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Full-Text Articles in Physical Sciences and Mathematics

An Automated Land Subdivision Tool For Urban And Regional Planning: Concepts, Implementation And Testing, Rohan Wickramasuriya, Laurie A. Chisholm, Marjetta Puotinen, Nicholas Gill, Peter Klepeis Sep 2013

An Automated Land Subdivision Tool For Urban And Regional Planning: Concepts, Implementation And Testing, Rohan Wickramasuriya, Laurie A. Chisholm, Marjetta Puotinen, Nicholas Gill, Peter Klepeis

Rohan Wickramasuriya, Ph.D.

Simulation of the land subdivision process is useful in many applied and research areas. Planners use such tools to understand potential impacts of planning regulations prior to their implementation. While the credibility of both land-use change and urban growth models would be enhanced by integrating capabilities to simulate land subdivision, such research is lacking in the published literature. Of the few subdivision tools that exist, most are either not fully-automated or are unable to generate realistic subdivision layouts. This limits their applicability, particularly for high resolution land-use change models. In this paper, we present a fully-automated land subdivision tool that …


A Scalable Lightweight Distributed Crawler For Crawling With Limited Resources, Milly W. Kc, Markus Hagenbuchner, Ah Chung Tsoi Jul 2013

A Scalable Lightweight Distributed Crawler For Crawling With Limited Resources, Milly W. Kc, Markus Hagenbuchner, Ah Chung Tsoi

Ah Chung Tsoi

Web page crawlers are an essential component in a number of Web applications. The sheer size of the Internet can pose problems in the design of Web crawlers. All currently known crawlers implement approximations or have limitations so as to maximize the throughput of the crawl, and hence, maximize the number of pages that can be retrieved within a given time frame. This paper proposes a distributed crawling concept which is designed to avoid approximations, to limit the network overhead, and to run on relatively inexpensive hardware. A set of experiments, and comparisons highlight the effectiveness of the proposed approach.


Aeolian-Fluvial Interaction: Evidence For Late Quaternary Channel Change And Wind-Rift Linear Dune Formation In The Northwestern Simpson Desert, Australia, Gerald C. Nanson, Brian G. Jones, David M. Price, Tim Pietsch, C Bristow, Cameron B. Hollands Jun 2013

Aeolian-Fluvial Interaction: Evidence For Late Quaternary Channel Change And Wind-Rift Linear Dune Formation In The Northwestern Simpson Desert, Australia, Gerald C. Nanson, Brian G. Jones, David M. Price, Tim Pietsch, C Bristow, Cameron B. Hollands

B. G. Jones

In central Australia the most easterly extent of the MacDonnell Ranges borders the northwestern Simpson Desert where widely spaced strike ridges intercept the regional linear dunefield. Topographic basins have disrupted regional drainage lines and isolated dune sets from the main dunefield. In the western part of Camel Flat basin large, red coloured linear dunes of fine sand, ~ 74 ka and older, are oriented almost due north. Through gaps in the ranges the Todd River traversed the eastern part of the basin until ~25 ka when it apparently avulsed ~25 km eastwards to its present position. Subsequently, linear dunes, smaller, …


A Spectral-Collocation Method For Pricing Perpetual American Puts With Stochastic Volatility, Song-Ping Zhu, Wenting Chen Jun 2013

A Spectral-Collocation Method For Pricing Perpetual American Puts With Stochastic Volatility, Song-Ping Zhu, Wenting Chen

Professor Song-Ping Zhu

Based on the Legendre pseudospectral method, we propose a numerical treatment for pricing perpetual American put option with stochastic volatility. In this simple approach, a nonlinear algebraic equation system is first derived, and then solved by the Gauss–Newton algorithm. The convergence of the current scheme is ensured by constructing a test example similar to the original problem, and comparing the numerical option prices with those produced by the classical Projected SOR (PSOR) method. The results of our numerical experiments suggest that the proposed scheme is both accurate and efficient, since the spectral accuracy can be easily achieved within a small …


A Numerical Model For Multiphase Flow Based On The Gmpps Formulation, Part I Kinematics, Song-Ping Zhu, Frank Bierbrauer Jun 2013

A Numerical Model For Multiphase Flow Based On The Gmpps Formulation, Part I Kinematics, Song-Ping Zhu, Frank Bierbrauer

Professor Song-Ping Zhu

The CFD modeling of two dimensional multiphase ows is a useful tool in industry, although accurate modeling itself remains a difficult task. One of the difficulties is to track the complicated topological deformations of the interfaces between di erent phases. This paper describes a marker-particle method designed to track fluid interfaces for fluid ows of at least three phases. The interface-tracking scheme presented in this paper is the first part of a series of papers presenting our complete model based on a one-field Godunov marker-particle projection scheme (GMPPS). In this part, we shall focus on the presentation of the interface-tracking …


System Architecture And Mobility Management For Mobile Immersive Communications, Mehran Dowlatshahi, Farzad Safaei Jun 2013

System Architecture And Mobility Management For Mobile Immersive Communications, Mehran Dowlatshahi, Farzad Safaei

Professor Farzad Safaei

We propose a system design for delivery of immersive communications to mobile wireless devices based on a distributed proxy model. It is demonstrated that this architecture addresses key technical challenges for the delivery of these services, that is, constraints on link capacity and power consumption in mobile devices. However, additional complexity is introduced with respect to application layer mobility management. The paper proposes three possible methods for updating proxy assignments in response to mobility management and compares the performance of these methods.


Distributing Network Game Servers For Improved Geographical Scalability, Paul A. Boustead, Farzad Safaei, Jeremy Brun Jun 2013

Distributing Network Game Servers For Improved Geographical Scalability, Paul A. Boustead, Farzad Safaei, Jeremy Brun

Professor Farzad Safaei

World-wide multiplayer games present several scalability challenges for large-scale deployment. In recent years, significant research has been devoted to scaling in terms of number of players so that the same virtual world can accommodate larger number of simultaneous avatars. A possible solution is to use grid computing techniques for distribution of processing over a cluster or a distributed set of servers. Scalability with respect to geographical distribution of players is another challenge. Large geographical distances between players introduces propagation delays which are impossible to avoid. Without proper design, responsiveness of the application to user inputs is degraded even when there …


Facial Expression Recognition For Multiplayer Online Games, Ce Zhan, Wanqing Li, Philip O. Ogunbona, Farzad Safaei Jun 2013

Facial Expression Recognition For Multiplayer Online Games, Ce Zhan, Wanqing Li, Philip O. Ogunbona, Farzad Safaei

Professor Farzad Safaei

The Multiplayer Online Game (MOG) becomes more popular than any other types of computer games for its collaboration, communication and interaction ability. However, compared with the ordinary human communication, the MOG still has many limitations, especially in communication using facial expressions. Although detailed facial animation has already been achieved in a number of MOGs, players have to use text commands to control avatars expressions. In this paper, we briefly review the state of the art in facial expression recognition and propose an automatic expression recognition system that can be integrated into a MOG to control the avatar’s facial expressions. We …


Synthesis And Optimization Of Fluorine-Free Y And Cu Precursor Solution For Mod Processing Of Ybco Coated Conductor, Jaimoo Yoo, Young-Kuk Kim, Kookchae Chung, Jaewoong Ko, Xiaolin Wang, S X. Dou Jun 2013

Synthesis And Optimization Of Fluorine-Free Y And Cu Precursor Solution For Mod Processing Of Ybco Coated Conductor, Jaimoo Yoo, Young-Kuk Kim, Kookchae Chung, Jaewoong Ko, Xiaolin Wang, S X. Dou

Shi Xue Dou

MOD solutions for YBCO coated conductors were synthesized with fluorine-free Y & Cu precursor. The fluorine content in the precursor solution was significantly reduced and a fast calcination profile was realized. A crack-free & thick precursor film was successfully obtained just after less than 2 hours of calcination in wet O2 atmosphere. Optimization of the precursor solution with Sm addition enables further improvement of thickness and uniformity of precursor films. The calcinated precursor film was successfully converted to dense and uniform YBCO film after annealing in wet Ar/O2 atmosphere. The measured critical current value was about 273 A/cm-w (Jc ~ …


A Study On The Charge-Discharge Mechanism Of Co3o4 As An Anode For The Li Ion Secondary Battery, Yong-Mook Kang, Min-Sang Song, Jin-Ho Kim, Hyun-Seok Kim, Min-Sik Park, Jai-Young Lee, Hua-Kun Liu, S X. Dou Jun 2013

A Study On The Charge-Discharge Mechanism Of Co3o4 As An Anode For The Li Ion Secondary Battery, Yong-Mook Kang, Min-Sang Song, Jin-Ho Kim, Hyun-Seok Kim, Min-Sik Park, Jai-Young Lee, Hua-Kun Liu, S X. Dou

Shi Xue Dou

Co3O4 has shown acceptable electrochemical properties as the anode material of Li secondary batteries. In detail, its capacity reached about 700 mAh/g, twice as high as graphite, and 93.4% of initial capacity was retained after 100 cycles. EIS (electrochemical impedance spectroscopy) analyses revealed that after the 1st cycle, the insertion or extraction of Li ions in Co3O4 can occur homogeneously and reversibly (randless-like behavior, homogeneous mixture: Co + Li2O (in the state of Li insertion), Co3O4 (in the state of Li extraction)). In fact, the coulombic efficiency of Co3O4 was almost 100% except for the 1st cycle. According to P. …


Silicon Oil: A Cheap Liquid Additive For Enhancing In-Field Critical Current Density In Mgb2, Xiaolin Wang, Zhenxiang Cheng, S X. Dou Jun 2013

Silicon Oil: A Cheap Liquid Additive For Enhancing In-Field Critical Current Density In Mgb2, Xiaolin Wang, Zhenxiang Cheng, S X. Dou

Shi Xue Dou

In this work, the authors report on significant flux pinning enhancement in MgB2 that has been easily obtained using a liquid additive, silicon oil. MgB2 bulk samples with 0 up to 30 wt % silicon oil added were prepared by an in situ reaction. Results showed that the Si and C released from the decomposition of the silicon oil formed Mg2Si and substituted into B sites, respectively. Increasing the amount of the Si oil up to 15 wt % has resulted in the reduction of the lattice parameters, as well as Tc and R(300 K)/R(Tc) values, accompanied by a significant …


Flux-Pinning Mechanism In Silicone-Oil Doped Mgb2: Evidence For Charge-Carrier Mean Free Path Fluctuation Pinning, Shaban R. Ghorbani, Xiaolin Wang, S X. Dou, Sung-Ik Lee, Md S. Hossain Jun 2013

Flux-Pinning Mechanism In Silicone-Oil Doped Mgb2: Evidence For Charge-Carrier Mean Free Path Fluctuation Pinning, Shaban R. Ghorbani, Xiaolin Wang, S X. Dou, Sung-Ik Lee, Md S. Hossain

Shi Xue Dou

Flux-pinning mechanism of MgB2 doped with 10 wt % silicone-oil sintered at low and high temperatures has been investigated by magnetic measurements. The field dependence of the critical current density, jc(B), was analysed within the collective pinning model. A crossover field, Bsb, from the single vortex to the small vortex bundle-pinning regime was observed. For both types of sintered samples, the temperature dependence of Bsb(T) at low temperature is in good agreement with the δl pinning mechanism, i.e., pinning associated with charge-carrier mean free path fluctuation. At temperatures close to the critical temperature, however, there is evidence for δTc pinning, …


Identification Of Human Plasma Proteins As Major Clients For The Extracellular Chaperone Clusterin, Amy R. Wyatt, Mark R. Wilson May 2013

Identification Of Human Plasma Proteins As Major Clients For The Extracellular Chaperone Clusterin, Amy R. Wyatt, Mark R. Wilson

Mark R Wilson

Clusterin (CLU) is an extracellular chaperone that is likely to play an important role in protein folding quality control. This study identified three deposition disease-associated proteins as major plasma clients for clusterin by studying CLU-client complexes formed in response to physiologically relevant stress (shear stress, similar to 36 dynes/cm(2) at 37 degrees C). Analysis of plasma samples by size exclusion chromatography indicated that (i) relative to control plasma, stressed plasma contained proportionally more soluble protein species of high molecular weight, and (ii) high molecular weight species were far more abundant when proteins purified by anti-CLU immunoaffinity chromatography from stressed plasma …


Illuminating Southeast Asian Prehistory : New Archaeological And Paleoanthropological Frontiers For Luminescence Dating, Richard G. Roberts, Michael J. Morwood, Kira E. Westaway Mar 2013

Illuminating Southeast Asian Prehistory : New Archaeological And Paleoanthropological Frontiers For Luminescence Dating, Richard G. Roberts, Michael J. Morwood, Kira E. Westaway

Richard G Roberts

Since the explorations of Alfred Russel Wallace and Eugène Dubois in the nineteenth century, Southeast Asia has been one of the world's focal points for studies of biogeography and biodiversity, human evolution and dispersal, environmental change, and the spread of culture, farming, and language. Yet despite its prominence, reliable chronologies are not available for many of the critical archaeological, evolutionary, and environmental turning points that have taken place in the region during the last 1.5 million years. In this paper, we discuss some of these chronological problems and describe how luminescence dating may help overcome them. "Luminescence dating" is a …


A Mathematical Model For The Biological Treatment Of Industrial Wastewaters In A Cascade Of Four Reactors, Annette L. Worthy, Mark I. Nelson, Rubayyi Turki Alqahtani Dec 2012

A Mathematical Model For The Biological Treatment Of Industrial Wastewaters In A Cascade Of Four Reactors, Annette L. Worthy, Mark I. Nelson, Rubayyi Turki Alqahtani

Associate Professor Annette Worthy

Many industrial processes, particularly in the food industry, produce slurriesor wastewaters containing high concentrations of biodegradable organicmaterials. Before these contaminated wastewaters can be dischargedthe concentration of these pollutants must be reduced. A method which has beenextensively employed to remove biodegradable organic matter is biologicaltreatment. In this process the wastewater (or slurry) is passed through abioreactor containing biomass which grows through consumption of thepollutants.The industrial treatment of wastewaters typically employs a reactor cascade.In a reactor cascade of n reactors the effluent stream from the ith reactor inthe cascade acts as the feed stream for the (i+1)th reactor, i.e. the nextreactor. The …


Data Security And Information Privacy For Pda Accessible Clinical-Log For Medical Education In Problem-Based Learning (Pbl) Approach, Rattiporn Luanrattana, Khin Than Win, John A. Fulcher Dec 2012

Data Security And Information Privacy For Pda Accessible Clinical-Log For Medical Education In Problem-Based Learning (Pbl) Approach, Rattiporn Luanrattana, Khin Than Win, John A. Fulcher

Dr Khin Win

Data security and information privacy are the important aspects to consider for the use of mobile technology for recording clinical experience and encounter in medical education. Objective: This study aims to address the qualitative findings of the appropriate data security and information privacy for PDA accessible clinical-log in problem-based learning (PBL) approach in medical education. Method: The semi-structured interviews were conducted with the medical faculty members, honorary clinical academics and medical education technology specialists. Results: Data security and information access plan were determined for managing clinical-log data. The results directed the guideline for the future development and implementation of clinical-log …


Strategies For Implementing A Converged Ict Regulator In Indonesia, Yudhistra Nughara, William Tibben Dec 2012

Strategies For Implementing A Converged Ict Regulator In Indonesia, Yudhistra Nughara, William Tibben

Dr William Tibben

This paper draws on a six month study that aimed to broadly clarify strategies for the IndonesianGovernment to address the issue of convergence. This paper reports on one aspect of this study thatmaps stakeholder policymaker opinions about a future converged regulator in Indonesia.Convergence refers to a trend in regulation that seeks to define a single regulatory structure fortelecommunications, broadcasting and information technology. In particular, the specific aims ofthis study were to examine regulatory structures with regard to two parameters derived from theInternational Telecommunications Union (ITU): the level of independence, and institutional design.Using benchmarking as a method, three case studies of …


Understanding The Conducting States Of Active And Passive Switches In An Inverter Circuit Used For Power System Applications, Danny Sutanto, B.P. Divakar, K.W.E. Cheng Dec 2012

Understanding The Conducting States Of Active And Passive Switches In An Inverter Circuit Used For Power System Applications, Danny Sutanto, B.P. Divakar, K.W.E. Cheng

Professor Darmawan Sutanto

Bi-directional inverter circuits are commonly used in many applications in power systems, such as in FACTS devices, energy storage systems and active power filters. Many power engineering students however find it difficult to understand the conducting states of the active switches (transistors, IGBTs) and the passive switches (the antiparallel diodes connected across the active switches). It seems a mystery to them that power can flow from a lower voltage ac system to a higher voltage dc system to charge the energy storage system. This paper proposes a simple chart that intuitively explains how to determine the states (either conducting or …


Finding Distinctive Facial Areas For Face Recognition, Ce Zhan, Wanqing Li, Philip O. Ogunbona Dec 2012

Finding Distinctive Facial Areas For Face Recognition, Ce Zhan, Wanqing Li, Philip O. Ogunbona

Associate Professor Wanqing Li

One of the key issues for local appearance based face recognition methods is that how to find the most discriminative facial areas. Most of the existing methods take the assumption that anatomical facial components, such as the eyes, nose, and mouth, are the most useful areas for recognition. Other more elaborate methods locate the most salient parts within the face according to a pre-specified criterion. In this paper, a novel method is proposed to identify the discriminative facial areas for face recognition. Unlike the existing methods that only analyze the given face, the proposed method identifies the distinctive areas of …


On The Combination Of Local Texture And Global Structure For Food Classification, Zhimin Zong, Duc Thanh Nguyen, Philip O. Ogunbona, Wanqing Li Dec 2012

On The Combination Of Local Texture And Global Structure For Food Classification, Zhimin Zong, Duc Thanh Nguyen, Philip O. Ogunbona, Wanqing Li

Associate Professor Wanqing Li

This paper proposes a food image classification method using local textural patterns and their global structure to describe the food image. In this paper, a visual codebook of local textural patterns is created by employing Scale Invariant Feature Transformation (SIFT) interest point detector with the Local Binary Pattern (LBP) feature. In addition to describing the food image using local texture, the global structure of the food object is represented as the spatial distribution of the local textural structures and encoded using shape context. We evaluated the proposed method on the Pittsburgh Fast-Food Image (PFI) dataset. Experimental results showed that the …


Facial Expression Recognition For Multiplayer Online Games, Ce Zhan, Wanqing Li, Philip O. Ogunbona, Farzad Safaei Dec 2012

Facial Expression Recognition For Multiplayer Online Games, Ce Zhan, Wanqing Li, Philip O. Ogunbona, Farzad Safaei

Associate Professor Wanqing Li

The Multiplayer Online Game (MOG) becomes more popular than any other types of computer games for its collaboration, communication and interaction ability. However, compared with the ordinary human communication, the MOG still has many limitations, especially in communication using facial expressions. Although detailed facial animation has already been achieved in a number of MOGs, players have to use text commands to control avatars expressions. In this paper, we briefly review the state of the art in facial expression recognition and propose an automatic expression recognition system that can be integrated into a MOG to control the avatar’s facial expressions. We …


Dynamic Modelling Of Hydroelectric Turbine-Generator Unit Connected To A Hvdc System For Small Signal Stability Analysis, Yin Chin Choo, Ashish P. Agalgaonkar, Kashem Muttaqi, Sarath Perera, Michael Negnevitsky Dec 2012

Dynamic Modelling Of Hydroelectric Turbine-Generator Unit Connected To A Hvdc System For Small Signal Stability Analysis, Yin Chin Choo, Ashish P. Agalgaonkar, Kashem Muttaqi, Sarath Perera, Michael Negnevitsky

Dr Ashish Agalgaonkar

This paper presents the linearised small-signal dynamic modelling of hydroelectric turbine-generator (TG) unit with CIGRE first high-voltage direct current (HVDC) benchmark system in the synchronously rotating D-Q reference frame for small-signal stability analysis. The interaction behaviour between the hydroelectric unit and the dynamics and control of HVDC system is investigated utilising eigen-analysis,participation factor analysis and by conducting sensitivity studies. The computation of eigenvalues and eigenvectors for small signal stability analysis provides an invaluable insight onto the power system dynamic behaviour by characterising the damping and frequency of the system oscillatory modes. Theconsequences of different operating conditions, such as active and …


Optimisation Of Distributed Generation Units And Shunt Capacitors For Economic Operation Of Distribution Systems, Kai Zou, Sarath Perera, Kashem Muttaqi, Ashish P. Agalgaonkar Dec 2012

Optimisation Of Distributed Generation Units And Shunt Capacitors For Economic Operation Of Distribution Systems, Kai Zou, Sarath Perera, Kashem Muttaqi, Ashish P. Agalgaonkar

Dr Ashish Agalgaonkar

The integration of Distributed Generation (DG) units and shunt capacitors can be considered as an alternative approach for distribution system expansion planning not only to improve power supply quality and reliability, but also to defer major system updates. In this paper, the techno-economic issues of distribution system expansion planning with optimal sizing and siting of DG units and shunt capacitors are addressed. The minimisation of overall investment cost with the integration of DG units and shunt capacitors is assessed with the consideration of supply quality, reliability and energy loss. A new planning methodology by using Particle Swarm Optimisation (PSO) is …


Pbtrust: A Priority-Based Trust Model For Service Selection In General Service-Oriented Environments, Xing Su, Minjie Zhang, Yi Mu, Kwang Mong Sim Dec 2012

Pbtrust: A Priority-Based Trust Model For Service Selection In General Service-Oriented Environments, Xing Su, Minjie Zhang, Yi Mu, Kwang Mong Sim

Associate Professor Minjie Zhang

How to choose the best service provider (agent), which a service consumer can trust in terms of the quality and success rate of the service in an open and dynamic environment, is a challenging problem in many service-oriented applications such as Internet-based grid systems, e-trading systems, as well as service-oriented computing systems. This paper presents a Priority-Based Trust (PBTrust) model for service selection in general service-oriented environments. The PBTrust is robust and novel from several perspectives. (1) The reputation of a service provider is derived from referees who are third parties and had interactions with the provider in a rich …


Ontology-Based Knowledge Representation For A P2p Multi-Agent Distributed Intrusion Detection System, Dayong Ye, Quan Bai, Minjie Zhang Dec 2012

Ontology-Based Knowledge Representation For A P2p Multi-Agent Distributed Intrusion Detection System, Dayong Ye, Quan Bai, Minjie Zhang

Associate Professor Minjie Zhang

Many research efforts on application of ontology in network security have been done in the past decade. However, they mostly stop at initial proposal or focus on framework design without detailed representation of intrusion or attack and relevant detection knowledge with ontology. In this paper, the design and implementation of ontology-based knowledge representation for a peer-to-peer multi-agent distributed intrusion detection system (ontology-based MADIDS) are introduced. An example which demonstrates the representation of an attack with ontology and the relevant detection process is also presented. In ontology-Based MADIDS, ontology technique enables peers in the system and agents in one peer to …


An Ontology-Based Approach For Expert And Knowledge Mining In Complex Multi-Agent Systems, Minjie Zhang, Xijin Tang, Quan Bai, Jifa Gu Dec 2012

An Ontology-Based Approach For Expert And Knowledge Mining In Complex Multi-Agent Systems, Minjie Zhang, Xijin Tang, Quan Bai, Jifa Gu

Associate Professor Minjie Zhang

Complex problems require diverse expertise and multiple techniques to solve. In order to solve such problems, complex multi-agent systems include numbers of heterogeneous agents, which may include both of human experts and autonomous agents, to work together toward some complex problems. Most complex multi-agent systems are working in open domains. Due to heterogeneities and dynamic working environments, expertise and capabilities of agents might not be well estimated and presented in the system. Therefore, how to discover useful knowledge from human and autonomous experts, make more accurate estimation for experts' capabilities and to find out suitable expert(s) to solve incoming problems …


An Energy-Aware Multilevel Clustering Algorithm For Wireless Sensor Networks, Xinfang Yan, Jiangtao Xi, Joe F. Chicharo, Yanguang Yu Dec 2012

An Energy-Aware Multilevel Clustering Algorithm For Wireless Sensor Networks, Xinfang Yan, Jiangtao Xi, Joe F. Chicharo, Yanguang Yu

Dr Yanguang Yu

Clustering sensors nodes as the basic of routing is an efficient mechanism for prolonging the lifetime of wireless sensor networks. In this paper, the high-efficient multilevel clustering is abstracted as a root tree which has the performances of the minimal relay set and the maximal weight according to graph theory. A mathematical model for the clustering virtual backbone is built. Based on the model, an algorithm called energy-aware multilevel clustering (EAMC) is proposed. The EAMC can reduce the number of relays used for data transmission by minimizing the amount of the nodes in the root tree (that is cluster-head). Furthermore, …


An Estimation Method For Feedback Level Factor C Of A Self-Mixing Interferometry System, Yuanlong Fan, Yanguang Yu, Jiangtao Xi, Joe F. Chicharo Dec 2012

An Estimation Method For Feedback Level Factor C Of A Self-Mixing Interferometry System, Yuanlong Fan, Yanguang Yu, Jiangtao Xi, Joe F. Chicharo

Dr Yanguang Yu

This paper presents a fast estimation method for feedback level factor C of a self-mixing interferometry (SMI) system. The reconstruction of a displacement waveform using a SMI signal needs to know a C value. However, it is difficult to maintain a constant C value during the reconstruction process. We study the features of the reconstructed displacement waveforms incorporating different pre-set C values and classify waveforms into two types. Bisection method is introduced in our method for fast estimating C value. The effectiveness of our proposed method has been verified by both simulation and experimental data.


Towards Dynamic Formation Of Temporal Constraints For The Service Level Agreements Negotiation, Azlan Ismail, Jun Yan, Jun Shen Dec 2012

Towards Dynamic Formation Of Temporal Constraints For The Service Level Agreements Negotiation, Azlan Ismail, Jun Yan, Jun Shen

Dr Jun Yan

SLAs play an important role for the QoS-driven service composition. Meanwhile, the temporal constraints are one of the main elements in the management of SLA especially in specifying the validity period of the QoS offers. In practice, the temporal constraints should be generated dynamically by taking the resource capability of the provider into account. The generation should consider various parameters that influence the resource capability such as the expected duration of the required Web service, the amount of current utilization, the amount of available resources, the number of required time slots, etc. Therefore, this paper aims to elaborate this issue …


Dynamic Trust Model For Federated Identity Management, Hao Gao, Jun Yan, Yi Mu Dec 2012

Dynamic Trust Model For Federated Identity Management, Hao Gao, Jun Yan, Yi Mu

Dr Jun Yan

The goal of federated identity management is to allow principals, such as identities and attributes, to be shared across trust boundaries based on established policies. Since current Single Sign-On (SSO) mechanism excessively relies on the specifications of Circle of Trust (CoT), the need for service collaboration from different domains is being addressed on CoT. For the motivating issue of the cross-domain SSO mechanism, we need an emergent dynamic trust list for calculating the trust parties, thus, the CoT specifications require an initial effort on enrolling members automatically to adapt to the dynamic open environment. In this paper, we propose a …