• Title/Summary/Keyword: Dry-Wall

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Nuritive Evalution of Forage Plants Grown in South Sulawesi, Indonesia

  • Nasrullah, Nasrullah;Niimi, M.;Akashi, R.;Kawamura, O.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.5
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    • pp.693-701
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    • 2003
  • In order to evaluate the nutritive value of the forage plants in South Sulawesi, Indonesia, 266 samples (61 grasses and 65 legumes grown in the dry season, 60 grasses and 80 legumes grown in the rainy season) were collected from the highland and lowland in 1998 to 2000, and were subjected to the determination of chemical composition and digestibility. The least-squares analysis of variance demonstrated that the in vitro dry matter digestibility (IVDMD) of grasses was not significantly affected by season or altitude. On the other hand, the some proximate components and cell wall components were significantly affected by season and altitude including the season${\times}$altitude interaction. For the legumes, the in vitro neutral detergent fiber digestibility (IVNDFD) and cellulose content were significantly affected by season. On the other hand, the ether extract (EE) content was significantly affected by season and altitude. The interaction of the season${\times}$altitude for IVDMD, of the year${\times}$season for some proximate components and of the year${\times}$season and the season${\times}$altitude for some cell wall components were significant. These results indicate that the forages grown at highland in dry season have a relatively high quality. The means of the total digestible nutrient (TDN) content estimated from IVDMD in grasses and in legumes were 50.3% and 57.4%, respectively, and the crude protein contents were 7.7% and 17.6%, respectively. The correlation coefficients between IVDMD and the contents of crude fiber, neutral detergent fiber and acid detergent fiber were relatively high in all of forage plants, suggesting that these components would provide an accurate prediction of digestibility or TDN content. A close relationship between IVNDFD and lignin content indicates that the lignin would be the most accurate predictor of cell wall digestibility.

An Experimental Study on Regime Limit and Pressure Drop of Dry-plug Flow in Round Mini-channels (원형 미소 채널 내 드라이 플러그류의 유동 영역 한계와 압력 강하에 관한 실험적 연구)

  • Lee, Chi-Young;Lee, Sang-Yong
    • Proceedings of the KSME Conference
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    • 2008.11b
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    • pp.2583-2588
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    • 2008
  • In the present experimental study, the regime limit and pressure drop of dry-plug flow (dry wall condition at the gas portions of plug flow) in round mini-channels has been investigated. The air-water mixture was flowed through the round mini-channels made of Teflon, where the tube diameters ranged from 1.26 to 2.06 mm. For the present experimental range, with decreasing of the tube diameter, the transition between the plug and slug flows (wet and dry) happened at the higher gas superficial velocity region, which were in good agreement with the previous flow pattern maps tested. On the other hand, the transition between the wet- and dry-plug flows was little affected by the change of the tube diameter. In the pressure drop of dry-plug flows, among the correlations tested, the Lee and Lee's (2008) correlation best fitted the measured pressure drop data within the mean deviation of 10% for the present experimental range.

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Comparative Study on the Effects of Combined Treatments of Lactic Acid Bacteria and Cellulases on the Cell Wall Compositions and the Digestibility of Rhodesgrass (Chloris gayana Kunth.) and Italian Ryegrass (Lolium multiflorum Lam.) Silages

  • Ridla, M.;Uchida, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.4
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    • pp.531-536
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    • 1999
  • This study was conducted to compare the effects of lactic acid bacteria (LAB) or LAB+cellulases on the cell wall compositions and the in vitro dry matter digestibility (IVDMD) of Rhodesgrass (RG) and Italian ryegrass (IRG) silages. LAB (Lactobacillus cassei) at a concentration of $10{\times}10^5\;cfu.g^{-1}$ fresh forage was added to all ensiling samples (except the untreated control) of RG and IRG. The cellulases used were Acremoniumcellulase (A), Meicelase (M) or a mixture of both (AM). Each cellulase was applied at levels of 0.005, 0.01 and 0.02 % fresh sample. The samples were incubated at 20, 30 and $40^{\circ}C$ for about 2 months of storage. LAB inoculation did not affect cell wall components or IVDMD of both the RG and IRG silages, but LAB+cellulase treatments did. Increasing the amount of cellulase addition resulted in further decreases of cell wall concentrations. This reduction more markedly occurred with cellulases A and AM than it did with cellulase M. Cell wall components losses were higher in the IRG silages than in the RG silages. LAB+cellulase treatments decreased IVDMD of the RG silages, but had no effect on the IRG silages. The different effect of LAB+cellulase treatments on cell wall degradation and IVDMD of the RG and IRG silages suggested that RG contains more structural carbohydrates, which were difficult to degrade with cellulase, than did IRG.

Behavior of underground strutted retaining structure under seismic condition

  • Chowdhury, Subha Sankar;Deb, Kousik;Sengupta, Aniruddha
    • Earthquakes and Structures
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    • v.8 no.5
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    • pp.1147-1170
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    • 2015
  • In this paper, the behavior of underground strutted retaining structure under seismic condition in non-liquefiable dry cohesionless soil is analyzed numerically. The numerical model is validated against the published results obtained from a study on embedded cantilever retaining wall under seismic condition. The validated model is used to investigate the difference between the static and seismic response of the structure in terms of four design parameters, e.g., support member or strut force, wall moment, lateral wall deflection and ground surface displacement. It is found that among the different design parameters, the one which is mostly affected by the earthquake force is wall deflection and the least affected is the strut force. To get the best possible results under seismic condition, the embedment depth of the wall and thickness of the wall can be chosen as around 100% and 6% of the depth of final excavation level, respectively. The stiffness of the strut may also be chosen as $5{\times}105kN/m/m$ to achieve best possible performance under seismic condition.

The Program of progress control and quality control for the high-rise compound building (초고층 주상복합건물의 수장공사 공정관리 및 품질관리 방안)

  • Jung, Eul-Kyu;Lim, Chil-Soon
    • Journal of the Korea Institute of Building Construction
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    • v.3 no.4
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    • pp.111-117
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    • 2003
  • Recently SAMWOO EMC received order and built interior walls which was used the day process in several high-rise compound buildings. On the way to build, this process was brought about several matter according to the progress and qualify control. So, this study is the improving way of the dry process from experiences on those constructions

Analysis of influence factors on the seismic earth pressure acting on gravity walls (중력식 옹벽에 작용하는 배면 동적 토력의 영향 인자 분석)

  • 윤석재;김성렬;김명모
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2002.09a
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    • pp.75-82
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    • 2002
  • The Mononobe-Okabe method is generally used to evaluate the dynamic earth force for the seismic design of retaining walls. However, the Mononobe-Okabe method does not consider the effects of the dynamic interactions between the backfill soil and the wall. In fact, a phase difference exists between the inertia force and the seismic earth pressure. In this study, shaking table tests were peformed on gravity walls retaining dry backfill sand to analyze the influence of several parameters (the unit weight of the wall, the input acceleration and base friction) on the development of the seismic earth pressure. The experiments revealed that the magnitude of the inertia force mobilized during seismic loading affected the seismic earth pressure. The difference in the phase angles between the inertia force and the seismic earth pressure was retained at 180 degrees before the wall failed but its magnitude changed significantly as the wall began to fail.

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Shear Performance of Hybrid Post and Beam Wall System Infilled with Structural Insulation Panel (SIP)

  • Shim, Kug-Bo;Hwang, Kweon-Hwan;Park, Joo-Saeng;Park, Moon-Jae
    • Journal of the Korean Wood Science and Technology
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    • v.38 no.5
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    • pp.405-413
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    • 2010
  • A hybrid post and beam shear wall system with structural insulation panel (SIP) infill was developed as a part of a green home 'Han-green' project through post and beam construction for contemporary life style. This project is on-going at the Korea Forest Research Institute to develop a new building system which improves Korean traditional wet-type building system and stimulates industrialized wood construction practice with pre-cut system. Compared to the traditional wet-type infill wall components, the hybrid wall system has benefits, such as, higher structural capacity, better thermal insulation performance, and shorter construction term due to the dry-type construction. To build up the hybrid wall system, in previous, SIP infill wall components can be manufactured at factory, and then inserted and nailed with helically threaded nails into the post and beam members at site. Shear performance of the hybrid wall system was evaluated through horizontal shear tests. The SIP hybrid wall system showed higher maximum shear strength, initial stiffness, ductility, yield strength, specified strength, and the specified allowable strength than those of post and beam with light-frame wall system. In addition to this, the hybrid wall system can provide speedy construction and structural and functional advantages including energy efficiency in the building system.

A Study on Heat Transfer Characteristics of a Closed Two-Phase Thermosyphon with a Low Tilt Angle (낮은 경사각을 갖는 밀폐형 2상 열사이폰의 열전달 특성에 관한 연구)

  • 김철주;강환국;김윤철
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.8 no.1
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    • pp.1-12
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    • 1996
  • In lots of application to heat exchanger systems, closed two-phase thermosyphons are tilted from a horizontal. If the tilt angle, especially, is less than 30$^{\circ}$, the operational performances of thermosyphon are highly dependent on tilt angle. The present study was conducted to better understand such operational behaviors as mech-anni는 of phase change, and flow patterns inside a tilted thermosyphon. For experiment, an ethanol thermosyphon with a 35% of fill charge rate was designed and manufactured, using a copper tube with a diameter 19mm and a length 1500mm. Through a series of test, the tilt angle was kept constant at each of 4 different values in the range 10~25deg. and the heat supply to the evaporator was stepwisely increased up to 30㎾/$m^2$. When a steady state was established to the thermosyphon for each step of thermal loads, the wall temperature distribution and vapor temperature at the condenser were measured. The wall temperature distributions demonstrated a formation of dry patch in the top end zone of the evaporator, with a values of temperature 20~4$0^{\circ}C$ higher than the wetted surface for a moderate heat flux q≒20㎾/$m^2$. Inspite of the presence of hot dry patch, however, the mean values of boiling heat transfer coefficient at the evaporator wall were still in a good agreement with those predicted by Rohsenow's formula, which was based on nucleate boiling. For the condenser, the wall temperatures were practically uniform, and the measured values of condensation heat transfer coefficient were 1.7 times higher than the predicted values obtained from Nusselt's film condensation theory on tilted plate. Using those two expressions, a correlation was formulated as a function of heat flux and tilt angle, to determine the total thermal resistance of a tilted thermosyphon. The correlation formula showed a good agreement with the experimental data within 20%.

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Earth Pressure Acting on the Diaphragm Wall of a Shaft in Cohesionless Soils (사질토지반에 설치된 원형수직구의 강성흙막이벽에 작용하는 토압)

  • Chun, Byung-Sik;Shin, Young-Wan;Kong, Jin-Young;Hwang, Yi-Sung
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.03a
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    • pp.734-741
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    • 2008
  • At-rest and active earth pressure in plane strain condition have been applied to the design of cylindrical retaining walls. But many researchers have indicated that the earth pressure on the cylindrical retaining walls would be smaller than in plane strain condition due to wall deformation and stress relief. In this paper, the distribution of earth pressure acting on diaphragm wall of a shaft in dry sand was predicted by using the convergence confinement method and model test was performed to verify the estimated values. Test results showed that the earth pressure acting on the diaphragm wall of a shaft was expected to be 1.1~1.5 times larger than active earth pressure of plane strain condition and 0.7~0.9 times less than at-rest earth pressure.

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Analysis of Lodging-Related Traits of Direct Seeded Rice

  • Kim, Hyun-Ho
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.43 no.1
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    • pp.32-37
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    • 1998
  • The objective of this study was to analyze lodging-related traits using different cultivars from Korea, Japan, and the U.S. in direct seeded rice on dry paddy field. Stem diameter and culm wall thickness were highest in 'Caloro' followed by 'Nongan', 'M202', and 'Calrose'. All the U.S. cultivars were higher than the others in stem diameter and culm wall thickness. These two traits were important with regard to lodging. The highest breaking strength (1442g) was observed in Caloro. 'Gancheoek', 'Dongjin', and transplanted 'Hatsuboshi' showed more than 1000g in breaking strength. Lodging index was lowest in Hatsuboshi followed by Nongan and Gancheok. Even though breaking strength of the U.S. cultivars was higher than others, their lodging index values were high. There were no statistically significant differences in starch content. However, Calrose, Caloro, Dongjin, and Koshihikari were relatively higher than others in starch content. Positive correlations were found between culm base weight, lignin and breaking strength. High contents of lignin and cellulose were observed in Nongan, transplanted Hatsuboshi, Calrose, and Caloro. Traits such as stem diameter, culm wall thickness, bending moment, culm length, breaking strength, cellulose, lignin, and culm base weight were closely related to a lodging index. According to path coefficient analysis, most important traits were culm length, stem diameter, thickness of clum wall, and top plant weight.

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