• Journal of information and communication convergence engineering
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• v.9 no.5
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• pp.583-586
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• 2011

In this paper, subthreshold swing characteristics have been presented for double-gate MOSFETs, using the analytical model based on series form of potential distribution. Subthreshold swing is very important factor for digital devices because of determination of ON and OFF. In general, subthreshold swings have to be under 100mV/dec. The channel length $L_g$ is varied from 30nm to 100nm, and channel thickness $t_{si}$ from 15 to 20nm according to channel length, and oxide thickness 5nm to investigate subthreshold swing. The doping of channel is fixed with $10^{16}cm^{-3}$ p-type. The results show good agreement with numerical simulations, confirming this model.

• Journal of KIISE:Software and Applications
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• v.27 no.9
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• pp.961-972
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• 2000

본 논문에서는 사용자의 적합 피드백을 기반으로 적합 문서들에서 발생하는 용어들과 초기 질의어간의 발생 빈도 유사도 및 퍼지 추론을 이용하여 용어의 가중치를 산정하는 방법에 대하여 제안한다. 피드백 문서들에서 발생하는 용어들 중에서 불용어를 제외한 모든 용어들을 질의어로 확장될 수 있는 후보 용어들로 선택하고, 발생 빈도 유사성을 이용한 초기 질의어-후보 용어의 관련 정도, 용어의 IDF, DF 정보를 퍼지 추론에 적용하여 후보 용어의 초기 질의어에 대한 최종적인 관련 정도를 산정 하였으며, 피드백 문서들에서의 가중치와 관련 정도를 결합하여 후보 용어들의 가중치를 산정 하였다. 본 논문에서는 성능을 평가하기 위하여 KT-set 1.0과 KT-set 2.0을 사용하였으며, 성능의 상대적인 평가를 위하여 Dec-Hi 방법, 용어 분포 유사도를 이용한 방법, 퍼지 추론을 이용한 방법들을 정확률-재현률을 사용하여 평가하였다.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.486-490
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• 2009

In order to investigate the offshore wind resources, the "QuikSCAT Level 3" data by the QuikSCAT satellite was analyzed from Jan 2000 to Dec 2008. QuikSCAT satellite is a specialized device for a microwave scatterometer that measures near-surface wind speed and direction under all weather and cloud conditions. Wind speed measured at 10 m above from the sea surface as extrapolated to the hub height by using the power law model. It has been found that the high wind energy prevailing in the south sea and the east sea of the Korean peninsula. From the limitation of seawater depth for piling the tower and archipelagic environment around the south sea, the west and the south-west sea are favorable to construct the large scale wind farm. Wind map and monthly variation of wind speed are investigate at the positions.

• Journal of Chest Surgery
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• v.15 no.3
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• pp.267-273
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• 1982

We have observed 360 cases of spontaneous pneumothorax from Jan. 1971 to Dec. 1981 at the department of Thoracic and Card iovascular Surgery, Yonsei University College of Medicine. The patients age ranged from 2 days to 95 year-old. The associated pulmonary lesions were shown pulmonary tuberculosis in 158 cases[43.9%], bullae in 35, pulmonary emphysema In 32, pneumothorax in 10, paragonimiasis In 7 and unknown underlying pathology in 109 patients. 70 [51.1 %] out of 1 37 cases who received conservative medical treatment Including thoracentesis were cured completely, but the 67 cases [48.9 %] of remaining uncured patients were treated by surgical procedures. The 290 patients who received surgical management were recovered without recurrent pneumothorax. The surgical procedures were closed thoracotomy drainage or explothoracotomy. The choice of treatment should be based on the extent of pneumothorax or the presence of underlying pulmonary disease. Tube thoracotomywas the most effective procedure in achieving the expansion of collapsed lung. On the other hand, open thoracotomy could be a good approach to recurrent pneumothorax, persistent air leakage, incomplete expansion of the lung and bilateral pneumothorax. The minithoracotomy Is the best procedure to recurrent pneumothorax.

• Journal of Chest Surgery
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• v.13 no.2
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• pp.110-117
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• 1980

This is a case report of total anomalous pulmonary venous drainage with Atrial septal defect, which was corrected surgically by intracardiac procedure under total cardiopulmonary bypass. This 9 years old girl, she complained mild cyanosis, exertional dyspnea, and frequent upper respiratory infection from 3 months age. The chest X-ray showed cardiomegaly and a "snow man appearance", she has systolic murmur with splitting of S2. The diagnosis was confirmed with right heart catheterization, the catheter was reached to right pulmonic vein passed through right atrium, right superior vena cava, innominate vein, left superior vena cava, and common venous trunk. On 28th, Dec. 1979, an anastomosis between common pulmonary venous trunk and left atrium, Pericardial patch closure of ASD, and ligation of left superior vena cava were performed with Extra-corporeal circulation. The postoperative course was uneventful and discharged with excellent general condition.Total Anomalous Pulmonary Venous Drainage with A.S.D. with A.S.D.

• Journal of Chest Surgery
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• v.17 no.3
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• pp.511-515
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• 1984

In this study, 213 cases of the spontaneous pneumothorax experienced at the department of thoracic and cardiovascular surgery, Chungnam National University Hospital during from April, 1977, till Dec, 1983 were reviewed. 1.Sex ratio of the studied patients was 7.19;1 showing high incidence male patients. The incidence according to the age group showed that 20.2%, 18.3% of the patients belong to the age group 6th, 5th decade respectively. 2.The etiologic factors were as follows, tuberculous origin in 50.2%, unknown origin in 28.2%, COPD in 3.3%, bullae in 8.5%. The site was right in 47.9% and left in 44.1%, bilateral in 8%. 3.The clinical symptoms were frequently dyspnea in 35%, chest pain in 27.5%. 4.The employed method of treatment were as follow, bed rest with oxygen inhalation in 1.9%, closed thoracostomy in 95.8%, open thoracotomy in 7.98%, which bullectomy was performed in 12 cases and pneumonectomy in 3 cases and lobectomy in 1 case and decortication with simple closure of bleb was performed in remaining 1 case. 5.The duration of closed thoracostomy was longer in tuberculosis, which average duration was 11.28 days. 6.The overall recurrent rate was 12.3%.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.5
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• pp.587-591
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• 1996

An intercomparison experiment was implemented to assess the uncertainties and precisions om atmospheric SO$_{2}$ measurement techiques including a pulsed fluorescence (P-F), a diffusion-scrubber /ion chromatography (D-I), and a mist-chamber/ion chromatography (M-I). Each of those three techniques was investigated by researchers at Seoul National University, Yonsei University, and Hankuk University of Foreign Studies, respectively. The concentrations of atmospheric SO$_{2}$ were determined concurrently using three independent measurement techniques at the Seoul National University campus, Korea during Nov.22 to Dec.2, 1995. While the results from the P-F and D-I techinques showed the very close agreements (within +-5%) throughout the experiment period, M-I technique showed systematically smaller values (up to 30%) than the other two techniques. Although sources of larger discrepancy between different techniques were mot identified, the lower SO$_{2}$ values of the M-I method may be related to the errors associated with sample collection effciency, mass flow rate measurements, and standardization of ion chromatography.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.5
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• pp.503-513
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• 2003

A single particle analytical technique, called low-Z electron probe X-ray microanalysis (low-Z EPMA) was applied to characterize atmospheric particles collected in Busan, Korea, over a daytime period in Dec. 2001. The ability to quantitatively analyze the low-Z elements, such as C, N, and 0, in microscopic volume enables the low-Z EPMA to specify the chemical composition of individual atmospheric particle. Various types of atmospheric particles such as organics, carbon-rich, aluminosilicates, silicon oxide, calcium carbonate, iron oxide, sodium chloride, sodium nitrate, ammonium sulfate, and titanium oxide were identified. In the sample collected in Busan, sodium nitrate particles produced as a result of the reaction between sea salt and nitrogen oxides in the atmosphere were most abundantly encountered both in the coarse and fine fractions. On the contrary, original sea salt particles were rarely observed. The fact that most of the carbonaceous particles were distributed in the fine fraction implies that their origin is anthropogenic.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2008.10a
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• pp.520-524
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• 2008

This research verifies the phenomenon of which the Momentum and Reversal effect of stock price would depend on the subject of investment in the point of view of the Behavior Finance hypothesis. For the experiment, this paper uses the KOSPI200 daily data and Net Investment Flow from Jan. 1999 to Dec. 2006. And we analyze the marginal profit and loss with foreigners, individual investors, and institutions. We verify the response of the subjects of investment based on the CAR for 3 days after more than 3 percent rising or drop. We also verify the response with respect to the ascending and descending trend based on the profit trend and subjects' behaviors a week before the drop.

• Asian Journal of Atmospheric Environment
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• v.4 no.1
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• pp.20-25
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• 2010

The gaseous $^{222}Rn$ concentration at the level of clouds was estimated by using the wet scavenging model of its decay products with the observed data of environmental radiation at the ground. And the origin of the $^{222}Rn$ was also discussed. The estimation was done for a precipitation event on Dec. 26-27, 2003, when a large increase of the radiation was observed in Tokai-mura in Ibaraki, Japan. From a backward trajectory analysis, the origin of $^{222}Rn$ atoms for that event was traced back to the northeastern part of China, and it was expected that the large amount of $^{222}Rn$ emitted in the northeastern part of China was transported to Tokai-mura by the Eurasian continental air mass.