• Title/Summary/Keyword: Reinforcing

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Effect of Acupuncture on Behavior and Dopamine Release in the Nucleus Accumbens in rats Sensitized to Morphine (몰핀 투여로 민감화된 실험동물의 행동 및 뇌 측핵의 도파민 유리에 대한 침 효과)

  • Lyu Yeoung Su
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.2
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    • pp.510-517
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    • 2003
  • Studies have shown that both the psychomotor stimulant effects and rewarding properties of addictive drugs, including morphine, are sensitized by repeated drug administration and it is suggested that both of these effects are mediated by the same or closely overlapping dopamine systems. Specifically, the mesolimbic dopamine system has been implicated in the reinforcing and sensitizing properties of morphine. In oriental medicine, Shenmen (HT7) point on the heart channel has been used to treat mental and psychosomatic disorders. This study was designed to investigate the effect of acupuncture on acute and repeated morphine-induced changes in extracellular dopamine levels using in vivo microdialysis and morphine-induced behavioral changes. In the morphine sensitization experiment, male Sprague-Dawley rats were treated twice a day for three days with increasing doses of morphine (10, 20 and 40 mg/kg, s.c.) or with saline. After 15 days of withdrawal, rats were challenged with morphine hydrochloride (5 mg/kg, s.c.). Acupuncture was applied at bilateral Shenmen (HT7) points for 1 min after the morphine challenge. In the acute experiment, rats also received acupuncture for 1 min after an injection of morphine hydrochloride (5 mg/kg, s.c.). Results showed that acupuncture at the specific acupoint HT7, but not at control points (tail) significantly decreased both dopamine release and behavior induced by a systemic morphine challenge or a single sc morphine injection in the acute animals. These results suggest that reduction in sensitization may be one mechanism whereby acupuncture alleviates morphine craving in addicts.

Manufacturing of High Water-Resistant Particleboard by Combining Use of Urea Resin and EMDI Resin (요소수지와 EMDI수지의 복합이용에 의한 고내수정 파티클보드의 제조)

  • Park, Jong-Young
    • Journal of the Korean Wood Science and Technology
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    • v.26 no.1
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    • pp.97-105
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    • 1998
  • This study examined the combined using effects of urea-formaldehyde (UF) resin and emulsifiable methylene diphyenyl diisocyanate (EMDI) resin to overcome performance limit of three-layer particleboards commonly made by UF resin. Two adhesive adding methods were applied with three types of resin combination system to each layer of particleboards. The one was simultaneously spreading method with emulsified compound resin (UF and EMDI) while the other was separately spreading method with unemulsified EMDI resin after UF resin spreading. The performance of particleboards bonded with 2% EMDI resin to the inner layers(IL) were similar to that of controls bonded with 8% UF resin. In the case of the emulsified compound resin application to the all layers of particleboards, there were marked reinforcing effects of EMDI resin, although a small amount of EMDI resin was mixed with UF resin. Especially bending MOR after 24 hours cold water-immersion and thickness swelling after 2 hours hot water-immersion of compound resin-bonded particleboards were remarkably different from those of pure UF resin-bonded particleboards. It was found that separately spreading method with unemulsified EMDI resin was more effective than simultaneously spreading method with emulsified compound resin to sustain the internal bond strength of particleboards after 24 hours cold water-immersion. In the resin combination systems to outer layers/inner layers of particleboards, water resistance and strength properties were superior in order of UF+EMDI/UF+EMDI > UF/UF+EMDI > UF/UF. And water resistance of particleboards was greatly dependent upon EMDI resin level in any adhesive adding method.

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A Study on the Restoration of Renaissance Costume (16세기(世紀) Renaissance시대(時代)의 복식분석(服飾分析)과 재현(再現))

  • Mun, Yun-Kyeong;Lee, Soon-Hong
    • Journal of Fashion Business
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    • v.7 no.4
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    • pp.1-16
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    • 2003
  • Nowadays, retro to the past fashion is appeared just as often as new challenge and trial. The style of Renaissance Era is the most often revival theme for contemporary fashion. So, this study was focused on 16C of Renaissance costume. It is investigated the characteristics of Renaissance costume through referring the literature to be able to restore the past costume as through as possible with the object of building database for developing new design. This study is done in two different ways at the same time, direct study to restore and indirect study to refer. Direct one is of the past costume as thoroughas possible based on referring to the originals. The other is referring the costume historical literature The costumes to restore is chosen among 16C famous pictures on the basis of how much they can show the typical chracteristics of 16C costume. Materials including textiles and ornaments which are necessarily to restore were shopped in Dongdeamoon Market. Some materials had a problem to get exactly the same one in Seoul on 21C. After visiting imes, the materials is chosen as similar as originals. Three sets of costume were restored on the basis of referring "Pattern of Fashion" written by Janet Arnold. The costumes were restored by reinforcing bodice based on the size of waist and in every three works. The way of sewing is based on hand sewing for details and machin-sewing for seam. Quilting intl lining is uwed giving the fabric stiffness to maintain the form from the heavy padding. Also the part of piles on margins is used darts instead of gather, because of reducing bulkiness of seam. General closing methods are hook and eyes, and lacing with points.

Dynamic Characteristics of Reinforced concrete axisymmetric shell with shape imperfection (형상불완전을 갖는 철근 콘크리트 축대칭 쉘의 동적 특성)

  • 조진구
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.42 no.5
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    • pp.151-159
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    • 2000
  • Dynamic loading of structures often causes excursions of stresses will into the inelastic range and the influence of geometry changes on the response is also significant in may cases. In general , the shell structures designed according to quasi-Static analysis may collapse under condition of dynamic loading. Therefore, for a more realistic prediction on the lad carrying capacity of these shell. both material and geometric nonlinear effects should be considered. In this study , the material nonlinearity effect on the dynamic response is formulated by the elasto-viscoplastic model highly corresponding to the real behavior of the material. Also, the geometrically nonlinear behavior is taken into account using a Total Lagrangian formulation. the reinforcing bars are modeled by the equivalent steel layer at the location of reinforcements, and Von Mises yield criteria is adopted for the steel layer behavior. Also, Drucker-Prager yield criteria is applied for the behavior of concrete. the shape imperfection of dome is assumed as 'dimple type' which can be expressed Wd1=Wd0(1-(r-a)m)n while the shape imperfection of wall is assumed as sinusoidal curve which is Wwi =Wwo sin(n $\pi$y/l). In numerical test, three cases of shape imperfection of 0.0 -5.0cm(opposite direction to loading ; inner shape imperfection)and 5cm (direction to loading : outward shape imperfection) and thickness of steel layer determined by steel ratio of 0,3, and 5% were analyzed. The effect of shape imperfection and steel ratio and behavior characteristics of perfect shape shell and imperfect shape shell are identified through analysis of above mentioned numerical test. Dynamic behaviors of dome and wall according toe combination of shape imperfection and steel ratio are also discussed in this paper.

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Flexural Capacity of the Profiled Steel Composite Beams -Deep Deck Plate- (강판성형 합성보의 휨성능 평가 -춤이 깊은 합성데크-)

  • Heo, Byung Wook;Kwak, Myong Keun;Bae, Kyu Woong;Jeong, Sang Min
    • Journal of Korean Society of Steel Construction
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    • v.19 no.3
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    • pp.247-258
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    • 2007
  • This paper describes the results of an experimental study on the new type of encased composite beams that use deep deck plates, which could reduce the story height of buildings by controlling the bottom flange of steel beams. The profiled steel beam was thus developed. It was advantageous to the long span of the buildings. Seven full-scale specimens were constructed, and simply supported bending tests were conducted on the encased composite beams with different steel plate thicknesses, with and without shear studs, reinforcing bars, and web openings. The test results showed that the encased composite beams that were developed in this study had sufficient composite action without additional shear connectors due to their inherent shear-bond effects between the steel beams and concrete.

An Experimental Study on Flexural Strength of Modular Composite profiled Beams (휨 보강된 모듈단면 합성 프로파일보의 휨 내력에 관한 실험적 연구)

  • Ahn, Hyung Joon;Ryu, Soo Hyun
    • Journal of Korean Society of Steel Construction
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    • v.19 no.3
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    • pp.323-333
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    • 2007
  • This paper presents a study that attempted to improve the site applicability of profile sheets and check the effects of bending reinforcement in composite profiled beams, and consequently, to suggest an improved modular-type CB2 and two types of bending reinforcement methods. As a result of the reinforcing and reforming modular profiled beam experiment conducted, CBIIshowed an adequate deformation capacity as well as a sufficient plastic plateau at the maximum load and thereafter. For all the specimens, an insignificant modular slip occurred while linear relations were kept constant, at up to approximately 50% of the maximum load and at constant linear relations. The experimental values were very low. Probably, due to the small-scale experiment, the area of the concrete for the concrete filling and covering might have been insufficient, which might have led to the failure to improve the strength. Comparing the results with the standard design stress, all the specimens-except for T16 and B16-indicated more than 0.9. Based on the standard design stress, the reinforced modular profiled beam was consideredto have positive applicability.

A Study on Deformation Capacity of High Strength Steel Beam-to-Column Connections According to Welding Detail at Beam End (보 단부 용접상세에 따른 고강도강 기둥-보 접합부의 변형능력에 관한 연구)

  • Oh, Sang Hoon;Park, Hae Yong
    • Journal of Korean Society of Steel Construction
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    • v.26 no.4
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    • pp.335-348
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    • 2014
  • For high-strength steel, it is difficult to be applied to flexible structural member because it have high yield ratio and low basic material's toughness. One of the great problems when using high-strength steel connections is the brittle fracture at the end of the beam member in common with general mild steel connections. In the cases of mild steel connections, it has be developed that special moment frame connection details by reinforcing structural member or improvement of welding access hole. But, it is incomplete at yet about applicability estimation of high-strength steel connections. This study is the initial step research for the applicability estimation of beam-to-column connections being applied to developed high-strength steel, HSA800. And, it studied about structural performance of the high-strength steel connections according to the details of welding access hole through full-scale test and analytical method.

Dependence Potential of Propofol: Behavioral Pharmacology in Rodents

  • Cha, Hye-Jin;Cha, Ji-Hun;Cho, Hea-Young;Chung, Eun-Yong;Kwon, Kyoung-Jin;Lee, Jun-Yeon;Jeong, Ho-Sang;Kim, Hye-Soo;Chung, Hye-Joo;Kim, Eun-Jung
    • Biomolecules & Therapeutics
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    • v.20 no.2
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    • pp.234-238
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    • 2012
  • Propofol is an anesthetic commonly used to provide sedation or to induce and maintain an anesthetic stated. However, there are reports which indicate propofol may cause psychological dependence or be abused. In the present study, we used various behavioral tests including climbing test, jumping test, conditioned place preference, and self-administration test to assess the dependence potential and abuse liability of propofol compared to a positive control (methamphetamine) or a negative control (saline or intralipid). Among the tests, the conditioned place preference test was conducted with a biased method, and the selfadministration test was performed under a fixed ratio (FR) 1 schedule, 1 h per session. No difference was found in the climbing test and jumping test, but propofol (30 mg/kg, i.p.) increased the rewarding effect in the conditioned place preference test, and it showed a positive reinforcing effect compared to the vehicle. These results indicate that propofol tends to show psychological dependence rather than physical dependence, and it seems not to be related with dopaminergic system.

A Study of Pull-out strength increasement by root of grasses (식물뿌리에 의한 인발력 증가에 관한 연구)

  • Kim, Taegyun;Chae, Soo Kwon;Chun, Seung Hoon;Jeong, Jae Cheol
    • Journal of Wetlands Research
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    • v.14 no.2
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    • pp.199-210
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    • 2012
  • In this study, a pull-out strength increasement of grasses was tested in field and the relationship between a weight of root and pull-out strength was established. The tested grasses were commmon reed, reed and sedge which were cultivated by mat-type like turf and used for revegetation of bank. The shear stress of soil at a section can be discribed as a function of root area and pull-out strength, therefore the result of this study will be used as a foundational data for reinforcing the shear stress of the revegetated bank. The heavier weight of root increased, the stronger shear stress was for all grasses. But the relationship between the weight and the shear stress were different by a kind of grass. The difference between common reed, sedge and reed is due to difference of growth and propagation. A reed propagates by subterranean stem and a root weight and pull-out strength are linearly increased by root and growth of subterranean stem.

Flexural performance of composite walls under out-of-plane loads

  • Sabouri-Ghomi, Saeid;Nasri, Arman;Jahani, Younes;Bhowmick, Anjan K.
    • Steel and Composite Structures
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    • v.34 no.4
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    • pp.525-545
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    • 2020
  • This paper presents a new structural system to use as retaining walls. In civil works, there is a general trend to use traditional reinforced concrete (RC) retaining walls to resist soil pressure. Despite their good resistance, RC retaining walls have some disadvantages such as need for huge temporary formworks, high dense reinforcing, low construction speed, etc. In the present work, a composite wall with only one steel plate (steel-concrete) is proposed to address the disadvantages of the RC walls. In the proposed system, steel plate is utilized not only as tensile reinforcement but also as a permanent formwork for the concrete. In order to evaluate the efficiency of the proposed SC composite system, an experimental program that includes nine SC composite wall specimens is developed. In this experimental study, the effects of different parameters such as distance between shear connectors, length of shear connectors, concrete ultimate strength, use of compressive steel plate and compressive steel reinforcement are investigated. In addition, a 3D finite element (FE) model for SC composite walls is proposed using the finite element program ABAQUS and load-displacement curves from FE analyses were compared against results obtained from physical testing. In all cases, the proposed FE model is reasonably accurate to predict the behavior of SC composite walls under out-of-plane loads. Results from experimental work and numerical study show that the SC composite wall system has high strength and ductile behavior under flexural loads. Furthermore, the design equations based on ACI code for calculating out-ofplate flexural and shear strength of SC composite walls are presented and compared to experimental database.