• Computers and Concrete
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• 제9권6호
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• pp.403-426
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• 2012

This paper deals with the structural behaviour of tapered concrete-filled steel composite (TCFSC) columns under eccentric loading. Finite element software LUSAS is used to perform the nonlinear analyses to predict the structural behaviour of the columns. Results from the finite element modelling and existing experimental test are compared to verify the accuracy of the modelling. It is demonstrated that they correlate reasonably well with each other; therefore, the proposed finite element modelling is absolutely accurate to predict the structural behaviour of the columns. Nonlinear analyses are carried out to investigate the behaviour of the columns where the main parameters are: (1) tapered angle (from $0^{\circ}$ to $2.75^{\circ}$); (2) steel wall thickness (from 3 mm to 4 mm); (3) load eccentricity (15 mm and 30 mm); (4) L/H ratio (from 10.67 to 17.33); (5) concrete compressive strength (from 30 MPa to 60 MPa); (6) steel yield stress (from 250 MPa to 495 MPa). Results are depicted in the form of load versus mid-height deflection plots. Effects of various tapered angles, steel wall thicknesses, and L/H ratios on the ultimate load capacity, ductility and stiffness of the columns are studied. Effects of different load eccentricities, concrete compressive strengths and steel yield stresses on the ultimate load capacity of the columns are also examined. It is concluded from the study that the parameters considerably influence the structural behaviour of the columns.

• Asian-Australasian Journal of Animal Sciences
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• 제26권10호
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• pp.1496-1503
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• 2013

The objective of this study was to determine the effect of municipal abattoir conditions and animal factors on avoidance-related behaviour (AB) of sheep at slaughter, bleeding times (BT) and mutton quality. The behaviour of 66 castrates and 19 ewes of different age categories was observed at three stages of slaughter. Higher behaviour scores indicated higher levels of AB. Time intervals between the start of blood flow and the time the flow changed from a constant stream into drips were recorded as BT. Thirty two meat samples were obtained to measure quality variables. These were colour ($L^*$, $a^*$ and $b^*$), $pH_{24}$, temperature, cooking loss (CL) and tenderness. Correlations were determined between BT and meat quality variables. Animal behaviour at slaughter differed with breed, gender and age group. Avoidance behaviour was higher in the Dorper breed than in both the Merino breed and their crosses. It was also higher in younger (<10 months) lambs than in older sheep. Castrates were more aggressive or in panic than ewes. Castrates had longer ($72.6{\pm}0.53s$) BT than the ewes ($63.6{\pm}2.82s$). Ewes had higher CL ($39.8{\pm}1.04%$) values than castrates ($35.1{\pm}0.95%$). Meat from castrates was tougher ($32.6{\pm}1.95N$) than the meat from ewes ($24.3{\pm}1.16N$). There were no significant correlations obtained between BT and meat quality variables. It can therefore be concluded that abattoir conditions, breed, age and gender had an effect on AB at slaughter. Gender had an effect on BT and mutton quality.

• Structural Engineering and Mechanics
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• 제21권6호
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• pp.659-676
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• 2005

The novel form of composite walling system consists of two skins of profiled steel sheeting with an in-fill of concrete. The behaviour of such walling under in-plane shear is important in order to utilise this system as shear elements in a steel framed building. Steel sheet-concrete interface governs composite action, overall behaviour and failure modes of such walls. This paper describes the finite element (FE) modelling of the shear behaviour of walls with particular emphasis on the simulation of steel-concrete interface. The modelling of complex non-linear steel-concrete interaction in composite walls is conducted by using different FE models. Four FE models are developed and characterized by their approaches to simulate steel-concrete interface behaviour allowing either full or partial composite action. Non-linear interface or joint elements are introduced between steel and concrete to simulate partial composite action that allows steel-concrete in-plane slip or out of plane separation. The properties of such interface/joint elements are optimised through extensive parametric FE analysis using experimental results to achieve reliable and accurate simulation of actual steel-concrete interaction in a wall. The performance of developed FE models is validated through small-scale model tests. FE models are found to simulate strength, stiffness and strain characteristics reasonably well. The performance of a model with joint elements connecting steel and concrete layers is found better than full composite (without interface or joint elements) and other models with interface elements. The proposed FE model can be used to simulate the shear behaviour of composite walls in practical situation.

• 한국정보통신학회논문지
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• 제8권3호
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• pp.645-653
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• 2004

수중 어류의 행동이나 현상을 예측하여 시각화하기 위해서는 어류의 탐지와 어류반응행동의 파악이 우선 이루어져야 한다. 수중이라는 다변적인 환경요인이 현장 계측을 매우 어렵게 하거나 어류의 행동이 비선형적으로 복잡하고 혼돈스러우므로 기존의 단순한 그래픽처리는 실제 수중현상간의 차이를 극복하지 못해왔던 실정이다. 이에 본 논문에서는 매우 복잡 다양한 어류행동반응의 패턴에 대하여 기존의 연구에서 제안된 혼돈이론을 응용한 어류반응행동 모델을 이용하여 시각화 도구를 제안함으로써 수중의 어류이동현상을 예측하거나 평가, 또는 보다 더 정확히 분석하는 자료를 얻을 수 있게 구현하였다. 아울러, 어탐 디스플레이를 동시에 적용하여 사용자에게 반응에 따르는 어류의 탐지상황도 제공하였다. 제안된 시각화 도구를 평가하기 위하여 현장 계측된 어류의 이동 정보와 비교한 결과, 제안된 시각화 도구는 사실성 높은 어류 행동과 시각적인 이해도를 높일 수 있음을 확인 할 수 있었다.

• 한국학교ㆍ지역보건교육학회지
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• 제17권2호
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• pp.71-81
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• 2016

Objectives: The objective and aim of this research is to cultivate a problem-solving ability by analysing the factors that negatively impact on filming sexual behaviour by adolescent. Methods: This research mainly refer to the secondary reference which is conducted a survey of all over the country by National Youth Policy Institute. 3,963 students on the register who participated in survey between 12th of June in 2014 and 15th of July in 2014 was nominated as final recipient for research. Results: Firstly, it has been shown that students who have watched sexual video have more experienced at filming sexual behaviour. In the area of stimulation(p<0.01) and emulation/sharing(p<0.001) except to violation of human rights, adolescent who has experienced at filming sexual behaviour significantly gains more high score than adolescent who does not have experienced statistically. Secondly, as a result of analysis the factors which negatively impact on filming sexual behaviour by adolescent with Binary logistic regression analysis, the adolescent who have shared sexual video was impacted on having an experience at filming sexual behaviour. and the adolescent who had sexual conversation was impacted on having an experience at filming sexual behaviour. Conclusion: A local autonomous entity and school should enforce systematic health education and practical management of mass media rather than unconditional restriction of adolescent's use of smart phone. To carry out this, the state and a local autonomous entity should urge plan for support for settling the instructive environment about using smart phone.

• Geomechanics and Engineering
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• 제2권1호
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• pp.1-18
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• 2010

The analysis of structure response and design of buried structures subjected to dynamic destructive loads have been receiving increasing interest due to recent severe damage caused by strong earthquakes and terrorist attacks. For a comprehensive design of buried structures subjected to blast loads to be conducted, the whole system behaviour including simulation of the explosion, propagation of shock waves through the soil medium, the interaction of the soil with the buried structure and the structure response needs to be simulated in a single model. Such a model will enable more realistic simulation of the fundamental physical behaviour. This paper presents a complete model simulating the whole system using the finite element package ABAQUS/Explicit. The Arbitrary Lagrange Euler Coupling formulation is used to model the explosive charge and the soil region near the explosion to eliminate the distortion of the mesh under high deformation, while the conventional finite element method is used to model the rest of the system. The elasto-plastic Drucker-Prager Cap model is used to model the soil behaviour. The explosion process is simulated using the Jones-Wilkens-Lee equation of state. The Concrete Damage Plasticity model is used to simulate the behaviour of concrete with the reinforcement considered as an elasto-plastic material. The contact interface between soil and structure is simulated using the general Mohr-Coulomb friction concept, which allows for sliding, separation and rebound between the buried structure surface and the surrounding soil. The behaviour of the whole system is evaluated using a numerical example which shows that the proposed model is capable of producing a realistic simulation of the physical system behaviour in a smooth numerical process.

• Geomechanics and Engineering
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• 제28권2호
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• pp.117-133
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• 2022

Determination of the mechanical behaviour of jointed rock masses has been a challenge for rock engineers for decades. This problem is more pronounced for non-persistent jointed rock masses due to complicated interaction of rock bridges on the overall behaviour. This paper aims to study the effect of a non-persistent joint set configuration on the mechanical behaviour of rock materials under both uniaxial and biaxial compression tests using a discrete element code. The numerical simulation of biaxial compressive strength of rock masses has been challenging in the past due to shortcomings of bonded particle models in reproducing the failure envelope of rock materials. This problem was resolved in this study by employing the flat-joint contact model. The validity of the numerical model was investigated through a comprehensive comparative study against physical uniaxial and biaxial compression experiments. Good agreement was found between numerical and experimental tests in terms of the recorded peak strength and the failure mode in both loading conditions. Studies on the effect of joint orientation on the failure mode showed that four zones of intact, transition to block rotation, block rotation and transition to intact failure occurs when the joint dip angle varies from 0° to 90°. It was found that the applied confining stress can significantly alter the range of these zones. It was observed that the minimum strength occurs at the joint dip angle of around 45 degrees under different confining stresses. It was also found that the joint orientation can alter the post peak behaviour and the lowest brittleness was observed at the block rotation zone.

• Geomechanics and Engineering
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• 제34권3호
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• pp.317-328
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• 2023

The soil behaviour can be represented by numerical modelling of element testing using diverse constitutive models. However, not all constitutive models allow the simulation of the stress-strain response at the critical state in granular soils with both contractive and dilative behaviour. Moreover, the accuracy of these models depends highly on the quality of the experimental data used for their calibration. This study addresses the modelling of the critical state behaviour of an alluvial natural soil from the Lower Tagus Valley (south of Portugal), known as TP-Lisbon sand, using the NorSand constitutive law. For this purpose, a series of numerical simulations of element testing was carried out using two algorithms performed in Visual Basic (VB) and Fast Lagrangian Analysis of Continua (FLAC). Moreover, this study presents the characterisation of of NorSand parameters from an accurate experimental programme based on triaxial and bender element testing. This experimental program allowed defining: (i) the critical state locus, (ii) the stress-dilatancy, and (iii) the soil elasticity of TP-Lisbon sand -all fundamental to calibrate the contractive and dilative behaviour of such alluvial soil. The results revealed a good agreement between experimental data and NorSand simulations using VB and FLAC. Therefore, this study showed that the quality of laboratory testing procedures and its good interpretation enables NorSand constitutive law to capture representatively the non-associated plastic strains, often expressed by the state parameter, allowing a representation of soil behaviour of alluvial soils within the critical state soil mechanics framework for different state parameters.

• 아동학회지
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• 제2권
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• pp.17-30
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• 1981

This study is designed to analyze the child's behaviour development and consider parent's expectation toward it. In the research of the aspect of child's behaviour development, first, this study will analyze the change and development a child shows according to his age, sex, and the community where he is brought up, and then, the relationship between child's behaviour development and parent's expectation toward it. (1) Child's Behaviour Development. a) According to Age. At the age of three ; In such behaviours as wiping nose, dressing, brushing teeth, putting on coat alone, going to toilet for B.M., going on errands, and playing contentedly alone, washing hands, greeting his elders, a child at the age of three to four shows a rapid development, and therefore it seems better to train a child in these behaviors age of three. At the age of four ; In such behaviors sharing cakes with friends, riding on a tricycle, a child shows great development, at the age of four to five, and therefore it seems better to train him in them at the age of four. At the age of five ; In such behaviors as combing hair, putting toys away in proper place, telephoning a child shows great development at the age of five to six, and therefore it seems better to train him in them at the age of five. b) According to sex and community. As a whole, there is little difference between sexes and the communities. It can be estimated from this that sex or the community has on the whole no great influence on the basic aspects of child's behavior development. (2) Parent's expectation. On the whole parent's expectation falls short of a child's development in behaviors ; especially, bathing himself, dressing, going to toilet for B.M, going to toilet to urinate, telephoning, etc. This tendency is consficuous in the case of three or four year old children. This results from parent's protecting in excess their children and reducing the opportunities to encourage the children's independence by delaying the babyhood. (3) The relationship between child's behaviour development and parent's expectation. a) On the whole, the behaviour of a child is at a higher level than parent's expectation. b) As a child grows from three years to six, his behaviour develops on the whole in accordance with the increase of parent's expectation. But the level of the former is lower than that of the latter. c) According to computing a coefficient of correlation is as follows. 3 years old ; .84 4 years old ; .90 5 years old ; .87 6 years old ; .89 It shows there is a high correlation between child's Behaviour and Parent's Expectation.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 춘계학술대회 논문집
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• pp.455-456
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• 2010