• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.541-542
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• 2006

The dispersed generation is recently increased introduction for the energy supply rationalization and effective management of power system. But the dispersed generation causes to the various trouble that isn't occurred in the past, for example, the two way systems have an effect on the mistake action of protection equipment and the power quality. In this paper, we research the influence on the harmonic when the dispersed generation is interconnected with distribution system. To achievement, we construct the interconnecting dispersed generation and distribution system which is applied to the permission of harmonic emission. After that, we simulate about the harmonic of distribution system interconnection dispersed generation by the PSCAD/EMTDC analyzing transient state of the power system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.149-151
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• 2005

A new approach considering CO2 air pollution constraints in the long-term generation mix is proposed under uncertain circumstances. A characteristic feature of the presented approach in this paper is what effects give the air pollution constraints in long term best generation mix. Best generation mix problem is formulated by linear programming with fuel and construction cost minimization with load growth, reliability (reserve margin rate) and air pollutionconstraints. The proposed method accommodates the operation of pumped-storage generator. It was assumed in this study that the construction planning of the hydro power plants is given separately from the other generation plans. The effectiveness of the proposed approach is demonstrated by applying to the best generation mix problem of KEPCO-system, which contains nuclear, coal, LNG, oil and pumped-storage hydro plant multi-years.

• 약학회지
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• 제41권3호
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• pp.365-369
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• 1997

Human chorionic gonadotropin (hCG) is a placental hormone and is involved in maintenance of the corpus luteum during pregnancy. In the present study, effect of hCG on nitiric ox ide (NO) generation from peritoneal macrophage was examined. hCG ahd no effect on NO generation by itself, whereas recombinant interferon- ${\gamma}$ (rIFN-${\gamma}$) alone had modest activity. When hCG was used in combination with rIFN-${\gamma}$, there was a marked cooperative induction of NO generation in a dose-dependent manner. The optimal effect of hCG on NO generation was shown at 6 hr after treatment with rIFN-${\gamma}$. Furthermore, northern blot analysis of showed that hCG increased the expression of inducible NO synthase(iNOS) gene. These results suggest that hCG induces NO generation from macrophages by increasing the expression of iNOS gene.

• Journal of Welding and Joining
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• 제15권2호
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• pp.72-80
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• 1997

The spatter generation rate of GMA welding with $CO_2$ gas shielding was measured with the change of welding conditions such as wire feeding rate and welding voltage and then the results were analized with the accompanying changes in metal transfer mode and in bead geometry. The spatter generation rate (SGR) was relatively low not only wit the short circuit transfer but with the truely globular transfer mode. However, the SGR resulted with the mixed mode were consistantly high. The resultant wave pattern of mixed mode was due to the coexistance of short-circuit and globular transfer and characterized by the frequent appearance of instantaneous short circuit. Considering the result of SGR and that of bead geometry, it could be concluded that when the wire feeding rate (or welding current) was either low or high, the optimum bead shape could be obtained along with the low spatter generation. However, in the middle range of wire feeding rate, the optimum bead shape was only obtained in the mixed mode condition resulting in the high spatter generation.

• 상하수도학회지
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• 제23권3호
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• pp.331-337
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• 2009

Electrolysis produces hypochlorous acid by using a small quantity of NaCl as electrolyte. This process maximizes the stabilization of drinking water through the control of chlorine residual concentration. This study investigated free chlorine generation by an electrolytic method using $Ti/IrO_2$ and stainless steel. The generation of free chlorine was increased with increasing hydraulic retention time, voltage, chlorine ion concentration and the number of electrodes. However, the change of pH did not affect the generation of free chlorine. There was no significant difference on the behavior of chlorine concentration between electrolytic method and NaOCl injection. In this study, the concentration of free chlorine predicted model based on power functional model was developed various under conditions. Electrolysis free chlorine generation model can be effective tool in the estimation of free chlorine generation.

• Journal of Communications and Networks
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• 제14권4호
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• pp.385-395
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• 2012

This paper tackles the problem of generating shared secret keys based on the physical characteristics of the wireless channel. We propose intelligent quantization mechanisms for key generation, achieving high secret bits generation rate. Moreover, some practical issues affecting the performance of the key generation mechanism are deeply investigated. Mainly, we investigate the effects of delay and mobility on the performance and we enhance the key generation mechanism accordingly. As a result, this paper presents a framework towards robust key generation from multipath wireless channels.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 추계학술대회 논문집 학회본부 A
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• pp.113-115
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• 2000

So far, it was very difficult to simulate the dispersed generation system including PV generation system using EMTP or EMTDC because the source of the dispersed generation system has a particular VI characteristic equation. In this paper, a novel simulation method of PV generation system has proposed and a new solar cell component for EMTDC is also developed. The VI characteristic equation of solar cell is used in order to realize the solar generation system in EMTDC simulation. Consequently the simulation of PV power generation system using field data is realized and acceptable results, which show close match between the real data of PV panel and the simulated data, were obtained.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 A
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• pp.106-109
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• 1992

This paper Introduces the concept of the generation cost of generating utilities and its calculation methods. Also, the economic evaluation method using generation cost which is called as a screening curve method will be presented along with the benefits and disadvantages of this concept. Next, the least-cost electric utility planning techniques which is used very widely in many countries will be Introduced In comparison with screening curve method. In this aspects, the optimal dynamic mix can be determined as a result. By comparing these two concepts, we will get the concrete concept why the economic evaluation method using generation cost can not be used for the future generation expansion planning.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2006년도 추계 학술대회논문집
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• pp.70-73
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• 2006

Mesh generation for the region of interest is prerequisite for numerical analysis of governing partial differential equations describing phenomena with proper physic. Mesh generation is, however, usually considered as a major obstacle for a routine application of numerical approaches in Engineering applications. Therefore automatic mesh generation is highly pursued. In this paper automated quadrilateral surface mesh generation is proposed. According to the present method, Cartesian cells of proper resolution for a region bounding the whole region of interest are first generated and the interior cells are identified. Then projecting their surface meshes onto the boundary surfaces gives surface mesh consisting of quadrilateral cells. This method has been implemented as an application program, and example cases are given.

• 전기학회논문지
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• 제61권11호
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• pp.1571-1577
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• 2012

This paper presents a method for assessing the voltage sag performance of power system involving wind power generation. Wind power generation is considered as one of the most desirable renewable energy sources. However, wind power generation have uncertain energy output and it is difficult to control the output. The existing methods of voltage sag assessment are not reflected the characteristics of wind power generation. Therefore, in order to more accurately assess the voltage sag performance, the probability of wind power operation is evaluated. In this paper, the probability is determined by combining the wind speed model with the output curve of wind turbine. The probability of wind power operation is reflected as a parameter in voltage sag assessment. The proposed method can provide more accurate results of voltage sag assessment for the case involving the wind power generation.