• 품질경영학회지
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• 제29권1호
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• pp.61-84
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• 2001

The problem of trend change in the failure rate is great interest in the reliability and survival analysis. In this paper we develop a test statistic for testing whether or not the failure rate changes its trend based on a complete sample. Monte Carlo simulations are conducted to investigate the speed of convergence of the proposed test statistic.

• 정보와 통신
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• 제9권2호
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• pp.49-59
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• 1992

본 논문에서는 정보공학의 주요 주제를 정하고 이를 조사 분석한다. 특히 정보 통신 분야에서의 산학 협동 방안을 제시한다. 현재의 상황 즉 대학에서의 교육 현황, 인력현황, 연구 개발 동향을 조사하고 장래의 전망에 대해 분석한 후 이의 대처 방안을 제안한다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.1543-1548
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• 2008

Ubiquitous technology is the trend towards increasingly ubiquitous, connected computing devices in the environment, a trend being brought about by a convergence of advanced electronic - and particularly, wireless - technologies and the internet. Ubiquitous technology is pervasive in nature and unobtrusively embedded in the environment, completely connected, intuitive, effortlessly portable, and constantly available. The object of this paper is to describe the strategy plan for Ubiquitous-Urban Transit Total Information System.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 B
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• pp.1027-1029
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• 2000

Electric vehicle(EV), hybrid electric vehicle(HEV) and fuel cell electric vehicle(FEV) are seen as one way of reducing the harmful effects of traffic and of improving energy efficiency. Therefore the status and developing trend of the EV, HEV and FEV are given in this paper. A major aspect of alternative drive trains is the electric drive train. The automotive aspect in developing electric drive trains is emphasized.

• 연구논문집
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• 통권24호
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• pp.141-149
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• 1994

Recently, IVHS technology attracted public attention according as national IVHS project was initiated by SOC. In advanced countries, specially in USA, Europe, and Japan. IVHS technology was already studied for over ten years as national strategic project. In this paper we describe the concept and development trend of AVCS which is a part of IVHS technology. The important contents in AVCS are automatic collision warning and avoidance system, automatic intelligent cruise control system, automatic vehicle platoon control system, automatic lateral control system, etc.

• East Asian mathematical journal
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• 제35권4호
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• pp.489-508
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• 2019

In this paper we used text mining method to analyze journals of mathematics education posterior to the year of 2016. To figure out trends of mathematics education research. we analyzed the key words largely mentioned in the recent mathematics education journals by Term Frequency and Term Frequency-Inverse Document Frequency method. We also looked at how these keywords match up with the key words that appear of education to prepare for future society. This result can infer the characteristics of mathematics education research in the aspect upcoming research topics.

• Journal of the Korean Statistical Society
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• 제15권1호
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• pp.31-45
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• 1986

It is often necessary to obtain some run orders in factorial designs which have a small number of factor level changes and a small linear time trend. In this paper we propose an algorithm to find optimal or near-optimal run orders for $2^4, 2^5, 3^2$ and $2\cdot 3^2$ factorial designs under the criterion that the number of factor level changes and the linear time trend should be simultaneously small.

• 한국정밀공학회지
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• 제10권4호
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• pp.7-15
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• 1993

This paper introduces a new concept to analyze the digital control system where the continuous-time plant is stabilized by the digital controller with sampler and hodl. It gives some methods to handle the inter-sampling behavior which has not been considered in the digital controller design. Also, the new trend and future direction in digital control are introduced.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.2527-2538
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• 2011

The Reliability started for MILitary purposes during World War II in 1942, getting more important for maintenance, safety, etc in modern society. As technologies develop, also international standards for measuring the reliability is advancing. RAMS activities for maintenance, safety verification is material to national railroad. And for this, it needs quick response for the changes of standards. Even now standards are upgrading for developing electronic technologies. Therefore analysis of failure rate's trend about such standards is judged necessary. So We submit a this paper for comparative analysis of changing process standards according to development of electronic technologies and reliability. At first, we compared actual usage ratio of standards for understanding the current state of usage. Based of these state of usage, discuss the major standard. And then, introduced reliability standards's trend, calculation method of failure rate and difference of failure rate calculation standard according to march of time. In this paper, used standards are MIL-HDBK-217F, Telcodia, etc.

• 대한전기학회논문지
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• 제34권10호
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• pp.389-398
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• 1985

Recently maximum power demand of our country has become to be under the great in fluence of electric cooling and air conditioning demand which are sensitive to weather conditions. This paper presents the technique and algorithm to forecast the long-term maximum power demand considering the characteristics of electric power and weather variable. By introducing a weather load model for forecasting long-term maximum power demand with the recent statistic data of power demand, annual maximum power demand is separated into two parts such as the base load component, affected little by weather, and the weather sensitive load component by means of multi-regression analysis method. And we derive the growth trend regression equations of above two components and their individual coefficients, the maximum power demand of each forecasting year can be forecasted with the sum of above two components. In this case we use the coincident dry bulb temperature as the weather variable at the occurence of one-day maximum power demand. As the growth trend regression equation we choose an exponential trend curve for the base load component, and real quadratic curve for the weather sensitive load component. The validity of the forecasting technique and algorithm proposed in this paper is proved by the case study for the present Korean power system.