• Journal of Power Electronics
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• 제15권1호
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• pp.39-53
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• 2015

This paper presents the regulation of the output voltage and inductor currents in a Single Ended Primary Inductor Converter (SEPIC), operating in the continuous conduction mode (CCM) using a sliding mode controller. Owing to the time varying nature of the SEPIC converter, designing a feedback controller is a challenging task. In order to improve the dynamic performance of the SEPIC, a Sliding Mode Controller (SMC) is developed. The developed SMC is designed by using a state space average model. The performance of the developed controller with the SEPIC converter is validated at different working conditions through Matlab simulations. It is also compared with the performance while using a PI controller. The results show that the designed controller gives very good output voltage regulation under different operating conditions such as a varying input voltage, changes in the load and component variations. A 48V, 46W experimental setup for has been developed in an analog platform to validate the performance of the proposed SMC.

• 전기학회논문지
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• 제64권1호
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• pp.16-22
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• 2015

As the development of Battery Energy Storage System(BESS) and the increasing of intermittent energy sources like wind power and photovoltaic, the application of BESS in load frequency control is considered as an effective method. To evaluate the effectiveness of BESS application in frequency control, we defined a governor free model of BESS to conduct dynamic simulation. Using the BESS dynamic model, we implemented the power system dynamic model including steam, gas and hydro turbine generators. In this paper we study the control performance of BESS in primary frequency control. The effect of BESS speed regulation rate and response time on governor free operation is investigated. In addition, we compared BESS from steam turbine generator in view point of frequency regulation.

• IMMUNE NETWORK
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• 제12권3호
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• pp.71-83
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• 2012

T cell activation and function require physical contact with antigen presenting cells at a specialized junctional structure known as the immunological synapse. Once formed, the immunological synapse leads to sustained T cell receptor-mediated signalling and stabilized adhesion. High resolution microscopy indeed had a great impact in understanding the function and dynamic structure of immunological synapse. Trends of recent research are now moving towards understanding the mechanical part of immune system, expanding our knowledge in mechanosensitivity, force generation, and biophysics of cell-cell interaction. Actin cytoskeleton plays inevitable role in adaptive immune system, allowing it to bear dynamic and precise characteristics at the same time. The regulation of mechanical engine seems very complicated and overlapping, but it enables cells to be very sensitive to external signals such as surface rigidity. In this review, we focus on actin regulators and how immune cells regulate dynamic actin rearrangement process to drive the formation of immunological synapse.

• 한국시스템다이내믹스연구
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• 제13권4호
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• pp.57-80
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• 2012

This research studies effect of FDA regulations in pharmaceutical industry on new drug development. System dynamics is implemented to demonstrate dynamic relationship between FDA regulations and R&D costs, firm's profits, sales. This research is focused on clinical trials of new medical entity process 50~60% portion of total development cost. Simulation results say that firm's profit is more sensitive to increasing the regulation than alleviating the regulation and effect of regulation policy make different result depending on the intensity of regulation and policy direction. Our simulation model provides the instrumental means for the policy makers and strategic decision in pharmaceutical industry.

• 한국시스템다이내믹스연구
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• 제16권1호
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• pp.53-74
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• 2015

The purpose of this paper is to simulate public trust on nuclear regulation policy. The first of all, public trust variables and the model were developed and analysed by system dynamic method. The model are consisted of the operator safety culture level, regulatory competence levels, the public satisfaction and public trust level. The scenario is made up three type which base scenario, the system operator's safety culture level and accident event level. First. the simulation results of standard scenario shows that rapidly declining public satisfaction and trust level of the national safety after Japan's nuclear accident in November 2011. Second, operator safety culture level and simulated divided into three levels. The results showed that a greater impact on the public satisfaction if bad than good case. Finally, the size of the accident was simulated divided into three levels levels(no accident, medium, serious accidents). the results showed a weak effect against the regulatory capacity and safety performance levels but showed a significant impact on public satisfaction and confidence level.

• Structural Engineering and Mechanics
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• 제58권1호
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• pp.39-58
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• 2016

Since the publication of ACI 318-02, the concrete capacity design (CCD) method has been used to determine the resistance of unreinforced concrete anchors. The regulation of steel-reinforced anchors was proposed in ACI 318-08. Until ACI 318-08, the shear resistance of concrete breakout for an unreinforced anchor during an earthquake was reduced to 75% of the static shear strength, but this reduction has been eliminated since ACI 318-11. In addition, the resistance of a hairpin-reinforced anchor was calculated using only the strength of the steel, and a regulation on the dynamic strength was not given for reinforced anchors. In this study, shaking table tests were performed to evaluate the dynamic shear strength of unreinforced and hairpin-reinforced cast-in-place (CIP) anchors during earthquakes. The anchors used in this study were 30 mm in diameter, with edge distances of 150 mm and embedment depths of 240 mm. The diameter of the hairpin steel was 10 mm. Shaking table tests were carried out on two specimens using the artificial earthquake, based on the United States Nuclear Regulatory Commission (US NRC)'s Regulatory Guide 1.60, and the Northridge earthquake. The experimental results were compared to the current ACI 318 and ETAG 001 design codes.

• Earthquakes and Structures
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• 제6권2호
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• pp.163-179
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• 2014

Dynamic test with scaled model of a group of intake towers was performed to study the dynamic interaction between water and towers. The test model consists of intake tower or towers, massless foundation near the towers and part of water to simulate the dynamic interaction of tower-water-foundation system. Models with a single tower and 4 towers were tested to find the different influences of the water on the tower dynamic properties, seismic responses as well as dynamic water-tower interaction. It is found that the water has little influence on the resonant frequency in the direction perpendicular to flow due to the normal force transfer role of the water in the contraction joints between towers. By the same effect of the water, maximum accelerations in the same direction on 4 towers tend to close to each other as the water level increased from low to normal level. Moreover, the acceleration responses of the single tower model are larger than the group of towers model in both directions in general. Within 30m from the surface of water, hydrodynamic pressures were quite close for a single tower and group of towers model at two water levels. For points deeper than 30m, the pressures increased about 40 to 55% for the group of towers model than the single tower model at both water levels. In respect to the pressures at different towers, two mid towers experienced higher than two side towers, the deeper, the larger the difference. And the inside hydrodynamic pressures are more dependent on ground motions than the outside.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.101-108
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• 2008

The dynamic behavior of railway bridges originates from dynamic properties of various spans and structural types. As a result, the exact estimation of dynamic properties of the railway bridge can produce the exact estimations of dynamic performances of the railway bridge. The damping ratio affects the dynamic reponses of the railway bridge in the vicinity of the critical speed seriously. Eurocode, National Annex of each European country and Japan have their own specification for the damping ratio for the estimation of dynamic performance of railway bridges. In our case, the specification for Honam high speed railways follows the Eurocode. In the present study, for the verification and regulation of the damping ratio and investigation of various dynamic properties, modal tests of various structural types are performed. In addition, for the investigation of effects of track structures on the dynamic property of the bridge, ballast track and concrete track are installed and tested.

• 한국추진공학회지
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• 제8권3호
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• pp.27-36
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• 2004

본 논문에서는 AMESim을 이용하여 터보펌프 모사 장치 중 압력조절계에 대한 시뮬레이션을 수행하였다. 시스템의 최적화를 통하여 압력조절계의 과도 및 정상상태의 특성과 응답성을 확인하였다. 연구결과들은 향후 제어밸브의 성능 검증 및 제어로직 검증을 위한 추력제어시스템 성능 시험장치 및 엔진공급계 인증시험설비의 설계와 운용 시 적극 반영할 계획이다.

• International Journal of Computer Science & Network Security
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• 제22권4호
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• pp.67-72
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• 2022

The main purpose of the study is to analyze the main aspects of state regulation of the banking business in the context of social and digital transformation. One of the key elements of the functioning of the economy of any country are banks that ensure the redistribution of financial resources and stimulate economic growth. However, the banking sector, like other activities, is dynamic and depends on the pace of development and forms of technological progress that affect the forms and types of information and digital technologies, as well as the globalization and remoteness of banking services. Accordingly, the need for effective implementation of the latest technologies becomes relevant, which will not only help increase consumer satisfaction with the banking product, but also ensure the development of the country's financial sector. As a result of the study, trends in the development of state regulation of the banking sector in the digital economy were identified.