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Full-Text Articles in Social and Behavioral Sciences
Approximation Algorithm For Data Broadcasting In Duty Cycled Multi-Hop Wireless Networks, Dianbo Zhao, Kwan-Wu Chin
Approximation Algorithm For Data Broadcasting In Duty Cycled Multi-Hop Wireless Networks, Dianbo Zhao, Kwan-Wu Chin
Faculty of Engineering and Information Sciences - Papers: Part A
Broadcast is a fundamental operation in wireless networks. To this end, many past studies have studied the NP-hard, broadcast problem for always-on multi-hop networks. However, in wireless sensor networks, nodes are powered by batteries, meaning, they have finite energy. Consequently, nodes are required to have a low duty cycle, whereby they switch between active and sleep state periodically. This means that a transmission from a node may not reach all of its neighbors simultaneously. Consequently, any developed broadcast protocols must consider collisions and the wake-up times of neighboring nodes. Henceforth, this paper studies the minimum latency broadcast scheduling problem in …
Cost-Sensitive Cascade Graph Neural Networks, Nguyen Van Tuc, Ah Chung Tsoi, Markus Hagenbuchner
Cost-Sensitive Cascade Graph Neural Networks, Nguyen Van Tuc, Ah Chung Tsoi, Markus Hagenbuchner
Faculty of Engineering and Information Sciences - Papers: Part A
This paper introduces a novel cost sensitive weighted samples approach to a cascade of Graph Neural Networks for learning from imbalanced data in the graph structured input domain. This is shown to be very effective in addressing the effects of imbalanced data distribution on learning systems. The proposed idea is based on a weighting mechanism which forces the network to encode misclassified graphs (or nodes) more strongly. We evaluate the approach through an application to the well known Web spam detection problem, and demonstrate that the general-ization performance is improved as a result. Indeed the results obtained reported in this …
Security Analysis Of A Distributed Reprogramming Protocol For Wireless Sensor Networks, Yong Yu, Jianbing Ni, Ying Sun
Security Analysis Of A Distributed Reprogramming Protocol For Wireless Sensor Networks, Yong Yu, Jianbing Ni, Ying Sun
Faculty of Engineering and Information Sciences - Papers: Part A
Reprogramming for wireless sensor networks is essential to upload new code or to alter the functionality of existing code. To overcome the weakness of the centralized approach of the traditional solutions, He et al. proposed the notion of distributed reprogramming where multiple authorized network users are able to reprogram sensor nodes without involving the base station. They also gave a novel distributed reprogramming protocol called SDRP by using identity-based signature, and provided a comprehensive security analysis for their protocol. In this letter, unfortunately, we demonstrate that SDRP is insecure as the protocol fails to satisfy the property of authenticity and …
Facile Synthesis Of Hierarchical Networks Composed Of Highly Interconnected V2o5 Nanosheets Assembled On Carbon Nanotubes And Their Superior Lithium Storage Properties, Ruixiang Yu, Chaofeng Zhang, Qing Meng, Zhixin Chen, Hua-Kun Liu, Zaiping Guo
Facile Synthesis Of Hierarchical Networks Composed Of Highly Interconnected V2o5 Nanosheets Assembled On Carbon Nanotubes And Their Superior Lithium Storage Properties, Ruixiang Yu, Chaofeng Zhang, Qing Meng, Zhixin Chen, Hua-Kun Liu, Zaiping Guo
Faculty of Engineering and Information Sciences - Papers: Part A
Hierarchical networks with highly interconnected V2O5 nanosheets (NSs) anchored on skeletons of carbon nanotubes (CNTs) are prepared by a facile hydrothermal treatment and a following calcination for the first time. Benefiting from these unique structural features, the as-prepared CNT@V2O5 material shows dramatically excellent electrochemical performance with remarkable long cyclability (137-116 mA h g-1 after 400 cycles) at various high rates (20 C to 30 C) and very good rate capability for highly reversible lithium storage. The excellent electrochemical performance suggests its promising use as a cathode material for future lithium-ion batteries.
A Secure And Effective Anonymous User Authentication Scheme For Roaming Service In Global Mobility Networks, Fentong Wen, Willy Susilo, Guomin Yang
A Secure And Effective Anonymous User Authentication Scheme For Roaming Service In Global Mobility Networks, Fentong Wen, Willy Susilo, Guomin Yang
Faculty of Engineering and Information Sciences - Papers: Part A
In global mobility networks, anonymous user authentication is an essential task for enabling roaming service. In a recent paper, Jiang et al. proposed a smart card based anonymous user authentication scheme for roaming service in global mobility networks. This scheme can protect user privacy and is believed to have many abilities to resist a range of network attacks, even if the secret information stored in the smart card is compromised. In this paper, we analyze the security of Jiang et al.'s scheme, and show that the scheme is in fact insecure against the stolen-verifier attack and replay attack. Then, we …
On Improving Capacity And Delay In Multi Tx/Rx Wireless Mesh Networks With Weighted Links, Hung-Yi Loo, Sieteng Soh, Kwan-Wu Chin
On Improving Capacity And Delay In Multi Tx/Rx Wireless Mesh Networks With Weighted Links, Hung-Yi Loo, Sieteng Soh, Kwan-Wu Chin
Faculty of Engineering and Information Sciences - Papers: Part A
This paper considers the problem of deriving a link schedule for Time Division Multiple Access (TDMA)-based concurrent transmit/receive Wireless Mesh Networks (WMNs) that results in low end-to-end delays as well as high network capacity. We first propose a MAX-CUT heuristic approach, called Algo-2, that maximizes link activations in each slot of a super-frame. Algo-2 is shown to produce better network capacity as compared to existing heuristic approaches and significantly improves the super-frame length of an existing MAX-CUT approach that enforces 2-phase transmit-receive restriction - a node that transmits (receives) in slot i ≥ 1 is to become a receiver (transmitter) …
Approximation Algorithms For Interference Aware Broadcast In Wireless Networks, Dianbo Zhao, Kwan-Wu Chin
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 …
Comparative Analysis Of Dynamic Line Rating Models And Feasibility To Minimise Energy Losses In Wind Rich Power Networks, Mathew Simms, Lasantha Meegahapola
Comparative Analysis Of Dynamic Line Rating Models And Feasibility To Minimise Energy Losses In Wind Rich Power Networks, Mathew Simms, Lasantha Meegahapola
Faculty of Engineering and Information Sciences - Papers: Part A
Wind power generation has indicated an exponential increase during last two decades and existing transmission network infrastructure is increasingly becoming inadequate to transmit remotely generated wind power to load centres in the network. The dynamic line rating (DLR) is one of the viable solutions to improve the transmission line ampacity during high wind penetration without investing on an additional transmission network. The main objective of this study is to identify the basic differences between two main line rating standards, since transmission network service providers (TNSPs) heavily depend on these two standards when developing their line rating models. Therefore, a parameter …
Large Networks Of Vertical Multi-Layer Graphenes With Morphology-Tunable Magnetoresistance, Zengji Yue, Igor Levchenko, Shailesh Kumar, Donghan Seo, Xiaolin Wang, S X. Dou, Kostya Ken Ostrikov
Large Networks Of Vertical Multi-Layer Graphenes With Morphology-Tunable Magnetoresistance, Zengji Yue, Igor Levchenko, Shailesh Kumar, Donghan Seo, Xiaolin Wang, S X. Dou, Kostya Ken Ostrikov
Faculty of Engineering and Information Sciences - Papers: Part A
We report on the comparative study of magnetotransport properties of large-area vertical few-layer graphene networks with different morphologies, measured in a strong (up to 10 T) magnetic field over a wide temperature range. The petal-like and tree-like graphene networks grown by a plasma enhanced CVD process on a thin (500 nm) silicon oxide layer supported by a silicon wafer demonstrate a significant difference in the resistance-magnetic field dependencies at temperatures ranging from 2 to 200 K. This behaviour is explained in terms of the effect of electron scattering at ultra-long reactive edges and ultra-dense boundaries of the graphene nanowalls. Our …
Exponential-Family Random Graph Models For Valued Networks, Pavel N. Krivitsky
Exponential-Family Random Graph Models For Valued Networks, Pavel N. Krivitsky
Faculty of Engineering and Information Sciences - Papers: Part A
Exponential-family random graph models (ERGMs) provide a principled and flexible way to model and simulate features common in social networks, such as propensities for homophily, mutuality, and friend-of-a- friend triad closure, through choice of model terms (sufficient statistics). However, those ERGMs modeling the more complex features have, to date, been limited to binary data: presence or absence of ties. Thus, analysis of valued networks, such as those where counts, measurements, or ranks are observed, has necessitated dichotomizing them, losing information and introducing biases. In this work, we generalize ERGMs to valued networks. Focusing on modeling counts, we formulate an ERGM …
Comparison Of Methodologies For Assessment Of Harmonic Current Emission Limits For Large Installations Connected To Lv Networks, Biyanvilage Perera, Sarath Perera, Philip Ciufo, Victor J. Gosbell
Comparison Of Methodologies For Assessment Of Harmonic Current Emission Limits For Large Installations Connected To Lv Networks, Biyanvilage Perera, Sarath Perera, Philip Ciufo, Victor J. Gosbell
Faculty of Engineering and Information Sciences - Papers: Part A
With the proliferation of large, disturbing installations (loads and distribution generators) connected to public low voltage networks, managing the harmonic voltage levels in the network has become a key concern to distribution network service providers (DNSPs). Therefore, it is important that DNSPs limit the harmonic current emission by individual installations. This paper reviews a number of methodologies that exist in the current technical literature in relation to the assessment of harmonic current emission limits for disturbing installations connected to the public LV network. Application of these methodologies is demonstrated through a case study on a test network. The study shows …
Power-Aware Routing In Networks With Delay And Link Utilization Constraints, Gongqi Lin, Sieteng Soh, Mihai Lazarescu, Kwan-Wu Chin
Power-Aware Routing In Networks With Delay And Link Utilization Constraints, Gongqi Lin, Sieteng Soh, Mihai Lazarescu, Kwan-Wu Chin
Faculty of Engineering and Information Sciences - Papers: Part A
Current network infrastructures are over-provisioned and thus exhibit poor power efficiency at low traffic load. In this paper, we consider networks comprising of bundled links, whereby each link has one or more physical cables that can be switched off independently. The problem at hand is then to switch off redundant cables during off peak periods, while retaining the QoS provided to existing traffic demands. Unfortunately, the problem to maximally shutdown redundant cables is an NP-complete problem. Henceforth, we design a fast heuristic, called Multiple Paths by Shortest Path First (MSPF), that aims to maximize the number of switched-off cables subject …
Impact Of Wind Generator Control Strategies On Flicker Emission In Distribution Networks, Lasantha Meegahapola, Sarath Perera
Impact Of Wind Generator Control Strategies On Flicker Emission In Distribution Networks, Lasantha Meegahapola, Sarath Perera
Faculty of Engineering and Information Sciences - Papers: Part A
Renewable power generators are increasingly being integrated to electricity networks to achieve future renewable energy targets in power generation. In particular, wind power generation has already reported substantial penetration levels in electricity networks. Traditionally, flicker phenomenon is considered to be one of the power quality issues in power distribution networks due to fluctuating consumer loads connected to the network. Large-scale integration of wind power generators may create significant voltage fluctuations in distribution feeders due to stochastic and intermittent nature of the wind resources. This study aims to investigate and characterize the flicker emission under different control strategies for DFIG based …
Performance Analysis Of Distribution Networks Under High Penetration Of Solar Pv, M J. E Alam, Kashem M. Muttaqi, Darmawan Sutanto, L Elder, A Baitch
Performance Analysis Of Distribution Networks Under High Penetration Of Solar Pv, M J. E Alam, Kashem M. Muttaqi, Darmawan Sutanto, L Elder, A Baitch
Faculty of Engineering and Information Sciences - Papers: Part A
Integration of solar photovoltaic (PV) resources into distribution networks changes the normally expected network behaviour by injecting real power into the point of connection. Depending on the characteristics and setup of the PV inverter, reactive power could also be injected into the network. The impact will depend on the control strategy adopted for reactive power injection. Typically, solar PV units are installed at low voltage (LV) level in distribution networks. Cluster based installation of numerous PV inverters in the LV level will impact the operation of both the host LV network and the upstream medium voltage network. With random variations …
Flicker Propagation Analysis In Distribution Networks With Embedded Generation, D Perera, L Meegahapola, S Perera, P Ciufo
Flicker Propagation Analysis In Distribution Networks With Embedded Generation, D Perera, L Meegahapola, S Perera, P Ciufo
Faculty of Engineering and Information Sciences - Papers: Part A
Embedded generators such as wind generators can produce observable voltage fluctuations during variable wind conditions hence flicker. The flicker produced by such intermittent and fluctuating generating sources can propagate to other parts of the distribution network while creating power quality issues in distribution feeders. This study presents a flicker emission analysis for a doubly-fed induction generator (DFIG) based wind farm and investigate the pertinent factors which influence flicker propagation and attenuation in distribution feeders. Study has shown that voltage fluctuations are significantly influenced by the attenuation characteristics of various load types (i.e. constant power, impedance and current loads) connected to …
Hybrid Power Saving Technique For Wireless Sensor Networks, Asama Alshaibi, Peter Vial, Montserrat Ros
Hybrid Power Saving Technique For Wireless Sensor Networks, Asama Alshaibi, Peter Vial, Montserrat Ros
Faculty of Engineering and Information Sciences - Papers: Part A
In wireless communication, idle listening, receiving and transmitting are the main source of consumption of energy. This paper gives an overview of several techniques used for wireless networks. We incorporated PSM and PC to gain the advantage of PSM (reduce idle listening) and PC (reduce receiving and transmitting power) and implemented them in the IEEE 802.15.4 protocol. The results show that the new hybrid technique saves more power than PSM and PC individually. © 2012 IEEE.
Network Neighbor Effects On Customer Churn In Cell Phone Networks, Pavel N. Krivitsky, Pedro Ferreira, Rahul Telang
Network Neighbor Effects On Customer Churn In Cell Phone Networks, Pavel N. Krivitsky, Pedro Ferreira, Rahul Telang
Faculty of Engineering and Information Sciences - Papers: Part A
No abstract provided.
A Reduced Reference Image Quality Metric Based On Feature Fusion And Neural Networks, Aladine Chetouani, Azeddine Beghdadi, Mohamed Deriche, Abdesselam Bouzerdoum
A Reduced Reference Image Quality Metric Based On Feature Fusion And Neural Networks, Aladine Chetouani, Azeddine Beghdadi, Mohamed Deriche, Abdesselam Bouzerdoum
Faculty of Engineering and Information Sciences - Papers: Part A
A Global Reduced Reference Image Quality Metric (IQM) based on feature fusion using neural networks is proposed. The main idea is the introduction of a Reduced Reference degradation-dependent IQM (RRIQM/D) across a set of common distortions. The first stage consists of extracting a set of features from the wavelet-based edge map. Such features are then used to identify the type of degradation using Linear Discriminant Analysis (LDA). The second stage consists of fusing the extracted features into a single measure using Artificial Neural Networks (ANN). The result is a degradation- dependent IQM measure called the RRIQM/D. The performance of the …
Hierarchical Anatomical Brain Networks For Mci Prediction: Revisiting Volumetric Measures, Luping Zhou, Yaping Wang, Yang Li, Pew-Thian Yap, Dinggang Shen, Alzheimers Disease Neuroimaging Initiative (Adni)
Hierarchical Anatomical Brain Networks For Mci Prediction: Revisiting Volumetric Measures, Luping Zhou, Yaping Wang, Yang Li, Pew-Thian Yap, Dinggang Shen, Alzheimers Disease Neuroimaging Initiative (Adni)
Faculty of Engineering and Information Sciences - Papers: Part A
Owning to its clinical accessibility, T1-weighted MRI (Magnetic Resonance Imaging) has been extensively studied in the past decades for prediction of Alzheimer's disease (AD) and mild cognitive impairment (MCI). The volumes of gray matter (GM), white matter (WM) and cerebrospinal fluid (CSF) are the most commonly used measurements, resulting in many successful applications. It has been widely observed that disease-induced structural changes may not occur at isolated spots, but in several inter-related regions. Therefore, for better characterization of brain pathology, we propose in this paper a means to extract inter-regional correlation based features from local volumetric measurements. Specifically, our approach …
Hierarchical Anatomical Brain Networks For Mci Prediction By Partial Least Square Analysis, Luping Zhou, Yaping Wang, Yang Li, Pew-Thian Yap, Dinggang Shen
Hierarchical Anatomical Brain Networks For Mci Prediction By Partial Least Square Analysis, Luping Zhou, Yaping Wang, Yang Li, Pew-Thian Yap, Dinggang Shen
Faculty of Engineering and Information Sciences - Papers: Part A
Owning to its clinical accessibility, T1-weighted MRI has been extensively studied for the prediction of mild cognitive impairment (MCI) and Alzheimer's disease (AD). The tissue volumes of GM, WM and CSF are the most commonly used measures for MCI and AD prediction. We note that disease-induced structural changes may not happen at isolated spots, but in several inter-related regions. Therefore, in this paper we propose to directly extract the inter-region connectivity based features for MCI prediction. This involves constructing a brain network for each subject, with each node representing an ROI and each edge representing regional interactions. This network is …
Methods For Generating Complex Networks With Selected Structural Properties For Simulations: A Review And Tutorial For Neuroscientists, Brenton Prettejohn, Matthew Berryman, Mark Mcdonnell
Methods For Generating Complex Networks With Selected Structural Properties For Simulations: A Review And Tutorial For Neuroscientists, Brenton Prettejohn, Matthew Berryman, Mark Mcdonnell
Faculty of Engineering and Information Sciences - Papers: Part A
Many simulations of networks in computational neuroscience assume completely homogenous random networks of the Erdös–Rényi type, or regular networks, despite it being recognized for some time that anatomical brain networks are more complex in their connectivity and can, for example, exhibit the “scale-free” and “small-world” properties. We review the most well known algorithms for constructing networks with given non-homogeneous statistical properties and provide simple pseudo-code for reproducing such networks in software simulations. We also review some useful mathematical results and approximations associated with the statistics that describe these network models, including degree distribution, average path length, and clustering coefficient. We …
Knowledge Sharing Through Virtual Layers In Regional Sustainable Development Networks, Rosemary A. Van Der Meer, Luba Torlina, Jamie Mustard
Knowledge Sharing Through Virtual Layers In Regional Sustainable Development Networks, Rosemary A. Van Der Meer, Luba Torlina, Jamie Mustard
Faculty of Engineering and Information Sciences - Papers: Part A
Our research examines how the organisational structure facilitates knowledge sharing within the group. This case study examines a Victorian regional sustainable group using interviews and social network analysis to identify the group's organisational structure and its effect on knowledge sharing between the members. Our findings indicate that while the mixed membership, lack of hierarchy and layered structure are complex, these elements work together to provide members with a rich body of knowledge. The diversity and differences in membership are complimentary and combined can provide a more in-depth understanding of the regional sustainable development issues.
Fitting Position Latent Cluster Models For Social Networks With Latentnet, Pavel N. Krivitsky, M Handcock
Fitting Position Latent Cluster Models For Social Networks With Latentnet, Pavel N. Krivitsky, M Handcock
Faculty of Engineering and Information Sciences - Papers: Part A
latentnet is a package to fit and evaluate statistical latent position and cluster models for networks. Hoff, Raftery, and Handcock (2002) suggested an approach to modeling networks based on positing the existence of an latent space of characteristics of the actors. Relationships form as a function of distances between these characteristics as well as functions of observed dyadic level covariates. In latentnet social distances are represented in a Euclidean space. It also includes a variant of the extension of the latent position model to allow for clustering of the positions developed in Handcock, Raftery, and Tantrum (2007). The package implements …
A Review Of Routing Protocols For Mobile Ad Hoc Networks, Mehran Abolhasan, Tadeusz Wysocki, Eryk Dutkiewicz
A Review Of Routing Protocols For Mobile Ad Hoc Networks, Mehran Abolhasan, Tadeusz Wysocki, Eryk Dutkiewicz
Faculty of Engineering and Information Sciences - Papers: Part A
The 1990s have seen a rapid growth of research interests in mobile ad hoc networking. The infrastructureless and the dynamic nature of these networks demands new set of networking strategies to be implemented in order to provide efficient end-to-end communication. This, along with the diverse application of these networks in many different scenarios such as battlefield and disaster recovery, have seen MANETs being researched by many different organisations and institutes. MANETs employ the traditional TCP/IP structure to provide end-to-end communication between nodes. However, due to their mobility and the limited resource in wireless networks, each layer in the TCP/IP model …
Network Reconfiguration For Enhancement Of Voltage Stability In Distribution Networks, Kashem M. Muttaqi, Velappa Ganapathy, G G. Jasmon
Network Reconfiguration For Enhancement Of Voltage Stability In Distribution Networks, Kashem M. Muttaqi, Velappa Ganapathy, G G. Jasmon
Faculty of Engineering and Information Sciences - Papers: Part A
Network reconfiguration is performed by altering the topological structure of distribution feeders. By reconfiguring the network, voltage stability can be maximised for a particular set of loads in distribution systems. A new algorithm is formulated for enhancement of voltage stability by network reconfiguration. Initially, a certain number of switching combinations is generated using the combination of tie and its two neighbouring switches, and the best combination of switches for maximising the voltage stability in the network among them is determined. Then the search is extended by considering the branches next to the open-branches of the best configuration one by one …
A Geometric Approach For Three-Phase Load Balancing In Distribution Networks, Kashem M. Muttaqi, Velappa Ganapathy, G B. Jasmon
A Geometric Approach For Three-Phase Load Balancing In Distribution Networks, Kashem M. Muttaqi, Velappa Ganapathy, G B. Jasmon
Faculty of Engineering and Information Sciences - Papers: Part A
No abstract provided.
A Novel Method For Loss Minimization In Distribution Networks, Kashem M. Muttaqi, Velappa Ganapathy, G B. Jasmon, M Buhari
A Novel Method For Loss Minimization In Distribution Networks, Kashem M. Muttaqi, Velappa Ganapathy, G B. Jasmon, M Buhari
Faculty of Engineering and Information Sciences - Papers: Part A
Network reconfiguration for loss minimization is the determination of switching-options that minimizes the power losses for a particular set of loads on a distribution system. In this paper, a novel method is proposed by formulating an algorithm to reconfigure distribution networks for loss minimization. An efficient technique is used to determine the switching combinations, select the status of the switches, and find the best combination of switches for minimum loss. In the first stage of the proposed algorithm, a limited number of switching combinations is generated and the best switching combination is determined. In the second stage, an extensive search …
Network Reconfiguration For Load Balancing In Distribution Networks, Kashem M. Muttaqi, Velappa Ganapathy, G G. Jasmon
Network Reconfiguration For Load Balancing In Distribution Networks, Kashem M. Muttaqi, Velappa Ganapathy, G G. Jasmon
Faculty of Engineering and Information Sciences - Papers: Part A
Network reconfiguration of a power distribution system is an operation to alter the topological structure of distribution feeders by changing opedclosed status of sectionalising and tie switches. By transferring loads from the heavily loaded feeders to the lightly loaded ones, network reconfiguration can balance feeder loads and alleviate overload conditions of a network. The branch load-balancing index and the overall system load-balancing index are used to determine the loading conditions of the system and maximum system loading capacity. The index value has to be minimum in the optimal configuration of load balancing. For optimal load balancing condition the branch load-balancing …