• Journal of Welding and Joining
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• v.30 no.6
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• pp.80-85
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• 2012

Fatigue cracks in structural components are the most common cause of structural failure when exposed to fatigue loading. In this respect, fatigue crack detection and structural health assessment are very important. Currently, various smart materials are used for detecting fatigue crack and measurement of SIFs(Stress Intensity Factors). So, this paper presented a measurement of SIFs using MFC(Micro Fiber Composite) sensor which is the one of the smart material. MFC sensor is more flexible, durable and reliable than other smart materials. The SIFs of Mode I(K I) as well as Mode II(K II) based on the piezoelectric constitutive law and fracture mechanics are calculated. In this study, the SIF values measured by MFC sensors are compared with the theoretical results.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.359-364
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• 2004

In this study, experiments were tried on the mixed-mode I+II single overloading model which changes the loading mode of overload and fatigue load. Aspects of deformation field in front of the crack which is formed by mixed-mode I+II single overloading were experimentally studied. Then the shape and size of mixed-mode plastic zone were approximately calculated. The propagation behavior of fatigue crack was examined under the test conditions combined by changing the loading mode. The behavior of fatigue cracks were greatly affected by shapes of plastic deformation field and applying mode of fatigue load. Accuracy of prediction and evaluation for fatigue life may be improved by considering all aspects of deformation and behavior of fatigue cracks.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.69-69
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• 2003

Although effect of TGF$\beta$$_1$ on preimplantation embryo development was reported at mice, little information relevant to this subject is known in bovine. The objectives of this study were to investigate TGF$\beta$$_1$, and TGF$\beta$$_1$ receptors type I and II expression, known as important factors in the embryo development, at unfertilized oocytes and fertilized embryos that will be used as basic data to be compared to NT embryos. We postulated that TGF$\beta$$_1$ may have a beneficial effect on the preimplantation embryo and show different expression patterns as embryo stages change. We have used immunocytochemistry to investigate the presence in unfertilized oocytes and preimplantation embryos of TGF$\beta$$_1$ and the essential components of the TGF$\beta$$_1$ signalling pathway, TGF$\beta$$_1$ receptors type I and II. We found that both receptors, as well as TGF$\beta$$_1$, were present in the unfertilized oocytes. This indicates that TGF$\beta$$_1$, is a maternally expressed protein. At the morulae and blastocyst stages the TGF$\beta$$_1$ receptor type II was not present, but the TGF$\beta$$_1$ receptor type I was present at both stages and we can confirm the TGF$\beta$$_1$ expression of high level at 8-cell stage. These findings support our hypothesis that the TGF$\beta$$_1$, and TGF$\beta$$_1$ receptors may interact with the oocyte and preimplantation embryo, and that TGF$\beta$$_1$ signalling may be important for the development of the oocyte and the preimplahtation embryo.

• Archives of Pharmacal Research
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• v.22 no.6
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• pp.642-645
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• 1999

In a bioassay-guided search for anti-allergic compounds from higher plants of Korea, poly-methoxyflavones, 3',4',5,6,7,8-hexamethoxyflavone (I), 5-hydroxy-3',4',6,7,8-pentamethoxyflavone (II) and 3',4',5,7,8-pentamethoxyflavone (III) have been isolated from the immature peels of Citrus unshiu. Structures of these compounds were elucidated on the basis of spectroscopic techniques. Compounds I and II inhibited dose-dependent histamine release from the rat peritoneal mast cells activated by compound 48/80 or anti-DNP IgE.

• The Korean Journal of Ecology
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• v.4 no.1_2
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• pp.25-32
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• 1981

During the period of 1975∼77, a survey and an investigation were carried out to estimate the frequency of lime-chlorosis in the natural vegetation in Korea and the relationships between plants and calcareous soils. The symptoms of lime-chlorosis were observed in flowering plants in the calcareous areas of Weonju (I, II), Yeongweol(I, II), Jecheon, Danyang and Samcheok. Although the species found to be lime-chlorotic on at least one occasion numbered 60, the total quantity of lime-chlorotic foliage observed was small. Severe lime-chlorosis of Capsicuym annuum in agricultural fields was found out at Danyang. However, some of the species which were of widespread occurrence in affected areas showed no lime-chlorosis. The comparison of the inorganic components in calcareous soils in lime-chlorotic and normal leaves showed that the essential mineral nutrients substantially less soluble in water in alkaline than in acid conditions and calcifuges planted on calcareous soils often show visual signs resembling those of P or Fe deficiency.

• Korean Journal of Food Science and Technology
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• v.51 no.3
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• pp.278-285
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• 2019

Tomato (Lycopersicon esculentum) is widely known for its beneficial effects on human health. To investigate the beneficial effects of polysaccharides from cherry tomato, cherry tomato polysaccharides (CTP) were prepared, the component sugars were analyzed, and the immunomodulatory activities in RAW 264.7 macrophages were assessed. CTP mainly contained arabinose (Ara) and galactose (Gal), suggesting that CTP might be enriched with an arabinogalactan (AG) moiety. The Ara and Gal present in CTP are likely components of AG-II (35.4%), namely $arabino-{\beta}-(3,6)-galactan$. To investigate the immunomodulatory activity of CTP, cytokine levels and iNOS2, COX-2, and $NF-{\kappa}B$ protein levels were analyzed, and $NF-{\kappa}B$ nuclear translocation and phagocytosis were observed by immunofluorescence. CTP significantly increased the levels of $TNF-{\alpha}$, MCP-1, and IL-6. CTP also increased iNOS2 and COX-2 expression as well as $NF-{\kappa}B$ nuclear translocation in RAW 264.7 cells. CTP significantly stimulated phagocytosis activity. These results showed that CTP stimulates macrophage activity, which can boost the innate immune response. CTP with high AG-II content could be used as a prebiotic to strengthen immunity.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.613-615
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• 2009

This paper is to introduce Hanwha Aerospace R&D Center's development status of TVC(Thrust Vector Control) system and control valves for Korean space launch vehicles. With the successful development of KSR-III TVC system, Hanwha have developed TVC system and RCS control valves for KSLV-I. Also, in the advance research area of KSLV-II, Hanwha have participated in LOx and fuel flow control valves and LOx shut-off valve development in the engine supply system. Based on the accumulated experiences and technologies in the aerospace key components and system development, Hanwha will make an important contribution to KSLV-II development in the future.

• Journal of the Korean Society of Safety
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• v.22 no.3 s.81
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• pp.65-73
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• 2007

This paper presents the safety performance of Korean domestic construction companies including the characteristic and current status of safety management actions of the firms. Safety performance both at the head office and job sites of each construction companies, which are divided four groups by construction capacity ranking, are investigated. General recognition that there is a wide difference of safety performance among domestic construction companies by construction capacity ranking was confirmed by comparing the safety performance at the head office and the job sites of the companies under the study. Data analysis shows that the safety performance of the group I and II has the largest difference, and this difference of the group II and III and group III and IV are gradually decreased, respectively. This paper presents the safety performance improvement measures, which is applicable to safety management components consisting of both the head office and job sites safety management systems of each group (e.g., I, II, III and IV) suffering the lack of safety performance.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.56.1-56.1
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• 2016

A low-mass star-forming region, L1251B, is an excellent example of a small and nearby group of protostellar objects. L1251B has been mapped spectroscopically with the Infrared Spectrograph (IRS) onboard the Spitzer Space Telescope. IRS has provided mid-IR emission lines (e.g., [Fe II], [Ne II], and ro-vibrational H2) and absorption features of CO2 and H2O ice in studying the physical state of the ionized gas and the material residing in the circumstellar environments. We will present the distribution of outflows and ice components in L1251B.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.81.1-81.1
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• 2017

L1251B is an excellent example of a small group of pre- and protostellar objects in low-mass star-forming region. Previous interferometer data with a high angular resolution resolved the outflows associated with L1251B into a few components. To understand the physical conditions of the protostellar outflows in L1251B, we mapped this region spectroscopically with Spitzer/IRS and obtained spectral line data from Herschel/PACS. Spitzer/IRS provides the S(0)-S(7) pure rotational lines of H2 as well as fine-structure emissions produced in shocks such as S, [Si II], and [Fe II] and it is a powerful tool for studying shocked interstellar gas. In addition, [O I] lines observed with Herschel/PACS are described well by J-type shock models expected in the outflows from protostars. We will present an analysis of the L1251B protostellar outflow in the H2 pure rotational lines and fine-structure emissions.