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A Study on Influencing factors and strategic market segmentation for diffusing ATCA based network equipments (ATCA 기반 통신 장비의 수요 요인 분석 및 도입 전략에 관한 연구)

  • Yoo Jae-heung;Ha Im-sook;Choi Mun-kee
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.7B
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    • pp.450-463
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    • 2005
  • This paper aims to find influencing factors for firms to adopt network equipments which based on Advanced Telecom Computing Architecture (ATCA). ATCA suggests a standardized specification for telecom equipments design. This new paradigm of developing network equipment provides benefits for network equipment manufacturers by reducing development time for new equipments with lower CapEx and OpEx. It also deliver oportunities for telecom services providers to exploit or test new services by replacing or upgrading part of total system with modular based network equipments. The research model basically depends on various researches based on Rogers' Innovation and Diffusion theory and it is verified through an empirical study for ninety-one domestic forms. Binary logistic regression was conducted to find the relationship between purchase intention and factors affecting new technology adoption. As a result, two factors such as scalability and cost/benefit effectiveness of the new system were statistically significant. Cluster analysis followed with those two variables. This helps TEMs (Telecom Equipments Manufacturers) get some implications on timing and target customers for diffusing the ATCA based technologies in the market.

Protective Effects of Fermented Aloe vera on Carbon Tetrachloride-induced Hepatotoxicity in Sprague-dawley Rats (사염화탄소 유도 간독성에 대한 발효알로에의 보호효과)

  • Lim, Byung-Lak
    • Microbiology and Biotechnology Letters
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    • v.36 no.3
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    • pp.240-245
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    • 2008
  • Aloe vera extract was fermented by Lactobacillus casei. The ability of fermented Aloe vera (FAV) as an antioxidant to protect against CCl4-induced oxidative stress and hepatotoxicity in rats was investigated. The rats were administered orally with various doses of FAV with 50, 100 mg/kg for 14 consecutive days. For this study, we not only tested activity of various plasma enzymes (AST, ALT), which are used as indicators of liver disease, but also checked those change of liver components such as superoxide dismutase and catalase activity. Pretreatment of FAV for two weeks significantly reduced the elevated plasma enzyme activities induced by CCl4. Pretreatment of FAV also restored the hepatic enzyme, malonedialdehyde (MDA) formation. The results indicate that FAV has a protective effect against acute hepatotoxicity induced by the administration of CCl4 in rats, and that the hepatoprotective effects of FAV may be due to both the inhibition of lipid peroxidation and the increase of antioxidant activity.

Cross-Sectional Velocity Variability and Tidal Exchanger in a Bay (만구를 통한 해수유출입과 만내수괴의 해수교환성)

  • 김종화
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.26 no.4
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    • pp.353-359
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    • 1990
  • Chinhae Bay, included small ports, is the region which the red tide phenomenon is occurred frequently in summer season. Field sampling of 4 cross-sections in the bay resulted in detailed informations on cross-sectional velocity distributions, salt concentrations and discharge during one consecutive tidal cycle in summer season, 1983. High velocity cores reoccur two times a semi-diurnal tidal cycle at the same cross-sectional location, lower layer, in Kadok Channel during the spring tide. The tidal exchange ratio was estimated by Eulerian method. The range of exchange ratios in central Kadok Channel are 9.3-17% at the spring tide and 16.9-21.8% at the neap tide. On the other hand, its range in Masan bay-mouth is 8.7% at the spring tide and 2.0% neap tide, respectively.

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Bee Venom Inhibits Prostate Cancer Growth in LNCaP Xenografts via Apoptosis (Bee venom의 세포자멸사를 통한 전립선 암세포의 성장 및 LNCaP의 이종이식에 미치는 영향)

  • Yang, Chang-Yeol;Song, Ho-Sueb
    • Journal of Pharmacopuncture
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    • v.13 no.1
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    • pp.15-35
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    • 2010
  • 연구목적 : 이 연구는 봉약침의 봉독이 NF-κB 활성억제와 안드로겐 수용체 조절 단백질 및 세포자멸사 조절 단백질의 발현을 통하여 세포자멸사를 유도하고, 전립선 암세포를 이식한 쥐에서의 세포자멸사 유도 효과를 확인함으로써, 봉약침의 봉독이 생체 내에서도 세포자멸사를 유도하여 전립선암에 효과를 나타냄을 확인하고자 하였다. 실험방법 : 세포자멸사의 관찰에는 DAPI, TUNEL staining assay를 시행하였으며, 세포자멸사 조절 단백질의 변동 관찰에는 western blot analysis를 시행하였고, 세포자멸사와 연관된 NF-κB의 활성 변화를 관찰하기 위해 EMSA를 시행하였다. 결과 : 1. DAPI, TUNEL staining assay 결과 봉독 및 melittin을 처리한 LNCaP 세포 모두에서 세포자멸사 유도율이 유의한 증가를 나타내었다. 2. LNCaP 세포에 봉독이나 melittin을 처리한 결과, 안드로겐 수용체 조절 단백질 중 p-Akt, COX-2, calpain은 봉독과 melittin 모두에서 유의한 감소를 나타내었고, Akt는 melittin에서 유의한 감소를 나타냈으며, 봉독에서 증가하는 경향을 보였고, MMP-9은 증가하였다. 3. 생체 내에서의 봉독의 항암효과를 확인하기 위해 전립선암세포가 이식된 쥐에 봉독을 처리한 후 암세포의 부피와 무게, 쥐의 체중을 측정한 결과, 봉독을 처리한 군에서 암 세포 부피비율 및 무게는 감소하였고, 쥐의 체중은 증가하였다. 4. 전립선암세포가 이식된 쥐에 봉독을 처리한 결과, NF-κB 활성에서 유의한 감소를 나타내었다. 5. 전립선암세포가 이식된 쥐에 봉독을 처리한 결과, 세포자멸사 조절 단백질 중 Bax/Bcl-2, p53, caspase-3, caspase-9, calpain은 유의한 증가를, COX-2는 유의한 감소를 나타냈으며, MMP-9는 증가를 나타내었다. 결론 : 이상의 결과는 봉독이 시험관 내에서 뿐만 아니라 생체 내에서도 NF-κB의 활성을 억제하고 안드로겐 수용체 조절 단백질 및 세포자멸사 조절 단백질의 조절을 통하여 인간 전립선암 세포주인 LNCaP의 세포자멸사를 유도함으로써 전립선암 세포 증식억제 효과 및 호르몬 비의존적인 전립선암으로의 전이를 지연시키는 경향이 있을 것으로 사료되고, 봉독이 전립선암의 예방과 치료에 효과적으로 활용될 수 있을 것으로 기대된다.

Apoptosis-Inducing Effect of Herba Patriniae Extract in Androgen Independent Prostate Cancer DU145 Cells (남성호르몬 비의존형 전립선 암세포에서 패장 추출물의 세포고사 유도 효과)

  • Kwon Kang Beom;Kim Eun Kyung;Ryu Cheal In;Park Hyung Kwon;Seong Ki Ho;Song Je Moon;Lee Kyung Yong;Kwon Young Dal;Seo Eun A;Ryu Do Gon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.6
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    • pp.1661-1665
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    • 2004
  • Herba Patriniae(HP) has been known to exert anti-tumoral activity in Korea. However, its molecular mechanism, of action is not understood. In this study, we found that HP induced apoptosis in androgen-dependent prostate cancer DU145 cells as evidenced by DNA fragmentation and chromatine condensation in hoechst dye staining. Our data demonstrated that HP-induced apoptotic cell death was accompanied by activation of caspase-3 and cleavages of its substrates, poly(ADP-ribose) polymerase(PARP) in a time- and concentration-dependent manner. Taken together, these results suggest that HP induces the activation of caspase-3, degradation of PARP, and eventually leads to apoptotic cell death.

Induction of Oocyte Ovulation and Prostaglandin Synthesis by Gonadotropin and Phorbol Ester in vitro in Amphibian (Rana n igromacu la ta) Ovarian Follicles (뇌하수체 호르몬과 포르볼에스터에 의한 참개구리 난자의 배란과 프로스타글라딘 합성유도)

  • 장경자;나철호;소재목;이원교;권혁방
    • The Korean Journal of Zoology
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    • v.39 no.3
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    • pp.266-272
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    • 1996
  • Experiments were carried out to ascertain whether gonadotropin or a phorbol ester (12-O-tetradecanoyl phorbol-13-acetate, TPA) induces oocyte ovulation and stimulates prostaglandin synthesis by Rana ovarian follicles in vitro. Rana nigromaculata collected from underground in spring were utilized for the present experiment. Treatment of frog pituitary homogenate (FPH) or TPA to ovarian fragments in culture induced oocyte ovulation in a dose dependent manner and stimulated prostaglandin F2a (PGF2α synthesis. Both treatruents were more effective in inducing the ovulation and PGF2α secretion by the follicles obtained in May than those in April. A Protein kinase C inactivator, 1-(5-isoquinolinyl-sulfonyl)-2-methyl-piperazine (H-7), or cyclooxygenase inhibitor, indomethacin (IM) suppressed the FPH- or TPA-induced PGF2α production, but IM failed to suppress the FPH- or TPA-induced ovulation. Time course of oocyte ovulation and PGF2α secretion by FPH and TPA treatments were very similar to each other. FPH stimulated progesterone secretion by the follicle but TPA failed to do so. Taken together, the data presented here suggest that protein kinase C (PKC) in follicle play a role in the ovulation process of Rana nigromaculata, probably via prostaglandin synthesis.

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Development of Digital Photogrammetric Systems for Three-Dimensional Topographic Information Analysis (3차원 지형정보분석을 위한 수치사진측량시스템 개발)

  • 유환희;안충현;오성남;성민규
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.17 no.1
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    • pp.11-19
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    • 1999
  • Lately, with the development of the fields of computer and photogrammetry, Digital Photogrammetric Systems are widely used for the generation of GIS basemap, the acquisition of topographic information and DEM, the formation of digital orthophoto, three-dimensional viewing and so on. According as the demand for the systems is rapidly increasing, we suggest keenly the necessity of domestic technical development, because all of these systems depend on foreign technology until now. In this study, by using digital photogrammetry method, with Visual C++ language, we have developed Digital Photogrammetric Systems for Windows which is able to get three-dimensional coordinates through interior orientation, exterior orientation, epipolar line, image matching from a pair of aerial photos taken with metric camera. This system consists of not only a module which can revise digital map that is being made at National Geographic Institute as a part of data construction project of National Geographic Information System, but also a module which can view three-dimensional image on the screen monitor by using anaglyph for three-dimensional analysis. The digital photogrammetry modules developed in this study are expected to be used as primary modules for the effective management of the urban as well as main modules in developing professional digital photogrammetric systems.

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Development of a numerical modelling technique for evaluation of a long-term chemical deterioration of tunnel shotcrete lining (터널 숏크리트 라이닝의 장기 화학적 열화 손상 평가를 위한 수치 모델링 기법 개발)

  • Shin, Hyu-Soung;Kim, Dong-Gyou
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.9 no.3
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    • pp.299-307
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    • 2007
  • In this study, a new concept for simulating a physical damage of tunnel shotcrete lining due to a long-term chemical deterioration has been proposed. It is known that the damage takes place mainly by internal cracks, reduction of stiffness and strength, which results mainly from volume expansion of the lining and corrosion of cement materials, respectively. This damage mechanism of shotcrete lining appears similar in most kinds of chemical reactions in tunnels. Therefore, the mechanical deterioration mechanism induced by a series of chemical reactions was generalized in this study and mathematically formulated in the framework of thermodynamics. The numerical model was implemented to a 3D finite element code, which can be used to simulate behaviour of tunnel structures undergoing external loads as well as chemical deterioration in time. A number of illustrative examples were given to show a feasibility of the model in tunnel designs.

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Prelinimary Engagement Effect Analysis of Isotropic Kinetic Energy Warhead (등방성 운동에너지 탄두의 교전 효과 예비 분석)

  • Shim, Sang-Wook;Hong, Seong-Min;Seo, Min-Guk;Tahk, Min-Jea
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.43 no.5
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    • pp.440-448
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    • 2015
  • Kinetic energy(KE) rod warhead system is a new interceptor which combines advantages of existing ones. This system is less dependant on a precision guidance than direct hit type warhead and gives high penetration rates than blast fragmentation type warhead. In this paper, isotropic KE rod warhead system is introduced with detonation/deployment model. A penetration effects of the deployed rods are calculated using TATE penetration equation. Also, an engagement performance analysis method is suggested. Finally, an optimal detonation time and engagement geometry is derived by Monte-Carlo simulation in various engagement situation using the performance analysis factor.

Development of Edge Milling Automation System for PSPC Application (PSPC 적용을 위한 모서리 밀링 자동화 시스템 개발)

  • Ryu, Hyun-Su;Park, Il-Hwan;Ko, Dae-Eun;Kim, Ho-Kyeong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.5
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    • pp.122-130
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    • 2018
  • The International Maritime Organization has enacted mandatory performance standards for protective coatings (PSPC), and as a result, shipyards must perform 2R or 3-pass milling on the edges of color plates. However, manual milling could result in many problems in terms of work environment and productivity. Therefore, it is necessary to develop an edge milling automation system that can satisfy the regulations. In this study, a basic design for an edge milling automation system was developed for standard color plates, and the machining process was established by applying shape recognition and a machining path generation algorithm. In addition, operating software was developed, and suitable milling conditions were derived based on the results of a milling test. The results could be used to build an automation system that meets the PSPC requirements and improve productivity.