• JSTS:Journal of Semiconductor Technology and Science
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• v.5 no.2
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• pp.83-88
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• 2005

The interface-states between the top silicon layer and buried oxide layer of nano-SOI substrate were developed. Also, the effects of thermal treatment processes on the interface-state distributions were investigated for the first time by using pseudo-MOSFETs. We found that the interface-state distributions were strongly influenced by the thermal treatment processes. The interface-states were generated by the rapid thermal annealing (RTA) process. Increasing the RTA temperature over $800^{\circ}C$, the interface-state density considerably increased. Especially, a peak of interface-states distribution that contributes a hump phenomenon of subthreshold curve in the inversion mode operation of pseudo-MOSFETs was observed at the conduction band side of the energy gap, hut it was not observed in the accumulation mode operation. On the other hand, the increased interface-state density by the RTA process was effectively reduced by the relatively low temperature annealing process in a conventional thermal annealing (CTA) process.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.10a
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• pp.237-239
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• 2003

A high-temperature superconductor (HTS) journal bearing was studied for loss. Two HTS bearings support the rotor at top and bottom. The rotor weight is 4 kg and the length is about 300 mm. Both the top and bottom bearings have two permanent magnet (PM) rings with an iron pole piece separating them. Each HTS journal bearing is composed of six pieces of superconductor blocks of size 35$\times$25$\times$10 mm. The HTS blocks are encased in a cryochamber through which liquid nitrogen flows. The inner spool of the cryochamber is made from G-10 to reduce eddy current loss, and the rest of the cryochamber is stainless steel. The magnetic field from the PM rings ＜ 10 mT on the stainless part. The rotational drag was measured over the same speed range. Results indicate that the 10 mT design criteria for magnetic field on the stainless part of the cryochamber is too high.

• International Commerce and Information Review
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• v.12 no.4
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• pp.49-65
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• 2010

We have analyzed the trade effect of Korea-EU FTA on the Korean fishery sector, after reviewing the trade pattern and the tariff barriers of fishery sector between Korea-EU. For the trade effects, we have categorized into three cases: 1) the complete tariff elimination of all items, 2) the half tariff reduction on top ten valued items, with complete tariff elimination of other items, and 3) the complete tariff elimination, except unbinding top three valued items. The effect of the complete tariff elimination of all items implies the effect of the full achievement of FTA. For other two cases, these effects imply the effects of the transitional phenomenon of FTA since the complete tariff elimination happens gradually over more than ten years. For the complete elimination of tariff, we found that imports are increased by 1.1 billion dollars which is 12.9% increase in average imports during years 2006-2009. Also, exports are increased by 1.3 billion dollars which is 14.5% increase in average exports during same years.

• Korean Journal of Oriental Medicine
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• v.1 no.1
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• pp.335-345
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• 1995

The clinical study was done as apreliminary to treat Rhinitis with orinetal medicine. We analysed 73 patients with sneezing, nasal discharge and nasal obstruction, who had visited Kept. of Internal Medicine. Hospital of Oriental Medicine, Dongui University from Jan, 1, 1993 to Dec, 31, 1993. The result swere obtained as follows. 1. In the sex ratio, man was higher than woman as 2.31:1 and in age distribution, below 10s was the top as 30.14% 2. In duration of hestory, over one year was the top as 64.38% 3. The most complained symptoms were nasal discharge and nasal obstruction as 94.52% 4. In the frequency of treatments, the cooler season was more than the warmer season 5. In the treatments of Medi-acupunctrer, most of acupuncture therapy was oden less than 5 times and Seonotanggami was most rsed in presciptions. 6. In the case of applying to Seonotanggami, nasal discharge was the most relieved symptom.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.10a
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• pp.388-395
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• 1999

There occurred a moderate size earthquake of M=5 at Whagae-Myun Hadong-Gun Kyongsangnam-Do of Korea, It caused severe damage to the buildings and other structures is Sang-Gye-Sa a famous and beautiful Buddhist Temple, The 5-story stone pagoda was standing in front of Keumdang. The top component tipped over and fell to the ground during the earthquake. In order to have accurate and quantitative estimate of the intensity of earthquake a full-scale replica is made through rigorous verification process, The completed model was mounted on the shaking table and subjected to th seismic tests. It was observed that the top component overturned at 0.16 G of EPGA when the NS component of the 1940 el Centro earthquake records was used as the input motion. A brief history of this project is presented and important test results are report6ed and their implication is discussed.

• Structural Engineering and Mechanics
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• v.26 no.3
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• pp.297-313
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• 2007

A preliminary performance-based seismic design methodology is proposed. The top yield displacement of the system is computed from these of the components, which are assumed constant. Besides, a simple procedure to evaluate the top yield displacement of frames is developed. Seismic demands are represented in the form of yield point spectra. The methodology is general, conceptually transparent, uses simple calculations based on first principles and is applicable to asymmetric systems. To consider a specific situation two earthquake levels, occasional and rare are considered. The advantage of an arbitrary assignment of strength to the different components to reduce eccentricities and improved the torsional response of the system is addressed. The methodology is applied to an asymmetric five story building, and the results are verified by push-over analysis and non linear dynamic analysis.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.4
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• pp.10-17
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• 2001

The performance of a radiator is generally determined using a wind tunnel, in which the air velocity is uniform. However, when it is installed in a car, the distribution of the air velocity becomes nonuniform due to front-end openings, cross members, and horns etc., resulting in lower performance. In this study, several underhood flow simulations have been first performed to get flow rates and velocity distributions over the radiator. Secondly heat release rates are calculated by both a performance curve and a radiator model. Finally, using an engine cooling system simulator, radiator-top-tank temperature is predicted and the variations of heat release rate and radiator-top-tank temperature with nonuniformity of air velocity distributions are analyzed. The results show that the current engine cooling model successfully accounts for the nonuniformity effects that should be considered for higher accuracy in predicting engine cooling performance.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.31 no.4
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• pp.451-460
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• 2007

The surface of 3D shell structure is created by using NURBS and nodes for generating finite element mesh on the surface are created by using external node offset method. In so doing the shortest distance between nodes on the top and bottom surface is searched and then the coordinates of nodes are determined by calculating the mid point of them in the middle of top and bottom surface. Triangular elements are formed on mid surface, and the average aspect ratio of the generated triangular elements are over 0.9.

• Journal of information and communication convergence engineering
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• v.9 no.1
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• pp.74-77
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• 2011

PSPICE modeling of a commercial LED driver IC (TOP245P) and PC817A optocoupler is proposed for the switch-mode power supply (SMPS) (applicable to LED driver) design and simulation. An analog behavioral model of the TOP245P IC including the shunt regulator, under-voltage(UV) detection, over-voltage(OV) shut-down and SR flip-flop is developed by using PSPICE. The empirical equation of PC817A current transfer ratio (CTR) is fitted from the datasheet of PC817A. Two types of SMPSs are simulated with the averaged-model and switching-model. The simulation results by the proposed PSPICE models are in good agreement with those in the data sheet and an experimental data.

• East Asian Economic Review
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• v.23 no.1
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• pp.89-107
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• 2019

This paper ranks higher education in Korea based upon research productivity in business and economics disciplines. The number of SCI-level journal articles are tabulated using the Web of Science search engine, over the sample period from 1990 to 2016. The league table shows that many private universities dominate top-tier ranks, which is consistent with the school reputations most commonly cited by the general public in Korea. In contrast, many national universities appear in the second-tier, and their scanty performance in business and economics is in sharp contrast with our earlier findings in which national universities performed well in science and engineering fields (Jin and Kim, 2018). In addition, the ranking order in lower-ranked schools is found to be sensitive to a small change in publications, whereas the publication gap among top-tier schools is relatively large. Finally, unlike our general perception, the size of school does not matter for collaborative research. Some policy implications are discussed as a conclusion.