• Title/Summary/Keyword: mechanism

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A Study on the Reliability of Oriental OB & GY Diagnosis Questionnaires (한방부인과 진단설문지의 신뢰도연구)

  • Min Byeong-Hwa;Um Yun-Kyung;Kim Mi-Jin;Cho Hye-Sook;Kong Bok-Cheul;Lee Yong-Tae;Kim Gyu-Gon;Lee In-Seon
    • The Journal of Korean Medicine
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    • v.26 no.2 s.62
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    • pp.126-139
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    • 2005
  • Objective: This study was undertaken to examine the reliability of disease mechanism diagnosis, estimate the disease mechanism items of questionnaires and inquire about the relation of disease mechanisms to the oriental OB & GY diagnosis program. Questionnaires and abridged questionnaires were used for the object diagnosis of oriental medicine in the dept of Oriental OB & GY, Oriental Medical Hospital of Dong-Eui University. Methods: We analyzed the results of questionnaires about 1706 outpatients who had OB & GY disease in the Oriental Medical Hospital of Dong-Eui University from April 2000 to March 2004. Results: 1. The reliability of Oriental OB & GY questionnaires between $90\%$ and $95\%$ were 9 cases, between $85\%$ and $90\%$ were 3 cases, and under $85\%$were 3 cases. Abridged questionnaires were lower than original questionnaires, but 12 cases of a total 15 cases of disease mechanism were above $85\%$. Therefore, both abridged questionnaires and original questionnaires had similar results. 2. Abridged questionnaires were usually lower than existing questionnaires in the comparison of disease mechanism output frequency and that of disease mechanism average score. Therefore, the results of abridged questionnaires seemed to be poorer than those of existing questionnaires, but a great difference wasn't seen. 3. Disease mechanism that was over $50\%$ in the rate of pure question per disease mechanism was 10 cases $(66.7\%)$. Disease mechanism that contributed to producing disease mechanism result and in which pure question was over relevance calculation 0.9 was also 10 cases $(66.7\%)$. In abridged questionnaires, the duplication of questions per disease mechanism Was decreased, the rate of pure questions was increased, and the number of related disease mechanisms was decreased by abridgment of the questionnaires' questions. 4. The calculation of disease mechanism went with the increase of the duplication of questions in many cases, but Tam­Umhe, Kihe-Hyule, Kihe-Umhe, and Shin-Tam went with disease mechanism in many cases despite no duplication of questions. Conclusions: About the reliability of Oriental OB & GY questionnaires, 12 of a total 15 cases of disease mechanism were above $85\%$; therefore both abridged questionnaires and original questionnaires had similar results.

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A Study on the Reduction of Reaction Mechanism for the Ignition of Dimethyl Ether (디메틸 에테르 착화에 관한 반응기구 축소 연구)

  • Ryu, Bong-Woo;Park, Sung-Wook;Lee, Chang-Sik
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.35 no.1
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    • pp.75-82
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    • 2011
  • The numerical analysis of the reduction of reaction mechanism for the ignition of dimethyl ether (DME) was performed. On the basis of a detailed reaction mechanism involving 79 species and 351 reactions, the peak molar concentration and sensitivity analysis were conducted in a homogeneous reactor model. The reduced reaction mechanism involving 44 species and 166 reactions at the threshold value $7.5{\times}10^{-5}$ of the molar peak concentration was established by comparing the ignition delays the reduced mechanism with those the detailed mechanism. The predicted results of the reduced mechanism applied to the single-zone homogeneous charge compression ignition (HCCI) engine model were in agreement with those of the detailed mechanism. Therefore, this reduced mechanism can be used to accurately simulate the ignition and combustion process of compression ignition engine using DME fuel.

The Role of Domain-specific Causal Mechanism and Domain-general Conditional Probability in Young Children's Causal Reasoning on Physics and Psychology (영역특정론과 영역일반론에 따른 유아의 인과추론 - 물리, 심리 영역을 중심으로 -)

  • Kim, Jihyun;Yi, Soon Hyung
    • Korean Journal of Child Studies
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    • v.29 no.5
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    • pp.243-269
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    • 2008
  • The role of domain-specific causal mechanism information and domain-general conditional probability in young children's causal reasoning on physics and psychology was investigated with the participation of 121 3-year-olds and 121 4-year-olds recruited from seven child care centers in Seoul, Kyonggi Province, and Busan. Children watched moving pictures on physical and psychological phenomena, and were asked to choose an appropriate cause and justify their choice. Results showed that young children's causal reasoning differed depending on domain-specific mechanism. In addition, their causal reasoning on physics and psychology differed by the developmental level of causal mechanism. The interaction of domain-specific mechanism and domain-general conditional probability influenced children's causal reasoning : evident conditional probability between domain-appropriate cause and effect helped children make more inferences based on domain-specific causal mechanism.

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Quantum-behaved Electromagnetism-like Mechanism Algorithm for Economic Load Dispatch of Power System

  • Zhisheng, Zhang;Wenjie, Gong;Xiaoyan, Duan
    • Journal of Electrical Engineering and Technology
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    • v.10 no.4
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    • pp.1415-1421
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    • 2015
  • This paper presents a new algorithm called Quantum-behaved Electromagnetism-like Mechanism Algorithm which is used to solve economic load dispatch of power system. Electromagnetism-like mechanism algorithm simulates attraction and repulsion mechanism for particles in the electromagnetic field. Every solution is a charged particle, and it move to optimum solution according to certain criteria. Quantum-behaved electromagnetism-like mechanism algorithm merges quantum computing theory with electromagnetism-like mechanism algorithm. Superposition characteristic of quantum methodology can make a single particle present several states, and the characteristic potentially increases population diversity. Probability representation of quantum methodology is to make particle state be presented according to a certain probability. And the quantum rotation gates are used to realize update operation of particles. The algorithm is tested for 13-generator system and 40-generator system, which validates it can effectively solve economic load dispatch problem. Through performance comparison, it is obvious the solution is superior to other optimization algorithm.

An Optimal Design Study of an Equilibrating-Mechanism for the Unbalanced Elevation-Drive System (정적 불균형 모멘트가 존재하는 고저구동장치의 평형 메카니즘 최적설계 연구)

  • Park, Keun-Kuk;Lee, Man-Hyung;Kim, Dong-Hyun;Ahn, Rae-Young
    • Journal of Institute of Control, Robotics and Systems
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    • v.6 no.11
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    • pp.1033-1038
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    • 2000
  • The unbalanced heavy-loaded elevation-drive system is composed of a hydraulic cylinder, a driving link-mechanism and an equilibrating-mechanism which compensate the static unbalanced moment of the elevation load. The Compensator for the unbalanced moment is composed of a hydrau-pneumatic accumulator and a hydraulic cylinder which act with the elevation cylinder together. Compensation of the variable static-unbalanced moment for the elevation-drive system is very difficult because these mechanisms imply highly nonlinear properties due to air conditioning characteristics and mechanical rotation of the link-mechanism. In this study, through the analysis of the already designed equilibrating-mechanism, the optimal design parameters of the equilibrating-mechanism is suggested.

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Aeroelastic Analysis in Frequency Domain for Wings with Double-Folding Mechanism (주파수 영역에서의 2단 접는 날개 공탄성 해석)

  • Kang, Myung-Koo;Kim, Ki-Un
    • Journal of the Korea Institute of Military Science and Technology
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    • v.9 no.4
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    • pp.104-113
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    • 2006
  • To identify aeroelastic characteristics of wings with double-folding mechanism, aeroelastic analyses are performed. There are four wing models which consist of one linear model and three nonlinear models. The nonlinear models have one or two freeplay nonlinearties. The describing function method is used to approximately examine nonlinear effects. The aeroelastic module in MSC/NASTRAN is used to study the aeroelastic characteristics of the considered wing models. The effects of the folding mechanism and amplitude ratio are examined. As the amplitude ratio increases, the flutter speeds approach to those of the wing model with only one nonlinearity. The numerical results show that the flutter speeds of the wings with double-folding mechanism can be lower or higher than those of the wing model with only one folding mechanism depending upon the direction of the second folding mechanism.

Optimal SMDP-Based Connection Admission Control Mechanism in Cognitive Radio Sensor Networks

  • Hosseini, Elahe;Berangi, Reza
    • ETRI Journal
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    • v.39 no.3
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    • pp.345-352
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    • 2017
  • Traffic management is a highly beneficial mechanism for satisfying quality-of-service requirements and overcoming the resource scarcity problems in networks. This paper introduces an optimal connection admission control mechanism to decrease the packet loss ratio and end-to-end delay in cognitive radio sensor networks (CRSNs). This mechanism admits data flows based on the value of information sent by the sensor nodes, the network state, and the estimated required resources of the data flows. The number of required channels of each data flow is estimated using a proposed formula that is inspired by a graph coloring approach. The proposed admission control mechanism is formulated as a semi-Markov decision process and a linear programming problem is derived to obtain the optimal admission control policy for obtaining the maximum reward. Simulation results demonstrate that the proposed mechanism outperforms a recently proposed admission control mechanism in CRSNs.

Flexibility Analysis of 4-Bar Linkage Mechanism (4절 링크기구의 유연성 해석)

  • 조선휘;박종근;한성현
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.6
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    • pp.1365-1373
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    • 1994
  • Elasto-dynamic deformation of flexible linkage mechanism was analyzed using the finite element method. A computer program was constructed and applied to analyze a specific crank-level 4-bar mechanism, in which the elasto-dynamic deformation of the mechanism system was obtained using mode superposition method in the case of constant input speed and the effect of geometric stiffness on the mechanism is included. Experimental verification of numerical results was conducted by measuring the elasto-dynamic deformation of mid-points of coupler and lever for the 4-bar lingkage mechanism using high speed camera and image data processing systeem. For the elasto-dynamic deformation at the lever mid-point, the numerical results including geometric stiffness almost agree with the experimental ones. However, the numerical results excluding geometric stiffness good agree with the experimental ones at the couper mid-point.

A Study on the Determination of the Main Design Parameters for the Development of Marine Stirling Engines (박용 스터링엔진 개발을 위한 주설계변수 결정에 관한 연구)

  • 이택희;이명호;이종원
    • Journal of Advanced Marine Engineering and Technology
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    • v.17 no.4
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    • pp.63-72
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    • 1993
  • This paper deals with the determination of the main design parameters on the efficient .betha. type stirling engine for marine use having the rhombic drive mechanism. This studies are performed as following. (1) The characteristics of $\beta$ type stirling engine, (2) The kinds of driving mechanism, (3) The structure of rhombic drive mechanism, (4) The reasons of making choice of the rhombic drive mechanism in $\beta$ type stirling engines, (5) Ultimately the purpose of this paper is to determine the main design parameters of $\beta$ type stirling engines for marine use having the rhombic drive mechanism. Finally, We can adapt the result of this paper in designing of $\beta$ type stirling engine driven by the rhombic drive mechanism.

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A design of parallel mechanism to improve the workspace of platform (플랫폼의 운동성을 향상시킨 병렬 기구의 설계)

  • 유재명;최기훈;김영탁
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.1655-1658
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    • 2003
  • The application area of parallel mechanism is limited in spite of many advantages of that because the workspace of platform is a very small. Thus enlargement of workspace is important issue in design of parallel mechanism. In this paper a parallel mechanism design method is described using commercial simulation program. Firstly strokes of the assembled parallel mechanism's active joints are simulated from kinetic simulation mode to get required workspace, Secondly, dynamic parameters(velocity, acceleration, force, moment) are simulated for the gravity, friction and exit load. Finally, workspace of moving platform is displayed and workspace of area is simulated by motion analysis. The results of this paper will help engineer to design parallel mechanism with optimize workspace.

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