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Approximation Algorithms For Interference Aware Broadcast In Wireless Networks, Dianbo Zhao, Kwan-Wu Chin 2013 University of Wollongong

Approximation Algorithms For Interference Aware Broadcast In Wireless Networks, Dianbo Zhao, Kwan-Wu Chin

Faculty of Engineering and Information Sciences - Papers: Part A

Broadcast is a fundamental operation in wireless networks and is well supported by the wireless channel. However, the interference resulting from a node's transmission pose a key challenge to the design of any broadcast algorithms/protocols. In particular, it is well known that a node's interference range is much larger than its transmission range and thus limits the number of transmitting and receiving nodes, which inevitably prolong broadcast. To this end, a number of past studies have designed broadcast algorithms that account for this interference range with the goal of deriving a broadcast schedule that minimizes latency. However, these works have …


Block Shear Capacity Of Bolted Connections In Hot-Rolled Steel Plates, Lip H. Teh, Veysel Yazici 2013 University of Wollongong

Block Shear Capacity Of Bolted Connections In Hot-Rolled Steel Plates, Lip H. Teh, Veysel Yazici

Faculty of Engineering and Information Sciences - Papers: Part A

This paper extends the research previously conducted at the University of Wollongong on block shear failure of bolted connections in cold-reduced steel sheets with low ductility to hot-rolled steel plates. It examines the applicability of the basic approach employed for cold-reduced sheet steel bolted connections, which makes use of the so-called active shear planes, to hot-rolled steel plate connections. The active shear planes lie midway between the gross and the net shear planes defined in the steel structures specifications. The paper shows that shear yielding leading to the block shear failure of a bolted connection in a hot-rolled steel gusset …


On The Effects Of Spreading Sequences Over Mimo Systems, Tianle Liu, David A. Stirling, Le Chung Tran, Tadeusz A. Wysocki, Beata J. Wysocki, Prashan Dissanayake Mudiyanselage,, Peter James Vial 2013 University of Wollongong

On The Effects Of Spreading Sequences Over Mimo Systems, Tianle Liu, David A. Stirling, Le Chung Tran, Tadeusz A. Wysocki, Beata J. Wysocki, Prashan Dissanayake Mudiyanselage,, Peter James Vial

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, we develop a Software Defined Radio (SDR) test bed to evaluate the Multiple Access Interference (MAI) effects over SISO and 2 x 1MIMO systems. It can be observed that under asynchronous transmissions, the Gold code leads to the best performance over both systems due to the fact that it has the best correlation properties. We also find the MAI effects in terms of the spreading sequences pairs on MIMO-STS systems. We propose a criterion for selecting promising spreading sequences for MIMO systems. Based on the measured results, we identify pairs of spreading sequences which have improved BER …


Coastal Reservoirs Strategy For Water Resource Development-A Review Of Future Trend, Jianli Liu, Shu-qing Yang, Changbo Jiang 2013 University of Wollongong

Coastal Reservoirs Strategy For Water Resource Development-A Review Of Future Trend, Jianli Liu, Shu-Qing Yang, Changbo Jiang

Faculty of Engineering and Information Sciences - Papers: Part A

Water use and access become a more and more important determinant of environmental equity and human development according to the view held by the UN [1]. Water scarcity is one of the major crises which has overarching implications for other world problems especially poverty, hunger, ecosystem degradation, desertification, climate change, threatening world peace and security [2]. In the decades to come, freshwater consumed by human will get to a tipping point. Many projects and concepts have been proposed and implemented for several years to improve the effectiveness of us-ing water. These research activities can be grouped as: desalination plants; water …


Dynamic Properties Of Sand-Tyre Chip Mixtures, M S. Mashiri, M. Neaz Sheikh, J S Vinod, Hing Ho Tsang 2013 University of Wollongong

Dynamic Properties Of Sand-Tyre Chip Mixtures, M S. Mashiri, M. Neaz Sheikh, J S Vinod, Hing Ho Tsang

Faculty of Engineering and Information Sciences - Papers: Part A

The stockpiling of scrap tyres is a significant environmental hazard and has attracted ample research attention to explore viable solutions to recycling and reuse of scrap tyres. The authors have recently proposed a novel seismic isolation method using sand-tyre chips (STCh) mixture for protecting buildings and infrastructure. Although the static properties of STCh mixture have been extensively studied, the investigation on the dynamic properties of the mixture has been limited. The dynamic properties of STCh mixture are important to its application for seismic protection of infrastructure. This paper presents the dynamic properties (shear modulus and damping ratio) of STCh mixture …


Neutron Generator Burst Timing Measured Using A Pulse Shape Discrimination Plastic Scintillator With Silicon Photomultiplier Readout, R M. Preston, J Eberhardt, J R. Tickner 2013 University of Wollongong

Neutron Generator Burst Timing Measured Using A Pulse Shape Discrimination Plastic Scintillator With Silicon Photomultiplier Readout, R M. Preston, J Eberhardt, J R. Tickner

Faculty of Engineering and Information Sciences - Papers: Part A

An EJ-299-34 plastic scintillator with silicon photomultiplier (SiPM) readout was used to measure the fast neutron output of a pulsed Thermo-Fisher A-325 Deuterium-Tritium sealed tube neutron generator (STNG). The SiPM signals were handled by a prototype digital pulse processing system, based on a free-running analogue to digital converter feeding a digital signal processor (DSP). Pulse shape discrimination was used to distinguish between detected fast-neutrons and gammas. Pulse detection, timing, energy and shape were all processed by the DSP in real-time.


Evaluation Of Damping Modification Factors For Seismic Response Spectra, M. Neaz Sheikh, Hing-Ho Tsang, Saman Yaghmaei-Sabegh, P. Anbazhagan 2013 University of Wollongong

Evaluation Of Damping Modification Factors For Seismic Response Spectra, M. Neaz Sheikh, Hing-Ho Tsang, Saman Yaghmaei-Sabegh, P. Anbazhagan

Faculty of Engineering and Information Sciences - Papers: Part A

Seismic response spectra with structural damping ratio other than nominal 5% (of critical damping) are essential for the design and evaluation of structures in performance-based seismic engineering. Such response spectra are also essential for the design and evaluation of structures with seismic isolation and energy dissipation systems. A number of formulations for damping modification factors (DMF) have been proposed in the literature for scaling the 5% damped response spectra. Dependence of the DMF on several ground motion parameters has also been identified. Few seismic design codes have already incorporated simplified DMF based on these studies. This paper critically reviews the …


Automatic Bdi Plan Recognition From Process Execution Logs And Effect Logs, Hongyun Xu, Bastin Tony Roy Savarimuthu, Aditya Ghose, Evan Morrison, Qiying Cao, Youqun Shi 2013 University of Wollongong

Automatic Bdi Plan Recognition From Process Execution Logs And Effect Logs, Hongyun Xu, Bastin Tony Roy Savarimuthu, Aditya Ghose, Evan Morrison, Qiying Cao, Youqun Shi

Faculty of Engineering and Information Sciences - Papers: Part A

Agent applications are often viewed as unduly expensive to develop and maintain in commercial contexts. Organizations often settle for less sophisticated and more traditional software in place of agent technology because of (often misplaced) fears about the development and maintenance costs of agent technology, and the often mistaken perception that traditional software offers better returns on investment. This paper aims to redress this by developing a plan recognition framework for agent program learning, where behavior logs of legacy applications (or even manually executed processes) are mined to extract a 'draft' version of agent code that could eventually replace these applications …


Effect Of Rice Husk Ash On Workability And Strength Of Concrete, Avinash Babu Srinivasreddy, Timothy J. McCarthy, Eric Lume 2013 University of Wollongong

Effect Of Rice Husk Ash On Workability And Strength Of Concrete, Avinash Babu Srinivasreddy, Timothy J. Mccarthy, Eric Lume

Faculty of Engineering and Information Sciences - Papers: Part A

Rice husk ash (RHA) is an agricultural waste which is a pozzolanic material that can be blended with the cement for manufacturing concrete. Its use can reduce the environmental impact of the cement industry. The present study investigates the chemical and morphological nature of RHA and silica fume (SF). Both can be used to improve strength and durability properties of concrete. Particle size distribution, loss on ignition (LOI), X-ray diffraction analysis, scanning electron microscopic were conducted. The effect of replacement of cement 5%, 10% and 15% by weight with SF and RHA on compressive strength and workability has also been …


Novel Receiver For Correlated Fading Multi-Antenna Physical Network Coding Twrns, Le Chung Tran, A. Mertins, Peter James Vial, Vinh Van Nguyen 2013 University of Wollongong

Novel Receiver For Correlated Fading Multi-Antenna Physical Network Coding Twrns, Le Chung Tran, A. Mertins, Peter James Vial, Vinh Van Nguyen

Faculty of Engineering and Information Sciences - Papers: Part A

Physical Network Coding (PNC) has recently been proposed for multi-antenna Two-Way Relay Networks (TWRNs) with independent fading channels because the total network throughput could be significantly improved. However, PNC for multi-antenna TWRNs with correlated fading channels has not been considered yet. This paper thus considers an important class of multi-antenna TWRNs with the following properties: single-antenna source nodes and two-antenna relay; distance between source nodes and the relay is significantly larger than that between antennas of the relay; and channels between source nodes and the relay are correlated. For such a system, we first propose a novel correlation model that …


Power Sharing Among Multiple Solar Photovoltaic (Pv) Systems In A Radial Distribution Feeder, Brian K. Perera, Philip Ciufo 2013 University of Wollongong

Power Sharing Among Multiple Solar Photovoltaic (Pv) Systems In A Radial Distribution Feeder, Brian K. Perera, Philip Ciufo

Faculty of Engineering and Information Sciences - Papers: Part A

With an increasing penetration of solar photovoltaic (PV) systems, power distribution grids are becoming more susceptible to network voltage rise. As per applicable standards for grid-integrated PV systems, a PV system must be automatically disconnected from the grid when the terminal voltage of the PV system exceeds a defined maximum voltage. With this directive, in certain situations, PV systems connected at nodes at which the voltage sensitivity is high, may be disconnected from the grid while PV systems connected at less sensitive nodes are continuing to operate. In such a situation, owners whose PV systems are connected at nodes at …


Power Quality Emission Assessment Of Photovoltaic Inverters Based On Iec Technical Report 61000-3-15:2011, Devinda Perera, Philip Ciufo, Lasantha G. Meegahapola, Sarath Perera 2013 University of Wollongong

Power Quality Emission Assessment Of Photovoltaic Inverters Based On Iec Technical Report 61000-3-15:2011, Devinda Perera, Philip Ciufo, Lasantha G. Meegahapola, Sarath Perera

Faculty of Engineering and Information Sciences - Papers: Part A

The International Electrotechnical Committee Technical Report IEC 61000-3-15:2011 provides electromagnetic compatibility requirements and test conditions for distributed generators up to 75 A per phase. In the current research, two commercially available photovoltaic (PV) inverters up to the capacity of 3600 W were tested following the guidelines proposed in IEC 61000-3-15 in relation to low order harmonic emission and flicker emission. In addition, the harmonic and flicker emission behaviour of the PV inverters were investigated under varying irradiation conditions. Both PV inverters were observed to comply with the emission requirements prescribed by the technical report under most conditions except for even …


Identity-Based Mediated Rsa Revisited, Ibrahim Elashry, Yi Mu, Willy Susilo 2013 University of Wollongong

Identity-Based Mediated Rsa Revisited, Ibrahim Elashry, Yi Mu, Willy Susilo

Faculty of Engineering and Information Sciences - Papers: Part A

In SSYM 2001, Boneh, Ding, Tsudik and Wong presented encryption and signature schemes based on the identity-based mediated RSA (ID-MRSA), in which the users are not allowed to decrypt/sign messages without the permission of a security mediator (the SEM). This allows a simple key revocation. Subsequently, in CT-RSA 2003, Ding and Tsudik presented a security proof for these schemes. In particular, they stated that 'IB-mRSA/OAEP encryption offers equivalent the semantic security to RSA/OAEP against adaptive chosen ciphertext attacks in the random oracle model if the key generation function is division intractable'. To make the key generation function division intractable, Ding …


Capacity Deferral Credit Evaluation Of Renewable Distributed Generation, M A. Abdullah, K M. Muttaqi, A P. Agalgaonkar, D Sutanto 2013 University of Wollongong

Capacity Deferral Credit Evaluation Of Renewable Distributed Generation, M A. Abdullah, K M. Muttaqi, A P. Agalgaonkar, D Sutanto

Faculty of Engineering and Information Sciences - Papers: Part A

Renewable distributed generation (DG) units can aid in distribution network planning and can be utilized in distribution expansion planning. In order to support the development of distributed renewable resources in the distribution network and to make these resources competitive in the energy market, a well justified credit scheme needs to be devised. In this paper, an analytical method has been developed to estimate the capacity deferral credit of renewable DGs that can be claimed from distribution system operators (DSOs) due to the deferral of conventional distribution network expansion options. The distribution network adequacy has been assessed using the combined multistate …


Investigation On Slab Continuous Straightening Technology And Deformation Analysis, Xingzhong Zhang, Hongtao Zhu, Wen Huang, Baojun Shi, Anh Kiet Tieu 2013 Yanshan University

Investigation On Slab Continuous Straightening Technology And Deformation Analysis, Xingzhong Zhang, Hongtao Zhu, Wen Huang, Baojun Shi, Anh Kiet Tieu

Faculty of Engineering and Information Sciences - Papers: Part A

A new method of setting continuous bending and straightening strain rate according to temperature subzone was brought forward. By making use of the high temperature creep character effectively during the continuous casting slab being straightened, a new model curve of continuous caster was developed. And by using theoretical and finite element method the strain and strain rate of the slab under multi-point straightening and the new continuous straightening were analysed. The result shows that for continuous straightening the strain rate of the slab is constant and lower than that of the slab under multi-point straightening, and the strain varies linearly. …


Verifiable And Anonymous Encryption In Asymmetric Bilinear Maps, Hui Cui, Yi Mu, Man Ho Au 2013 University of Wollongong

Verifiable And Anonymous Encryption In Asymmetric Bilinear Maps, Hui Cui, Yi Mu, Man Ho Au

Faculty of Engineering and Information Sciences - Papers: Part A

Consider a practical scenario: an untrusted gate-way is required to verify all the incoming information en-crypted via an encryption scheme, while the sender does not want to reveal any information about the plaintext and the privileged user to the gateway. That is, the gateway distributes the information to a predefined group of users and only the privileged user can open the message. To solve this problem, we need an access control mechanism to allow certain specification of the access control policies while protecting the users' privacy. With this scenario in mind, we propose the notion of verifiable and anonymous encryption …


Threshold-Oriented Optimistic Fair Exchange, Yang Wang, Man Ho Allen Au, Joseph K. Liu, Tsz Hon Yuen, Willy Susilo 2013 University of Wollongong

Threshold-Oriented Optimistic Fair Exchange, Yang Wang, Man Ho Allen Au, Joseph K. Liu, Tsz Hon Yuen, Willy Susilo

Faculty of Engineering and Information Sciences - Papers: Part A

Fair exchange protocol aims to allow two parties to exchange digital items in a fair manner. It is well-known that fairness can only be achieved with the help of a trusted third party, usually referred to as arbitrator. A fair exchange protocol is optimistic if the arbitrator is not involved in the normal execution of the fair exchange process. That is, its presence is necessary only when one of the exchanging parties is dishonest. Traditionally, the items being exchanged are digital signatures. In this paper, we consider the items to be threshold signatures. Specifically, the signatures are created by a …


Effect Of Confining Pressure And Frequency On The Deformation Of Ballast, Pramod Kumar Thakur, Jayan Sylaja Vinod, Buddhima Indraratna 2013 University of Wollongong

Effect Of Confining Pressure And Frequency On The Deformation Of Ballast, Pramod Kumar Thakur, Jayan Sylaja Vinod, Buddhima Indraratna

Faculty of Engineering and Information Sciences - Papers: Part A

Increasing the speed and frequency of trains with the same static axle weight imparts higher dynamic axle loads more frequently. When this occurs on existing track which has not been designed for such loading there can be increased rates of ballast degradation, characterised by unacceptable deformation and lateral spread, leading to more frequent requirements for track maintenance. Recent studies carried out at the University of Wollongong highlighted that confining pressure and frequency have a significant influence on the permanent deformation and degradation of ballast. However, confinement required to keep the deformation and degradation of the ballasted track to an acceptable …


Unstable Willmore Surfaces Of Revolution Subject To Natural Boundary Conditions, Anna Dall'Acqua, Klaus Deckelnick, Glen Wheeler 2013 Otto-Von-Guericke-Universitat

Unstable Willmore Surfaces Of Revolution Subject To Natural Boundary Conditions, Anna Dall'acqua, Klaus Deckelnick, Glen Wheeler

Faculty of Engineering and Information Sciences - Papers: Part A

In the class of surfaces with fixed boundary, critical points of the Willmore functional are naturally found to be those solutions of the Euler-Lagrange equation where the mean curvature on the boundary vanishes. We consider the case of symmetric surfaces of revolution in the setting where there are two families of stable solutions given by the catenoids. In this paper we demonstrate the existence of a third family of solutions which are unstable critical points of the Willmore functional, and which spatially lie between the upper and lower families of catenoids. Our method does not require any kind of smallness …


Behaviour Of A Compacted Silty Sand Under Constant Water Content Shearing, Ana Heitor, Cholachat Rujikiatkamjorn, Buddhima Indraratna 2013 University of Wollongong

Behaviour Of A Compacted Silty Sand Under Constant Water Content Shearing, Ana Heitor, Cholachat Rujikiatkamjorn, Buddhima Indraratna

Faculty of Engineering and Information Sciences - Papers: Part A

This structure derived from compacting the soil at different water contents and energy levels can have a substantial effect on its shear strength. While the shear strength with varying suction can be estimated based on the saturated shear strength parameters and the unsaturated angle of shearing resistance (0b), limited studies have explored the variation of strength properties with different compaction states. In this paper, the shear strength of a silty sand soil was investigated using a conventional direct shear box under constant water content condition. The tests were conducted on specimens prepared by Proctor compaction with three different normal pressures. …


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