• Proceedings of the KIPE Conference
• /
• 2008.06a
• /
• pp.40-42
• /
• 2008

This integrated magnetic (IM) transformer is proposed for a phase shifted full bridge (PSFB) converter with zero voltage switching (ZVS). In a new IM transformer, the transformer is located on the center leg of E-core and the output inductor is wound on two outer legs. The proposed circuit is analyzed electrically and magnetically. An E-core is redesigned and implemented. The proposed IM transformer is experimentally compared with the conventional one through a 1.2kW prototype converter.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.5A
• /
• pp.426-432
• /
• 2007

The MAP algorithm is designed and implemented through the sliding window method for turbo decoding. First, the implementation issues, which are the length of the sliding window and the normalization method of state metrics are reviewed, and their optimal values are obtained by the simulation. All component schemes of the decoder including the branch metric evaluator are also presented. The proposed MAP architecture can be easily redesigned according to the size of sliding window, that is, sub-frame length because of its simplicity on buffer control.

• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.50 no.6
• /
• pp.263-272
• /
• 2001

The paper presents the design of a segmented type synchronous reluctance motor(SynRM) to increase its torque and power factor. The main feature of a segmented type synchronous reluctance motor is the flux barrier. Thus, the design process to find optimum value of various geometric parameters including flux barrier will be explained. Optimum value of each parameter is found where the d, q inductance difference and saliency ratio are maximized because these inductance characteristics are related to torque and power factor. Finite Element Analysis will be used to simulate motor characteristics. Analysis results of redesigned SynRM show higher saliency ratio over 10 and improved value of maximum power factor.

• International Journal of Air-Conditioning and Refrigeration
• /
• v.12 no.4
• /
• pp.192-197
• /
• 2004

A capillary tube, which is a common expansion device in small sized refrig-eration and air-conditioning systems, should be redesigned properly to establish an optimum operation cycle of a refrigerating system with alternative refrigerants. Based on experimental data for R-22, R-290, and R-407C, an empirical correlation is developed to predict mass flow rate through capillary tubes. Dimensionless parameters are derived from the Buckingham Pi theorem, considering the effects of operating conditions and capillary tube geometry on mass flow rate. Approximately $97\%$ of the present data are correlated within a relative deviation of $\pm\;10\%.$ The present correlation also predicts the data obtained from open literature within $\pm\;15\%.$ In addition, rating charts of refrigerant flow rate for R-12, R-22, R-134a, R-152a, R-407C, R-410A, R-290, and R-600a are developed.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2003.10b
• /
• pp.143-146
• /
• 2003

In this paper, a new preform design method is proposed to eliminate the excessive flash in metal forging process. After carrying out finite element simulation of the process with an initial billet, backward particle tracing is performed from the outlet of the flash. Then, the region which belongs to the flash is easily found .. The process is analyzed again with the redesigned billet which is removed that region the above mentioned region. The optimal preform shape which minimizes the amount of flash without changing the forgibility can be obtained in several iterations.

• 제어로봇시스템학회:학술대회논문집
• /
• 2005.06a
• /
• pp.675-679
• /
• 2005

This paper deals with the problem of gust load alleviation in active control for the case that aeroelasticity takes place due to interaction between wing structure and aerodynamics on wing when aircraft meets gust during flight. Aeroservoelasticity model includes wing structure modeled in FEM, unsteady aerodynamics in minimum state approximate method, and models of actuator and sensors in state space. Based on this augmented model, digitally redesigned gust load alleviation system is designed in sampled-data control technique. From numerical simulation, this digital control system is effective to gust load on aircraft wing, which is shown in transient responses and PSD analysis to random gust inputs.

• Journal of Industrial Technology
• /
• v.28 no.B
• /
• pp.149-156
• /
• 2008

A reliability model of Level II AFDA is developed to analyze the stability of armor units on the sloped coastal structures. Additionally, the partial safety factors of random variables related to armor units can be straightforwardly evaluated by applying the inverse-reliability method in which influence coefficients and uncertainties of random variables, and target probability of failure are combined directly. In particular, a design equation for armor units is derived in terms of the same criteria as deterministic design method in order to apply the reliability-based design method of Level I without some understanding to the reliability analysis. Finally, it is confirmed that several results redesigned by the reliability-based design method of Level I have satisfactorily agreement with results of CEM as well as those of Level II AFDA.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2000.11a
• /
• pp.344-347
• /
• 2000

In this paper, a redesign of computer case is proposed by applying some guide lines of assembly and disassembly to an existing computer case. Some problems such as increase of number of disassembly and vibration, difficult assembly and disassembly from unfittable covers are recognized through analysis of geometrical structure and practical assembly and disassembly. A solution of these problems is proposed through ideas of ease of assembly and disassembly. Design for Environment Software is used to evaluate both redesigned and existing products. Time of assembly and disassembly and MET-point are especially calculated by the software, and these data give us a good guide for analysis of ease of assembly, ease of disassembly and environmental influence in both products.

• Journal of Korean Society for Quality Management
• /
• v.36 no.4
• /
• pp.65-76
• /
• 2008

The purpose of this study is to contribute to escalation of a management quality of local public enterprise through integrating local public enterprise evaluation(LPEE) and Malcolm Baldrige Model(MBM). In order to achieve the purpose, I suggested that develop an integration model of LPEE and MBM criteria and use AHP(Analytic Hierarchy Process) as a technique posting weight value to criteria. Of two suggests, it is the former to date or discuss seriously. Therefore the integration model is redesigned for leadership/strategy category(leadership, strategy), management system category(customer management system, business management system, measurement/knowledge management system), and management result category(business result, customer satisfaction result, human resource management result, financial management result).

• 한국정보디스플레이학회:학술대회논문집
• /
• 2008.10a
• /
• pp.1305-1308
• /
• 2008

In this study, we redesigned the reliable integrated on-panel display gate driver that was equipped with dual pull-down as well as controlled discharge-path structure to reduce the high voltage stress effect and realized with TSMC 0.35 um CMOS-based technology before. An improved discharge path and a low noise design are proposed for our new a-Si TFT process implementation. Our novel reliable gate driver design can make each cell of shift register to be insensitive to the coupling noise of that stage.