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Social and Behavioral Sciences Commons™
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Articles 1 - 7 of 7
Full-Text Articles in Social and Behavioral Sciences
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.