• Title/Summary/Keyword: 위상 연관성

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On vertical profiles of cohesive sediment: concentration, velocity gradient, and Stokes number (가는 유사 부유의 연직구조 특성 : 농도, 속도경사, 스토크스 수)

  • Son, Minwoo;Byun, Jisun
    • Proceedings of the Korea Water Resources Association Conference
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    • 2016.05a
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    • pp.391-391
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    • 2016
  • 유수동역학적인 요소와 유사의 부유는 서로 상호작용을 주고받으며 다양한 현상을 만들어낸다. 많은 선행연구를 통해 유사 농도 등의 특성이 난류 구조 등의 변화를 야기하며, 변화한 난류 구조 역시 유사의 부유 등에 2차적인 영향을 준다는 점이 확인되었다. 본 연구에서는 가는 유사에 보다 집중하여 유사 부유와 이에 따른 연직구조 특성의 변화를 살펴본다. 본 연구에서는 1차원 연직 모형을 이용하여 수치실험을 수행한다. 본 연구에 이용된 모형은 가는 유사의 특성인 빠른 입자 반응 시간(Particle Response Time)이 가정되는 모형으로 선행연구를 통해 적용성이 검증된 것으로 판단한다. 주요 분석대상은 유사의 농도와 속도경사 간의 관계 등이며, 분석하는 유사 농도 종류는 일반적인 비점착성 유사의 경우에 관심을 가지는 질량 농도에 집중하여 결정된다. 수치실험 수행을 위해서는 정류 흐름, 진동파 흐름 등이 적용되었고 다양한 경우의 가는 유사를 고려하기 위한 실험조건의 변경이 이루어졌다. 수치실험 결과 진동파의 다양한 위상에서 조금씩 달라지는 연직구조가 확인되었다. 이는 보정되는 Schmidt 수의 값과도 연관관계를 가지는 것으로 나타났다. 특히 가는 유사의 경우에도 입자의 크기에 따라 다른 연직구조의 특성이 모의되었으며 이를 통해 수치실험의 경우에도 입자 크기의 고려 하에 매개변수의 보정이 이루어져야 한다는 점을 알 수 있다. 스토크스 수는 입자 반응 시간과 유체 난류 시간규모(Fluid Turbulence Ttime Scale)의 비율을 의미한다. 본 연구를 통해 스토크스 수가 유사의 확산강도 결정과 큰 상관 관계를 가지는 것을 알 수 있다. 이때 유사의 크기와 보정되는 Schmidt 수의 값은 고정되었다. 수치 계산시에 확산계수의 값이 부유 및 이에 따른 연직구조의 특성을 결정하는 중요한 변수라는 점을 고려할 때, 가는 유사의 부유를 모의할 때에는 세심한 주의가 요구된다는 점을 이해할 수 있다. 선행 연구사례를 통해 볼 때 부유하는 입자의 관성력이 Schmidt 수의 결정과 이에 따른 연직 구조의 계산에 큰 영향을 준다는 점을 알 수 있다. 본 연구에서는 스토크스 수를 관성력을 나타낼 수 있는 지표로서 계산하였지만 보다 정량적이고 효율적인 입자 관성력 지표가 제시될 때 효율적인 연구결과의 제시가 이루어질 수 있을 것으로 기대한다.

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A Study on a documentation Area for photography documentation of railway station. (철도역 사진기록화를 위한 영역설정에 관한 연구)

  • Kim, Jeong Hyeon
    • The Korean Journal of Archival Studies
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    • no.30
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    • pp.125-174
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    • 2011
  • Railway Station in Korea built for purpose to plunder resource and invade China 19 and 20 century early, It functioned as main transportation and important role in local history. However, Since the late 1990s, Railway Station in Korea is facing major changes due to Railroad Improvement and Restructuring plan. Photography is useful way to represent memory and local history about railway station, but Photography Documentation on railroad station were not discussed until now due to indifference of the KORAIL and peculiarities of national security facilities for a long time. This study suggest what is document activities and facilities of railway station, use value analysis about railway station's value firstly. next, this study set each documentation area with value analysis for a basis and present concrete example. finally, this study adapt documentation area and detail to classification scheme and apply activities and facilities of supplement or revision to classification scheme.

A Study on Enhancing Brand Recognition in the Research Agency of Geoscience and Mineral Resources (지질자원 전문기관 브랜드인지도 제고방안 연구)

  • Kim, Chan-Souk;Kim, Seong-Yong;Park, Eun-Sook;Choi, Byung-Kwan
    • Economic and Environmental Geology
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    • v.44 no.5
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    • pp.443-449
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    • 2011
  • In this study, we carried out a survey on the degree of recognition for the brand of the Korea Institute of Geoscience and Mineral Resources (KIGAM) to contribute to reestablishing the status and role of KIGAM as an institution that people proud of by effectively delivering KIGAM's various research activities and achievements to people. About 49.9% of external publics recognized that there was relevance between research achievements of geo-technology and national brand. On the contribution of research achievements of geo-technology to promoting Korea's power of science and technology, 42.3% gave positive answers. On research achievements of mineral resources technology, just 14.4% replied they saw such results. As alternatives to promote the degree of recognition for brand, we suggested development of beneficial message, operation of brand management committee, promotion of involvement of research achievements of mineral resources technology about people-friendly subjects, development and distribution of "board game for education on mineral resources technology" for youths, activation of location PR, activation of online Q&A bulletin board, finding out star researchers, and president's PI activities.

Discourse and an Agenda for Religious Publicness: Faith, Sacred Objects, and Holy Sites (종교 공공성의 담론과 의제 - 신앙, 성물과 성지 -)

  • Yoon Yong-bok;Ko Byoung-chul
    • Journal of the Daesoon Academy of Sciences
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    • v.43
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    • pp.31-66
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    • 2022
  • In Korea, the concept of publicness, although conceptually unclear, is being used as a medium between religious groups and other areas of society. In this situation, it is necessary to discuss the concept and agenda of publicness related to religions. For this purpose, we reviewed the relationship and agenda between publicness and faith, and then analyzed the cases of creating sacred objects and holy sites in connection with the concept of publicness. Specifically, according to Chapter II, Publicness and Faith, theologians and sociologists interested in publicness generally presuppose or aim for social participation and change. In this context, the agenda related to religious publicness can include the ground of non-Christian publicness, interreligious equality in the public spheres, the status of religious bodies, and the participation of researchers in the public spheres. In Chapter III, Sacred Objects and Publicness, we divided religious publicness into 'publicness within religion' and 'publicness outside of religion.' According to this classification, rituals are a key factor in creating publicness within religion. Publicness outside of religion is not intrinsic, but is constructed through various external debates. In Chapter IV, Sacred Holy Sites and Publicness, we reviewed cases of the construction of Catholic holy sites and analyzed oppositional logic provided by other religious groups in relation to the publicness outside of religion. Those cases internally created publicness within religion but lead to evaluation and debate about publicness outside of religion in public spheres in which various religions participate. Those who opposed the creation of Catholic holy sites used the logic that Catholicism was eliminating the heritage and values of other religions, and responded by expanding this to include the logic that the Catholics were weakening publicness or creating religious bias.

A Comprehensive Representation Model for Spatial Relations among Regions and Physical Objects considering Property of Container and Gravity (Container 성질과 중력을 고려한 공간과 객체의 통합적 공간관계 표현 모델)

  • Park, Jong-Hee;Lim, Young-Jae
    • Journal of KIISE:Software and Applications
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    • v.37 no.3
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    • pp.194-204
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    • 2010
  • A space, real or virtual, comprises regions as its parts and physical objects residing in them. A coherent and sophisticated representaion scheme for their spatial relations premises the precision and plausibility in its associated agents' inferencing on the spatial relations and the development of events occurring in such a space. The existing spatial models are not suitable for a comprehensive representation of the general spatial relations in that they have limited expressive powers based on the dichotomy between the large and small scales, or support only a small set of topological relations. The representaion model we propose has the following distinctive chracteristics: firstly, our model provides a comprehensive representation scheme to accommodate large and small scale spaces in an integrated fashion; secondly, our model greatly elaborated the spatial relations among the small-scale objects based on their contact relations and the compositional relations among their respective components objects beyond the basic topological relations like disjoint and touch; thirdly, our model further diversifies the types of supported relations by adding the container property besides the soildness together with considering the gravity direction. The resulting integrated spatial knowledge representation scheme considering the gravity allows the diverse spatial relations in the real world to be simulated in a precise manner in relation to the associated spatial events and provides an expression measure for the agents in such a cyber-world to capture the spatial knowledge to be used for recognizing the situations in the spatial aspects.

Improvement of Bit Error Rate through the Optimization of 320 Gbps WDM System with Non Zero-Dispersion Shifted Fiber (비영 분산 천이 광섬유를 갖는 320 Gbps WDM 시스템에서 최적화를 통한 비트 에러율 개선)

  • Lee, Seong-Real;Yim, Hwang-Bin
    • Journal of Advanced Navigation Technology
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    • v.10 no.2
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    • pp.103-113
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    • 2006
  • The numerical methods of finding the optimal position of optical phase conjugator (OPC) and the optimal fiber dispersions are proposed, which are able to effectively compensate overall channels in $8{\times}40$ Gbps WDM system with non zero-dispersion shifted fiber (NZ-DSF) as an optical fiber. And BER characteristics in the system with two induced optimal parameters are compared with those in the system with the currently used mid-span spectral inversion (MSSI) in order to confirm the availability of the proposed methods. It is confirmed that two optimal parameters depend on each other, but less related with the searching procedure. The methods proposed in this research will be expected to alternate with the method of making a symmetrical distribution of power and local dispersion in real optical link which is a serious problem but the condition in the case of applying the OPC into multi-channels WDM system.

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Socio-Spatial Exclusion by Urban Policy Dialectic : ZUS in France (도시정책논리에 의한 사회공간적 배제 : 프랑스 ZUS를 사례로)

  • Jung, In-Chul;Bae, Mi-Ae
    • Journal of the Korean Geographical Society
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    • v.42 no.1 s.118
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    • pp.63-81
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    • 2007
  • This Paper aims to explore the socio-spatial implication of urban policy dialectic. The urban policies to solve various social problems are definitely related to the spatial situation of his society. In France there have been several kinds of urban policies to meet 'social exclusion' as new concept of poverty. To fix 'ZUS(Zones Urbaines Sensibles), being based on the 'Pacte do relance pour la ville' of 1996, is one of them. It makes a conclusion in this paper that the purposeful zoning by urban policy to meet social exclusion can lead to deepen them. The situation of social exclusion in ZUS is related to the spatial exclusion by zoning marginal areas. To define the key concepts of 'social exclusion' and 'ZUS' is absolutely needed to accomplish the purpose of this study.

Design and Optimization of an Knee Joint of Fully-active Transfemoral Prosthesis for Stair Walking (계단 보행을 위한 능동형 대퇴의지 무릎 관절의 설계 및 최적화)

  • Ahn, Hyoung-Jong;Lee, Kwang-Hee;Hong, Yi;Lee, Chul-Hee
    • Journal of rehabilitation welfare engineering & assistive technology
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    • v.10 no.1
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    • pp.65-72
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    • 2016
  • In this study, a fully active transfemoral prothesis with a knee joint is designed considering stair walking conditions. Since the torque at the knee joint required for stair walking condition is relative high compared with the one in normal walking condition, the proposed design has high torque generating mechanism. Moreover, the transfemoral prothesis is designed in compact size to reduce its weight, which is related to comfortable fit and fatigue of patients. Flat type BLDC motor is used for simple and compact structure and various components are used to generate required torque with target working angle and speed. The weight reduction of structure is carried out using optimization method after the initial design process is complete. The optimization is conducted under the load conditions of stair walking. The optimized design is validated via finite element analysis and experiments. As a result, the weight is reduced using topology and shape optimization but maintaining the safety of structure. Also the space efficiency is improved due to its compact size.

The Relationships among Human, Machine, and Thought in Charles Babbage's Calculating Engines (찰스 바비지의 계산기관에서 인간, 기계, 생각의 관계성)

  • Lim, Shan
    • The Journal of the Convergence on Culture Technology
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    • v.5 no.2
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    • pp.111-116
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    • 2019
  • This paper considers the historical background of the emergence of 'thinking-machine,' that has changed the ontological statue of human and machine. In particular, British mathematician Charles Babbage's Calculating Engines is examined as a material iteration of thinking-machine, focusing on the discursive process by which thought is not the faculty of human, but the function of machine. In Chapter II, I review the dualism of René Descartes who denied the possibility of machine intelligence by separating the substance of body and mind. In Chapter III, Babbage's philosophical assertions which emphasized the function of human associated with thought by rejecting the fundamental opposition between human and machine. Therefore, this paper verifies that the conception of 'thinking-machine' essentially causes the reorganization and reformulation of concepts involved with human identity, and provides the sophisticated sources to prepare new perspective on the artificial technology nowadays.

The Structural Equivalence and Role Equivalence of Container Ports in Asia-Europe Container Shipping Networks (아시아-유럽 컨테이너 해운 네트워크 구성 항만의 구조적 등위성과 역할 등위성)

  • Lee, Sang-Yoon
    • Journal of Korea Port Economic Association
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    • v.32 no.2
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    • pp.105-122
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    • 2016
  • Numerous studies have evaluated the status of seaports. However, the majority of the research has approached this topic from the view-point of port capabilities, including locational advantage, infrastructure, productivity, and competitiveness. The position and/or role of a port can be understood more precisely and comprehensively by considering the interconnectivity among ports making up enormous global transportation networks. The main objective of this study is to compare the status of 82 container ports on the trunk shipping routes between Asia and Europe by applying the concepts of structural equivalence and role equivalence proposed by the social network analysis method. Network similarities and differences among competing ports in the regions are assessed by analysing their structural equivalence. Furthermore, the hierarchical structures of the ports located on the trunks between Asia and Northwest Europe and between Asia and the Mediterranean are constructed by evaluating their role equivalence. The results of this empirical research shows that Singapore and Rotterdam possess the most significant positions on the ocean corridors between Asia and Northwest Europe. Singapore also holds a leading position on the Asia-Mediterranean shipping route. Lastly, no ports located in the Middle East or Mediterranean regions have an equivalent weight to those of Rotterdam, Hamburg, Antwerp on the Asia-Northwest Europe route.