• Title/Summary/Keyword: 구조화 강도

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Geophysical characteristics of seamounts around Dok Island (동해 독도주변 해산의 지구물리학적 특성)

  • 강무희;한현철;윤혜수;이치원
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.7 no.4
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    • pp.267-285
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    • 2002
  • Dok Island, a Pliocene volcano, lies in the southwestern part of the East Sea. Most the work to date have focused primarily on the petrolography of the island, and as a result, the morphological characteristics and internal structure of the volcanic edifices of the Dok Island remain poorly understood. To provide better constraints on these features, bathymetric data with multibeam echo sounder, 32-channel seismic and 3D gravity modeling were used in this study. Three positive topographic highs are present in the study area, and these highs satisfy the seamount criteria. They are named as Dokdo, Tamhae, and Donghae seamounts. 32-channel seismic survey was conducted to investigate the sediment thickness of the area, which shows that there are no sediments near the summit of seamounts. Away from the seamounts, however, sediment becomes thick(>2000 m) toward the western part of the study area, and sediments in the northern and southern parts are about 1000 m thick. Free-Air gravity anomalies in this study generally follow the bathymetric feature with less than -20 mGal at the western part, but increase towards the seamounts. In the summit of the Dokdo Seamount, anomalies reach over 120 mGal, and in Tamhae and Donghae seamounts, the peak anomaly shows 90 and 70 mGals, respectively. All seamounts have an isolated volcanic conduit in their centre and show regional compensation root with 0.5~1.5 km thickness. The flat-topped summit of the seamounts is probably caused by wave truncation, indicating the sea level at the time of formation of the flat-topped geometry. Comparison between the present-day sea level and subsidence level during the opening of the East Sea suggests that the seamounts in the study area have subsided by 200~300 m after the formation. Furthermore, it implies that the seamounts formed over 12~10 Ma.

Electrochemical Performance as the Positive Electrode of Polyaniline and Polypyrrole Hollow Sphere with Different Shell Thickness (껍질 두께가 다른 폴리아닐린과 폴리피롤 속 빈 구형체 양전극의 전기화학적 성능)

  • Yun, Su-Ryeon;Hwang, Seung-Gi;Cho, Sung-Woo;Kang, Yongku;Ryu, Kawng-Sun
    • Applied Chemistry for Engineering
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    • v.23 no.2
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    • pp.131-137
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    • 2012
  • Polyaniline (PANI) and polypyrrole (Ppy) hollow sphere structures with controlled shell thicknesses can be easily synthesized than those of using a layer-by-layer method for cathode active material of lithium-ion batteries. Polystyrene (PS) core was synthesized by emulsion polymerization using an anion surfactant. The shell thicknesses of PANI and Ppy were controlled by amounts of aniline and pyrrole monomers. PS was removed by an organic solution. This structure increased in contact with an electrolyte and a specific capacity in lithium-ion batteries. But polymers have disadvantages such as the difficult control of molecular weights and low densities. These disadvantages were completed by controlled shell thicknesses. The amount of aniline monomer increased from 1.2, 2.4, 3.6, 4.8 to 6.0 mL, and the shell thicknesses were 30.2, 38.0, 42.2, 48.2, and 52.4 nm, respectively. And the amount of pyrrole monomer was 0.6, 1.2, 2.4 and 3.6 mL, the shell thicknesses were 16.0, 22.0, 27.0 and 34.0 nm, respectively. In the cathode materials with controlled shell thicknesses, shell thicknesses of the PANI hollow spheres were 30.2, 42.2, and 52.4 nm, and discharge specific capacities of after 10 cycle were ~18, ~29, and ~62 mAh/g, respectively. The shell thicknesses of the Ppy hollow spheres were 16.0, 22.0, 27.0 and 34.0 nm, and discharge specific capacities of after 15 cycle were ~15, ~36, ~56, and ~77 mAh/g, respectively. Thus, shell thicknesses of PANI and Ppy increased, the specific capacities increased.

Analysis of Plants Social Network for Vegetation Management on Taejongdae in Busan Metropolitan City (부산 태종대 식생관리를 위한 식물사회네트워크 분석)

  • Sang-Cheol Lee;Hyun-Mi Kang;Seok-Gon Park;Jae-Bong Baek;Chan-Yeol Yu;In-Chun Hwang;Song-Hyun Choi
    • Korean Journal of Environment and Ecology
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    • v.36 no.6
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    • pp.651-661
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    • 2022
  • Plants social network analysis, which combines plants society and social network analyses, is a new research method for understanding plants society. This study was conducted to investigate the relationship between species, using plant social network analysis targeting Taejongdae in Busan, and build basic data for management. Taejongdae, located in the warm temperate forest in Korea, is a representative coastal forest of Busan Metropolitan City, and the Pinus thunbergii-Eurya japonicacommunity is widely distributed. This study set up 100 quadrats (size of 100m2each) in Taejongdae to investigate the species that emerged and analyzed the interspecies association focusing on major species. Based on the results, a sociogram was created using the Gephi 0.9.2, and the network centrality and structure were analyzed. The results showed that the frequency of appearance was high in the order of P. thunbergii, E. japonica, Quercus serrata, Sorbus alnifolia, Ligustrum japonicum, and Styrax japonicusand that many evergreen broad-leaved trees appeared due to the environmental characteristics of the site. The plants social network of Taejongdae was composed of a small-scale network with 50 nodes and 172 links and was divided into 4 groups through modularization. The succession sere identified through a sociogram confirmed that the group that include P. thunbergiiand E. japonicawould progress to a deciduous broadleaf community dominated by Q. serrataand Carpinus tschonoskii, using hub nodes such as Prunus serrulataf. spontaneaand Toxicodendron trichocarpum. Another succession sere was highly likely to progress to an evergreen broad-leaved community dominated by Machilus thunbergiiand Neolitsea sericea, using M. thunbergiias a medium. In some areas, a transition to a deciduous broad-leaved community dominated by Celtis sinensis, Q. variabilisand Zelkova serratausing Lindera obtusilobaand C. sinensisas hub nodes was expected.

A Basic Study on the Establishment of Preservation and Management for Natural Monument(No.374) Pyeongdae-ri Torreya nucifera forest of Jeju (천연기념물 제374호 제주 평대리 비자나무 숲의 보존·관리방향 설정을 위한 기초연구)

  • Lee, Won-Ho;Kim, Dong-Hyun;Kim, Jae-Ung;Oh, Hae-Sung;Choi, Byung-Ki;Lee, Jong-Sung
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.32 no.1
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    • pp.93-106
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    • 2014
  • In this study, Analyze environment of location, investigation into vegetation resources, survey management status and establish to classify the management area for Natural monument No.374 Pyengdae-ri Torreya nucifera forest. The results were as follows: First, Torreya nucifera forest is concerned about influence of development caused by utilization of land changes to agricultural region. Thus, establish to preservation management plan for preservation of prototypical and should be excluded development activity to cause the change of terrain that Gotjawal in the Torreya nucifera forest is factor of base for generating species diversity. Secondly, Torreya nucifera forest summarized as 402 taxa composed 91 familly 263 genus, 353 species, 41 varieties and 8 forms. The distribution of plants for the first grade & second grade appear of endangered plant to Ministry of Environment specify. But, critically endangered in forest by changes in habitat, diseases and illegal overcatching. Therefore, when establishing forest management plan should be considered for put priority on protection. Thirdly, Torreya nucifera representing the upper layer of the vegetation structure. But, old tree oriented management and conservation strategy result in poor age structure. Furthermore, desiccation of forest on artificial management and decline in Torreya nucifera habitat on ecological succession can indicate a problem in forest. Therefore, establish plan such as regulation of population density and sapling tree proliferation for sustainable characteristics of the Torreya nucifera forest. Fourth, Appear to damaged of trails caused by use. Especially, Scoria way occurs a lot of damaged and higher than the share ratio of each section. Therefore, share ratio reduction Plan should be considered through the additional development of tourism routes rather than the replacement of Scoria. Fifth, Representing high preference of the Torreya nucifera forest tourist factor confirmed the plant elements. It is sensitive to usage pressure. And requires continuous monitoring by characteristic of Non-permanent. In addition, need an additional plan such as additional development of tourism elements and active utilizing an element of high preference. Sixth, Strength of protected should be differently accordance with importance. First grade area have to maintenance of plant population and natural habitats. Set the direction of the management. Second grade areas focus on annual regeneration of the forest. Third grade area should be utilized demonstration forest or set to the area for proliferate sapling. Fourth grade areas require the introduced of partial rest system that disturbance are often found in proper vegetation. Fifth grade area appropriate to the service area for promoting tourism by utilizing natural resources in Torreya nucifera forest. Furthermore, installation of a buffer zone in relatively low ratings area and periodic monitoring to the improvement of edge effect that adjacent areas of different class.

Multiplication of Infectious Flacherie and Densonucleosis Viruses in the Silkworm, Bombyx mori (가잠의 전염성 연화병 및 농핵병 바이러스 증식에 관한 연구)

  • 김근영;강석권
    • Journal of Sericultural and Entomological Science
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    • v.25 no.2
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    • pp.1-31
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    • 1984
  • Flacherie, as one of the most prevalent silkworm diseases, causes severe economic damage to sericultural industry and its pathogens have been proved to be flacherie virus (FV) and densonucleosis virus (DNV). Multiplications of the viruses in the larvae of the silkworm, Bombyx mori, were studied by the sucrose density gradient centrifugation and electron microscopy. The quantitative and qualitative changes of nucleic acids and proteins were investigated from the midgut and hemolymph in the silkworm larvae infected separately with FV and DNV. The histopathological changes of epithelial cells of infected midgut also were examined by an electron microscope. 1. Purified fractions of FV or DNV in a sucrose density gradient centrifugation yielded one homogenous and sharp peak without a shoulder, suggesting no heterogenous materials in the preparation. Electron microscopy also revealed that FV and DNV were spherical particles, 27nm and 21nm in diameter, respectively. 2. Silkworm larvae showed a decrease in body weight on the 6th day and in midgut weight on the 3rd day after inoculation with FV or DNV. 3. DNA content was higher in the midgut when infected with FV or DNV, but the hemolymph of the infected larvae showed no difference during first 6 days after inoculation, after which DNA concentration declined rapidly. 4. RNA synthesis of silkworm larvae infected separately with FV and DNV was stimulated in the midgut, but RNA content was reduced in the hemolymph at the early stage of virus multiplication. At the late stage of virus multiplication, however, it was extremely reduced in both midgut and hemolymph. 5. The concentration of protein in the midgut and hemolymph of silkworm larvae infected separately with FV and DNV showed no difference from that of the healthy larvae at the early stage of virus multiplication, but it was significantly reduced at the late stage of virus multiplication. 6. There was no difference in the electrophoretic patterns of RNAs extracted from the midgut of healthy or virus-infected larvae. 7. The electrophoresis of proteins extracted from the midgut infected with FV or DNV, when carried out on the 1st and 5th day after virus inoculation, showed no difference from that of the healthy larvae. But, there was an additional band with medium motility in the proteins on the 8th day after virus inoculation, while a band with low mobility shown in the proteins of healthy larvae disappeared in the infected larvae. However, a band with high mobility in the healthy larvae was separated into two fractions in the infected larvae. 8. The electrophoretic pattern of hemolymph proteins of the silkworm larvae infected separately with FV and DNV was similar to that of the healthy larvae, but the concentration of hemolymph proteins in the infected larvae was lower than that of the healthy larvae at the late stage. 9. Two types of inclusion bodies were shown by the double staining of pyronin-methyl green in the columnar cell of the midgut on the 8th day after FV inoculation. 10. Electron microscopy of the infected midgut revealed that the 'cytoplasmic wall' of the goblet cell thickened on the 5th day after FV inoculation and several types of the cytopathogenic structures, such as virus$.$specific vesicles, virus particles, linear structures, tubular structures, and high electron-dense matrices were observed in the cytoplasm of the goblet cell. The virus particles were also observed in the microvilli and the structures similar to spherical virus particles were observed around the virus-specific vesicles, suggesting the virus assembly in the cytoplasm. 11. Fluorescence micrograph of the infected midgut stained with acridine orange showed that the nucleus, the site of DNV multiplication in the columnar cell, enlarged on the 5th day after virus inoculation. 12. Electron microscopic examination of DNV infected midgut revealed that the nucleolus of the columnar cell was broken into granules and those granules dispersed into apical region of the nucleus on the 5th day after virus inoculation. On the 8th day after inoculation, it was also observed that the nucleus of the columnar cell was full with the high electron-dense virogenic stroma which were similar to virus particles. These facts suggest that the virogenic stroma were the sites of virus assembly in the process of DNV multiplication.

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MR T2 Map Technique: How to Assess Changes in Cartilage of Patients with Osteoarthritis of the Knee (MR T2 Map 기법을 이용한 슬관절염 환자의 연골 변화 평가)

  • Cho, Jae-Hwan;Park, Cheol-Soo;Lee, Sun-Yeob;Kim, Bo-Hui
    • Progress in Medical Physics
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    • v.20 no.4
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    • pp.298-307
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    • 2009
  • By using the MR T2 map technique, this study intends, first, to measure the change of T2 values of cartilage between healthy people and patients with osteoarthritis and, second, to assess the form and the damage of cartilage in the knee-joint, through which this study would consider the utility of the T2 map technique. Thirty healthy people were selected based on their clinical history and current status and another thirty patients with osteoarthritis of the knee who were screened by simple X-ray from November 2007 to December 2008 were selected. Their T2 Spin Echo (SE hereafter) images for the cartilage of the knee joint were collected by using the T2 SE sequence, one of the multi-echo methods (TR: 1,000 ms; TE values: 6.5, 13, 19.5, 26, 32.5. 40, 45.5, 52). Based on these images, the changes in the signal intensity (SI hereafter) for each section of the cartilage of the knee joint were measured, which yielded average values of T2 through the Origin 7.0 Professional (Northampton, MA 01060 USA). With these T2s, the independent samples T-test was performed by SPSS Window version 12.0 to run the quantitative analysis and to test the statistical significance between the healthy group and the patient group. Closely looking at T2 values for each anterior and lateral articular cartilage of the sagittal plane and the coronal plane, in the sagittal plane, the average T2 of the femoral cartilage in the patient group with arthritis of the knee ($42.22{\pm}2.91$) was higher than the average T2 of the healthy group ($36.26{\pm}5.01$). Also, the average T2 of the tibial cartilage in the patient group ($43.83{\pm}1.43$) was higher than the average T2 in the healthy group ($36.45{\pm}3.15$). In the case of the coronal plane, the average T2 of the medial femoral cartilage in the patient group ($45.65{\pm}7.10$) was higher than the healthy group ($36.49{\pm}8.41$) and so did the average T2 of the anterior tibial cartilage (i.e., $44.46{\pm}3.44$ for the patient group vs. $37.61{\pm}1.97$ for the healthy group). As for the lateral femoral cartilage in the coronal plane, the patient group displayed the higher T2 ($43.41{\pm}4.99$) than the healthy group did ($37.64{\pm}4.02$) and this tendency was similar in the lateral tibial cartilage (i.e., $43.78{\pm}8.08$ for the patient group vs. $36.62{\pm}7.81$ for the healthy group). Along with the morphological MR imaging technique previously used, the T2 map technique seems to help patients with cartilage problems, in particular, those with the arthritis of the knee for early diagnosis by quantitatively analyzing the structural and functional changes of the cartilage.

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Cooperation Strategy in the Business Ecosystem and Its Healthiness: Case of Win - Win Growth of Samsung Electronics and Partnering Companies (기업생태계 상생전략과 기업건강성효과: 삼성전자와 협력업체의 상생경영사례를 중심으로)

  • Sung, Changyong;Kim, Ki-Chan;In, Sungyong
    • The Journal of Small Business Innovation
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    • v.19 no.4
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    • pp.19-39
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    • 2016
  • With increasing adoption of smart products and complexity, companies have shifted their strategies from stand alone and competitive strategies to business ecosystem oriented and cooperative strategies. The win-win growth of business refers to corporate efforts undertaken by companies to pursue the healthiness of business between conglomerates and partnering companies such as suppliers for mutual prosperity and a long-term corporate soundness based on their business ecosystem and cooperative strategies. This study is designed to validate a theoretical proposition that the win-win growth strategy of Samsung Electronics and cooperative efforts among companies can create a healthy business ecosystem, based on results of case studies and surveys. In this study, a level of global market access of small and mid-sized companies is adopted as the key achievement index. The foreign market entry is considered as one of vulnerabilities in the ecosystem of small and mid-sized enterprises (SMEs). For SMEs, the global market access based on the research and development (R&D) has become the critical component in the process of transforming them into global small giants. The results of case studies and surveys are analyzed mainly based on a model of a virtuous cycle of Creativity, Opportunity, Productivity, and Proactivity (the COPP model) that features the characteristics of the healthiness of a business ecosystem. In the COPP model, a virtuous circle of profits made by the first three factors and Proactivity, which is the manifestation of entrepreneurship that proactively invests and reacts to the changing business environment of the future, enhances the healthiness of a given business ecosystem. With the application of the COPP model, this study finds major achievements of the win-win growth of Samsung Electronics as follows. First, Opportunity plays a role as a parameter in the relations of Creativity, Productivity, and creating profits. Namely, as companies export more (with more Opportunity), they are more likely to link their R&D efforts to Productivity and profitability. However, companies that do not export tend to fail to link their R&D investment to profitability. Second, this study finds that companies with huge investment on R&D for the future, which is the result of Proactivity, tend to hold a large number of patents (Creativity). And companies with significant numbers of patents tend to be large exporters as well (Opportunity), and companies with a large amount of exports tend to record high profitability (Productivity and profitability), and thus forms the virtuous cycle of the COPP model. In addition, to access global markets for sustainable growth, SMEs need to build and strengthen their competitiveness. This study concludes that companies with a high level of proactivity to invest for the future can create a virtuous circle of Creativity, Opportunity, Productivity, and Proactivity, thereby providing a strategic implication that SMEs should invest time and resources in forming such a virtuous cycle which is a sure way for the SMEs to grow into global small giants.

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