• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.10
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• pp.2565-2571
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• 2009

In this paper, cycle performance analysis of cascade refrigeration system using $NH_3-CO_2$(R717-R744) is presented to offer the basic design data for the operating parameters of the system. The operating parameters considered in this study include subcooling and superheating degree and condensing and evaporating temperature in the ammonia(R717) high temperature cycle and the carbon dioxide low temperature cycle. The COP of cascade refrigeration system increases with the increasing superheating degree, but decreases with the increasing subcooling degree. The COP of cascade refrigeration system increases with the increasing condensing temperature, but decreases with the increasing evaporating temperature. Therefore, superheating and subcoolng degree, evaporating and condensing temperature of cascade refrigeration system using $NH_3-CO_2$ have an effect on the COP of this system. A multilinear regression analysis was employed in terms of subcooling, superheating, evaporating, condensing, and cascade heat exchanger temperature difference in order to develop mathematical expressions for maximum COP and an optimum evaporating temperature.

• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4291-4296
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• 2011

Gravitational SPLITT fractionation (GSF) provides separation of colloidal particles into two subpopulations in a preparative scale. Conventionally, GSF is carried out in a thin rectangular channel having two inlets and two outlets at the top and bottom of the channel, respectively. And the channel is equipped with two flow-splitters, one between the top and bottom inlets and another between the top and bottom outlets. A large scale splitter-less GSF system had been developed, which was designed to operate in the full feed depletion (FFD) mode. In the FFD mode, there is only one inlet through which the sample is fed, thus preventing the sample dilution. In this study, the effect of the sample-loading (in the unit of g/hr) on the fractionation efficiency (FE, number% of particles in a GSF fraction that have the sizes expected by theory) of the new large scale splitter-less FFD-GSF system was investigated. The system was tested in the sample-loading range of 3.0-12.0 g/hr with polyurethane latex beads (PU) and sea-sediment. It was found that there is an optimum range in the sample-loading for a FFD-GSF separation. It was also found that there is a general tendency of FE decreasing as the concentration of the sample suspension increases.

• Research in Plant Disease
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• v.15 no.2
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• pp.101-105
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• 2009

The biocontrol agent Serratia plymuthica A21-4 was selected and proved as an excellent inhibitor of Phytophthora blight of pepper through in vitro and in vivo experiments in previous studies. To enhance the colonizing density of S. plymuthica A21-4 on plant root and rhizosphere soil, some soil conditions might effect on the colonization of the bacteria were examined. The results obtained from the study indicated that the soils containing more sand were favorable to root colonization of S. plymuthica A21-4. Organic amendment such as 3% maize straw(w/w) was helpful to colonize the bacteria in root and soil. The soil temperature about $20^{\circ}C$, water content around 40%, and soil pH near to neutral or slightly acidic, were optimum condition for the colonization of S. plymuthica A21-4 in the rhizosphere soil and roots of pepper. In addition, existence of indigenous biotic entities was beneficial to the colonization of S. plymuthica A21-4.

• Journal of Oriental Neuropsychiatry
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• v.21 no.3
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• pp.1-18
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• 2010

Objectives : This study was performed to develop a standard instrument of oriental medical evaluation for jing ji and zheng chong. Methods : The advisor committee on this study was organized by 17 neuropsychiatry professors of oriental medical colleges. The items and structure of the instrument were quoted from the instrument of pattern identification for jing ji and zheng chong. We took consultation twice from the advisor committee and we also took additional advices by e-mail. Results : We discriminated between bian-zheng and su-zheng from the answers of the advisor committee. We got the mean weight of each symptom and sign from the answers of the advisor committee. We got the final weight from the combination of the ratio of bian-zheng to the number of all answers of the advisor committee and mean weight. Conclusions : The instrument of oriental medical evaluation for jing ji and zheng chong was developed through experts' discussion. If the validity and reliability of this instrument is confirmed through additional clinical trial, the instrument of oriental medical evaluation for jing ji and zheng chong is expected to be applied to the subsequent research.

• Journal of the Korean Society for Library and Information Science
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• v.28
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• pp.71-81
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• 1995

There are no exact copies or carvings of India's original Buddhist Scripts published in Korea that had been flowed into Japan except those of WanSanJungUiMongSanPuPo(환산정의몽산법어). YaWoonJaKyung (야운자경). KyeChoShimHakInMoon(계초심학인문) PalSimSooHangChang(발심수행장) and MongsanWhaSangPupoRackLock published by a mid-Chosun Dynasty Buddhist monk, YaWoon TaesunSa. Others are the translations by Chinese people. All printings were of woodblock except ChonjimyungYangsoo- RhockChapMoon(천지명양수육잡문) of Inkyng wood printing type. This shows perhaps that the Buddhists were so devout that they spared no effort in their prayers to head for the Paradise. Even the woodblock carver himself took his hard work for granted in his belief and engraved the blocks with all his heart taking his work as God-given task. Or. perhaps they to use wood-block printing as the demand for the Scripts soared. By the way. as the Koryo Dynasty took Buddhism as the state religion, it was natural that the Buddhist Scripts were published at TaeJangToKam (the publishing office) and were much encouraged. It is noteworthy. however, that not a few Buddhist Scripts had been published during the Chosun Dynasty despite its crack-down on Buddhism as the Confucianism was declared as the state principle. The Scripts were even published by such temples as MoonJooSa(문수사), MyoHeeAm(묘희암). SsangbongSa(쌍봉사). PyoHoonSa(표훈사), YooJupSa(유점사), YongJangSa(용장사). and AnShimSa(안심사). The fact that the Scripts were even published by KanKyungToKam(간경부감) leads us to reconsider the traditional way of thinking of the Chosun Dynasty as anti-Buddhist or flunkeyist. The historical fact that a record number of Buddhist publications had been transmitted to Japan - is it accidental? - This issue could well be another subject matter for further research. However, it should be noted that very few of above­mentioned Buddhist Scripts are found in present-day Korea.

• The Journal of Internal Korean Medicine
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• v.12 no.1
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• pp.155-165
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• 1991

On the treatment of C.V.A, I obtain the results through the bibliographic investigation in the method of Chong-Yol-Sa-Hwa as follows ; 1. The method of Chong-Yol-Sa-Hwa on the treatment of CVA. is used for the occation of flaming fire in the heart caused by fire emotions in excess (五志過極), difficiency of Yin, flaming up of excessive in liver and plegm-heat. 2. The representative symptoms which can be used by the method of Chong-Yol-Sa-Hwa are firerishness, redness on face, foul breath, fidgets, angry, high fever, constipation slimy and greasy yellow coat of the tongue, and the pulse shaped on full-rapid (洪數), tautsmaooth and rapid (弦滑血數). 3. The general prescription on the method of Chong-Yol-Sa-Hwa are Bang pung tong sung-San, Yangkyuk-San, Backho-Tang, Sosiho-Tang, Samhwa-Tang, Chibo-Tan and Woohwang chongsim-Hwan on excessive symptom-complex, Yookmichihwang-Tang-Kakam, Samool-Tang-Kakam and Youngyangkak-Tang on insufficency symptom complex. 4. The most frequently dosed medicinal plants are Seok-ko, Chi-mo, Dae-Hwang, Mang-cho, Hwang-kewm, Hwang-back, Chi-ja, Si-ho, Han-Su-Seok, Yong-Tam-Cho, Mok-Tan-Pi and Saeng-Chi-Hwang. 5. The method of chong-Yol-Sa-Hwa might be expressed good medicinal effects adopted on the symptoms or flaming evil fire (火旺) after awakend and ‘Yang’ occlusion of Chung-Chang-Pu (中臟脈) which is accompanied with the method of purgation, break through the plegm, resuscitate and nourishing the Yin.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.9
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• pp.2189-2194
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• 2009

The automatic hot gas by-pass technique is applied to control the capacity of refrigeration and air-conditioning system when operating at part load. In the scheme, the hot gas from the compressor is extracted and injected into the outlet of an evaporator through a hot gas by-pass valve. Thus, In this paper, the hot gas by-pass scheme for CO2 is discussed and analyzed on the basis of mass and energy conservation law. A comparative study of the schemes is performed in terms of the coefficiency of performance (COP) and cooling capacity. The operating parameters considered in this study include compressor efficiency, superheating degree, outlet temperature of gas cooler and evaporating temperature in the R744 vapor compression cycle. The main results were summarized as follows : the superheating degree, outlet temperature and evaporating temperature of R744 vapor compression refrigeration system have an effect on the cooling capacity and COP of this system. With a thorough grasp of these effect, it is necessary to design the compression refrigeration cycle using R744.

• International Area Studies Review
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• v.12 no.2
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• pp.227-250
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• 2008

The purpose of this study is to compare the Korean consumers' global brand preference and purchase intension with Chinese consumers. Based on the literature review, we created structural correlation between consumer ethnocentrism, perceived quality, brand of origin image global brand preference and purchase intension. The survey polled 500 university students in Busan, Korea and Shanghai, China. SPSS ver.15.0과 AMOS ver.7.0 statistical package were used to analysis the questionnaire data. In order to examine the structural correlation between variables we operated structural equation modeling. The results of the study were as follows: in Korean case, perceived quality and brand of origin image had positive effect on global brand preference, but consumer ethnocentrism had no effect on global brand preference. And global brand preference had no effect on purchase intension, either. in Chinese case, perceived quality, brand of origin image had positive effect on global brand preference, but consumer ethnocentrism had no effect on global brand preference. while global brand preference had positive effect on purchase intension.

• Journal of Convergence for Information Technology
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• v.11 no.8
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• pp.1-7
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• 2021

In this paper, a method of extending 1 bit by adding an external device to a parallel interface type Digital-to-Analog conversion(D/A C) circuit is presented. To do this, the principle of the D/A C circuit was examined, and the problems that occur when extending one bit by adding individual devices were analyzed, and a bit extension method of the D/A devices using an OP-Amp. circuit was presented. As the proposed method uses the high-precision characteristics of the OP-Amp., even if an error occurs in the device, only the overall size of the output waveform is affected, and the voltage reversal phenomenon that occurs between each bit does not occur. In order to confirm the effect of the proposed method, an experimental circuit was constructed and the absolute voltage of the output and the relative error were measured. As a result, a voltage error of 0.0756% appeared, confirming that the 0.195% requirement for one bit expansion by adding individual devices was sufficiently satisfied.

• Nuclear Engineering and Technology
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• v.55 no.7
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• pp.2556-2566
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• 2023

A first-principle approach within the framework of density functional theory was employed to study the effect of vacancy defects and fission products (FPs) doping on the mechanical, electronic, and thermodynamic properties of uranium monocarbide (UC). Firstly, the calculated vacancy formation energies confirm that the C vacancy is more stable than the U vacancy. The solution energies indicate that FPs prefer to occupying in U site rather than in C site. Zr, Mo, Th, and Pu atoms tend to directly replace U atom and dissolve into the UC lattice. Besides, the results of the mechanical properties show that U vacancy reduces the compressive and deformation resistance of UC while C vacancy has little effect. The doping of all FPs except He has a repairing effect on the mechanical properties of U_1-xC. In addition, significant modifications are observed in the phonon dispersion curves and partial phonon density of states (PhDOS) of UC_1-x, Zr_xU_1-xC, Mo_xU_1-xC, and Rh_xU_1-xC, including narrow frequency gaps and overlapping phonon modes, which increase the phonon scattering and lead to deterioration of thermal expansion coefficient (α_V) and heat capacity (C_p) of UC predicted by the quasi harmonic approximation (QHA) method.