• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.17 no.3
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• pp.1-12
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• 2021

In this study, the effects of various operational conditions for floor radiant heating system were researched by experiments. Hot water supply set temperature, indoor air set temperature and supply water flowrate were considered as operational conditions. The control method for this system is On-Off control of automatic thermostatic valve. The purpose of this study is to evaluate indoor thermal control characteristics and energy performance, respectively. As a result, if lower supply water temperature is applied, the supply and return temperature difference is reduced and energy consumption of heat supply is also reduced.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.33 no.4
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• pp.311-320
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• 1997

We selected horse mackerel Trachurus japonicus, mackerel Scomber japonicus and arrow squid Todarodes pacificus, to be used in the experiment. These fishes migrate to the Cheju coast and were caught by set-net. We studied on the attracting effect and the leading effect on the fish school using incandescent lights in an outdoor water tank at the Marine Research Institute Cheju National University. The results obtained are summarized as follows; 1. The horse mackerels, mackerels and arrow squids were actively attracted to the incandescent light. The optimum illumination and the reactions of each fish school were different though. 2. We turned the first attracting lamp on and turned it off after ten minutes. Then we turned the second attracting lamp on and turned it off after another ten minutes. The reaction of each fish school was a little bit different, but it worked to lead them to their destination. 3. We turned the three attracting lamps on at the same tune. After ten minutes, We turned the first attracting lamp off. After another ten minutes we turned the second attracting lamp off. The reaction of each fish school was a bit different, but it worked to lead them to their destination. 4. One incandescent light was moving. The reaction of each fish school was a little bit different, but it worked to lead them to their destination.

• Journal of Korea Technology Innovation Society
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• v.6 no.1
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• pp.60-73
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• 2003

There are many studies on spin-offs from college, but there is little concern on start-ups, which are set up by college and operated by professors. We call this type of start-up as college start-up. We check the problems and solutions of this type of start-ups. We propose three factors for success; prior checking of profitability of the business, preparation of relevant school policies and profit sharing with school and professors participated.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.760-763
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• 2004

This work presents OLP system made independently in HSD for sub-assembly welding robot system set already and assembly welding robot system developed lately on the low speed diesel engines. This paper focuses on the DB module and the job creation based upon it. Also, It contains the welding history DB that saves the information of jobs executed after welding.

• Journal of the Korean Graphic Arts Communication Society
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• v.15 no.1
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• pp.41-55
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• 1997

We examine various digital halftoning technique and their application to printings. Three such technique are the error diffusion, cluster dither and disperse dither method. This paper describes a new tone correction halftone method to compensate dot gain. Input digital level are transformed by tone correction characteristics. The function of tone correction are solved from the printer response characteristic. The experimental results show that the proposed method is useful and valid.

• Journal of the Korean Graphic Arts Communication Society
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• v.15 no.2
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• pp.131-143
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• 1997

Surface sizing is one of the important process to the paper making. Surface sizing had an effect on penetration of oils, physical propertiesm water resistance for the paper. This study was carried out for the purpose of improving printability with surface sizing of domestic newspaper. The samples were prepared by means of TAPPI method(TAPPI 205 om~88), and were wested by IGT printability tester. The results of this study showed that the set-off was reduced on the surface sized with oxidized starch.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.943-946
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• 1999

In this paper, we present a new clock routing algorithm which minimizes total wirelength under any given path-length skew bound. The algorithm onstructs a bounded-skew tree(BST) in two steps:(ⅰ) a bottom-up phase to construct a binary tree of shortest-distance feasible regions which represent the loci of possible placements of clock entry points, and (ⅱ) a top-down phase to determine the exact locations of clock entry points. Experimental results show that our clock routing algorithm, named BST/DME, can produce a set of solutions with skew and wirelength trade-off.

• Journal of Advanced Marine Engineering and Technology
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• v.16 no.1
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• pp.27-34
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• 1992

In eliminating the nonlinear characteristics such as piston displacement dift and difference in speeds of the reciprocating motion due to their nonsymetrical structure of single rod cylinder, the linear model can be given by equivalent outside disturbance, etc. The position control method of single rod cylinder servosystem using the sliding mode control of VSS was suggested and the good results without off-set are compared with PD control of fixed structure system.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.37 no.12
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• pp.879-883
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• 1988

In this paper, self tuning control of interconnected systems are dealt in view point of large scale system control. The plant model is given in MIMO ARMA procss. This process is simlified as independent SISO ARMA processes having offset terma, which are considered as effects of interconnections. In each decentralized system, self tuning controller with instrumental variable method is adopted. As a result, this algorithm enables the paramter estimation to be unbiased and non-drift. This controller contains a new implicit offset rejection technique. Simulation results consider well with the analysis in case of linear interconnection.

• Proceedings of the KWS Conference
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• 2003.05a
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• pp.149-151
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• 2003

The development of lightweight car bodies is the most prominent issue in the automotive industry today, in preparation of environmental regulations such as reduction of CO$_2$ emissions. Also, with the recent implementation of mandatory off-set collision test, many studies have been carried out to enhance the safety of automobiles. Recently, TRIP(Transformation Induced Plasticity) steel has developed as a prominent alternative due to its high strength and superior elongation. In this study, TRIP steel weldability is evaluated with lobe curve, continuous spot welds, shunt effect, and weld of edge position.