• 제목/요약/키워드: Machine knowledge

검색결과 643건 처리시간 0.027초

WWW를 이용한 공작기계 원격진단 시스템에 관한 연구

  • 강대천;강무진
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1997년도 춘계학술대회 논문집
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    • pp.332-336
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    • 1997
  • To order to remain competitive, a manufacturing company need to maintain the optimal condition of its manufacturing system. Machine tools as an important element of a manufacturing system comprises complex mechanical as well as electronic components. So, diagnosing the troubles of machine tools is tricky process which requires a lot of experience and knowledge. Since providing machine tool users with necessary serices at the right time is very difficult,a remote diagnosis system is to be regarded as a good alternative, with which users can diagnose and fix the machine troubles. This paper presents a method to implement a remote machine tool diagnosis system using the world wide web technology and backward reasoning expert system.

A Special Case of Three Machine Flow Shop Scheduling

  • Yang, Jaehwan
    • Industrial Engineering and Management Systems
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    • 제15권1호
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    • pp.32-40
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    • 2016
  • This paper considers a special case of a three machine flow shop scheduling problem in which operation processing time of each job is ordered such that machine 1 has the longest processing time, whereas machine 3, the shortest processing time. The objective of the problem is the minimization of the total completion time. Although the problem is simple, its complexity is yet to be established to our best knowledge. This paper first introduces the problem and presents some optimal properties of the problem. Then, it establishes several special cases in which a polynomial-time optimal solution procedure can be found. In addition, the paper proves that the recognition version of the problem is at least binary NP-complete. The complexity of the problem has been open despite its simple structure and this paper finally establishes its complexity. Finally, a simple and intuitive heuristic is developed and the tight worst case bound on relative error of 6/5 is established.

A Knowledge-Based Machine Vision System for Automated Industrial Web Inspection

  • Cho, Tai-Hoon;Jung, Young-Kee;Cho, Hyun-Chan
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제1권1호
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    • pp.13-23
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    • 2001
  • Most current machine vision systems for industrial inspection were developed with one specific task in mind. Hence, these systems are inflexible in the sense that they cannot easily be adapted to other applications. In this paper, a general vision system framework has been developed that can be easily adapted to a variety of industrial web inspection problems. The objective of this system is to automatically locate and identify \\\"defects\\\" on the surface of the material being inspected. This framework is designed to be robust, to be flexible, and to be as computationally simple as possible. To assure robustness this framework employs a combined strategy of top-down and bottom-up control, hierarchical defect models, and uncertain reasoning methods. To make this framework flexible, a modular Blackboard framework is employed. To minimize computational complexity the system incorporates a simple multi-thresholding segmentation scheme, a fuzzy logic focus of attention mechanism for scene analysis operations, and a partitioning if knowledge that allows concurrent parallel processing during recognition.cognition.

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Quantum Machine Learning: A Scientometric Assessment of Global Publications during 1999-2020

  • Dhawan, S.M.;Gupta, B.M.;Mamdapur, Ghouse Modin N.
    • International Journal of Knowledge Content Development & Technology
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    • 제11권3호
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    • pp.29-44
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    • 2021
  • The study provides a quantitative and qualitative description of global research in the domain of quantum machine learning (QML) as a way to understand the status of global research in the subject at the global, national, institutional, and individual author level. The data for the study was sourced from the Scopus database for the period 1999-2020. The study analyzed global research output (1374 publications) and global citations (22434 citations) to measure research productivity and performance on metrics. In addition, the study carried out bibliometric mapping of the literature to visually represent network relationship between key countries, institutions, authors, and significant keyword in QML research. The study finds that the USA and China lead the world ranking in QML research, accounting for 32.46% and 22.56% share respectively in the global output. The top 25 global organizations and authors lead with 35.52% and 16.59% global share respectively. The study also tracks key research areas, key global players, most significant keywords, and most productive source journals. The study observes that QML research is gradually emerging as an interdisciplinary area of research in computer science, but the body of its literature that has appeared so far is very small and insignificant even though 22 years have passed since the appearance of its first publication. Certainly, QML as a research subject at present is at a nascent stage of its development.

머신러닝 기반의 디지털 방송 프로그램 유형 분류 및 활용 방안 연구 (A Study of the Classification and Application of Digital Broadcast Program Type based on Machine Learning)

  • 윤상혁;이소현;김희웅
    • 지식경영연구
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    • 제20권3호
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    • pp.119-137
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    • 2019
  • With the recent spread of digital content, more people have been watching the digital content of TV programs on their PCs or mobile devices, rather than on TVs. With the change in such media use pattern, genres(types) of broadcast programs change in the flow of the times and viewers' trends. The programs that were broadcast on TVs have been released in digital content, and thereby people watching such content change their perception. For this reason, it is necessary to newly and differently classify genres(types) of broadcast programs on the basis of digital content, from the conventional classification of program genres(types) in broadcasting companies or relevant industries. Therefore, this study suggests a plan for newly classifying broadcast programs through using machine learning with the log data of people watching the programs in online media and for applying the new classification. This study is academically meaningful in the point that it analyzes and classifies program types on the basis of digital content. In addition, it is meaningful in the point that it makes use of the program classification algorithm developed in relevant industries, and especially suggests the strategy and plan for applying it.

쾌속조형 공정 및 장비 선정을 위한 의사결정지원 알고리즘 개발 (Development of Decision-Support Algorithms to Select RP Process and Machine)

  • 최병욱;정일용;이일랑;김태범;금영탁
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.22-25
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    • 2003
  • It is usually difficult for a single user to have all the essential knowledge on various Rapid Prototyping processes and techniques. It is therefore necessary to capture knowledge and experience of users of expert level into a decision-support system which provides quicker and more interactive way to select proper RP process and/or machine. rather than reading reports on benchmarking studies and comparing tables and graphs. In this paper two algorithms are presented, which may be used in such a decision-support system. together with its applications. The one is an extended PRES(Project Evaluation and Selection) algorithm which applies weighting factors of each attribute. The other is a LCE(Linear Confidence Equation) algorithm which is proposed to apply user's input requirements as well as weighting factors.

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새로운 유도전동기 벡터제어 기법 (A new vector control method for induction motor)

  • 변윤섭;왕종배;백종현;박현준
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2000년도 추계학술대회 논문집
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    • pp.680-687
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    • 2000
  • In this paper we present a new vector control scheme for induction motor. An exact knowledge of the rotor flux position is essential for a high-performance vector control. The position of the rotor flux is measured in the direct scheme or estimated in the indirect schemes. Since the estimation of the flux position requires a priori knowledge of the induction motor parameters, the indirect schemes are machine parameter dependent. The rotor resistance and stator resistance among the parameters change with temperature. Variations in the parameters of induction machine cause deterioration of both the steady state and dynamic operation of the induction motor drive. Several methods have been presented to minimize the consequences of parameter sensitivity in indirect scheme. In this paper new estimation scheme of rotor flux position is presented to eliminate sensitivity due to resistance change with temperature. Simulation results are used to verify the performance of the proposed vector control scheme.

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재처리를 통한 결정트리의 정확도 개선 (Improvement of Accuracy of Decision Tree By Reprocessing)

  • 이계성
    • 정보처리학회논문지B
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    • 제10B권6호
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    • pp.593-598
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    • 2003
  • 기계학습은 효율적이고 정확한 재사용을 위해 지식을 재구성한다. 본 논문은 이미 알려진 학습 객체들로부터 지식을 추출하는 '예제에 의한 개념학습 방법에 관한 연구이다. 대부분 학습 시스템은 처리와 표현에 대한 제약으로 인해 학습 결과를 새로운 객체에 적용할 때 효율성과 정확도가 기대에 못 미치는 경우가 있다. 본 논문에서는 ID3의 바이어스에 대해 조사하고, 다양한 표현 양식을 통해 보다 정확하고 학습적으로 이해하기 쉬운 분류 방법을 제안한다.

공간전압 벡터제어를 통한 유도전동기의 새로운 벡터제어성능연구 (A new vector control performance for induction motor with SVPWM)

  • 변윤섭;장동욱
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 D
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    • pp.2246-2248
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    • 2001
  • This paper presents a new vector control scheme for induction motor. An exact knowledge of the rotor flux position is essential for a high-performance vector control. The position of the rotor flux is measured in the direct schemes and estimated in the indirect schemes. Since the estimation of the flux position requires a priori knowledge of the induction motor parameters, the indirect schemes are machine parameter dependent. The rotor and stator resistance among the parameters change with temperature. Variations in the parameters of induction machine cause deterioration of both the steady state and dynamic operation of the induction motor drive. Several methods have presented to minimize the consequences of parameter sensitivity in indirect scheme. In this paper, new estimation scheme of rotor flux position is presented to eliminate sensitivity due to variation in the resistance. The simulation is executed to verify the proposed vector control performance and to compare its performance with that of indirect and direct vector control.

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Application of transfer learning for streamflow prediction by using attention-based Informer algorithm

  • Fatemeh Ghobadi;Doosun Kang
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2023년도 학술발표회
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    • pp.165-165
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    • 2023
  • Streamflow prediction is a critical task in water resources management and essential for planning and decision-making purposes. However, the streamflow prediction is challenging due to the complexity and non-linear nature of hydrological processes. The transfer learning is a powerful technique that enables a model to transfer knowledge from a source domain to a target domain, improving model performance with limited data in the target domain. In this study, we apply the transfer learning using the Informer model, which is a state-of-the-art deep learning model for streamflow prediction. The model was trained on a large-scale hydrological dataset in the source basin and then fine-tuned using a smaller dataset available in the target basin to predict the streamflow in the target basin. The results demonstrate that transfer learning using the Informer model significantly outperforms the traditional machine learning models and even other deep learning models for streamflow prediction, especially when the target domain has limited data. Moreover, the results indicate the effectiveness of streamflow prediction when knowledge transfer is used to improve the generalizability of hydrologic models in data-sparse regions.

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