• 한국CDE학회논문집
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• 제14권1호
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• pp.18-24
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• 2009

This paper proposes an analytical method of evaluating the maximum error by modeling the exact tool path for the tool traverse singular region in five-axis machining. It is known that the NC data from the inverse kinematics transformation of 5-axis machining can generate singular positions where incoherent movements of the rotary axes can appear. These lead to unexpected errors and abrupt operations, resulting in scoring on the machined surface. To resolve this problem, previous methods have calculated several tool positions during a singular operation, using inverse kinematics equations to predict tool trajectory and approximate the maximum error. This type of numerical approach, configuring the tool trajectory, requires much computation time to obtain a sufficient number of tool positions in a region. We have derived an analytical equation for the tool trajectory in a singular area by modeling the tool operation into a linear and a nonlinear part that is a general form of the tool trajectory in the singular area and that is suitable for all types of five-axis machine tools. In addition, we have evaluated the maximum tool-path error exactly, using our analytical model. Our algorithm can be used to modify NC data, making the operation smoother and bringing any errors to within tolerance.

• 한국정밀공학회지
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• 제12권10호
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• pp.102-112
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• 1995

Temperature distribution on the rake face and flank face in orthogonal turning with cutting tool of high speed steel is studied by using a finite element method and experiments. Experiments are carried out to verify the validity of the temperature measurement by using a thermoelectric couple junction imbedded in a cutting tool of high speed steel. Good agreement is obtained between the analytical results and the experimental ones for the temperature distributions on both the rake face and flank face of cutting tool with high speed steel. The analytical results show that the temperature on the top flank face of a tool is higher than it on the top rake face of the tool because of the difference of the friction velocity on each face of the tool.

• Structural Engineering and Mechanics
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• 제34권3호
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• pp.301-317
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• 2010

This paper studies the reliability of an analytical tool for predicting the lateral load-deformation response of RC columns while subjected to lateral cyclic displacements and axial load. The analytical tool in this study is based on a fiber element model implemented into the program DRAIN-2DX (fiber element). The response of RC column under cyclic displacement is defined by the behavior of concrete, and reinforcing steel under general reversed-cyclic loading. A tri-linear stress-strain relationship for the cyclic behavior of steel is proposed and the improvement in the analytical results is studied. This study only considers the behavior of columns with flexural dominant mode of failure. It is concluded that with the implementation of appropriate constitutive material models, the described analytical tools can predict the response of the columns with reasonable accuracy when compared to experimental data.

• 대한기계학회논문집A
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• 제20권1호
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• pp.222-231
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• 1996

Temperature distribution on the flank face in orthogonal turning with cutting tool of high speed steel is studied by using a finite element method and experiments. Experiments are carried out to verify the validity of the temperature measurement by using a thermoelectric couple junciton imbedded in a cutting tool of high speed steel. Good agreement is obtained between the analytical results and the experimental ones for the temperature distributions on flank face of cutting tool with igh speed steel. The analytical results show that the temperature on the top flank face of a tool is higher because of the difference of the friction velocity on each face of the tool.

• Journal of Advanced Marine Engineering and Technology
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• 제19권1호
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• pp.45-53
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• 1995

Temperature distribution on flank face in orthogonal turning with cutting tool of high speed steel is studied by using a finite element method and experiments. Experiments are carried out to verify the validity of the temperature measurement by using a thermoelectric couple junction imbedded in a cutting tool of high speed steel. Good agreement is obtained between the analytical results and the experimental ones for the temperature distributions on flank face of cutting tool with high speed steel. The analytical results show that the temperature on the top flank face of a tool is higher because of the difference of the friction velocity on each face of the tool.

• 대한기계학회논문집A
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• 제36권2호
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• pp.165-171
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• 2012

본 연구는 3 축 공작기계에 있어 기하학적 오차가 체적 오차에 미치는 영향을 해석적 방법으로 분석하는데 목적이 있다. 먼저 기하학적 오차가 공작기계의 체적 오차에 미치는 영향을 제시하는 수학적 모델인 오차합성모델에 대해 분석한다. 민감도 분석은 분산 기반의 방법(Variance based method)을 사용하였으며 해석적 방법으로 분석하기 위해 평균 및 분산에 대해 목적 함수의 유형별로 그 해를 제시한다. 마지막으로 3 축 공작기계의 예를 들어 민감도 분석을 하였다.

• 대한임상검사과학회지
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• 제42권1호
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• pp.16-21
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• 2010

It has been well known that organic industrial solvents such as toluene, xylene and styrene are environmental health hazards causing occupational diseases to workers. The detection of biological metabolites of toluene, xylene and styrene in blood, urine, breast milk, saliva, and hair of workers exposed to these organic industrial solvents is a useful tool for assessing the amount of organic industrial solvents. Therefor, the external analytical quality assurance program is extremely important work for increasing reliability of the data analyzed in the special health examination laboratory. We evaluated the results of analysis by Korean analytical quality assurance program from the second half 2007 to the first half 2009. The number of participants for analytical quality assurance program for both mandatory item and one of optional items, hippuric acid and methylhippuric acid were 116-122, 116-122 and 105-115 laboratories, respectively. The proficient rate of the special health examination laboratories analyzed both mandatory item and optional item, hippuric acid and methylhippuric acid were 92-98%, 92-98% and 96-98%, respectively. We can conclude from our data that the analytical quality assurance program is a essential tool for improvement of reliability on the data analyzed in the special health examination laboratories.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 춘계학술대회 논문집
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• pp.568-573
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• 1996

In this paper, A design strategy of the Surface Mounting Device for accurate and better performance is studied. Analytical Modeling. Sensitivity analysis and optimization are being conducted. The ANSYS software and experimental method are used for verification of the analytical equations withboundary conditons. Through the sensitivity analysis, the most dominant design parameters can be detected. The optimum design parameters for performing given performing given perfomances are selected by using the optimization algorithm. The design tool based on the design strategy for the analysis, modeling and optimization will be useful for a re-design and better perofrmance of the SMD.

• 한국정밀공학회지
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• 제14권2호
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• pp.120-128
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• 1997

In this paper, A design strategy of the Surface Mounting Device for accurate and better performance is studied. Analytical modeling, sensitivity analysis, and optimization are being conducted. The ANSYS software and experimental method are used for the verification of the analytical equations with boundary conditions. Through the sensitivity analysis, the most dominant design parameter can be detected. The optimum design parameters for improving the given performances are selected by using the optimiza- tion algorithm. The design tool based on the design strategy for the analysis, modeling, and optimization will be useful for are-design and better improving of the SMD.

• International Journal of Computer Science & Network Security
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• 제21권3호
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• pp.134-140
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• 2021

The development of technology speeds up the process of obtaining information and its analysis to track the level of corruption in different countries and develop countermeasures. This study examines the role of information and analytical support of anti-corruption policy as a tool for government accountability and analysis, evaluation, combating corruption in Eastern Europe. The purpose of the article is to identify the components of the information-analytical system that help reduce the level of corruption. The research methodology is based on a qualitative content analysis of the functioning of information and analytical systems of Ukraine used by anti-corruption bodies. A quantitative analysis of the CPI score was conducted, according to Transparency International, to identify the effectiveness of anti-corruption policies in developing countries. The results show similar trends in countries developing on the effect of the use of information and analytical systems in the implementation of anti-corruption policies, strategies and measures. The strategy to combat corruption mainly involves increasing the independence and powers of anti-corruption bodies. Therefore, the development of information and analytical support is aimed at automating the processes of pre-trial investigations and criminal proceedings, information protection. As a tool for accountability, information and analytical systems may be ineffective due to the abuse of power by higher anti-corruption bodies due to political pressure from elite structures. Restrictions on political will are a major problem for the effectiveness of anti-corruption policies.