• Title/Summary/Keyword: Bed-log

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An Experimental Study on Flow Characteristics in the Open Annular Flume (환형수조에서 흐름특성에 관한 실험적 연구)

  • Choi, In Ho;Kim, Jong Woo
    • Journal of Wetlands Research
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    • v.21 no.3
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    • pp.207-214
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    • 2019
  • This study investigated the flow characteristics in an annular flume with a free water surface using the Acoustic Doppler Velocimeter(ADV) in the laboratory. The flow was driven by the rotation of the inner cylinder in a way designed not to interfere with flocculation of cohesive sediments. The effect of the inner cylinder for the longitudinal velocities showed highest near the moving boundary and decreased towards the outer wall. At the lower longitudinal velocity, there was a peak in turbulent kinetic energy near the bed, whereas it moved upward to with increasing of the velocity. The longitudinal velocities estimated using the power law were in good agreement with the measured values than the values predicted by the log-law with roughness lengths. The average friction velocities evaluated by Reynolds shear stress were smaller than the values calculated using the log-law and power law when increasing the longitudinal velocity.

Study Case on the Log Cultivation of Phellinus baumii for It's High Quality and Large Quantity (고품질 다수확 원목 상황버섯 재배 경영사례 조사)

  • Suh, Gyu-Sun;Chang, Hyun-You;Kim, Soon-Geun
    • Journal of Practical Agriculture & Fisheries Research
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    • v.10 no.1
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    • pp.153-167
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    • 2008
  • High temperature and natural sun light are considered as the core conditions for high quality and large quantity of Phellinus baumii production. However still now on there has been a mistake of excessively cutting off the natural light by spreading the closing nets on the mushroom cultivating house. For an example there are many houses where the closing nets under the roofs be extended to cover the sides of the houses, which way prevents the mushrooms in the houses from receiving sufficient natural sun light and getting the temperature sufficiently to grow so that the quantity and quality of the produced mushrooms are lowered even though the mushrooms can grow in those conditions. In order to avoid this mistake, the closing nets must be placed on the roofs of the houses only without dropping them to cover the sides. Further more when the closing nets are placed triply at the beginning stage of Phellinus baumii's growth in the house, the nets restrain the internal temperature of the house going up and intercept the natural bright light flowing into the house so that the growing tardiness occur to the Phellinus baumii. Therefore the roof only must have been covered by the closing net for 65% cutting off the light until May, and then covered by double folded the net for June, triple folded the net for July and August, double folded the net for September, and the single net for October. When the ventilation in the house has been maintained until the house tightly balloon out through controling lifting force of internal air, the Phellinus baumii can grow well while the bed logs themselves aren't dried out. Marketing is also very much important as well as increasing quality and quantity of Phellinus baumii production.

Joint Characteristics in Sedimentary Rocks of Gyeongsang Supergroup (경상누층군 퇴적암의 절리 특성 연구)

  • Chang, Tae-Woo;Son, Byeong-Kook
    • The Journal of Engineering Geology
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    • v.19 no.3
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    • pp.351-363
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    • 2009
  • Two orthogonal joint sets develop well only in sandstone beds in the sandstone-mudstone sequences of Gumi and Dasa outcrops within Cretaceous Gyeongsang Basin. And various joint data are similar in the beds of the same thickness in both outcrops, meaning that the joint sets were homogeneously produced by extensional deformation in the same regional stress field. Most of joints in the sandstone beds are orthogonal to, and confined by bed boundaries, which are believed to be formed by hydrofracturing during consolidation after burial. Two orthogonal joint sets are considered to be almost coeval on the basis of mutual abutting relationship which makes up fracture grid-lock and a product of rapid switching of ${\sigma}_2$ and ${\sigma}_3$ axes with constant ${\sigma}_1$ direction oriented to vertical. The joint sets in the sandstone beds show planar surfaces, parallel orientations and regular spacing, with joint spacing linearly proportional to bed thickness. The spacing distributions of the joints seem to correspond to log-normal to almost normal distribution in most of the beds. But multilayer joints do not display regular spacing and dominant size. Either joint set in this study is characterized by a high level of joint density and a saturated spacing distribution as indicated by the mode/mean ratio values and the Cv(coefficient of variance) values. Joint aperture tends to increase with the vertical length of the joints controlled by bed thickness.

A Studyon the Movment of Ground Water of Banayweol Formation (반야월층(半夜月層)의 지하수운동(地下水運動)에 관(關)한 연구(硏究))

  • Kim, Yong Ki
    • Economic and Environmental Geology
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    • v.9 no.4
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    • pp.225-240
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    • 1976
  • This study deals with the flow of bed rock ground water of Banyaweol Formation, which is presently cleared up as a laminar flow. The result obtained may be summarized as the following. 1) The Banyaweol Formation consists mainly of thin-bedded, green to blackish green shale, mudstone, and marl. The marl and mudstone alternatively occur with shale. The marl and mudstone form a aquifer of Banyaweol Formation. In this study, a group of aquifer is in convenience named as a aquifer zone. The aquifer occurs in lenticular form. The aquifer seems to be a type of artesian aquifer because it is covered with aquicludes, but it actually forms a unconfined aquifer because its piezometric surface stays under the lower aquiclude. The lowering of piezometric level is formed because of leakage of the ground water to the lower aquifer undersaturated. 2) The coefficient of permeability of Banyaweol Formation's ground water body (K) is derived by using Dupuit's equation as the following ${\log}K=\frac{CK^2-dK+f}{aK-b}\;\(M=1.365(2H-s)s\\M={\log}1.956s{\sqrt{H}}r\)$ here, $$a=\sum_{1}M_iG_i$$ $$b={\frac{1}{2}log{\sum_{i}}Q_i{^2}$$ $$c=2{\sum_{i}}M_i{^2}$$ $$d=loge{\sum_{i}}M_{i}Q_{i}+2{{\sum_{i}}N_{i}Q_{i}$$ $$f=loge{\sum_{i}}Q_i{^2}N_i$$ If the measured values substituted for the above equation, the coefficient of permeability of the aquifer is 4.1m/day. The coefficient of storge of the aquifer is $2.8{\times}10^{-4}$ if the measured values substituted for Theis's equation. Using the above constants, the filtration velocity of the aquifer is $2.1{\times}1O^{-1}m/day$and the daily flow quantity of the ground water is $847.38m^{3}/day$. 3) In order to understand the time necessary for a circulation of ground water body, the contents of tritum contained in the ground water are measured as 2.3 T.U. at the Korea Atomic Energy Research Institute. Before 1952, the average concentration of tritium per year in groundwater was reported as 10T. u., taking it as the standard, the groundwater of the present study 26.25 years old. Therofore, the groundwater of the Banyaweol Formation is judged as an relatively old groundwater. It is characteristic that the ground water of Banyawol Formation is laminar flow as well as unconfined aquifer and ground water flow of relatively long time. 4) The nature, means of flow, and circulation of Banyaweol Formation's ground water body make it possible set up this ground water body as a ground water system.

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Mycelial growth of some edible mushroom isolates on the media using sawdust from the shiitake waste logs (표고 폐골목 톱밥 배지에서 몇가지 식용버섯균의 균사생장)

  • Seo, G.S.;Lee, B.S.;Lee, J.S.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.9 no.1
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    • pp.33-46
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    • 2007
  • We conducted this research to develop the medium for some edible mushroom cultivation using shiitake waste log which is abandoned after cultivation of shiitake mushroom because those bed logs can not be recycled. The isolates of P. ostreatus(POS-012), P. eryngii(PER-005), G. frondosa(GFR-001) and F. velutipes(FVE-001) were selected and examined for mycelial growth on sawdust media prepared from shiitake waste log. Mycelial growth of selected isolate were satisfactory on the sawdust extract media using acasia(Robinia pseudo-acacia), neutinamu(Zelkova serrata) and kangchamnamu(sangsuri, Quercus acutissima) which are no shiitake-inoculated. Although the mycelial growth of the isolate were poor on the sawdust media prepared from Quercus spp., sawdust of neutinamu, (Zelkova serrata), beotnamu, (Prunus serrulata), orinamu(Alnus japonica), eunsuweonsasinamu(Populus tomentiglandulosa) and chestnut(Castanea crenata) were excellent for mycelial growth. However, shiitake logs which are infected with harmful fungi such as Hypocrea spp. were useful as recycle materials for mushroom cultivation.

Dehydration of Solid Food Material Immersed in Fluidized-Bed (유동층(流動層)에 의한 고체식품(固體食品)의 건조(乾燥))

  • Yu, Ju-Hyun;Lee, Shin-Young;Pyun, Yu-Ryang;Yang, Ryung
    • Korean Journal of Food Science and Technology
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    • v.10 no.4
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    • pp.398-403
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    • 1978
  • Squid was dried on the fluidized-bed in the drying chamber filled with solid particles which were also fluidized with hot-air, and effects of the fluidized particles, the squid's height from the grid and the drying temperature on the drying rate and quality of the squid were observed The mechanism of moisture transfer during the falling rate period was also derived. 1. Sodium chloride was found to be the most suitable fluidized particles and at an air velocity of 3.8 m/sec, optimal fluidization state of this particle was obtained. 2. Uniform profiles of temperature were obtained at a point 4 cm above the grid and the location of squid on the fluidized-bed observed to be suitable when it was 4 cm above the grid. 3. At an air velocity of 3.8 m/sec and when the location height of the squid on the fluidized-bed was 4 cm, the optimal temperature for the drying time which is required to reduce the moisture from 80.8% to 18-22% was 8.5 hours. 4. Drying data followed the empirical equation of unsteady state diffusion $log\;(\frac{W-We}{Wc-We})=-m{\theta}$ in the region of the moisture contents measured and the drying constant (m) was calculated as $0.32hr^{-1}$. These results suggested that the migration of moisture during the falling rate period is due to a diffusion type mechanism. 5. The short constant rate period was observed in the early stage and thereafter, drying was controlled by the falling rate period, and the time ratio of the fluidized bed drying to the through circulation drying for reducing the squid's moisture contents to the same level at the same drying temperature was 1 : 1.4 6. Comparisons of fluidized-bed dried squid and sun dried squid in sale showed that there was no significant change in qualities such as external appearance and hydrogen ion concentration of dry product.

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N-Acyl Amino Acids Surfactant(14) Kinetics for Micelle Formation of sodium N-Acyl Sarcosinate Solution (N-아실아미노산계 계면활성제(제14보) Soium N-Acyl Sarcosinate 미셀형성에 있어 동력학적 고찰)

  • Kim, Myung-Soo;Kim, Hong-Soo;Jeong, Hwan-Kyeong;Nam, Ki-Dae
    • Journal of the Korean Applied Science and Technology
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    • v.17 no.2
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    • pp.105-112
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    • 2000
  • Surface tension as a function of concentration and temperature was measured for aquous solution of sodium N-acyl sarcosinate, $RCON(CH_{3})CH_{2}$ COONa, From the intersection points in the (${\gamma}-logC$) curves, the critical micelle concentration (cmc) was determined at 20, 30, 40, and $50^{\circ}C$. Structural effects on the cmc maximum and the minimum area per molecule at the aquous solution/air interface were discussed. The free energy, enthalpy, and entropy of micellization and adsorption of surfactant solution also were investigated. Numberous investigators have dealt with sodium N-acyl sarcosinates and their applications as wettings, flooding and reducing agents and as corrosion inhibitors.

Industry-University-Research Collaborative Geoscientific Study in Pocheon area for Groundwater Survey, Part II: Seismic Technology (포천지역 지하수기초조사 산학연공동 탐사 사례연구(II): 탄성파탐사기술)

  • Lee, Doo-Sung;You, Young-June;Yoo, Young-Chul
    • 한국지구물리탐사학회:학술대회논문집
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    • 2005.05a
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    • pp.123-127
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    • 2005
  • Surface refraction and crosswell seismic survey conducted as a part of geoscientific studies applied in an area of ground water reservoir shows that, 1) the average velocity with respect to depth is about 250 m/s for the surface layer (<4m), 2,500 m/s for the weathered formation, and greater than 3,500 m/s for the bed rocks, 2) the depth to the bedrock derived from the seismic studies and the sonic log (17m) is somewhat different from the depth obtained from the core study (25m).

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Evaluation of existing bridges using neural networks

  • Molina, Augusto V.;Chou, Karen C.
    • Structural Engineering and Mechanics
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    • v.13 no.2
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    • pp.187-209
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    • 2002
  • The infrastructure system in the United States has been aging faster than the resource available to restore them. Therefore decision for allocating the resources is based in part on the condition of the structural system. This paper proposes to use neural network to predict the overall rating of the structural system because of the successful applications of neural network to other fields which require a "symptom-diagnostic" type relationship. The goal of this paper is to illustrate the potential of using neural network in civil engineering applications and, particularly, in bridge evaluations. Data collected by the Tennessee Department of Transportation were used as "test bed" for the study. Multi-layer feed forward networks were developed using the Levenberg-Marquardt training algorithm. All the neural networks consisted of at least one hidden layer of neurons. Hyperbolic tangent transfer functions were used in the first hidden layer and log-sigmoid transfer functions were used in the subsequent hidden and output layers. The best performing neural network consisted of three hidden layers. This network contained three neurons in the first hidden layer, two neurons in the second hidden layer and one neuron in the third hidden layer. The neural network performed well based on a target error of 10%. The results of this study indicate that the potential for using neural networks for the evaluation of infrastructure systems is very good.

Unrecorded Fungal Species Isolated from Indoor Air in the Log Bed- and Sawdust Media-based Mushroom Cultivation Houses (원목 및 톱밥배지 버섯 재배사 내 실내 공기서 분리한 미기록 진균 보고)

  • Ahn, Geum Ran;Kim, Ji Eun;Kim, Jun Young;Kim, Seong Hwan
    • The Korean Journal of Mycology
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    • v.46 no.4
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    • pp.495-503
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    • 2018
  • Oak mushroom is cultivated using logs and sawdust media as substrates. In this study, fungi were isolated during a monitoring of indoor air in the oak mushroom cultivation houses located in Cheongyang-gun of Chungnam, Geoje-gun of Gyeongnam, Gumi-si of Gyeongbuk, Jangheung-gun of Jeonnam and Yeoju-si of Gyeongggi-do. Identification of the fungi based on morphology and molecular analysis of the internal transcribed spacer region and 28S rDNA, translation elongation factor translation elongation factor 1 a gene, and ${\beta}-tubulin$ gene revealed that six fungi, Cenangium acuum, Neopestalotiopsis surinamensis, Metarhizium marquandii, Periconia macrospinosa, Trichoderma petersenii, and Trichoderma paratroviride that have not been recorded previously in Korea.