• Title/Summary/Keyword: average distance

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Analyzing the Impact of Inventory Management Performance on the Energy Efficiency in Korean Petrochemical Companies (재고관리성과가 에너지효율성에 미치는 영향에 대한 실증분석 : 국내 석유화학 기업을 대상으로)

  • Kim, Gilwhan;Lee, Jiwoong
    • Korean Management Science Review
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    • v.34 no.3
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    • pp.1-14
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    • 2017
  • This study empirically analyzes the impact of inventory management performance on the energy efficiency in Korean petrochemical companies. The concept of the distance function is used to define the energy efficiency and the estimation of the distance function is performed using the stochastic frontier analysis. The inventory turnover is selected as the variable indicating the inventory management performance of the company. The main results of this study are as follows. First, the inventory turnover has a positive impact on energy efficiency. Second, during the period over 2011~2015, while the gap in energy efficiency among the companies expanded, the average energy efficiency decreased. Third, the average energy efficiency in upstream process companies was greater than downstream process companies and the gap in energy efficiency among downstream process companies was greater than upstream process companies. Fourth, the average marginal effect of inventory turnover on energy efficiency increased gradually from 2011 to 2015. Finally, the average marginal effect of inventory turnover in downstream process companies was greater than upstream process companies, and the gap in the marginal effect of inventory turnover among downstream process companies was greater than upstream process companies. These results together imply the importance of inventory management in terms of energy efficiency.

Distance Weighted Filter based on Standard Deviation Distribution for AWGN Removal (AWGN 제거를 위한 표준편차 기반의 거리가중치 필터)

  • Park, Hwa-Jung;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2021.10a
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    • pp.118-120
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    • 2021
  • In modern society, with the development of IoT technology, various digital equipment is being distributed in a wide range of fields such as CCTV and exploration robots. Accordingly, the importance of data processing is increasing, and various studies are being conducted to remove noise generated in the process of receiving data in the imaging field. Representative noise includes additive white Gaussian noise (AWGN), and existing filters for removing noise include an average filter (AF), an alpha trimmed average filter (A-TAF), and a median filter (MF). However, existing filters have a disadvantage in that they show somewhat insufficient performance in noise removal characteristics in high frequency areas. Therefore, in this paper, in order to effectively remove AWGN existing in the high frequency region, a weight filter according to a distance based on the standard deviation is proposed.

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Heat Transfer from Single and Arrays of Impinging Water Jets(I)-Single Water Jet- (단일수분류 및 수분류군에 의한 열전달(I)-단일수분류-)

  • Eom, Gi-Chan;Lee, Jong-Su;Yu, Ji-O
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.21 no.9
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    • pp.1105-1114
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    • 1997
  • The heat transfer characteristics of free surface water jet impinging normally against a flat uniform heat flux surface were investigated. This deals with the effect of three nozzle configurations (Cone type, Reverse cone type, Vertical circular type) on the local and the average heat transfer. Heat transfer measurements were made for water jet issuing from a nozzle of which exit diameter 8 mm. The experimental conditions investigated are Reynolds number range of 27000 ~ 70000( $V_{O}$=3 ~ 8 m/s), nozzle-to-target plate distances H/D=2 ~ 10, and radial distance from the stagnation point r/D ~ = 0 ~ 7.42. For all jet velocities of H/D=2, the local Nusselt number decreased monotonically with increasing radial distance. However, for H/D from 4 to 10, and for the jet velocity $V_{O}$.geq.7 m/s for Cone type nozzle and $V_{O}$.geq.6 m/s for the other type nozzles, the Nusselt number distributions exhibited secondary peaks at r/D=3 ~ 3.5. For Reverse cone type nozzle and Vertical circular nozzle, the maximum stagnation point heat transfer and the maximum average heat transfer occurs at H/D=8. But for the Cone type nozzle, the maximum stagnation and average heat transfer occurs at H/D=10, 4, respectively. From the optimum nozzle-to-target plate distance, the stagnation and the average heat transfer reveal the following ranking: Reverse cone type nozzle, Vertical circular type nozzle, Cone type nozzle.ozzle.

Moving Object Extraction and Distance Measurement in Stereo Vision System (스테레오 비젼 시스템에서의 이동객체 추출 및 거리 측정)

  • 김수인;남궁재찬
    • Journal of Korea Multimedia Society
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    • v.5 no.3
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    • pp.272-280
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    • 2002
  • In this paper, we present a method to extract a moving object and to measure the distance to it by using the stereo vision system. The moving factor is to be extracted through a match of a pixel unit for the moving object where the adaptive threshold is effectively dealt with to remove changes in the brightness of the image. The distance to moving object is measured by using a stereo vision system which employs a parallel camera. The experimental results show that the proposed algorithm could be effectively applied to distance measurement to moving object because it has an average error of one percent.

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A Distance Estimation Method of Object′s Motion by Tracking Field Features and A Quantitative Evaluation of The Estimation Accuracy (배경의 특징 추적을 이용한 물체의 이동 거리 추정 및 정확도 평가)

  • 이종현;남시욱;이재철;김재희
    • Proceedings of the IEEK Conference
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    • 1999.11a
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    • pp.621-624
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    • 1999
  • This paper describes a distance estimation method of object's motion in soccer image sequence by tracking field features. And we quantitatively evaluate the estimation accuracy We suppose that the input image sequence is taken with a camera on static axis and includes only zooming and panning transformation between frames. Adaptive template matching is adopted for non-rigid object tracking. For background compensation, feature templates selected from reference frame image are matched in following frames and the matched feature point pairs are used in computing Affine motion parameters. A perspective displacement field model is used for estimating the real distance between two position on Input Image. To quantitatively evaluate the accuracy of the estimation, we synthesized a 3 dimensional virtual stadium with graphic tools and experimented on the synthesized 2 dimensional image sequences. The experiment shows that the average of the error between the actual moving distance and the estimated distance is 1.84%.

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Effect of Roadside Soil and Vegetation with Lead and Zine by Motor Vehicles (자동차 매연중의 미량금속이 토양 및 식물체에 미치는 영향)

  • 강상준
    • Journal of Plant Biology
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    • v.15 no.3
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    • pp.9-13
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    • 1972
  • This report deals with lead and zinc contamination of roadside soil and plants caused by motor vehicles as a function of distance from the road edge. The concentrations of Pb and Zn in roadside soil and plant samples from several locations decrease regularly with increasing distance from traffic. Soil samples up to 24m distance from the road edge are contaminated with more than 12.99ppm lead, and 13.40ppm zinc. The decrease in Pb and Zn contamination with increasing distance from the road is characteristically curvilinear; the relative coefficiency of Pb and Zn with distance is -0.69, -0.48, respectively. The average contents of Pb and Zn in plants are 21.5ppm and 30.00ppm. It is suggested that the contamination is related to the composition of gasoline, motor oil and to roadside of the residues of this metals.

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Extraction of Distance Information with Nonlinear Correlation of Photon-Counting Integral Imaging

  • Yeom, Seokwon
    • Journal of the Optical Society of Korea
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    • v.20 no.5
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    • pp.579-585
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    • 2016
  • Integral imaging combined with photon-counting detection has been researched for three-dimensional information sensing under low-light-level conditions. This paper addresses the extraction of distance information with photon-counting integral imaging. The longitudinal distance to the object is obtained utilizing photon-counting elemental images. The pixel disparity is estimated by maximizing the nonlinear correlation of photocounts. The first- and second-order statistical properties of the nonlinear correlation are theoretically derived. In the experiments, these properties are verified by varying the mean number of photocounts in the scene. The average distance is compared to that from the intensity information, showing the robustness of the proposed system even at low photocounts.

Analysis of the Travel Distance and the Number of Storage Location for Storage Location Allocation Methods in a Warehouse System (창고시스템에서 보관위치할당 방식에 대한 이동거리와 보관위치 수의 분석)

  • Chang, Suk-Hwa
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.29 no.2
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    • pp.58-66
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    • 2006
  • This paper addresses the analysis of the travel distance and the number of storage location for storage location allocation methods in a warehouse system. The dedicated, randomized, combined and limited storage methods are considered. The combined and the limited storage methods are suggested here, which the combined storage method is to divide the storage locations into the dedicated storage area and the randomized storage area, and the limited storage method is to restrict the storage area of each product. Through a numerical example, the average travel distance between input/output point and the storage locations, and the number of storage location needed in the warehouse are compared between storage location allocation methods. The nearest randomized storage method is shown as the reasonable one in the travel distance and the number of storage location.

A Study of the juveniles' Psychological Distance to Their Parents and Related Variables (청소년들의 부모에 대한 심리적 거리 및 관련 변인에 관한 연구 - 부산 지방을 중심으로 -)

  • 노영남
    • Journal of the Korean Home Economics Association
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    • v.20 no.4
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    • pp.205-223
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    • 1982
  • This study was devised to investigate the juveniles' psychological distance to their parents and related variables. 456 respondents, consisted of 116 middle school boys, 101 high school boys, 114 middle school girls and 125 high school girls, were sampled. The psychological distance was measured by the semantic differential method, and the statistical data were verified by the analysis of variance through computer system. The main results are found as follows. 1. The average mark of the juveniles' psychological distance to their parents was 54.73(78.19%)/70(100%) and the mark of high school girls was highest and high school boys lowest. 2. The variables influencing on the juveniles' psychological distance to their parents were varied buy the groups. 1) Middle school boys; home atmosphere(p<.001), social and economical status of home (S.E.S; p<.01), number of intimate friends(p<.05), rearing attitudes of parents(p<.05). 2) High school boys; home atmosphere(p<.001), age of father(p<.05), protection of mother(p<.05) 3) Middle school girls; home atmosphere(p<.001), rearing attitudes of parents (p<.001), S.E.S of home(p<.001).

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