• Title/Summary/Keyword: resistance management

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Cyclic testing of chevron braced steel frames with IPE shear panels

  • Zahrai, Seyed Mehdi
    • Steel and Composite Structures
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    • v.19 no.5
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    • pp.1167-1184
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    • 2015
  • Despite considerable life casualty and financial loss resulting from past earthquakes, many existing steel buildings are still seismically vulnerable as they have no lateral resistance or at least need some sort of retrofitting. Passive control methods with decreasing seismic demand and increasing ductility reduce rate of vulnerability of structures against earthquakes. One of the most effective and practical passive control methods is to use a shear panel system working as a ductile fuse in the structure. The shear Panel System, SPS, is located vertically between apex of two chevron braces and the flange of the floor beam. Seismic energy is highly dissipated through shear yielding of shear panel web while other elements of the structure remain almost elastic. In this paper, lateral behavior and related benefits of this system with narrow-flange link beams is experimentally investigated in chevron braced simple steel frames. For this purpose, five specimens with IPE (narrow-flange I section) shear panels were examined. All of the specimens showed high ductility and dissipated almost all input energy imposed to the structure. For example, maximum SPS shear distortion of 0.128-0.156 rad, overall ductility of 5.3-7.2, response modification factor of 7.1-11.2, and finally maximum equivalent viscous damping ratio of 35.5-40.2% in the last loading cycle corresponding to an average damping ratio of 26.7-30.6% were obtained. It was also shown that the beam, columns and braces remained elastic as expected. Considering this fact, by just changing the probably damaged shear panel pieces after earthquake, the structure can still be continuously used as another benefit of this proposed retrofitting system without the need to change the floor beam.

An Exploratory Research on Individual Differences of Technostress: In Convergence Age (융복합 시대에서 테크노 스트레스의 개인별 차이에 대한 연구)

  • Yim, Myung-Seong;Park, Min-Soo
    • Journal of Digital Convergence
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    • v.13 no.3
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    • pp.137-153
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    • 2015
  • Technostress- a term coined by Craig Brod- refers to a modern disease of adaptation caused by an inability to cope with new technologies. Stress is a person's adaptive response to a stimulus that places excessive psychological or physical demands on that person. In a similar vein, technostress can affect a variety of side effect such as low work productivity and resistance against new technology. The purpose of this study is thus to investigate of differences of technostressors using demographic informations such as gender, age, computer use skill, and industrial types. To do this, we conducted independence t-test and analysis of variance. We found that demographic characteristics can affect the differences of technostressors. Conclusions and implications are discussed in the last section of this paper.

Users' Attitudes for the Trail Structures in Hallasan National Park, Korea - In the Case Study of Eorimok - (한라산국립공원 탐방로 보행시설에 대한 탐방객 태도 - 어리목 구간을 중심으로 -)

  • Yoo, Ki-Joon;Kwon, Tae-Ho;Cho, Keun-Sik;Cho, Woo
    • Korean Journal of Environment and Ecology
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    • v.21 no.2
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    • pp.168-175
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    • 2007
  • For maximum utility of trails, there is a need for better knowledge of characteristics of trail use and its users. The purpose of this study is to find out users' attitudes toward trail structures in Eorimok exploring route in Hallasan National Park managerial purposes. A questionnaire survey was conducted to 138 people on the way back home from their visit to the site from July to August, 2007. The geological conditions of 7 types of pedestrian trail structures were rated relatively high both in quantity and quality. The responses were noticeably positive about the natural materials used in wood deck and PP rope railings from the point of three aspects: harmony with nature, visitor convenience and resources conservation. It seems necessary to replace steel structures with native materials because such unnatural materials used in a natural setting are subject to visitor's resistance.

An 8-wk, randomized, double-blind, placebo-controlled clinical trial for the antidiabetic effects of hydrolyzed ginseng extract

  • Park, Soo-Hyun;Oh, Mi-Ra;Choi, Eun-Kyung;Kim, Min-Gul;Ha, Ki-Chan;Lee, Seung-Kwon;Kim, Young-Gon;Park, Byung-Hyun;Kim, Dal-Sik;Chae, Soo-Wan
    • Journal of Ginseng Research
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    • v.38 no.4
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    • pp.239-243
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    • 2014
  • Background: To investigate the antidiabetic effects of hydrolyzed ginseng extract (HGE) for Korean participants in an 8-wk, randomized, double-blinded, placebo-controlled clinical trial. Methods: Impaired fasting glucose participants [fasting plasma glucose (FPG) ${\geq}5.6mM$ or < 6.9mM who had not been diagnosed with any disease and met the inclusion criteria were recruited for this study. The 23 participants were randomly divided into either the HGE (n = 12, 960 mg/d) or placebo (n = 11) group. Outcomes included measurements of efficacy (FPG, postprandial glucose, fasting plasma insulin, postprandial insulin, homeostatic model assessment-insulin resistance, and homeostatic model assessment-${\beta}$) and safety (adverse events, laboratory tests, electrocardiogram, and vital signs). Results: After 8 wk of HGE supplementation, FPG and postprandial glucose were significantly decreased in the HGE group compared to the placebo group. No clinically significant changes in any safety parameter were observed. Our study revealed that HGE is a potent antidiabetic agent that does not produce noticeable adverse effects. Conclusion: HGE supplementation may be effective for treating impaired fasting glucose individuals.

Case Studies for Anlayzing Effects of Outriggers on Gravity Load Managements (아웃리거의 중력하중 조절 효과 분석을 위한 사례연구)

  • Kang, Su-Min;Eom, Tae-Sung;Kim, Jae-Yo
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.23 no.3
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    • pp.255-266
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    • 2010
  • In high-rise buildings, an outrigger system is frequently used as a resisting system for lateral loads. Since the outriggers tie exterior columns and an interior core, exterior columns can participate in the lateral load resisting system and the structural resistance capacity can be increased. However, the outriggers contribute for controlling gravity loads as well as lateral loads. The flows of gravity loads can be changed by the members of outriggers, for the purposes of transferring loads to mega-columns, distributing gravity loads equally among vertical members of columns, walls, or piles, minimizing differential settlements in a foundation system, and so on. In this study, by computational structural analyses of high-rise buildings over 100 floors, the effects of outriggers on controlling gravity loads are analyzed. Analyses for 3-dimensional models with or without outrigger members are performed, and then the gravity load distributions in columns and piles and foundation settlements are analyzed. Also, the effects of outriggers on gravity load controls during construction stages as well as after construction are included.

Studies on the pathogenic Escherichia coli isolated from piglets with diarrhea in Chonnam (전남 지방의 설사 자돈에서 분리된 병원성 대장균에 관한 연구)

  • 김자숙;박영춘;정인호;오은희;박석준;고홍범
    • Korean Journal of Veterinary Service
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    • v.19 no.2
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    • pp.139-153
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    • 1996
  • Porcine E coli infection is a disease caused by Enterotoxin produced by Enterotoxigenic Escherichia coli(ETEC). Enteric colibacillosis has become an economically important disease in pigs as a result of increasing intensification of farrowing management. The present study undertaken to obtain the antibiotic sensitivity and distribution of serogroups and pili producibility test of ETEC from E. coli isolates in Chonnam. The results obtained were as follows. 1. A total of 71 isolates identified as E, coli employing IMViC system from rectal specimens of 54 piglets with diarrhea. 2. In antibiotic sensitivity test, isolates showed high sensitivity to AN, CM, Fox, GM, but resistance to EM, NA TC. 3. The distribution of 25 Isolates of serogroups were 0141:K85(11.3%), 08:K87(8.5%), 064:K (5.6%), 0138:K8l (4.2%), 0139 :K82(2.8%), 0157:K88ac(1.4%) and 0149:K9l (1.4%). 4. MRHA of guinea pig erythrocytes was detected in 8 out of 25OK serotypes and 9 out of 46 unidentified serotypes. MRHA titers of serotypes showed from 64 to 128 in 0141: K85, 2 in 0138:K8l and no titers in 0139:K82. 5. The production of heat labile enterotoxin of ETEC was detect 39 out of 52 isolates showed $\beta$-hemolysin, 7 out of 52 isolates showed ${\gamma}$-hemolysin and 6 out of 52 isolates showed ${\gamma}$-hemolysin by $GM_1$ganglioside ELISA. The distribution of LT toxin were in 12 isolate showed $\beta$-hemolysin, 2 isolates showed ${\alpha}$-hemolysin and 3 isolates showed ${\gamma}$-hemolysin in 25 OK serotypes.

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Genetic Analysis and Characterization of a Bacteriophage ØCJ19 Active against Enterotoxigenic Escherichia coli

  • Kim, Gyeong-Hwuii;Kim, Jae-Won;Kim, Jaegon;Chae, Jong Pyo;Lee, Jin-Sun;Yoon, Sung-Sik
    • Food Science of Animal Resources
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    • v.40 no.5
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    • pp.746-757
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    • 2020
  • Enterotoxigenic Escherichia coli (ETEC) is the major pathogenic E. coli that causes diarrhea and edema in post-weaning piglets. In this study, we describe the morphology and characteristics of ØCJ19, a bacteriophage that infects ETEC, and performed genetic analysis. Phage ØCJ19 belongs to the family Myoviridae. One-step growth curve showed a latent phase of 5 min and burst size of approximately 20 phage particles/infected cell. Phage infectivity was stable for 2 h between 4℃ and 55℃, and the phage was stable between pH 3 and 11. Genetic analysis revealed that phage ØCJ19 has a total of 49,567 bases and 79 open reading frames (ORFs). The full genomic sequence of phage ØCJ19 showed the most similarity to an Escherichia phage, vB_EcoS_ESCO41. There were no genes encoding lysogeny, toxins, virulence factors, or antibiotic resistance in this phage, suggesting that this phage can be used safely as a biological agent to control ETEC. Comparative genomic analysis in terms of the tail fiber proteins could provide genetic insight into host recognition and the relationship with other coliphages. These results showed the possibility to improve food safety by applying phage ØCJ19 to foods of animal origin contaminated with ETEC and suggests that it could be the basis for establishing a safety management system in the animal husbandry.

Development of a Low-Power Standalone Heat Detector Using a Critical-Temperature Switch (임계온도스위치를 이용한 저전력 단독경보형 정온식 감지기 개발)

  • Jo, Sungwoo;Jung, Sun-Kyu;Son, Jimin;Kim, Hyun-Tak
    • Fire Science and Engineering
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    • v.33 no.4
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    • pp.70-76
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    • 2019
  • This paper reports development of a low-power standalone heat detector using a Critical-Temperature Switch. The Critical-Temperature Switch, which is a thermally sensitive and passive component whose resistance decreases significantly at 70 ℃ due to a metal-insulator transition, provides reliable temperature measurements. This digital-like behavior of the Critical-Temperature Switch can detect fires without a microcontroller, meaning that it can minimize the power consumption of the standalone heat detector. The experimental results showed that the standalone heat detector using the Critical-Temperature Switch complied with the Notification of the National Emergency Management Agency. Compared to conventional standalone heat detectors, only 70% of the power was consumed monitoring the fires.

A Study on Color Meditation Programs for Wounded Heart Healing of University Students (대학생의 마음상처 치유를 위한 색채명상 프로그램 개발연구)

  • Ha, Tai-Hyun;Baek, Hyeon-Gi
    • Journal of Digital Convergence
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    • v.12 no.5
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    • pp.467-477
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    • 2014
  • The goal of this study is to explore 'color meditation programs' for wounded heart healing of University students. Color meditation was found to alleviate negative psychological symptoms of young people and to raise their quality of life. Furthermore this survey was investigated in a way that participants who are not familiar with meditation activities could access this program without resistance. Also the characteristic points of this program are to be properly reconstructed and supplemented so that it can be applied without any limitations in schools. The satisfaction with color meditation program rather than the motivation of participation in it was determined to affect mental health. These results suggest that simply participating in color meditation program does not mean influencing mental health. Understanding and being satisfied with color meditation was found to be the key to mental health.

A Scheme for User Authentication using Pupil (눈동자를 이용한 사용자 인증기법)

  • Lee, Jae-Wook;Kang, Bo-Seon;Lee, Keun-Ho
    • Journal of Digital Convergence
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    • v.14 no.9
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    • pp.325-329
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    • 2016
  • Facial authentication has the limelight because it has less resistance and it is hard to falsify among various biometric identification. The algorithm of facial authentication can bring about huge difference in accuracy and speed by the algorithm construction. Along with face-extracted data by tracing and extracting pupil, the thesis studied algorithm which extracts data to improve error rate and to accurately authenticate face. It detects face by cascade, selects as significant area, divides the facial area into 4 equal parts to save the coordinate of object. Also, to detect pupil from the eye, the binarization is conducted and it detects pupil by Hough conversion. The core coordinate of detected pupil is saved and calculated to conduct facial authentication through data matching. The thesis studied optimized facial authentication algorithm which accurately calculates facial data with pupil trace.