• Title/Summary/Keyword: Reinforcement theory

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Redistribution of Negative Moments in Beams Subjected to Lateral Load (횡하중에 대한 휨재의 부모멘트 재분배)

  • Eom, Tae-Sung
    • Journal of the Korea Concrete Institute
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    • v.23 no.6
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    • pp.731-740
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    • 2011
  • Provisions for the redistribution of negative moments in KCI 2007 and ACI 318-08 use a method for continuous flexural members subjected to uniformly-distributed gravity load. Moment redistributions and plastic rotations in beams of reinforced concrete moment frames subjected to lateral load differ from those in continuous flexural members due to gravity load. In the present study, a quantitative relationship between the moment redistribution and plastic rotation is established for beams subjected to both lateral and gravity loads. Based on the relationship, a design method for the redistribution of negative moments is proposed based on a plastic rotation capacity. The percentage change in negative moments in the beam was defined as a function of the tensile strain of re-bars at the section of maximum negative moment, which is determined by a section analysis at an ultimate state using KCI 2007 and ACI 318-08. Span, reinforcement ratio, cracked section stiffness, and strain-hardening behavior substantially affected the moment redistribution. Design guidelines and examples for the redistribution of the factored negative moments determined by elastic theory for beams under lateral load are presented.

A Study on the educational direction of Dental Technology Department in the 21st century (21C 치과 기공과 교육의 방향에 대한 연구)

  • Park, J.H.
    • Journal of Technologic Dentistry
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    • v.21 no.1
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    • pp.153-163
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    • 1999
  • The 21st centurt, the era of change-space, is requesting us to readjust our education system. In other words, we should renew it by looking back into the past cultivate more advanced ideas. As a matter of fact junior colleges have been considered just as miniture of universities in every way such as curriculum, prossor emploment, school affairs, etc. Therefore we should change our existing education system not to be criticized for the next century. May students are trained for industry as dental technicians in our department of college. We should educate experiment and practice substantially as college professors as well as exert ourselves in developing our abilities to adapt to high diverse industrial technique, putting emphasis on practice more than theory. It is mecessary for us to sufficiently teach the technique to good students and make them display their abilities in order to produce high quality goods. Reinvestment ineducation is a condition precedent. Dental laboratories have just employed the students that graduated from our college. However it's time for a change. They should pay attention to our education and assist us in all respects with the thought of equally educating professional dental technicians together with us. The field practice system is subject to reinforcement so that our students have more opporunities of utilizing the tools and materials for practice. Finally we should not only carry out new reserch more deeply no less than dental technicians who are experienced in business for development of education system but endeavor to meet pratical education by adding what is pratically needed in dental laboratories to the existing education system.

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Out-of-Plane Shear Strength Models of SC Wall (SC 벽체의 면외 전단강도 특성)

  • Hon, Sung-Gul;Lee, Kyuong-Jin;Park, Dong-Soo;Kim, Won-Ki;Lee, Dong-Hun
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.04a
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    • pp.225-228
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    • 2008
  • This paper presents out-of-plane shear strength models for composite wall with steel plates based on limit theorem in the framework of the plasticity theory. The formulas proposed by JEAG 4618 need to be reconsidered with a couple of limitations; ignoring the effect of bond stress generated by studs in the process of calculating arch action, illogically discriminating between concrete shear cracking strength and arch strength by algebraic relation in short shear span ratio(0-2.0). In most cases, reinforcement ratio is not sufficient to yield, as a result, arch strength is determined by accounting equilibrium including both bond strength and concrete compressive strength. We conducted experimental research assuming that SC wall is a continuous beam under the simplified loading patterns, changing main valuables involving the number of studs, stirrups. The results show good agreements with the formula and we quoted the test results of JEAG.

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Nonlinear Finite Element Analysis for RC Shear Wall with an Opening Considering Rebar Development Length (철근 정착길이를 고려한 개구부가 있는 철근콘크리트 전단벽의 유한요소해석)

  • Choi, Yun-Bum;Lee, Seong-Cheol
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.29 no.6
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    • pp.547-554
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    • 2016
  • In this study, nonlinear finite element analysis based on the Modified Compression Field Theory has been conducted to evaluate shear strength of RC walls with opening. On the analysis, reinforcement ratio within development length of rebars nearby the opening was reduced in the model in order to investigate the effect of opening on shear strength of RC shear walls. The nonlinear finite element analysis has been verified through comparison with the test result in literature. Through the verification, it was investigated that the analysis considering the development length of rebars well reflected the effect of an opening on shear strength of RC shear walls while current design provisions did not reasonably consider one.

Mechanical buckling of FG-CNTs reinforced composite plate with parabolic distribution using Hamilton's energy principle

  • Tayeb, Tayeb Si;Zidour, Mohamed;Bensattalah, Tayeb;Heireche, Houari;Benahmed, Abdelillah;Bedia, E.A. Adda
    • Advances in nano research
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    • v.8 no.2
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    • pp.135-148
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    • 2020
  • The incorporation of carbon nanotubes in a polymer matrix makes it possible to obtain nanocomposite materials with exceptional properties. It's in this scientific background that this work was based. There are several theories that deal with the behavior of plates, in this research based on the Mindlin-Reissner theory that takes into account the transversal shear effect, for analysis of the critical buckling load of a reinforced polymer plate with parabolic distribution of carbon nanotubes. The equations of the model are derived and the critical loads of linear and parabolic distribution of carbon nanotubes are obtained. With different disposition of nanotubes of carbon in the polymer matrix, the effects of different parameters such as the volume fractions, the plate geometric ratios and the number of modes on the critical load buckling are analysed and discussed. The results show that the critical buckling load of parabolic distribution is larger than the linear distribution. This variation is attributed to the concentration of reinforcement (CNTs) at the top and bottom faces for the X-CNT type which make the plate more rigid against buckling.

A Study on Acupoint SP3 in Saam Acupuncture Method (사암도인침법에서 태백혈의 운용에 대한 연구)

  • Kim, Song-Yi;Lee, Soon-Ho;Park, Ji-Yeun;Park, Hi-Joon
    • Korean Journal of Acupuncture
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    • v.31 no.4
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    • pp.179-187
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    • 2014
  • Objectives : Saam acupuncture initiated by Saamdoin is traditional and originative method, which is characterized by applying the five phases theory and mother-child reinforcement-reduction principle to the selection of acupoints and needling manipulation. Our study was aimed to summarize and assess the use of acupoint SP3(Taebaek) in Saam acupuncture treatment and to further understand Saam acupuncture in an aspect of the combination of acupoints. Methods : We searched the data based on "(Do Hae Kyo Kam) Sa-Ahm's acupuncture method" for SP3 used and acupoint combination including SP3. We performed frequency analysis, network analysis, and cluster analysis for quantitative aspect. To understand clinical implication of SP3 with another acupoint, qualitative and descriptive methods were also carried out. Results and Conclusions : In our study, SP3 was frequently used for tonification of lung, spleen, heart, and kidney meridian and sedation of kidney, heart, and lung meridian. For this, many acupoints such as LU8, LU9, KI3, HT8, KI7, LU10 and LR1 were used with SP3. The combination of SP3 and other acupoints were used to treat stroke, common cold, and pain conditions including headache, low back pain, respiratory disease as well as gastroenteric troubles including stomachache, indigestion, vomiting, and constipation. To further understand Saam acupuncture, an understanding of the five transport points based on five elements characters, pathological changes (deficiency and excess) of viscera and bowels, and concept of source point should be preceded.

Evaluation of Load Capacity Reduction in RC Beam with Corroded FRP Hybrid Bar and Steel (철근부식을 고려한 FRP Hybrid Bar 및 일반 철근을 가진 RC 보의 내력저하 평가)

  • Oh, Kyung-Suk;Moon, Jin-Man;Park, Ki-Tae;Kwon, Seung-Jun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.20 no.2
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    • pp.10-17
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    • 2016
  • Steel corrosion is a very significant problem both to durability and structural safety since reinforcement has to support loads in tensile region in RC(Reinforced Concrete) member. In the paper, newly invented FRP Hybrid Bar and normal steel are embedded in RC beam member, and ICM (Impressed Current Method) is adopted for corrosion acceleration. Utilizing the previous theory of Faraday's Law, corrosion amount is calculated and flexural tests are performed for RC beam with FRP Hybrid Bar and steel, respectively. Corrosion amount level of 4.9~7.8% is measured in normal RC member and the related reduction of flexural capacity is measured to be -25.4~-50.8%, however there are no significant reduction of flexural capacity and corrosion initiation in RC samples with FRP Hybrid Bar due to high resistance of epoxy-coated steel to corrosion initiation. In the accelerated corrosion test, excellent performance of anti-corrosion and bonding with concrete are evaluated but durability evaluation through long-term submerged test is required for actual utilization.

The Distinctive Feature of Acupuncture Treatment in ZhangJinYoPian(藏珍要編) (19세기 조선 침구서 장진요편의 침법 연구)

  • Oh, Jun-Ho
    • Korean Journal of Acupuncture
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    • v.27 no.1
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    • pp.159-168
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    • 2010
  • Objective: ZhangJinYoPian(藏珍要編, ZJYP) is a book witten by Song-WooGe in the late 19th century. While Korea has lost this book to tell us Korea traditional acupuncture treatment in the late 19th century, This book appeared as a manuscript in Japan. There is no reaserch or study carried out for this book. Furthermore, a few people know existence of this book. So I analyzed acupuncture treatment of the ZJYP and sort out the distinctive feature of it. Method: For that, I studied bibliographic information of this book and classified contents of it into three parts - medical thought, needle manipulation and acupoint selection to consider it's caracteristics. Results and Conclusions: 1. The author of ZJYP thought that weakness of good power in the body and strongness of evil power out of the body cause a disease. so Doctor should examine quality of both to care patient's pain. 2. The author of ZJYP thought that needle manipulation is one of the most important thing. Doctors can use needle manipulation to control patient condition. Especially, he suggested cooling and heating manipulation except reinforcement and reduction. 3. He stressed viscera and bowels. he located viscera and bowels theory in front of the book to explain relationship of these. It shows us that ZJYP maintained academic characteristics of acupuncture in Chosun-Korea. 4. While He minimized the number of acupoints used in treatment, he multiplied its combination. He selected one or two acupoints from each meridian pathway. It include Eight Confluent points(八脈交會穴). But these points were used in different ways to control the viscera and bowels, not to care the eight extra meridians.

Regional Art and Power (지역 미술과 권력)

  • Park, Young-Taik
    • The Journal of Art Theory & Practice
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    • no.3
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    • pp.35-50
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    • 2005
  • For us, any regional art exist? Almost all art events today take place mostly in Seoul. Concentrating on the reinforcement of its power, the regional art world remains isolated without any connection with the Seoul art community. It is completely closed off from the central art scene. The regional art world seems to consider that more helpful in consolidating its status. It is in real sense suffering the absence of art criticism and art media, lack of an understanding of art and backwardness of art education. Many regional artists are dreaming of moving out from their domain, aspiring to be a member of the central art world. They make an effort to assimilate into a refined, modern style of the central art circle, rather than striving to create works imbued with regionality and locality. As the artists living in the provinces, the characteristics of their district should be above all else reflected in their art. Although they are less informed about the latest trend of culture and art, their art has to be something passionately and obstinately embodying the intrinsic quality of their regions. They have to find a practical solution more positively, instead of merely complaining about the poor condition of the regional art community. There is the need to bring about a turnabout in our awareness that regional art is confined to any limit and cannot be in the center of the entire art world. What' s most significant is to dissolve factionalism and not to depend on school ties or regional networks. As a reaction against authoritarianism, regional art has to put emphasis on attaining its originality. For this, regional art should respect regional tradition, history and background and break away from an old convention of wielding power.

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The Organization Performance Reinforcement by a Utilization Level of the Smart Work (스마트워크 활용 수준에 따른 조직성과 강화에 관한 연구)

  • Jung, Byoungho
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.14 no.4
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    • pp.189-204
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    • 2018
  • The purpose of this study is to examine an organizational performance difference by individual utilization level of the smart work. The Smart work help minimizing business process and improving organization productivity based on information technology. This new technology provides a flexible way of the task through smart-work center, videoconferencing, telecommuting, mobile(remote control) and business-only messenger. This investment changes organizational culture, institutions and behavior by new technology applying. The organization system change due to smart work has trouble between alteration preferences and existing maintains a group. In response, the organization should make investment justification of smart work for institutional and culture stabilized by a new system in organization. I set up the analytical process of four stages for empirical research. It will analyze an operation difference of the smart work between pre and post investment in the first-step analysis. The two-step analysis will conduct a text mining analysis of smart work operations. The three-step analysis will identify organization performance differences among individual levels in smart work. The four-step analysis will identify a factor difference in organizational performance by individual utilization level on smart work. According to the study, It has been revealed a difference between the pre and post investment performance on smart work. The text mining analyses many appeared an improvement opinion of organizational culture. Next, there is a difference in organization performance among utilize groups of smart work. Furthermore, the factors of organizational performance among groups appeared differently. The theoretical contribution of this study provided to expand the organizational theory of organization change and resistance. The practical implications provided to require a strong guideline an organizational culture and institution for smart work.