• Journal of the Korean GEO-environmental Society
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• v.9 no.5
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• pp.83-89
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• 2008

This study is to figure out the speed of soil diffusion and shapes as well when landslide occurred. It was measured the speed and shapes of soil diffusion using installed indoor-simulation of a land slide. Standard sand was used to measure it and this measurement is following the moisture content of standard sand. The result of this experiment follows the moisture content; as the moisture content goes up, the area and speed of soil diffusion goes faster as well. As the average of records by the moisture content was analyzed, the area and speed of land slide are increased proportionally. The shape of diffusion is formed as fanwise. It depends on the moisture content as above; the speed was fast when the moisture content is high, and it was getting narrower and longer as the speed of diffusion was faster.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.7
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• pp.27-37
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• 2003

This study was performed to examine the flowing ability and filling ability of polypropylene fiber reinforced high performance concrete. The slump flow was decreased with increasing the polypropylene fiber content, rapidly. At the box-type filling ability, the difference of box height was increased with increasing the fiber content and the box-type passing ability was closed in fiber content 1 %. The final flowing distance of L-type was decreased with increasing the fiber content. Also, it was decreased above 0.75% of polypropylene fiber content, rapidly. The filling ability of L-type was badly showed above polypropylene fiber content 0.75%. Also, the compressive strength was decreased with increasing the fiber content, but the flexural strength was shown higher than that of the concrete without fiber. At the impact resistance, drop numbers for reaching in final fracture were increased with increasing the fiber content. Also, the drop numbers for reaching initial fracture of 1mm were increased with increasing the fiber content. At the acid resistance, the percent of original mass was decreased with increasing the fiber content.

• Proceedings of the Korean Information Science Society Conference
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• 2012.06d
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• pp.225-226
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• 2012

현재 스마트 장치에는 3G, LTE, Wifi나 Bluetooth를 이용하기 위한 인터페이스들이 동시에 탑재되고 있다. 아울러 다양한 인터페이스를 가지고 있는 장치의 서로 다른 인터페이스를 이용하여 통신 세션을 유지하기 위한 연구인 Flow Mobility에 대한 연구가 활발히 진행 중이다. 또한 다양한 미래 인터넷 연구 주제들 중 하나인 컨텐츠 중심 네트워크에서도, 노드의 이동에 따른 문제점을 해결하기 위한 연구가 진행중이다. 본 논문에서는 컨텐츠 중심 네트워크에 Flow Mobility를 지원하기 위해 Flow Mapping Agent를 제안하고, 노드 이동 시나리오를 통해, 본 논문에서 제안한 기법에 대해 설명하였다.

• Journal of Biosystems Engineering
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• v.25 no.2
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• pp.89-96
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• 2000

In this study, experiments were performed for various drying air temperatures, air flow rates tray distance to analyze drying characteristics of batch type tunnel dryer. In comparison of tunnel drying with cabinet drying which is currently used in the farm, the results of drying simulation model of cabinet dryer was used and then the possibility of applying the drying simulation model of cabinet dryer to batch type tunnel dryer was investigated. The results showed that as the drying temperature increased, the drying rte and moisture difference in the direction of air flow increased and as the air flow rate increased, the drying rate increased and moisture differences decreased. In tunnel dryer, drying through bottom of the tray had large effect on drying rate and the effect was more significant when the drying temperature increased. As air flow rate increased, the difference of drying rates between tunnel and cabinet drying increased and drying rate of tunnel of drying was higher. The drying simulation model could estimate moisture content in tunnel more precisely by using modified effective moisture diffusion coefficient for air flow rate.

• Journal of Electrochemical Science and Technology
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• v.14 no.1
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• pp.38-50
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• 2023

Proton exchange membrane fuel cell (PEMFC) is a portable and clean power generation device. The structural arrangement of the flow field has a significant influence on the delivery efficiency of PEMFC. In this article, a new bionic flow channel is designed based on the inspiration of a spider shape. The branch channel width and branch corner are studied as the focus, and its simulation is carried out by the method of computational fluid dynamics (CFD). The results show that when channel width/rib width and corner of the branch are 1.5 and 130° , respectively, it is the best numerical combination and the cell comprehensive performance is excellent. The final model using this numerical combination is compared with the traditional flow channel model to verify the advancement of this scheme.

• Journal of Welding and Joining
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• v.32 no.6
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• pp.14-21
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• 2014

High-temperature corrosion resistance of martensitic-hardfaced weldment is generally evaluated by the Cr content depending on dilution rate. Present study used a commercial program(SYSWELD) applying three-dimensional heat flow analysis to predict temperature distribution of weld. Configuration of weld bead can be determined by the contour of melting temperature and simultaneously dilution rate is calculated to predict Cr content. Experimental study also has been conducted to measure Cr content of harfaced surface welded by FCAW. Results indicated that computational results were well matched with those obtained from experiments.

• Magazine of the Korean Society of Agricultural Engineers
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• v.40 no.6
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• pp.79-88
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• 1998

This study was conducted to measure the moisture content of soil using RF impedance in the range of 1 to 30MHz. Considering the water potential flow in the soils, two types of sensor such as parallel cylinder and perpendicular plate type were fabricated and tested. The capacitance and resistance of sonsors for soil samples having moisture content range of 2 to 27% were measured by Q-meter (HP4342). The higher soil moisture content was and the larger soil bulk density was, the more the capacitance of sensors increased. To eliminate the effect of bulk density on measuring soil moisture content using RF impedance, two kinds of model having the density independent functions such as the ratio of capacitance change to conductance change and weight of water and dry soils respectively were developed and estimated by regression analysis.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.2
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• pp.128-133
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• 1998

Analyses of now karyotypes using different maize (Zea mays L.) inbred lines have been performed. The accumulation and isolation of high quality and quantity metaphase chromosomes from root tips can be achieved from many kinds of maize lines. The chromosome suspensions were prepared by a simple slicing method from synchronized maize root tips and analyzed with a now cytometry. The variations of experimental now karyotypes were detected among inbred lines in terms of the positions and/or the numbers of chromosome peaks. The 2C DNA amount among 8 inbred lines ranged from 5.09 to 5.52 pg. The variability of DNA content in maize chromosome 1 was 9.1 % ranging from 0.685 to 0.747 pg. The selection of appropriate maize lines is critical for sorting specific single chromosome types. At least five different chromosome types can be discriminated and sorted from five maize lines.

• Journal of Biosystems Engineering
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• v.23 no.1
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• pp.21-30
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• 1998

A theoretical model was developed to evaluate the effects of soil and airflow characteristics on the soil-air heat exchanger performances. The model, which includes three-dimensional transient energy and mass equilibrium-equation, was solved by using a computer program that uses Finite Difference Methods and Gauss-Seidel iteration computation. Energy gains, heat exchange efficiencies, and outlet air temperature are presented including the effects of soil moisture content, soil conductivity, soil thermal diffusivity, and soil initial temperature. Also, data related to the effects of airflow rate and inlet air temperature on the thermal performance of the system are presented. The results indicated that energy gains depend on soil conductivity, soil thermal diffusivity, and soil initial temperature. Heat exchange efficiencies relied on air mass flow rate and soil moisture content.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.04a
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• pp.14-17
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• 1995

This study is designed for producing and analyzing the structure application properties of the ready mixed concrete of specified concrete strength about 400kg/$\textrm{cm}^2$ in the batcher plant. And this part is designed for analyzing to the slump, slump flow, air content and unit weight in fresh state. By the test results of fresh concrete state, the slump, slump flow and air content are decreased, but unit weight is increased while open time is passed.