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가시광통신 기반 광역 실내 초미세먼지 모니터링 시스템 (Visible Light Communication Based Wide Range Indoor Fine Particulate Matter Monitoring System)

  • 세잔 모하마드 아브라르 샤킬;안진영;한대현;정완영
    • 융합신호처리학회논문지
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    • 제20권1호
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    • pp.16-23
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    • 2019
  • PM 2.5로 불리는 초미세먼지는 인간의 건강을 해치는 2.5 ㎛ 이하 직경의 입자크기를 갖는 공기 중의 미세먼지를 말하며, 미세먼지 집중도는 공기 질 정보로 사용할 수 있다. 사람은 일반적으로 90% 이상을 실내에서 거주하며 실내에 대한 공식적인 먼지 집중도 자료는 제공되지 않기 때문에, 본 연구는 실내의 관점에서 공기 질 측정에 초점을 두었다. 실내 먼지데이터 모니터링은 병원과 같은 환경에서 매우 중요할 뿐만 아니라 교실, 시멘트 공장, 컴퓨터 서버 룸, 석유화학 저장고 등의 장소에서도 유용하게 사용할 수 있다. 본 논문에서는 전자기파로부터 자유로운 실내 먼지 모니터링을 위해 맨체스터 코딩기법을 이용한 가시광 통신 시스템을 제안한다. 넓은 범위의 먼지 집중도를 포함한 중요한 실내 환경정보가 가시광 채널을 통해 전송된다. 강력한 주변광 및 저주파 잡음 제거를 위해 평균전압트레킹 기법을 사용한다. 입력광은 광다이오드에 의해 수신되고, 동시에 수신 마이크로콘트롤러에 의해 신호처리 한다. 사용자는 실시간으로 실내 공기 질 정보를 모니터링 할 수 있으며, 공기 질 정보에 따라 미리 적합한 대처를 할 수 있다.

지불계수를 이용한 시험포장구간의 품질평가와 피로수명 분석 (An Evaluation on Quality of Field Trial Protocol using Pay Factor and Analysis of Fatigue Life)

  • 이재학;이석근;김성민;황상민
    • 한국도로학회논문집
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    • 제11권4호
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    • pp.133-142
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    • 2009
  • 본 연구는 지불계수를 이용하여 시험포장 구간의 품질을 평가하고 이에 따른 피로수명의 변화를 분석하기 위해 실시되었다. 특히 품질관리가 어려운 아스팔트 함량을 지불규정 기준인자로 선정하여 지불계수를 산출하였다. 먼저 아스팔트 함량이 피로수명에 미치는 영향을 확인하기 위하여 아스팔트 함량에 따른 피로수명의 연관성을 분석하였다. 이후 총 2회에 걸쳐 시험포장 구간에서 시료를 채취해서 지불계수를 산출하여 시험포장 구간의 품질을 평가하였으며, 지불계수에 따라 시험포장 구간의 품질에 차이가 있음을 확인 할 수 있었다. 시험포장 구간에 포설된 아스팔트 혼합물을 이용하여 시편을 제작, 피로수명을 분석하였다. 그 결과 지불계수가 높은 시험포장의 피로수명이 월등히 높음을 확인할 수 있었다. 이는 통계이론을 이용한 지불계수가 실제 포장의 피로수명을 반영한다는 것을 의미한다고 사료된다. 또한 시험포장 구간에 아스팔트 혼합물을 납품한 플랜트의 배합보고서와 동일한 시편을 제작하여 휨 피로시험을 실시하여 1, 2회차 시험포장의 피로수명들과 비교하였다. 그 결과 배합보고서를 기초로 제작한 시편의 피로수명이 시험포장 구간의 피로수명에 비해 월등히 높음을 알 수 있었다. 이는 입도나 기타 요인에 따른 공용성 감소현상이 발생 할 수 있음을 나타내는 것이라 사료된다. 따라서 지불규정을 적용중인 미국과 같이 입도, 공극률 등을 지불규정 기준인자로 선정하여 최종적인 지불계수를 산출하는 것이 보다 정확한 도로포장의 품질을 평가할 수 있을 것이다.

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Graduate perception of cosmetic surgery training in plastic surgery residency and fellowship programs

  • Ngaage, Ledibabari Mildred;Kim, Cecelia J;Harris, Chelsea;McNichols, Colton HL;Ihenatu, Chinezimuzo;Rosen, Carly;Elegbede, Adekunle;Gebran, Selim;Liang, Fan;Rada, Erin M;Nam, Arthur;Slezak, Sheri;Lifchez, Scott D;Rasko, Yvonne M
    • Archives of Plastic Surgery
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    • 제47권1호
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    • pp.70-77
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    • 2020
  • Background As the demand for cosmetic surgery continues to rise, plastic surgery programs and the training core curriculum have evolved to reflect these changes. This study aims to evaluate the perceived quality of current cosmetic surgery training in terms of case exposure and educational methods. Methods A 16-question survey was sent to graduates who completed their training at a U.S. plastic surgery training program in 2017. The survey assessed graduates' exposure to cosmetic surgery, teaching modalities employed and their overall perceived competence. Case complexity was characterized by the minimum number of cases needed by the graduate to feel confident in performing the procedure. Results There was a 25% response rate. The majority of respondents were residents (83%, n=92) and the remaining were fellows (17%, n=18). Almost three quarters of respondents were satisfied with their cosmetic training. Respondents rated virtual training as the most effective learning modality and observing attendings' patients/cases as least effective. Perceived competence was more closely aligned with core curriculum status than case complexity, i.e. graduates feel more prepared for core cosmetic procedures despite being more technically difficult than non-core procedures. Conclusions Despite the variability in cosmetic exposure during training, most plastic surgery graduates are satisfied with their aesthetic training. Incorporation of teaching modalities, such as virtual training, can increase case exposure and allow trainees more autonomy. The recommended core curriculum is adequately training plastic surgery graduates for common procedures and more specialized procedures should be consigned to aesthetic fellowship training.

재고전략 및 네트워크 구성에 따른 배송차량의 운영특성 연구 (Impacts of Delivery Vehicle Routing on Different Inventory Strategies and Network Configurations)

  • 원민수;강경우
    • 대한교통학회지
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    • 제28권5호
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    • pp.91-106
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    • 2010
  • 최근 유류비와 도로혼잡의 증가, 환경오염에 대한 높은 관심으로 인하여 공급체인에서 수송부분에 대한 다양한 이슈가 제시되고 있다. 특히, 공급자와 소매상에 유리한 전략들이 운송회사 입장에서도 반드시 유리하지 않다는 이슈가 제시되면서 다양한 연구가 시도되기 시작하였다. 그러므로 본 연구에서는 전통적인 공급체인분석 관점에서 벗어나 운송회사 입장에서 재고전략 및 네트워크 구성에 따른 공급체인의 운영특성을 파악하고, 그에 따른 운송회사의 운영환경을 해석하고자 한다. 분석방법은 가상의 공급체인을 구성하고, 각 네트워크(분산형, 집중형)구성에서 EOQ재고전략(Economic Order Quantity)과 POQ재고전략(Periodic Order Quantity)에 따른 배송차량의 운영특성(배송차량의 적재율, 소요대수, 운행시간 등)을 TranCAD프로그램을 이용하여 분석하였다. 분석결과, 재고전략이 EOQ 재고전략에서 POQ 재고전략으로 바뀌면 운송회사가 보유해야 하는 배송차량과 운전자의 수를 줄일 수 있었으며, 차량 운행시간이 감소하였다. 또한 네트워크 구성이 분산형에서 집중형으로 변경되면 차량 적재율이 향상되고 차량 운행시간이 감소하였다. 즉, 운송회사 입장에서는 분산형 네트워크에서 EOQ 재고전략을 이용하는 것보다는 집중형 네트워크를 구성하고 POQ 재고전략을 이용하는 것이 유리하다는 사실을 확인 할 수 있었으며, 이러한 효과는 월 1,300만원의 고정비와 월 260만원의 변동비 절감효과를 가져왔다.

Characterization of SiC nanowire synthesize by Thermal CVD

  • 정민욱;김민국;송우석;정대성;최원철;박종윤
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2009년도 제38회 동계학술대회 초록집
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    • pp.74-74
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    • 2010
  • One-dimensional nanosturctures such as nanowires and nanotube have been mainly proposed as important components of nano-electronic devices and are expected to play an integral part in design and construction of these devices. Silicon carbide(SiC) is one of a promising wide bandgap semiconductor that exhibits extraordinary properties, such as higher thermal conductivity, mechanical and chemical stability than silicon. Therefore, the synthesis of SiC-based nanowires(NWs) open a possibility for developing a potential application in nano-electronic devices which have to work under harsh environment. In this study, one-dimensional nanowires(NWs) of cubic phase silicon carbide($\beta$-SiC) were efficiently produced by thermal chemical vapor deposition(T-CVD) synthesis of mixtures containing Si powders and hydrocarbon in a alumina boat about $T\;=\;1400^{\circ}C$ SEM images are shown that the temperature below $1300^{\circ}C$ is not enough to synthesis the SiC NWs due to insufficient thermal energy for melting of Si Powder and decomposition of methane gas. However, the SiC NWs are produced over $1300^{\circ}C$ and the most efficient temperature for growth of SiC NWs is about $1400^{\circ}C$ with an average diameter range between 50 ~ 150 nm. Raman spectra revealed the crystal form of the synthesized SiC NWs is a cubic phase. Two distinct peaks at 795 and $970\;cm^{-1}$ over $1400^{\circ}C$ represent the TO and LO mode of the bulk $\beta$-SiC, respectively. In XRD spectra, this result was also verified with the strongest (111) peaks at $2{\theta}=35.7^{\circ}$, which is very close to (111) plane peak position of 3C-SiC over $1400 ^{\circ}C$ TEM images are represented to two typical $\beta$-SiC NWs structures. One is shown the defect-free $\beta$-SiC nanowire with a (111) interplane distance with 0.25 nm, and the other is the stacking-faulted $\beta$-SiC nanowire. Two SiC nanowires are covered with $SiO_2$ layer with a thickness of less 2 nm. Moreover, by changing the flow rate of methane gas, the 300 sccm is the optimal condition for synthesis of a large amount of $\beta$-SiC NWs.

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해바라기(Helianthus annuus L.) 근분비물질(根分泌物質)의 타감작용(他感作用) 및 타감물질(他感物質)의 동정(同定) II. 타감성(他感性) 해바라기 근분비물질(根分泌物質)의 동정(同定) (Allelopathic Activity and Determination of Allelochemicals from Sunflower (Helianthus annuus L.) Root Exudates II. Elucidation of Allelochemicals from Sunflower Root Exudates)

  • 박광호;;김순철;김길웅
    • 한국잡초학회지
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    • 제12권2호
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    • pp.173-182
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    • 1992
  • 해바라기의 상대억제작용(相對抑制作用)(타감작용(他感作用), Allelopathy) 및 천연제초제(天然除草劑)로서의 개발가능성(開發可能性)에 관한 시험(試驗)을 1988-1991년(年)에 걸쳐 국제미작연구소(國際米作硏究所) 농학(農學), 생화학부(生化學部) 및 국립(國立)필리핀 대학교(大學校) 화학과(化學科) 천연물(天然物) 연구실(硏究室)에서 수행(遂行)하여 얻은 결과중(結果中) 상대억제작용성(相對抑制作用性) 해바라기 근분비물질(根分泌物質)의 생물검정(生物檢定) 및 상대억제작용물질(相對抑制作用物質)(Allelochemicals)의 HPLC 분석결과(分析結果)는 다음과 같다. 1. 해바라기 근분비물질(根分泌物質)의 산(酸) 및 중성분획물질(中性分劃物質)을 생물검정재료(生物檢定材料)로 사용한 피 (Echinochloa colona (L.) Link 및 무 (Raphanus sativus L.)의 발아(發芽)가 유의성(有意性)있는 억제(抑制)를 보인 반면 알칼리 및 수용성분획(水溶性分劃)에서는 억제작용(抑制作用)이 나타나지 않았다. 2. 피의 경우 해 바라기 근분비물질(根分泌物質)의 분획물질(分劃物質) $10{\mu}l$ 농도(濃度)에서부터 유의적(有意的)인 생장억제(生長抑制)가 인정(認定)되었으며 지상부(地上部) 신장억제(伸張抑制)보다 지하부(地下部) 신장억제(伸張抑制)가 산(酸) 및 중성분획(中性分劃)에서 더 강하게 나타났다. 3 무의 경우 농도(濃度)에 관계없이 지상(地上) 및 지하부(地下部) 신장억제(伸張抑制)가 산(酸) 및 중성분획(中性分劃)에서 각각 높게 나타났다. 4. 생물검정(生物檢定)에서 강한 상대억제작용(相對抑制作用)을 보인 산성분획물질(酸性分劃物質)의 HPLC분석결과(分析結果) hydroquinone, ${\beta}$-resorcyclic acid, vanillic acid, caffeic acid, salicylic acid, quercetin 등의 물질(物質)이 확인(確認)되었다. 한편, 중성분획물질(中性分劃物質)에서는 Hydroquinone, gentisic acid, ${\beta}$-resorcyclic acid, vanillic acid, caffeic acid, ferulic acid, quercetin 등이 각각 동정(同定)되었다.

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보건의료정보의 법적 보호와 열람.교부 (A Study on Legal Protection, Inspection and Delivery of the Copies of Health & Medical Data)

  • 정용엽
    • 의료법학
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    • 제13권1호
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    • pp.359-395
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    • 2012
  • In a broad term, health and medical data means all patient information that has been generated or circulated in government health and medical policies, such as medical research and public health, and all sorts of health and medical fields as well as patients' personal data, referred as medical data (filled out as medical record forms) by medical institutions. The kinds of health and medical data in medical records are prescribed by Articles on required medical data and the terms of recordkeeping in the Enforcement Decree of the Medical Service Act. As EMR, OCS, LIS, telemedicine and u-health emerges, sharing and protecting digital health and medical data is at issue in these days. At medical institutions, health and medical data, such as medical records, is classified as "sensitive information" and thus is protected strictly. However, due to the circulative property of information, health and medical data can be public as well as being private. The legal grounds of health and medical data as such are based on the right to informational self-determination, which is one of the fundamental rights derived from the Constitution. In there, patients' rights to refuse the collection of information, to control recordkeeping (to demand access, correction or deletion) and to control using and sharing of information are rooted. In any processing of health and medical data, such as generating, recording, storing, using or disposing, privacy can be violated in many ways, including the leakage, forgery, falsification or abuse of information. That is why laws, such as the Medical Service Act and the Personal Data Protection Law, and the Guideline for Protection of Personal Data at Medical Institutions (by the Ministry of Health and Welfare) provide for technical, physical, administrative and legal safeguards on those who handle personal data (health and medical information-processing personnel and medical institutions). The Personal Data Protection Law provides for the collection, use and sharing of personal data, and the regulation thereon, the disposal of information, the means of receiving consent, and the regulation of processing of personal data. On the contrary, health and medical data can be inspected or delivered of the copies, based on the principle of restriction on fundamental rights prescribed by the Constitution. For instance, Article 21(Access to Record) of the Medical Service Act, and the Personal Data Protection Law prescribe self-disclosure, the release of information by family members or by laws, the exchange of medical data due to patient transfer, the secondary use of medical data, such as medical research, and the release of information and the release of information required by the Personal Data Protection Law.

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가미지황환이 저산소성 신경세포 손상에 미치는 영향 (Influence of Kamijihwang-hwan on the Hypoxic Damage of Cultured Cerebral Neurons from mouse and SK-N-MC cells)

  • 백은경;주성민;김근중;김대근;강정호;이영찬;이준;김영목;전병훈
    • 동의생리병리학회지
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    • 제17권4호
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    • pp.1082-1091
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    • 2003
  • To elucidate the neuroprotective effect of Kamijihwang-hwan(KSH) on nerve cells damaged by hypoxia, the cytotoxic effects of exposure to hypoxia were determined by XTT, NR, MTT and SRB asssay. The activity of catalase and SOD was measured by spectrophometry, and TNF-α and PKC activity was measured after exposure to hypoxia and treatment of Kamijihwang-hwan(KSH) water extract(KJHWE). Also the neuroprotective effect of KJHWE was researched for the elucidation of neuroprotective mechanism. The results were as follows ; Hypoxia decreased cell viability measured by XTT, NR assay when cultured cerebral neurons were exposed to 95% N2/5% CO₂ for 2~26 minutes in these cultures and KJHWE inhibited the decrease of cell viability. H₂O₂ treatment decreased cell viability measured by MTT, and SRB assay when cultured cerebral neurons were exposed to 1-80 uM for 6 hours, but KJHWE inhibited the decrease of cell viability. Hypoxia decreased catalase and SOD activity, and also TNF-α and PKC activity in these cultured cerebral neurons, but KJHWE inhibited the decrease of the catalase and SOD activity in these cultures. Hypoxia triggered the apoptosis via caspase activation and internucleosomal DNA fragmentation. Also hypoxia stimulate the release of cytochrome c form mitochondria. KJHWE inhibited the apoptosis via caspase activation induced by hypoxia. From these results, it can be suggested that brain ischemia model induced hypoxia showed neurotoxity on cultured mouse cerebral neurons, and the KJHWE has the neuroprotective effect in blocking the neurotoxity induced by hypoxia in cultured mouse cerebral neurons.

용접공진폐증 집단검진을 위한 단순 흉부방사선 촬영과 고해상 흉부전산화 단층촬영의 진단적 의의 (Diagnostic Meaning of High Resolution Computed Tomography Compared with Chest Radiography for Screening of Welder's lung)

  • 강정학;전진호;구혜원;고광수;유병철;손혜숙;이종태;이채언;김건일;최석진
    • Journal of Preventive Medicine and Public Health
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    • 제29권4호
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    • pp.853-861
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    • 1996
  • Pneumoconiosis is one of the major problem in the field of occupational health at Korea. Therefore, the efficient diagnosis of pneumoconiosis is a hot issue on the occupational health program. The author executed this study to estimate the diagnostic value of high resolution computed tomography(HRCT) compared with chest radiography for screening of welder's lung. HRCT was introduced very recently for the diagnosis of pneumoconiosis, however, the diagnostic value for screening of welder's lung - principally nonfibrogenic and reversible - has not been evaluated. The subjects were fifty cases of welder's lung or suspected cases who had been collected between 1989 and 1994 from one shipyard and continuously followed-up on the basis of in-plant periodic health check program. We applied both chest radiography and HRCT on the same subjects from May 1 to 30, 1996. The images were evaluated by two careered radiologists independently. The findings of chest radiography were classified into four category by ILO classification, and the findings of HRCT according to the criteria of Bergin et al. The concordance between two radiologists expressed with Kendall's tau-b was 0.72 by chest radiography and 0.44 by HRCT- that is, interobserver variation of HRCT was bigger than that of chest radiography. The concordance between the two different methods was highly variable as 0.44 by radiologist A and 0.06 by radiologist B - that is, interobserver variation was very big. However, HRCT looked more detectable for the minor parenchymal change. These findings suggested that it is not appropriate to use HRCT routinely for screening of welder's lung due to lack of diagnostic criteria, and feasibility, acceptability and economic aspects. Nevertheless, HRCT might be recommendable in the case of equivocal parenchymal features on the chest radiography, unexplained respiratory symptoms, and/or lung function abnormalities suggestive of interstitial fibrosis.

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종합대학 도서관장서의 적정량기준 설정에 관한 고찰 -미국의 종합대학도서관기준을 중심으로- (Problems in Quantification of Adequacy of Academic Library Collections -Critical Analysis of Standards for Academic Libraries in the U.S.-)

  • 정용선
    • 한국문헌정보학회지
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    • 제8권
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    • pp.183-207
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    • 1981
  • Library standards have been the source of considerable controversy, whereas many problems are involved in developing stardard for university library collections. For evaluation purposes, standards should be precise, quantifiable and measurable. In the United States, however, standards for academic libraries are limited to qualitative statements and principles. Quantitative standards, when given, are ususally related to the number of population in the institution being served, or the prescribed quantitative objectives are often arbitrarily formulated by value judgements. The study in this paper attempts to explain the problems involved in developing quantitative standard for academic library collections. Two problems facing in the formulation of the optimal size of collection are identified. One is the theoretically faulty concept of adequacy of collection to meet the situations of diversity of university libraies, and the other is the difficulties in quantification and measurement, along with the lack of concept of adequacy of collection. However, quantification of adequate size of collection is proved to be useful on the pratical level, even though not valid theoretically. ACRL, Clapp/Jordan and Voigt developed formulas or models for setting the optimal size of a library collection for any particular university library. The main purpose of this study is the analysis of the above formulas. ACRL standard was drawn from obervation and analysis of statistcs in leading library collections. In academic field, this judgement appears to have been based on the assumption that a high-grade institution would be apt to have a good library collection. This study criticizes ACRL standard for its failure to include some determinants of measurements, and points out the limitations of the standard. In contrast. Clapp/Jordan developed a formula rather scientifically based upon bibliographical sources. This is similarly empirical but has the advantage of bringing into play the elements which make universities diverse in nature. Both ACRL and Clapp/Jordan formulas share two major defects. (1) the specific subject needs of the collection are not indiacted directly, and (2) percentage rate of growth is an indicator in measuring the potential utility of a collection. Thus both formulas failed to provide a basis for meaningful evaluation. Voigt further developed a model for determining acquisition rates for currently published materials based on bibliographic technique. Voigt model encourages experimentation with different programs and different allocations of input resources, designed to meet the needs of the library's particular population. Standard for university library collections can be formulated in terms of input(traditional indicator), or additionally, in terms of output(cost-effectiveness). Cost effectiveness is expressed as user satisfaction, ability to provide wanted materials within a reasonable time period. Thus simple quantitative method does not cover all the situations of diversity of university library collections, nor measures the effectiveness of collections. Valid standard could not be established without further research.

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