• 제목/요약/키워드: collective coordinate

검색결과 11건 처리시간 0.029초

Current-Induced Magnetic Domain-Wall Motion by Spin Transfer Torque: Collective Coordinate Approach with Domain-Wall Width Variation

  • Jung, Soon-Wook;Lee, Hyun-Woo
    • Journal of Magnetics
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    • 제12권1호
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    • pp.1-6
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    • 2007
  • The spin transfer torque generated by a spin-polarized current can induce the shift of the magnetic domain-wall position. In this work, we study theoretically the current-induced domain-wall motion by using the collective coordinate approach [Gen Tatara and Hiroshi Kohno, Phys. Rev. Lett. 92, 86601 (2004)]. The approach is extended to include not only the domain-wall position and the polarization angle changes but also the domain-wall width variation. It is demonstrated that the width variation affects the critical current.

A study on village economic cooperative in the city of China

  • Chen, Lifeng;Jin, Shanyue
    • International Journal of Advanced Culture Technology
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    • 제8권3호
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    • pp.1-9
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    • 2020
  • According to the 2012 social blue book released by the Chinese Academy of Social Sciences, China's urban population reached 50% in 2011. With the migration from marriage and new household registration, many urban collective assets have been formed in cities. Due to the unclear property rights and the emptiness of the main body, the distribution of collective assets mostly depends on the village cadres. The central government is preparing relevant laws and regulations to fill this legal gap, while the scheme of restructuring is decided by the villagers' vote, the local government coordinate the land acquisition and management. With the process of urbanization, a large number of second-generation of demolition studied abroad, which has attracted worldwide attention. In addition to the huge amount of compensation, due to the continuous rising of the land price, the value of the collective property and enterprises on the land also keep rising, the management agency of these assets is named village economic cooperative. This paper seeks to analyze the current status and future direction of these wealthy organizations, propose solutions to some existing problems.

사회적 구성'의 수학교육적 의미에 관한 고찰 (A Study on the Meaning of 'Social Construction' in Mathematics Education)

  • 홍진곤
    • 한국수학교육학회지시리즈A:수학교육
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    • 제41권3호
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    • pp.329-339
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    • 2002
  • This study analyzes the epistemological meaning of‘social construction’in mathematical instruction. The perspective that consider the cognition of mathematical concept as a social construction is explained by a cyclic scheme of an academic context and a school context. Both of the contexts require a public procedure, social conversation. However, there is a considerable difference that in the academic context it is Lakatos' ‘logic of mathematical discovery’In the school context, it is Vygotsky's‘instructional and learning interaction’. In the situation of mathematics education, the‘society’which has an influence on learner's cognition does not only mean‘collective members’, but‘form of life’which is constituted by the activity with purposes, language, discourse, etc. Teachers have to play a central role that guide and coordinate the educational process involving interactions with learners in this context. We can get useful suggestions to mathematics education through this consideration of the social contexts and levels to form didactical situations of mathematics.

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시각기반 센서 네트워크를 이용한 이동로봇의 위치 추정 (Mobile Robot Localization using Ubiquitous Vision System)

  • 누엔수안다오;김치호;유범재
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 D
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    • pp.2780-2782
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    • 2005
  • In this paper, we present a mobile robot localization solution by using a Ubiquitous Vision System (UVS). The collective information gathered by multiple cameras that are strategically placed has many advantages. For example, aggregation of information from multiple viewpoints reduces the uncertainty about the robots' positions. We construct UVS as a multi-agent system by regarding each vision sensor as one vision agent (VA). Each VA performs target segmentation by color and motion information as well as visual tracking for multiple objects. Our modified identified contractnet (ICN) protocol is used for communication between VAs to coordinate multitask. This protocol raises scalability and modularity of thesystem because of independent number of VAs and needless calibration. Furthermore, the handover between VAs by using ICN is seamless. Experimental results show the robustness of the solution with respect to a widespread area. The performance in indoor environments shows the feasibility of the proposed solution in real-time.

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인터넷 쇼핑몰에서 효율적인 상품 검색을 위한 가시화방법 (A Visualization Method for the Efficient Product Searching in Internet Shopping Mall)

  • 황보 택근;이수진
    • 인터넷정보학회논문지
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    • 제6권5호
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    • pp.111-121
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    • 2005
  • 전자상거래의 규모가 증가함에 따라 제공되는 상품의 정보와 서비스의 내용도 점차 다양해지고 있지만, 기존 쇼핑몰은 사용자에게 상품 정보를 일괄적인 나열방식으로 제공하기 때문에 사용자가 원하는 상품을 선택하기 위해서는 많은 노력과 시간이 소요된다. 본 논문에서는 속성 탐색기(feature inquirer)와 평행좌표(parallel coordinates)를 이용한 정보 가시화 기법을 적용하여 사용자에게 편리한 인터페이스를 제공함으로써 원하는 상품을 쉽게 검색할 수 있도록 하고, 상품의 효율적인 비교 검색을 통하여 정확한 상품선택이 이루어지도록 하는 방법을 제안하였다. 제안하는 검색 기법의 효율성을 검증하기 위해 피험자를 대상으로 검색 소요시간과 마우스 조작 횟수를 비교하여 타당성을 검증하였다.

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액체연료 액적군 의 비정상 집단연소 (Non-Steady Group Combustion of Liquid Fuel Droplets)

  • 김호영
    • 대한기계학회논문집
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    • 제8권6호
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    • pp.544-552
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    • 1984
  • 본 연구에서는 Chiu et al.의 집단연소이론에 대한 비정상집단연소모델(non- steady group combustion model)을 개발, 정지된 액적군에서 초기 액적들의 분포상태, 즉 초기액적들의 크기, 수밀도 및 액적군의 크기에 따른 연소시간, 연소형태 및 특성 과 화염의 성질등을 비정상 상태하에서 이론적인 모델을 통하여 고찰한다.

인체 흉상 복제를 위한 역공학 시스템 (A reverse engineering system for reproducing a 3D human bust)

  • 최회련;전용태;장민호;노형민;박세형
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2001년도 춘계학술대회 논문집
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    • pp.15-19
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    • 2001
  • A dedicated reverse engineering(RE) system for rapid manufacturing of human head in a 3D bust has been developed. The first step in the process is to capture the surface details of a human head and shoulder by three scanners based upon the digital moire fringe technique. Then the multiple scans captured from different angles are aligned and merged into a single polygonal mesh, and the aligned data set is refined by smoothing, subdividing or hole filling process. Finally, the refined data set is sent to a 4-axis computer numerically control(NC) machine to manufacture a replica. In this paper, we mainly describe on the algorithms and software for aligning multiple data sets. The method is based on the recently popular Iterative Closest Point(ICP) algorithm that aligns different polygonal meshes into one common coordinate system. The ICP algorithm finds the nearest positions on one scan to a collection of points on the other scan by minimizing the collective distance between different scans. We also integrate some heuristics into the ICP to enhance the aligning process. A typical example is presented to validate the system and further research work is also discussed.

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빌딩 에너지시스템 통합네트워크 구축에 관한 연구 (The Novel Configuration of Integrated Network for Building Energy System)

  • 홍원표
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2008년도 추계학술대회 논문집
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    • pp.229-234
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    • 2008
  • The new millennium has started with several innovations driven by fast evolution of the technologies in energy sector. A strong impulse towards the diffusion of new economical efficient technologies regulatory incentives related to energy production from renewable source and a small scale building trigeneration and to promotion of more sustainable environmental-friendly generation solutions, the evolution of electricity markets, more and more binding local emission constraints, and the need for improving the security of supply to reduce the energy system vulnerability. The 24 percentage energy quantify of total energy consumption consumes in commercial buildings and residential houses and the 30% portion of total $CO_2$ emissions covers also in the commercial buildings and residential houses sector. To cope with efficiently this energy sinuation in building sector, Building microgrid or building tooling, heating & power(BCHP) system has been interested in recent day due to meeting thermal and electric energy requirements efficiently and with appropriate energy quality. A multi agent system is a collective of intelligent agents that communicate with each other and work cooperatively to achieve common goals. Also, it is to medicate and coordinate communication between Control Areas and Security Coordinators for teal-time control of the BCHP system and the power pid. In this new circumstance, it is very important to integrate the power and energy delivery system and the information system(communication, networks, and intelligent equipment) that controls it. Therefore, development of smart control modules with open communication protocol and seamlessly interchange the data and information between control network and data network including extranet and intranet give a great meanings. We designed and developed the TCP/IP-CAN IED agent modules and ModBus./LonTalk/(TCP/IP) IED agent ones to configure the multi-agent system based smart energy network of commercial buildings and also intelligent algorithms for inverter fault diagnostics which ran be operated in control level or agent level network.

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