• 한국전기전자재료학회논문지
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• 제17권9호
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• pp.973-978
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• 2004

This work describes the effect of conducting materials on the electrochemical performances of electric double layer capacitor. Three kinds of Carbon black, such as Acethylene Black, Super P Black, Ketjen black supplied by Denki Kagaku Kogyo, MMM Carbon, Ketjen Black International Co. respectively, was added in carbon-Polytetrafluoroethylene (PTFE) electrode, which composition is activated carbon : carbon black : PTFE = 80 : 15 : 5 wt.%, and were compared with their electrochemical properties. The electrode with Ketjen Black has showed the lowest resistance than other carbon black, and also exhibited the better rate capability between 0.5 mA/cm$^2$ ∼ 100 mA/cm$^2$ current density in unit cell capacitor. On the other hand, as increasing the composition of Ketjen Black, the specific resistances of electrodes were decreased and Ketjen Black content higher than 15 wt% increased. The best rate capability was obtained at the electrode with 15 wt.% of Ketjen Black in unit cell capacitor. This behaviors would be correlated with the dense structure of electrode.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.746-747
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• 2015

Recently, Korea has achieved accumulated total value of orders of six hundred billion dollars in international construction market, and it is facing a new turning point by entering the overseas construction market. However, according to the statistics on the current internal construction market, the accumulated value of orders has been mainly obtained by plant projects in the Middle-East area. To improve international competitiveness of Korean construction industry, it is required to expand and diversify the target areas and construction business sectors. To expand markets, each construction firm should establish the expansion strategy and assess the capability which includes the strength and weakness of their firm. Therefore, this research aims to evaluate the capability of the Korean construction firms for overseas expansion. Through the research, Korean construction industry is expected to strengthen competitiveness toward the overseas markets. Furthermore, this research contributes to expanding and diversifying markets for domestic construction firms.

• 한국건설관리학회논문집
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• 제14권2호
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• pp.87-95
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• 2013

국내 CM시장이 활성화됨에 따라 경쟁이 심화되어 실제 프로젝트 관리를 담당하는 CM단장의 능력은 CM사업 수주를 위한 중요한 요소가 되었다. 이로 인해 각 CM전문회사는 유능한 CM단장의 확보를 위해 현재 담당 프로젝트가 없더라도 후속 프로젝트의 수주를 위해 CM단장을 일정수 대기상태로 확보하고 있으나, 효율적인 활용방안에 대해서는 체계적인 방법이 마련되지 못한 실정이다. 이에 본 연구는 현재 CM전문회사가 보유하고 있는 대기상태 CM단장들의 활용실태 및 문제점을 분석하고, CM단장의 효율적인 활용을 위한 개선방안을 모색하기 위한 실무적 기초자료를 제시하고자 하였다. 본 연구결과, CM전문회사의 현재 대기상태 CM단장 인력수는 적정 비율 및 인력수에 비해 약 2배 정도 많은 것으로 나타났고, CM단장의 선정기준으로 프로젝트의 수주를 위해 프레젠테이션 능력을 가장 중요한 요소로 고려하고 있었다. 그리고 대기상태 CM단장의 보유 및 활용상 문제점은 크게 고용비용 증가와 현장 및 본사 업무지원능력 부족 및 제한적 활용으로 요약되었고, 대기상태 CM단장의 효율적인 활용을 위한 현장 및 본사 기술지원과 수주능력 강화 및 제도개선 등에 관한 개선방안을 제안하였다.

• 한국수소및신에너지학회논문집
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• 제6권1호
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• pp.43-52
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• 1995

Hydrogen storage alloy powder compacts were prepared by using automatic press, with PTFE as a binder. Hydrogen absorption and desorption characteristics and thermal conducting property of the compacts were studied using test hydrogen cylinder, comparing with bare alloy powder. The compacts showed better rate capability and activation characteristics than bare powder. Effective thermal conductivity and diffusivity of the compact bed were $1.0{\times}10^{-2}W/cmK$ and $2.0{\times}10^{-2}cm^2/S$, respectively, which were similar to that of bare powder bed. A good rate capability of the compacts was interpreted in terms of hydrogen permeation rather than thermal conductivity in the beds.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.513-516
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• 2001

In this study, the properties of MCMB anode Mixed with KCF were evaluated, KCF material was used as not only conducting agent but also active material, The Electirc conductivity of MCMB and KCF were 23.7S/cm and 45.8S/cm. Characteristics of anode with different KCF contents were the best effect at 2wt%. The 1st Ah efficiency of cells were increased with increment of KCF contents. The internal resistance and the rate capability were $1.59{\Omega}$ and 135mAh/g at 2C, The discharge capacity was gradually faded with the charge-discharge cycling to about 50th cycles.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.513-516
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• 2001

In this study, the properties of MCMB anode Mixed with KCF were evaluated. KCF material was used as not only conducting agent but also active material. The Electric conductivity of MCMB and KCF were 23.7S/cm and 45.8S/cm. Characteristics of anode with different KCF contents were the best effect at 2wt%. The 1st Ah efficiency of cells were increased with increment of KCF contents. The internal resistance and the rate capability were 1.59Ω and 135mAh/g at 2C. The discharge capacity was gradually faded with the charge-discharge cycling to about 50th cycles.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 가을 학술논문 발표대회
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• pp.240-241
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• 2021

For the sustainable development of the domestic construction project management field, each CM company should try to diversify in terms of service contract types and scope of work while having internationally competitive technical and service capabilities as follows. First, from the initiation of the service to the completion, the CMr should be able to establish and execute a plan to create specific outcomes. Second, CMr must have the capability to produce weekly or monthly cost, schedule, risk, and scope management reports. In addition, it should be possible to apply the cost plus sliding fee method or to systematically and continuously accumulate and process data generated during the construction process.

• 대한토목학회논문집
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• 제31권1D호
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• pp.99-109
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• 2011

국민경제에 상당한 비중을 차지하는 건설산업에 대하여 적정수준의 경기 유지와 산업의 효율성 개선 및 경제 활성화를 위한 방편으로 민간투자사업이 활성화되고 있다. 최근 민간투자산업이 활성화되면서 민간사업자측에서는 건설사업관리(CM)의 도입을 통한 사업의 성공적 수행을 도모하고 있는 반면, 민간투자사업을 관장하는 주무관청은 민간사업자측에 비해 경험 및 역량이 부족한 실정이다. 이에 본 연구에서는 주무관청의 업무역량을 강화하기 위한 방안으로서 기존의 발주자지원형 CM의 업무확장의 개념으로 기존의 CM의 업무체계를 유지하면서 주무관청을 적극적으로 지원하기 위한 파트너쉽지원관리 (Partnership Support Management; PSM) 방식을 도입하기 위하여 민간투자사업의 추진단계를 사업개발단계, 사업고시단계, 사업평가단계, 사업협약단계 및 변경협약단계의 5단계로 분류하여 PSM 참여가능시점 및 유형과 이해관계자의 상관성을 고려한 PSM 업무수행구조와 업무프로세스를 제안하였다. 본 연구에서 제안된 PSM 업무모델은 주무관청의 업무이해도를 향상하여 업무역량 강화 및 업무 부담을 경감시켜, 민간투자사업의 추진을 효율적으로 수행할 수 있을 것으로 기대된다.

• 한국재료학회지
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• 제32권5호
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• pp.270-279
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• 2022

In this study, N/S co-doped carbon felt (N/S-CF) was prepared and characterized as an electrode material for electric double-layer capacitors (EDLCs). A commercial carbon felt (CF) was immersed in an aqueous solution of thiourea and then thermally treated at 800 ℃ under an inert atmosphere. The prepared N/S-CF showed a large specific surface area with hierarchical pore structures. The electrochemical performance of the N/S-CF-based electrode was evaluated using both 3-electrode and 2-electrode systems. In the 3-electrode system, the N/S-CF-based electrode showed a good specific capacitance of 177 F/g at 1 A/g and a good rate capability of 41% at 20 A/g. In the 2-electrode system (symmetric capacitor), the freestanding N/S-CF-based electrode showed a specific capacitance of 275 mF/cm² at 2 mA/cm², a rate capability of 62.5 % at 100 mA/cm², a specific power density of ~ 25,000 mW/cm² at an energy density of 23.9 mWh/cm², and a cycling stability of ~ 100 % at 100 mA/cm² after 20,000 cycles. These results indicate the N/S co-doped carbon felts can be a promising candidate as a new electrode material in a symmetric capacitor.

• Journal of Electrical Engineering and Technology
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• 제13권6호
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• pp.2145-2157
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• 2018

Congestion Management (CM) is an attractive research area in the electrical power transmission with the power compensation abilities. Reconfiguration and the Flexible Alternating Current Transmission Systems (FACTS) devices utilization relieve the congestion in transmission lines. The lack of optimal power (real and reactive) usage with the better transfer capability and minimum cost is still challenging issue in the CM. The prediction of suitable place for the energy resources to control the power flow is the major requirement for power handling scenario. This paper proposes the novel optimization principle to select the best location for the energy resources to achieve the real-reactive power compensation. The parameters estimation and the selection of values with the best fitness through the Symmetrical Distance Travelling Optimization (SDTO) algorithm establishes the proper controlling of optimal power flow in the transmission lines. The modified fitness function formulation based on the bus parameters, index estimation correspond to the optimal reactive power usage enhances the power transfer capability with the minimum cost. The comparative analysis between the proposed method with the existing power management techniques regarding the parameters of power loss, cost value, load power and energy loss confirms the effectiveness of proposed work in the distributed renewable energy systems.