoidance Algorithm for Rehabilitation Robots

    NARCIS (Netherlands)

    Stuyt, F.H.A.; Römer, G.R.B.; Stuyt, H.J.A.

    2007-01-01

    The efficiency of a rehabilitation robot is improved by offering record-and-replay to operate the robot. While automatically moving to a stored target (replay) collisions of the robot with obstacles in its work space must be avoided. A simple, though effective, generic and deterministic algorithm fo

  20. Transport in active systems crowded by obstacles

    Science.gov (United States)

    Huang, Mu-Jie; Schofield, Jeremy; Kapral, Raymond

    2017-02-01

    The reactive and diffusive dynamics of a single chemically powered Janus motor in a crowded medium of moving but passive obstacles is investigated using molecular simulation. It is found that the reaction rate of the catalytic motor reaction decreases in a crowded medium as the volume fraction of obstacles increases as a result of a reduction in the Smoluchowski diffusion-controlled reaction rate coefficient that contributes to the overall reaction rate. A continuum model is constructed and analyzed to interpret the dependence of the steady-state reaction rate observed in simulations on the volume fraction of obstacles in the system. The steady-state concentration fields of reactant and product are shown to be sensitive to the local structure of obstacles around the Janus motor. It is demonstrated that the active motor exhibits enhanced diffusive motion at long times with a diffusion constant that decreases as the volume fraction of crowding species increases. In addition, the dynamical properties of a passive tracer particle in a system containing many active Janus motors is studied to investigate how an active environment influences the transport of non-active species. The diffusivity of a passive tracer particle in an active medium is found to be enhanced in systems with forward-moving Janus motors due to the cooperative dynamics of these motors.

  1. The Obstacles in Cross-cultural Communication

    Institute of Scientific and Technical Information of China (English)

    WANG Jian-hua

    2009-01-01

    In Cross-cultural communication,the ability of the languages and the ability of the cultures ale the crucial factors in the communicating activities.People with the sanle cultural background communicate with each other easily and smoothly,and understand each other better,and there are fewer or no obstacles in their communication at all.The different cultural backgrounds and traditions,the different social customs and everyday living habits,and the different values all will affect the communication quality and will surely result in obstacles in cross-cultural communication.The obstacles which frequently occur in the cross-cultural communication are:ethnocentrism,stereotyping,prejudice,and the different cultural backgrounds.In order to do away with the obstacles and to make the communication smoothly and successfully,the communicating parties both should observe the cooperative principles and politeness principles.And what's more,they must discard their own prejudices,and respect others,together to fulfill the cross-cultural communicating activities.

  2. The business of medicine: how to overcome financial obstacles and secure financing for your private practice and ancillary services business.

    Science.gov (United States)

    Nayor, David

    2012-01-01

    Doctors across the country who operate private medical practices are facing increasing financial obstacles, namely shrinking income as a result of rising costs and lower reimbursements. In addition, as hospitals have become overburdened many physicians have opened up private surgical centers; magnetic resonance imaging and computed tomography and positron emission tomography scanning facilities; pathology labs; colonoscopy/endoscopy suites; lithotripsy centers; and other medical businesses typically performed within the hospital. Moreover, many doctors seek loans to purchase existing practices or for their capital contribution in medical partnerships. The past decade has thus seen a significant increase in the number of doctors taking out small business loans. Indeed, banks view the healthcare industry as a large growth market. This article includes practical information, advice, and resources to help doctors to secure bank financing for their practices, ancillary services business, real estate, and equipment on the best possible market terms.

  3. Fast obstacle detection based on multi-sensor information fusion

    Science.gov (United States)

    Lu, Linli; Ying, Jie

    2014-11-01

    Obstacle detection is one of the key problems in areas such as driving assistance and mobile robot navigation, which cannot meet the actual demand by using a single sensor. A method is proposed to realize the real-time access to the information of the obstacle in front of the robot and calculating the real size of the obstacle area according to the mechanism of the triangle similarity in process of imaging by fusing datum from a camera and an ultrasonic sensor, which supports the local path planning decision. In the part of image analyzing, the obstacle detection region is limited according to complementary principle. We chose ultrasonic detection range as the region for obstacle detection when the obstacle is relatively near the robot, and the travelling road area in front of the robot is the region for a relatively-long-distance detection. The obstacle detection algorithm is adapted from a powerful background subtraction algorithm ViBe: Visual Background Extractor. We extracted an obstacle free region in front of the robot in the initial frame, this region provided a reference sample set of gray scale value for obstacle detection. Experiments of detecting different obstacles at different distances respectively, give the accuracy of the obstacle detection and the error percentage between the calculated size and the actual size of the detected obstacle. Experimental results show that the detection scheme can effectively detect obstacles in front of the robot and provide size of the obstacle with relatively high dimensional accuracy.

  4. Priming with threatening faces modulates the self-face advantage by enhancing the other-face processing rather than suppressing the self-face processing.

    Science.gov (United States)

    Guan, Lili; Qi, Mingming; Li, Haijiang; Hitchman, Glenn; Yang, Juan; Liu, Yijun

    2015-05-22

    Social emotional information influences self-processing in everyday activities, but few researchers have investigated this process. The current ERP study adopted a prime paradigm to investigate how socially threatening faces impact on the self-face processing advantage. After being primed with emotional faces (happy, angry or neutral), participants judged whether the target face (self, friend, and stranger) was familiar or unfamiliar. Results showed an interaction effect between the prime face and the target face at posterior P3, suggesting that after priming with happy and neutral faces, self-faces elicited larger P3 amplitudes than friend-faces and stranger-faces; however, after priming with angry faces, the P3 amplitudes were not significantly different between self-face and friend-face. Moreover, the P3 amplitudes of self-faces did not differ between priming with angry and neutral faces; however, the P3 amplitude of both friend-faces and stranger-faces showed enhanced responses after priming with angry faces compared to priming with neutral faces. We suggest that the self-face processing advantage (self vs. friend) could be weakened by priming with threatening faces, through enhancement of the other-faces processing rather than suppression of self-faces processing in angry vs. neutral face prime.

  5. A PSO-Optimized Reciprocal Velocity Obstacles Algorithm for Navigation of Multiple Mobile Robots

    OpenAIRE

    Ziyad Allawi; Turki Abdalla

    2015-01-01

    In this paper, a new optimization method for the Reciprocal Velocity Obstacles (RVO) is proposed. It uses the well-known Particle Swarm Optimization (PSO) for navigation control of multiple mobile robots with kinematic constraints. The RVO is used for collision avoidance between the robots, while PSO is used to choose the best path for the robot maneuver to avoid colliding with other robots and to get to its goal faster. This method was applied on 24 mobile robots facing each other. Simulatio...

  6. About Face

    Medline Plus

    Full Text Available ... PTSD (posttraumatic stress disorder). Watch the intro This is AboutFace In these videos, Veterans, family members, and ... to hear what they have to say. What is PTSD? → How does PTSD affect loved ones? → Am ...

  7. About Face

    Medline Plus

    Full Text Available ... traumatic event — like combat, an assault, or a disaster — it's normal to feel scared, keyed up, or sad at first. But if it's been months or years since the trauma and you're not feeling better, you may have PTSD (posttraumatic stress disorder). Watch the intro This is AboutFace In ...

  8. 2D Hand Tracking Based on Flocking with Obstacle Avoidance

    Directory of Open Access Journals (Sweden)

    Zihong Chen

    2014-02-01

    Full Text Available Hand gesture-based interaction provides a natural and powerful means for human-computer interaction. It is also a good interface for human-robot interaction. However, most of the existing proposals are likely to fail when they meet some skin-coloured objects, especially the face region. In this paper, we present a novel hand tracking method which can track the features of the hand based on the obstacle avoidance flocking behaviour model to overcome skin-coloured distractions. It allows features to be split into two groups under severe distractions and merge later. The experiment results show that our method can track the hand in a cluttered background or when passing the face, while the Flocking of Features (FoF and the Mean Shift Embedded Particle Filter (MSEPF methods may fail. These results suggest that our method has better performance in comparison with the previous methods. It may therefore be helpful to promote the use of the hand gesture-based human-robot interaction method.

  9. 2D Hand Tracking Based on Flocking with Obstacle Avoidance

    Directory of Open Access Journals (Sweden)

    Zihong Chen

    2014-02-01

    Full Text Available Hand gesture-based interaction provides a natural and powerful means for human-computer interaction. It is also a good interface for human-robot interaction. However, most of the existing proposals are likely to fail when they meet some skin-coloured objects, especially the face region. In this paper, we present a novel hand tracking method which can track the features of the hand based on the obstacle avoidance flocking behaviour model to overcome skin-coloured distractions. It allows features to be split into two groups under severe distractions and merge later. The experiment results show that our method can track the hand in a cluttered background or when passing the face, while the Flocking of Features (FoF and the Mean Shift Embedded Particle Filter (MSEPF methods may fail. These results suggest that our method has better performance in comparison with the previous methods. It may therefore be helpful to promote the use of the hand gesture-based human-robot interaction method.

  10. Getting stuck or stepping back: effects of obstacles and construal level in the negotiation of creative solutions

    NARCIS (Netherlands)

    C.K.W. de Dreu; M. Giacomantonio; S. Shalvi; D.J. Sligte

    2009-01-01

    Difficult issues in negotiation act as interfering forces but their effects on negotiation processes and outcomes are unclear. Perhaps facing such obstacles leads individuals to take a step back, attend to the big picture and, therefore, to be able to craft creative, mutually beneficial solutions. A

  11. A Different Kind of Smart: A Study of the Educational Obstacles Confronting Homeless Youth in New England.

    Science.gov (United States)

    Wilson, Melanie; Houghton, Alison

    This study provides information on obstacles facing homeless youth in school. Research occurred in four diverse New England cities. Researchers collected detailed case histories on youth age 10-15 years who were currently homeless or who had recently been homeless. Data came from staff of local youth agencies, government officials, and youths…

  12. Group Work and the Change of Obstacles over Time: The Influence of Learning Style and Group Composition

    Science.gov (United States)

    Soetanto, Danny; MacDonald, Matthew

    2017-01-01

    It is through working in groups that students develop cooperative learning skills and experience. However, group work activity often leads students into a difficult experience, especially for first-year students who are not familiar with group work activities at university. This study explores obstacles faced by first-year students during their…

  13. Getting stuck or stepping back: effects of obstacles and construal level in the negotiation of creative solutions

    NARCIS (Netherlands)

    de Dreu, C.K.W.; Giacomantonio, M.; Shalvi, S.; Sligte, D.J.

    2009-01-01

    Difficult issues in negotiation act as interfering forces but their effects on negotiation processes and outcomes are unclear. Perhaps facing such obstacles leads individuals to take a step back, attend to the big picture and, therefore, to be able to craft creative, mutually beneficial solutions.

  14. Nonholonomic feedback control among moving obstacles

    Science.gov (United States)

    Armstrong, Stephen Gregory

    A feedback controller is developed for navigating a nonholonomic vehicle in an area with multiple stationary and possibly moving obstacles. Among other applications the developed algorithms can be used for automatic parking of a passenger car in a parking lot with complex configuration or a ground robot in cluttered environment. Several approaches are explored which combine nonholonomic systems control based on sliding modes and potential field methods.

  15. Reading faces and Facing words

    DEFF Research Database (Denmark)

    Robotham, Julia Emma; Lindegaard, Martin Weis; Delfi, Tzvetelina Shentova

    It has long been argued that perceptual processing of faces and words is largely independent, highly specialised and strongly lateralised. Studies of patients with either pure alexia or prosopagnosia have strongly contributed to this view. The aim of our study was to investigate how visual...

  16. Reading faces and Facing words

    DEFF Research Database (Denmark)

    Robotham, Julia Emma; Lindegaard, Martin Weis; Delfi, Tzvetelina Shentova

    performed within normal range on at least one test of visual categorisation, strongly suggesting that their abnormal performance with words and faces does not represent a generalised visuo-perceptual deficit. Our results suggest that posterior areas in both hemispheres may be critical for both reading...

  17. The Major Obstacles in Improving English Reading Speed

    Institute of Scientific and Technical Information of China (English)

    任政谦

    2012-01-01

    This thesis analyzes the major obstacles in improving English reading speed,such as being lack of vocabulary and grammatical knowledge,bad reading habits,being lack of reading interest and the obstacle of cultural background knowledge,etc.Through discussing those major obstacles,this thesis puts forward some suggestions and teaching strategies.Those suggestions and teaching strategies will help college students to overcome the major obstacles and improve English reading speed.

  18. WOAH: an obstacle avoidance technique for high speed path following

    Science.gov (United States)

    Tuck, Nat; McGuinness, Michael; Martin, Fred

    2011-01-01

    This paper presents WOAH, a method for real-time mobile robot path following and obstacle avoidance. WOAH provides reactive speed and turn instructions based on obstacle information sensed by a laser range finder. Unlike many previous techniques, this method allows a robot to move quickly past obstacles that are not directly in its path, avoiding slowdowns in path following encountered by previous obstacle avoidance techniques.

  19. Dynamic Obstacle Avoidance for an Omnidirectional Mobile Robot

    OpenAIRE

    Williams, Robert L.; Jianhua Wu

    2010-01-01

    We have established a novel method of obstacle-avoidance motion planning for mobile robots in dynamic environments, wherein the obstacles are moving with general velocities and accelerations, and their motion profiles are not preknown. A hybrid system is presented in which a global deliberate approach is applied to determine the motion in the desired path line (DPL), and a local reactive approach is used for moving obstacle avoidance. A machine vision system is required to sense obstacle moti...

  20. Autonomous obstacle detection and avoidance techniques for lunar lander

    Science.gov (United States)

    Li, Shuang; Peng, Yuming

    Autonomous obstacle detection and avoidance (AODA) techniques is prerequisite for future pinpoint lunar landing missions. Information weighted fusion hazard detection algorithms are firstly proposed to improve the success probability of obstacle detection. Secondly, guidance law for constant-thrust engine is designed to avoid the detected obstacles and steer the lander to the safe landing site. Finally, the validity of the proposed obstacle detection and avoidance techniques are confirmed by computer simulation.

  1. Quantified Faces

    DEFF Research Database (Denmark)

    Sørensen, Mette-Marie Zacher

    2016-01-01

    Abstract: The article presents three contemporary art projects that, in various ways, thematise questions regarding numerical representation of the human face in relation to the identification of faces, for example through the use of biometric video analysis software, or DNA technology. The Dutch...... and critically examine bias in surveillance technologies, as well as scientific investigations, regarding the stereotyping mode of the human gaze. The American artist Heather Dewey-Hagborg creates three-dimensional portraits of persons she has “identified” from their garbage. Her project from 2013 entitled....... The three works are analysed with perspectives to historical physiognomy and Francis Galton's composite portraits from the 1800s. It is argued that, rather than being a statistical compression like the historical composites, contemporary statistical visual portraits (composites) are irreversible...

  2. The Obstacles in Learning English of English Majors

    Institute of Scientific and Technical Information of China (English)

    陈树琴

    2015-01-01

    In recent years,more and more foreign language researchers have taken the obstacle factors into consideration. Among the obstacle factors influencing language learning,anxiety ranks high.This paper focuses on the obstacle factors analysis and the way to reduce the negative effects they cause.

  3. The Obstacles in Learning English of English Majors

    Institute of Scientific and Technical Information of China (English)

    陈树琴

    2015-01-01

    In recent years,more and more foreign language researchers have taken the obstacle factors into consideration.Among the obstacle factors influencing language learning,anxiety ranks high.This paper focuses on the obstacle factors analysis and the way to reduce the negative effects they cause.

  4. Characteristics of leading forelimb movements for obstacle avoidance during locomotion in rats.

    Science.gov (United States)

    Aoki, Sho; Sato, Yamato; Yanagihara, Dai

    2012-10-01

    Walking smoothly and safely often involves stepping over an obstacle. The purpose of this study was to examine forelimb movements and toe trajectories in stepping over an obstacle during overground locomotion in rats. We performed a kinematic analysis of forelimb movements and measured electromyographic (EMG) activities in the biceps and triceps brachii of the forelimbs. We found that mean toe height just above the obstacle was lower in the leading forelimb than in the trailing forelimb. The toe positions of the leading forelimb at maximal elevation over the obstacle (peak toe position) were closer to the upper edge of the obstacle than those of the trailing forelimb. The linear distance between peak toe position and the upper edge of the obstacle was significantly less in the leading forelimb compared to the trailing forelimb. The peak toe position of the leading forelimb spatially corresponds to the transition point from flexion to extension of the elbow joint. This transition appeared to be controlled mainly by an offset of EMG activity of the elbow flexor, the biceps brachii muscle. In contrast, the trailing forelimb appeared to be controlled by the shoulder and wrist joints. These results suggest that the toe trajectory of the leading forelimb is more accurately regulated than that of the trailing forelimb. In addition, the activities of the elbow flexor may in part contribute to the toe trajectory of the leading forelimb. Copyright © 2012 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

  5. Intact automatic avoidance of obstacles in patients with visual form agnosia.

    Science.gov (United States)

    Rice, Nichola J; McIntosh, Robert D; Schindler, Igor; Mon-Williams, Mark; Démonet, Jean-François; Milner, A David

    2006-09-01

    In everyday life our reaching behaviour has to be guided not only by the location and properties of the target object, but also by the presence of potential obstacles in the workspace. Recent evidence from neglect and optic ataxia patients has suggested that this automatic obstacle avoidance is mediated by the dorsal, rather than the ventral, stream of visual processing. We tested this idea in two studies involving patients with visual form agnosia resulting from bilateral ventral-stream damage. In the first study, we asked patient DF to reach out and pick up a target object in the presence of obstacles placed at varying distances to the left or right of the target. We found that both DF and controls shifted their trajectories away from the potential obstacles and adjusted their grip aperture in such a way as to minimize risk of collision. In a second study, we asked DF and a second patient, SB, to either reach between, or to bisect the space between, two cylinders presented at varying locations. We found that both patients adjusted their reach trajectories to account for shifts in cylinder location in the reaching task, despite showing significantly worse performance than control subjects when asked to make a bisection judgement. Taken together, these data indicate that automatic obstacle avoidance behaviour is spared in our patients with visual form agnosia. We attribute their ability to the functional intactness of the dorsal stream of visual processing, and argue that the ventral stream plays no important role in automatic obstacle avoidance.

  6. Control of vertical posture while elevating one foot to avoid a real or virtual obstacle.

    Science.gov (United States)

    Ida, Hirofumi; Mohapatra, Sambit; Aruin, Alexander

    2017-06-01

    The purpose of this study is to investigate the control of vertical posture during obstacle avoidance in a real versus a virtual reality (VR) environment. Ten healthy participants stood upright and lifted one leg to avoid colliding with a real obstacle sliding on the floor toward a participant and with its virtual image. Virtual obstacles were delivered by a head mounted display (HMD) or a 3D projector. The acceleration of the foot, center of pressure, and electrical activity of the leg and trunk muscles were measured and analyzed during the time intervals typical for early postural adjustments (EPAs), anticipatory postural adjustments (APAs), and compensatory postural adjustments (CPAs). The results showed that the peak acceleration of foot elevation in the HMD condition decreased significantly when compared with that of the real and 3D projector conditions. Reduced activity of the leg and trunk muscles was seen when dealing with virtual obstacles (HMD and 3D projector) as compared with that seen when dealing with real obstacles. These effects were more pronounced during APAs and CPAs. The onsets of muscle activities in the supporting limb were seen during EPAs and APAs. The observed modulation of muscle activity and altered patterns of movement seen while avoiding a virtual obstacle should be considered when designing virtual rehabilitation protocols.

  7. Sociodemographic factors associated with obstacles to abortion care: findings from a survey of abortion patients in Mexico City.

    Science.gov (United States)

    Becker, Davida; Diaz-Olavarrieta, Claudia; Juarez, Clara; Garcia, Sandra G; Sanhueza Smith, Patricio; Harper, Cynthia C

    2011-01-01

    First-trimester abortion was legalized in Mexico City in 2007, and services are now provided at public and private sites throughout the city. However, little is known about the obstacles women face when seeking abortion care. We surveyed women who obtained abortion services (n = 398) at three public sector facilities in Mexico City to identify the obstacles women faced when obtaining abortions. We used logistic regression to test whether obstacles varied by sociodemographic characteristics. Women with low education were more likely than high school-educated women to report difficulty getting appointments. Unmarried women and women with low education were more likely than married women or high school educated women to report difficulty getting time off work for appointments and arranging for transportation to the facility. Separated or divorced women were more likely than married women to report partner or other family member opposition to the abortion. Women who lived outside of Mexico City were more likely than Mexico City residents to report difficulty with transportation. Education, marital status, and place of residence were associated with the obstacles women reported. Strategies to improve access to care should be targeted to the groups at highest risk of experiencing obstacles: Women with primary education or lower, single women, separated/divorced women, and those residing outside of Mexico City. Copyright © 2011 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

  8. Dynamic clearance measure to evaluate locomotor and perceptuo-motor strategies used for obstacle circumvention in a virtual environment.

    Science.gov (United States)

    Darekar, Anuja; Lamontagne, Anouk; Fung, Joyce

    2015-04-01

    Circumvention around an obstacle entails a dynamic interaction with the obstacle to maintain a safe clearance. We used a novel mathematical interpolation method based on the modified Shepard's method of Inverse Distance Weighting to compute dynamic clearance that reflected this interaction as well as minimal clearance. This proof-of-principle study included seven young healthy, four post-stroke and four healthy age-matched individuals. A virtual environment designed to assess obstacle circumvention was used to administer a locomotor (walking) and a perceptuo-motor (navigation with a joystick) task. In both tasks, participants were asked to navigate towards a target while avoiding collision with a moving obstacle that approached from either head-on, or 30° left or right. Among young individuals, dynamic clearance did not differ significantly between obstacle approach directions in both tasks. Post-stroke individuals maintained larger and smaller dynamic clearance during the locomotor and the perceptuo-motor task respectively as compared to age-matched controls. Dynamic clearance was larger than minimal distance from the obstacle irrespective of the group, task and obstacle approach direction. Also, in contrast to minimal distance, dynamic clearance can respond differently to different avoidance behaviors. Such a measure can be beneficial in contrasting obstacle avoidance behaviors in different populations with mobility problems.

  9. Face Search at Scale.

    Science.gov (United States)

    Wang, Dayong; Otto, Charles; Jain, Anil K

    2016-06-20

    rsons of interest among the billions of shared photos on these websites. Despite significant progress in face recognition, searching a large collection of unconstrained face images remains a difficult problem. To address this challenge, we propose a face search system which combines a fast search procedure, coupled with a state-of-the-art commercial off the shelf (COTS) matcher, in a cascaded framework. Given a probe face, we first filter the large gallery of photos to find the top-k most similar faces using features learned by a convolutional neural network. The k retrieved candidates are re-ranked by combining similarities based on deep features and those output by the COTS matcher. We evaluate the proposed face search system on a gallery containing 80 million web-downloaded face images. Experimental results demonstrate that while the deep features perform worse than the COTS matcher on a mugshot dataset (93.7% vs. 98.6% TAR@FAR of 0.01%), fusing the deep features with the COTS matcher improves the overall performance (99.5% TAR@FAR of 0.01%). This shows that the learned deep features provide complementary information over representations used in state-of-the-art face matchers. On the unconstrained face image benchmarks, the performance of the learned deep features is competitive with reported accuracies. LFW database: 98.20% accuracy under the standard protocol and 88.03% TAR@FAR of 0.1% under the BLUFR protocol; IJB-A benchmark: 51.0% TAR@FAR of 0.1% (verification), rank 1 retrieval of 82.2% (closed-set search), 61.5% FNIR@FAR of 1% (open-set search). The proposed face search system offers an excellent trade-off between accuracy and scalability on galleries with millions of images. Additionally, in a face search experiment involving photos of the Tsarnaev brothers, convicted of the Boston Marathon bombing, the proposed cascade face search system could find the younger brother's (Dzhokhar Tsarnaev) photo at rank 1 in 1 second on a 5M gallery and at rank 8 in 7

  10. The Influence of Topographic Obstacles on Basaltic Lava Flow Morphologies

    Science.gov (United States)

    von Meerscheidt, H. C.; Brand, B. D.; deWet, A. P.; Bleacher, J. E.; Hamilton, C. W.; Samuels, R.

    2014-12-01

    Smooth pāhoehoe and jagged ´áā represent two end-members of a textural spectrum that reflects the emplacement characteristics of basaltic lava flows. However, many additional textures (e.g., rubbly and slabby pāhoehoe) reflect a range of different process due to lava flow dynamics or interaction with topography. Unfortunately the influence of topography on the distribution of textures in basaltic lava flows is not well-understood. The 18 ± 1.0 ka Twin Craters lava flow in the Zuni-Bandera field (New Mexico, USA) provides an excellent site to study the morphological changes of a lava flow that encountered topographic obstacles. The flow field is 0.2-3.8 km wide with a prominent central tube system that intersects and wraps around a 1000 m long ridge, oriented perpendicular to flow. Upstream of the ridge, the flow has low-relief inflation features extending out and around the ridge. This area includes mildly to heavily disrupted pāhoehoe with interdispersed agglutinated masses, irregularly shaped rubble and lava balls. Breakouts of ´áā and collapse features are also common. These observations suggest crustal disruption due to flow-thickening upstream from the ridge and the movement of lava out and around the obstacle. While the ridge influenced the path of the tube, which wraps around the southern end of the ridge, the series of collapse features and breakouts of ´áā along the tube system are more likely a result of changes in flux throughout the tube system because these features are found both upstream and downstream of the obstacle. This work demonstrates that topography can significantly influence the formation history and surface disruption of a flow field, and in some cases the influence of topography can be separated from the influences of changes in flux along a tube system.

  11. Obstacles and challenges following the partial decriminalisation of abortion in Colombia.

    Science.gov (United States)

    Amado, Eduardo Díaz; Calderón García, Maria Cristina; Cristancho, Katherine Romero; Salas, Elena Prada; Hauzeur, Eliane Barreto

    2010-11-01

    During a highly contested process, abortion was partially decriminalised in Colombia in 2006 by the Constitutional Court: when the pregnancy threatens a woman's life or health, in cases of severe fetal malformations incompatible with life, and in cases of rape, incest or unwanted insemination. However, Colombian women still face obstacles to accessing abortion services. This is illustrated by 36 cases of women who in 2006-08 were denied the right to a lawful termination of pregnancy, or had unjustified obstacles put in their path which delayed the termination, which are analysed in this article. We argue that the obstacles resulted from fundamental disagreements about abortion and misunderstandings regarding the ethical, legal and medical requirements arising from the Court's decision. In order to avoid obstacles such as demands for a judge's authorisation, institutional claims of conscientious objection, rejection of a claim of rape, or refusal of health insurance coverage for a legal termination, which constitute discrimination against women, three main strategies are suggested: public ownership of the Court's decision by all Colombian citizens, a professional approach by those involved in the provision of services in line with the law, and monitoring of its implementation by governmental and non-governmental organisations.

  12. Investigation of administrative obstacles to family physician program in urban areas of Iran

    Directory of Open Access Journals (Sweden)

    Javad Javan noughabi

    2017-06-01

    Full Text Available Health is regarded as one of the basic rights of each person in society; so governments are obligated to provide it equally for everyone. The best way to achieve this goal is the establishment of health insurance with the orientation of family physician and the strategic referral system. Yet, such programs will not be successful without encouraging people to participate and changing social behaviors. The aim of the present study was to investigate the administrative obstacles and problems to family physician program in urban areas of Iran. This study was a qualitative research conducted. A purposive sampling method was employed and the data were gathered via semi-structured interview with open-ended questions and document examination. All the interviews were recorded digitally and immediately transcribed verbatim. They were finally analyzed based on framework analysis. The participants' detailed descriptions showed that systemic, environmental, and human related factors were the main obstacles to the implementation of family physician plan. Since the success and performance of each program effectively cannot be obtained without people’s acceptance and collaboration, the necessity of training and giving information rapidly and timely to the residents in urban areas is felt more than ever. Also, making authorities aware of the obstacles expressed by people can be helpful in harmonizing the program with people’s requests; and can result in overcoming the challenges and obstacles facing the program.

  13. Recognition and Measurement Obstacles of the Conceptual Framework of Financial Accounting Underlying E-commerce Business

    Directory of Open Access Journals (Sweden)

    Sana’a NM

    2016-04-01

    Full Text Available The remarkable growth in electronic commerce constitutes another new challenge for the accounting profession in its effort to meet the rapid and continuing revolution of information changes. Therefore, the objective of this study is to investigate the important obstacles facing corporations working in the business of E-commerce. This study also aims to investigate the production of accounting information as related to level three (recognition and measurements of the conceptual framework underlying financial accounting. Therefore, to achieve the primary objectives of this study the researcher has developed a questionnaire that has been distributed to Jordanian external auditors. A total of 77 questionnaires were distributed; however, only 71 questionnaires were suitable for the analysis. A sample t- test was used to test the hypotheses of the study. The main results of the study revealed high arithmetic mean related to the obstacles of the accounting concepts (principles, assumptions, and constraints at level three of the conceptual framework that underlies financial accounting. This requires attention in the preparation of the financial reports of a corporation operating in E-commerce Business. Moreover, the research concludes that the obstacles are connected, interdependent and interrelated with each other. Therefore, the accounting principle obstacles have implications over the application of accounting assumptions and constraints. Consequently, the researcher recommends the need to make changes in the concepts of recognition and measurements in the conceptual framework that underlies financial accounting. This is to ensure the qualitative characteristics of accounting information for E-commerce business corporations.

  14. APPLICATION OF DSM IN OBSTACLE CLEARANCE SURVEYING OF AERODROME

    Directory of Open Access Journals (Sweden)

    X. Qiao

    2016-06-01

    Full Text Available Compared to the wide use of digital elevation model (DEM, digital surface model (DSM receives less attention because that it is composed by not only terrain surface, but also vegetations and man-made objects which are usually regarded as useless information. Nevertheless, these objects are useful for the identification of obstacles around an aerodrome. The primary objective of the study was to determine the applicability of DSM in obstacle clearance surveying of aerodrome. According to the requirements of obstacle clearance surveying at QT airport, aerial and satellite imagery were used to generate DSM, by means of photogrammetry, which was spatially analyzed with the hypothetical 3D obstacle limitation surfaces (OLS to identify the potential obstacles. Field surveying was then carried out to retrieve the accurate horizontal position and height of the obstacles. The results proved that the application of DSM could make considerable improvement in the efficiency of obstacle clearance surveying of aerodrome.

  15. Application of Dsm in Obstacle Clearance Surveying of Aerodrome

    Science.gov (United States)

    Qiao, X.; Lv, S. H.; Li, L. L.; Zhou, X. J.; Wang, H. Y.; Li, D.; Liu, J. Y.

    2016-06-01

    Compared to the wide use of digital elevation model (DEM), digital surface model (DSM) receives less attention because that it is composed by not only terrain surface, but also vegetations and man-made objects which are usually regarded as useless information. Nevertheless, these objects are useful for the identification of obstacles around an aerodrome. The primary objective of the study was to determine the applicability of DSM in obstacle clearance surveying of aerodrome. According to the requirements of obstacle clearance surveying at QT airport, aerial and satellite imagery were used to generate DSM, by means of photogrammetry, which was spatially analyzed with the hypothetical 3D obstacle limitation surfaces (OLS) to identify the potential obstacles. Field surveying was then carried out to retrieve the accurate horizontal position and height of the obstacles. The results proved that the application of DSM could make considerable improvement in the efficiency of obstacle clearance surveying of aerodrome.

  16. Sedimentation control in the reservoirs by using an obstacle

    Indian Academy of Sciences (India)

    Morteza Marosi; Mehdi Ghomeshi; Hamed Sarkardeh

    2015-06-01

    In the present experimental research, effect of different heights of obstacle on turbidity current, to control the sedimentation in a reservoir, was investigated. Experiments were carried out with horizontal and steep bed slopes and different flow conditions. To see the effect of obstacle on concentration of overflow turbidity current, some experiments were carried out without an obstacle. Results showed that concentration of the currents without obstacle reduced exponentially by distance from the entrance gate. More reduction of density and dilution of the currents were observed in the presence of an obstacle, especially with increasing the heights. Increasing height of obstacle also improved their trap efficiency. Moreover, it was concluded that effect of the presence of an obstacle was less intense in a steep bed slope of the reservoir than in a horizontal one.

  17. A Robust Obstacle Avoidance for Service Robot Using Bayesian Approach

    Directory of Open Access Journals (Sweden)

    Widodo Budiharto

    2011-03-01

    Full Text Available The objective of this paper is to propose a robust obstacle avoidance method for service robot in indoor environment. The method for obstacles avoidance uses information about static obstacles on the landmark using edge detection. Speed and direction of people that walks as moving obstacle obtained by single camera using tracking and recognition system and distance measurement using 3 ultrasonic sensors. A new geometrical model and maneuvering method for moving obstacle avoidance introduced and combined with Bayesian approach for state estimation. The obstacle avoidance problem is formulated using decision theory, prior and posterior distribution and loss function to determine an optimal response based on inaccurate sensor data. Algorithms for moving obstacles avoidance method proposed and experiment results implemented to service robot also presented. Various experiments show that our proposed method very fast, robust and successfully implemented to service robot called Srikandi II that equipped with 4 DOF arm robot developed in our laboratory.

  18. Recovering an obstacle using integral equations

    KAUST Repository

    Rundell, William

    2009-05-01

    We consider the inverse problem of recovering the shape, location and surface properties of an object where the surrounding medium is both conductive and homogeneous and we measure Cauchy data on an accessible part of the exterior boundary. It is assumed that the physical situation is modelled by harmonic functions and the boundary condition on the obstacle is one of Dirichlet type. The purpose of this paper is to answer some of the questions raised in a recent paper that introduced a nonlinear integral equation approach for the solution of this type of problem.

  19. 'Face value': new medical imaging software in commercial view.

    Science.gov (United States)

    Coopmans, Catelijne

    2011-04-01

    Based on three ethnographic vignettes describing the engagements of a small start-up company with prospective competitors, partners and customers, this paper shows how commercial considerations are folded into the ways visual images become 'seeable'. When company members mount demonstrations of prototype mammography software, they seek to generate interest but also to protect their intellectual property. Pivotal to these efforts to manage revelation and concealment is the visual interface, which is variously performed as obstacle and ally in the development of a profitable product. Using the concept of 'face value', the paper seeks to develop further insight into contemporary dynamics of seeing and showing by tracing the way techno-visual presentations and commercial considerations become entangled in practice. It also draws attention to the salience and significance of enactments of surface and depth in image-based practices.

  20. FACE RECOGNITION FROM FRONT-VIEW FACE

    Institute of Scientific and Technical Information of China (English)

    WuLifang; ShenLansun

    2003-01-01

    This letter presents a face normalization algorithm based on 2-D face model to rec-ognize faces with variant postures from front-view face.A 2-D face mesh model can be extracted from faces with rotation to left or right and the corresponding front-view mesh model can be estimated according to facial symmetry.Then based on the relationship between the two mesh models,the nrmalized front-view face is formed by gray level mapping.Finally,the face recognition will be finished based on Principal Component Analysis(PCA).Experiments show that better face recognition performance is achieved in this way.

  1. FACE RECOGNITION FROM FRONT-VIEW FACE

    Institute of Scientific and Technical Information of China (English)

    Wu Lifang; Shen Lansun

    2003-01-01

    This letter presents a face normalization algorithm based on 2-D face model to recognize faces with variant postures from front-view face. A 2-D face mesh model can be extracted from faces with rotation to left or right and the corresponding front-view mesh model can be estimated according to the facial symmetry. Then based on the inner relationship between the two mesh models, the normalized front-view face is formed by gray level mapping. Finally, the face recognition will be finished based on Principal Component Analysis (PCA). Experiments show that better face recognition performance is achieved in this way.

  2. Regularity of solutions of obstacle problems

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    LetΩbe a bounded domain ofRnand letDbe aclosedsubset ofΩ.ForΨ∈W1,2(Ω)suchthatΨ0onΩ[1-2],we setKΨ={w∈W01,2(Ω)|wΨonDinthesense ofW1,2(Ω)}.Ifaij(x)=aji(x)(i,j=1,2,…,n)∈L∞(Ω)andλ|ξ|2 aij(x)ξiξj,x∈Ω,ξ∈Rn,(1.1)The obstacle problems are to find a functionu∈KΨwhich mini mizesj(v)=∫ΩaijivjvdxoverKΨ.Main resultsFor the obstacle problems,the following results arewell known,whose proof can be foundin[3]and[4].Lemma 1.1(i)There exists a uniqueΓΨ∈KΨsuchthat∫ΩaijiΓΨjΓΨdx=wi∈nfK∫ΨΩaijiwjwdx.(ii)There exists a unique...

  3. Obstacle courses… nature, recreation, and health abstract

    Directory of Open Access Journals (Sweden)

    María Morera Castro

    2007-07-01

    Full Text Available Obstacle courses are an activity that brings a group of people together, in which teams are organized to navigate an established route during a set period of time, completing tasks (clues, riddles, or challenges to meet a defined goal.  Rules and safety norms are explained to all participants; however, they are not informed of the location of the clues, riddles, or challenges.  The following should be considered when organizing an obstacle course: objective, topic to be developed, location, materials needed, clues, riddles or challenges that may be included, and how to supervise that all teams pass the checkpoints.  Like any other activity with a touch of competitiveness, fair play and respect should be above any interest.  If, for any reason, any of the teams has an emergency, solidarity should prevail, and the activity can be used to teach values.  An adventurous spirit is also essential in this activity.  The desire for the unknown and the new challenges individuals and groups.  This activity helps groups of friends, children, adults, families, etc. share a nice and healthy day together in contact with nature, rescuing concepts such as cooperation, cleverness and, particularly, team work.

  4. Zika virus: Vaccine initiatives and obstacles

    Directory of Open Access Journals (Sweden)

    Reema Mukherjee

    2017-01-01

    Full Text Available Over 130,000 humans in Brazil are infected with Zika virus (ZIKV since March 2015, and presently 29 countries in Americas have reported local autochthonous ZIKV transmission. Besides the associated clinical features, Brazil has also reported a temporal and spatial association of ZIKV with Guillain-Barre syndrome (GBS and Zika fetal syndrome. ZIKV vaccine approaches include purified inactivated virus, nucleic acid-based vaccines (DNA, RNA, live vector vaccines, subunit vaccines, virus-like particle technologies, and live recombinant vaccines similar to the technologies used against other human flaviviruses. At present, 15 commercial entities are involved in the development of ZIKV vaccine. Vaccines developed through different approaches would have their own inherent advantages and disadvantages. The presentation of disease in different populations and lack of clarity on the pathogenesis and complications is the most important obstacle. Second, Zika belongs to a genus that is notorious for the antibody-mediated enhancement of infection, which proved to be a stumbling block during the development of the dengue vaccine. Identifying large naive and yet uninfected at-risk populations may be an obstacle to demonstrating efficacy. Next, the association of Zika with GBS is being researched since the vaccine may have the potential to provoke similar neuropathophysiologic mechanisms. Zika's association with adverse fetal outcomes necessitates that pregnant women and women of childbearing age are considered for evaluating vaccines, which form a vulnerable group for vaccine trials.

  5. Obstacle avoidance and path planning for carrier aircraft launching

    Directory of Open Access Journals (Sweden)

    Wu Yu

    2015-06-01

    Full Text Available Launching safety and efficiency are important indexes to measure the fighting capacity of carrier. The study on path planning for taxi of carrier aircraft launching under actual deck environment is of great significance. In actual deck scheduling, manual command is applied to taxi of carrier aircraft, which has negative effects on the safety of staff and carrier aircraft launching. In consideration of both the safety and efficiency of carrier aircraft launching, the key elements of the problem are abstracted based on the analysis of deck environment, carrier aircraft maneuver performance and task requirements. According to the problem description, the mathematical model is established including various constraints. The carrier aircraft and the obstacles are reasonably simplified as circle and polygons respectively. What’s more, the proposed collision detection model reduces the calculations. Aimed at the features of model, the theory of model predictive control (MPC is applied to the path search. Then a dynamic weight heuristic function is designed and a dynamic multistep optimization algorithm is proposed. Taking the Nimitz-class aircraft carrier as an example, the paths from parking place to catapult are planned, which indicate the rationality of the model and the effectiveness of the algorithm by comparing the planning results under different simulation environments. The main contribution of research is the establishment of obstacle avoidance and path planning model. In addition, it provides the solution of model and technological foundations for comprehensive command and real-time decision-making of the carrier aircraft.

  6. Educational pathways of Black women physicists: Stories of experiencing and overcoming obstacles in life

    Science.gov (United States)

    Rosa, Katemari; Mensah, Felicia Moore

    2016-12-01

    [This paper is part of the Focused Collection on Gender in Physics.] This is an empirical study on the underrepresentation of people of color in scientific careers. Grounded in critical race theory, the paper examines the lived experiences of six Black women physicists and addresses obstacles faced in their career paths and strategies used to overcome these obstacles. Data for this study were collected through semistructured interviews and coded for emergent themes. The findings reveal that college recruitment and funding were fundamental for these women to choose physics over other STEM fields. In addition, Black women experience unique challenges of socialization in STEM, particularly by exclusion of study groups. We suggest physics departments provide a more inclusive environment to support Black women in science.

  7. [Age(ing) and participative neighbourhood development. Obstacles and perspectives for social sustainability].

    Science.gov (United States)

    Heite, E; Rüßler, H; Stiel, J

    2015-07-01

    Ageing urban societies face the challenge of enabling a "good" life for older people in their neighbourhood areas. This article focuses on potential obstacles and required preconditions for processes of neighbourhood development, based on results from the research and development project "Quality of life of older people in their neighbourhood" (LiW). Preconditions and obstacles include political and organizational requirements, differing understandings of participation of local experts, as well as the organization of the process and the access to the process. Furthermore, problems and social conflicts, which have to be dealt with on the local level, are examined. An example for such conflicts are statements of group-focused enmity. The paper aims to point out the significials of such processes as well as potential barriers and limits in order to inform academics as well as practitioners and to contribute to the sustainable integration of participative neighbourhood development.

  8. Biologically-Inspired Adaptive Obstacle Negotiation Behavior of Hexapod Robots

    DEFF Research Database (Denmark)

    Goldschmidt, Dennis; Wörgötter, Florentin; Manoonpong, Poramate

    2014-01-01

    Neurobiological studies have shown that insects are able to adapt leg movements and posture for obstacle negotiation in changing environments. Moreover, the distance to an obstacle where an insect begins to climb is found to be a major parameter for successful obstacle negotiation. Inspired...... by these findings, we present an adaptive neural control mechanism for obstacle negotiation behavior in hexapod robots. It combines locomotion control, backbone joint control, local leg reflexes, and neural learning. While the first three components generate locomotion including walking and climbing, the neural...... learning mechanism allows the robot to adapt its behavior for obstacle negotiation with respect to changing conditions, e.g., variable obstacle heights and different walking gaits. By successfully learning the association of an early, predictive signal (conditioned stimulus, CS) and a late, reflex signal...

  9. EFFECTS OF FLOW INTENSITY, OBSTACLE ALIGNMENT AND CROSS-SECTION GEOMETRY ON SCOUR AT BRIDGE ABUTMENTS

    Institute of Scientific and Technical Information of China (English)

    A. H. CARDOSO; J. S. SANTOS; M. ROCA

    2002-01-01

    Experiments are reported on the effects of flow intensity, obstacle alignment and cross-section geome try on the equilibrium scour depth around abutments. The effect of flow intensity was studied for clear water flow conditions, the obstacle alignment was studied for a wide range of angles of the obstacle with the flow direction, and tests on the cross-section geometry apply only to the case where the abut ment extends into the main channel of a compound cross-section (two-stage channel). The channel bank and flood plain were built up with sand. The hypothesis of zero scour for flow velocities smaller than approximately 50% of the threshold velocity for the beginning of motion in the approaching flow cannot be rejected; maximum scour occurs for obstacles protruding at right angle from the cross-section walls, the reduction being small when obstacles point upstream; compared with rigid banks, the scour depth seems to be significantly reduced when channel bank and flood plain are constituted of alluvial material.

  10. New Results on the Vibrating String with a Continuous Obstacle.

    Science.gov (United States)

    1980-05-01

    give ir paragraph IV a regularity theorem in spaces of bounded variation , in the case of a general concave obstacle. In paragrapn V, we shall consider...inequalities instead of (11). du In the second part, we shall assume that the obstacle is plane, and that an- u, are locally of bounded variation . Then the...of bounded variation . Suppose that u0 and uI satisfy the compatibility condition (22), and that the obstacle is concave. Then for all , the

  11. Directed cell migration in the presence of obstacles

    Directory of Open Access Journals (Sweden)

    Grima Ramon

    2007-01-01

    Full Text Available Abstract Background Chemotactic movement is a common feature of many cells and microscopic organisms. In vivo, chemotactic cells have to follow a chemotactic gradient and simultaneously avoid the numerous obstacles present in their migratory path towards the chemotactic source. It is not clear how cells detect and avoid obstacles, in particular whether they need a specialized biological mechanism to do so. Results We propose that cells can sense the presence of obstacles and avoid them because obstacles interfere with the chemical field. We build a model to test this hypothesis and find that this naturally enables efficient at-a-distance sensing to be achieved with no need for a specific and active obstacle-sensing mechanism. We find that (i the efficiency of obstacle avoidance depends strongly on whether the chemotactic chemical reacts or remains unabsorbed at the obstacle surface. In particular, it is found that chemotactic cells generally avoid absorbing barriers much more easily than non-absorbing ones. (ii The typically low noise in a cell's motion hinders the ability to avoid obstacles. We also derive an expression estimating the typical distance traveled by chemotactic cells in a 3D random distribution of obstacles before capture; this is a measure of the distance over which chemotaxis is viable as a means of directing cells from one point to another in vivo. Conclusion Chemotactic cells, in many cases, can avoid obstacles by simply following the spatially perturbed chemical gradients around obstacles. It is thus unlikely that they have developed specialized mechanisms to cope with environments having low to moderate concentrations of obstacles.

  12. A dynamical system approach to realtime obstacle avoidance

    OpenAIRE

    Khansari-Zadeh, S. M.; Billard, Aude

    2012-01-01

    This paper presents a novel approach to real-time obstacle avoidance based on dynamical systems (DS) that ensures impenetrability of multiple convex shaped objects. The proposed method can be applied to perform obstacle avoidance in Cartesian and Joint spaces and using both autonomous and non-autonomous DS-based controllers. Obstacle avoidance proceeds by modulating the original dynamics of the controller. The modulation is parameterizable and allows to determine a safety margin and to increa...

  13. Writing for publication: overcoming common obstacles.

    Science.gov (United States)

    Dies, R R

    1993-04-01

    This article presents the results of a survey of recent authors in the International Journal of Group Psychotherapy who were asked to identify (a) the three most difficult obstacles they encountered when publishing their first article, (b) three types of resources that were most helpful when preparing their manuscript for publication, and (c) advice they would offer to authors who are planning their first paper for submission to a mental health journal. Common problems in manuscripts submitted for editorial review are also highlighted, based on an analysis of 150 letters mailed to authors whose papers were rejected or accepted pending revision. The goal of the present article is to provide guidelines for how to publish successfully.

  14. Real-Time Obstacle Detection Approach using Stereoscopic Images

    Directory of Open Access Journals (Sweden)

    Nadia Baha

    2014-02-01

    Full Text Available In this paper, we propose a new and simple approach to obstacle and free space detection in an indoor and outdoor environment in real-time using stereo vision as sensor. The real-time obstacle detection algorithm uses two dimensional disparity map to detect obstacles in the scene without constructing the ground plane. The proposed approach combines an accumulating and thresholding techniques to detect and cluster obstacle pixels into objects using a dense disparity map. The results from both analysis modules are combined to provide information of the free space. Experimental results are presented to show the effectiveness of the proposed method in real-time.

  15. Biologically-Inspired Adaptive Obstacle Negotiation Behavior of Hexapod Robots

    DEFF Research Database (Denmark)

    Goldschmidt, Dennis; Wörgötter, Florentin; Manoonpong, Poramate

    2014-01-01

    Neurobiological studies have shown that insects are able to adapt leg movements and posture for obstacle negotiation in changing environments. Moreover, the distance to an obstacle where an insect begins to climb is found to be a major parameter for successful obstacle negotiation. Inspired by th...... transferred to a real hexapod robot, called AMOS II. The results show that the robot can efficiently negotiate obstacles with a height up to 85% of the robot's leg length in simulation and 75% in a real environment....

  16. A neural network based wake model for small wind turbine siting near obstacles

    Science.gov (United States)

    Brunskill, Andrew William

    Many potential small wind turbine locations are near obstacles such as buildings and shelterbelts, which can have a significant, detrimental effect on the local wind climate. This thesis describes the creation of a new model which can predict the wind speed, turbulence intensity, and wind power density at any point in an obstacle's region of influence, relative to unsheltered conditions. Artificial neural networks were used to learn the relationship between an obstacle's characteristics and its effects on the local wind. The neural network was trained using measurements collected in the wakes of scale models exposed to a simulated atmospheric boundary layer in a wind tunnel. A field experiment was conducted to validate the wind tunnel measurements. Model predictions are most accurate in the far wake region. The estimated mean uncertainties associated with model predictions of velocity deficit, power density deficit, and turbulence intensity excess are 5.0%, 15%, and 12.8%, respectively.

  17. Comparative analysis of organizational obstacles to CHP/DH

    Energy Technology Data Exchange (ETDEWEB)

    Ruedig, W.

    1986-04-01

    An explanation is given of the vast differences between the countries of Western Europe in the adoption of combined heat and power (CHP) for district heating (DH). The history of this technology in FR Germany and the UK is analysed in detail, and experiences of other countries are reviewed. It is concluded that the over centralization of the electricity supply industry is a major obstacle in the widespread adoption of combined heat and power and district heating. Significant improvements of energy efficiency would thus require organizational reforms giving greater powers to local energy organizations. This, however, should not imply total decentralization of energy supply. Instead, a two-tier system is proposed in which central organizations remain responsible for bulk supply but where local or regional bodies are in charge of all gas, electricity and heat supplies to the final user.

  18. Visualization of deflagration-to-detonation transitions in a channel with repeated obstacles using a hydrogen-oxygen mixture

    Science.gov (United States)

    Maeda, S.; Minami, S.; Okamoto, D.; Obara, T.

    2016-09-01

    The deflagration-to-detonation transition in a 100 mm square cross-section channel was investigated for a highly reactive stoichiometric hydrogen oxygen mixture at 70 kPa. Obstacles of 5 mm width and 5, 10, and 15 mm heights were equally spaced 60 mm apart at the bottom of the channel. The phenomenon was investigated primarily by time-resolved schlieren visualization from two orthogonal directions using a high-speed video camera. The detonation transition occurred over a remarkably short distance within only three or four repeated obstacles. The global flame speed just before the detonation transition was well below the sound speed of the combustion products and did not reach the sound speed of the initial unreacted gas for tests with an obstacle height of 5 and 10 mm. These results indicate that a detonation transition does not always require global flame acceleration beyond the speed of sound for highly reactive combustible mixtures. A possible mechanism for this detonation initiation was the mixing of the unreacted and reacted gas in the vicinity of the flame front convoluted by the vortex present behind each obstacle, and the formation of a hot spot by the shock wave. The final onset of the detonation originated from the unreacted gas pocket, which was surrounded by the obstacle downstream face and the channel wall.

  19. Smart Sensor Based Obstacle Detection for High-Speed Unmanned Surface Vehicle

    DEFF Research Database (Denmark)

    Hermann, Dan; Galeazzi, Roberto; Andersen, Jens Christian

    2015-01-01

    . A computer vision horizon detector enables a highly accurate attitude estimation despite large and sudden vehicle accelerations. This further facilitates the reduction of sea clutter by utilising a attitude based statistical measure. Full scale sea trials show a significant increase in obstacle tracking...

  20. Major Obstacles Limiting the Development of Bilingual Education in Chinese College

    Science.gov (United States)

    Gu, Tian-shi

    2010-01-01

    Bilingual education is introduced in many Chinese colleges today. A number of studies on bilingual education have been done, but few has significant outcome. From a completely new perspective, the author suggests that there are several major obstacles limiting the development of the new trend, i.e., the limited competent faculty, limited…

  1. Moving Up the Income Ladder? Obstacles to Indigenous Population in Latin America

    Directory of Open Access Journals (Sweden)

    Ivan Grgurić

    2005-12-01

    Full Text Available Latin America is traditionally the region with the highest income and wealth inequality and the indigenous people are the most socially excluded group of the society. The obstacles they face on their way to becoming middle class are numerous. Markets sometimesoperate in an anti-poor way, e.g. capital market imperfections. Next, many Latin American countries are agrarian societies with high land inequality. Also, indigenous people continue to have lower health and education indicators. Possible solutions should include state intervention in providing easier access to credit for the indigenous, land reform, health and education systems that are more universal and better targeting of social transfers.

  2. A PSO-Optimized Reciprocal Velocity Obstacles Algorithm for Navigation of Multiple Mobile Robots

    Directory of Open Access Journals (Sweden)

    Ziyad Allawi

    2015-03-01

    Full Text Available In this paper, a new optimization method for the Reciprocal Velocity Obstacles (RVO is proposed. It uses the well-known Particle Swarm Optimization (PSO for navigation control of multiple mobile robots with kinematic constraints. The RVO is used for collision avoidance between the robots, while PSO is used to choose the best path for the robot maneuver to avoid colliding with other robots and to get to its goal faster. This method was applied on 24 mobile robots facing each other. Simulation results have shown that this method outperforms the ordinary RVO when the path is heuristically chosen.

  3. Malaysia’s First Transplanted Case of Chronic Granulomatous Disease: The Journey of Overcoming Obstacles

    Directory of Open Access Journals (Sweden)

    Intan Hakimah Ismail

    2016-05-01

    Full Text Available The awareness of primary immunodeficiency (PID in Malaysia is still not forthcoming. Certain practical issues such as lack of clinical immunologists and specialized laboratory diagnostic facilities remain to be addressed. However, great efforts taken by passionate clinicians and scientists in the immunology networking have ascertained some prevalence. Despite the limitation, all suspected cases of PID are being properly investigated and competently managed. In this case report we highlighted the obstacles we faced in managing PID patients, particularly preparing for bone marrow transplant. This is the first transplanted case of chronic granulomatous disease in Malaysia, which emphasizes the importance of collaborative work to ensure further morbidities or mortalities are prevented.

  4. Learning to Discriminate Face Views

    Directory of Open Access Journals (Sweden)

    Fang Fang

    2011-05-01

    Full Text Available Although visual feature leaning has been well studied, we still know little about the mechanisms of perceptual learning of complex object. Here, human perceptual learning in discrimination of in-depth orientation of face view was studied using psychophysics, EEG and fMRI. We trained subjects to discriminate face orientations around a face view (i.e. 30° over eight daily sessions, which resulted in a significant improvement in sensitivity to the face view orientation. This improved sensitivity was highly specific to the trained orientation and persisted up to six months. Different from perceptual learning of simple visual features, this orientation-specific learning effect could completely transfer across changes in face size, visual field and face identity. A complete transfer also occurred between two partial face images that were mutually exclusive but constituted a complete face. However, the transfer of the learning effect between upright and inverted faces and between a face and a paperclip object was very weak. Before and after training, we measured EEG and fMRI BOLD signals responding to both the trained and the untrained face views. Analyses of ERPs and induced gamma activity showed that face view discrimination training led to a larger reduction of N170 latency at the left occipital-temporal area and a concurrent larger decrease of induced gamma activity at the left frontal area with the trained face view, compared with the untrained ones. BOLD signal amplitude and MVPA analyses showed that, in face-selective cortical areas, training did not lead to a significant amplitude change, but induced a more reliable spatial pattern of neural activity in the left FFA. These results suggest that the visual system had learned how to compute face orientation from face configural information more accurately and that a large amount of plastic changes took place at a level of higher visual processing where size-, location-, and identity

  5. Getting to Darwin: Obstacles to Accepting Evolution by Natural Selection

    Science.gov (United States)

    Thagard, Paul; Findlay, Scott

    2010-01-01

    Darwin's theory of evolution by natural selection is central to modern biology, but is resisted by many people. This paper discusses the major psychological obstacles to accepting Darwin's theory. Cognitive obstacles to adopting evolution by natural selection include conceptual difficulties, methodological issues, and coherence problems that…

  6. Obstacle detection during day and night conditions using stereo vision

    NARCIS (Netherlands)

    Dubbelman, G.; Mark, W. van der; Heuvel, J.C. van den; Groen, F.C.A.

    2007-01-01

    We have developed a stereo vision based obstacle detection (OD) system that can be used to detect obstacles in off-road terrain during both day and night conditions. In order to acquire enough depth estimates for reliable OD during low visibility conditions, we propose a stereo disparity (depth) est

  7. Biologically-Inspired Adaptive Obstacle Negotiation Behavior of Hexapod Robots

    Directory of Open Access Journals (Sweden)

    Dennis eGoldschmidt

    2014-01-01

    Full Text Available Neurobiological studies have shown that insects are able to adapt leg movements and posture for obstacle negotiation in changing environments. Moreover, the distance to an obstacle where an insect begins to climb is found to be a major parameter for successful obstacle negotiation. Inspired by these findings, we present an adaptive neural control mechanism for obstacle negotiation behavior in hexapod robots. It combines locomotion control, backbone joint control, local leg reflexes, and neural learning. While the first three components generate locomotion including walking and climbing, the neural learning mechanism allows the robot to adapt its behavior for obstacle negotiation with respect to changing conditions, e.g., variable obstacle heights and different walking gaits. By successfully learning the association of an early, predictive signal (conditioned stimulus, CS and a late, reflex signal (unconditioned stimulus, UCS, both provided by ultrasonic sensors at the front of the robot, the robot can autonomously find an appropriate distance from an obstacle to initiate climbing. The adaptive neural control was developed and tested first on a physical robot simulation, and was then successfully transferred to a real hexapod robot, called AMOS II. The results show that the robot can efficiently negotiate obstacles with a height up to 85% of the robot's leg length in simulation and 75% in a real environment.

  8. Beam Coupling Impedances of Obstacles Protruding into Beam Pipe

    CERN Document Server

    Kurennoy, S S

    1997-01-01

    The beam coupling impedances of small obstacles protruding inside the vacuum chamber of an accelerator are calculated at frequencies for which the wavelength is large compared to a typical size of the obstacle. Formulas for a few important particular cases are presented which allow simple practical estimates of the broad-band impedance contributions from such discontinuities.

  9. Getting to Darwin: Obstacles to Accepting Evolution by Natural Selection

    Science.gov (United States)

    Thagard, Paul; Findlay, Scott

    2010-01-01

    Darwin's theory of evolution by natural selection is central to modern biology, but is resisted by many people. This paper discusses the major psychological obstacles to accepting Darwin's theory. Cognitive obstacles to adopting evolution by natural selection include conceptual difficulties, methodological issues, and coherence problems that…

  10. Estimates of roughness parameters for arrays of obstacles

    DEFF Research Database (Denmark)

    Duijm, N.J.

    1999-01-01

    Some methods are evaluated and extended to estimate roughness length and zero plane displacement height for atmospheric flow over arrays of obstacles, typically buildings. It appears that the method proposed by Bottema, with an extension to account for low density obstacle arrays, performs best. ...

  11. Collective strategy for obstacle navigation during cooperative transport by ants.

    Science.gov (United States)

    McCreery, Helen F; Dix, Zachary A; Breed, Michael D; Nagpal, Radhika

    2016-11-01

    Group cohesion and consensus have primarily been studied in the context of discrete decisions, but some group tasks require making serial decisions that build on one another. We examine such collective problem solving by studying obstacle navigation during cooperative transport in ants. In cooperative transport, ants work together to move a large object back to their nest. We blocked cooperative transport groups of Paratrechina longicornis with obstacles of varying complexity, analyzing groups' trajectories to infer what kind of strategy the ants employed. Simple strategies require little information, but more challenging, robust strategies succeed with a wider range of obstacles. We found that transport groups use a stochastic strategy that leads to efficient navigation around simple obstacles, and still succeeds at difficult obstacles. While groups navigating obstacles preferentially move directly toward the nest, they change their behavior over time; the longer the ants are obstructed, the more likely they are to move away from the nest. This increases the chance of finding a path around the obstacle. Groups rapidly changed directions and rarely stalled during navigation, indicating that these ants maintain consensus even when the nest direction is blocked. Although some decisions were aided by the arrival of new ants, at many key points, direction changes were initiated within the group, with no apparent external cause. This ant species is highly effective at navigating complex environments, and implements a flexible strategy that works for both simple and more complex obstacles. © 2016. Published by The Company of Biologists Ltd.

  12. Design and Analysis of Hydraulic Chassis with Obstacle Avoidance Function

    Science.gov (United States)

    Hong, Yingjie; Zhang, Xiang

    2017-07-01

    This article mainly expounds the design of hydraulic system for the hydraulic chassis with obstacle avoidance function. Including the selection of hydraulic motor wheels, hydraulic pump, digital hydraulic cylinder and the matching of engine power. And briefly introduces the principle of obstacle avoidance.

  13. Obstacle crossing with lower visual field restriction: Shifts in strategy

    NARCIS (Netherlands)

    Jansen, S.E.M.; Toet, A.; Werkhoven, P.J.

    2011-01-01

    In this study, the authors investigated how restriction of the vertical viewing angle influences obstacle-crossing behavior. Twelve participants stepped over obstacles of different dimensions while wearing visual-field-restricting goggles. Using full-body motion capture, several kinematic measures w

  14. Stereo based Obstacle Detection with Uncertainty in Rough Terrain

    NARCIS (Netherlands)

    Mark, W. van der; Heuvel, J.C. van den; Groen, F.C.A.

    2007-01-01

    Autonomous robot vehicles that operate in offroad terrain should avoid obstacle hazards. In this paper we present a stereo vision based method that is able to cluster reconstructed terrain points into obstacles by evaluating their relative angles and distances. In our approach, constraints are enfor

  15. Swarm Robotics with Circular Formation Motion Including Obstacles Avoidance

    Directory of Open Access Journals (Sweden)

    Nabil M. Hewahi

    2017-07-01

    Full Text Available The robots science has been developed over the past few years, where robots have become used to accomplish difficult, repetitive or accurate tasks, which are very hard for humans to carry out. In this paper, we propose an algorithm to control the motion of a swarm of robots and make them able to avoid obstacles. The proposed solution is based on forming the robots in circular fashion. A group set of robots consists of multiple groups of robots, each group of robots consists of robots forming a circular shape and each group set is a circular form of robots. The proposed algorithm is concerned with first locating the randomly generated robots in groups and secondly with the swarm robot motion and finally with the swarm obstacle avoidance and swarm reorganization after crossing the obstacle. The proposed algorithm has been simulated with five different obstacles with various numbers of randomly generated robots. The results show that the swarm in the circular form can deal with the obstacles very effectively by passing the obstacles smoothly. The proposed algorithm has been compared with flocking algorithm and it is shown that the circular formation algorithm does not need extensive computation after obstacle avoidance whereas the flocking algorithm needs extensive computation. In addition, the circular formation algorithm maintains every robot in its group after avoiding the obstacles whereas with flocking algorithm does not.

  16. The special status of sad infant faces: age and valence differences in adults' cortical face processing.

    Science.gov (United States)

    Colasante, Tyler; Mossad, Sarah I; Dudek, Joanna; Haley, David W

    2016-12-20

    Understanding the relative and joint prioritization of age- and valence-related face characteristics in adults' cortical face processing remains elusive because these two characteristics have not been manipulated in a single study of neural face processing. We used electroencephalography to investigate adults' P1, N170, P2 and LPP responses to infant and adult faces with happy and sad facial expressions. Viewing infant vs adult faces was associated with significantly larger P1, N170, P2 and LPP responses, with hemisphere and/or participant gender moderating this effect in select cases. Sad faces were associated with significantly larger N170 responses than happy faces. Sad infant faces were associated with significantly larger N170 responses in the right hemisphere than all other combinations of face age and face valence characteristics. We discuss the relative and joint neural prioritization of infant face characteristics and negative facial affect, and their biological value as distinct caregiving and social cues.

  17. The Effect of Tai Chi Chuan on Obstacle Crossing Strategy in Older Adults.

    Science.gov (United States)

    Chang, Yao-Ting; Huang, Chen-Fu; Chang, Jia-Hao

    2015-01-01

    The purpose of this study was to determine the effect of Tai Chi Chuan on the strategies of obstacle-crossing behavior in older adults aged over 65 years. Fifteen Tai Chi group (TCG) participants were compared with 15 general group (GG) participants. Kinematic parameters (by Vicon motion analysis system) and ground reaction forces (by Kistler force plates) were synchronously recorded. A two-way mixed-design ANOVA (α = 0.05) was used to test the effects of the group and the obstacle height. The TCG performed significantly faster stride velocities, longer stride lengths, and shorter stride times than GG while crossing the obstacles. TCG could also produce significantly larger forward ground reaction forces to propel the body and were able to make a significantly greater flexion angle of the hip of the leading leg compared with the GG. It was concluded that the TCG adopted a different strategy with GG to cross the obstacles and completed the crossing behavior more effectively.

  18. Trustworthy-Looking Face Meets Brown Eyes

    OpenAIRE

    Karel Kleisner; Lenka Priplatova; Peter Frost; Jaroslav Flegr

    2013-01-01

    We tested whether eye color influences perception of trustworthiness. Facial photographs of 40 female and 40 male students were rated for perceived trustworthiness. Eye color had a significant effect, the brown-eyed faces being perceived as more trustworthy than the blue-eyed ones. Geometric morphometrics, however, revealed significant correlations between eye color and face shape. Thus, face shape likewise had a significant effect on perceived trustworthiness but only for male faces, the eff...

  19. Silo clogging reduction by placing an obstacle above the outlet

    Science.gov (United States)

    Lozano, C.; Zuriguel, I.; Janda, A.; Garcimartín, A.; Arévalo, R.; Maza, D.

    2013-06-01

    We present an experimental study of the effect that an obstacle above the outlet of a silo has on the clogging probability. Both, the size of the orifice and the obstacle position are varied for a chosen obstacle size and shape. If the position of the obstacle is properly selected the clogging probability can be importantly reduced. Indeed, as the outlet size is increased - and we approach the critical size above which there is not clogging - the obstacle effect is enhanced. For the largest outlet size studied, the clogging probability is reduced by a factor of more than one hundred. We will show, using numerical simulations, that the physical parameter behind the reduction of the silo clogging seems to be the decrease of the vertical pressure at the outlet proximities.

  20. Real-Time Fuzzy Obstacle Avoidance Using Directional Visual Perception

    Institute of Scientific and Technical Information of China (English)

    Huang Guoquan(黄国权); Rad A. B.; Wong Y. K.

    2004-01-01

    This paper presents a novel vision-based obstacle avoidance approach for the Autonomous Mobile Robot (AMR) with a Pan- Tilt-Zoom (PTZ) camera as its only sensing modality. The approach combines the morphological closing operation based on Sobel Edge Detection Operation and the (μ-kσ) thresholding technique to detect obstacles to soften the various lighting and ground floor effects. Both the morphology method and thresholding technique are computationally simple. The processing speed of the algorithm is fast enough to avoid some active obstacles. In addition, this approach takes into account the history obstacle effects on the current state. Fuzzy logic is used to control the behaviors of AMR as it navigates in the environment. All behaviors run concurrently and generate motor response solely based on vision perception. A priority based on subsumption coordinator selects the most appropriate response to direct the AMR away from obstacles. Validation of the proposed approach is done on a Pioneer 1 mobile robot.

  1. Obstacle Avoidance for Unmanned Undersea Vehicle in Unknown Unstructured Environment

    Directory of Open Access Journals (Sweden)

    Zheping Yan

    2013-01-01

    Full Text Available To avoid obstacle in the unknown environment for unmanned undersea vehicle (UUV, an obstacle avoiding system based on improved vector field histogram (VFH is designed. Forward looking sonar is used to detect the environment, and the divisional sonar modal is applied to deal with the measure uncertainty. To adapt to the VFH, rolling occupancy grids are used for the map building, and high accuracy details of local environment are obtained. The threshold is adaptively adjusted by the statistic of obstacles to solve the problem that VFH is sensitive to threshold. To improve the environment adaptability, the hybrid-behaviors strategy is proposed, which selects the optimal avoidance command according to the motion status and environment character. The simulation shows that UUV could avoid the obstacles fast and escape from the U shape obstacles.

  2. Dynamic Obstacle Avoidance for an Omnidirectional Mobile Robot

    Directory of Open Access Journals (Sweden)

    Robert L. Williams

    2010-01-01

    Full Text Available We have established a novel method of obstacle-avoidance motion planning for mobile robots in dynamic environments, wherein the obstacles are moving with general velocities and accelerations, and their motion profiles are not preknown. A hybrid system is presented in which a global deliberate approach is applied to determine the motion in the desired path line (DPL, and a local reactive approach is used for moving obstacle avoidance. A machine vision system is required to sense obstacle motion. Through theoretical analysis, simulation, and experimental validation applied to the Ohio University RoboCup robot, we show the method is effective to avoid collisions with moving obstacles in a dynamic environment.

  3. Motion Planning of Humanoid Robot for Obstacle Negotiation

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The motion planning for obstacle negotiation by humanoid robot BHR-2 through stepping over or stepping on/off the wide and flat obstacle at known locations is presented. In the trajectory generation method, first the constraints of the foot motion parameters which include obstacle dimensions and the distance of obstacle from the humanoid robot is formulated. By varying the values of the constraint parameters, different types of foot motion for different obstacles can be produced. In this method, first the foot trajectory is generated, and then the waist trajectory is computed by using cubic spline interpolation without first calculating the zero moment point (ZMP) trajectory . The dynamic stability during the execution of stepping over and stepping on/off trajectories are ensured by incorporating the ZMP criterion. The effectiveness of the proposed method is confirmed by simulations and experiments on humanoid robot BHR-2.

  4. Obstacle Avoidance Based-Visual Navigation for Micro Aerial Vehicles

    Directory of Open Access Journals (Sweden)

    Wilbert G. Aguilar

    2017-01-01

    Full Text Available This paper describes an obstacle avoidance system for low-cost Unmanned Aerial Vehicles (UAVs using vision as the principal source of information through the monocular onboard camera. For detecting obstacles, the proposed system compares the image obtained in real time from the UAV with a database of obstacles that must be avoided. In our proposal, we include the feature point detector Speeded Up Robust Features (SURF for fast obstacle detection and a control law to avoid them. Furthermore, our research includes a path recovery algorithm. Our method is attractive for compact MAVs in which other sensors will not be implemented. The system was tested in real time on a Micro Aerial Vehicle (MAV, to detect and avoid obstacles in an unknown controlled environment; we compared our approach with related works.

  5. Teaching Improvisation in Elementary General Music: Facing Fears and Fostering Creativity

    Science.gov (United States)

    Whitcomb, Rachel

    2013-01-01

    Improvisation is a vital part of an elementary general music education. While some music teachers successfully include improvisation in music instruction, others have fears and face challenges when attempting improvisational activities in the classroom. This article acknowledges obstacles facing music educators when attempting to incorporate…

  6. A New Standard of Care: Despite Opportunity, Gerontology Programs Face Obstacles

    Science.gov (United States)

    Fernandez, Kim

    2008-01-01

    Across the United States, there is a need for professionals who have expertise caring for aging men and women. Doctors and nurses are among the most sought after. But it is not just clinicians who are needed; a variety of professionals, from housing specialists to social workers and service administrators, also are in high demand. Many of the…

  7. A New Standard of Care: Despite Opportunity, Gerontology Programs Face Obstacles

    Science.gov (United States)

    Fernandez, Kim

    2008-01-01

    Across the United States, there is a need for professionals who have expertise caring for aging men and women. Doctors and nurses are among the most sought after. But it is not just clinicians who are needed; a variety of professionals, from housing specialists to social workers and service administrators, also are in high demand. Many of the…

  8. Obstacles Facing Promoting Tourism for Islamic Landmarks from the Perspective of Tour Operators in Egypt

    OpenAIRE

    2015-01-01

    The UNESCO launched a campaign #unite4heritage in Egypt to defeat extremism and intolerance. The message of such campaigne is peace, dialogue and unity embedded in cultural heritage. As culture and tourism are linked together, such message could be delivered through improving culture heritage tourism in Egypt. Islamic landmarks  are considered as a part of human heritage. Therefore, the purpose of this study is to identify how much tour operators in Egypt include Islamic landmarks in their pr...

  9. Political Influence on Japanese Nuclear and Security Policy: New Forces Face Large Obstacles

    Science.gov (United States)

    2014-02-01

    commentary on the U.S. military presence in Okinawa , the U.S.-Japan alliance, and the Japan Self-Defense Forces. This suggests that if empowered enough...supported and sometimes even led by a strong bureaucracy, with oversight by but also much deference from the broader LDP majority in the Diet . During the...own perspective and from that of its American alliance partner. The DPJ mishandled reorganization plans for U.S. military installations in Okinawa

  10. Obstacles facing the venus radar mapper - The implications of gestalt formation in stereo-radargrammetry

    Science.gov (United States)

    Wildey, R.L.

    1986-01-01

    The question of adapting to radar images the existing hardware that form topographic maps through stereo-photogrammetric models, is examined in principle. Such hardware utilizes a human/ computer hybrid. Although the problem of brightness differentials between corresponding landmarks can be dealt with pseudo-photoclinometrically, the main problem is whether the perspective in a radar image can be conceived to mimic that of a photographic image obtained by a suitably positioned camera. This conception is found to be possible, providing the characteristic relief subtends to a very small angle at the radar and at the fictitious camera. The photogrammetric model parameters must be determined a priori. ?? 1986 D. Reidel Publishing Company.

  11. Holistic face training enhances face processing in developmental prosopagnosia.

    Science.gov (United States)

    DeGutis, Joseph; Cohan, Sarah; Nakayama, Ken

    2014-06-01

    Prosopagnosia has largely been regarded as an untreatable disorder. However, recent case studies using cognitive training have shown that it is possible to enhance face recognition abilities in individuals with developmental prosopagnosia. Our goal was to determine if this approach could be effective in a larger population of developmental prosopagnosics. We trained 24 developmental prosopagnosics using a 3-week online face-training program targeting holistic face processing. Twelve subjects with developmental prosopagnosia were assessed before and after training, and the other 12 were assessed before and after a waiting period, they then performed the training, and were then assessed again. The assessments included measures of front-view face discrimination, face discrimination with view-point changes, measures of holistic face processing, and a 5-day diary to quantify potential real-world improvements. Compared with the waiting period, developmental prosopagnosics showed moderate but significant overall training-related improvements on measures of front-view face discrimination. Those who reached the more difficult levels of training ('better' trainees) showed the strongest improvements in front-view face discrimination and showed significantly increased holistic face processing to the point of being similar to that of unimpaired control subjects. Despite challenges in characterizing developmental prosopagnosics' everyday face recognition and potential biases in self-report, results also showed modest but consistent self-reported diary improvements. In summary, we demonstrate that by using cognitive training that targets holistic processing, it is possible to enhance face perception across a group of developmental prosopagnosics and further suggest that those who improved the most on the training task received the greatest benefits.

  12. Obstacle detection for autonomous navigation : an LDRD final report.

    Energy Technology Data Exchange (ETDEWEB)

    Padilla, Denise D.

    2004-03-01

    This report summarizes the analytical and experimental efforts for the Laboratory Directed Research and Development (LDRD) project entitled 'Obstacle Detection for Autonomous Navigation'. The principal goal of this project was to develop a mathematical framework for obstacle detection. The framework provides a basis for solutions to many complex obstacle detection problems critical to successful autonomous navigation. Another goal of this project was to characterize sensing requirements in terms of physical characteristics of obstacles, vehicles, and terrain. For example, a specific vehicle traveling at a specific velocity over a specific terrain requires a sensor with a certain range of detection, resolution, field-of-view, and sufficient sensitivity to specific obstacle characteristics. In some cases, combinations of sensors were required to distinguish between different hazardous obstacles and benign terrain. In our framework, the problem was posed as a multidimensional, multiple-hypothesis, pattern recognition problem. Features were extracted from selected sensors that allow hazardous obstacles to be distinguished from benign terrain and other types of obstacles. Another unique thrust of this project was to characterize different terrain classes with respect to both positive (e.g., rocks, trees, fences) and negative (e.g., holes, ditches, drop-offs) obstacles. The density of various hazards per square kilometer was statistically quantified for different terrain categories (e.g., high desert, ponderosa forest, and prairie). This quantification reflects the scale, or size, and mobility of different types of vehicles. The tradeoffs between obstacle detection, position location, path planning, and vehicle mobility capabilities were also to be characterized.

  13. Obstacle avoidance locomotor tasks: adaptation, memory and skill transfer.

    Science.gov (United States)

    Kloter, Evelyne; Dietz, Volker

    2012-05-01

    The aim of this study was to explore the neural basis of adaptation, memory and skill transfer during human stepping over obstacles. Whilst walking on a treadmill, subjects had to perform uni- and bilateral obstacle steps. Acoustic feedback information about foot clearance was provided. Non-noxious electrical stimuli were applied to the right tibial nerve during the mid-stance phase of the right leg, i.e. 'prior' to the right or 'during' the left leg swing over the obstacle. The electromyogram (EMG) responses evoked by these stimuli in arm and leg muscles are known to reflect the neural coordination during normal and obstacle steps. The leading and trailing legs rapidly adapted foot clearance during obstacle steps with small further changes when the same obstacle condition was repeated. This adaptation was associated with a corresponding decrease in arm and leg muscle reflex EMG responses. Arm (but not leg) muscle EMG responses were greater when the stimulus was applied 'during' obstacle crossing by the left leg leading compared with stimulation 'prior' to right leg swing over the obstacle. A corresponding difference existed in arm muscle background EMG. The results indicate that, firstly, the somatosensory information gained by the performance and adaptation of uni- and bilateral obstacle stepping becomes transferred to the trailing leg in a context-specific manner. Secondly, EMG activity in arm and leg muscles parallels biomechanical adaptation of foot clearance. Thirdly, a consistently high EMG activity in the arm muscles during swing over the obstacle is required for equilibrium control. Thus, such a precision locomotor task is achieved by a context-specific, coordinated activation of arm and leg muscles for performance and equilibrium control that includes adaptation, memory and skill transfer.

  14. Effects of aging on face identification and holistic face processing.

    Science.gov (United States)

    Konar, Yaroslav; Bennett, Patrick J; Sekuler, Allison B

    2013-08-09

    Several studies have shown that face identification accuracy is lower in older than younger adults. This effect of aging might be due to age differences in holistic processing, which is thought to be an important component of human face processing. Currently, however, there is conflicting evidence as to whether holistic face processing is impaired in older adults. The current study therefore re-examined this issue by measuring response accuracy in a 1-of-4 face identification task and the composite face effect (CFE), a common index of holistic processing, in older adults. Consistent with previous reports, we found that face identification accuracy was lower in older adults than in younger adults tested in the same task. We also found a significant CFE in older adults that was similar in magnitude to the CFE measured in younger subjects with the same task. Finally, we found that there was a significant positive correlation between the CFE and face identification accuracy. This last result differs from the results obtained in a previous study that used the same tasks and which found no evidence of an association between the CFE and face identification accuracy in younger adults. Furthermore, the age difference was found with subtraction-, regression-, and ratio-based estimates of the CFE. The current findings are consistent with previous claims that older adults rely more heavily on holistic processing to identify objects in conditions of limited processing resources.

  15. European cinema: face to face with Hollywood

    NARCIS (Netherlands)

    T. Elsaesser

    2005-01-01

    In the face of renewed competition from Hollywood since the early 1980s and the challenges posed to Europe's national cinemas by the fall of the Wall in 1989, independent filmmaking in Europe has begun to re-invent itself. European Cinema: Face to Face with Hollywood re-assesses the different debate

  16. Finding Hope in the Face-to-Face.

    Science.gov (United States)

    Edgoose, Jennifer Y C; Edgoose, Julian M

    2017-05-01

    What does it mean to look into the face of a patient who looks back? Face-to-face encounters are at the heart of the patient-clinician relationship but their singular significance is often lost amid the demands of today's high-tech, metric-driven health care systems. Using the framework provided by the philosopher and Holocaust survivor Emmanuel Levinas, the authors explore the unique responsibility and potential for hope found only in face-to-face encounters. Revisiting this most fundamental attribute of medicine is likely our greatest chance to reclaim who we are as clinicians and why we do what we do. © 2017 Annals of Family Medicine, Inc.

  17. Advanced Augmented White Cane with obstacle height and distance feedback.

    Science.gov (United States)

    Pyun, Rosali; Kim, Yeongmi; Wespe, Pascal; Gassert, Roger; Schneller, Stefan

    2013-06-01

    The white cane is a widely used mobility aid that helps visually impaired people navigate the surroundings. While it reliably and intuitively extends the detection range of ground-level obstacles and drop-offs to about 1.2 m, it lacks the ability to detect trunk and head-level obstacles. Electronic Travel Aids (ETAs) have been proposed to overcome these limitations, but have found minimal adoption due to limitations such as low information content and low reliability thereof. Although existing ETAs extend the sensing range beyond that of the conventional white cane, most of them do not detect head-level obstacles and drop-offs, nor can they identify the vertical extent of obstacles. Furthermore, some ETAs work independent of the white cane, and thus reliable detection of surface textures and drop-offs is not provided. This paper introduces a novel ETA, the Advanced Augmented White Cane, which detects obstacles at four vertical levels and provides multi-sensory feedback. We evaluated the device in five blindfolded subjects through reaction time measurements following the detection of an obstacle, as well as through the reliability of dropoff detection. The results showed that our aid could help the user successfully detect an obstacle and identify its height, with an average reaction time of 410 msec. Drop-offs were reliably detected with an intraclass correlation > 0.95. This work is a first step towards a low-cost ETA to complement the functionality of the conventional white cane.

  18. Vision Based Obstacle Detection mechanism of a Fixed Wing UAV

    Directory of Open Access Journals (Sweden)

    S.N. Omkar

    2014-03-01

    Full Text Available In this paper we have developed a vision based navigation and obstacle detection mechanism for unmanned aerial vehicles (UAVs which can be used effectively in GPS denied regions as well as in regions where remote controlled UAV navigation is impossible thus making the UAV more versatile and fully autonomous. We used a fixed single onboard video camera on the UAV that extracts images of the environment of a UAV. These images are then processed and detect an obstacle in the path if any. This method is effective in detecting dark as well as light coloured obstacles in the vicinity of the UAV. We developed two algorithms. The first one is to detect the horizon and land in the images extracted from the camera and to detect an obstacle in its path. The second one is specifically to detect a light coloured obstacle in the environment thus making our method more precise. The time taken for processing of the images and generating a result is very small thus this algorithm is also fit to be used in real time applications. These Algorithms are more effective than previously developed in this field because this algorithm does the detection of any obstacle without knowing the size of it beforehand. This algorithm is also capable of detecting light coloured obstacles in the sky which otherwise might be missed by an UAV or even a human pilot sometimes. Thus it makes the navigation more precise.

  19. A stereo vision-based obstacle detection system in vehicles

    Science.gov (United States)

    Huh, Kunsoo; Park, Jaehak; Hwang, Junyeon; Hong, Daegun

    2008-02-01

    Obstacle detection is a crucial issue for driver assistance systems as well as for autonomous vehicle guidance function and it has to be performed with high reliability to avoid any potential collision with the front vehicle. The vision-based obstacle detection systems are regarded promising for this purpose because they require little infrastructure on a highway. However, the feasibility of these systems in passenger car requires accurate and robust sensing performance. In this paper, an obstacle detection system using stereo vision sensors is developed. This system utilizes feature matching, epipoplar constraint and feature aggregation in order to robustly detect the initial corresponding pairs. After the initial detection, the system executes the tracking algorithm for the obstacles. The proposed system can detect a front obstacle, a leading vehicle and a vehicle cutting into the lane. Then, the position parameters of the obstacles and leading vehicles can be obtained. The proposed obstacle detection system is implemented on a passenger car and its performance is verified experimentally.

  20. A Proposal of Predictive Reinforcement Learning Realizing Moving Obstacle Avoidance

    Science.gov (United States)

    Takeda, Masato; Nagao, Tomoharu

    In recent years, researches on autonomous robots in real life have developed. Especially, moving obstacle avoidance is one of the most important tasks for robots. Reinforcement learning is a typical method of action acquisitions of autonomous mobile robots for obstacle avoidance. However, it has been indicated that reinforcement learning has various problems in unknown environment. In order to solve these problems, we propose predictive reinforcement learning for moving obstacle avoidance. In predictive reinforcement learning, our rules are not defined as a pair of actions and states like conventional reinforcement learning. The rules are defined as the transition of the states by robot action between steps. We think that proposed rules enable robots to adapt to unknown environment because these rules are independent from any environment where moving obstacles exist. The robots implemented these rules predict the next state. After this prediction, the robots reinforce its rules by comparing observed states with predicted ones and foresee collisions on obstacles. Then the robots select safer actions. In this paper, we verify the efficiency of our method in several simulations. First, the robot is trained in learning environment where moving obstacles exist. After that, we experiment to verify the ability of adaptation to unknown environments. As a result, the robot acquires moving obstacle avoidance actions.

  1. A Robot Manipulator with Adaptive Fuzzy Controller in Obstacle Avoidance

    Science.gov (United States)

    Sreekumar, Muthuswamy

    2016-07-01

    Building robots and machines to act within a fuzzy environment is a problem featuring complexity and ambiguity. In order to avoid obstacles, or move away from it, the robot has to perform functions such as obstacle identification, finding the location of the obstacle, its velocity, direction of movement, size, shape, and so on. This paper presents about the design, and implementation of an adaptive fuzzy controller designed for a 3 degree of freedom spherical coordinate robotic manipulator interfaced with a microcontroller and an ultrasonic sensor. Distance between the obstacle and the sensor and its time rate are considered as inputs to the controller and how the manipulator to take diversion from its planned trajectory, in order to avoid collision with the obstacle, is treated as output from the controller. The obstacles are identified as stationary or moving objects and accordingly adaptive self tuning is accomplished with three set of linguistic rules. The prototype of the manipulator has been fabricated and tested for collision avoidance by placing stationary and moving obstacles in its planned trajectory. The performance of the adaptive control algorithm is analyzed in MATLAB by generating 3D fuzzy control surfaces.

  2. Synthesis of superheavy nuclei: Obstacles and opportunities

    Directory of Open Access Journals (Sweden)

    Zagrebaev V.I.

    2015-01-01

    Full Text Available There are only 3 methods for the production of heavy and superheavy (SH nuclei, namely, fusion reactions, a sequence of neutron capture and beta(- decay and multinucleon transfer reactions. Low values of the fusion cross sections and very short half-lives of nuclei with Z<120 put obstacles in synthesis of new elements. At the same time, an important area of SH isotopes located between those produced in the cold and hot fusion reactions remains unstudied yet. This gap could be filled in fusion reactions of 48Ca with available lighter isotopes of Pu, Am, and Cm. New neutron-enriched isotopes of SH elements may be produced with the use of a 48Ca beam if a 250Cm target would be prepared. In this case we get a real chance to reach the island of stability owing to a possible beta(+ decay of 291114 and 287112 nuclei formed in this reaction with a cross section of about 0.8 pb. A macroscopic amount of the long-living SH nuclei located at the island of stability may be produced by using the pulsed nuclear reactors of the next generation only if the neutron fluence per pulse will be increased by about three orders of magnitude. Multinucleon transfer processes look quite promising for the production and study of neutron-rich heavy nuclei located in upper part of the nuclear map not reachable by other reaction mechanisms. Reactions with actinide beams and targets are of special interest for synthesis of new neutron-enriched transfermium nuclei and not-yet-known nuclei with closed neutron shell N=126 having the largest impact on the astrophysical r-process. The estimated cross sections for the production of these nuclei allows one to plan such experiments at currently available accelerators.

  3. How Obstacles Perturb Population Fronts and Alter Their Genetic Structure.

    Directory of Open Access Journals (Sweden)

    Wolfram Möbius

    2015-12-01

    Full Text Available As populations spread into new territory, environmental heterogeneities can shape the population front and genetic composition. We focus here on the effects of an important building block of heterogeneous environments, isolated obstacles. With a combination of experiments, theory, and simulation, we show how isolated obstacles both create long-lived distortions of the front shape and amplify the effect of genetic drift. A system of bacteriophage T7 spreading on a spatially heterogeneous Escherichia coli lawn serves as an experimental model system to study population expansions. Using an inkjet printer, we create well-defined replicates of the lawn and quantitatively study the population expansion of phage T7. The transient perturbations of the population front found in the experiments are well described by a model in which the front moves with constant speed. Independent of the precise details of the expansion, we show that obstacles create a kink in the front that persists over large distances and is insensitive to the details of the obstacle's shape. The small deviations between experimental findings and the predictions of the constant speed model can be understood with a more general reaction-diffusion model, which reduces to the constant speed model when the obstacle size is large compared to the front width. Using this framework, we demonstrate that frontier genotypes just grazing the side of an isolated obstacle increase in abundance, a phenomenon we call 'geometry-enhanced genetic drift', complementary to the founder effect associated with spatial bottlenecks. Bacterial range expansions around nutrient-poor barriers and stochastic simulations confirm this prediction. The effect of the obstacle on the genealogy of individuals at the front is characterized by simulations and rationalized using the constant speed model. Lastly, we consider the effect of two obstacles on front shape and genetic composition of the population illuminating the

  4. What are the Facilitators and Obstacles to Participation in Workplace Team Sport? A Qualitative Study

    Directory of Open Access Journals (Sweden)

    Andrew Brinkley

    2017-02-01

    Full Text Available Working age adults are failing to meet physical activity recommendations. Inactive behaviours are increasing costs for diminished individual and organisational health. The workplace is a priority setting to promote physical activity, however there is a lack of evidence about why some employees choose to participate in novel workplace activities, such as team sport, whilst others do not. The aim of this study was to explore the complexity of facilitators and obstacles associated with participation in workplace team sport.Twenty-nine semi-structured face-to-face and telephone interviews were conducted with office workers (58% female (36 ± 7.71 from manufacturing, public services, and educational services. Data was analysed through template analysis.Five sub-level (i.e., intrapersonal, interpersonal, organisational, community and societal influences facilitate participation or create obstacles for participants. Participants were challenged by a lack of competence, self-efficacy, negative sporting ideals and amotivation. Unhealthy competition, an unstable work-life balance and unsupportive colleagues created obstacles to participation. An unsupportive organisation and workplace culture placed demands on workplace champions, funding, facilities and communication. Healthy competitions, high perceptions of competence and self-efficacy, and being motivated autonomously enabled participation. Further, relatedness and social support created a physical activity culture where flexible working was encouraged and team sport was promoted in accessible locations within the organisation. Researchers should consider accounting for complexity of these influences. A participatory approach may tailor interventions to individual organisations and the employees that work within them. Interventions whereby autonomy, competence and relatedness are supported are recommended. This may be achieved by adapting sports and training workplace champions.

  5. Formation and obstacle avoidance control for multiagent systems

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    This paper considers the problems of formation and obstacle avoidance for multiagent systems.The objective is to design a term of agents that can reach a desired formation while avoiding collision with obstacles.To reduce the amount of information interaction between agents and target,we adopt the leader-follower formation strategy.By using the receding horizon control (RHC),an optimal problem is formulated in terms of cost minimization under constraints.Information on obstacles is incorporated online as se...

  6. Using Thermal Radiation in Detection of Negative Obstacles

    Science.gov (United States)

    Rankin, Arturo L.; Matthies, Larry H.

    2009-01-01

    A method of automated detection of negative obstacles (potholes, ditches, and the like) ahead of ground vehicles at night involves processing of imagery from thermal-infrared cameras aimed at the terrain ahead of the vehicles. The method is being developed as part of an overall obstacle-avoidance scheme for autonomous and semi-autonomous offroad robotic vehicles. The method could also be applied to help human drivers of cars and trucks avoid negative obstacles -- a development that may entail only modest additional cost inasmuch as some commercially available passenger cars are already equipped with infrared cameras as aids for nighttime operation.

  7. Getting to Darwin: Obstacles to Accepting Evolution by Natural Selection

    Science.gov (United States)

    Thagard, Paul; Findlay, Scott

    2010-06-01

    Darwin’s theory of evolution by natural selection is central to modern biology, but is resisted by many people. This paper discusses the major psychological obstacles to accepting Darwin’s theory. Cognitive obstacles to adopting evolution by natural selection include conceptual difficulties, methodological issues, and coherence problems that derive from the intuitiveness of alternative theories. The main emotional obstacles to accepting evolution are its apparent conflict with valued beliefs about God, souls, and morality. We draw on the philosophy of science and on a psychological theory of cognitive and emotional belief revision to make suggestions about what can be done to improve acceptance of Darwinian ideas.

  8. OBSTACLE DETECTION SYSTEM INVOLVING FUSION OF MULTIPLE SENSOR TECHNOLOGIES

    Directory of Open Access Journals (Sweden)

    C. Giannì

    2017-08-01

    Full Text Available Obstacle detection is a fundamental task for Unmanned Aerial Vehicles (UAV as a part of a Sense and Avoid system. In this study, we present a method of multi-sensor obstacle detection that demonstrated good results on different kind of obstacles. This method can be implemented on low-cost platforms involving a DSP or small FPGA. In this paper, we also present a study on the typical targets that can be tough to detect because of their characteristics of reflectivity, form factor, heterogeneity and show how data fusion can often overcome the limitations of each technology.

  9. Obstacle Effects on One-Dimensional Translocation of ATPase

    Institute of Scientific and Technical Information of China (English)

    WANG Xian-Ju; AI Bao-Quan; LIU Liang-Gang

    2002-01-01

    We apply a general random walk model to the study of the ATPase's one-dimensional translocation along obstacle biological environment, and show the effects of random obstacles on the ATPase translocation along single stranded DNA. We find that the obstacle environment can reduce the lifetime of ATPase lattice-bound state which results in the inhibition of ATPase activity. We also carry out the ranges of rate constant of ATPase unidirectonal translocation and bidirectional translocation. Our results are consistent with the experiments and relevant theoretical consideration, and can be used to explain some physiological phenomena.

  10. Obstacle detection of mobile robot based on data fusion

    Institute of Scientific and Technical Information of China (English)

    YUAN Xin; SU Li; SUN Li-ning

    2009-01-01

    To study the problem of obstacle detection based on multi-sensors data fusion, the multi-target track-ing theory and techniques are introduced into obstacle detection systems, and the exact position of obstacle can be determined. Data fusion problems are discussed directly based on achievable data from some sensors without considering the specific structure of each individual sensor. With respect to normal linear systems and nonlinear systems, the corresponding algorithms are proposed. The validity of the method is confirmed by simulation re-suits.

  11. 基于视觉传感器的障碍物检测%Obstacle detection based on vision sensor

    Institute of Scientific and Technical Information of China (English)

    王天涛; 赵永国; 常发亮

    2015-01-01

    针对移动机器人双目视觉障碍物检测的实时性和准确性两大难题,提出了一种适用于室内复杂背景的障碍物检测方法。通过Retinex图像增强操作消除环境光照不均匀的影响;运用扫描线种子填充算法分割图像中的路面、背景和障碍物;通过二值化处理、边缘检测提取障碍物的轮廓信息和位置信息。在AS-RE轮式机器人平台上进行实验,实验结果表明,机器人能够在室内环境中稳定地实现自主避障功能,验证了提出的双目视觉障碍物检测算法的可行性。%To solve real-time and accuracy problems of mobile robot obstacle detection based on binocular vision, a new obstacle detection method for complicated indoor background is proposed. The influence of non-homogeneous illumination is removed via Retinex image enhancement operation; The seed filling is used to implement segmentation of road face, background and obstacle;The contour and position information of obstacle is obtained after binaryzation, and edge detection. The test result on AS-RE robot shows that the new obstacle detection method is viable, and the automatic obstacle avoiding function is well realized stably.

  12. Effects of Obstacles on Flame Propagation Behavior and Explosion Overpressure Development During Gas Explosions in a Large Closed Tube

    Institute of Scientific and Technical Information of China (English)

    LI Xiao-dong; BAI Chun-hua; LIU Qing-ming

    2007-01-01

    AutoReaGas was used for the simulations of premixed gas/air mixtures explosion characteristics in obstacle-filled tubes with a cross-section of 0.2 m×0.2 m and the length of 28 m. Numerical analyses provide a quantitative descripti on of dependence of flame propagation speed and explosion overpressure on obstacles number, blockage ratio and interval distance. Computational results indicate that the obstacles play a significant role in determining the flame transmission speed and explosion overpressure in gas explosions. With the increase of blockage ratio, the explosion overpressure gradually rises. Nevertheless, the flame speed does not always increase along with increasing blockage ratio, but subsequently begins to decrease as the blockage ratio increases to some extend. Also, the interval distance between obstacles strongly influences flame behavior and explosion overpressure. When the obstacle interval distance is equal to inner diameter of the tube, the average flame speed in the obstacle zone and the peak overp ressure in tube all reach maximum values.

  13. How obstacles and facilitators predict academic performance: the mediating role of study burnout and engagement.

    Science.gov (United States)

    Salanova, Marisa; Schaufeli, Wilmar; Martinez, Isabel; Breso, Edgar

    2010-01-01

    Most people would agree with the maxim that "success breeds success." However, this is not the whole story. The current study investigated the additional impact of psychosocial factors (i.e., performance obstacles and facilitators) as well as psychological well-being (i.e., burnout and engagement) on success (i.e., academic performance). More specifically, our purpose was to show that, instead of directly affecting future performance, obstacles and facilitators exert an indirect effect via well-being. A total of 527 university students comprised the sample and filled out a questionnaire. We obtained their previous and future academic performance Grade Point Average (GPA) from the university's records. Structural equations modeling showed that the best predictor of future performance was the students' previous performance. As expected, study engagement mediated the relationship between performance obstacles and facilitators on the one hand, and future performance on the other. Contrary to expectations, burnout did not predict future performance, although, it is significantly associated with the presence of obstacles and the absence of facilitators. Our results illustrate that, although "success breeds success" (i.e., the best predictor of future performance is past performance), positive psychological states like study engagement are also important in explaining future performance, at least more so than negative states like study burnout.

  14. The efficient presentation - obstacles, strategies, success

    Directory of Open Access Journals (Sweden)

    Daniela-Elena Radu

    2007-12-01

    Full Text Available The making of presentations has become an omnipresent act of communication in the companies practice, but also in the didactic one. The notoriety and the increase of the importance of an efficient presentation lie in the transformations felt by a society of knowledge, communication being the answer in front of a constant information wave.Business people look in fear at the preparation of a presentation, the interaction with the audience andtheir feedback, all these leading to a low efficiency in transmitting the message.The speaker must overcome a group of obstacles, the most important being the reduced human capacityto capture the information transmitted orally; in this respect, he has available a group of visual instruments and strategies to capture the attention. In order to achieve efficiency one needs mental and emotional preparation, knowing the audience and the presentation’s objective and eliminating the old listing format in PowerPoint, for focusing the communication of the audience’s necessities. The present essay aims to analyze the verbal, non-verbal and para-verbal communication act that constitutes the base of any presentation, the reasons that lead to failure and the ways to increase efficiency, in order to succeed in transmitting a well structured and easy to remember message.Many researchers and practice workers within the communication, economic but also IT fields, have tried to find the solution for organizing and transmitting the message during a presentation, in accordance with the new technologies. In elaborating the present paper, we have used our personal experience and data obtained through 30 in-depth interviews,with managers in companies such Bostina Asociatii Skoda, Petrom etc.; we have used in our research articles of honored professors in social sciences from the Harvard and Stanford Universities , researches of the Minnesota and Ulster Universities, as well as works of specialists in marketing and information

  15. UOBPRM: A uniformly distributed obstacle-based PRM

    KAUST Repository

    Yeh, Hsin-Yi

    2012-10-01

    This paper presents a new sampling method for motion planning that can generate configurations more uniformly distributed on C-obstacle surfaces than prior approaches. Here, roadmap nodes are generated from the intersections between C-obstacles and a set of uniformly distributed fixed-length segments in C-space. The results show that this new sampling method yields samples that are more uniformly distributed than previous obstacle-based methods such as OBPRM, Gaussian sampling, and Bridge test sampling. UOBPRM is shown to have nodes more uniformly distributed near C-obstacle surfaces and also requires the fewest nodes and edges to solve challenging motion planning problems with varying narrow passages. © 2012 IEEE.

  16. Surrounding Moving Obstacle Detection for Autonomous Driving Using Stereo Vision

    Directory of Open Access Journals (Sweden)

    Hao Sun

    2013-06-01

    Full Text Available Detection and tracking surrounding moving obstacles such as vehicles and pedestrians are crucial for the safety of mobile robotics and autonomous vehicles. This is especially the case in urban driving scenarios. This paper presents a novel framework for surrounding moving obstacles detection using binocular stereo vision. The contributions of our work are threefold. Firstly, a multiview feature matching scheme is presented for simultaneous stereo correspondence and motion correspondence searching. Secondly, the multiview geometry constraint derived from the relative camera positions in pairs of consecutive stereo views is exploited for surrounding moving obstacles detection. Thirdly, an adaptive particle filter is proposed for tracking of multiple moving obstacles in surrounding areas. Experimental results from real‐world driving sequences demonstrate the effectiveness and robustness of the proposed framework.

  17. Design and Realization of Dynamic Obstacle on URWPSSim2D

    Directory of Open Access Journals (Sweden)

    Xiao Chen

    2013-07-01

    Full Text Available Simulation system is charged with the strategy validation and dual team meets, and as the 2-dimensional simulation platform for underwater robotic fish game, URWPGSim2D is the assigned platform for Chinese underwater robot contest and Robot cup underwater program. By now on URWPGSim2D, there is only static obstacles,thus short of changeableness. In order to improve the changeableness and innovation of robotic fish contest, to extend the space for the programming of contest strategy, and to increase the interest, this paper study the design of dynamic obstacles on URWPGSim2D, and design and implement two kinds of dynamic obstacles, which are the evadible dynamic obstacle and the forcing dribbling obstacle.  

  18. Surrounding Moving Obstacle Detection for Autonomous Driving Using Stereo Vision

    Directory of Open Access Journals (Sweden)

    Hao Sun

    2013-06-01

    Full Text Available Detection and tracking surrounding moving obstacles such as vehicles and pedestrians are crucial for the safety of mobile robotics and autonomous vehicles. This is especially the case in urban driving scenarios. This paper presents a novel framework for surrounding moving obstacles detection using binocular stereo vision. The contributions of our work are threefold. Firstly, a multiview feature matching scheme is presented for simultaneous stereo correspondence and motion correspondence searching. Secondly, the multiview geometry constraint derived from the relative camera positions in pairs of consecutive stereo views is exploited for surrounding moving obstacles detection. Thirdly, an adaptive particle filter is proposed for tracking of multiple moving obstacles in surrounding areas. Experimental results from real-world driving sequences demonstrate the effectiveness and robustness of the proposed framework.

  19. Optical Obstacle Avoidance System for Lunar and Mars Landing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The systems developed at fibertek for Obstacle-Avoidance has so far all been operated at 1560nm. Such an operation is required due to the required eye-safety...

  20. Monocular Obstacle Detection for Real-World Environments

    Science.gov (United States)

    Einhorn, Erik; Schroeter, Christof; Gross, Horst-Michael

    In this paper, we present a feature based approach for monocular scene reconstruction based on extended Kaiman filters (EKF). Our method processes a sequence of images taken by a single camera mounted in front of a mobile robot. Using various techniques we are able to produce a precise reconstruction that is almost free from outliers and therefore can be used for reliable obstacle detection and avoidance. In real-world field tests we show that the presented approach is able to detect obstacles that can not be seen by other sensors, such as laser range finders. Furthermore, we show that visual obstacle detection combined with a laser range finder can increase the detection rate of obstacles considerably, allowing the autonomous use of mobile robots in complex public and home environments.

  1. Thermal Activation of Dislocations in Large Scale Obstacle Bypass

    Energy Technology Data Exchange (ETDEWEB)

    Martinez Saez, Enrique [Los Alamos National Laboratory; Sobie, Cameron [Georgia Tech; Wen, Wei [Los Alamos National Laboratory; Capolungo, Laurent [Los Alamos National Laboratory; Patra, Anirban [Los Alamos National Laboratory; McDowell, David L. [Georgia Tech; Tome, Carlos [Los Alamos National Laboratory

    2016-08-18

    Irradiation-created defects diffuse and agglomerate presenting obstacles for the dislocation motion (both glide and climb). This effect leads to hardening and loss of toughness, which might drive the system to failure.

  2. Growing actin networks regulated by obstacle size and shape

    Science.gov (United States)

    Gong, Bo; Lin, Ji; Qian, Jin

    2017-01-01

    Growing actin networks provide the driving force for the motility of cells and intracellular pathogens. Based on the molecular-level processes of actin polymerization, branching, capping, and depolymerization, we have developed a modeling framework to simulate the stochastic and cooperative behaviors of growing actin networks in propelling obstacles, with an emphasis on the size and shape effects on work capacity and filament orientation in the growing process. Our results show that the characteristic size of obstacles changes the protrusion power per unit length, without influencing the orientation distribution of actin filaments in growing networks. In contrast, the geometry of obstacles has a profound effect on filament patterning, which influences the orientation of filaments differently when the drag coefficient of environment is small, intermediate, or large. We also discuss the role of various parameters, such as the aspect ratio of obstacles, branching rate, and capping rate, in affecting the protrusion power of network growth.

  3. Obstacle performance of cobalt-enriching crust wheeled mining vehicle

    Institute of Scientific and Technical Information of China (English)

    HUANG Zhong-hua; LIU Shao-jun; XIE Ya

    2006-01-01

    A cobalt-enriching crust mining vehicle with four independent driven wheels was proposed. The influence of center-of-gravity position of mining vehicle on obstacle performance was studied. The results show that the mining vehicle has optimal obstacle performance with center-of-gravity position in the middle of suspension. A virtual prototype based on ADAMS software was built and its obstacle performance was simulated. Simulation results show that the mining vehicle with four independent driven wheels has excellent obstacle performance, the maximum climbing capacity is no less than 30°, the maximal ditch width and shoulder height are no less than wheel radius ofmining vehicle. Thus wheeled mining vehicle is feasible for cobalt-enriching crust commercial mining.

  4. Beam coupling impedances of obstacles protruding into a beam pipe

    Science.gov (United States)

    Kurennoy, Sergey S.

    1997-03-01

    The beam coupling impedances of small obstacles protruding inside the vacuum chamber of an accelerator are calculated at frequencies for which the wavelength is large compared to a typical size of the obstacle. Formulas for a few important particular cases including both essentially three-dimensional objects like a post or a mask and axisymmetric irises, are presented. These results allow simple practical estimates of the broadband impedance contributions from such discontinuities.

  5. Beam coupling impedances of obstacles protruding into a beam pipe

    Energy Technology Data Exchange (ETDEWEB)

    Kurennoy, S.S. [AOT-1, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    1997-03-01

    The beam coupling impedances of small obstacles protruding inside the vacuum chamber of an accelerator are calculated at frequencies for which the wavelength is large compared to a typical size of the obstacle. Formulas for a few important particular cases including both essentially three-dimensional objects like a post or a mask and axisymmetric irises, are presented. These results allow simple practical estimates of the broadband impedance contributions from such discontinuities. {copyright} {ital 1997} {ital The American Physical Society}

  6. Surrounding Moving Obstacle Detection for Autonomous Driving Using Stereo Vision

    OpenAIRE

    Hao Sun; Huanxin Zou; Shilin Zhou; Cheng Wang; Naser El-Sheimy

    2013-01-01

    Detection and tracking surrounding moving obstacles such as vehicles and pedestrians are crucial for the safety of mobile robotics and autonomous vehicles. This is especially the case in urban driving scenarios. This paper presents a novel framework for surrounding moving obstacles detection using binocular stereo vision. The contributions of our work are threefold. Firstly, a multiview feature matching scheme is presented for simultaneous stereo correspondence and motion correspondence searc...

  7. Simultaneous contrast restoration and obstacles detection : First results

    OpenAIRE

    HAUTIERE, N; TAREL, JP; Aubert, D

    2007-01-01

    Reliable obstacles detection under adverse weather conditions especially foggy conditions, is a challenging task because the contrast is drastically reduced. Consequently, the classical approaches relying on pattern recognition techniques or points of interest matching are not so efficient anymore. In this paper, a novel approach is proposed which is able to simultaneously restore the contrast of the scene and to detect the presence of obstacles by stereovision once the atmosphere opacity is ...

  8. Robust Tracking Control of Mobile Robot Formation with Obstacle Avoidance

    OpenAIRE

    Tiantian Yang; Zhiyuan Liu; Hong Chen; Run Pei

    2007-01-01

    We consider the formation control problem of multiple wheeled mobile robots with parametric uncertainties and actuator saturations in the environment with obstacles. First, a nonconvex optimization problem is introduced to generate the collision-free trajectory. If the robots tracking along the reference trajectory find themselves moving close to the obstacles, a new collision-free trajectory is generated automatically by solving the optimization problem. Then, a distributed control scheme...

  9. Wind turbines: current status, obstacles, trends and technologies

    Science.gov (United States)

    Konstantinidis, E. I.; Botsaris, P. N.

    2016-11-01

    The last decade the installation of wind farms around the world is spreading rapidly and wind energy has become a significant factor for promoting sustainable development. The scope of the present study is to indicate the present status of global wind power expansion as well as the current state of the art in the field of wind turbine technology. The RAM (reliability/availability/maintenance) section is also examined and the Levelized Cost of Energy for onshore/ offshore electricity production is presented. Negative consequences that go with the rapid expansion of wind power like accidents, environmental effects, etc. are highlighted. Especially visual impact to the landscape and noise pollution are some factors that provoke social reactions. Moreover, the complicated and long permitted process of a wind power plant, the high capital cost of the investment and the grid instability due to the intermittent nature of wind, are also significant obstacles in the development of the wind energy production. The current trends in the field of research and development of onshore and offshore wind power production are analyzed. Finally the present study is trying to achieve an estimation of where the wind industry targets for the years to come.

  10. Obstacles to integrated pest management adoption in developing countries.

    Science.gov (United States)

    Parsa, Soroush; Morse, Stephen; Bonifacio, Alejandro; Chancellor, Timothy C B; Condori, Bruno; Crespo-Pérez, Verónica; Hobbs, Shaun L A; Kroschel, Jürgen; Ba, Malick N; Rebaudo, François; Sherwood, Stephen G; Vanek, Steven J; Faye, Emile; Herrera, Mario A; Dangles, Olivier

    2014-03-11

    Despite its theoretical prominence and sound principles, integrated pest management (IPM) continues to suffer from anemic adoption rates in developing countries. To shed light on the reasons, we surveyed the opinions of a large and diverse pool of IPM professionals and practitioners from 96 countries by using structured concept mapping. The first phase of this method elicited 413 open-ended responses on perceived obstacles to IPM. Analysis of responses revealed 51 unique statements on obstacles, the most frequent of which was "insufficient training and technical support to farmers." Cluster analyses, based on participant opinions, grouped these unique statements into six themes: research weaknesses, outreach weaknesses, IPM weaknesses, farmer weaknesses, pesticide industry interference, and weak adoption incentives. Subsequently, 163 participants rated the obstacles expressed in the 51 unique statements according to importance and remediation difficulty. Respondents from developing countries and high-income countries rated the obstacles differently. As a group, developing-country respondents rated "IPM requires collective action within a farming community" as their top obstacle to IPM adoption. Respondents from high-income countries prioritized instead the "shortage of well-qualified IPM experts and extensionists." Differential prioritization was also evident among developing-country regions, and when obstacle statements were grouped into themes. Results highlighted the need to improve the participation of stakeholders from developing countries in the IPM adoption debate, and also to situate the debate within specific regional contexts.

  11. A Hybrid Architecture for Vision-Based Obstacle Avoidance

    Directory of Open Access Journals (Sweden)

    Mehmet Serdar Güzel

    2013-01-01

    Full Text Available This paper proposes a new obstacle avoidance method using a single monocular vision camera as the only sensor which is called as Hybrid Architecture. This architecture integrates a high performance appearance-based obstacle detection method into an optical flow-based navigation system. The hybrid architecture was designed and implemented to run both methods simultaneously and is able to combine the results of each method using a novel arbitration mechanism. The proposed strategy successfully fused two different vision-based obstacle avoidance methods using this arbitration mechanism in order to permit a safer obstacle avoidance system. Accordingly, to establish the adequacy of the design of the obstacle avoidance system, a series of experiments were conducted. The results demonstrate the characteristics of the proposed architecture, and the results prove that its performance is somewhat better than the conventional optical flow-based architecture. Especially, the robot employing Hybrid Architecture avoids lateral obstacles in a more smooth and robust manner than when using the conventional optical flow-based technique.

  12. Face-Lift

    Science.gov (United States)

    Tests and Procedures Face-lift By Mayo Clinic Staff A face-lift (rhytidectomy) is a cosmetic surgical procedure to improve the look of your face and neck. During a face-lift, facial soft tissues are lifted, excess skin is ...

  13. What’s in a Face? How Face Gender and Current Affect Influence Perceived Emotion

    Science.gov (United States)

    Harris, Daniel A.; Hayes-Skelton, Sarah A.; Ciaramitaro, Vivian M.

    2016-01-01

    Faces drive our social interactions. A vast literature suggests an interaction between gender and emotional face perception, with studies using different methodologies demonstrating that the gender of a face can affect how emotions are processed. However, how different is our perception of affective male and female faces? Furthermore, how does our current affective state when viewing faces influence our perceptual biases? We presented participants with a series of faces morphed along an emotional continuum from happy to angry. Participants judged each face morph as either happy or angry. We determined each participant’s unique emotional ‘neutral’ point, defined as the face morph judged to be perceived equally happy and angry, separately for male and female faces. We also assessed how current state affect influenced these perceptual neutral points. Our results indicate that, for both male and female participants, the emotional neutral point for male faces is perceptually biased to be happier than for female faces. This bias suggests that more happiness is required to perceive a male face as emotionally neutral, i.e., we are biased to perceive a male face as more negative. Interestingly, we also find that perceptual biases in perceiving female faces are correlated with current mood, such that positive state affect correlates with perceiving female faces as happier, while we find no significant correlation between negative state affect and the perception of facial emotion. Furthermore, we find reaction time biases, with slower responses for angry male faces compared to angry female faces. PMID:27733839

  14. Challenges facing production grids

    Energy Technology Data Exchange (ETDEWEB)

    Pordes, Ruth; /Fermilab

    2007-06-01

    Today's global communities of users expect quality of service from distributed Grid systems equivalent to that their local data centers. This must be coupled to ubiquitous access to the ensemble of processing and storage resources across multiple Grid infrastructures. We are still facing significant challenges in meeting these expectations, especially in the underlying security, a sustainable and successful economic model, and smoothing the boundaries between administrative and technical domains. Using the Open Science Grid as an example, I examine the status and challenges of Grids operating in production today.

  15. Haar-like Features for Robust Real-Time Face Recognition

    DEFF Research Database (Denmark)

    Nasrollahi, Kamal; Moeslund, Thomas B.

    2013-01-01

    Face recognition is still a very challenging task when the input face image is noisy, occluded by some obstacles, of very low-resolution, not facing the camera, and not properly illuminated. These problems make the feature extraction and consequently the face recognition system unstable....... The proposed system in this paper introduces the novel idea of using Haar-like features, which have commonly been used for object detection, along with a probabilistic classifier for face recognition. The proposed system is simple, real-time, effective and robust against most of the mentioned problems...

  16. Free Enterprise and Entrepreneurship in Serbia: An Analysis of Motivations, Financing and Obstacles

    Directory of Open Access Journals (Sweden)

    Nina Radojevich-Kelley

    2011-01-01

    Full Text Available Problem statement: Entrepreneurship is considered to be a major driving force to economic development throughout the world. Free enterprise is challenging in any country, especially in a developing nation such as Serbia where communism and socialism prevailed for decades. The purpose of this study is to examine entrepreneurship and free enterprise in Serbia as well as the challenges or obstacles they face. The hope is to understand how Serbian entrepreneurs operate in their nation, especially since little is known about them. Approach: A questionnaire was designed and distributed to a sample of Serbian entrepreneurs. Descriptive statistics were calculated based on responses from participants. The study investigates 59 entrepreneurs; identifying commonalities in funding, motivation behind entrepreneurship and common challenges they face. Underlying similarities or differences are examined. Results: Empirical evidence indicates that the majority of Serbian entrepreneurs rely on equity funding to finance their ventures, form businesses to pursue personal freedom, bootstrap their nascent firms and provide services or represent/sell someone else’s products rather than create their own. Results indicate that the greatest challenges to Serbian business owners are with administrative issues associated with their government, political instability and economic uncertainty. Analogous to the USA, Serbian entrepreneurs create business for freedom, independence and monetary gain. Conclusion: The overall results of the study confirm the benefit of entrepreneurship in the transitioning economy, while highlighting the many obstacles that entrepreneurs face. Results indicate that entrepreneurship in Serbia is gaining interest due to the belief that it promotes a better life. Political instability, uncertainty about the future, difficulty obtaining clients and general inexperience pose the greatest threats to Serbian business owners. As

  17. Innovating Responsibly in ICT for Ageing: Drivers, Obstacles and Implementation

    Directory of Open Access Journals (Sweden)

    Kate Chatfield

    2017-06-01

    Full Text Available Responsible research and innovation (RRI is a nascent concept, promoted actively by the European Union and other policy makers around the world. Hitherto, this concept has been associated primarily with publicly funded activities but given the considerable proportion of research and innovation that is undertaken in the private sector, RRI will be rendered irrelevant unless it is adopted by industry. This paper introduces a private sector perspective of RRI, specifically that of the information and communication technology (ICT industry, working in the field of healthy ageing. Drawing upon empirical data from 30 in-depth interviews with key industry representatives from across Europe, it explores: (a the level of awareness of RRI; (b the drivers and obstacles influencing its implementation; and (c the factors deemed vital for facilitation of RRI in industry. The findings paint a varied picture, including significant concerns about adoption of RRI in an industry environment where the economic implications of all activities must be considered carefully. However, some companies have found their own ways to balance financial and altruistic goals, suggesting that there is both a willingness and a place for an RRI-type governance framework within the private sector.

  18. Overcoming the obstacles: Life stories of scientists with learning disabilities

    Science.gov (United States)

    Force, Crista Marie

    Scientific discovery is at the heart of solving many of the problems facing contemporary society. Scientists are retiring at rates that exceed the numbers of new scientists. Unfortunately, scientific careers still appear to be outside the reach of most individuals with learning disabilities. The purpose of this research was to better understand the methods by which successful learning disabled scientists have overcome the barriers and challenges associated with their learning disabilities in their preparation and performance as scientists. This narrative inquiry involved the researcher writing the life stories of four scientists. These life stories were generated from extensive interviews in which each of the scientists recounted their life histories. The researcher used narrative analysis to "make sense" of these learning disabled scientists' life stories. The narrative analysis required the researcher to identify and describe emergent themes characterizing each scientist's life. A cross-case analysis was then performed to uncover commonalities and differences in the lives of these four individuals. Results of the cross-case analysis revealed that all four scientists had a passion for science that emerged at an early age, which, with strong drive and determination, drove these individuals to succeed in spite of the many obstacles arising from their learning disabilities. The analysis also revealed that these scientists chose careers based on their strengths; they actively sought mentors to guide them in their preparation as scientists; and they developed coping techniques to overcome difficulties and succeed. The cross-case analysis also revealed differences in the degree to which each scientist accepted his or her learning disability. While some demonstrated inferior feelings about their successes as scientists, still other individuals revealed feelings of having superior abilities in areas such as visualization and working with people. These individuals revealed

  19. Obstacles to early career psychiatrists practicing psychotherapy.

    Science.gov (United States)

    Clemens, Norman A; Plakun, Eric M; Lazar, Susan G; Mellman, Lisa

    2014-09-01

    Though psychiatric residents are expected to be competent psychotherapists on graduation, further growth in skill and versatility requires continued experience in their ongoing career. Maturity as a psychotherapist is essential because a psychiatrist is the only mental health provider who, as a physician, can assume full responsibility for biopsychosocial patient care and roles as supervisor, consultant, and team leader. Graduating residents face an environment in which surveys show a steady and alarming decline in practice of psychotherapy by psychiatrists, along with a decline in job satisfaction. High educational debts, practice structures, intrusive management, and reimbursement policies that devalue psychotherapy discourage early career psychiatrists from a practice style that enables providing it. For the early-career psychiatrist there is thus the serious risk of being unable to develop a critical mass of experience or a secure identity as a psychiatric psychotherapist. Implementation of parity laws and the Affordable Care Act (ACA) will affect the situation in unpredictable ways that call for vigilance and active response. Additional service and administrative demands may result from the ACA, creating ethical dilemmas about meeting urgent patient needs versus biopsychosocial standards of care. The authors recommend 1) vigorous advocacy for better payment levels for psychotherapy and freedom from disruptive management; 2) aggressive action against violations of the parity act, 3) active preparation of psychiatric residents for dealing with career choices and the environment for providing psychotherapy in their practice, and 4) post-graduate training in psychotherapy through supervision/consultation, continuing education courses, computer instruction, and distance learning.

  20. Covert face priming reveals a 'true face effect' in a case of congenital prosopagnosia.

    Science.gov (United States)

    Striemer, Christopher; Gingerich, Trevor; Striemer, Danielle; Dixon, Mike

    2009-12-01

    Previous research indicates that individuals with congenital prosopagnosia (CP) fail to demonstrate significant priming from faces to related names in covert recognition tasks. The interpretation has been that CP precludes the ability to acquire face representations. In the current study we replicated this important finding. In addition, we also demonstrated significant 'true face effect' in a CP patient, where face primes that matched the probe names facilitated reaction times compared to unrelated face primes. These data suggest that some individuals with CP may possess degraded face representations that facilitate the priming of a person's identity, but not semantic associates.

  1. Obstacle Avoidance in Groping Locomotion of a Humanoid Robot

    Directory of Open Access Journals (Sweden)

    Masahiro Ohka

    2008-11-01

    Full Text Available This paper describes the development of an autonomous obstacle-avoidance method that operates in conjunction with groping locomotion on the humanoid robot Bonten-Maru II. Present studies on groping locomotion consist of basic research in which humanoid robot recognizes its surroundings by touching and groping with its arm on the flat surface of a wall. The robot responds to the surroundings by performing corrections to its orientation and locomotion direction. During groping locomotion, however, the existence of obstacles within the correction area creates the possibility of collisions. The objective of this paper is to develop an autonomous method to avoid obstacles in the correction area by applying suitable algorithms to the humanoid robot's control system. In order to recognize its surroundings, six-axis force sensors were attached to both robotic arms as end effectors for force control. The proposed algorithm refers to the rotation angle of the humanoid robot's leg joints due to trajectory generation. The algorithm relates to the groping locomotion via the measured groping angle and motions of arms. Using Bonten-Maru II, groping experiments were conducted on a wall's surface to obtain wall orientation data. By employing these data, the humanoid robot performed the proposed method autonomously to avoid an obstacle present in the correction area. Results indicate that the humanoid robot can recognize the existence of an obstacle and avoid it by generating suitable trajectories in its legs.

  2. Laser-Based Obstacle Detection at Railway Level Crossings

    Directory of Open Access Journals (Sweden)

    Vítor Amaral

    2016-01-01

    Full Text Available This paper presents a system for obstacle detection in railway level crossings from 3D point clouds acquired with tilting 2D laser scanners. Although large obstacles in railway level crossings are detectable with current solutions, the detection of small obstacles remains an open problem. By relying on a tilting laser scanner, the proposed system is able to acquire highly dense and accurate point clouds, enabling the detection of small obstacles, like rocks laying near the rail. During an offline training phase, the system learns a background model of the level crossing from a set of point clouds. Then, online, obstacles are detected as occupied space contrasting with the background model. To reduce the need for manual on-site calibration, the system automatically estimates the pose of the level crossing and railway with respect to the laser scanner. Experimental results show the ability of the system to successfully perform on a set of 41 point clouds acquired in an operational one-lane level crossing.

  3. Sensorimotor Model of Obstacle Avoidance in Echolocating Bats.

    Directory of Open Access Journals (Sweden)

    Dieter Vanderelst

    2015-10-01

    Full Text Available Bat echolocation is an ability consisting of many subtasks such as navigation, prey detection and object recognition. Understanding the echolocation capabilities of bats comes down to isolating the minimal set of acoustic cues needed to complete each task. For some tasks, the minimal cues have already been identified. However, while a number of possible cues have been suggested, little is known about the minimal cues supporting obstacle avoidance in echolocating bats. In this paper, we propose that the Interaural Intensity Difference (IID and travel time of the first millisecond of the echo train are sufficient cues for obstacle avoidance. We describe a simple control algorithm based on the use of these cues in combination with alternating ear positions modeled after the constant frequency bat Rhinolophus rouxii. Using spatial simulations (2D and 3D, we show that simple phonotaxis can steer a bat clear from obstacles without performing a reconstruction of the 3D layout of the scene. As such, this paper presents the first computationally explicit explanation for obstacle avoidance validated in complex simulated environments. Based on additional simulations modelling the FM bat Phyllostomus discolor, we conjecture that the proposed cues can be exploited by constant frequency (CF bats and frequency modulated (FM bats alike. We hypothesize that using a low level yet robust cue for obstacle avoidance allows bats to comply with the hard real-time constraints of this basic behaviour.

  4. Interaction of turbulent deflagrations with representative flow obstacles

    Energy Technology Data Exchange (ETDEWEB)

    Durst, B.; Ardey, N.; Mayinger, F. [Lehrstul a fuer Thermodynamik, Technische Universitat Munchen (Germany)

    1997-03-01

    In the case of a gradual release of hydrogen in the course of an assumed, severe accident in a light water reactor, the combustion will normally start out as a slow deflagration. Acceleration of an initially slow flame due to interactions of chemical kinetics and turbulent heat and mass transfer can result in very high flame speeds. Therefore, in order to assess hydrogen mitigation techniques, detailed knowledge about flame acceleration and interaction of flames with obstacles is required. The reported investigations are aimed at the investigation of the mechanisms responsible for turbulent flame acceleration and improving present correlations for estimates and models for numerical simulations of hydrogen combustion processes. A medium-scale square cross-section setup is employed, using flow obstacles with shapes representative for reactor containments. The global flame speed is deduced from measurements using thermocouples, pressure transducers and photodiodes. Measurements using a two-component LDA-system are being carried through in order to correlate global flame spread and local turbulence parameters. Results indicate that low blockage-ratio obstacles only marginally influence the flame, as disturbances which are induced remain local to the vicinity of the obstacle and die out very quickly downstream thereof. Flow visualizations by means of a Schlieren setup indicate very complex flow structures in the vicinity of obstacles. The results are being used to validate turbulent reaction models. A model based on probability density functions (pdf) of assumed shape has been developed and initial calculations are presented. (author)

  5. The influence of object identity on obstacle avoidance reaching behaviour.

    Science.gov (United States)

    de Haan, A M; Van der Stigchel, S; Nijnens, C M; Dijkerman, H C

    2014-07-01

    When reaching for target objects, we hardly ever collide with other objects located in our working environment. Behavioural studies have demonstrated that the introduction of non-target objects into the workspace alters both spatial and temporal parameters of reaching trajectories. Previous studies have shown the influence of spatial object features (e.g. size and position) on obstacle avoidance movements. However, obstacle identity may also play a role in the preparation of avoidance responses as this allows prediction of possible negative consequences of collision based on recognition of the obstacle. In this study we test this hypothesis by asking participants to reach towards a target as quickly as possible, in the presence of an empty or full glass of water placed about half way between the target and the starting position, at 8 cm either left or right of the virtual midline. While the spatial features of full and empty glasses of water are the same, the consequences of collision are clearly different. Indeed, when there was a high chance of collision, reaching trajectories veered away more from filled than from empty glasses. This shows that the identity of potential obstacles, which allows for estimating the predicted consequences of collision, is taken into account during obstacle avoidance.

  6. Autonomous obstacle avoidance using visual fixation and looming

    Science.gov (United States)

    Joarder, Kunal; Raviv, Daniel

    1992-11-01

    This paper describes a vision-based method for avoiding obstacles using the concepts of visual looming and fixating motion. Visual looming refers to the expansion of images of objects in the retina. Usually, this is due to the decreasing distance between the observer and the object. An increasing looming value signifies an increasing threat of collision with the object. The visual task of avoiding collision can be further simplified by purposive control of visual fixation at the objects in front of the moving camera. Using these two basic concepts real time obstacle avoidance in a tight perception-action loop is implemented. Three-dimensional space in front of the camera is divided into zones with various degrees of looming-based threat of collision. For each obstacle seen by a fixating camera, looming and its time derivative are calculated directly from the 2-D image. Depending on the threat posed by an obstacle, a course change is dictated. This looming based approach is simple, independent of the size of the 3-D object and its range and involves simple quantitative measurements. Results pertinent to a camera on a robot arm navigating between obstacles are presented.

  7. Development of an optimal velocity selection method with velocity obstacle

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Min Geuk; Oh, Jun Ho [KAIST, Daejeon (Korea, Republic of)

    2015-08-15

    The Velocity obstacle (VO) method is one of the most well-known methods for local path planning, allowing consideration of dynamic obstacles and unexpected obstacles. Typical VO methods separate a velocity map into a collision area and a collision-free area. A robot can avoid collisions by selecting its velocity from within the collision-free area. However, if there are numerous obstacles near a robot, the robot will have very few velocity candidates. In this paper, a method for choosing optimal velocity components using the concept of pass-time and vertical clearance is proposed for the efficient movement of a robot. The pass-time is the time required for a robot to pass by an obstacle. By generating a latticized available velocity map for a robot, each velocity component can be evaluated using a cost function that considers the pass-time and other aspects. From the output of the cost function, even a velocity component that will cause a collision in the future can be chosen as a final velocity if the pass-time is sufficiently long enough.

  8. Aerosol dry deposition on canopies of plane obstacles

    Science.gov (United States)

    Petroff, A.; Zhang, L.

    2007-12-01

    A new model to describe aerosol transport and dry deposition on vegetative canopies has been proposed recently by Petroff et al. and applied to canopies of cylindrical obstacles such as coniferous forest (Petroff et al., 2007, Aerosol dry deposition on vegetative canopies. Part II: A new modeling approach and applications, submitted to Atmospheric Environment). In the present study, the approach is extended to canopies of plane obstacles such as grass, crop or broadleaf forest. The model takes into account the characteristics of the canopy, the aerosol and the aerodynamics. Deposition terms are modeled following an up-scaling procedure, which is based on the knowledge of collection dynamics on each individual obstacle and on the statistical distribution of these collecting elements. The statistical description applies to geometrical properties such as leaf characteristic length and orientation. Deposition mechanisms considered in this model include Brownian diffusion, interception, inertial impaction, turbulent impaction and gravitational settling. For interception, no adequate parameterisation is available in the literature to describe the collection on individual obstacle. Thus, an original parameterisation is derived for plane obstacle and is based on potential flow theory. Aerosol transport is described in a mono-dimensional configuration and neutral stratification of the atmosphere is assumed. Preliminary results indicate that the present model agrees with existing measurements data obtained both in wind-tunnel and on site.

  9. Obstacles in Advancement of Young Female Geoscientists: Research Results from the Earth Science Women's Network (ESWN)

    Science.gov (United States)

    Kogan, M.; Laursen, S. L.

    2011-12-01

    requiring couples to consider two STEM careers when making career decisions. Women's partners more often worked full time than did the partners of men. This may limit the possibility of work-related travel for female geoscientists and increase the burden of household duties on two working partners. In fact, women did report doing significantly more household upkeep and more parenting than men. Another barrier to retention and promotion of women includes a lack of mentors and role models. The example of women in senior positions is especially important, justifying young women's aspiration to be successful geoscientists. In our data, young female geoscientists less often saw women as adequately represented in senior roles than did male respondents. While ESWN cannot solve these problems for individuals, ESWN activities do seem to address these concerns. In discussions on the ESWN listserv, women share ideas and strategies for navigating these obstacles. Young female geoscientists may also find role models among the more experienced members. Knowledge of these obstacles also provides ESWN and other organizations aiming to advance women in science with the potential best practices in supporting women through these challenges.

  10. Normal composite face effects in developmental prosopagnosia.

    Science.gov (United States)

    Biotti, Federica; Wu, Esther; Yang, Hua; Jiahui, Guo; Duchaine, Bradley; Cook, Richard

    2017-08-10

    Upright face perception is thought to involve holistic processing, whereby local features are integrated into a unified whole. Consistent with this view, the top half of one face appears to fuse perceptually with the bottom half of another, when aligned spatially and presented upright. This 'composite face effect' reveals a tendency to integrate information from disparate regions when faces are presented canonically. In recent years, the relationship between susceptibility to the composite effect and face recognition ability has received extensive attention both in participants with normal face recognition and participants with developmental prosopagnosia. Previous results suggest that individuals with developmental prosopagnosia may show reduced susceptibility to the effect suggestive of diminished holistic face processing. Here we describe two studies that examine whether developmental prosopagnosia is associated with reduced composite face effects. Despite using independent samples of developmental prosopagnosics and different composite procedures, we find no evidence for reduced composite face effects. The experiments yielded similar results; highly significant composite effects in both prosopagnosic groups that were similar in magnitude to the effects found in participants with normal face processing. The composite face effects exhibited by both samples and the controls were greatly diminished when stimulus arrangements were inverted. Our finding that the whole-face binding process indexed by the composite effect is intact in developmental prosopagnosia indicates that other factors are responsible for developmental prosopagnosia. These results are also inconsistent with suggestions that susceptibility to the composite face effect and face recognition ability are tightly linked. While the holistic process revealed by the composite face effect may be necessary for typical face perception, it is not sufficient; individual differences in face recognition ability

  11. Challenges facing academic urology training programs: an impending crisis.

    Science.gov (United States)

    Gonzalez, Chris M; McKenna, Patrick

    2013-03-01

    To determine the most pressing issues facing academic urology training centers. The supply of urologists per capita in the United States continues to decrease. Stricter resident requirements, restriction of resident duty hours, and a Graduate Medical Education (GME) funding cap on resident education has led to significant challenges for academic centers. A 32-question survey was sent to Society of University Urologists members. Respondents defined themselves as academic faculty tenure track, program director, academic chair, program director and academic chair, clinical faculty nontenure track, and community faculty member. A total of 143 of 446 members(32%) responded. A lack of funding was indicated as an obstacle to adding new residency positions (65% respondents) and recruiting new faculty (60% respondents). Residency positions not funded by GME (40% respondents) required either clinical or hospital dollars to support these slots. Most respondents (51%) indicated resident research rotations are funded with clinical dollars. Surgical skills laboratories are commonly used (85% respondents) and are supported mostly with hospital or clinical dollars. The majority of respondents (84%) indicated they would expand simulation laboratories if they had better funding. Other than urodynamics and ultrasound, urology residency training programs reported little income from ancillary dollars. There is a significant workforce shortage within urology training programs. Clinical revenue and hospital funding seem to be the main financial support engines to supplement the GME funding shortage, proficiency training, and faculty salary support for teaching. The current system of GME funding for urology residency programs is not sustainable. Published by Elsevier Inc.

  12. OBSTACLES TO ONLINE SHOPPING: IMPACT OF GENDER AND INTERNET SECURITY ISSUES

    Directory of Open Access Journals (Sweden)

    AHU GENİS-GRUBER

    2013-06-01

    Full Text Available In the latest technology era, the widespread usage of internet enabled individuals to interact continuously and led to altered buying behavior patterns. Literature focuses on the critical effects in the field. Among many antecedents to online shopping, previous studies point out two important obstacles:  (i acceptance and tendency to use technology in accordance with gender perceptions and (ii internet security problems. This study analyzes the impact of these two prominent factors on e-commerce utilization by studying the effects of these factors through primary and secondary data; a survey designed specifically for this analysis and the cross-country data from Eurostat. The findings show that while internet security problems significantly impact online shopping behavior, the evidence is mixed for the impact of gender. The results of this paper provide insights for a successful e-commerce transaction and identify important obstacles to be avoided for an efficient e-commerce system.

  13. General practitioners' knowledge, practices, and obstacles in the diagnosis and management of dementia.

    Science.gov (United States)

    Pathak, Krishna P; Montgomery, Anthony

    2015-01-01

    To identify general practitioners' (GPs) knowledge, practices, and obstacles with regard to the diagnosis and management of dementia. Standardized questionnaires covering knowledge, practices, and obstacles were distributed among a purposive sample of GPs in Kathmandu, Nepal. Three hundred and eighty GPs responded (response rate = 89%). Knowledge of practitioners' with regard to the diagnosis and management of dementia was unsatisfactory (management barriers are presented with regard to GP, patient, and carer factors. Specifically, the results address the following issues: communicating the diagnosis, negative views of dementia, difficulty diagnosing early-stage dementia, acceptability of specialists, responsibility for extra issues, knowledge of dementia and aging, less awareness of declining abilities, diminished resources to handle care, lack of specific guidelines, and poor awareness of epidemiology. Demographic changes mean that dementia will represent a significant problem in the future. The following paper outlines the problems and solutions that the Nepalese medical community needs to adopt to deal effectively with diagnosis, care, and management of dementia.

  14. MHD mixed convection flow through a diverging channel with heated circular obstacle

    Science.gov (United States)

    Alam, Md. S.; Shaha, J.; Khan, M. A. H.; Nasrin, R.

    2016-07-01

    A numerical study of steady MHD mixed convection heat transfer and fluid flow through a diverging channel with heated circular obstacle is carried out in this paper. The circular obstacle placed at the centre of the channel is hot with temperature Th. The top and bottom walls are non-adiabatic. The basic nonlinear governing partial differential equations are transformed into dimensionless ordinary differential equations using similarity transformations. These equations have been solved numerically for different values of the governing parameters, namely Reynolds number (Re), Hartmann number (Ha), Richardson number (Ri) and Prandtl number (Pr) using finite element method. The streamlines, isotherms, average Nusselt number and average temperature of the fluid for various relevant dimensionless parameters are displayed graphically. The study revealed that the flow and thermal fields in the diverging channel depend significantly on the heated body. In addition, it is observed that the magnetic field acts to increase the rate of heat transfer within the channel.

  15. The Obstacle Problem for the A-Harmonic Equation

    Directory of Open Access Journals (Sweden)

    Zhenhua Cao

    2010-01-01

    Full Text Available Firstly, we define an order for differential forms. Secondly, we also define the supersolution and subsolution of the A-harmonic equation and the obstacle problems for differential forms which satisfy the A-harmonic equation, and we obtain the relations between the solutions to A-harmonic equation and the solution to the obstacle problem of the A-harmonic equation. Finally, as an application of the obstacle problem, we prove the existence and uniqueness of the solution to the A-harmonic equation on a bounded domain Ω with a smooth boundary ∂Ω, where the A-harmonic equation satisfies d⋆A(x,du=0,x∈Ω; u=ρ,x∈∂Ω, where ρ is any given differential form which belongs to W1,p(Ω,Λl-1.

  16. Getting Obstacle Avoidance Trajectory of Mobile Beacon for Localization

    Directory of Open Access Journals (Sweden)

    Huan-Qing CUI

    2010-11-01

    Full Text Available Localization is one of the most important technologies in wireless sensor network, and mobile beacon assisted localization is a promising localization method. The mobile beacon trajectory planning is a basic and important problem in these methods. There are many obstacles in the real world, which obstruct the moving of mobile beacon. This paper focuses on the obstacle avoidance trajectory planning scheme. After partitioning the deployment area with fixed cell decomposition, the beacon trajectory are divided into global and local trajectory. The approximate shortest global trajectory is obtained by depth-first search, greedy strategy method and ant colony algorithm, while local trajectory is any existing trajectories. Simulation results show that this method can avoid obstacles in the network deployment area, and the smaller cell size leads to longer beacon trajectory and more localizable sensor nodes.

  17. Real-time obstacle avoidance using harmonic potential functions

    Science.gov (United States)

    Kim, Jin-Oh; Khosla, Pradeep K.

    1992-01-01

    This paper presents a new formulation of the artificial potential approach to the obstacle avoidance problem for a mobile robot or a manipulator in a known environment. Previous formulations of artificial potentials for obstacle avoidance have exhibited local minima in a cluttered environment. To build an artificial potential field, harmonic functions that completely eliminate local minima even for a cluttered environment are used. The panel method is employed to represent arbitrarily shaped obstacles and to derive the potential over the whole space. Based on this potential function, an elegant control strategy is proposed for the real-time control of a robot. The harmonic potential, the panel method, and the control strategy are tested with a bar-shaped mobile robot and a three-degree-of-freedom planar redundant manipulator.

  18. Mobile Robot Path Planning with Randomly Moving Obstacles and Goal

    Directory of Open Access Journals (Sweden)

    Vanitha Aenugu

    2012-03-01

    Full Text Available This article presents the dynamic path planning for a mobile robot to track a randomly moving goal with avoidance of multiple randomly moving obstacles. The main feature of the developed scheme is its capability of dealing with the situation that the paths of both the goal and the obstacles are unknown a priori to the mobile robot. A new mathematical approach that is based on the concepts of 3-D geometry is proposed to generate the path of the mobile robot. The mobile robot decides its path in real time to avoid the randomly moving obstacles and to track the randomly moving goal. The developed scheme results in faster decision-making for successful goal tracking. 3-D simulations using MATLAB validate the developed scheme.

  19. About (above) a face - a face

    OpenAIRE

    2009-01-01

    This text intents to unfold some considerations regardind the perception of the image of the Lóri’s face, from the book Uma aprendizagem ou o livro dos prazeres, published by Clarice Lispector in 1969. For that, will be studied the politicians devices who involve the apprehension of the face as a qualifying of the subject and, at the same time, its relation with the lenguage.

  20. About (above a face - a face

    Directory of Open Access Journals (Sweden)

    Diego Cervelin

    2009-07-01

    Full Text Available This text intents to unfold some considerations regardind the perception of the image of the Lóri’s face, from the book Uma aprendizagem ou o livro dos prazeres, published by Clarice Lispector in 1969. For that, will be studied the politicians devices who involve the apprehension of the face as a qualifying of the subject and, at the same time, its relation with the lenguage.

  1. 跨越大学生人际交往心理障碍的策略%The Strategies of Overcoming Psychological Obstacles in College Students' Interpersonal Communication

    Institute of Scientific and Technical Information of China (English)

    周丽欣

    2015-01-01

    随着经济和社会的快速发展,当代大学生所面临的问题不仅是学习和就业,还有人际交往障碍问题。本文分析了影响大学生人际交往能力的主要心理障碍,提出了跨越大学生人际交往心理障碍的相应策略。%With the rapid development of economic and society, the problems contemporary college students are facing lies not only in study and employment, but also in interpersonal communication obstacles. This paper analyzes the main psychological obstacles that influence college student's interpersonal skills, and puts forward some corresponding strategies to help college students to overcome interpersonal communication psychological ob-stacles.

  2. Collision rates for rare cell capture in periodic obstacle arrays strongly depend on density of cell suspension.

    Science.gov (United States)

    Cimrák, I

    2016-11-01

    Recently, computational modelling has been successfully used for determination of collision rates for rare cell capture in periodic obstacle arrays. The models were based on particle advection simulations where the cells were advected according to velocity field computed from two dimensional Navier-Stokes equations. This approach may be used under the assumption of very dilute cell suspensions where no mutual cell collisions occur. We use the object-in-fluid framework to demonstrate that even with low cell-to-fluid ratio, the optimal geometry of the obstacle array significantly changes. We show computational simulations for ratios of 3.5, 6.9 and 10.4% determining the optimal geometry of the periodic obstacle arrays. It was already previously demonstrated that cells in periodic obstacle arrays follow trajectories in two modes: the colliding mode and the zig-zag mode. The colliding mode maximizes the cell-obstacle collision frequency. Our simulations reveal that for dilute suspensions and for suspensions with cell-to-fluid ratio 3.5%, there is a range of column shifts for which the cells follow colliding trajectories. However we showed, that for 6.9 and 10.4%, the cells never follow colliding trajectories.

  3. SIGNIFICANT ABSENCE

    Directory of Open Access Journals (Sweden)

    Suzan Orhan

    2015-03-01

    Full Text Available Photographing the city pertains to photo-graphing architectural features, historic sites, streets, crowds, signs, the underground, crime, entertainment, recreational facilities, ruins, traces, and space. City, on the other hand, pertains to residential space that is de-stroyed and reconstructed at certain turning points due to economic, cultural, architectural, and demographic reasons.This study will attempt to examine the photographer as the subject as well as the boundaries of her photo-graphic designations in the face of urban renewal through sample projects. Also functioning as a part of the memory industry, which has been formed during the last half-century that simultaneously witnessed memory loss and memory boom, photography, albeit through certain projects, has proven the possibility of a critical gaze at social and individual testimonials. When Eugene Atget's photos of the old Paris which he took between 1898-1924 out of commercial concerns is viewed as a milestone, Antoine D'Agata's Psychogeographie (2005 and other similar projects can be said to not only docu-ment urban change and transformation but also act as intermediaries of defiance against separation from the accustomed living areas.

  4. Hybrid Genetic Algorithm with Fuzzy Logic Controller for Obstacle Location-Allocation Problem

    Science.gov (United States)

    Taniguchi, Jyunichi; Wang, Xiaodong; Gen, Mitsuo; Yokota, Takao

    Location-allocation problem is known as one of the important problems faced in Industrial Engineering/Operations Research fields. One of important logistic tasks is transfer of manufactured products from plants to customers. If there is a need to supply products to large number of customers in a wide area, it is disadvantageous to deliver products from the only central distribution center or direct from plants. It is suitable to build up local distribution centers. In literature, different location models have been used according to characteristics of a distribution area. However, most of them related the location problem without obstacle. In this paper, an extended location-allocation problem with obstacles is considered. Since this problem is very complex and with many infeasible solutions, no direct method is effective to solve it, we propose a hybrid Genetic Algorithm (hGA) for effectively solving this problem. The proposed hGA combines two efficient methods based on Lagrangian relaxation and Dijkstra’s shortest path algorithm. To improve the performance of the proposed hGA, a Fuzzy Logic Controller (FLC) approach is also adopted to auto-tune the GA parameters.

  5. Educational pathways of Black women physicists: Stories of experiencing and overcoming obstacles in life

    Science.gov (United States)

    Rosa, Katemari

    2017-01-01

    This talk presents an empirical study on the underrepresentation of people of color in scientific careers. Grounded in Critical Race Theory, the presentation examines the lived experiences of six Black women physicists in the United States, addresses obstacles faced in their career paths, and strategies used to overcome these obstacles. Data for this study were collected through semi-structured interviews and coded for emergent themes, which are invitation to engage in science, communities of science practices, and isolation in the academy. The findings reveal that college recruitment and funding were fundamental for these women to choose Physics over other STEM fields. The analysis shows Physics can be a hostile environment for these women. In addition, Black women experience unique challenges of socialization in Physics, particularly by exclusion of study groups. In this talk, suggestions will be presented to make Physics departments a more inclusive space to support Black women in science. This presentation is based on work supported by the Brazilian government through CAPES (BEX1907-07-7), the Fulbright Program, Comissño Fulbright Brasil, and the Office of Diversity at Teachers College, Columbia University.

  6. Legal obstacles and incentives to the development of small scale hydroelectric power in West Virginia

    Energy Technology Data Exchange (ETDEWEB)

    None,

    1980-05-01

    The legal and institutional obstacles to the development of small-scale hydroelectric in West Virginia at the state level are described. The Federal government also exercises extensive regulatory authority in the area. The introductory section examines the dual regulatory system from the standpoint of the appropriate legal doctrine, the law of pre-emption, application of the law to the case of hydroelectric development, and concludes with an inquiry into the practical use of the doctrine by FERC. The development of small-scale hydroelectric energy depends on the selection of a site which will produce sufficient water power capacity to make the project economically attractive to a developer. In West Virginia, the right to use the flowing waters of a stream, creek, or river is appurtenant to the ownership of the lands bordering the watercourse. The lands are known as riparian lands. The water rights are known as riparian rights. Thus, the first obstacle a developer faces involves the acquisition of riparian lands and the subsequent right to the use of the water. The water law in West Virginia is discussed in detail followed by discussions on direct and indirect regulations; continuing obligations; financial considerations; and interstate organizations.

  7. ON THE HYPERBOLIC OBSTACLE PROBLEM OF FIRST ORDER

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This paper presents new results for strong solutions and their coincidence sets of the obstacle problem for linear hyperbolic operators of first order. An inequality similar to the LewyStampacchia ones for elliptic and parabolic problems is shown. Under nondegeneracy conditions the stability of the coincidence set is shown with respect to the variation of the data and with respect to approximation by semilinear hyperbolic problems. These results are applied to the asymptotic stability of the evolution problem with respect to the stationary coercive problem with obstacle.

  8. A Hands-Free Obstacle Detection and Avoidance System

    Directory of Open Access Journals (Sweden)

    M. Abdul-Niby

    2015-06-01

    Full Text Available In this paper, we present a low cost hands-free detection and avoidance system designed to provide mobility assistance for visually impaired people. An ultrasonic sensor is attached to the jacket of the user and detects the obstacles in front. The information obtained is transferred to the user through audio messages and also by a vibration. The range of the detection is user-defined. A text-to-speech module is employed for the voice signal. The proposed obstacle avoidance device is cost effective, easy to use and easily upgraded.

  9. Beam coupling impedances of obstacles protruding into beam pipe

    Energy Technology Data Exchange (ETDEWEB)

    Kurennoy, S.S.

    1997-08-01

    The beam coupling impedances of small obstacles protruding inside the vacuum chamber of an accelerator are calculated analytically at frequencies for which the wavelength is large compared to a typical size of the obstacle. Simple formulas for a few important particular cases, including both essentially three-dimensional objects like a post or a mask and axisymmetric irises, are presented. The analytical results are compared and agree with three-dimensional computer simulations. These results allow simple practical estimates of the broad-band impedance contributions from such discontinuities.

  10. Beam Coupling Impedances of Obstacles Protruding into Beam Pipe.

    Science.gov (United States)

    Kurennoy, Sergey S.

    1997-05-01

    The beam coupling impedances of small obstacles protruding inside the vacuum chamber of an accelerator are calculated analytically at frequencies for which the wavelength is large compared to a typical size of the obstacle. Simple formulas for a few important particular cases including both essentially three-dimensional objects like a post or a mask and axisymmetric irises, are presented. The analytical results are compared and agree with three-dimensional computer simulations. These results allow simple practical estimates of the broad-band impedance contributions from such discontinuities.

  11. Instabilities developed in stratified flows over pronounced obstacles

    Science.gov (United States)

    Varela, J.; Araújo, M.; Bove, I.; Cabeza, C.; Usera, G.; Martí, Arturo C.; Montagne, R.; Sarasúa, L. G.

    2007-12-01

    In the present work we study numerical and experimentally the flow of a two-layer stratified fluid over a topographic obstacle. The problem reflects a wide number of oceanographic and meteorological situations, where the stratification plays an important role. We identify the different instabilities developed by studying the pycnocline deformation due to a pronounced obstacle. The numerical simulations were made using the model caffa3D.MB which works with a numerical model of Navier-Stokes equations with finite volume elements in curvilinear meshes. The experimental results are contrasted with numerical simulations. Linear stability analysis predictions are checked with particle image velocimetry (PIV) measurements.

  12. Advanced Fuzzy Potential Field Method for Mobile Robot Obstacle Avoidance.

    Science.gov (United States)

    Park, Jong-Wook; Kwak, Hwan-Joo; Kang, Young-Chang; Kim, Dong W

    2016-01-01

    An advanced fuzzy potential field method for mobile robot obstacle avoidance is proposed. The potential field method primarily deals with the repulsive forces surrounding obstacles, while fuzzy control logic focuses on fuzzy rules that handle linguistic variables and describe the knowledge of experts. The design of a fuzzy controller--advanced fuzzy potential field method (AFPFM)--that models and enhances the conventional potential field method is proposed and discussed. This study also examines the rule-explosion problem of conventional fuzzy logic and assesses the performance of our proposed AFPFM through simulations carried out using a mobile robot.

  13. Advanced Fuzzy Potential Field Method for Mobile Robot Obstacle Avoidance

    Science.gov (United States)

    Park, Jong-Wook; Kwak, Hwan-Joo; Kang, Young-Chang; Kim, Dong W.

    2016-01-01

    An advanced fuzzy potential field method for mobile robot obstacle avoidance is proposed. The potential field method primarily deals with the repulsive forces surrounding obstacles, while fuzzy control logic focuses on fuzzy rules that handle linguistic variables and describe the knowledge of experts. The design of a fuzzy controller—advanced fuzzy potential field method (AFPFM)—that models and enhances the conventional potential field method is proposed and discussed. This study also examines the rule-explosion problem of conventional fuzzy logic and assesses the performance of our proposed AFPFM through simulations carried out using a mobile robot. PMID:27123001

  14. Advanced Fuzzy Potential Field Method for Mobile Robot Obstacle Avoidance

    Directory of Open Access Journals (Sweden)

    Jong-Wook Park

    2016-01-01

    Full Text Available An advanced fuzzy potential field method for mobile robot obstacle avoidance is proposed. The potential field method primarily deals with the repulsive forces surrounding obstacles, while fuzzy control logic focuses on fuzzy rules that handle linguistic variables and describe the knowledge of experts. The design of a fuzzy controller—advanced fuzzy potential field method (AFPFM—that models and enhances the conventional potential field method is proposed and discussed. This study also examines the rule-explosion problem of conventional fuzzy logic and assesses the performance of our proposed AFPFM through simulations carried out using a mobile robot.

  15. Obstacles to Rural Residents’ Consumption in China and the Countermeasures

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    On the basis of relevant statistical data, this paper analyzes the obstacles to rural residents’ consumption in China as follows: the consumption structure is restricted critically; the consumption environment cannot meet the need of social development; the traditional consumption concept has not yet been changed; the social security system is not sound; the support of rural finance is short. Pointed countermeasures for eliminating the obstacles to rural residents’ consumption are put forward as follows: first, adopt effective measures to elevate the level of farmers’ income; second, strengthen the credit support of rural finance; third, quicken the pace of modernized development in rural areas; fourth, construct perfect rural social security system.

  16. LS and MMSE based Localization Algorithm for WSNs amid obstacles

    Directory of Open Access Journals (Sweden)

    Z.Mary Livinsa

    2014-01-01

    Full Text Available In recent years, optimization and Wireless Sensor Networks (WSNs are extensively used in numerous milieus and hostile topographies. In this paper, we proposed an improved localization algorithm by means of Least square and Minimum mean square error that evolvements with the basic DV-Hop algorithm. The localization error is shortened by our proposed algorithm and improves the localization accuracy of the basic DV-Hop algorithm with minimum number of beacon nodes. The proposed method is simulated and compared with other algorithms such as DV-Hop, ROCRSSI and APIT. The simulation is considered both with obstacle as well as without obstacle.

  17. OBSTACLE-AVOIDANCE NAVIGATION OF MULTIPLE MOBILE ROBOTS

    Institute of Scientific and Technical Information of China (English)

    罗青; 李智军; 吕恬生

    2002-01-01

    In the context of robot soccer, the robots have to select actions to achieve individual and team goals in the dynamic environment. It is important for a robot to acquire navigation behaviors for avoiding other robots and obstacles in the real-time environment. This paper suggested an efficient approach to collision-avoidance in multirobot system. This approach is based on velocity information of moving objects and the distance between robot and obstacle in three specified directions. The main contribution of this paper is that it provides a method for robots with decreased-computational cost and makes the robot navigate without collision with each other in a complicated environment.

  18. Dissociating Face Identity and Facial Expression Processing Via Visual Adaptation

    Directory of Open Access Journals (Sweden)

    Hong Xu

    2012-10-01

    Full Text Available Face identity and facial expression are processed in two distinct neural pathways. However, most of the existing face adaptation literature studies them separately, despite the fact that they are two aspects from the same face. The current study conducted a systematic comparison between these two aspects by face adaptation, investigating how top- and bottom-half face parts contribute to the processing of face identity and facial expression. A real face (sad, “Adam” and its two size-equivalent face parts (top- and bottom-half were used as the adaptor in separate conditions. For face identity adaptation, the test stimuli were generated by morphing Adam's sad face with another person's sad face (“Sam”. For facial expression adaptation, the test stimuli were created by morphing Adam's sad face with his neutral face and morphing the neutral face with his happy face. In each trial, after exposure to the adaptor, observers indicated the perceived face identity or facial expression of the following test face via a key press. They were also tested in a baseline condition without adaptation. Results show that the top- and bottom-half face each generated a significant face identity aftereffect. However, the aftereffect by top-half face adaptation is much larger than that by the bottom-half face. On the contrary, only the bottom-half face generated a significant facial expression aftereffect. This dissociation of top- and bottom-half face adaptation suggests that face parts play different roles in face identity and facial expression. It thus provides further evidence for the distributed systems of face perception.

  19. Effects of socks which improved foot sensation on velocity and stride length of elderly subjects crossing obstacles.

    Science.gov (United States)

    Yoo, Won-Gyu

    2015-08-01

    [Purpose] We developed socks which improve foot sensation and investigated their effect on the velocity and stride length of elderly women crossing obstacles. [Subjects] Ten community-dwelling, elderly women who could walk independently were recruited. [Methods] We measured velocity and stride length using the GAITRite system while the participants crossed obstacles under three conditions: barefoot, wearing ordinary socks, and wearing the socks which improve foot sensation. [Results] Velocity and stride length in bare feet and when wearing the sense-improving socks increased significantly compared to their values when wearing standard socks. Velocity and stride length did not differ between the bare foot and improved sock conditions. [Conclusion] Wearing socks helps protect the foot, but can decrease foot sensory input. Therefore, the socks which improve foot sensation were useful for preventing falls and protecting the feet of the elderly women while they crossed obstacles.

  20. Optimisation of pipeline route in the presence of obstacles based on a least cost path algorithm and laplacian smoothing

    Directory of Open Access Journals (Sweden)

    Ju Young Kang

    2017-09-01

    Full Text Available Subsea pipeline route design is a crucial task for the offshore oil and gas industry, and the route selected can significantly affect the success or failure of an offshore project. Thus, it is essential to design pipeline routes to be eco-friendly, economical and safe. Obstacle avoidance is one of the main problems that affect pipeline route selection. In this study, we propose a technique for designing an automatic obstacle avoidance. The Laplacian smoothing algorithm was used to make automatically generated pipeline routes fairer. The algorithms were fast and the method was shown to be effective and easy to use in a simple set of case studies.

  1. Social Attributions from Faces : Determinants, Consequences, Accuracy, and Functional Significance

    NARCIS (Netherlands)

    Todorov, Alexander; Olivola, Christopher Y; Dotsch, Ron; Mende-Siedlecki, Peter

    2015-01-01

    Since the early twentieth century, psychologists have known that there is consensus in attributing social and personality characteristics from facial appearance. Recent studies have shown that surprisingly little time and effort are needed to arrive at this consensus. Here we review recent research

  2. Social attributions from faces: Determinants, consequences, accuracy, and functional significance

    NARCIS (Netherlands)

    Todorov, A.T.; Olivola, C.Y.; Dotsch, R.; Mende-Siedlecki, P.

    2015-01-01

    Since the early twentieth century, psychologists have known that there is consensus in attributing social and personality characteristics from facial appearance. Recent studies have shown that surprisingly little time and effort are needed to arrive at this consensus. Here we review recent research

  3. Human faces are slower than chimpanzee faces.

    Directory of Open Access Journals (Sweden)

    Anne M Burrows

    Full Text Available BACKGROUND: While humans (like other primates communicate with facial expressions, the evolution of speech added a new function to the facial muscles (facial expression muscles. The evolution of speech required the development of a coordinated action between visual (movement of the lips and auditory signals in a rhythmic fashion to produce "visemes" (visual movements of the lips that correspond to specific sounds. Visemes depend upon facial muscles to regulate shape of the lips, which themselves act as speech articulators. This movement necessitates a more controlled, sustained muscle contraction than that produced during spontaneous facial expressions which occur rapidly and last only a short period of time. Recently, it was found that human tongue musculature contains a higher proportion of slow-twitch myosin fibers than in rhesus macaques, which is related to the slower, more controlled movements of the human tongue in the production of speech. Are there similar unique, evolutionary physiologic biases found in human facial musculature related to the evolution of speech? METHODOLOGY/PRINICIPAL FINDINGS: Using myosin immunohistochemistry, we tested the hypothesis that human facial musculature has a higher percentage of slow-twitch myosin fibers relative to chimpanzees (Pan troglodytes and rhesus macaques (Macaca mulatta. We sampled the orbicularis oris and zygomaticus major muscles from three cadavers of each species and compared proportions of fiber-types. Results confirmed our hypothesis: humans had the highest proportion of slow-twitch myosin fibers while chimpanzees had the highest proportion of fast-twitch fibers. CONCLUSIONS/SIGNIFICANCE: These findings demonstrate that the human face is slower than that of rhesus macaques and our closest living relative, the chimpanzee. They also support the assertion that human facial musculature and speech co-evolved. Further, these results suggest a unique set of evolutionary selective pressures on

  4. An Investigation about obstacles of Mobile Commerce in Iran (A case study in Saravan City

    Directory of Open Access Journals (Sweden)

    Baqer Kord

    2012-03-01

    Full Text Available The main purpose of the present paper is an investigation about obstacles and challenges in development of mobile commerce in Iran. To notice the present infrastructure and the ratio of high influence of mobile commerce and its availability and being at the hand of common people as one of main tools in mobile commerce, in the world as well as in Iran, people have tendency and are going for mobile commerce and it is also attracting general attentions of people. In this paper it investigate the unique benefits of mobile commerce using a descriptive field survey to access barriers and obstacles which are facing to the development of mobile commerce. Samples and statistical research population are teachers in Saravan city of Sistan and Baluchestan in south of Iran which are using mobile phone for paying light and water bills or doing business and financial transactions. The samples were choosing among 300 of so-call teachers which selected in order random tools of data collection was questionnaire which collected after 15 days. The data were analyzed by SPSS software. The result of this analysis is showing that information technology, in the development of mobile commerce is facing many problems and challenges such as: the limitation in extension of internet band, inappropriate user accepted connector mobile equipments, none existence of using mobile commerce culture in trade, lack of the security feeling for users technical equipment limitations and also mobile network stability. And scale of importance of each one from the view of users is different. At the end to overcome these problems and barriers and to accelerate the development of mobile commerce which is the requirement of the modern life, with the results based on and come out from the present paper some strategies are going to be shown.

  5. Adult Self directed Learning Obstacle Factors and Coping%成人自我导向学习的障碍因素及应对

    Institute of Scientific and Technical Information of China (English)

    孙文杰; 赵联凤

    2014-01-01

    As the main way of adult learning ,the self directed learning plays an important role in the adult learning .Adults live in an open ,complex social situation ,so that their self directed learning is faced with many obstacles ,such as the motivation obstacle ,will obstacle ,learning strategies obstacle , emotion obstacle and situation obstacle and so on .In order to help the adult to overcome the obstacles of self directed learning and improve the ability of self directed learning ,we can take the following measures :Inspiring the interior motivation of the adult learning ;strengthening the guidance of self directed learning strategy ;focusing on the mental health education of adults ;increasing the support from all sectors of the community for the self directed learning in adult .%自我导向学习作为成人学习的主要方式,在成人学习中占有重要地位。成人处于一个开放、复杂的社会情境之中,因而他们的自我导向学习面临着诸多障碍,如动机障碍、意志障碍、学习策略障碍、情感障碍和情境障碍等。通过激发成人学习的内部动机,加强自我导向学习策略指导,关注成人心理健康教育,加大对成人自我导向学习的支持力度等策略,不仅可以帮助成人克服自我导向学习障碍,而且可以有效提高成人自我导向学习的能力。

  6. Pre-hospital Obstacles in Thrombolytic Therapy and Suggested Solutions

    Directory of Open Access Journals (Sweden)

    Betül Tekin Güveli

    2015-12-01

    Full Text Available INTRODUCTION: Acute ischemic stroke is frequently encountered in emergency neurology clinics. Especially when administered within 3 hours of symptom onset, thrombolytic therapy is important in reducing ischemic injury and neurological disability. In this study, we aimed to investigate the demographic and clinical characteristics according to application time, to identify situations which pose an obstacle to thrombolytic therapy and to review the thrombolytic therapy results in patients diagnosed with acute ischemic stroke. METHODS: The patients diagnosed with acute ischemic stroke were evaluated and their age, gender, complaints, risk factors, previous history of stroke, with whom they live, how they arrived at the hospital and their application time information were recorded. Those who were admitted within 3 hours of symptom onset were assessed as early, those admitted after 3 hours were assessed as late admission. Then the rate of thrombolytic therapy, final results and the clinical status in early admission patients and the reasons for delay in late admission patients were discussed. RESULTS: Among 361 acute ischemic stroke patients, the mean age was 66±14,1. 111 patients were admitted within 3 hours of symptom onset, 246 patients were admitted after three hours. Patients arriving to emergency room with 112 Ambulance Service were admitted earlier than those brought in by family, and this difference was statistically significant. The most common causes of time loss in late admissions were the patients being referred from other centers and the unawareness of family about the importance of the disease. There were 13 patients treated with thrombolytic therapy, and complications occurred in one patient. DISCUSSION AND CONCLUSION: Thrombolytic therapy is important in acute ischemic stroke for suitable patients.Our study suggested that the most important factors in spreading of performing the thrombolytic therapy are informing the public about

  7. Control of micronutrient deficiencies in India: obstacles and strategies.

    Science.gov (United States)

    Vijayaraghavan, K

    2002-05-01

    Micronutrient deficiencies of vitamin A, iron, and iodine continue to be of public health significance in India. The government of India initiated national programs to prevent, control and combat these deficiencies and their serious consequences. The interventions involved (1) distribution of iodized salt in the endemic areas, (2) administration of semiannual massive dose of vitamin A to young children, and (3) distribution of iron-folic acid tablets to the vulnerable groups. Evaluations revealed that the biologic impact of these interventions was unsatisfactory. Inadequate allocation of funds (10% of the actual needs) necessary to cover the enormous number of beneficiaries was one of the important obstacles. Consequently, the allocation of supplies to different provinces was far short of the requirements (10-30%). As a result of poor orientation, the functionaries were not adhering to the guidelines, leading to woefully inadequate (1-20%) and irregular coverage. There was no proper monitoring or supervision to make midcourse corrections to improve the functioning. The community was not informed of the purpose and details of each intervention. Hence, it did not utilize the resources completely and remained passive recipients. The community was not aware of the dietary approaches to prevent micronutrient disorders owing to absence of nutrition education. With the adoption of National Nutrition Policy by the government of India, a concerted and focused approach should be adopted. The future strategies should include a mix of short-term supplementation and food-based strategy encompassing food fortification and home gardening. Innovative approaches in information, education, and communication (such as social marketing strategy) for making the interventions sustainable should be adopted.

  8. TEACHING GEOGRAPHY AND THE NOTION OF EPISTEMOLOGICAL OBSTACLE

    Directory of Open Access Journals (Sweden)

    Julio Cesar Epifanio Machado

    2012-06-01

    Full Text Available ABSTRACT: Even in the twenty-first century book "A formação do espírito científico: contribuição para uma psicanálise do conhecimento" Gaston Bachelard (1884-1962, published in France in 1938, contributes significantly in the critical analysis of knowledge socially organized and everyday life. This review seeks to establish approaches to the notion of epistemological obstacles, discussed at length in that work, the scientific geographical thought regarding politics, economics, culture, nature and teaching. Inspired by this epistemological debate, strategic issues are threaded throughout the text, proposing cuts study on specific topic addressed, especially with regard to the planning of geography lessons in Basic Education. RESUMO: Ainda no século XXI o livro “A formação do espírito científico: contribuição para uma psicanálise do conhecimento”, de Gaston Bachelard (1884-1962, publicado na França em 1938, contribuí de forma salutar na análise crítica do conhecimento socialmente organizado e cotidiano. Essa resenha procura estabelecer aproximações da noção de Obstáculo Epistemológico, discutida detidamente na referida obra, do pensamento geográfico científico referente à política, economia, cultura, natureza e didática. Inspirando-se nessa discussão epistemológica, questões estratégicas são encadeadas ao longo do texto, propondo recortes de estudo específicos diante do tema tratado, principalmente no que diz respeito ao planejamento das aulas de geografia na Educação Básica.

  9. Mechanical energy assessment of adult with Down syndrome during walking with obstacle avoidance.

    Science.gov (United States)

    Salami, Firooz; Vimercati, Sara Laura; Rigoldi, Chiara; Taebi, Amirtaha; Albertini, Giorgio; Galli, Manuela

    2014-08-01

    The aim of this study is analyzing the differences between plane walking and stepping over an obstacle for two groups of healthy people and people with Down syndrome and then, evaluating the movement efficiency between the groups by comprising of their mechanical energy exchanges. 39 adults including two groups of 21 people with Down syndrome (age: 21.6 ± 7 years) and 18 healthy people (age: 25.1 ± 2.4 years) participated in this research. The test has been done in two conditions, first in plane walking and second in walking with an obstacle (10% of the subject's height). The gait data were acquired using quantitative movement analysis, composed of an optoelectronic system (Elite2002, BTS) with eight infrared cameras. Mechanical energy exchanges are computed by dedicated software and finally the data including spatiotemporal parameters, mechanical energy parameters and energy recovery of gait cycle are analyzed by statistical software to find significant differences. Regards to spatiotemporal parameters velocity and step length are lower in people with Down syndrome. Mechanical energy parameters particularly energy recovery does not change from healthy people to people with Down syndrome. However, there are some differences in inter-group through plane walking to obstacle avoidance and it means people with Down syndrome probably use their residual abilities in the most efficient way to achieve the main goal of an efficient energy recovery.

  10. Space-time separation during obstacle-avoidance learning in monkeys.

    Science.gov (United States)

    Torres, Elizabeth; Andersen, Richard

    2006-11-01

    Is the movement duration time known before we move? To answer this question, a new experimental paradigm is introduced that for the first time monitors the acquisition of a new motor skill in rhesus monkeys. Straight reaches were interleaved with reaches around physical obstacles that elicited a different path geometry. Curved and longer spatial paths were immediately resolved and consistent over months of training. A new temporal strategy separately evolved over repetitions from multiple to a single velocity peak. We propose that the obstacle-avoidance spatial paths were resolved before motion execution and used as reference in the computation of the new dynamics. Path conservation from the first trial occurred both at the hand and at the joint angle levels, whereas the speed profile dramatically changed over time. The spatial solution required no learning and was anticipated by the spontaneous repositioning of the initial arm posture. The learning was in the temporal domain, involving the adjustment of the speed during the motion's first impulse. Within the movement initiation, the partial distance traveled by the hand up to the first velocity peak was finely tuned under a constant time. For a given space location, the time of the first impulse remained robust to learning, but significantly shifted for different targets and obstacle configurations. Differences in the temporal-related parameters across time provided a clear distinction between learning and automatic behavior.

  11. Wing wear reduces bumblebee flight performance in a dynamic obstacle course.

    Science.gov (United States)

    Mountcastle, Andrew M; Alexander, Teressa M; Switzer, Callin M; Combes, Stacey A

    2016-06-01

    Previous work has shown that wing wear increases mortality in bumblebees. Although a proximate mechanism for this phenomenon has remained elusive, a leading hypothesis is that wing wear increases predation risk by reducing flight manoeuvrability. We tested the effects of simulated wing wear on flight manoeuvrability in Bombus impatiens bumblebees using a dynamic obstacle course designed to push bees towards their performance limits. We found that removing 22% wing area from the tips of both forewings (symmetric wear) caused a 9% reduction in peak acceleration during manoeuvring flight, while performing the same manipulation on only one wing (asymmetric wear) did not significantly reduce maximum acceleration. The rate at which bees collided with obstacles was correlated with body length across all treatments, but wing wear did not increase collision rate, possibly because shorter wingspans allow more room for bees to manoeuvre. This study presents a novel method for exploring extreme flight manoeuvres in flying insects, eliciting peak accelerations that exceed those measured during flight through a stationary obstacle course. If escape from aerial predation is constrained by acceleration capacity, then our results offer a potential explanation for the observed increase in bumblebee mortality with wing wear.

  12. Obstacle avoidance during human walking: transfer of motor skill from one leg to the other.

    Science.gov (United States)

    van Hedel, H J A; Biedermann, M; Erni, T; Dietz, V

    2002-09-01

    The aim of this study was to evaluate whether a newly acquired locomotor skill can be transferred to the mirror condition. Subjects were trained to step over an obstacle on a treadmill, the appearance of which was signalled by an acoustic stimulus, while visual information was prevented. Feedback information about foot clearance was provided by acoustic signals. During two successive runs (each consisting of 100 steps over the obstacle) the same leg was leading (i.e. the leg crossing the obstacle first). In the following third run, the leading and trailing legs were changed. During each of the three successive runs the adaptational changes were analysed by recording leg muscle electromyographic (EMG) activity, joint angle trajectories and foot clearance over the obstacle. The training effect gained between the first and second runs and the transfer to the mirror condition (third run) were evaluated. Adaptational changes of all measures, except ankle joint trajectory, could to a significant extent be transferred to the mirror condition. No side-specific differences in the amount of transfer were found, neither from the right to the left side, nor vice versa. These observations are at variance with adaptational changes observed during split-belt walking or one-legged hopping on a treadmill, where no transfer to the mirror condition occurred. It is assumed that this might be due to the specific requirements of the tasks and the leg muscles involved. While in the split-belt and hopping experiments leg extensor muscles are mainly involved, leg flexors predominate in the performance of the present task. It is hypothesised that the learning effects observed in the present experiments are mediated at a higher level (e.g. brainstem) of locomotor control.

  13. Overcoming Obstacles to Collaboration and Integration in Physical Education.

    Science.gov (United States)

    Rees, C. Roger; And Others

    1991-01-01

    Identifies subdisciplinary fragmentation, academic elitism, and negative stereotyping as obstacles impeding the process of collaboration among different groups of professionals in physical education. The article presents examples of projects in which academics interacted among themselves and with physical education teachers, classroom teachers,…

  14. On a Highly Nonlinear Self-Obstacle Optimal Control Problem

    Energy Technology Data Exchange (ETDEWEB)

    Di Donato, Daniela, E-mail: daniela.didonato@unitn.it [University of Trento, Department of Mathematics (Italy); Mugnai, Dimitri, E-mail: dimitri.mugnai@unipg.it [Università di Perugia, Dipartimento di Matematica e Informatica (Italy)

    2015-10-15

    We consider a non-quadratic optimal control problem associated to a nonlinear elliptic variational inequality, where the obstacle is the control itself. We show that, fixed a desired profile, there exists an optimal solution which is not far from it. Detailed characterizations of the optimal solution are given, also in terms of approximating problems.

  15. Obstacles and Opportunities for Critical Thinking in Japan.

    Science.gov (United States)

    Davidson, Bruce W.

    Paradoxically, Japan presents both a difficult and promising setting for the advancement of critical thinking skills. One deep-rooted obstacle stems from anti-rational ideological traditions and prejudices. Another comes from the rigidly hierarchical, conformist nature of Japanese society, which does not encourage divergent opinions or their…

  16. Muscular responses and movement strategies during stumbling over obstacles

    NARCIS (Netherlands)

    Schillings, AM; Van Wezel, BMH; Mulder, T; Duysens, J

    2000-01-01

    Muscular responses and movement strategies during stumbling over obstacles. J. Neurophysiol. 83: 2093-2102, 2000. Although many studies have investigated reflexes after stimulation of either cutaneous or proprioceptive afferents, much less is known about responses after more natural perturbations, s

  17. Robot vision: obstacle-avoidance techniques for unmanned aerial vehicles

    NARCIS (Netherlands)

    Carloni, Raffaella; Lippiello, Vincenzo; D'auria, Massimo; Fumagalli, Matteo; Mersha, Abeje Y.; Stramigioli, Stefano; Sicilano, Bruno

    2013-01-01

    In this article, a vision-based technique for obstacle avoidance and target identification is combined with haptic feedback to develop a new teleoperated navigation system for underactuated aerial vehicles in unknown environments. A three-dimensional (3-D) map of the surrounding environment is built

  18. Three-dimensional velocity obstacle method for UAV deconflicting maneuvers

    NARCIS (Netherlands)

    Jenie, Y.I.; Van Kampen, E.J.; De Visser, C.C.; Ellerbroek, J.; Hoekstra, J.M.

    2015-01-01

    Autonomous systems are required in order to enable UAVs to conduct self-separation and collision avoidance, especially for flights within the civil airspace system. A method called the Velocity Obstacle Method can provide the necessary situational awareness for UAVs in a dynamic environment, and can

  19. Measures for simulator evaluation of a helicopter obstacle avoidance system

    Science.gov (United States)

    Demaio, Joe; Sharkey, Thomas J.; Kennedy, David; Hughes, Micheal; Meade, Perry

    1993-01-01

    The U.S. Army Aeroflightdynamics Directorate (AFDD) has developed a high-fidelity, full-mission simulation facility for the demonstration and evaluation of advanced helicopter mission equipment. The Crew Station Research and Development Facility (CSRDF) provides the capability to conduct one- or two-crew full-mission simulations in a state-of-the-art helicopter simulator. The CSRDF provides a realistic, full field-of-regard visual environment with simulation of state-of-the-art weapons, sensors, and flight control systems. We are using the CSRDF to evaluate the ability of an obstacle avoidance system (OASYS) to support low altitude flight in cluttered terrain using night vision goggles (NVG). The OASYS uses a laser radar to locate obstacles to safe flight in the aircraft's flight path. A major concern is the detection of wires, which can be difficult to see with NVG, but other obstacles--such as trees, poles or the ground--are also a concern. The OASYS symbology is presented to the pilot on a head-up display mounted on the NVG (NVG-HUD). The NVG-HUD presents head-stabilized symbology to the pilot while allowing him to view the image intensified, out-the-window scene through the HUD. Since interference with viewing through the display is a major concern, OASYS symbology must be designed to present usable obstacle clearance information with a minimum of clutter.

  20. The Invisible Obstacle to Educational Equality: Gender Bias in Textbooks

    Science.gov (United States)

    Blumberg, Rae Lesser

    2008-01-01

    Gender bias in textbooks (GBIT) is a low-profile education issue, given the 72,000,000 children who still have no access to schooling, but this article argues that GBIT is: (1) an important, (2) near-universal, (3) remarkably uniform, (4) quite persistent but (5) virtually invisible obstacle on the road to gender equality in education--an obstacle…

  1. Misogyny, Women, and Obstacles to Tertiary Education: A Vile Situation.

    Science.gov (United States)

    Stalker, Joyce

    2001-01-01

    Interviews with 18 women enrolled in postsecondary education used a framework of misogyny to reinterpret barriers to their participation Resulting themes included women's role in maintaining the home as sanctuary, women needing constraint, and men's role as suppressors. Results suggest how a theory based in misogyny can explain obstacles to…

  2. Obstacles to defining the role of the mental health nurse.

    Science.gov (United States)

    Hamblet, C

    This article review 0s the available literature to find a definition of the primary function of the mental health nurse. A number of obstacles were encountered that would need to be tackled to achieve a consistency of thought across the profession.

  3. Numerical computation of a nonlocal double obstacle problem

    NARCIS (Netherlands)

    Bhowmik, S.K.

    2009-01-01

    We consider a nonlocal double obstacle problem. This type of problems comes in various biological and physical situations, e.g., in phase transition models. We focus on numerical approximations and fast computation of such a model. We start with considering piece-wise basis functions for spatial app

  4. Obstacle detection in range-image sequence for outdoor navigation

    Science.gov (United States)

    Garduno, M.; Vachon, Bertrand

    1994-08-01

    We deal with the conception of a perception system that's goal is to assist a mobile robot teleoperator by providing pertinent information about eventual obstacles appearing in the robot work space. This range image based perception system is to be embedded on a vehicle able to move at speeds up to 40 km/h in an outdoor environment. A method taking speed constraints into account is proposed. In the first step of this method, a segmentation algorithm is applied to the first range image scanned by the motionless robot to determine areas of interest. From these areas, distinctive attributes are computed and recorded as symbolic representations of each obstacle region. In the second and following steps, obstacles are localized in images scanned during robot motion. The difference between actual object position in the range image and its predicted value is used by an extended Kalman filter to correct the estimated robot configuration. A dynamic image segmentation using emergency and security criteria is carried out and new obstacles can now be detected from the range image and expressed in the robot coordinates system.

  5. Robot vision: obstacle-avoidance techniques for unmanned aerial vehicles

    NARCIS (Netherlands)

    Carloni, Raffaella; Lippiello, Vincenzo; D'auria, Massimo; Fumagalli, Matteo; Mersha, A.Y.; Stramigioli, Stefano; Sicilano, Bruno

    2013-01-01

    In this article, a vision-based technique for obstacle avoidance and target identification is combined with haptic feedback to develop a new teleoperated navigation system for underactuated aerial vehicles in unknown environments. A three-dimensional (3-D) map of the surrounding environment is built

  6. OBSTACLE PROBLEMS FOR SCALAR GINZBURG-LANDAU EQUATIONS

    Institute of Scientific and Technical Information of China (English)

    Ma Li; Su Ning

    2004-01-01

    In this note, we establish some estimates of solutions of the scalar Ginzburg-Landau equation and other nonlinear Laplacian equation Δu = f(x, u). This will give an estimate of the Hausdorff dimension for the free boundary of the obstacle problem.

  7. Special Semiotic Characters: What is an Obstacle-Sign?

    Directory of Open Access Journals (Sweden)

    Gary Genosko

    2013-11-01

    Full Text Available This article regains an understudied exposition from Michel Foucault’s Discipline and Punish concerning the nuanced semio-techniques that constitute a punitive city perfused with obstacle-signs. The semiotic import of these signs are explicated and then brought into contemporary focus with regard to their political efficacy in drunk-driving campaigns.

  8. Position and Obstacle Avoidance Algorithm in Robot Soccer

    Directory of Open Access Journals (Sweden)

    Awang H. Pratomo

    2010-01-01

    Full Text Available Problem statement: Robot soccer is an attractive domain for researchers and students working in the field of autonomous robots. However developing (coding, testing and debugging robots for such domain is a rather complex task. Approach: This study concentrated on developing position and obstacle avoidance algorithm in robot soccer. This part is responsible for realizing soccer skills such as movement, shoot and goal keeping. The formulation of position and obstacle avoidance was based on mathematical approach. This formula is to make sure that the movement of the robot is valid. Velocity of the robot was calculated to set the speed of the robot. The positioning theory including the coordination of the robot (x,y was used to find the obstacle and avoid it. Results: Some simulations and testing had been carried out to evaluate the usefulness of the proposed algorithms. The functions for shooting, movement and obstacle avoidance had been successfully implemented. Conclusion: The results showed its possibility could be used as strategy algorithms in real robot soccer competition.

  9. OBSTACLES TO BLUE-COLLAR PARTICIPATION IN ADULT EDUCATION.

    Science.gov (United States)

    LONDON, JACK; WENKERT, ROBERT

    WITH THE INCREASING LEISURE TIME OF BLUE-COLLAR WORKERS, CONCERN IS GROWING OVER THEIR LOW PARTICIPATION IN ADULT EDUCATION PROGRAMS. MYTHS ABOUT BLUE-COLLAR WORKERS WHICH STAND IN THEIR WAY INCLUDE--LOWER CLASS APATHY, INCAPABILITY OF SUSTAINED INTELLECTUAL EFFORT, AND LACK OF APPRECIATION OF THE VALUE OF EDUCATION. OBSTACLES INHERING IN SOCIAL…

  10. DNS and RANS Simulation of Dispersion Downstream of an Obstacle

    Science.gov (United States)

    2008-12-01

    DNS AND RANS SIMULATION OF DISPERSION DOWNSTREAM OF AN OBSTACLE Riccardo Rossi*, Gianluca Iaccarino** * Laboratorio di Termofluidodinamica...ORGANIZATION NAME(S) AND ADDRESS(ES) Laboratorio di Termofluidodinamica Computazionale, Seconda Facolt‘a di Ingegneria di Forl‘ý Universit‘a di Bologna

  11. The Obstacle Detection and Measurement Based on Machine Vision

    Directory of Open Access Journals (Sweden)

    Xitao Zheng

    2010-12-01

    Full Text Available To develop a quick obstacle detection and measurement algorithm for the image-based autonomous vehicle (AV or computer assisted driving system, this paper utilize the previous work of object detection to get the position of an obstacle and refocus windows on the selected target. Further calculation based on single camera will give the detailed measurement of the object, like the height, the distance to the vehicle, and possibly the width. It adopts a two camera system with different pitch angles, which can perform real-time monitoring for the front area of the vehicle with different coverage. This paper assumes that the vehicle will move at an even speed on a flat road, cameras will sample images at a given rate and the images will be analyzed simultaneously. Focus will be on the virtual window area of the image which is proved to be related to the distance to the object and speed of the vehicle. Counting of the blackened virtual sub-area can quickly find the existence of an obstacle and the obstacle area will be cut to get the interested parameter measurements for the object evaluation.

  12. Social Obstacles to Intercultural Competence in America's Language Classrooms

    Science.gov (United States)

    Fonseca-Greber, Bonnie

    2010-01-01

    In contrast with debates over language pedagogy or aptitude, this paper examines seven societal obstacles which impact the success of classroom language learning and the development of intercultural competence in American language classrooms. These include expectations for teacher preparation, language proficiency and target language use;…

  13. Principles of obstacle avoidance with a transfemoral prosthetic limb

    NARCIS (Netherlands)

    van Keeken, Helco G.; Vrieling, Aline H.; Hof, At L.; Postema, Klaas; Otten, Bert

    2012-01-01

    In this study, conditions that enable a prosthetic knee flexion strategy in transfemoral amputee subjects during obstacle avoidance were investigated. This study explored the hip torque principle and the static ground principle as object avoidance strategies. A prosthetic limb simulator device was u

  14. Face Recognition using Eigenfaces and Neural Networks

    Directory of Open Access Journals (Sweden)

    Mohamed Rizon

    2006-01-01

    Full Text Available In this study, we develop a computational model to identify the face of an unknown person’s by applying eigenfaces. The eigenfaces has been applied to extract the basic face of the human face images. The eigenfaces is then projecting onto human faces to identify unique features vectors. This significant features vector can be used to identify an unknown face by using the backpropagation neural network that utilized euclidean distance for classification and recognition. The ORL database for this investigation consists of 40 people with various 400 face images had been used for the learning. The eigenfaces including implemented Jacobi’s method for eigenvalues and eigenvectors has been performed. The classification and recognition using backpropagation neural network showed impressive positive result to classify face images.

  15. Social Psychological Face Perception: Why Appearance Matters

    Science.gov (United States)

    Zebrowitz, Leslie A.; Montepare, Joann M.

    2009-01-01

    We form first impressions from faces despite warnings not to do so. Moreover, there is considerable agreement in our impressions, which carry significant social outcomes. Appearance matters because some facial qualities are so useful in guiding adaptive behavior that even a trace of those qualities can create an impression. Specifically, the qualities revealed by facial cues that characterize low fitness, babies, emotion, and identity are overgeneralized to people whose facial appearance resembles the unfit (anomalous face overgeneralization), babies (babyface overgeneralization), a particular emotion (emotion face overgeneralization), or a particular identity (familiar face overgeneralization). We review studies that support the overgeneralization hypotheses and recommend research that incorporates additional tenets of the ecological theory from which these hypotheses are derived: the contribution of dynamic and multi-modal stimulus information to face perception; bidirectional relationships between behavior and face perception; perceptual learning mechanisms and social goals that sensitize perceivers to particular information in faces. PMID:20107613

  16. Culture shapes how we look at faces.

    Directory of Open Access Journals (Sweden)

    Caroline Blais

    Full Text Available BACKGROUND: Face processing, amongst many basic visual skills, is thought to be invariant across all humans. From as early as 1965, studies of eye movements have consistently revealed a systematic triangular sequence of fixations over the eyes and the mouth, suggesting that faces elicit a universal, biologically-determined information extraction pattern. METHODOLOGY/PRINCIPAL FINDINGS: Here we monitored the eye movements of Western Caucasian and East Asian observers while they learned, recognized, and categorized by race Western Caucasian and East Asian faces. Western Caucasian observers reproduced a scattered triangular pattern of fixations for faces of both races and across tasks. Contrary to intuition, East Asian observers focused more on the central region of the face. CONCLUSIONS/SIGNIFICANCE: These results demonstrate that face processing can no longer be considered as arising from a universal series of perceptual events. The strategy employed to extract visual information from faces differs across cultures.

  17. Nation, Face, and Identity: An Initial Investigation of National Face in East Asia

    Science.gov (United States)

    Chen, Rong; Hwang, Kwang-Kuo

    2016-01-01

    This research investigates a key concept in East Asia, face, and represents the first attempt to empirically examine the concept of face at the national level. Controlling for the level of national identification, Study 1 employed the scenario experiment method among samples of native Chinese and Taiwanese populations and revealed that national face exhibits patterns reverse of personal face. Using the experimental method, Study 2 replicated the findings of Study 1 and provided support for the different mechanisms underneath national face and personal face. Study 3 replicated the findings of Study 2 and additionally showed that national face exerts a significant inhibitory effect on face process. Findings are discussed in terms of possible implications for intergroup and international relations. Expanding on extant scholarship on face and across three studies with different experimental paradigms, this research turns our attention from face at the personal level to face at the national level by introducing the construct of national face and examining its manifestations in East Asia. The results advance our understanding of the psychological mechanism driving face concern in East Asia. They make a strong and unique case for the psychological existence of national face as an empirically distinct construct and an important psychological resource for East Asians. PMID:27774081

  18. The Body That Speaks: Recombining Bodies and Speech Sources in Unscripted Face-to-Face Communication

    OpenAIRE

    Alex Gillespie; Kevin Corti

    2016-01-01

    This article examines advances in research methods that enable experimental substitution of the speaking body in unscripted face-to-face communication. A taxonomy of six hybrid social agents is presented by combining three types of bodies (mechanical, virtual, and human) with either an artificial or human speech source. Our contribution is to introduce and explore the significance of two particular hybrids: (1) the cyranoid method that enables humans to converse face-to-face through the mediu...

  19. Classification of obstacle shape for generating walking path of humanoid robot

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chan Soo; Kim, Do Ik [Korea Institute of Science and Technology, Seoul (Korea, Republic of)

    2013-02-15

    To generate the walking path of a humanoid robot in an unknown environment, the shapes of obstacles around the robot should be detected accurately. However, doing so incurs a very large computational cast. Therefore this study proposes a method to classify the obstacle shape into three types: a shape small enough for the robot to go over, a shape planar enough for the robot foot to make contact with, and an uncertain shape that must be avoided by the robot. To classify the obstacle shape, first, the range and the number of the obstacles is detected. If an obstacle can make contact with the robot foot, the shape of an obstacle is accurately derived. If an obstacle has uncertain shape or small size, the shape of an obstacle is not detected to minimize the computational load. Experimental results show that the proposed algorithm efficiently classifies the shapes of obstacles around the robot in real time with low computational load.

  20. Problems Faced by Mexican Asylum Seekers in the United States

    Directory of Open Access Journals (Sweden)

    J. Anna Cabot

    2014-12-01

    Full Text Available Violence in Mexico rose sharply in response to President Felipe Calderón’s military campaign against drug cartels which began in late 2006. As a consequence, the number of Mexicans who have sought asylum in the United States has grown significantly. In 2013, Mexicans made up the second largest group of defensive asylum seekers (those in removal proceedings in the United States, behind only China (EOIR 2014b. Yet between 2008 and 2013, the grant rate for Mexican asylum seekers in immigration court fell from 23 percent to nine percent (EOIR 2013, 2014b. This paper examines—from the perspective of an attorney who represented Mexican asylum seekers on the US-Mexico border in El Paso, Texas—the reasons for low asylum approval rates for Mexicans despite high levels of violence in and flight from Mexico from 2008 to 2013. It details the obstacles faced by Mexican asylum seekers along the US-Mexico border, including placement in removal proceedings, detention, evidentiary issues, narrow legal standards, and (effectively judicial notice of country conditions in Mexico. The paper recommends that asylum seekers at the border be placed in affirmative proceedings (before immigration officials, making them eligible for bond. It also proposes increased oversight of immigration judges.

  1. Autonomous Navigation and Obstacle Avoidance of a Micro-bus

    Directory of Open Access Journals (Sweden)

    Carlos Fernández

    2013-04-01

    Full Text Available At present, the topic of automated vehicles is one of the most promising research areas in the field of Intelligent Transportation Systems (ITS. The use of automated vehicles for public transportation also contributes to reductions in congestion levels and to improvements in traffic flow. Moreover, electrical public autonomous vehicles are environmentally friendly, provide better air quality and contribute to energy conservation. The driverless public transportation systems, which are at present operating in some airports and train stations, are restricted to dedicated roads and exhibit serious trouble dynamically avoiding obstacles in the trajectory. In this paper, an electric autonomous mini-bus is presented. All datasets used in this article were collected during the experiments carried out in the demonstration event of the 2012 IEEE Intelligent Vehicles Symposium that took place in Alcalá de Henares (Spain. The demonstration consisted of a route 725 metres long containing a list of latitude-longitude points (waypoints. The mini-bus was capable of driving autonomously from one waypoint to another using a GPS sensor. Furthermore, the vehicle is provided with a multi-beam Laser Imaging Detection and Ranging (LIDAR sensor for surrounding reconstruction and obstacle detection. When an obstacle is detected in the planned path, the planned route is modified in order to avoid the obstacle and continue its way to the end of the mission. On the demonstration day, a total of 196 attendees had the opportunity to get a ride on the vehicles. A total of 28 laps were successfully completed in full autonomous mode in a private circuit located in the National Institute for Aerospace Research (INTA, Spain. In other words, the system completed 20.3 km of driverless navigation and obstacle avoidance.

  2. Facial emotion recognition, face scan paths, and face perception in children with neurofibromatosis type 1.

    Science.gov (United States)

    Lewis, Amelia K; Porter, Melanie A; Williams, Tracey A; Bzishvili, Samantha; North, Kathryn N; Payne, Jonathan M

    2017-05-01

    This study aimed to investigate face scan paths and face perception abilities in children with Neurofibromatosis Type 1 (NF1) and how these might relate to emotion recognition abilities in this population. The authors investigated facial emotion recognition, face scan paths, and face perception in 29 children with NF1 compared to 29 chronological age-matched typically developing controls. Correlations between facial emotion recognition, face scan paths, and face perception in children with NF1 were examined. Children with NF1 displayed significantly poorer recognition of fearful expressions compared to controls, as well as a nonsignificant trend toward poorer recognition of anger. Although there was no significant difference between groups in time spent viewing individual core facial features (eyes, nose, mouth, and nonfeature regions), children with NF1 spent significantly less time than controls viewing the face as a whole. Children with NF1 also displayed significantly poorer face perception abilities than typically developing controls. Facial emotion recognition deficits were not significantly associated with aberrant face scan paths or face perception abilities in the NF1 group. These results suggest that impairments in the perception, identification, and interpretation of information from faces are important aspects of the social-cognitive phenotype of NF1. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  3. On the Benefits of Stereo Graphics in Virtual Obstacle Avoidance Tasks

    DEFF Research Database (Denmark)

    Bærentzen, Jakob Andreas; Stenholt, Rasmus

    2014-01-01

    of an experiment to see if stereo makes any quantifiable, statistically significant difference in the ability to avoid collisions with virtual obstacles while navigating a 3-D space under constant acceleration. Our results indicate that for this particular application scenario, stereo does provide a significant......In virtual reality, stereo graphics is a very common way of increasing the level of perceptual realism in the visual part of the experience. However, stereo graphics comes at cost, both in technical terms and from a user perspective. In this paper, we present the preliminary results...

  4. An Aging Workforce: Employment Opportunities and Obstacles

    Directory of Open Access Journals (Sweden)

    Full Professor, Institute of Economic Sciences

    2013-05-01

    Full Text Available The last decade has witnessed significant changes in the structure of unemployment in the global labour market. This is corroborated by the fact that the global workforce is rapidly aging and the share of people aged 50 and over in the structure of the labour market is increasing. In line with this trend, unemployment issues should be considered as a global problem that cannot be fully resolved at the level of any individual country separately.The main objective of this paper is to throw some light on the aging workforce and the elderly population’s opportunity to realise their right to work and be treated equally with younger age groups. Hence, the paper simultaneously focuses on the age and gender discrimination of elderly population in terms of their employment prospects. The aim of our research is not only to point out certain stereotypes concerning the elderly labour force, but also to stress that unless preconditions for overcoming these stereotypes are created and employment opportunities are given to this segment of the labour force, full employment as an ultimate goal of global economic policy cannot be achieved. It is in accordance with these considerations that we offer a model to achieve this goal.

  5. Obstacles and opportunities in Chinese pharmaceutical innovation.

    Science.gov (United States)

    Ni, Jingyun; Zhao, Junrui; Ung, Carolina Oi Lam; Hu, Yuanjia; Hu, Hao; Wang, Yitao

    2017-03-24

    Global healthcare innovation networks nowadays have expanded beyond developed countries with many developing countries joining the force and becoming important players. China, in particular, has seen a significant increase in the number of innovative firms and research organizations stepping up to the global network in recent years. Nevertheless, the intense Research and Development input has not brought about the expectable output. While China is ascending at a great speed to a leading position worldwide in terms of Research and Development investment, scientific publications and patents, the innovation capabilities in the pharmaceutical sector remain weak. This study discusses the challenges and opportunities for pharmaceutical innovation in China. One hand, academic, industrial, institutional and financial constraints were found to be the major and inevitable barriers hindering the development of drug innovation. On the other hand, unique advantages had been observed which included growing pharmaceutical market, Research and Development funding, distinctive source, and international cooperation. The most important thing for China's pharmaceutical sector to leap forward is to break though innovation barriers and integrate own advantages into global value-chain of healthcare product development.

  6. Face Context Influences Local Part Processing: An ERP Study.

    Science.gov (United States)

    Zhang, Hong; Sun, Yaoru; Zhao, Lun

    2017-01-01

    Perception of face parts on the basis of features is thought to be different from perception of whole faces, which is more based on configural information. Face context is also suggested to play an important role in face processing. To investigate how face context influences the early-stage perception of facial local parts, we used an oddball paradigm that tested perceptual stages of face processing rather than recognition. We recorded the event-related potentials (ERPs) elicited by whole faces and face parts presented in four conditions (upright-normal, upright-thatcherised, inverted-normal and inverted-thatcherised), as well as the ERPs elicited by non-face objects (whole houses and house parts) with corresponding conditions. The results showed that face context significantly affected the N170 with increased amplitudes and earlier peak latency for upright normal faces. Removing face context delayed the P1 latency but did not affect the P1 amplitude prominently for both upright and inverted normal faces. Across all conditions, neither the N170 nor the P1 was modulated by house context. The significant changes on the N170 and P1 components revealed that face context influences local part processing at the early stage of face processing and this context effect might be specific for face perception. We further suggested that perceptions of whole faces and face parts are functionally distinguished.

  7. The hierarchical brain network for face recognition.

    Science.gov (United States)

    Zhen, Zonglei; Fang, Huizhen; Liu, Jia

    2013-01-01

    Numerous functional magnetic resonance imaging (fMRI) studies have identified multiple cortical regions that are involved in face processing in the human brain. However, few studies have characterized the face-processing network as a functioning whole. In this study, we used fMRI to identify face-selective regions in the entire brain and then explore the hierarchical structure of the face-processing network by analyzing functional connectivity among these regions. We identified twenty-five regions mainly in the occipital, temporal and frontal cortex that showed a reliable response selective to faces (versus objects) across participants and across scan sessions. Furthermore, these regions were clustered into three relatively independent sub-networks in a face-recognition task on the basis of the strength of functional connectivity among them. The functionality of the sub-networks likely corresponds to the recognition of individual identity, retrieval of semantic knowledge and representation of emotional information. Interestingly, when the task was switched to object recognition from face recognition, the functional connectivity between the inferior occipital gyrus and the rest of the face-selective regions were significantly reduced, suggesting that this region may serve as an entry node in the face-processing network. In sum, our study provides empirical evidence for cognitive and neural models of face recognition and helps elucidate the neural mechanisms underlying face recognition at the network level.

  8. Future practice risks: obstacles with opportunities.

    Science.gov (United States)

    Mallory, Thomas H

    2003-02-01

    The encouragement of a consumer-directed insurance market and the involvement of corporate America have led to a transformation of the healthcare system that will redefine patient expectations and the role of the physician. The expectation of a higher level of customer service, the role of electronic media, and an earnest regard for healthcare by the patient will impact the physician. Consumer-directed healthcare will call for a reprioritization, focusing on service, convenience, competency, quality, and low cost. Indifference to patient courtesies or failure to become involved in modern technology may cause the physician to be bypassed from this new healthcare system. As the business world integrates the business model into the medical profession, healthcare organizations will restructure themselves into well-organized business enterprises employing physicians. The singular physician may no longer be competitive with such business enterprises, leading to consolidation of organizations and a significant decision for the physician. The physician will have the unusual opportunity to either remain exclusively a medical professional or to also venture into the business world as an equity investor, participating in financial growth possibilities of those medical practice organizations that are for-profit. With the emergence of these new equity models of healthcare, the primary focus will be on profit, production, and service efficiencies. It is the responsibility of the physician to maintain professionalism and the commitment to quality and appropriateness of patient care. However, at the same time, the physician has the unique opportunity to participate in the distribution, economics, and subsequent financial profit of healthcare. The medical experience of the physician, coupled with business acumen, will be an unbeatable combination.

  9. Brain and face: communicating signals of health in the left and right sides of the face.

    Science.gov (United States)

    Reis, V A; Zaidel, D W

    2001-01-01

    In human communication and mate selection the appearance of health sends signals regarding biological fitness. We compared the appearance of health in the sides of the face to previous results on left-right facial asymmetry in the appearance of beauty (1). The stimuli were created by aligning the left and right sides of the face each with its own mirror image. Here, participants viewed 38 pairs of left-left and right-right faces and judged which member of the pair looked healthier. No significant interaction emerged between decision (health vs attractiveness) and face side. Rather, in women's faces right-right was significantly more healthy and attractive than left-left, while in men's faces there was no significant left-right difference. In biology and evolution, health and beauty are closely linked and the findings here confirm this relationship in human faces.

  10. Oracle ADF Faces cookbook

    CERN Document Server

    Gawish, Amr

    2014-01-01

    This is a cookbook that covers more than 80 different recipes to teach you about different aspects of Oracle ADF Faces. It follows a practical approach and covers how to build your components for reuse in different applications. This book will also help you in tuning the performance of your ADF Faces application. If you are an ADF developer who wants to harness the power of Oracle ADF Faces to create exceptional user interfaces and reactive applications, this book will provide you with the recipes needed to do just that. You will not need to be familiar with Oracle ADF Faces, but you should be

  11. Blood Pressure and Electrocardiographic changes During Face ...

    African Journals Online (AJOL)

    The cardiovascular responses in non-exercising and regularly exercising young ... temperature) with breath-hold significantly increased BP, QRS amplitude, PR interval, ... Face immersion thus caused a significant reduction in heart rate (HR).

  12. DWT BASED HMM FOR FACE RECOGNITION

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A novel Discrete Wavelet Transform (DWT) based Hidden Markov Module (HMM) for face recognition is presented in this letter. To improve the accuracy of HMM based face recognition algorithm, DWT is used to replace Discrete Cosine Transform (DCT) for observation sequence extraction. Extensive experiments are conducted on two public databases and the results show that the proposed method can improve the accuracy significantly, especially when the face database is large and only few training images are available.

  13. Kinematic effect of Nintendo WiiTM sports program exercise on obstacle gait in elderly women with falling risk

    Science.gov (United States)

    Jung, Dae-In; Ko, Dae-Sik; Jeong, Mi-Ae

    2015-01-01

    [Purpose] This study evaluated the changes in balance ability and obstacle gait after lumbar stabilization exercise and Nintendo WiiTM Sports in elderly at risk for falls. [Subjects and Methods] Twenty-four elderly women with at risk for falls were randomly divided into the control, lumbar stabilization exercise, and Nintendo Wii Sports groups. Static balance was measured by the Berg Balance Scale and functional reach test, dynamic balance by the timed up-and-go test, and obstacle negotiation function by crossing velocity and maximum vertical heel clearance. [Results] Both the lumbar stabilization exercise and Nintendo Wii Sports groups showed significant improvements in obstacle negotiation function after the exercise compared to the control group. Berg Balance Scale and functional reach test scores were greater in the lumbar stabilization exercise group, while the timed up-and-go test time was significantly better in the Nintendo Wii Sports groups. [Conclusion] Lumbar stabilization exercises and Nintendo Wii Sports improve falling related balance and obstacle negotiation function in elderly women at risk for falls. PMID:26157228

  14. Kinematic effect of Nintendo Wii(TM) sports program exercise on obstacle gait in elderly women with falling risk.

    Science.gov (United States)

    Jung, Dae-In; Ko, Dae-Sik; Jeong, Mi-Ae

    2015-05-01

    [Purpose] This study evaluated the changes in balance ability and obstacle gait after lumbar stabilization exercise and Nintendo Wii(TM) Sports in elderly at risk for falls. [Subjects and Methods] Twenty-four elderly women with at risk for falls were randomly divided into the control, lumbar stabilization exercise, and Nintendo Wii Sports groups. Static balance was measured by the Berg Balance Scale and functional reach test, dynamic balance by the timed up-and-go test, and obstacle negotiation function by crossing velocity and maximum vertical heel clearance. [Results] Both the lumbar stabilization exercise and Nintendo Wii Sports groups showed significant improvements in obstacle negotiation function after the exercise compared to the control group. Berg Balance Scale and functional reach test scores were greater in the lumbar stabilization exercise group, while the timed up-and-go test time was significantly better in the Nintendo Wii Sports groups. [Conclusion] Lumbar stabilization exercises and Nintendo Wii Sports improve falling related balance and obstacle negotiation function in elderly women at risk for falls.

  15. The Effects of Face Inversion and Face Race on the P100 ERP.

    Science.gov (United States)

    Colombatto, Clara; McCarthy, Gregory

    2016-11-29

    Research about the neural basis of face recognition has investigated the timing and anatomical substrates of different stages of face processing. Scalp-recorded ERP studies of face processing have focused on the N170, an ERP with a peak latency of ∼170 msec that has long been associated with the initial structural encoding of faces. However, several studies have reported earlier ERP differences related to faces, suggesting that face-specific processes might occur before N170. Here, we examined the influence of face inversion and face race on the timing of face-sensitive scalp-recorded ERPs by examining neural responses to upright and inverted line-drawn and luminance-matched White and Black faces in a sample of White participants. We found that the P100 ERP evoked by inverted faces was significantly larger than that evoked by upright faces. Although this inversion effect was statistically significant at 100 msec, the inverted-upright ERP difference peaked at 138 msec, suggesting that it might represent an activity in neural sources that overlap with P100. Inverse modeling of the inversion effect difference waveform suggested possible neural sources in pericalcarine extrastriate visual cortex and lateral occipito-temporal cortex. We also found that the inversion effect difference wave was larger for White faces. These results are consistent with behavioral evidence that individuals process the faces of their own races more configurally than faces of other races. Taken together, the inversion and race effects observed in the current study suggest that configuration influences face processing by at least 100 msec.

  16. Student Success in Face-to-Face and Online Sections of Biology Courses at a Community College in East Tennessee

    Science.gov (United States)

    Garman, Deanna Essington

    2012-01-01

    The purpose of this quantitative study was to determine if there were significant differences in student success in face-to-face and online biology courses as categorized by gender, major, and age; and as measured by lecture grades, lab grades, and final course grades. The data used for analyses included data from 170 face-to-face sections and 127…

  17. Preparation of students with disabilities to graduate into professions in the South African context of higher learning: Obstacles and opportunities

    Directory of Open Access Journals (Sweden)

    Sibonokuhle Ndlovu

    2016-02-01

    Full Text Available Background: Persons with disabilities continue to be excluded from professions in South Africa despite legislation on non-discrimination and equity. Objectives: We sought to identify both the opportunities and obstacles that students with disabilities face in professional degrees. Method: Selected texts from the South African and international literature were analysed and synthesised. Results: Students with disabilities are afforded opportunities to graduate into professions through the current climate of transformation, inclusion and disability policies, various support structures and funding. These opportunities are mitigated by obstacles at both the higher education site and at the workplace. At university, they may experience difficulties in accessing the curriculum, disability units may be limited in the support they can offer, policies may not be implemented, funding is found to be inadequate and the built environment may be inaccessible. Fieldwork poses additional obstacles in terms of public transport which is not accessible to students with disabilities; a lack of higher education support extended to the field sites, and buildings not designed for access by people with disabilities. At both sites, students are impacted by negative attitudes and continued assumptions that disability results from individual deficit, rather than exclusionary practices and pressures. Conclusion: It is in the uniqueness of professional preparation, with its high demands of both theory and practice that poses particular obstacles for students with disabilities. We argue for the development of self-advocacy for students with disabilities, ongoing institutional and societal transformation and further research into the experiences of students with disabilities studying for professional degrees.

  18. Probing the Feature Map for Faces in Visual Search

    Directory of Open Access Journals (Sweden)

    Hua Yang

    2011-05-01

    Full Text Available Controversy surrounds the mechanisms underlying the pop-out effect for faces in visual search. Is there a feature map for faces? If so, does it rely on the categorical distinction between faces and nonfaces, or on image-level face semblance? To probe the feature map, we compared search efficiency for faces, and nonface stimuli with high, low, and no face semblance. First, subjects performed a visual search task with objects as distractors. Only faces popped-out. Moreover, search efficiency for nonfaces correlated with image-level face semblance of the target. In a second experiment, faces were used as distractors but nonfaces did not pop-out. Interestingly, search efficiency for nonfaces was not modulated by face semblance, although searching for a face among faces was particularly difficult, reflecting a categorical boundary between nonfaces and faces. Finally, inversion and contrast negation significantly interacted with the effect of face semblance, ruling out the possibility that search efficiency solely depends on low-level features. Our study supports a parallel search for faces that is perhaps preattentive. Like other features (color, orientation etc., there appears to be a continuous face feature map for visual search. Our results also suggest that this map may include both image-level face semblance and face categoricity.

  19. Social judgments from faces.

    Science.gov (United States)

    Todorov, Alexander; Mende-Siedlecki, Peter; Dotsch, Ron

    2013-06-01

    People make rapid and consequential social judgments from minimal (non-emotional) facial cues. There has been rapid progress in identifying the perceptual basis of these judgments using data-driven, computational models. In contrast, our understanding of the neural underpinnings of these judgments is rather limited. Meta-analyses of neuroimaging studies find a wide range of seemingly inconsistent responses in the amygdala that co-vary with social judgments from faces. Guided by computational models of social judgments, these responses can be accounted by positing that the amygdala (and posterior face selective regions) tracks face typicality. Atypical faces, whether positively or negatively evaluated, elicit stronger responses in the amygdala. We conclude with the promise of data-driven methods for modeling neural responses to social judgments from faces.

  20. Individual differences in holistic processing predict face recognition ability.

    Science.gov (United States)

    Wang, Ruosi; Li, Jingguang; Fang, Huizhen; Tian, Moqian; Liu, Jia

    2012-02-01

    Why do some people recognize faces easily and others frequently make mistakes in recognizing faces? Classic behavioral work has shown that faces are processed in a distinctive holistic manner that is unlike the processing of objects. In the study reported here, we investigated whether individual differences in holistic face processing have a significant influence on face recognition. We found that the magnitude of face-specific recognition accuracy correlated with the extent to which participants processed faces holistically, as indexed by the composite-face effect and the whole-part effect. This association is due to face-specific processing in particular, not to a more general aspect of cognitive processing, such as general intelligence or global attention. This finding provides constraints on computational models of face recognition and may elucidate mechanisms underlying cognitive disorders, such as prosopagnosia and autism, that are associated with deficits in face recognition.

  1. FOREWORD: Special section on electromagnetic characterization of buried obstacles

    Science.gov (United States)

    Lesselier, Dominique; Chew, Weng Cho

    2004-12-01

    This Inverse Problems special section on electromagnetic characterization of buried obstacles contains a selection of 14 invited papers, involving 41 authors and 19 research groups worldwide. (Though this section consists of invited papers, the standard refereeing procedures of Inverse Problems have been rigorously observed.) We do not claim to have reached all the high-level researchers in the field, but we believe that we have made a fair attempt. As illustrated by the variety of contributions included, the aim of this special section is to address theoretical and practical inversion problems (and the solutions thereof) that arise in the field of electromagnetic characterization of obstacles (artificial or natural) buried on the Earth or in planetary subsoil. Civil and military engineering, archaeological and environmental issues are typically among those within the scope of the investigation. An example is the characterization of a single (or multiple) obstacle(s) located near the interface or at shallow depths via electromagnetic means operating within relevant frequency bands. However, we also welcomed novel and thought-provoking investigations, even though their direct application to the real world, or even to laboratory-controlled settings, may still be far off. Within this general mathematical and applied framework, the submitted papers focused on a combination of theoretical, computational and experimental developments. They either reviewed the most recent advances in a particular area of research or were an original and specialized contribution. Let us now take the opportunity to remind the readers that this special section harks back (in addition to sharing some common contributors) to two special sections already published in the journal which possessed the same flavour of wave-field inversion and its many applications. They were `Electromagnetic imaging and inversion of the Earth's subsurface', which was published in October 2000 (volume 16, issue 5

  2. Scattering of gravity waves in subcritical flows over an obstacle

    CERN Document Server

    Robertson, Scott; Parentani, Renaud

    2016-01-01

    We numerically study the scattering coefficients of linear water waves on stationary flows above a localized obstacle. We compare the scattering on trans- and subcritical flows, and then focus on the latter which have been used in recent analog gravity experiments. The main difference concerns the magnitude of the mode amplification: whereas transcritical flows display a large amplification (which is generally in good agreement with the Hawking prediction), this effect is heavily suppressed in subcritical flows. This is due to the transmission across the obstacle for frequencies less than some critical value. As a result, subcritical flows display high- and low-frequency behaviors separated by a narrow band around the critical frequency. In the low-frequency regime, transmission of long wavelengths is accompanied by non-adiabatic scattering into short wavelengths, whose spectrum is approximately linear in frequency. By contrast, in the high-frequency regime, no simple description seems to exist. In particular...

  3. Opportunities and obstacles for good work in nursing.

    Science.gov (United States)

    Miller, Joan F

    2006-09-01

    Good work in nursing is work that is scientifically effective as well as morally and socially responsible. The purpose of this study was to examine variables that sustain good work among entering nurses (with one to five years of experience) and experienced professional nurses despite the obstacles they encounter. In addition to role models and mentors, entering and experienced nurses identified team work, cohesiveness and shared values as levers for good work. These nurses used prioritization, team building and contemplative practices to overcome obstacles. Entering professional nurses tended to avoid conflict in the work setting. Experienced nurses reported forming teams of decision makers who share similar values to resolve conflict. These findings have implications for nurse education and nursing practice. Reflection on the importance of values and virtue in sustaining good work is important. Entering professional nurses should be encouraged to seek positive role models and reflect on the lessons that can be learned from experienced exemplary nurses.

  4. Overcoming Obstacles to Colour-Kinematics Duality at Two Loops

    CERN Document Server

    Mogull, Gustav

    2015-01-01

    The discovery of colour-kinematics duality has allowed great progress in our understanding of the UV structure of gravity. However, it has proven difficult to find numerators which satisfy colour-kinematics duality in certain cases. We discuss obstacles to building a set of such numerators in the context of the five-gluon amplitude with all helicities positive at two loops. We are able to overcome the obstacles by adding more loop momentum to our numerator to accommodate tension between the values of certain cuts and the symmetries of certain diagrams. At the same time, we maintain control over the size of our ansatz by identifying a highly constraining but desirable symmetry property of our master numerator. The resulting numerators have twelve powers of loop momenta rather than the seven one would expect from the Feynman rules.

  5. Influence of swimming strategy on microorganism separation by asymmetric obstacles

    CERN Document Server

    Berdakin, I; Moshchalkov, V V; Venken, L; Dierckx, S; Vanderleyden, S J; Silhanek, A V; Condat, C A; Marconi, V I

    2013-01-01

    It has been shown that a nanoliter chamber separated by a wall of asymmetric obstacles can lead to an inhomogeneous distribution of self-propelled microorganisms. Although it is well established that this rectification effect arises from the interaction between the swimmers and the non-centrosymmetric pillars, here we demonstrate numerically that its efficiency is strongly dependent on the detailed dynamics of the individual microorganism. In particular, for the case of run-and-tumble dynamics, the distribution of run lengths, the rotational diffusion and the partial preservation of run orientation memory through a tumble are important factors when computing the rectification efficiency. In addition, we optimize the geometrical dimensions of the asymmetric pillars in order to maximize the swimmer concentration and we illustrate how it can be used for sorting by swimming strategy in a long array of parallel obstacles.

  6. Solution of Contact Problems for Nonlinear Gao Beam and Obstacle

    Directory of Open Access Journals (Sweden)

    J. Machalová

    2015-01-01

    Full Text Available Contact problem for a large deformed beam with an elastic obstacle is formulated, analyzed, and numerically solved. The beam model is governed by a nonlinear fourth-order differential equation developed by Gao, while the obstacle is considered as the elastic foundation of Winkler’s type in some distance under the beam. The problem is static without a friction and modeled either using Signorini conditions or by means of normal compliance contact conditions. The problems are then reformulated as optimal control problems which is useful both for theoretical aspects and for solution methods. Discretization is based on using the mixed finite element method with independent discretization and interpolations for foundation and beam elements. Numerical examples demonstrate usefulness of the presented solution method. Results for the nonlinear Gao beam are compared with results for the classical Euler-Bernoulli beam model.

  7. Animal-Inspired Sensing for Autonomously Climbing or Avoiding Obstacles

    Directory of Open Access Journals (Sweden)

    William A. Lewinger

    2009-01-01

    Full Text Available The way that natural systems navigate their environments with agility, intelligence and efficiency is an inspiration to engineers. Biological attributes such as modes of locomotion, sensory modalities, behaviours and physical appearance have been used as design goals. While methods of locomotion allow robots to move through their environment, the addition of sensing, perception and decision making are necessary to perform this task with autonomy. This paper contrasts how the addition of two separate sensing modalities – tactile antennae and non-contact sensing – and a low-computation, capable microcontroller allow a biologically abstracted mobile robot to make insect-inspired decisions when encountering a shelflike obstacle, navigating a cluttered environment without collision and seeking vision-based goals while avoiding obstacles.

  8. Overcoming Obstacles: Opportunities of academically talented women in Iran

    Directory of Open Access Journals (Sweden)

    Shahla Alborzi, Ph.D

    2008-03-01

    Full Text Available The aim of the present research was to study the lifetime obstacles and opportunities of academically successful women working at Iran universities. Successful female academics in Iran are concerned about the social and personal barriers to pursuing successful careers in academia. These women continually work to overcome these barriers in an ongoing process called overcoming obstacles. This basic social process has five stages: perceiving inequality, conflicting, dissolving, empowering and acting purposefully. Throughout the process, these women have first become aware of gender inequities and then worked towards overcoming them using self-motivation properties and support from external sources such as family, mentors and colleagues. This substantive theory, though rooted in a specific country with a strong male dominated social structure, is applicable to all societies as they continue to work towards equitable access to high-level career opportunities.

  9. Obstacle-avoiding robot with IR and PIR motion sensors

    Science.gov (United States)

    Ismail, R.; Omar, Z.; Suaibun, S.

    2016-10-01

    Obstacle avoiding robot was designed, constructed and programmed which may be potentially used for educational and research purposes. The developed robot will move in a particular direction once the infrared (IR) and the PIR passive infrared (PIR) sensors sense a signal while avoiding the obstacles in its path. The robot can also perform desired tasks in unstructured environments without continuous human guidance. The hardware was integrated in one application board as embedded system design. The software was developed using C++ and compiled by Arduino IDE 1.6.5. The main objective of this project is to provide simple guidelines to the polytechnic students and beginners who are interested in this type of research. It is hoped that this robot could benefit students who wish to carry out research on IR and PIR sensors.

  10. Scattering theory of walking droplets in the presence of obstacles

    CERN Document Server

    Dubertrand, Rémy; Schlagheck, Peter; Vandewalle, Nicolas; Bastin, Thierry; Martin, John

    2016-01-01

    We aim to describe a droplet bouncing on a vibrating bath. Due to Faraday instability a surface wave is created at each bounce and serves as a pilot wave of the droplet. This leads to so called walking droplets or walkers. Since the seminal experiment by {\\it Couder et al} [Phys. Rev. Lett. {\\bf 97}, 154101 (2006)] there have been many attempts to accurately reproduce the experimental results. Here we present a simple and highly versatile model inspired from quantum mechanics. We propose to describe the trajectories of a walker using a Green function approach. The Green function is related to Helmholtz equation with Neumann boundary conditions on the obstacle(s) and outgoing conditions at infinity. For a single slit geometry our model is exactly solvable and reproduces some general features observed experimentally. It stands for a promising candidate to account for the presence of any boundaries in the walkers'dynamics.

  11. Scattering theory of walking droplets in the presence of obstacles

    Science.gov (United States)

    Dubertrand, Rémy; Hubert, Maxime; Schlagheck, Peter; Vandewalle, Nicolas; Bastin, Thierry; Martin, John

    2016-11-01

    We aim to describe a droplet bouncing on a vibrating bath using a simple and highly versatile model inspired from quantum mechanics. Close to the Faraday instability, a long-lived surface wave is created at each bounce, which serves as a pilot wave for the droplet. This leads to so called walking droplets or walkers. Since the seminal experiment by Couder et al (2006 Phys. Rev. Lett. 97 154101) there have been many attempts to accurately reproduce the experimental results.We propose to describe the trajectories of a walker using a Green function approach. The Green function is related to the Helmholtz equation with Neumann boundary conditions on the obstacle(s) and outgoing boundary conditions at infinity. For a single-slit geometry our model is exactly solvable and reproduces some general features observed experimentally. It stands for a promising candidate to account for the presence of arbitrary boundaries in the walker’s dynamics.

  12. Driven Brownian transport through arrays of symmetric obstacles.

    Science.gov (United States)

    Ghosh, P K; Hänggi, P; Marchesoni, F; Martens, S; Nori, F; Schimansky-Geier, L; Schmid, G

    2012-01-01

    We numerically investigate the transport of a suspended overdamped Brownian particle which is driven through a two-dimensional rectangular array of circular obstacles with finite radius. Two limiting cases are considered in detail, namely, when the constant drive is parallel to the principal or the diagonal array axes. This corresponds to studying the Brownian transport in periodic channels with reflecting walls of different topologies. The mobility and diffusivity of the transported particles in such channels are determined as functions of the drive and the array geometric parameters. Prominent transport features, like negative differential mobilities, excess diffusion peaks, and unconventional asymptotic behaviors, are explained in terms of two distinct lengths, the size of single obstacles (trapping length), and the lattice constant of the array (local correlation length). Local correlation effects are further analyzed by continuously rotating the drive between the two limiting orientations. © 2012 American Physical Society

  13. Distance Determination Method for Normally Distributed Obstacle Avoidance of Mobile Robots in Stochastic Environments

    Directory of Open Access Journals (Sweden)

    Jinhong Noh

    2016-04-01

    Full Text Available Obstacle avoidance methods require knowledge of the distance between a mobile robot and obstacles in the environment. However, in stochastic environments, distance determination is difficult because objects have position uncertainty. The purpose of this paper is to determine the distance between a robot and obstacles represented by probability distributions. Distance determination for obstacle avoidance should consider position uncertainty, computational cost and collision probability. The proposed method considers all of these conditions, unlike conventional methods. It determines the obstacle region using the collision probability density threshold. Furthermore, it defines a minimum distance function to the boundary of the obstacle region with a Lagrange multiplier method. Finally, it computes the distance numerically. Simulations were executed in order to compare the performance of the distance determination methods. Our method demonstrated a faster and more accurate performance than conventional methods. It may help overcome position uncertainty issues pertaining to obstacle avoidance, such as low accuracy sensors, environments with poor visibility or unpredictable obstacle motion.

  14. Distance Determination Method for Normally Distributed Obstacle Avoidance of Mobile Robots in Stochastic Environments

    Directory of Open Access Journals (Sweden)

    Jinhong Noh

    2016-04-01

    Full Text Available Obstacle avoidance methods require knowledge of the distance between a mobile robot and obstacles in the environment. However, in stochastic environments, distance determination is difficult because objects have position uncertainty. The purpose of this paper is to determine the distance between a robot and obstacles represented by probability distributions. Distance determination for obstacle avoidance should consider position uncertainty, computational cost and collision probability. The proposed method considers all of these conditions, unlike conventional methods. It determines the obstacle region using the collision probability density threshold. Furthermore, it defines a minimum distance function to the boundary of the obstacle region with a Lagrange multiplier method. Finally, it computes the distance numerically. Simulations were executed in order to compare the performance of the distance determination methods. Our method demonstrated a faster and more accurate performance than conventional methods. It may help overcome position uncertainty issues pertaining to obstacle avoidance, such as low accuracy sensors, environments with poor visibility or unpredictable obstacle motion.

  15. 75 FR 60304 - Standard Instrument Approach Procedures, and Takeoff Minimums and Obstacle Departure Procedures...

    Science.gov (United States)

    2010-09-30

    .... John M. Allen, Director, Flight Standards Service. Adoption of the Amendment Accordingly, pursuant to..., Takeoff Minimums and Obstacle DP, Amdt 2 Minden, LA, Minden-Webster, Takeoff Minimums and Obstacle...

  16. Anger Superiority in Single-Face Judgements

    Directory of Open Access Journals (Sweden)

    Hiroshi Ashida

    2011-05-01

    Full Text Available We investigated “anger superiority” in single-face judgements. Angry, or threatening, faces are easier to find than smiling ones (Hansen & Hansen, 1988 but it remains controversial whether this reflects emotional effects on the basis of the whole face or rather perceptual effects on the basis of parts. We sought this question differently from most previous studies that used the visual search paradigm. We presented a picture of angry, smiling, or neutral face (extracted from ATR DB99 database that has been confirmed for emotional strength either to the left or to the right of the fixation mark, which was followed by a mask, and the participants were asked to make a forced-choice judgement of anger or smile. The results showed that neutral faces were significantly biased towards anger with upright presentation but not with inverted presentation. Angry and smiling faces were judged equally well with upright presentation, while there was notable reduction of correct responses only for angry face with inverted presentation. Difference between hemifields was not clear. The results suggest that angry faces are judged on the basis of configural processing of the whole face, while smiling faces may be judged more locally on the basis of parts.

  17. 2D Dubins Path in Environments with Obstacle

    Directory of Open Access Journals (Sweden)

    Dongxiao Yang

    2013-01-01

    Full Text Available We recapitulate the achievement about the Dubins path as well as some precise proofs which are important but omitted by Dubins. Then we prove that the shortest path (R*-geodesic in environments with an obstacle consists of no more than five segments, each of which is either an arc or a straight line. To obtain such R*-geodesic, an effective algorithm is presented followed by a numerical simulation as verification.

  18. Obstacles to labour companionship at Bamalete Lutheran hospital Ramotswa : Botswana

    OpenAIRE

    2012-01-01

    M.Cur. Obstacles to labour companionship at Bamalete Lutheran Hospital (BLH) in Botswana are discussed. There is an underutilization of labour companionship in the BLH maternity ward despite several efforts that have been made to introduce labour companionship. Labour companionship is a rare exception in the BLH labour ward. Why is labour companionship underutilized at Bamalete Lutheran Hospital and what could be done to promote labour companions? An explorative, descriptive, qualitative, ...

  19. [Obstacles and Opportunities for the Psychotherapeutic Treatment of Asylum Seekers].

    Science.gov (United States)

    Mewes, Ricarda; Kowarsch, Lea; Reinacher, Hanna; Nater, Urs M

    2016-09-01

    Introduction: The number of refugees and asylum seekers in Germany is high. Presumably, the need for psychotherapeutic care is high in this group. However, this need stands in contrast to a lack of a specialized and widespread provision of such care. Registered psychotherapists could help to partially reduce this gap. The present study aimed at learning more about the expected or experienced obstacles and opportunities of registered psychotherapists in regard to the psychotherapeutic treatment of asylum seekers in Germany. Methods: 198 Hessian registered psychotherapists (40% of all contacted persons) from the administrative districts Marburg-Biedenkopf, Gießen, Lahn-Dill-Kreis, Schwalm-Eder-Kreis und Waldeck-Frankenberg completed a questionnaire. The questionnaire assessed their views of different possible obstacles and advantages regarding the psychotherapy of asylum seekers, as well as possibilities to improve one's own willingness to provide such a treatment. Results: The majority of the participating psychotherapists indicated a modest willingness to provide psychotherapy for asylum seekers. One third had already treated (on average 1-2) asylum seekers. The strongest obstacles were the application of translators, the high formal costs, and the insecurity regarding the reimbursement of therapy sessions. Possible cultural divergences, being afraid of difficult themes, or a potentially reduced adherence of asylum seekers were not seen as meaningful obstacles. Becoming familiar with another culture and new experiences were seen as main advantages of psychotherapy with an asylum seeker. Conclusion: The psychotherapeutic care of asylum seekers could possibly be improved through the exchange of information among psychotherapists and with the responsible local administrative organizations. Moreover, administrative districts could mainly improve the situation by providing help with finding adequate translators, facilitate the formal costs, and secure the reimbursement

  20. Micro-Controller Based Obstacle Avoiding Autonomous Robot

    Directory of Open Access Journals (Sweden)

    Subhranil Som

    2014-06-01

    Full Text Available Main aim of this paperwork is to study development of the obstacle avoiding spy robot, which can be operated manually as per the operator wants to take control of the robot himself, it also can be autonomous in its actions while intelligently moving itself by detecting the obstacles in front of it by the help of the obstacle detectable circuit. The robot is in form of a vehicle mounted with a web cam, which acquires and sends video as per the robots eye view to a TV or PC via a TV tuner card. The microcontroller chip ATMEGA 328 present on the microcontroller board ARDUINO controls the movements of the robot. In manual operating conditions the user will have a radio transmitter (tx via which the user will send signal to the radio receiver (rx present inside the robot which accordingly will pass on the signal to the microcontroller board, and as per the coding of the signal signatures burnt inside the microcontroller chip the robot will complete its movements. In Autonomous operating conditions the user will have no control on the robot that is the robot cannot be operated via any external controls, it will only function as per the data received from the obstacle detection circuits to the microcontroller which will make the robot motors move accordingly as per the code written in it. The idea is to make a robot to tackle the hostage situations & cope up with the worst conditions, which can be quiet a matter of risk to be handled by human being.

  1. An intelligent guidance and control system for ship obstacle avoidance

    OpenAIRE

    Harris, C J; Hong, X.; Wilson, P. A.

    1999-01-01

    An intelligent guidance and control system using a neurofuzzy network multistep ahead predictor model is introduced and applied to ship obstacle avoidance, which uses only observed input/output data generated by on board and external sensors, and a data fusion algorithm to generate the desired waypoints. A simple and effective waypoint guidance scheme based on line-of-sight is derived for a data based ship model. A neurofuzzy network predictor, based on using rudder deflection angle for the c...

  2. Rotation Sets of Billiards with N Obstacles on a Torus

    OpenAIRE

    Alsheekhhussain, Zainab

    2016-01-01

    For billiards with $N$ obstacles on a torus, we study the behavior of specific kind of its trajectories, \\emph{the so called admissible trajectories}. Using the methods developed in \\cite{1}, we prove that the \\emph{admissible rotation set} is convex, and the periodic trajectories of admissible type are dense in the admissible rotation set. In addition, we show that the admissible rotation set is a proper subset of the general rotation set.

  3. Public hospitals: the legal obstacles of entering into joint ventures.

    Science.gov (United States)

    Miller, J N

    1986-03-01

    Public hospitals, as public entities, are limited in many of their activities by state constitutions and statutes. One area where activity can be particularly limited is the joint venture. Constitutional and statutory limitations can influence several aspects of the joint venture: scope of activities, geographic boundaries, authority to enter into joint ventures, gift of public funds prohibition, and stock ownership. Therefore, public hospitals must be aware of possible legal obstacles and carefully consider their options.

  4. AUV (REDERMOR) obstacle detection and avoidance experimental evaluation

    OpenAIRE

    Quidu, Isabelle; Hétet, Alain; Dupas, Yann; Lefèvre, Stéphanie

    2007-01-01

    International audience; Autonomous Underwater Vehicles (AUV) are expected to perform survey missions in both known and unknown environments. While the primary mission of an AUV is data collection, generally achieved with a sidescan sonar or a multibeam echosounder, another key task is to guaranty its own security. This paper deals with the problem of obstacle detection and avoidance by means of a forward looking sonar (FLS) mounted on the GESMA Redermor experimental AUV.

  5. Engaging basic scientists in translational research: identifying opportunities, overcoming obstacles

    Directory of Open Access Journals (Sweden)

    Hobin Jennifer A

    2012-04-01

    Full Text Available Abstract This report is based on the Federation of American Societies for Experimental Biology’s symposium, “Engaging basic Scientists in Translational Research: Identifying Opportunities, Overcoming Obstacles,” held in Chevy Chase, MD, March 24–25, 2011. Meeting participants examined the benefits of engaging basic scientists in translational research, the challenges to their participation in translational research, and the roles that research institutions, funding organizations, professional societies, and scientific publishers can play to address these challenges.

  6. A Method to Identify Flight Obstacles on Digital Surface Model

    Institute of Scientific and Technical Information of China (English)

    ZHAO Min; LIN Xinggang; SUN Shouyu; WANG Youzhi

    2005-01-01

    In modern low-altitude terrain-following guidance, a constructing method of the digital surface model (DSM) is presented in the paper to reduce the threat to flying vehicles of tall surface features for safe flight. The relationship between an isolated obstacle size and the intervals of vertical- and cross-section in the DSM model is established. The definition and classification of isolated obstacles are proposed, and a method for determining such isolated obstacles in the DSM model is given. The simulation of a typical urban district shows that when the vertical- and cross-section DSM intervals are between 3 m and 25 m, the threat to terrain-following flight at low-altitude is reduced greatly, and the amount of data required by the DSM model for monitoring in real time a flying vehicle is also smaller. Experiments show that the optimal results are for an interval of 12.5 m in the vertical- and cross-sections in the DSM model, with a 1:10 000 DSM scale grade.

  7. BIM-BASED INDOOR PATH PLANNING CONSIDERING OBSTACLES

    Directory of Open Access Journals (Sweden)

    M. Xu

    2017-09-01

    Full Text Available At present, 87 % of people’s activities are in indoor environment; indoor navigation has become a research issue. As the building structures for people’s daily life are more and more complex, many obstacles influence humans’ moving. Therefore it is essential to provide an accurate and efficient indoor path planning. Nowadays there are many challenges and problems in indoor navigation. Most existing path planning approaches are based on 2D plans, pay more attention to the geometric configuration of indoor space, often ignore rich semantic information of building components, and mostly consider simple indoor layout without taking into account the furniture. Addressing the above shortcomings, this paper uses BIM (IFC as the input data and concentrates on indoor navigation considering obstacles in the multi-floor buildings. After geometric and semantic information are extracted, 2D and 3D space subdivision methods are adopted to build the indoor navigation network and to realize a path planning that avoids obstacles. The 3D space subdivision is based on triangular prism. The two approaches are verified by the experiments.

  8. Can hippocampal neurites and growth cones climb over obstacles?

    Science.gov (United States)

    Lien, Thuy Linh; Ban, Jelena; Tormen, Massimo; Migliorini, Elisa; Grenci, Gianluca; Pozzato, Alessandro; Torre, Vincent

    2013-01-01

    Guidance molecules, such as Sema3A or Netrin-1, can induce growth cone (GC) repulsion or attraction in the presence of a flat surface, but very little is known of the action of guidance molecules in the presence of obstacles. Therefore we combined chemical and mechanical cues by applying a steady Netrin-1 stream to the GCs of dissociated hippocampal neurons plated on polydimethylsiloxane (PDMS) surfaces patterned with lines 2 µm wide, with 4 µm period and with a height varying from 100 to 600 nm. GC turning experiments performed 24 hours after plating showed that filopodia crawl over these lines within minutes. These filopodia do not show staining for the adhesion marker Paxillin. GCs and neurites crawl over lines 100 nm high, but less frequently and on a longer time scale over lines higher than 300 nm; neurites never crawl over lines 600 nm high. When neurons are grown for 3 days over patterned surfaces, also neurites can cross lines 300 nm and 600 nm high, grow parallel to and on top of these lines and express Paxillin. Axons - selectively stained with SMI 312 - do not differ from dendrites in their ability to cross these lines. Our results show that highly motile structures such as filopodia climb over high obstacle in response to chemical cues, but larger neuronal structures are less prompt and require hours or days to climb similar obstacles.

  9. A Comparison of Fluidic and Physical Obstacles for Deflagration-to-Detonation Transition

    Science.gov (United States)

    2010-12-16

    Bruun, H. H., Hot - Wire Anemometry , Oxford University Press, Oxford, 1995. 13. Naples, A., Yu, S.T.J., Hoke, J., Busby, K., Schauer, F., “Pressure...downstream of both obstacles with hot -film anemometry during non-reacting steady flow, show a conservative trend that a fluidic obstacle produces...downstream of both obstacles with hot -film anemometry during non-reacting steady flow, show a conservative trend that a fluidic obstacle produces

  10. Distance Determination Method for Normally Distributed Obstacle Avoidance of Mobile Robots in Stochastic Environments

    OpenAIRE

    Jinhong Noh; Ukyoul Huh

    2016-01-01

    Obstacle avoidance methods require knowledge of the distance between a mobile robot and obstacles in the environment. However, in stochastic environments, distance determination is difficult because objects have position uncertainty. The purpose of this paper is to determine the distance between a robot and obstacles represented by probability distributions. Distance determination for obstacle avoidance should consider position uncertainty, computational cost and collision probability. The pr...

  11. Self-face recognition in social context.

    Science.gov (United States)

    Sugiura, Motoaki; Sassa, Yuko; Jeong, Hyeonjeong; Wakusawa, Keisuke; Horie, Kaoru; Sato, Shigeru; Kawashima, Ryuta

    2012-06-01

    The concept of "social self" is often described as a representation of the self-reflected in the eyes or minds of others. Although the appearance of one's own face has substantial social significance for humans, neuroimaging studies have failed to link self-face recognition and the likely neural substrate of the social self, the medial prefrontal cortex (MPFC). We assumed that the social self is recruited during self-face recognition under a rich social context where multiple other faces are available for comparison of social values. Using functional magnetic resonance imaging (fMRI), we examined the modulation of neural responses to the faces of the self and of a close friend in a social context. We identified an enhanced response in the ventral MPFC and right occipitoparietal sulcus in the social context specifically for the self-face. Neural response in the right lateral parietal and inferior temporal cortices, previously claimed as self-face-specific, was unaffected for the self-face but unexpectedly enhanced for the friend's face in the social context. Self-face-specific activation in the pars triangularis of the inferior frontal gyrus, and self-face-specific reduction of activation in the left middle temporal gyrus and the right supramarginal gyrus, replicating a previous finding, were not subject to such modulation. Our results thus demonstrated the recruitment of a social self during self-face recognition in the social context. At least three brain networks for self-face-specific activation may be dissociated by different patterns of response-modulation in the social context, suggesting multiple dynamic self-other representations in the human brain.

  12. Study on Obstacles to Continuous Cropping of Vegetables and Soil Remediation Technology

    Institute of Scientific and Technical Information of China (English)

    Pingsheng FAN; Gang CHEN; Deli XU; Weimin FENG; Yuyu LU; Anqin GUAN

    2016-01-01

    Firstly,this paper analyzes the cause of obstacles to continuous cropping of vegetables,and then introduces the soil ecological remediation technology used for overcoming obstacles to continuous cropping of vegetables. Finally,this paper analyzes the effect of applying soil ecological remediation technology in overcoming obstacles to continuous cropping of vegetables.

  13. A study on model fidelity for model predictive control-based obstacle avoidance in high-speed autonomous ground vehicles

    Science.gov (United States)

    Liu, Jiechao; Jayakumar, Paramsothy; Stein, Jeffrey L.; Ersal, Tulga

    2016-11-01

    This paper investigates the level of model fidelity needed in order for a model predictive control (MPC)-based obstacle avoidance algorithm to be able to safely and quickly avoid obstacles even when the vehicle is close to its dynamic limits. The context of this work is large autonomous ground vehicles that manoeuvre at high speed within unknown, unstructured, flat environments and have significant vehicle dynamics-related constraints. Five different representations of vehicle dynamics models are considered: four variations of the two degrees-of-freedom (DoF) representation as lower fidelity models and a fourteen DoF representation with combined-slip Magic Formula tyre model as a higher fidelity model. It is concluded that the two DoF representation that accounts for tyre nonlinearities and longitudinal load transfer is necessary for the MPC-based obstacle avoidance algorithm in order to operate the vehicle at its limits within an environment that includes large obstacles. For less challenging environments, however, the two DoF representation with linear tyre model and constant axle loads is sufficient.

  14. [The most important obstacles of the development of Hungarian psychiatry].

    Science.gov (United States)

    Kalmár, Sándor

    2015-06-01

    A quarter of a century ago the change of the political system in Hungary precipitated a serious value-crisis and caused a lot of harmful effects in nurturing and the development of psychiatry. The author establishes that the attack against psychiatry is more intensive than previously but neither the education and health management nor the psychiatric leadership could cope with these difficulties. It can't be denied that the foundation of lifelong mental health begins in the early life years and about 75% of the first Mental Disorder manifests in adolescence and youth. We are not able to ensure the special rights of every child according to the Hungarian Constitution and the Declaration of the Rights of the Child by the United Nations. The large inequalities within the country, the lack of paramount mental education and nurturing, the lack of essential, consistent eternal values, the lack of required psychiatric care system are huge obstacles of the development of healthy individual and leads to self-destructive behaviour and several, serious physical and mental disorders. The purpose of the author is to call psychiatrists' attention to the main obstacles of the development of Hungarian Psychiatric Care System. The main obstacles of the present psychiatric care system: 1. Unclarified notions, confusion of ideas. 2. Somatic, neurologic, mental, cultural-social and spiritual ignorance. 3. Lack of organization in Mental Education and Psychiatric Care System. 4. Value-crisis in our society despite the fact that the "Council of Wise Men" created a "Scale of the Essential Consistent Eternal Values" for the Hungarian Education System in 2008. 5. Lack of mental health prevention both in education system and health care system. There is no teaching of hygiene lessons in the Hungarian schools. 6. Negligence and selfishness among the population. 7. Disinterest among competent authorities. 8. Leaving the most important possibilities out of consideration. The author establishes

  15. Self-Reported Obstacles to Regular Dental Care among Information Technology Professionals

    Science.gov (United States)

    Reddy, L. Swetha; Reddy, B. Srikanth; Kulkarni, Suhas; Reddy, M. Padma; Satyanarayana, D.; Baldava, Pavan

    2016-01-01

    Introduction Good oral health is important for an individual as well as social well-being. Occupational stress and work exhaustion in Information Technology (IT) professionals may influence the oral health and oral health related quality of life. Aim To assess and compare self-reported obstacles for regular dental care and dental visits among IT professionals based on age, gender, dental insurance and working days per week. Materials and Methods A cross-sectional study was conducted among 1,017 IT professionals to assess the self-reported obstacles to regular oral health care in Hyderabad city, Telangana, India. The Dental Rejection of Innovation Scale (DRI-S) was employed in this study. Comparison between means of DRI-S based on variables was done using t-test and ANOVA. The association between variables and DRI-S was determined using Chi-square test. Results A total of 1017 participants comprising of 574 (56%) males and 443 (44%) females participated in the study. As age increased, a significant increase in mean DRI-S scores was seen for total and individual domains except for the “Situational” domain wherein higher mean score (9.42±2.5; p=0.0006) was observed among 30–39 years age group. Even though females reported higher mean scores for total and individual domains when compared to males, nevertheless significant difference was seen only for total (p=0.03) and “Lack of Knowledge” (p=0.001) domain. Conclusion Self-reported obstacles to regular dental care was more with increasing age, increased number of working days per week, irregular dental visits and absence of dental insurance facility. PMID:27891475

  16. Handbook of Face Recognition

    CERN Document Server

    Li, Stan Z

    2011-01-01

    This highly anticipated new edition provides a comprehensive account of face recognition research and technology, spanning the full range of topics needed for designing operational face recognition systems. After a thorough introductory chapter, each of the following chapters focus on a specific topic, reviewing background information, up-to-date techniques, and recent results, as well as offering challenges and future directions. Features: fully updated, revised and expanded, covering the entire spectrum of concepts, methods, and algorithms for automated face detection and recognition systems

  17. Face-to-face or Face-to-screen? Undergraduates’ opinions and test performance in classroom versus online learning

    Directory of Open Access Journals (Sweden)

    Nenagh eKemp

    2014-11-01

    Full Text Available As electronic communication becomes increasingly common, and as students juggle study, work, and family life, many universities are offering their students more flexible learning opportunities. Classes once delivered face-to-face are often replaced by online activities and discussions. However, there is little research comparing students’ experience and learning in these two modalities. The aim of this study was to compare undergraduates’ preference for, and academic performance on, class material and assessment presented online versus in traditional classrooms. Psychology students (N = 71 at an Australian university completed written exercises, a class discussion, and a written test on two academic topics. The activities for one topic were conducted face-to-face, and the other online, with topics counterbalanced across two groups. The results showed that students preferred to complete activities face-to-face rather than online, but there was no significant difference in their test performance in the two modalities. In their written responses, students expressed a strong preference for class discussions to be conducted face-to-face, reporting that they felt more engaged, and received more immediate feedback, than in online discussion. A follow-up study with a separate group confirmed that although students appreciated the convenience of completing written activities online in their own time, they also strongly preferred to discuss course content with peers in the classroom rather than online. It is concluded that online and face-to-face activities can lead to similar levels of academic performance, but that students would rather do written activities online but engage in discussion in person. Course developers could aim to structure classes so that students can benefit from both the flexibility of online learning, and the greater engagement experienced in face-to-face discussion.

  18. 3D detection of obstacle distribution in walking guide system for the blind

    Science.gov (United States)

    Yoon, Myoung-Jong; Yu, Kee-Ho

    2007-12-01

    In this paper, the concept of a walking guide system with tactile display is introduced, and experiments of 3-D obstacle detection and tactile perception are carried out and analyzed. The algorithm of 3-D obstacle detection and the method of mapping the generated obstacle map and the tactile display device for the walking guide system are proposed. The experiment of the 3-D detection for the obstacle position using ultrasonic sensors is performed and estimated. Some design guidelines for a tactile display device that can display obstacle distribution is discussed.

  19. Females excel at basic face perception.

    Science.gov (United States)

    McBain, Ryan; Norton, Dan; Chen, Yue

    2009-02-01

    Females are generally better than males at recognizing facial emotions. However, it is not entirely clear whether and in what way females may also excel at non-affective face recognition. Here, we tested males and females on two perceptual face recognition tasks that involved only neutral expressions: detection and identity discrimination. On face detection (Experiment 1), females were significantly more accurate than males in detecting upright faces. This gender difference was reduced during inverted face detection, and not present during tree detection, suggesting that the magnitude of the gender difference for performance co-varies with the extent to which face processing mechanisms are involved. On facial identity discrimination (Experiment 2), females again outperformed males, particularly when face images were masked by visual noise, or the delay between comparison face images was extended from 0.5 to 3s. These results reveal a female advantage in processing face-specific information and underscore the role of perceptual factors in socially relevant gender differences.

  20. Face imagery is based on featural representations.

    Science.gov (United States)

    Lobmaier, Janek S; Mast, Fred W

    2008-01-01

    The effect of imagery on featural and configural face processing was investigated using blurred and scrambled faces. By means of blurring, featural information is reduced; by scrambling a face into its constituent parts configural information is lost. Twenty-four participants learned ten faces together with the sound of a name. In following matching-to-sample tasks participants had to decide whether an auditory presented name belonged to a visually presented scrambled or blurred face in two experimental conditions. In the imagery condition, the name was presented prior to the visual stimulus and participants were required to imagine the corresponding face as clearly and vividly as possible. In the perception condition name and test face were presented simultaneously, thus no facilitation via mental imagery was possible. Analyses of the hit values showed that in the imagery condition scrambled faces were recognized significantly better than blurred faces whereas there was no such effect for the perception condition. The results suggest that mental imagery activates featural representations more than configural representations.

  1. Contextual modulation of biases in face recognition.

    Directory of Open Access Journals (Sweden)

    Fatima Maria Felisberti

    Full Text Available BACKGROUND: The ability to recognize the faces of potential cooperators and cheaters is fundamental to social exchanges, given that cooperation for mutual benefit is expected. Studies addressing biases in face recognition have so far proved inconclusive, with reports of biases towards faces of cheaters, biases towards faces of cooperators, or no biases at all. This study attempts to uncover possible causes underlying such discrepancies. METHODOLOGY AND FINDINGS: Four experiments were designed to investigate biases in face recognition during social exchanges when behavioral descriptors (prosocial, antisocial or neutral embedded in different scenarios were tagged to faces during memorization. Face recognition, measured as accuracy and response latency, was tested with modified yes-no, forced-choice and recall tasks (N = 174. An enhanced recognition of faces tagged with prosocial descriptors was observed when the encoding scenario involved financial transactions and the rules of the social contract were not explicit (experiments 1 and 2. Such bias was eliminated or attenuated by making participants explicitly aware of "cooperative", "cheating" and "neutral/indifferent" behaviors via a pre-test questionnaire and then adding such tags to behavioral descriptors (experiment 3. Further, in a social judgment scenario with descriptors of salient moral behaviors, recognition of antisocial and prosocial faces was similar, but significantly better than neutral faces (experiment 4. CONCLUSION: The results highlight the relevance of descriptors and scenarios of social exchange in face recognition, when the frequency of prosocial and antisocial individuals in a group is similar. Recognition biases towards prosocial faces emerged when descriptors did not state the rules of a social contract or the moral status of a behavior, and they point to the existence of broad and flexible cognitive abilities finely tuned to minor changes in social context.

  2. Drag generation by interfacial waves at an inversion/thermocline in non-hydrostatic flow past an axisymmetric obstacle

    Science.gov (United States)

    Teixeira, Miguel A. C.; Paci, Alexandre; Belleudy, Anne

    2017-04-01

    waves for relatively low Froude numbers, a dispersive 'Kelvin ship wake' for nearly critical Froude numbers, and divergent waves for high Froude numbers. The interface displacement existing directly over/beneath the lee of the obstacle has a minimum height/depth that is significantly correlated with the value of the drag. This is not surprising, given that this asymmetric displacement is associated with a lee-side pressure deficit that is ultimately responsible for the drag force in this flow configuration.

  3. Comparison of face Recognition Algorithms on Dummy Faces

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    Aruni Singh

    2012-09-01

    Full Text Available In the age of rising crime face recognition is enormously important in the contexts of computer vision, psychology, surveillance, fraud detection, pattern recognition, neural network, content based video processing, etc. Face is a non intrusive strong biometrics for identification and hence criminals always try to hide their facial organs by different artificial means such as plastic surgery, disguise and dummy. The availability of a comprehensive face database is crucial to test the performance of these face recognition algorithms. However, while existing publicly-available face databases contain face images with a wide variety of poses, illumination, gestures and face occlusions but there is no dummy face database is available in public domain. The contributions of this research paper are: i Preparation of dummy face database of 110 subjects ii Comparison of some texture based, feature based and holistic face recognition algorithms on that dummy face database, iii Critical analysis of these types of algorithms on dummy face database.

  4. The Major Obstacles of Correct Pronunciation: for Lithuanians Learning Spanish and for Spanish Learning Lithuanian

    Directory of Open Access Journals (Sweden)

    Loreta Alešiūnaitė

    2012-06-01

    Full Text Available When a person starts learning a new foreign language and tries to speak to a native speaker, it is a common situation when he/she is asked to repeat (sometimes more than once because the listener does not understand the speaker‘s pronunciation. As a consequence, the speaker’s confidence in his/her language competence is shaken as well as motivation for the use of this foreign language. This situation shows the importance of correct pronunciation which is one of the significant components of successful foreign language learning. Recently, the learning of Spanish and Lithuanian as foreign languages has become increasingly popular in Kaunas. From 2009 a quarter of LUHS foreign students are Spanish students, and Spanish is the first most chosen from 26 of those taught as a second foreign language at VMU. During the analysis of Spanish and Lithuanian phonetic similarities and differences, the main purpose is to discuss, compare and identify the major obstacles in pronunciation for Lithuanians learning Spanish and for Spanish students learning Lithuanian. The experimental mirror principle reveals the main obstacles to correct pronunciation which indicate the cases where Spanish students make pronunciation mistakes in the Lithuanian language, and, respectively, those cases are the same where the pronunciation obstacles for Lithuanians speaking Spanish arise. Learning of phonetics is one of the most important parts of communicative competence – that is why it is recommended to pay attention to the orthoepy in foreign languages and begin to develop pronunciation from the very first levels of language learning, because the positive results appear in the long run and after much practice.

  5. Obstacle avoidance during human walking: learning rate and cross-modal transfer.

    Science.gov (United States)

    Erni, T; Dietz, V

    2001-07-01

    1. The aim of this study was to investigate the significance of specific afferent information during motor learning. Blindfolded subjects stepped over an obstacle on a treadmill while different stimuli (acoustic (ACU), somatosensory (SOM) and light flash (LED)) signalled the approaching obstacle. The effect of the above stimuli was then evaluated and compared to full vision (VIS) locomotion. In the non-visual conditions feedback information about the performance was provided by an acoustic signal. 2. Using each of the different stimuli for information the level of subject performance was assessed by noting foot clearance and analysing both leg muscle electromyographic activity and movement trajectories during three successive runs. Each of these runs consisted of 100 steps over the obstacle. 3. The best performance at the onset of the first run was achieved during the VIS condition. When the VIS condition (run 1 + 2) was followed by ACU or SOM information or when the ACU condition (run 1 + 2) was followed by LED, little cross-modal transfer (CMT) occurred, i.e. adaptation in run 3 started again at a low level of performance. In contrast, if adaptation started with ACU stimuli followed by SOM stimuli, almost full CMT occurred. The absolute level of performance achieved after the second or third runs was similar in the VIS and non-VIS conditions. 4. In conclusion, the course of motor learning depends on specific afferent information, and feedforward control has a special influence on the performance only at the onset of the experiment but not on the rate of learning. The fact that little CMT occurs from visual to non-visual stimuli and from ACU to LED suggests that visual afferent input is processed in a different way to non-visual stimuli.

  6. Aquatic obstacle training improves freezing of gait in Parkinson's disease patients: a randomized controlled trial.

    Science.gov (United States)

    Zhu, Zhizhong; Yin, Miaomiao; Cui, Liling; Zhang, Ying; Hou, Weijia; Li, Yaqing; Zhao, Hua

    2017-06-01

    Our aim was to evaluate the effect of aquatic obstacle training on balance parameters in comparison with a traditional aquatic therapy in patients with Parkinson's disease. A randomized single-blind controlled trial. Outpatients in the rehabilitation department. A total of 46 patients with Parkinson's disease in Hoehn-Yahr stage 2-3. Participants were randomly assigned to (1) aquatic therapy or (2) obstacle aquatic therapy. All participants undertook aquatic therapy for 30 minutes, five times per week for six weeks. The Freezing of Gait Questionnaire, Functional Reach Test, Timed Up and Go test and Berg Balance Scale were assessed at baseline, posttreatment and at six-month follow-up. Both groups of patients had improved primary outcomes after the training program. A between-group comparison of the changes revealed that obstacle aquatic therapy was significantly higher for the Freezing of Gait Questionnaire (after treatment: 8.7 ± 3.3 vs 6.2 ± 2.1, P = 0.004; posttest: 7.7 ± 3.1 vs 5.3 ± 2.0, P = 0.003) and Timed Up and Go test (after treatment: 17.1 ± 2.9 vs 13.8 ± 1.9, P aquatic therapy in this protocol seems to be more effective than traditional protocols for gait and balance in patients with Parkinson's disease, and the effect lasts for six months.

  7. Is Face Distinctiveness Gender Based?

    Science.gov (United States)

    Baudouin, Jean-Yves; Gallay, Mathieu

    2006-01-01

    Two experiments were carried out to study the role of gender category in evaluations of face distinctiveness. In Experiment 1, participants had to evaluate the distinctiveness and the femininity-masculinity of real or artificial composite faces. The composite faces were created by blending either faces of the same gender (sexed composite faces,…

  8. Guided Online or Face-to-Face Cognitive Behavioral Treatment for Insomnia: A Randomized Wait-List Controlled Trial.

    Science.gov (United States)

    Lancee, Jaap; van Straten, Annemieke; Morina, Nexhmedin; Kaldo, Viktor; Kamphuis, Jan H

    2016-01-01

    To compare the efficacy of guided online and individual face-to-face cognitive behavioral treatment for insomnia (CBT-I) to a wait-list condition. A randomized controlled trial comparing three conditions: guided online; face-to-face; wait-list. Posttest measurements were administered to all conditions, along with 3- and 6-mo follow-up assessments to the online and face-to-face conditions. Ninety media-recruited participants meeting the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria for insomnia were randomly allocated to either guided online CBT-I (n = 30), individual face-to-face CBT-I (n = 30), or wait-list (n = 30). At post-assessment, the online (Cohen d = 1.2) and face-to-face (Cohen d = 2.3) intervention groups showed significantly larger treatment effects than the wait-list group on insomnia severity (insomnia severity index). Large treatment effects were also found for the sleep diary estimates (except for total sleep time), and anxiety and depression measures (for depression only in the face-to-face condition). Face-to-face treatment yielded a statistically larger treatment effect (Cohen d = 0.9) on insomnia severity than the online condition at all time points. In addition, a moderate differential effect size favoring face-to-face treatment emerged at the 3- and 6-mo follow-up on all sleep diary estimates. Face-to-face treatment further outperformed online treatment on depression and anxiety outcomes. These data show superior performance of face-to-face treatment relative to online treatment. Yet, our results also suggest that online treatment may offer a potentially cost-effective alternative to and complement face-to-face treatment. Clinicaltrials.gov, NCT01955850. A commentary on this article appears in this issue on page 13. © 2016 Associated Professional Sleep Societies, LLC.

  9. Item Nonresponse in Face-to-Face Interviews with Children

    Directory of Open Access Journals (Sweden)

    Haunberger Sigrid

    2014-09-01

    Full Text Available This study examined item nonresponse and its respondent and interviewer correlates by means of a population-based, panel survey of children aged 8 to 11 who were surveyed using standardised, face-to-face interviews. Using multilevel, logistic analyses with cross-level interactions, this article aims to examine which effects of item nonresponse are subject to children as respondents or to the interviewers and the interview setting. Depending on the type of question, we found different effects for respondent and interviewer variables, as well as interaction effects between child age/interviewer age as well as child gender/interviewer gender. However, interviewer variance is for the most part not significant.

  10. Trustworthy-looking face meets brown eyes.

    Directory of Open Access Journals (Sweden)

    Karel Kleisner

    Full Text Available We tested whether eye color influences perception of trustworthiness. Facial photographs of 40 female and 40 male students were rated for perceived trustworthiness. Eye color had a significant effect, the brown-eyed faces being perceived as more trustworthy than the blue-eyed ones. Geometric morphometrics, however, revealed significant correlations between eye color and face shape. Thus, face shape likewise had a significant effect on perceived trustworthiness but only for male faces, the effect for female faces not being significant. To determine whether perception of trustworthiness was being influenced primarily by eye color or by face shape, we recolored the eyes on the same male facial photos and repeated the test procedure. Eye color now had no effect on perceived trustworthiness. We concluded that although the brown-eyed faces were perceived as more trustworthy than the blue-eyed ones, it was not brown eye color per se that caused the stronger perception of trustworthiness but rather the facial features associated with brown eyes.

  11. Trustworthy-looking face meets brown eyes.

    Science.gov (United States)

    Kleisner, Karel; Priplatova, Lenka; Frost, Peter; Flegr, Jaroslav

    2013-01-01

    We tested whether eye color influences perception of trustworthiness. Facial photographs of 40 female and 40 male students were rated for perceived trustworthiness. Eye color had a significant effect, the brown-eyed faces being perceived as more trustworthy than the blue-eyed ones. Geometric morphometrics, however, revealed significant correlations between eye color and face shape. Thus, face shape likewise had a significant effect on perceived trustworthiness but only for male faces, the effect for female faces not being significant. To determine whether perception of trustworthiness was being influenced primarily by eye color or by face shape, we recolored the eyes on the same male facial photos and repeated the test procedure. Eye color now had no effect on perceived trustworthiness. We concluded that although the brown-eyed faces were perceived as more trustworthy than the blue-eyed ones, it was not brown eye color per se that caused the stronger perception of trustworthiness but rather the facial features associated with brown eyes.

  12. Forward imaging for obstacle avoidance using ultrawideband synthetic aperture radar

    Science.gov (United States)

    Nguyen, Lam H.; Wong, David C.; Stanton, Brian; Smith, Gregory

    2003-09-01

    In support of the Army vision for increased mobility, survivability, and lethality, we are investigating the use of ultra-wideband (UWB) synthetic aperture radar (SAR) technology to enhance unmanned ground vehicle missions. The ability of UWB radar technology to detect objects concealed by foilage could provide an important obstacle avoidance capability for robotic vehicles. This would improve the speed and maneuverability of these vehicles and consequently increase the probability of survivability of U.S. forces. This technology would address the particular challenges that confront robotic vehicles such as large rocks hidden in tall grass and voids such as ditches and bodies of water. ARL has designed and constructed an instrumentation-grade low frequency, UWB synthetic aperture radar for evaluation of the target signatures and underlying phenomenology of stationary tactical targets concealed by foilage and objects buried in the ground. The radar (named BoomSAR) is installed in teh basekt of a 30-ton boom lift and can be operated while the entire boom lift is driven forward slowly, with the boom arm extended as high as 45 m to generate a synthetic aperture. In this paper, we investigate the potential use of the UWB radar in the forward imaging configuration. The paper describes the forward imaging radar and test setup at Aberdeen Proving Ground, Maryland. We present imagery of "positive" obstacles such as trees, fences, wires, mines, etc., as well as "negative" obstacles such as ditches. Imagery of small targets such as plastic mines is also included. We provide eletromagnetic simulations of forward SAR imagery of plastic mines and compare that to the measurement data.

  13. Childhood fever management program for Korean pediatric nurses: A comparison between blended and face-to-face learning method.

    Science.gov (United States)

    Jeong, Yong Sun; Kim, Jin Sun

    2014-01-01

    A blended learning can be a useful learning strategy to improve the quality of fever and fever management education for pediatric nurses. This study compared the effects of a blended and face-to-face learning program on pediatric nurses' childhood fever management, using theory of planned behavior. A nonequivalent control group pretest-posttest design was used. A fever management education program using blended learning (combining face-to-face and online learning components) was offered to 30 pediatric nurses, and 29 pediatric nurses received face-to-face education. Learning outcomes did not significantly differ between the two groups. However, learners' satisfaction was higher for the blended learning program than the face-to-face learning program. A blended learning pediatric fever management program was as effective as a traditional face-to-face learning program. Therefore, a blended learning pediatric fever management-learning program could be a useful and flexible learning method for pediatric nurses.

  14. Individual differences in adaptive coding of face identity are linked to individual differences in face recognition ability.

    Science.gov (United States)

    Rhodes, Gillian; Jeffery, Linda; Taylor, Libby; Hayward, William G; Ewing, Louise

    2014-06-01

    Despite their similarity as visual patterns, we can discriminate and recognize many thousands of faces. This expertise has been linked to 2 coding mechanisms: holistic integration of information across the face and adaptive coding of face identity using norms tuned by experience. Recently, individual differences in face recognition ability have been discovered and linked to differences in holistic coding. Here we show that they are also linked to individual differences in adaptive coding of face identity, measured using face identity aftereffects. Identity aftereffects correlated significantly with several measures of face-selective recognition ability. They also correlated marginally with own-race face recognition ability, suggesting a role for adaptive coding in the well-known other-race effect. More generally, these results highlight the important functional role of adaptive face-coding mechanisms in face expertise, taking us beyond the traditional focus on holistic coding mechanisms.

  15. Knowledge retention in capstone experiences: An analysis of online and face-to-face courses

    Directory of Open Access Journals (Sweden)

    John P. Girard

    2016-12-01

    Full Text Available This research chronicles the development of a capstone experience by a regional comprehensive university. The process began with a multi-year project during which the faculty annually reviewed the results with a view to determining if the class provided the deep learning culminating experiences anticipated. A major measure of success was the desire to replicate the deep learning common in face-to-face classes in the online environment. The results of 166 students were analyzed, 82 online and 84 face-to-face, to determine if a difference existed. A one-way ANOVA tested the score differences among 10 sections and determined the students’ scores did not differ significantly. Finally, a two-sample t-test between proportions determined that there was not a significant difference between the online and face-to-face students with respect to the level of assessment scores earned. Given that online and face-to-face students demonstrate the same level of knowledge, does this beg the question, what value does face-to-face class time offer?

  16. Vision-based recursive estimation of rotorcraft obstacle locations

    Science.gov (United States)

    Leblanc, D. J.; Mcclamroch, N. H.

    1992-01-01

    The authors address vision-based passive ranging during nap-of-the-earth (NOE) rotorcraft flight. They consider the problem of estimating the relative location of identifiable features on nearby obstacles, assuming a sequence of noisy camera images and imperfect measurements of the camera's translation and rotation. An iterated extended Kalman filter is used to provide recursive range estimation. The correspondence problem is simplified by predicting and tracking each feature's image within the Kalman filter framework. Simulation results are presented which show convergent estimates and generally successful feature point tracking. Estimation performance degrades for features near the optical axis and for accelerating motions. Image tracking is also sensitive to angular rate.

  17. Observation of three dimensional optical rogue waves through obstacles

    Energy Technology Data Exchange (ETDEWEB)

    Leonetti, Marco, E-mail: marco.leonetti@roma1.infn.it [Center for Life Nano Science@Sapienza, Istituto Italiano di Tecnologia, Viale Regina Elena, 291 00161 Roma (RM) (Italy); Conti, Claudio [ISC-CNR and Department of Physics, University Sapienza, P.le Aldo Moro 5, I-00185 Roma (Italy)

    2015-06-22

    We observe three-dimensional rogue waves in the speckle distribution of a spatially modulated optical beam. Light is transmitted beyond a partially reflecting obstacle generating optical rogue waves at a controlled position in the shadow of the barrier. When the barrier transmits only 0.07% of the input laser power, we observe the mostly localized event. These results demonstrate that an optimum amount of spatial non-homogeneity maximizes the probability of a gigantic event while the technique we exploit enables to control light behind a fully reflective wall.

  18. The Main Obstacles to Improve English Reading Speed

    Institute of Scientific and Technical Information of China (English)

    YANG Yu-rong

    2016-01-01

    With the globalization of economy, English has become a universal language, which makes learning of English increas-ingly important in many non-English-speaking countries. In order to learn the language well, reading should be attached ade-quate importance. Reading ability, as a basic requirement in learning a foreign language, can be developed by doing comprehen-sion exercises. The key to improve reading lies in reading speed. The faster you read, the more you are able to grasp the main point of a text. However, many people have obstacles in reading. This paper summarizes the main barriers in reading fast and puts forward some strategies for improving reading speed.

  19. Obstacle Avoidance of a Mobile Robot with Hierarchical Structure

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chan Gyu [Yeungnam College of Science and Technolgy, Taegu (Korea)

    2001-06-01

    This paper proposed a new hierarchical fuzzy-neural network algorithm for navigation of a mobile robot within unknown dynamic environment. Proposed navigation algorithm used the learning ability of the neural network and the feasibility of control highly nonlinear system of fuzzy theory. The proposed navigation algorithm used fuzzy algorithm for goal approach and fuzzy-network for effective collision avoidance. Some computer simulation results for a mobile robot equipped with ultrasonic range sensors show that the suggested navigation algorithm is very effective to escape in stationary and moving obstacles environment. (author). 11 refs., 14 figs., 2 tabs.

  20. Informal face-to-face interaction improves mood state reflected in prefrontal cortex activity

    Directory of Open Access Journals (Sweden)

    Jun-Ichiro eWatanabe

    2016-05-01

    Full Text Available Recent progress with wearable sensors has enabled researchers to capture face-to-face interactions quantitatively and given great insight into human dynamics. One attractive field for applying such sensors is the workplace, where the relationship between the face-to-face behaviors of employees and the productivity of the organization has been investigated. One interesting result of previous studies showed that informal face-to-face interaction among employees, captured by wearable sensors that the employees wore, significantly affects their performance. However, the mechanism behind this relationship has not yet been adequately explained, though experiences at the job scene might qualitatively support the finding. We hypothesized that informal face-to-face interaction improves mood state, which in turn affects the task performance. To test this hypothesis, we evaluated the change of mood state before and after break time for two groups of participants, one that spent their breaks alone and one that spent them with other participants, by administering questionnaires and taking brain activity measurements. Recent neuroimaging studies have suggested a significant relationship between mood state and brain activity. Here, we show that face-to-face interaction during breaks significantly improved mood state, which was measured by Profiles of Mood States (POMS.We also observed that the verbal WM task performance of participants who did not have face-to-face interaction during breaks decreased significantly. In this paper, we discuss how the change of mood state was evidenced in the prefrontal cortex (PFC activity accompanied by working memory (WM tasks measured by near-infrared spectroscopy (NIRS.

  1. Informal Face-to-Face Interaction Improves Mood State Reflected in Prefrontal Cortex Activity

    Science.gov (United States)

    Watanabe, Jun-ichiro; Atsumori, Hirokazu; Kiguchi, Masashi

    2016-01-01

    Recent progress with wearable sensors has enabled researchers to capture face-to-face interactions quantitatively and given great insight into human dynamics. One attractive field for applying such sensors is the workplace, where the relationship between the face-to-face behaviors of employees and the productivity of the organization has been investigated. One interesting result of previous studies showed that informal face-to-face interaction among employees, captured by wearable sensors that the employees wore, significantly affects their performance. However, the mechanism behind this relationship has not yet been adequately explained, though experiences at the job scene might qualitatively support the finding. We hypothesized that informal face-to-face interaction improves mood state, which in turn affects the task performance. To test this hypothesis, we evaluated the change of mood state before and after break time for two groups of participants, one that spent their breaks alone and one that spent them with other participants, by administering questionnaires and taking brain activity measurements. Recent neuroimaging studies have suggested a significant relationship between mood state and brain activity. Here, we show that face-to-face interaction during breaks significantly improved mood state, which was measured by Profiles of Mood States (POMS). We also observed that the verbal working memory (WM) task performance of participants who did not have face-to-face interaction during breaks decreased significantly. In this paper, we discuss how the change of mood state was evidenced in the prefrontal cortex (PFC) activity accompanied by WM tasks measured by near-infrared spectroscopy (NIRS). PMID:27199715

  2. Elimination of a spiral wave pinned at an obstacle by a train of plane waves: Effect of diffusion between obstacles and surrounding media

    Science.gov (United States)

    Tanaka, Masanobu; Hörning, Marcel; Kitahata, Hiroyuki; Yoshikawa, Kenichi

    2015-10-01

    In excitable media such as cardiac tissue and Belousov-Zhabotinsky reaction medium, spiral waves tend to anchor (pin) to local heterogeneities. In general, such pinned waves are difficult to eliminate and may progress to spatio-temporal chaos. Heterogeneities can be classified as either the absence or presence of diffusive interaction with the surrounding medium. In this study, we investigated the difference in the unpinning of spiral waves from obstacles with and without diffusive interaction, and found a profound difference. The pacing period required for unpinning at fixed obstacle size is larger in case of diffusive obstacles. Further, we deduced a generic theoretical framework that can predict the minimal unpinning period. Our results explain the difference in pacing periods between for the obstacles with and without diffusive interaction, and the difference is interpreted in terms of the local decrease of spiral wave velocity close to the obstacle boundary caused in the case of diffusive interaction.

  3. Elimination of a spiral wave pinned at an obstacle by a train of plane waves: Effect of diffusion between obstacles and surrounding media

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Masanobu [Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502 (Japan); Hörning, Marcel [Institute for Integrated Cell-Material Sciences, Kyoto University, Kyoto 606-8501 (Japan); Kitahata, Hiroyuki, E-mail: kitahata@chiba-u.jp [Department of Physics, Graduate School of Science, Chiba University, Chiba 263-8522 (Japan); Yoshikawa, Kenichi [Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Kyoto 610-0394 (Japan)

    2015-10-15

    In excitable media such as cardiac tissue and Belousov-Zhabotinsky reaction medium, spiral waves tend to anchor (pin) to local heterogeneities. In general, such pinned waves are difficult to eliminate and may progress to spatio-temporal chaos. Heterogeneities can be classified as either the absence or presence of diffusive interaction with the surrounding medium. In this study, we investigated the difference in the unpinning of spiral waves from obstacles with and without diffusive interaction, and found a profound difference. The pacing period required for unpinning at fixed obstacle size is larger in case of diffusive obstacles. Further, we deduced a generic theoretical framework that can predict the minimal unpinning period. Our results explain the difference in pacing periods between for the obstacles with and without diffusive interaction, and the difference is interpreted in terms of the local decrease of spiral wave velocity close to the obstacle boundary caused in the case of diffusive interaction.

  4. Image Pixel Fusion for Human Face Recognition

    CERN Document Server

    Bhowmik, Mrinal Kanti; Nasipuri, Mita; Basu, Dipak Kumar; Kundu, Mahantapas

    2010-01-01

    In this paper we present a technique for fusion of optical and thermal face images based on image pixel fusion approach. Out of several factors, which affect face recognition performance in case of visual images, illumination changes are a significant factor that needs to be addressed. Thermal images are better in handling illumination conditions but not very consistent in capturing texture details of the faces. Other factors like sunglasses, beard, moustache etc also play active role in adding complicacies to the recognition process. Fusion of thermal and visual images is a solution to overcome the drawbacks present in the individual thermal and visual face images. Here fused images are projected into an eigenspace and the projected images are classified using a radial basis function (RBF) neural network and also by a multi-layer perceptron (MLP). In the experiments Object Tracking and Classification Beyond Visible Spectrum (OTCBVS) database benchmark for thermal and visual face images have been used. Compar...

  5. Face recognition with L1-norm subspaces

    Science.gov (United States)

    Maritato, Federica; Liu, Ying; Colonnese, Stefania; Pados, Dimitris A.

    2016-05-01

    We consider the problem of representing individual faces by maximum L1-norm projection subspaces calculated from available face-image ensembles. In contrast to conventional L2-norm subspaces, L1-norm subspaces are seen to offer significant robustness to image variations, disturbances, and rank selection. Face recognition becomes then the problem of associating a new unknown face image to the "closest," in some sense, L1 subspace in the database. In this work, we also introduce the concept of adaptively allocating the available number of principal components to different face image classes, subject to a given total number/budget of principal components. Experimental studies included in this paper illustrate and support the theoretical developments.

  6. Orienting to face expression during encoding improves men's recognition of own gender faces.

    Science.gov (United States)

    Fulton, Erika K; Bulluck, Megan; Hertzog, Christopher

    2015-10-01

    It is unclear why women have superior episodic memory of faces, but the benefit may be partially the result of women engaging in superior processing of facial expressions. Therefore, we hypothesized that orienting instructions to attend to facial expression at encoding would significantly improve men's memory of faces and possibly reduce gender differences. We directed 203 college students (122 women) to study 120 faces under instructions to orient to either the person's gender or their emotional expression. They later took a recognition test of these faces by either judging whether they had previously studied the same person or that person with the exact same expression; the latter test evaluated recollection of specific facial details. Orienting to facial expressions during encoding significantly improved men's recognition of own-gender faces and eliminated the advantage that women had for male faces under gender orienting instructions. Although gender differences in spontaneous strategy use when orienting to faces cannot fully account for gender differences in face recognition, orienting men to facial expression during encoding is one way to significantly improve their episodic memory for male faces.

  7. Interaction of a highly radiative shock with a solid obstacle

    Science.gov (United States)

    Koenig, M.; Michel, Th.; Yurchak, R.; Michaut, C.; Albertazzi, B.; Laffite, S.; Falize, E.; Van Box Som, L.; Sakawa, Y.; Sano, T.; Hara, Y.; Morita, T.; Kuramitsu, Y.; Barroso, P.; Pelka, A.; Gregori, G.; Kodama, R.; Ozaki, N.; Lamb, D.; Tzeferacos, P.

    2017-08-01

    In this paper, we present the recent results obtained regarding highly radiative shocks (RSs) generated in a low-density gas filled cell on the GEKKO XII laser facility. The RS was generated by using an ablator-pusher two-layer target (CH/Sn) and a propagation medium (Xe). High velocity RSs have been generated (100-140 km/s), while limiting as much as possible the preheating produced by the corona emission. Both self-emission and visible probe diagnostics highlighted a strong emission in the shock and an electron density in the downstream gas. The RS characteristics that depend on the initial conditions are described here as well as its precursor interaction with an aluminium foil used as an obstacle. The obtained results are discussed which show a strong extension of the radiative precursor (1 mm) leading to an expansion velocity of the obstacle up to ≈30 km/s compatible to a 20 eV temperature.

  8. Trust-based learning and behaviors for convoy obstacle avoidance

    Science.gov (United States)

    Mikulski, Dariusz G.; Karlsen, Robert E.

    2015-05-01

    In many multi-agent systems, robots within the same team are regarded as being fully trustworthy for cooperative tasks. However, the assumption of trustworthiness is not always justified, which may not only increase the risk of mission failure, but also endanger the lives of friendly forces. In prior work, we addressed this issue by using RoboTrust to dynamically adjust to observed behaviors or recommendations in order to mitigate the risks of illegitimate behaviors. However, in the simulations in prior work, all members of the convoy had knowledge of the convoy goal. In this paper, only the lead vehicle has knowledge of the convoy goals and the follow vehicles must infer trustworthiness strictly from lead vehicle performance. In addition, RoboTrust could only respond to observed performance and did not dynamically learn agent behavior. In this paper, we incorporate an adaptive agent-specific bias into the RoboTrust algorithm that modifies its trust dynamics. This bias is learned incrementally from agent interactions, allowing good agents to benefit from faster trust growth and slower trust decay and bad agents to be penalized with slower trust growth and faster trust decay. We then integrate this new trust model into a trust-based controller for decentralized autonomous convoy operations. We evaluate its performance in an obstacle avoidance mission, where the convoy attempts to learn the best speed and following distances combinations for an acceptable obstacle avoidance probability.

  9. Random walk of passive tracers among randomly moving obstacles

    CERN Document Server

    Gori, Matteo; Floriani, Elena; Nardecchia, Ilaria; Pettini, Marco

    2016-01-01

    Background: This study is mainly motivated by the need of understanding how the diffusion behaviour of a biomolecule (or even of a larger object) is affected by other moving macromolecules, organelles, and so on, inside a living cell, whence the possibility of understanding whether or not a randomly walking biomolecule is also subject to a long-range force field driving it to its target. Method: By means of the Continuous Time Random Walk (CTRW) technique the topic of random walk in random environment is here considered in the case of a passively diffusing particle in a crowded environment made of randomly moving and interacting obstacles. Results: The relevant physical quantity which is worked out is the diffusion cofficient of the passive tracer which is computed as a function of the average inter-obstacles distance. Coclusions: The results reported here suggest that if a biomolecule, let us call it a test molecule, moves towards its target in the presence of other independently interacting molecules, its m...

  10. Ladar System Identifies Obstacles Partly Hidden by Grass

    Science.gov (United States)

    Castano, Andres

    2003-01-01

    A ladar-based system now undergoing development is intended to enable an autonomous mobile robot in an outdoor environment to avoid moving toward trees, large rocks, and other obstacles that are partly hidden by tall grass. The design of the system incorporates the assumption that the robot is capable of moving through grass and provides for discrimination between grass and obstacles on the basis of geometric properties extracted from ladar readings as described below. The system (see figure) includes a ladar system that projects a range-measuring pulsed laser beam that has a small angular width of radians and is capable of measuring distances of reflective objects from a minimum of dmin to a maximum of dmax. The system is equipped with a rotating mirror that scans the beam through a relatively wide angular range of in a horizontal plane at a suitable small height above the ground. Successive scans are performed at time intervals of seconds. During each scan, the laser beam is fired at relatively small angular intervals of radians to make range measurements, so that the total number of range measurements acquired in a scan is Ne = / .

  11. Humans perceive object motion in world coordinates during obstacle avoidance.

    Science.gov (United States)

    Fajen, Brett R; Parade, Melissa S; Matthis, Jonathan S

    2013-07-25

    A fundamental question about locomotion in the presence of moving objects is whether movements are guided based upon perceived object motion in an observer-centered or world-centered reference frame. The former captures object motion relative to the moving observer and depends on both observer and object motion. The latter captures object motion relative to the stationary environment and is independent of observer motion. Subjects walked through a virtual environment (VE) viewed through a head-mounted display and indicated whether they would pass in front of or behind a moving obstacle that was on course to cross their future path. Subjects' movement through the VE was manipulated such that object motion in observer coordinates was affected while object motion in world coordinates was the same. We found that when moving observers choose routes around moving obstacles, they rely on object motion perceived in world coordinates. This entails a process, which has been called flow parsing (Rushton & Warren, 2005; Warren & Rushton, 2009a), that recovers the component of optic flow due to object motion independent of self-motion. We found that when self-motion is real and actively generated, the process by which object motion is recovered relies on both visual and nonvisual information to factor out the influence of self-motion. The remaining component contains information about object motion in world coordinates that is needed to guide locomotion.

  12. Academic programs, class sizes, and obstacles to growth in audiology.

    Science.gov (United States)

    Windmill, Ian M

    2013-05-01

    Over the past 25 yr, the number of academic programs in audiology has been cut by half, yet there continue to be calls for further reductions in the number of programs. Reducing the number of programs potentially affects the number of graduates and therefore could impact the availability of audiologists in the future. There is a question as to whether academic programs in audiology could accommodate more students. To examine the impact of closure of programs on the number of graduates and to identify obstacles to programs growing class sizes. An analysis of audiology class sizes over time based on data available from the Council of Academic Programs in Communication Sciences and Disorders, and a comparison of audiology class sizes with other health professions, to identify trends that affect growth in program size. The key obstacles to growth of academic programs are (1) the availability of sufficient clinical experiences to meet the licensure and certification requirements and (2) financial resources to expand didactic and clinical teaching needs associated with larger class sizes. (1) Certification regulations and licensure laws should be revised to eliminate requirements that directly impact on academic programs or students prior to graduation. (2) The profession should undertake the effort designed to change Medicare regulations to allow alternative supervision models. (3) Academic programs need freedom to be creative in their approaches to teaching and financing programs. (4) A concerted and coordinated effort needs to be undertaken to increase the number of persons interested in audiology as a career. American Academy of Audiology.

  13. Vitalism as an Epistemological Obstacle to Biochemical Knowledge

    Directory of Open Access Journals (Sweden)

    R.V. Almeida

    2010-05-01

    Full Text Available This work resulted from the study of Gaston Bachelard’s epistemology in the Logic and Philosophy of Science discipline, Biochemistry Graduate Program, UFRJ, which lead to discussions of epistemological obstacles on biochemical knowledge construction. The aim was to identify barriers to scientific knowledge development in the praxis of graduate students of biochemistry and correlated areas, emphasizing the vitalist (animist and teleological (unitary and pragmatic obstacles conceptions. In order to verify whether students, which never attended classes in epistemology, agree or are able to identify the vitalist conception, a questionnaire containing also selected excerpts of scientific papers in high impact factor journals was delivered to thirty graduating students from different courses at UFRJ and other Brazilian universities. Not only those conceptions were accepted or were not recognized, but it was also possible to observe a vitalist approach in the answers. We could also perceive a pragmatic and teleological vision of the evolution process, expressed in apologies of immanent purposes in organisms adaptations. Considering these facts, it is clear the necessity to emphasize the material, non-teleological character of biochemistry/biology, especially in disciplines offered in under-graduate courses.

  14. Facing Sound - Voicing Art

    DEFF Research Database (Denmark)

    Lønstrup, Ansa

    2013-01-01

    This article is based on examples of contemporary audiovisual art, with a special focus on the Tony Oursler exhibition Face to Face at Aarhus Art Museum ARoS in Denmark in March-July 2012. My investigation involves a combination of qualitative interviews with visitors, observations of the audienc......´s interactions with the exhibition and the artwork in the museum space and short analyses of individual works of art based on reception aesthetics and phenomenology and inspired by newer writings on sound, voice and listening....

  15. Low dimensional representation of face space by face-selective inferior temporal neurons.

    Science.gov (United States)

    Salehi, Sina; Dehaqani, Mohammad-Reza A; Esteky, Hossein

    2017-05-01

    The representation of visual objects in primate brain is distributed and multiple neurons are involved in encoding each object. One way to understand the neural basis of object representation is to estimate the number of neural dimensions that are needed for veridical representation of object categories. In this study, the characteristics of the match between physical-shape and neural representational spaces in monkey inferior temporal (IT) cortex were evaluated. Specifically, we examined how the number of neural dimensions, stimulus behavioral saliency and stimulus category selectivity of neurons affected the correlation between shape and neural representational spaces in IT cortex. Single-unit recordings from monkey IT cortex revealed that there was a significant match between face space and its neural representation at lower neural dimensions, whereas the optimal match for the non-face objects was observed at higher neural dimensions. There was a statistically significant match between the face and neural spaces only in the face-selective neurons, whereas a significant match was observed for non-face objects in all neurons regardless of their category selectivity. Interestingly, the face neurons showed a higher match for the non-face objects than for the faces at higher neural dimensions. The optimal representation of face space in the responses of the face neurons was a low dimensional map that emerged early (~150 ms post-stimulus onset) and was followed by a high dimensional and relatively late (~300 ms) map for the non-face stimuli. These results support a multiplexing function for the face neurons in the representation of very similar shape spaces, but with different dimensionality and timing scales. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  16. Avoiding moving obstacles by deviation from a mobile robot`s nominal path

    Energy Technology Data Exchange (ETDEWEB)

    Tsoularis, A.; Kambhampati, C. [Univ. of Reading, Whiteknights (United Kingdom). Dept. of Cybernetics

    1999-05-01

    This paper deals with the problem of obstacle avoidance by deviation from the nominal path. Deviation is the only option available to the robot when the acceleration or deceleration plan on the nominal path fails to produce a viable avoidance strategy. The obstacle avoidance on the nominal path was dealt with in the authors` previous development, where the robot`s motion was only subject to an upper bound on its speed. When the robot has to deviate, its motion is subject to a maximum steering constraint and a maximum deviation constraint in addition to the maximum speed constraint. The problem is solved geometrically by identifying final states for the robot that are reachable, satisfy all the constraints, and guarantee collision avoidance. The final state-reachability conditions that the authors obtain in the process ensure that no unnecessary deviation plan is initiated. These conditions, along with the simplicity of the geometric arguments they employ, make the scheme an attractive option for on-line implementation. The only significant complexity arises when minimizing the performance index. They have suggested dynamic programming as an optimization took, but any other nonlinear optimization technique can be adopted.

  17. Stochastic Differential Games with Reflection and Related Obstacle Problems for Isaacs Equations

    Institute of Scientific and Technical Information of China (English)

    Rainer BUCKDAHN; Juan LI

    2011-01-01

    In this paper we first investigate zero-sum two-player stochastic differential games with reflection,with the help of theory of Reflected Backward Stochastic Differential Equations (RBSDEs).We will establish the dynamic programming principle for the upper and the lower value functions of this kind of stochastic differential games with reflection in a straightforward way.Then the upper and the lower value functions are proved to be the unique viscosity solutions to the associated upper and the lower Hamilton-Jacobi-Bellman-Isaacs equations with obstacles,respectively.The method differs significantly from those used for control problems with reflection,with new techniques developed of interest on its own.Further,we also prove a new estimate for RBSDEs being sharper than that in the paper of El Karoui,Kapoudjian,Pardoux,Peng and Quenez (1997),which turns out to be very useful because it allows us to estimate the Lp-distance of the solutions of two different RBSDEs by the p-th power of the distance of the initial values of the driving forward equations.We also show that the unique viscosity solution to the approximating Isaacs equation constructed by the penalization method converges to the viscosity solution of the Isaacs equation with obstacle.

  18. Sensor-based whole-arm obstacle avoidance utilizing ASIC technology

    Science.gov (United States)

    Wintenberg, A. L.; Ericson, M. N.; Babcock, S. M.; Armstrong, G. A.; Britton, C. L., Jr.; Butler, P. L.; Hamel, W. R.; Newport, D. F.

    Operation of manipulator systems in poorly defined work environments often presents a significant hazard to both the robotic assembly and the environment. In applications relating to the Environmental Restoration and Waste Management (ER&WM) Program, many of the environments are considered hazardous, both, in the structure and composition of the environment. Use of a sensing system that provides information to the manipulator control unit regarding obstacles in close proximity will provide protection against collisions. A hierarchical design and implementation of a whole-arm obstacle avoidance system is presented. The system is based on capacitive sensors configured as bracelets for proximity sensing. Each bracelet contains a number of sensor nodes and a processor for sensor node control and readout, and communications with a higher level host, common to all bracelets. The host controls the entire sensing network and communicates proximity information to the manipulator controller. The overall architecture of this system is discussed with detail on the individual system modules. Details of an application specific integrated circuit (ASIC) designed to implement the sensor node electronics are presented. Justifications for the general measurement methods and associated implementation are discussed. Additionally, the current state of development including measured data is presented.

  19. Effects of unconscious processing on implicit memory for fearful faces.

    Directory of Open Access Journals (Sweden)

    Jiongjiong Yang

    Full Text Available Emotional stimuli can be processed even when participants perceive them without conscious awareness, but the extent to which unconsciously processed emotional stimuli influence implicit memory after short and long delays is not fully understood. We addressed this issue by measuring a subliminal affective priming effect in Experiment 1 and a long-term priming effect in Experiment 2. In Experiment 1, a flashed fearful or neutral face masked by a scrambled face was presented three times, then a target face (either fearful or neutral was presented and participants were asked to make a fearful/neutral judgment. We found that, relative to a neutral prime face (neutral-fear face, a fearful prime face speeded up participants' reaction to a fearful target (fear-fear face, when they were not aware of the masked prime face. But this response pattern did not apply to the neutral target. In Experiment 2, participants were first presented with a masked faces six times during encoding. Three minutes later, they were asked to make a fearful/neutral judgment for the same face with congruent expression, the same face with incongruent expression or a new face. Participants showed a significant priming effect for the fearful faces but not for the neutral faces, regardless of their awareness of the masked faces during encoding. These results provided evidence that unconsciously processed stimuli could enhance emotional memory after both short and long delays. It indicates that emotion can enhance memory processing whether the stimuli are encoded consciously or unconsciously.

  20. Conjunction Faces Alter Confidence-Accuracy Relations for Old Faces

    Science.gov (United States)

    Reinitz, Mark Tippens; Loftus, Geoffrey R.

    2017-01-01

    The authors used a state-trace methodology to investigate the informational dimensions used to recognize old and conjunction faces (made by combining parts of separately studied faces). Participants in 3 experiments saw faces presented for 1 s each. They then received a recognition test; faces were presented for varying brief durations and…

  1. Pedagogical Characteristics of Online and Face-to-Face Classes

    Science.gov (United States)

    Wuensch, Karl; Aziz, Shahnaz; Ozan, Erol; Kishore, Masao; Tabrizi, M. H. Nassehzadeh

    2008-01-01

    Currently, many students have had experience with both face-to-face and online classes. We asked such students at 46 different universities in the United States to evaluate the pedagogical characteristics of their most recently completed face-to-face class and their most recently completed online class. The results show that students rate online…

  2. Bayesian Face Recognition and Perceptual Narrowing in Face-Space

    Science.gov (United States)

    Balas, Benjamin

    2012-01-01

    During the first year of life, infants' face recognition abilities are subject to "perceptual narrowing", the end result of which is that observers lose the ability to distinguish previously discriminable faces (e.g. other-race faces) from one another. Perceptual narrowing has been reported for faces of different species and different races, in…

  3. Real Time Face Quality Assessment for Face Log Generation

    DEFF Research Database (Denmark)

    Kamal, Nasrollahi; Moeslund, Thomas B.

    2009-01-01

    Summarizing a long surveillance video to just a few best quality face images of each subject, a face-log, is of great importance in surveillance systems. Face quality assessment is the back-bone for face log generation and improving the quality assessment makes the face logs more reliable....... Developing a real time face quality assessment system using the most important facial features and employing it for face logs generation are the concerns of this paper. Extensive tests using four databases are carried out to validate the usability of the system....

  4. Comparison of Face-to-Face and Web Surveys on the Topic of Homosexual Rights.

    Science.gov (United States)

    Liu, Mingnan; Wang, Yichen

    2016-06-01

    Although academic research on homosexuality relies heavily on survey data, there has been limited study of the survey method of asking relevant questions. This study examines the effect of survey mode on responses to questions about homosexual rights. We find significant mode effects among heterosexual respondents, who are more likely to support equal access to employment, military service, adoption, and marriage for homosexual people in face-to-face surveys than in Web surveys. They are also more likely to choose to not respond when face-to-face than online. Homosexual respondents do not show mode effects for either substantive responses or item nonresponse rate.

  5. Exploring the spatio-temporal neural basis of face learning.

    Science.gov (United States)

    Yang, Ying; Xu, Yang; Jew, Carol A; Pyles, John A; Kass, Robert E; Tarr, Michael J

    2017-06-01

    Humans are experts at face individuation. Although previous work has identified a network of face-sensitive regions and some of the temporal signatures of face processing, as yet, we do not have a clear understanding of how such face-sensitive regions support learning at different time points. To study the joint spatio-temporal neural basis of face learning, we trained subjects to categorize two groups of novel faces and recorded their neural responses using magnetoencephalography (MEG) throughout learning. A regression analysis of neural responses in face-sensitive regions against behavioral learning curves revealed significant correlations with learning in the majority of the face-sensitive regions in the face network, mostly between 150-250 ms, but also after 300 ms. However, the effect was smaller in nonventral regions (within the superior temporal areas and prefrontal cortex) than that in the ventral regions (within the inferior occipital gyri (IOG), midfusiform gyri (mFUS) and anterior temporal lobes). A multivariate discriminant analysis also revealed that IOG and mFUS, which showed strong correlation effects with learning, exhibited significant discriminability between the two face categories at different time points both between 150-250 ms and after 300 ms. In contrast, the nonventral face-sensitive regions, where correlation effects with learning were smaller, did exhibit some significant discriminability, but mainly after 300 ms. In sum, our findings indicate that early and recurring temporal components arising from ventral face-sensitive regions are critically involved in learning new faces.

  6. Face recognition system and method using face pattern words and face pattern bytes

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Yufeng

    2014-12-23

    The present invention provides a novel system and method for identifying individuals and for face recognition utilizing facial features for face identification. The system and method of the invention comprise creating facial features or face patterns called face pattern words and face pattern bytes for face identification. The invention also provides for pattern recognitions for identification other than face recognition. The invention further provides a means for identifying individuals based on visible and/or thermal images of those individuals by utilizing computer software implemented by instructions on a computer or computer system and a computer readable medium containing instructions on a computer system for face recognition and identification.

  7. Multibiometrics for face recognition

    NARCIS (Netherlands)

    Veldhuis, Raymond; Deravi, Farzin; Tao, Qian

    2008-01-01

    Fusion is a popular practice to combine multiple sources of biometric information to achieve systems with greater performance and flexibility. In this paper various approaches to fusion within a multibiometrics context are considered and an application to the fusion of 2D and 3D face information is

  8. Multibiometrics for face recognition

    NARCIS (Netherlands)

    Veldhuis, Raymond N.J.; Deravi, Farzin; Tao, Q.

    Fusion is a popular practice to combine multiple sources of biometric information to achieve systems with greater performance and flexibility. In this paper various approaches to fusion within a multibiometrics context are considered and an application to the fusion of 2D and 3D face information is

  9. Two Faces of Japan.

    Science.gov (United States)

    Beasley, Conger, Jr.

    1992-01-01

    Discusses the inconsistency between Japanese exploitation of world natural resources and gestures to provide leadership in ecologically innovative technology. Explores Japanese culture, power structure, population trends, environmental ethics, industrialism, and international business practices as they relate to the philosophical face of…

  10. Bayesian Face Sketch Synthesis.

    Science.gov (United States)

    Wang, Nannan; Gao, Xinbo; Sun, Leiyu; Li, Jie

    2017-03-01

    Exemplar-based face sketch synthesis has been widely applied to both digital entertainment and law enforcement. In this paper, we propose a Bayesian framework for face sketch synthesis, which provides a systematic interpretation for understanding the common properties and intrinsic difference in different methods from the perspective of probabilistic graphical models. The proposed Bayesian framework consists of two parts: the neighbor selection model and the weight computation model. Within the proposed framework, we further propose a Bayesian face sketch synthesis method. The essential rationale behind the proposed Bayesian method is that we take the spatial neighboring constraint between adjacent image patches into consideration for both aforementioned models, while the state-of-the-art methods neglect the constraint either in the neighbor selection model or in the weight computation model. Extensive experiments on the Chinese University of Hong Kong face sketch database demonstrate that the proposed Bayesian method could achieve superior performance compared with the state-of-the-art methods in terms of both subjective perceptions and objective evaluations.

  11. Facing Up to Death

    Science.gov (United States)

    Ross, Elizabeth Kubler

    1972-01-01

    Doctor urges that Americans accept death as a part of life and suggests ways of helping dying patients and their families face reality calmly, with peace. Dying children and their siblings, as well as children's feelings about relatives' deaths, are also discussed. (PD)

  12. Autonomous Face Segmentation

    Science.gov (United States)

    1992-09-01

    and Rhea Diamond. "From Piecemeal to Configurational Repre- sentation of Faces," Science, 195:312-314 (Jan 1977). 3. Damasio , Antonio R...34Prosopagnosia," Trends in Neuroscience, 8:132-135 (1985). 4. Damasio , Antonio R. and others. "Prosopagnosia: Anatomic Basis and Behav- ioral Mechanisms

  13. PrimeFaces blueprints

    CERN Document Server

    Jonna, Sudheer

    2014-01-01

    If you are a Java developer with experience of frontend UI development, and want to take the plunge to develop stunning UI applications with the most popular JSF framework, PrimeFaces, then this book is for you. For those with entrepreneurial aspirations, this book will provide valuable insights into how to utilize successful business models.

  14. Facing Up to Death

    Science.gov (United States)

    Ross, Elizabeth Kubler

    1972-01-01

    Doctor urges that Americans accept death as a part of life and suggests ways of helping dying patients and their families face reality calmly, with peace. Dying children and their siblings, as well as children's feelings about relatives' deaths, are also discussed. (PD)

  15. The university student experience of face-to-face and online discussions: coherence, reflection and meaning

    Directory of Open Access Journals (Sweden)

    Robert A. Ellis

    2007-12-01

    Full Text Available This paper reports on an investigation into learning through discussions by undergraduate social work students. Second-year students studying psychology for social work experienced discussions began with face-to-face tutorials, and then continued for some time after online. This study used closed-ended questionnaires to investigate what students thought they were learning through discussions (their concepts, and how they engaged in the discussions face-to-face and online (their approaches. Significant associations were found among students' concepts of discussions, approaches and levels of achievement. The results suggest that students who do not understand how discussions can help them to interrogate, reflect on and revise their ideas tended not to approach either face-to-face or online discussions in ways likely to improve their understanding or their levels of achievement. This type of insight is critical for teacher/designers wishing to create university experiences in which discussion is used to promote learning.

  16. An exploration into pedagogic frailty: Transitioning from face-to-face to online

    Directory of Open Access Journals (Sweden)

    Irina Niculescu

    2017-09-01

    Full Text Available Pedagogic frailty and concept mapping can simultaneously encourage personal and organisational change by supporting critical reflection and resilience. These ideas are nascent within higher education institutions and currently, at the University of Surrey, are only developed through face-to-face sessions. This revealed the need for a scalable intervention which engages academics with the discourse on introspective and professional development practices. In response, we have created the design for a blended programme of online foundation for concept mapping leading to face-to-face workshops to explore the pedagogic frailty model. This paper will discuss some significant challenges arising from transitioning self-reflective practices from face-to-face to online spaces. In the process, we will consider ways in which learning design can take the learner context into account.

  17. Type of Instructional Delivery and Second Language Teacher Candidate Performance: Online versus Face-to-Face

    Science.gov (United States)

    Kissau, Scott

    2015-01-01

    Research conducted over the past decade has consistently reported no significant differences in learning outcomes for students of fully online or face-to-face (F2F) instruction. Only a small number of these studies, however, have focused on courses in second language (L2) teacher preparation programs. Even fewer studies have compared the impact of…

  18. Face recognition performance of individuals with Asperger syndrome on the Cambridge Face Memory Test.

    Science.gov (United States)

    Hedley, Darren; Brewer, Neil; Young, Robyn

    2011-12-01

    Although face recognition deficits in individuals with Autism Spectrum Disorder (ASD), including Asperger syndrome (AS), are widely acknowledged, the empirical evidence is mixed. This in part reflects the failure to use standardized and psychometrically sound tests. We contrasted standardized face recognition scores on the Cambridge Face Memory Test (CFMT) for 34 individuals with AS with those for 42, IQ-matched non-ASD individuals, and age-standardized scores from a large Australian cohort. We also examined the influence of IQ, autistic traits, and negative affect on face recognition performance. Overall, participants with AS performed significantly worse on the CFMT than the non-ASD participants and when evaluated against standardized test norms. However, while 24% of participants with AS presented with severe face recognition impairment (>2 SDs below the mean), many individuals performed at or above the typical level for their age: 53% scored within +/- 1 SD of the mean and 9% demonstrated superior performance (>1 SD above the mean). Regression analysis provided no evidence that IQ, autistic traits, or negative affect significantly influenced face recognition: diagnostic group membership was the only significant predictor of face recognition performance. In sum, face recognition performance in ASD is on a continuum, but with average levels significantly below non-ASD levels of performance.

  19. Age-Dependent Face Detection and Face Categorization Performance

    OpenAIRE

    Claus-Christian Carbon; Martina Grüter; Thomas Grüter

    2013-01-01

    Empirical studies on the development of face processing skills with age show inconsistent patterns concerning qualitative vs. quantitative changes over time or the age range for peak cognitive performance. In the present study, we tested the proficiency in face detection and face categorization with a large sample of participants (N = 312; age range: 2-88 yrs). As test objects, we used so-called Mooney faces, two-tone (black and white) images of faces lacking critical information of a local, ...

  20. Maîtriser la demande d'énergie, une option consensuelle face à ses obstacles

    OpenAIRE

    Ha-Duong, Minh; Finon, Dominique

    2014-01-01

    226; Le CIRED a organisé un colloque le jeudi 20 mars 2014 à l'auditorium du CNRS. Cet événement a été produit dans le cadre du projet de recherche européen R&Dialogue, en association avec le laboratoire PACTE (U. Grenoble-CNRS) et avec le soutien de l'INSHS et de l'INSIS du CNRS. Ce document constitue les actes de cette journée. Son sommaire reprend le déroulé des exposés. Il est organisé en cinq parties correspondant aux sessions : * A. " L'efficacité des consommations dans le bâtiment : en...

  1. Obstacle detection contribution for automotive applications; Contribution a la detection d'obstacles pour la voiture intelligente

    Energy Technology Data Exchange (ETDEWEB)

    Wahl, M.

    1997-12-05

    On the one hand, this Ph-D Thesis deals with a new architectural approach for automotive applications implementing heterogeneous sensor data fusion, and on the other hand, it explains the data pre-processing algorithm of a microwave radar. Firstly, the analysis of both PROCHIP2 and PROLAB2 obstacle detection demonstrators (cf. the European PROMETHEUS research program about smart cars) has led us to propose a new functional architecture. Our approach introduces a sensor data pre-processing level. Data are then running at the local sensor before being transferred to data fusion architectures (that classically receives data whose meaning has also been noised by the application distribution). Secondly, an elementary simulator has been designed in order to complement our database composed of experimental microwave radar data. It is able to generate radar data for basic highway traffic scenarios. With both experimental and simulated data, a deterministic radar data pre-processing algorithm has been designed. It reduces the amount of data to be transferred by converting the local radar data into a higher semantic information: it gives more pertinent data (for example: velocities...) to the data fusion level; in particular, it predicts the obstacle path. Finally, some perspectives have been set out. Firstly, an H {infinity} estimation approach is used to reduce the data disruption effect that alters the radar data and, secondly, a controller has been proposed with the goal of decreasing the effect of car pitching. (author)

  2. Old Disease and New Challenges: Major Obstacles of Current Strategies in the Prevention of Pertussis

    Directory of Open Access Journals (Sweden)

    Iraj Sedighi

    2016-06-01

    Full Text Available Context Universal immunization against Bordetella pertussis has partially controlled the burden of the disease and its transmission. However, according to recent data, the epidemiology of this vaccine-preventable disease has changed. Now, younger infants, adolescents, and adults are at greater risk of infection. This article has studied the interaction between the various factors involved in the changing epidemiology of pertussis and the major obstacles faced by the current strategies in its prevention. Evidence Acquisition In this narrative review, the most recently published sources of information on pertussis control measures, consisting of textbooks and articles, have been reviewed. We focused on the more recent data about the changing epidemiology or pertussis in Scopus through the use of the MeSH-term words [pertussis] or [whooping cough] and [epidemiology] or [outbreak] or [resurgence], but our search was not restricted to this particular strategy; we also tried to find all of the most recent available data in the general field through other means. Results Primary and booster doses of the pertussis vaccine seem to partially control transmission of the disease, but despite the different preventive strategies available, pertussis continues to cause mortality and morbidity among high-risk groups. Conclusions Adding booster doses of acellular pertussis vaccine to the current national immunization practices with whole-cell vaccines for young adults and pregnant women seems to be a good option for controlling mortality and morbidity among high-risk groups such as very young infants.

  3. Old Disease and New Challenges: Major Obstacles of Current Strategies in the Prevention of Pertussis

    Science.gov (United States)

    Sedighi, Iraj; Karimi, Abdollah; Amanati, Ali

    2016-01-01

    Context Universal immunization against Bordetella pertussis has partially controlled the burden of the disease and its transmission. However, according to recent data, the epidemiology of this vaccine-preventable disease has changed. Now, younger infants, adolescents, and adults are at greater risk of infection. This article has studied the interaction between the various factors involved in the changing epidemiology of pertussis and the major obstacles faced by the current strategies in its prevention. Evidence Acquisition In this narrative review, the most recently published sources of information on pertussis control measures, consisting of textbooks and articles, have been reviewed. We focused on the more recent data about the changing epidemiology or pertussis in Scopus through the use of the MeSH-term words [pertussis] or [whooping cough] and [epidemiology] or [outbreak] or [resurgence], but our search was not restricted to this particular strategy; we also tried to find all of the most recent available data in the general field through other means. Results Primary and booster doses of the pertussis vaccine seem to partially control transmission of the disease, but despite the different preventive strategies available, pertussis continues to cause mortality and morbidity among high-risk groups. Conclusions Adding booster doses of acellular pertussis vaccine to the current national immunization practices with whole-cell vaccines for young adults and pregnant women seems to be a good option for controlling mortality and morbidity among high-risk groups such as very young infants. PMID:27729960

  4. Face aftereffects predict individual differences in face recognition ability.

    Science.gov (United States)

    Dennett, Hugh W; McKone, Elinor; Edwards, Mark; Susilo, Tirta

    2012-01-01

    Face aftereffects are widely studied on the assumption that they provide a useful tool for investigating face-space coding of identity. However, a long-standing issue concerns the extent to which face aftereffects originate in face-level processes as opposed to earlier stages of visual processing. For example, some recent studies failed to find atypical face aftereffects in individuals with clinically poor face recognition. We show that in individuals within the normal range of face recognition abilities, there is an association between face memory ability and a figural face aftereffect that is argued to reflect the steepness of broadband-opponent neural response functions in underlying face-space. We further show that this correlation arises from face-level processing, by reporting results of tests of nonface memory and nonface aftereffects. We conclude that face aftereffects can tap high-level face-space, and that face-space coding differs in quality between individuals and contributes to face recognition ability.

  5. A Fuzzy Obstacle Avoidance Controller Using a Lookup-Table Sharing Method and Its Applications for Mobile Robots

    Directory of Open Access Journals (Sweden)

    Jinwook Kim

    2011-11-01

    Full Text Available A Lookup‐Table (LUT based design enhances the processing speed of a fuzzy obstacle avoidance controller by reducing the operation time. Also, a LUT sharing method provides efficient ways of reducing the LUT memory size. In order to share the LUT which is used for a fuzzy obstacle avoidance controller, an idea of using a basis function is developed. As applications of the shared LUT‐based fuzzy controller, a laser‐sensor‐based fuzzy controller and an ultrasonic‐sensor‐based fuzzy controller are introduced in this paper. This paper suggests a LUT sharing method that reduces the LUT buffer size without a significant degradation of the performance. The LUT sharing method makes the buffer size independent of the fuzzy system

  6. Keeping Safe: Intra-individual Consistency in Obstacle Avoidance Behaviour Across Grasping and Locomotion Tasks.

    Science.gov (United States)

    Kangur, Karina; Billino, Jutta; Hesse, Constanze

    2017-01-01

    Successful obstacle avoidance requires a close coordination of the visual and the motor systems. Visual information is essential for adjusting movements in order to avoid unwanted collisions. Yet, established obstacle avoidance paradigms have typically either focused on gaze strategies or on motor adjustments. Here we were interested in whether humans show similar visuomotor sensitivity to obstacles when gaze and motor behaviour are measured across different obstacle avoidance tasks. To this end, we measured participants' hand movement paths when grasping targets in the presence of obstacles as well as their gaze behaviour when walking through a cluttered hallway. We found that participants who showed more pronounced motor adjustments during grasping also spent more time looking at obstacles during locomotion. Furthermore, movement durations correlated positively in both tasks. Results suggest considerable intra-individual consistency in the strength of the avoidance response across different visuomotor measures potentially indicating an individual's tendency to perform safe actions.

  7. Obstacle avoidance, visual detection performance, and eye-scanning behavior of glaucoma patients in a driving simulator: a preliminary study.

    Directory of Open Access Journals (Sweden)

    Rocío Prado Vega

    Full Text Available The objective of this study was to evaluate differences in driving performance, visual detection performance, and eye-scanning behavior between glaucoma patients and control participants without glaucoma. Glaucoma patients (n = 23 and control participants (n = 12 completed four 5-min driving sessions in a simulator. The participants were instructed to maintain the car in the right lane of a two-lane highway while their speed was automatically maintained at 100 km/h. Additional tasks per session were: Session 1: none, Session 2: verbalization of projected letters, Session 3: avoidance of static obstacles, and Session 4: combined letter verbalization and avoidance of static obstacles. Eye-scanning behavior was recorded with an eye-tracker. Results showed no statistically significant differences between patients and control participants for lane keeping, obstacle avoidance, and eye-scanning behavior. Steering activity, number of missed letters, and letter reaction time were significantly higher for glaucoma patients than for control participants. In conclusion, glaucoma patients were able to avoid objects and maintain a nominal lane keeping performance, but applied more steering input than control participants, and were more likely than control participants to miss peripherally projected stimuli. The eye-tracking results suggest that glaucoma patients did not use extra visual search to compensate for their visual field loss. Limitations of the study, such as small sample size, are discussed.

  8. The role of the amygdala in face perception and evaluation

    NARCIS (Netherlands)

    Todorov, A.T.

    2012-01-01

    Faces are one of the most significant social stimuli and the processes underlying face perception are at the intersection of cognition, affect, and motivation. Vision scientists have had a tremendous success of mapping the regions for perceptual analysis of faces in posterior cortex. Based on eviden

  9. Evaluation of the Revised Lagrangian Particle Model GRAL Against Wind-Tunnel and Field Observations in the Presence of Obstacles

    Science.gov (United States)

    Oettl, Dietmar

    2015-05-01

    A revised microscale flow field model has been implemented in the Lagrangian particle model Graz Lagrangian Model (GRAL) for computing flows around obstacles. It is based on the Reynolds-averaged Navier-Stokes equations in three dimensions and the widely used standard turbulence model. Here we focus on evaluating the model regarding computed concentrations by use of a comprehensive wind-tunnel experiment with numerous combinations of building geometries, stack positions, and locations. In addition, two field experiments carried out in Denmark and in the U.S were used to evaluate the model. Further, two different formulations of the standard deviation of wind component fluctuations have also been investigated, but no clear picture could be drawn in this respect. Overall the model is able to capture several of the main features of pollutant dispersion around obstacles, but at least one future model improvement was identified for stack releases within the recirculation zone of buildings. Regulatory applications are the bread-and-butter of most GRAL users nowadays, requiring fast and robust modelling algorithms. Thus, a few simplifications have been introduced to decrease the computational time required. Although predicted concentrations for the two field experiments were found to be in good agreement with observations, shortcomings were identified regarding the extent of computed recirculation zones for the idealized wind-tunnel building geometries, with approaching flows perpendicular to building faces.

  10. Virtual force field based obstacle avoidance and agent based intelligent mobile robot

    Science.gov (United States)

    Sarkar, Saurabh; Reynolds, Scott; Hall, Ernest

    2007-09-01

    This paper presents a modified virtual force based obstacle avoidance approach suited for laser range finder. The modified method takes advantage of the polar coordinate based data sent by the laser sensor by mapping the environment in a polar coordinate system. The method also utilizes a Gaussian function based certainty values to detect obstacle. The method successfully navigates through complex obstacles and reaches target GPS waypoints.

  11. Obstacle detection algorithm of low computational cost for Guanay II AUV

    OpenAIRE

    Galarza Bogotá, Cesar Mauricio; Prat Tasias, Jordi; Gomáriz Castro, Spartacus

    2016-01-01

    Obstacle detection is one of the most important stages in the obstacle avoidance system. This work is focused to explain the operation of a designed and implemented for the overall detection of objects with low computational cost strategy. This strategy of low computational cost is based on performing a spatial segmentation of the information obtained by the SONAR and determine the minimum distance between the SONAR (AUV) and the obstacle. Peer Reviewed

  12. Obstacle detection algorithm of low computational cost for Guanay II AUV

    OpenAIRE

    Galarza Bogotá, Cesar Mauricio; Prat Tasias, Jordi; Gomáriz Castro, Spartacus

    2016-01-01

    Obstacle detection is one of the most important stages in the obstacle avoidance system. This work is focused to explain the operation of a designed and implemented for the overall detection of objects with low computational cost strategy. This strategy of low computational cost is based on performing a spatial segmentation of the information obtained by the SONAR and determine the minimum distance between the SONAR (AUV) and the obstacle.

  13. Transition to Motherhood as an Immigrant: Risks and Obstacles

    Directory of Open Access Journals (Sweden)

    Ruveyde Aydin

    2017-09-01

    Full Text Available The process of transition to motherhood that brings along a number of vital changes may be full of risks and difficulties for immigrant mothers. Poverty, being unfamiliar with the language of the country that the mother migrated, inability of healthcare policies in covering healthcare expenses of immigrants, insufficiency of social assistance and loneliness may negatively affect health of mother and infant. Postpartum immigrant mothers are seen depression, anxiety, stress and social isolation because of these obstacles. Therefore, health care professionals, who provide care to immigrant mothers, should clarify immigrant mothers' religious, cultural beliefs and attitudes. Procurement of peer support is important by developing care programs special to immigrant mothers and ensuring immigrant women to come together. Increase in the number of translators in hospitals and prepara-tion of education materials in native language of mothers will improve the level of benefiting from healthcare services. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2017; 9(3.000: 250-262

  14. Investigation of obstacles against effective crisis management in earthquake

    Directory of Open Access Journals (Sweden)

    Mahmood Nekoei-Moghadam

    2016-03-01

    Full Text Available Floods, hurricanes, landslides, hurricanes, tornadoes, earthquakes are events that a large group of people on earth are affected. In December 2003, the residents of Bam, Iran experienced an earthquake that measured 6.6 on the Richter scale and destroyed more than 90% of the city. The purpose of this study was to investigate obstacles against effective crisis management with considering service received by individuals in the Bam earthquake. In this study, domestic journals, foreign dissertations in Persian bases such as Google scholar, Magiran, IranMedex, SID and in English bases such as PubMed, Web of Science, Google scholar were used. The results of this study showed that there were many problems in various aspects of planning including: lack of coherent programs, lack of attention to the needs of health care, poor coordination between agencies and organizations and lack of appropriate training of volunteers and people.

  15. An Analysis of Cultural Obstacles on English Learning

    Institute of Scientific and Technical Information of China (English)

    魏丽丽

    2014-01-01

    Language and culture can not be separated. It is impossible to learn language well if people do not master cultural back-ground. With the frequent communication between China and other nations throughout the world, cross-cultural communica-tive competence is put forward to be the ultimate goal of foreign language learning in China. However, in present situation, cul-tural factor has not gained its due place in students’English learning. Based on this circumstance, this paper analyzes the cultural obstacles on English learning from the aspects of listening, reading and communicating, and puts forward that while instructing English language, teachers of English should pay attention to and spread cultural background knowledge of English speaking na-tions to improve students’language comprehension ability and cross-cultural communicative competence.

  16. Governance Obstacles to Geothermal Energy Development in Indonesia

    Directory of Open Access Journals (Sweden)

    Matthew S. Winters

    2015-01-01

    Full Text Available Despite having 40 per cent of the world’s potential for geothermal power production, Indonesia exploits less than five per cent of its own geothermal resources. We explore the reasons behind this lagging development of geothermal power and highlight four obstacles: (1 delays caused by the suboptimal decentralisation of permitting procedures to local governments that have few incentives to support geothermal exploitation; (2 rent-seeking behaviour originating in the point-source nature of geothermal resources; (3 the opacity of central government decision making; and (4 a historically deleterious national fuel subsidy policy that disincentivised geothermal investment. We situate our arguments against the existing literature and three shadow case studies from other Pacific countries that have substantial geothermal resources. We conclude by arguing for a more centralised geothermal governance structure.

  17. Persona Usage in Software Development: Advantages and Obstacles

    DEFF Research Database (Denmark)

    Billestrup, Jane; Stage, Jan; Nielsen, Lene

    2014-01-01

    The Personas technique has been promoted as a strong tool for providing software developers with a better understanding of the prospective users of their software. This paper reports from a questionnaire survey regarding knowledge about Personas and their usage in software development companies....... The questionnaire survey was conducted in a limited geographical area to establish the extent of Personas usage within all companies in the chosen region and determine whether software development companies used Personas during the development process. Several issues were identified as reasons for either not using...... the technique or for poor application of it. The study showed that 55% of the respondents had never heard about Personas. Among those who had heard about the Personas technique, the following obstacles towards usage of the technique were identified: Lack of knowledge of the technique, lack of resources (time...

  18. Obstacles to performance in the South African autocomponents industry

    DEFF Research Database (Denmark)

    Granerud, Lise

    2003-01-01

    obstacles preventing further improvement of performance and competitiveness. Organisational behaviour has increasingly become important internationally in the understanding of firm development and learning in the recent years. This paper argues that it is crucial to take into account the behaviour...... behaviour in different ways hinders internal learning. These findings are contrasted with a third firm within the metal sector, which has a very different learning environment. The paper emphasises the importance of including the informal organisational behaviour in the understanding of how to develop...... the technological resources. The study investigates the physical resources, and the human and organisational resources, and relates these to the routines in the organisational behaviour, including formal and informal work practices and social relations at the shop floor in the understanding of what influence...

  19. EU Integration Process: Will Turkey Overcome the FDI Obstacles?

    Directory of Open Access Journals (Sweden)

    Mehmet Basar

    2006-06-01

    Full Text Available This paper analyses Turkey's performance in attracting foreign direct investment (FDI and highlights the key obstacles for FDI in Turkey. When compared with its main competitor countries, which includes the group of new EU member states and other candidate countries, it can be concluded that Turkey has a very low rate of FDI inflow. It can be argued that one of the major problems behind the low performance in FDI inflows is macroeconomic instability. In this paper we will also perform an empirical analysis to examine the relationship between FDIs and macroeconomic instability in the EU new member states and the candidate countries. According to the regression results, it was found that the GDP and openness have positive effects on the FDI, whereas current account balance and inflation have been found to be negative. On the other hand, the results related to external debt run opposite to our expectations.

  20. Avoiding obstacles by using a proximity infrared sensor skin

    Institute of Scientific and Technical Information of China (English)

    Cao Zhengcai; Fu Yili; Wu Qidi; Wang Shuguo; Wang Guangguo

    2007-01-01

    Placement and wiring of vast amount of sensor elements on the 3-dimensionally configured robot surface to form soft sensor skin is very difficult with the traditional technology, hi this paper we propose a new method to realize such a skin. By implanting infrared sensors array in an elastic body, we obtain an elastic and tough sensor skin that can be shaped freely. The developed sensor skin is a large-area, flexible array of infrared sensors with data processing capabilities. Depending on the skin electronics, it endows its carrier with an ability to sense its surroundings. The structure, the method of infrared sensor signal processing, and basic experiments of sensor skin are presented. The validity of the infrared sensor skin is investigated by preliminary obstacle avoidance trial.

  1. Fast and Robust Stereo Vision Algorithm for Obstacle Detection

    Institute of Scientific and Technical Information of China (English)

    Yi-peng Zhou

    2008-01-01

    Binocular computer vision is based on bionics, after the calibration through the camera head by double-exposure image synchronization, access to the calculation of two-dimensional image pixels of the three-dimensional depth information. In this paper, a fast and robust stereo vision algorithm is described to perform in-vehicle obstacles detection and characterization. The stereo algorithm which provides a suitable representation of the geometric content of the road scene is described, and an in-vehicle embedded system is presented. We present the way in which the algorithm is used, and then report experiments on real situations which show that our solution is accurate, reliable and efficient. In particular, both processes are fast, generic,robust to noise and bad conditions, and work even with partial occlusion.

  2. Understanding Supplier Resistance - Overcoming Obstacles to Supply Innovation

    Directory of Open Access Journals (Sweden)

    New Steve

    2014-11-01

    Full Text Available This paper explores an important but unexplored theme in the development of 'total quality' relationships in the supply chain: why suppliers may exhibit resistance to quality initiatives, and why what seems to customers as cooperation can appear as unwelcome interference or even exploitation to suppliers. This is a question of great relevance to all those seeking to understand current business practice, and also to those seeking to bring about practical improvements in supply chain quality. Too much of the supply chain and quality literature assumes the issue of supplier's compliance with customer initiatives is unproblematic (unable to understand this sentence; experience suggests it is one of the major obstacles in developing the quality-oriented, integrated supply chain.

  3. Microcontroller-based mobile robot positioning and obstacle avoidance

    Directory of Open Access Journals (Sweden)

    Aziza M. Zaki

    2014-05-01

    Full Text Available The use of mobile robots is growing in manufacturing facilities, hazardous materials handling, etc. Usually, several sensor systems are used in combination. The task of combining the information into a usable form, suitable for making navigation decisions, is known as sensor fusion. In this paper, the navigation system built on a mobile robot operating in a warehouse is presented focusing on the sensory system used. Hybrid navigation system that combines the perception and dead reckoning is used and gives satisfactory operation. A microcontroller system is designed to control the navigation of a mobile robot while avoiding obstacles. A system of 24 ultrasonic sensors was designed and the operation algorithms were described. The encoder and the ultrasonic sensors used are presented in detail together with the navigation system designed based on their operation.

  4. Investigation of obstacles against effective crisis management in earthquake

    Institute of Scientific and Technical Information of China (English)

    Mahmood Nekoei-Moghadam; Mohammadreza Amiresmaili; Zeynab Aradoei

    2016-01-01

    Floods, hurricanes, landslides, hurricanes, tornadoes, earthquakes are events that a large group of people on earth are affected. In December 2003, the residents of Bam, Iran experienced an earthquake that measured 6.6 on the Richter scale and destroyed more than 90% of the city. The purpose of this study was to investigate obstacles against effective crisis management with considering service received by individuals in the Bam earthquake. In this study, domestic journals, foreign dissertations in Persian bases such as Google scholar, Magiran, IranMedex, SID and in English bases such as PubMed, Web of Science, Google scholar were used. The results of this study showed that there were many problems in various aspects of planning including: lack of coherent programs, lack of attention to the needs of health care, poor coordination between agencies and organiza-tions and lack of appropriate training of volunteers and people.

  5. Knowledge Management in Accomodation: Infrastructure, Applications and Obstacles Encountered

    Directory of Open Access Journals (Sweden)

    Emel Bahar

    2011-06-01

    Full Text Available Contemporary administrations have to manage their knowledge in an effective and systematic way so that they can maintain both their existence and their competition advantages with long term differentiated superiority. As a result of globalization, the effects of the development in information technology on all sectors can also be observed in tourism sector. In this study, the applications of accommodation establishments, their knowledge management background, and the obstacles met in practice are determined. The benefits of information technologies in enterprises involved in this study have been seen in a concrete way and the necessary infrastructure have been identified. But human capital, organizational structure and organizational culture were inadequacies about knowledge management.

  6. Spatial heterogeneity and functional response: an experiment in microcosms with varying obstacle densities.

    Science.gov (United States)

    Hauzy, Céline; Tully, Thomas; Spataro, Thierry; Paul, Grégory; Arditi, Roger

    2010-07-01

    Spatial heterogeneity of the environment has long been recognized as a major factor in ecological dynamics. Its role in predator-prey systems has been of particular interest, where it can affect interactions in two qualitatively different ways: by providing (1) refuges for the prey or (2) obstacles that interfere with the movements of both prey and predators. There have been relatively fewer studies of obstacles than refuges, especially studies on their effect on functional responses. By analogy with reaction-diffusion models for chemical systems in heterogeneous environments, we predict that obstacles are likely to reduce the encounter rate between individuals, leading to a lower attack rate (predator-prey encounters) and a lower interference rate (predator-predator encounters). Here, we test these predictions under controlled conditions using collembolans (springtails) as prey and mites as predators in microcosms. The effect of obstacle density on the functional response was investigated at the scales of individual behavior and of the population. As expected, we found that increasing obstacle density reduces the attack rate and predator interference. Our results show that obstacles, like refuges, can reduce the predation rate because obstacles decrease the attack rate. However, while refuges can increase predator dependence, we suggest that obstacles can decrease it by reducing the rate of encounters between predators. Because of their opposite effect on predator dependence, obstacles and refuges could modify in different ways the stability of predator-prey communities.

  7. Free surface Hele-Shaw flows around an obstacle: A random walk simulation.

    Science.gov (United States)

    Bogoyavlenskiy, Vladislav A; Cotts, Eric J

    2004-01-01

    This paper presents computer simulations of pressure driven viscous flows that creep in two dimensions (Hele-Shaw cells). We model the time and spatial evolution of free liquid-gas interfaces perturbed by solid obstacles of various configurations such as wedges, steps, and ellipses. Our goal is to study short- and long-scale obstacle effects on the interface shape and velocity. Specific focus is given to the dynamics of a triple (gas-liquid-solid) contact line, which determines local wetting of obstacles. As a principal contribution, we derive a functional relationship between the contact line velocity and the obstacle geometry.

  8. On the debate about teleology in biology: the notion of "teleological obstacle"

    Directory of Open Access Journals (Sweden)

    Manuel Gustavo Leitão Ribeiro

    2015-12-01

    Full Text Available Among the epistemological obstacles described by Gaston Bachelard, we contend that unitary and pragmatic knowledge is correlated to the teleological categories of Ernst Mayr and is the basis for prevailing debate on the notion of "function" in biology. Given the proximity of the aspects highlighted by these authors, we propose to associate the role of teleological thinking in biology and the notion of unitary and pragmatic knowledge as an obstacle to scientific knowledge. Thus, teleological thinking persists acting as an epistemological obstacle in biology, according to Bachelardian terminology. Our investigation led us to formulate the "teleological obstacle," which we consider important for the future of biology and possibly other sciences.

  9. On the debate about teleology in biology: the notion of "teleological obstacle".

    Science.gov (United States)

    Ribeiro, Manuel Gustavo Leitão; Larentis, Ariane Leites; Caldas, Lúcio Ayres; Garcia, Tomás Coelho; Terra, Letícia Labati; Herbst, Marcelo Hawrylak; Almeida, Rodrigo Volcan

    2015-12-01

    Among the epistemological obstacles described by Gaston Bachelard, we contend that unitary and pragmatic knowledge is correlated to the teleological categories of Ernst Mayr and is the basis for prevailing debate on the notion of "function" in biology. Given the proximity of the aspects highlighted by these authors, we propose to associate the role of teleological thinking in biology and the notion of unitary and pragmatic knowledge as an obstacle to scientific knowledge. Thus, teleological thinking persists acting as an epistemological obstacle in biology, according to Bachelardian terminology. Our investigation led us to formulate the "teleological obstacle," which we consider important for the future of biology and possibly other sciences.

  10. Experimental Study on Performance of Fume Hood with Obstacle Located inside%内置有障碍物时排风柜性能的实验研究

    Institute of Scientific and Technical Information of China (English)

    王新林; 刘东; 程勇; 王康; 胡强

    2012-01-01

    排风柜性能受到很多因素影响。本文采用实验方法分析了排风柜拉门高度500mm和拉门全开,不同面风速时,柜内障碍物对排风柜性能的影响。实验结果表明:排风柜面风速分布均匀性与面风速大小和柜内障碍物阻挡率呈线性函数关系;面风速越小,障碍物阻挡率越大,排风柜性能和面风速分布均匀性更差。%The performance of fume hood is related to many factors.Experimental method is used to research on the performance of obstacle located inside fume hood when the height of sash is at 500mm and maximum opening under different face velocity.The results show that the performance of fume hood is linearly related to face velocity and the area ratio of open of fume hood blocked by obstacles;the uniformity of face velocity of fume hood becomes worsen when face velocity is lower and the area ratio of open of fume hood blocked by obstacles is greater.

  11. Automated Face Recognition System

    Science.gov (United States)

    1992-12-01

    atestfOl.feature-vectjJ -averageljJ); for(j=l; <num-coefsj++) for(i= 5 num-train-faces;i++) sdlQjI -(btrainhil.feaure..vecU1- veagU (btraintil.feature- vecU ... vecU ])* (atest(O1.feature-vecUJ - btrain[iI.feature- vecU ]) + temp; btrain(ii.distance = sqrt ( (double) temp); I**** Store the k-nearest neighbors rank

  12. Auto Industry Faces Change

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A number of indicators show that China's auto industry is facing a new round of large-scale restructuring. When the global auto industry was undergoing reorganization 10 years ago, China's auto industry was in its early stages, acting in a relatively closed market, and thus it missed out on that important event. However, the situation is different today. In the past decade, China's auto industry has grown at a rapid pace. While the world's major transnational companies are

  13. Visual adaptation of the perception of "life": animacy is a basic perceptual dimension of faces.

    Science.gov (United States)

    Koldewyn, Kami; Hanus, Patricia; Balas, Benjamin

    2014-08-01

    One critical component of understanding another's mind is the perception of "life" in a face. However, little is known about the cognitive and neural mechanisms underlying this perception of animacy. Here, using a visual adaptation paradigm, we ask whether face animacy is (1) a basic dimension of face perception and (2) supported by a common neural mechanism across distinct face categories defined by age and species. Observers rated the perceived animacy of adult human faces before and after adaptation to (1) adult faces, (2) child faces, and (3) dog faces. When testing the perception of animacy in human faces, we found significant adaptation to both adult and child faces, but not dog faces. We did, however, find significant adaptation when morphed dog images and dog adaptors were used. Thus, animacy perception in faces appears to be a basic dimension of face perception that is species specific but not constrained by age categories.

  14. Human Wagering Behavior Depends on Opponents' Faces

    Science.gov (United States)

    Schlicht, Erik J.; Shimojo, Shinsuke; Camerer, Colin F.; Battaglia, Peter; Nakayama, Ken

    2010-01-01

    Research in competitive games has exclusively focused on how opponent models are developed through previous outcomes and how peoples' decisions relate to normative predictions. Little is known about how rapid impressions of opponents operate and influence behavior in competitive economic situations, although such subjective impressions have been shown to influence cooperative decision-making. This study investigates whether an opponent's face influences players' wagering decisions in a zero-sum game with hidden information. Participants made risky choices in a simplified poker task while being presented opponents whose faces differentially correlated with subjective impressions of trust. Surprisingly, we find that threatening face information has little influence on wagering behavior, but faces relaying positive emotional characteristics impact peoples' decisions. Thus, people took significantly longer and made more mistakes against emotionally positive opponents. Differences in reaction times and percent correct were greatest around the optimal decision boundary, indicating that face information is predominantly used when making decisions during medium-value gambles. Mistakes against emotionally positive opponents resulted from increased folding rates, suggesting that participants may have believed that these opponents were betting with hands of greater value than other opponents. According to these results, the best “poker face” for bluffing may not be a neutral face, but rather a face that contains emotional correlates of trustworthiness. Moreover, it suggests that rapid impressions of an opponent play an important role in competitive games, especially when people have little or no experience with an opponent. PMID:20657772

  15. Applying Artificial Neural Networks for Face Recognition

    Directory of Open Access Journals (Sweden)

    Thai Hoang Le

    2011-01-01

    Full Text Available This paper introduces some novel models for all steps of a face recognition system. In the step of face detection, we propose a hybrid model combining AdaBoost and Artificial Neural Network (ABANN to solve the process efficiently. In the next step, labeled faces detected by ABANN will be aligned by Active Shape Model and Multi Layer Perceptron. In this alignment step, we propose a new 2D local texture model based on Multi Layer Perceptron. The classifier of the model significantly improves the accuracy and the robustness of local searching on faces with expression variation and ambiguous contours. In the feature extraction step, we describe a methodology for improving the efficiency by the association of two methods: geometric feature based method and Independent Component Analysis method. In the face matching step, we apply a model combining many Neural Networks for matching geometric features of human face. The model links many Neural Networks together, so we call it Multi Artificial Neural Network. MIT + CMU database is used for evaluating our proposed methods for face detection and alignment. Finally, the experimental results of all steps on CallTech database show the feasibility of our proposed model.

  16. Decoding of faces and face components in face-sensitive human visual cortex

    Directory of Open Access Journals (Sweden)

    David F Nichols

    2010-07-01

    Full Text Available A great challenge to the field of visual neuroscience is to understand how faces are encoded and represented within the human brain. Here we show evidence from functional magnetic resonance imaging (fMRI for spatially distributed processing of the whole face and its components in face-sensitive human visual cortex. We used multi-class linear pattern classifiers constructed with a leave-one-scan-out verification procedure to discriminate brain activation patterns elicited by whole faces, the internal features alone, and the external head outline alone. Furthermore, our results suggest that whole faces are represented disproportionately in the fusiform cortex (FFA whereas the building blocks of faces are represented disproportionately in occipitotemporal cortex (OFA. Faces and face components may therefore be organized with functional clustering within both the FFA and OFA, but with specialization for face components in the OFA and the whole face in the FFA.

  17. Face-space: A unifying concept in face recognition research.

    Science.gov (United States)

    Valentine, Tim; Lewis, Michael B; Hills, Peter J

    2016-10-01

    The concept of a multidimensional psychological space, in which faces can be represented according to their perceived properties, is fundamental to the modern theorist in face processing. Yet the idea was not clearly expressed until 1991. The background that led to the development of face-space is explained, and its continuing influence on theories of face processing is discussed. Research that has explored the properties of the face-space and sought to understand caricature, including facial adaptation paradigms, is reviewed. Face-space as a theoretical framework for understanding the effect of ethnicity and the development of face recognition is evaluated. Finally, two applications of face-space in the forensic setting are discussed. From initially being presented as a model to explain distinctiveness, inversion, and the effect of ethnicity, face-space has become a central pillar in many aspects of face processing. It is currently being developed to help us understand adaptation effects with faces. While being in principle a simple concept, face-space has shaped, and continues to shape, our understanding of face perception.

  18. A Study of Junior Students'Cross- Culture Obstacles in English Reading Comprehension%A Study of Junior Students' Cross-Culture Obstacles in English Reading Comprehension

    Institute of Scientific and Technical Information of China (English)

    朱雅琴

    2015-01-01

    This paper will research Junior students' cross-cultural obstacles in English reading from the perspective of culture background,Eliminating Junior students'cross-cultural barriers can improve intercultural communication competent.

  19. ERROR REDUCTION IN ADAPTIVE FINITE ELEMENT APPROXIMATIONS OF ELLIPTIC OBSTACLE PROBLEMS

    Institute of Scientific and Technical Information of China (English)

    Dietrich Braess; Carsten Carstensen; Ronald H.W. Hoppe

    2009-01-01

    We consider an adaptive finite element method (AFEM) for obstacle problems associated with linear second order elliptic boundary value problems and prove a reduction in the energy norm of the discretization error which leads to R-linear convergence. This result is shown to hold up to a consistency error due to the extension of the discrete multipliers (point functionals) to H-1 and a possible mismatch between the continuous and discrete coincidence and noncoincidence sets. The AFEM is based on a residual-type error estimator consisting of element and edge residuals. The a posteriori error analysis reveals that the significant difference to the unconstrained case lies in the fact that these residuals only have to be taken into account within the discrete noncoincidence set. The proof of the error reduction property uses the reliability and the discrete local efficiency of the estimator as well as a perturbed Galerkin orthogonality. Numerical results are given illustrating the performance of the AFEM.

  20. Overcoming obstacles to implementing methadone maintenance therapy for prisoners: Implications for policy and practice

    Science.gov (United States)

    McKenzie, Michelle; Nunn, Amy; Zaller, Nickolas D.; Bazazi, Alexander R.; Rich, Josiah D.

    2010-01-01

    More than 2.4 million people are currently incarcerated in the United States, many as a result of drug-related offenses. In addition, more than 200,000 active heroin addicts pass through the correctional system annually. New evidence suggests that both providing prisoners with referrals for community-based methadone programs and providing methadone prior to release reduces recidivism and adverse health and social consequences associated with drug use. This article reports the programmatic challenges associated with initiating methadone treatment in the Rhode Island correctional system. Significant obstacles to implementing methadone treatment include: stigma associated with pharmacological treatment, misconceptions regarding the nature of opioid addiction, logistics of control and storage of methadone, increased work load for nursing staff, and general safety and control concerns. The authors discuss strategies to address these barriers and conclude that providing methadone prior to inmate release is a feasible intervention with the potential to mitigate drug-related health and social harms. PMID:19736902