• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제37권1호
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• pp.15-20
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• 2011

Introduction: The characteristics of oral tongue squamous cell carcinomas (SCC) and the treatment results were reviewed to determine the appropriate treatment strategies. Materials and Methods: The medical records of 140 patients diagnosed and treated for oral tongue SCC at Yonsei University Health System from January 1995 to December 2004 were reviewed. For statistic analysis, the survival rate was determined using the Kaplan-Meier method with SPSS version 12.0, and the difference in survival rates was evaluated using a log-rank test. Results: The mean age of the patients with oral tongue SCC patients was 55 (19-85 years old). According to the T, N and pathologic stage, the patients were distributed from a higher to a lower incidence of cases, as follows: T2 (46.4%), T1 (37.9%), T4 (8.5%), and T3 (7.1%); N0 (65%), N1 (20.7%), N2 (13.6%), and N3 (0.7%); and stage I (31.4%), stage II(25.7%), stage IV (22.2%), and stage III (20.7%). Local and regional recurrence and distant metastasis was present in 13.6%, 5% and 4.2% of patients, respectively. The five-year survival rate was 72.2%, and the prognostic factors for oral tongue SCC included neck metastasis, pathologic stage of the disease, cell differentiation, treatment modality, neck dissection as part of the treatment plan, and neck node recurrence. Discussion: It is suggested that ipsilateral neck dissection or bilateral neck dissection should be selected as a treatment of tongue SCC patients with advanced stage.

• Journal of Microbiology and Biotechnology
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• 제8권2호
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• pp.119-123
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• 1998

The feasibility of using combined treatments of electric field and chemical mutagen N-methyl-N'-nitro-N-nitroso-guanidine (NTG) for the strain improvement of Saccharomyces sp. in ethanol production was examined. The treatment of electric field alone resulted in no effect on the lethality of yeast cells under the conditions of this study. However, when the electric field was applied together to the treatment of yeast cells with NTG, the electric field increased the lethal effect and auxotrophic mutation rate of NTG. The combined treatment of electric field and NTG also increased the chances of. obtaining superior yeast strains for the ethanol production from tapioca. A higher number of improved clones was obtained by the combined treatments of electric field and NTG than by the NTG treatment alone. The best clone, NF 30-9, which was also obtained by the combined treatment, produced $11.07\%$ (w/v) ethanol from tapioca slurry containing 25% (w/v) reducing sugar while the parental strain produced 9.77% (w/v).

• 한방재활의학과학회지
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• 제23권3호
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• pp.125-132
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• 2013

Objectives The purpose of this study was to compare the effects of acupuncture treatment with those of collaborative treatment regarding acute Bell's palsy. Methods Twenty-six patients who received outpatient treatment between March 2012 and February 2013 were divided into 2 groups. The East-West treatment group (EW group, n=12) received prednisolone and then acupuncture afterwards. The Eastern treatment group (E group, n=14) received just acupuncture. Acupuncture was administered 3 to 4 times a week, and both groups were educated to practice facial muscle exercises at home. Evaluations were made before treatment, after 1 week, 2 weeks, and 3 weeks using the House-Brackmann facial nerve grading system. Results Compared to before treatment, the House-Brackmann grades of both EW and E groups after 1, 2 and 3 weeks of treatment significantly decreased (p<0.05). Regarding group comparison, the House-Brackmann grade of the EW group was significantly lower than the E group at 1 week (p=0.043), but there was no significant difference at 2 and 3 weeks. Regarding improvement of House-Brackmann grades, there was no significant difference between the two groups at 1, 2 and 3 weeks (p>0.05). Conclusions Compared to just acupuncture treatment, collaborative treatment with prednisolone significantly improved the House-Brackmann grade after 1 week, but there was no difference as time passed. Because early intervention determines the prognosis of Bell's palsy, collaborative treatment at the early stage will be clinically helpful to patients.

• 열처리공학회지
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• 제10권2호
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• pp.138-149
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• 1997

TiN and AlN are ceramic materials with extensive applications due to its excellent mechanical and chemical properties at elevated temperature. The purpose of this research is to develop the method for the synthesis of ternary nitride powder, titanium-aluminum-nitrogen system, which have an excellent property of both TiN and AlN. The ternary nitride such as $Ti_3AlN$, $Ti_2AlN$ and $Ti_3Al_2N_2$ can be synthesized by the interdiffusion nitriding method in Ar gas, however, the ternary nitride coexist with TiN, AlN, $Ti_3Al$ and ${\alpha}$-Ti. The ternary nitride are stable below $1400^{\circ}C$, but these are gradually decomposed into TiN, $Ti_3Al$ and AlN above $1400^{\circ}C$. The thermal oxidation characteristics of the Ti-Al-N compound synthesized by the interdiffusion nitriding method is superior to that of the TiN+AlN mixed powder, and the oxidation for both materials show the differential behaviors.

• 열처리공학회지
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• 제8권1호
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• pp.32-43
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• 1995

Ti-6Al-4V alloy are widely used in chemical and aircraft industries for their good corrosion resistance and high strength to weight ratio. Surface alloying of Ti alloy by $CO_2$ laser is able to produce few hundred micrometers thick TiN surface-alloyed layer with high hardness on the substrate very simplely by injecting reaction gas($N_2$) into a laser-generated melt pool and adjust the hardness to the specific requirements of the individual application by changing of laser processing parameters. This research has been investigated the effect of such parameters on TiN surface-alloying of Ti-6Al-4V alloy by $CO_2$ laser. The maximum hardness of TiN surface-alloyed zone waw obtained by injecting 100% $N_2$ gas and it was decreased as the amount of $N_2$ gas in Ar and $N_2$ gas mixture was decreased. As scanning speed was increased, the hardness and depth of TiN surface-alloyed zone was decreased at constant laser power. The surface hardness after double scanning laser treatment is higher than that of single scanning. At constant laser power, the surface roughness is increased after the surface alloying if laser scanning speed is decreased.

• 한국표면공학회지
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• 제52권2호
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• pp.53-57
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• 2019

Stability and activity of boron doped diamond (BDD) electrode are key factors for water treatment. In this study, BDD electrodes were prepared on various substrates such as Nb, Si, Ti, and $TiN_x/Ti$ by hot filament chemical vapor deposition (HFCVD) method. BDD/Ti film showed the delamination between BDD and Ti substrate due to the formation of TiC layer caused by diffusion of carbon. On the other hand, $BDD/TiN_x/Ti$ showed remarkably improved stability, compared to BDD/Ti. It was confirmed that $TiN_x$ intermediate layer act as barrier layer for diffusion of carbon. High potential window of 2.8 eV was maintained on the $BDD/TiN_x/Ti$ electrode and, better wastewater treatment capability and longer electrode working life than BDD/Nb, BDD/Si and BDD/Ti were obtained.

• 한국토양비료학회지
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• 제24권4호
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• pp.254-259
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• 1991

요소(尿素)가 사용된 초지의 토양단면(土壤斷面)에서 pH, 인산, 유기물 그리고 치환성(置換性) 양(陽)이온 함량의 계절적 변화를 조사하였다. 질소(窒素)비료 28kg N/10a을 시용하고 무질소구(無窒素區)와 목초(牧草)를 재배하면서 봄(5.26), 여름(7.27), 가을(10.18)철에 토양시료를 100cm까지 20cm 간격으로 채취하여, 토양(土壤) 화학성(化學性)을 비교(比較)한 결과는 다음과 같다. 1 봄, 여름철에 토양깊이 0~20cm에서 28kg N/10a 처리구의 pH는 질소 무처리구에 비하여 각각 0.7, 1.0 단위 낮았으며 토양깊이 20cm 이하에서도 28kg N/10a 처리구에서 pH가 낮아졌으며 계절별 pH감소 정도는 여름>봄>가을 순(順)이었다. 2. 토양 Bray No.1 인산 함량은 봄, 여름 철 질소무처리구와 28kg N/10a 처리간에 토양깊이별 차이가 없었으나, 여름철에 0~20cm 깊이에서의 인산함량은 봄철에 비하여 약 20ppm정도 낮았다. 가을철에는 28kg N/10a 처리의 토양깊이 20cm이하에서 인산함량이 봄, 여름철에 비하여 증가(增加)되는 경향을 보였다. 3. 유기물(有機物) 함량은 가을철에 질소 무처리구, 28kg N/10a 처리에서 공히 낮아지는 경향(傾向)이었으나, 대체적으로 질소시용량별, 토양깊이별 계절간 함량변화는 매우 적었다. 4. Ca 함량은 질소 무처리구, 28kg N/10a 처리 공히 토양깊이가 깊을수록 완만하게 감소(減少)되는 경향이었으나, 28kg N/10a 처리에서는 토양깊이 0~20cm에서의 함량이 봄철에 가장 높고 다음이 여름, 가을철 순(順)이었다. Mg과 K 함량은 질소 무처리구과 28kg N/10a 처리간에 계절별, 토양깊이별 차이가 거의 없었다. 5. 여름 철에 질소 무처리구에서는 $NH_4-N$ 함량과 pH, 유기물, Ca, Mg간에 정(正)의 유의상관(有意相關)이 있었고 28kg N/10a 처리에서는 $NO_3-N$함량과 토양 pH간에 부(負)의 유의상관(有意相關)(r=$-0.534^*$)이 있었다.

• 열처리공학회지
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• 제5권2호
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• pp.95-102
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• 1992

In this study, we tried to describe the quantitative model of TiN film structure which was deposited by PECVD process. The macro-grain growth behavior was studied at the various deposition pressures and times. As a result, It was confirmed that TiN films had the typical Zone 1 structure, and macro-columnar grains were, without reference to the deposition pressure, grown ballistic type by the growth-death competition following the equation, $Y=aX^2$, approximately obtained by regression analysis. Also, the thickness and the crystallization of TiN thin films were increased, the chlorine contents were decreased according to the decreasing of deposition pressure.

• 한국유기농업학회지
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• 제29권1호
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• pp.111-123
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• 2021

시설재배지에서 토양 양분으로 유기농업자재인 가축분 종류별 퇴비를 밑거름으로 처리한 후 발생하는 N₂O와 딸기의 생육 특성을 조사하기 위해 본 연구를 수행하였다. 가축분퇴비는 돈분과 우분, 계분을 원료로 하여 각각 만들어진 제품을 사용하였고, 딸기 표준시비량의 질소를 기준으로 단독 그리고 혼합 처리하였다. N₂O의 총배출량은 무기질비료 처리구와 비교하여 계분퇴비 처리구에서 10.7% 많았으나 다른 가축분퇴비 처리구에서는 16.5~41.9% 적게 배출되었다. N₂O가 주로 배출되는 기간은 비료살포 후 17일차까지로 전체 배출량의 70~87%를 차지하였고, 이후 158일간 13~30%가 발생하였다. N₂O 배출량은 토양의 NH₄⁺-N 함량과 부의 상관성을 나타내었다. 딸기의 생육 중 엽수, 엽폭, 관부직경은 처리구간 유의한 차이를 보이지 않았고, 엽장은 무기질비료 처리구보다 가축분퇴비 처리구에서 컸으며, SPAD 값은 우분퇴비와 계분퇴비를 혼합하여 시용한 처리구에서 가장 높았다. 딸기 과실의 무게와 당도는 처리구간 유의한 차이를 보이지 않았다.

• 청정기술
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• 제15권2호
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• pp.122-129
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• 2009

철이 이온교환된 상업용 베타제올라이트를 $450{\sim}900^{\circ}C$ 범위에서의 소성 및 수열처리 온도에 따른 아산화질소 직접분해 반응성을 관찰하였다. Fe-베타제올라이트의 특성분석을 위하여 XRD, $N_2$ 흡착 및 탈착, $^{27}Al-NMR$, XPS 분석을 수행하였다. $900^{\circ}C$에서의 소성처리 온도 및 $750^{\circ}C$에서의 수열처리 후의 Fe-베타제올라이트의 비표면적 및 기공 부피는 30% 정도 감소하였지만, 감소 정도는 수열처리 후에 더욱 심각하게 관찰되었다. 하지만 격자 안의 Al은 이온 교환된 Fe에 의하여 $900^{\circ}C$에서의 소성처리 후에도 낮은 탈알루미늄화에 의해 안정된 사면체 형태의 Al 상태를 유지하였다. 소성 및 수열처리 온도 증가에 따라 아산화질소의 분해반응 온도는 증가하였고 수열처리 후의 비활성화가 소성처리 후보다 심각하게 관찰되었다.