• Title/Summary/Keyword: collection

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Designing Refuse Collection Networks under Capacity and Maximum Allowable Distance Constraints

  • Kim, Ji-Su;Lee, Dong-Ho
    • Management Science and Financial Engineering
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    • v.19 no.2
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    • pp.19-29
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    • 2013
  • Refuse collection network design, one of major decision problems in reverse logistics, is the problem of locating collection points and allocating refuses at demand points to the opened collection points. As an extension of the previous models, we consider capacity and maximum allowable distance constraints at each collection point. In particular, the maximum allowable distance constraint is additionally considered to avoid the impractical solutions in which collection points are located too closely. Also, the additional distance constraint represents the physical distance limit between collection and demand points. The objective is to minimize the sum of fixed costs to open collection points and variable costs to transport refuses from demand to collection points. After formulating the problem as an integer programming model, we suggest an optimal branch and bound algorithm that generates all feasible solutions by a simultaneous location and allocation method and curtails the dominated ones using the lower bounds developed using the relaxation technique. Also, due to the limited applications of the optimal algorithm, we suggest two heuristics. To test the performances of the algorithms, computational experiments were done on a number of test instances, and the results are reported.

A Study on the Development of the Founding Collection in Public Libraries (공공도서관 개관장서 구축 방안 연구)

  • Chang, D.H.
    • Journal of Korean Library and Information Science Society
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    • v.48 no.4
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    • pp.303-320
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    • 2017
  • This study illustrates the process of the development of founding collection in public libraries. Specifically, this study surveys such cases of ten public libraries recently opened. It also analyzes current laws and standards about library collection and compares the criteria with the ones in various manuals and reports. For the study, supplementary data were also collected through qualitative interviews and brain-storming discussions with public librarians and other regional government officials who were in charge of the library construction project. For the suggestion to improve the quality of such founding collection, the researcher put the emphasis on the construction of collection development policy for the library, on the official collection plan, on the adequate volume of founding collection, and on the strategies for collection programs about regional studies.

광폭 전기집진기의 집전특성에 관한 연구 - I. 집진판 간격과 방전극의 영향 -

  • 김용진;하병길;정상현;홍원석;여석준;유주식
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.13 no.10
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    • pp.939-946
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    • 2001
  • This study investigates the electrical and collection characteristics of a wide plate spacing electrostatic precipitator (ESP), using a pilot-scale one. Electrical operating characteristics and collection efficiency were measured for various shapes of discharge electrodes. The collection plate spacing ranged from 300 to 550 mm. Results of electrical characteristic and collection efficiency tests as a function of collection plate spacing, discharge electrode type, applied voltage, and particle diameter were obtained. Increasing the collection plate pitch and altering the corona electrode geometry was found to increase the collection efficiencies without increasing input power requirement. The best efficiency is achieved for the discharge electrode of twisted pin type.

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Development and Application of Rainwater Collection Model by the Ground (우수의 지표 포집 모델의 개발 및 적용)

  • Lee, Dong-Kon;Lee, Kil-Soo;Wang, Chang-Keun
    • Journal of Korean Society of Water and Wastewater
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    • v.19 no.2
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    • pp.173-180
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    • 2005
  • In this study, quantity and quality of collected rainwater by the ground collection system were investigated and the Rainwater Collection Prediction Model was developed to predict the amount of collected rainwater. The quantity of collected rainwater in the collection system was 9516 L(38.2%) and the quantity of infiltrated rainwater in the collection system was 9946 L(40.2%) through $25m^2$ area for the study period, respectively. Average turbidity of collected rainwater in collection system was 2.2 NTU, and average turbidity of infiltrated rainwater in collection system was 2.3 NTU for study period, respectively. The predicted amount by the model and the actual collected amount were 9842.4 L and 9516 L, which were very close showing that prediction was excellent. The optimal rainwater storage tank volume was simulated with a certain consumption condition for various cities with different rainfall patterns.

A Study on the Cloud Collection (클라우드 컬렉션에 관한 연구)

  • Cho, Jane
    • Journal of Korean Library and Information Science Society
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    • v.43 no.1
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    • pp.201-219
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    • 2012
  • Cloud collection, which is derived from cloud computing, is a framework that creates new value through library cooperative platform to preserve and manage libraries' duplicated collection. Due to E-book market vitalization and mass digitalization of retrospective print material, new library collection management paradigm has been expected that licensed based E-book service and management of shared print repository. This study discuss cloud collection concept which digital repository and Shared print repository are in complementary relations. And suggest cloud collection model can be applicable to Korean university libraries.

Agenda and Paradox of Collection Development in Public Libraries (공공도서관 장서개발의 정론과 역설)

  • Yoon, Hee-Yoon
    • Journal of Korean Library and Information Science Society
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    • v.40 no.1
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    • pp.5-22
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    • 2009
  • The social identities and role models of all public libraries originate from the historical and systematic development of analog collections and the high-quality digital contents. Therefore, collection development in public libraries should be treated the most important professional task. Based on these prerequisites, this paper analyzed the classical agendas of analog collection development and paradoxes of digital odyssey, and suggested the future policies and strategies of public library collection development in Korea.

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A Study on Development of a National Collection Management Guideline for the School Library (국가 수준의 학교도서관 장서관리지침서 개발에 대한 연구)

  • Lee, Seung-Gil;Song, Gi-Ho
    • Journal of the Korean Society for Library and Information Science
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    • v.51 no.3
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    • pp.23-44
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    • 2017
  • The purpose of this study is to develop detailed items and elements to be included in a national guideline for school library collection which can be used as a basis and standard for establishing collection management policies in individual school libraries. For this purpose, materials related to the collection management of school library were analyzed with the international and national level. As a result, the international materials emphasizes accessibility and resource sharing of digital materials besides quantitative standards of the library collection and deal with the process for the objection collection. In this study, items to be included in the national guidelines are divided into general principles of collection management and collection management guidelines, and elements of the each item are suggested. And proposed systematic bases for efficient application of the national guidelines to school libraries.

Evaluation of the Fiction Collection of Public Libraries Based on Use Factor (이용계수를 적용한 공공도서관 소설장서 평가)

  • Yoon, Hee-Yoon;Kim, Il-Young
    • Journal of Information Management
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    • v.42 no.4
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    • pp.175-194
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    • 2011
  • This study evaluated the fiction collection of Korean public libraries by applying use factor and suggested various measures to enhance collection development function. As a result, while the collection building and borrowing ratios of Korean literature in literature collection by language were the highest at 62.6% and 54.3% respectively, the use factor was lower than the base value(1.00). And while the collection building and borrowing ratios of Korean contemporary fiction by item category were the highest at 65.60% and 51.36% respectively, the use factor was lower than the base value and the use factor by year is decreasing in recent years. The reason is because of poor collection development. Therefore, public library need to consider active alternatives such as establishment of the collection development policy and fiction collection development guideline, composition of the fiction material selection committee, adaption of the dedicated librarian system for fiction material development, development and utilization of a selection tool for fiction materials, and periodic evaluation of fiction collection.

Improvement of an Identified Slot Sacn-Based Active RFID Tag Collection Algorithm (인식 슬롯 스캔 기반 능동형 RFID 태그 수집 알고리즘 개선)

  • Yoon, Won-Ju
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38B no.3
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    • pp.199-206
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    • 2013
  • This paper proposes a modified tag collection algorithm that improves the drawback of the identified slot scan-based tag collection algorithm presented in a previous paper to improve the tag collection performance in active RFID systems. The previous identified slot scan-based tag collection algorithm is optimized in situations where all the tags store the fixed size of data, so it could not result in a good performance improvement with tags having the variable size of data. The improved tag collection algorithm proposed in this paper first collects the slot size information required for the data transmission from each tag via the identified slot scan phase, and then performs the tag collection phase using the information, which resolves the problem of the previous identified slot scan-based tag collection algorithm. The simulation results for performance evaluation showed that the proposed tag collection algorithm resulted in the almost same tag collection performance as the previous algorithm when all the tags have the same size of data and led a large improvement of the tag collection performance in ISO/IEC 18000-7 unlike the previous algorithm when each tag has a random size of data.