• 설비공학논문집
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• 제13권12호
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• pp.1230-1235
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• 2001

The laminar convection heat transfer in a ventilated space with various horizontal partitions was studied numerically and experimentally. The experimental results by holographic interferometer showed good agreements with the numerical results. For the numerical study, the governing equations were solved by using a finite volume method for $46.6\leqRe\leq1332,\;1460\leqGr\leql1585$, Pr=0.71 and the variations of partition lengths. The isotherms and velocity vectors have been represented for various parameters. As the length of partition increases, the convection heat transfer decreases. Based on the numerical data, a correlation was obtained for the dimensionless mean Nusselt number in terms of $Gr/Re^2$. In the region of $Gr/Re^2$<1, the mean Nusselt number was very small, but in the region of $Gr/Re^2\geq1$, the mean Nusselt number was constant.

• 산업경영시스템학회지
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• 제23권54호
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• pp.1-11
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• 2000

This study suggests the partition algorithm for updating the discovered association rules in large database, because a database may allow frequent or occasional updates, and such update may not only invalidate some existing strong association rules, but also turn some weak rules into strong ones. the Partition algorithm updates strong association rules efficiently in the whole update database reuseing the information of the old large itemsets. Partition algorithms that is suggested in this study scans an incremental database in view of the fact that it is difficult to find the new set of large itemset in the whole updated database after an incremental database is added to the original database. This method of generating large itemsets is different from that of FUP(Fast Update) and KDP(Kim Dong Pil)

• 한국ITS학회 논문지
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• 제20권5호
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• pp.75-82
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• 2021

국내 2020년 기준 교통사고 건수는 약 23만 건으로, 고속도로는 비반복적 정체와 높은 주행 속도로 인해 다른 도로 대비 교통사고 발생 건수당 사망자수가 2배 이상으로 나타나고 있다. 고속도로의 교통정보는 도로의 중심선을 이용한 노드, 링크를 기준으로 제공하고 있으나 세분화된 속도정보를 주지 못하고 있다. 최근 자율주행차 뿐만 아니라 일반 차량에서도 장애물 모니터링, 위치 측정을 위한 차량용 센서 장착이 일반화되고 있어, 대용량 위치 기반 데이터를 이용한 분석은 처리속도에 따라 실시간 서비스가 가능하다. 본 연구는 대용량 위치기반 개별 차량 정보의 분석을 위한 공간 기반의 맵핑 방법을 제시하였다. 경위도 각각 2개로 분할하는 4진법 기준의 분할 방법을 적용하여 개별 차량의 공간 코드를 생성하여 지오코딩 하는 방법으로 처리 속도를 대폭 증가 시켰다. 공간이 세분됨에 따라 평균속도는 유사하였으나 속도의 표준편차는 점차 감소하였으며 9회 분할 이후는 그 감소 폭이 작아 졌다.

• 정보처리학회논문지D
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• 제9D권4호
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• pp.579-586
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• 2002

본 논문은 대용량 주기억장치를 가진 시스템에 적합한 연관 규칙 탐사 알고리즘에 관한 연구이다. 이를 위하여 먼저 기존의 잘 알려진 알고리즘인 DHP, Partition 방법을 대용량 주기억장치를 가진 시스템에서 효율적으로 동작하도록 확장하였고, 다음 Partition 방법에 대해서 해쉬 테이블과 비트맵 기법을 적용하여 Partition 방법을 개선하는 방법을 제안하였다. 제안된 알고리즘은 실험적 환경에서 DHP와 성능이 비교되었으며, 제안하는 알고리즘이 확장된 DHP보다 최대 65%까지 성능 개선 효과가 있음을 보인다.

• 대한기계학회논문집B
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• 제31권6호
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• pp.522-530
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• 2007

The practical studies on the method of particle contamination control for yield enhancement in the cleanroom were carried out. The method of the contamination control was proposed, which are composed of data collection, data analysis, improvement action, verification, and implement control. The partition check method and the composition analysis for data collection and data analysis were respectively used in the main board and the cellular phone module production lines. And these methods were evaluated by the variation of yield loss between before and after improvement action. In case that the partition check method was applied, the critical process step was selected and yield loss reduction through improvement actions was observed. While in case that the composition analysis was applied, the critical sources were selected and yield loss reduction through improvement actions was also investigated. From these results, it is concluded that the partition check and the composition analysis are effective solutions for particle contamination control in the cleanroom production lines.

• 한국화재소방학회논문지
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• 제34권2호
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• pp.14-21
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• 2020

본 논문은 ISO 9705 2/5축소모델 2개를 실내 공간구획에 사용되는 경량칸막이를 이용하여 구획 한 후 ISO 9705 시험을 재현하여 이면부로의 화재위험성에 관한 연구이다. 실험 시료는 시공 시 가장 많이 사용되고 있는 SGP 칸막이, 스터드 칸막이, 그라스울 패널, 우레탄폼 패널, 샌드위치 패널, 유리 칸막이를 선정 하였고, ISO 9705시험 기준에 따라 버너에 점화 전 측정 장치와 데이터의 기록을 시작하여 120 s간 유지시켜 안정화를 취하고, 점화 후 600 s 동안 100 kW, 이후 600 s 동안 300 kW까지 증가하였다가 종료 후 180 s동안 관찰하여 이면부로의 화재 위험성 및 벽체의 화재 패턴을 분석하였다. 점화원에서 발생된 열량으로 인한 최대 이면온도는 SGP 칸막이 67.7 ℃, 스터드 칸막이 55.1 ℃, 그라스울 패널 52.4 ℃, 샌드위치 패널 727.4 ℃, 우레탄폼 패널 561 ℃, 유리 칸막이 630.5 ℃로 측정되었다. 샌드위치 패널과 우레탄폼 패널의 경우 내장재에 용융으로 인한 가연성 가스의 폭발 현상이 발생하였고 강화유리는 수열부와 비수열부의 온도차이로 인하여 유리가 파열되며 인접구획실로의 화재 위험성이 높은 것으로 판단된다.

• Communications for Statistical Applications and Methods
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• 제12권2호
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• pp.497-508
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• 2005

This paper aims at studying on K-means Clustering focusing on initialization which affect the clustering results in K-means cluster analysis. The four different methods(the MA method, the KA method, the Max-Min method and the Space Partition method) were compared and the clustering result shows that there were some differences among these methods, especially that the MA method sometimes leads to incorrect clustering due to the inappropriate initialization depending on the types of data and the Max-Min method is shown to be more effective than other methods especially when the data size is large.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제53권10호
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• pp.530-538
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• 2004

A electromagnetic waves are used for sensing in insulation diagnosis at electric machine or equipment. When it a method, waves are transformed into the FFT(Fast Fourier Transform); a kind of the process for data transformation. In a general way, a scientist use frequncy band 30[㎒]～l[㎓] to applied field. If we are measured high frequency band, we will need to a high capacity hardware. Also a antenna has a fault on atmospheric phenomena, outside environment and the like. In this paper We proposed new method for detecting electric equipment faulty state using only electric voltage which is generally measured in the electric and electronic field. It is called the Partition-FFT The analytic method is this first divide measured voltage waves into equal parts, second each deal with give effect to the FFT, finally each results deal with a graphic method and gather graphic. We are compare Partition-FFT with discharge form by tracking tester. As the result it demonstrated that the Partition-FFT is applicable.

• 한국대기환경학회지
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• 제26권1호
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• pp.77-84
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• 2010

The diffusion and partition coefficients of polyurethane foam (PUF) are estimated using a microbalance experiment and small chamber test. The microbalance is used to measure sorption/desorption kinetics and equilibrium data. When the diffusion condition is controlled in the chamber of the sample, interactions between volatile organic compounds (VOCs) and PUF can lead to the estimation of a relatively homogenous rate of mass transfer in the interiors and surfaces of PUF. The estimates of the material/air partition coefficient (K) and the material-phase diffusion coefficient (D) are shown to be independent of the concentrations of VOCs. This approach, if applied to a diffusion-controlled or physically-based model, can facilitate more precise prediction of their source/sink behavior. Although further research and more rigorous validation is needed, an emission model applied with the diffusion and partition coefficients from this research holds promise for the improvement of reliability in predicting the behavior of VOCs emitted from porous building materials by D and K.

• 한국실내디자인학회논문집
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• 제22호
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• pp.16-22
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• 2000

The purpose of this study is to analyze characteristics of set-booth in beauty salon as well as to suggest the basic design data for franchise beauty salon. The method of this research was based on field observation of the franchise beauty salon in Seoul. The results of this research are as follows. 1) In set-booth type analysis, set-mirror wall type and set-mirror partition type are mainly used, but set-mirror table type is not showed in this research. 2) In terms of scale, wall type and partition type are classified as large scale, wall type and partition type are used as meduim scale. In shop front analysis, the result is shown in two things. If it is type, they used partition type and if it is close type, they used wall type. 3) Set-mirror is consisted of mirror and drawer and it is classified by 4 types with combination method. In a result, most of them used separated mirror type because they want to emphasize the separation between set booth and its layout. 4) Lighting method has 4 types; corniced type, bracket type, pendant type and downlight type. Among them, downlight is showed as the most-used.