• 대한수학회보
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• 제53권1호
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• pp.103-117
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• 2016

Abstract. In this paper, we study a modified stochastic predator-prey system with general ratio-dependent functional response. We prove that the system has a unique positive solution for given positive initial value. Then we investigate the persistence and extinction of this stochastic system. At the end, we give some numerical simulations, which support our theoretical conclusions well.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1993년도 춘계학술대회논문집; 한국과학연구소, 21 May 1993
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• pp.101-106
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• 1993

A new rotor control scheme, the isotropic control of anisotropic rotor bearing system in complex state space, is proposed, which utilizes the concepts on the eigenstructure of the isotropic rotor system. Then the control scheme is applied to an active magnetic bearing system and the control performance is investigated in relation to control energy, transient response, and unbalance response. In particular, it is shown that the proposed method is efficient for control of unbalance response.

• 생물정신의학
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• 제20권3호
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• pp.66-73
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• 2013

Sexual behavior is crucial in life, yet comparatively little is known about the mechanisms in the sexual response in humans. A lot of theories and models have been developed to explain about the process of the sexual response in humans. The first model of sexual function was described by Masters and Johnson, defined the four-phase model (phases of excitation, plateau, orgasm and resolution). Helen Kaplan proposed a slightly different model of human sexual response by adding the conception of the desire phase. Some years later, a new model of circular sexual response pattern was described by Whipple and Brash-McGreer, who acknowledged the cyclic nature of women's sexual response. Basson presented an alternative model of women's normative sexual function, which featured a responsive form of desire in women's sexual response. Bancroft developed a new theoretical model, the Dual Control Model, which postulates sexual response and arousal is ultimately determined by the balance between the sexual activation or excitation system and the sexual inhibition system. The Sexual Tipping Point is a model created by Perelman, suggesting that a sexual response is determined by a balance between excitatory or inhibitory factors that may be psychological, organic, psychosocial, or cultural. A comprehensive understanding of sexual response and function is of paramount importance for the psychiatrist to study sex, offer counseling to the patient on sex, and practice sex therapy. In this literature, models of sexual response would be reviewed to understand the knowledge of the sexual functioning in humans.

• 한국공작기계학회논문집
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• 제12권1호
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• pp.92-100
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• 2003

Using a quarter car model, an analytic method for performance estimation of a vehicle suspension system with respect to frequency response, RMS response and performance index is presented. From frequency response function, compromization of response performance to the whole frequency range is verified and from RMS response and performance index, sensitivity of ride md handling characteristics are examined. Using a full car model, sweet area(stable ride area) are determined and performance sensitivity is estimated according to the change of feedback gains. In order to esimate the output sensitivity, response we is displayed using a 3-dimensional contour plot. Design data n suggested for optimal design parameter esimation, which maximize the performance of the given suspension system.

• 전기학회논문지
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• 제63권8호
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• pp.1116-1120
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• 2014

With the shift of the energy paradigm from supply side management to demand side management, demand resource management and demand response plays an important role in the energy industry. As a consequency, a lot of researches have been done to provide a suitable demand response system. However, most of the demand response systems are based on the propriety products that cannot be modified. In this paper, we are proposing an automated demand response system using an EnerNOC provided open source code. We implemented the demand response server (VTN) and demand response client (VEN), and validated the OpenADR2.0 compliances using the open source code. We also used an Arduino microcontoller to demonstrate the communication schemes to control various devices.

• 한국소음진동공학회논문집
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• 제20권10호
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• pp.915-922
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• 2010

This paper presents an efficient method for determining the forced response of a spinning flexible disk-spindle system supported by fluid dynamic bearings(FDBs) in a computer hard disk drive(HDD). The spinning flexible disk-spindle system is represented by the asymmetric finite element equations of motion originating from the asymmetric dynamic coefficients of the FDBs and the gyroscopic moment of a spinning disk-spindle system. The proposed method utilizes only the right eigenvectors of the eigenvalue problem to transform the large asymmetric finite element equations of motion into a small number of coupled equations, guaranteeing the accuracy of their numerical integration. The results are then back-substituted into the equations of motion to determine the forced response. The effectiveness of the proposed method was verified by comparing it with the responses from the classical methods of mode superposition with the general eigenvalue problems, and mode superposition with modal approximation. The proposed method was shown to be effective in determining the forced response represented by the asymmetric finite element equations of motion of a spinning flexible disk-spindle system supported by FDBs.

• 한국지리정보학회지
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• 제11권4호
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• pp.182-192
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• 2008

효율적인 방제전략 수립 지원시스템 개발의 일환으로 환경민감정보 기반의 유출유 확산예측 시스템과 피해위험도 예측시스템을 연계하여 인천-대산해역을 대상으로 해양오염 방제지원시스템의 프로토타입을 개발하였다. 유출유 확산예측시스템에서는 실시간 바람과 실시간 해수유동을 기반으로 유출유의 이동을 계산하고, 유출유 특성에 따라 해상 유출유의 풍화작용을 모델링하여 유출유의 잔류량 및 확산분포를 계산하였다. 유출유 확산예측의 실시간 바람은 국립환경과학원의 실시간 기상모델 결과를 ftp를 이용하여 실시간으로 연계하여 활용하며, 실시간 해수유동으로서 조류는 수치모델결과와 검조소 관측결과의 결합을 통해 실시간 조석을 예측하는 CHARRY(Current by Harmonic Response to the Reference Yardstick) 모델을 이용하여 예측하고, 실시간 취송류는 바람과 취송류간의 상관관계와 반응함수를 이용하여 예측하였다. 실시간 해수유동을 따라 이동하면서 풍화되는 유출유의 풍화작용은 유출유 특성에 따라 결정된 감소율을 적용하여 모델링하였다. 본 시스템은 GIS 기술을 이용하여 해양 정보를 ESI(Environmental Sensitivity Index) 및 방제자원 정보와 통합하고 종합적으로 제공함으로써 방제전략 수립을 지원할 수 있다.

• 한국항해항만학회지
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• 제35권9호
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• pp.735-740
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• 2011

It is necessary to develop the one stop system in order to protect our marine environment rapidly from oil spill accident. The purpose of this study is to develop real time database for oil spill prediction modeling and implement real time prediction modelling with ESI and server-client GIS based user interface. The existing oil spill prediction model cannot provide one stop information system for public and government who should protect sea from oil spill accident. The development of multi user based information system permits integrated handling of real time meteorological data from external ftp. A server-client GIS based model is integrated on the basis of real time database and ESI map to provide the result of the oil spill prediction model. End users can access through the client interface and request analysis such as oil spill prediction and GIS functions on the network as their own purpose.

• 한국방재안전학회논문집
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• 제7권2호
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• pp.35-41
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• 2014

지하철과 같은 지하공간에서 재난이 발생할 경우, 신속하게 안전한 대피 경로로 승객을 유도하여 인명피해를 최소화 하여야 한다. 이를 위해서 빠르게 재난을 감지하고 중앙관리센터에서 신속한 대응이 이루어지지 않는 경우에 자율적으로 의사결정을 할 수 있는 분산형 방재 시스템이 필요하다. 본 연구에서는 분산 자율형 방재 시스템과 재난전조 감지에 관한 개념적인 연구를 수행하였다.

• Nuclear Engineering and Technology
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• 제31권6호
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• pp.586-594
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• 1999

To limit both the large displacement and acceleration response of the structure efficiently, the relationships between acceleration and displacement responses of the structure under several earthquakes are investigated for various horizontal stiffness of the base isolation system to determine the effective stiffness of the base isolation system in this paper. An example structure is a five-storey steel frame building as the primary structure and the secondary structures are assumed to be located on the fifth floor of the primary structure. Input motions used in the structural analysis are El Centre 1940, Taft 1952, Mexico 1985, San Fernando 1971 Pacoima Dam, and artificially generated earthquakes. The relationships of the absolute peak acceleration and the displacement at the top of the structure are calculated for various natural periods of base isolators under various earthquakes. The peak acceleration response of the fifth floor in the base isolated structure is significantly reduced by a factor of 2.1 through 6.25. Also, the relative displacement response of the floor to the base of the superstructure is very small. The results of this study can be utilized to determine the effective stiffness of the base isolation system.