• ETRI Journal
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• 제33권2호
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• pp.176-183
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• 2011

This paper presents a new analytical approach and experimental verification for the improvement of noise performance in phased-array receivers. For analysis purposes, a multi-channel array system is converted into an equivalent single-channel system, such that the two presents the identical signal and noise powers at the output, respectively. We define an effective gain, noise figure, and signal-to-noise ratio in the equivalent system. Through the proposed approach, the noise performance of the array receiver is analyzed in a general and straightforward manner and then compared to that of each individual array channel. In addition, the phase noise of the array system is analyzed in a rigorous manner, showing its effective reduction by a factor of the array size. The predicted improvement of the noise performance is experimentally confirmed with a CMOS integrated phased-array receiver.

• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 1998년도 The 12th Asia Quality Management Symposium* Total Quality Management for Restoring Competitiveness
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• pp.180-187
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• 1998

This paper is to reduce implementation time of POS system by applying QFD. All the related elements are classified by the hierarchical structure into three phases: expected quality, weight and evluation. The mentioned about includes the first and second improvement, and the case study of POS system of petrol stations in Taichung. The results of this research are shown in the following. 1. the first improvement was from average 76 days/station to 48 days/station. 2. the second improvement was from average 48 days/station to 36 days/station. 3. the ratio of target achievement was $162\%$

• 대한전기학회논문지
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• 제39권2호
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• pp.164-174
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• 1990

The improvement of linearized characteistics of induction motor control system with field oriented method is presented in this paper. A fully digitally controlled induction motor driver system based on the proposed linear control condition is described. The control system consists of IBM-PC/AT microcomputer, VSI PWM Inverter, and PI controller with softwave. By controlling the torque component, the rated flux component can be kept constant, even in the transient state. It is clearly confirmed by experiment that the improvement of the vector control condition is satisfactory. A simplified control model of an induction motor similar to the model for a separately excited DC motor drive system is obtained.

• 대한기계학회논문집A
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• 제28권9호
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• pp.1422-1428
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• 2004

In this paper, computer simulation model of handrail band including pulley-driving system is developed to calculate handrail slippage. This handrail simulation model is validated with test result within operating range and used to predict its slippage behavior with respect to variation of 4 different design parameters considering the applicability into the real handrail system. Based upon this parameter study, optimal condition for handrail slippage improvement is proposed without time-consuming and costly experiments of the real handrail system. And then performance improvement of handrail slippage complied with safety code is achieved after applying the optimal condition into the real handrail band system.

• 반도체디스플레이기술학회지
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• 제16권3호
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• pp.8-13
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• 2017

In this paper, the measurement of the inner diameter dimension of the circular hole by using a machine vision system was studied. This paper was focused on the theory and key technologies of machine vision inspection technology for the improvement of measurement accuracy and speed of the micro circular holes. A new method was proposed and was verified through the experiments on Gray conversion, binarization, edge extraction and Hough transform in machine vision system processes. Firstly, the Hough transform was proposed in order to improve the speed increase and implementation ease, it demonstrated the superiority of Hough transform and improvement through a comparative experiment. Secondly, we propose a calibration method of the system in order to obtain exactly the inner diameter of the circular hole. Finally, we demonstrate the reliability of the entire system as a MATLAB-based implementation of the GUI program, measuring the inner diameter of the circular hole through the circular holes of different dimensions measuring experiment.

• Asian-Australasian Journal of Animal Sciences
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• 제5권3호
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• pp.411-418
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• 1992

Recently, onset of bacterial disease, especially infiltration of chronic respiratory diseases have been increasing at high rate. The main cause of these diseases are originated from inappropriate sanitary management and slow progress in introducing system and herd free system, which are the base of productivity improvement in bigger pig management, Methods for the prevention and removal of these diseases, are divided into four categories. The first category includes prevention and removal of infectious diseases by organizing strict animal quarantine, enforcing vaccination, and legal regulation and disposal at the time of outbreak. The second category includes improvement of production systems. This purpose can be achieved by discontinuing the open herd system, which brings on the invasion of foreign pathogens and replacing the system by the closed type of farm. To Continue eradication process step-wisely by performing the all-in all-out system at every pig pen or herd level is also effective for this purpose. The third category includes introduction of herd free system can be achieved by repopulating conventional pigs with SPF pigs. If these means are unrealizable from economic or technical viewpoint, medicated early weaning system is perfomed. This system consists of disinfection of pigsty at pre-postpartum stage, application of drugs to pregnant sows and newborn piglets in accordance with the medication program, and early weaning and rearing of newborn piglets in isolation. The fourth category is sanital leading by veterinarians, aimed to eliminating incentives for diseases through diagnoses. Their main activities include periodical monitoring and improvement leading on each responsible subject.

• 한국기록관리학회지
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• 제15권1호
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• pp.29-52
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• 2015

이 연구는 표준기록관리시스템의 개선전략을 제안하고자 하는 목적으로 수행되었다. 표준RMS의 활용현황 조사 설문지의 개방형 응답이나 면담 내용을 분석하여, 표준RMS를 도입하여 얻은 이점과 활용하지 않는 이유를 도출하였다. 그리고 인수부터 공개관리까지 표준RMS의 9가지 대기능별로 활용과 관련한 쟁점사항도 정리하였다. 마지막으로 (1) 기본 기능 중심으로 개선, (2) 사용자지원과 소통 강화, (3) 생산기관과 국가기록원 간 신뢰 구축, 그리고 (4) 기록과 메타데이터 품질 확보 등 네 가지 개선전략을 제안하였다.

• 전기학회논문지
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• 제64권7호
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• pp.1019-1025
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• 2015

The performance requirements on the safety-based functionality of railway signal systems have been reinforced and the effort for enhancement of the existing system or development of the new system is being accordingly made. In particular, various technical researches on replacement or improvement of the existing ATS(Automatic Train Stop) signaling system are now in progress for better operational efficiency. In this study, the complementary points for improvement or replacement of the currently used system(i.e., ATS) will be derived in terms of operating efficiency in an integrated operating environment with the newly introduced system(e.g., ATC: Automatic Train Control). This study can contribute to derive the need for improvement of the signaling system by checking the interface problems and comparing between different systems through the analysis of real operation cases in the field. Eventually, this analysis can be applied to prevent and estimate the collision accidents can be caused by the failure of the signaling system in advance. In addition, the results can be used to provide a future direction to secure the reliability in the parallel operation by integration based on different railway signaling systems.

• 융합보안논문지
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• 제13권5호
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• pp.167-176
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• 2013

본 연구는 경비지도사 자격제도 개선과 관련하여 현재 경비지도사 업무를 수행하고 있는 경비지도사를 대상으로 NVivo 10을 활용하여, 첫째, 경비지도사 자격시험제도의 문제점, 둘째. 경비지도사 직무교육 문제점, 셋째, 경비지도사 기본 및 보수교육의 문제점에 대하여 고찰하였다. 이들 문제점과 관련된 개선방안을 제시하였다.

• 대한안전경영과학회지
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• 제6권2호
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• pp.231-239
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• 2004

To keep an enterprise's competitiveness on the condition of the automatic manufacturing system such as FA, FMS and CIM, all the maintenance problems should be considered seriously in not only in production and maintenance but also in related industrial productivity. This paper presents the study of equipment reliability improvement for rotary-machine vibration analysis. Based on these analyses, the maintenance management information system, and the machinery condition diagnosis technique are studied by using of the real-time diagnostic. Therefore, it is expected to improve the efficiency of business processes in the production and safety when we use this system.