• Advances in Energy Research
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• 제2권1호
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• pp.11-20
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• 2014

This paper examines the climatic and technical feasibilities of zero energy buildings in Seoul, Shanghai, Singapore and Riyadh. Annual and seasonal energy demands of office buildings of various scales in the above cities were compared. Using optimally tilted rooftop PV panels, solar energy production potentials of the buildings were estimated. Based on the estimates of onsite renewable energy production and building energy consumption, the energy self-sufficiencies of the test buildings were assessed. The economic feasibilities of the PV systems in the four locations were analyzed. Strategies for achieving zero energy buildings are suggested.

• 한국조리학회지
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• 제10권1호
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• pp.128-139
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• 2004

Korea goes on speedily an information-oriented world in the whole filed of society by diffusing the information-oriented education for the whole nation and the utilization of information. Consequently foodservice enterprise which is establishing their homepage in the web site for marketing purpose and direct application of restaurant management had been increased at recently for the restaurant's publicity, raising their image. The purpose of this study is to examine the feasibilities of internet application in the foodservice industry. Now the generation who most use the internet went into gear the generation of main consumers out of foodservice industry. Also teenagers who occupied the most portions of using internet are able to be the most important potential customer at present or in the near future. Therefore if marketing activity is recognized for this potential customer, it will be more effective than any other way to promotion.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1996년도 재료학회 춘계학술발표회
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• pp.10-10
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• 1996

• International Journal of Automotive Technology
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• 제8권4호
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• pp.429-436
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• 2007

In this study, we improved control performance of an EMV (electromechanical valve) system using a PM/EM (permanent magnet/electromagnet) hybrid EMA (electromagnetic actuator) and showed the feasibilities of both soft landing and fast transition of the EMV system using a simple PID control. The conventional EMV systems using only EM show significant nonlinear characteristics. Therefore, it is very difficult to control the valve position and several complex control schemes are used. This paper focused on the control performance improvement using a PM/EM hybrid actuator. In particular, a PM is used as a key design parameter such as a bias current of a magnetic bearing in order to improve the linear characteristic of the actuator, although most PM/EM hybrid actuators use a PM as a power saver during valve-open and -closed states. First, a FE (finite element) analysis was performed to confirm its linear static force characteristics. Then, both a test rig and a valve control system were built in order to prove experimentally the control performance improvement of the actuator. Finally, feasibilities of both soft landing and fast transition of the system were shown experimentally through gain-scheduled PID (proportional derivative integral) control.

• 한국정보시스템학회지:정보시스템연구
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• 제26권4호
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• pp.137-161
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• 2017

Purpose In this study, the difficulties were analyzed with the field data from two domestic and interview with industry practitioners. And We presented initiatives with feasibilities to overcome the hurdle for progress of easy-payment. Design/methodology/approach We collected industry data from two domestic credit card companies and analyzed that data to prove 7 proposition in detail. Also We had interview data from industry practitioners who can understand the relationship between stakeholders. For this analysis, we used the causal loop diagram to find activation inhibition and activation elements about easy-payment. Findings The Fintech easy-payment industry has been organically involved in various partners such as customers, merchants, PGs, VANs, credit card issuers, banks, payment providers, terminal manufacturers, etc. and they have been competing against each other to hold leader position in the easy-payment market. Because of the reasons, the easy-payment does not spread out as much as it expects. In this study, the difficulties were analyzed with the field data and interview with industry practitioners and proposed five initiatives with feasibilities to overcome the hurdle for progress of easy-payment. This study helps to understand current situation and issues of Fintech and easy-payment for related research in future.

• 한국작물학회지
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• 제30권1호
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• pp.20-25
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• 1985

수도품종 "밀양 23호"를 공시하여 이앙밀도를 달리하면서 재배중의 작업단계별 노동요구도와 수도수량성 및 노동생산성의 변동특성을 조사하였다. 노동요구시간 자체는 표준밀도(22.22주/$m^2$)에서10a당 144시간을 소요하였으나 $m^2$당 밀도를 15.15, 11.11, 8.33주로 감소시킴에 따라 각각 129.116.104시간으로 줄어들었다. 따라서 표준에 대비하여 각각10, 20, 28%의 시간절감이 되었으며, 이앙작업 자체만의 시간에서는 각각 28, 39, 61%의 절감이 가능하였다. 수도수량성에 있어서는 소식에 따른 수량저하를 감소화하고, 보완효과의 최대화를 전제로 하여 $m^2$당12주까지의 일차적인 밀도감소의 한계목표을 설정할 수 있었다. 노동생산성에 있어서는 $m^2$당 11주까지의 소식화로 생산성 향상을 극대화할 수 있을 것으로 판단되었으며, 이들의 종합적 결론을 위하여 품종.시비 및 밀도간의 상호작용 특성에 대한 추후의 연구가 요구되는 것으로 판단되었다.것으로 판단되었다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
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• pp.336-340
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• 2001

In a digital system, there are inevitable delays in calculations and applying the inverter output voltages to the motor terminals. Because of the delays, the conventional predictive current controller implemented in the digital system has large overshoot and large harmonics. A new predictive current controller, considering the delays, for a permanent magnet synchronous motor (PMSM) is presented. The effectiveness and feasibilities are shown by experimental results.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.1335-1341
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• 2011

Conserving clean air and removing contaminants and particular matters accumulated in the ventilation system of the subway stations are key issue for green railway environment. There is no national guideline or industrial regulations to sustain clean duct and ventilation system, which requires rapid reformation of cleaning procedure and system. In fact, accumulated various particular matters and dusts can occur secondary air contamination and become a primary health harm factor for subway passengers. This study investigates various duct cleaning technologies and trends. In additon, effective cleaning method with an automated robot device is proposed. In particular, current dust cleaning technologies and duct cleaning robots are analyzed based on their functions and feasibilities. The proposed design of automated device is expected to save the operating cost of subway HVAC system and sustain clean air environment.

• Journal of Electrical Engineering and Technology
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• 제12권1호
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• pp.173-181
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• 2017

In this paper, the bifurcation criteria for inductive power transfer (IPT) systems is suggested considering the inductive power pad losses. The bifurcation criteria for series-series (SS) and series-parallel (SP) topologies are derived in terms of the main parameters of the IPT system. For deriving precise criteria, power pad resistance is obtained by copper loss calculation and core loss analysis. Utilizing the suggested criteria, possibility of bifurcation occurrence can be predicted in the design process. In order to verify the proposed criteria, 50 W IPT laboratory prototype is fabricated and the feasibilities of the switching frequency and AC load resistance shift to escape from bifurcation are identified.

• 대한전기학회논문지:시스템및제어부문D
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• 제53권1호
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• pp.16-21
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• 2004

This paper presents an approximation method for simplifying a high-order transfer function to a low-order transfer function. A model reduction is based on minimizing the error function weighted by the numerator polynomial of reduced systems. The proposed methods provide better low frequency fit and a computer aided algorithm that estimates the coefficients vector for the numerator and denominator polynomial on the simplified systems from an overdetermined linear system constructed by frequency responses of the original systems. Two examples are given to illustrate the feasibilities of the suggested schemes.