• Journal of the Korean Society for Precision Engineering
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• v.17 no.7
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• pp.106-112
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• 2000

The purpose of this paper is to study on the control of the engine idle speed under sudden A/C load which is one of the most severe disturbances on engines. Three types of the closed-loop controller are developed for the stable engine idle speed control. The input of the controller is an error of rpm. The output of the controller is an ISCV duty cycle. The anticipation delay is considered to deal with the delay time of the air mass in engine. The PID, Fuzzy and PID-type Fuzzy controllers with the anticipation delay have improved the engine idle speed condition more than current ECU map table under the A/C load.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.3
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• pp.29-36
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• 1998

In recent year, as the demand about low vibration and noise vehicle is increased constantly. automobile companies try to a lot of things to achieve this demand. Gear rattle vibration become an emergency problem to be cured at idling. There are two kinds method to reduce idle gear rattle vibration One is optimization of clutch damper design parameters(stiffness, hysteresis torque, preload, length of lst stage) the other is system parameters modification(inertia, drag torque, backlash, etc) But these methods are impossible to estimate influence rate of each gearpair on the idle gear rattle vibration. In this study, 14degrees of freedom nonlinear model is developed to analyze influnce rate of each gearpair on the idle gear rattle vibration and the counterplan to reduce the gear noise is suggeted through the shift system modification.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.2
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• pp.203-210
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• 2003

A simulation study was carried to analyze the vehicle fuel consumption on component basis. Experiments was also carried out to identify the simulation results, under FTP-75 Hot Phase driving conditions. and arbitrary driving conditions. A good quantitative agreement was obtained. Based on the simulation, fuel energy was used in pumping loss(3.7%), electric power generation(0.7%), engine friction(12.7%), engine inertia(0.7%), torque converter loss(4.6%), drivetrain friction(0.6%), road-load(9.2%), and vehicle inertia(13.4%) under FTP-75 Hot Phase driving conditions. Using simulation program, the effects of capacity factor and idle speed on fuel consumption were estimated. A increment of capacity factor of torque converter resulted in fuel consumption improvement under FTP-75 Hot Phase driving conditions. Effect of a decrement of idle speed on fuel consumption was negligible under the identical driving conditions.

• Proceedings of the KIEE Conference
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• 1994.07a
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• pp.88-90
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• 1994

The permanent magnet type stepping motor is used widly for various devices, such as FA and OA machine. Characteristics of the stepping motor is analyzed using permeance method. Static, dynamic and I step response characteristics of PM type stepping motor for idle air valve is discussed.

• Proceedings of the Korea Information Processing Society Conference
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• 2017.11a
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• pp.70-71
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• 2017

Volunteer Computing은 대규모 프로젝트를 많은 분산된 데스크탑, 랩탑 PC, 그리고 스마트 폰과 같은 모바일 디바이스의 idle(유휴 상태)인 컴퓨팅 자원을 기여(Volunteer)받아 수행하는 환경이다. 그러나 기여된 컴퓨팅 자원이 idle과 used(사용 상태) 간의 상태전이가 빈번히 일어나거나, idle로 지속되는 시간이 짧은 자원의 경우, 프로젝트를 수행하는데 비효율적이다. 따라서 본 논문에서는 이러한 자원을 구분하고, 해당 자원의 다음 상태전이확률테이블을 계산하여 결과에 따라 해당 자원에 적합한 작업을 할당하는 방법을 제안한다.

• Journal of Agricultural Extension & Community Development
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• v.16 no.2
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• pp.439-461
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• 2009

The aim of this study is to make abolished school utilized to be served for promotion of off-farm incomes, vitality of agriculture and rural communities' economic, i.e. directly related in inhabitants' income. The methods of this study was to classify the types of utilization via analysis of abolished school data base which served by Ministry of Education & Human Resources Development. Moreover, we tried to derive problems of management and the existing system via interview survey of the nation's best 100 executives who utilize abolished school and present active factors of abolished school utilization and improvement directions. Then, we classified types of the idle agricultural land utilization into categories and selected the survey site which were the best on the idle agricultural land. Then, we suggests utilization and improvement directions to the use and management of idle agricultural land for increasing inhabitants' income, vitality of agriculture and rural communities' economic.

• Korean Journal of Computational Design and Engineering
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• v.6 no.4
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• pp.244-253
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• 2001

For more complete process planning, machining sequence determination is critical to attain machining economics. Although many studies have been conducted in recent years, most of them suggests the non-unique machining sequences. When the tool approach directions(TAD) are considered fur a feature, both machining time and number of setups can be reduced. Then, the unique machining sequence can be extracted from alternate(non-unique) sequences by minimizing the idle time between operations within a sequence. This study develops an algorithm to generate the best machining sequence for composite prismatic features in a vertical milling operation. The algorithm contains five steps to produce an unique sequence: a precedence relation matrix(PRM) development, tool approach direction determination, machining time calculation, alternate machining sequence generation, and finally, best machining sequence generation with idle times. As a result, the study shows that the algorithm is effective for a given composite feature and can be applicable fur other prismatic parts.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.11 no.17
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• pp.39-46
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• 1988

This Paper is concerned with a man-multi machine assignment problem to minimize idle time. Assuming different types of semi-automatic machines with deterministic service-processing time, the problem approaches by sequential dependent one operator can handle several machines, where determine optimal range the cost of idle labor and machine time is to be minimized in preparing a work schedule. The Procedure, to establish man-machine assignment model, and it's results are: (1) Objective function to minimize opportunity loss cost, which is happened by idle time, is verified recursive process through heuristic method. (2) The algorithm, is programmed by BASIC language for personal computer, and a numerical example is given to illustrate the heuristic algorithm. This study will be helpful to enhance productivity of Shopflooras a result of increasing the efficiencies of both operator and machine.

• The Journal of Engineering Research
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• v.7 no.1
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• pp.29-36
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• 2005

In multi-server environment, We have to design a mechanism that selects appropriate servers for processing each service request while maximizing server throughput and minimizing average response of service requests. In this paper, we propose a job scheduling method for courseware delivery system using a idle computing resources on LAN. The proposed scheduling method propose an approach that uses client service request time, server available period and server load of requested service as guidelines of server selection. Comparing the our approach method to conventional one, experiments that the proposed approach provides better performance.

• Industrial Engineering and Management Systems
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• v.15 no.1
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• pp.1-10
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• 2016

This paper presents a fast sequencing algorithm for a mixed model assembly line with multiple workstations which minimize the total utility work and idle time. We compare the proposed algorithms with another heuristic, the Tsai-based heuristic, for a sequencing problem that minimizes the total utility works. Numerical experiments are used to evaluate the performance and effectiveness of the proposed algorithm. The Tsai-based heuristic performs best in terms of utility work, but the fast sequencing algorithm performs well for both utility work and idle time. However, the computational complexity of the fast sequencing algorithm is O (KN) while the Tsai-based algorithm is O (KNlogN). Actual computational time of the fast sequencing heuristic is 2-6 times faster than that of the Tsai-based heuristic.