• 제목/요약/키워드: Joint R&D

검색결과 400건 처리시간 0.042초

고강도 철근 및 고강도 콘크리트를 사용한 보-기둥 접합부의 연성거동 (Ductile Behavior of High Strength Reinforced Concrete Beam-Column Joint)

  • 이정한;유영찬;이원호;정헌수
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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    • pp.537-540
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    • 1999
  • The primary objective of this study is to make a contribution to the construction of 40~60 story R/C high rise building by developing the reinforcing details which can improve the seismic performance of high-strength (f'c=700kg/$\textrm{cm}^2$, fy=4000, 8000kg/$\textrm{cm}^2$) R/C beam-column joints. And the purpose of this study is to investigate experimentally the effect of load history on the total energy dissipation capacity of reinforced concrete flexural members. The reinforcing details which can make beam plastic hinging zones moved and spreaded from the column face is proposed to insure the ductile behavior of high-strength RC beam-column joints. The intermediate reinforcement which is horizontally anchored by interlinking each intermediate reinforcements is proposed and tested to examine the mechanical performance of proposed details. Main variables are the shape of the intermediate reinforcements and yield strength of rebars. From the test results, the newly proposed intermediate reinforcement details can move and spread the beam plastic hinging zone about 1.0d from the column face.

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고강도 철근 및 고강도 콘크리트를 사용한 보-기둥 접합의 비선형 거동 (Inelastic Behavior of High Strength Reinforced Concrete Beam-Column Joint)

  • 이정한;조중현;유영찬;이원호;정헌수
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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    • pp.547-552
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    • 1999
  • The purpose of this study is to make a contribution to the construction of 40∼60 story R/C high rise building by developing the reinforcing details which can improve the seismic performance of high-strength (f'c=700㎏/㎠, fy=4000, 8000㎏/㎠) R/C beam-column joints. The reinforcing details which can make beam plastic hinging zones moved and spreaded from the column face is proposed to insure the ductile behavior of high-strength RC beam-column joints. The intermediate reinforcement which is vertically anchored by interlinking each intermediate reinforcements is proposed and tested to examine the mechanical performance of proposed details. Main variables are the shape of the intermediate reinforcements and yield strength of rebars. From the test results, the newly proposed intermediate reinforcement details can move and spread the beam plastic hinging zone about 1.0d from the column face.

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만성관절염 환자의 건강증진행위와 통증, 자아존중감, 가족지지 및 자기효능감과의 관계 (The Relationship among The Health Promoting Behavior, Pain, Self-esteem, Family Support and Self-efficacy in Patients with Chronic Arthritis)

  • 오현아;김종임
    • 근관절건강학회지
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    • 제11권1호
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    • pp.50-60
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    • 2004
  • Purpose: The purpose of this study was to examine the relationships among the health promoting behavior, pain, self-esteem, family support, self-efficacy in patients with chronic arthritis. Method: The data for this study were collected from February 19, 2003 to April 7, 2003. The subjects were 150 chronic arthritis patients who visited University Hospital in D City. The research instruments used in this study were HPLP II, Visual analogue scale, Self-esteem scale, Family support scale, Self-efficacy scale. In data analysis, SPSS PC ver 10.0 program was utilized and data were analyzed using descriptive statistics and t-test, ANOVA, Multiple Stepwise Regression and Pearson's correlation coefficient. Result: The average score of the pain, self-esteem, family support, self-efficacy, health promoting behavior was 5.38, 3.37, 4.29, 70.30, 2.68, respectively and the variable with the highest degree of it's subscale was interpersonal support(3.08), whereas the one with the lowest degree was exercise(1.66). There was a positive correlation(r=.327, p=.000) between the self-esteem and health promoting behavior. There was a positive correlation(r=.540, p=.000) between the family support and the self-efficacy and health promoting behavior. Family support, self-efficacy and marital status were significant factors to explain a variance of health promoting behavior in patients with chronic arthritis(51.6%). health promoting behavior. There was a positive correlation(r=.477, p= .000) between Conclusion: The health promoting behavior were positively correlated with self-esteem, family support and self-efficacy. These findings help to understand relationships among self-esteem, family support and self-efficacy in chronic arthritis patients. In addition, family support, self-efficacy and marital status were the mainly influencing factors of health promoting behavior. Among these variables family support was the most significant factor to predict a health promoting behavior. According to the results of this study, family support must be considered as a main factor in the nursing strategy for health promoting behavior of chronic arthritis patients.

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Expression of IL-17 Homologs and Their Receptors in the Synovial Cells of Rheumatoid Arthritis Patients

  • Hwang, Sue-Yun;Kim, Ho-Youn
    • Molecules and Cells
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    • 제19권2호
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    • pp.180-184
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    • 2005
  • IL-17 is a major proinflammatory cytokine secreted by activated T-lymphocytes that accumulates in the inflamed joints of rheumatoid arthritis (RA) patients. Additional IL-17-related molecules and their receptors have been discovered and may also contribute to RA pathogenesis. We examined the expression of the prototypic IL-17 (IL-17A) and its homologs, IL-17B-F, by RT-PCR analyses of synovial fluid mononuclear cells (SFMCs) and peripheral blood mononuclear cells (PBMCs) from RA patients. We also tested for induction of the IL-17 receptor homologs upon stimulation of the fibroblast-like synoviocytes (FLSs) of RA patients with IL-17. The patients' SFMCs expressed IL-17C, E and F in addition to IL-17A. As in the case of IL-17, IL-15 appears to be the major inducer of these homologs in RA SFMCs. We detected transcripts of IL-17R, as well as those of IL-17RB, C and D, in the FLSs of RA patients. Whereas IL-17R expression increased upon in vitro stimulation with IL-17, expression of IL-17RB, C and D was unchanged. However the possibility of cross-interaction between other IL-17 homologs and receptor isoforms remains to be investigated. Our data suggest that these additional homologs should also be considered as targets for immune modulation in the treatment of RA joint inflammation.

원심성형 고성능 철근콘크리트 말뚝의 휨 성능 연구 (Flexural Performance of Enhanced Spun High Strength RC Piles)

  • 황훈희;배재현;주상훈;권의성
    • 한국안전학회지
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    • 제33권3호
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    • pp.52-57
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    • 2018
  • The pile construction method is changing from the pile driving operation to the injected precast pile method. It is to prevent environmental damage and to minimize complaints caused by noise. Therefore, economic alternatives optimized for the injected precast pile method are required. In this study, the enhanced spun reinforced concrete piles manufactured by high strength materials were proposed. Experimental tests were conducted to evaluate their structural safety and nonlinear finite element analysis was performed to improve the reliability of experimental results. The experimental results and the analytical results were in good agreement with each other and the proposed enhanced spun reinforced concrete pile has better performance than that required by the design. However, the performance of the joint using the existing method used in the PHC pile was considered to be insufficient.

The Effect of Technology Spillover on Business Efficiency: A Case Study in Vietnam

  • PHUNG, Mai Lan;HOANG, Vu Hiep;NGUYEN, Thi Thanh Huyen;PHAM, Thi Thanh Van;TRAN, Viet Tien;HOANG, Van Hoa
    • The Journal of Asian Finance, Economics and Business
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    • 제8권5호
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    • pp.355-364
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    • 2021
  • The main objective of this study is to examine the interactive effect of technology spillover channels on business efficiency within the case study of manufacturing industry of Vietnam during the period from 2012 to 2018. The research model was developed with business efficiency as dependent variable and the relevant factors affecting the technology spillover capacity as independent variables. With a sample of 2,776 cross-sectional enterprises, panel data analysis approach was adopted to estimate the impact of technology spillover issue. Different spillover channels were also included in the analysis to enhance the empirical result. The study reveals that technology spillovers positively influence manufacturing business efficiency, in which horizontal spillover channel produces negative impact and vertical spillover channel, creates positive impact. Several factors that negatively affect the technology spillover capacity of businesses could be mentioned such as limited skills and experiences of workers, methods of implementing R&D, and the existence of FDI enterprises. Meanwhile, the rise of other factors related to joint-venture activities can help to increase the technology spillover capacity of businesses. In addition, skill and experience transfer makes a partial impact since this variable only positively affect the vertical spillover channel and provide no evidence of impact regarding horizontal spillover channel model.

2D ANALYTICAL MODEL OF THE FSW WELD ZONE AND FINITE ELEMENT HEAT TRANSFER ANALYSIS

  • S.R, Rajesh;Bang, Han-Sur;Kim, Heung-Ju;Bang, Hee-Seon
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2005년도 추계학술발표대회 개요집
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    • pp.135-137
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    • 2005
  • The body of the work covers FSW welding of Al6061 and its thermal distribution based on an analytical model for the heat input at the probe/matrix boundary of Al plates and FSW tool due to the effect of combined translation and rotational motion of the tool pin and shoulder. Finally the 2D- finite element heat transfer analysis program has been used to plot the heat distribution at the Friction Stir Welded joint in Al 6061 plate. The work concludes that the heat distribution result obtained from FE analysis has a reasonable agreement with the experimentally measured values.

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로봇 레이저용접을 위한 캐드캠 인터페이싱에 관한 연구 (Study on CAD/CAM Interfacing for Robot based Laser Welding)

  • 강희신;서정;김정오;박경택;조택동
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2007년 추계학술발표대회 개요집
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    • pp.67-69
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    • 2007
  • Laser welding technology for automobile body is studied. Laser system, robot and seam tracking system are used for 3D laser welding system. The laser system is used 4kW Nd:YAG laser(HL4006D) of Trumpf and the robot system is used IRB6400R of ABB. The seam tracking system is SMRT-20LS of ServoRobot. The welding joints of steel plate are butt and lap joint. The 3 dimensional laser welding for non-linear pipe welding line is performed.

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류마티스 관절염환자의 우울에 대한 사회적 지지기능 (Function of Social Support on Depression of Patients with Rheumatoid Arthritis)

  • 최순희
    • 근관절건강학회지
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    • 제3권1호
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    • pp.63-89
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    • 1996
  • This study has been done for the purpose of determining whether the positive association between social support and depression is attributable to an overall beneficial effect of support(direct effect) or to a process of support protecting persons from adverse effects of stressors such as life events, pain or physical disability (buffering effect). The sample consisted of 214 patients who were identified as the rheumatoid arthritis. The instruments used in this study were Depression Scale(CES-D), Perceived Social Support Scale, Life Events Questionnaire, AIMS Pain Scale, and Physical Disability Scale. The data were analysed by the use of t-test, ANOVA, Pearson Correlation Coefficient and Stepwise Multiple Regression. The results of this study are summerized as follows : 1. The 1st hypothesis, "The higher the life events degree, the higher the depression degree" was supported(r=.49, P=.0001). 2. The 2nd hypothesis, "The higher the pain degree, the higher the depression degree" was supported(r=.44, P=.0001). 3. The 3rd hypothesis, "The higher the physical disability degree, the higher the depression degree" was supported (r=.46, P=.0001). 4. The 4th hypothesis, "The higher the social support degree, the lower the depression degree" was supported(F=84.52, P=.0001). 5. The 5th hypothesis, "There will be different in the relationship between the degrees of life events and depression according to social support degree" was rejected (F=.29, P=.5928). 6. The 6th hypothesis, "There will be different in the relationship between the degrees of pain and depression according to social support degree" was supported (F=3.19, P=.0755). 7. The 7th hypothesis, "There will be different in the relationship between the degrees of physical disability and depression according to social support degree" was supported(F=5.69, P=.018). 8. The predictive variables for depression were the degrees for social support, life events, pain, and physical disability. 9. The depression degree showed a inverse correlation with social support degree (r=-.56, p=.0001). The social support degree showed a inverse correlation with the degrees of life events(r=-.22, p=.0007), pain(r=-.18, p=.0069) and physical disability(r=-.15, p=.0293). 10. The depression degree showed significant differences in the variables of sex (t=2.26, p=.025), educational level(r=.189, P=.006) and the number of treatment method (r=.201, P=.003). In conclusion, it was found that social support had the direct effect on depression and the buffering effect in each relationship between degrees of pain or physical disability and depression in patients with rheumatoid arthritis. So the researcher thinks that it is effective that nurses should provide these patients with social support to reduce depression in cases of having severe pain or physical disability.

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솔더 조인트 신뢰성 향상을 위한 무전해 니켈-도금의 표면형상 제어 (Study on Surface Morphology Control of Electroless Ni-P for Reliability Improvement of Solder Joints)

  • 이동준;최진원;조승현
    • 마이크로전자및패키징학회지
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    • 제15권3호
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    • pp.27-33
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    • 2008
  • PDA, 핸드폰과 같은 포터블 제품의 사용이 급증함에 따른 전자 제품의 사용 환경의 변화는 제품의 솔더 조인트 신뢰성을 더욱 필요로 하게 되었다. 무전해 니켈/금 도금 표면 처리는 솔더링 특성이 우수하고, 표면처리 두께가 균일하며 패키징 공정에서 사용되는 광학설비에서 인식이 잘되기 때문에 미세피치 SMT 디바이스와 BGA 기판에 폭넓게 사용되고 있다. 그러나 무전해 니켈/금 도금 표면과 솔더 계면에서 발생되는 취성 파괴가 문제점으로 지적되고 있다. 솔더의 취성 파괴는 솔더링시 금속간 화합물과 무전해 니켈층 사이에 형성된 P-rich 영역의 갈바닉 니켈 부식에 의한 black pad 현상에 기인한다. 이론적으로 평탄한 무전해 Ni표면은 무전해 금도금 과정 중 도금액의 균일하게 순환되기 때문에 black pad 발생을 억제하는 장점을 가지고 있다. 그러나 이러한 장점에도 불구하고 무전해 Ni층의 표면형상을 어떻게 제어 할지에 대한 연구는 충분히 이루어 지지 않고 있다. 본 연구에서는 Cu 하지층의 표면 형상이 무전해 Ni층의 표면 형상에 미치는 영향에 대하여 분석하였다. 이를 위해 Cu 에칭액과 Cu에칭 처리 횟수를 변화시켜 Cu 하지층의 표면 형상을 다양하게 변화시켰다.

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