• Journal of Mechanical Science and Technology
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• 제14권8호
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• pp.807-815
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• 2000

In this paper, modified discrete time preview control algorithms for active and semi-active suspension systems are derived based on a simple mathematical 4 DOF half-car model. The discrete time preview control laws for ride comfort are employed in the simulation. The algorithms for MIMO system contain control strategies reacting against body forces that occur at cornering, accelerating, braking, or under payload, in addition to road disturbances. Matlab simulation results for the discrete time case are compared with those for the continuous time case and the appropriateness of the discrete time algorithms are verified by the of simulation results. Passive, active, and semi-active system responses to a sinusoidal input and an asphalt road input are analysed and evaluated. The simulation results show the extent of performance degradation due to numerical errors related to the length of the sampling time and time delay.

• 가정과삶의질연구
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• 제8권1호
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• pp.69-82
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• 1990

The purposes of this are to figure out the amounts of leisure time of full-time homemakers and to find out leisure time factors contributed to raise the quality of life. The major findings are the followings: 1) Full-time homemakers spend 353 minutes(5.9 hours) on the average per day on the leisure. Time for active leisure(creative activities, sports activities, spectator events, going to the party, and so on) is 70 minutes, while that for passive leisure(watching TV. listening to the radio, reading newspapers. magazines. Books, chating, relaxing, card playing) is 283 minutes(4.7 hours). The passive leisure is the main type of spending leisure time. 2) The total leisure time of wives is significantly related to SES factors. The higher the wives age and education, the family income, and the age of the latest child, the more the wives total leisure time. But the more the family numbers, and the child numbers, the lower the leisure time. Active leisure time is highly rela ed to family income, while passive leisure time is considerably family composition. 3) The wives are mostly satisfied with their lives. The wives perceptions of the quality of life is related to wives's education, house type, and family income. 4) The wives total leisure time is not related to the quality of life. There is a positive correlation between active leisure time and the quality of life, while a negative relationship is between passive leisure time and the perception of the quality of life. 5) In analysis of causal model, it appears that family income and active leisure time of wives directly affect the perceived quality of life. The more the family income and active leisure time, the higher the quality of life. it is implicated for wives to take and active attitude and to reduce, if possible, passive leisure time and to increase active leisure time.

• 전기학회논문지
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• 제66권5호
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• pp.786-791
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• 2017

In this paper, the run time of Li-polymer secondary cell with and without Active Balancing BMS is analyzed. The Active Balancing System using Flyback Converter with two-way power control facility, his designed for optimal characteristics of balancing. The run time of Li-polymer secondary cell is drastically increased employing the Flyback Convert Active Balancing BMS. The run time performance of Li-polymer secondary cell with or without Flyback Converter Active Balancing BMS is analyzed with the discharging and charging experiment of Li-polymer secondary cell.

• 정보처리학회논문지A
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• 제10A권4호
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• pp.295-304
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• 2003

능동객체는 스레드와 같은 독립적인 실행단위로서 객체가 생성될 때 CPU의 스케줄을 받아 실행되어지는 개체이다. 본 논문에서는 이러한 능동객체론 정의하고, 능동객체의 생성 및 실행을 제어하는 능동객체 실행시간 지원시스템(Active object Run Time support systems ; ART)을 제시하였다. 또한 ART는 분산 환경에서 사용자들에게 위치 투명성이 보장되고, 편리한 방식으로 분산 프로그래밍을 할 수 있도록 능동객체 사이에 메소드 호출을 지원할 수 있고, 이를 위한 통신 기법을 설계하고 구현하였다. 그리고 본 논문에서 제안하는 ART를 임베디드 시스템과 같이 시스템 자원이 제한되어 있고, 분산 환경으로 구성되어 있는 시스템에 적용하여 구현하였다.

• 대한본초학회지
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• 제24권2호
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• pp.7-11
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• 2009

Objectives : This research was investigated anticoagulant effect of the Chaenomelis Fructus extract. Methods : To examine an active effect of anticoagulation in Chaenomelis Fructus extract, the study measured Prothrombin time(PT) and activated partial thromboplastin time (APTT) of human plasma in vitro and measured bleeding time and arterio-venous shunt model in rats in vivo. Results : Bleeding time of Chaenomelis Fructus extract in vivo had a significant increase as about 1.6 times and thrombus weight of Chaenomelis Fructus extract had a significant reduction of thrombus weight as 50%. Chaenomelis Fructus extract represented an effect of anticoagulation by operating on extrinsic pathway factor II, V, VII, X and intrinsic pathway factor VIII, IX, X, XI, XII in the coagulation system. Conclusions : Considering the above mentioned results, it is judged that a Chaenomelis Fructus extract has a control effect of thrombus creation.

• Smart Structures and Systems
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• 제16권6호
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• pp.1147-1167
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• 2015

Wireless smart sensors, which have become popular for monitoring applications, are an attractive option for implementing structural control systems, due to their onboard sensing, processing, and communication capabilities. However, wireless smart sensors pose inherent challenges for control, including delays from communication, acquisition hardware, and processing time. Previous research in wireless control, which focused on semi-active systems, has found that sampling rate along with time delays can significantly impact control performance. However, because semi-active systems are guaranteed stable, these issues are typically neglected in the control design. This work achieves active control with smart sensors in an experimental setting. Because active systems are not inherently stable, all the elements of the control loop must be addressed, including data acquisition hardware, processing performance, and control design at slow sampling rates. The sensing hardware is shown to have a significant impact on the control design and performance. Ultimately, the smart sensor active control system achieves comparable performance to the traditional tethered system.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.648-654
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• 2007

This paper presents the result of a comparison study to evaluate the performance of several semi-active control algorithms for use with large-scale MR damper applied to a building structure under seismic excitation using real-time hybrid test method. Recently, a variety of semi-active control algorithm studies are developed and generally evaluated the performance by using numerical analysis. In this paper real-time hybrid test method was applied to performance evaluating of semi-active control algorithms including a clipped optimal algorithm and the modulated homogeneous friction algorithm.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2001년도 추계학술발표논문집 (하)
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• pp.1427-1430
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• 2001

액티브 네트워크는 기존의 패킷 교환 네트워크와 달리 네트워크 중간 노드에서 사용자의 요구나 서비스 특성에 따라 패킷을 처리할 수 있는 차세대 네트워크 구조이다. 기존의 네트워크 문제점을 개선하고 네트워크에 지능을 부여한다는 측면에서 새로운 접근 방식이지만 아직 해결해야 할 많은 논지를 가지고 있다. 본 논문은 액티브 네트워크와 기존의 네트워크 공존문제를 해결, 관리하기 위한 SNMP 확장에 관한 모델을 제시하고, SNMP 기반의 네트워크와 비교 분석하기로 한다.

• 한국정보통신학회논문지
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• 제6권2호
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• pp.356-363
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• 2002

실시간 능통 데이터베이스 시스템은 외부의 환경의 변화에 반응하여 트랜잭션들을 주어진 시간 내에 처리할 수 있어야 한다. 본 논문에서는 Thomas 쓰기 규칙을 적용하여 보다 향상된 실시간 능동 동시성 제어 기법을 제안한다. 제안하는 동시성 제어 기법은 데이터 충돌을 해결하기 위해서 우선순위와 능동 규칙을 고려하여 불필요하게 철회되는 트랜잭션의 수를 감소시킬 수 있다. 본 논문에서는 모의실험을 통해서 제안하는 통시성 제어기법에 의해서 보다 많은 트랜잭션이 종료시한을 만족함을 보인다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.353-354
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• 2014

An active vibration control technique of a time-varying cantilever beam is proposed in this study. A simple in-house coil sensor instead of expensive commercial sensors was used to measure the vibrational displacement of the beam. Active band pass filters and artificial neutral net works detect the frequencies, amplitudes, and phases of the main vibration mode. The time constants of the low pass filter representing the positive position feedback controller are updated in real-time, which generates the control voltage input to actuate the piezoelectric actuator and suppress the vibration. An experiment was successfully performed to verify the algorithm for a cantilever beam, which fundamental natural frequency arbitrarily varies between 9 Hz ~ 18 Hz. The present active vibration suppression technique can be applied to variety of structures which undergoes large variation of dynamic characteristics while operating.