반경험적 스케일 방법을 사용한 0.35 μm LDD-nMOSFET의 핫 캐리어 현상 억제를 위한 공정설계에 관한 연구

서용진,안태현,이경태 대불대학교 1998 論文集 Vol.4 No.1

This paper grasped trends of hot-corrier and punchthrough phenomena as a variation of some process parameters such as LDD doses (P), spacer lengths, channel doses(BF_(2)) and V_(T) adjusting channel implantation energies using Design Trend Curve(DTC). As the LDD dose increased, hot-carrier phenomena became more severe and punchthrough phenomenon was deteriorated. As increasing channel dose (BF_(2)), hot-carrier phenomenon was aggravated in contrast with punchthrough phenomenon which was improved. The model was proved by two dimensional electrical characteristics including generation of impact ionization rate and distribution of electric field with simulation. It was used to TSUPREM-IV and MEDICI for processing and device simulation, respectively.

제주시 재래상권의 활성화 방안

서현진,김태보 제주대학교 관광산업연구소 2001 産經論集 Vol.15 No.2

효소고정화막과 반투막성질의 PVA적층막 제조 및 산소센서에서의 특성

서종원,김태진,정용섭,윤정원 경북대학교 센서기술연구소 1998 센서技術學術大會論文集 Vol.9 No.1

The oxygen electrode of biosensor needs enzyme immobilized membrane and dialysis membrane for measurement of oxygen concentration, which in solution after enzyme reaction with its substrate. The one-layer PVA laminated CTA/PCL membrane was developed for oxygen electrode of biosensor. Enzymes have immobilized on cellulose triacetate/polycarprolactone membrane by CDI method, and laminated with polyvinyl alcohol, aldehyde and acid. This membrane immobilized with glucose oxidase, ascorbate oxidase, pyruvate oxidase and alcohol oxidase by CDI mehod, and PVA laminated CTA/PCL membrane have been tested with various concentration of substrates of enzymes by use of YSI oxygen sensor. Under 5-10mmol substrates become 0.37-0.83μA(r=0.995) currents, and about 56% of glucose oxidase activity was remained after 8 weeks, others were remained very low. SEM shows smooth surface and tightly attached PVA on enzyme immobilized CTA/PCL membrane.

협동학습이 자연과 학업성취 및 과학태도에 미치는 효과

서승조,백남권,조태호,김용진 晋州敎育大學校 科學敎育硏究所 1999 科學敎育硏究 Vol.25 No.-

The purpose of this study is to manifest the effect of STAD cooperative learning which has not yet been explained in cooperative learning of an elementary school, on the academic achievement in science and science related attitudes. Therefore, in order to achieve that purpose, I established the following issues of study. First: What effect does STAD cooperative learning have on the elementary school students' academic achievement in science? Second: What effect does STAD cooperative learning have on the elementary school students' science related attitudes? The results of the study are as follows. First, while it was proven that the effect of STAD cooperative learning on academic achievement in science had no significant difference in pre·post achievement levels for both the experimental group and the control group, the experimental group showed larger changes in the mean value than control group; it can be inferred that classes to which cooperative learning is applied is more effective than traditional science classes. Second, in regard with the effect of STAD cooperative learnign on science related attitudes, while there was a significant difference between the experimental group and control group in pre examination, there was no significant difference, which means STAD cooperative learning does have effect on science related attitudes. In conclusion, the results of this study manifest that STAD cooperative learning is effective for science related attitudes in elementary school science classes, and assume that it can be effective for academic achievement.

高冷地의 효율적인 土地利用에 관한 硏究

徐大振 진주산업대학교 1972 論文集 Vol.9 No.-

Purpose of Study The major purpose of this study was to find out ownership of agricultural production resources and differences in income level between the tobacco-growing farms and sericulture farms in the mountain area and to find out which crop is more profitable to be planted, tobacco or sericulture. The results obtained are as follows: 1. The average area of crop land per farm was 6.68 tanbo in tobacco farms, 10.24 tanbo in sericulture farms. 2. The average man-equivalents of family labor were 2.47 men in tobacco farms, 3.28 men in sericulture farms. 3. Farm assets per farm were 578,772 won in tobacco farms, 686,060 won in sericulture farms. The value of fixed assets covered about 96.4 per cent of the total asset value in tobacco farms, 93.8 per cent in sericulture farms. 4. Gross farm reciepts per farm was 127,921 won in tobacco farms, 205,775 won in sericulture farms. About 71.3 per cent of the gross farm reciepts was obtained from crop production, about 8.2 per cent from livestock production and about 3.3 per cent from off-farm work in tobacco farms, while sericulture farm, about 66.9 per cent from crop productiom, about 29.2 per cent from livestock production, and 5.6 percent from off farm work in sericulture farms. 5. Farm expenses were 44,040 won in tobacco farms, 35,818 won in sericulture farms, and those for wages and fertilizer was highest in tobacco and sericulture farms. 6. Farm income was 83,881 won in tobacco farms, 169,957 won in sericulture farms. Farm income per tanbo was 12,558 won in tobacco farms, 16,597 won in sericulture farms. Farm income per ME was 33.964 won in tobacco farms, 51,615 won in sericulture farms. 7. Reciepts per dollar expense was 65.5 won in tobacco farms, 82.5 won in sericulture farms. 8. Proportion of cash income to gross farm reciepts was 50.4 per cent in tobacco farms, 56.6 per cent in sericulture farms. And proportion of cash income of tobacco to total reciepts was 20,3 per cent, and 6.9 per cent in sericulture farms. 9. Coefficent of variation of gross receipts per tanbo of the cocoon was higher than that of tobacco, while coefficient of variation of cocoon per box was lower than that of tobacco. 10. It is evident through the study that sericulture farms were enable to cultivate crop land more than tobacco farms did, and also that the possibility to ??. the size of sericulture farms was greater than that of tobacco farms.

N₂O 가스로 열산화된 게이트 산화막의 전기적 특성

김태형,김창일,최현식,장의구,서용진,이철인 중앙대학교 생산공학연구소 1992 생산공학연구소 논문집 Vol.1 No.2

미래의 ULSI 소자의 게이트 산화막으로 이용하기 위하여 N₂O 가스 분위기에서 기존의 전기로를 이용한 실리콘의 열산화에 의해 N₂O 산화막을 형성하였고, MOS 소자를 제작하여 전기적 특성을 고찰하였다. 900℃에서 90분간 산화한 N₂O 산화막의 경우, 플랫밴드 전압(??), 고정전하밀도(??)와 플랫밴드 전압의 변화량(??)은 각각 0.81 [V], ?? [??]와 80∼95[mV]를 나타내었다. N₂O 산화막의 전기전도기구는 저전계 영역에서는 Fowler-Nordheim 터널링, 고전계영역에서는 Poole-Frenkel 방출이 지배적으로 나타났고, 절연파괴전계는 16 [MV/㎝]로 높게 나타났다. 따라서 N₂O 산화로 형성된 게이트 산화막이 ULSI 소자의 게이트 유전체로 응용이 가능하리라 생각된다. In order to applicate gate insulators in future ULSI devices, electrical properties was investigated in MOS device with N₂O oxide grown by thermal oxidation using conventional furnace in N₂O ambient. For the sample oxidized at 900℃ for 90 min, Flatband voltage(??), fixed charge density(??) and shifts of flatband voltage(??) after BTS was obtained 0.81 [V], ?? [??] and 80∼95[mV], respectively. The dominant conduction mechanism of N₂O oxide appeared to be Fowler-Nordheim tunneling in the low electrical field region(4-6 [MV/㎝]) and to be Poole-Frenkel emission in the high electrical field region( 9 [MV/㎝] or above). Dielectrics breakdown fields of N₂O oxide appeared about 16 [MV/㎝]. These results suggest that the N₂O oxides is a promising candidate for ultrathin gate dielectric for MOS ULSI applications.

응급실 내원시 예상치 못한 사망 환자의 예측 인자

김욱진,서정필,정성필,황태식,이한식 대한응급의학회 1998 대한응급의학회지 Vol.9 No.4

Background: Unexpected deaths of the patients at ED are surprising to the medical staffs as well as the families. It may also increase the possibilities of medico-legal problems. This study was conducted to review the unexpected death in ED and find the predictive factors leading patients to unexpected death. Methods: A retrospective study with reviewing available medical records of 183 patients who were expired at Ed of Shinchon Severance Hospital from Mar. 1997 to Feb. 1998 and 103 patients of Youngdong Severance Hospital from Mar. 1996 to Feb. 1998 was done. Analyses were done on 30 variables of physical findings, laboratory results, procedures and therapies. We used univariate analysis such as t-test and x²-test and multiple logistic regression analysis. Results: Of the total 286 deaths in Ed, 153 cases were enrolled in this analysis. The number of unexpected deaths were 76. Age, mental status, fraction of neutrophil count, BUN level, whether endotracheal intubation was done, use of inotropics were the factors with statistical significance on the univariate analysis, but only comatose mentality, endotracheal intubated case, and use of the inotropics were significant on logistic regression analysis. The longer the ED length of stay, the higher the rate of mortality and unexpected death. Conclusion: This result suggest that medical attention is needed on the patients with comatose decreased mental status, endotracheally intubated case and needing inotropic agents to prevent unexpected deaths shortening the ED length of stay may also be a factor for decrease the unexpected death rate.

메조포러스 물질에 담지된 팔라듐 촉매에서 메탄의 연소반응 : 티타니아 담지 효과 Effect of Titania Loading

강태구,김태진,김종호,서 곤 전남대학교 촉매연구소 1998 촉매학술발표회 Vol.- No.15

연소과정에 촉매를 사용하여 연소온도를 낮추고 완전산화시키면, 에너지를 효율적으로 이용할 수 있을 뿐 아니라 질소산화물 생성과 일산화탄소 등 불완전연소 물질을 줄일 수 있어 환경오염 방지 측면에서 매우 바람직하다. 화염이 없는 조건에서 안정적으로 열을 발생시키기 위한 중•저온 연소촉매로 활성이 높은 귀금속 성분을 지지체에 담지시켜 사용한다. 통과 유량이 크고 열 발생량이 많기 때문에, 연소촉매의 지지체는 물질과 열전달이 용이하도록 세공이 크고열적 안정성이 우수하여야 한다. 중간 크기의 세공이 발달되어 있는 메조포러스 물질은 물질전달과 열전달이 용이하다는 점에서 연소반응의 지지체로서 가능성이 높다.

α-Amylase Inhibitor 생산균 Streptomyces sp. AI-118의 분리 및 동정

권태종,서동진 建國大學校 附設 産業技術硏究所 1992 논문집 Vol.17 No.-

a-amylase의 효소작용을 저해하는 물질을 생산하는 균주를 토양에서 분리, 동정하였으며 저해물질 생산의 최적 조건을 검토하였다. 본균을 방선균 종정법에 따라 결과 새로운 균주로 판명되어 Streptomyces sp. AI-118이라고 명명하였다. 본 균주는 탄소원으로 corn starch 3.0%, 질소원으로 soy bean meal 1.0%, 무기염으로 NaCI 0.05%, MnSO₄·4H₂O 0.0001%, CuSO₄·5H₂O 0.0001%를 사용한 배지에서 initial pH 6.0, 30℃ 그리고 배양 72시간일 때 최대의 저해물질을 생산하였다. A microorganism, strain AI-118, capable of producing a new a-amylase inhibitor in culture broth was isolated from soil and identified as Streptomyces sp. on the morphological, cultural and physiological characteristics. The preferable medium composition has been determined to be as follows:3.0% corn starch, 1.0% soy bean meal, 0.05% NaCl, 0.05% K₂HPO₄, 0.0001%MnSO₄· 4H₂O and 0.0001% CuSO₄·5H₂O(pH6.0). The inhibitor was maximally produced after 60-80hr cultivation in a jar fermentor at 30℃.

유도결합 플라즈마를 이용한 PZT 박막 식각특성에 관한 연구

안태현,김창일,서용진,장의구 중앙대학교 기술과학연구소 1999 기술과학연구소 논문집 Vol.29 No.-

졸-겔 법을 통해 PZT 박막을 2500 Å을 정착하였고 열처리를 통해 페로브스카이트 상을 얻었다. ICP 장비를 이용하여 Ar(20)/??/?? 가스 조합에 따른 플라즈마에서 기판 온도를 변화시키면서 PZT식각을 수행하였다. 가스 조건으로는 Ar/??:20/80, 기판온도는 80℃, 소오스 파워 500 W, dc 바이어스 전압은 -300 V, 반응로 압력 200 mTorr에서 PZT대 TR과 Pt의 식각 선택비는 각각 0.9, 3.9를 각각 얻었고, PZT 식각속도는 2450 A/min을 얻었다. ?? 가스는 상온에서 응결하므로 공정 반응로까지 이어지는 가스관에 정온 코일을 감아주기 때문에 가판온도을 올리기 전에 이미 데워져 있기 때문으로 여겨진다. 그러나 식각속도는 증가하였다. 이는 B와 BCl의 라디칼이 O와 결합하여?? 그리고/또는 ??의 휘발생 물질을 생성하여 metallic Pb, Zr, Ti가 표면으로 많이 노출되어 Cl 라디칼과 결합이 용이하기 때문에 식각속도가 증가한다고 판단된다. 또한 /?? 가스조건과 80°이상의 식각 프로파일을 얻었다. In this study, PZT etching was performed using plannar inductively coupled Ar(20)/??/?? plasma. The etch rate of PZT film was 2450 Å/min at Ar/?? gas mixing ratio and substrate temperature of 80℃. As increasing content of ??, the selectivities of PZT to Pr and PR increase linearly, and are directly proportional to substrate temperature in less than amount of 50% ??. However, at the condition over 50% ??, the etch rate of PZT have no dependence on the substrate temperature. The selectivities of PZT to Pt and PR were 3.9 and 0.9, respectively at the Ar(20)/??(80) gas mixing ratio and the substrate temperature of 80℃. X-ray photoelectron spectroscopy (XPS) analysis for film composition of etched PZT surface was utilized. The chemical bond of PbO is broken by ion bombardment and Cl radical, and the peak of metal Pb in a Pb 4f narrow can begins to appear upon etching. As increasing additive ?? content, the relative content of oxygen decreases rapidly, in contrast with etch rate of PZT thin film. So, we thought content of oxygen decreases rapidly, in contrast with etch rate of PZT thin film. So, we thought content of oxygen decreases rapidly, in contrast with etch rate of PZT thin film increased because abundant B and BCl radicals made volatile oxy-compound such as ?? and/or ?? bond. To understand etching mechanism, Langmuir probe and optical emission spectroscopy (OES) analysis were utilized for plasma diagnostic.