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Full-Text Articles in Social and Behavioral Sciences

Computational Simulation Of Eccentrically Loaded Circular Thin-Walled Concrete-Filled Double Steel Tubular Slender Columns, Mizan Ahmed, Qing Liang, Vipulkumar Patel, Muhammad N. S Hadi Jan 2020

Computational Simulation Of Eccentrically Loaded Circular Thin-Walled Concrete-Filled Double Steel Tubular Slender Columns, Mizan Ahmed, Qing Liang, Vipulkumar Patel, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

The concrete confinement provided by the circular steel tubes improves the performance of circular concretefilled double steel tubular (CFDST) columns, which have increasingly been employed as high-performance structural members in tall buildings. This paper presents computational and design models for the simulation and design of high strength CFDST slender columns composed of circular thin-walled sections that are eccentrically loaded. The formulation of the computational model is described, which takes into account the influences of concrete confinement, geometric imperfection, second-order, gradual plasticity of steel, and geometric and material nonlinearities. The inverse quadratic method is implemented in computational algorithms which solve the …


Nonlinear Analysis Of Square Concrete-Filled Double Steel Tubular Slender Columns Incorporating Preload Effects, Mizan Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi Jan 2020

Nonlinear Analysis Of Square Concrete-Filled Double Steel Tubular Slender Columns Incorporating Preload Effects, Mizan Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

Thin-walled square and circular hollow steel tubes are designed to support the permanent and construction loads of several upper composite floors before filling the concrete into the tubes to form concrete-filled double steel tubular (CFDST) columns. The influences of preloads acting on the steel tubes on the structural responses of slender square CFDST columns have not been investigated either experimentally or numerically. This paper presents a fiber-based computational model for the determination of the interaction behavior of local and global buckling in axially and eccentrically loaded CFDST thin-walled square slender columns including preload effects. The computational modeling method accounts for …


Experimental And Numerical Investigations Of Eccentrically Loaded Rectangular Concrete-Filled Double Steel Tubular Columns, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi Jan 2020

Experimental And Numerical Investigations Of Eccentrically Loaded Rectangular Concrete-Filled Double Steel Tubular Columns, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

Rectangular concrete-filled double steel tubular (CFDST) columns have increasingly been utilized in high-rise buildings to support heavy loads. However, the responses of eccentrically loaded rectangular CFDST short columns have rarely been studied. This paper reports experimental and numerical investigations into the behavior of rectangular thin-walled short CFDST columns composed of a rectangular inner steel tube loaded eccentrically. Tests on rectangular and square CFDST short columns under eccentric loading and axial loading were carried out to examine their responses to various design parameters, including the cross-sectional dimensions, loading eccentricity, and width-to-thickness ratios of the external and internal tubes. The experimental program …


Experimental And Numerical Studies Of Square Concrete-Filled Double Steel Tubular Short Columns Under Eccentric Loading, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi Jan 2019

Experimental And Numerical Studies Of Square Concrete-Filled Double Steel Tubular Short Columns Under Eccentric Loading, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

Square concrete-filled double steel tubular (CFDST) beam-columns consisting of an internal circular steel tube have increasingly been utilized in composite building structures because of their high structural performance. This paper describes experimental and numerical studies on the structural responses of square thin-walled CFDST columns loaded eccentrically. Tests on twenty short square CFDST columns were undertaken that included sixteen columns under eccentric loading and four columns under concentric loading. The parameters examined in the experiments included the cross-sectional dimensions, the width-to-thickness ratios of outer and internal tubes and loading eccentricity. The measured ultimate strengths, load-shortening responses, load-lateral displacement curves, stress-strain curves …


Local-Global Interaction Buckling Of Square High Strength Concrete-Filled Double Steel Tubular Slender Beam-Columns, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi Jan 2019

Local-Global Interaction Buckling Of Square High Strength Concrete-Filled Double Steel Tubular Slender Beam-Columns, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

High-strength square concrete-filled double steel tubular (CFDST) slender beam-columns with a circular internal steel tube subjected to eccentric loads may undergo interaction local-global buckling. No computational studies on the interaction local-global buckling of slender square CFDST beam-columns have been reported and their behavior has not been fully understood. This paper describes a mathematical model for the simulation of the interaction local-global buckling behavior of square high-strength CFDST slender beam-columns under axial compression in combination with uniaxial bending. The mathematical model is formulated by the fiber approach, accounting for confinement provided by the internal circular steel tube, and geometric and material …


Numerical Analysis Of Axially Loaded Circular High Strength Concrete-Filled Double Steel Tubular Short Columns, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi Jan 2019

Numerical Analysis Of Axially Loaded Circular High Strength Concrete-Filled Double Steel Tubular Short Columns, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

Circular high-strength concrete-filled double steel tubular (CFDST) columns are high performance members where the internal and external steel tubes offer significant confinement to the concrete infill. The confinement remarkably improves the concrete compressive strength and ductility. However, no fiber element models have been formulated for computing the responses of CFDST columns with circular steel tubes filled with high-strength concrete incorporating accurate confinement to the core and sandwiched concrete. In this paper, a new fiber-based numerical model is developed that computes the axial load-strain responses of circular high-strength CFDST short columns under axial loading. Based on existing experimental results, a new …


Behavior Of Eccentrically Loaded Double Circular Steel Tubular Short Columns Filled With Concrete, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi Jan 2019

Behavior Of Eccentrically Loaded Double Circular Steel Tubular Short Columns Filled With Concrete, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

Circular concrete-filled double steel tubular (CFDST) columns in high-rise building structures possess high ductility and strength performance owing to the concrete confinement exerted by the external and internal circular steel tubes. However, the behavior of circular CFDST short columns that are loaded eccentrically has not been investigated either experimentally or numerically. Particularly, numerical studies on the moment-curvature responses, strength envelopes, confinement effects and moment distributions in circular CFDST beam-columns have not been reported. In this paper, experimental and computational investigations into the structural responses of circular CFDST short columns loaded eccentrically are presented. Nineteen short circular CFDST columns with various …


Heat Transfer Analysis Of An Integrated Double Skin Facade And Phase Change Material Blind System, Yilin Li, Jo Darkwa, Georgios Kokogiannakis Jan 2017

Heat Transfer Analysis Of An Integrated Double Skin Facade And Phase Change Material Blind System, Yilin Li, Jo Darkwa, Georgios Kokogiannakis

Faculty of Engineering and Information Sciences - Papers: Part B

In this study, the heat transfer in an integrated double skin facade (DSF) and phase change material (PCM) blind system has been theoretically analysed. Both heat transfer and airflow models with CFD methods have been developed for the integrated DSF and PCM blind system. Data from an existing typical DSF building have been obtained in order to define input parameters for the simulation exercise and validate the numerical models. The temperature and velocity fields in DSF with the PCM blind system has been predicted under overheating scenario using the ANSYS Workbench FLUENT software and been compared with case of conventional …


Design Of Geometric Parameters Of A Double-Sided Linear Induction Motor With Ladder Secondary And A Consideration For Reducing Cogging Force, Mochammad Rusli, Christopher David Cook Jan 2015

Design Of Geometric Parameters Of A Double-Sided Linear Induction Motor With Ladder Secondary And A Consideration For Reducing Cogging Force, Mochammad Rusli, Christopher David Cook

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, design of the physical of double-sided linear induction motor with ladder secondary is presented. It has aim to obtain the high-precision of DSLIM for the linear slow speed applications. One of limiting factor for precision linear movement is cogging force. The efforts in reducing the cogging action in rotary induction motor has been conducted very well. However, the cogging force reduction in the DSLIM with ladder secondary has not been done before. The DSLIM provide a great advantages for LIM-driven wheel vehicles for specific applications, for example vehicles that are used in over short distances, e.g. at …


Absorption Enhancement In Double-Sided Nanocone Hole Arrays For Solar Cells, Xu Zhang, Yanguang Yu, Jiangtao Xi, Yile Wang, Xiao-Hong Sun Jan 2015

Absorption Enhancement In Double-Sided Nanocone Hole Arrays For Solar Cells, Xu Zhang, Yanguang Yu, Jiangtao Xi, Yile Wang, Xiao-Hong Sun

Faculty of Engineering and Information Sciences - Papers: Part A

Enhancing light absorption in thin-film silicon solar cells is important for improving light harvesting efficiency and reducing manufacture cost. In this paper, we introduce a double-sided nanocone hole (NCH) array structure for solar cells by extending a model suggested by Wang et al (2012 Nano Lett. 12 1616). The top-sided NCH structure is mainly used for increasing the antireflection of incident light, and the bottom-sided NCH structure for enhancing light trapping in the near-infrared spectrum. The theoretical analysis is performed on the proposed structure, from which the optimal geometric parameters of the structure are determined. The performance analysis shows that …


Molecular Weight Distribution Of Network Strands In Double Network Hydrogels Estimated By Mechanical Testing, Hai Xin, Hugh Ralph Brown, Geoffrey M. Spinks Jan 2014

Molecular Weight Distribution Of Network Strands In Double Network Hydrogels Estimated By Mechanical Testing, Hai Xin, Hugh Ralph Brown, Geoffrey M. Spinks

Faculty of Engineering and Information Sciences - Papers: Part A

The remarkably high toughness of double network (DN) hydrogels is related to the energy dissipation that occurs due to the scission of network strands in the most tightly crosslinked of its two interpenetrating networks. The loading curve during tensile testing of DN hydrogels usually takes a complex shape and sometimes shows yielding. Wang and Hong recently proposed a model [1] based on the successive scission of the shortest remaining elastically active strands during tensile loading that predicts the shape of the loading curve of one DN hydrogel reasonably well. In the present study, the model was modified slightly and applied …


Behavior Of Hybrid Frp-Concrete-Steel Double-Skin Tubular Columns With A Square Outer Tube And A Circular Innert Tube Subjected To Axial Compression, Tao Yu, J G. Teng Jan 2013

Behavior Of Hybrid Frp-Concrete-Steel Double-Skin Tubular Columns With A Square Outer Tube And A Circular Innert Tube Subjected To Axial Compression, Tao Yu, J G. Teng

Faculty of Engineering and Information Sciences - Papers: Part A

Hybrid fiber-reinforced polymer (FRP) concrete steel, double skin tubular columns (DSTCs) are a new form of hybrid columns. The most common sectional form of hybrid DSTCs consists of a layer of concrete sandwiched between a circular inner steel tube and a circular outer FRP tube whose fiber directions are close to the hoop detection to provide effective confinement to the concrete. Much recent research has been conducted on circular hybrid DSTCs, which has demonstrated that the combination of the three constituent materials leads to several advantages not available with existing forms of columns. In practical applications, for aesthetic and other …


Effect Of First Network Topology On The Toughness Of Double Network Hydrogels, Hai Xin, Sureyya Saricilar, Hugh Ralph Brown, Philip G. Whitten, Geoffrey Maxwell Spinks Jan 2013

Effect Of First Network Topology On The Toughness Of Double Network Hydrogels, Hai Xin, Sureyya Saricilar, Hugh Ralph Brown, Philip G. Whitten, Geoffrey Maxwell Spinks

Faculty of Engineering and Information Sciences - Papers: Part A

The fracture toughness of a double network (DN) hydrogel is shown here to be directly proportional to the toughness of the first-formed network. A series of DN gels was prepared in which the cross-link density of the first (tighter) network was controlled by varying the monomer and cross-linker concentrations. The toughness, tensile strength and elastic modulus of the DN gels increased significantly with an increase in the cross-link density of the first network and with identically prepared second networks. Moreover, the toughness of the double network was found to be linearly related to the toughness of the first network with …


Optical Image Encryption Based On Chaotic Baker Map And Double Random Phase Encoding, Ahmed M. Elshamy, Ahmed N. Z Rashed, Abd El-Naser A. Mohamed, Osama S. Faragalla, Yi Mu, Saleh A. Alshebeili, F E Abd El-Samie Jan 2013

Optical Image Encryption Based On Chaotic Baker Map And Double Random Phase Encoding, Ahmed M. Elshamy, Ahmed N. Z Rashed, Abd El-Naser A. Mohamed, Osama S. Faragalla, Yi Mu, Saleh A. Alshebeili, F E Abd El-Samie

Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents a new technique for optical image encryption based on chaotic Baker map and Double Random Phase Encoding (DRPE). This technique is implemented in two layers to enhance the security level of the classical DRPE. The first layer is a pre-processing layer, which is performed with the chaotic Baker map on the original image. In the second layer, the classical DRPE is utilized. Matlab simulation experiments show that the proposed technique enhances the security level of the DRPE, and at the same time has a better immunity to noise.


Double Space-Time Transmit Diversity For Very High Data Rate Mb-Ofdm Uwb Systems, Ngoc P. Le, Le C. Tran, Farzad Safaei Jan 2012

Double Space-Time Transmit Diversity For Very High Data Rate Mb-Ofdm Uwb Systems, Ngoc P. Le, Le C. Tran, Farzad Safaei

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, we investigate a multiband-orthogonal frequency division multiplexing ultra-wideband (MB-OFDM UWB) system with very high data rates (VHDR) of several gigabits per second (Gbps). We propose a DSTTD-based VHDR MB-OFDM UWB system by incorporating a double space-time transmit diversity (DSTTD) scheme into the conventional MB-OFDM UWB system. At the receiver, an efficient soft-demapper that takes into consideration the noise enhancement due to a zero-forcing equalization is developed. Numerical simulations of the proposed system at a very high data rate of 2.Gbps over the IEEE 802.15.3a channel models are implemented. The simulation results show that this system could achieve …


Estimation Of Breeding Values For Mean And Dispersion, Their Variance And Correlation Using Double Hierarchical Generalized Linear Models, M Felleki, D Lee, Y Lee, A R. Gilmour, L Ronnegard Jan 2012

Estimation Of Breeding Values For Mean And Dispersion, Their Variance And Correlation Using Double Hierarchical Generalized Linear Models, M Felleki, D Lee, Y Lee, A R. Gilmour, L Ronnegard

Faculty of Engineering and Information Sciences - Papers: Part A

The possibility of breeding for uniform individuals by selecting animals expressing a small response to environment has been studied extensively in animal breeding. Bayesian methods for fitting models with genetic components in the residual variance have been developed for this purpose, but have limitations due to the computational demands. We use the hierarchical (h)-likelihood from the theory of double hierarchical generalized linear models (DHGLM) to derive an estimation algorithm that is computationally feasible for large datasets. Random effects for both the mean and residual variance parts of the model are estimated together with their variance/covariance components. An important feature of …


Hybrid Frp-Concrete-Steel Double-Skin Tubular Columns: Cyclic Axial Compression Tests, Tao Yu, Yu-Bo Cao, Bing Zhang, J G. Teng Jan 2012

Hybrid Frp-Concrete-Steel Double-Skin Tubular Columns: Cyclic Axial Compression Tests, Tao Yu, Yu-Bo Cao, Bing Zhang, J G. Teng

Faculty of Engineering and Information Sciences - Papers: Part A

Hybrid FRP-concrete-steel double-skin tubular columns (hybrid DSTCs) are a new form of hybrid columns recently developed at The Hong Kong Polytechnic University. A hybrid DSTC consists of an inner steel tube, an outer FRP tube and a concrete infill between the two tubes. Hybrid DSTCs possess many important advantages over existing column forms, including their excellent corrosion resistance and excellent seismic resistance. While a large amount of research has been conducted on the monotonic behavior of this novel form of columns, only a limited amount of work has been conducted on their behavior under cyclic loading. This paper presents the …


Behaviour Of Hybrid Double-Skin Tubular Columns Subjected To Combined Axial Compression And Cyclic Lateral Loading, Bing Zhang, J G. Teng, Tao Yu Jan 2012

Behaviour Of Hybrid Double-Skin Tubular Columns Subjected To Combined Axial Compression And Cyclic Lateral Loading, Bing Zhang, J G. Teng, Tao Yu

Faculty of Engineering and Information Sciences - Papers: Part A

Hybrid FRP-concrete-steel double-skin tubular columns (hybrid DSTCs) are a new form of hybrid columns developed at The Hong Kong Polytechnic University. They consist of an outer tube made of fibre reinforced polymer (FRP) and an inner tube made of steel, with the space between filled with concrete. In these hybrid DSTCs, the three constituent materials are optimally combined to achieve several advantages not available with existing forms of columns, including their superior corrosion and seismic performance. This paper presents the test results of a series of large-scale hybrid DSTCs subjected to combined axial and cyclic lateral loads, with an emphasis …


Flexural Behaviour Of Hybrid Frp-Concrete-Steel Double Skin Tubular Members, T Yu, Y L. Wong, J G. Teng, S L. Dong, E S.S Lam Jan 2006

Flexural Behaviour Of Hybrid Frp-Concrete-Steel Double Skin Tubular Members, T Yu, Y L. Wong, J G. Teng, S L. Dong, E S.S Lam

Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents the results of an experimental study on the flexural behavior of a new type of hybrid FRP-concrete-steel member as well as results from a corresponding theoretical model based on the plane section assumption and the fiber element approach. This new type of hybrid member is in the form of a double-skin tube, composed of a steel inner tube and an FRP outer tube with a concrete infill between the two tubes, and may be employed as columns or beams. The parameters examined in this study include the section configuration, the concrete strength, and the thicknesses of the …


Influence Of In-Plane Displacement And Double-Aperture Orientation On Slope Fringe Formation In Double-Shearing-Aperture Speckle Interferometry, K F. Wang, A Kiet Tieu, Enbang Li Jan 2000

Influence Of In-Plane Displacement And Double-Aperture Orientation On Slope Fringe Formation In Double-Shearing-Aperture Speckle Interferometry, K F. Wang, A Kiet Tieu, Enbang Li

Faculty of Engineering and Information Sciences - Papers: Part A

The influence of the in-plane displacement and double-aperture orientation on the slope fringe formation in double-shearing-aperture speckle interferometry is discussed in detail. The research results show that the two in-plane displacement components, one parallel to and the other perpendicular to the shearing direction, have an influence on the slope fringe formation and that the double-aperture orientation also has an important influence on the slope fringe formation. A theoretical analysis and experimental results are presented. The experimental results are in good agreement with the theoretical analysis.