• 제목/요약/키워드: Seek Control

검색결과 359건 처리시간 0.024초

Absolute Positioning System for Mobile Robot Navigation in an Indoor Environment (ICCAS 2004)

  • Yun, Jae-Mu;Park, Jin-Woo;Choi, Ho-Seek;Lee, Jang-Myung
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2004년도 ICCAS
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    • pp.1448-1451
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    • 2004
  • Position estimation is one of the most important functions for the mobile robot navigating in the unstructured environment. Most of previous localization schemes estimate current position and pose of mobile robot by applying various localization algorithms with the information obtained from sensors which are set on the mobile robot, or by recognizing an artificial landmark attached on the wall, or objects of the environment as natural landmark in the indoor environment. Several drawbacks about them have been brought up. To compensate the drawbacks, a new localization method that estimates the absolute position of the mobile robot by using a fixed camera on the ceiling in the corridor is proposed. And also, it can improve the success rate for position estimation using the proposed method, which calculates the real size of an object. This scheme is not a relative localization, which decreases the position error through algorithms with noisy sensor data, but a kind of absolute localization. The effectiveness of the proposed localization scheme is demonstrated through the experiments.

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Haptics for Human-Machine Interaction at The Johns Hopkins University

  • Okamura, Allison M.;Chang, Sung-Ouk
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.2676-2681
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    • 2003
  • The Haptic Exploration Laboratory at The Johns Hopkins University is currently exploring many problems related to haptics (force and tactile information) in human-machine systems. We divide our work into two main areas: virtual environments and robot-assisted manipulation systems. Our interest in virtual environments focuses on reality-based modeling, in which measurements of the static and dynamic properties of actual objects are taken in order to produce realistic virtual environments. Thus, we must develop methods for acquiring data from real objects and populating pre-defined models. We also seek to create systems that can provide active manipulation assistance to the operator through haptic, visual, and audio cues. These systems may be teleoperated systems, which allow human users to operate in environments that would normally be inaccessible due to hazards, distance, or scale. Alternatively, cooperative manipulation systems allow a user and a robot to share a tool, allowing the user to guide or override the robot directly if necessary. Haptics in human-machine systems can have many applications, such as undersea and space operations, training for pilots and surgeons, and manufacturing. We focus much of our work on medical applications.

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Secure Beamforming with Artificial Noise for Two-way Relay Networks

  • Li, Dandan;Xiong, Ke;Du, Guanyao;Qiu, Zhengding
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제7권6호
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    • pp.1418-1432
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    • 2013
  • This paper studies the problem of secure information exchange between two sources via multiple relays in the presence of an eavesdropper. To this end, we propose a relay beamforming scheme, i.e., relay beamforming with artificial noise (RBwA), where the relay beamforming vector and the artificial noise vector are jointly designed to maintain the received signal-to-interference-ratio (SINR) at the two sources over a predefined Quality of Service (QoS) threshold while limiting the received SINR at the eavesdropper under a predefined secure threshold. For comparison, the relay beamforming without artificial noise (RBoA) is also considered. We formulate two optimization problems for the two schemes, where our goal is to seek the optimal beamforming vector to minimize the total power consumed by relay nodes such that the secrecy of the information exchange between the two sources can be protected. Since both optimization problems are nonconvex, we solve them by semidefinite program (SDP) relaxation theory. Simulation results show that, via beamforming design, physical layer secrecy of two-way relay networks can be greatly improved and our proposed RBwA outperforms the RBoA in terms of both low power consumption and low infeasibility rate.

차세대 품질 서비스 제공을 위한 지능형 MPLS 트래픽엔지니어링 서버 시스템 (Intelligent MPLS TE Server System for Next generation QoS Services)

  • 최태상;윤승현;정형석;김창훈;박정숙;이병준;정태수
    • 대한전자공학회논문지TC
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    • 제40권10호
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    • pp.129-137
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    • 2003
  • 인터넷이 최선형 서비스 망에서 양질의 서비스를 제공하기 위해 필수적인 통신 기반 수단으로 진화되어가고 있으며 이러한 서비스론 제공하는 것이 매우 경쟁적으로 되어감에 따라 대규모 NSP나 ISP들은 그들의 망의 성능과 효율적인 자원의 활용에 대해 더욱 관심을 기울이게 되었다. 이러한 현상은 자연스럽게 서비스 제공자들이 트래픽엔지니어링 기술에서 해답을 찾는 환경으로 유도하였다. 본 논문은 대규모 MPLS기반 IP 망에서 적용되어 트래픽 측정, 분석, 모델링 및 제어를 할 수 있는 트래픽엔지니어링 솔루션을 제안한다.

ASP(Application Service Provider) 서비스 사용자의 재구매 의사와 조직 이익에 미치는 영향요인 연구 (A study on the factors influencing the ASP service users' repurchase intent and organization benefits)

  • 김경규;신호경;김수현
    • Journal of Information Technology Applications and Management
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    • 제17권1호
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    • pp.55-81
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    • 2010
  • ASP service users' needs for flexible and customized services to deal with changes in business environments and user contexts seems to be appealing due to the progress of technology and IT paradigm such as ubiquitous computing and web 2.0. Through the lens of expectancy confirmation and flexibility, we explored factors that influence users' repurchase intent and organizational benefit in ASP services. With an empirical study, we examined information quality, service quality, flexibility, customization, user satisfaction, trust in ASP services can contribute to the repurchase intent and organizational benefit. In addition to, business type and company size are added to the research model as control variables for user satisfaction, trust, and repurchase intent. Our findings suggested that the service quality and flexibility significantly were cruicial determinant of user satisfaction in ASP services. Furthermore, user satisfaction significantly influenceS repurchase intent, and organization benefits were affected by repurchase intent. This study has important implications for academic researchers and practitioners who seek to understand factors that affect ASP service users' repurchase intent and organization benefits.

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우리나라의 개인정보 보호제도 분석 - 인증 및 평가제도와 개인식별번호를 중심으로 - (Analysis of Personal Information Protection System in Korea - Focus on Certification & Evauation System and Personal Identification Number -)

  • 김민천
    • 정보화정책
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    • 제23권4호
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    • pp.38-58
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    • 2016
  • 빠르게 변화하는 인터넷 환경과 미디의 변화는 온라인상에서 소통이라는 새로운 커뮤니케이션 방식을 만들고 있다. 누리꾼들은 온라인상에서 이전보다 더 많은 서비스를 제공받고, 이런 서비스를 통해 서로가 어려움 없이 소통할 수 있게 되었다. 하지만 이런 변화를 통해 얻어진 소통의 자유 확대는 이전보다 더 많은 개인 정보의 노출과 더 쉬운 개인 정보의 유출로 이어지고 있다. 더 큰 문제는 지금의 상황에서 개인 정보 유출을 통제하는 것이 과거보다 더 어렵게 되었다는 것이다. 우리 정부는 지속적으로 발생하는 개인정보 유출 사건을 해결하고 예방하기 위해서 개인정보 보호와 관련된 여러 정책들을 개발하고 시행하고 있다. 이 연구는 이렇게 시행되고 있는 개인정보 보호제도의 문제점을 찾아내고 대안을 모색하고자 한다.

매도인의 하자물품책임 면책약관의 규제에 관한 비교연구 (Regulating Exclusion Clauses of the Seller's Liability for Non-Conforming Goods: Comparative Accounts)

  • 이병문
    • 무역상무연구
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    • 제32권
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    • pp.29-56
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    • 2006
  • This article primarily concerns the various aspects of the rules to control express terms particularly in standard form which seek to absolve either wholly or in part from the seller's liability for non-conforming goods. It describes and analyzes in detail how English law regulates such terms. In this analysis, it places the following questions; first, whether each jurisdiction treats the seller's liability for non-conformity in quality and quantity as mandatory rules, second, if it does, to what extent it is treated so and third, if not, in what way it controls the seller's attempt to exclude or restrict his liability for non-conformity in quality and quantity. In addition, it attempts to compare the rules under English law with those under Korean law and to evaluate them in light of the discipline of comparative law. In an attempt to evaluate them, it asks the question of whether a solution from one jurisdiction may facilitate the systematic development and reform of another jurisdiction. The evaluation is based upon the idea that the problems of fairness associated with the use of standard terms occur where the customer is unfairly taken by surprise due to his ignorance of the terms, or where even if he knows of the substance of the terms and objects to it, he is met with a take-it-or-leave-it situation.

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체재형 가족농원 이용자의 요구분석 및 개선방안 (Dweller's Requirements Analysis for Improving Community Garden with Log House in Rural Areas)

  • 박덕병;손은호;김경희
    • 한국지역사회생활과학회지
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    • 제20권1호
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    • pp.33-49
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    • 2009
  • Community gardens with log house in rural areas as a rural growth tool are able to promote rural-urban exchange and adapt to current market mechanisms by means of communication and promotion techniques. It is important to know that what community garden's users seek for their benefits and demand for well-established and settled down. The primary purpose of this study was to examine the needs of dwellers to live their community gardens so as to provide a better understanding of community gardens in Korea. An open-ended questionnaire survey was obtained from ten householders on community gardens in the study area. The results show that there needs to establish facilities such as small storehouse for farming appliances and barbecue area, and to set up the regulation to control a loud talking and sing until late night. We suggest that the government supports to help dwellers consider their needs to be comfortable on their gardening plots.

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자연환기가 가능한 서울시 공동주택의 하절기 실내 온열 쾌적성 평가 (Evaluation of the Indoor Thermal Comfort in Naturally Ventilated Apartment During Summer)

  • 이승재;정창헌;황석호;김태연;이승복
    • KIEAE Journal
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    • 제10권4호
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    • pp.59-66
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    • 2010
  • Natural ventilation is major strategy of 'sustainable building'. It aims to supply fresh air to the indoor, and to remove heat from the indoor during summer. In the latter point of view, natural ventilation can be grouped into two main strategies, daytime ventilation and night cooing. If we take advantage of these two natural ventilation strategies, indoor thermal comfort can be significantly improved. This study focused on grasping the current situation and problem of indoor thermal comfort of the naturally ventilated residential buildings to seek for direction of later studies. Additionally, thermal comfort of residence where the interior blind and exterior insulation were applied was analyzed. It was analyzed that the percentage of the time which satisfy the indoor acceptable operative temperature during summer was 90 ~ 95% and the heat control performance of natural ventilation has a limitation. When the interior blind and exterior insulation were applied, indoor thermal comfort was significantly improved. However, it still need more improvement.

불변 모멘트를 이용한 반도체 IC 리드 불량 검사 알고리즘 (The Inspection Algorithm using Invariant Moment for the Detection of Lead Faults of Semiconductor IC)

  • 이길휘;김준식
    • 한국정보처리학회논문지
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    • 제5권10호
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    • pp.2737-2749
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    • 1998
  • 최근의 생산자동화 설비에서 시각시스템을 이용한 검사의 중요성이 증가되고 있다.본 연구에서는 시각시스템을 이용한 반도체 외관검사 방법을 제안하였다. 기존의 연구가 특징점을 통한 칩의 위치 및 기울어짐에 집중되어 있으나 본 연구에서는 물체 영역분할 방법으로 검사 대상의 리드영역분할 및 리드 추출을 제안하였으며, 불량 검사 방법으로 치수에 의한 검사방법이 주를 이루나 본 연구에서는 모멘트를 이용한 불량 빈도에 의한 단계적 검사 방법을 제안하였다. 기존의 방법과 비교실험에서 제안 방법의 영역분할 방법과 순차적 방법의 우수성과 불변 모멘트를 이용한 검사의 유용성을 입증하였다.

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