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>

Haplogroup Classification of Korean Cattle Breeds Based on Sequence Variations of mtDNA Control Region

Kim, Jae-Hwan,Lee, Seong-Su,Kim, Seung Chang,Choi, Seong-Bok,Kim, Su-Hyun,Lee, Chang Woo,Jung, Kyoung-Sub,Kim, Eun Sung,Choi, Young-Sun,Kim, Sung-Bok,Kim, Woo Hyun,Cho, Chang-Yeon Asian Australasian Association of Animal Productio 2016 Animal Bioscience Vol.29 No.5

Many studies have reported the frequency and distribution of haplogroups among various cattle breeds for verification of their origins and genetic diversity. In this study, 318 complete sequences of the mtDNA control region from four Korean cattle breeds were used for haplogroup classification. 71 polymorphic sites and 66 haplotypes were found in these sequences. Consistent with the genetic patterns in previous reports, four haplogroups (T1, T2, T3, and T4) were identified in Korean cattle breeds. In addition, T1a, T3a, and T3b sub-haplogroups were classified. In the phylogenetic tree, each haplogroup formed an independent cluster. The frequencies of T3, T4, T1 (containing T1a), and T2 were 66%, 16%, 10%, and 8%, respectively. Especially, the T1 haplogroup contained only one haplotype and a sample. All four haplogroups were found in Chikso, Jeju black and Hanwoo. However, only the T3 and T4 haplogroups appeared in Heugu, and most Chikso populations showed a partial of four haplogroups. These results will be useful for stable conservation and efficient management of Korean cattle breeds.

GPS/GPR을 이용한 저수지 준설능력 향상

이재원,이동락,엄장섭 東亞大學校 建設技術硏究所 2008 硏究論文集 Vol.31 No.2

일반적으로 퇴적물 준설에 대한 조사는 GPS/Echo Sounder 및 Total Station/Echo Sounder를 조합하여 대상지의 수평위치 및 수심에 대한 관측을 실시하고 있으며, 하상의 단면계산 저수량 및 준설계획량 등을 추정 이후 준설계획에 대한 계획고 및 준설토량에 대한 세부적인 계획을 수립하게 된다. 하지만 Echo Sounder를 사용하는 음파탐사 방법은 퇴적물에 대한 정확한 분포를 파악할 수 없는 단점이 있다. 본 연구는 저수지 하부의 퇴적물 및 이의 분포를 파악하여 저수지 준설계획을 수립하여 기존의 탐사방법에 대한 준설능력 향상에 중점을 두었으며, 기존의 음파탐사 방식과 다른 레이더탐사 장비를 이용한 GPS/GPR(Ground Penetration Radar)을 사용하여 저수지의 수평위치, 수심값을 결정하고 동시에 원 지반에 분포하고 있는 퇴적물의 분포를 추정, 준설에 적용하고자 하였다. 우선 현장의 시료채취를 통한 수조모형실험을 실시하여 장비에 대한 정확도 검증을 거친 후 현장적용에 적용하여 그 가능성을 평가하였다.

16주간 근력운동에 따른 국소부위 골밀도의 변화와 상관관계 특성

이재구,최무섭 한국유산소운동과학회 2002 대한스포츠융합학회지 (jcses) Vol.6 No.1

This study was performed to suggest the effects of mild strength exercise on local bone densities and the correlation characteristics among the various variables, body composition and local bone densities, in middle-aged women. The subjects were volunteered in 16 women being resident in the local community. Their ages were within 47.6±4.8 years. Body composition were analyzed by the Bioelectrical Impedence method(mode1; In Body.1999, Biospace Co. Korea), and local bone densities were measured by DEXA method(PIXI 5108 model, Lunar Co. USA). All subjects performed mild strength exercise, 3 timedweek during 16 weeks, Exercise session were constructured into warm up by walking and stretching 20min. and muscle training on the sites that measure the bone densities during 30 minutes. Results in this study were as following. Body compositions were significantly reduced in muscle volume 2.6% and body fat 3.63% after 16weeks . Local bone densities in the forearm were nonsignificantly 0.73% at 1/3 site and 1.24% at middle site, and ulna distal site was significantly decreased in 4.51% after 16wks. but total bone density in the forearm was reduced 1.4% nonsinificantly in the postexercise. Lumbar site was, also, increased 0.4% without significance at lumbar 2-4 level. All of three femoral sites, however, did increased nonsignificantly 1.58% at neck, 1.06% at greater trochanter, and 5.62% at ward's triangle in the postexercise. Serum calcium and osteocalcin values were significantly higher 13.7%(P=0.0000)and 54.1%(0.01) than before. Weight variable was significantly correlated with a bone density at a femoral neck site(r=0,34,P=0.05) and BMI had the significant correlation with neck(r=0.43,P=0.01) and greater trochanter(r=.44, P=0.01) in femur. Correlation characteristic among local bone densities appeared higher(r=0.41-0.71, P=0.01) between the lumbar and femur sites than those(r=0.38, P=0.02) between the lumbar and forearm sites. there was middle level(r=0.45-0.58, P=0.001.)between forearm and femur site. In conclusion, it was suggested that local bone density in middle-aged women can be increase through mild strength exercise over mechanical stress of ordinary lifestyle during 16 weeks.

A. 高校 科學 (生物·地球科學) 및 數學科 探究學習의 評價模型 定立과 評價紙 開發

李相協,權炳奎,林在圭,孫文求,吳岱燮,楊洪準,梁承榮,姜用熙,林成圭,金正遠,金吉民,兪正在 경북대학교 과학교육연구소 1982 科學敎育硏究誌 Vol.6 No.-

Currently the evaluation of high school science and mathematics learning has been too much knowledge-centered without concerning the inquiring ability or scientific attitude. This study, therefore, was made for the purpose of establishing of evaluation model for high school science (biology and earth science) and mathematics learning and its evaluation items. In this paper, the research was done about three fields, biology, earth science and mathematics. 1. For the biology, the evaluation methods of inquiry learning were studied with the foreign references, and proper evaluation items were suggested. 2. For the earth science, after analizing 5 kinds of earth science textbook of current using in high school, essential 19 items were selected. 5 of them were tested in test group and control group, then, the results were analized. 3. For the mathematice, the teaching elements of「Set」and「Flow chart」in mathematics (Ⅰ) were selected and structured. Detailed teaching objects were established and evaluation items were introduced.

중장년층에서의 외상성 견관절 탈구

이광원,류창수,김하용,안재훈,염진섭,김환정,최원식 대한견.주관절학회 2000 大韓肩.주關節學會誌 Vol.3 No.2

實驗大學 實施에 따른 師範大學 學生實態

李相魯,林在圭,吳岱燮,閔庚德 慶北大學校 師範大學 1977 敎育硏究誌 Vol.19 No.-

The purposes of this study were (1) to analyze students' reasons, for applying to the Teachers College, department and major; (2) to assess the degree of satisfaction on being assigned to their particular department; (3) to investigate their attitudes toward the new way of assigning students in terms of two broadly classified majors i.e., studies of humanistic and social sciences and studies of natural sciences; (4) to estimate the degree of fulfillment of student desire and degree of utility of physical facilities; and (5) to identify reasons of success or failure of the students in the respective departments they were assigned to. The subjects were 2 groups of Teachers College students, one group which entered the university in 1976 and the other in 1977. In order to collect data pertaining to students' opinions or attitudes, questioniares were used; the score on college entrance exam and grade point average were obtained from individual student reports. The data were statistically analyzed by means of either Z or chi-test. The major findings were as follows: 1. Approximately 41 percent of the freshmen of the Teachers College reported that they decided to enter the Teachers College in order to be teachers. 2. Approximately 70 percent of the Teachers College students decided their particular major by themselves rather than by suggestions or advices. 3. The degree of satisfaction on having entered the Teachers College was relatively high, since the average scale point was .472. 4. The fresh students showed a significant decrease in their positive attitude toward the new way of assigning the students to the department or majors. The average scale point of the students in 1975 was .276; that of in 1976 was .489; that of the students in 1977 was .077. When the changes in attitude toward the new way of assigning students to departments or majors were estimated, it was observed that the degree of those in favor was .489 at the beginning of the first semester, and-.677 at the end of the second semester. However, the degree of satisfaction reported by students after they were assigned to a specific department or major was .732. Therefore, the negative attitude toward the new way of assigning could be interpreted as a reflection of students' anxiety status of rather than an attitude against the new way of assigning the students.

敎育實習을 通한 授業體制改善의 實踐的 硏究 : 指導案樣式의 開發 Centered on Lesson Plan Format

李慶燮,林在圭,琴種友,鄭浩杓 慶北大學校 師範大學 1979 敎育硏究誌 Vol.21 No.-

This study was undertaken to construct a lesson plan format appropriate for our educational status. To achieve this aim, the following two processes were pursued: first, to investigate the relation between curriculum and lesson plan format; second, to analyze and discuss the lesson plan model used practically in American Schools. Instructional objectives, Structure of contents, instructional processes, and width of instruction are regarded as the fundamental elements of proper lesson plans by this investigation. In terms of theoretical ground about each of the above-mentioned elements, the following lesson plan format, which can be put to a practical use in our educational status, was constructed.

12주간 복합운동이 여성 중, 고령자의 신체조성, 혈중변인, 생리적인 변인 및 근력에 미친 효과

이재구,최무섭 한국유산소운동과학회 2003 대한스포츠융합학회지 (jcses) Vol.7 No.1

The purpose of this study was to investigate the comprehensive alterations on body composition, blood profile, physiological variables, and muscle strength, that result from combination of aerobic exercise and muscular endurance training during 12 weeks. Methods in this study; 37 healthy women were involved in subjects. All of them were screened by questionnaire, direct interview, blood profile test, and graded exercise test. They did exercise 3 times sessions per week, programmed with walking and jogging on treadmill and 8 muscular exercises to the local sites of body by free weight instruments. All exercise session have been performed by supervised exercise. Results; Body weight reduced significantly about 1.8kg(p<.05 after 12 weeks. Middle-aged group was higher reduction of body weight than the other groups. However, there were no significant changes on body fat and lean body mass after exercise. blood glucose in fasting reduced significantly after 12 wks(8㎎/dl, p<.01). Significant reductions in total cholesterol(18㎎/dl, p<.01)and triglyceride(39㎎/dl, p<.01)were observed post exercise. In case of muscular strength, eccentric contraction increased sigmficantly 8-9 peak force(p<.05) after 12 wks. but concentric contraction was not after exercise. Physiologic variables such as HR, systolic and diastolic BP, and RPP decreased significantly after exercise, 8 beats/min, 16 ㎜Hg, 9 ㎜Hg, and 4,477 beats/min-㎜Hg, respectively. and exercise duration time on treadmill was longer 15%(p<.05) than that of pe-exercise. In conclusion, combine exercise program in this study is effective exercise modality to improve blood profile, physiologic variable, and muscle strength among middle-aged and elder women.

생쥐 대장 평활근 세포에서 내향 정류성 칼륨 전류의 특성 연구

이은주,김명,정명섭,조향훈,김기훈,하현철,김준수,최석,전제열 朝鮮大學校 附設 醫學硏究所 2006 The Medical Journal of Chosun University Vol.31 No.2

Objectives: K^(+) channels play an important role in regulating cellular excitability. The aim of this study was to know whether or not inward rectifier K^(+) channel exists in colonic smooth muscle cells. Methods: Mouse colonic smooth muscle cells were isolated using collagenase, and then we recorded their membrane currents using a whole-cell patch clamp technique. Results: With 90 mM K^(+) in bath, hyperpolarization-induced inward currents from -120 mV to 20 mV with 400 ms duration at a holding potential of -10 mV showed rapid activation, inactivation and inward rectification. The inactivation showed single exponential time course. Reduction of external K^(+) to 60 mM decreased the amplitudes of the currents in whole test voltage range and shifted the reversal potential to more negative potential. The inactivation process and peak currents of hyperpolarization-induced inward currents were not affected by removing external Na^(+). External Ba^(+) blocked hyperpolarization-induced inward currents by dose-dependent manner and pure Ba^(+)-sensitive currents showed strong inward rectification. Cs^(+) also suppressed hyper- polarization-induced inward currents. Ba^(+) and Cs^(+)-induced inhibitiOn of hyperpolarization-induced inward currents was voltage-dependent, and the extent of inhibition increasing with membrane hyperpolarization. Conclusions: These results suggest that inward rectifier KU channels may exist in proximal colonic smooth muscle and may play an important role in regulating membrane potential.