• Journal of Institute of Control, Robotics and Systems
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• v.6 no.3
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• pp.329-337
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• 2000

This study describes a pressure tracking control of hydroforming process which is used for precision forming of sheet metals. The hydroforming operation is performed in the high-pressure chamber strictly controlled by pressure control valve and by the upward motion of a punch moving at a constant speed, The pressure tracking control is very difficult to design and often does not guarantee satisfactory performances be-cause of the punch motion and the nonlinearities and uncertainties of the hydraulic components. To account for these nonlinearities and uncertainties of the process and iterative learning controller is proposed using Cerebellar Model Arithmetic Computer (CMAC). The experimental results show that the proposed learning control is superior to any fixed gain controller in the sense that it enables the system to do the same work more effectively as the number of operation increases. In addition reardless of the uncertainties and nonlinearities of the form-ing process dynamics it can be effectively applied with little a priori knowledge abuot the process.

• Journal of Korea Spatial Information System Society
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• v.11 no.2
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• pp.34-38
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• 2009

Based on the design of the LIS of GuangZhou and BeiJing, this paper discusses the resolution of the LIS with the kernel of process management. It applies the idea of workflow in the management supporting stratum, applies the process-oriented mechanism in the definition, coordination, supervision and control of the management process. The scheme has the character of information-media-oriented, work process dynamic changing supported, application system extended and restructure supported and is independent of the running environment of specific work.. Due to the previous character, the LIS is flexible, useable, elastic and able to support the dynamic application.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.10 no.1
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• pp.1-6
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• 2014

PID(Proportional, Integral, Derivative) controller is one of the most used process controllers in nuclear power plants. The optimized parameter setting of process controller contributes to the stable operation and efficiency in the operating nuclear power plants. PID parameter setting is tuned when new process control system is established or process control system is changed. It is a burdensome work for I&C(Instrument and Control) engineers to tune the PID controller because it requires a lot of experience and knowledge. When the plant is in operation, inadequate PID parameter setting can be the cause of the unstable process of the plant. Therefore the results of PID parameter setting should be compared, simulated, verified and finally optimized. The practical PID tuning methods used in process controller are tuning operation calculation(Ziegler-Nicholes, Minimum TIAE, Lambda, IMC), exclusive tuning program based on computer and Matlab application. This paper introduces the various tuning methods and suggests an optimized PID tuning process in the operating nuclear power plants.

• Fashion & Textile Research Journal
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• v.14 no.4
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• pp.597-606
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• 2012

To increase the productivity and product quality of customized baseball jerseys, this study developed a multi-variable system for a production process that efficiently controls diverse production management factors. The working time was measured through the establishment of a standard process where skilled workers and Chinese factory workers manufactured 5 sets of the same basic design jerseys. Based on the measured working time (1,136 seconds/per unit), the multi-variable process control system was developed, where hourly production management is possible according to the involved workers and equipment types. Each process was assigned accoding to the production management factors for a total of 28 standard processes. The processes were developed based on consideration of work characteristics according to the order of needlework of open-type set baseball jerseys with sleeves(the basic design of baseball jerseys)to result in a customized production system structure that could be set up with multi-variables. As a result, a total 12 types of systems were developed in consideration of the personnel involved and the number of equipments. The optimal production management system (with the highest efficiency compared to the number of workers)was A-2, B-1, C-1. D-2, E-2, F-1, and G-1. This system had extremely high efficiency and showed 99% assignment efficiency for the 7-person team. Though not optimal, possible process assignment for each working personnel is proposed as a reserve process in case work modification is inevitable due to malfunctions and the absence of equipments.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.3
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• pp.10-17
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• 2016

Control Chart is a graph which dots the characteristic values of a process. It is the tool of statistical technique to keep a process in controlled condition. It is also used for investigating the state of a process. Therefore many companies have used Control Chart as the tool of statistical process control (SPC). Products from a production process represent accidental dispersion values around a certain reference value. Fluctuations cause of quality dispersion is classified as a chance cause and a assignable cause. Chance cause refers unmanageable practical cause such as operator proficiency differences, differences in work environment, etc. Assignable cause refers manageable cause which is possible to take actions to remove such as operator inattention, error of production equipment, etc. Traditionally ${\bar{x}}-R$ control chart or ${\bar{x}}-s$ control chart is used to find and remove the error cause. Traditional control chart is to determine whether the measured data are in control or not, and lets us to take action. On the other hand, RNELCC (Reflected Normal Expected Loss Control Chart) is a control chart which, even in controlled state, indicates the information of economic loss if a product is in inconsistent state with process target value. However, contaminated process can cause control line sensitive and cause problems with the detection capabilities of chart. Many studies on robust estimation using trimmed parameters have been conducted. We suggest robust RNELCC which used the idea of trimmed parameters with RNEL control chart. And we demonstrate effectiveness of new control chart by comparing with ARL value among traditional control chart, RNELCC and robust RNELCC.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.10a
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• pp.51-56
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• 2001

This work describes reduction of disturbance created by driving actuator in milling process. To the end, controller includes disturbance dynamics. Experimently it is shown that steady disturbance can be rejected to a certain degree.

• Korean Journal of Construction Engineering and Management
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• v.7 no.1 s.29
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• pp.128-137
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• 2006

Recently the role and the importance of design value engineering is expected to be high, so research is needed for its effective accomplishment. But in domestic arena, the introduction of the history of design value engineering is too short and insufficient in act of research. Therefore in this research we have suggest the standard for the effective accomplishment of design value engineering work. The way is the abstraction many causes. firstly, we analyzed the team project case of value engineering professional instruction. second, we analyzed the cause of problem produced in accomplishment process of design value engineering work through research for the professional field. So from the base of the analyzed content, we have suggest main control factor for the effectiveness of design value engineering work and the following scheme and process of work efficiency optimization.

• Journal of the Korea institute for structural maintenance and inspection
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• v.2 no.3
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• pp.176-187
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• 1998

The Dismantlement and Construction of the buildings have the characteristic of floating change with repetition within a Time Schedule which has fixed resources, that is, Manpower, Materials and Equipments, and involve many disaster factors in performing each processes. But as these factors are variable, a work supervisor should be able to understand data analysed distinctive factors of each activities systematically, organizationally, and scientifically, and diagrammatic information media so that he can control any complex and situation beyond forecast. Thus this study is intended to be a barometer of weighing if the existing process schedule has taken security into consideration by making the characteristics of organization and action of Work package per process in a building field with more factors like these into a network system and is intended to minimize construction disasters by systematizing this into a Transformational Network.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.05a
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• pp.92-100
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• 2006

In many common control charting situations, the statistic to be charted can be viewed as the output of a linear filter applied to the sequence of process measurement data. In recent work that has generalized this concept, the charted statistic is the output of a general linear filter in impulse response form, and the filter is designed by selecting its impulse response coefficients in order to optimize its average run length performance. In this work, we restrict attention to the class of all second-order linear filters applied to the residuals of a time series model of the process data. We present an algorithm for optimizing the design of the second-order filter that is more computationally efficient and robust than the algorithm for optimizing the general linear filter. We demonstrate that the optimal second-order filter performs almost as well as the optimal general linear filter in many situations. Both methods share a number of interesting characteristics and are tuned to detect any distinct features of the process mean shift, as it manifests itself in the residuals.

• Proceedings of the KIEE Conference
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• 2004.07d
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• pp.2386-2388
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• 2004

Recently, rapid process of network technology has an effect on the field of control engineering. And it gives effect to network control system(NCS) research that grafts existing control system and network has been studied. According to one-chip development of TCP/IP that is the most useful in LAN server for hardware, it can usefully and conveniently apply to network control system before. This paper construct network control system that can work close-loop control takes advantage of Ethernet that is the most for general data transmission network. Here, protocol uses for data transmission makes use for TCP/IP. This work the basic data transmitter-receive experiment to take advantage of network node was produced. And then, DC-motor can be control plant. Finally, I will prove to build speed control system of multiple DC-motor through Ethernet.