• Journal of Satellite, Information and Communications
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• v.2 no.1
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• pp.7-13
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• 2007

A new and effective Doppler effects compensation method based on constellation estimation as well as an average power saving strategy by modified modulation scheme utilizing zero point constellation are presented with theoretical analysis and relevant simulations. The suggested schemes are proved to be very effective for satellite OFDM signals relayed by power limiting transponder for the mobile terminal on high speed vehicles.

• Journal of the Korea Safety Management & Science
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• v.11 no.1
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• pp.93-101
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• 2009

The use of the gas turbine for power supply is increasing recently. Accordingly, the operation and maintenance cost of the gas turbine is gradually increasing and the various efforts to cut the cost are needed. For an operation and maintenance cost saving of the gas turbine, reductions of the new purchasing charge and the reproduction repair cost of the hot gas parts are required through more effective operation and life management methods for the hot gas parts. The hot gas parts are the main parts of the gas turbine and they are replaced with the periodic. In this research, efficient operation and life management methods for the hot gas parts were presented with the cases. The methods were analyzed and verified based on real data and the cases for improving a lifetime were utilized in the field.

• Journal of Ocean Engineering and Technology
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• v.14 no.4
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• pp.62-97
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• 2000

Recently the research for utilization of waste heat produced from electric power plants, casting factories, heat treating factories or commercial are being afforded by the need for energy saving. The objective of this study is to develop a thermoelectric generation system which unused energy from close-at-hand sources such as garbage incineration heat and industrial exhaust etc. into electricity. This paper a thermoelectric technology on a optimum system design method and efficiency and cost effective thermoelectric element on order to extract the maximum power output from energy conversion of waste energy. It is shown that the longitudinal stresses of module contacted with two point constrained Al tubes could be released more than those with a one-point constrained.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.2
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• pp.239-241
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• 2009

In this paper, an estimation methodology for stand-by energy savings of electric appliances is proposed and some case studies are carried out for televisions. The methodology is based on learning curves and diffusion models, which are able to explain the market characteristics such as market prices and the diffusion speed. Some models were developed to estimate power and energy savings for high-efficient appliances and these model have been used broadly. These models are also applied to this study and modified to estimate stand-by energy savings.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.56 no.4
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• pp.179-185
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• 2007

In this paper, the method of computing demand rate with respect to a transformer capacity is proposed and addressed to predict a future demand rate. The simulation data are taken from switchgears of a real medium voltage transformer. Data taken from the electrical instrument at 22.9 kVY power receiving panels are employed to evaluate the correlation between demand rate and power usage of transformer. It is verified a usefulness with respect to an proposed index of demand rate for transformer by using a least square error of regressive modeling, As a result of investigation and simulation on the spot to a few buildings, it is considered that there is necessity to make a partial amendment of demand rate being applicable currently for electrical energy saving in domestic.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.466-468
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• 2005

Recently, the demand for the development of high quality and high speed laser printer and efficient power utilizations are required. Among complicate electro-mechanic devices in laser printer, the toner fusing unit consumes above 90[%] of all electrical energy needed for printing devices. Therefore, the development of more effective energy-saving toner fusing process becomes a significant task of much great demand. Generally, there are several way to implement fusing unit, among them this paper present a new hybrid induction heating method. The proposed induction heating method enables to increase coupling coefficient between heating coil and heat roller also to Increase total energy transfer efficiency. Therefore the proposed IH inverter system provide very fast W.U.T.(Warm UP Time), also high efficiency. Through experimental result, the proposed control system is verified.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.52 no.4
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• pp.154-160
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• 2003

The switched reluctance motor(SRM) has a considerable potential for industrial applications because of its high reliability as a result of the absence of rotor windings. In some applications with SRM, a parallel switching strategy is often used for cost saving, increasing of current capacity and system reliability. This paper proposes a new parallel switching strategy of SRM using parallel winding. While conventional parallel switching devices are connected in a phase winding, power devices are connected in the parallel windings wound in each pole of stator in the proposed method. Paralleling strategy for current sharing in the proposed method can be easily determined without considerations of any nonlinear characteristics of power devices such as conduction resistance, threshold voltage and gain factor. The proposed paralleling strategy is verified by the mathematical analysis and experimental results.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.34S no.3
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• pp.1-11
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• 1997

Since the radio spectrum is limited, future wireless system will have micro cellular architecture in order to provide multimedia traffic services on personal communicatons network. The small coverage area of micro cellular systems results in frequent hadnoffs and location updates. We focuse on network load and terminal power due to frequent location updates and propose a location tracking scheme using embedded-pager PCS terminals. The proposed scheme is expected to minimize theconsumption of PCS terminal powr and improve the receiving rate of callee because of the power saving mechanism and the embedded-pager PCS terminal. This paper proposes signaling flows among the network elements for the proposed location tracking scheme. The signaling flows are accomodated to not only the existed network architectures but alsothe ATM backbone network arcitecture. To verify the signaling flows, we used petri-Net model. The resutls show that the signaling flows are suitable to our proposed location tracking scheme.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.3
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• pp.517-523
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• 2011

A lot of DSM (Demand Side Management) programs have been implemented to promote the effective utilization of resources and the rational development of power industry, and various economic analyses and policy-based studies on DSM have been executed to determine effective subsidy budget. In this paper, a new objective function for deciding an optimal incentive allocation among various programs is presented by introducing the maximization of the total saving power of the programs. For simplicity, the objective function and the constraints is linearized to apply LP(Linear Programming) method. LP program based on Simplex Method was developed by MATLAB. An optimal incentive allocation of 4 DSM programs is presented by the use of the developed MATLAB program.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.1
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• pp.12-18
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• 2003

Recently the research for utilization of waste heat produced from electric power plants, casting factories, heat treating factories or commercial building are being afforded by the need for energy saving. The objective of this study is to develop a thermoelectric generation system which converts unused energy from close-at-hand sources such as garbage incineration heat and industrial exhaust etc. into electricity. This paper presents a thermoelectric technology on a optimum system design method and efficiency and cost effective thermoelectric element on order to extract the maximum power output from energy conversion of waste energy. It is shown that the longitudinal stresses of module contacted with two point constrained AI tubes could be released more than those with a one-point constrained.