• Title/Summary/Keyword: Open-gap

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Growth of CaAl2Se4: Co Single Crystal Thin Film for Solar Cell Development and Its Solar Cell Application (태양 전지용 CaAl2Se4: Co 단결정 박막 성장과 태양 전지로의 응용)

  • Bang, Jin-Ju;Hong, Kwang-Joon
    • Journal of the Korean Solar Energy Society
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    • v.38 no.1
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    • pp.25-36
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    • 2018
  • The stoichiometric mixture of evaporating materials for the $CaAl_2Se_4$: Co single crystal thin film was prepared from horizontal furnace. Using extrapolation method of X-ray diffraction patterns for the polycrystal $CaAl_2Se_4$, it was found orthorhomic structure whose lattice constant $a_0$, $b_0$ and $c_0$ were 6.4818, $11.1310{\AA}$ and $11.2443{\AA}$, respectively. To obtain the $CaAl_2Se_4$: Co single crystal thin film, $CaAl_2Se_4$: Co mixed crystal was deposited on throughly etched Si (100) by the HWE (Hot Wall Epitaxy) system. The source and substrate temperature were $600^{\circ}C$ and $440^{\circ}C$ respectively. The crystalline structure of $CaAl_2Se_4$: Co single crystal thin film was investigated by the double crystal X-ray diffraction (DCXD). Hall effect on this sample was measured by the method of Van der Pauw and studied on carrier density and mobility depending on temperature. From Hall data, the mobility was likely to be decreased by impurity scattering in the temperature range 30 K to 100 K and by lattice scattering in the temperature range 100 K to 293 K. The temperature dependence of the energy band gap of the $CaAl_2Se_4$: Co obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=3.8239eV-(4.9823{\times}10^{-3}eV/K)T_2/(T+559K)$. The open-circuit voltage, short current density, fill factor, and conversion efficiency of $p-Si/p-CaAl_2Se_4$: Co heterojunction solar cells under $80mW/cm^2$ illumination were found to be 0.42 V, $25.3mA/cm^2$, 0.75 and 9.96%, respectively.

Community Structure Analysis of Carpinus laxiflora Communities in Seoul (서울지역 서어나무림의 군집구조 분석)

  • Park, Byung-Chang;Oh, Choong-Hyeon;Cho, Chi-Woung
    • Korean Journal of Environment and Ecology
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    • v.23 no.4
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    • pp.333-345
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    • 2009
  • Carpinus laxiflora communities are known as the climax forest community of the temperate zone of Korea. There are three Carpinus laxiflora communities in Seoul. The purpose of this research is to analyze the characteristics of Carpinus laxiflora communities of Seoul and supply basic data for establishing of a management plan. The research sites are Sahmyook University, Mountain Dobong and Jinkwandong. This study considers investigation and the analysis of communities structure, soil characteristics and the growth increment of trees. As the result of study, we could know that the growth increment of the Carpinus laxiflora trees of Seoul is decreasing recently because of soil acidification and so on. Also the vegetation disturbance is increasing because of naturalized plant. Oak wilt disease has appeared in the oak forest around Sahmyook University that is the largest Carpinus laxiflora communities area in Seoul. For that reason the open gap was appeared in forest, and the spread of naturalized plants has been increasing in the gap. Furthermore, the Carpinus laxiflora trees are affected by the Platypus koryoensis which is a kind of oak wilt disease. And so, Unless there is a specific management plan, the survival of Carpinus laxiflora communities are uncertain in Seoul. Therefore the management plan of Carpinus laxiflora communities is necessary such as precise investigation, annual monitoring, etc. For the conservation of the Carpinus laxiflora communities, it is necessary to establish the management plan of the biodiversity for Seoul area.

The Interpretation of Sosoewon from the Perspective of Reception Aesthetics (소쇄원의 수용미학적 해석)

  • Seo, Jayoo
    • Journal of the Korean Institute of Landscape Architecture
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    • v.49 no.3
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    • pp.29-39
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    • 2021
  • This study interpreted a traditional garden of Korea through reception aesthetics. The 'gap' of acceptable aesthetics is found in the 'distance that occurs between writers and readers'. This study aims to interpret this gap between what the writer intends and what the reader expects. Boundaries do not limit traditional spaces in Korea and, therefore, are not limited by characteristics. These characteristics were studied from the perspectives of the author, the work, and the reader. The aspect first looked at the life and ideas of the gardener, the second analyzed the form and structure of the garden, and the last examined writings, from the past and present, of those who appreciated the garden. From the author's perspective, Sosoewon was understood as a garden that embodied the philosophy of Yang Sanbo. Second, the duality and indeterminateness were recognized as two characteristics of this work; artifacts in the garden were arranged in a natural form, and the gardens have indefinite boundaries, so they can be freely expanded and reduced. Finally, from the reader's perspective, it was noted that the beauty of this garden is enhanced through poetry, painting, and writing. Thus, historic gardens of Korea can be open spaces where the meaning of the garden is enriched through the free participation of viewers based on their own ideas.

A Study on the Plans for Effective Use of Public Data: From the Perspectives of Benefit, Opportunity, Cost, and Risk (인터넷기반 공공데이터 활용방안 연구: 혜택, 기회, 비용, 그리고 위험요소 관점에서)

  • Song, In Kuk
    • Journal of Internet Computing and Services
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    • v.16 no.4
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    • pp.131-139
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    • 2015
  • With the request for the advent of new engine toward economic growth, the issue regarding public-owned data disclosure has been increasing. The Korean governments are forced to open public-owned data and to utilize them in solving the various social problems and in promoting the welfare for the people. In contrast, due to the distrust of the effectiveness for the policy, many public owned organizations hesitate to open the public-owned data. However, in spite of communication gap between the government and public organizations, Ministry of Government Administration and National Information Society Agency recently planned to accelerate the information disclosure. The study aims to analyze the perception of the public organization for public data utilization and to provide proper recommendations. This research identified mutual weights that the organization recognize in opening and sharing the public data, based on benefit, opportunity, cost, and risk. ANP decision making tool and BOCR model were applied to the analyses. The results show that there are significant differences in perceiving risk and opportunity elements between the government and public organizations. Finally, the study proposed the ideal alternatives based on four elements. The study will hopefully provide the guideline to the public organizations, and assist the related authorities with the information disclosure policy in coming up with the relevant regulations.

Bone-level implants placed in the anterior maxilla: an open-label, single-arm observational study

  • Gao, EnFeng;Hei, Wei-Hong;Park, Jong-Chul;Pang, KangMi;Kim, Sun Kyung;Kim, Bongju;Kim, Soung-Min;Lee, Jong-Ho
    • Journal of Periodontal and Implant Science
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    • v.47 no.5
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    • pp.312-327
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    • 2017
  • Purpose: This study assessed marginal bone remodeling and soft tissue esthetics after the loading of single bone-level implants in the anterior maxilla. Methods: An open, single-arm observational clinical trial with 3 years of follow-up was performed, including 22 implants. The patients presented with a single tooth gap in the anterior maxilla (tooth positions 14-24), with natural or restored adjacent teeth. An implant was placed at least 8 weeks post-extraction and healed submerged for 6 weeks. After the second-stage operation, a fixed provisional prosthesis was provided. The final restoration was placed 6 months after the provisional restoration. The time of the provisional crown connection was considered to be the baseline in this study. Esthetic parameters and the marginal bone level were assessed at 6, 12, 24, and 36 months. Results: All implants were well integrated in the bone. A statistically significant increase was found in the mean implant stability quotient between the time of the provisional prosthesis and the time of the final prosthesis. Most implants (95.5%) revealed marginal bone resorption (<0.5 mm), and just 1 implant (4.5%) showed a change of 2.12 mm from baseline to 36 months (mean $0.07{\pm}0.48mm$), while the crestal bone level decreased significantly, from $2.34{\pm}0.93mm$ at baseline to $1.70{\pm}1.10mm$ at 36 months. The facial gingival margin and papilla were stable and the esthetic scores indicated high patient and dentist satisfaction. Conclusions: Platform-switching bone-level implants placed in maxillary single-tooth gaps resulted in successful osseointegration with minimal marginal bone resorption. The peri-implant soft tissue was also esthetically satisfying and stable.

A Study on Arbitration Qualification of Intellectual Property Right Dispute - Focus on Korea and China - (지적재산권분쟁의 중재적격에 관한 연구 -한국과 중국을 중심으로-)

  • Choi, Song-Za
    • Journal of Arbitration Studies
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    • v.21 no.2
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    • pp.27-46
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    • 2011
  • In the intellectual based society of the 21th century, intellectual property of nation and enterprise management has been the key element of nation's competitiveness and development. Therefore in countries like Korea, China, and many other countries, intellectual property of advancement strategy are being constructed and intellectual properties are protected at national level. Top priority task of protecting the intellectual property is to efficiently resolute intellectual property right disputes. Considering the nature of intellectual property right and arbitrage system, arbitration to solve intellectual property disputes is realistically the best method. However, not all cases of them are qualified. In order to relieve the intellectual property disputes through arbitration, qualification must be obtained. During the process, generally and globally, intellectual property right dispute is evaluated by three parts, intellectual property right contract dispute, intellectual property right violation dispute, and intellectual property right validity dispute. Based on UN's "Convention on the Recognition and Enforcement of Foreign Arbitral Awards Agreement" in 1958, June 10th, in New York, both arbitrage organization and judgment can be approved in both Korea and China countries. However, as of today, there is a big gap of arbitration qualification between two countries, which can be troublesome if intellectual property right disputes arise. For instance, in Korea, intellectual property right contract disputes and intellectual property right violation disputes are both generally accepted as arbitration qualification. However for intellectual property right validity dispute, arbitration qualification is only accepted for non-registered intellectual property as in copyright entity. It does not apply to other registered intellectual property right as in patents. In China, arbitration qualification is accepted for intellectual property right contract dispute, and also accepted for intellectual property right violation dispute to copyrights but restricted to others. As for intellectual property right validity dispute, arbitration qualification is completely denied. Therefore, when there is an intellectual property right dispute between Korea and China, the biggest problem is whether China will accept arbitrage judgments made in Korea. Theoretically, arbitrage judgement made in Korea should be also accepted in China's court. However, considering the criticism of China's passive nature of arbitration qualification for its own local intellectual property right disputes, it's very unlikely they'll actively accept arbitrary judgment made in foreign countries. Korea and China must have a more open minded approach for intellectual property disputes and arbitration qualification. Base on WTO's Intellectual Property Right Agreement, it's being defined as private right. Therefore, sovereign principle should be the basic principle of solving intellectual property right disputes. Currently, arbitration qualification is expanding internationally. So both Korea and China must also follow the trend expand the arbitration qualification with a more open minded and forward looking approach, for the good of intellectual property disputes.

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TYPE II DENTINOGENESIS IMPERFECTA : CASE REPORT (Type II 상아질형성부전증의 임상 증례)

  • Kim, Chi-Hyun;Lee, Jae-Ho;Choi, Byung-Jai;Lee, Chong-Gap
    • Journal of the korean academy of Pediatric Dentistry
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    • v.28 no.4
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    • pp.654-660
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    • 2001
  • Dentinogenesis imperfecta is an example of an inheritable dentinal defect originating during the histodifferentiation stage of tooth development, with involvement of the primary and permanent teeth. Shields, Bixler and El-Kafrawy proposed three types of Dentinogenesis imperfecta : Type I, II, III. Witkop reported a prevalence of 1 in 8000 with the trait, and no significant difference between male and female. Affected teeth have red-brown discoloration often with distinctive wearness of occlusal surface of posterior teeth and incisal surface of anterior teeth. Once enamel seperated from underlying defective dentin, the dentin demonstrates significantly acclerated attrision. Radiographically, the teeth have thin roots, bulbous crown, cervical constriction, and obliteration of the root canals and pulp chambers. In primary dentition periapical lesions or multiple root fractures are often observed. In successive generations the phenotypes of discoloration and wearness of teeth occurred, and one of the patient's subships, 10 year-old sister, showed general discoloration of her teeth and mild wearness. In this case, a 4 year-old male reported to the Yonsei University Pedodontics clinic, with a chief complaint of discolored teeth. The teeth showed generally yellowish-brown discoloration and moderate wearness. In radiographic features, obliteration of pulp, bulbous crown, and short roots were observed. It was diagnosed as Dentinogenesis imperfecta. The posterior teeth were restored with Stainless Steel Crown, and defective incisors including left upper primary central incisor which was extracted due to a root fracture with Open-faced Stainless Steel crown.

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The Improvement of Point Cloud Data Processing Program For Efficient Earthwork BIM Design (토공 BIM 설계 효율화를 위한 포인트 클라우드 데이터 처리 프로그램 개선에 관한 연구)

  • Kim, Heeyeon;Kim, Jeonghwan;Seo, Jongwon;Shim, Ho
    • Korean Journal of Construction Engineering and Management
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    • v.21 no.5
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    • pp.55-63
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    • 2020
  • Earthwork automation has emerged as a promising technology in the construction industry, and the application of earthwork automation technology is starting from the acquisition and processing of point cloud data of the site. Point cloud data has more than a million data due to vast extent of the construction site, and the processing time of the original point cloud data is critical because it takes tens or hundreds of hours to generate a Digital Terrain Model (DTM), and enhancement of the processing time can largely impact on the efficiency of the modeling. Currently, a benchmark program (BP) is actively used for the purpose of both point cloud data processing and BIM design as an integrated program in Korea, however, there are some aspects to be modified and refined. This study modified the BP, and developed an updated program by adopting a compile-based development environment, newly designed UI/UX, and OpenGL while maintaining existing PCD processing functions, and expended compatibility of the PCD file formats. We conducted a comparative test in terms of loading speed with different number of point cloud data, and the results showed that 92 to 99% performance increase was found in the developed program. This program can be used as a foundation for the development of a program that reduces the gap between design and construction by integrating PCD and earthwork BIM functions in the future.

Clinical and Radiological Outcomes of Foraminal Decompression Using Unilateral Biportal Endoscopic Spine Surgery for Lumbar Foraminal Stenosis

  • Kim, Ju-Eun;Choi, Dae-Jung;Park, Eugene J.
    • Clinics in Orthopedic Surgery
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    • v.10 no.4
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    • pp.439-447
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    • 2018
  • Background: Since open Wiltse approach allows limited visualization for foraminal stenosis leading to an incomplete decompression, we report the short-term clinical and radiological results of unilateral biportal endoscopic foraminal decompression using $0^{\circ}$ or $30^{\circ}$ endoscopy with better visualization. Methods: We examined 31 patients that underwent surgery for neurological symptoms due to lumbar foraminal stenosis which was refractory to 6 weeks of conservative treatment. All 31 patients underwent unilateral biportal endoscopic far-lateral decompression (UBEFLD). One portal was used for viewing purpose, and the other was for surgical instruments. Unilateral foraminotomy was performed under guidance of $0^{\circ}$ or $30^{\circ}$ endoscopy. Clinical outcomes were analyzed using the modified Macnab criteria, Oswestry disability index, and visual analogue scale. Plain radiographs obtained preoperatively and 1 year postoperatively were compared to analyze the intervertebral angle (IVA), dynamic IVA, percentage of slip, dynamic percentage of slip (gap between the percentage of slip on flexion and extension views), slip angle, disc height index (DHI), and foraminal height index (FHI). Results: The IVA significantly increased from $6.24^{\circ}{\pm}4.27^{\circ}$ to $6.96^{\circ}{\pm}3.58^{\circ}$ at 1 year postoperatively (p = 0.306). The dynamic IVA slightly decreased from $6.27^{\circ}{\pm}3.12^{\circ}$ to $6.04^{\circ}{\pm}2.41^{\circ}$, but the difference was not statistically significant (p = 0.375). The percentage of slip was $3.41%{\pm}5.24%$ preoperatively and $6.01%{\pm}1.43%$ at 1-year follow-up (p = 0.227), showing no significant difference. The preoperative dynamic percentage of slip was $2.90%{\pm}3.37%$; at 1 year postoperatively, it was $3.13%{\pm}4.11%$ (p = 0.720), showing no significant difference. The DHI changed from $34.78%{\pm}9.54%$ preoperatively to $35.05%{\pm}8.83%$ postoperatively, which was not statistically significant (p = 0.837). In addition, the FHI slightly decreased from $55.15%{\pm}9.45%$ preoperatively to $54.56%{\pm}9.86%$ postoperatively, but the results were not statistically significant (p = 0.705). Conclusions: UBEFLD using endoscopy showed a satisfactory clinical outcome after 1-year follow-up and did not induce postoperative segmental spinal instability. It could be a feasible alternative to conventional open decompression or fusion surgery for lumbar foraminal stenosis.

A Study on Library Policy and Performance Analysis to Practice Social Inclusion (사회적 포용을 실천하기 위한 도서관 정책 및 성과 분석에 관한 연구)

  • Noh, Younghee;Shin, Youngji
    • Journal of the Korean Society for Library and Information Science
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    • v.55 no.4
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    • pp.245-266
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    • 2021
  • In this study, in order to practice the social inclusion of libraries, the related policies currently announced in the 3rd Comprehensive Library Development Plan were examined, and the current status of tasks promoted by central administrative agencies and metropolitan and provincial libraries was examined based on these policies. As a result, first, in terms of active information welfare realization, various programs and services are being implemented to bridge the knowledge and information gap, but it seems that the scope of the target should be expanded in the future, cooperation with related organizations, and infrastructure improvement. Second, in terms of expanding the openness of the space, the expansion of the open space as an open space and the application of universal design are being performed. In the future, it seems that the scope of universal design application should be expanded in consideration of budget investment for continuous space reconstruction and diversity of users. Third, in terms of linking services across boundaries, services and programs are provided to infants and toddlers, children, women, the elderly, the underprivileged, job seekers, and multicultural families. In the future, it seems that the improvement of the service system for the expansion of inclusive services in libraries should precede, and cooperation between related ministries should be made to provide differentiated services. Finally, it is expected that future policy-making tasks for social inclusion should be considered not only for books, programs, and spaces, but also for librarians' education, establishment of cooperative networks with related organizations, and marketing for services and programs.