• Title/Summary/Keyword: Current spreading

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A Study on the Utilization of the Internet Based Electronic Commerce (인터넷을 이용한 전자상거래 활용에 관한 연구)

  • 정기호;손종호;오지환
    • The Journal of Information Systems
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    • v.7 no.1
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    • pp.209-224
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    • 1998
  • The Internet is one of the most noticeable things in the information wave, which is spreading in the whole society. At first, the Internet was mainly used to exchange the information between organizations like universities, institutions and companies, but recently it is widely used as the method for the commerce. Therefore the Internet is recognized as a new strategic tool for the business and electronic commerce(EC) supported by the Internet has become a new type of business in the cyber space. This study is to know the current situation of EC by investigating the effect of the Internet compared with the cost. For this purpose we surveyed 162 Korean companies and analyzed the questionaries collected from them. As a result of the analysis it is shown that the Internet is useful for improving the efficiency of business and advertising the company.

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Effects of nano silver contents on screen printed-etched gate electrodes and electrical characteristics of OTFTs

  • Lee, Mi-Young;Park, Ji-Eun;Song, Chung-Kun
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.917-919
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    • 2009
  • Effects of nano-silver contents(15~50wt%) on screen printed-etched gate electrodes and electrical characteristics of OTFTs were investigated. As Ag contents increased, the screen-printed film was transferred exactly without spreading and obtained the densely-packed layer with a stable and excellent conductivity but, its thickness was increased and surface became rougher. It was found that the leakage current of MIM devices and off-state currents of OTFTs became larger due to poor step coverage of PVP dielectric layer on the thick and rough gate electrodes for nano-Ag inks with Ag contents more than 30wt%.

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A Study on Variation of Counterplan in Harmonics Interference Equipment (고초파 장해기기의 저감 대책의 변화에 관한 연구)

  • 성은하;오무송;이은학;김태성
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.05a
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    • pp.414-417
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    • 1999
  • According to development of power electric technology from industrial field to electronic home appliances, recent SMPS using semiconductor is spread widely. Electric converting instrument uses a sine wave voltage source, namely an usual power source, and it gets a non-sines power source from power source because current flows through one part in waveform of one cycle. This injects higher harmonic source in source part, absorb pollution source. And this cause quality deterioration, durability shortage of electric power instrument, spreading accident of electric solver system, and so on. It can't supply an electric source of good quality in industry, so become an impedimental element in improving productivity and reliance. This study can be used in prediction of hindrance and diagnosis material and intends to suggest a countermeasure about measurement data.

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A study on the Electrical Properties by Electric Field Stimulus of Organic Thin Films (유기박막의 전계자격에 의한 전기 특성에 관한 연구)

  • 조수영;전동규;송진원;김해진;이우선;최영일;이경섭
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.05a
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    • pp.49-52
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    • 1999
  • We studied on the ultra thin DMPC by Langmuir-Blodgett(LB) method. The $\pi$ -A isotherm of the DMPC was measured at the air-water interface varying with the compressing speed and amounts of solutions for spreading. DMPC molecules have one phosphatidylcholine head group and two long alky groups with carbonyl group. Displacement currents generated during the compression of monolayers of DMPC on the surface of water were investigated. The molecular arrangement of deposited films were evaluated by measuring the absorption with the UVspectrometer. And we made structures of metal(Au)/DMPC/Metal(Au) and examined electron through DMPC LB films by means of current-voltage(I-V) measurement .

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Diffractive Optical Element for Noise-reduced Beam Shaping of Multi-array Point Light Source

  • Lee, Jonghyun;Hahn, Joonku;Kim, Hwi
    • Current Optics and Photonics
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    • v.5 no.5
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    • pp.506-513
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    • 2021
  • An arrayed diffractive optical element design for the beam-shaping of a multi-array light source is proposed. This is an essential device for recent optical security and face recognition applications. In practice, we devise a DC noise reduction technique featuring high fabrication error tolerance regarding the multi-array light source diffractive optical elements, as a necessary part of the proposed design method. The spherical diverging illumination leads to DC-conjugate noise spreading. The main idea is tested experimentally, and the multi-array light source diffraction pattern is investigated numerically.

Delta Sigma Modulation of Controller Input Signal for the LED Light Driver (시그마 델타 변조에 의한 LED 드라이버의 입력 콘트롤러 설계)

  • Um, Kee-Hong
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.16 no.2
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    • pp.151-155
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    • 2016
  • In this paper, we present the LED dimming control system by using ADPCM (Adaptive Differential Pulse Code Modulation). This ADPCM apparatus accurately controls the LED current with high resolution reducing the RFI (radio frequency interference) due to the spreading out of the harmonics of current of pulses. Additionally, this makes it easier to increase the accuracy of control operation. This study introduces to make a digitally controlled circuit for controlling LED with high-energy efficient by adopting pulse current to LED. The LED current drive system we designed are two systems, the digitally-controlled unit and analog switching mode power supply unit, can be developed separately. The simulation shows the sigma delta modulation of digital to analog converter's output when the input level is 0.7. From this simulation, the output is approached to accurately 0.15% to target value with 510 pulses.

An Experimental Study on Fire Spreading External Wall of Buildings Using Dry Construction Method (건식공법을 이용한 건축물의 외벽 화재 확산의 실험적 연구)

  • Park, Jung-Woo;Cho, Nam-Wook
    • Fire Science and Engineering
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    • v.32 no.4
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    • pp.75-85
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    • 2018
  • The Grenpell tower fire in England in June of 2016 is a representative example of damage caused by a vertical fire spreading through external insulation. Organic insulation materials, which are widely used in external insulation, have the disadvantage that they have good insulation performance but are vulnerable to fire. Aluminum composite panels are used as exterior wall finishing materials, and plastics used in aluminum are regarded as the cause of vertical fire spread. Due to the steel frame used to secure the aluminum composite panel to the outer wall, a cavity is formed between the outer wall and outer wall finish. When a fire occurs on the outer wall, the flammable outer wall as well as the flame generated from the heat-insulating material spreads vertically through the cavity, resulting in damage to people and property. In Korea, material unit performance tests are carried out by the Ministry of Land, Infrastructure and Transport notice 2015 - 744. However, in the UK, the BS 8414 test is used to measure the vertical fire spreading time on the outer wall in real scale fire tests. In this study, the risk of external wall fire was evaluated in an actual fire by conducting a real scale wall fire test (BS 8414), which was carried out in Europe, using aluminum composite panels of semi-noncombustible materials suitable for current domestic standards. The purpose of this study was to confirm the limitations of material unit evaluation of finishing materials and to confirm the necessity of introducing a system to prevent the spread of outer wall fire through an actual scale fire test.

An Understanding the Opening Style of the West Philippine Basin Through Multibeam High-Resolution Bathymetry (고해상도 다중빔음향측심 지형자료 분석을 통한 서필리핀분지의 진화 연구)

  • Hanjin Choe;Hyeonuk Shin
    • Journal of the Korean earth science society
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    • v.44 no.6
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    • pp.643-654
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    • 2023
  • The West Philippine Basin, an oceanic basin half the size of the Philippine Sea Plate, lies in the western part of the plate and south of the Korean Peninsula on the Eurasian Plate. It subducts beneath the Eurasian Plate and the Philippine Islands bordering the Ryukyu Trench and the Philippine Trench with 25-50% of this basin already consumed. However, the history of the opening of the basin's southern region has been a topic of debate. The non-transform discontinuity formed during the seafloor spreading is similar to the transform fault boundaries normally perpendicular to mid-ocean ridge axes; however, it was created irregularly due to ridge propagations caused by variations of mantle convection attributable to magma supply changes. By analyzing high-resolution multi-beam echo-sounding data, we confirmed that the non-transform discontinuity due to the propagating rift evolved in the entire basin and that the abyssal hill strike direction changed from E-W to NNW-SSE from the fossil spreading center. In the early stage of basin extension, the Amami-Sankaku Basin was rotated 90 degrees clockwise from its current orientation, and it bordered the Palau Basin along the Mindanao Fracture Zone. The Amami-Sankaku Basin separated from the Palau Basin while the spreading of the West Philippine Basin began with a counter-clockwise rotation. This indicates that the non-transform discontinuities formed by a sudden change in magma supply due to the drift of the Philippine Sea Plate and simultaneously with the rapid changes in the spreading direction from ENE-WSW to N-S. The Palau Basin was considered to be the sub-south of the West Philippine Basin, but recent studies have shown that it extends into an independent system. Evidence from sediment layers and crustal thickness hints at the possibility of its existence before the West Philippine Basin opened, although its evolution continues to be debated. We performed a combined analysis using high-resolution multi-beam bathymetry and satellite gravity data to uncover new insights into the evolution of the West Philippine Basin. This information illuminates the complex plate interactions and provides a crucial contribution toward understanding the opening history of the basin and the Philippine Sea Plate.

Study on the Establishment of Barley Cultivation System using the Power Tiller (동력경운기를 중심으로한 맥류재배의 기계화 -관작업체계 확립에 관한 연구)

  • 이영렬;최규홍
    • Journal of Biosystems Engineering
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    • v.3 no.2
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    • pp.22-33
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    • 1978
  • To maintain the self-sufficiency of food production , it is required to improved the productivity and increase the effective utilization of land in the double cropping areas using improved cultivation technology. The following reasons encourage this cours of action because the overlapping rice harvest and barely seeding seasons complete for labour, the lower price of barley makes it financially less attractive to grow and these two facts together are responsible for a decrease in barley being planted in certain more seasonably marginal double cropping areas. Fro these reasons, it is desirable to carry out tests to improve the current cultivation techniques . In this interest , the following studies were carried out in the experimental field located at Banweol-myeon, Whasung-jkun, Gyeonggi-do from October 1977 to July 1978 in order to establish the mechanical method of barley cultivation using the power tiller. The summarized results are as follows. 1. The work performance in the seeding operation using the rotary barley seeder was 68 minutes per 10 ares which compares favourably with 408 min/10a using the conventional method. This is only one sixth of the time required by th conventional method. The operating costs using the rotary barley seeder was 1, 463 won per 10 areas as against 3, 486 Won per 10 ares for the conventional method, showing a saving of about 50% in comparison with the conventional method. 2. In the manure spreading operation, the work performance was 25 min/10a for the manure spreading machine , compared to 1089 min/10a for the manual operations. This is about one fourth of the time required by the conventional method, The operating costs were 810 Won/10a for the machine and 857 Won/10a for the manual labour. This cost shows little advantage by the machine over the manual labor costs. The conventional method of manure spreading will continue pending decision which will develope and improve the machine.3. Work performance in the rolling operation using the barley rolIer was 30 min/lOa which compares favourably with 135 min/10a using conventional method. This was one fourth of the time required by the conventional method. The operating costs were 514 Won/103. for the machine and 1, 003 Won/lOa for manual labour. In the weed control operation, the work performance and operating costs were 45min/lOa, 1, 399won/10a for the herbcide application using the power sprayer, 1, 149min/10a 8, 541won/lOa for the conventional method respectively. This is 26 times higher efficiency in comparison to the conventional method. 4. In the harvesting operation using the reaper binder and tiller attachment, the work performance was 60min/lOa and represents a cost of 2, 039won/10a. The con\ulcornerventional method took 640min/10a at a cost of 4, 757won/lOa. The reaper binder showns a saving of one tenth over the conventional method. The automatic thresher is already recommended for the current situations, and is now being used. 5. From a comparison of the results of the above trials, the serial cultivation system using the attachment for the power tiller such as the rotary barley seeder is now to be recommended for the current barley cultivation system. It is also recommend from these results that the mechanized technology now available must be used to improve and maintain the increase in barley production. It is seen th1t this is the only course now avaihble to solve the peak seasonal requirements of labour needed for l11rvesting and seeding between rice and barley cultivation.

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A Study on the Strategies of the Fashion Industry toward Fast Fashion (패스트 패션(Fast Fashion) 도입에 따른 패션 업계의 대응 전략 연구)

  • Lim, Sung-Min;Choi, Ju-Young;Kim, Mi-Sook
    • The Research Journal of the Costume Culture
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    • v.16 no.3
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    • pp.432-443
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    • 2008
  • Fast fashion is widely accepted in young generation who are eager to the new fashion trends. With the consumers' rapid adoption of fast fashion, fashion retailers have tried to adopt strategies to reflect current and emerging trends as quickly as possible and effectively in current merchandise assortment, raises important issues with respect to the processes of effective merchandise management. However, the concept of fast fashion has not been academically investigated and developed properly yet. Therefore, this study mainly reviewed secondary data such as leading fast fashion companies' website, newspaper articles and Zara's case study which covers fast fashion issues. Fast fashion gets widely spreading in market, current investigation showed that domestic fashion companies have adopted fast fashion concept in early stage. This study tried to examine characteristics and strategies used by fast fashion businesses to provide domestic fashion industry with valuable information of production and marketing strategies. Suggestions through the result are as follows: 1. Fast fashion requires flexible managing systems such as SCM, QRS and JIT in order to promote efficient production and assortment management from the entire supply chain. 2. Domestic fast fashion companies should build up not only quality of good design but also reasonable price and strengthen marketing strategies in order to compete with abroad fashion companies 3. Fashion companies that succeed in satisfying consumer's desire for new trend show that it has been successful their strategy to make market area wider to the world not focusing on domestic market.

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