• 제목/요약/키워드: local-global principle

검색결과 41건 처리시간 0.026초

원추형 코일스프링의 강성에 대한 연구 (A Study on the Stiffness of Frustum-shaped Coil Spring)

  • 김진훈;이수종;이경호
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2001년도 추계학술대회 논문집(Proceeding of the KOSME 2001 Autumn Annual Meeting)
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    • pp.21-27
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    • 2001
  • Springs are widely utilized in machine element. To find out stiffness of frustum-shaped coil spring, the space beam theory using the finite element method is adopted in this paper In three dimensional space, a space frame element is a straight bar of uniform cross section which is capable of resisting axial forces, bending moments about two principal axes in the plane of its cross section and twisting moment about its centroidal axis. The corresponding displacement degrees of freedom are twelve. To find out load vector of coil spring subjected to distributed compression, principle of virtual work is adapted The displacements of nodal points due to small increment of force are calculated by the finite element method and the calculated nodal displacements are added to coordinates of nodal points. The new stiffness matrix of the system using the new coordinates of nodal points is adopted to calculate the another increments of nodal displacements, that is, the step by step method is used in this paper. The results of the finite element method are fairly well agreed with those of various experiments. Using MATLAB program developed in this paper, spring constants and stresses can be predicted by input of few factors.

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산업안전보건 분야의 UN 국제적 화학물질관리에 대한 전략적 접근(SAICM) 이행에 관한 연구 (A study on the implementation of UN SAICM in the occupational safety and health)

  • 이권섭;이혜진;이종한;양정선
    • 한국산업보건학회지
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    • 제20권4호
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    • pp.282-294
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    • 2010
  • The purpose of SAICM (Strategic Approach to International Chemicals Management) is to minimize the health and environmental hazards from the production and the consumption of chemicals by improving the chemicals management capability of developing countries and implementing a system of the risk assessment and the management based on the precautionary principle until 2020. To achieve this purpose, the UN has prescribed the principles, objectives and establishment of an action plan for the chemicals management strategy which must be carried out at international, local, and national levels, and requested the implementation of the Global Plan of Action (GPA) comprising of 273 recommendations in 36 work areas. SAICM is currently based on voluntary participation, but is expected to become the basic framework of international order in relation to chemicals management in the future. This study aims to analyze the practice in the occupational safety and health area relating to implement 273 recommendations of the GPA, and propose complementary measures for the system in order to provide political advices for establishing future plans to manage industrial chemicals. Twenty three areas of total 36 work areas and 161 items of 273 recommendations have relevance to occupational safety and health areas. We have found that, as a national implementation level, 157 of 161 industrial safety and health items are being implemented at a satisfactory level in regard to the implementation of the GPA, while 4 items, including the ratification of the ILO Conventions 170, 174, 184, and support for GHS (Globally Harmonized System of Classification and Labeling of chemicals) implementation of developing countries, require additional complementary measures for the system and operation.

Inter-Domain Mobility Management Based on the Proxy Mobile IP in Mobile Networks

  • Gohar, Moneeb;Koh, Seok-Joo
    • Journal of Information Processing Systems
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    • 제12권2호
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    • pp.196-213
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    • 2016
  • System Architecture Evolution (SAE) with Long Term Evolution (LTE) has been used as the key technology for the next generation mobile networks. To support mobility in the LTE/SAE-based mobile networks, the Proxy Mobile IPv6 (PMIP), in which the Mobile Access Gateway (MAG) of the PMIP is deployed at the Serving Gateway (S-GW) of LTE/SAE and the Local Mobility Anchor (LMA) of PMIP is employed at the PDN Gateway (P-GW) of LTE/SAE, is being considered. In the meantime, the Host Identity Protocol (HIP) and the Locator Identifier Separation Protocol (LISP) have recently been proposed with the identifier-locator separation principle, and they can be used for mobility management over the global-scale networks. In this paper, we discuss how to provide the inter-domain mobility management over PMIP-based LTE/SAE networks by investigating three possible scenarios: mobile IP with PMIP (denoted by MIP-PMIP-LTE/SAE), HIP with PMIP (denoted by HIP-PMIP-LTE/SAE), and LISP with PMIP (denoted by LISP-PMIP-LTE/SAE). For performance analysis of the candidate inter-domain mobility management schemes, we analyzed the traffic overhead at a central agent and the total transmission delay required for control and data packet delivery. From the numerical results, we can see that HIP-PMIP-LTE/SAE and LISP-PMIP-LTE/SAE are preferred to MIP-PMIP-LTE/SAE in terms of traffic overhead; whereas, LISP-PMIP-LTE/SAE is preferred to HIP-PMIP-LTE/SAE and MIP-PMIP-LTE/SAE in the viewpoint of total transmission delay.

Evolutionary Optimization of Pulp Digester Process Using D-optimal DOE and RSM

  • Chu, Young-Hwan;Chonghun Han
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.395-395
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    • 2000
  • Optimization of existing processes becomes more important than the past as environmental problems and concerns about energy savings stand out. When we can model a process mathematically, we can easily optimize it by using the model as constraints. However, modeling is very difficult for most chemical processes as they include numerous units together with their correlation and we can hardly obtain parameters. Therefore, optimization that is based on the process models is, in turn, hard to perform. Especially, f3r unknown processes, such as bioprocess or microelectronics materials process, optimization using mathematical model (first principle model) is nearly impossible, as we cannot understand the inside mechanism. Consequently, we propose a few optimization method using empirical model evolutionarily instead of mathematical model. In this method, firstly, designing experiments is executed fur removing unecessary experiments. D-optimal DOE is the most developed one among DOEs. It calculates design points so as to minimize the parameters variances of empirical model. Experiments must be performed in order to see the causation between input variables and output variables as only correlation structure can be detected in historical data. And then, using data generated by experiments, empirical model, i.e. response surface is built by PLS or MLR. Now, as process model is constructed, it is used as objective function for optimization. As the optimum point is a local one. above procedures are repeated while moving to a new experiment region fur finding the global optimum point. As a result of application to the pulp digester benchmark model, kappa number that is an indication fur impurity contents decreased to very low value, 3.0394 from 29.7091. From the result, we can see that the proposed methodology has sufficient good performance fur optimization, and is also applicable to real processes.

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공정무역에서 생산자의 하위주체성 극복과 생산자 주도 지역 발전 (The Overcome of Subalternity for the Producers of Fair Trade and the Ways for Producer-led Regional Development)

  • 이용균
    • 한국지역지리학회지
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    • 제23권1호
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    • pp.47-61
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    • 2017
  • 최근 개도국의 빈곤을 해소하기 위한 국제사회의 관심이 고조되고 있다. 공정무역은 공정한 거래를 통해 개도국의 빈곤을 해소하기 위한 실천으로 주목을 받았다. 본 연구는 공정무역이 개도국의 발전에 긍정적 효과를 가져오지 못한 점에 주목하여, 공정무역의 문제를 생산자의 하위주체성이란 맥락에서 고찰한다. 공정무역은 선진국과 개도국 간 파트너 관계를 강조한 공정성의 원리에 기초하여, 개도국의 지속가능한 발전을 지향하는 사회운동이었다. 하지만, 공정무역은 개도국의 가난을 극복할 수 있는 바람직한 실천이 아님이 밝혀지고 있다. 본 연구는 공정무역이 공정한 거래가 되지 못하는 이유를 선진국이 주도하는 원조성 프로그램의 일환으로 추진되었기 때문임을 밝히면서, 개도국의 생산자가 중심이 되는 공정무역의 실천을 제시한다. 이를 위해 개도국의 로컬은 개발에 대한 인식적 전환, 시장의 가치에 대한 재발견, 자유로서의 발전, 로컬의 개별성을 고려한 발전 방향을 포스트개발의 맥락에서 고려할 필요가 있다.

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사립대학의 구조조정을 둘러싼 쟁점과 합리적 해결 방안 (Issues and Solutions of Restructuring Private Universities)

  • 최호성
    • 수산해양교육연구
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    • 제24권6호
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    • pp.901-919
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    • 2012
  • The purpose of this study is to conceptualize some issues around university restructuring in Korea, and explore rational-practical solutions ensuring the survival of higher education institutes confronting many challenges like rapid decreasing rate of birth, global open market of higher education system, and the phenomena of concentration on capital city area etc.. In order to achieve study goals, higher education policies and provisions of past governments from DaeJung Kim's to current MeongBak Lee's were analyzed, and also characteristics and directions of university restructuring of each government were identified. Through this analysis, it was evident that the main concern of university restucturing discourse was primarily focused on how to make public universities have high level of competitiveness. On the other hand, private universities had been totally alienated from university restructuring discourse since 1990's, despite their historical and great contributions to national development of our country. Based on some criticisms of educational policies of national government and partial revision proposal of the higher education act initiated by a few assemblymen, this study suggested eight solutions for developmental restructuring of private universities; constructing comprehensive framework of university restructuring, keeping market-friendly restructuring principle to allow universities take an autonomous position, revising methods, criteria and indexes of university evaluation, reducing the number of enrolling students, not the number of universities and colleges, a new policy to develop local universities allying with universities located at capital city area, differentiating private universities into two types of semi- or quasi-national university and complete autonomous university, legislating financial supports to private universities, and lastly, equal treatment of public and private universities in pursuit of half price tuition.

A CPU-GPU Hybrid System of Environment Perception and 3D Terrain Reconstruction for Unmanned Ground Vehicle

  • Song, Wei;Zou, Shuanghui;Tian, Yifei;Sun, Su;Fong, Simon;Cho, Kyungeun;Qiu, Lvyang
    • Journal of Information Processing Systems
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    • 제14권6호
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    • pp.1445-1456
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    • 2018
  • Environment perception and three-dimensional (3D) reconstruction tasks are used to provide unmanned ground vehicle (UGV) with driving awareness interfaces. The speed of obstacle segmentation and surrounding terrain reconstruction crucially influences decision making in UGVs. To increase the processing speed of environment information analysis, we develop a CPU-GPU hybrid system of automatic environment perception and 3D terrain reconstruction based on the integration of multiple sensors. The system consists of three functional modules, namely, multi-sensor data collection and pre-processing, environment perception, and 3D reconstruction. To integrate individual datasets collected from different sensors, the pre-processing function registers the sensed LiDAR (light detection and ranging) point clouds, video sequences, and motion information into a global terrain model after filtering redundant and noise data according to the redundancy removal principle. In the environment perception module, the registered discrete points are clustered into ground surface and individual objects by using a ground segmentation method and a connected component labeling algorithm. The estimated ground surface and non-ground objects indicate the terrain to be traversed and obstacles in the environment, thus creating driving awareness. The 3D reconstruction module calibrates the projection matrix between the mounted LiDAR and cameras to map the local point clouds onto the captured video images. Texture meshes and color particle models are used to reconstruct the ground surface and objects of the 3D terrain model, respectively. To accelerate the proposed system, we apply the GPU parallel computation method to implement the applied computer graphics and image processing algorithms in parallel.

Principle of restoration ecology reflected in the process creating the National Institute of Ecology

  • Kim, A. Reum;Lim, Bong Soon;Seol, Jaewon;Lee, Chang Seok
    • Journal of Ecology and Environment
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    • 제45권3호
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    • pp.105-116
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    • 2021
  • Background: The creation of the National Institute of Ecology began as a national alternative project to preserve mudflats instead of constructing the industrial complexes by reclamation, and achieve regional development. On the other hand, at the national level, the research institute for ecology was needed to cope with the worsening conditions for maintaining biodiversity due to accelerated climate change such as global warming and increased demand for development. In order to meet these needs, the National Institute of Ecology has the following objectives: (1) carries out studies for ecosystem change due to climate change and biodiversity conservation, (2) performs ecological education to the public through exhibition of various ecosystem models, and (3) promotes regional development through the ecological industry. Furthermore, to achieve these objectives, the National Institute of Ecology thoroughly followed the basic principles of ecology, especially restoration ecology, in the process of its construction. We introduce the principles and cases of ecological restoration applied in the process. Results: We minimized the impact on the ecosystem in order to harmonize with the surrounding environment in all the processes of construction. We pursued passive restoration following the principle of ecological restoration as a process of assisting the recovery of an ecosystem degraded for all the space except in land where artificial facilities were introduced. Reference information was applied thoroughly in the process of active restoration to create biome around the world, Korean peninsula forests, and wetland ecosystems. In order to realize true restoration, we pursued the ecological restoration in a landscape level as the follows. We moved the local road 6 and high-voltage power lines to underground to ensure ecological connectivity within the National Institute of Ecology campus. To enhance ecological diversity, we introduced perch poles and islands as well as floating leaved, emerged, wetland, and riparian plants in wetlands and mantle communities around the forests of the Korean Peninsula in the terrestrial ecosystem. Furthermore, in order to make the public aware of the importance of the intact nature, the low-lying landscape elements, which have disappeared due to excessive land use in most areas of Korea, was created by imitating demilitarized zone (DMZ) landscape that has these landscape elements. Conclusions: The National Institute of Ecology was created in an eco-friendly way by thoroughly reflecting the principles of ecology to suit its status and thus the impact on the existing ecosystem was minimized. This concept was also designed to be reflected in the process of operation. The results have become real, and a result of analysis on carbon budget analysis is approaching the carbon neutrality.

생태계적 방식에 의한 무형문화유산 체계 연구 - 자생력 강화방안을 중심으로 - (A Study on Improving Operating System of an Intangible Cultural Heritage by an Ecological Perspective)

  • 오정심
    • 헤리티지:역사와 과학
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    • 제48권3호
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    • pp.30-45
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    • 2015
  • 본 글의 목적은 사회적 수요의 부족 등으로 인한 국내 무형문화유산의 전승 단절 위기 현상을 주목하고, 문제의 해결방안 중 하나로 자생력 측면에서 무형문화유산 체계를 검토하여 그 발전방안을 모색하는 데 있다. 이러한 목적 하에 본 논문의 제2장에서는 연구방법론으로써 생태계적 방식을 고찰하고 생태계적 방식을 통해 무형문화유산 체계를 분석하였다. 생태계적 방식은 시스템의 운영에 생태계의 특징 및 원리를 적용하여 외부의 개입을 전제하거나 동원하지 않고서도 내부의 자생력만으로 시스템을 유지하는 것을 말한다. 그리고 무형문화유산 체계는 무형문화유산을 보호 전승 활용하기 위해 구성된 제도적 시스템을 말하며 크게 문화재보호법에 의한 기본원칙, 활동주체 그리고 절차 및 방법으로 나눠 살펴볼 수 있다. 생태계적 관점에서 검토한 결과 상호관계성, 순환성, 개방성, 다양성, 균형성 등과 관련한 문제점이 지적되며 정부의 개입을 전제하지 않으면 무형문화유산 체계가 제대로 운영될 수 없는 구조적 문제가 고착화되어 있다. 이에 제3장에서 생태계 원리를 적용해 무형문화유산의 체계의 개선 및 자생력 강화 방안을 제시하였다. 우선 유네스코 무형문화유산보호협약을 기초로 하여 상호관계성, 다양성, 균형성 등 생태계적 관점에 입각해 관련 규정의 기본원칙을 제시하였고, 전체론적 관점에서 제도의 구성요소 및 활동주체의 범위를 확대하여 제안하였다. 그리고 기존 활동주체의 역할 및 관계가 기 예능의 원형 보전에 치중했던 점을 개선하여 무형문화유산의 생산 소비 재생산 소멸 등 선순환적 발전의 흐름이 일어나도록 자연생태계의 생산자, 소비자, 분해자 개념에 따라 그 역할과 관계를 재편성하여 제안하였다. 기존의 체계와 비교하여 활동주체로 창작자, 프로슈머, 창업자, 시민 예술가 등을 제시하였는데 이들의 활동은 공급의 다양화에 기여할 수 있을 것이며 장기적으로 생태계가 건강하게 유지될 수 있는데 기여할 수 있을 것이다. 마지막으로 활동주체들 간의 자유로운 상호작용을 통해 사회의 수요와 공급의 조화, 순환적 발전의 흐름이 일어날 수 있도록 제도의 구성 및 운영 방향을 제시하였다.

다차원 안보위협과 융합 안보 (Multi-dimensional Security Threats and Holistic Security - Understanding of fusion-phenomenon of national security and criminal justice in post-modern society -)

  • 윤민우;김은영
    • 시큐리티연구
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    • 제31호
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    • pp.157-185
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    • 2012
  • 오늘날 사이버 공간의 도래와 일상화라는 증강 현실의 확대, 그리고 세계화로 인한 인간과 물품, 그리고 문화의 빠른 이동 등의 결과는 우리가 생산을 하고 경제활동을 하고 문화생활을 하는 일상의 혁명적인 변환뿐만 아니라 우리가 상대방을 공격하고 파괴하는 범죄나 전쟁 등의 폭력 사용에서의 혁명적인 변환을 가져왔다. 그리고 이러한 환경 조건의 변화는 개인적인 차원에서 지역적 차원, 그리고 국가적 차원과 지구적 차원에 걸쳐 다른 차원에서 각각 존재해 왔던 여러 다양한 차원의 안보 또는 치안의 위협들을 서로 결합시킴으로서 이러한 여러 다른 차원의 안보 또는 치안의 위협들을 다차원 안보위협의 총합이라는 형태로 오늘날 우리의 삶과 개개인의 안전과 국가적 단위에 심각한 위협이 되도록 조건지우고 있다. 이 논문은 이러한 다차원 안보위협의 총합이 서로 얽혀 있으며 각각의 개별 안보 위협들의 총합을 함께 바라보는 통합적 시각을 가질 때 문제의 근원적 실체를 제대로 이해할 수 있고 우리가 직면하고 있는 공포의 실체를 정확히 파악할 수 있음을 보여주고자 한다. 이 글에서 제시하는 개념인 융합안보라는 개념은 다차원 안보위협의 총합에 대한 통합적 네트워크적 응전의 방식을 개념적으로 제시한 것이다. 융합안보는 기존의 국가안보와 치안이라는 분절적 시각을 극복하고 국가안보와 치안을 통합적으로 인식하고 정보기관, 군, 경찰, 검찰, 소방, 민간 경비 등의 각 영역들의 경계를 넘어 통합적으로 접근함으로서 오늘날 다차원 안보위협이 던지고 있는 도전들에 대한 응전의 방식들을 만들어 가고자하는 개념적 노력이다. 그와 함께 이 논문은 융합안보와 관련하여 해외의 주요 국제기구와 국가들에서 시도되고 있는 통합적 네트워크적 대응 방안들에 대해서도 소개하고자 한다. 글쓴이는 지난 10년간 미국, 러시아, 이스라엘, 우즈베키스탄, 오스트리아, 캐나다, 멕시코, 독일 등지를 돌면서 관찰하였던 사항들과 여러 교육, 훈련과 세미나, 콘퍼런스, 그리고 개인적 접촉 등의 기회를 통해 가졌던 여러 관련 전문가들과의 인터뷰 등의 내용을 종합하여 유엔 등 국제기구와 세계의 여러 주요 국가들에서 시도되어오고 있는 오늘날의 보다 복잡한 안보위협들에 대한 융합적 대응방안들, 즉 기관의 네트워크적 협력, 데이터베이스의 구축 및 교류 등 을 소개할 것이다.

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