Daniel Franklin | University of Technology Sydney (original) (raw)

Papers by Daniel Franklin

Journal of Instrumentation, 2013

2012 6th International Conference on Signal Processing and Communication Systems, 2012

Hostile and harsh environments may preclude the possibility of manual redeployment of new sensor ... more Hostile and harsh environments may preclude the possibility of manual redeployment of new sensor nodes, especially in the areas suffering from widespread damage and unbalanced node deployments. Distributed local relocations of currently deployed nodes is one promising solution to this problem. By using expected global node density and force-based movement algorithms inspired by the laws of nature, it is possible to address the aforementioned challenge. Force-based movement algorithms steer nodes towards their new locations based on the aggregation of exerted virtual forces on the node from their neighborhood. Some implicit assumptions about nodes' global status such as expected global node density are not realistic in dynamic and harsh environments. Thus, to conform to the uncertain nature and local interactions of nodes, a combination of radial-angular force fuzzy movement algorithms is suggested. The performance of the proposed model in terms of percentage of coverage, uniformity and average movement under three different boundary conditions are evaluated and compared with distributed self-spreading algorithms (DSSA). The results show that the simple fuzzy movement algorithm either outperforms or matches DSSA even if nodes don't benefit from expected global node density as in DSSA.

IEEE Nuclear Science Symposium Conference Record, 2009

2013 IEEE 78th Vehicular Technology Conference (VTC Fall), 2013

ABSTRACT In this paper we analyze the error performance of a cooperative multihop parallel relay ... more ABSTRACT In this paper we analyze the error performance of a cooperative multihop parallel relay network over Nakagami-m fading channels using M-ary Phase-shift keying (MPSK) modulation. We derive the general closed form expression of the symbol error probability (SEP) and present numerical results on the performance of the network.

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2011

Treatment of ocular cancers using eye plaque brachytherapy is now an established medical procedur... more Treatment of ocular cancers using eye plaque brachytherapy is now an established medical procedure. However, current QA for these eye plaques is quite rudimentary, limiting the opportunities for precise pretumour plaque customisation. This paper proposes and experimentally validates a new technique for imaging of eye plaque dose distributions using a high-resolution pixelated silicon detector. Results are presented demonstrating the 2D and 3D isodose surfaces produced using experimental data collected using this method.

Medical Physics, 2013

Purpose:High dose rate (HDR) brachytherapy is a form of radiation therapy for treating prostate c... more Purpose:High dose rate (HDR) brachytherapy is a form of radiation therapy for treating prostate cancer whereby a high activity radiation source is moved between predefined positions inside applicators inserted within the treatment volume. Accurate positioning of the source is essential in delivering the desired dose to the target area while avoiding radiation injury to the surrounding tissue. In this paper,HDR BrachyView, a novel inbody dosimetric imaging system for real time monitoring and verification of the radioactive seed position in HDR prostate brachytherapy treatment is introduced. The current prototype consists of a 15 × 60 mm2 silicon pixel detector with a multipinhole tungsten collimator placed 6.5 mm above the detector. Seven identical pinholes allow full imaging coverage of the entire treatment volume. The combined pinhole and pixel sensor arrangement is geometrically designed to be able to resolve the three‐dimensional location of the source. The probe may be rotated t...

Journal of Networks, 2012

ABSTRACT To achieve higher data rate or to extend the coverage range of a wireless communication ... more ABSTRACT To achieve higher data rate or to extend the coverage range of a wireless communication system, cooperative relay has been seen as a promising solution. This concept has been integrated in many traditional wireless communication networks. However, it has not been extensively examined for near field magnetic induction communication (NFMIC) systems. This paper aims to apply cooperative relay to NFMIC in a sense that is applicable to body area networking, since NFMIC is stated to be a suitable physical layer for body area networks. We have shown that using idle NFMIC nodes as relaying terminals, the system performance will be enhanced, as compared to a point to point communication system. In this context we have proposed three relaying methods to enhance the data rate and the received signal power in a personal area network. The relaying strategies are denoted as MI-Relay, MAMI Relay1 and MAMI Relay2. In this paper, using theoretical studies and simulation results, we have compared the performance of the three strategies and we have shown that higher data rates can be achieved through MAMI Relay1. However, we have discussed that the separation distance between relaying nodes and the source or destination can be a key factor for relay node selection.

Journal of Networks, 2013

munications and near field magnetic induction communication (NFMIC) is discussed. Three multihop ... more munications and near field magnetic induction communication (NFMIC) is discussed. Three multihop relay strategies for NFMIC are proposed: Non Line of Sight Magnetic Induction Relay (NLoS-MI Relay), Non Line of Sight Master/Assistant Magnetic Induction Relay1 (NLoS-MAMI Relay1) and Non Line of Sight Master/Assistant Magnetic Induction Relay2 (NLoS-MAMI Relay2). In the first approach only one node contributes to the communication, while in the other two techniques (which are based on a master-assistant strategy), two relaying nodes are employed. This paper shows that these three techniques can be used to overcome the problem of dead spots within a body area network and extend the communication range without increasing the transmission power and the antenna size or decreasing receiver sensitivity. The impact of the separation distance between the nodes on the achievable RSS and channel data rate is evaluated for the three techniques. It is demonstrated that the technique which is most effective depends on the specific network topology. Optimum selection of nodes as relay master and assistant based on the location of the nodes is discussed. The paper also studies the impact of the quality factor on achievable data rate. It is shown that to obtain the highest data rate, the optimum quality factor needs to be determined for each proposed cooperative communication method.

IEEE Transactions on Nuclear Science, 2009

Computer Networks, 2013

ABSTRACT This paper introduces DAFMAC (Decode And Forward MAC), a scalable opportunistic cooperat... more ABSTRACT This paper introduces DAFMAC (Decode And Forward MAC), a scalable opportunistic cooperative retransmission enhancement for the IEEE 802.11 MAC protocol which operates without the need for additional explicit control signalling. Distributed opportunistic retransmission algorithms rely on selecting a single suitable relay without direct arbitration between nodes. Simulations show that DAFMAC offers a significant improvement in fairness for both throughput and jitter, giving multiple parallel data flows a more equal opportunity to utilise the channel. DAFMAC cooperative retransmissions are shown to reduce node energy consumption for a given throughput. Further, the DAFMAC relay selection algorithm is shown to scale very well in terms of complexity and memory requirements in comparison to other cooperative retransmission schemes.

In WSNs, in order to recover from coverage holes and to mitigate their indirect/direct effects on... more In WSNs, in order to recover from coverage holes and to mitigate their indirect/direct effects on networks' performance, different recovery strategies such as increasing proximate nodes' transmission range and/or relocation of nodes towards coverage holes seem to be appropriate solutions. Since the majority of a mobile node's energy is consumed by movement and since nodes' residual energy may be affected by damage events, node movements should be performed sparingly. Conventional nodes' information exchange in real-time applications with security and interference concerns are neither practical nor secure. Therefore, for the aforementioned scenarios, at the price of possible node collisions, disconnections, and reasonable compromises, promising distributed and autonomous node movement algorithms based on limited 1-hop neighbour knowledge are proposed. Our proposed autonomous and constrained node movement model based on a node's 1-hop perception provides a feasible and rapid recovery mechanism for large scale coverage holes in real-time and harsh environments. Our model not only maintains moving nodes' connectivity to the rest of network to some extent, but also offers emergent cooperative recovery behaviour among autonomous moving nodes. Our movement model based on virtual chords formed by nodes and their real and virtual 1-hop neighbours, not only confines node movement range, but also takes the issue of moving nodes' connectivity into account. Suitable performance metrics for partial recovery via constrained movement are introduced to compare the performance and efficiency of our model with conventional Voronoi-based movement algorithms. Results show that our proposed model's performance is comparable with Voronoi-based movement algorithms. Index Terms-Coverage holes; autonomous and constrained movements; Wireless sensor networks; virtual chord.

Ad Hoc Networks, 2013

ABSTRACT On-demand routing protocols have the potential to provide scalable information delivery ... more ABSTRACT On-demand routing protocols have the potential to provide scalable information delivery in large ad hoc networks. The novelty of these protocols is in their approach to route discovery, where a route is determined only when it is required by initiating a route discovery procedure. Much of the research in this area has focused on reducing the route discovery overhead when prior knowledge of the destination is available at the source or by routing through stable links. Hence, many of the protocols proposed to date still resort to flooding the network when prior knowledge about the destination is un-available. This paper proposes a novel routing protocol for ad hoc networks, called On-demand Tree-based Routing Protocol (OTRP). This protocol combines the idea of hop-by-hop routing (as used by AODV) with an efficient route discovery algorithm called Tree-based Optimised Flooding (TOF) to improve scalability of ad hoc networks when there is no prior knowledge about the destination. To achieve this in OTRP, route discovery overheads are minimised by selectively flooding the network through a limited set of nodes, referred to as branching nodes. The key factors governing the performance of OTRP are theoretically analysed and evaluated, including the number of branch nodes, location of branching nodes and number of Route REQuest (RREQ) retries. It was found that the performance of OTRP (evaluated using a variety of well-known metrics) improves as the number of branching nodes increases and the number of consumed RREQ retries is reduced. Additionally, theoretical analysis and simulation results shows that OTRP outperforms AODV, DYMO, and OLSR with reduced overheads as the number of nodes and traffic load increases.

IEEE Nuclear Science Symposium Conference Record, 2012

A novel high resolution PET scanner dedicated to imaging small volumes (small animals or positron... more A novel high resolution PET scanner dedicated to imaging small volumes (small animals or positron mammography) has been developed. The system utilises a novel SiPM detector array coupled to a pixelated LYSO scintillator and placed in an edge-on formation around the ring. The unique design provides a more accurate placement of the Lines of Response (LoR) by measuring the Depth of Interaction (DoI) which results in a uniform spatial resolution across the whole field of view (FoV). Analytical modelling of the effect of parallax error on spatial resolution is presented. A full prototype of the system is simulated using GATE/GEANT4 with Ge-68 point sources placed at various positions within the FoV. The simulation results are compared to experimental measurements on the prototype system, and the effectiveness of the proposed approach to determining the DoI is demonstrated. The effectiveness of the DoI estimation in achieving a uniform spatial resolution across the entire FoV is demonstrated where a 30% improvement in spatial resolution close to the outer edge of the gantry ring is obtained. Preliminary images of a micro-Defrise phantom filled with F-18 obtained using the prototype system are presented and compared with a simulation of the same configuration.

2017 IEEE 85th Vehicular Technology Conference (VTC Spring), 2017

The CORNER propagation model, first proposed in 2010, has been previously validated and found to ... more The CORNER propagation model, first proposed in 2010, has been previously validated and found to be a reasonably accurate representation of propagation scenarios in urban Vehicular Ad Hoc Networks (VANETs). This paper considers the impact of the propagation environment on routing performance and reveals a pressing need to consider more accurate propagation models when designing urban VANET routing protocols. A greedy routing protocol, which uses CORNER's propagation estimates for neighbour selection, is then presented. The new protocol, named Corner Propagation Stateless Routing (CPSR) is compared to GPSR, a benchmark protocol for VANETs, showing between 87% and 300% improvement in packet delivery ratio at higher network loads.

Medical Physics, 2021

PurposeEfficient compression of images while preserving image quality has the potential to be a m... more PurposeEfficient compression of images while preserving image quality has the potential to be a major enabler of effective remote clinical diagnosis and treatment, since poor Internet connection conditions are often the primary constraint in such services. This paper presents a framework for organ‐specific image compression for teleinterventions based on a deep learning approach and anisotropic diffusion filter.MethodsThe proposed method, deep learning and anisotropic diffusion (DLAD), uses a convolutional neural network architecture to extract a probability map for the organ of interest; this probability map guides an anisotropic diffusion filter that smooths the image except at the location of the organ of interest. Subsequently, a compression method, such as BZ2 and HEVC‐visually lossless, is applied to compress the image. We demonstrate the proposed method on three‐dimensional (3D) CT images acquired for radio frequency ablation (RFA) of liver lesions. We quantitatively evaluate...

Scientific Reports, 2019

This work presents a simulation study evaluating relative biological effectiveness at 10% surviva... more This work presents a simulation study evaluating relative biological effectiveness at 10% survival fraction (RBE10) of several different positron-emitting radionuclides in heavy ion treatment systems, and comparing these to the RBE10s of their non-radioactive counterparts. RBE10 is evaluated as a function of depth for three positron-emitting radioactive ion beams (10C, 11C and 15O) and two stable ion beams (12C and 16O) using the modified microdosimetric kinetic model (MKM) in a heterogeneous skull phantom subject to a rectangular 50 mm × 50 mm × 60 mm spread out Bragg peak. We demonstrate that the RBE10 of the positron-emitting radioactive beams is almost identical to the corresponding stable isotopes. The potential improvement in PET quality assurance image quality which is obtained when using radioactive beams is evaluated by comparing the signal to background ratios of positron annihilations at different intra- and post-irradiation time points. Finally, the incidental dose to th...

Physics in Medicine & Biology, 2018

This paper presents a simulation study of BrachyShade, a proposed internal source-tracking system... more This paper presents a simulation study of BrachyShade, a proposed internal source-tracking system for real time quality assurance in high dose rate prostate brachytherapy. BrachyShade consists of a set of spherical tungsten occluders located above a pixellated silicon photodetector. The source location is estimated by minimising the mean squared error between a parametric model of the shadow image and acquired images of the shadows projected on the detector plane. A novel algorithm is finally employed to correct the systemic error resulting from Compton scattering in the medium. The worst-case error obtained with BrachyShade for a 13.5 ms image acquisition is less than 1.3 mm in the most distant part of the treatment volume, while for 75% of source locations an error of less than 0.42 mm was achieved.

Scientific Reports, 2018

This paper presents Neutron Capture Enhanced Particle Therapy (NCEPT), a method for enhancing the... more This paper presents Neutron Capture Enhanced Particle Therapy (NCEPT), a method for enhancing the radiation dose delivered to a tumour relative to surrounding healthy tissues during proton and carbon ion therapy by capturing thermal neutrons produced inside the treatment volume during irradiation. NCEPT utilises extant and in-development boron-10 and gadolinium-157-based drugs from the related field of neutron capture therapy. Using Monte Carlo simulations, we demonstrate that a typical proton or carbon ion therapy treatment plan generates an approximately uniform thermal neutron field within the target volume, centred around the beam path. The tissue concentrations of neutron capture agents required to obtain an arbitrary 10% increase in biological effective dose are estimated for realistic treatment plans, and compared to concentrations previously reported in the literature. We conclude that the proposed method is theoretically feasible, and can provide a worthwhile improvement in...

2015 9th International Conference on Signal Processing and Communication Systems (ICSPCS), 2015

Unlike sporadic node failures, coverage holes emerging from multiple temporally-correlated node f... more Unlike sporadic node failures, coverage holes emerging from multiple temporally-correlated node failures can severely affect quality of service in a network and put the integrity of entire wireless sensor networks at risk. Conventional topology control schemes addressing such undesirable topological changes have usually overlooked the status of participating nodes in the recovery process with respect to the deployed sink node(s) in the network. In this paper, a cooperative coverage hole recovery model is proposed which utilises the simple geometrical procedure of circle inversion. In this model, autonomous nodes consider their distances to the deployed sink node(s) in addition to their local status, while relocating towards the coverage holes. By defining suitable metrics, the performance of our proposed model performance is compared with a force-based approach.