• Proceedings of the Korean Society of Precision Engineering Conference
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• 한국정밀공학회 2009년도 추계학술대회 논문집
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• pp.411-412
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• 2009

• Journal of the Korean Society for Railway
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• 제10권4호
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• pp.438-443
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• 2007

This paper proposes an integrated SE process for the development of railway systems with safety assessment included. Although the safety assessment process must be performed with SE process properly with good coordination, the interfaces between the two processes have not been clear. Thus, in many of safety critical system developments in Korea, it is difficult to assess safety in proper development phase. The process model proposed in this paper is based on both the concept of system life cycle and the repetitive use of SE process. In each of development phases, appropriate safety assessment methods are described. Also the evaluation of the integrated system incorporating safety factors is described. The resultant process model is expressed by the Enhanced Functional Flow Block Diagram (EFFBD) using a CASE tool. The model also allows timeline analysis for identifying activity flow and data flow, resulting in the effective management of process. In conclusion, the integrated process enable both the SE process and safety assessment process to cooperate with each other from early development phase throughout the whole system life cycle.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• 제35권5호
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• pp.53-61
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• 2003

In this study a model for the drying process in paper production plants was developed based on the mass and heat balances around drying cycles. Relationships for the heat transfer coefficients between the web and the air as well as between the drying cylinder and the web were extracted from the closed-loop plant operation data. It was found that the heat transfer coefficients could be represented effectively in terms of moisture content, basis weight and reel velocity. The effectiveness of the proposed model was illustrated through numerical simulations. From the comparison with the operation data, the proposed model represents the paper plant being considered with sufficient accuracy.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1988년도 한국자동제어학술회의논문집(국제학술편); 한국전력공사연수원, 서울; 21-22 Oct. 1988
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• pp.864-868
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• 1988

During the 1980s, the use of high-speed printing and copying machines which will not tolerate much variation in paper weight has increased. As a result, there is a growing demand for improved basis weight control systems for paper machines. Basis weight, the weight of a square meter sheet of paper, is the most important measure of paper consistency. Until quite recently, basis weight could only be controlled manually; this required experienced operators. The reasons for the difficulty in automating control of basis weight is due to the complexity and variability of process characteristics, the "noisiness" of the process (process disturbances), and actuator inadequacies. This paper describes a method of automatic control that we have developed; it incorporates the experience of expert operators, and the results of simulation, in confidence factors.e factors.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 한국펄프종이공학회 2004년도 추계학술발표집
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• pp.221-232
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• 2004

Paper process is complex and multivariable system. Identification of a paper process model is imperative for the development of predictive control method. 13-level Pseudo-Random Sequence Signals were used to identify the plant model in which the neural network model was considered model as a real paper process. Results of simulations for identification using 13-level PRS signals and Prediction Error Method are compared with plant operation data. From the comparison, we can see that the dynamics of the model show good agreement with those of real plant.

• Communications of the Korean Mathematical Society
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• 제12권3호
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• pp.725-741
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• 1997

This paper considers the problem of deriving exponential probability inequalities for product symmetric Poisson processes. As an application they are used to show the existence of regular version of some product process derived from L$\acute{e}$vy process.

• Journal of Korean Institute of Industrial Engineers
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• 제33권1호
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• pp.11-25
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• 2007

Despite surging interests in analyzing business processes, there are few scientific approaches to analysis and redesign of organizational structures which can greatly affect the performance of business processes. This paper presents a method for deriving and analyzing organizational relations from process models using social network analysis techniques. Process models contain information on who performs which processes and activities, along with the assignment of organizational units such as departments and roles to related activities. To derive social relations between organizational units from process models, three types of metrics are formally defined: transfer of work metrics, subcontracting metrics, and cooperation metrics. By applying these metrics, various relations among organizational units can be derived and analyzed. To verify the proposed method and metrics, they are applied to standard process models of the semiconductor and electronic, and automotive industry in Korea. This paper presents a taxonomy for diagnosing organization structure based on the presented approach. The paper also discusses how to combine analyses in the taxonomy for redesign of organizational structures.

• International conference on construction engineering and project management
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.1262-1267
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• 2005

It is still difficult to share and utilize the information generated at each phase of a steel box girder production process due to the spatial gap and different level of management information. The physical distance results in the inefficiency of the information transmission, the accidental omission and typos of the relative information, and so on. Various levels of management information make it difficult to embody a new management system. Eventually, these factors incur the loss of cost and schedule and interrupt development of a new management system. This paper analyzes a current process and presents graphical process flow by using IDEF0. Based this analysis, the research for new production process and work breakdown structure (WBS) is conducted. At the end of this paper, the conceptual design of this system is suggested. Through new management system, it is expected that the model proposed in this study will improve the management process in the steel box production, and the improved process will reduce the redundant cost and schedule information, transmission and deposit generated by manual paper.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• 제45권1호
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• pp.6-12
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• 2013

TFormic acid-hydrogen peroxide (or performic acid) pulping process needs milder reaction condition than other chemical pulping process. Two-step formic acid-hydrogen peroxide pulping process can produce the chemical pulp with similar pulp yield and lignin content compared with soda-anthraquinone process. Formic acid-hydrogen peroxide pulp can be produced less xylan content than other alkaline pulps, which favor for dissolving pulp production. Formic acid-hydrogen peroxide pulp showed better response beating than soda-anthraquinone(AQ) pulps with reaching target freeness with less beating. Also, formic acid-hydrogen peroxide pulp had better tensile index at similar freeness level compared with soda-AQ pulps.

• Journal of the Korean Graphic Arts Communication Society
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• 제30권1호
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• pp.59-69
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• 2012

This study is Long term preservation measures which is closely related to preserving paper records, record condition evaluation, preservation measure and is conducted as follows. As for Means to Evaluate the Deterioration and Damaged Conditions of Records, research and analysis has been made on the contamination and deterioration examples such as damage, dry, stapler, metal, contamination, acidification which are the characteristics of paper record damage types. The of Paper record is one of the key procedures to evaluate the record material and its physi-chemical status in many criteria and to suggest the best preservation method. Between 1970 and 2000, the main record materials was fine paper and OMR paper along with partly newspaper and coarse paper, whereas the main recording material was ball point pen. Overall damage and deterioration status is, for record materials between 1940 and 1960, high deterioration was found and in urgent need for preservation measure and more damages are caused by tapes, staplers and metals. As for records after 1970, there is light deterioration but needs preservation process. There are approximately 3 million records produces before 2000, and assuming that there are 30 pages per record and that 30% has been damaged or deteriorated, 27 million pages are subject to preservation process. Among damaged or deteriorated records, there are large number of records impossible to go through deacidification process so manual preservation and restoration process is necessary as well. Securing manpower having preservation and restoration skills as well as preservation equipment(deacidification process, preservation and restoration) is in urgent need.