• Imaging Science in Dentistry
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• 제33권3호
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• pp.137-141
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• 2003

Purpose: To evaluate the precision of measurements taken of dental implants in bucco-lingually sectioned views of the maxilla by linear tomograms of the panorama and to assess the visibility of the inferior wall of the maxillary sinus. Materials and Methods : Eighty sites prepared with implants of gutta percha cone in the sockets of the upper premolars and molars of 10 dry skulls were radiographically examined using linear tomograms of panorama, and scanned coronally and axially by computed tomography. The differences in mm between the measurements in bucco-lingually sectioned images of maxillary alveolar bone and the true length and width of the implanted gutta percha cones were compared as mean values (mean) and standard deviations (SD) for each radiographic technique. Linear tomography of panorama was compared with computed tomography for visualization of the relationship between the inferior wall of maxillary sinus and the end of each implant. Results: The deviations between the actual implant length and the measured values taken from the linear tomograms (0.44±0.39 mm) was significantly less than the measured values from the multiplanar reconstructed images of the axially scanned computed tomogram (1.21 ± 0.90 mm). There was statistically significant difference (p < 0.05) between two techniques in the differences between the measurements and true implant length. The relationship of the inferior border of maxillary sinus with end of implant was worse identified with the linear tomogram of panorama (68%) than the multiplanar reconstructed image of axially scanned computed tomogram (99%). Conclusion: We could not find any differences in the accuracy of length measurement between the linear tomogram of panorama and computed tomogram, but computed tomogram allowed for a better visualization of the inferior wall of the maxillary sinus than the linear tomogram.

• Imaging Science in Dentistry
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• 제47권1호
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• pp.39-44
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• 2017

Purpose: Insufficient knowledge of the anatomy of the maxillary sinuses prior to sinus graft surgery may lead to perioperative or postoperative complications. This study sought to characterize the position of the posterior superior alveolar artery (PSAA) within the maxillary sinuses using cone-beam computed tomography (CBCT). Materials and Methods: A total of 300 patients with edentulous posterior maxillae, including 138 females and 162 males with an age range of 33-86 years, who presented to a radiology clinic between 2013 and 2015 were enrolled in this retrospective cross-sectional study. The distance from the inferior border of the PSAA to the alveolar crest according to the residual ridge classification by Lekholm and Zarb, the distance from the PSAA to the nasal septum and zygomatic arch, and the diameter and position of the PSAA were all assessed on patients' CBCT scans. The data were analyzed using the Mann-Whitney test and the t-test. Results: The PSAA was detected on the CBCT scans of 87% of the patients; it was located beneath the sinus membrane in 47% of cases and was intraosseous in 47% of cases. The diameter of the artery was between 1 and 2 mm in most patients (72%). The mean diameter of the artery was $1.29{\pm}0.39mm$, and the mean distances from the PSAA to the zygomatic arch, nasal septum, and alveolar crest were $22.59{\pm}4.89mm$, $26.51{\pm}3.52mm$, and $16.7{\pm}3.96mm$, respectively. Conclusion: The likelihood of detecting the PSAA on CBCT scans is high; its location is intraosseous or beneath the sinus membrane in most patients. Determining the exact location of the PSAA on CBCT scans preoperatively can help prevent it from being damaged during surgery.

• 한국결정성장학회지
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• 제16권2호
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• pp.71-75
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• 2006

소성 분위기를 변화시켜 골재를 제조할 때 골재의 중앙에 만들어지는 블랙코어(black core) 형성정도의 차이와 골재 물성의 차이점을 알아보기 위해 적점토, 탄소(carbon), 산화철($Fe_2O_3$)이 혼합된 직경 10mm 구형골재를 조성별로 산화분위기, 중성분위기, 환원분위기에서 각각 소성시키고 각각의 비중, 흡수율, 블랙코어 면적비(%)를 측정하고 비교하였다. 산화분위기에서 소성시킨 골재는 껍질(shell)과 블랙코어가 뚜렷하게 구분되는 반면 중성 및 환원분위기에서 소성한 시편에서는 시편의 단면전체에 블랙코어가 형성되었다. 산화분위기와 중성분위기와는 달리 환원분위기에서 소성된 시편에서는 탄소첨가량이 증가할수록 비중이 증가했으며, 전반적인 비중은 가장 낮았다. 흡수율은 모든 분위기에서 탄소첨가량이 증가할수록 증가하는 경향을 보였다.

• 통상정보연구
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• 제12권1호
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• pp.3-33
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• 2010

Paperless trade is a new trade paradigm that has innovated on traditional trade procedures, which relied on manual work in the past, and applied an IT-based e-document standard. To realize paperless trade in Korea, a lot of efforts have been made. Korea has overcome many difficulties, a lack of awareness, trials and errors, etc. at the initial introduction stage and strived to establish a stable infrastructure through the government's policy support and active cooperation with the trade business communities and related organizations. Now, Korea became a well-known leader in IT industry, especially in the paperless trade infrastructure and strategic policies. The one-stop trading system named 'uTradeHub' is operated by a paperless trade service provider, Korea Trade Network(KTNET). uTradeHub includes trade finance and settlement, customs clearance and export and import logistics, improving trading procedures and reducing related expenses. Private-Public joint efforts from Korean government and private sectors which have respectively fulfilled their role and function with market-oriented practical policies and strategies has lead Korea a world leading country in paperless trade. Moreover, Korea expended its efforts to the global areas. Korea has started to activate multi-national paperless trade alliances such as PAA(Pan-Asia e-Commerce Alliance), ASEAL(Asia Europe Alliance for Paperless Trading) as well as established the bilateral cooperative networks with China and Taiwan. The one-stop trading system, uTradeHub should keep close cooperations between nations since trade itself is implemented in a cross-border ways. In the near future, it is expected uTradeHub can achieve best results in the simplification of procedures and cost savings when an international linkage is completely established with international cooperations.

• 항공우주산업기술동향
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• 제7권2호
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• pp.3-11
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• 2009

올해 8월 25일, 한국은 최초의 소형위성탑재 발사체인 KSLV-1(나로호)를 발사했다. 발사체의 1단과 2단이 각각 정상적으로 작동했다는 점에서 발사 자체는 성공적이었으나, 위성은 노즈 페어링 분리 실패로 인해 궤도 진입에 실패했다. 물론, 인류의 우주개발 역사에서 보듯이, 발사국이 된다는 것은 어려운 과업임에 틀림없다. 이를 성공하기 위해서 많은 기술적 난제들이 해결되어야 하며 이를 위해 연구원 및 기술자들이 발사체를 발사할 수 있는 기술적인 능력을 확보하기 위해 노력하고 있는 것이다. 하지만, 발사국이 되기 위 해서는 기술력만 확보해서 되지는 않으며, 국제사회에서 통용되는 법규범에 대한 이해가 같이 되어야 한다. 특히 발사시 만약의 경우 국경을 넘어서는 피해가 발생할 수도 있다는 점에서, 또한 발사체기술이 전략기술 에 해당된다는 점에서 국제법규범에서 자유로울 수 없는 것이다. 본 논문에서는 발사체를 개발, 운용하는 발사국의 국제법적 지위를 검토하고, 발사체 개발에 따라 고려해야 하는 국제법체제를 정리하고자 한다.

• 한국지역지리학회지
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• 제12권6호
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• pp.656-670
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• 2006

우리나라 대다수의 농촌 지역에서는 초 중등학교 학생 수 감소에 따라 교육기반이 붕괴 위기에 직면해 있으나, 경남 거창군에서는 외부에서 유입한 학생 수가 전체 고등학교 학생 수의 약 25%에 달하는 특이한 현상이 나타나고 있다. 거창군의 중등교육세력권은 1980년대에는 거창군의 접경지역에만 국한되었으나, 1990년대에 들어서부터 점차 전국적으로 확대되었다. 그러나 거창군의 중등교육세력권 확대는 전국적인 명문 고등학교로서의 위상을 확보한 사립 인문계 고등학교인 거창고등학교와 거창대성고등학교에 제한된 현상이라는 점에서 거창군 교육세력권은 불완전한 전국화로 특징지을 수 있다. 이러한 거창군 교육세력권의 시 공간적 변화에는 교육 정책 및 제도의 변화와 학교별 특성이 주요한 요인으로 작용하였다.

• 한국환경복원기술학회지
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• 제20권6호
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• pp.161-180
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• 2017

As the competition for securing cross-border biological sovereignty becomes intensified due to the adoption of the Nagoya Protocol, this study analyzed patent trends only for freshwater plants in order to secure national biological sovereignty. As a result, freshwater plants include a total of 68 genera and 128 species, and a total of 60 genera and 3,256 patents were surveyed. Among them, iris was the most industrialized, 14.71% followed by angelica(8.48%) and Mentha(6.94%). However, unconfirmed eight genera (Aneilema, Artemisia Cabomba, Nymphoides, Pistia stratiotes L., Pseudoraphis Griff., Ruppia) are not patented freshwater plants and it is expected that patent entry is high and barrier is low in the future. Based on patent results, Cooperative Patent Classification analysis was carried out and as a result, a total of 15 industry sectors were derived. And biopharmaceutical(30.24%) was found to be the most industrialized industry sector followed by agricultural chemistry (28.89%), biochemical industry (16.25%). In the biomedical industry, angelica(17.74%) was the most used and Iris (9.55%), Sium(20.56%) and angelica (20.48%) were found to be the most used in agricultural chemistry, biochemical industry and bio food industry, respectively. The analysis of detailed industry fields for 15 industry sectors showed that medicines of unknown structure containing substances from plants (37.77%), raw materials (46.57%) such as insect repellants, attracting agents and preparation of peptides(16.82%) with more than 21 amino acids were most frequently used in biopharmaceutical, agricultural chemistry and biochemical industry, respectively. This study is of significance as a basic data to know which freshwater plants are used in which field in order to secure biological sovereignty and patent analysis is considered necessary to continuously secure the biological sovereignty for freshwater plants.

• Asian Pacific Journal of Cancer Prevention
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• 제16권7호
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• pp.3051-3056
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• 2015

Background: Skin self-examination (SSE) may facilitate early diagnosis of melanoma at a potentially curable stage. Little data are available concerning the SSE frequency and knowledge about the symptoms of melanoma in non-patient populations. The aim of our study was to assess the performance of skin self-examination, recognition of potential melanoma symptoms as well as behavior related to sun exposure among web users in Poland. Materials and Methods: A cross-sectional study was conducted among readers of a scientific portal. Invited respondents were asked to complete an online questionnaire. Finally, statistical analysis was conducted on 4,919 surveys towards potential clinical signs of melanoma and SSE performance. Results: Approximately 60% of respondents had ever performed SSE in their life. Only 18.4 % declared performance on a regular, monthly, basis. Factors promoting this activity were established to be bigger place of residence, higher education and sensitive skin phototype, higher level of knowledge concerning melanoma, safe tanning rules and, especially, past surgical excision of naevi. Declared longer use of tanning beds was linked to understanding better the importance of clinical features of melanoma. Awareness of hazardous behavior during sunbathing is associated with the attempts to change them. Conclusions: Regular SSE is not a common practice, whilst the knowledge about the clinical features of melanoma is varied. Therefore, constant pressure should be put on promotion of regular skin self-examination and teaching its proper techniques, including familiarity with the ABCD (asymmetry; border; color; diameter) rule and its extension of "EFG" (elevated, firm, progressive growth) criteria.

• 디지털융복합연구
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• 제12권6호
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• pp.559-568
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• 2014

오늘날과 같은 다매체 시대에서는 미디어의 형태(하드웨어)보다 미디어의 내용(콘텐츠)이 성패를 좌우한다고 해도 과언이 아닐 정도로 콘텐츠가 중요한 요소로 작용한다. 인기 있는 텔레비전 프로그램들은 국경을 넘어 공급되고 현지 시청자들에 맞게 각색된 이른바 '포맷'이라는 형태로 확산되고 있다. 이러한 포맷산업은 미국에서 시작되었지만 1990년대부터 유럽으로 주도권이 옮겨지게 되었고, 이후 "super-formats"에 의해 확고하게 자리잡은 산업이며 오늘날 연간 31억 유로로 추정되는 가치를 지니고 있다. 특히 2000년대 이후 세게 방송포맷산업의 중심지로 떠오른 영국의 사례는 문화콘텐츠산업을 육성하고자 하는 한국에 시사하는 바가 크다고 할 수 있다. 본 연구는 이러한 방송포맷산업의 역사를 연대기적으로 고찰하고 콘텐츠 강국으로서의 영국이 가진 산업적 배경을 살펴봄으로써 한국의 콘텐츠산업에 시사하는 바를 찾고자 함에 그 목적이 있다.

• 대한지리학회지
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• 제48권1호
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• pp.72-86
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• 2013

산업집적은 경제지리학에서 오랫동안 연구되어온 주제 중의 하나이며 지금까지 다양한 방법을 통해 산업집적 현상을 설명하고 이의 영향을 평가해왔다. 하지만 시계열 데이터를 이용해 집적의 추이를 살펴본 연구는 아직 활발히 이루어지지 않고 있다. 본 연구는 지난 29년 간의 데이터를 이용해 사례로 선정된 산업들의 집적 정도를 평가하고 이러한 시계열 패턴과 도로 네트워크의 확장이 어떠한 인과관계를 맺고 있는 지 살펴보고 있다. 집적 정도를 측정한 결과 사례로 선정된 산업의 종사자들은 지리적으로 균등하게 분포되지 않고 있었다. 또한 사례 산업들 간에 공통된 시계열적 변화 특성은 나타나지 않았으나 각 산업의 발전 단계 및 비즈니스 환경 변화가 개별 산업의 집적 정도에 영향을 주고 있는 것으로 보이고 있다. 집적 정도와 도로교통망 사이의 관계를 살펴보기 위해 각 산업 별로 Granger causality test를 실시하였고 도로 교통망이 산업 집적에 영향을 주고 있음을 몇몇 사례를 통해 확인할 수 있었다. 그러나 이와 반대의 경우 혹은 상호 간에 영향을 주는 사례도 나타나 교통망과 산업집적이 보다 복잡한 관계를 맺고 있음을 보여준다.