• Structural Engineering and Mechanics
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• 제51권1호
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• pp.131-140
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• 2014

This study focuses on seismic behaviour of tall piers characterized by high slender ratio. Two analysis models were developed based on elastic-plastic hinged beam element and elastic-plastic fiber beam element, respectively. The effect of the division density of elastic-plastic hinged beam element on seismic demand was discussed firstly to seek a rational analysis model for tall piers. Then structural seismic behaviour such as the formation of plastic hinges, the development of plastic zone, and the displacement at the top of the tall piers were investigated through incremental dynamic analysis. It showed that the seismic behaviour of a tall pier was quite different from that of a lower pier due to higher modes contributions. In a tall pier, an additional plastic zone may occur at the middle height of the pier with the increase of seismic excitation. Moreover, the maximum curvature reaction at the bottom section and maximum lateral displacement at the top turned out to be seriously out of phase for a tall pier due to the higher modes effect, and thus pushover analysis can not appropriately predict the local displacement capacity.

• Steel and Composite Structures
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• 제13권4호
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• pp.343-365
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• 2012

Steel suspension members subjected to tension and bending offer an economical and efficient alternative for many structural problems. This paper is concerned with the elastic and elastic-plastic behaviour of suspension members with bending stiffness subjected to vertical point and uniformly distributed loads. An experimental study is described which focuses on the response of three suspension members with various T-shaped steel hot rolled sections and geometric configurations. The tests enable direct assessment of the influence of a key parameter such as the sag-to-span ratio on the response of suspension members. Detailed nonlinear finite-element models are generated to provide a tool for theoretical analyses and to facilitate further understanding of the behaviour. Results demonstrate that experimentally obtained responses can generally be closely predicted numerically because there are relatively good agreements between finite element and tests results. The results and observations of subsequent numerical parametric studies offer an insight into the key factors that govern the behaviour of suspension members with bending stiffness in the elastic-plastic range.

• 한국공간구조학회논문집
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• 제14권3호
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• pp.93-100
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• 2014

Ethylene Tetrafluoroethylene (ETFE) has been widely used in long-span buildings because of its light weight and high transparency. This paper studies the short and long term creep behaviour of ETFE foil. A series of short-term creep and recovery tests were performed, in which the residual strain was observed. A long-term creep test of the ETFE foil was also performed over 110 days. A viscoelastic-plastic model was then established to describe the short-term creep and recovery behaviour. The model contains a traditional multi-Kelvin part and an added steady-flow component to represent the viscoelastic and viscoplastic behaviour, respectively. The model successfully fit the data for three stresses and six temperatures. Additionally, time-temperature equivalency was adopted to predict the long-term creep behaviour of ETFE foil. Horizontal shifting factors were determined from the process of shifting creep-curves at six temperatures. The long-term creep behaviours at three temperatures were predicted. Finally, the long-term creep test showed that the short-term creep test at identical temperatures insufficiently predicted additional creep behaviour, and the long-term test verified the horizontal shifting factors derived from the time-temperature equivalency.

• Asian-Australasian Journal of Animal Sciences
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• 제14권2호
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• pp.184-188
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• 2001

In a summer study during May to July, involving 12 young Murrah buffalo bulls at forty months of average age, the effects of multiple shower vs single shower body cooling and vitamin A, D and E supplementation on the sexual behaviour, semen quality and freezability were investigated. The animals were divided into two groups (6 animals in each group) and housed in a half-walled shed with proper spacing, the feeding management being identical. The bulls in the control group were given a single shower at 1000 h, whereas the experimental bulls were given four showers at 10,12,14 and 16 h. In addition, the experimental bulls were given vitamin A, D and E injections at fifteen day intervals. The sexual behaviour of bulls was observed in terms of reaction time, sexual aggressiveness and ejaculatory thrust. Semen quality of all the bulls was assessed in terms of volume, mass activity, live-dead sperm and sperm concentration, sperm motility and morphology, and acrosomal abnormality. The sexual behaviour did not vary significantly between the groups, whereas semen quality differed significantly for volume, per cent live sperms, total sperms per ejaculate and total live sperm per ejaculate between groups. It can be concluded that sexual behaviour was not influenced by the thermal comfort treatment coupled with periodic vitamin A, D and E injections. But the treatments improved most of the seminal traits in the experimental group of bulls. However, benefit of treatment was not reflected in the freezability traits of the semen.

• 터널과지하공간
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• 제17권1호
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• pp.9-16
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• 2007

굴진장이 터널의 안정성 및 시공비에 미치는 영향에 대해서는 많은 연구자와 기술자들이 잘 알고 있지만, 아직 굴진장 결정에 대해서 일관된 절차가 수립되지는 못한 실정이다. 본 연구에서는 굴진장을 고려한 연암터널의 막장과 무지보 구간의 거동형태를 실내모형실험, PFC3D 및 FDM 해석을 통하여 조사하였다. 총 다섯 개의 거동형태를 정의하였고, 막장 안전율과 설계 도표를 통해 거동형태를 정량적으로 판단할 수 있도록 하였다. 비록 본 연구에서 제안한 방법이 몇몇 제한을 갖지만, 굴진장과 굴착의 최적화를 위한 유용한 정보를 제공할 수 있을 것으로 사료된다.

• 한국축산시설환경학회지
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• 제6권2호
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• pp.97-104
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• 2000

This study was carried out to determine the effects of different weaning age on feeding performance and behaviour of piglets. Sixty crossbred(YLxD) litters of piglets were randomly alloted to be 15 pens with 4 piglets per pen and 5 pens per treatment by weaned at 14, 21, and 28 days. Pens were video-taped for 24 hours immediately at 7 weeks and 8 weeks of age. The piglets weaned at 14 and 21 days were significantly (P<0.05) much intake than piglets weaning at 28 days. The piglets weaning at 14 days were significantly lighter than piglets weaning at 14 and 21 days fro m2 weeks to 8 weeks age. However, feed conversion ration was significantly(P<0.05) improved according to late weaning days. Times spent engaged in Feeding, lying and walking were similar in piglets across weaning age. They also showed similar occurrence of drinking and agonistic behaviour at 7 weeks and 8 weeks of age. Piglets weaned at 14 days exhibited more belly-nosing behaviour at 7 weeks of age, but similar in piglets at 8 weeks of age across weaning age. We concluded that piglets performance influenced by weaning day, however time spent for feeding, lying and walking behaviour were no significance. Drinking, Agonistic and belly-nosing were not significantly different by weaning age.

• Steel and Composite Structures
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• 제37권5호
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• pp.517-532
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• 2020

This paper firstly developed a new type of Double Skin Composite (DSC) beams using novel enhanced C-channels (ECs). The shear behaviour of novel ECs was firstly studied through two push-out tests. Eleven full-scale DSC beams with ECs (DSCB-ECs) were tested under four-point loading to study their ultimate strength behaviours, and the studied parameters were thickness of steel faceplate, spacing of ECs, shear span, and strength of concrete core. Test results showed that all the DSCB-ECs failed in flexure-governed mode, which confirmed the effective bonding of ECs. The working mechanisms of DSCB-ECs with different parameters were reported, analysed and discussed. The load-deflection (or strain) behaviour of DSCB-ECs were also detailed reported. The effects of studied parameters on ultimate strength behaviour of DSCB-ECs have been discussed and analysed. Including the experimental studies, this paper also developed theoretical models to predict the initial stiffness, elastic stiffness, cracking, yielding, and ultimate loads of DSCB-ECs. Validations of predictions against 11 test results proved the reasonable estimations of the developed theoretical models on those stiffness and strength indexes. Finally, conclusions were given based on these tests and analysis.

• 한국축산시설환경학회지
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• 제5권1호
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• pp.29-36
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• 1999

This study was conducted to determine the effects of dietary swine manure and food waste on feeding and drinking behaviours in broiler chicks. A total of 240 birds with 40g of initial weight were randomly assigned in the 8$\times$3 randomized complete block design and 10 birds per replicate. Extrusion recycled feeds(ERF) were prepared by extruding a mixture of 40% swine manure+40% food waste(FW)+20% corn. The birds assigned to one of the 8 dietary regimens; 0, 10, 30, 40% ERF of 20, 40, 60% FW in the place of a commercial boiler starter diet. Video recording were made after one week of adaptation period to the regimen. The tapes were played in a slow motion to examine feeding and drinking behaviour. Feeding and drinking times were greater in the day time at the night. Feeding times peaked at 4 hour intervals. Drinking time increased about 2 times on FW feeding compared to the other treatment groups. The results indicated that feeding and drinking behaviour could be influenced by the dietary regimens and that FW feeding increased drinking. The data also suggested that the FW could replace within 40% of broiler starter diet.

• Steel and Composite Structures
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• 제5권6호
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• pp.485-513
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• 2005

This paper presents a state-of-the-art on the behaviour of steel joints under fire loading and some recent developments in this field, currently being carried out by the authors. Firstly, a review of the experimental research work on steel joints is presented, subdivided into isolated member tests, sub-structure tests and tests on complete building structures. Special emphasis is placed on the seventh Cardington test, carried out by the authors within a collaborative research project led by the Czech Technical University in Prague. Secondly, a brief review of various temperature distributions within a joint is presented, followed by a discussion of the behaviour of isolated joints at elevated temperature, focussing on failure modes and analytical procedures for predicting the moment-rotation behaviour of joints at elevated temperature. Finally, a description of the coupled behaviour of joints as part of complete structures is presented, describing previous work and investigations on real fire (including heating and cooling phases) currently being carried out by the authors.

• 벤처창업연구
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• 제8권3호
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• pp.179-187
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• 2013

과거에는 품질의 좋고 나쁨의 기준이 정해진 특정 규정(기준)의 충족 여부였지만 최근엔 소비자(고객)의 만족 여부가 해당 제품의 질을 평가하는 기준이 되고 있다. 이는 서비스업의 경우에도 마찬가지이다. 본 연구에서는 의료산업에서의 서비스 품질과 서비스 가치가 고객행동과 어떤 관련성이 있는지와 서비스 관계품질이 서비스품질 및 가치와 고객행동에 어떤 매개역할을 하는지에 대해 실증 연구한 것이다. 컴퓨터 SPSS 패키지에 의해 조사 분석한 결과 의료산업 서비스품질 및 서비스가치는 고객행동과 양의 관련이 있는 것으로 나타났고, 서비스관계품질이 서비스품질 및 가치와 고객행동 간에 매개역할을 하고 있는 것으로 나타났다.