• 제목/요약/키워드: evaluation function

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An efficient simulation method for reliability analysis of systems with expensive-to-evaluate performance functions

  • Azar, Bahman Farahmand;Hadidi, Ali;Rafiee, Amin
    • Structural Engineering and Mechanics
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    • 제55권5호
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    • pp.979-999
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    • 2015
  • This paper proposes a novel reliability analysis method which computes reliability index, most probable point and probability of failure of uncertain systems more efficiently and accurately with compared to Monte Carlo, first-order reliability and response surface methods. It consists of Initial and Simulation steps. In Initial step, a number of space-filling designs are selected throughout the variables space, and then in Simulation step, performances of most of samples are estimated via interpolation using the space-filling designs, and only for a small number of the samples actual performance function is used for evaluation. In better words, doing so, we use a simple interpolation function called "reduced" function instead of the actual expensive-to-evaluate performance function of the system to evaluate most of samples. By using such a reduced function, total number of evaluations of actual performance is significantly reduced; hence, the method can be called Reduced Function Evaluations method. Reliabilities of six examples including series and parallel systems with multiple failure modes with truncated and/or non-truncated random variables are analyzed to demonstrate efficiency, accuracy and robustness of proposed method. In addition, a reliability-based design optimization algorithm is proposed and an example is solved to show its good performance.

Gompertz 소프트웨어 비용 추정 모델 (A Gompertz Model for Software Cost Estimation)

  • 이상운
    • 정보처리학회논문지D
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    • 제15D권2호
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    • pp.207-212
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    • 2008
  • 본 논문은 소프트웨어 비용추정 모델의 적합성을 평가하고, 가장 적합한 모델을 제시하였다. 먼저, 해당 모델의 함수를 변수변환시켜 선형식으로 만든다. 다음으로 실제 개발 소프트웨어의 비용 데이터가 모델의 선형식에 얼마나 적합한지로 모델의 성능을 평가한다. 모델 성능평가에는 절대오차 대신 상대오차 개념인 MMRE를 적용하였다. 기존의 소프트웨어 비용추정 모델은 Weibull, Gamma와 Rayleigh 함수를 따르고 있다. 본 논문에서는 성장곡선의 일종인 Gompertz 곡선 모델을 제안하였다. 추가로 다른 성장곡선들도 적합성을 검증하였다. 모델 성능평가 결과 Gompertz 성장곡선이 소프트웨어 비용추정 모델로 가장 적합한 성능을 보였다.

비오톱 연계망 구축을 위한 서식공간 평가 -대구시 수성구를 중심으로- (An Evaluation of Biotope to Develop Its Green Network -in the Case of Susong-Gu in Daegu Metropolitan Area-)

  • 나정화;사공정희;류연수
    • 한국조경학회지
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    • 제29권1호
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    • pp.67-79
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    • 2001
  • The purpose of this research is to evaluate the biotope value in a metropolitan area after constructing the biotope evaluation model to develop biotope networking in the light of ecological landscape planning. In addition this study is to provide a basic frame of constructing the biotope networking system in the future with the evaluation results. The scope of this research is limited to high density residential area including some part of the forest adjacent to urban boundary. The results of the classified biotope in the research area have been turned out to be 24 patterns. According to the result of estimated nature value having the forth grade, three were forests combined with urban natural parks, schools near forests, and grasslands. There is a little place having first grade. We an deduce this fact that we have surveyed biotopes, having the minimum nature value and wider than children's park. As for the result of evaluated the structure, there were the forests of Seong-Dong, Meaho-Dong, and Kumho river, which is the forth grade. As for the evaluation of connection-function, the followings area were evaluated as the third grade-linear biotopes having highly valued and sustainable similarity - Seoul-Pusan Railroad, Dong-Daegu St., Kumho river, river basins. Bum대 park and a botanic park near Suesung lake, As for the evaluated the buffer-function, higly valued production biotopes, existing at a transition belt between he residential density areas, are Sawol-Dong, Meaho-Dong and Kumho river. When each of the indexes was evaluated, the core of the biotop contained most of natural biotopes. Large artificial biotopes were evaluated as an important biotopes, while small artificial biotopes were classified as a dot biotope. The future research on the concrete biotope networking construction, based upon performed evaluation in this research, should be conducted.

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TEM 관련 이론해설 (2): Fourier 변환 (Fourier Transformations)

  • 이확주
    • Applied Microscopy
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    • 제32권3호
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    • pp.195-204
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    • 2002
  • TEM 이론의 기초가 되는 델타함수, 콘볼루션 적분, 퓨리에 변환에 관한 개념을 소개하고 이에 대한 응용으로 슬릿함수, 현저한 폭을 갖는 2개의 슬릿, 유한 크기의 파동 train, 좁은 슬릿의 주기적인 배열, 임의의 주기 함수, diffraction grating, 회절 격자, 그리고 gaussian 함수에서의 퓨리에 변환에 관한 수학적인 방법의 적용을 소개하였다.

손 기능 훈련이 손의 기민성에 미치는 영향 (The Effect of Hand Function Training on Hand Dexterity)

  • 장철;이제영;송민옥
    • 대한통합의학회지
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    • 제3권4호
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    • pp.11-21
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    • 2015
  • Purpose : The purpose of this study was to provide the material about the treatment effect of hand function training and writing training being performed as a part of treatment to improve the function of the non-dominant hand of the patients whose dominant hand is damaged and thus need to improve their non-dominant hand's function. Method : During one month of November, 2013, this study randomly chose five study subjects for hand function training, five for writing training, and ten of control group from 20 normal male and female adults going to K Univ. in Busan. All study subjects fully understood all of the training course, agreed to take the test in this study, and volunteered to participate in the test. Each training was performed five times for two weeks, 30 minutes each time. For measurement, Purdue pegboard was used to look into the change of hand dexterity. To investigate an improvement in hand function through hand function training and writing training, this study conducted early evaluation before training, interim evaluation, and final evaluation. Result : First, according to the comparison of dominant hand dexterity by group and by method during a training period, the groups of hand function training and of writing training improved dominant hand dexterity more than the control group. Secondly, according to the comparison of non-dominant hand dexterity by group during a training period, the groups of hand function training and of writing training improved dexterity more than the control group. According to the comparison of non-dominant hand dexterity by method during a training period, there was no big difference in dexterity between the groups of hand function training and of writing training and the control group. But, the group of hand function training showed a further improvement. Thirdly, according to the comparison of both-hand dexterity by group and by method during a training period, the groups of hand function training and of writing training improved both-hand dexterity more than the control group. Fourthly, according to the comparison of both-hand handling ability by group and by method during a training period, the groups of hand function training and of writing training improved both-hand handling ability more than the control group. Conclusion : Given the study result, it is considered that hand function training and writing training help brain damaged patients improve their hand function for their daily activity. And it will be meaningful to research brain damaged patients' motor skills after their brain damage, and the patients who have low abilities of visual perception and cognition. In the future, it will be necessary to secure more study subjects and perform systematic training during a sufficient test period.

감각조절장애 아동을 위한 가정 프로그램의 효과 (The Effect of Home-based Program For Children With Sensory Modulation Disorder)

  • 이성아;김지연;조은희;박경영
    • 대한감각통합치료학회지
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    • 제1권1호
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    • pp.25-37
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    • 2003
  • Objective : To explore the effectiveness of sensory integration program of home-based outcomes in child with sensory modulation disorder. Methods : This study used the simple case study. The subjects were three children diagnosed as developmentally delayed who 14 month and 26 month males and a 15 month female. After initial evaluation, parents were educated on sensory diet and Wilbarger protocol method for 30 minutes twice for home-based treatment and asked to make out daily treatment planning. To measure improvement of children, we used for the Denver Developmental Screening Test II(DDST II), Wee Functional Independence Measure(WeeFIM), hand function, functional ability, oral motor function, Sensory Profile(Dunn, 1999). Results : After the home-based program, the scored of the Denver Developmental Screening Test II(DDST II), Wee Functional Independence Measure(WeeFIM), hand function, functional ability, oral motor function, Sensory Profile(Dunn, 1999) were higher rather than initial evaluation after the home-based program. Conclusion : The home-based program is effective for children with sensory modulation disorder but parents had to be educated by therapist specific evaluation and treatment in sensory integration.

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GIS와 설문분석에 의한 강원대 학술림의 비목재생산기능 평가 (Evaluation of Non-Timber Forest Functions in the Research Forest of Kangwon National University Using GIS and Questionnaire Analysis)

  • 최상현;김진국;우종춘
    • Journal of Forest and Environmental Science
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    • 제29권1호
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    • pp.99-108
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    • 2013
  • This study was conducted to evaluate the non-timber forest functions of the Research Forest area of Kangwon National University. In this study, forest recreation function was investigated through survey method answered by forest management experts. The evaluation factors for forest recreation function were separated into external and internal factors. Each factor was classified into intermediate element and detailed element. Therefore in this study, the evaluation factors of forest recreation function were divided into two groups which are the potential of external factors and the suitability of internal factors. Potential of the external factors were divided into accessibility, location, landscape and induction factors while the suitability of internal factor was divided into stand structure, forest structure and human impact. The priority of the potential of external factors was in order that location, accessibility, induction factors and landscape. The most important factors for the location, accessibility, induction and landscape factors are based on regional characteristics.

Factors affecting real-time evaluation of muscle function in smart rehab systems

  • Hyunwoo Joe;Hyunsuk Kim;Seung-Jun Lee;Tae Sung Park;Myung-Jun Shin;Lee Hooman;Daesub Yoon;Woojin Kim
    • ETRI Journal
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    • 제45권4호
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    • pp.603-614
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    • 2023
  • Advancements in remote medical technologies and smart devices have led to expectations of contactless rehabilitation. Conventionally, rehabilitation requires clinicians to perform routine muscle function assessments with patients. However, assessment results are difficult to cross-reference owing to the lack of a gold standard. Thus, the application of remote smart rehabilitation systems is significantly hindered. This study analyzes the factors affecting the real-time evaluation of muscle function based on biometric sensor data so that we can provide a basis for a remote system. We acquired real clinical stroke patient data to identify the meaningful features associated with normal and abnormal musculature. We provide a system based on these emerging features that assesses muscle functionality in real time via streamed biometric signal data. A system view based on the amount of data, data processing speed, and feature proportions is provided to support the production of a rudimentary remote smart rehabilitation system.

차량 고급감 향상을 위한 흡배기계 음질지수 개발 (A Development of Sound Quality Index of an Intake and Exhaust System for High Quality Improvement of Luxury Vehicles)

  • 이종규;조덕형;서대원;임윤수;원광민
    • 한국소음진동공학회논문집
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    • 제22권3호
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    • pp.234-243
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    • 2012
  • In this paper, a sound quality indices for the evaluation of vehicle intake and exhaust noise were developed through a correlation analysis of objective measurement data and subjective evaluation data. At first, intake and exhaust orifice noise were measured at the wide-open throttle sweep condition. And then, acoustic transfer function between intake orifice noise and interior noise at the steady state condition was measured. Also, acoustic transfer function for exhaust system was measured as the same method. Simultaneously, subjective evaluation was carried out by the paired comparison and semantic differential method by 27 engineers. Next, the correlation analysis between the psycho-acoustic parameters derived from the measured data and the subjective evaluation was performed. The most critical factor was determined and the corresponding sound quality index for the intake and exhaust noise was obtained from the multiple factor regression method. At last, the effectiveness of the proposed index was investigated.

도심하천 복원에 따른 하천유지유량 산정 연구 (A Study for the Calculation of Instream Flow in the Rehabilitation of Urban stream)

  • 최계운;장연규;한만신
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2004년도 학술발표회
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    • pp.448-452
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    • 2004
  • Instream flow is necessary to manage the basic function of the rivers. The evaluation method of instream flow in a big river has been studied widely. However, the study in a urban hasn't researched. In theses days the environmental function of a river becomes very important. The evaluation method and secure of instream flow are basic conditions to perform it. Especially view of stream, recreation, protection of ecology are highly demanded In a urban according to the multipurpose of river spaces. In this paper the evaluation methods of instream flow were compared and investigated with many papers. This paper presents a proper evaluation procedure of instream flow in a urban stream through comparison and examination. According to the demanded hydraulic conditions the method can be considered the environmental function depend on the purpose of river restoration. The relationship of the coefficient of roughness and the slope of the river bed were examinated in order to estimate the minimum instream flow corresponding to proper Hydraulic conditions. Also calculate the instream flow of Sueng-gi stream in In-cheon.

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