• Title/Summary/Keyword: 방향특성

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A Literature Review of Fish Feeding Research in the Coast - Estuary Areas of Korean Peninsula (우리나라 연안-하구에 서식하는 어류의 식성 관련 연구 현황)

  • Jo, Hyunbin;Kim, Dong-Kyun;Park, Kiyun;Lee, Wan-Ok;Kwak, Ihn-Sil
    • Korean Journal of Ecology and Environment
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    • v.52 no.2
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    • pp.126-135
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    • 2019
  • We carried out a literature review of fish food sources research in the coast - estuary areas of Korean peninsula for the last fifty years(1969~2018). A total of 101 research papers were reviewed, of which 81 were published in domestic journals, 7 were puliched in domestic reports and 14 were published in international journals. When divided into the decade periods, 21 papers (19.4%) between 1990 and 1999 and 26 papers (24.1%) between 2000 and 2009, and 42 papers (48.1%) were published in 2010 and 2018, respectively. When divided into the survey area by a bearing (East sea, South-East sea, South Sea, and West Sea), 65 papers(69.1%) were carried out in the South Sea. Followed by 13 papers (13.8%) in the East Sea and 8 papers (8.5%) in the West Sea and the South-East Sea, respectively. The surveyed area was dominant in Gwangyang Bay (18 papers; 24.3%), followed by Gadeok-do (8 papers; 10.8%). Of the diversity indices, 14 indices were used to calculate the ecological status. The dominant indices were IRI(Index of relative importance), Pi(Prey-specific abundance) followed by E (electivity index) and Bi (dietary breadth index). A total of 11 statistical methods were used to find feeding strategy. The correlation analysis and Bray-Curtis similarity matrix were applied most frequently. In terms of ecological research topics, the papers focused on seasonal or spatial differences before 2000. Since 2000, specifically, the international journal papers have been published based on competition, sympatric, niche overlap and other ecological topics.

Current Status and Future Development Direction of University Archives' Information Services : Based on the Interview with the Archives' Staff (대학기록관 기록정보서비스의 현황과 발전 방안 실무자 면담을 중심으로)

  • Lee, Hye Kyoung;Rieh, Hae-Young
    • The Korean Journal of Archival Studies
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    • no.40
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    • pp.131-180
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    • 2014
  • Various theoretical studies have been conducted to activate university archives, but the services provided currently in the field haven't been much studied. This study aims to investigate the usage and users of the domestic university archives, examine the types of the archival information services provided, understand the characteristics and limitations of the services, and suggest the development direction. This study set 3 objectives for the research. First, Identify the users of the university archives, the reason of the use, and the kinds of archival materials used. Second, the kinds of services and programs the university archives provide to the users. Third, the difficulties the university archives face to execute information services, the plans they consider in the future, and the best possible direction to prove the services. The authors of the study determined to apply interviews with the staffs at university archives to identify the current status of the services. For this, the range of the services offered in the field of university archives was defined first, and then, key research questions were composed. To collect valid data, authors carried out face to face interviews and email/phone interviews with the staff of 12 university archives, as well as the investigation of their Web sites. The collected data were categorized by the topic of the interview questions for analysis. By analyzing the data, some useful information was yielded including the demographic information of the research participants, the characteristics of the archives' users and requests, the types and activities of the services the university archives offered, and the limitations of archival information services, the archives' future plans, and the best possible development direction. Based on the findings, this study proposed the implications and suggestions for archival information services in university archives, in 3 domains as follows. First, university archives should build close relationship with internal university administrative units, student groups, and faculty members for effective collection and better use of archives. Second, university archives need to acquire both administrative records by transfer and manuscripts and archives by active collection. Especially, archives need to try to acquire unique archives of the universities own. Third, the archives should develop and provide various services that can elevate the awareness of university archives and induce more potential users to the archives. Finally, to solve the problems the archives face, such as the lack of the understanding of the value of the archives and the shortage of the archival materials, it was suggested that the archivists need to actively collect archival materials, and provide the valuable information by active seeking in the archives where ever it is needed.

Changes of Spatial Distribution of Korean Red Pine Forest in Hallasan National Park (한라산국립공원 소나무림의 공간분포 변화)

  • Kim, Jong-Kab;Koh, Jung-Goon;Yim, Hyeong-Taek;Kim, Dong-Soon
    • Korean Journal of Environment and Ecology
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    • v.33 no.5
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    • pp.578-586
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    • 2019
  • The purpose of this study was to investigate the change of spatial distribution of Korean red pine (Pinus densiflora Siebold & Zucc.) in Hallasan National Park by surveying the distribution and crown density and analyzing by the elevation, slope, orientation, and regional habitat in 2006 and 2015. The total area of the Korean red pine forest was 1,259.9 ha in 2015, which increased by 51.4 ha, or 4.1%, compared to 1,208.5 ha in 2006. For the past 10 years, the area of sparse density with crown density of 11% to 40% of Korean red pine increased by 59.8 ha, the area of moderate density with crown density of 41% to 70% increased by 59.0 ha, and the area of dense density with 71% or more crown density increased by 67.3 ha. In terms of the altitude above sea level, the Korean red pine forest area between 1,010 m and 1,400 m was the largest at 1,003.0 ha or 79.6% of the total area in 2015. The area between 1,100 m and 1,300 m increased, and the area of dense density decreased significantly while the areas of moderate density and sparse density increase. There was no notable change according to the land slope, and the area increased from 2006 regardless of the slope. By direction, 56.4% were distributed in the southwest and southeast directions centered on the south-facing slope with the increase of 27.8 ha over the 10 years while the northwest and northeast directions centered on the north-facing slope decreased by 7.6 ha. Regarding the distribution change of the Korean red pine forest by the region, the Yeongsil area showed an increase of 25.5 ha, or 49.6% of the total area increase, in 2006 while the Ibseog-oreum area including the right side on the Sanbeoleum mountain valley increased by 20.4 ha. The distribution in the Gaemideung area that includes Jogeundeule increased by 7.4 ha while that of Sogbat in Sungpanak Trail decreased by 1.9 ha. This study analyzed the changes in the distribution area and crown density of the Korean red pine forest according to the altitude, slope, direction, and regional habitat in Hallasan National Park. The expansion of Korean red pine forest distribution was limited to the areas where the grass and the shrub was the dominating vegetation structure, or the forest gap was created by the disturbance. On the other hand, the distribution area of the Korean red pine forest surrounded by deciduous broad-leaved forests or mixed vegetation structure is considered to result from the change in density more than the area due to competition with deciduous broad-leaved trees.

An Experimental Study on the Hydration Heat of Concrete Using Phosphate based Inorganic Salt (인산계 무기염을 이용한 콘크리트의 수화 발열 특성에 관한 실험적 연구)

  • Jeong, Seok-Man;Kim, Se-Hwan;Yang, Wan-Hee;Kim, Young-Sun;Ki, Jun-Do;Lee, Gun-Cheol
    • Journal of the Korea Institute of Building Construction
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    • v.20 no.6
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    • pp.489-495
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    • 2020
  • Whereas the control of the hydration heat in mass concrete has been important as the concrete structures enlarge, many conventional strategies show some limitations in their effectiveness and practicality. Therefore, In this study, as a solution of controling the heat of hydration of mass concrete, a method to reduce the heat of hydration by controlling the hardening of cement was examined. The reduction of the hydration heat by the developed Phosphate Inorganic Salt was basically verified in the insulated boxes filled with binder paste or concrete mixture. That is, the effects of the Phosphate Inorganic Salt on the hydration heat, flow or slump, and compressive strength were analyzed in binary and ternary blended cement which is generally used for low heat. As a result, the internal maximum temperature rise induced by the hydration heat was decreased by 9.5~10.6% and 10.1~11.7% for binder paste and concrete mixed with the Phosphate Inorganic Salt, respectively. Besides, the delay of the time corresponding to the peak temperature was apparently observed, which is beneficial to the emission of the internal hydration heat in real structures. The Phosphate Inorganic Salt that was developed and verified by a series of the aforementioned experiments showed better performance than the existing ones in terms of the control of the hydration heat and other performance. It can be used for the purpose of hydration heat of mass concrete in the future.

A History of Termite Control and Improvements to Prevent Termites in Wooden Architectural Heritage (국내외 흰개미 방제 기술의 발달 과정과 목조건축문화재의 흰개미 피해 저감을 위한 방안)

  • LEE, Sangbin;IM, Ikgyun;KIM, Sihyun
    • Korean Journal of Heritage: History & Science
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    • v.54 no.2
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    • pp.194-215
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    • 2021
  • Termites are important decomposers in the ecosystem. They are also economically significant structural pests. In this study, we reviewed the developments of termite control and recent research on termite management to provide information on the prevention and control of termites. In Korea, most of the damage to wooden historical buildings is caused by subterranean termites. Reticulitermes speratus kyushuensis is the main species, which is widely found throughout the country. In the early 1900s, inorganic insecticides, such as arsenic dust, were used for termite control. After the synthesis of chlorinated hydrocarbon pesticide in the 1940s, it was widely utilized and demonstrated high termite control efficacy. However, chlorinated hydrocarbon insecticides were later banned, disappearing from markets after reports emerged concerning environmental contamination and toxicity to humans. Therefore, the termite control industry sought a new termiticide; hence many pesticides were utilized for termite control. Organophosphate (1960s), carbamate (1970s), pyrethroid, and insect growth inhibitor (1980s) were newly synthesized and adopted. In the 1990s, the first commercial baits using chitin synthesis inhibitors (CSI) were developed, providing a means to eliminate an entire colony of subterranean termites around a structure. Many studies have been carried out on soil termiticides (liquid termiticides) and CSI baits to increase their efficacy, and different baits such as aboveground bait stations, fluid bait, and high-durability bait were also developed in the 2000s. In addition, the paradigm of termite control has shifted from localized treatments using soil termiticides to area-wide pest management using CSI baits to create termite-free zones and protect buildings over time. Termite infestations in wooden historical buildings in Korea have been reported since 1980, and considerable attention was drawn in the 1990s when several UNESCO world heritages such as the Jongmyo Shrine and the Janggyeong Panjeon Depositories of Haeinsa Temple were infested by subterranean termites. Since then, a survey of termite infestation in wooden architectural heritage has been conducted, and the National Research Institute of Cultural Heritage and Heritage Care Program regularly monitors those properties. Finally, we suggest termite management using primarily CSI baits, selective application of various soil treatments applied to the object, foundation soil treatment, research and development of durable termite baits, application of area-wide programs for wooden-building complexes, application of integrated termite management (ITM), and regular education for owners and managers to prevent and reduce termite damage.

Cytotoxic Effect and Protein Expression by Korean Regional Propolis on HeLa Ovarian Cancer Cell Line (HeLa 암세포주에 대한 국산 프로폴리스의 독성 효과 및 단백질 발현 변화)

  • Kim, Sung-Kuk;Woo, Soon Ok;Han, Sang Mi;Kim, Se Gun;Bang, Kyung Won;Kim, Hyo Young;Choi, Hong Min;Moon, Hyo Jung
    • Journal of Apiculture
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    • v.34 no.3
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    • pp.245-254
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    • 2019
  • We investigated the anti-tumor effects and molecular mechanism of Brazil, China and Korean regional propolis on HeLa ovarian cancer cell line. Each propolis extracts was prepared by ethanol extraction method. Cytotoxicity of propolis extracts was determinated by EZ-cytox cell viability assay. To necessity of anti-tumor effect and molecular mechanism of propolis, we must be adjusting propolis concentration. Due to 100 ㎍/mL of propolis extract were reduced cell viability to less than 50%, we adjusted all of propolis concentration to 100 ㎍/mL. By Western blotting analysis, we confirmed that anti-tumor mechanism of Brazil, China and Korea regional propolis has significantly difference. All of propolis was activated apoptosis related molecules such as PARP, caspase-3. However, cell proliferation signaling molecules including Akt1, ERK and Bcl-2 were reduced the protein expression level. Especially, the expression of tumor suppressor protein p53 was significantly increased in propolis-treated group such as Gyeonggi, Chungbuk, Chungnam, Jeonbuk, Gyeongnam and China. The phosphorylation of Bax which as apoptosis indicator was appeared in propolis-treated group such as Gyeonggi, Gangwon, Chungnam, Gyeongbuk, China. In this results showed that the regional propolis has completely different mechanism in anti-tumor. Thus, propolis extracts may be useful source of functional materials on anti-cancer and it will be able to choose the suitable propolis for cancer therapy by analyzing individual characteristics.

A Study on the trend of change in the number of elementary school students in Korea (우리나라 초등학교 학생수 변화 패턴에 대한 조사 연구)

  • Yoon, Yong-Gi;Choi, Ki-Seok
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.20 no.2
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    • pp.1-10
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    • 2021
  • The results of research and analysis are as follows: First, there were 108 types of change patterns in the number of elementary school students. Second, based on the similarity of 108 types of change patterns in the number of students, a type system diagram was presented. Third, in the case of a total of 18 types of change patterns in the number of students, the number of students decreased significantly due to the establishment of additional schools on top of the existing schools. The result of a a long-term survey and analysis on the trend of increase and decrease in the number of students across the country shows an urgent need todevelop policy tasks across the entire school accommodation plan, such as the establishment of differentiated schools suitable for regional characteristics, relocation, consolidation, reorganization of school districts, remodeling, and appropriatization projects.

A Study Covering the Comparative Analysis of Educational Systems in Major Countries for Regular Cybersecurity Education (사이버보안 정규교육화를 위한 주요국 교육체계 비교분석 연구)

  • YOO, Jiyeon
    • The Journal of the Convergence on Culture Technology
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    • v.7 no.1
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    • pp.397-405
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    • 2021
  • With the recent phenomenon of the Intelligence Information Society, the cyber security paradigm has begun to change. In particular, the increase of the interconnectedness of the hyperlinked society has extended the scope of damage that can be caused by cyber threats to the real world. In addition to that, it can also be a risk to any given individual who could accompany a crisis that has to do with public safety or national security. Adolescents who are digital natives are more likely to be exposed to cyber threats, which is mainly due to the fact that they are significantly more involved in cyber activities and they also possess insufficient security comprehension and safety awareness. Therefore, it is necessary to strengthen cyber security capabilities of every young individual, so that they can effectively protect themselves against cyber threats and better manage their cyber activities. It examines the changes of the security paradigm and the necessity for cyber security education, which is in direct accordance to the characteristics of a connected society that further suggests directions and a basic system of cyber security education, through a detailed analysis of the current state of Domestic and Overseas Cyber Security Education. The purpose of this study was to define cybersecurity competencies that are necessary within an intelligent information society, and to propose a regular curriculum for strengthening cybersecurity competencies, through the comparison and meticulous analysis of both domestic and overseas educational systems that are pertinent to cybersecurity competencies. Accordingly, a cybersecurity competency system was constructed, by reflecting C3-Matrix, which is a cyber competency system model of digital citizens. The cybersecurity competency system consists of cyber ethics awareness, cyber ethics behavior, cyber security and cyber safety. In addition to this, based on the basic framework of the cybersecurity competency system, the relevant education that is currently being implemented in the United States, Australia, Japan and Korea were all compared and analyzed. From the insight gained through the analysis, the domestic curriculum was finally presented. The main objective of this new unified understanding, was to create a comprehensive and effective cyber security competency curriculum.

Health and nutrition intake status of the Korean elderly according to their food security level: data from the 7th Korea National Health and Nutrition Examination Survey (KNHANES VII), 2016-2018 (식품안정성 수준에 따른 한국노인의 건강상태와 영양섭취현황: 제7기 (2016-2018) 국민건강영양조사 자료 활용)

  • Maeng, Ahreum;Lee, Jeehyun;Yoon, Eunju
    • Journal of Nutrition and Health
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    • v.54 no.2
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    • pp.179-198
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    • 2021
  • Purpose: This study examined general characteristics, health status, accessibility to medical services, health-related quality of life, dietary behavior, and energy and nutrient intakes of the elderly at different levels of food security utilizing data from the 7th Korea National Health and Nutrition Examination Survey (2016-2018). Methods: The elderly subjects (1,721 males and 2,271 females) were divided into 3 groups (secure, mildly insecure, moderately/severely insecure) according to their food security levels. Health and nutrient status was determined using energy intake, nutrient density, the prevalence of insufficient nutrient intake, dietary behavior, and health status. Results: The elderly with food insecurities had a lower self-evaluated health status and a higher prevalence of physician-diagnosed chronic diseases such as arthritis, osteoarthritis, rheumatoid arthritis, osteoporosis for males, and hypertension, stroke, arthritis, and osteoarthritis for females. The associated financial burden was the major reason for not accessing medical services in the food insecure group. Furthermore, the food insecure group had a higher risk of impaired health-related quality of life compared to the secure group. The proportion of subjects with an energy intake below the estimated energy requirement was higher in the food insecure group and a significantly higher prevalence of insufficient intake was observed for all the nutrients (proteins, vitamin A, vitamin B1, vitamin B2, niacin, vitamin C, calcium, and iron) assessed in this study compared to the food secure group. Conclusion: This study suggests that food insecurity poses a challenge to the health and nutritional status of the elderly population in Korea and needs proper management. It would be helpful to develop food and nutrition assistance programs to ensure the food stability of the elderly population and assure quality to address gaps in their nutrient intake.

The Influence of the Characteristics of Drainage Basin on Depositional Processes of the Alluvial Fan: An Example from the Cretaceous Duwon Formation in Goheung Area (유역분지 특성에 따른 충적선상지의 퇴적작용: 고흥군 백악기 두원층의 예)

  • Lee, Kyung Jin;Park, Seung-Ik;Lee, Hyojong;Gihm, Yong Sik
    • Economic and Environmental Geology
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    • v.54 no.4
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    • pp.441-456
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    • 2021
  • The Cretaceous Duwon Formation was studied on the basis of sedimentologic analysis in order to unravel geologic conditions for the development of the streamflow-dominated alluvial fan under arid to semi-arid climatic conditions. The Duwon Formation unconformably overlies the Paleoproterozoic gneiss (basement). Based on the sedimentologic analysis, the Duwon Formation is interpreted to have been deposited in gravelly braided stream (FA-1) near the basement, laterally transitional to sandy braided stream (FA-2) and floodplain environments (FA-3) with distance (< 7 km) from the basement. Lateral changes in sedimentary facies and the well development of calcrete nodules in FA-3, together with radial paleocurrent directions measured in FA-1, are suggestive of the deposition of the Duwon Formation in streamflow-dominated alluvial fan under arid to semi-arid climatic conditions. Recent analysis of detrital zircon chronology suggests that sediments of the Duwon Formation were derived from the southwestern part of the Korean peninsula, including the western part of Yeongnam Massif and the southwestern part of Okcheon Belt. This implies the alluvial fan where the Duwon Formation accumulated had the large drainage basin. Because the large drainage basin can supply the significant amounts of water and temporarily store the sediments within the basin, watery floodwater carried sediments to the alluvial fan rather than the debris flows. Furthermore, the drainage basin largely composed of coarse-grained metamorphic and igneous rocks produced sand-grade sediments, preventing evolution of floodwater into debris flows. We suggest that combined effects of the large drainage basin and its coarse-grained metamorphic and igneous rocks provided favorable conditions for the development of streamflow-dominated alluvial fan, despite arid to semi-arid climatic conditions during sedimentation.