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- Associate Professor Adam Rennie (16)
- William E. Price (12)
- Dr Lasantha G Meegahapola (9)
- Professor Farzad Safaei (6)
- zengxi pan (6)
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- Anatoly Rozenfeld (5)
- Alex Remennikov (4)
- Dr Fenghui Ren (4)
- Dr Philip Ciufo (4)
- Nathan Larkin (4)
- Shi Xue Dou (4)
- Brian Monaghan (3)
- David Hastie (3)
- Dr Ian Piper (3)
- Faisal I Hai (3)
- Professor Katina Michael (3)
- Ah Chung Tsoi (2)
- Dr Guomin Yang (2)
- Dr Raad Raad (2)
- Farhad Fakheri Raof (2)
- George Takacs (2)
- Ishraq Hamdan Alfadhli (2)
- Jianli Wang (2)
- Paul F. Eschenfelder (2)
- Professor David Steel (2)
- Veysel Yazici (2)
- Cher Hau Seng (1)
- Dr Mark Freeman (1)
- Josip Horvat (1)
- Long D Nghiem (1)
Articles 31 - 60 of 118
Full-Text Articles in Science and Technology Studies
An Adaptive Bilateral Negotiation Model Based On Bayesian Learning, Chao Yu, Fenghui Ren, Minjie Zhang
An Adaptive Bilateral Negotiation Model Based On Bayesian Learning, Chao Yu, Fenghui Ren, Minjie Zhang
Dr Fenghui Ren
Endowing the negotiation agent with a learning ability such that a more beneficial agreement might be obtained is increasingly gaining attention in agent negotiation research community. In this paper, we propose a novel bilateral negotiation model based on Bayesian learning to enable self-interested agents to adapt negotiation strategies dynamically during the negotiation process. Specifically, we assume that two agents negotiate over a single issue based on time-dependent tactic. The learning agent has a belief about the probability distribution of its opponent's negotiation parameters (i.e., the deadline and reservation offer). By observing opponent's historical offers and comparing them with the fitted …
Dynamic Testing Of Tekseal High Yield Grout To Provide An Orepass Plug Designed For Impact, I V. S Mutton, Alexander Remennikov, D Pateman
Dynamic Testing Of Tekseal High Yield Grout To Provide An Orepass Plug Designed For Impact, I V. S Mutton, Alexander Remennikov, D Pateman
Alex Remennikov
Significant wear in orepasses particularly in the brow and chute areas is proportional to the tonnage throughput with increased wear associated with running orepasses empty. During planned shutdowns it may be necessary to isolate maintenance crews from objects falling from orepasses. In the last 15 years grout orepass plugs that can later be easily removed have been poured above chute maintenance areas. These provide protection from high energy impact and isolating workers from the hazard. Construction and removal methods will be briefly explained. Since it is not feasible to investigate the problem of orepass plug impact response using full-scale experimental …
Utilising Non-Composite Steel-Concrete-Steel Panels For Protective Structures, A M. Remennikov, S Y. Kong, Brian Uy
Utilising Non-Composite Steel-Concrete-Steel Panels For Protective Structures, A M. Remennikov, S Y. Kong, Brian Uy
Alex Remennikov
A high-performance protective structure utilising non-composite steel-concrete-steel (SCS) sandwich panels for protecting buildings and facilities against close-range detonation of VBIEDs and heavy ve-hicle impacts has been developed. Unlike other existing composite sandwich panels, no shear connec-tors between the steel faceplates are utilised to construct protective panels in order to simplify the con-struction process. The concrete core of the panel is included to provide the mass for increased inertia effects, and the steel faceplates are designed to develop tensile membrane resistance at large displace-ment to dissipate impulsive energy. The energy dissipation capability and high ductility of the axially-restrained non-composite SCS panels …
Reliability-Based Conversion Of A Structural Design Code For Railway Prestressed Concrete Sleepers, A M. Remennikov, Martin Murray, Sakdirat Kaewunruen
Reliability-Based Conversion Of A Structural Design Code For Railway Prestressed Concrete Sleepers, A M. Remennikov, Martin Murray, Sakdirat Kaewunruen
Alex Remennikov
"Ballasted railway track is very suitable for heavy-rail networks because of its many superior advantages in design, construction, short- and long-term maintenance, sustainability, and life cycle cost. An important part of the railway track system, which distributes the wheel load to the formation, is the railway sleeper. Improved knowledge has raised concerns about design techniques for prestressed concrete (PC) sleepers. Most current design codes for these rely on allowable stresses and material strength reductions. However, premature cracking of PC sleepers has been found in railway tracks. The major cause of cracking is the infrequent but high-magnitude wheel loads produced by …
The Response Of Axially Restrained Non-Composite Steel-Concrete-Steel Sandwich Panels Due To Large Impact Loading, Alex M. Remennikov, Sih Ying Kong, Brian Uy
The Response Of Axially Restrained Non-Composite Steel-Concrete-Steel Sandwich Panels Due To Large Impact Loading, Alex M. Remennikov, Sih Ying Kong, Brian Uy
Alex Remennikov
In conventional steel-concrete-steel (SCS) construction, the external steel plates are connected to the concrete infill by welded shear stud connectors. This paper describes a programme of experimental and numerical investigations on reduced-scale non-composite SCS panels with axially restrained connections. The experimental results have demonstrated that the non-composite SCS panels are capable of developing enhanced load-carrying capacity through the tensile membrane resistance of the steel faceplates. This type of construction was found to exhibit highly ductile response and be able to sustain large end rotations of up to 18° without collapse. High fidelity finite element models for SCS panels under impact …
Riemannian Manifolds In Noncommutative Geometry, Steven Lord, Adam Rennie, Joseph C. Varilly
Riemannian Manifolds In Noncommutative Geometry, Steven Lord, Adam Rennie, Joseph C. Varilly
Associate Professor Adam Rennie
We present a definition of Riemannian manifold in noncommutative geometry. Using products of unbounded Kasparov modules, we show one can obtain such Riemannian manifolds from noncommutative spinc manifolds; and conversely, in the presence of a spinc structure. We also show how to obtain an analogue of Kasparov's fundamental class for a Riemannian manifold, and the associated notion of Poincaré duality. Along the way we clarify the bimodule and first-order conditions for spectral triples.
Modular Index Invariants Of Mumford Curves, Adam C. Rennie, Alan L. Carey, M Marcolli
Modular Index Invariants Of Mumford Curves, Adam C. Rennie, Alan L. Carey, M Marcolli
Associate Professor Adam Rennie
We continue an investigation initiated by Consani–Marcolli of the relation between the algebraic geometry of p-adic Mumford curves and the noncommutative geometry of graph C∗-algebras associated to the action of the uniformizing p-adic Schottky group on the Bruhat–Tits tree. We reconstruct invariants of Mumford curves related to valuations of generators of the associated Schottky group, by developing a graphical theory for KMS weights on the associated graph C∗-algebra, and using modular index theory for KMS weights. We give explicit examples of the construction of graph weights for low genus Mumford curves. We then show that the theta functions of Mumford …
The Chern Character Of Semifinite Spectral Triples, Alan L. Carey, John Phillips, Adam C. Rennie, Fyodor A. Sukochev
The Chern Character Of Semifinite Spectral Triples, Alan L. Carey, John Phillips, Adam C. Rennie, Fyodor A. Sukochev
Associate Professor Adam Rennie
In previous work we generalised both the odd and even local index formula of Connes and Moscovici to the case of spectral triples for a ∗-subalgebra A of a general semifinite von Neumann algebra. Our proofs are novel even in the setting of the original theorem and rely on the introduction of a function valued cocycle (called the resolvent cocycle) which is 'almost' a (b,B)-cocycle in the cyclic cohomology of A. In this paper we show that this resolvent cocycle 'almost' represents the Chern character, and assuming analytic continuation properties for zeta functions, we show that the associated residue cocycle, …
Pseudo-Riemannian Spectral Triples And The Harmonic Oscillator, Koen Van Den Dungen, Mario Paschke, Adam C. Rennie
Pseudo-Riemannian Spectral Triples And The Harmonic Oscillator, Koen Van Den Dungen, Mario Paschke, Adam C. Rennie
Associate Professor Adam Rennie
We define pseudo-Riemannian spectral triples, an analytic context broad enough to encompass a spectral description of a wide class of pseudo-Riemannian manifolds, as well as their noncommutative generalisations. Our main theorem shows that to each pseudo-Riemannian spectral triple we can associate a genuine spectral triple, and so a K-homology class. With some additional assumptions we can then apply the local index theorem. We give a range of examples and some applications. The example of the harmonic oscillator in particular shows that our main theorem applies to much more than just classical pseudo-Riemannian manifolds. 2013 Elsevier B.V.
Kk-Theory And Spectral Flow In Von Neumann Algebras, J Kaad, R Nest, Adam C. Rennie
Kk-Theory And Spectral Flow In Von Neumann Algebras, J Kaad, R Nest, Adam C. Rennie
Associate Professor Adam Rennie
We present a definition of spectral flow for any norm closed ideal J in any von Neumann algebra N. Given a path of selfadjoint operators in N which are invertible in N/J, the spectral flow produces a class in Ko(J).Given a semifinite spectral triple (A, H, D) relative to (N, t) with A separable, we construct a class [D] ? KK1(A, K(N)). For a unitary u ? A, the von Neumann spectral flow between D and u*Du is equal to the Kasparov product [u]A[D], and is simply related to the numerical spectral flow, and a refined C*-spectral flow.
Dynamic Channel Allocation For Mobile Cellular Systems Using A Control Theoretical Approach, Yaya Wei, Chuang Lin, Raad Raad, Fengyuan Ren
Dynamic Channel Allocation For Mobile Cellular Systems Using A Control Theoretical Approach, Yaya Wei, Chuang Lin, Raad Raad, Fengyuan Ren
Dr Raad Raad
The guard channel scheme in wireless mobile networks has attracted and is still drawing research interest owing to easy implementation and flexible control. Dynamic guard channel schemes have already been proposed in the literature to adapt to varying traffic load. This paper presents a novel control-theoretic approach to dynamically reserve guard channels called PI-Guard Channel (PI-GC) controller that maintains the handoff blocking probability (HBP) to a predefined value; while it still improves the channel resource utilization.
Noncommutative Atiyah-Patodi-Singer Boundary Conditions And Index Pairings In Kk-Theory, Alan L. Carey, John Phillips, Adam C. Rennie
Noncommutative Atiyah-Patodi-Singer Boundary Conditions And Index Pairings In Kk-Theory, Alan L. Carey, John Phillips, Adam C. Rennie
Associate Professor Adam Rennie
We investigate an extension of ideas of Atiyah-Patodi-Singer (APS) to a noncommutative geometry setting framed in terms of Kasparov modules. We use a mapping cone construction to relate odd index pairings to even index pairings with APS boundary conditions in the setting of KK-theory, generalising the commutative theory. We find that Cuntz-Krieger systems provide a natural class of examples for our construction and the index pairings coming from APS boundary conditions yield complete K-theoretic information about certain graph C*-algebras
Twisted Cyclic Cohomology And Modular Fredholm Modules, Adam Rennie, Andrzej Sitarz, Makoto Yamashita
Twisted Cyclic Cohomology And Modular Fredholm Modules, Adam Rennie, Andrzej Sitarz, Makoto Yamashita
Associate Professor Adam Rennie
Connes and Cuntz showed in [Comm. Math. Phys. 114 (1988), 515-526] that suitable cyclic cocycles can be represented as Chern characters of finitely summable semifinite Fredholm modules. We show an analogous result in twisted cyclic cohomology using Chern characters of modular Fredholm modules. We present examples of modular Fredholm modules arising from Podles sphereś and from SUq (2).
Spectral Flow Invariants And Twisted Cyclic Theory For The Haar State On Suq(2), A L. Carey, A Rennie, K Tong
Spectral Flow Invariants And Twisted Cyclic Theory For The Haar State On Suq(2), A L. Carey, A Rennie, K Tong
Associate Professor Adam Rennie
In [A.L. Carey, J. Phillips, A. Rennie, Twisted cyclic theory and an index theory for the gauge invariant KMS state on Cuntz algebras. arXiv:0801.4605], we presented a K-theoretic approach to finding invariants of algebras with no non-trivial traces. This paper presents a new example that is more typical of the generic situation. This is the case of an algebra that admits only non-faithful traces, namely SUq.2/ and also KMS states. Our main results are index theorems (which calculate spectral flow), one using ordinary cyclic cohomology and the other using twisted cyclic cohomology, where the twisting comes from the generator of …
Spectral Triples: Examples And Index Theory, Alan L. Carey, John Phillips, Adam C. Rennie
Spectral Triples: Examples And Index Theory, Alan L. Carey, John Phillips, Adam C. Rennie
Associate Professor Adam Rennie
The main objective of these notes is to give some intuition about spectral triples and the role they play in index theory. The notes are basically a road map, with much detail omitted. To give a complete account of all the topics covered would require at least a book, so we have opted for a sketch.
The Dixmier Trace And Asymptotics Of Zeta Functions, Alan L. Carey, Adam C. Rennie, Aleksandr Sedaev, Fyodor A. Sukochev
The Dixmier Trace And Asymptotics Of Zeta Functions, Alan L. Carey, Adam C. Rennie, Aleksandr Sedaev, Fyodor A. Sukochev
Associate Professor Adam Rennie
We obtain general theorems which enable the calculation of the Dixmier trace in terms of the asymptotics of the zeta function and of the trace of the heat semigroup. We prove our results in a general semi-finite von Neumann algebra. We find for p > 1 that the asymptotics of the zeta function determines an ideal strictly larger than Lp,∞ on which the Dixmier trace may be defined. We also establish stronger versions of other results on Dixmier traces and zeta functions.
Twisted Cyclic Theory And An Index Theory For The Gauge Invariant Kms State On Cuntz Algebras On, Alan L. Carey, John Phillips, Adam C. Rennie
Twisted Cyclic Theory And An Index Theory For The Gauge Invariant Kms State On Cuntz Algebras On, Alan L. Carey, John Phillips, Adam C. Rennie
Associate Professor Adam Rennie
This paper presents, by example, an index theory appropriate to algebras without trace. Whilst we work exclusively with the Cuntz algebras the exposition is designed to indicate how to develop a general theory. Our main result is an index theorem (formulated in terms of spectral flow) using a twisted cyclic cocycle where the twisting comes from the modular automorphism group for the canonical gauge action on the Cuntz algebra. We introduce a modified K1-group of the Cuntz algebra so as to pair with this twisted cocycle. As a corollary we obtain a noncommutative geometry interpretation for Araki's notion of relative …
A Novel Destination-Based Routing Protocol (Dbrp) In Dtns, Saeid Iranmanesh, Raad Raad, Kwan-Wu Chin
A Novel Destination-Based Routing Protocol (Dbrp) In Dtns, Saeid Iranmanesh, Raad Raad, Kwan-Wu Chin
Dr Raad Raad
In Delay Tolerant Networks (DTNs), the aim of any forwarding/routing protocols is to achieve a high delivery ratio of packets/bundles at the lowest possible bandwidth cost, buffer space and energy. Therefore, finding a protocol which uses less resource to achieve high delivery ratio and low latency is an open research question. This paper proposes a quota-based protocol which confines the number of replicas and forwards them based on the meeting history of nodes. The unique aspect of our protocol is to weight any encounter with the final destination to be much higher than any other node encounter. This aspect of …
Semifinite Spectral Triples Associated With Graph C*-Algebras, Alan L. Carey, John Phillips, Adam Rennie
Semifinite Spectral Triples Associated With Graph C*-Algebras, Alan L. Carey, John Phillips, Adam Rennie
Associate Professor Adam Rennie
We review the recent construction of semifinite spectral triples for graph C^*-algebras. These examples have inspired many other developments and we review some of these such as the relation between the semifinite index and the Kasparov product, examples of noncommutative manifolds, and an index theorem in twisted cyclic theory using a KMS state.
Twisted Cyclic Theory, Equivariant Kk-Theory And Kms States, Alan L. Carey, Sergey Neshveyev, R Nest, Adam Rennie
Twisted Cyclic Theory, Equivariant Kk-Theory And Kms States, Alan L. Carey, Sergey Neshveyev, R Nest, Adam Rennie
Associate Professor Adam Rennie
Given a C-algebra A with a KMS weight for a circle action, we construct and compute a secondary invariant on the equivariant K-theory of the mapping cone of AT ,! A, both in terms of equivariant KK-theory and in terms of a semifinite spectral flow. This in particular puts the previously considered examples of Cuntz algebras [10] and SUqð2Þ [14] in a general framework. As a new example we consider the Araki-Woods IIIl representations of the Fermion algebra.
Families Of Type Iii Kms States On A Class Of C-Algebras Containing On And Qn, A L. Carey, J Phillips, I F. Putnam, A Rennie
Families Of Type Iii Kms States On A Class Of C-Algebras Containing On And Qn, A L. Carey, J Phillips, I F. Putnam, A Rennie
Associate Professor Adam Rennie
We construct a family of purely infinite C¤-algebras, Q¸ for ¸ 2 (0, 1) that are classified by their K-groups. There is an action of the circle T with a unique KMS state à on each Q¸. For ¸ = 1/n, Q1/n »= On, with its usual T action and KMS state. For ¸ = p/q, rational in lowest terms, Q¸ »= On (n = q − p + 1) with UHF fixed point algebra of type (pq)1. For any n > 1, Q¸ »= On for infinitely many ¸ with distinct KMS states and UHF fixed-point algebras. For any ¸ …
Orbifolds Are Not Commutative Geometries, Adam C. Rennie, Joseph C. Varilly
Orbifolds Are Not Commutative Geometries, Adam C. Rennie, Joseph C. Varilly
Associate Professor Adam Rennie
In this note we show that the crucial orientation condition for commutative geometries fails for the natural commutative spectral triple of an orbifold M/G.
Inertial Sensing For Human Motor Control Symmetry In Injury Rehabilitation, Matthew Field, David Stirling, Montserrat Ros, Zengxi Stephen Pan, Fazel Naghdy
Inertial Sensing For Human Motor Control Symmetry In Injury Rehabilitation, Matthew Field, David Stirling, Montserrat Ros, Zengxi Stephen Pan, Fazel Naghdy
zengxi pan
This paper proposes a series of methods for representing changes in human motion during injury rehabilitation using Micro-Electro-Mechanical Systems (MEMS) inertial sensors. Tracking the changes over a recovery period requires methods for evaluating the similarity of movement in an impaired state against a non-impaired state. We investigate the use of motion analyses such as the centre of mass (COM) tipping distance, the variance of joint velocity eigenvalues and the cumulative state changes of Gaussian mixture models (GMM) for monitoring the symmetry between the left and right sides of body during rehabilitation exercises. The methods are tested on an injured athlete …
Recent Progress On Programming Methods For Industrial Robots, Zengxi Pan, Joseph Polden, Nathan Larkin, Stephen Van Duin, John Norrish
Recent Progress On Programming Methods For Industrial Robots, Zengxi Pan, Joseph Polden, Nathan Larkin, Stephen Van Duin, John Norrish
zengxi pan
"Although an automated flexible production cell is an intriguing prospect for small to median enterprises (SMEs) in current global market conditions, the complexity of programming remains one of the major hurdles preventing automation using industrial robots for SMEs. This paper provides a comprehensive review of the recent research progresses on the programming methods for industrial robots, including online programming, offline programming (OLP), and programming using Augmented Reality (AR). With the development of more powerful 3D CAD/PLM software, computer vision, sensor technology, etc. new programming methods suitable for SMEs are expected to grow in years to come. (C) 2011 Elsevier Ltd. …
Development Of A Dc-Lsnd Welding Process For Gmaw On Dh-36 Steel, Raymond Holder, Nathan Larkin, Huijun Li, Lenka Kuzmikova, Zengxi Pan, John Norrish
Development Of A Dc-Lsnd Welding Process For Gmaw On Dh-36 Steel, Raymond Holder, Nathan Larkin, Huijun Li, Lenka Kuzmikova, Zengxi Pan, John Norrish
zengxi pan
Weld induced distortion correction is a major cost within the shipbuilding industry. This paper investigates the use of an active cooling process known as Dynamically Controlled - Low Stress No Distortion (DC-LSND) Welding on DH-36 steel. Thermal profiles are obtained and distortion measurements are also achieved. Results show that the application of a localised cryogenic cooling source trailing the welding arc can significantly reduce weld induced distortion using the GMAW process. The effect of forced cooling on the weld microstructure is also observed.
Development Of Safe Optimized Welding Procedures For High Strength Q&T Steel Welded With Austenitic Consumables, Lenka Kuzmikova, Huijun Li, John Norrish, Zengxi Stephen Pan, Nathan Larkin
Development Of Safe Optimized Welding Procedures For High Strength Q&T Steel Welded With Austenitic Consumables, Lenka Kuzmikova, Huijun Li, John Norrish, Zengxi Stephen Pan, Nathan Larkin
zengxi pan
High strength quenched and tempered (Q&T) steels offer obvious economic benefits originating from their advantageous strength to price and weight ratios. These steels are usually welded using ferritic consumables and for this combination the risk of hydrogen assisted cold cracking (HACC) is high. The use of austenitic stainless steel (ASS) consumables has great potential to significantly improve this issue. Yet, there are no guidelines for determination of safe level of preheat for welding ferritic steels with ASS consumables. For this reason manufacturers adopt this parameter from procedures developed for conventional ferritic consumables thus significantly limiting the benefits ASS consumables are …
Investigation Into Feasibility Of Hybrid Laser-Gmaw Process For Welding High Strength Quenched And Tempered Steel, Lenka Kuzmikova, Nathan Larkin, Zengxi Pan, Mark Callaghan, Huijun Li, John Norrish
Investigation Into Feasibility Of Hybrid Laser-Gmaw Process For Welding High Strength Quenched And Tempered Steel, Lenka Kuzmikova, Nathan Larkin, Zengxi Pan, Mark Callaghan, Huijun Li, John Norrish
zengxi pan
In this study, the feasibility of hybrid laser-gas metal arc welding process for replacement of conventional flux-cored arc welding procedure for welding high strength quenched and tempered steel was investigated. Experimental work focused on optimisation of process parameters to produce joint with desired properties. Hardness of the weld heat affected zone produced by both processes has been measured. Productivity and cost effectiveness of both processes were compared. It was concluded that hybrid laser-gas metal arc welding process is suitable for welding high strength quenched and tempered steel.
Offline Programming For Short Batch Robotic Welding, Nathan Larkin, Aleksandar Milojevic, Zengxi Pan, Joseph Polden, John Norrish
Offline Programming For Short Batch Robotic Welding, Nathan Larkin, Aleksandar Milojevic, Zengxi Pan, Joseph Polden, John Norrish
zengxi pan
Robotics based automation has many advantages over both manual operation and dedicated hard automation. In practice however the robot programming overhead and high cost of dedicated jigging are serious impediments to its use for short production runs. Offline programming packages offer an attractive alternative to reduce programming time and robot down time, however many of the available packages are fairly complex and treat the geometric programming and welding operation separately. The paper will describe the development of alternative approaches and the evaluation of an integrated offline robotic welding package (RinasWeld) which addresses these issues and makes low volume robotic welding …
Methods For Usability Evaluations Of Mobile Devices, Fayez Alshehri, Mark Freeman
Methods For Usability Evaluations Of Mobile Devices, Fayez Alshehri, Mark Freeman
Dr Mark Freeman
The usability of applications designed and developed for mobile devices integral user experience, particularly for current touch-screen mobile devices. This conceptual paper provides a profile of the ways in which mobile device usability evaluation methods are being adapted to better reflect technological. With an increasing capacity for greater user interactivity through a range of tasks and in a variety of contexts, the importance and impact of mobile device context-of-use components is of particular interest to researchers. This requires a need for a shift in evaluation method paradigms with a particular focus on methods involving the user, as part of the …
Complementary Techniques For Probing Terahertz Magnetic Excitations In Cu3bi(Seo3)2o2cl, K H. Miller, E Constable, H Berger, D B. Tanner, J Horvat, R A. Lewis
Complementary Techniques For Probing Terahertz Magnetic Excitations In Cu3bi(Seo3)2o2cl, K H. Miller, E Constable, H Berger, D B. Tanner, J Horvat, R A. Lewis
Josip Horvat
A low frequency magnetic excitation in Cu3Bi(SeO 3)2O2Cl has been studied through complementary spectroscopic techniques which utilised terahertz radiation from a synchrotron, a mercury arc lamp, and a two-colour photomixing system. The excitation has been studied at temperatures down to 5K and in magnetic fields up to 10T. © 2012 IEEE.