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Contact Logics provide a natural framework for representing and reasoning about regions in several areas of computer science. In this paper, we focus our attention on reasoning methods for Contact Logics and address the satisfiability problem and the unifiability problem. Firstly, we give sound and complete tableaux-based decision procedures in Contact Logics and we obtain new results about the decidability/complexity of the satisfiability problem in these logics. Secondly, we address the computability of the unifiability problem in Contact Logics and we obtain new results about the unification type of the unifiability problem in these logics.

An original and an effective method for the analysis of the dc-link voltage ripple for single-phase multilevel inverters based on H-bridge and level doubling network (LDN) is given in this paper. The LDN is basically a half-bridge fed by a floating capacitor, without the need of an additional dc supply and with voltage self-balancing capability, able to increase (double) the number of output voltage levels. This configuration is particularly suitable for single-phase single-stage grid-connected photovoltaic (PV) systems, and the LDN cell can be seen also as a retrofit for existing H-bridge configurations. In order to address the design of the conversion system, with particular reference to the dc-link capacitor, PV current and voltage ripples are analytically determined and verified by experimental tests.

Robustness, security, anonymity, and scalability are valued features for mobile ad hoc network routing protocols. Unfortunately, the existing ad hoc routing protocols have limitations in each area. In this paper, we first analyze several existing mobile ad hoc routing protocols for robustness, security, anonymity, and scalability. Based on the analysis, we propose a new robust anonymous ad hoc on-demand routing protocol based on a proposed anonymous neighborhood trust model. We demonstrate that the protocol has strong security and anonymity protection, better scalability and is more robust when compared with other protocols., MILCOM 2009 - 2009 IEEE Military Communications Conference, October 18-21 2009, Boston, MA, USA

International audience; This paper addresses the localization and super-resolutionof license plate in a unifying approach. Higher qualitylicense plate can be obtained using super-resolution onsuccessive lower resolution plate images. All existingmethods assume that plate zones are correctly extractedfrom every frame. However, the accurate localization needsa sufficient quality of the image, which is not always truein real video. Super-resolution on all pixels is a possiblebut much time consuming alternative. We propose a frameworkwhich interlaces successfully these two modules. First,coarse candidates are found by an weak but fast licenseplate detection based on edge map sub-sampling. Then, animproved fast MAP-based super-resolution, using local phaseaccurate registration and edge preserving prior, is appliedon these regions of interest. Finally, our robustICHT-based localizer rejects false-alarms and localizes thehigh resolution license plate more accurately. Experimentswhich were conducted on synthetic and real data, proved therobustness of our approach with real-time possibility.

It is inevitable for data collection that IoT sensors are distributed to interested areas. However, not only the proper placement of sensors, but also the replacement of sensors that have run out of energy is very difficult. As a remedy, wireless charging systems for IoT sensors have been researched recently, but it is apparent that the availability of charging system is limited especially for IoT sensors scattered in rugged terrain. Thus, it is important that the sensor relocation models to recover sensing holes employ energy-efficient scheme. While there are various methods in the mobile model of wireless sensors, well-known wheel-based movements in rough areas are hard to achieve. Thus, research is ongoing in various areas of the hopping mobile model in which wireless sensors jump. Many past studies about hopping sensor relocation assume that all sensor nodes are aware of entire network information throughout the network. These assumptions do not fit well to the actual environment, and they are nothing but classical theoretical research. In addition, the physical environment (sand, mud, etc.) of the area in which the sensor is deployed can change from time to time. In this paper, we overcome the theoretical-based problems of the past researches and propose a new realistic hopping sensor relocation protocol considering terrain conditions. Since the status of obstacles around the sensing hole is unknown, the success rate of the hopping sensor relocation is used to predict the condition of the surrounding environment. Also, we are confident that our team is uniquely implementing OMNeT++ (Objective Modular Network Testbed in C++) simulation in the hopping sensor relocation protocol to reflect the actual communication environment. Simulations have been performed on various obstacles for performance evaluation and analysis, and we are confident that better energy efficiency with later appearance of sensing holes can be achieved compared to well-known relocation protocols.

Publisher's version (útgefin grein), This paper is motivated by the notion that coupling systems allows for mitigating the failure of individual ones. We present a novel approach to determining asymptotic stability and robustness of a network consisting of coupled dynamical systems, where individual system dynamics are represented through polynomial or rational functions. The analysis relies on a local analysis; thus, making it computationally implementable. We present an efficient computational method that relies on semidefinite programming. Importantly, for cases where multiple equilibrium points exist, we show how to determine regions around an asymptotically stable equilibrium point that bounds solutions. These regions increase when systems are coupled as we observe when applying the presented analysis framework to a mathematical model of a continuous stirred tank reactor. Importantly, the presented work has implications to other fields as well., "Peer Reviewed"

International audience; Mimicry and deferred imitation have often been considered as separate kinds of imitation. In this paper, we present a simple architecture for robotic arm control which can be used for both. The model is based on some dynamical equations, which provide a motor control with exploring and converging capacities. A visuo-motor map is used to associate positions of the end effector in the visual space with proprioceptive position of the robotic arm. It enables a fast learning of the visuo-motor associations without needing to embed a priori information. The controller can be used both for accurate control and interaction. It has been implemented on a minimal robotic setup showing some interesting emergent properties. The robot can reproduce simple gestures in mimicry situation and finalized actions in deferred imitation situation. Moreover, it can even show some “intention” recognition abilities. Finally, the experiment of deferred imitation which inherits from learning by demonstration, also provides a good basis for cooperative and interactive experiments.

Modern data analytics applications typically process massive amounts of data on clusters of tens, hundreds, or thousands of machines to support near-real-time decisions.The quantity of data and limitations of disk and memory bandwidth often make it infeasible to deliver answers at interactive speeds. However, it has been widely observed that many applications can tolerate some degree of inaccuracy. This is especially true for exploratory queries on data, where users are satisfied with "close-enough" answers if they can come quickly. A popular technique for speeding up queries at the cost of accuracy is to execute each query on a sample of data, rather than the whole dataset. To ensure that the returned result is not too inaccurate, past work on approximate query processing has used statistical techniques to estimate "error bars" on returned results. However, existing work in the sampling-based approximate query processing (S-AQP) community has not validated whether these techniques actually generate accurate error bars for real query workloads. In fact, we find that error bar estimation often fails on real world production workloads. Fortunately, it is possible to quickly and accurately diagnose the failure of error estimation for a query. In this paper, we show that it is possible to implement a query approximation pipeline that produces approximate answers and reliable error bars at interactive speeds., National Science Foundation (U.S.) (CISE Expeditions Award CCF-1139158), Lawrence Berkeley National Laboratory (Award 7076018), United States. Defense Advanced Research Projects Agency (XData Award FA8750-12-2-0331), Amazon.com (Firm), Google (Firm), SAP Corporation, Thomas and Stacey Siebel Foundation, Apple Computer, Inc., Cisco Systems, Inc., Cloudera, Inc., EMC Corporation, Ericsson, Inc., Facebook (Firm)

Humans' interactions with each other or with socially competent machines exhibit lawful coordination patterns at multiple levels of description. According to Coordination Dynamics, such laws specify the flow of coordination states produced by functional synergies of elements (e.g., cells, body parts, brain areas, people…) that are temporarily organized as single, coherent units. These coordinative structures or synergies may be mathematically characterized as informationally coupled self-organizing dynamical systems (Coordination Dynamics). In this paper, we start from a simple foundation, an elemental model system for social interactions, whose behavior has been captured in the Haken-Kelso-Bunz (HKB) model. We follow a tried and tested scientific method that tightly interweaves experimental neurobehavioral studies and mathematical models. We use this method to further develop a body of empirical research that advances the theory toward more generalized forms. In concordance with this interdisciplinary spirit, the present paper is written both as an overview of relevant advances and as an introduction to its mathematical underpinnings. We demonstrate HKB's evolution in the context of social coordination along several directions, with its applicability growing to increasingly complex scenarios. In particular, we show that accommodating for symmetry breaking in intrinsic dynamics and coupling, multiscale generalization and adaptation are principal evolutions. We conclude that a general framework for social coordination dynamics is on the horizon, in which models support experiments with hypothesis generation and mechanistic insights.

Cerebral aneurysm is a cerebrovascular disorder caused by a weakness in the wall of an artery or vein, which causes a localized dilation or ballooning of the blood vessel. It is life-threatening; hence, an early and accurate diagnosis would be a great aid to medical professionals in making the correct choice of treatment. HemeLB is a massively parallel Lattice-Boltzmann simulation software, which is designed to provide the radiologist with estimates of flow rates, pressures, and shear stresses throughout the relevant vascular structures, intended to eventually permit greater precision in the choice of therapeutic intervention. However, in order to allow surgeries and doctors to view and visualize the results in real-time at medical environments, a cost-efficient, practical platform is needed. In this article, we have developed and evaluated a version of HemeLB on various heterogeneous system-on-chip platforms, allowing users to run HemeLB on a low-cost embedded platform and to visualize the simulation results in real-time. A comprehensive evaluation of implementation on the Zynq SoC and Jetson TX1 embedded graphic processing unit platforms are reported. The achieved results show that the proposed Jetson TX1 implementation outperforms the Zynq implementation by a factor of 19 in terms of site updates per second. 2007-2012 IEEE. Manuscript received February 19, 2019; revised September 20, 2019; accepted November 4, 2019. Date of publication December 2, 2019; date of current version June 3, 2020. This paper was supported by the National Priorities Research Program (NPRP) under Grant 5-792-2-328 from the Qatar National Research Fund (a member of Qatar Foundation). X. Zhai is partially supported by the UK Engineering and Physical Sciences Research Council under Grants EP/R02572X/1 and EP/P017487/1. (Corresponding author: Xiaojun Zhai.) X. Zhai is with the School of Computer Science and Electronic Engineering, University of Essex, CO4 3SQ Colchester, U.K. (e-mail: xzhai@essex.ac.uk). Scopus

In this paper, a 2 GHz LC-VCO with neural network (Multilayer Perceptron) has been designed in a 0.13 ţm CMOS technology. With the integrated neural network, the linearity and tuning range of the LC-VCO has been substantially improved. Compared to a conventional VCO design, the proposed technique can improve the linearity by selecting optimized bias voltages obtained from the output of the neuron network. The result shows that the tuning nonlinearity of the proposed VCO is further optimized from 0.335% to 0.254%. Published version

Motor current signature analysis is the reference method for the diagnosis of induction machines. However, it features some drawbacks, as it is bound to steady-state conditions, and fault signatures may be created by different overlapping phenomena. This paper presents a full-time domain-based method for the quantitative evaluation of electrical faults in induction machines. It relies on stator current measurements; thus, it is compliant with switching power converter drives, provided that a proper current measurement technique is available. Moreover, it allows an accurate quantification of faults without requiring spectrum analysis; hence, it achieves high resolution even with a low time acquisition period. A fault index is computed as the energy of the signal in a suitable ldquofault bandwidth,rdquo thus reducing the effects of frequency variations. The aforementioned advantages are perfectly suited to time varying signals and to embedded drive diagnostic systems.

Curved shell plates used for ship hull have complicated three-dimensional curved surfaces, especially at the bow and stern. The manufacturing processing of ship curved shell plates have been carried out for many years by the tacit knowledge and experience of skilled workers by using wooden templates, and this processing is heavily dependent on individual skills. Formalization and systematization of this manufacturing process are desired． This paper proposed a system to enable skilled workers to process curved shell plates to the desired shape without using wooden templates. Especially, we analyzed a curvature error evaluation method, which is a previous work, and clarifies that the integral value of the curvature error should be used to determine the heating position at the same level as the skilled worker’s decision-making. In addition, total information system was developed for supporting skilled workers decision-making by using several calculation methods. In the case study, we applied the proposed system to an actual bending curved shell plate process. It was confirmed that the proposed system could provide a satisfactory level of decision-making support of the line heating process in the production field of a shipyard.

Sustainable distric development requires innovative energy use solutions. The aim of this paper is to illustrate the operation of a real energy hub that can satisfy both thermal and electrical demands of a generic user. In particular, a specific case study developed around the smart grid of the University Campus of Savona (Italy), which just completed in 2014, is analysed. The grid includes different cogenerative prime movers and a storage system to manage the thermal load demand. Through a time-dependent thermo-economic hierarchical approach developed by the Authors, the work aims at optimizing the management strategy of the different prime movers to satisfy the energy demand, taking into proper account both the energetic and economic aspects. The analysis was carried out considering two different layouts, with and without a conventional stratified thermal storage, to evaluate the impact of this component in the management of the district.

It is found that nodes in Delay Tolerant Networks (DTN) exhibit stable social attributes similar to those of people. In this paper, an adaptive routing algorithm based on Relation Tree (AR-RT) for DTN is proposed. Each node constructs its own Relation Tree based on the historical encounter frequency, and will adopt different forwarding strategies based on the Relation Tree in the forwarding phase, so as to achieve more targeted forwarding. To further improve the scalability of the algorithm, the source node dynamically controls the initial maximum number of message copies according to its own cache occupancy, which enables the node to make negative feedback to network environment changes. Simulation results show that the AR-RT algorithm proposed in this paper has significant advantages over existing routing algorithms in terms of average delay, average hop count, and message delivery rate.

After reading the reply of Kaufmann et al. (2009) to our paper Global and hemispheric temperatures revisited (Gay et al. 2009), we believe that there are several ideas that should be clarified regarding the trend-stationary description of global and hemispheric temperatures and our arguments on why the cointegration methodology may not be adequate for modeling them. We believe that the strategy chosen by Kaufmann et al. (2009) of comparing insample forecasts is not appropriate for evaluating whether global and hemispheric temperature series are best described as integrated or trend stationary processes. It is important to notice that the issue that is being discussed is not forecast accuracy but the adequacy of the probabilistic models that have been proposed for describing global and hemispheric temperatures. This issue cannot be solved by evaluating forecast performance but by using the relevant tests, such as the ones presented in Gay et al. (2009). Moreover, it is a well known result in time series and forecast literature that the best forecasts are not necessarily produced by the model that best describes the underlying data generating process (Hendry and Clements 2002). For example, it is of common knowledge that the accuracy of forecasts may be improved by using a model in first differences instead of a model in levels, even if the series are I(0) (see, for example, Box and Jenkins 1976; Hendry and Clements 2002). Consequently, this is not an appropriate way for inferring what the data generating process is and therefore, the forecast evaluation presented in Kaufmann et al. (2009) cannot help defining what type of process best describes global and hemispheric temperatures.

In 2019, the National Archives of Korea (NAK) developed a blockchain recordkeeping platform to conduct R&amp, D on recordkeeping approaches. This paper introduces two types of R&amp, D studies that have been conducted thus far. The first is the use of blockchain transaction audit trail technology to ensure the authenticity of audiovisual archives, i.e., the application of blockchain to a new system. The second uses blockchain technology to verify whether the datasets of numerous information systems built by government agencies are managed without forgery or tampering, i.e., the application of blockchain to an existing system. Government work environments globally are rapidly shifting from paper records to digital. However, the traditional recordkeeping methodology has not adequately kept up with these digital changes. Despite the importance of responding to digital changes by incorporating innovative technologies such as blockchain in recordkeeping practices, it is not easy for most archives to invest funds in experiments on future technologies. Owing to the Korean government’s policy of investing in digital transformation, NAK’s blockchain recordkeeping platform has been developed, and several R&amp, D tasks are underway. Hopefully, the findings of this study will be shared with archivists around the world who are focusing on the future of recordkeeping.

Web automation applications are widely used for different purposes such as B2B integration and automated testing of web applications. Most current systems build the automatic web navigation component by using the APIs of conventional browsers. While this approach has its advantages, it suffers performance problems for intensive web automation tasks which require real time responses and/or a high degree of parallelism. In this paper, we outline a set of techniques to build a web navigation component able to efficiently execute web navigation sequences. These techniques detect what elements and scripts of the pages accessed during the navigation sequence are needed for the correct execution of the sequence (and, therefore, must be loaded and executed), and what parts of the pages can be discarded. The tests executed with real web sources show that the optimized navigation sequences run significantly faster and consume significantly less resources.

This paper reports on the different engineering, social and financial challenges behind the building and deploying electric energy monitoring and eco-feedback technology in real-world scenarios, which despite being relevant to the research community are seldom reported in the literature. The objectives of this paper are two-fold: First, discuss the technical and social constraints of real-world deployments. This includes, for example, hardware and software requirements, and issues related to security and intrusiveness of the monitoring solutions. Second, identify and understand the costs associated with developing and deploying such systems. These include hardware costs and consumed energy. To this end, we rely on over five years of experience developing and improving a non-intrusive energy monitoring research platform to enable the deployment of long and short-term studies of eco-feedback technology. During this time, two versions of that platform were deployed in 50 homes for periods that lasted between 6 and 18 consecutive months. By iteratively developing and deploying our sensing and eco-feedback infrastructures, we managed to build upon previous findings and lessons learned to understand how to create, deploy, and maintain such systems. Concurrently, we gained insights regarding what are some of the most relevant costs associated with running such experiments.

This paper proposes an opportunistic multicast scheduling scheme using erasure-correction coding to jointly explore the multicast gain and multiuser diversity. For each transmission, the proposed scheme sends only one copy to all users in the multicast group at a transmission rate determined by a SNR threshold. Analytical framework is developed to establish the optimum selection of the SNR threshold and coding rate for given channel conditions to achieve the best throughput in both cases of full channel knowledge and only partial channel knowledge of the average SNR and fading type. Numerical results show that the proposed scheme outperforms both the worst-user and best-user schemes for a wide range of average SNR and multicast group size. Our study indicates that full channel knowledge is only significantly beneficial at small multicast group size. For a large multicast group, partial channel knowledge is sufficient to closely approach the achievable throughput in the case of full channel knowledge while it can significantly reduce the overhead required for channel information feedback. Further extension of the proposed scheme applied to OFDM system to exploit frequency diversity in a frequency-selective fading environment illustrates that a considerable delay reduction can be achieved with negligible degradation in multicast throughput.

This paper describes an energy harvesting solution for a wireless sensor node based on the watermill principle. This solution has been conceived to be employed for the realization of monitoring infrastructures to be deployed in underground water lines like aqueducts or drainage systems. In particular, this solution has been developed to be employed in a Wireless Sensor Network for the monitoring of the “Bottini” (the ancient medieval aqueduct) running under the streets of the Historic Centre of Siena, Italy. Through the proposed harvesting system the sensor nodes are able to operate autonomously for long spans of time, allowing the real time remote monitoring of critical environmental parameters that are crucial for the preservation of this cultural site. The power generation system includes a waterwheel exploiting the water flow of the aqueduct to drive an electric motor, and a power control system, in order to manage the power accumulation and the energy consumption of the sensor node. The operation of the whole architecture has been tested in laboratory in order to prove the effectiveness of the solution and its possible use in the real scenario.

In the field of modern bidding, electronic bidding leads a new trend of development, convenience and efficiency and other significant advantages effectively promote the reform and innovation of China’s bidding field. Nowadays, most systems require a strong and trusted third party to guarantee the integrity and security of the system. However, with the development of blockchain technology and the rise of privacy protection, researchers has begun to emphasize the core concept of decentralization. This paper introduces a decentralized electronic bidding system based on blockchain and smart contract. The system uses blockchain to replace the traditional database and uses chaincode to process business logic. In data interaction, encryption techniques such as zero-knowledge proof based on graph isomorphism are used to improve privacy protection, which improves the anonymity of participants, the privacy of data transmission, and the traceability and verifiable of data. Compared with other electronic bidding systems, this system is more secure and efficient, and has the nature of anonymous operation, which fully protects the privacy information in the bidding process.

In a distributed system, processes must reach a certain level of synchronization to solve a common problem. The strongest form of synchronization can be reached through consensus: all the processes must agree on a common value that has been proposed by one of them. Consensus is universal in shared memory systems: any type of shared object can be implemented using it. Unfortunately, consensus is impossible to solve using only shared registers when processes can crash. To circumvent this impossibility, one can use stronger objects, for example Test&Set or Compare&Swap. The synchronization power of these objects can be measured using the concept of Consensus Number: the maximum number of processes for which they can solve consensus in a crash-prone system. Bitwise AND, OR and XOR operations are very widely used, but have received little attention in the distributed setting. Because bitwise operations are available in most modern processors, they can constitute a valuable tool for synchronization in distributed systems. It is then natural to consider the level of synchronization that these operations can achieve. This paper introduces shared AND/OR and AND/OR/XOR registers. A shared AND/OR register consists of an array of x bits and offers three atomic operations: AND and OR operations, which take an array of x bits as parameter and change the state of the register by applying the corresponding bitwise operation, and a read operation which returns the content of the array. A shared AND/OR/XOR register additionally offers a XOR operation. We show that shared AND/OR registers of x bits have consensus number lfloor (x+1)/2 rfloor, by presenting an algorithm that solves consensus using these registers, and by proving that consensus cannot be solved for n processes using AND/OR registers that have strictly less than 2n-1 bits. We then show that shared AND/OR/XOR registers of x bits have consensus number x using a similar technique.

In this paper we visually explore the data structure of two different visual platforms: the database behind the social environment of a social networking site, and the intricate infrastructure of a research institute for preservation of deposited datasets. We argue that visual analytics of metadata of collections can be used in multiple ways: for the backend users, to inform the archive about structure and growth of its collection; to foster collection strategies; and to check metadata consistency, for the end-users, to give an overview to the collections, and thus to generate more awareness of the collection and its metadata, to give the enduser extra information to contextualize the entirety of the archive. We conclude with a discussion on how text based search combined with different type of visually enhanced browsing improves data access, navigation, and reuse in these two radically different contexts.

In Scrum, we measure performance using velocity. However, the velocity of one team cannot be compared to the velocity of another, since it is a relative measure that is only of meaning to the team using it. So can we objectively measure the performance of teams? Measuring Value Added Time as a percentage of Total Time is a metric that is used in Lean Manufacturing to help get a better understanding of production processes and optimize those processes. This paper introduces an adaptation of this metric to the Agile environment. Giving teams an objective insight into their efficiency helps them optimize their efficiency and compare themselves to other teams. This adapted metric is called Process Efficiency and is comparable across teams, technologies, and domains of practice.

Embeddings of medical concepts such as medication, procedure and diagnosis codes in Electronic Medical Records (EMRs) are central to healthcare analytics. Previous work on medical concept embedding takes medical concepts and EMRs as words and documents respectively. Nevertheless, such models miss out the temporal nature of EMR data. On the one hand, two consecutive medical concepts do not indicate they are temporally close, but the correlations between them can be revealed by the time gap. On the other hand, the temporal scopes of medical concepts often vary greatly (e.g., \textit{common cold} and \textit{diabetes}). In this paper, we propose to incorporate the temporal information to embed medical codes. Based on the Continuous Bag-of-Words model, we employ the attention mechanism to learn a "soft" time-aware context window for each medical concept. Experiments on public and proprietary datasets through clustering and nearest neighbour search tasks demonstrate the effectiveness of our model, showing that it outperforms five state-of-the-art baselines., 7 pages. IJCAI-ECAI-2018

Mobile Ad hoc NETwork is a collection of mobile nodes connected with each other without any centralized infrastructure support. In MANET, every node acts as a router, thereby forwards the packet to other nodes through the best route possible. The cooperation of all other nodes is very essential for a node to transfer data to its desired destination. Throughput is a major factor that determines the health of any network including MANET and there can be many reasons that can disrupt the throughput. In this paper we deal with two prime reasons that may reduce the throughput in a MANET. The first reason is that, if a node behaves selfishly and utilizes the path only for forwarding its own packet, then the packets from other nodes will be dropped and the throughput will gradually get reduced. The second reason for reduction in throughput is the phenomenon called fading, which causes signal attenuation. This phenomenon creates path loss temporarily, during which the packet loss increases and the throughput takes a major hit. Removing such nodes from the network on the basis of doubt about its packet forwarding nature and ability will eventually weaken the network strength. Neglecting the original best route will also reduce the quality of the network. Both the cases of selfishness and fading can be normalized by switching over to an alternate path and coming back to the same route after a short period of time. Thereby the quality as well as the quantity of nodes involved in the network can be maintained. In this paper we have also introduced an innovation called helper nodes which will also help in the formation of alternate path and will very well neutralize the ill effects caused due to selfishness and fading.

This paper describes a computer vision system designed to automatically read the displays of digital instrumentation. The system is used in calibration sessions where many measurements have to be made and where we are interested in getting the whole numerical series downloaded on a host computer. Before our system was running, a human operator had to inspect the instruments at the right times (required by the calibration procedure) and to write down all the results. Note that we are speaking of very simple and sometimes old instruments that usually do not provide a digital interface or a removable memory (and if they do, we do not have a standard interface accepted by all the manufacturers). Results show the benefits of this system, obtaining a success rate higher than 99% in display recognition

Fingermarks are highly relevant in criminal investigations for individualization purposes. In some cases, the question in court changes from ‘Who is the source of the fingermarks?’ to ‘How did the fingermark end up on the surface?’. In this paper, we explore the evaluation of fingermarks given activity level propositions by using Bayesian networks. The variables that provide information on activity level questions for fingermarks are identified and their current state of knowledge with regards to fingermarks is discussed. We identified the variables transfer, persistency, recovery, background fingermarks, location of the fingermarks, direction of the fingermarks, the area of friction ridge skin that left the mark and pressure distortions as variables that may provide information on how a fingermark ended up on a surface. Using three case examples, we show how Bayesian networks can be used for the evaluation of fingermarks given activity level propositions.

This paper introduces a fast solution procedure to solve 100-node instances of the time-dependent orienteering problem (TD-OP) within a few seconds of computation time. Orienteering problems occur in logistic situations were an optimal combination of locations needs to be selected and the routing between the selected locations needs to be optimized. In the time-dependent variant, the travel time between two locations depends on the departure time at the first location. Next to a mathematical formulation of the TD-OP, the main contribution of this paper is the design of a fast and effective algorithm to tackle this problem. This algorithm combines the principles of an ant colony system (ACS) with a time-dependent local search procedure equipped with a local evaluation metric. Additionally, realistic benchmark instances with varying size and properties are constructed. The average score gap with the known optimal solution on these test instances is only 1.4% with an average computation time of 0.5 seconds. An extensive sensitivity analysis shows that the performance of the algorithm is insensitive to small changes in its parameter settings. publisher: Elsevier articletitle: A fast solution method for the time-dependent orienteering problem journaltitle: European Journal of Operational Research articlelink: http://dx.doi.org/10.1016/j.ejor.2013.11.038 content_type: article copyright: Copyright © 2013 Elsevier B.V. All rights reserved. ispartof: European Journal of Operational Research vol:236 issue:2 pages:419-432 status: published

International audience; To face fire it is crucial to understand its behaviour in order to maximize fighting means. To achieve this task, the development of a metrological tool is necessary for estimating both geometrical and physical parameters involved in forest fire modelling. A key parameter is to estimate fire positions accurately. In this paper an image processing tool especially dedicated to an accurate extraction of fire from an image is presented. In this work, the clustering on several colour spaces is investigated and it appears that the blue chrominance Cb from the YCbCr colour space is the most appropriate. As a consequence, a new segmentation algorithm dedicated to forest fire applications has been built using first an optimized k-means clustering in the Cb-channel and then some properties of fire pixels in the RGB colour space. Next, the performance of the proposed method is evaluated using three supervised evaluation criteria and then compared to other existing segmentation algorithms in the literature. Finally a conclusion is drawn, assessing the good behaviour of the developed algorithm.