• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전력기술부문
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• pp.284-286
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• 2003

The low load power factor causes various problems such as the Increase of the power loss and the voltage instability. The demand of reactive power increases continuously with the growth of active power and the restructuring of electric power companies makes the integrated management of ractive power troublesome, from which the systematic control of load power factor is required. In this paper, the load power factor sensitivity of the generation cost and integrated costs are used for determining the locations and capacities of reactive power compensation devices effectively and for enhancing the load power factor appropriately. It is shown through the application to a small-scale power system that the system power factor can be enhanced effectively and appropriately using the load power factor sensitivity and integrated costs.

• 전기학회논문지
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• 제66권12호
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• pp.1705-1711
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• 2017

This paper analyzes the impact of DRA (Demand Response Aggregator) on market power when competing with power generation companies (Gencos) in the electricity market. If congestion occurs in the transmission line, the strategic choice of the power generation company increases exercise of market power. DRA's strategic reduction of power load impacts the strategy of Gencos, which in turn affects the outcome of the load reduction. As the strategy of Gencos changes according to the location of the congested transmission line, the impact on the market depends on the relative location of the congested line and the DRA.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2008년도 정보통신설비 학술대회
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• pp.304-308
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• 2008

The standardization for Seamless IP Mobility between heterogeneous networks is being progressed according to each specific purpose of the organizations such as ITU-T (International Telecommunications Union - Telecommunication), 3GPP(3rd Generation Partnership Project), IETF(Internet Engineering Task Force), and IEEE(Institute of Electrical and Electronics Engineers). [1] Specially VCC (Voice Call Continuity) for seamless voice continuity between heterogeneous networks using IMS (IP Multimedia Subsystem) of the next generation platform is being introduced into a few companies, and also MIH (Media Independent Handover) and MIP (Mobile IP) for IP mobility between heterogeneous networks are being customized by their internal situation. This article describes the idea to support IP Mobility between heterogeneous networks in the network which IMS platform is deployed and only supports the mobility for the voice by the type of AS (Application Server).

• International Journal of Internet, Broadcasting and Communication
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• 제13권1호
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• pp.69-81
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• 2021

While the fifth generation (5G) and beyond 5G (B5G) mobile communication networks are being rolled over the globe, several world-wide companies have already started to prepare the sixth generation (6G). Such 6G mobile networks targets ultra-reliable low-latency communication (URLLC). In this paper, we challenge to reduce the inherent latency of existing non-orthogonal multiple access (NOMA) in 5G networks of massive connectivity. First, we propose the novel unipodal binary pulse amplitude modulation (2PAM) NOMA, especially without SIC, which greatly reduce the latency in existing NOMA. Then, the achievable data rates for the unipodal 2PAM NOMA are derived. It is shown that for unequal gain channels, the sum rate of the unipodal 2PAM NOMA is comparable to that of the standard 2PAM NOMA, whereas for equal gain channels, the sum rate of the unipodal 2PAM NOMA is superior to that of the standard 2PAM NOMA. In result, the unipodal 2PAM could be a promising modulation scheme for NOMA systems toward 6G.

• 한국의상디자인학회지
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• 제24권3호
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• pp.111-125
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• 2022

Recently, the MZ generation has been leading overall fashion trends, and fashion companies focus on design, marketing, and new products targeting the MZ generation. However, it is expected that a fit problem may occur if the M and Z generations are combined when producing clothing. Therefore, this study aims to analyze the differences between the two groups by comparing the body size according to the classification of the M and Z generations. In addition, this study analyzes whether the body shape of the MZ generation is different from the past generations and analyzes major changes in body size for clothing manufacturing through graphical visualization. As for the research method, a t-test was conducted to verify the significant difference between the measurements for each age group. Generation M was defined as those who are 27-39 years old, and Generation Z was defined as those who are 20-26 years old. In order to examine the changes in body measurements according to the measurement year, the 7th Size Korea and 8th Size Korea data were analyzed. In order to examine the visual changes according to the measurement year and age group, major measurements of clothing construction were analyzed. As a result, it was found that Generation M had a significantly higher height item than Generation Z. Also, in terms of circumference, width, and thickness, Generation M was larger than Generation Z. But the size of the bra cup was larger in Generation Z than Generation M. As a result of analyzing the body size changes, in the height item, the 8th Size Korea measurements were found to be significantly higher in shoulder height and navel level waist height. In the length and circumference items, the 8th Size Korea measurements were larger than the 7th. In the width, thickness, and other items, the 8th measurements were larger than the 7th.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 춘계학술대회
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• pp.472-475
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• 2005

Genenrally, biogas contained methane contents of $40-75\%$, was made in anaerobic compost facilities, landfill site, etc. And it is very useful for gas engine as a fuel. So, many imported biogas engines for electrical generation, are installed and operating now at landfill sites and anaerobic compost facilites. And KIMM has studied on and developed biogas engines with the aids of engine maker and parts companies for several years. Some results are shown here.

• Journal of Welding and Joining
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• 제20권3호
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• pp.46-53
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• 2002

The expolitation of substitute material and new manufacturing technology of the automobile body panel for next generation cars have been steadily professed by advanced automobile companies. High strength steel of TRIP (Transformation of Induced Plasticity) type is developed in response to demands about crash safety and high strength of automobile. In this study, basic technologies can fix up problems occurring on the mass production and applied to the other forming methods will be prepared through rasping a property of TRIP material.

• 한국막학회:학술대회논문집
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• 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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• pp.3-6
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• 2004

Industrial gas separation by membranes began in 1980 with the introduction of hollow-fiber polysulfone membrane systems by Permea, at that time a division of Monsanto. This first application was the recovery of hydrogen from ammonia reactor purge gas and was soon followed by the generation of nitrogen from air. Today, membrane gas separation ranks second behind cryogenic distillation in terms of nitrogen production, and this application has drawn the industrial gas companies into the membrane field.(omitted)

• 벤처창업연구
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• 제18권4호
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• pp.149-163
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• 2023

혁신클러스터 정책은 특정 지역에 산업부문과 연구부문의 연계를 강화하여 산업의 경쟁력을 확보하는 것을 목적으로 한다. OECD(1997)에서 첨단 중소기업을 중심으로 산업 재구조화를 통해 지역발전을 유도하는 혁신클러스터 개념이 제시된 후 산업과 지역, 과학기술 분야에서 혁신클러스터 개념을 적용하여 적극적으로 정책을 추진하기 시작했다. 혁신클러스터 활성화 차원에서 그간의 정책 및 연구에서는 구성원 간 교류·협력에 집중하는 경향이 뚜렷했으나, 본 연구에서는 혁신클러스터를 육성하고자 하는 근본적인 이유인 산업 및 지역의 경쟁력 강화, 즉 기업의 경쟁력 강화에 집중하여 연구를 진행하였다. 이에 따라, 본 연구는 혁신클러스터 활성화 요인이 대덕연구개발구에 입주한 중소기업의 경영성과에 미치는 영향을 분석하는 것을 목적으로 진행하였다. 이를 위해 혁신클러스터가 가지는 본질적인 개념인 산업집적 요인, 네트워킹 요인, 혁신창출 요인 등 혁신클러스터 활성화 요인 도출 후 175개 기업의 설문조사 결과를 활용하여 가설을 검증하였다. 혁신클러스터 활성화 요인 중 산업집적 요인과 혁신창출 요인은 기업의 경영성과에 긍정적으로 영향을 미치는 것으로 나타났다. 그러나 네트워킹 요인은 기업의 경영성과에 유의한 영향을 미치지 않는 것으로 분석되었다. 본 연구는 이전에 수행된 사례 중심의 연구들과 달리 실증분석을 통해 혁신클러스터의 활성화 요인을 다루었다는 점에서 차별성을 가진다. 또한, 혁신클러스터에서 네트워킹 요인에 대한 직관적 판단과 실제 기업의 경영성과에 미치는 영향 간 차이를 고려하여, 보다 효과적인 혁신클러스터 정책을 위해서는 지역에 뿌리내려진 사회적·문화적 구조, 특화 산업의 특성, 구성원의 니즈 등 다각적인 관점에서 혁신클러스터에 대한 입체적 검토의 필요성을 제기했다는 측면에서 실무적인 의의도 존재한다.

• 한국경영과학회지
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• 제12권1호
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• pp.157-157
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• 1987

Hydro-electric power generation from multi-purpose dams has been playing important roles in the electric power supply network in Korea. Although the total share of hydro power in national electricity supply now becomes very small, the peak-shaving and frequency control capability of hydro power helps the power company enormously in maintaining the quality of power. But since the company that builds and operates the multi-purpose dams in Korea has to sell all the electricity produced to the monopolistic utility, there have been various problems in justifying the investment, designing pricing mechanism, and controlling operations of the power plants. In addition, economic evaluation of the hydro power has been distorted by a variety of reasons and hence it has been very difficult to encourage effective development and utilization of national water resources. To make the problem worse, both parties are public companies with X-inefficiency problems. Thus, changing environment requires to reengineer the system that governs hydro power generation. We address the problems of Korean hydro-electric power generation system in four areas: the investment justification process, the operations decison right of the hydro power plants, the pricing of the purchased-power, and the negotiation of contract revision. Then we propose improvement directions of new hydro-electric power system in view of static and dynamic efficiency, X-inefficiency and equity.