• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.380-381
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• 2006

정부는 제3차 전력수급기본계획 수립에 대비하고, 고가로 공급되는 LPG 수요를 대체하기 위한 제주도청의 LNG 공급요청과 제주지역에서 LNG사업을 희망하는 한국가스공사의 의향 그리고 한국전력공사의 전력연계선 추가건설 추진 등을 종합적으로 감안하여 이에 관한 세부 연구를 한국전기연구원에 위탁한 바 있다. 분석을 위한 전제 자료는 유관 사업자와 중립적 입장에 있는 한국전력거래소의 세밀한 검토와 합의를 거쳐 정해졌으며, 전력과 가스부문은 물론 이와 관련된 사회적 비용(Social Cost)이 모두 고려되었다. 아직까지 최종 결론은 확정되지 않았지만 연계선을 추가로 건설하는 방안이 가장 우세한 것으로 전해지고 있다. 따라서 본 논문은 추가 전력연계선 건설과 제3차 전력수급기본계획시 발전사업자가 제출한 제주지역에서의 발전소 건설 의향 등을 반영하여 2010년 이후 제주지역에서의 발전사업을 분석하고 전망하였으며, 예상되는 문제점을 중심으로 발전사업자 입장에서 개선방안을 제시하고자 하였다.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.418-419
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• 2006

After electricity power industry restructuring, "Long term power development plan", setting up by government, is replaced by "Basic plan of electricity supply and demand". In this basic plan, one of the most important factors is assessment of appropriate capacity margin. The benefit of GENCO is decided by the market price, and the price is largely affected by the level of reserve margin. As a consequence, appropriate reserve margin is determined by market power. However, Cost Based Pool(CBP) is a limited competitive market, and government policy for supply and demand is very important factor or reserve margin determination. This paper points out issues about existing reserve margin assessment method which is used in basic plan and suggests improved assessment method. In the case study, capacity margin is calculated by proposed assessment method and result shows the advantages of suggested method.

• Proceedings of the KIEE Conference
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• 2006.11a
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• pp.264-265
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• 2006

국내계통의 적정설비예비율은 현재까지 정부에서 제시하고 있는 일정 LOLP(Loss of Load Probability)기준 0.5(일/년)을 역으로 환산하여 결정되어진다. 그런데 현재의 LOLP의 산출은 시간별 부하변동특성을 반영하지 못하고 있다. 본 논문에서는 국내 장기전원계획시 사용하고 있는 최적전산모형(WASP)의 이러한 단점을 최대한 극복할 수 있도록 분기를 조절하고 기존의 방법과는 다른 O&M cost 분류를 적용하석 각각의 결과에 따른 분석과 이러한 특성을 반영했을 경우 년도 별로 환산된 일정 신뢰도 기준하의 필요 설비예비율의 사례를 분석하였다.

• 한국태양에너지학회:학술대회논문집
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• 2008.11a
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• pp.21-24
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• 2008

In this paper, we introduce the status of concentration photovoltaic system. Currently, crystalline silicon solar has 90% of total solar market. But in a few years, the concentration solar system is expected to be main one because cost increasement of silicon material is not stabilized unit now. At 2012, it will take 5% of the whole solar market. Less expensive, material requirement and high system efficiency give high driving force for intensive research on concentration system. It is time for us to initiate the basic study and evaluate the long term stability compared to crystalline silicon system. The detail discussion will be shown in the following paper.

• Korean Journal of Bronchoesophagology
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• v.17 no.2
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• pp.92-97
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• 2011

MMinimally invasive surgery (MIS) for early stage lung cancer has been an important treatment modality. However, the ergonomic discomfort and counterintuitive instruments hindered the application of video-assisted thoracic surgery (VATS) to more advanced procedures. To improve the compliance with MIS, robotic surgery was adopted. This advance aimed to alleviate the shortcomings of VATS by maximizing the comfort of the surgeon while providing instruments that enabled technically demanding operations and three-dimensional views with increased freedom for intrathoracic movement owing to EndoWrist$^{(R)}$. In this session, we introduced the clinical applications and its results of robot-assisted thoracic surgery in the field of lung cancer surgery. In conclusion, robot-assisted pulmonary resection with lymph node dissection for lung cancer is safe as well as feasible, and it results in a satisfying postoperative outcome. Robot-assisted surgery may provide a good alternative to conventional open or thoracoscopic surgery for lung cancer, provided that the cost effectiveness and long-term prognosis are confirmed.

• Proceedings of the Korean Geotechical Society Conference
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• 2007.09a
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• pp.39-52
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• 2007

A new type bridge combining an integral bridge and a pair of geosynthetic-reinforced soil (GRS) retaining walls having full-height rigid (FHR) facings, called the GRS integral bridge, is proposed. The geosynthetic reinforcement layers are connected to the FHR facings (i.e., RC parapets) that are integrated with a girder without using any girder-support. GRS integral bridges are basically much more cost-effective in construction and long-term maintenance while having a much higher seismic stability than conventional-type bridges having a girder via movable and fixed supports on a pair of cantilever abutments. GRS integral bridges are better than bridges using GRS retaining walls as abutments and also than conventional integral bridges with unreinforced backfill. To validate the above, a series of static cyclic lateral loading tests of the facing and a series of shaking table tests were performed on smallscaled models of different bridge types.

• Sleep Medicine and Psychophysiology
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• v.7 no.1
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• pp.5-9
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• 2000

Several nonpharmacological treatment methods of insomnia and their effects were reviewed. A long-term use of most hypnotics may produce tolerance, dependence, cognitive and psychomotor impairments at daytime, shallow sleep, and rebound insomnia on drug withdrawal. To reduce hypnotic abuse, nonpharmacological strategies have been developed to correct disordered behavioral and cognitive factors. These treatments aim at modifying maladaptive sleep habits, lowering physiological and cognitive arousal levels, and correcting dysfuctional beliefs and attitudes about sleep. These non-pharmacological or cognitive behavior treatments include stimulus control, sleep restriction, relaxation training, sleep hygiene education, cognitive therapy, and light therapy. Among them the stimulus control therapy has been demonstrated most effective as a single treatment or in combination with other treatments. Through nonpharmacological treatments, sleep latency was most significantly reduced and wake time after sleep onset was also reduced. About 50% of insomniacs reported clinical improvements in terms of nearly normalized sleep latency, awakening time, sleep efficiency, and reduction of hypnotic use. Compared to the hypnotic therapy, nonpharmacological treatments are more cost-effective and more readily accepted by patients, and their effects last longer.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.11a
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• pp.95-100
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• 2000

When compared with conventional retaining wall system, there are many advantages to reinforced soil such as cost effectiveness, flexibility and so on. The use of reinforced soil have been increased in the last 17 years in Korea. In this study, a full-scale reinforced soil with rigid facing were constructed to investigate the behavior of reinforcing system. The results of soil pressure and strain of reinforcement during construction are described. The influence of compaction on soil pressure and strain of reinforcement is addressed. The results show that lateral earth pressures on the wall are active state during backfill. It is obtained that the lateral soil pressure depends on the installation condition of pressure cell and construction condition. It is also observed that maximum tensile strains of reinforcement are located on 50cm to 150cm from the wall. Long-term measurement will be followed to verify the design assumptions with respect to the distribution of lateral stress in the reinforcement

• Proceedings of the KIEE Conference
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• summer
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• pp.677-679
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• 2004

Although Jeju is an island, its electricity demand is 430MW. It indicates electricity demand and its growth rate in Jeju are higher than mainland average. The supply of electricity in Jeju consists of power plants within the island and connection of main system using cable line. The cost of supply is higher than mainland system. However the electricity rate and DSM incentives were treated equally with mainland. Therefore, Effective DSM promotion has not been carried out. This paper analyzes the policy alternatives of supply in Jeju and presents effective DSM countermeasures. Also it presents long-term policy on stabilization of supply and demand in Jeju.

• Proceedings of the KIEE Conference
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• 2000.11a
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• pp.3-5
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• 2000

It has been the paradigm of game theory that more than two utilities compete and determine the price and amount of dispatch. In order for this theory to be available on real power system, it is necessary to consider the transmission costs as well as the generation costs. In addition Independent System Operator(ISO) should be able to mitigate the congestion, recover the transmission costs and provide information for long-term capacity investment by devising reasonable pricing schemes for the transmission services. Generators also have to take the transmission costs into account when building the bidding strategies. This paper proposes an approach to analyzing the profit maximizing game considering the transmission cost in a competitive electricity market.