• 제목/요약/키워드: paper machine

검색결과 9,778건 처리시간 0.039초

Systematic Study of Paper Breaks in Papermaking Process Using Fracture Mechanics - (1) Evaluation of fracture Toughness in Wet State

  • Seo, Yung-B;Roh, You-Sun
    • 펄프종이기술
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    • 제33권5호
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    • pp.37-44
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    • 2001
  • Fracture toughness was considered as one of the good estimates of the paper break tendency of paper web in the press room. Paper break on the paper machine is caused by many factors such as paper machine irregular vibrations, impurities in the fiber furnish, shives, and so on. On the paper machine, the solid content of paper web is changing very rapidly from less than 1% to over 95%. We tried to measure the fracture toughness of paper web at different solid contents for providing the fundamental knowledge of paper break. Stretches of wet web were also measured and compared to the fracture toughness changes. Four different fiber furnishes (SwBKP, HwBKP, ONP, and OCC) were refined to different degrees, and at different solid contents (40%, 60%, 80% and 95%), their fracture toughnesses were measured. Two fracture toughness measurement methods (essential work of fracture and Tryding's load-widening method) were used, and we found they gave identical results. The stretch curves of the wet webs against the axis of solid contents were very similar to the fracture toughness curves of those.

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방향성을 고려한 일반화된 공작기계의 입체오차 모델링 (A Generalized Volumetric Error Modeling Considering Backlash in Machine Tools)

  • 안경기;조동우
    • 한국정밀공학회지
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    • 제19권4호
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    • pp.124-131
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    • 2002
  • In this paper, an extended volumetric error model considering backlash in a three-axis machine tool was proposed and utilized for calculating the volumetric error of the machine tool at any position in three-dimensional workspace. Backlashes are interrelated; i.e. the angular backlash affects the straightness errors which then affect talc calculated squareness errors. Therefore, a new concept was introduced to define the backlash of squareness errors to incorporate the backlash of squareness error into the volumetric error, and the characteristics of the backlash of squareness error were investigated. The effects of backlash errors were assessed, by experiments. for 21 geometric errors of a machine tool. The backlash error was shown to be one of the systematic errors of a machine tool. And a generalized volumetric error model formulator for three-axis machine tools was developed, which allowed us to formulate machine tool synthesis error models far all possible machine tool configurations only with machine tool topology information. Based on these volumetric error model and model formulator, a computer-aided volumetric error analysis system was developed for a three-axis machine tool in this paper. Then the volumetric error at an arbitrary position can be obtained, and displayed in a three-dimensional graphic form.

일본 매엽 오프셋 인쇄기계의 동향에 관한 연구 (A Study on Trend of Sheet Fed Offset Printing Machine for Japan)

  • ;남수용
    • 한국인쇄학회지
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    • 제19권2호
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    • pp.1-11
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    • 2001
  • As for the sheet fed offset printing machine, the research and development of the speedup and multi-color for little rod are done. A charge per one offset printing machine became high year, and all kinds of control device became attach. Under this situation to need, many studies of printability of paper and ink are done. In particular improvement of surface strength of printing paper with speedup is needed. The use of non-wood paper and soybean printing paper with speedup is needed. The use of non-wood paper and soybean printing ink had been increased, study of those printability are important for printing development. From the viewpoint of quality and print important for printing development. From the viewpoint of quality and print productivity, the digital printing machine became lo on the introduction in Japan for the present.

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인간 - 기계시스템의 평가모델 (II) (A Model for Man-Machine System Evaluation (II))

  • 이상도;하정진;정중희;이동춘
    • 산업경영시스템학회지
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    • 제9권13호
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    • pp.17-22
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    • 1986
  • Man-machine system is an integrated total system which is linked by functions of man and machine, and the value of the system is determined by its compatability. And it is able to evaluate the system value on the aspects of utility, availability, and cost benefit. The authors previously represented the methodology of system utility using transfer functions, and this paper successively discusses the reliability of man-machine system. The reliability estimation and evaluation methodologies are briefly mentioned, and some examples are shown in this paper.

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중복설계와 하청을 고려한 셀 및 부품군 형성 절차 (A Machine Cell and Part Family Formation Procedure in Considering the Duplication and Subcontracting)

  • 문치웅;김효남;이상용
    • 품질경영학회지
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    • 제21권2호
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    • pp.224-231
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    • 1993
  • This paper propose a procedure to form the cell and part family using both of similarity coefficient method and mathematical programming in order to slove the exceptional part and bottleneck machine problems. In the procedure proposed by this paper, the machine duplication and subcontracting are considered to slove the bottleneck machine and intercellular moving part problems An example is given to show how this procedure works.

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A New Breed of Electric Machines - Basic Analysis and Applications of Dual Mechanical Port Electric Machines

  • Xu Longya
    • Journal of Electrical Engineering and Technology
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    • 제1권1호
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    • pp.73-79
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    • 2006
  • Conceptually, mechanical port of an electric machine can be doubled and the concept of dual-mechanical-port (DMP) will then give birth to a new breed of electric machines. In this paper, the various possible structures of DMP electric machine are discussed. Basic modeling and analysis issues related to the DMP electric machine are presented. An exemplary design of DMP machine is given and verified by FEM results. Potential applications and future research work are given to conclude the paper.

Analysis on Trends of Machine Learning-as-a-Service

  • Lee, Yo-Seob
    • International Journal of Advanced Culture Technology
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    • 제6권4호
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    • pp.303-308
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    • 2018
  • Demand is increasing rapidly in recent years than supply to machine learning professionals. To alleviate this gap, user-friendly machine learning software that can be used by non-specialists has emerged, which is Machine Learning-as-a-Service(MLaaS). MLaaS provides services that enable businesses to easily leverage ML capabilities without expertise. In this paper, we will compare and analyze features, interfaces, supporting programming language, ML framework, and Machine Learning services of MLaaS, to help companies easily use ML service.

Analysis of Machine Learning Education Tool for Kids

  • Lee, Yo-Seob;Moon, Phil-Joo
    • International Journal of Advanced Culture Technology
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    • 제8권4호
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    • pp.235-241
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    • 2020
  • Artificial intelligence and machine learning are used in many parts of our daily lives, but the basic processes and concepts are barely exposed to most people. Understanding these basic concepts is becoming increasingly important as kids don't have the opportunity to explore AI processes and improve their understanding of basic machine learning concepts and their essential components. Machine learning educational tools can help children easily understand artificial intelligence and machine learning. In this paper, we examine machine learning education tools and compare their features.

Comparison of Machine Learning Tools for Mobile Application

  • Lee, Yo-Seob
    • International Journal of Advanced Culture Technology
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    • 제10권3호
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    • pp.360-370
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    • 2022
  • Demand for machine learning systems continues to grow, and cloud machine learning platforms are widely used to meet this demand. Recently, the performance improvement of the application processor of smartphones has become an opportunity for the machine learning platform to move from the cloud to On-Device AI, and mobile applications equipped with machine learning functions are required. In this paper, machine learning tools for mobile applications are investigated and compared the characteristics of these tools.

Relationship Between Farm Land Structure and Machine Efficiency

  • Singh, Gajendra;Ahn, Duck-Hyun
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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    • pp.119-128
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    • 1993
  • Effective machine capacity is affected by the physical and geometrical conditions of the fields. In the small and scattered farmland structure field efficiency is greatly influenced by plot geometry. In this paper, a method for estimating field efficiency and effective machine capacity was developed . The developed method was applied to Korean paddy cultivation. Various time elements related to farm operations for small and scattered plots are discussed in this paper . Available working time is divided into two parts, viz. the preparation time for machine operation and actual working time. Two kinds of machine efficiencies, namely , Machine Efficiency 1, applicable on a single large plot or set of well consolidated plots ; and Machine Efficiency 2, applicable on small and scattered multiple plots, are considered. Based assumptions made and steps followed to construct the model are discussed. Effective capacity of each machine based on different plot geometries are calculated y the model. Machine efficiency on a single plot increases with increase in the dimension of longer side of the plot . Low speed, low theoretical capacity machines have higher machine efficiency which is only slightly influenced by plot geometry. As plot geometry is improved , the machine efficiency of high speed, high capacity machines increases rapidly. The effects of short side length and plot size on machine efficiency on a single plot depend on the type of farm operation. For a particular plot shape, as plot size increases, machine efficiency on multiple plots increases rapidly. The effects of consolidation on machine efficiency is highly significant if the plot size is small and/or machine size is large.

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