• Journal of Mechanical Science and Technology
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• 제20권10호
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• pp.1662-1669
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• 2006

Since randomness and uncertainties of design parameters are inherent, the robust design has gained an ever increasing importance in mechanical engineering. The robustness is assessed by the measure of performance variability around mean value, which is called as standard deviation. Hence, constraints in robust optimization problem can be approached as probability constraints in reliability based optimization. Then, the FOSM (first order second moment) method or the AFOSM (advanced first order second moment) method can be used to calculate the mean values and the standard deviations of functions describing constraints and object. Among two methods, AFOSM method has some advantage over FOSM method in evaluation of probability. Nevertheless, it is difficult to obtain the mean value and the standard deviation of objective function using AFOSM method, because it requires that the mean value of function is always positive. This paper presented a special technique to overcome this weakness of AFOSM method. The mean value and the standard deviation of objective function by the proposed method are reliable as shown in examples compared with results by FOSM method.

• 설비공학논문집
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• 제22권10호
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• pp.719-726
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• 2010

In this paper, the appropriate thermal storage time of an air-conditioning system with slab thermal storage was considered by use of summer measurement values. Two standards of heat extraction rate and criterion function were established as the standard that evaluates appropriateness. When heat extraction rate was a standard, zero hour and seven hours were obtained as appropriate thermal storage time, in the case of evaluation by energy consumption and running cost individually. Also, when criterion function was a standard, the difference between energy consumption and running cost was small, it was because the weight function to room air temperature deviation was much bigger than heat extraction rate.

• Journal of the Korean Data and Information Science Society
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• 제9권2호
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• pp.305-310
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• 1998

In this paper, we introduce the conditions that the P-process has the intensity function which it is a standard form of gamma distribution. And we show that the transformed geometric Poisson process which the intensity function is a standard form of gamma distribution is a alternative sign P-process

• 한국정밀공학회지
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• 제18권7호
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• pp.46-52
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• 2001

This study describes the precision control of the torque standard machine using a self-tuning fuzzy controller. The torque standard machine should generate the accurate torque for calibrating a torque sensor. In order to reduce the relative expanded uncertainty of the torque standard machine, when a weight is hanged to the end of the torque arm for generating the torque, the sloped torque arm should be accurately controlled to the horizontal level. If the slope of the torque arm is larger from the inaccurate control, the uncertainty of the torque standard machine due to control will be larger. This applies the inaccurate torque to a torque sensor to calibrate, and the measuring error of the torque sensor generate from it. Therefore the torque arm of the torque standard machine is accurately controlled. In this paper, the self-tuning fuzzy controller was designed using a fuzzy theory, and the torque arm of the torque standard machine was accurately controlled. The control gain of the fuzzy controller, that is the membership function size of the error, the membership function size of the error change and the membership function size of the controller were determined from the self-tuning. The control results of the torque standard machine were the overshoot within 0.0076mm, the rise time within 16.70sec and the steady state error within 0.0076mm.

• 한국기록관리학회지
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• 제17권2호
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• pp.129-163
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• 2017

본 연구는, 문헌조사를 바탕으로 대한민국의 업무참조모델(BRM)인 '정부기능분류체계'의 도입에서 개발 적용에 이르기까지의 행정연혁을 통하여, 정부기능분류체계의 본래 개발목적과 의도를 밝혀내고, 현재 정부기능분류체계에서 관찰되는 문제점과의 관계를 밝힘으로써 현행에서 드러나는 정부기능분류체계의 문제에 대한 원인을 찾아보고자 하였다. 정부기능분류체계의 현황조사는 정책영역 '문화재' 영역(대기능 9개, 중기능 59개, 소기능 297개와 단위과제 1,287개)을 대상으로 중앙정부와 지방정부의 기능분류체계를 조사하였다. 그 결과, 중앙정부와 지방정부의 기능 간에 분절된 현상과 그밖에 문제점들을 발견하였고, 이를 대표하는 '문화재 지정' 등의 4가지 사례를 통해 개선모형을 제안하였다. 또한, '정부기능분류체계'의 재정비를 위하여, 업무재현성을 갖춘 업무기능의 설계, 업무기능의 일관성유지를 위한 관리와 운영에 있어서의 제도마련, 이용자의 사용촉진을 위한 교육, 지속적인 유지관리와 개선이 필요함을 제안하였다.

• 중환자간호학회지
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• 제14권1호
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• pp.50-62
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• 2021

Purpose : This study examined the effects of an integrated management program on physical function, cognitive function, and depression in patients with subacute stroke. Methods : A nonequivalent control group design was adopted. The participants were assigned to either the experimental group (n=20) or control group (n=23). The experimental group received an 8-week integrated management program and standard rehabilitation service (i.e., physical therapy and occupational therapy), while the control group received the standard rehabilitation service only. Physical function was measured as gait speed and balance ability using the Berg Balance Scale (BBS). Cognitive function was measured with neuro-behavioral cognitive status examination (NCSE), and depression was measured using the Beck Depression Inventory-II (BDI-II). Repeated measure ANOVA was used to determine changes in physical function, cognitive function, and depression over 8-weeks. Results : The interaction between group and time was significant, indicating that the experimental group showed improvement in gait speed, balance ability, cognitive function (linguistic ability, linguistic memory, reasoning), and a decrease in depression compared to the control group. Conclusion : These results indicate that the integrated management program developed herein was beneficial in restoring physical function, cognitive function, and depression in subacute stroke patients.

• Journal of the Korean Data and Information Science Society
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• 제16권4호
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• pp.815-821
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• 2005

Among the various artificial neural networks the backpropagation network (BPN) has become a standard one. One of the components in a neural network is an activating function or a transfer function of which a representative function is a sigmoid. We have discovered that by updating the slope parameter of a sigmoid function simultaneous with the weights could improve performance of a BPN.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -1
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• pp.560-563
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• 2002

This paper proposes a home control system architecture that have network configuration function. The proposed home control system architecture is implemented with partly hardware and software. For implementation of this system architecture, we developed ECONICS which is home automation controller. ECONICS consists of main board and communication modem. This communication modem supply the power line communication. The physical layer and the MAC layer software of EIA 709.1 standard protocol are implemented in communication modem. The upper layer software of EIA 709.1 standard protocol and home configuration software for home network installation, management, diagnostics, control and monitoring are implemented in main board of ECONICS. We verified the commercial feasibility of the proposed system through the home network configuration and operation. As a result, we have concluded that the proposed home control system architecture provides all the key function necessary to easily manage and control home network nodes.

• Interaction and multiscale mechanics
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• 제1권2호
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• pp.251-278
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• 2008

In this study, we investigate the discontinuous-derivative treatment at the gas-liquid interface in underwater explosion (UNDEX) problems by using the Moving Least Squares-Smoothed Particle Hydrodynamics (MLS-SPH) method, which is known as one of the particle methods suitable for problems where large deformation and inhomogeneity occur in the whole domain. Because the numerical oscillation of pressure arises from derivative discontinuity in the UNDEX analysis using the standard SPH method, the MLS shape function with Discontinuous-derivative Basis Function (DBF) that is able to represent the derivative discontinuity of field function is utilized in the MLS-SPH formulation in order to suppress the nonphysical pressure oscillation. The effectiveness of the MLS-SPH with DBF is demonstrated in comparison with the standard SPH and conventional MLS-SPH though a shock tube problem and benchmark standard problems of UNDEX of a trinitrotoluene (TNT) charge.

• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1993년도 춘계학술대회논문집
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• pp.64-68
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• 1993

The idia of modern product design is translated from the concept of functional importance as the basic function to that of emotional importance as the supplement function. In other words, the interests of the emotion in human performance side based on psychological factors of human are increased as well as the function in technical performance side based on physical factors of product. The standard emotional works for understanding the human's emotion are arranged in this paper. The standard emotional words are composed of words expressing the humaa's emotion. The adjectives adaptable to human's emotional works are collected from Korean dictionaries and arranged in the semantic differential(SD) scale. Next, the words with great marks evaluated by SD method are analyzed by factor analysis(FA) method and characterized as emotional words for understanding the human's emotion. The standard emotional words arranged in this paper are important because they are basic information for the development of product or technology as well as for the matter of emotional measurement technical development.