• Title/Summary/Keyword: pattern reduction ratio

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Effect of Experimental Electrization Stress on the Pathogenesis of Escherichia coli in Mice (실험적 감전 Stress 가 Escherichia coli 감염마우스의 기병에 미치는 영향)

  • Lee, Bang Whan
    • Korean Journal of Veterinary Research
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    • v.13 no.2
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    • pp.119-129
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    • 1973
  • A hypothesis that is a stress condition in animal may cause either enhancement or reduction of the host resistance against microbial infection was experimentally studied. Among of many processes for stress formation an experimental electrization in mice was devised, on the bases of blood picture analysis, and studied the effect of experimental electrization of mice on E. coll infection. The results obtained were as follows. 1. Electrization with ordinary current, A. C. 60 cps., on the path of symmetrical line of both posterior limbs at 20 to 100 volts (less than 10 mA) for 15 to 30 seconds was able to induce a stress reaction in blood pattern without showing any dangers of electrocution, electric burns and other residual signs, and no correlation between blood pattern of the reaction and an amount of current between 20 to 100 volts was observed. As the electrodes, two of 21 gauge hypodermic needles were used, when the electrization each of them were inserted into the center of toe tissue of the both legs. 2. Serum protein fractions following the experimental electrization showed a tendency of a low A/G ratio and a high value of ${\alpha}$-globulin. 3. In the studies on the effect of electrical stress on the pathogenesis of E. coli in mice, a group in which a simultaneous electrization and infection, and a group infected two hours after electrization showed 80 per cent mortality. On the other hand, infection after 20 hours electrization and control groups showed their mortality of 40 and 60 per cent respectively.

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Thermal Expansion Coefficient Measurement of STS430 by Laser Speckle Interferometry (레이저 스페클간섭법에 의한 STS430의 열팽창계수 측정)

  • 김경석;이항서;정현철;양승필
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2004.10a
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    • pp.29-33
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    • 2004
  • This paper presents ESPI system for the measurement of thermal expansion coefficient of STS430 up to 1,000$^{\circ}C$. Existing methods, strain gauge and moire have the limitation of contact to object and do not supply the coefficient up to 800$^{\circ}C$. There needs to measure the data up to 800$^{\circ}C$, because heat resistant materials have high melting temperature up to 1,000$^{\circ}C$. In previous studies related to thermal strain analysis, the quantitative results are not reported by ESPI at high temperature, yet. In-plane ESPI and vacuum chamber for the reduction of air turbulence and oxidation are designed for the measurement of the coefficient up to 1,000$^{\circ}C$and speckle correlation fringe pattern images are processed by commercial image filtering tool-smoothing, thinning and enhancement- to obtain quantitative results, which is compared with references data. The comparison shows two data are agreed within 4.1% blow 600$^{\circ}C$ however, there is some difference up to 600$^{\circ}C$. Also, the incremental ratio of the coefficient is changed up to 800$^{\circ}C$. The reason is the phase transformation of STS430 probably begins at 800$^{\circ}C$.

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Broadband Characterization of Circularly Polarized Waveguide Antennas Using L-Shaped Probe

  • Fukusako, Takeshi
    • Journal of electromagnetic engineering and science
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    • v.17 no.1
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    • pp.1-8
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    • 2017
  • This paper introduces a technique to obtain the broadband characteristics of circularly polarized antennas using an L-shaped probe. A waveguide antenna is suitable for obtaining high gain and handling convenience in some applications; however, the asymmetrical structure of the L-shaped probe results in cross-polarization and frequency dependence on the field distribution of higher-order modes (HOM). In addition to the basic characteristics of a waveguide antenna with an L-shaped probe, the author discusses some techniques to reduce the HOM and cross-polarization. As a result, the 3-dB axial ratio (AR) is obtained with the fundamental mode even when the frequency is expanded to the region for HOM of TM. This reduction is mainly due to the cutoff structure to the TM mode around the short wall of the waveguide. Furthermore, some aperture modification techniques can reduce the cross-polarization in a wide range of angles in the radiation pattern. Such techniques and their mechanisms are discussed in this paper. The obtained performance shows that the proposed antennas have a wide range of angles of 3-dB AR in the radiation pattern, broadband characteristics in impedance and AR, and low variation in group velocity.

Thermal Expansion Coefficient Measurement of STS430 at High Temperature by In-plane ESPI (In-plane ESPI를 이용한 고온에서 STS430의 열팽창계수 측정)

  • 김경석;강기수;장호섭
    • Journal of the Korean Society for Precision Engineering
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    • v.21 no.11
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    • pp.69-74
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    • 2004
  • This paper presents ESPI system for the measurement of thermal expansion coefficient of STS430 up to 1,00$0^{\circ}C$ . Existing methods, strain gauge and moire have the limitation of contact to object and do not supply the coefficient up to 80$0^{\circ}C$ . There needs to measure the data up to 80$0^{\circ}C$, because heat resistant materials have high melting temperature up to 1,000'E In previous studies related to thermal strain analysis, the quantitative results have not reported by ESPI at high temperature, yet. In-plane ESPI and vacuum chamber for the reduction of air turbulence and oxidation are designed for the measurement of the coefficient up to 1,00$0^{\circ}C$ and speckle correlation fringe pattern images are processed by commercial image filtering tool-smoothing, thinning and enhancement- to obtain quantitative results, which is compared with references data. The comparison shows two data are agreed within 4.1% blow $600^{\circ}C$ however, there is some difference up to $600^{\circ}C$. Also, the incremental ratio of the coefficient is changed up to 80$0^{\circ}C$ . The reason is the phase transformation of STS430 probably begins at 80$0^{\circ}C$

Exploring Variables Affecting the Clothing Pressure of Compression Garment -A Comparison of Actual Garments and Virtual Garments- (밀착의복 의복압에 영향을 미치는 변인 탐색 -실제착의와 가상착의 비교-)

  • Nam Yim Kim;Hyojeong Lee
    • Journal of the Korean Society of Clothing and Textiles
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    • v.47 no.6
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    • pp.1080-1095
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    • 2023
  • Three-dimensional virtual fitting has become a trending practice in the fashion industry because of its productivity benefits, allowing garments to be virtually worn by avatar models without physical production. This study analyzed the variables influencing clothing pressure in both real and virtual fittings to expand the potential utility of pressure data derived from the latter. For this purpose, six sets of compression garments were created by combining two types of tricot fabrics and three types of reduced-pattern tops, with the clothing for real and virtual fittings having identical dimensions. Focus was directed to analyzing the correlation among clothing pressure, surface area deformation, and the mechanical properties of the fabrics. In real fittings, clothing pressure was influenced by multiple factors, including garment design, pattern reduction ratio, body shape, and fabric properties, consistent with existing knowledge. In virtual fittings, however, only the digital mechanical characteristics of the fabrics significantly influenced clothing pressure. The findings suggest that a more reliable implementation of clothing pressure in virtual fitting programs necessitates an approach that considers the complex structural information of garments.

Effect of Tocopherol Supplementation on HDL Subfraction and Lipoprotein Pattern in Rabbits Fed High Polyunsaturated Fatty Acids (Tocopherol 첨가가 고불포화지방 식이를 먹인 토끼의 HDL Subfraction과 Lipoprotein Pattern에 미치는 영향)

  • Park, Bum-Soon;Park, Hyun-Suh
    • Journal of Nutrition and Health
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    • v.18 no.1
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    • pp.29-35
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    • 1985
  • This study was designed to evaluate the effects of tocopherol supplementation on serum $HDL_{2}$ and $HDL_{3}$ subfraction and lipoprotein pattern of young rabbits fed the different levels of dietary polyunsaturated fatty acids. White male rabbits with an average bo요 weight of 90kg were assigned into 4 groups : LP( Low PUFA) ; HP( High PUFA) ; LPT( Tocopheror added to LP), HPT(Tocopherol added to HP) by feeding safflower oil or coconut oil at loft( w/w )in addition to thew diet with or without tocopherol for 4 weeks. HDL-Chol and HDL subfractions were determined by polyanionic precipitation method, and the relative amount of lipoprotein by electrophoresis. Serum total cholesterol and TG wer slightly lowered in the group of high PUFA diet and its effect was more in the case of tocopherol supplemented. HDL-Chol level was reduced in the high PUFA diet with or without tocopherol, but overall, HDL-Chol level was not influenced by tocopherol addition and also no significant change in lipoprotein pattern when tocopherol added to the HP diet. $HDL_{2}$ level was increased in HPT group but not in LPT group when tocopherol was added to each HP and LP group, respectively. $HDL_{3}$ levels of both LP and HP groups were reduced with tocopherol supplement, but the reduction was less in the high PUFA groups so that $HDL_{2}$ : $HDL_{3}$ ratio of HP was rather close to that of LP, but it was increased when tocopherol supplemented to the HP diet. Therefore, high PUFA diet could improve the anti atherogenic factor when tocopherol supplemented.

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A Study on Changes of Korean Mortality Pattern, 1930~1980 (한국인의 사망구조 변화에 대한 고찰)

  • 유임숙;김초강;공세권
    • Korea journal of population studies
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    • v.9 no.2
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    • pp.79-92
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    • 1986
  • Death is one of the population movement phenomena used as an important health index in most society. Especially it is regarded as group phenomenon in a specific group rather than individual one and considered important in public health field because the level and cause of death is related to health of public. The auther examined the changes of the Korean mortality pattern to evaluate the status of the Korean public health by studying mortality indicator using the population census and other materials from 1930 to 1980. The results are as follows: First, the Korean crude death rate was reduced to one third in 1980 compared to that in 1930, but the crude birth rate was constant from 1930 to 1960 causing the increase of population. So the population pattern is changing from the classic pyramic shape to bell shape and the dependency ratio was reduced from 78 in 1930 to 61 in 1980. Second, the infant mortality rate decrease rapidly. In 1980 it was one seventh of that in 1930 which was proved by the change of the age-specific death rate curve from U to J shape. Third, the male mortality reduction after the age of forty was much less than that of female, which explained the specific death pattern of high mortality in Korean middle and oldaged males. Fourth, the main cause of death was changed from infectious, parasitic, respiratory and digestive system disease to circulatory of tumorous diseases. Considering the above results, Korean health problem is now changing from the infant infection to geriatric chronic regressive disease. That naturally the direction of health service should be turned from the infant stage maternal and child health to the health problems of old people.

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Characterization of Weathered Zone bearing Corestones through Scale Model Test (실내모형실험에 의한 핵석 풍화대 지반 특성 산정)

  • Woo, Ik
    • The Journal of Engineering Geology
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    • v.17 no.3
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    • pp.435-443
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    • 2007
  • This study shows the prediction of the engineering properties of weathered zone bearing corestones through the engineering geological surveys and the scale model test in the laboratory. The window survey and the observation on the borehole core were peformed on three natural slopes in corestones area in order to analyse the distribution pattern and the geometrical properties of corestones. Natural corestones were crushed and abrased for the scale model test into less than 5 mm in maximum-2mm in average by the scale reduction ratio based on the size of natural corestones and the specimen size. Scale model tests were carried out on soil and plaster model specimens with different corestone content ratio - 0%, 10%, 20%. The direct shear test on soils shows that shear strength is increased by the increase of corestone content ratio. The increase of cohesion is, however, more important factor to the shear strength of soil for 20% corestone content ratio due to interlocking of crushed corestone particles. The plaster model test shows a tendance of increase of UCS and modulus of elasticity with increase of corestone content. The variation ratio of specimen property by change of corestone content ratio in plaster model test was applied to in situ properties in order to estimate the properties of weathered zone bearing corestones. So it could be predicted that the increase of corestone content to 10% and to 20% produce about 18% and 30% UCS's increase respectively.

Experiment Investigation on Fluid Transportation Performance of Propellant Acquisition Vanes in Microgravity Environment

  • Zhuang, Baotang;Li, Yong;Luo, Xianwu;Pan, Halin;Ji, Jingjing
    • International Journal of Fluid Machinery and Systems
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    • v.7 no.1
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    • pp.1-6
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    • 2014
  • The propellant acquisition vane (PAV) is a key part of a vane type surface tension propellant management device (PMD), which can manage the propellant effectively. In the present paper, the fluid transportation behaviors for five PAVs with different sections were investigated by using microgravity drop tower test. Further, numerical simulation for the propellant flow in a PMD under microgravity condition was also carried out based on VOF model, and showed the similar flow pattern for PAVs to the experiment. It is noted that the section geometry of PAVs is one of the main factors affecting the fluid transportation behavior of PMD. PAVs with bottom length ratio of 5/6 and 1/2 have larger propellant transportation velocity. Based on the experiments, there were two stages during the process of propellant transportation under microgravity environment: liquid relocation and steady transportation stage. It is also recognized that there is a linear correlation between liquid transportation velocity and relative time's square root. Those results can not only provide a guideline for optimization of new vane type PMDs, but also are helpful for fluid control applications in space environment.

A Study on the Estimation of Elasto-Plastic Buckling Loads for Sing1e Layer Latticed Domes by Unit Member Modeling Technique. (단위부재 모델화에 따른 단층 래티스 돔의 탄소성 좌골하중의 산정에 관한 연구)

  • 한상을;이상주;유용주;이경수
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1998.10a
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    • pp.290-297
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    • 1998
  • In this paper, we propose to a method to estimate the elasto-plastic buckling for single layer latticed domes. First, we assume that each member consists of the rigid zone and elastic spring at both end joint, the elastic element and three elasto-plastic spring to judge for yeilding the member. Next, the member which has most influence on buckling for structures is determined by a distributed pattern of the strain energy which is calculated through linear eigenvalue analysis. And then, normalized slenderness ratio of the element is derived considering the axial force at elastic buckling load. Later, we execute elasto-plastic nonlinear analysis that based on loading increasement method and displacement increasement method. From this results, we discusses the effect of the joint rigidity and the half open angle $\theta$$_{0}$ on the buckling strength of single layer lattice domes ; (1) how the joint rigidity contributes to the reduction of buckling loads, (2) how the reduction can be interrelated to compressive strength curves in terms of the generalized slenderness for the member most relevant to the overall buckling of domes.s.

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