• Title/Summary/Keyword: 점유영역

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Adaptive Power Control based Efficient Localization Technique in Mobile Wireless Sensor Networks (모바일 무선 센서 네트워크에서 적응적 파워 조절 기반 효율적인 위치인식 기법)

  • Lee, Joa-Hyoung;Jung, In-Bum
    • The KIPS Transactions:PartC
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    • v.16C no.6
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    • pp.737-746
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    • 2009
  • Given the increased interest in ubiquitous computing, wireless sensor network has been researched widely. The localization service which provides the location information of mobile user, is one of important service provided by sensor network. Many methods to obtain the location information of mobile user have been proposed. However, these methods were developed for only one mobile user so that it is hard to extend for multiple mobile users. If multiple mobile users start the localization process concurrently, there could be interference of beacon or ultrasound that each mobile user transmits. In the paper, we propose APL(Adaptive Power Control based Resource Allocation Technique for Efficient Localization Technique), the localization technique for multiple mobile nodes based on adaptive power control in mobile wireless sensor networks. In APL, collision of localization between sensor nodes is prevented by forcing the mobile node to get the permission of localization from anchor nodes. For this, we use RTS(Ready To Send) packet type for localization initiation by mobile node and CTS(Clear To Send) packet type for localization grant by anchor node. NTS(Not To Send) packet type is used to reject localization by anchor node for interference avoidance and STS(Start To Send) for synchronization between 모anchor nodes. At last, the power level of sensor node is controled adaptively to minimize the affected area. The experimental result shows that the number of interference between nodes are increased in proportion to the number of mobile nodes and APL provides efficient localization.

耐 마모 코우팅 생산을 위한 CVD와 PVD 기술

  • O, Seung-Tak
    • Journal of the Korean institute of surface engineering
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    • v.20 no.1
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    • pp.15-24
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    • 1987
  • 超硬合金과 高速度鋼에 TiC, TiN 그리고 $Al_2O_3$의 耐 마모 코우팅시에 사용되는 CVD와 PVD 기술을 M E Sjostrand와 A G Thelin 등이 본 논문에서 논의하였다. 또한 CVD와 PVD 의 특별한 장점과 응용영역에 대하여도 토의하였다. 수년동안 CVD 기술은 금속질화물, 금속탄화물 그리고 금속산화물 등의 耐 마모 코우팅을 생산하는데 성공적으로 사용되어 왔다. Munster와 Ruppert에서는 1950년대 초기에 TiC와 TiN의 CVD 공정을 연구했는데 이런 코우팅 재료의 높은 화학적 안정성과 더불어 高硬鋼라는 독특한 성질로 인해 그 주요 영역이 명백해졌다. 1968년에 처음으로 CVD법에 의한 보호막 코우팅의 대규모 응용이 이루어졌는데 그것은 超硬合金 절삭공구의 코우팅이었다. (그림1 참고) 이것은 硬금속산업에 있어서 가장 중요한 발전단계였다. TiC, TiN 그리고 $Al_2O_3$로 코우팅된 공구의 생산은 1970년대에 빠른 성장을 보였으며 오늘날 사용되는 절삭날의 50% 이상을 점유하고 있다. (그림2 참고) TiC와 TiN은 현재 이용되고 있는 모든 耐 마모 코우팅 중에서 독보적인 위치를 차지하고 있다. 그 이유는 생산과정이 비교적 단순하기 때문이다. 지난 5년동안 절삭공구와 總形바이트의 코우팅에 대한 PVD기술의 응용이 폭발적으로 증가했다. 증착기술인 이들 CVD와 PVD 각각은 자체의 독특한 장점이 있으므로 그 응용영역은 증착조건, 즉 기지금속의 접착성과 증착온도 그리고 증착속도등에 따라 매우 다를 것이다. PVD 공정으로 인해 고속도 공구강이 급속도로 발전되었고 더우기 PVD공정은 500$^{\circ}C$ 이하의 증착온도에서 brazed carbide 공구의 코우팅을 가능하게 하였다. 따라서 두 증착기술은 서로 상반적이라기 보다는 상호보완적인 것이라고 생각하는 편이 더 좋다.TEMPLA에 비해 CLB의 수가 15.58% 감소되었다. 높은 활성을 나타내었다. 정제된 효소의 최적온도는 40$^{\circ}C$이었으며 20~50$^{\circ}C$에서 비슷한 활성을 나타내었고, 30$^{\circ}C$에서는 60분동안 효소활성이 거의 상실되지 않았다. 정제된 효소는 ethanol과 chloroform 처리에는 안정하였으나 12mM AT 와 0.1mM $NaN_3$ 및 1mM KCN에 의해 90% 이상의 활성이 억제되었다.이에 근거하여 서울시 학생들($7{\sim}18$세)의 만성신부전증 유병률은 1백만명당 5.7명으로 추정되었다. 결론 : 서울시내 학생들 중 11세, 14세, 17세 3개 군에서 한 번 검사로 확인된 무증상 단백뇨의 유병률은 0.28%(약 2.8명/1,000명)이었고 이들중 약 5%만이 3차검사에서 신질환이 의심되었으며 이에 따른 신질환 유병률은 1만명당 1.4명이었다. $7{\sim}18$세 연령층에서 무증상으로 발생하는 사구체 신질환 중에는 IgA 신병증의 유병률이 가장 높아 1만명당 0.64명으로 추정되었고 만성신부전증의 유병률은 1백만명당 5.7명으로 추정되었다. 집단뇨 검사를 통해 확인되는 신질환은 대부분 사구체 질환이기 때문에 집단뇨검사의 의의는 좀더 연구가 필요할 것으로 생각되었다. 오히려 증상을 동반하는 경우보다 빈도가 증가한다는 사실은 집단뇨 검사에서 소변의 이상소견이 발견되어 신장 조직검사를 실시할 경우 혈청 $C_3$치의 감소 여부에 관계없이 MPGN도 진단적 고려 대상이 되어야 한다고 생각한다.신장 조직검사를 시행한 결과 진행성 경과를 취할 수 있는 막 증식성 사구체 신염과 매우 희귀한 증례인 신유전분증 등으로 진단됨으로써 지속성 단백뇨의 경우 정확 진단적 접근이 필수적임을 알 수 있다. 기립성

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A Comparative Study between Space Law and the Law of the Sea (우주법과 해양법의 비교 연구)

  • Kim, Han-Taek
    • The Korean Journal of Air & Space Law and Policy
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    • v.24 no.2
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    • pp.187-210
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    • 2009
  • Space law(or outer space law) and the law of the sea are branches of international law dealing with activities in geographical ares which do not or do only in part come under national sovereignty. Legal rules pertaining to the outer space and sea began to develop once activities emerged in those areas: amongst others, activities dealing with transportation, research, exploration, defense and exploitation. Naturally the law of the sea developed first, followed, early in the twentieth century, by air law, and later in the century by space law. Obviously the law of the sea, of the air and of outer space influence each other. Ideas have been borrowed from one field and applied to another. This article examines some analogies and differences between the outer space law and the law of the sea, especially from the perspective of the legal status, the exploration and exploitation of the natural resources and environment. As far as the comparisons of the legal status between the outer space and high seas are concerned the two areas are res extra commercium. The latter is res extra commercium based on both the customary international law and treaty, however, the former is different respectively according to the customary law and treaty. Under international customary law, whilst outer space constitutes res extra commercium, celestial bodies are res nullius. However as among contracting States of the 1967 Outer Space Treaty, both outer space and celestial bodies are declared res extra commercium. As for the comparisons of the exploration and exploitation of natural resources between the Moon including other celestial bodies in 1979 Moon Agreement and the deep sea bed in the 1982 United Nations Convention on the Law of the Sea, the both areas are the common heritage of mankind. The latter gives us very systematic models such as International Sea-bed Authority, however, the international regime for the former will be established as the exploitation of the natural resources of the celestial bodies other than the Earth is about to become feasible. Thus Moon Agreement could not impose a moratorium, but would merely permit orderly attempts to establish that such exploitation was in fact feasible and practicable, by allowing experimental beginnings and thereafter pilot operations. As Professor Carl Christol said until the parties of the Moon Agreement were able to put into operation the legal regime for the equitable sharing of benefits, they would remain free to disregard the Common Heritage of Mankind principle. Parties to one or both of the agreements would retain jurisdiction over national space activities. In so far as the comparisons of the protection of the environment between the outer space and sea is concerned the legal instruments for the latter are more systematically developed than the former. In the case of the former there are growing tendencies of concerning the environmental threats arising from space activities these days. There is no separate legal instrument to deal with those problems.

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Scientific and technological activities for development and Gijutsushi -Technological Transfer- (선단기술과 기술사)

  • 일본명
    • Proceedings of the Korean Professional Engineer Association Conference
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    • 1986.03a
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    • pp.60-65
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    • 1986
  • Today scientific and technological activities for development raise a whole series of problems with the institutionalization and the professionalization of science, but also with the increasingly obvious links between technologies, innovation and production of goods and services, and the difficulties caused by relationship between sovereign one. Solving these problems therefore requires discussion, agreements, and consensus, not only with the Korean Government, where present budget difficulties demand trad-offs between scientific and technological activities and other forms of technical assistance on the one hand, and other R&D objectives on the other. The purpose of this paper is to examine the problems facing auther's own experiences in this connection and to show what kinds of solutions they have been applying in order to identify some useful inputs through consulting engineer for discussion. It is based on very general accounts of the policies, institutions and activities of about own experiences and, even for those, only on rather limited, fragmentary information derived from the few official documents.

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Business Records and Information Management as Preparation for e-Discovery Risks (전자증거개시상의 위험에 대응한 기업기록정보관리 방안)

  • Seol, Moon-won;Lee, Haein
    • Journal of Korean Society of Archives and Records Management
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    • v.16 no.4
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    • pp.7-30
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    • 2016
  • The purpose of this study is to suggest the directions for record and information management (RIM) strategies for Korean companies as preparation for e-Discovery risks. It begins with the articulation key concepts and some RIM issues of e-Discovery, which is governed by the U.S. Federal Rules of Civil Procedures. It analyzes three lawsuit cases for which Korean companies were sued by North American companies in order to determine the main reasons behind the defensible disposition failures. Based on the analyses, it suggests the RIM strategic policies for preparing the e-Discovery, including the development of inventories for documents and ESI in their possession, custody, or control; ensuring legal hold programs in good faith; and making defensible retention policies.

A Deadlock A voidance Method and a Regression-Based Route Selection Scheme for AGV s in Automated Container Terminals (자동화 컨테이너 터미널에서 AGV 교착 방지와 회귀 분석을 이용한 경로 선정 방안)

  • Jun Jin-Pyo;Ryu Kwang-Ryel;Yoon Hang-Mook
    • Journal of Navigation and Port Research
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    • v.29 no.8 s.104
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    • pp.723-733
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    • 2005
  • This paper presents a deadlock avoidance method for AGVs in automated container terminals. For a more efficient use of AGV traveling area, we divided the area into small-sized grids not enough to cover a whole AGV. Our deadlock avoidance method controls AGVs by identifying strongly connected components(SCCs) in a graph derived from the paths of AGVs on the grids. Also in this paper we suggest a route selection scheme which selects a route by predicting and comparing travel times of candidate routes by using a regression formula. Simulation experiments have shown that the proposed method can control AGVs for 48 hours without deadlocks and the count of AGV visits per QC is increased by $2\~10$ an hour.

Vegetation Structure of Secheon Valley Area and Forest Vegetation Types in Mt. Sikjang (식장산 산림식생유형과 세천계곡부의 식생구조)

  • Hwang, Seon-Mi;Yun, Chung-Weon
    • Korean Journal of Environmental Biology
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    • v.25 no.3
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    • pp.249-259
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    • 2007
  • This study was carried out the analysis of forest vegetation structure using the phytosociological methods by Braun-Blanquet from April to November in 2006. The results were summarized as follows. The forest vegetation was classified into 23 communities and 3 forest ecosystem types such as slope forest type, valley forest type and artificial forest type. By the actual vegetation map, Quercus mongolica forest was widely distributed in the area and Pinus densiflora forest and Quercus variabilis forest in the southern parts of the slope and valley forest mainly in valley area, respectively. The importance value in the Q. mongolica forest and artificial forest was absolutely high for the species dominated in tree layer. The typical valley species of Lindera erythrocarpa and Styrax japonica were abundantly occupied in the all layers. Species diversity indices of Alnus hirsta forest was the lowest as 0.2191, and that of valley forest was about 0.9, the highest among the all forest types.

Study on Technologies of Mobile Communication based Train Control and its Radio Communication Requirements (이동통신기반 열차제어 기술과 무선통신 요구사항 연구)

  • Yoon, Byungsik;Choi, Minsuk;Kim, Dong Joon;Oh, Woo-Sik;Sung, Dong-Il
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2018.10a
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    • pp.457-460
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    • 2018
  • The mobile communication based train control is the train control system by utilizing wireless communication rather than conventional wired communication. Traditional train control operates train occupation, safety integrity and moving authority using fixed block wired railway signal system. Since introduction of mobile communication in railway area, railway operators can provide improved passager services. Futhermore, it can replace inefficient train onboard equipments and railway ground facilities for economic benefits. In this paper we introduce mobile communication based railway system currently in operation around the world. Moreover, we provide the minimum requirements of the radio communication performance. Proposed minimum requirements of the radio communication improve more secure and efficient mobile communication based train control system.

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The Management Strategies of TSR Service Operators in Korea (우리나라 TSR Service Operators의 발전 방향에 관한 연구)

  • Jang, Dong-Jin;Shin, Han-Won;Shin, Young-Ran
    • Journal of Korea Port Economic Association
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    • v.27 no.4
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    • pp.145-164
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    • 2011
  • The Northeast Asia has been the fastest growing region in the world for the past few decades. And now the economic bloc maintains its status as a major powerhouse of the world economy. On the way of its economic growth, Russia and Central Asian countries have emerged as major trading partners. The Trans-Siberian Railway(TSR) has been playing a pivotal role in promoting economic cooperation between the two regions. This paper investigates economic environment of the Korean TSR service operators through the SWOT analysis, then proposes management strategies for them. For this purpose, the authors analyze characteristics and roles of the TSR service operators. In addition, a comparison of difference between service operators and shippers about their recognition of economic environment of the TSR transportation service is also carried out.

Research on the public education goal of design (디자인 대중교육의 지향점에 관한 연구)

  • Cho, kyu-myung
    • Proceedings of the Korea Contents Association Conference
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    • 2008.05a
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    • pp.743-748
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    • 2008
  • Design is objective and universal human aesthetic activity. Design originally began with the purpose 'to make public's life abundant and increase their quality of living." However, design education has bee developed to foster human resource to maximize production of company in the name of 'important production method for company.' Therefore, common people has been had many opportunities to learn about design. General people could not be satisfied their demand to learn about design due to narrow opportunities. Public has had resistance feeling for design that it has been exclusively occupied by certain designers. Therefore, it is urgent to expand the object of design education and change the contents which have been focused on fostering design professionals. This research examined about the goal of public design education (self-expression, enjoying quality of life, culture, and wisdom of living) as a way to increase our life quality by recognizing the need of public design education based on various social phenomena which strongly shows people's desire to pursue aesthetic life.

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