• Title/Summary/Keyword: 평행관

Search Result 80, Processing Time 0.029 seconds

Fabrication of the Silicon Nano Structure applicable to Non-volatile Memory Device using Block Copolymer (비휘발성 메모리 소자 응용을 위한 블록 공중합체를 이용한 실리콘 나노 구조 제작)

  • Jung, Sung-Wook;Kim, Hyun-Min;Park, Dae-Ho;Sohn, Byeong-Hyeok;Jung, Jin-Chul;Zin, Wang-Cheol;Parm, I.O.;Yi, Jun-Sin
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2005.07a
    • /
    • pp.95-96
    • /
    • 2005
  • 나노 구조 제작을 위한 다양한 시도 중 블록 공중합체를 이용한 방법은 현재 활발한 연구가 진행되고 있는 분야이다. 본 연구에서는 비휘발성 메모리 소자의 용량 증가를 위하여 블록 공중합체 박막을 나노 마스크로 이용하고, 평행판헝 반응관 내에서 반응성 이온 에칭을 사용하여 나노 구조의 표면을 제작하였다. 에칭동안에 나노 마스크로서 사용할 블록 공중합체 박막은 PS-b-PMMA를 이용하여 제작하였고, UV를 주사하여 PMMA를 제거하고 수직적인 나노 흩을 구성하여 나노 패터닝이 가능하도록 하였다. 실험을 통하여 매우 균일한 나노 바늘 형태의 구조를 생성할 수 있으며, 반응기체와 유량의 조절을 통하여 다양한 표면 구조를 확인할 수 있었다. 블록 공중합체는 나노 마스크로서 뛰어난 기능을 나타내며, 이를 이용하여 나노 사이즈의 패터닝이 가능하고, 표면적 증가를 통하여 비휘발성 메모리 소자의 용량 증가에 기여할 수 있다.

  • PDF

Optimization of Water Reuse System under Uncertainty (불확실성을 고려한 하수처리수 재이용 관로의 최적화)

  • Chung, Gun-Hui;Kim, Tae-Woong;Lee, Jeong-Ho;Kim, Joong-Hoon
    • Journal of Korea Water Resources Association
    • /
    • v.43 no.2
    • /
    • pp.131-138
    • /
    • 2010
  • Due to the increased water demand and severe drought as an effect of the global warming, the effluent from wastewater treatment plants becomes considered as an alternative water source to supply agricultural, industrial, and public (gardening) water demand. The effluent from the wastewater treatment plant is a sustainable water source because of its good quality and stable amount of water discharge. In this study, the water reuse system was developed to minimize total construction cost to cope with the uncertain water demand in future using two-stage stochastic linear programming with binary variables. The pipes in the water reuse network were constructed in two stages of which in the first stage, the water demands of users are assumed to be known, while the water demands in the second stage have uncertainty in the predicted value. However, the water reuse system has to be designed now when the future water demands are not known precisely. Therefore, the construction of a pipe parallel with the existing one was allowed to meet the increased water demands in the second stage. As a result, the trade-off of construction costs between a pipe with large diameter and two pipes having small diameters was evaluated and the optimal solution was found. Three scenarios for the future water demand were selected and a hypothetical water reuse network considering the uncertainties was optimized. The results provide the information about the economies of scale in the water reuse network and the long range water supply plan.

The Ultrastructure of the Cutaneous Pigment Cells in the Frog, Rana nigromaculata Hallowell, during Hibernating Phases (동면기 개구리 (Rana nigromaculata) 피부색소세포의 미세구조)

  • 김한화;지영득;문영화
    • The Korean Journal of Zoology
    • /
    • v.26 no.4
    • /
    • pp.271-282
    • /
    • 1983
  • The authors observed the ultrastructure of the pigment cells of the frog, Rana nigromaculata Hallowell, during the hibernation. The specimens from the skin were fixed in 2.5% glutaraldehyde-paraform-aldehyde fixative in phosphate buffer at pH 7.2 prior to fixation in 2% osimium tetroxide, dehydrated in graded ethanol and acetone, embedded in Epon 812 mixture, and sectioned with LKB-ultramicrotome. the ultrathin sections were contrasted with uranyl acetate and lead citrate and observed with a JEOL-100B electron microscope. The results were as follows. In hibernating phase, pigment cells of the frog were consisted of the three kinds of chromatophores (xanthophore, iridophore and melanophore) in their dorsal skin. The traits of these cells were as follows. 1. Xanthophores A. Xanthophores were filled with pterinosomes and carotenoid vesicles. Many ribosomes, a few mitochondria and glycogen particles were dispersed in the cytoplasm. B. Pterinosomes were spherical or ellipsoidal in shape. They were divided into 6 types (type I, type II, type III, type IV, type V, type VI pterinosomes) by the their inner structure and especially, type I, type II, type III pterinosomes were well developed.

  • PDF

The Low and Static Magnetic Field Effects on the Motion of Biomolecule Sanals Inside the Primo Vascular System (낮은 정자기장 하에서 프리모 시스템 산알의 운동특성 연구)

  • Lee, Sang-Suk;Soh, Kwang-Sup
    • Journal of the Korean Magnetics Society
    • /
    • v.21 no.6
    • /
    • pp.219-224
    • /
    • 2011
  • The motion features of sanals inside of the primo vascular system (PVS), that is so-called the Kyungrak system, are investigated under a low static magnetic field by using the anatomy technology and optical microscope. The sanals with a size of about 1 selected and separated from the primo vessel and node of the real PVS inside of the surface of the internal organs are observed from rabbits' abdominal wall and dipped with PBS liquid inside of petri dish. The sanal's moving velocity along the direction of magnetic field (xdirection) and perpendicular to the direction of magnetic field (y-direction) under the low magnetic field of 0 Oe, 20 Oe, 40 Oe, 60 Oe, and 80 Oe, respectively, is observed below a internal temperature of $38^{\circ}C$. Ten sanals' moving velocities versus magnetic field are shown two differently dominant tendencies with an average velocity of 0.9 pixel/s and a random velocity according to the x-direction and y-direction, respectively. This experimental results imply that the rotating motion of sanal with nuclei DNA composed of many inorganic magnetic materials of Mn and Co is monotonically weakened by the increase of applied magnetic field.

Anatomical and Physical Properties of Pitch Pine (Pinus rigida Miller) - The Characteristics of Stem, Branch, Root and Topwood - (리기다소나무(Pinus rigida Miller)의 목재해부학적(木材解剖學的) 및 물리학적성질(物理學的性質)에 관(關)한 연구(硏究) - 간(幹), 지(枝), 근(根), 초두목(梢頭木)의 특성(特性)을 중심(中心)으로 -)

  • Lee, Phil Woo
    • Journal of Korean Society of Forest Science
    • /
    • v.16 no.1
    • /
    • pp.33-62
    • /
    • 1972
  • Pitch pine (Pinus rigida Miller) in Korea has become one of the major silvicultural species for many years since it was introduced from the United States of America in 1907. To attain the more rational wood utilization basical researches on wood properties are primarily needed, since large scale of timber production from Pitch Pine trees has now been accomplishing in the forested areast hroughout the country. Under the circumustances, this experiment was carried out to study the wood anatomical, physical and mechanical properties of Pitch Pine grown in the country. Materials used in this study had been prepared by cutting the selected pitch pine trees from the Seoul National University Forests located in Suwon. To obtain and compare the anatomical and physical properties of the different parts of tree such as stem, branch, top and rootwood, this study had been divided into two categories (anatomical and physical). For the anatomical study macroscopical and microscopical features such as annual ring, intercellular cannal, ray, tracheid, ray trachid, ray parenchyma cell and pit etc. were observed and measured by the different parts (stem, branch, root and topwood) of tree. For the physical and mechanical properties the moisture content of geen wood, wood specific gravity, shrinkage, compression parallel to the grain, tension parallel and perpendicular to the grain, radial and tangential shear, bending, cleavage and hardness wree tested. According to the results this study may be concluded as follows: 1. The most important comparable features in general properties of wood among the different parts of tree were distinctness and width of annual ring, transition from spring to summerwood, wood color, odor and grain etc. In microscopical features the sizes of structural elements of wood were comparable features among the parts of tree. Among their features, length, width and thickness of tracheids, resin ducts and ray structures were most important. 2. In microscopical features among the different parts of tree stem and topwood were shown simillar reults in tissues. However in rootwood compared with other parts on the tangential surface distinctly larger ray structures were observed and measured. The maximum size of unseriate ray was attained to 27 cell ($550{\mu}$) height in length and 35 microns in width. Fusiform rays were formed occasionally the connected ray which contain one or several horizontal cannals. Branchwood was shown the same features like stemwood but the measured values were very low in comparing with other parts of tree. 3. Trachid length measured among the different parts of tree were shown largest in stem and shortest in branchwood. In comparing the tracheid length among the parts the differences were not shown only between stem and rootwood, but shown between all other parts of tree. Trachid diameters were shown widest in rootwood and narrowest in branchwood, and the differences among the different parts were not realized. Wall thickness were shown largest value in rootwood and smallest in branchwood, and the differences were shown between root and top or branchwood, and between stem and branch or top wood, but not shown between other parts of tree. 4. Moisture contents of green wood were shown highest in topwood and lowest in heartwood of stem. The differences among the different parts were recognized between top or heartwood and other parts of tree, but not between root and branchwood or root and sapwood. 5. Wood specific gravities were shown highest in stem and next order root and branchwood, but lowest in topwood. The differences were shown clearly between stemwood and other parts of tree, but not root and branchwood. However the significant difference is realized as most lowest value in topwood. 6. In compression strength parallel to the grain compared among the different parts of tree at the 14 percent of moisture content, highest strength was appeared in stem, next order branch and rootwood, but lowest in topwood. 7. In bending strength compared among the different parts of tree at the 14 percent of moisture content clearly highest strength was shown in branchwood, next order stem and root, but lowest in topwood. Though the branchwood has lower specific gravity than stemwood it was shown clearly high bending strength.

  • PDF

A Study on the Plane Turbulent Offset Jet (평면 난류 오프셋 제트에 관한 연구)

  • 유정열;강신형;채승기;좌성훈
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.10 no.3
    • /
    • pp.357-366
    • /
    • 1986
  • The flow characteristics of two-dimensional turbulent offset jet which is discharged parallel to a solid wall has been studied experimentally and numerically. In the experiment, 3-hole pitot tube and 2 channel constant temperature hot-wire anemometer are used to measure local mean velocity, turbulence intensity and Reynolds stress while scannivalve is used to measure the wall pressure distribution. It is confirmed experimentally that local mean velocity is closely related to wall pressure distribution. It is also verified that for large Reynolds numbers and fixed step height there exists a similarity in the distribution of wall pressure coefficient. The maximum values of turbulence intensity occur in the top and bottom mixing layers and the magnitude of Reynolds stress becomes large in the lower mixing layer than in the top mixing layer due to the effect of streamline curvature and entrainment. In the numerical analysis, standard k-.epsilon. model based on eddy viscosity model and Leschziner and Rodi model based on algebraic stress model are adopted. The numerical analyses predict shorter reattachment lengths than the experiment, and this difference is judged to be due mainly to the problem of turbulence model constants and numerical algorithm. This also causes the inconsistency between the two results for other turbulence quantities in the recirculation region and impingement region, which constitutes a subject of a continued future study.

Isolation of Brucella Suis from Aborted Fetus of a Dog (유산견(流産犬) 태아(胎兒)로부터 Brucella suis의 분리(分離))

  • Tak, Ryun-Bin;Chun, Do-Ki
    • The Journal of the Korean Society for Microbiology
    • /
    • v.7 no.1
    • /
    • pp.17-20
    • /
    • 1972
  • A strain of Brucella showing the characteristics of Br. suis was isolated from a 55 day-old aborated fetus of a German Shepherd and the cause of the abortion was considered due to brucellosis. A considerable number of dog sera collected at the slaughter house in Taegu city showed antibody titers of 1:80 or more to Br. suis, and serum from the aborted dog 1:320 to Br. suis in titer.

  • PDF

Studies on the Aging of Bovine Muscle at Adding the Proteolytic Enzyme -VII. Studies on the Histological Observation of Bovine Muscle Treated with Papain- (단백질(蛋白質) 분해효소(分解酵素) 첨가시(添加時) 우육(牛肉)의 숙성(夙成)에 관(關)한 연구(硏究) -VII. Papain 처리(處理) 우육(牛肉)의 조직학적(組織學的) 고찰(考察)-)

  • Yoon, Jung-Eui
    • Korean Journal of Food Science and Technology
    • /
    • v.9 no.4
    • /
    • pp.271-276
    • /
    • 1977
  • Treating with step concentration of papain, round mucle of Korean cattle were cut in longitudinal and cross section and stained. Collagenous fibre and elastic fibre of its connective tissue were observed microscopically. The results were as follows: 1) In proportion to the increase of enzyme concentration amorphous bundle of collagenous fibre were loosed gradually and destroyed in the long run and besides the property of this fibre stained became remarkably weak. 2) Elastic fibre was paralleled to muscle fibre and in proportion to the increase of enzyme concentration, it was lost elasticity, loosed, straightened and broken remarkably to pieces. 3) Histological variation of collagenous fibre and elastic fibre treated with enzyme was more remarkable than control.

  • PDF

Studies on Wood Quality of Pinus koraiensis Sieb. et Zucc. (II) -On the Gross Structural Features of Stem - (잣나무의 재질(材質)에 관(關)한 연구(硏究) (제(第)2보(報)) -수간(樹幹)의 구조적(構造的) 형질(形質)-)

  • Lee, Won Yong
    • Journal of Korean Society of Forest Science
    • /
    • v.17 no.1
    • /
    • pp.17-22
    • /
    • 1973
  • A study on the wood quality from planted Pinus koraiensis Sieb. et Zucc. has been undertaken by the University Forest in order to gain results of the gross structural features of stem. For this study some groups of trees were felled and several characteristics such as the degree of stem, slenderness, eccentric growth, heartwood diameter, height of butt sweep and butt-swell were analyzed. The results of the study are as follows. 1) The relation between diameter of log and its height in sample trees are nearly parallel to each other. But their degrees of slenderness in logs cut from intermediate and codominant trees are some what gentle as compared with that of logs from dominant tree. 2) The eccentric growth at transverse section of sample trees is generally decreased with the increase of tree height on all sample trees. 3) On the eccentric growth at transverse section of tree, a rather distinct tendency was noticed that all of sample trees showed the direction of eccentric growth in $R_2$ side. 4) Heartwood diameter appeares to become larger as tree growth decrease under same diameter of logs and log diameter in which heartwood appeares is larger in rapid growth rate trees. 5) The maximum height of butt-sweep generally shows that the larger the breast height diameter of tree is, the smaller its height becomes. On the contrary it was noticed that the larger the breast height diameter of trees, the higher the maximum height of butt-swell became. The direction of butt-sweep and butt-swell were shown in $R_1$ side in all sample trees.

  • PDF

Development of Tomographic Scan Method for Industrial Plants (산업공정반응기의 감마선 전산 단층촬영기술 개발)

  • Kim, Jong-Bum;Jung, Sung-Hee;Moon, Jin-Ho;Kwon, Taek-Yong;Cho, Gyu-Seong
    • Journal of the Korean Society for Nondestructive Testing
    • /
    • v.30 no.1
    • /
    • pp.20-30
    • /
    • 2010
  • In this paper, a new tomographic scan method with fixed installed detectors and rotating source from gamma projector was presented to diagnose the industrial plants which were impossible to be examined by conventional tomographic systems. Weight matrix calculation method which was suitable for volumetric detector and statistical iterative reconstruction method were applied for reconstructing the simulation and experimental data. Monte Carlo simulations had been performed for two kinds of phantoms. Lab scale experiment with a same condition as one of phantoms, had been carried out. Simulation results showed that reconstruction from photopeak counting measurement gave the better results than from the gross counting measurement although photopeak counting measurement had large statistical errors. Experimental data showed the similar result as Monte Carlo simulation. Those results appeared to be promising for industrial tomographic applications, especially for petrochemical industries.