• 제목/요약/키워드: Technical approaches

검색결과 433건 처리시간 0.028초

빌딩 마이크로그리드가 포함된 새로운 빌딩에너지 시스템 구축방향에 관한 연구 (The Novel Configuration for Building Energy System Including Build ins Microgrid)

  • 홍원표
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2008년도 추계학술대회 논문집
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    • pp.235-240
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    • 2008
  • The recent development of efficient thermal prime movers for distributed generation id changing the focus of the production of electricity from large centralized power plants to local generation units scattered over the territory. The scientific communality is addressing the analysis and planning of the distributed energy resources(der) with wide spread approaches, taking into account technical, environmental, economical and social issues. The coupling of cogeneration system to absorption/electric chillers or heat pumps as well as the interactions with renewable sources, allow for setting up multi-generation systems for building cooling heating and power(BCHP) systems of different energy vectors such as electricity, heat(at different enthalpy levels), cooling power, hydrogen, various chemical substances and so forth. Adoption of the composite multi-generation systems may lead to significant benefits in term of higher efficiency, reduced $CO_2$ emissions and enhanced economy. This paper outlines the main aspects of the BCHP system framework, illistrating its characteristics and summarizing the relevant distributed multi-generation structures.

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접촉각 측정에 의한 RDX/EVA의 표면 에너지 해석 (The Analysis of surface free energy of RDX/EVA from contact angle measurements)

  • 심정섭;김현수;이근득
    • 한국군사과학기술학회지
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    • 제3권2호
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    • pp.219-230
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    • 2000
  • Plastic bonded explosive(PBX) is mainly composed of the nitramine explosives, RDX, HMX, and polymer binders. When the adhesion between nitramine crystals and binder is not particularly strong and can be failed under stress, dewetting occurs rather suddenly and this leads to a significant drop in tensile strength of explosives. Mechnical property of plastic bonded explosive depends on the surface characteristics of filler and binder. In order to design for better adhesion, an understanding of the surface properties of explosive and binder is essential. In this study, 2 kinds of RDX and 4 kinds of ethylene vinyl acetate copolymers are selected, since they are widely used in many plastic bonded explosives. The technical objective of this investigation is to calculate for the surface free energy of RDX and EVA using theory of Fowkes, van Oss, Neumann approaches and Kaelble equation and to predict the interaction between filler and binder from their surface free energies.

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A Cultural Dimensions Model based on Smart Phone Applications

  • Oh, Jung-Min;Moon, Nam-Mee
    • Journal of Information Processing Systems
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    • 제7권1호
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    • pp.209-220
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    • 2011
  • One of the major factors influencing the phenomenal growth of the smart phone market is the active development applications based on open environments. Despite difficulties in finding and downloading applications due to the small screens and inconvenient interfaces of smart phones, users download applications nearly every day. Such user behavior patterns indicate the significance of smart phone applications. So far, studies on applications have focused mainly on technical approaches, including recommendation systems. Meanwhile, the issue of culture, as an aspect of user characteristics regarding smart phone use, remains largely unexamined throughout the world. Hence, the present study attempts to analyze the highest ranked smart phone applications downloaded and paid for that are ranked the highest in 10 countries (Korea, Japan, China, India, the UK, USA, Indonesia, Canada, France, and Mexico) and we then derive the CDSC (Cultural Dimensions Score of Content) for these applications. The results derived are, then, mapped to the cultural dimensions model to determine the CISC (Cultural Index Score for Country). Further, culturally significant differences in smart phone environments are identified using MDS analysis.

A Review of Three Different Studies on Hidden Markov Models for Epigenetic Problems: A Computational Perspective

  • Lee, Kyung-Eun;Park, Hyun-Seok
    • Genomics & Informatics
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    • 제12권4호
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    • pp.145-150
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    • 2014
  • Recent technical advances, such as chromatin immunoprecipitation combined with DNA microarrays (ChIp-chip) and chromatin immunoprecipitation-sequencing (ChIP-seq), have generated large quantities of high-throughput data. Considering that epigenomic datasets are arranged over chromosomes, their analysis must account for spatial or temporal characteristics. In that sense, simple clustering or classification methodologies are inadequate for the analysis of multi-track ChIP-chip or ChIP-seq data. Approaches that are based on hidden Markov models (HMMs) can integrate dependencies between directly adjacent measurements in the genome. Here, we review three HMM-based studies that have contributed to epigenetic research, from a computational perspective. We also give a brief tutorial on HMM modelling-targeted at bioinformaticians who are new to the field.

전자상거래 신뢰서비스를 활성화시키기 위한 선진국들의 정책에 관한 비교 연구 (A Comparative Study on Policies Related To Trust Services in e-Business)

  • 이정우;이종성
    • 디지털융복합연구
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    • 제1권1호
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    • pp.213-234
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    • 2003
  • "Trust" becomes a focal issue in e-business. Unlike traditional business environment, virtual situation requires new trust-ensuring mechanism other than face-to-face meetings and other related means of confirmation. Many countries are trying to foster trust services industry in order to increase e-business transactions and activities. This paper compares and contrasts these countries' policies on trust services. Conclusions of this comparative research includes: (1) trust services industry will be tightly integrated horizontally and increase their scope vertically towards trust in business sense over and beyond the mere technical level trust, (2) necessity of reciprocal trust authentication exchange is calling for an international standard in a near future, and (3) two different types of policies are under development: government-led and industry-led. Advantages and disadvantages of different approaches are presented with details of legal implications and structures of operations.

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유연성 원리를 이용한 낙석방호시스템 (Flexible Barrier System for Rockfall Protection)

  • 최숭일;이창호;김덕봉
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2003년도 춘계학술대회 논문집
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    • pp.68-81
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    • 2003
  • Rockfall protection fence is one of the most common rockfall protection methods in Korea. If rockfall protection fences are required along the road or railway, their location, height and capacity, in terms of the maximum kinetic energy that they can absorb, should be specified. Within this paper, the best practice of rockfall barrier is introduced. Modern rockfall simulations as a means to define risks, protection requirements, dynamic loading and height of potential structures and selection of appropriate placement is presented. Technical possibilities of rockfall barriers and their actual limits are presented. Safety concepts based on probabilities approaches are proposed. Recent studies performed in other countries show that Flexible Barriers are also a feasible system to stop and retain debris flows. Finally an outlook onto further development is given.

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대 용량 메모리 기술 및 동향 (High Density Memory Technology and Trend)

  • 윤홍일;김창현;황창규
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 하계학술대회 논문집
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    • pp.17-20
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    • 2000
  • Over the years of decades, the memory technology has progressed a long, marble way. As we have evidenced from the Intel’s 1Kb DRAM in 1970 to the Gigabit era of 2000’s, the road further ahead towards the Terabit era will be unfolded. The technology once perceived inconceivable is in realization today, and similarly roadblocks as we know of today may become trivial issues for tomorrow. For the inquiring mind, the question is how the “puzzle” of tomorrow’s memory technology is pieced-in today. The process will take place both in evolutionary and revolutionary ways. Among these, note-worthy are the changes in DRAM architecture and the cell process technology. In this paper, some technical approaches will be discussed to bring these aspects into a general overview and a perspective with possibilities for the new memory technology will be presented.

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Laparoscopic Whipple's Operation for Locally Advanced Gastric Cancer Invading the Pancreas and Duodenum: a Case Report

  • Lee, Chang Min;Yoon, Sam-Youl;Park, Sungsoo;Park, Seong-Heum
    • Journal of Gastric Cancer
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    • 제19권4호
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    • pp.484-492
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    • 2019
  • Few surgeons have adopted pancreaticoduodenectomy (PD) for the treatment of advanced gastric cancer (AGC) invading the pancreas or duodenum because it remains controversial whether its prognostic benefits outweigh the high morbidity rates in such advanced cases. However, recent technical advances have revived diverse surgical procedures in minimally invasive approaches. Inspired by this trend, laparoscopic PD procedures have been performed for AGC in our institute since 2014. We recently performed a laparoscopic Whipple's operation in a case of cT4b gastric cancer with invasion of the pancreatic head and duodenum.

양자 기계학습 기술의 현황 및 전망 (The Present and Perspective of Quantum Machine Learning)

  • 정원주;이성환
    • 정보과학회 논문지
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    • 제43권7호
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    • pp.751-762
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    • 2016
  • 본고에서는 양자역학 기반의 기계학습인 양자 기계학습의 현황과 전망을 조망하고자 한다. 양자역학 기반의 양자컴퓨팅이 보여준 혁신적인 계산속도 개선에 힘입어 기계학습 분야에 양자컴퓨팅 알고리즘을 적용하는 연구는 빅데이터 시대의 도래에 따라 최근 집중적인 관심을 받고 있다. 고전적인 기계학습 알고리즘들에 양자컴퓨팅을 접목하여 획기적인 속도개선을 가능하게 하는 알고리즘 연구들과 최초의 상용 양자컴퓨터로 화제가 되고 있는 양자 담금질 알고리즘 등을 중심으로 양자 기계학습의 최신동향과 가능성을 살펴보고자 한다.

Several Problems in Reactor Coolant System Flow Rate Measurement

  • Ahn, Seung-Hoon;Auh, Geun-Sun;Suh, nam-Cuk;Park, Jun-Sang;Koo, Bon-Hyun
    • Nuclear Engineering and Technology
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    • 제30권6호
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    • pp.592-608
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    • 1998
  • Inspection of RCS flow measurements for the domestic pressurized water reactors has been performed by the Korea Institute of Nuclear Safety (KINS) as one of the authorized periodical inspection activities. The inspection results for the Westinghouse-type plants reveal that 1) the RCS flow instrumentation has been calibrated by using the initial design and commissioning test result, without reflecting the cycle specific reference flow measurements, 2) the loop-to-loop now variation in the actual flow measurement which has not been considered in the safety analysis affects the asymmetric How transient results, and 3) the measured RCS flows in Kori 3 and 4, Yonggwang 1 and 2 do not support the definition of the best estimate RCS flow, approaching the RCS flow limit. In this study, the revealed problems were discussed with review of the design and the RCS flow measurement uncertainty evaluation, and the technical approaches and recommendations for resolving these problems were proposed.

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