• Title/Summary/Keyword: pattern shape

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Groundwater Flow Analysis using Numerical model in Small Basin (소규모유역의 수치모헝을 이응한 지하수 유동해석)

  • 최윤영
    • Journal of Environmental Science International
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    • v.12 no.6
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    • pp.615-626
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    • 2003
  • The applied model for this study area is WINFLOW using mite element method, It is thought that the simulation result by WINFLOW model under the steady flow state reflects well the ground water distribution within the reliability level which shows the error range of 1.1% to 8.0% from the comparison between the computed values and the observed, and analyzed that the constant head distribution is shown along the east-west direction and gentle and stable head gradient along the north-south direction. Ground water of the study area shows stable movement from the south to the stream area, and the particle trace for each location shows relatively linear shape from the upstream to the pumping location while the radius of influence according to the pumping amount shows a significant difference at the down stream area from the pumping location. The simultaneous pumping from P and P1 shows more complicated appearance, not the increase of the radius of influence than pumping from a single well P or P1, and it is analyzed that the particle path takes nearly linear form. It is known that the flow direction of the ground water and the velocity of the flow affect on the magnitude of the radius of influence of the wells from the fact that the more decreasing pattern of the ground water head is observed at the side of the well and the down stream area than the upstream area when the ground water moves from south to north regarding the radius of influence according to the pumping amount. Satisfactory results in analyses of ground water movement are obtained through the significant reduction of the physical uncertainties in the flow system as well as the relatively convenient model application using WINFLOW model which is proposed in this study.

Design of Diversity Vehicle Antennas for FM Radio Reception (FM 라디오 수신을 위한 차량용 다이버시티 안테나 설계)

  • Ahn, Seung-Beom;Noh, Young-Ho;Oh, Jung-Hoon;Choo, Ho-Sung
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.20 no.8
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    • pp.761-769
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    • 2009
  • In this paper, we report on the channel capacity and diversity gain of the vehicle on-glass antenna for FM radio reception. The correlation coefficient and channel capacity were obtained using the simulated 3D radiation pattern of each antenna and the Rayleigh channel model for urban environment. To examine the channel capacity we used two antennas which are a simple straight antenna and L-type antenna. Then we observed the available channel capacity by varying the position of feeds and the shape of the L-type antenna. The sample antenna, which has a maximum feed distance with different polarizations, was built and the receiving performance was measured in the weak FM field area. From the results we confirmed that the distance between the feeds should be placed as far as possible for the high channel capacity. If the distance between the feeds are greater than a certain threshold value than the polarizations of the two antennas are getting more important for determining the channel capacity.

Compact Dual-Band MIMO Antenna with High Isolation Performance (소형 고 격리도 듀얼 밴드 MIMO 안테나)

  • Yeom, In-Su;Jung, Chang-Won
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.21 no.8
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    • pp.865-871
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    • 2010
  • A compact dual-band(IEEE 802.11b: 2.4~2.5 GHz, 11a: 5.15~5.825 GHz) 2-channel MIMO antenna for PMP applications is presented. The proposed antenna is composed of a planar inverted F-shape antenna(PIFA) operating at 2 GHz band and a loop antenna operating at 5 GHz band. The proposed antenna is orthogonally arranged at the edge of the ground plane for polarization and pattern diversities with excellent isolation characteristics. The two PIFA antennas operating 2 GHz have connecting line($\lambda_g$/4) face to the feed point for high isolation and low correlation at 2 GHz band. The two loop antennas connected each other in the bottom side to improve the isolation at 5 GHz band. The proposed antenna has a sufficient gain in WLAN service band and is compact sized for the portable media player (PMP) applications.

The Study on the improvement plan for Military combat power by the future computer (미래형컴퓨터를 이용한 군전투력 발전방안 연구)

  • Heo, Yeong Dae
    • Convergence Security Journal
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    • v.13 no.5
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    • pp.57-66
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    • 2013
  • Predicting pattern of future combat ensures a successful war. It is possible to anticipate the shape of the future combat from the fighting method of US Army in the Iraq War. The fighting method: a series of combat progress by real time information to pinpoint strike using a guided weapon by GPS, an intelligence satellite and unmanned surveillance vehicle (USV), shows that real time unification combat power is key element for decide outcome of a war. The NCW is an organically connected network centric warfare paradigm by networking a factor of operation. In this paper, studied on the improvement plan for combat power by the future computer like a portable computer, an audio-recognized computer and non-keyboard computer. In addition, this paper attempts to establish a comprehensive intelligence network of Korea Marine Corps and to apply to combat or training.

A Study on the Costume Culture of Xiongnu (흉노(匈奴)의 복식문화에 관한 연구)

  • Kim, Yong-Mun
    • Journal of the Korean Society of Costume
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    • v.63 no.3
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    • pp.1-16
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    • 2013
  • Xiognu people were the first of the Central-Asian nomads to establish a nation in 209 B.C. They always moved around looking for places to breed their animals and fertile grounds, so they wore clothes made of fur and leather and covered their tents with felt from the livestock. This research studies on the literatures, costumes and the achievement of archaeological excavation. Furthermore, to investigate on costumes excavated of Xiongnu, we visited the Mongolian National Museum and the Hermitage Museum. A corn-hat made of felt, a felt hat with ear flaps and a golden crown with a bird on the top were unearthed from a tomb of Xiongnu in Inner mongolia. Women usually wore pigtails, and men wore pigtails or ponytails but they cut their hair short when holding a funeral. Many pigtails discovered in Noyon uul tombs can be considered as their funeral customs. The Xiongnu wore a round or v-neck caftan attached straight sleeves reaching knees in the left folded style, and because they always rode horses, having the length of the caftan not go past their buttocks would have made it more convenient for them. During the period of Western Han, Ho refered to Xiongnu and it became a common name for northern races. They used leather belts and an animal-designed buckle was found. Women commonly rouged their cheeks for a vivid and cute look, and many ornaments were excavated including bracelets, rings and decorations made of gold, silver, copper and jade, among which there were hair ornaments used to identify one's class. A horse pattern with wings and a horn of Golmod T20 was substitution for the Schythian use of deer. Patterns or shape of unearthed articles present in the Xiongnu culture in Noyon uul had a close relationship with Altaic, Greek and Persian cultures. The Xiongnu clothing was made of animals' skin and fur, woolen textiles and felt. It was folded to the left for upper garments, and the pants were adjusted using a belt and shoes were made of leather, which was very suitable for protection against the cold and horse riding. Mobility played a significant role in their clothing.

Impact Damage of Honeycomb Sandwich Antenna Structures (통신 안테나용 허니콤 샌드위치 구조물의 충격 손상에 관한 연구)

  • Kim, Cha-Gyeom;Lee, Ra-Mi;Park, Hyeon-Cheol;Hwang, Un-Bong;Park, Wi-Sang
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.26 no.2
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    • pp.387-398
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    • 2002
  • The impact response and damage of CLAS panel was investigated experimentally. The facesheet material used was RO4003 woven-glass hydrocarbon/ceramic and the core material was Nomex honeycomb with a cell size of 3.2mm and a density of 96 kg/㎥. The shield plane used was RO4003 and 2024-T3 aluminum. Static indentation and impact test was conducted to characterize the type and extent of the damage observed in two CLAS panels, and the performance of antenna used in a wireless LAN system. Correlation of peak contact force, residual indentation and the delamination area shows impact damage of the panel with an aluminum shield plane is larger than that of the panel with RO4003 shield plane, although the former is more penetration resistant. The damage was observed by naked eye, ultrasonic inspection and cross sectioning. The shape and size of delamination was estimated by ultrasonic inspection, and the area of delamination linearly increases as impact energy increases. The performance of impact damaged antenna was estimated by measuring return loss and radiation pattern. It was revealed that the performance of antenna was related to the impact damage and there was a threshold that the performance of antenna fell as impact energy level changed. The threshold was between the impact energies of 1.5J and 1.75J.

Artificial Spawning Behavior and Development of Eggs, Larvae and Juveniles of the Red Spotted Grouper, Epinephelus akaara in Korea

  • Park, Jong Youn;Cho, Jae Kwon;Son, Maeng Hyun;Kim, Kyong Min;Han, Kyeong Ho;Park, Jae Min
    • Development and Reproduction
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    • v.20 no.1
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    • pp.31-40
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    • 2016
  • This study was conducted in order to examine the egg development in red spotted grouper, Epinephelus akaara and the morphological development of its larvae and juveniles, and to obtain data for taxonomic research. This study was conducted in June 2013, and 50 male and female fish were used for the study. One hundred ${\mu}g/kg$ of LHRHa was injected into the body of the fish for inducing spawning, and the fish were kept in a small-sized fish holder ($2{\times}2{\times}2m$). Eggs were colorless transparent free pelagic eggs, 0.71-0.77 mm large (mean $0.74{\pm}0.02mm$, n=30), and had an oil globule. Hatching started within 27 h after fertilization. Pre-larvae that emerged just after hatching were 2.02-2.17 mm in total length (mean $2.10{\pm}0.11mm$), their mouth and anus were not opened yet, and the whole body was covered with a membrane fin. Post-larvae that emerged 15 days post hatching were 3.88-4.07 mm in total length (mean $3.98{\pm}0.13mm$), and had a ventral fin with two rays and a caudal fin with eight rays. Juveniles that were formed at 55 d post hatching, were 31.9-35.2 mm in total length (mean $33.6{\pm}2.33mm$), with red color deposited over the entire body, and black chromophores deposited in a spotted pattern. The number of fin rays, body color, and shape were the same as that in the adult fish.

Effect of Peanut Seed Orientation on Germination, Seedling Biomass, and Morphology in an Oak Tree Sawdust Cultivation System

  • Ahn, Junsik;Song, Ilchan;Kim, Dongjae;Lee, Joon Chul;Moon, Sungkwon;Myoung, Sooncheol;Ko, Kisung
    • Horticultural Science & Technology
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    • v.35 no.4
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    • pp.402-409
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    • 2017
  • We performed seed germination tests to investigate the effects of seed sowing orientation on germination viability on peanut (Arachis hypogaea L.) sprouts. Specifically, we assessed the influence of seed sowing orientation on germination rate, seedling weight, and seedling length, as well as the seedling vigor index. The seeds were sown in oak tree sawdust at 3.0 cm depth. Four seed orientations were tested: vertical with the hypocotyl end down, vertical with the hypocotyl end up, horizontal with the hypocotyl end down, and horizontal with the hypocotyl end up. The mean seed germination percentages of the four seed orientations were significantly different (p < 0.01) and ranged from 25 to 91.7%. The vertical orientation with hypocotyl-end-down and hypocotyl-end-up orientations showed the highest (91.7%) and lowest (25%) germination rates, respectively. The vertical orientation with the hypocotyl end down produced the heaviest (4.9 g) seedlings and the longest hypocotyls (4.65 cm). This orientation also produced the longest true leaf + epycotyl (2.15 cm) and had the highest seedling vigor index (197.1). The seedlings had a straight growth pattern, whereas seedlings from seeds sown with the hypocotyl up had an awkward plumular hook shape. Taken together, to produce peanut sprouts, we recommend placing the seeds vertically with the hypocotyl end down because this orientation leads to a high germination rate, high biomass production, and high overall seedling quality.

A Study over Catalytic Behavior Octane Enhancer, TAME Synthesis with Ion Exchange Resin Catalysts (이온교환수지 촉매를 이용한 옥탄가 향상제인 TAME 합성반응의 연구)

  • Park, Jin-Hwa
    • Applied Chemistry for Engineering
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    • v.7 no.5
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    • pp.832-842
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    • 1996
  • TAME synthesis was studied in a fixed bed reactor with 3 different types of exchanged resins i.e, Amberlyst-15, Amberlyst-15(wet) and Amberlyst XN-1010. Amberlyst-15 has highest activity, presumably due to the higher reaction participation of the inner active sites of gel shape microparticular resin structure. The optimum reaction conditions for TAME synthesis were found as follows ; reaction temperature of $135^{\circ}C$, molar ratio(MeOH/I.A.A) of 1.0~4.0 and W/F of 2.0~4.0 gr.-cat. hr/gr.-mole. The cross-linking bond of styrene divinyl benzene was observed at $2{\theta}=20$ in XRD pattern. The DSC analysis showed that the thermal stability was in order of Amberlyst-15>Amberlyst-15(wet)>Amberlyst XN-1010. The apparent activation energies of TAME synthesis reaction with Amberlyst-15, Amberlyst-15(wet) and Amberlyst XN-1010 were 12.36, 12.46 and 14.72 kcal/mole, respectively.

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Comparison of the ICT Adoption Pattern;In the Case of Korea and the U.S.

  • Yang, Kyung-Hoon;Lee, Sang-Gun
    • 한국경영정보학회:학술대회논문집
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    • 2007.06a
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    • pp.545-550
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    • 2007
  • The aim of this paper is to find out whether there is a difference in adopting and/or diffusing the information and communication technology (ICT) between countries. If there is, what are the primary factors that keep some countries from adopting and diffusing ICT while others do? To analyze the above problem, we adopted the Unified Theory of Acceptance and Use of Technology (UTAUT) suggested by Venkatesh et al. (2003), which consists of effort expectancy, performance expectancy and social influence. We also use the innovation diffusion functions, which are known to have the S-shape and are made up of the introduction, growth, maturity and decline phases. We do not, however, consider the decline phase, because the ICT that we are considering is not believed to be in that phase. Therefore, we researched how the three factors affect adoption in the three phases. We selected the cellular phone as the ICT, because it is considered to be the most popularly used ICT and its technology has been developing rapidly. We surveyed the cellular phone adopters in Korea, and the U.S. for 15 years from 1989 to 2003. Korea, and the U.S. represent newly developed and developed countries, respectively. For the data analysis, a survival analysis was used, as it could explain the characteristics of the potential adopters or non-adopters. We found that the ICT diffusion patterns, as well as the ICT diffusion factors, of the two countries were different. Therefore, we believe that the results of our research can be used in building strategies on reducing the digital divide gaps between countries.

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