• 제목/요약/키워드: Bottom-Up

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상황 정보 기반 양방향 추론 방법을 이용한 이동 로봇의 물체 인식 (Object Recognition for Mobile Robot using Context-based Bi-directional Reasoning)

  • 임기현;류광근;서일홍;김종복;장국현;강정호;박명관
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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    • pp.6-8
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    • 2007
  • In this paper, We propose reasoning system for object recognition and space classification using not only visual features but also contextual information. It is necessary to perceive object and classify space in real environments for mobile robot. especially vision based. Several visual features such as texture, SIFT. color are used for object recognition. Because of sensor uncertainty and object occlusion. there are many difficulties in vision-based perception. To show the validities of our reasoning system. experimental results will be illustrated. where object and space are inferred by bi -directional rules even with partial and uncertain information. And the system is combined with top-down and bottom-up approach.

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Bottom-Up Segmentation Based Robust Shape Matching in the Presence of Clutter and Occlusion

  • Joo, Han-Byul;Jeong, Ye-Keun;Kweon, In-So
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 2009년도 IWAIT
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    • pp.307-310
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    • 2009
  • In this paper, we present a robust shape matching approach based on bottom-up segmentation. We show how over-segmentation results can be used to overcome both ambiguity of contour matching and occlusion. To measure the shape difference between a template and the object in the input, we use oriented chamfer matching. However, in contrast to previous work, we eliminate the affection of the background clutters before calculating the shape differences using over-segmentation results. By this method, we can increase the matching cost interval between true matching and false matching, which gives reliable results. Finally, our experiments also demonstrate that our method is robust despite the presence of occlusion.

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농촌지역개발 민간컨설팅회사 경영성과 결정요인 (The Determinants of Business on The Private Consulting Firms of Rural Development)

  • 김정태
    • 농촌계획
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    • 제19권1호
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    • pp.221-231
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    • 2013
  • The purpose of this study is to investigate the business performance determinants of private consulting firms supporting bottom-up local development projects in rural areas. Under the shortage of well-trained rural development professionals, Private consulting firms support rural development projects driven by the residents. Considering the important role for consulting firms to play in the success in rural development projects, it becomes necessary to review the circumstances of consulting market on rural development projects. This study targeted 80 companies that are listed in the book rural development consulting firms. Analysis showed that factors influencing the business performance are not professional competencies but other external factors. The implications based on the above results need to be considered for policy-making to ensure that consulting company selection must be guaranteed of the consulting firms'capability by detailed fields of consulting firms' capability, and the training system for rural development experts must be formed.

Development of Practical Data Mining Methods for Database Summarization

  • Lee, Do-Heon
    • 정보기술과데이타베이스저널
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    • 제4권2호
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    • pp.33-45
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    • 1998
  • Database summarization is the procedure to obtain generalized and representative descriptions expressing the content of a large amount of database at a glance. We present a top-down summary refinement procedure to discover database summaries. The procedure exploits attribute concept hierarchies that represent ISA relationships among domain concepts. It begins with the most generalized summary and proceeds to find more specialized ones by stepwise refinements. This top-down paradigm reveals at least two important advantages compared to the previous bottom-up methods. Firstly, it provides a natural way of reflecting the user's own discovery preference interactively. Secondly, it does not produce too large intermediate result that makes it hard for the bottom-up approach to be applied in practical environment. The proposed procedure can also be easily extended for distributed databases. Information content measure of a database summary is derived in order to identify more informative summaries among the discovered results.

Carbon Nanotube Reinforced Metal Matrix Nanocomposites via Equal Channel Angular Pressing

  • Quang, Pham;Jeong, Young-Gi;Yoon, Seung-Chae;Hong, Sun-Ig;Hong, Soon-Hyung;Kim, Hyoung-Seop
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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    • pp.980-981
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    • 2006
  • In this study, bottom-up type powder processing and top-down type SPD (severe plastic deformation) approaches were combined in order to achieve full density of Carbon nanotube (CNT)/metal matrix composites with superior mechanical properties by improved particle bonding and least grain growth, which were considered as a bottle neck of the bottom-up method using the conventional powder metallurgy of compaction and sintering. ECAP (equal channel angular pressing), the most promising method in SPD, was used for the CNT/Cu powder consolidation. The powder ECAP processing with 1, 2, 4 and 8 route C passes was conducted at room temperature.

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가정용 분산전원시스템의 성능 모사를 위한 전력부하 프로파일 예측 (Prediction of Electrical Load Profile for Use in Simulating the Performance of Residential Distributed Generation Systems)

  • 이상봉;조우진;이관수
    • 설비공학논문집
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    • 제23권4호
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    • pp.265-272
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    • 2011
  • The electrical load profiles of end-users must be analysed properly to introduce distributed generation system efficiently. In this study, numerical simulation for predicting a residential electrical load profile was developed to satisfy categorized electricity consumption range. We applied bottom-up approach to compose electrical load profile by using data from official reports and statistics. The electrical load profile produced from the simulation predicted peak times of public report accurately and agreed well with the standard residential electrical load profile of official reports within average error of 16.2%.

농촌개발사업 참여 주체의 역량 강화 방안 (Strategies and measures for capacity building in rural development project)

  • 김정섭;권인혜
    • 농촌지도와개발
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    • 제17권3호
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    • pp.385-418
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    • 2010
  • This study aimed to find the way to help participants build capacity in rural development projects, through some case studies and Q-methodology. Decentralization and diffusion of bottom-up approach in rural development projects are the main contextual factors in this study. With the ethos of bottom-up approach in rural development, the human and financial inputs for capacity building increased drastically in the area of rural development policy. Four types of capacity building methods were identified in this study; training, consulting, learning organization, and forum. Theses methods were used more at planning step than implementation step in rural development projects. The government's effort to strengthen leadership in rural areas should be continued. The existing government's training program for capacity building had better include more diverse clients. Actions for capacity building should be centered on the needs of the participants in fields. Especially, organizing learning units is very important. Governments' rural development policy should establish the proper process which can help local actors plan their projects with enough time span.

ECC 기능을 갖춘 IEEE-796 버스용 메모리 시스템 설계에 관한 연구 (The Study on a Main Memory System with ECC Capability Based on IEEE-796 Bus)

  • 박병권;방성영
    • 대한전자공학회논문지
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    • 제20권6호
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    • pp.29-32
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    • 1983
  • 본 논문은 작년도 국책 과제의 하나인 "16 bit 따이크로컴퓨터 개발"에서 개발친 16bit 마이 크로컴퓨터를 위한 주기억 시스템 개발에 관하여 기술한다. 이 주기억 시스템은 ECC 기능을 갖고 있으au IEEE-796 bus를 이용했다. 설계과정에서는 top-down 방식을 따랐으며 시험과정에 bottom-up 방식을 따랐다. 이렇게 해서 개발된 기억 보오드는 미국에서 시판되고 있는 것보다도 좋은 성능을 발휘했으며 가격도 저렴하다.

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영국의 통신망비용 산정모형 분석 (Analysis on the Network Costing Model in U.K.)

  • 권수천
    • 전자통신동향분석
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    • 제15권6호통권66호
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    • pp.150-159
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    • 2000
  • 본 논문은 영국의 통신망비용모형을 분석하고 있다. 영국은 1997년 10월부터 가격상한규제방식인 새로운 접속료규제제도를 도입하여 현재 적용해 오고 있다. 이 접속료규제제도는 기본적으로 장기증분비용에 근거한 접속료산정방식으로서 Top-down 방식에 의한 비용모형과 Bottom-up 방식에 의한 비용모형을 절충한 혼합모형을 적용하여 장기증분비용을 산정한 후, 이에 가격상한규제공식을 적용하는 방식이다. 본 논문에서는 우선 영국의 통신망비용모형 개발의 배경으로서 최근의 접속료산정방식의 변화상을 살펴보고 이어 BT가 제시한 Top-down 방식과 ICWG가 개발한 Bottom-up 방식을 각각 분석한 후 이들의 장.단점을 비교 검토하고 우리나라에의 시사점을 제시하고 있다.

급속응고 Al-20 wt% Si 합금 분말의 ECAP를 통한 고형화 (Consolidation of Rapidly Solidified Al-20 wt% Si Alloy Powders Using Equal Channel Angular Pressing)

  • 윤승채;홍순직;서민홍;정영기;김형섭
    • 한국분말재료학회지
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    • 제11권3호
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    • pp.233-241
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    • 2004
  • In this study, bottom-up type powder processing and top-down type SPD (severe plastic deformation) approaches were combined in order to achieve both full density and grain refinement of Al-20 wt% Si powders without grain growth, which was considered as a bottle neck of the bottom-up method using the conventional powder metallurgy of compaction and sintering. ECAP (Equal channel angular pressing), one of the most promising method in SPD, was used for the powder consolidation. The powder ECAP processing with 1, 2, 4 and 8 passes was conducted for 10$0^{\circ}C$ and 20$0^{\circ}C$ It was found by microhardness, compression tests and micro-structure characterization that high mechanical strength could be achieved effectively as a result of the well bonded powder contact surface during ECAP process. The SPD processing of powders is a viable method to achieve both fully density and nanostructured materials.