• 한국도서관정보학회지
• /
• 제25권
• /
• pp.83-107
• /
• 1996

The purpose of this study is to experiment online public access catalog enhancements to improve its subject access capability. Three catalog databases, enhanced with title keywords, controlled vocabulary, and content words with controlled vocabulary respectively, were implemented. 18 searchers performed 2 subject searshes against 3 different catalog databases. And the transaction logs are analyzed. The results of the study can be summarized as follows : Controlled vocabulary catalog database achieved 41.8% recall ratio in average ; the addition of table of contents words to the controlled vocabulary is an effective technique with increasing recall ration upto 55% without decreasing precision ; and the database enhanced with title keywords shows 31.7% recall ratio in average. Of the three kinds of catalog databases, only the catalog with contents words produced 2 unique relevant documents. The results indicate that both user training and system development is required to have better search performance in online public access catalog.

• 한국콘텐츠학회:학술대회논문집
• /
• 한국콘텐츠학회 2004년도 추계 종합학술대회 논문집
• /
• pp.157-161
• /
• 2004

본 연구는 레이저빔을 제어하기 위한 전자 셔터의 디지털 I/O 인터페이스와 온도 제어 알고리즘을 개발함으로써 레이저 치료 시 열적 피이드백을 통한 치료의 가능성을 제시하였다. 이러한 전자셔터 구동 인터페이스와 제어 알고리즘의 개발로 어느 일정한 범위의 온도가 자동제어 되도록 설계하였다.

• 한국전산유체공학회:학술대회논문집
• /
• 한국전산유체공학회 2008년도 춘계학술대회논문집
• /
• pp.126-129
• /
• 2008

In this study the aerodynamic characteristics of a canard-controlled missile with freely spinning tailfins were investigated by using a CFD code. The aerodynamic coefficients and roll-rate of freely spinning tailfins were calculated by an analysis of 6-DOF and the Euler code. Results were in good agreement with experimental data, and the roll-rates of freely spinning tailfins were also in good agreement with the experimental data for the roll and yaw canard control inputs. This indicates that the CFD Euler code can be applied to predict the canard-controlled missile with freely spinning tailfins.

• 한국산업융합학회 논문집
• /
• 제18권1호
• /
• pp.30-36
• /
• 2015

This paper presents the theoretical development of a complete navigation problem of a nonholonomic mobile robot by using ultrasonic sensors. To solve this problem, a new method to computer a fuzzy perception of the environment is presented, dealing with the uncertainties and imprecision from the sensory system and taking into account nonholonomic constranits of the robot. Fuzzy perception, fuzzy controller are applied, both in the design of each reactive behavior and solving the problem of behavior combination, to implement a fuzzy behavior-based control architecture. The performance of the proposed obstacle avoidance robot controller in order to determine the exact dynamic system modeling system that uncertainty is difficult for nomadic controlled robot direction angle by ultrasonic sensors throughout controlled performance tests. In additionally, this study is an in different ways than the self-driving simulator in the development of ultrasonci sensors and unmanned remote control techniques used by the self-driving robot controlled driving through an unmanned remote controlled unmanned realize the performance of factory antomation.

• 대한기계학회논문집A
• /
• 제20권8호
• /
• pp.2501-2507
• /
• 1996

In this paper actively controlled air bearing is investigated to overcome the defects of air bearing such as low stiffness and damping coefficients. The actively controlled air beairng is composed of an air bearing, a gap sensor, a controller, and a piezo actuator. By controlling the position of air bearing with piezo actuator, the position of floating object is controlled. In this study the proportional-Integral-Derivative controller is employed. Active air bearing is investigated numerically and experimentally. There is good agreement between the simulation and the experimental results. It is shown that the stiffness and damping characteristics and positioning experimental results. It is shown that the stiffness and damping characteristics and positioning accuracy of air bearing can be improved by means of adopting actively controlled air bearing.

• 한국항공운항학회지
• /
• 제27권3호
• /
• pp.106-111
• /
• 2019

Pilot has been fighting to get over fatigue during flight and thought it as a hinderance for safe flight. The fatigue related problem has been the biggest obstacle for aviation safety so far. Even though pilots and airlines try their best to overcome fatigue during flight, they couldn't overcome this problem. So the airliners let the pilot sleep during flight if pilots are too tired with the report. It is controlled rest used and managed by several European airliners. So this study tries to get Korean airline pilots' fatigue information and figure out the cause and reduce it.

• 시스템엔지니어링학술지
• /
• 제18권2호
• /
• pp.40-49
• /
• 2022

Remote-controlled and autonomous driving based on artificial intelligence are key elements required for unmanned combat vehicles. The required capability of such an unmanned combat vehicle should be expressed in reasonable required operational capability(ROC). To this end, in this paper, the requirements of an unmanned combat vehicle operated under a manned-unmanned teaming were analyzed. The functional requirements are remote operation and control, communication, sensor-based situational awareness, field environment recognition, autonomous return, vehicle tracking, collision prevention, fault diagnosis, and simultaneous localization and mapping. Remote-controlled and autonomous driving of unmanned combat vehicles could be achieved through the combination of these functional requirements. It is expected that the requirement analysis results presented in this study will be utilized to satisfy the military operational concept and provide reasonable technical indicators in the system development stage.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2017년도 추계 학술논문 발표대회
• /
• pp.183-184
• /
• 2017

Some of the information created during the design phase of an New NPP life cycle is useful only for the execution of the construction phase; however, much of the information greatly impacts the longer-term operational phase. To most make use of design and construction information produced by data based design system during the construction and operation phase, This research is identified controlled data and drawn design information of controlled equipment from documents generated during the life-cycle stages. This study aimed to analyze related documents to assure traceability of controlled equipment from design phase through O&M and then suggested DB(Data Base) based control method on technical information of major equipment throughout nuclear power plant lifecycle.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
• /
• 제52권5호
• /
• pp.238-245
• /
• 2003

In this paper, a single Phase voltage source voltage-controlled active power filter(APF) for power quality improvement was proposed. The proposed APF has the performance of harmonic suppression and unity power factor correction. The performance of harmonic suppression can be obtained by controlling the waveshape of the APF output voltage to be sine wave. And, unity power factor is controlled by the reactive power control loop of the APF output. Simulation and experimental results using diode rectifier showed that the voltage-controlled APF, unlike the current-controlled APF, can reduce the voltage harmonics as well as current harmonics. Also the results showed that the input dover factor and power quality were greatly improved.

• Tribology and Lubricants
• /
• 제24권1호
• /
• pp.34-43
• /
• 2008

In this paper, an actively controlled aerostatic bearing is studied to overcome the defects of air bearing such as low stiffness and damping coefficients. The actively controlled aerostatic bearing is composed of aerostatic bearings, non-contact type of displacement sensors, piezoelectric actuators and controllers. The cylindrical capacitance sensor (CCS) is used as the displacement sensor. The reason for using CCS instead of the commercial gap sensor is that it can give us the pure error motion of the spindle because it removes the roundness error or the geometric errors in the spindle. The controller is designed by the state space equation and quadratic optimal control theory. The characteristic data of the actively controlled aerostatic bearing system in the frequency domain are presented and the stiffness and damping coefficients of the bearing are mentioned. This paper shows the possibility to reduce the motion error up to 6000 rpm.