• 제목/요약/키워드: Behaviour pattern

검색결과 161건 처리시간 0.023초

Numerical simulation and experimental investigation of the shear mechanical behaviors of non-persistent joint in new shear test condition

  • Wang, Dandan;Zhang, Guang;Sarfarazi, Vahab;Haeri, Hadi;Naderi, A.A.
    • Computers and Concrete
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    • 제26권3호
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    • pp.239-255
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    • 2020
  • Experimental and discrete element method were used to investigate the effects of joint number and its angularities on the shear behaviour of joint's bridge area. A new shear test condition was used to model the gypsum cracks under shear loading. Gypsum samples with dimension of 120 mm×100 mm×50 mm were prepared. the length of joints was 2cm. in experimental tests, the joint number is 1, 2 and 3 and its angularities change from 0° to 90° with increment of 45°. Assuming a plane strain condition, special rectangular models are prepared with dimension of 120 mm×100 mm. similar to joints configuration in experimental test, 9 models with different joint number and joint angularities were prepared. This testing show that the failure process is mostly governed by the joint number and joint angularities. The shear strengths of the specimens are related to the fracture pattern and failure mechanism of the discontinuities. The shear behaviour of discontinuities is related to the number of induced tensile cracks which are increased by increasing the rock bridge length. The strength of samples decreases by increasing the joint number and joint angularities. Failure pattern and failure strength are similar in both of the experimental test and numerical simulation.

시간대별 행동패턴에 따른 공간시스템에 관한 연구 - 현대건축에 나타난 다이어그램을 통한 공간구축 사례를 중심으로 - (A Study on the Space Systems on the basis of Time-based Activity Pattern - Focusing on Spatialization Cases by Diagrams in Contemporary Architecture -)

  • 강은주;김종진
    • 한국실내디자인학회:학술대회논문집
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    • 한국실내디자인학회 2005년도 추계학술발표대회 논문집
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    • pp.143-146
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    • 2005
  • Human activity pattern has been changed as the contemporary urban society changes. Diverse activities repeat regular patterns as time passes. Diagram is a simple drawing which aims to organize and unify various information. The elements of the social behaviour could be spatialized by means of diagram applications. By using diagrams, architects understand contemporary urban society and form new space conditions. Time-based activity patterns consists of activity pattern in a restricted space and in urban structure for space use. Activity patterns for different time zones are explained by two types of diagrams, space occupation and flexibility of space, By the characteristic of space system structred by these diagrams, activities and programs are rearranged and variety of space is allowed through flexibility. Also, programs are mixed to apply to simultaneous occurrence of ever-changing human activities.

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중소 ICT건설기업 조직원의 셀프리더십이 심리적 임파워먼트 통하여 조직시민행동과 조직신뢰에 미치는 영향 (The Effect of Employee's Self Leadership of Construction Company on Organization Citizenship Behaviour and Organizational Trust through Psychology Empowerment)

  • 최재영;황찬규
    • 디지털산업정보학회논문지
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    • 제15권3호
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    • pp.207-223
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    • 2019
  • This study aims to explore the casual relation between construction company employees' Self-Leadership and two variables: Organization Citizenship Behaviour and Organizational Trust through Psychology Empowerment. To explain in details, this study examines how the independent variable, Self Leadership, with its behavior-focused, natural reward and constructive thought pattern strategies, affects the dependent variable, Organization Citizenship Behavior and Organizational Trust through the intervening variable, Psychology Empowerment. A survey was conducted on current employees of construction companies in metropolitan areas to empirically examine the research model. The result of study hypothesis on Self-Leadership is as follows; first, Self-Leadership showed a positive effect on Psychology Empowerment, Organization Citizenship Behaviour and Organizational Trust. Second, Psychology Empowerment showed a positive effect on Organization Citizenship Behaviour. Third, Psychology Empowerment showed a positive effect on Organizational Trust. The capacity of individuals is critical when it comes to competitiveness of construction companies. When employees willingly participate in building trust within the company, the work place will become more and more constructive; based on trust, efficiency will increase because people from different processes can work together and performance will also improve even when project managers are absent because others could help their role instead, thus driving more efficient human resource management to the company. To conclude, a company's vision can be spread wide and far when their employees engage themselves in Learning Organization with Self Leadership. They will also be satisfied with their work through improving interpersonal relationship at work.

Research Advances on Tension Buckling Behaviour of Aerospace Structures: A Review

  • Datta, Prosun Kumar;Biswas, Sauvik
    • International Journal of Aeronautical and Space Sciences
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    • 제12권1호
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    • pp.1-15
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    • 2011
  • This paper reviews most of the research done in the field of tensile buckling characteristics pertaining to aerospace structural elements with special attention to local buckling and parametric excitation due to periodic loading on plate and shell elements. The concepts of buckling in aerospace structures appear as the result of the application of a global compressive applied load or shear load. A less usual situation is the case, in which a global tensile stress creates buckling instability and the formation of complex spatial buckling pattern. In contrast to the case of a pure compression or shear load, here the applied macroscopic load has no compressive component and is thus globally stabilizing. The instability stems from a local compressive stress induced by the presence of a defect, such as a crack or a hole, due to partial or non-uniform applied load at the far end. This is referred to as tensile buckling. This paper discusses all aspects of tensile buckling, theoretical and experimental. Its far reaching applications causing local instability in aerospace structural components are discussed. The important effects on dynamic stability behaviour under locally induced periodic compression have been identified and influences of various parameters are discussed. Experimental results on simple and combination resonance characteristics on plate structures due to tensile buckling effects are elaborated.

Demand-feeding and Locomotor Circadian Rhythms in the Red sea bream, Pagrus major

  • Choe Yong-Gwon;Choi Jae-Eun;Roh Duk-Whan;Choi Cheol-Young
    • Fisheries and Aquatic Sciences
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    • 제4권3호
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    • pp.130-137
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    • 2001
  • In the present study, the locomotor and feeding activities of single red sea bream, Pagrus major were simultaneously investigated to examine the existence of such dual behaviour. Seven red sea bream of 13cm body length on average were placed individually in 35L tanks equipped with an infrared sensor and a newly developed demand-feeding device. Fish were exposed to a light: dark 12: 12h cycle and constant darkness (DD) to study endogenous rhythmicity. Under LD 12: 12 h, the daily pattern of behaviour differed between individual fish; some red sea bream were diurnal and others were nocturnal. Futhermore, some of them displayed an extraordinary flexibility in phasing because they were dark active but light feeding, and vice versa. Under DD, red sea bream showed free-running rhythms for locomotor activity and feeding. These results indicate that the type of phasing of locomotor activity did not necessarily decide the feeding phase; much of this is explained by the fact that red sea bream were demand-fed. Flexibility in phasing and a certain degree of independence between locomotor and feeding activities could be seen as an adaptative response of the highly adaptable circadian rhythms of fish.

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Nonlinear interaction behaviour of infilled frame-isolated footings-soil system subjected to seismic loading

  • Agrawal, Ramakant;Hora, M.S.
    • Structural Engineering and Mechanics
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    • 제44권1호
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    • pp.85-107
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    • 2012
  • The building frame and its foundation along with the soil on which it rests, together constitute a complete structural system. In the conventional analysis, a structure is analysed as an independent frame assuming unyielding supports and the interactive response of soil-foundation is disregarded. This kind of analysis does not provide realistic behaviour and sometimes may cause failure of the structure. Also, the conventional analysis considers infill wall as non-structural elements and ignores its interaction with the bounding frame. In fact, the infill wall provides lateral stiffness and thus plays vital role in resisting the seismic forces. Thus, it is essential to consider its effect especially in case of high rise buildings. In the present research work the building frame, infill wall, isolated column footings (open foundation) and soil mass are considered to act as a single integral compatible structural unit to predict the nonlinear interaction behaviour of the composite system under seismic forces. The coupled isoparametric finite-infinite elements have been used for modelling of the interaction system. The material of the frame, infill and column footings has been assumed to follow perfectly linear elastic relationship whereas the well known hyperbolic soil model is used to account for the nonlinearity of the soil mass.

Comparison of macrosynthetic and steel FRC shear-critical beams with similar residual flexure tensile strengths

  • Ortiz-Navas, Francisco;Navarro-Gregori, Juan;Leiva, Gabriel;Serna, Pedro
    • Structural Engineering and Mechanics
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    • 제76권4호
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    • pp.491-503
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    • 2020
  • This study extends previous experimental research on the shear behaviour of macrosynthetic fibre-reinforced concrete beams and compares them to steel fibre-reinforced concrete beams with similar mechanical and geometrical properties. This work employed two fibre types: 60/0.9 (long/diameter) double hooked-end steel fibre and 60/85 monofilament polypropylene fibre. Beams were tested by shear loading covering parameters, such as two different cross-section widths, two shear-span-to-effective-depth ratios, two fibre types and using repetitions with and without transverse reinforcement. For quantitative comparison purposes, crack pattern evolution was studied along increasing loads levels. Effects were studied by photogrammetry, including influence of fibres on crack propagation in uncracked and dowel zones, influence of fibres on stirrup behaviour, and shear deformation or kinematics of critical shear cracks. The results evidenced similar effectiveness for both fibre types in controlling shear crack propagation and horizontal dowel cracking. Both fibres provided similar shear ductility and shear deflections. Consequently, the authors confirm that residual flexural tensile strengths are a convenient parameter for characterising the shear behaviour of fibre-reinforced concrete beams.

A review of experimental and numerical studies on crack growth behaviour in rocks with pre-existing flaws

  • G. Sivakumar;V.B. Maji
    • Geomechanics and Engineering
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    • 제35권4호
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    • pp.333-366
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    • 2023
  • Rock as a mass generally exhibits discontinuities, commonly witnessed in rock slopes and underground structures like tunnels, rock pillars etc. When these discontinuities experiences loading, a new crack emerges from them which later propagates to a macro scale level of failure. The failure pattern is often influenced by the nature of discontinuity, geometry and loading conditions. The study of crack growth in rocks, namely its initiation and propagation, plays an important role in defining the true strength of rock and corresponding failure patterns. Many researchers have considered the length of the discontinuity to be fully persistent on rock or rock-like specimens by both experimental and numerical methods. However, only during recent decades, there has been a substantial growth in research interest with non-persistent discontinuities where the crack growth and its propagation phenomenon were found to be much more complex than persistent ones. The non-persistence fractures surface is generally considered to be open and closed. Compared to open flaws, there is a difference in crack growth behaviour in closed or narrow flaws due to the effect of surface closure between them. The present paper reviews the literature that has contributed towards studying the crack growth behaviour and its failure characteristics on both open and narrow flaws subjected to uniaxial and biaxial compression loading conditions.

A Secure Authentication Method for Smart Phone based on User's Behaviour and Habits

  • Lee, Geum-Boon
    • 한국컴퓨터정보학회논문지
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    • 제22권9호
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    • pp.65-71
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    • 2017
  • This paper proposes a smart phone authentication method based on user's behavior and habit that is an authentication method against shoulder surfing attack and brute force attack. As smart phones evolve not only storage of personal data but also a key means of financial services, the importance of personal information security in smart phones is growing. When user authentication of smart phone, pattern authentication method is simple to use and memorize, but it is prone to leak and vulnerable to attack. Using the features of the smart phone pattern method of the user, the pressure applied when touching the touch pad with the finger, the size of the area touching the finger, and the time of completing the pattern are used as feature vectors and applied to user authentication security. First, a smart phone user models and stores three parameter values as prototypes for each section of the pattern. Then, when a new authentication request is made, the feature vector of the input pattern is obtained and compared with the stored model to decide whether to approve the access to the smart phone. The experimental results confirm that the proposed technique shows a robust authentication security using subjective data of smart phone user based on habits and behaviors.