• Title/Summary/Keyword: flow theory

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CLUSTERING DNA MICROARRAY DATA BY STOCHASTIC ALGORITHM

  • Shon, Ho-Sun;Kim, Sun-Shin;Wang, Ling;Ryu, Keun-Ho
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.438-441
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    • 2007
  • Recently, due to molecular biology and engineering technology, DNA microarray makes people watch thousands of genes and the state of variation from the tissue samples of living body. With DNA Microarray, it is possible to construct a genetic group that has similar expression patterns and grasp the progress and variation of gene. This paper practices Cluster Analysis which purposes the discovery of biological subgroup or class by using gene expression information. Hence, the purpose of this paper is to predict a new class which is unknown, open leukaemia data are used for the experiment, and MCL (Markov CLustering) algorithm is applied as an analysis method. The MCL algorithm is based on probability and graph flow theory. MCL simulates random walks on a graph using Markov matrices to determine the transition probabilities among nodes of the graph. If you look at closely to the method, first, MCL algorithm should be applied after getting the distance by using Euclidean distance, then inflation and diagonal factors which are tuning modulus should be tuned, and finally the threshold using the average of each column should be gotten to distinguish one class from another class. Our method has improved the accuracy through using the threshold, namely the average of each column. Our experimental result shows about 70% of accuracy in average compared to the class that is known before. Also, for the comparison evaluation to other algorithm, the proposed method compared to and analyzed SOM (Self-Organizing Map) clustering algorithm which is divided into neural network and hierarchical clustering. The method shows the better result when compared to hierarchical clustering. In further study, it should be studied whether there will be a similar result when the parameter of inflation gotten from our experiment is applied to other gene expression data. We are also trying to make a systematic method to improve the accuracy by regulating the factors mentioned above.

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A Study of Posted Speeds on Freeway Exits and Entrances (고속도로 진출구 제한속도에 관한 연구)

  • Im, Geun-Ho;Kim, Hong-Sang;Choe, Hyeon-Seok
    • Journal of Korean Society of Transportation
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    • v.25 no.4
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    • pp.7-19
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    • 2007
  • The purpose of posted speeds is to provide a speed that ensures the safety of vehicle flow according to given road situations. Because of this, posted speeds must be carefully examined, and posted speeds at freeway exits and entrances in particular should consider car characteristics. Posted speeds at freeway exits and entrances must take changing speeds due to curve radiuses into consideration and in this study, an 85th percentile speed becomes the most important element to consider. When it is considered that most traffic accidents occur because of variations in speed between cars, posted speeds should be set after considering car traveling characteristics. Within these dimensions, instead of putting significance on an upper direction regulation or lower direction regulation, speed distributions which fit to the characteristics of each road should be fully considered. Accordingly, this study evaluated appropriate posted speeds that will reduce the dangers of traffic accidents through posted speed regulations of roads now in operation by offering a posted speed setting method theory, using entries at Yangji, Yongin, and Cheongwon interchanges as subjects.

Development of a CFD Model to Study Ventilation Efficiency of Mechanically Ventilated Pig House (강제환기식 돈사의 환기 효율성 분석을 위한 CFD 모델 개발)

  • Seo, Il-Hwan;Lee, In-Bok;Hong, Se-Woon;Hwang, Hyun-Seob;Bitog, Jessie Pascul;Yoo, Jae-In;Kwon, Kyung-Suk;Ha, Tae-Hwan;Kim, Hyeon-Tae
    • Journal of The Korean Society of Agricultural Engineers
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    • v.50 no.1
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    • pp.25-37
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    • 2008
  • When livestock facilities in Korea have been changed larger and denser, rearing conditions have been getting worse and the productivity of animal production have been decreased. Especially in the cold season, the minimized ventilation has generally been operated to save energy cost in Korea resulting in very poor environmental condition and high mortality. While the stability, suitability, and uniformity of the rearing condition are the most important for high productivity, the ventilation configuration is the most important to improve the rearing condition seasonally. But, it is so difficult to analyze the internal air flow and the environmental factors by conducting only field experiment because the weather condition is very unpredictable and unstable as well as the structural specification can not be easily changed by the researchers considering cost and labor. Accordingly, an aerodynamic computer simulation was adopted to this study to overcome the weakness of conducting field experiment and study the aerodynamic itself. It has been supposed that the airflow is the main mechanism of heat, mass, and momentum transfers. To make the simulation model accurately and actually, simplified pig models were also developed. The accuracy of the CFD simulation model was enhanced by 4.4 % of errors compared with the data collected from field experiments. In this paper, using the verified CFD model, the CFD computed internal rearing condition of the mechanically ventilated pig house were analyzed quantitatively as well as qualitatively. Later, this developed model will be computed time-dependently to effectively analyze the seasonal ventilation efficiency more practically and extensively with tracer gas decay theory.

A Study of Traffic Flow Characteristics for Estimating Queue-Length in Highway (고속도로 대기행렬 길이 산정모형 개발을 위한 연속류 특성 분석)

  • 노재현
    • Proceedings of the KOR-KST Conference
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    • 1998.10b
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    • pp.297-297
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    • 1998
  • 고속도로의 교통혼잡을 관리하기 위해서는 근본적으로 혼잡지점 상류부의 진입교통량을 제어해야 한다. 이를 위한 효과적인 램프미터링 운영전략이나 고속도로 교통정보제공방안을 수립하기 위해서는 혼잡영향권(대기행렬길이)에 관한 신뢰성 있는 데이터가 반드시 필요하다. 고속도로의 대기행렬길이를 산정하기 위해 일반적으로 충격파이론과 Queueing이론을 제시하고 있다. 그러나, 기존의 충격파 이론을 포물선형의 교통량-밀도관계식을 근거로 하고 있어 충격파간에 발생하는 부수적인 충격파를 해석하는 과정이 수학적으로 불가능하여 실질적인 목적으로 사용할 수 없음은 이미 잘 알고 있는 사실이다. 최근에 이러한 한계를 극복할 수 있는 새로운 방법으로 교통량 밀도간의 관계식을 삼각형으로 가정하고 교통량 대신에 누적교통량을 사용하는 Simplified Theory of Kinematic Waves In Highway Traffic이 개발(Newell, 1993)되었지만, 이 방법을 적용하기 위해서는 기본적으로 대상 고속도로 구간의 교통량-밀도관계식을 규명해야 하는 어려움이 있다.(사실 실시간으로 밀도데이터를 수집하기란 불가능하다.) Queueing이론에서 제시하는 대기행렬은 모두 대기차량이 병목지점에 수직으로 정렬하여 도로를 점유하지 않는 Point Queue(혹은 Vertical stack Queue)로서 실제로 도로상에 정렬된 대기행렬(Real Physical Queue)과는 전혀 다르다. 이미 입증된 바 있어, Queueing이론을 이용함은 타당성이 없다. 이러한 사실에 근거하여 본 연구는 고속도로 대기행렬길이를 산정할 수 있는 모형개발을 위한 기초연구로서 혼잡상태의 연속류 특성을 분석하는데 목적이 있다. 이를 위해, 본 연구에서는 서울시 도시고속도로에서 수집한 실제 데이터를 이용하여 진입램프지점의 혼잡상태에서 대기행렬의 증가 또는 감소하는 과정을 분석하였다. 주요 분석결과는 다음과 같다. 1. 혼잡초기의 대기행렬은 다른 혼잡시기에 비해 상대적으로 급속한 속도로 증가함. 2. 혼잡초기의 대기행렬의 밀도는 다른 혼잡시기에 비해 비교적 낮음. 3. 위의 두 결과는 서로 관계가 있으며, 혼잡시 운전자의 행태(차두간격)과 혼잡기간중에도 변화함을 의미함. 4. 교통변수 중에서 대기행렬길이를 산정하는데 적합한 교통변수를 교통량과 밀도로 판단됨. 5. Queueing이론에서 제시하는 대리행렬길이 산정방법인 대기차량대수$\times$평균차두간격은 대기행렬내 밀도가 일정하지 않아 부적합함을 재확인함. 6. 혼잡초기를 제외한 혼잡기간 중 대기행렬길이는 밀도데이터 없이도 혼잡 상류부의 도착교통량과 병목지점 본선통과교통량만을 이용하여 추정이 가능함. 7. 이상에 연구한 결과를 토대로, 고속도로 대기행렬길이를 산정할 수 있는 기초적인 도형을 제시함.

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A Study of Automation for Examination Analysis of Inservice Inspection for Nuclear Power Plant (I) (원자력발전소(原子力發電所) 가동중(稼動中) 검사(檢査)의 시험분석(試驗分析)을 위한 자동화연구(自動化硏究) (I))

  • Kim, W.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.5 no.1
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    • pp.34-47
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    • 1985
  • The developing country, KOREA where does not possess the natural resources for traditional energy such as oil and gas, so. The nuclear energy is the most single reliable source available for closing the energy gap. For these reason, It is inavoidable to construct the nuclear power plant and to develop technology related nuclear energy. The rate of operation in large nuclear power facilities depends upon the performance of work system through design and construction, and also the applied technology. Especially, it is the most important element that safety and reliability in operation of nuclear power plant. In view of this aspects, Nuclear power plant is performed severe examinations during preservice and inservice inspection. This study provide an automation of analysis for volumetric examination which is required to nuclear power plant components. It is composed as follows: I. Introduction II. Inservice Inspection of Nuclear Power Plant ${\ast}$ General Requirement. ${\ast}$ Principle and Methods of Ultrasonic Test. ${\ast}$ Study of Flaw Evaluation and Design of Classifying Formula for Flaws. III. Design of Automation for Flaw Evaluation. IV. An Example V. Conclusion In this theory, It is classifying the flaws, the formula of classifying flaws and the design of automation that is the main important point. As motioned the above, Owing to such as automatic design, more time could be allocated to practical test than that of evaluation of defects, Protecting against subjective bias tester by himself and miscalculation by dint of various process of computation. For the more, adopting this method would be used to more retaining for many test data and comparative evaluating during successive inspection intervals. Inspite of limitation for testing method and required application to test components, it provide useful application to flow evaluation for volumetric examination. Owing to the characteristics of nuclear power plant that is highly skill intensive industry and has huze system, the more notice should be concentrated as follows. Establishing rational operation plan, developing various technology, and making the newly designed system for undeveloped sector.

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Optimum Welding Position between Shell and Cylinder based on SEA (SEA 를 이용한 쉘과 실린더의 최적 용접 조건)

  • Ahn, Byoung-Ha;Lee, Jang-Woo;Jeon, Simon;Yang, Bo-Suk
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2012.10a
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    • pp.258-264
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    • 2012
  • The overall aim of this paper is to determine coupling loss factor of welding point between shell and cylinder using loss factor and structural loss factor. For this purpose, two kinds of loss factor were adopted. One is loss factor of each sub structure, another is structural loss factor based on the complex welded or assembled structure. Using these two parameters, it is possible to derive the coupling loss factor which represents characteristic condition of SEA theory. Coupling loss factor of conjunction in complex structure was expressed as power balance equation. The derived equation for a coupling loss factor has been simplified on the assumption of one way (uni-directional) power flow between multi-sub structures. Using these conditions, it is possible to find the equation of coupling loss factor expressed as above two loss factors. To check the effectiveness of above equation, this paper used two-stage application. The first approach was application between simple cylinder and shell. The next was adopted rotary compressor. Rotary compressor has three main conjunctions between shell and internal vibration part. This equation was applied to find out the optimum welding point with respect to reduce the noise propagation. It shows the effective tool to evaluate the coupling loss factor in complex structure.

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Philosophical and Theoretical Perspectives of Five Laws of Libraries and its Influence on the Library Profession: Issues and Challenges

  • Krishnamurthy, M.
    • Journal of the Korean Society for Library and Information Science
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    • v.45 no.4
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    • pp.271-286
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    • 2011
  • The role of information in knowledge society has changed. Library refers to information centre, which is actively involved information collection and promoting use of for the development of individual and society. Modern libraries are the centres of interaction for all interested in accessing information and in participating in the marathon of the present competitive age. Information and a conducive environment of its free flow is a vital tool in all forms of human endeavour. It is the link pin of national development. For a nation to develop it needs to have and provide relevant, updated and adequate information on food security, health, democracy, population, education, family planning, youth empowerment, gender quality, environment etc. The information intermediaries are the persons to modulate these complexities and find match between the information sources and users needs to satisfaction of Ranganathan's law: Books are for use; Every reader his/her book; Every book its reader; Save the time of the reader; Library is a growing organism. The relative importance of these norms in modern context has been evident from experience, study, observations, discussions, etc., and only by scientists and technologists, but also by managers, planners, and policy makers. They recognize the usefulness of information in the performance of their needs information needs. Libraries are therefore proper management, provision and dissemination of such information. It is clearly visible in the contemporary context, that the libraries in the knowledge society are much more than the book depositories This article looks at the theory/practice divide in library and information science and particularly Ranganathan's contributions, basic statements remain as valid in substance if not in expression as -to-day as when they were promulgated, concisely representing the ideal service and organizational philosophy of libraries today.

A Qualitative Exploration of Folksonomy Users' Tagging Behaviors (폭소노미에 따른 웹 분류 연구 - 이용자 태깅 행위 분석을 중심으로 -)

  • Park, Hee-Jin
    • Journal of the Korean Society for Library and Information Science
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    • v.45 no.1
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    • pp.189-210
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    • 2011
  • This study aims to explore how users are tagging in order to utilize a folksonomy and whether they understand the social and interactive aspects of tagging in three different folksonomic systems, Connotea (www.connotea.org), Delicious(http://delicious.com), and CiteULike(www.citeulike.org). The study uses internet questionnaires, qualitative diary studies, and follow-up interviews to understand twelve participants' tagging activities associated with folksonomic interactions. The flow charts developed from the twelve participants showed that tagging was a quite complex process, in which each tagging activity was interconnected, and a variety of folksonomic system features were employed. Three main tagging activities involved in the tagging processes have been identified: item selection, tag assignment, and tag searching and discovery. During the tag assignment, participants would describe their tagging motivations related to various types of tags. Their perception of the usefulness of types of tags was different when their purpose was for social sharing rather than personal information management. While tagging, participants recognized the social potential of a folksonomic system and used interactive aspects of tagging via various features of the folksonomic system. It is hoped that this empirical study will provide insight into theoretical and practical issues regarding users' perceptions and use of folksonomy in accessing, sharing, and navigating internet resources.

The estimation of friction coefficient by using entropy theory in open channels (엔트로피 이론에 의한 개수로 마찰계수 산정)

  • Choo, Tai Ho;Kwak, Kil Sin;Yun, Gwan Seon;Yoon, Hyeon Cheol
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.4
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    • pp.2868-2875
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    • 2015
  • Both the friction velocity and the friction coefficient have to be estimated to determine flow characteristic in an open channel. In spite of the importances in an open channel, the complete interpretation is highly difficult because of free water surface, the complex of cross section and the various hydraulic parameters. The researches related to the friction factor are based on empirical outcome. Therefore, the equations are difficult to be generally applied. For that reason, the new friction factor estimation equation using the entropy concept was proposed in the present study, and the data measured in rectangular and trapezoid cross sections was used to verify the accuracy of equation. The advantage of the proposed equation dose not use the energy slope term which is difficult to be measured and to be estimated in an open channel. In addition, the proposed method showed that the accurate friction factor f can be estimated on the Basis of theoretical background.

Hardware Synthesis From Coarse-Grained Dataflow Specification For Fast HW/SW Cosynthesis (빠른 하드웨어/소프트웨어 통합합성을 위한 데이타플로우 명세로부터의 하드웨어 합성)

  • Jung, Hyun-Uk;Ha, Soon-Hoi
    • Journal of KIISE:Computer Systems and Theory
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    • v.32 no.5
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    • pp.232-242
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    • 2005
  • This paper concerns automatic hardware synthesis from data flow graph (DFG) specification for fast HW/SW cosynthesis. A node in BFG represents a coarse grain block such as FIR and DCT and a port in a block may consume multiple data samples per invocation, which distinguishes our approach from behavioral synthesis and complicates the problem. In the presented design methodology, a dataflow graph with specified algorithm can be mapped to various hardware structures according to the resource allocation and schedule information. This simplifies the management of the area/performance tradeoff in hardware design and widens the design space of hardware implementation of a dataflow graph compared with the previous approaches. Through experiments with some examples, the usefulness of the proposed technique is demonstrated.