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A Study on Under Keel Clearance of Gadeok Channel for the Safety Passage of Mega Container Ship (초대형 컨테이너선의 가덕수로 안전운항을 위한 선저여유수심 연구)

  • Ryu, Won;Kong, Suk-Young;Lee, Yun-Sok
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.6
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    • pp.789-797
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    • 2021
  • The worldwide sizes of container ships are rapidly increasing. The container ship size in 2005, which was about 9,200 TEU has increased to 24,000 TEU in recent times. In addition to the increase in the sizes of the container ships, the arrivals/departures of large container vessels to/from Korea have also increased. Hence, the necessity for reviewing safe passage of such vessels is emphasized. In the present study, a 24,000 TEU container vessel was used as a model ship to calculate the under-keel clearance (UKC) at Gadeok Channel through which vessels must pass to arrive at Busan New Port, in accordance with the Korean Port and Fishing Port Design Standards and Commentary. In addition, the maximum allowable speed that meets UKC standards was calculated using various squat formulas, whose results were then compared with the current speed limit standards. The analysis results show that Busan New Port requires 10% marginal water depth, and the squat that meets this requirement is 0.95 m. Gadeok Channel requires 15% marginal water depth, and the squat that meets this requirement is 1.78 m; in this case, the maximum allowable speed is calculated as 15 kts. Busan New Port has set the speed limit as 12 kts, which is higher than the calculated 11 kts. Thus, speed limit reconsideration is required in terms of safety. However, the set speed limit for Gadeok Channel is 12 kts, which is lower than the calculated 15 kts. Thus, additional considerations may be provided to increase the speed limits for smooth navigational passage of vessels. The present study, however, is constrained by the fact that it reflects only a limited number of elements in the UKC and allowable speed calculations; therefore, more accurate UKC and safe speed values can be suggested based on extended studies to this research.

Development of Vivorium, a new indoor horticultural ornamental plants via plant tissue culture techniques (식물조직배양 기술을 이용한 새로운 실내 원예 장식품인 비보리움(Vivorium)의 개발)

  • Hwang, Min Hee;Kim, Do Yeon;Cho, In Sun;Kim, Mi Hyung;Kwon, Hyun Sook;Kim, Jong Bo;Kim, Su Jung;Kim, Sun Hyung
    • Journal of Plant Biotechnology
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    • v.48 no.3
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    • pp.179-185
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    • 2021
  • Indoor gardening includes wall greening, terrariums, and flower arrangements. Among these types of indoor gardens, the terrarium is easy to access for the general public, but in Korea, because of the focus on esthetics, the original purpose of creating terrariums, which was to grow plants sustainably in an enclosed space, has been lost. In addition, miniaturization of plants is required to grow plants in an enclosed space. Since the available plant species suitable for a terrarium are limited, only plants such as succulents, cacti, and moss have been used. In this study, Bronze (X Graptosedum) was used, and these problems were solved using the following three methods: placement and growth of virus-free plants in the terrarium; extending the diversity of plants with minimal size that can be planted in terrariums; and reducing the price of in vitro plants with minimal size by achieving large-scale production. In particular, tissue-cultured succulents were developed into a Vivorium by replacing the tissue culture container and renewing the composition of the plant. This paper suggests a new indoor horticultural field, Vivorium, that can improve the current limitations of terrariums and make them more accessible to the general public. The introduction and popularization of new indoor gardening fields with the increase in single-person households and indoor activities in the Pandemic era can also improve psychological stability among people and in the society.

Distribution Prediction of Korean Clawed Salamander (Onychodactylus koreanus) according to the Climate Change (기후변화에 따른 한국꼬리치레도롱뇽(Onychodactylus koreanus)의 분포 예측에 대한 연구)

  • Lee, Su-Yeon;Choi, Seo-yun;Bae, Yang-Seop;Suh, Jae-Hwa;Jang, Hoan-Jin;Do, Min-Seock
    • Korean Journal of Environment and Ecology
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    • v.35 no.5
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    • pp.480-489
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    • 2021
  • Climate change poses great threats to wildlife populations by decreasing their number and destroying their habitats, jeopardizing biodiversity conservation. Asiatic salamander (Hynobiidae) species are particularly vulnerable to climate change due to their small home range and limited dispersal ability. Thus, this study used one salamander species, the Korean clawed salamander (Onychodactylus koreanus), as a model species and examined their habitat characteristics and current distribution in South Korea to predict its spatial distribution under climate change. As a result, we found that altitude was the most important environmental factor for their spatial distribution and that they showed a dense distribution in high-altitude forest regions such as Gangwon and Gyeongsanbuk provinces. The spatial distribution range and habitat characteristics predicted in the species distribution models were sufficiently in accordance with previous studies on the species. By modeling their distribution changes under two different climate change scenarios, we predicted that the distribution range of the Korean clawed salamander population would decrease by 62.96% under the RCP4.5 scenario and by 98.52% under the RCP8.5 scenario, indicating a sharp reduction due to climate change. The model's AUC value was the highest in the present (0.837), followed by RCP4.5 (0.832) and RCP8.5 (0.807). Our study provides a basic reference for implementing conservation plans for amphibians under climate change. Additional research using various analysis techniques reflecting habitat characteristics and minute habitat factors for the whole life cycle of Korean-tailed salamanders help identify major environmental factors that affect species reduction.

A Study on the Characteristics of Projects Following the Promotion of Private Park Special Projects (민간공원특례사업의 추진에 따른 사업특성에 관한 연구)

  • Gweon, Young-Dal;Park, Hyun-Bin;Kim, Dong-Pil
    • Journal of the Korean Institute of Landscape Architecture
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    • v.49 no.5
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    • pp.112-124
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    • 2021
  • This study was conducted to examine and analyze local governments, park status, project characteristics, and the implementation in detail for private park special projects across the country as a means of responding to the sunsetting of urban parks. As a result of the analysis, first, the private park special project, was found to be mainly implemented in cities with a population of more than 100,000, so there was a limit to the application on military installations or in local small cities. Therefore, rather than applying the special system collectively, it was judged that institutional flexibility, considering the characteristics and size of local government, was needed. Second, the current special projects by the park creation donation collection method shows monotonous development centered on apartment houses, so it is necessary to diversify the development by introducing a park preservation method that purchases and donates park sites. Third, it was found that the area standard needs to be eased to less than 50,000m2 to include parks with high utilization and good accessibility in urban areas of large cities, as the type and area of parks are limited. Fourth, most special projects are mountain parks, which are feared to damage the natural terrain and skyline, so separate ordinances should be established and applied, and development approaches should be made to allow nature and parks to coexist with the setting of detailed building guidelines for each type of facility. The guidelines should include, first, after the nationwide private park special projects are completed, standards for appropriate returns for similar projects should be established, institutional standards such as the recovery of excess profits should be established, and environmental reviews should be conducted. Second, it was found that local governments should institutionalize the composition of private consultations to promote the efficient management of projects through a cooperative system, and third, a roadmap for maintenance after the donation of special parks should be established.

The Current Status and Prospect of Presidential Records Management (대통령기록관리의 현황과 전망)

  • Zoh, Young-Sam
    • The Korean Journal of Archival Studies
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    • no.21
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    • pp.283-322
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    • 2009
  • Legislation and enforcement of the Presidential Records Management Law was an important turning point in Korean archival management history. In the past, the notion of presidential records was vague. The law was a starting point of establishing presidential records management. The Presidential Records Management Law provides the definition of presidential records and its scope, and establishes the protection of presidential records through restricted access to the records. The key to the law is to enable a president freely to produce records and transfer them to the next administration without omission. In other words, it aims to stop the practice that presidential records are produced but never be left. But, 'disputes over the release of presidential records' and the disclosing of access-restricted presidential records presented a crisis to national records management as well as the prospect of presidential records management, even if they were 'legal procedures.' The instability of presidential records management could give a serious impact on the national records management and its operation. Amid this situation, it is required to review the presidential records management system and provide recommendations for improvement, even if the enforcement of law has just started. The most urgent things in improving presidential records management are to secure its independence, specialty, and to complement restricted access to presidential records. For securing independency, presidential records management should be done by a separate organization other than the National Archives of Korea while for promoting specialty, a newly established organization could serve as a professional archive. And for complementing restricted access to the presidential records, the access should be more limited. In other words, more discretion is needed in permitting access. And more specific regulations should be applied to the permitted records. However, these regulatory actions may not have effects unless independency is not secured. Thus, more fundamentally, independency of the National Archives of Korea should be first established.

Clinical Evaluation of Guided Bone Regeneration Using 3D-titanium Membrane and Advanced Platelet-Rich Fibrin on the Maxillary Anterior Area (상악 전치부 3D-티타늄 차폐막과 혈소판농축섬유소를 적용한 골유도재생술의 임상적 평가)

  • Lee, Na-Yeon;Goh, Mi-Seon;Jung, Yang-Hun;Lee, Jung-Jin;Seo, Jae-Min;Yun, Jeong-Ho
    • Implantology
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    • v.22 no.4
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    • pp.242-254
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    • 2018
  • The aim of the current study was to evaluate the results of horizontal guided bone regeneration (GBR) with xenograf t (deproteinized bovine bone mineral, DBBM), allograf t (irradiated allogenic cancellous bone and marrow), titanium membrane, resorbable collagen membrane, and advanced platelet-rich fibrin (A-PRF) in the anterior maxilla. The titanium membrane was used in this study has a three-dimensional (3D) shape that can cover ridge defects. Case 1. A 32-year-old female patient presented with discomfort due to mobility and pus discharge on tooth #11. Three months after extracting tooth #11, diagnostic software (R2 GATE diagnostic software, Megagen, Daegu, Korea) was used to establish the treatment plan for implant placement. At the first stage of implant surgery, GBR for horizontal augmentation was performed with DBBM ($Bio-Oss^{(R)}$, Geistlich, Wolhusen, Switzerland), irradiated allogenic cancellous bone and marrow (ICB $cancellous^{(R)}$, Rocky Mountain Tissue Bank, Denver, USA), 3D-titanium membrane ($i-Gen^{(R)}$, Megagen, Daegu, Korea), resorbable collagen membrane (Collagen $membrane^{(R)}$, Genoss, Suwon, Korea), and A-PRF because there was approximately 4 mm labial dehiscence after implant placement. Five months after placing the implant, the second stage of implant surgery was performed, and healing abutment was connected after removal of the 3D-titanium membrane. Five months after the second stage of implant surgery was done, the final prosthesis was then delivered. Case 2. A 35-year-old female patient presented with discomfort due to pain and mobility of implant #21. Removal of implant #21 fixture was planned simultaneously with placement of the new implant fixture. At the first stage of implant surgery, GBR for horizontal augmentation was performed with DBBM ($Bio-Oss^{(R)}$), irradiated allogenic cancellous bone and marrow (ICB $cancellous^{(R)}$), 3D-titanium membrane ($i-Gen^{(R)}$), resorbable collagen membrane (Ossix $plus^{(R)}$, Datum, Telrad, Israel), and A-PRF because there was approximately 7 mm labial dehiscence after implant placement. At the second stage of implant surgery six months after implant placement, healing abutment was connected after removing the 3D-titanium membrane. Nine months after the second stage of implant surgery was done, the final prosthesis was then delivered. In these two clinical cases, wound healing of the operation sites was uneventful. All implants were clinically stable without inflammation or additional bone loss, and there was no discomfort to the patient. With the non-resorbable titanium membrane, the ability of bone formation in the space was stably maintained in three dimensions, and A-PRF might influence soft tissue healing. This limited study suggests that aesthetic results can be achieved with GBR using 3D-titanium membrane and A-PRF in the anterior maxilla. However, long-term follow-up evaluation should be performed.

The Effect Analysis of Vegetation Diversity on Rice-Fish Mixed Farming System in Paddy Wetland (벼-담수어 복합생태농업이 논습지 식생다양성에 미치는 영향 분석)

  • Kong, Minjae;Kim, Changhyun;Lee, Sangmin;Park, Kwanglai;An, Nanhee;Cho, Junglai;Kim, Bongrae;Lim, Jongahk;Lee, Changwon;Kim, Hyeongsu;Nam, Hongsik;Son, Jinkwan
    • Journal of Wetlands Research
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    • v.20 no.4
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    • pp.398-409
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    • 2018
  • Organic farming practices including loach based ecosystem-farming have been demonstrated to be effective in conjunction with rice farming to increase yield and quality. This new form of farming combines agriculture and fishery and is quickly developing into a new industry. The current study investigated the effect of rice-fish mixed farming system on the vegetation-diversity function. Vegetation within the four study sites was surveyed and analyzed based on plant taxonomy. The vegetation survey demonstrated that 127 taxa of 38 families, 100 genera, 107 species, and 20 varieties occurred within the study sites. A total of 15 plant species taxa occurred in the rice-fish mixed paddy fields with a fish habitat and did not occur in the conventional paddy field lacking fish habitat. This difference is thought to arise from differences in moisture requirements for vegetation. Life form analysis demonstrated differences in hemicryptophytes, therophytes, and hydrophytes according to fish habitat. The naturalized plants identified were also determined to be species widely distributed throughout Korea. Frequency analysis demonstrated that the rice-fish mixed paddy fields with a fish habitat had a high ratio of both obligate and facultative wetland plants relative to the conventional paddy field. Based on the study results, it is likely that vegetation-diversity will increase with environment diversity. However, no statistical significance was observed according to paddy types. Future research should aim to identify additional environmental factors, including the existence of fish habitat, habitat area, depth of fish habitat, hydrological parameters, water quality, and paddy soil environment, to enhance vegetation-diversity and biocultural diversity.

Composting Method and Physicochemical Characteristics of By-products from Home Garden Plants and Small Herbivore Feces (옥수수 부산물과 토끼 분변의 이화학적 성분특성 및 퇴비 제조조건)

  • Kim, Dae-Gyun;Kim, Jin-Young;Lee, Won-Suk;Kim, Hye-Hyeong;Seo, Myung-Whoon;Park, In-Tae;Hyun, Junge;Yoo, Gayoung
    • Journal of Environmental Impact Assessment
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    • v.27 no.6
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    • pp.695-703
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    • 2018
  • This study was conducted to suggest a sustainable farming practice forresource recycling in vegetable gardens of North Korea. In North Korea, farmers are allowed to own private vegetable gardens less than $100m^2$. However, usage of fertilizers in private vegetable gardens is very limited due to economic sanctions by UN security council. If North and South Korea initiated the cooperative action in the near future, agricultural sector would be the highest priority cooperation area. Considering the current North Korean situation in agriculture, we would like to suggest a method for producing organic fertilizer manure. For raw materials for producing manure, we selected corn byproduct, which is the most abundant material, and rabbits' feces, which are easily obtained from individual private farms in North Korea. As we cannot get corn byproducts and rabbits' feces from North Korea, we prepared samples of corn byproducts and rabbits; feces from many places in South Korea. After statistical analysis of variance, there was no significant difference in the T-N contents of corn byproducts from Gyeonggi, Gangwon, Chungnam, Chungbuk, Jeollabuk and Gyeongsangnam-dos, which indicates that the fertilizing quality of corn byproducts does not vary significantly in the spatial scale of South. Korea. In this sense, if we use corn samples from Gyeonggi province, they would not be very different from those of North Korean regions. Physicochemical properties of rabbits' feces were different between those eating feed grains and those eating plants only. Hence, we used rabbits' feces of the rabbits from Yeonchun area, which were fed by plants only. Using three different mixing ratios of corn byproducts and rabbits' feces, composting was conducted for 60 days. The mixing ratio of 1:1 produced the manure with % T-N of 1.98% and OM/N ratio of 31.7 after 30 days of composting, which is comparable to the quality of commercial manure.

A study on detective story authors' style differentiation and style structure based on Text Mining (텍스트 마이닝 기법을 활용한 고전 추리 소설 작가 간 문체적 차이와 문체 구조에 대한 연구)

  • Moon, Seok Hyung;Kang, Juyoung
    • Journal of Intelligence and Information Systems
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    • v.25 no.3
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    • pp.89-115
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    • 2019
  • This study was conducted to present the stylistic differences between Arthur Conan Doyle and Agatha Christie, famous as writers of classical mystery novels, through data analysis, and further to present the analytical methodology of the study of style based on text mining. The reason why we chose mystery novels for our research is because the unique devices that exist in classical mystery novels have strong stylistic characteristics, and furthermore, by choosing Arthur Conan Doyle and Agatha Christie, who are also famous to the general reader, as subjects of analysis, so that people who are unfamiliar with the research can be familiar with them. The primary objective of this study is to identify how the differences exist within the text and to interpret the effects of these differences on the reader. Accordingly, in addition to events and characters, which are key elements of mystery novels, the writer's grammatical style of writing was defined in style and attempted to analyze it. Two series and four books were selected by each writer, and the text was divided into sentences to secure data. After measuring and granting the emotional score according to each sentence, the emotions of the page progress were visualized as a graph, and the trend of the event progress in the novel was identified under eight themes by applying Topic modeling according to the page. By organizing co-occurrence matrices and performing network analysis, we were able to visually see changes in relationships between people as events progressed. In addition, the entire sentence was divided into a grammatical system based on a total of six types of writing style to identify differences between writers and between works. This enabled us to identify not only the general grammatical writing style of the author, but also the inherent stylistic characteristics in their unconsciousness, and to interpret the effects of these characteristics on the reader. This series of research processes can help to understand the context of the entire text based on a defined understanding of the style, and furthermore, by integrating previously individually conducted stylistic studies. This prior understanding can also contribute to discovering and clarifying the existence of text in unstructured data, including online text. This could help enable more accurate recognition of emotions and delivery of commands on an interactive artificial intelligence platform that currently converts voice into natural language. In the face of increasing attempts to analyze online texts, including New Media, in many ways and discover social phenomena and managerial values, it is expected to contribute to more meaningful online text analysis and semantic interpretation through the links to these studies. However, the fact that the analysis data used in this study are two or four books by author can be considered as a limitation in that the data analysis was not attempted in sufficient quantities. The application of the writing characteristics applied to the Korean text even though it was an English text also could be limitation. The more diverse stylistic characteristics were limited to six, and the less likely interpretation was also considered as a limitation. In addition, it is also regrettable that the research was conducted by analyzing classical mystery novels rather than text that is commonly used today, and that various classical mystery novel writers were not compared. Subsequent research will attempt to increase the diversity of interpretations by taking into account a wider variety of grammatical systems and stylistic structures and will also be applied to the current frequently used online text analysis to assess the potential for interpretation. It is expected that this will enable the interpretation and definition of the specific structure of the style and that various usability can be considered.

A Study on Management Present and Improvements of National Records Designation System (국가지정기록물 관리현황과 개선방안 연구)

  • Choi, Jae-Ho;Lee, Young-Hak
    • The Korean Journal of Archival Studies
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    • no.47
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    • pp.51-93
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    • 2016
  • This study is on management present and improvements on National Records Designation System. National Records Designation System is a system that supports management and preservation of changes of records designated by the government through consideration that such records are worth preserving permanently nationally among records acquired by individual or organization. This system is meaningful in a way that it established systematic foundation to hand down by informatizing historic private records which are in danger to be lost or damaged due to lack of proper care. However, compared to the number of designated records, the information that could be practically drawn from such records are limited. This triggered this study to be launched. National Archive sometimes promotes designation and management of National Designated records. Yet archival information service offering access of user to national designated records are very rare. I conducted survey and interview of managers, field research, and documentary research of 10 records holding institution that keeps national designated records currently. I considered that current management status of National Records Designation System can be figured out minutely through these research. As a result of such research, most of the records holding institutions offered display as their least archival information service. The objective of records informatization was to utilize the records. Also further plans on information service related to records and various utilization were suggested. records holding institution manager did not give positive answer on effect of designating national designated records and cooperation between National Archive. Support to National Archive only focused on preservation. For national designated records holding institution designated after 2011 were not getting proper support. In addition, National Archive's support rarely met records holding institution's need. In such circumstances, things to consider for improvements of National Records Designation System is as following. First, designation of national designated records should be based on the utilization of the record. Each records holding institution's willingness to utilize corresponding records and National Archive's ability to draw the willingness out should be considered. Also, it shouldn't be left as mere complementary policy of National Archive's selecting policy. Second, for National Records Designation System to be managed permanently, it should be changed as the system that supports enhancement of private records management. The aim should point to the direction where private can manage and preserve the records on their own. Third, There needs to be changes on the subject and process of national designated records designation. National designated record is the record that was considered valuable by the government among private records. Thus, such records should be the best one to show private field. Accordingly, records that represent contemporary society and include various states and contents should be chosen to be designated. Moreover, public discussion be formed by citizens and related professionals in order to properly select the record.