A sub-1-volt nanoelectromechanical switching device.

Lee, Jeong Oen,Song, Yong-Ha,Kim, Min-Wu,Kang, Min-Ho,Oh, Jae-Sub,Yang, Hyun-Ho,Yoon, Jun-Bo Nature Pub. Group 2013 Nature nanotechnology Vol.8 No.1

<P>Nanoelectromechanical (NEM) switches have received widespread attention as promising candidates in the drive to surmount the physical limitations currently faced by complementary metal oxide semiconductor technology. The NEM switch has demonstrated superior characteristics including quasi-zero leakage behaviour, excellent density capability and operation in harsh environments. However, an unacceptably high operating voltage (4-20 V) has posed a major obstacle in the practical use of the NEM switch in low-power integrated circuits. To utilize the NEM switch widely as a core device component in ultralow power applications, the operation voltage needs to be reduced to 1 V or below. However, sub-1 V actuation has not yet been demonstrated because of fabrication difficulties and irreversible switching failure caused by surface adhesion. Here, we report the sub-1 V operation of a NEM switch through the introduction of a novel pipe clip device structure and an effective air gap fabrication technique. This achievement is primarily attributed to the incorporation of a 4-nm-thick air gap, which is the smallest reported so far for a NEM switch generated using a 'top-down' approach. Our structure and process can potentially be utilized in various nanogap-related applications, including NEM switch-based ultralow-power integrated circuits, NEM resonators, nanogap electrodes for scientific research and sensors.</P>

두경부자세 및 혀, 설골의 위치가 두개안면형태에 미치는 영향에 관한 연구

오진섭,태기출,국윤아,김상철 대한치과교정학회 1998 대한치과교정학회지 Vol.28 No.4

두경부 자세 및 혀, 설골의 위치와 두개안면골격간의 연관성을 알아보기 위해, 원광대학교 치과대학 재학생 중 선천적 두경부 이상이나 결손치가 없고 과거 교정 치료나 보철치료의 경험이 없는 남자 50명과 여자 40명을 대상으로 natural head position(NHP)상태에서 두부방사선 사진을 채득하여 전통적인 두개내 참고선과 두개의 진성 참고선을 이용하여 계속한 결과 다음과 같은 결론을 얻었다. 1. 두경부 자세변수들에서는 남녀간 차이가 없었으나, 설골의 위치는 남자가 여자에 비해 더 전하방에 위치하였으며, 더 큰 전하방 경사도를 보였다. 2. 경추의 경사도가 클수록 NHP에서 안면돌출도는 작게 나타났으며, 경추의 전방만곡이 증가할수록 수직적인 안모형태를 보였다. 3. 두경부각이 작을수록 두개저에 대하여 설골이 전방에 위치하였으며, 두경부각과 설골의 수직적인 위치는 연관성을 보이지 않았다. 4. 하악골이 전돌될수록 설골은 전방에 위치하였으며, 두개안면형태와 설골의 수직적인 위치는 미약한 연관성을 나타냈다. The purpose of this study was to examine the associations of head posture, the position of the tongue or the hyoid bone to craniofacial structure. Cephalograms taken in Natural head position(NHP) of 90 dental students (50 in male, 40 in female, 20 to 30 years in age) were traced and measured using the extracranial true horizontal and vertical lines. The obtained results were as follows; 1. There was no sex difference in head posture, but the hyoid bone was placed anteroinferiorly in male more than in female and anteroinferior inclination of the hyoid bone showed greatly in male. 2. The more inclined was the cervical column, the less prognathic was the face in natural head posture, and the larger cervical curvature, the more vertical pattern of the face. 3. The less small showed craniocervical angulation, the more anteriorly placed was the hyoid bone to the cranial base, and there was no significantly association between craniocervical angulation and the vertical position of the hyoid bone. 4. The more prognathic was the mandible, the more anteriorly placed was the hyoid bone, and there was slightly association between the craniofacial morphology and the vertical position of the hyoid bone.

주거형태에 따른 일반인의 환경의식 행태에 관한 연구

윤오섭,김광환 大田産業大學校 2000 한밭대학교 논문집 Vol.17 No.1

The result of the study and analysis on the formation and the mutual relation of environmental consciousness followed by residential forms are as bellows; The ratios of the subjects of this study for each gender are ; 68.1% of male and 31.9% of female. And the group of aged thirty to thirty-nine occupied 33.2% as the majority. Each residential group comes up to 65.0% of using washstand when they wash their faces and hands. While being in the kitchen, 55% of individual housing residents and 61.8% of tenement housing residents are using basins, and the ratios are occupied very highly. 52.5% of discharged water which is accrued from the rice-wash is used for flower gardens and dish washing, and the ratio of direct discharging the water comes up to a very high ratio regardless the residential forms. 33.2% of the subjects of this study do car washes, and the residents living in the tenement housings and apartments do more car washes than the residents living in the individual housings do. 51% of the subjects or this study do warm-ups of the automobiles and apartment residents highly grasp the warm-up ratio while individual housing residents showed lesser warm-ups. 57.2% of the subjects of this say, they do not know well about the greenhouse gas and the tenement residents occupied high ratio. 10% of individual housing residents do not recycle garbage and this group grasps the highest rate. 57.6% of the entire subjects of this study do separate discharge of the rubbish but 61.8% of the individual residents do not separate discharge.

SF-36을 이용한 농촌 노인들의 건강상태 평가

전진용,김상아,박웅섭,오미경,홍윤미 관동대학교 의과학연구소 2001 關東醫大學術誌 Vol.5 No.1

This study was conducted to understand health status by general characteristic, and to find out relationship between the general characteristics and rural elderly's health status. Health status was measured using SF-36(Medical Outcome Study Short From 36). The finding of this study were as follow; Mean scores of health status by sex were higher in male on physical function, social function and role limitation-emotion. The elderly educated more reported good health on physical function, role limitation-physical, vitality, bodily pain and general health than did the elderly educated less. The elderly who have disease reported bad health on social function, mental health and general health. Therefore we reviewed the evidence that sex, education and illness are associated with health status in the elderly, and that specific public health service that related such condition should be considered for the rural elderly.

선택적 환원 촉매(SCR)에서 배출가스 특성에 따른 NO<SUB>x</SUB> 변환효율 및 환원제(NH₃) 분사량 최적화에 관한 실험적 연구

오준석(June-Seok Oh),윤여빈(Yu-Bin Yoon),송춘섭(Chun-Sub Song),박영준(Young-Joon Park),이성욱(Seang-Wock Lee),조용석(Yong-Seok Cho) 한국자동차공학회 2009 한국자동차공학회 부문종합 학술대회 Vol.2009 No.4

The selective catalytic reduction(SCR) system is potentially a highly-effective means of NO<SUB>x</SUB> reduction for diesel engine. Generally, SCR makes use of a reductant added to the exhaust gas that can be used for reacting NO and NO₂ to N₂. The reductant, ammonia(NH₃) generated from a liquid urea-water solution. De-NO<SUB>x</SUB> process in the SCR, the ideal ratio of NH₃ molecules to NO<SUB>x</SUB> molecules is 1:1 for high efficiency of NO<SUB>x</SUB> reduction. The SCR system has good NO<SUB>x</SUB> reduction performance in the temperature window of about 250 to 400℃, low space velocity also leads an increase of NO<SUB>x</SUB> reduction efficiency, due to long residence time in the catalyst. This paper reviews a laboratory study to evaluate the effects of NO<SUB>x</SUB>-NH₃ concentrations, gas temperature and space velocity on the NO<SUB>x</SUB> reduction efficiency of the SCR. The maximum reduction efficiency is indicated when the NH₃ to NO<SUB>x</SUB> ratio is 1.2 and the space velocity is 30,000 h?¹ in 300℃. However, under various exhaust conditions, NH₃ injection amount need to be controlled for a high NO<SUB>x</SUB> conversion efficiency because of reducing unnecessary NH₃ consumption. Based on results of the rig-test, this study suggests the control strategy of NH₃ injection for optimizing NO<SUB>x</SUB> reduction efficiency.

Structure-tunable synthesis of titanate nanotube thin films via a simple hydrothermal process

Guo, Yupeng,Lee, Nam-Hee,Oh, Hyo-Jin,Yoon, Cho-Rong,Park, Kyeong-Soon,Lee, Hee-Gyoun,Lee, Kyung-Sub,Kim, Sun-Jae IOP Pub 2007 Nanotechnology Vol.18 No.29

<P>In this study, titanium metal acts as the titanium source to prepare oriented titanate nanotube thin film. The effects of preparation parameters, such as reaction temperature, duration and post-treatment conditions, on the film morphology and stability have been examined. A general formation mechanism for oriented titanate nanotube thin film is proposed on the basis of detailed observations of the products using two-dimensional surface SEM studies and TEM images. The overall formation of titanate nanotubes can be summarized as a sequence of four steps: (a)?titanium dissolution and alkali titanate hydrogel formation; (b)?alkali titanate hydrogel dissolution, increased TiO<SUB>3</SUB><SUP>2−</SUP>, TiO<SUB>2</SUB>(OH)<SUB>2</SUB><SUP>2−</SUP> or Ti<SUB><I>n</I></SUB>O<SUB>2<I>n</I>+<I>m</I></SUB><SUP>2<I>m</I>−</SUP> concentration and layered Na<SUB>2</SUB>Ti<SUB>3</SUB>O<SUB>7</SUB> formation; (c)?layered Na<SUB>2</SUB>Ti<SUB>3</SUB>O<SUB>7</SUB> growth; (d)?nanotube formation via Na<SUB>2</SUB>Ti<SUB>3</SUB>O<SUB>7</SUB> splitting and the multilayer scrolling process. The Na<SUB>2</SUB>Ti<SUB>3</SUB>O<SUB>7</SUB> lamellar structures split between the (010) planes into nanosheets. </P>

Prediction of distant metastasis and survival in adenoid cystic carcinoma using quantitative ¹⁸F-FDG PET/CT measurements

Lim, Won Sub,Oh, Jungsu S.,Roh, Jong-Lyel,Kim, Jae Seung,Kim, Soo-Jong,Choi, Seung-Ho,Nam, Soon Yuhl,Kim, Sang Yoon Elsevier 2018 Oral oncology Vol.77 No.-

<P><B>Abstract</B></P> <P><B>Objectives</B></P> <P>Adenoid cystic carcinoma (AdCC) in the salivary gland shows a high rate of distant metastasis, which is related to the resulting poor prognosis. We therefore examined the role of pretreatment <SUP>18</SUP>F-FDG PET/CT for prediction of distant metastasis, recurrence/progression, and survival in AdCC.</P> <P><B>Methods</B></P> <P>This study included 52 patients who underwent pretreatment <SUP>18</SUP>F-FDG PET/CT scanning and subsequent treatments for AdCC. Maximum, mean, and peak standardized uptake value (SUV<SUB>max</SUB>, SUV<SUB>mean</SUB>, and SUV<SUB>peak</SUB>), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were measured on <SUP>18</SUP>F-FDG PET/CT. Univariate and multivariate Cox proportional hazards regression analyses were used to identify associations between the quantitative measurements of <SUP>18</SUP>F-FDG PET, and progression-free survival (PFS), distant metastasis-free survival (DMFS), and disease-specific survival (DSS).</P> <P><B>Results</B></P> <P>Distant metastases were found in 20 (39%) patients: 6 (12%) at initial diagnosis and 14 (27%) during the median follow-up of 72 months after treatment. Univariate analyses showed that all the <SUP>18</SUP>F-FDG PET parameters of SUV<SUB>max</SUB>, SUV<SUB>mean</SUB>, SUV<SUB>peak</SUB>, MTV, and TLG were significantly associated with overall PFS, DMFS, and OS (all <I>P</I> < .05). After controlling for clinicopathological variables, SUV<SUB>max</SUB> remained an independent factor predictive of PFS (<I>P</I> = .001), while MTV and TLG were independent predictors of DMFS (<I>P</I> = .009) and DSS (<I>P</I> = .017). Patients with MTV > 14.8 mL showed a 5.9-fold higher risk of distant metastasis and a 4.2-fold higher risk of disease-specific death than those with a lower MTV.</P> <P><B>Conclusions</B></P> <P>Quantitative measurements using <SUP>18</SUP>F-FDG PET/CT are useful for predicting tumor progression, distant metastasis, and survival in patients with AdCC.</P> <P><B>Highlights</B></P> <P> <UL> <LI> SUV<SUB>max</SUB>, SUV<SUB>mean</SUB>, SUV<SUB>peak</SUB>, MTV, and TLG were measured on pretreatment <SUP>18</SUP>F-FDG PET/CT of 52 adenoid cystic carcinoma patients. </LI> <LI> SUV<SUB>max</SUB> (>3.2) was an independent factor predictive of progression-free survival (<I>P</I> = .001). </LI> <LI> MTV and TLG were independent predictors of distant metastasis-free and disease-specific survival (<I>P</I> < .05) </LI> <LI> MTV > 14.8 mL or TLG > 45.5 g was associated with a >4-fold increased risk of distant metastasis and mortality. </LI> </UL> </P>

Hypothermia Inhibits Endothelium-Independent Vascular Contractility via Rho-kinase Inhibition

( Yoon Hee Chung ),( Keon Woong Oh ),( Sung Tae Kim ),( Eon Sub Park ),( Hyun Dong Je ),( Hyuk-jun Yoon ),( Uy Dong Sohn ),( Ji Hoon Jeong ),( Hyen-oh La ) 한국응용약물학회 2018 Biomolecules & Therapeutics(구 응용약물학회지) Vol.26 No.2

The present study was undertaken to investigate the influence of hypothermia on endothelium-independent vascular smooth muscle contractility and to determine the mechanism underlying the relaxation. Denuded aortic rings from male rats were used and isometric contractions were recorded and combined with molecular experiments. Hypothermia significantly inhibited fluoride-, thromboxane A_2-, phenylephrine-, and phorbol ester-induced vascular contractions regardless of endothelial nitric oxide synthesis, suggesting that another pathway had a direct effect on vascular smooth muscle. Hypothermia significantly inhibited the fluorideinduced increase in pMYPT1 level and phorbol ester-induced increase in pERK1/2 level, suggesting inhibition of Rho-kinase and MEK activity and subsequent phosphorylation of MYPT1 and ERK1/2. These results suggest that the relaxing effect of moderate hypothermia on agonist-induced vascular contraction regardless of endothelial function involves inhibition of Rho-kinase and MEK activities.

Lipid production in <i>Porphyridium cruentum</i> grown under different culture conditions

Oh, Sung Ho,Han, Jae Gun,Kim, Young,Ha, Ji Hye,Kim, Seung Seop,Jeong, Myoung Hoon,Jeong, Hyang Suk,Kim, Na Young,Cho, Jeong Sub,Yoon, Won Byong,Lee, Shin Young,Kang, Do Hyung,Lee, Hyeon Yong Elsevier 2009 Journal of bioscience and bioengineering Vol.108 No.5

<P><B>Abstract</B></P><P>Autotrophic growth of <I>Porphyridium cruentum</I> under 18:12?h and 12:12?h light:dark cycles showed the maximum cell concentration of 2.1?g-dry wt./L, whereas the specific growth rate, 0.042 (1/h), at 18:6?h is faster than that of 12:12?h, 0.031 (1/h), respectively. The highest lipid accumulation level, 19.3 (%, w/w), was achieved at 12:12?h cycle. Under dark cultivation condition with 10?g/L of glucose, the lipid accumulation in the cell was 10.9 (%, w/w), whereas the heterotrophic growth with glycerol as the carbon resource showed low level of cell concentration and lipid production, compared to that of glucose. The glucose was decided to be a suitable carbon resource for the heterotrophic growth of <I>P. cruentum</I>. The lipids from <I>P. cruentum</I> seemed be feasible for biodiesel production, because over 30% of the lipid was C<SUB>16</SUB>–C<SUB>18:1</SUB>. The cultivation time and temperature were important factors to increase the maximum cell concentration. Extending the cultivation time helps maintain the maximum cell concentration, and higher lipid accumulation was achieved at 25?°C, compared to 35?°C. The fed-batch cultures showed that, under the light condition, the specific production rate was slightly decreased to 0.4% lipid/g-dry wt./day at the later stage, whereas, under the dark condition, the specific production rate was maintained to be a maximum value of 1.1% lipid/g-dry wt./day, even in the later stage of cultivation. The results indicate that the heterotrophic or 12:12?h cyclic mixotrophic growth of <I>P. cruentum</I> could be used for the production of biodiesel in long-term fed-batch cultivation of <I>P. cruentum</I>.</P>

A Study on the Environmental Pollution in Solid Waste Landfill

( Oh Sub Yoon ) 대한보건협회 1989 대한보건협회 보건종합학술대회 Vol.- No.-