• 제목/요약/키워드: open set

검색결과 1,093건 처리시간 0.029초

Geotechnical Engineering Progress with the Incheon Bridge Project

  • Cho, Sung-Min
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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    • pp.133-144
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    • 2009
  • Incheon Bridge, 18.4 km long sea-crossing bridge, will be opened to the traffic in October 2009 and this will be the new landmark of the gearing up north-east Asia as well as the largest & longest bridge of Korea. Incheon Bridge is the integrated set of several special featured bridges including a magnificent cable-stayed girder bridge which has a main span of 800 m width to cross the navigation channel in and out of the Port of Incheon. Incheon Bridge is making an epoch of long-span bridge designs thanks to the fully application of the AASHTO LRFD (load & resistance factor design) to both the superstructures and the substructures. A state-of-the-art of the geotechnologies which were applied to the Incheon Bridge construction project is introduced. The most Large-diameter drilled shafts were penetrated into the bedrock to support the colossal superstructures. The bearing capacity and deformational characteristics of the foundations were verified through the world's largest static pile load test. 8 full-scale pilot piles were tested in both offshore site and onshore area prior to the commencement of constructions. Compressible load beyond 30,000 tonf pressed a single 3 m diameter foundation pile by means of bi-directional loading method including the Osterberg cell techniques. Detailed site investigation to characterize the subsurface properties had been carried out. Geotextile tubes, tied sheet pile walls, and trestles were utilized to overcome the very large tidal difference between ebb and flow at the foreshore site. 44 circular-cell type dolphins surround the piers near the navigation channel to protect the bridge against the collision with aberrant vessels. Each dolphin structure consists of the flat sheet piled wall and infilled aggregates to absorb the collision impact. Geo-centrifugal tests were performed to evaluate the behavior of the dolphin in the seabed and to verify the numerical model for the design. Rip-rap embankments on the seabed are expected to prevent the scouring of the foundation. Prefabricated vertical drains, sand compaction piles, deep cement mixings, horizontal natural-fiber drains, and other subsidiary methods were used to improve the soft ground for the site of abutments, toll plazas, and access roads. Light-weight backfill using EPS blocks helps to reduce the earth pressure behind the abutment on the soft ground. Some kinds of reinforced earth like as MSE using geosynthetics were utilized for the ring wall of the abutment. Soil steel bridges made of corrugated steel plates and engineered backfills were constructed for the open-cut tunnel and the culvert. Diverse experiences of advanced designs and constructions from the Incheon Bridge project have been propagated by relevant engineers and it is strongly expected that significant achievements in geotechnical engineering through this project will contribute to the national development of the longspan bridge technologies remarkably.

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부산시 노거수의 공간구성에 관한 연구 -생육환경 및 배치형태를 중심으로- (A study on old trees as they relate to the organization of space in Pusan -Attaching importance to the growth environment and arrangement form in space-)

  • 김승환;김순희
    • 한국조경학회지
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    • 제24권2호
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    • pp.86-98
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    • 1996
  • This study is intended to revaluate old tree, five of the shot of the Natural Monument and 66 shot trees under protection in the city at present. The study covers distribution, management of usage, investigation and research into various matters relating to the situation of old trees in Pusan. Because 60% of the old trees selected for protection is on private land, citizens have difficulty gaining access to them. Also space for growth is impinged on by various urban facilities. Some trees have problems of growth because the land is covered with cement and asphalt. As regards space for old trees, many places have been destroyed due to the lack of protection fences and the failure to establish a guidance board. Only 40% of the space has been set aside for rest. In these places the establishment of rest areas, benches and handy chairs is needed. And there are 20 holy places where people observe religious ceremonies. As for space security necessary for old trees according to trunk width, the minimum trunk width and availale area needed are more than 1:1.5, but less than 30% have the necessary space. The growth of many old trees is threatended because of the small apace for growth. The prescription of the boundary space is divided between inside and outside. This indicates the domain nature and space rank of the old tree. It can be classified into five forms for research purposes. The elements for prescription of critical space outside are connected with the security of space, and the elements relating to inside space portray the conditions for sensitive growth according to the institution and the ground conditions. The open and closed nature of old tree space has some connection with the relationship between usage and the intimacy of the user. Most of the spaces for old trees can't be used or are difficult to gain access to, so it is necessary to secure enough space for them. The 18 places, despite having easy access, are near farmland, hills or forest. So the intimacy factor is low, and the security of space of the old trees is not generally sufficient. Henceforth, it will be necessary to have security of area for old trees as well as maintenance control to protect them. Also the space should be used as a communal and recreation are in the city. It is the time to construct a landscaped area which people can easily approach, a place with a secure entrance where they can play, rest and converse.

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한.중.일 다자간 어업협력체 구성방안 연구 (A Study on the Construction of the Multiple Fishery Cooperation System Between Korea, China and Japan)

  • 심호진
    • 수산경영론집
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    • 제39권2호
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    • pp.81-108
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    • 2008
  • Since the declaration made by UN Convention on the Law of the Sea on EEZs, The open seas of Northeast Asia, considerd as a convention area, needed new agreements in conformity with the changes brought by the introduction of the Exclusive Economic Zone(EEZ) system. The Contracting Parties of these agreements set up their own EEZs, which extend certain ranges from their baselines, Fishing in the other party's EEZ is done based on mutual agreements, which take into account traditional fishing activity in the zones. Seperate fishries management systems, in accordance with the relevant legal status of the waters, are applied to individual overlapping areas: Middle Zone in the Bast Sea and the waters south of jeju Island, Interim Measure Zone in the Yellow Sea and East China Sea, and the Transitional Zone in the Yellow Sea. They decided to conclude fisheries agreements as the provisional agreement under Article 74(3) of the UN Convention before the delimitations of the EEZs to avoid the territorial disputes. China and Japan concluded the Fishries Agreement in the November 1997, allowing each coastal State 52 mile EEZ. it was followed by Korea and Japan in September 1998, reaching a final compromise. And also Korea and China came to a satisfactary settlement in November 1998. Fisheries agreements have been established between the three North-east Asian States, the agreement are all bilateral. That implies inefficient resource management on the overlapping waters of the three states, especially on the East China Sea. The Korea-Japan Fisheries Agreement and the China-Japan Fishery Agreement worked as governing rules in the North-east Asian seas before the establishment of EEZs (Exclusive Economic Zones). However the conclusion of the bilateral fishery agreements, Korea China and Japan have developed EEZs, and these three countries have competed for the exploitation of fisheries resources. Therefore, the issue of fisheries resource management was no longer a single countries' problem and emerged as a common issue facing these three countries. In recognition of the above-mentioned problem, it is needed for the construction of cooperative System fishery management in the North-east Asian seas. Therefore, cooperative measures should be establishied. The final goal of the construction of fisheries management cooperative system is to establish sustainable fisheries in the North-east Asian seas. However, there is a big difference in fisheries management tools, fishing gear, exploitation rate of species, etc. This implies that a careful approach should be taken in order to achieve the cooperative fisheries management among Korea, China and Japan. conclusionly, the Governments of Korea, China and Japan should complement three bilateral agreemens, and which they prepares to 'Fisheries Resource Restore Program' Between Korea, China and Japan in the adjacent waters south of Jeju Island.

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딥 러닝 기반 코로나19 흉부 X선 판독 기법 (A COVID-19 Chest X-ray Reading Technique based on Deep Learning)

  • 안경희;엄성용
    • 문화기술의 융합
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    • 제6권4호
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    • pp.789-795
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    • 2020
  • 전 세계적으로 유행하는 코로나19로 인해 많은 사망자가 보고되고 있다. 코로나19의 추가 확산을 막기 위해서는 의심 환자에 대해 신속하고 정확한 영상판독을 한 후, 적절한 조치를 취해야 한다. 이를 위해 본 논문은 환자의 감염 여부를 의료진에게 제공해 영상판독을 보조할 수 있는 딥 러닝 기반 코로나19 흉부 X선 판독 기법을 소개한다. 우선 판독모델을 학습하기 위해서는 충분한 데이터셋이 확보되어야 하는데, 현재 제공하는 코로나19 오픈 데이터셋은 학습의 정확도를 보장하기에 그 영상 데이터 수가 충분하지 않다. 따라서 누적 적대적 생성 신경망(StackGAN++)을 사용해 인공지능 학습 성능을 저하하는 영상 데이터 수적 불균형 문제를 해결하였다. 다음으로 판독모델 개발을 위해 증강된 데이터셋을 사용하여 DenseNet 기반 분류모델 학습을 진행하였다. 해당 분류모델은 정상 흉부 X선과 코로나 19 흉부 X선 영상을 이진 분류하는 모델로, 실제 영상 데이터 일부를 테스트데이터로 사용하여 모델의 성능을 평가하였다. 마지막으로 설명 가능한 인공지능(eXplainable AI, XAI) 중 하나인 Grad-CAM을 사용해 입력 영상의 질환유무를 판단하는 근거를 제시하여 모델의 신뢰성을 확보하였다.

Converting Panax ginseng DNA and chemical fingerprints into two-dimensional barcode

  • Cai, Yong;Li, Peng;Li, Xi-Wen;Zhao, Jing;Chen, Hai;Yang, Qing;Hu, Hao
    • Journal of Ginseng Research
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    • 제41권3호
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    • pp.339-346
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    • 2017
  • Background: In this study, we investigated how to convert the Panax ginseng DNA sequence code and chemical fingerprints into a two-dimensional code. In order to improve the compression efficiency, GATC2Bytes and digital merger compression algorithms are proposed. Methods: HPLC chemical fingerprint data of 10 groups of P. ginseng from Northeast China and the internal transcribed spacer 2 (ITS2) sequence code as the DNA sequence code were ready for conversion. In order to convert such data into a two-dimensional code, the following six steps were performed: First, the chemical fingerprint characteristic data sets were obtained through the inflection filtering algorithm. Second, precompression processing of such data sets is undertaken. Third, precompression processing was undertaken with the P. ginseng DNA (ITS2) sequence codes. Fourth, the precompressed chemical fingerprint data and the DNA (ITS2) sequence code were combined in accordance with the set data format. Such combined data can be compressed by Zlib, an open source data compression algorithm. Finally, the compressed data generated a two-dimensional code called a quick response code (QR code). Results: Through the abovementioned converting process, it can be found that the number of bytes needed for storing P. ginseng chemical fingerprints and its DNA (ITS2) sequence code can be greatly reduced. After GTCA2Bytes algorithm processing, the ITS2 compression rate reaches 75% and the chemical fingerprint compression rate exceeds 99.65% via filtration and digital merger compression algorithm processing. Therefore, the overall compression ratio even exceeds 99.36%. The capacity of the formed QR code is around 0.5k, which can easily and successfully be read and identified by any smartphone. Conclusion: P. ginseng chemical fingerprints and its DNA (ITS2) sequence code can form a QR code after data processing, and therefore the QR code can be a perfect carrier of the authenticity and quality of P. ginseng information. This study provides a theoretical basis for the development of a quality traceability system of traditional Chinese medicine based on a two-dimensional code.

Confirmation of Drought Tolerance of Ectopically Expressed AtABF3 Gene in Soybean

  • Kim, Hye Jeong;Cho, Hyun Suk;Pak, Jung Hun;Kwon, Tackmin;Lee, Jai-Heon;Kim, Doh-Hoon;Lee, Dong Hee;Kim, Chang-Gi;Chung, Young-Soo
    • Molecules and Cells
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    • 제41권5호
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    • pp.413-422
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    • 2018
  • Soybean transgenic plants with ectopically expressed AtABF3 were produced by Agrobacterium-mediated transformation and investigated the effects of AtABF3 expression on drought and salt tolerance. Stable Agrobacterium-mediated soybean transformation was carried based on the half-seed method (Paz et al. 2006). The integration of the transgene was confirmed from the genomic DNA of transformed soybean plants using PCR and the copy number of transgene was determined by Southern blotting using leaf samples from $T_2$ seedlings. In addition to genomic integration, the expression of the transgenes was analyzed by RT-PCR and most of the transgenic lines expressed the transgenes introduced. The chosen two transgenic lines (line #2 and #9) for further experiment showed the substantial drought stress tolerance by surviving even at the end of the 20-day of drought treatment. And the positive relationship between the levels of AtABF3 gene expression and drought-tolerance was confirmed by qRT-PCR and drought tolerance test. The stronger drought tolerance of transgenic lines seemed to be resulted from physiological changes. Transgenic lines #2 and #9 showed ion leakage at a significantly lower level (P < 0.01) than ${\underline{n}}on-{\underline{t}}ransgenic$ (NT) control. In addition, the chlorophyll contents of the leaves of transgenic lines were significantly higher (P < 0.01). The results indicated that their enhanced drought tolerance was due to the prevention of cell membrane damage and maintenance of chlorophyll content. Water loss by transpiration also slowly proceeded in transgenic plants. In microscopic observation, higher stomata closure was confirmed in transgenic lines. Especially, line #9 had 56% of completely closed stomata whereas only 16% were completely open. In subsequent salt tolerance test, the apparently enhanced salt tolerance of transgenic lines was measured in ion leakage rate and chlorophyll contents. Finally, the agronomic characteristics of ectopically expressed AtABF3 transgenic plants ($T_2$) compared to NT plants under regular watering (every 4 days) or low rate of watering condition (every 10 days) was investigated. When watered regularly, the plant height of drought-tolerant line (#9) was shorter than NT plants. However, under the drought condition, total seed weight of line #9 was significantly higher than in NT plants (P < 0.01). Moreover, the pods of NT plants showed severe withering, and most of the pods failed to set normal seeds. All the evidences in the study clearly suggested that overexpression of the AtABF3 gene conferred drought and salt tolerance in major crop soybean, especially under the growth condition of low watering.

e-Business Security 프레임웍과 적용 방안 (e-Business Security Framework and applied to Architecture)

  • 홍승필;김명철;김재현;김민형
    • 융합보안논문지
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    • 제2권1호
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    • pp.87-97
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    • 2002
  • 인터넷의 발전과 더불어 빠르게 발전하는 e-Business 환경에서 그 편리함과 유익성에 반비례하여 위험/위협요소에 쉽게 노출되어지고 있다. e-Business 환경에서의 정보보안의 위협은 사용자의 실수등에 의한 사고에 의한 위협(Accidental Threats) 악의적 목적이나 영리추구를 위한 의도적인 위협(Intentional Threats)등으로 나뉘어 매우 빠르게 발생하고 있다. 이와 같이 점점 다양해지고 복잡해지는 e-Business 환경에서 가장 적합하고 안전한 정보보안 솔루션을 구현하기 위해서나, 또는 관련업체의 정보보안 장단점을 알아보기 위한 현황분석 등을 위하여 표준이나 기준이 될 수 있는 가이드라인이 필요하게 되었다. 이에 본 논문에서는 LG CNS에서 제시하는 정보보안의 프레임웍을 이용하여 e-Business 정보보안의 구현 방안에 대하여 설명하고자 한다. 이 프레임웍은 크게 정보보안의 기본전략, 메커니즘, 그리고 관리적 영역과 기술적 영역으로 나뉘어 보여지고 있다. 본 논문에서 제시되는 정보보안 프레임웍에 준하여, 실제 개발자나 정보보안 관련 엔지니어가 좀 더 쉽게 현존하는 시스템 환경에 적용하고 더 나아가 정보보안 구현의 초석이 될 수 있는 아키텍쳐를 소개하였다. 보안 아키텍처는 신뢰성 있는 보안 구현 방안을 제시하기 하기 위해, 네트워크/시스템 영역을 각각의 비즈니스 영역을 고려하여 구분하고, 이 영역별로 차별화 된 보안 솔루션을 구현하여 효과적인 보안구현 전략을 제시하는데 그 의의가 있다. 마지막으로 본 논문에서는 e-Business 환경에서의 통합 정보보안 솔루션을 기반으로 실제 e-Business 환경인 e-Marketplace중 Procurement에 적용될 수 있는 정보보안의 구현 사례를 제시하였다. 실 비즈니스 환경 분석을 통해 야기 될 수 있는 대표적인 위험/위협요소인 사용자 신분인증 및 문서의 위/변조등에 대응하여 적응되는 다양한 보안 솔루션 중 웹 기반에서의 사용자 인증통합 및 비즈니스적 연동이 빈번한 제휴 업체들과의 신뢰할 수 있는 접근통제가 요구되는 환경에서 프레임웍에 준하여 적용되어지는 사례 분석을 해 봄으로써 활용 가치를 증명해 보았다.

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지하수 과다유입 조건하에서의 터널굴착 (Tunneling in Severe Groundwater Inflow Condition)

  • 이용남;김대영
    • 한국지반환경공학회 논문집
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    • 제7권2호
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    • pp.67-76
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    • 2006
  • 본 논문은 수직 절리가 잘 발달된 지하수위가 높은 화산암질 지반에서 직경 3.3m의 도수터널 굴착을 하는 수력발전소 건설공사 내용이다. 취수시설은 발전소로부터 20.3km 상류에 위치하고 있으며, 20km의 도수터널과 연결되어 있고 440m의 낙차고를 갖는 펜스탁이 발전소와 연결되어 있다. 현장의 지질 조건은 전형적인 칼데라 호수인 토바호에 의해 지반 침식과 수직방향의 인장균열이 발달하였으며 이로 인해 지반의 초기응력이 이완되었다. 높은 지하수위(최대 수두 200m)를 가진 잘 발달된 수직 절리를 터널이 관통하면서 막대한 양의 지하수가 터널내로 유입되었다. 터널 굴착은 개방형 쉴드 TBM과 버럭반출에는 철로와 기관차를 사용하였다. 터널 내로의 유입수가 터널 바닥면에서 70cm 높이에 다다르고 이는 터널 직경(3.9m)의 17%에 해당하였다. 생산성을 향상하기 위해서 TBM과 버럭반출 차량과 같은 몇 가지의 개선과 수중펌프를 증설하는 방안을 사용하였다. 굴착 중에 만난 지반 조건이 설계보다 상당히 불량하여 RC라이닝에서 지하수 유입, 암반조건, 수압 등에 따라 PC 세그먼트 라이닝 또는 PC 세그먼트 라이닝과 현장타설 RC 라이닝, RC 라이닝, 그리고 강재 라이닝이 적용되었다. 이 PC 세그먼트 라이닝의 도입과 TBM과 다른 장비의 개조 및 개선을 통해서 심각한 지하수 조건 하에서 터널 굴착 공사를 성공적으로 완료하였다.

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PS-Net : 개인별 보안 Wi-Fi 네트워크 (PS-Net : Personalized Secure Wi-Fi Networks)

  • 이남세;이주호;정충교
    • 한국통신학회논문지
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    • 제40권3호
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    • pp.497-505
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    • 2015
  • 기존의 보안 Wi-Fi 네트워크는 사용자가 AP(Access Point)의 암호에 맞춰야 하므로 사용이 불편하며, 사용자들이 암호를 공유하므로 시간이 갈수록 보안성이 낮아지는 문제점을 갖고 있다. 이를 해결하기 위해 사용자마다 별도의 가상 Wi-Fi 네트워크를 할당하는 방안을 제안한다. 이 방법에서는 각 사용자가 자신만의 Wi-Fi 네트워크를 가지므로 사용자 중심의 네트워크 설정이 가능하다. 사용자는 자신의 기기에 나름대로의 SSID(Service Set IDentifier)와 암호를 미리 설정해 두며 AP는 자신의 공개키를 적절한 방법으로 공개한다. AP는 또한 사용자들이 언제나 접속할 수 있는 공개채널을 유지한다. 사용자 요청이 있을 때 사용자 기기는 연결 요청 메시지를 보내는데 이 메시지에는 AP의 공개키로 암호화된 사용자 기기의 SSID와 암호가 실려 있다. 연결 요청 메시지를 받은 AP는 해당 SSID 및 암호가 설정된 새로운 가상의 AP를 생성하는데 이 가상 AP는 해당 사용자만 사용할 수 있는 전용 AP라고 할 수 있다. 이렇게 만들어지는 가상 네트워크는 비밀번호를 여러 사용자가 공유하지 않으므로 보안성이 높다. 또 이 가상 네트워크는 네트워크가 사용자 기기에 맞춰 스스로를 설정하기 때문에 사용의 편의성이 높다. 새 방법이 제공하는 보안성과 편리성에도 불구하고 기존의 Wi-Fi 네트워크에 비해 별다른 전송 능력 저하는 나타나지 않음을 실험을 통해 확인하였다.

한국의 교도소도서관 현황분석과 개선방안 (Analysis of the Current Situation and Improvement Method of Correctional Facility Libraries in Korea)

  • 권세희;윤혜영
    • 정보관리연구
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    • 제40권3호
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    • pp.125-150
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    • 2009
  • 이 연구의 목적은 인권의 사각지대에 있는 교정시설 내에 구금된 수용자들을 대상으로 정보를 제공하는 교도소도서관의 현황을 분석하여 그 문제점을 도출하고 개선방안을 제시하는 것이다. 교도소도서관 현황을 파악하기 위하여 시설 및 설비와 인적 자원, 보유도서현황과 대출현황 그리고 예산현황 등에 이르기까지 종합적으로 통계자료를 토대로 정리 분석하였다. 문화체육관광부의 국가도서관 통계시스템사이트(2008년 기준: 2007년 $1{\sim}12$월 조사)와 2008년 발간한 '도서관발전종합계획(2009-2013)', 교도소에 정보공개청구를 통하여 얻은 '관용도서 비치 및 활용현황' 문서 34건을 이용하여 교도소도서관의 시설, 인적 자원, 장서, 서비스, 예산 등의 실태를 조사하였다. 이러한 현황 조사내용을 토대로 하여 한국교도소도서관의 문제점을 추출해 보고 이에 대한 발전방향을 모색하였다.