• 경영정보학연구
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• 제17권3호
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• pp.113-133
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• 2015

본 논문은 BI 시스템을 도입하여 사용하고 있는 기업들을 'IT통신 업종', '전기전자 업종', '에너지 화학 업종', '자동차 기계 장비 업종', '식품 소비재 업종' 과 같이 5개 산업 업종으로 구분 하여 BI 시스템을 도입한 기업의 효율성을 DEA 기법의 CCR 모형과 BCC 모형을 활용하여 평가하였으며, 특히 Time-Window 기법을 적용하여 BI 도입 후 기간별로 효율성의 변화 추이를 분석하였다. 즉 BI 시스템을 도입한 기업들의 상대적인 효율성을 비교하여 순위를 매기고, 분석 시 BI 도입 시점으로부터 시간이 흐른 것을 토대로 비교 평가하는 Time Window 기법을 활용하여 BI를 도입한 지 오래된 기업과 그렇지 않은 기업을 차별화하여 의미 분석하였다. 분석 결과는 에너지 화학 산업에서 BI 도입 후 효율성 제고가 두드러졌고 전기 전자 산업의 효율성이 꾸준히 안정화되어 가고 있는 것으로 분석되었다.

• 한국통신학회논문지
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• 제30권4C호
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• pp.185-190
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• 2005

IS-95와 IMT-2000 시스템에서 사용되고 있는 여러 종류의 길쌈 부호기를 부호율 1/2, 구속장 3인 길쌈 부호기로 한정하여, 비터비 복호기에 복호길이 6인 Sliding-Window와 Neural Network의 LVQ(Learning Vector Quantization)및 PVSL(Prototype Vectors Selecting Logic)을 적용하여 순방향 실시간 복호기를 구현한다. 이론적으로 제한된 AWGN 채널환경에서의 심볼 전송전력 $S/(N_{0}/2)=1$을 성능비교 조건으로 하여 순방향 실시간 복호기와 기존의 비터비 복호기의 $강\cdot연판정$ BER 성능과 하드웨어 구성을 $비교\cdot분석$하여, 본 논문에서 제시된 순방향 실시간 복호기의 BER 성능의 우수성과 비화통신의 장점 및 하드웨어 구성의 단순합을 검증하였다.

• 정보처리학회논문지C
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• 제9C권5호
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• pp.743-748
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• 2002

최근 인터넷에서 QoS(Quality of Service)를 제공하는 방법인 차별 서비스에 대해 많은 연구가 진행중이다. 차별화 서비스에서 보장형 서비스는 2등급 패킷 폐기 우선순위 방법과 RIO(RED with In and Out)를 일반적으로 사용한다. 하지만 이 방법만으로는 대역폭을 만족할 만큼 공평하게 사용자에게 제공하지 못한다. 본 논문에서는 공평성을 개선하기 위한 방법으로 TSW(Time Sliding Window) marking algorithm을 개선하여 TS2W3C(Time Sliding Two Window Three Color)marking algorithm을 제안한다. ns-2를 이용하여 제안된 메커니즘을 모의 실험을 통해 성능을 분석한 결과, 제안한 방법이 기존의 방법에 비해 공평하게 대역폭을 분배하는 것으로 나타났다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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• pp.222-226
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• 2009

The parts of building which has the most influence on thermal load are skins, outer walls and windows. Among them, window is the worst weak point of building even if it has many advantage of solar radiation gain than other parts. The present time, many researches on various performance of window and many types of system-window are being made. This study evaluates thermal performance of tilt & sliding system window by simulation program Therm 5.2 and Window 5.2. After making a sample model improving it's thermal weak point, this study evaluates real thermal performance of system window. As a result, this study understands manufacture ability condition of domestic company and proposes a research plan of system window.

• 대한수학회지
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• 제51권5호
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• pp.897-918
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• 2014

This paper addresses multi-window Gabor frames with rational time-frequency product. Such issue was considered by Zibulski and Zeevi (Appl. Comput. Harmonic Anal. 4 (1997), 188-221) in terms of Zak transform matrix (so-called Zibuski-Zeevi matrix), and by many others. In this paper, we introduce of a new Zak transform matrix. It is different from Zibulski-Zeevi matrix, but more direct and convenient for our purpose. Using such Zak transform matrix we characterize rational time-frequency multi-window Gabor frames (Riesz bases and orthonormal bases), and Gabor duals for a Gabor frame. Some examples are also provided, which show that our Zak transform matrix method is efficient.

• 한국소음진동공학회논문집
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• 제20권6호
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• pp.568-576
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• 2010

It is widely known that the leak locating of underground plastic pipelines is much more difficult than that of cast iron pipelines. The precision of the leak locating depends upon the speed of leak signal and the time delay estimation between the two sensors on the pipeline. In this paper, six different windowing filters are considered to improve the time delay estimation especially for the plastic pipelines. The time delay is usually estimated from the peak time of cross-correlation functions. The filtering windows including rectangle, Roth, Wiener, SCOT, PHAT and maximum likelihood are applied to derive the generalized cross-correlation function and compared each other. Experimental results for the actual plastic underground water supply pipeline show that the introduction of the filtering windows improved the precision of time delay estimation. Some window functions provide excellent leak locating capability for the plastic pipe of 98 m long, which is less than 1 % of the pipe lengths. Also a new probabilistic approach that the combinations of all results from each filtering window is suggested for the better leak locating.

• 정보과학회지
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• 제5권2호
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• pp.49-60
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• 1987

待期 理論(Queuing, waiting-Line Theory)은 例을 지어 待期하고 있는 現 象, 즉 各種 窓口에서 特定의 서어비스를 提供받기 위하여 個體가 기다리는 現象 에 관한 理論이며, 이와같은 理論的인 現象을 待期行列現象(Queuing phenomena, Waiting-Line phenomena)이라고 한다.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2023년도 춘계학술발표대회
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• pp.377-379
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• 2023

Concept drift detection on data stream is the major issue to maintain the performance of the machine learning model. Since the online stream is to be a function of time, the classical statistic methods are hard to apply. In particular case of seasonal time series, a novel window strategy with Fourier analysis however, gives a chance to adapt the classical methods on the series. We explore the KS-test for an adaptation of the periodic time series and show that this strategy handles a complicate time series as an ordinary tabular dataset. We verify that the detection with the strategy takes the second place in time delay and shows the best performance in false alarm rate and detection accuracy comparing to that of arbitrary window sizes.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.737-740
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• 1999

This paper deals with a real time optimization algorithm within real time for DRGS(Dynamic Route Guidance System) and evaluate the algorithm. A pre-developed system offers the optimal route in using only static traffic information. In using real-time traffic information, Dynamic route guidance algorithm is needed. The serious problem in implementing it is processing time increase as nodes increase and then the real time processing is impossible. Thus, in this paper we propose the optimal route algorithm with window mechanism for the real-time processing and then evaluate the algorithms.

• 한국실내디자인학회논문집
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• 제18권5호
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• pp.101-110
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• 2009

In case of general residential house, photovoltaic can be installed at roof, wall, and any other places. But, in case of apartment building, there has not enough roof space to install photovoltaic panels to supply enough electricity. Actually, apartment building roof and facade wall (exclude the balcony window space) is not enough space to produce and supply the electricity to residents by installing PV panel. Generally, the space of facade balcony with windows in facade wall at apartment building occupied about $70{\sim}80%$, in all facade space. So, if we could use the balcony and windows space in facade as PV to generating electricity, there could contribute the energy saying. But, PV cell is opacify. So if it installed at front window area in apartment building, residents may have displeasure for that opacity character. But the other hand, residents are not always in house especially in day time that is exactly good time for generating electricity by PV. If we can use PV at the facade balcony with window without collusion of resident's displeasure, there have good attraction to using sustainable energy. Hence, this study suggests the design of facade balcony window style PV by considering resident's living pattern in apartment building. The methods of this study are as follows. At first, this study surveyed to the residents about residential time in their home and asked user demand by Delphi survey. At second, this study designed balcony open style PV system which oriented to the user demand. At third, this study tests designed result performance by computer simulation that compared design result with old design. As a result, For the purpose of satisfying the resident demand, there designed sliding window style which slide the several door systems to the one side. That would be make balcony absolute open scenery to the residents. Hence, the designed system performance results were as follows. When we compare the small apartment and large apartment, smaller one has good performance than larger one. Because resident's residential time characteristic. And that has more good electronic performance than vertical style that is similar to roof style.