• 한국수소및신에너지학회논문집
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• 제20권1호
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• pp.38-44
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• 2009

Recently, the research focused on fuel cell hybrid vehicles (FCHVs) is becoming an attractive solution due to environmental pollution generated by fossil fuel vehicles. The proper energy control strategy will result in extending the fuel cell lifetime, increasing of energy efficiency and an improvement of vehicle performance. Battery state of charge (SoC) is an important quantity and the estimation of the SoC is also the basis of the energy control strategy for hybrid electric vehicles. Estimating the battery's SoC is complicated by the fact that the SoC depends on many factors such as temperature, battery capacitance and internal resistance. In this paper, battery charging time estimated by SoC is studied by using the speed response and current response. Hybrid system is consist of a fuel cell unit and a battery in series connection. For experiment, speed response of vehicle and current response of battery were determined under different state of charge. As the results, the optimal battery charging time can be estimated. Current response time was faster than RPM response time at low speed and vice versa at high speed.

• Structural Engineering and Mechanics
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• 제32권1호
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• pp.179-191
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• 2009

A stochastic response spectrum method is proposed for simple evaluation of the structural response of an actively controlled aseismic structure. The response spectrum is constructed assuming a linear structure with an active mass damper (AMD) system, and an earthquake wave model given by the product of a non-stationary envelope function and a stationary Gaussian random process with Kanai-Tajimi power spectral density. The control design is executed using a linear quadratic Gaussian control strategy for an enlarged state space system, and the response amplification factor is given by the combination of the obtained statistical response values and extreme value theory. The response spectrum thus produced can be used for simple dynamical analyses. The response factors obtained by this method for a multi-degree-of-freedom structure are shown to be comparable with those determined by numerical simulations, demonstrating the validity and utility of the proposed technique as a simple design tool. This method is expected to be useful for engineers in the initial design stage for structures with active aseismic control.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2000년도 봄 학술발표회논문집
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• pp.431-438
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• 2000

The cost function consists of the weighting functions concerning the structural responses to be controlled and the controller capability. Therefore, the control efficiency depends on the characteristics of the weighting functions. The objective of this paper is the comparative study of the time domain control strategies of LQR and LQG and the frequency domain strategy of H₂ by setting the equivalent weighting functions to the all control strategies. As a result of analysis, LQR strategy is found to be more efficient than other strategies in terms of the response reduction. but the control force is found to be a little highter. As LQG can compensate the limitation of LQR that all state variables should be identified, LQG is more acceptable algorithm than LQR. Furthermore LQG shows a good performance both in the response reduction and the control force. Finally H₂ algorithm is employed to illustrate the importance of weighting filters considering the frequency characteristics of the response and the controller. It Is shown that the H₂ algorithm is found to be the most effective one for the response control with a little control force having a low frequency band.

• 월간포장계
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• 통권192호
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• pp.62-69
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• 2009

• 상하수도학회지
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• 제23권2호
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• pp.155-163
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• 2009

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2012년도 춘계학술대회
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• pp.507-509
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• 2012

국제수로기구는 수로정보의 표준화와 활용성 증진을 위해 ISO 19100 시리즈 GIS 표준을 수로분야로 확장한 S-100 표준을 수립하고, 이를 기반으로 한 S-10X 표준을 개발 중에 있다. 국제해사기구는 해사안전과 해양환경 보호를 위해 e-Navigation 전략을 추진 중에 있으며, e-Navigation 전 분야에 대한 정보화 표준 모델인 CMDS를 정의하고 S-100 표준을 기반으로 개발할 계획이다. e-Navigation 전략 추진 대상 영역을 해상부분, 네트워크부분, 육상부분으로 구분할 수 있는데, VTS는 육상 관제센터로서의 핵심적인 역할을 수행하고 있다. 본 연구에서는 S-100 표준 도입이 국제해사기구의 e-Navigation 전략을 통해 VTS에 미치는 영향에 대해 분석하였고, 향후 우리나라 VTS가 e-Navigation 전략 하에서 업무 고도화 및 기능개선을 위한 수로분야 협력방안을 제안하였다.

• 한국콘텐츠학회논문지
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• 제17권11호
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• pp.398-409
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• 2017

기업의 위기 관리와 관련된 상황적 위기커뮤니케이션 이론에서는 위기 유형별로 서로 다른 전략이 사용되어야 한다고 본다. 기업의 책임이 높은 경우에는 사과, 개선 방안 제시 등 순응적 전략을 사용하고, 기업의 책임이 낮은 경우에는 공격, 부인 등 대응적 전략을 사용하는 것이 타당하다고 주장한다. 이에 본 연구에서는 기업에서 실제 홍보 업무를 담당하는 실무자들을 대상으로 설문 조사를 실시하여, 실제 위기 유형별로 사용하는 위기관리 전략에 차이가 존재하는지를 살펴보았다. 홍보 담당자들에 대한 설문조사를 분석한 결과, 실제 기업의 위기 유형별로 위기관리 전략에 차이가 존재 하였다. 기업의 책임이 없는 경우에는 부인 및 공격적 대응 전략이 상대적으로 선호되었고, 기업의 책임이 있는 경우에는 사과 및 개선 전략이 상대적으로 우세하였다. 또한 위기 유형별로 기업 내에서 홍보팀의 역할도 차이가 존재했다. 위기 수준이 높을수록 홍보팀의 역할이 증대되기는 하지만, 의사결정 권한은 약해지는 경향이 있었다. 이러한 본 연구의 결론은 한국에서 위기 관리 전략의 실태를 보다 깊이 있게 이해하는데 기여할 수 있을 것이다.

• Journal of Electrical Engineering and Technology
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• 제9권3호
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• pp.789-795
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• 2014

In a demand response (DR) market run by independent system operators (ISOs), load aggregators are important market participants who aggregate small retail customers through various DR programs. A load aggregator can minimize the allocation cost by efficiently allocating its demand response resources (DRRs) considering retail customers' characteristics. However, the uncertain response behaviors of retail customers can influence the allocation strategy of its DRRs, increasing the economic risk of DRR allocation. This paper presents a risk-based DRR allocation method for the load aggregator that takes into account not only the physical characteristics of retail customers but also the risk due to the associated response uncertainties. In the paper, a conditional value-at-risk (CVaR) is applied to deal with the risk due to response uncertainties. Numerical results are presented to illustrate the effectiveness of the proposed method.

• The International Journal of Costume Culture
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• 제7권2호
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• pp.123-134
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• 2004

This study tried to suggest the effective future marketing strategies by analysing marketing strategies of five brands which were selected by sales amount and the growth rate among young casual brands in the L-Department store from 2001 to 2002. According to analysis, brand marketing could summarize to five marketing strategies such as culture marketing, emotion marketing, co-marketing, on-line marketing, and propose marketing. Culture marketing includes 'BB family marketing, star marketing, core marketing, experience marketing. One of the emotion marketing is 'Kidult marketing' which affects cute concept. Co-marketing includes 'Charisma marketing' that cooperates with distribute industry, 'Movata marketing' which cooperates with mobile communication industry, and 'Game marketing' which cooperates with game industry. There are some other marketing strategies such as consumer calling marketing, A.S.A. marketing which is for buyers, QR marketing for quick response, Web site's differentiate marketing and Logo marketing. The suggested marketing strategies for on-coming brands are 'distinguished strategy of the online contents', 'consumer calling strategy' and 'loyalty maximizing strategy'.

• ETRI Journal
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• 제31권5호
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• pp.622-624
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• 2009

This letter presents a compact 2.5 Gb/s burst-mode receiver using the first reported monolithic amplifier IC developed with 0.25 ${\mu}m$ SiGe BiCMOS technology. With optimum avalanche photodiode gain, the receiver module can obtain a fast response, high sensitivity and wide dynamic range, satisfying the overhead timing and various power specifications for a 2.5 Gb/s next-generation passive optical network (PON), as well as a legacy 1.25 Gb/s PON in the upstream.