세관 양광주 방전에서 플라즈마 확산의 완전 해

김동준,정종문,김정현,황하청,정재윤,조윤희,임현교,구제환,최은하,조광섭,Jin, D.J.,Jeong, J.M.,Kim, J.H.,Hwang, H.C.,Chung, J.Y.,Cho, Y.H.,Lim, H.K.,Koo, J.H.,Choi, E.H.,Cho, G.S. 한국진공학회 2010 Applied Science and Convergence Technology Vol.19 No.1

관경이 수 mm인 세관 램프 내부에서 플라즈마의 확산을 조사하기 위하여 이극성(ambipolar) 확산방정식을 해하였다. 반경 방향의 확산에 의한 유리관 벽에서의 플라즈마 소멸 특성시간은 $\tau_r\;=\;(r_0/2.4)^2/D_a$로 주어진다. 반경 $r_0{\sim}1\;mm$이고 이극성 확산계수 $D_a{\sim}0.01\;m^2/s$ 이면, $\tau_r{\sim}17\;{\mu}s$이다. 이는 램프의 교류전원 구동에서 플라즈마를 유지하기 위한 구동 최소 주파수 ~30 kHz에 해당한다. 고전압이 인가되는 전극부에 발생한 고밀도의 플라즈마가 양광주로 확산되는 특성시간은 $\tau_z{\sim}0.1\;s$이다. 고밀도 플라즈마 경계에서의 시간에 대한 확산속도는 $t{\sim}10^{-6}\;s$일 때 $u_D{\sim}10^2\;m/s$이고, $t{\sim}10^{-3}\;s$이면 그 속도는 $u_D{\sim}1\;m/s$로 느려진다. 따라서 램프 길이 ~1 m에 대하여 전극부에서 생성된 고밀도 플라즈마가 양광주 전체로 확산되는 시간은 수 초가 걸린다. The ambipolar diffusion equation has been solved in a fine-tube lamp of a few mm in diameter. In the diffusion of radial direction, the plasma diffuses and vanishes away at the glass wall by recombination with the characteristic time of plasma loss is given by $\tau_r\;=\;(r_0/2.4)^2/D_a$. With the radius $r_0{\sim}1\;mm$ and the ambipolar diffusion coefficient $D_a{\sim}0.01\;m^2/s$, the vanishing time is calculated $\tau_r{\sim}10\;{\mu}s$ which corresponds to the least value of frequency 30 kHz for the sustaining the plasma in the operation of high voltage AC-power. In the diffusion of longitudinal z-direction, a high density plasma generated at the area of a high voltage electrode, diffuses into the positive column with the characteristic time $\tau_z{\sim}0.1\;s$. The plasma diffusion velocity at the boundary of high density plasma is $u_D{\sim}10^2\;m/s$ at the time $t{\sim}10^{-6}$ s and the diffusion velocity becomes slow as $u_D{\sim}1\;m/s$ at $t{\sim}10^{-3}\;s$. Therefore, for the long lamp of 1 m, it takes about several seconds for the high density plasma at the area of electrode to diffuse through the whole positive column space.

2단계 급속동결 및 초자화 동결한 토끼상실배의 체외생존성에 관한 연구

정구민,이창규,임경순,김수헌 서울대학교농과대학농업개발연구소 1990 서울대농학연구지 Vol.15 No.1

본 시험은 수정란 급속동결보존기술의 개발을 위한 기초자료를 얻기 위하여 2단계 급속동결 및 초자화동결이 토끼 상실배의 체외발생등에 미치는 영향을 검토하고자 실시하였으며, 얻어진 결과는 다음과 같다. 1. 토끼 상실배를 1.5, 2.0, 2.5 및 3.0 M glycerol과 0.5 M sucrose가 포함된 동결액에 실온에서 10분간 노출후 -30℃에서 30∼40분간 정치하여 급속동결하였을 때 발생율은 각각 36.4, 83.3, 92.3 및 84.2%로 2.5 M glycerol에서 가장 높았다. 2. 토끼 상실배를 1.5, 2.0, 2.5 및 3.0 M 1,2-propanediol과 0.5 M sucrose가 포함된 동결액에 실온에서 10분간 노출 후 -30℃에서 30∼40분간 정치하여 급속동결하였을 때 발생율은 각각 26.6, 55.6, 65.0 및 52.9%로 2.5 M 1,2-propanediol에서 가장 높았으나, glycerol을 사용했을 때 보다 낮았다. 3. 토끼 상실배를 2.5, 3.0 및 3.5 M glycerol과 0.5 M trehalose가 포함된 동결액에 실온에서 10분간 노출후 액체질소에 침지하여 초급속동결한 결과 회수율은 각각 87.5, 92.5 및 92.5%, 형태적으로 정상인 수정란의 비율은 각각 37.5, 55.5 및 60.0%, 그리고 발생율은 각각 13.3, 36.4 및 37.5%로 3.5 M glycerol에서 가장 높았으나 초자화동결법보다 현저하게 낮았다. 4. 토끼 상실배를 25% glycerol과 25% 1,2-propanediol을 함유한 동결액에 실온에서 10분간 노출후 초자화동결했을 때 발생율은 75.0%로 실온에서 형평한 후 초자화동결이 가능하였다. This experiment was carried out to investigate on in vitro development of rabbit monla frozen by 2-step feezing and vitrification. The results obtained from this experiment are as follows; 1. When rabbit morula in m-PBS containing 1.5, 2.0, 2.5 or 3.0 M glyceral and 0.5 M sucrose for 10 min at room temperature were cooled at -30℃ for 30 to 40 min and plunged into liquid nitrogen, the proportion of embryo developed to expanded blastoyst was 36.4, 83.3, 92.3 and 84.2%, respectively. Glycerol 2.5 M showed higher survival than others. 2. When rabbit morula in m-PBS containing 1.5, 2.0, 2.5 or 3.0 M 1, 2-propanediol and 0.5 M sucrose for 10 min at room temperature were cooled at -30℃ for 30 to 40 min and plunged into liquid nitrogen, the proportion of embrye developed to expanded blastocyst was 26.6, 55.6, 65.0 and 52.9%, respectively. 1, 2-propanediol was less effective than glycerol. 3. When rabbit morula in m-PBS containing 2.5, 3.0 or 3.5 M glycerol and 0.5 M trehalose for 10 min at room temperature were plunged into liquid nitrogen and thawed rapidly, the recovery rate of embryo was 87.5, 92.5 and 92.5%, the proportion of morphologically normal embryo was 37.5, 55.5 and 60.0%, and the proportion of embryo developed to expanded blastocyst was 13.3. 36.4 and 37.5%, respectively. The proportion of embryo developed to expanded blastocyst was higher in vitrification than in plunging into liquid nitrogen. 4. When rabbit morula were frozen by vitrification in m-PBS containing 25% glycerol. 25% 1, 2-propanediol, the proportion of embryo developed to expanded blastocyst was 75.0%, the result suggested that rabbit embryos could be frozen by vitrification after equilibration at room temperature.

Geological and Geotechnical Characteristics of Marine Clay in Busan New Port

Chung, S.G,E. Ninjgarav,M. Suneel,K.Ganapathi Rao,Kim, G.J. 東亞大學校 建設技術硏究所 2005 硏究論文集 Vol.28 No.2

Since early 1990s reclamation projects for Busan and its vicinity in Nakdong River plain have been performed for industrial and residential complexes. As well it has started to build a new port (Busan Newport) with increase in overloads of Busan port since late 1990s. In the area the sedimentary deposit is composed of soft clay of about 30m thick, thin sand layer of 3-4m thick, hard clayey soil, and then basal conglomerates and sandy sediments, total thickness of which is about 70m at maximum under seawater. For the huge project many contract companies have simultaneously performed geotechnical investigations to get design parameters. Based on the harmful experiences gained by the previous projects, it was also required to pay careful attention to sampling and laboratory and field tests for theproject. Nevertheless the results of laboratory tests were so scattered and then resulted in difficulty to evaluate the design parameters. Existing data has been reviewed to evaluate the validity or cause of their variation. In addition geological study, sampling and soil tests have been carefully carried out at a few locations. Using the results the clay would be effectively characterized for depositional environment and its relation to soil properties.

體力章制度의 關心度比較에 關한 調査硏究 : 馬山市 男子高等學校 進學, 比進學者를 中心으로 Comparison of advancing to higher education and onadvancing highe education for the boy high school, Masan-si

鄭民煥,李錫南,朴昌植,丁小鳳,金成根 경희대학교 체육과학연구소 1978 體育學論文集 Vol.6 No.-

In the result of the research on the interests to the physical strength code system of boy high school (Comparison) of advancing to higher education and nonadvancing to higher education), it was possible to deduce the following conclusion and the suggestions from the theoretical background and the assumptions mentioned above forwarded by this research. 1. The understanding in the system of P.S.C. in inefficient. 2. The system failed to provide to one's strengh buiding 3. The training for P.S.C. is always not practiced consistently but being exercised on the immediate of inspection. 4. The understanding on the itemized purpose of its inspection is relatively low. 5. The inspection has something to do with the entrance examination and conderned because of the directive score points. 6. The inspection system failed to show a fairness and a lot of contradictions have been pointed out in the course of its execution. 7. In a comparison of advancing to higher education and nonadvanoing to higher education, the latter has not considered a special necessity. 8. The relative importance for the entrance examination by current inspection of P.S. has shown as fitted one. 9. It is not well comed to practice only in the training of P.S.C. at the assigned time to P.S. From the above conclusion, the following suggestions are required. 1. It is required that the system of P.S.C. is to be equally alotted to the all physical curriculum so that the guidance with the possitive plans be undertaken in the ordinal time. 2. It should not be limited of the system of P.S.C. in reflecting to the result of entrance examination for the boys of advancing to higher educations, and but considered in the dimension of national aspects, and the systematic backing policy enabling to exercise with a interest to the system of P.S.C even for the group of non-advancing for higher education be necessary. 3. A objectivity making the inspection thorough and correct in the course of execution, of the system of P.S.C. is required. 4. The fairness of inspection should be maintained by a sufficient training in advance for the staffs of the physical strength inspection and the inconsistencies should be developed. 5. The items of sport(Swiming, physical exercise, shooting etc.) beside the items of current P.S. inspection is recommended to be added. In the end, by strengthening the grade of current P.S. inspection, it is necessary to let people know that it Is very hard to get a special grade without a consistent effort in ordinary day.

Salmonella Typhi, Salmonella Typhimurium 및 Salmonella Enteritidis의 항균제 감수성 (1997)

신영학,유정식,김기상,정동준,오경수,이점규,이상원,이근영,박미선,이복권,김호훈 국립보건연구원 1998 국립보건원보 Vol.35 No.-

Rhizome Germination Rate of Miscanthus x giganteus at Different Rhizome Sizes

( Chung Y. S. ),( M. Park ),( S. Lee ) 강원대학교 농업생명과학연구원(구 농업과학연구소) 2018 강원 농업생명환경연구 Vol.30 No.2

Miscanthus is a perennial rhizomatous grass that originated in the tropics and subtropics, although different species are found throughout a wide climatic range. In general, Miscanthus are grown from rhizomes under greenhouse conditions and subsequently transplanted into the field. To manage plants well, it is important to have uniform germination. However, the impact of rhizome size on the germination rate of Miscanthus species has not been thoroughly studied. The impact of rhizome size on germination rate and germination days was therefore investigated in three Miscanthus species (M. sinensis, M. sacchariflorus, and M. x giganteus). There was no considerable variation in germination days between the three Miscanthus species studied. However, the germination rate varied depending on rhizome size. Rhizome size does not affect the germination rate of M. sacchariflorus; thus, small rhizomes can be used for planting. The results of this study suggest the use of 15-20 g of rhizomes for M. giganteus and M. sinensis to ensure a 100% rate of germination.

M-13 bacteriophage based structural color sensor for detecting antibiotics

Moon, J.S.,Park, M.,Kim, W.G.,Kim, C.,Hwang, J.,Seol, D.,Kim, C.S.,Sohn, J.R.,Chung, H.,Oh, J.W. Elsevier Sequoia 2017 Sensors and actuators. B Chemical Vol.240 No.-

Color sensor systems that exploit the advantages of M-13 bacteriophage have been shown to be potentially useful for detection of hazardous materials. The properties of M-13 bacteriophage can be systemically modified to impart target-specific selectivity and sensitivity using the phage display technique. Here, we describe a structural color-based sensor that utilizes genetically engineered M-13 bacteriophage to discriminate different types of antibiotics. An M-13 bacteriophage based structural color matrix was fabricated using a simple pulling technique by self-assembly of M-13 bacteriophage. When exposed to organic solvent, M-13 bacteriophage bundles promptly swell and promote distinct structural color change. Color sensors composed of M-13 bacteriophage genetically engineered to possess WHW peptide motifs clearly discriminated three different types of antibiotics, which was based on the color analysis of sensor using principal component analysis. Our sensing approach based on M-13 bacteriophage could be a promising sensor technique such as an environmental monitoring system.

Investigations in to the Capacity and Strength of Rhizome Germination in Three Different Miscanthus Species

( Chung Y. S. ),( M. Park ),( S. Lee ) 강원대학교 농업생명과학연구원(구 농업과학연구소) 2018 강원 농업생명환경연구 Vol.30 No.2

Miscanthus is a perennial rhizomatous grass. Among Miscanthus species, M. sinensis, M. sacchariflorus, and M. x giganteus and their varieties are widely planted worldwide. However, M. x giganteus must be propagated vegetatively owing to its sterility. Therefore, its propagation poses significant challenges both economically and to production efficiency. Most M. x giganteus is propagated by rhizomes that form nodes, internodes, and buds in a similar manner to above-ground stems. Therefore, we investigated the germination rate and strength of three different Miscanthus species, M. sinensis, M. sacchariflorus, and M. x giganteus. We found that, of these species, M. sacchariflorus performed best in terms of both germination rate and strength. The results of the current study could provide the starting point for further and extensive study of rhizome germination in Miscanthus species.

Raised Source-Drain Transistors in a Cell and Support Area with Co-Silicide for 88-nm DRAM Technology and Beyond

Y.M. Choi,B.J. Park,D.H. Kim,D.I. Kim,D.S. Hwang,H. K. Hwang,H.J. Kim,H.S. Kim,I.B. Chung,J.M. Park,J.W. Lee,J.Y. Kim,Kinam Kim,M.H. Jo,정문영,N.J. Kang,S.E. Kim,Y.J. Park,Y.S. Hwang 한국물리학회 2004 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.44 No.1

Full integration of a 512-Mb dynamic random access memory (DRAM) using both a raised sourcedrain (S/D) in a cell and a support area with additional Co silicidation in the support area is successfully performed for the first time at an 88-nm technology node. The Co-silicided support transistors in the DRAM circuit can be made by using the silicidation-blocking-layer method which keeps the cell array from silicidation. Raised S/D transistors using Si selective epitaxial growth (SEG) demonstrate good short-channel eect (SCE) immunity and a Co-silicided S/D in the support transistors exhibits an excellent current driving capability and reduced S/D sheet resistance, even for very small dimensions.

Tribology Characteristics in 200 μm of Hexagonal Array Dimple Pattern

W. S. Choi,Angga S. H.,S. H. Kwon,S. G. Kwon,J. M. Park,J. S. Kim,S. W. Chung,Y. H. Chae 한국트라이볼로지학회 2015 한국트라이볼로지학회지 (Tribol. Lubr.) Vol.31 No.2

This study investigates the effects of a pattern of 200 μm dimples in a hexagonal array on tribological characteristics. A textured surface might reduce the friction coefficient and wear caused by third-body abrasion and thus improve the tribological performance. There are three friction conditions based on the Stribeck curve: boundary friction, mixed friction, and fluid friction conditions. In this experiment, we investigate the friction characteristics by carrying out the friction tests at sliding speeds ranging from 0.06 to 0.34 m/s and normal load ranging from 10 to 100 N. We create dimple surfaces for texturing by using the photolithography method. There are three kinds of specimens with different dimple densities ranging from 10% to 30%. The dimple density on the surface area is the one of the important factors affecting friction characteristics. Friction coefficient generally decreases with an increase in the velocity and load, indicating that the lubrication regime changes depending on the load and velocity. The fluid friction regime is fully developed, as indicated by the duty number graph. Fluid friction occurs at a velocity of 0.14-0.26 m/s. The best performance is seen at 10% dimple density and 200 μm dimple circle in the hexagonal array.