• Title/Summary/Keyword: Mat

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An Experimental Study on Solidifying Mat of System Improving for Durability Improving (고화매트의 내구성 향상을 위한 시스템 개선의 실험적 연구)

  • Hong, Sung-Rog;Lee, Jung-Yoon;Kim, Young-Sam;Park, Hun-Il;Cho, Byoung-Young
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2014.05a
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    • pp.108-109
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    • 2014
  • The purpose of this study is to enhance durability of solidifying mat. solidifying mat excellent mechanical properties of geotextile. multi-layer coating system is applied to the mat and the chloride ions penetration resistance, chemical resistance, accelerated carbonation test were evaluated by testing the durability. Durability test results are as follows. chloride ions penetration resistance results are coated mat is approximately 70 % lower than plain. chemical resistance test results are coated mat no discoloration. accelerated carbonation test results are coated mat is approximately 90 % lower than the plain.

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Inverse Relationship of Hemiptera Richness with Temperature in South Korea

  • Kwon, Tae-Sung;Jung, Sungcheol;Park, Young-Seuk
    • Korean Journal of Ecology and Environment
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    • v.54 no.2
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    • pp.102-107
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    • 2021
  • The distribution pattern of species richness was determined by temperature. To examine the relationship between hemipteran richness and temperature, hemipteran species were collected using pitfall traps at six different oak forest sites with different annual mean temperatures in South Korea. Multiple linear regression analyses were conducted with mean annual temperature (MAT) and plant richness to evaluate differences in hemipteran richness. The influences of MAT and plant richness of study sites on hemipteran richness were examined by comparing three models (plant richness+MAT+MAT2, plant richness+MAT, and MAT) or two models (plant richness+MAT and MAT). Hemipteran richness showed an inverse diversity pattern as a function of temperature, with higher species richness at lower temperature sites. Meanwhile, Aphididae showed a bell-shaped diversity pattern with the highest value at low medium temperatures. The regression analysis showed that hemipteran richness was affected by temperature and plant richness in their habitats.

An Experimental Study for Substitutability of Sand Mat with Fiber Mat (Fiber Mat의 Sand Mat 대체가능성평가를 위한 실험적 연구)

  • Lee Song;Jeong Yong-Eun
    • Journal of the Korean Geotechnical Society
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    • v.21 no.5
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    • pp.225-230
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    • 2005
  • At present, there are several problems related with sand mat which is used as a way to accelerate consolidation settlement, to act like an underground drainage layer and to increase trafficability simultaneously. First of all, the unbalance of the demand and supply of sand is one of the biggest problems, which causes not only price rise but also delay of the term of the total construction work. Secondly, the damage of ecosystem and scenery is triggered by thoughtless sand dredging or mining. So, the need that sand mat should be replaced with a new environmentally friendly material has been increased. Fiber mat may be one of the proper materials that suits the need. Therefore, we intended to compare the drainage properties of sand mat with those of fiber mat by experimental model tests. On the basis of the test results, fiber mat took shorter period of consolidation than sand mat and the amount of settlement in the farmer showed a little bit bigger than in the latter. As a conclusion, the substitutability of sand mat with fiber mat could be placed highly in view of drainage efficiency. Furthermore, when fiber mat is used, it has an advantage that spoiled soil of the construction site or nearby site can be used for the purpose of increasing trafficability in addition to a role of drainage layer.

Evaluation of Non-slip for Vehicle's Environmental Sub-Mat (자동차용 친환경적인 Sub-Mat의 Non-Slip기능 평가)

  • Eo, Yu-Rim;Kim, Ki-Tai;Kim, Joo-Yong;Kim, Young-Su
    • Science of Emotion and Sensibility
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    • v.15 no.2
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    • pp.177-182
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    • 2012
  • Automotive sub-mat carpet for convenience and comfort of floor administration is additional supplemented floor mat. Sub Mat Backing of the current vehicle's materials reclaimed rubber, PVC, etc. are used, but secondary rubber and PVC Backing have bad sound absorption. Also rubber is heavy too. Contact surfaces between PET staple fiber, PET non-woven, PVC backing and car's floor carpet was measured the coefficient of friction for each sub-mat's non-slip evaluation. A surface of PET non-woven sub-mat has the highest coefficient of friction. Each of sample was observed by optical microscope the contact surfaces before and after. Contact surfaces of PET staple fiber sub-mat was changed increasingly to non-woven. This fact is shown that the sub-mat would be tangled between its contact surface and top of the floor carpet. It is expected to be highly non-slip. In case of PET non-woven sub-mat had not different for contact surfaces between before and after. And PVC backing was shown lower non-slip than other samples. The result of optical microscope and coefficient of friction is seems to be related.

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Molecular Comparison of Mating Type Loci and Adjacent Chromosomal Regions from Self-fertile and Self-sterile Cochliobolus Species

  • Yun, Sung-Hwan;B. Gillian Turgeon;Turgeon
    • The Plant Pathology Journal
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    • v.15 no.3
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    • pp.131-136
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    • 1999
  • In fungi known as ascomycetes, ability to mate is controlled by a single mating type (MAT) locus with two dissimilar sequences called idiomorphs carrying genes encoding transcription factors that are unrelated to each other. Fungi requiring strains with different MAT genes to complete the sexual process are heterothallic (self-sterile); species in which as single strain is able to undergo sexual reproduction are homothallic (self-fertile). Previous analysis of sequences from several heterothallic and homothallic species of the ascomycete genus Cochliobolus showed that homothallics evolve from heterothallics and that each known Cochliobolus homothallic species arose independently, from a different heterothallic ancestral species. Here we report detailed comparative analyses of MAT sequences ad their flanking regions, and show that: (1) The level of MAT gene similarity is not correlated with reproductive life style; (2) MAT proteins from all Cochliobolus species are conserved within the transcription factor signature sequences; they are not conserved in the carboxy terminal half of MAT-1, or third of MAT-2, except in those from very closely related species; (3) A gene (ORF1) of unknown function, consistently found on the MAT flank, is more conserved than are the MAT genes themselves; (4) The intergenic sequences diverge sharply among species.

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Control of Turbid Water Transport with Filamentous Mat (섬모상 매트에 의한 탁수이동차단에 관한 실험적 연구)

  • Yu, Jianghua;Yi, Qitao;Kim, Youngchul
    • Journal of Korean Society on Water Environment
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    • v.26 no.1
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    • pp.44-51
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    • 2010
  • A lab-scale apparatus for turbid water transport control was tested and examined. The channel had a dimension of $100cm{\times}30cm{\times}15cm$ (length${\times}$hight${\times}$width). And the turbidity water was prepared using two types of particles, bentonite and loess. The channel equipped with filamentous mat was operated under various shock load conditions. In the control channel, instantly, turbid water mixed with the clean water inside the channel and turbidity prevails the entire channel. While in the mat-equipped channel, it increases only at the bottom. Overall, the filamentous mat gave capture efficiency of 70~90% compared with the control group. The capture efficiency of turbid particles decreased with increased input turbidity flux. The result of experimental run on how turbid particles are separated in the mat channel shows that settling, filtration and attachment are the main processes. Meanwhile, turbidity was diffused from the channel bottom due to turbidity gradient before and after mat zone. The particle size before mat zone was lightly coarser than that after mat zone.

Effect of a Sunken Mat Foundation on the Horizontal Design Spectrum of a Structure (깊게 파인 온통기초가 구조물의 수평방향 설계스펙트럼에 미치는 영향)

  • Kim, Yong-Seok
    • Journal of the Earthquake Engineering Society of Korea
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    • v.25 no.4
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    • pp.169-177
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    • 2021
  • In this paper, horizontal seismic responses of a structure built on a sunken mat foundation were compared with those built on a solid embedded mat foundation to investigate the effect of a sunken mat foundation on the horizontal response of a structure. Seismic analyses of a structure laid on the embedded mat foundation were performed by utilizing a pseudo-3D finite element software of P3DASS. Three bedrock earthquake records downloaded from the Pacific Earthquake Engineering Research Center database were scaled to reproduce weak-moderate earthquakes. Weak, medium, and stiff soil layers were considered for the seismic analyses of the structure-foundation-soil system. Parametric studies were performed for foundation radius, foundation embedment depth, and shear wave velocity of a soil layer to investigate their effect on the seismic response spectrum. The study result showed that the design spectrum of a structure built on a sunken mat foundation was similar to that with a solid embedded mat foundation showing a slight difference due to almost the same seismic base motion beneath both embedded foundations.

O-CDMA Code Acquisition Algorithm Based on Magnitude and Sign of Correlation Values (상관값의 크기와 부호에 기반한 O-CDMA 부호 획득 알고리즘)

  • Chong, Da-Hae;Yoon, Tae-Ung;Lee, Young-Po;Lee, Young-Yoon;Song, Chong-Han;Park, So-Ryoung;Yoon, Seok-Ho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.6C
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    • pp.649-655
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    • 2009
  • Mean acquisition time (MAT) is the most important performance measure for code acquisition systems, where a shorter MAT implies a better code acquisition performance. Keshavarzian and Salehi proposed the multiple-shift (MS) algorithm for code acquisition in optical code division multiple access (O-CDMA) systems. Performing two steps acquisition, the MS algorithm has a shorter MAT than that of the conventional serial-search (SS) algorithm. In this paper, we propose a rapid code acquisition algorithm for O-CDMA systems. By using an efficient combination of local signals, correlation value, and the sign of correlation value, the proposed algorithm can provide a shorter MAT compared with that of the MS algorithm. The simulation results show that the proposed algorithm presents a shorter MAT than that of the MS algorithm.

Analysis of the MAT1-1 and MAT1-2 Gene Ratio in Black Koji Molds Isolated from Meju

  • Mageswari, Anbazhagan;Kim, Jeong-seon;Cheon, Kyu-Ho;Kwon, Soon-Wo;Yamada, Osamu;Hong, Seung-Beom
    • Mycobiology
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    • v.44 no.4
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    • pp.269-276
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    • 2016
  • Aspergillus luchuensis is known as an industrially important fungal species used for making fermented foods such as awamori and shochu in Japan, makgeolli and Meju in Korea, and Pu-erh tea in China. Nonetheless, this species has not yet been widely studied regarding mating-type genes. In this study, we examined the MAT1-1 and MAT1-2 gene ratio in black koji molds (A. luchuensis, Aspergillus niger, and Aspergillus tubingensis) and in Aspergillus welwitschiae isolated from Meju, a fermented soybean starting material for traditional soy sauce and soybean paste in Korea. The number of strains with the MAT1-1 locus was 2 of 23 (A. luchuensis), 6 of 13 (A. tubingensis), 21 of 28 (A. niger), and 5 of 10 (A. welwitschiae). Fungal species A. tubingensis and A. welwitschiae showed a 1 : 1 ratio of MAT1-1 and MAT1-2 mating-type loci. In contrast, A. luchuensis revealed predominance of MAT1-2 (91.3%) and A. niger of MAT1-1 (75%). We isolated and identified 2 A. luchuensis MAT1-1 strains from Meju, although all strains for making shochu in Japan are of the MAT1-2 type. These strains may be a good resource for breeding of A. luchuensis to be used in the Asian fermented-food industry.