• 제목/요약/키워드: fuzzy evaluation model

Search Result 289, Processing Time 0.025 seconds

Estimation of residual stress in dissimilar metals welding using deep fuzzy neural networks with rule-dropout

  • Ji Hun Park;Man Gyun Na
    • Nuclear Engineering and Technology
    • /
    • v.56 no.10
    • /
    • pp.4149-4157
    • /
    • 2024
  • Welding processes are used to connect several components in nuclear power plants. These welding processes can induce residual stress in welding joints, which has been identified as a significant factor in primary water stress corrosion cracking. Consequently, the assessment of welding residual stress plays a crucial role in determining the structural integrity of welded joints. In this study, a deep fuzzy neural networks (DFNN) with a rule-dropout method, which is an artificial intelligence (AI) method, was used to predict the residual stress of dissimilar metal welding. ABAQUS, a finite element analysis program, was used as the data collection tool to develop the AI model, and 6300 data instances were collected under 150 analysis conditions. A rule-dropout method and genetic algorithm were used to optimize the estimation performance of the DFNN model. DFNN with the rule-dropout model was compared to a deep neural network method, known as a general deep learning method, to evaluate the estimation performance of DFNN. In addition, a fuzzy neural network method and a cascaded support vector regression method conducted in previous studies were compared. Consequently, the estimation performance of the DFNN with the rule-dropout model was better than those of the comparison methods. The welding residual stress estimation results of this study are expected to contribute to the evaluation of the structural integrity of welded joints.

An Evaluation of Business Performance for Water Transportation Company Groups Using the Integrated Fuzzy AHP-PROMETHEE Method (통합 Fuzzy AHP-PROMETHEE법을 이용한 수상운송기업군의 경영성과 평가)

  • Jang, Woon-Jae
    • Journal of Navigation and Port Research
    • /
    • v.44 no.4
    • /
    • pp.319-325
    • /
    • 2020
  • The Korean government has been pursuing many supporting programs to enhance the competition of water transportation companies in recent years. To implement the policies effectively, which needs its monitering and evaluates about their business performance. The purpose of this study was to evaluate the business performance of water transportation company groups and determine the outranking between the groups using the Integrated Fuzzy AHP-PROMETHEE.. To achieve this purpose, first, the companies were classified into seven alternative company groups and the criteria for their evaluation was extracted Second, the weights of the criteria, by maritime and port expert survey, were calculated using the Fuzzy AHP. This paper, finally, determined the total priority orders of their company groups as the link Fuzzy PROMETHEE II with weights of the criteria and the local priority orders between them using the Fuzzy PROMETHEE I. In the proposal for this model, thus was collected four criteria such as growth ability, beneficial ability, technical ability, and productive ability. Through the result of this evaluation, the other marine transportation services group was determined as the highest outranking but the inland passenger & cargo transportation services group was lowest. Thus, the developing plan of the productive ability for the other marine transportation services group should be reviewed to continue its good performance, and all off the criteria for the inland passenger & cargo transportation services group to raise the performance should be reviewed.

Fuzzy Logic in Nuclear Safety Issues

  • Ruan, Da
    • Journal of the Korean Institute of Intelligent Systems
    • /
    • v.7 no.1
    • /
    • pp.34-44
    • /
    • 1997
  • The Belgian Nuclear Research Centre(SCK${\cdot}$CEN) has been a pioneer of the peaceful uses of nuclear energy after over forty years of existence. Recently, SCK${\cdot}$CEN's financial support of doctoral and postdoctoral research in close collaboration with universities has been a vital ingredient for securing a quality profile committed to the pursuit of execllence. FLINS, Fuzzy Logic and Intelligent technologies in Nuclear Science, was initially built within one of the postdoctoral research project at SCK${\cdot}$CEN. Among SCK${\cdot}$CEN's activities which will have an important impact on its scientific future, the application of fuzzy logic and intelligent technologies in nuclear science and engineering opens new domains in radiation protection, safety assessment, human reliability, nuclear reactor control, waste and disposal, etc. In this paper, we review the available literature on fuzzy logic in nuclear applications. We then present the initiative of R&D on fuzzy logic applications at SCK${\cdot}$CEN, namely, (1) safety control for a nuclear reactor, and (2) a safety evaluation model for nuclear transmission lines. By these two examples of nuclear applications, we illustrate the potential use of fuzzy logic in nuclear safety issues.

  • PDF

A fuzzy ART Approach for IS Personnel Selection and Evaluation (정보시스템 인력의 선발 및 평가를 위한 퍼지 ART 접근방법)

  • Uprety, Sudan Prasad;Jeong, Seung Ryul
    • Journal of Internet Computing and Services
    • /
    • v.14 no.6
    • /
    • pp.25-32
    • /
    • 2013
  • Due to increasing competition of globalization and fast technological improvements the appropriate method for evaluating and selecting IS-personnel is one of the key factors for an organization's success. Personnel selection is a multi-criteria decision-making (MCDM) problem which consists of both qualitative and quantitative metrics. Although many articles have discussed various knowledge and skills IS personnel should possess, no specific model for IS personnel selection and evaluation, to our knowledge, has been published up to now. After reviewing the IS personnel's important characteristics, we propose an approach for categorizing the IS personnel based on their skills, ability, and knowledge during evaluation and selection process. Our proposed approach is derived from a model of neural network algorithm. We have adapted and implemented the fuzzy ART algorithm with Jaccard choice function. The result of an illustrative numerical example is proposed to demonstrate the easiness and effectiveness of our approach.

A Study on the Preparation of Jeung-pyun by Application of the Fuzzy Theory (증편제조를 위한 퍼지 이론 적용에 관한 연구)

  • 권경순
    • The Korean Journal of Food And Nutrition
    • /
    • v.15 no.3
    • /
    • pp.228-234
    • /
    • 2002
  • In this paper, we proposed a preparation of Jeung- pyun (Korean fermented steamed rice cake with sour taste and spongy texture) using fuzzy theory. Before this preparation was introduced, it thoroughly analyzed the existing data of Jeung-pyun preparation with sensory evaluation and instrumental measurement. It defined a membership auction of Fuzzy set by analyzed three sorts of data on Jeung-pyun. And it established the Fuzzy model using the quantity of materials as input, such as rice, flour, wheat flour and fermentation time, and the sensory test scores as output, such as grain, softness, sourness, chewiness, overall quality, pH value and volume, respectively. We got the results that the Fuzzy model was accord with the conventional method with sensory evaluation. And the validity of this method is shown through the computer simulation of the test data. Therefore, the proposed method by Fuzzy model will apply to make Jeung-pyun without sensory evaluation. This study will contribute to develop standard preparation for korean foods and expert system of preparation using computer system.

Fuzzy Measure-based Subset Interactive Models for Interactive Systems. (퍼지 측도를 이용한 상호 작용 시스템의 모델)

  • 권순학;스게노미치오
    • Journal of the Korean Institute of Intelligent Systems
    • /
    • v.7 no.4
    • /
    • pp.82-92
    • /
    • 1997
  • In this paper, a fuzzy measure and integral-based model fnr interactive systems is proposed. The processes of model identification consists of the following three steps : (i) structure identification (ii) parameter identification and (iii) selection of an optimal model. An algorithm for the model structure identification using the well-known genetic algorithm ((;A) with a modified selection operator is proposed. A method for the identification of par;imetcrs corresponding to fuzzy measures is presented. A statistical model selection criterion is used for the selection of an optimal model among the candidates. Finally, experimental results obtained hy applying the proposed model to the subjective evaluation data set and the well-known time series data are presented to show the validity of the proposed model.

  • PDF

Identification and risk management related to construction projects

  • Boughaba, Amina;Bouabaz, Mohamed
    • Advances in Computational Design
    • /
    • v.5 no.4
    • /
    • pp.445-465
    • /
    • 2020
  • This paper presents a study conducted with the aim of developing a model of tendering based on a technique of artificial intelligence by managing and controlling the factors of success or failure of construction projects through the evaluation of the process of invitation to tender. Aiming to solve this problem, analysis of the current environment based on SWOT (Strengths, Weaknesses, Opportunities, and Threats) is first carried out. Analysis was evaluated through a case study of the construction projects in Algeria, to bring about the internal and external factors which affect the process of invitation to tender related to the construction projects. This paper aims to develop a mean to identify threats-opportunities and strength-weaknesses related to the environment of various national construction projects, leading to the decision on whether to continue the project or not. Following a SWOT analysis, novel artificial intelligence models in forecasting the project status are proposed. The basic principal consists in interconnecting the different factors to model this phenomenon. An artificial neural network model is first proposed, followed by a model based on fuzzy logic. A third model resulting from the combination of the two previous ones is developed as a hybrid model. A simulation study is carried out to assess performance of the three models showing that the hybrid model is better suited in forecasting the construction project status than RNN (recurrent neural network) and FL (fuzzy logic) models.

A study on location selection of total circulation complex using fuzzy theory (퍼지이론을 이용한 종합유통단지 입지 선정에 관한 연구)

  • Oh, Sun-Il;Yoon, Ho-Bin;Kang, Kyung-Sik
    • Journal of the Korea Safety Management & Science
    • /
    • v.10 no.1
    • /
    • pp.91-105
    • /
    • 2008
  • Nowadays, circulation industry is taking charge of important role in improvement of competitive power on the manufacturing industry and public welfare increase of consumer, price stabilization, employment creation and so on. A lot of research have been progressing for formation of total circulation complex, but decision making for selection of location on some facility is only calculated the optimum value when correct data values are inserted. However, a lot of decision making is accomplished in situation that have little knowledge of objective and constraints and as real world is also evaluated inclusive of analyst's subjectivity about variable, indefinite and fuzzy part, so it is decreasing a reliability on evaluation result and complicating objective evaluation on various effect and negative impact. Accordingly, from under like this situation, this study is to develop location decision model of circulation complex using fuzzy theory from the intention for the most reasonable decision making in fuzzy situation based on decision making problem on conventional location and size decision that did to be satisfactory constraints necessarily.

Design and Performance Evaluation of Controller for Unstable Motion of Underwater Vehicle after Water Entry (수중운동체 입수 초기의 불안정 거동에 대한 제어기 설계 및 성능평가)

  • Park, Yeong-Il;Ryu, Dong-Ki;Kim, Sam-Soo;Lee, Man-Hyung
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.16 no.6
    • /
    • pp.166-175
    • /
    • 1999
  • This paper describes a design and performance evaluation of robust controller which overrides unstable motion and pulls out quickly after water entry of underwater vehicle dropped from aircraft or surface ship. We use 6-DOF equation for model of motions and assume parameter uncertainty to reflect the difference of real motion from modelled motion equation. we represent a nonlinear system with uncertainty as Takagi and Sugeno's(T-S) fuzzy models and design controller stabilizing them. The fuzzy controller utilizes the concept of so-called parallel distributed compensation (PDC). Finally, we confirm stability and performance of the controller through computer simulation and hardware in the loop simulation (HILS).

  • PDF

Computer Aided Diagnosis System based on Performance Evaluation Agent Model

  • Rhee, Hyun-Sook
    • Journal of the Korea Society of Computer and Information
    • /
    • v.21 no.1
    • /
    • pp.9-16
    • /
    • 2016
  • In this paper, we present a performance evaluation agent based on fuzzy cluster analysis and validity measures. The proposed agent is consists of three modules, fuzzy cluster analyzer, performance evaluation measures, and feature ranking algorithm for feature selection step in CAD system. Feature selection is an important step commonly used to create more accurate system to help human experts. Through this agent, we get the feature ranking on the dataset of mass and calcification lesions extracted from the public real world mammogram database DDSM. Also we design a CAD system incorporating the agent and apply five different feature combinations to the system. Experimental results proposed approach has higher classification accuracy and shows the feasibility as a diagnosis supporting tool.