• Title/Summary/Keyword: intensity of extention

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p-Version Finite Element Model of Cracked Plates Including Shear Deformation under Flexural Behavior (휨거동을 받는 균열판의 전단변형을 고려한 p-Version 유한요소모델)

  • Lee, C.G.;K.S.Woo;Shin, Y.S.
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1993.10a
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    • pp.16-23
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    • 1993
  • The new p-version crack model is proposed to estimate the bending stress intensity factors of the thick cracked plate under flexure. The proposed model is based on high order theory and $C^{\circ}$-plate element including shear deformation. The displacements fields are defined by integrals of Legerdre polynomials which can be classified into three groups such as basic mode, side mode and internal mode. The computer implementation allows arbitrary variations of p-level up to a maximum value of 10. The bending stress intensity factors are computed by virtual crack extention approach. The effects of ratios of thickness to crack length(h/a), crack length to width(a/W) and boundary conditions are investigated. Very good agreement with the existing solution in the literature are shown for the uncracked plate as well as the cracked plate.

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Effect of the light qualities on the growth characteristics and yield in the cultivation of Lyophyllum ulmarium (만가닥버섯 재배시 광 종류에 따른 생육 특성 및 수량)

  • Park, Jae-Seong;Choi, Jae-Sun;Rho, Chang-Woo;Yun, Tae;Lee, Chang-Soo
    • Journal of Mushroom
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    • v.8 no.4
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    • pp.137-141
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    • 2010
  • This experiment was carried out to clarify the effect of light qualities on the growth characteristics and yield of fruiting body in the cultivation of Lyophyllum ulmarium. The intensity of illumination by light qualities was in the order of white light(2,270Lux), yellow light(1,750Lux), blue light(460Lux) and red light(400Lux). An investigation of fruiting body showed these results that the pileus size and stipe diameter of fruiting body on CBM(Chungbuk mushroom)-1757 were much larger than Hypsizigus marmoreus, and an effect of yellow light seemed to be better than those of another light. In comparison with Hypsizigus marmoreus, the growth duration of CBM-1757 was shortened by 8 days which included 2 days for mycelial culture, 1 day for first pinning requirement and 1 day for growth. The growth duration in yellow light illumination was about 70 days showing the tendency of 2~4 days reduction. There were no differences in results such as number of effective stem and fresh weight. The yield of fruiting body per bottle in CBM-1757(95.6g) was little higher than Hypsizigus marmoreus(94.8g). By a white light's standard, the yields of blue and red light illumination were decreased by 2~9%, but that of yellow light illumination was increased by 8%. The chromaticity results showed that brightness, red and yellow coloration of CBM-1757 were higher than those of Hypsizigus marmoreus, and yellow light treatment was more effective than another light.

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p-Version Finite Element Model of Cracked Thick Plates Including Shear Deformation under Flexure (휨을 받는 두꺼운 균열판의 전단변형을 고려한 p-Version 유한요소모델)

  • Lee, Chae Gyu;Woo, Kwang Sung;Shin, Young Shik
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.14 no.6
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    • pp.1289-1298
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    • 1994
  • The new p-version crack model is proposed to estimate the stress intensity factors of the thick cracked plate under flexure. The proposed model is based on high order theory and $C^{\circ}$-plate element including shear deformation. The displacements fields are defined by integrals of Legendre polynomials which can be classified into three groups such as basic mode, side mode and internal mode. The computer implementation allows arbitrary variations of p-level Up to a maximum value of 10. The stress intensity factors are computed by virtual crack extention approach. The effects of ratios of thickness to crack length(h/a), crack length to width(a/W) and boundary conditions are investigated. Very good agreement with the existing solution in the literature are shown for the uncracked plate as well as the cracked plate.

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Mechanical Properties and Synthesis of Polyurethane Dispersion by Glycerol for Vegetable Leather Surface Coatings (Vegetable Leather 표면코팅에 대한 Glycerol을 이용한 수분산 폴리우레탄의 합성 및 기계적 특성)

  • Lee, Joo-Youb
    • Journal of the Korean Applied Science and Technology
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    • v.32 no.1
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    • pp.100-107
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    • 2015
  • Prepared polyurethane resin for vegetable leather coating on surface was synthesized with glycerol which had different mole ratio. Mechanical properties of the synthesized polyurethane resin were measured by the SEM, FT-IR, UTM. Growing concerns in the evnironment-friendly polymer resin, we have synthesized low late obtained solvent water dispersion resin to be coating on vegetable leather. The increase of aliphatic trihydric alcohol glycerol mole %, abrasion resistance and tensile strength had highly stronger in intensity and longer durability. On the contrary, demonstrated reduce properties of elongation and flexibility. In the result of toluene solvent resistance, there was no effect of increased or decreased by the ratio of glycerol mole %.

Photosynthetic, Morphological and Growing Characteristics by Shading Materials in Panax ginseng C. A. Meyer (차광재 종류가 묘삼의 광합성, 형태 및 생육에 미치는 영향)

  • Cho, Jin-Woong;Park, Hong-Woo;Kim, Min-Jung;Kim, Hyun-Ho;Choi, Jae-Eul
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.53 no.3
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    • pp.256-260
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    • 2008
  • This study was conducted to response the photosynthetic rate and anatomical characters in one year ginseng plant against the light transmission ratio (10%, 20% and 30% in natural light) under shading materials by polyethylene (PE) net. The chlorophyll content and the photosynthesis of ginseng according to the light transmissivity showed decreasing trend as the light transmission ratio increased. At the higher light transmission ratio condition, leaves showed the chlorosis due to the physiological disorder, stems formed hypodermis, and phloem development inside the vascular tissue shrunk remarkably. Also, roots showed the epidermis destruction and less cambium development at the higher light intensity. The root weight also decreased as the light transmission ratio increased.

Mechanical Deterioration Characteristics of ACSR due to a Flame (화염으로 인한 ACSR의 기계적 열화 특성)

  • 박창기;이광식;강지원;김영달
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.17 no.6
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    • pp.160-168
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    • 2003
  • In Korea, a large portion of aerial power-transmission cables is installed in the mountains. In the case of a fire in the mountains, steel wires coated with zinc and aluminum wires of those power cables exposed to the fire or near around will be deteriorated by the blaze and the high temperature. Deterioration proceeds by interactions of a variety of factors like quality, manufacturing process, the condition of installation and exposure environment of a wire, and so on. Generally, the characteristic of a conductor affect by a forest fire can not be analyzed without the effect through simulating a forest fire. However, there are little research accomplishments of that kind of simulation about it, and there's been no analysis of a sample exposed to an actual forest fire. This thesis shows the experimental results that apply to a new wire by an artificial flame-maker because it's difficult to directly analyze the characteristic of deterioration by a forest fire. Those results include the intensity of extension and wrench for a conductor. In addition, there's been an experiment and analysis about the mechanical characteristics of the wire of ACSR 480[$\textrm{mm}^2$] which was removed from Pohang area by a forest fire. Then, the database will be made to predict the state of deteriorated wires by a forest fire using those two data, and data necessary to diagnose the life state of an ACSR wire affected by a forest fire will be given.

Applicability of plate tectonics to the post-late Cretaceous igneous activities and mineralization in the southern part of South Korea( I ) (한국남부(韓國南部)의 백악기말(白堊紀末) 이후(以後)의 화성활동(火成活動)과 광화작용(鑛化作用)에 대(對)한 판구조론(板構造論)의 적용성(適用性) 연구(硏究)( I ))

  • Min, Kyung Duck;Kim, Ok Joon;Yun, Suckew;Lee, Dai Sung;Joo, Sung Whan
    • Economic and Environmental Geology
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    • v.15 no.3
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    • pp.123-154
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    • 1982
  • Petrochemical, K-Ar dating, Sand Rb/Sr isotopes, metallogenic zoning, paleomagnetic and geotectonic studies of the Gyongsang basin were carried out to examine applicability of plate tectonics to the post-late Cretaceous igneous activity and metallogeny in the southeastern part of Korean Peninsula. The results obtained are as follows: 1. Bulgugsa granitic rocks range from granite to adamellite, whose Q-Ab-Or triangular diagram indicates that the depth and pressure at which the magma consolidated increase from coast to inland varying from 6 km, 0.5-3.3 kb in the coastal area to 17 km, 0.5-10 kb in the inland area. 2. The volcanic rocks in Gyongsang basin range from andesitic to basaltic rocks, and the basaltic rocks are generally tholeiitic in the coastal area and alkali basalt in the inland area. 3. The volcanic rocks of the area have the initial ratio of Sr^{87}/Sr^{86} varying from 0.706 to 0.707 which suggests a continental origin; the ratio of Rb/Sr changing from 0.079-0.157 in the coastal area to 0.021-0.034 in the inland area suggests that the volcanism is getting younger toward coastal side, which may indicate a retreat in stage of differentiation if they were derived from a same magma. The K_2O/SiO_2 (60%) increases from about 1.0 in the coastal area to about 3.0 in the inland area, which may suggest an increase indepth of the Benioff zone, if existed, toward inland side. 4. The K-Ar ages of volcanic rocks were measured to be 79.4 m.y. near Daegu, and 61.7 m.y. near Busan indicating a southeastward decrease in age. The ages of plutonic rocks also decrease toward the same direction with 73 m.y. near Daegu, and 58 m.y. near Busan, so that the volcanism predated the plutonism by 6 m.y. in the continental interior and 4 m.y. along the coast. Such igneous activities provide a positive evidence for an applicability of plate tectonics to this area. 5. Sulfur isotope analyses of sulfide minerals from 8 mines revealed that these deposits were genetically connected with the spacially associated ingeous rocks showing relatively narrow range of ${\delta}^{34}S$ values (-0.9‰ to +7.5‰ except for +13.3 from Mulgum Mine). A sequence of metallogenic zones from the coast to the inland is delineated to be in the order of Fe-Cu zone, Cu-Pb-Zn zone, and W-Mo zone. A few porphyry type copper deposits are found in the Fe-Cu zone. These two facts enable the sequence to be comparable with that of Andean type in South America. 6. The VGP's of Cretaceous and post Cretaceous rocks from Korea are located near the ones($71^{\circ}N$, $180^{\circ}E$ and $90^{\circ}N$, $110^{\circ}E$) obtained from continents of northern hemisphere. This suggests that the Korean peninsula has been stable tectonically since Cretaceous, belonging to the Eurasian continent. 7. Different polar wandering path between Korean peninsula and Japanese islands delineates that there has been some relative movement between them. 8. The variational feature of declination of NRM toward northwestern inland side from southeastern extremity of Korean peninsula suggests that the age of rocks becomes older toward inland side. 9. The geological structure(mainly faults) and trends of lineaments interpreted from the Landsat imagery reveal that NNE-, NWW- and NEE-trends are predominant in the decreasing order of intensity. 10. The NNE-trending structures were originated by tensional and/or compressional forces, the directions of which were parallel and perpendicular respectively to the subduction boundary of the Kula plate during about 90 m.y. B.P. The NWW-trending structures were originated as shear fractures by the same compressional forces. The NEE-trending structures are considered to be priginated as tension fractures parallel to the subduction boundary of the Kula plate during about 70 m.y. B.P. when Japanese islands had drifted toward southeast leaving the Sea of Japan behind. It was clearly demonstrated by many authors that the drifting of Japanese islands was accompanied with a rotational movement of a clock-wise direction, so that it is inferred that subduction boundary had changed from NNE- to NEE-direction. A number of facts and features mentioned above provide a suite of positive evidences enabling application of plate tectonics to the late Cretaceous-early Tertiary igneous activity and metallogeny in the area. Synthesizing these facts, an arc-trench system of continental margin-type is adopted by reconstructing paleogeographic models for the evolution of Korean peninsula and Japan islands. The models involve an extention mechanism behind the are(proto-Japan), by which proto-Japan as of northeastern continuation of Gyongsang zone has been drifted rotationally toward southeast. The zone of igneous activity has also been migrated from the inland in late-Cretaceous to the peninsula margin and southwestern Japan in Tertiary.

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