• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.320-326
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• 2002

Distribution system loss minimization re-configuration is 0-1 planning problem, and the number of combinations requiring searches is extremely large when dealing with typical system scales. For this reason, the application of a genetic algorithm (GA) seems attactive to solve this problem. Although Genetic algorithms are a type of random number search method, they incorporate a multi-point search feature and are therefore superior to one-point search techniques. The efficiency of GAs for solving large combinational problem has received wide attention. Further, parallel searching can be performed and the optimal solution is more easily reached. In this paper, for improving GA convergence characteristics in the distribution system loss minimization re-configeration problem, a chromosome "Limited Life" concept is intro duced. Briefly, considering the population homogenization and genetic drift problems, natural selection is achieved by providing this new concept, in addition to natural selection by fitness. This is possible because individuals in a population have an age value. Simulations were carried out using a model system to check this method's validity.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제6권3호
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• pp.264-269
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• 2006

This paper presents the strategy for searching a hidden object in an unknown area for using by multiple distributed autonomous robotic systems (DARS). To search the target in Markovian space, DARS should recognize th ε ir surrounding at where they are located and generate some rules to act upon by themselves. First of all, DARS obtain 6-distances from itself to environment by infrared sensor which are hexagonally allocated around itself. Second, it calculates 6-areas with those distances then take an action, i.e., turn and move toward where the widest space will be guaranteed. After the action is taken, the value of Q will be updated by relative formula at the state. We set up an experimental environment with five small mobile robots, obstacles, and a target object, and tried to research for a target object while navigating in a un known hallway where some obstacles were placed. In the end of this paper, we present the results of three algorithms - a random search, an area-based action making process to determine the next action of the robot and hexagon-based Q-learning to enhance the area-based action making process.

• Asian Pacific Journal of Cancer Prevention
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• 제13권8호
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• pp.4097-4100
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• 2012

Background/Aims: Diabetes mellitus (DM) is widely considered to be associated with risk of cancer, but studies investigating the association between DM and prostate cancer in Asian countries have reported inconsistent findings. We examined this association by conducting a detailed meta-analysis of studies published on the subject. Methods: Cohort or case-control studies were identified by searching Pubmed, Embase and Wanfang databases through May 30, 2012. Pooled relative risk (RR) with its corresponding 95% confidence interval (95% CI) were calculated using the random-effects model. Subgroup analyses were performed by the study type. Results: Finally, we identified 7 studies (four cohort studies and three case-control studies) with a total of 1,751,274 subjects from Asians. DM was associated with an increased risk of prostate cancer in Asians (unadjusted RR= 2.82, 95% CI 1.73.4.58, P < 0.001; adjusted RR= 1.31, 95% CI 1.12.1.54, P = 0.001). Subgroup analyses by study design further confirmed an obvious association. Conclusion: Findings from this meta-analysis strongly support that diabetes is associated with an increased risk of prostate cancer in Asians.

• 제어로봇시스템학회논문지
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• 제10권1호
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• pp.47-53
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• 2004

An electro-hydraulic manipulator using hydraulic actuators has many nonlinear elements, and its parameter fluctuations are greater than those of an electrically driven manipulator. So it is quite difficult to obtain stable control performance. We have applied a disturbance estimation and compensation type robust control to all the axes in a 6-link electro-hydraulic manipulator. It was confirmed that the performance of trajectory tracking and attitude regulating was greatly improved by the disturbance observer. For autonomous assembly tasks, it is said that compliance control is one of the most popular methods in contact task. We have proposed a compliance control based on the position control by a disturbance observer for our manipulator system. To realize more stable contact work, the states in the compliance loop are feedbacked, where not only displacement but also the velocity and acceleration are considered. We have also applied this compliance control to the Peg-in-Hole insertion task and proposed new methods of (1)rotating of the end-effector periodically in order to reduce the friction force, (2)random searching for the center of a hole and (3)trajectory modification to reduce the impact force. As a result of these new methods, it could be experimentally confirmed that the Peg-in-Hole insertion task with a clearance of 0.007 [mm] could be achieved.

• 한국지반공학회논문집
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• 제18권6호
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• pp.117-127
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• 2002

사면의 파괴면 형태를 간단한 비선형 함수로 모델링하여 해석하는 결정론적인 사면안정 해석은 지층의 복합 특성과 불연속적인 특성을 효과적으로 반영하지 못하는 단점이 있다. 따라서, 본 연구에서는 결정론적인 방법 보다 지층의 제반조건들을 다양하게 반영할 수 있는 임의 탐색기법인 유전자 알고리즘을 이용한 사면안정 해석 방법을 제시하였다. 제시된 방법의 적합성을 확인하기 위해 단일지층 및 복합지층을 대상으로 하여 제안된 방법과 결정론적인 방법을 비교.검토하였으며, 검토결과 유전자 알고리즘을 이용한 사면안정해석 방법의 적용성을 검증할 수 있었다. 또한 제시된 사면안정 해석 방법에 강우강도에 따른 지하수위의 변화 예측모델을 적용하여 보다 합리적인 사면안정 해석 방법을 제시하였다.

• 대한물리치료과학회지
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• 제27권2호
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• pp.36-47
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• 2020

Background: This study purposed to provide meaningful information for the accumulation of knowledge on coordinative locomotor training in patients with stroke. Design: Meta-analysis. Methods: This study collected articles which the coordinative locomotor training in patients with stroke. For systematic meta-analysis, 6 articles were finally selected after searching based on the PICOSD criteria. This meta-analysis was conducted according to PRISMA guidelines. Randomized controlled trials were included and the risk of bias was evaluated for each study. Pooled standardized mean differences were calculated using a random effects model. To extract the effect size of each study, the R 3.5.3 software was used. Results: The meta-analysis showed that a total effects size was 1.23 indicating that coordinative locomotor training for patients with stroke had a maximum effect size. Conclusion: A meta-analysis is warranted for further research to determine the effects of coordinative locomotor training in patients with stroke on muscle strength, walking and range of motion.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1996년도 춘계학술대회 논문집
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• pp.24-29
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• 1996

The seniconductor, which is precision product, requires many inspection processes. The surface conditions of the semiconductor chip effect on the functions of the semiconductors. The defects of the chip surface is crack or void. Because general inspection method requires many inspection processes, the inspection system which searches immediately and preciselythe defects of the semiconductor chip surface. We propose the inspection method by using the computer vision system. This study presents an image processing algorithm for inspecting the surface defects(crack, void)of the semiconductor test samples. The proposed image processing algorithm aims to reduce inspection time, and to analyze those experienced operator. This paper regards the chip surface as random texture, and deals with the image modeling of randon texture image for searching the surface defects. For texture modeling, we consider the relation of a pixel and neighborhood pixels as noncasul model and extract the statistical characteristics from the radom texture field by using the 2D AR model(Aut oregressive). This paper regards on image as the output of linear system, and considers the fidelity or intelligibility criteria for measuring the quality of an image or the performance of the processing techinque. This study utilizes the variance of prediction error which is computed by substituting the gary level of pixel of another texture field into the two dimensional AR(autoregressive model)model fitted to the texture field, estimate the parameter us-ing the PAA(parameter adaptation algorithm) and design the defect detection filter. Later, we next try to study the defect detection search algorithm.

• International Journal of Knowledge Content Development & Technology
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• 제10권3호
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• pp.51-68
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• 2020

The library provides its services to satisfy the user's approach. Naturally, the development of library services may determine by considering the satisfaction of users. It traces users' perceptions regarding subject access highlighting problems in the retrieval of Bengali documents by subject. This study has designed to assess users' attitudes towards the retrievals of Bengali documents in OPAC through subject headings. For a collection of data, a representative sample has drawn from a large and heterogeneous population consisting of users in university libraries of West Bengal using a stratified sampling technique. Subsequently, under each of the universities, users' community was stratified into students, research scholars, and faculty members. Under each stratum, the sample selected on a random basis. The users met personally to collect relevant data, while they came to the library and went on to search OPAC. A structured schedule, prepared for the purpose, was presented before library users and consequently, interviews and interpretations recorded systematically. In this manner, several factors have identified concerning subject searching and retrieval performance for Bengali documents. This study explores the access using subject headings in multilingual information retrieval systems. Moreover, the suitability of subject headings for retrieval of Bengali resources has ascertained from the users' point of view. The findings demand standard principles and rules for the construction of Bengali subject headings to maintain uniformity and consistency.

• 지역사회간호학회지
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• 제29권4호
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• pp.510-519
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• 2018

Purpose: The purpose of this meta-analysis isto identify social psychological factors related to quality of life and estimate the effect sizes of the factors among patients with strokes. Methods: Thirteen studies with a total of 1,814 patients published from the earliest records to January 8, 2017 were selected through a systematic process of searching the literature, and evaluated against influencing factors of quality of life and their effect sizes. Pooled effect sizes were calculated using the random effect model. Meta-analysis was conducted by R software. Results: The following influencing factors had a strong association with quality of life with stroke: depression (r=-.50; 95% CI: -0.63~-0.46), activities of daily living (r=.46; 95% CI: 0.35~0.56), and social support (r=.40; 95% CI: 0.24~0.53). Conclusion: The findings confirm that depression, activities of daily living and social support are associated with quality of life among patients with stroke survivors. We recommend that any intervention program to improve the quality of life with stroke patients consider addressing these modifiable influencing factors.

• International Journal of Computer Science & Network Security
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• 제21권7호
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• pp.267-272
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• 2021

The current study aimed at measuring the rate of loss in search results of the actual number of publications in journals indexed by Web of Science when not using the accurate official authority name as indicated by the Ministry of Education. Conducting a search using the authority name does not always yield complete results of all existing publications. Researchers in Saudi universities tend to use up to 10 different random names of universities when searching. This interesting fact has prompted the authors of this paper to conduct a study on the search results of 30 Saudi universities using the authority name as indicated by the Ministry of Education. The statistical analyses revealed that there is a high tendency for the wrong use of authority names. Results show that 8 universities were not found in the search results. Furthermore, other universities are losing between 10 and 30% of search results that reflect the actual number of publications. Consequently, the rank of each university, as well as the general rank of Saudi universities in the Web of Science, will be affected.