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A Study for Improving Destruction Appraisal System of Records: Focusing on the Destruction Appraisal Case of A City Record Center (기록물 폐기평가 제도 개선방안에 관한 연구 - A시청 기록관 폐기평가 사례를 중심으로 -)

  • Kim, Myoung-Hun
    • Journal of Korean Society of Archives and Records Management
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    • v.15 no.4
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    • pp.7-24
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    • 2015
  • Destruction appraisal system improved with the enactment of the 1999 Public Records Management Act has the strategic concepts to prevent loss of important records with prohibiting the destruction in creation organization of records. But destruction appraisal carried out in record center realistically has the big difference with destruction appraisal system intended by Public Records Management Act. Therefore this article intends to explore the importance of destruction appraisal system through a review of the record appraisal system, and investigates operation status of destruction appraisal system in record center and operational issues. And it intends to explore scheme for practical application of destruction appraisal system based on actual cases of destruction appraisal which operates as a model.

Estimation of Probable Precipitation considering Altitude in the Jeju Islands (제주도의 고도를 고려한 확률강우량 산정)

  • Ko, Jae-Wook;Yang, Sung-Kee;Jung, Woo-Yul;Yang, Se-Chang
    • Journal of Environmental Science International
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    • v.23 no.4
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    • pp.595-603
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    • 2014
  • Jeju Island, a volcanic island, is the region that shows the biggest rainfall and has a big elevation-specific deviation of precipitation, but Jeju Island River Maintenance Plan doesn't reflect the characteristics of Jeju Island as it only calculates probable precipitation from four weather stations with elevation less than 100m. Therefore, this study uses AWS observational data in four Jeju Island weather stations and other regions to calculate location-specific probable precipitation, review the elevation-probable precipitation correlation in southern and northern regions, and create a probable precipitation map for all regions of Jeju Island, in order to produce better outcomes. This study is expected to be the most basic data to establish a safe Jeju island from flood disaster in preparation for the future climate changes and widely used for Jejudo Basin Dimension Planning, River Maintenance Plan, Pre-Disaster Impact Review, etc.

Adoption of Virtual Technology to the Development of a BIM based PMIS

  • Suh, Bong-Gyo;Lee, Ghang;Yun, Seok-Heon
    • Journal of the Korea Institute of Building Construction
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    • v.13 no.4
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    • pp.333-340
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    • 2013
  • As construction projects become bigger, PMIS is being used as a project collaboration tool for project participants, owners, designers, inspectors and contractors. As the data type used in PMIS is usually text and most PMIS have no standard information classification system, there is a problem with data usability, such as the capacity for data search and analysis. BIM uses Objects and Properties, and this information might be used for relating with other construction information. As such, BIM technologies can be used with PMIS to enhance the data usability. The web environment is very convenient for multiple users, but the problem is that the data transfer speed is low for big files such as BIM model files. In this study, we suggested a Virtual Technology (VT) application to enhance the performance of BIM data exchange in PMIS, and tested and analyzed its efficiency when it is used to integrate BIM and PMIS in the web environment. The results of the study showed that VT can be used to enhance the efficiency of BIM data exchange in the web environment.

A Study on the Concept of Schools and Spatial Composition According to Educational Philosophy by John Dewey (존 듀이의 교육철학에 따른 학교와 공간구성 개념 고찰)

  • Rieu, Ho-Seoup
    • Journal of the Korean Institute of Educational Facilities
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    • v.23 no.4
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    • pp.21-30
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    • 2016
  • This study considers the concept of schools and their spatial composition by John Dewey through literature review who argued for a new, children-centered education in the early 19th century, and it also mentions some suggestions for improvement of the elementary school facilities in Korea that the size and number of students in school has decreased sharply. John Dewey claimed that a school is a big household as well as a small society in which one studies the current occupation and experience in connection between the household-school-society. At the same time, he pursued an organic and open spatial composition which can effectively and efficiently enable educational curriculum's application, social occupation and project learning based on children's native impulse and stage in child growth. Korea's education policy should shift from quantity-based education production to quality-based production due to the reduction of school age population among other reasons. Especially this study emphasizes that small size schools need to be changed to local community facilities with environment-friendly, children-centered and open learning spatial composition with basis on John Dewey's educational philosophy.

Transmission Network Expansion Planning for the Penetration of Renewable Energy Sources - Determining an Optimal Installed Capacity of Renewable Energy Sources

  • Kim, Sung-Yul;Shin, Je-Seok;Kim, Jin-O
    • Journal of Electrical Engineering and Technology
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    • v.9 no.4
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    • pp.1163-1170
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    • 2014
  • Due to global environmental regulations and policies with rapid advancement of renewable energy technologies, the development type of renewable energy sources (RES) in power systems is expanding from small-scale distributed generation to large-scale grid-connected systems. In the near future, it is expected that RES achieves grid parity which means the equilibrium point where the power cost of RES is equal to the power costs of conventional generators. However, although RES would achieve the grid parity, the cost related with development of large-scale RES is still a big burden. Furthermore, it is hard to determine a suitable capacity of RES because of their output characteristics affected by locations and weather effects. Therefore, to determine an optimal capacity for RES becomes an important decision-making problem. This study proposes a method for determining an optimal installed capacity of RES from the business viewpoint of an independent power plant (IPP). In order to verify the proposed method, we have performed case studies on real power system in Incheon and Shiheung areas, South Korea.

Under Sampling for Imbalanced Data using Minor Class based SVM (MCSVM) in Semiconductor Process (MCSVM을 이용한 반도체 공정데이터의 과소 추출 기법)

  • Pak, Sae-Rom;Kim, Jun Seok;Park, Cheong-Sool;Park, Seung Hwan;Baek, Jun-Geol
    • Journal of Korean Institute of Industrial Engineers
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    • v.40 no.4
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    • pp.404-414
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    • 2014
  • Yield prediction is important to manage semiconductor quality. Many researches with machine learning algorithms such as SVM (support vector machine) are conducted to predict yield precisely. However, yield prediction using SVM is hard because extremely imbalanced and big data are generated by final test procedure in semiconductor manufacturing process. Using SVM algorithm with imbalanced data sometimes cause unnecessary support vectors from major class because of unselected support vectors from minor class. So, decision boundary at target class can be overwhelmed by effect of observations in major class. For this reason, we propose a under-sampling method with minor class based SVM (MCSVM) which overcomes the limitations of ordinary SVM algorithm. MCSVM constructs the model that fixes some of data from minor class as support vectors, and they can be good samples representing the nature of target class. Several experimental studies with using the data sets from UCI and real manufacturing process represent that our proposed method performs better than existing sampling methods.

Core Safety Disposition as a Cause of Safety Consciousness (안전 의식의 결정 요인으로서 핵심 안전 성향)

  • Park, Young Seok;Jung, Ji Hee
    • Journal of the Korean Society of Safety
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    • v.34 no.6
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    • pp.58-64
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    • 2019
  • Over the past decades there has been a growing body of researches that examines the psychological traits related to safety outcomes. After briefly reviewing the relationships between psychological dispositions and safety outcomes, we empirically examine the relationships with 2 samples of 1,102 participants. Fifteen psychological dispositions (big 5 personality, locus of control, cognitive failure, affection from job and relations, 4 achievement goal orientations, self-efficacy, fatigue, and depression) and four psychological outcomes (safe behavior, unsafe behavior, accidents, and injuries) are examined. After covariance structure modeling variances of safety outcomes are well explained by simple 4 dispositions of consciousness, mastery-approach goal orientation, self-efficacy, and depression. We name them 'core safety disposition', and name four psychological outcomes 'safety consciousness', and the relationships between those latent variables are stronger than between measurement variables. We propose core safety disposition as a cause of safety consciousness, and discuss implications for research and practices.

A Study on Droplet Distribution of Bio Diesel Fuels Using Immersion Sampling Method (액침법에 의한 바이오디젤유의 액적분포에 관한 연구)

  • Kim, M.S.;Doh, H.C.;Koh, D.K.;Ahn, S.K.
    • Journal of Power System Engineering
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    • v.10 no.4
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    • pp.5-10
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    • 2006
  • The purpose of this study is to measure the droplet distribution and Sauter mean diameter(SMD) of biodiesel fuel, using the immersion sampling method. This method involves using an optical microscope and a CCD camera, to take an image of the droplets. These images are then measured by using a 'Sigma Scan' processing program. The results of the above experiment are summarized as followed ; (1) There can be as much as a 10% error rate when measuring the diameter of these droplets, using the image processing method and the naked eye. (2) The result of droplet size distribution test, TVO(transesterified vegetable oil) big size droplet distribution were increased at ambient pressure $6kg/cm^2$. (3) When ambient pressure increased $6kg/cm^2$ above, SMD variation of TVO and UVO(used vegetable oil) 30 are small. (4) On Rosin-Rammler analysis, droplets size distribution of UVO(used vegetable oil) 30 uniform more than TVO 20 on ambient pressure $1kg/cm^2$.

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Analysis of Welding Positions for Reduction of Musculoskeletal Disorders Based on Simulation Technique (시뮬레이션 기법에 기초한 근골격계 질환 감소를 위한 용접자세 분석)

  • Park, Ju-Yong;Kim, Dong-Joon;Chang, Seong-Rok;Song, Chang-Sub
    • Journal of Welding and Joining
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    • v.25 no.4
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    • pp.79-85
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    • 2007
  • The industrial disaster caused by a work-related disease like a Musculoskeletal Disorders(MSDs) becomes a big social problem and increases rapidly. This leads to the degradation of the labor desire and the productivity. Welding work belongs to the work with a high intensity. This paper aims to analyze the welding work in the various positions from a view-point of the burden of the human musculoskeletal system and to propose the desired position with lower burden. For this purpose the real welding work was observed in the shipyard and analyzed using the RULA method, a powerful ergonomics tool. The 3-dimensional simulation model fur this work was also developed. In this model, ergonomics human model and welding work environment were built. This model was verified through the comparison to the real work. This paper showed that the improvement of welding position by changing the location of a stool and using some auxiliary tool can reduce the work intensity remarkably and lead to the decrease of MSDs.

Effects of Sputter Parameters on Electrochromic Properties of Tungsten Oxide Thin Films Grown by RF Sputtering

  • Nah, Yoon-Chae
    • Korean Journal of Materials Research
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    • v.21 no.12
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    • pp.703-707
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    • 2011
  • The electrochromic properties of tungsten oxide films grown by RF sputtering were investigated. Among the sputter parameters, first the $Ar:O_2$ ratios were controlled with division into only an $O_2$ environment, 1:1 and 4:1. The structure of each film prepared by these conditions was studied by X-ray diffraction, X-ray photoelectron spectroscopy and Rutherford backscattering spectroscopy. The sputter-deposited tungsten oxide films had an amorphous structure regardless of the $Ar:O_2$ ratios. The chemical compositions, however, were different from each other. The stoichiometric structure and low-density film was obtained at higher $O_2$ contents. Electrochemical tests were performed by cyclic voltammetry and chronoamperometry at 0.05 M $H_2SO_4$ solutions. The current density and charge ratio was estimated during the continuous potential and pulse potential cycling at -0.5 V and 1.8 V, respectively. The film grown in a higher oxygen environment had a higher current density and a reversible charge reaction during intercalation and deintercalation. The in-situ transmittance tests were performed by He-Ne laser (633 nm). At higher oxygen contents, a big transmittance difference was observed but the response speed was too slow. This was likely caused by higher film resistivity. Furthermore, the effect of sputtering pressure was also investigated. The structure and surface morphology of each film was observed by X-ray diffraction and scanning electron microscopy. A rough surface was observed at higher sputtering pressure, and this affected the higher transmittance difference and coloration efficiency.