• International Journal of Quality Innovation
• /
• 제8권1호
• /
• pp.137-153
• /
• 2007

Failure mode and effects analysis (FMEA) is a preventive technique in reliability management field. The successful implementation of FMEA technique can avoid or reduce the probability of system failure and achieve good product quality. The FMEA technique had applied in vest scopes which include aerospace, automatic, electronic, mechanic and service industry. The marking process is one of the back ends testing process that is the final process in semiconductor process. The marking process failure can cause bad final product quality and return although is not a primary process. So, how to improve the quality of marking process is one of important production job for semiconductor testing factory. This research firstly implements FMEA technique in laser marking process improvement on semiconductor testing factory and finds out which subsystem has priority failure risk. Secondly, a CCD position solution for priority failure risk subsystem is provided and evaluated. According analysis result, FMEA and CCD position implementation solution for laser marking process improvement can increase yield rate and reduce production cost. Implementation method of this research can provide semiconductor testing factory for reference in laser marking process improvement.

• Structural Engineering and Mechanics
• /
• 제68권5호
• /
• pp.549-561
• /
• 2018

Sobol method is applied as a powerful variance decomposition technique in the field of global sensitivity analysis (GSA). The paper is devoted to increase convergence speed of the extracted Sobol indices using a new proposed sampling technique called genetic based Latine hypercube sampling (GBLHS). This technique is indeed an improved version of restricted Latine hypercube sampling (LHS) and the optimization algorithm is inspired from genetic algorithm in a new approach. The new approach is based on the optimization of minimax value of LHS arrays using manipulation of array indices as chromosomes in genetic algorithm. The improved Sobol method is implemented to perform factor prioritization and fixing of an uncertain comprehensive high speed rotor-bearing system. The finite element method is employed for rotor-bearing modeling by considering Eshleman-Eubanks assumption and interaction of axial force on the rotor whirling behavior. The performance of the GBLHS technique are compared with the Monte Carlo Simulation (MCS), LHS and Optimized LHS (Minimax. criteria). Comparison of the GBLHS with other techniques demonstrates its capability for increasing convergence speed of the sensitivity indices and improving computational time of the GSA.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2005년도 학술발표회(1)
• /
• pp.482-484
• /
• 2005

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2000년도 전력전자학술대회 논문집
• /
• pp.480-484
• /
• 2000

The pole placement technique for control design of the current mode controlled DC-DC switchmode power converter is proposed. It is compared with conventional transfer function analysis. Using the pole placement technique control design automation algorithm, by computer-based tool is presented. Control design example with large signal simulation is shown.

• 대한간호
• /
• 제27권2호통권145호
• /
• pp.83-98
• /
• 1988

Relaxation technique is an independent nursing intervention used in various stressful situation. This study is aimed at analyzing the research trend trend and effect of relaxation technique, suggesting the direction of future researches, and contributing

• 국제학술발표논문집
• /
• The 3th International Conference on Construction Engineering and Project Management
• /
• pp.432-439
• /
• 2009

This research project was carried out to develop the technique to assess quantitatively and rapidly the stability of a tunnel by using the measured displacement at the tunnel construction site under excavation. To achieve this purpose, a critical strain concept was introduced and applied to an assessment of a tunnel under construction. The new technique calculates numerically the strains of the surrounding ground by using the measured displacements during excavation. A numerical practical system was developed based on the proposed analysis technique in this study. The feasibility of the developed analysis module was verified by incorporating the analysis results obtained by commercial programs into the developed analysis module. To verify the feasibility of the developed analysis module, analysis results of models both elastic and elasto-plastic grounds were investigated for the circular tunnel design. Then the measured displacements obtained in the field are utilized practically to assess the safety of tunnels using critical strain concept. It was verified that stress conditions of in-situ ground and ground material properties were accurately assessed by inputting the calculated displacement obtained by commercial program into this module for the elastic ground. However for the elasto-plastic ground, analysis module can reproduce the initial conditions more closely for the soft rock ground than for the weathered soil ground. The stability of tunnels evaluated with two types of strains, that is, the strains obtained by dividing the crown displacement into a tunnel size and the strains obtained by using the analysis module. From this study, it is confirmed that the critical strain concept can be fully adopted within the engineering judgment in practical tunnel problems and the developed module can be used as a reasonable tool for the assessment of the tunnel stability in the field.

• 한국전산구조공학회논문집
• /
• 제12권3호
• /
• pp.437-445
• /
• 1999

본 논문에서는 다지지점 가진에 의한 구조물의 동적응답을 구하기 위하여 유한요소모형을 수정하고 등가하중을 도입하는 간단한 기법을 제안하였다. 제안방법은 다지지점 입력에 대한 해석기능이 있는 기존의 범용구조해석 S/W를 이용한 선형 및 비선형 해석결과와 비교하여 검증하였다. 이 기법은 다지지점 입력에 대한 해석기능이 없는 범용유한요소해석 S/W 및 비선형 구조해석을 위하여 특별히 개발되었던 전산프로그램을 이용하여 다지지점 입력에 대한 지진응답해석을 수행할 때 유용하게 활용될 수 있을 것으로 기대된다.

• Journal of Electrical Engineering and Technology
• /
• 제10권5호
• /
• pp.2046-2051
• /
• 2015

Currently, most high-voltage gas circuit breakers (CBs) include asymmetrical geometries in the shield, the tank, the hot-gas exhaust, and the connection parts for bushings. For this reason, a 3-dimensional (3-D) analysis of the insulation capability is necessary, rather than a 2-D analysis. However, a 3-D analysis has difficulties due to the computational time and complex modeling. This paper presents a 3-D analysis considering the asymmetry in high-voltage gas CBs and a technique to reduce the calculation time. In the proposed technique, the arc plasma requiring the most computational time is first calculated by a 2-D analysis. Then, the results such as pressure, temperature, and velocity are input as a source for the 3-D analysis. This technique is applied to a 145kV self-blast-type CB and the analysis result exhibits good agreement with the experimental result.

• International journal of advanced smart convergence
• /
• 제9권4호
• /
• pp.184-191
• /
• 2020

With the emergence of the 4th Industrial Revolution, core technologies that will lead the 4th Industrial Revolution such as AI (artificial intelligence), big data, and Internet of Things (IOT) are also at the center of the topic of the general public. In particular, there is a growing trend of attempts to present future visions by discovering new models by using them for big data analysis based on data collected in a specific field, and inferring and predicting new values with the models. In order to obtain the reliability and sophistication of statistics as a result of big data analysis, it is necessary to analyze the meaning of each variable, the correlation between the variables, and multicollinearity. If the data is classified differently from the hypothesis test from the beginning, even if the analysis is performed well, unreliable results will be obtained. In other words, prior to big data analysis, it is necessary to ensure that data is well classified according to the purpose of analysis. Therefore, in this study, data is classified using a decision tree technique and a random forest technique among classification analysis, which is a machine learning technique that implements AI technology. And by evaluating the degree of classification of the data, we try to find a way to improve the classification and analysis rate of the data.

• 대한토목학회논문집
• /
• 제32권2C호
• /
• pp.79-84
• /
• 2012

말뚝에 작용하는 다양한 하중 및 현장시험결과를 통해 얻은 특정한 p-y 곡선을 적용하기에 적합한 횡방향말뚝 해석기법을 구축하였다. 구축된 해석기법을 다양한 문제에 적용하여 그 신뢰성을 검증하고 해석에서 고려한 인자들이 해석결과에 미치는 영향을 살펴보았다. 해석기법 적용시 절점간 거리가 말뚝지름의 1/2 정도일 때 해의 정확도가 높아짐을 알 수 있었다. 해석기법 적용을 통해 과다한 변위에 대해 안전한 말뚝길이 결정문제와 자립길이를 갖는 말뚝에 대하여 축력에 의한 좌굴을 검토해 보았다. 또한 옹벽 하부구조물로서의 말뚝의 말뚝머리 구속조건에 따른 해석결과를 비교하여 보았다. 개발된 해석기법은 상용 프로그램을 적용하는데 비해 해석자의 의도에 보다 적합한 유연한 해석수단이 될 것으로 생각된다.