• Title/Summary/Keyword: IT Technique

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Membrane Morphology: Phase Inversion to Electrospinning

  • Chanunpanich N.;Byun Hongsik;Kang Inn-Kyu
    • Membrane Journal
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    • v.15 no.2
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    • pp.85-104
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    • 2005
  • Recently, membrane can be prepared by two methods, phase inversion and electrospinning techniques. Phase inversion technique is a conventional but commercially preparation membrane. The most versatile of preparation in this technique is immersion of the cast film into nonsolvent bath, causing dense top layer with a finger-like pattern in the sub layer membrane. The membrane pore size getting from phase inversion is in the range of micro or submicrometer. As a result, it can be used as microfiltration and ultrafiltration applications. A new technique, electrospinning, is introduced for membrane preparation. Nonwoven nanofibrous mat or nanofibrous membrane is obtained. In this technique, electrostatic charge is introduced to the solution jet, causing a thin fiber with high surface area; hence it can be used in the applications where high surface area-to-volume or length-to-diameter ratios are required. Moreover, the pore size can be controlled by controlling the time of electrospinning. Hence, it can be used as a filter for filtering microparticles as well as nanoparticles.

INVERSE HALFTONING USING KALMANN FILTERING

  • Tanaka, Kenichi;Takagi, Ippei
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2009.01a
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    • pp.487-491
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    • 2009
  • The inverse halftoning is processing to restore the image made binary to former step image. There are smoothing and gaussian filtering in the technique so far. However, there are still a lot of insufficient points in past inverse halftoning. The removal of the noise and the edge enhansment are closely related in inverse halftoning. It is difficult to do both the noise rednctiom and the edge enhansment in high accuracy at the same time in the technique so far. The technique that can achieve both the removal of the noise and the emphasis of Edge at the same time is expected as future tasks. Then, it was tried to apply the Kalmann filtering to inverse halftoning. In the actual experiment, the effectiveness of the application of the Kalmann filtering to inverse halftoning comparing it with the technique so far was shown.

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Real time measurement of an acoustic stream by a visualization technique, PIV (PIV(Particle Imaging Velocimetry)에 의한 음향류의 실시간 가시화 계측)

  • 도덕희
    • Proceedings of the Acoustical Society of Korea Conference
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    • 1998.06c
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    • pp.239-242
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    • 1998
  • A new real time sound field visualization technique is introduced in this study using PIV(Particle Imaging Velocimetry) technique. Small particles of which density is small enough to follow up the air flow are used for sound visualization. When the driving frequency is in the vicinity of the resonance frequency of the simplified 2-dimensional muffler system, an acoustic streaming is shown and of which velocity distribution is obtained through PIV technique. It is experimentally proved that the present technique is able to visualize and quantify the sound field's energy flow.

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A Case Report on the Scoliosis Treated by HyunGa manual Technique. ("현가 수기법"을 이용한 척추 측만증의 치험 1례)

  • Lee, Yong-Seob
    • The Journal of Churna Manual Medicine for Spine and Nerves
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    • v.3 no.1
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    • pp.49-54
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    • 2008
  • This study is designed to evaluate the effect of HyunGa manual technique for the patient with scoliosis. After HyunGa manual technique the results of cobb's angle were improved significantly. It is suggested that HyunGa manual technique might be effective for the patiant with Scoliosis.

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Filtered Randomized Response Technique

  • Choi, Kyoung-Ho
    • Communications for Statistical Applications and Methods
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    • v.13 no.2
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    • pp.319-326
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    • 2006
  • Randomized response technique is a survey technique for eliminating evasive answer bias. This technique is popular in social survey for sensitive issues. In this paper we present a simple and obvious procedure for estimating the population proportion of a sensitive group. Here, we shows the weak point in the method of Kim and Warde (2005). Also, it is found that the proposed procedure is more efficient than the ones of Warner (1965) and Kim and Warde (2005). Lastly we discuss the conditions that the suggested method will be more efficienct.

Types of Overlapping Technique in Contemporary Fashion (현대 패션에 나타난 중첩 기법의 유형과 사례분석)

  • Lim, Ji-Ah;Kim, Min-Ja
    • Journal of the Korean Society of Costume
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    • v.63 no.8
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    • pp.106-124
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    • 2013
  • Compared to traditional fashion design, modern fashion design is used as a means that creates original and multiple types of beauty beyond fixed and standardized concept and form. Overlapping technique is the most suitable means to shed classical, authoritative and conservative form and it enables diverse borrowing and quotation for creation. This study aimed to analyze overlapping techniques that are expressed in art, architecture and fashion to find out its characteristics in the field of fashion. The result of this study is as follows. Based on theories of visual perception and advance research, types of overlapping technique were classified as pile, repetition, penetration and transparency. When comparing overlapping techniques in modern fashion with those of painting and architecture, fashion was distinctive in that it had movement and communicativeness through overlapping of fashion and the human body. Therefore, the overlapping technique has wide application and adaptation and can cause specialty, movability, communicativeness and collectivity, which can arouse psychological inspiration.

FEASIBILITY MAPPING OF GROUND WATER YIELD CHARACTERISTICS USING WEIGHT OF EVIDENCE TECHNIQUE: A CASE STUDY

  • Heo, Seon-Hee;Lee, Ki-Won
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.430-433
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    • 2005
  • In this study, weight of evidence(WOE) technique based on the bayesian method was applied to estimate the groundwater yield characteristics in the Pocheon area in Kyungki-do. The ground water preservation depends on many hydrogeologic factors that include hydrologic data, landuse data, topographic data, geological map and other natural materials, even with man-made things. All these data can be digitally collected and managed by GIS database. In the applied technique of WOE, The prior probabilities were estimated as the factors that affect the yield on lineament, geology, drainage pattern or river system density, landuse and soil. We calculated the value of the Weight W+, W- of each factor and estimated the contrast value of it. Results by the ground water yield characteristic calculations were presented in the form of posterior probability map to the consideration of in-situ samples. It is concluded that this technique is regarded as one of the effective technique for the feasibility mapping related to detection of groundwater bearing zones and its spatial pattern.

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New PWM Technique for Two-Phase Brushless DC Motor Drives

  • Lin, Hai;Kwon, Byung-Il
    • Journal of Electrical Engineering and Technology
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    • v.8 no.5
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    • pp.1107-1115
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    • 2013
  • A new PWM technique for a two-phase BLDC motor fed by a two-phase eight-switch inverter is proposed in this paper. It is well known that a two-phase eight-switch inverter can significantly improve power output compared with a two-phase six-switch inverter in a two-phase motor drive. To drive the two-phase BLDC motor simply and effectively, two normal PWM strategies are investigated to manage speed regulation. However, under the conditions of low speed and light load, especially during the braking process, the current in a short time of one period is near zero, which is a discontinuous waveform every half period. To solve it, a novel PWM technique is investigated to improve the operational performance of normal technique. Using the new PWM scheme, the current continues every half period and the braking performance is improved. The effectiveness of the proposed PWM method is verified through the experiments.

Energy-efficient data transmission technique for wireless sensor networks based on DSC and virtual MIMO

  • Singh, Manish Kumar;Amin, Syed Intekhab
    • ETRI Journal
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    • v.42 no.3
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    • pp.341-350
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    • 2020
  • In a wireless sensor network (WSN), the data transmission technique based on the cooperative multiple-input multiple-output (CMIMO) scheme reduces the energy consumption of sensor nodes quite effectively by utilizing the space-time block coding scheme. However, in networks with high node density, the scheme is ineffective due to the high degree of correlated data. Therefore, to enhance the energy efficiency in high node density WSNs, we implemented the distributed source coding (DSC) with the virtual multiple-input multiple-output (MIMO) data transmission technique in the WSNs. The DSC-MIMO first compresses redundant source data using the DSC and then sends it to a virtual MIMO link. The results reveal that, in the DSC-MIMO scheme, energy consumption is lower than that in the CMIMO technique; it is also lower in the DSC single-input single-output (SISO) scheme, compared to that in the SISO technique at various code rates, compression rates, and training overhead factors. The results also indicate that the energy consumption per bit is directly proportional to the velocity and training overhead factor in all the energy saving schemes.

Interactive Multiobjective Decision Making under Fuzzy Environment (Fuzzy 환경하에서의 상호작용적 다목적 의사결정)

  • 이상완;김재연
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.13 no.22
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    • pp.51-57
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    • 1990
  • A new interactive multiobjective decision making technique, which is called the fuzzy sequential proxy optimization technique, has been proposed. This technique is the revised version the sequential proxy optimization technique that the decision-maker's marginal rates of substitution is interpreted as type of L-R fuzzy numbers. It used to the square of normalized scalar product as the doptimalilry condition. However, this technique ignores the imprecise nature of a decision-maker's judgement of marginal rates of substitution. Also, it have a shortcoming that can be only applied over three objective functions. In this paper, considering the imprecise nature of a decision-maker's judgement, we presents an interactive fuzzy decision-making method on the basis of the decision-maker's MRS presented through the use of five types of membership functions including non-linear functions. FORTRAN programs that run in conversational mode are developed to implement man-machine interactive procedure.

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