• 제목/요약/키워드: Data Placement

검색결과 628건 처리시간 0.022초

장애인의 인간공학적 직무적정배치 평가 모델에 관한 연구 (A Study on Propriety of Ergonomics Placement Model for Handicapped People)

  • 김현우;고태민;박해천
    • 대한안전경영과학회지
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    • 제9권2호
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    • pp.71-83
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    • 2007
  • This study created a computerized information system of the collected job analysis data and analyzed the computerized job analysis data to derive critical job factors. Based on the ratings on each critical job factor, possible employment opportunities for the various types of disability could be derived according to the match between job condition and handicap condition. The results can be utilized by the Employment and Vocational Training Administration to expand both the counselor and counselee's perspectives about job possibilities and job requirements.

사용자 위치정보를 사용하지 않는 헬퍼 간 중첩 커버리지 영역을 위한 펨토-캐싱 파일 분배 기술 (Femto-Caching File Placement Technique for Overlapped Helper Coverage Without User Location Information)

  • 심재남;민병윤;김동구
    • 한국통신학회논문지
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    • 제39A권11호
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    • pp.682-689
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    • 2014
  • 모바일 데이터 트래픽(data traffic)의 증가로 인해 스몰셀(Small Cell) 가용을 이용한 여러 기술들이 해결책으로 제시되고 있다. 하지만 이러한 기술은 백홀(backhaul) 용량의 증가가 필수적이고 이가 충족되지 않을 경우 성능한계가 기인한다. 이를 바탕으로 기지국 내 헬퍼(helper)라는 백홀 용량이 없거나 작은 대신 저장 매체 용량을 지닌 스몰셀을 이용해 백홀 용량을 저장 매체 용량으로 대체하여 사용자의 데이터 다운로드 지연값을 줄이는 펨토-캐싱(Femto-Caching)이 제시되었다. 본 논문은 사용자 위치 분포를 이용하는 실제적인 시나리오에서 각 헬퍼에 파일 분배 전략 방법을 제시함으로써 기존 연구를 확장하였다. 시뮬레이션을 통해 헬퍼간 커버리지(Coverage)가 겹치는 상황과 헬퍼의 커버리지가 증가하는 상황에 대해 사용자의 데이터를 헬퍼로부터 받을 수 있는 기회가 증가함을 통해 성능을 검증하였다.

반복측정 자료에서 개체기울기를 이용한 집단간의 차이 검정법 (Trend Comparison of Repeated Measures Data between Two Groups)

  • 황금나;김동재
    • 응용통계연구
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    • 제19권3호
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    • pp.565-578
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    • 2006
  • 의약학 분야에서는 두 집단에서 하나의 반복요인을 가지는 반복측정 자료가 많이 사용된다. 이 논문에서는 반복측정된 자료에서 두 군의 시간에 따른 반응값의 선형추세를 비교하여 두 집단간의 차이를 검정하는 방법을 제안한다. 각 개체에서 회귀계수를 추정하고 추정된 회귀계수들에 의해 생성된 표본을 가지고 이표본 t검정(unpaired t-test), 윌콕슨 순위합 검정(Wilcoxon rank sum test), 위치검정(placement test)으로 두 집단간 기울기의 차이를 검정한다. 모의실험(Monte Carlo Simulation)을 통해 실험유의수준(experimental significance level)과 검정력 (power)을 비교하였다.

A Framework for Wide-area Monitoring of Tree-related High Impedance Faults in Medium-voltage Networks

  • Bahador, Nooshin;Matinfar, Hamid Reza;Namdari, Farhad
    • Journal of Electrical Engineering and Technology
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    • 제13권1호
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    • pp.1-10
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    • 2018
  • Wide-area monitoring of tree-related high impedance fault (THIF) efficiently contributes to increase reliability of large-scaled network, since the failure to early location of them may results in critical lines tripping and consequently large blackouts. In the first place, this wide-area monitoring of THIF requires managing the placement of sensors across large power grid network according to THIF detection objective. For this purpose, current paper presents a framework in which sensors are distributed according to a predetermined risk map. The proposed risk map determines the possibility of THIF occurrence on every branch in a power network, based on electrical conductivity of trees and their positions to power lines which extracted from spectral data. The obtained possibility value can be considered as a weight coefficient assigned to each branch in sensor placement problem. The next step after sensors deployment is to on-line monitor based on moving data window. In this on-line process, the received data window is evaluated for obtaining a correlation between low frequency and high frequency components of signal. If obtained correlation follows a specified pattern, received signal is considered as a THIF. Thereafter, if several faulted section candidates are found by deployed sensors, the most likely location is chosen from the list of candidates based on predetermined THIF risk map.

Discovery of Association Rules Using Latent Variables

  • Park, Hee-Chang;Cho, Kwang-Hyun
    • Journal of the Korean Data and Information Science Society
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    • 제17권1호
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    • pp.149-160
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    • 2006
  • Association rule mining searches for interesting relationships among items in a given large data set. Association rules are frequently used by retail stores to assist in marketing, advertising, floor placement, and inventory control. There are three primary threshold measures in association rule; support and confidence and lift. In the case of appling real world to association rules, we have some difficulties in data interpretation because we obtain many rules. In this paper, we develop the model of association rules using latent variables for environmental survey data.

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Discovery of Association Rules Using Latent Variables

  • Park, Hee-Chang;Cho, Kwang-Hyun
    • 한국데이터정보과학회:학술대회논문집
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    • 한국데이터정보과학회 2005년도 추계학술대회
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    • pp.177-188
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    • 2005
  • Association rule mining searches for interesting relationships among items in a given large data set. Association rules are frequently used by retail stores to assist in marketing, advertising, floor placement, and inventory control. There are three primary threshold measures in association rule; support and confidence and lift. In the case of appling real world to association rules, we have some difficulties in data interpretation because we obtain many rules. In this paper, we develop the model of association rules using latent variables for environmental survey data.

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2.4GHz 무선 채널 특성을 가진 센서 노드의 최적 배치 (Optimal Placement of Sensor Nodes with 2.4GHz Wireless Channel Characteristics)

  • 정경권;엄기환
    • 전자공학회논문지CI
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    • 제44권1호
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    • pp.41-48
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    • 2007
  • 본 논문은 2.4GHz 무선 채널 특성을 가진 센서 노드의 손실 없는 데이터 전송을 위한 최적의 배치 방법을 제안한다. 제안한 방식은 무선 환경에서 log-normal path loss 모델을 구성하여 최적의 송수신 거리를 결정하고, 센서 노드의 밀도 계산을 통해서 최적의 센서 노드 개수를 구한다. 데이터 손실이 없는 전송을 위해 송수신 가능 거리와 센서 노드의 개수를 이용하여 공간에 최적으로 배치할 수 있는 위치를 SOM(Self-Organizing Feature Maps)으로 탐색한다. 논문에서 실험한 건물에서는 센서노드의 송수신 거리는 20m이고, 최적의 센서 노드 개수는 8개가 되었으며, 시뮬레이션을 통해서 센서 노드의 최적의 위치 탐색과 센서 노드의 연결 상태를 확인하였다.

Analyzing Online Fake Business News Communication and the Influence on Stock Price: A Real Case in Taiwan

  • Wang, Chih-Chien;Chiang, Cheng-Yu
    • Journal of Information Technology Applications and Management
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    • 제26권6호
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    • pp.1-12
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    • 2019
  • On the Internet age, the news is generated and distributed not only by traditional news media, but also by a variety of online news media, news platforms, content websites/content farms, and social media. Since it is an easy task to create and distribute news, some of these news reports may contain fake or false facts. In the end, the cyberspace is full of fake or false messages. People may wonder if these fake news actually influence our decision making. In this paper, we discussed a real case of fake news. In this case, a Taiwanese company used some fake news, advertorial news, and news placement to manipulate or influence its stock price and trade volume. We collected all news for the case company during a period of four years and five months (from January 2013 to May 2017). We analyzed the relationship between published news and stock price. Based on the analysis results, we conclude that we should not ignore the influence of news placement and fake business news on the stock price.

BGA형 반도체 패키지의 위치정렬용 영상처리기법 오차의 통계적 분석 방법 (A Statistical Analysis Method for Image Processing Errors in the Position Alignment of BGA-type Semiconductor Packages)

  • 김학만;성상만;강기호
    • 제어로봇시스템학회논문지
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    • 제19권11호
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    • pp.984-990
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    • 2013
  • Pick and placement systems need high speeds and reliability for the position alignment process of semiconductor packages in picking up and placing them on placement trays. Image processing is usually adopted for position aligning where finding out the most suitable method is considered most important aspect of the process. This paper proposes a method for judging the performance of different image processing algorithms based on the PCI (Process Capability Index). The PCI is an index which represents the error distribution acquired from many experimental data. The bigger the index, the more reliable the results or the lower the deviation. Two compared and candidate methods are Hough Transform and PCA (Principal Component Analysis), both of which are very suitable for oblong or rectangular type packages such as BGA's. Comparing the two approaches through a CPI with enough experimental results leads to the conclusion that the PCA is much better than the Hough Transform in not only reliability, but also processing speed.

Efficient Idle Virtual Machine Management for Heterogeneous Cloud using Common Deployment Model

  • Saravanakumar, C.;Arun, C.
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권4호
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    • pp.1501-1518
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    • 2016
  • This paper presents an effective management of VM (Virtual Machine) for heterogeneous cloud using Common Deployment Model (CDM) brokering mechanism. The effective utilization of VM is achieved by means of task scheduling with VM placement technique. The placements of VM for the physical machine are analyzed with respect to execution time of the task. The idle time of the VMis utilized productively in order to improve the performance. The VMs are also scheduled to maintain the state of the current VM after the task completion. CDM based algorithm maintains two directories namely Active Directory (AD) and Passive Directory (PD). These directories maintain VM with proper configuration mapping of the physical machines to perform two operations namely VM migration and VM roll back. VM migration operation is performed from AD to PD whereas VM roll back operation is performed from PD to AD. The main objectives of the proposed algorithm is to manage the VM's idle time effectively and to maximize the utilization of resources at the data center. The VM placement and VM scheduling algorithms are analyzed in various dimensions of the cloud and the results are compared with iCanCloud model.