• Korean Journal of Pharmacognosy
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• v.26 no.4
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• pp.323-326
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• 1995

Through bioassay-guided separation of the chemical constituents from the heartwood of Dalbergia odorifera, an 2'-O-methoxyisoliquiritigenin(1) was isolated as cytotoxic principle. 1 showed potent cytotoxic activity against the three kinds of human cancer cell lines (A-549, SK-MEL-2 and SK-OV-3) with similar activity to 5-Fluorouracil.

• The Transactions of the Korean Institute of Power Electronics
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• v.9 no.1
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• pp.81-87
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• 2004

This paper describes a design method of electromagnetic interference (EMI) filter for pulse-width modulation (PWM) inverter-fed AC drives used for home appliances such as washing machine and air conditioner. The generating and coupling mechanisms of the conducted EMI for AC drives are first investigated. The design procedure of the EMI filter based on the EMI separation principle is then presented. Experiments we carried out for the PWM inverter-fed induction motor drive system and it is shown that the results satisfy the EN55014 EMI regulation.

• Proceedings of the KIEE Conference
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• 1997.07b
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• pp.682-684
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• 1997

In the design of nonlinear control systems separation principle does not hold. Moreover even an exponentially decaying disturbances can destabilize a nonlinear system and lead to finite escape time from certain initial conditions. So we present a simple output feedback speed controller of induction motors which is designed to minimize the effects of observation error using the Kanellakopoulos et al's interlaced controller-observer design method. Simulation shows that the proposed controller has desired performance like another complex controllers.

• Proceedings of the Membrane Society of Korea Conference
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• 1995.10a
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• pp.80-93
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• 1995

Membrane Technology, which has been in use for over twenty five years, has established itself as one of the principle separation methods. With improved technology, Reverse Osmosis ("RO") has been applied to large volume water treatment facilities. UF and MF Membrane Technology has, up until recently, been applied to small scale water treatment facilities. The fouling of membrane has restricted the growth of Membrane Technology in Water Treatment. Membrane fouling compound found in water causes the loss of flux across the membrane by absorbing to membrane and plugging their pores. Various methods have been used in the reduction and prevention of membrane fouling. For RO, a conventional pre-treatment system removes the pollutants, preventing the function decline of RO membrane by keeping SDI < 4 as the standard condition of feed water. UF and MF Membrane Technology that must have pre-treatment function within itself, are required to keep its ability not to be influenced by fouling.y fouling.

• Korean Journal of Computational Design and Engineering
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• v.6 no.3
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• pp.193-197
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• 2001

This paper describes the design process of super water-saving toilet bowl system by the theory of inventive problem solving (TRIZ). The physical contradiction in TRIZ is defined far saving water in toilet bowl system with preventing the bad smell from septic tank. The super water-saving toilet bowl system is obtained by using the separation principle in time far resolving the physical contradiction. The real system is made using CAD tools. The consumption of water in the system implemented, is estimated about 3 ιcomparing with 13 ι of that in conventional toilet bowl system.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.4
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• pp.128-138
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• 1998

This paper describes a principle of the conducted noise separator which can separate the conducted noise to the common mode and differential mode(normal mode), and presents the transfer characteristics of the separator designed and manufactured. We separated the conducted noise generated from switched mode converter to the CM and DM conducted noise, and also analyzed the source and path of conducted noise in the converter by the conducted noise separator. Since we could easily get the characteristics of the CM and DM conducted noise by the separator, we could efficiently determine the contermeasures for the reduction of the conducted noise and establish the foundation of the systematic procedure for the design of low pass filter.

• Journal of Advanced Marine Engineering and Technology
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• v.20 no.3
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• pp.101-109
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• 1996

Two-dimensional lid-driven closed flows within square cavity were studied numerically for four Reynolds numbers : $10^4$, 3$\times10^4$, 5$\times10^4$ and 7.5$\times10^4$. A convective difference scheme to maintain the same spatial accurary by irregular grid correction is adopted by applying the interior division principle. Grid number is $80\times80$and its minimum size is about 1/400 of the cavity height. At Re=$10^4$, periodic migration of small eddies appearing in corner separation region and its temporal sinusoidal fluctuation are represented. At three higher Reynolds numbers(3$\times10^4$, 5$\times10^4$ and 7.5$\times10^4$), an organizing structure of four consecutive vorticles at two lower corners is revealed from time-mean flow patterns. But, instantaneous flow characteristics show very random unsteady fluctuation mainly due to the interaction between rotating shed vortices and stationary eddies within the corners.

• Applied Science and Convergence Technology
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• v.27 no.4
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• pp.61-64
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• 2018

The basic principle and concept for hydrogen production via water-splitting process are introduced. In particular, recent research activities and their progress in the photoelectrochemical water-splitting process are investigated. The material perspectives of semiconducting photocatalysts are considered from metal oxides, including titanium oxides, to carbon compounds and perovskites. Various structural configurations, from conventional photoanodes with metal cathodes to tandem and nanostructures, are also studied. The pros and cons of each are described in terms of light absorption, charge separation/photoexcited electron-hole pair recombinations and further solar-to-hydrogen efficiency. In this research, we attempt to provide a broad view of up-to-date research and development as well as, possibly, future directions in the photoelectrochemical water-splitting field.

• Applied Chemistry for Engineering
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• v.34 no.4
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• pp.331-346
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• 2023

Recently, green processes that can be directly used in an energy-efficient and electrified society to achieve carbon neutrality are attracting attention. Existing heat and pressure-based desalination technologies that consume tremendous amounts of energy are no exception, and the growth of next-generation electrochemical-based desalination technologies is remarkable. One of the most representative electrochemical desalination technologies is electrochemical ion separation (EIONS) technology, which includes capacitive desalination (CDI) and battery desalination (BD) technology. In the research field of EIONS, various system applications have been developed to improve system performance, such as capacity and cyclability. However, it is very difficult to understand the meaning and novelty of these applications immediately because there are only a few papers that summarize the research background for domestic readers. Therefore, in this review paper, we aim to describe the technological advances and individual characteristics of each system in clear and specific detail about the latest EIONS research. The driving principle, research background, and strengths and weaknesses of each EIONS system are explained in order. In addition, this paper concluded by suggesting the future development and research direction of EIONS. Researchers who are just beginning out in EIONS research can also benefit from this study because it will help them understand the research trend.

• Journal of the Korean Society of Costume
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• v.50
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• pp.119-128
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• 2000

this study was designed to discuss the pattern of Confucian funeral ceremony and its costumes in Chosun dynasty thereby exploring the ideas and symbolic meanings expressed on them. 1. Male's official mourning dresses were composed of Choieui symbolizing sadness Choisang(최상), Dukun Sangkwan Sujil Yojil Kyodai and mourning stick Female's official mourning dresses consisted of Daersoojangkon and Kaedoo which were of simple kinds as compared to those of males. Duration of wearing mourning dreses was the longest to the death of father husband and eldest son The forms of mouring dresses were one and the same irrespective of the noble and the mean which expressed the sameness of the sorrow full of losting blood relative. Symbol expressed on funeral ceremony costumes were something like "eldestson-oriented" "male-centered" "distinction of the sexes" and "principle of yin and yang" to reinforce vitality to the costumes. 2. In the other funeral ceremony costumes in a royal fami8ly were those Euijangsu in red and blue colors Yeosakon in purple and white colors. Bandsman in Danryung and Guards in Kukonbok Changeui and Hoeui with five colors while the generally of people woere white dress in the ceremony Hoeui with five colors symbolized the principle of Yin and Yang costumes of military uniforms the dignity of the royal family: white dresses grife symbolizing the dignity of a royal family and Confucian sorrow as well 3. Unlike the mouring dresses there were great differences relative to socio-ecpmpomic status in funeral goods for dercoration Soyeo and daeyeo Among the goods the instrument to drive out evil spirites symbolized shamanism the distinction of Soyeo and Daeyeo separation of body and soul; the sculpture of the Lord of Hades and messenger philosophy of buddhistic netherworld: the engraving of blue and yellow dragons in bier and Juksanma the principles of Yin and Yang : elaborate burial accesaries realistic viewpoint of the hereafter.