• Title/Summary/Keyword: Hale

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Simulation of Small Carbon Clusters(I) -Geometries and Energies of $C_2$-C$_5$ - (탄소 클러스터들에 관한 시뮬레이션(I) -C$_2$-C$_5$ 의 구조와 에너지-)

  • Lee, Chong-Mu
    • Korean Journal of Materials Research
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    • v.1 no.3
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    • pp.139-144
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    • 1991
  • The geometries and energies of $C_2-C_5$ clusters have been calculated using simple semiempirical potential energy functions. The results of the calculations show that the most stable structure of the $C_2-C_5$ clusters is linear and that not only the rhombic $C_4$ but also the Y-shaped $C_4$ hale similar energy to the linear $C_4$.

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Histochemical Observation on the Epithelial Tissue in the Wound Healing (창상치유시 상피조직에 관한 조직화학적 관찰)

  • Ko, Jea-Seoung
    • The Journal of the Korean dental association
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    • v.11 no.12
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    • pp.783-786
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    • 1973
  • The healing response may very with the tissue, the site and the degree of wound. the author observed histochemically the epithelial regeneration in the har palate wound of healthy male albino rats, varying in age from 120 to 150 days, and weighing about 100 gm. The deep wounds were made antero-posterior linealy by surgical knife to the depth of bone level. They were sacrified by ether anesthesia on 1, 2, 4, 7, 10 and 14 days after wounding. the staining methods used were Mcmanus' PAS reaction, Mowry's modification of the Hale reaction employing Muller's colloidal iron reagent, alloxan-Schiff reaction and hematoxylin-eosin stain. The results were as follows : 1. In the wound healing of hard palate, the epithelium had marked PAS positive reaction in the granular and the prickle cell layers on the from 2nd to 7th day. 2. Alloxan-Schiff reactions of regenerated epithelium were slightly increased on 7th day.

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A STUDY ON THE LOW REYNOLDS NUMBER AIRFOILS FOR THE DESIGN OF THREE DIMENSIONAL WING (3차원 날개 설계를 위한 저레이놀즈수 에어포일에 대한 연구)

  • Jung, K.J.;Lee, J.;Kwon, J.H.;Kang, I.M.
    • 한국전산유체공학회:학술대회논문집
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    • 2009.04a
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    • pp.90-96
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    • 2009
  • In this study, a generic airfoil designed by the inverse method was evaluated with several candidate airfoils as a first step. Each airfoil was compared with respect to aerodynamic performance to meet the requirement of HALE(high altitude long endurance) aircraft. The second step was to optimize the candidate airfoil using the couple of optimization formulations to down select an optimum airfoil. For the analysis of low Reynolds number 2D flow, Drela's MSES was used. After comparing the aerodynamic results, the best airfoil was chosen to construct the baseline 3D wing. The Navier-Stokes code was used to evaluate the overall aerodynamic performance of designed wing with other wings. The results show that the designed wing has the best performance compared with other wings.

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Aerothermoelastic Analysis of Cylindrical Piezolaminated Shells Based on Multi-field Layerwise Theory (다분야 층별 이론에 기초한 원통형 압전적층 쉘의 공력열탄성학적 해석)

  • Oh, Il-Kwon;Shin, Won-Ho;Lee, In
    • Composites Research
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    • v.15 no.3
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    • pp.52-61
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    • 2002
  • For the aerothermoelastic analysis of cylindrical piezolaminated shells, geometrically nonlinear finite elements based on the multi-field layerwise theory hale been developed. Applying a Han Krumhaar's supersonic piston theory, supersonic flutter analyses are performed for the cylindrical piezolaminted shells subject to thermal stresses and deformations. The possibility to increase flutter boundary and reduce thermoelastic deformations of piezolaminated panels is examined using piezoelectric actuations. Results show that active piezoelectric actuations can effectively increase the critical aerodynamic pressure by retarding the coalescence of flutter modes and compensating thermal stresses.

Effect of Slag Grade and Cement Source on the Properties of Concrete

  • Becknell, Natalie Peterson;Hale, William Micah
    • International Journal of Concrete Structures and Materials
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    • v.5 no.2
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    • pp.119-123
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    • 2011
  • Presented in the paper are findings of a project that examined the effect of slag grade and cement source on the performance of concrete mixtures. Slag cement contents were 20, 40, and 60 percent of the total cementitious material content. Two grades of slag cement were examined (Gr. 100 and Gr. 120) along with two sources of Type I cement. Compressive strength, durability, and permeability were measured. The results showed that the cement source affected the early age strength of the mixtures. At 28 days of age, mixtures containing Gr. 120 slag cement had higher compressive strengths than mixtures containing Gr. 100 slag cement, but by 90 days of age, the trend reversed. As for the chloride ion penetrability, mixtures cast with Gr. 100 slag cement passed fewer coulombs at 28 and 90 days of age than similar mixtures containing Gr. 120 slag. Mixtures containing Gr. 120 slag had the greatest durability factors.

Cluster Analysis on the Distribution of Lichens in the Mt. Hanra (漢拏山 地依植物의 分布에 關한 集落分析)

  • Park Seung-Tai;Du-Mun Choe
    • The Korean Journal of Ecology
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    • v.7 no.3
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    • pp.119-131
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    • 1983
  • The cluster analysis on the distribution of epiphytic lichens on the north, south, east and west slope of Mt. Hanra was carried out by three methods, sum of square algorithm (SSA), prinicipal component analysis (PCA) and multidimensional scaling method(MDS). Analysis of concentration (AOC) was used for the comparison between the lichen communities of north and south slope. The lichen species was identified 35 species by Hale and Culberson technique. The classification of sites by SSA method was divided into two areas in four slopes, and that of species by SSA, PCA and MDS methods was classified into three clusters in east slope, four clusters in south and west slope, and there clusters in north slope. The comparison between north and south slope of the distribution of lichens indicates that loight elevation of north slope (NH; 1600m~1900m) was similar to that of relative low elevation of south slope (SL; 1000m~1300m). The genus lichen, Anaptychia, Parmelia, Lobaria and peltigera was found as the dominant genus in both slopes.

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A Study on the NO$_2$Gas-Detection characteristics of the Copper-tetra-tert-butylphthalocyanine(CuTBP) LB Film depending on the density and temperatures (Copper-tetra-tert-butylphthalocyanine(CuTBP) LB막의 온도와 농도에 따른 NO$_2$가스 탐지 특성)

  • 한영재;이창희;하윤경;김태완;김정수
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1995.11a
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    • pp.179-182
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    • 1995
  • The NO$_2$gas-detection characteristics were investigated using the functional organic Langmuir-Blodgett(LB) films of Copper-tetra-tert-butylphthalocyanine(CuTBP). The optimum conditions for a film deposition were obtained through a study of $\pi$-A isotherms, and the deposited film status was confirmed by the ellipsometry measurements. It was found that at room temperature there are increments of electrical conductivities by 40 times, 25 seconds of response time and 40 seconds of response time when the films were exposed to the 200ppm NO$_2$gases. We hale observed an increase of the electrical conductivities as the density of NO2 gas increases.

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A Study on DIBL Characteristics in Deep Sub-Half Micron PMOSFETs (Deep Sub-Half Micron PMOSFETs의 DIBL 특성에 관한 연구)

  • 신희갑;류찬영;이철인;서용진;김태형;장의구
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1995.11a
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    • pp.232-235
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    • 1995
  • To improve the DIBL characteristics of deep sub micron BC PMOSFETs, the methods of DCI(Deep Channel Implantation) and Hale Implantation have been reported. In this study, using the process simulator TSUPREM4, we simulated the 0.25$\mu\textrm{m}$ and 0.45$\mu\textrm{m}$ gate length BC PMOSFETs applying the both methods to improve the DIBL characteristics, and their electric characteristics were compared to find the mothod suitable far deep sub-half micron BC PMOSFETs, using the device simulator MEDICI. So we found out that the method of Halo Implantation could be applied to deep sub-half micron BC PMOSFETs for 255 Mbit DRAM.

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A Comparison between the Thermomechanical and Structural Changes in Textured PET Yarns after Superheated Steam and Dry Heat Treatment

  • Karakas, Hale-Canbaz
    • Fibers and Polymers
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    • v.5 no.1
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    • pp.19-24
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    • 2004
  • PET yarns textured at different texturing conditions were treated with superheated steam or dry heat at different temperatures for different times. The effects of the treatment conditions on the thermomechanical and structural changes of the yarn were examined by shrinkage, X-ray diffraction and birefringence measurements. With increase in superheated steam temperature, the crystalline orientation factor and birefringence decreased, whereas crystal size increased. Dry heat treatment had a smaller effect on shrinkage and structural properties in comparison with superheated steam treatment. The additional shrinkage after texturing process was investigated. The effect of heat-setting in both media was more significant at $200^{\circ}C$. The time dependence of the properties was not linear.

An Efficient If Routing Lookup by Using Routing Interval

  • Wang, Pi-Chung;Chan, Chia-Tai;Chen, Yaw-Chung
    • Journal of Communications and Networks
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    • v.3 no.4
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    • pp.374-382
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    • 2001
  • Nowadays, the commonly used table lookup scheme for IP routing is based on the sc-called classless interdomain routing (CIDR). With CIDR, routers must find out the best matching prefix (BMP) for IP packets forwarding, this complicates the IP lookup. Currently, this process is mainly performed in software and several schemes hale been proposed for hardware implementation. Since the IP lookup performance is a major design issue for the new generation routers, in this article we investigate the properties of the routing table and present a new approach for IP lookups, our approach is not based Gn BMP and significantly reduces the complexity, thus the computation cast of existing schemes can be significantly reduced. We also propose an efficient IP lookup algorithm, with which we improve the binary search on prefixes to 30 millions of packets per second (MPPS) and 5,000 route updates/s under the same experiment setup with an even larger routing table.

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