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European Conference on Antennas and Propagation

作者： Tomislav Debogovic Srecko Susac Julien Perruisseau-Carrier Laboratory of Electromagnetics and Acoustics Ecole Polytechnique Federale de Lausanne (EPFL) Department of Wireless Communications Faculty of Electrical Engineering and Computing (FER) Adaptive MicroNano Wave Systems Ecole Polytechnique Federale de Lausanne (EPFL)

ISBN: (纸本)9781467321877

In this work we present a simple reconfigurable reflectarray (RRA) unit cell general topology and implementation, which allows the independent control of the phase and polarization of the reflected electromagnetic wave. The 1-bit phase control (with 180° step) and the polarization selection between two orthogonal linear polarizations is achieved by means of only two switches embedded in the RRA cell, hence very low complexity. The good performance of the cell under oblique incidence is also demonstrated.

关键词： Beamscanning Reflectarray Reconfigurability Polarization control phase control Polarization 1-bit oblique incidence independent control Cells

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Finding Objects with Segmentation Strategy based Multi Robot Exploration in Unknown Environment

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Procedia - Social and Behavioral Sciences 2013年 97卷 580-586页

作者： Reza Arezoumand Syamsiah Mashohor Mohammad Hamiruce Marhaban Intelligent System and Robotics Laboratory Institute of Advanced Technology Universiti Putra Malaysia 43400 Serdang Selangor Malaysia Department of Computer & Communication Systems Faculty of Engineering Universiti Putra Malaysia 43400 Serdang Selangor Malaysia Department of Electrical and Electronic Engineering University Putra Malaysia 43400 Serdang Selangor Malaysia

In this paper we address exploration algorithm in flat experimental environment with colored objects for multi robots system. The aim of exploration in unknown environment is finding target points like mine detection in outdoor environment without any positioning device. Two algorithms were investigated in this paper one is frontier based random search algorithm and the second is efficient algorithm based on segmentation strategy. To improve efficiency, each robot had to go to different regions to avoid cumulating robots in one region. Constructed maps for all four regions could be shared and navigation could be done more effectively. For constructing map robot can use on built range finder sensor or using vision based systems. Also the algorithm using segmentation strategy is using frontier base algorithm for exploring divided area. Both algorithm implemented and analyzed in Player/Stage simulation. The result was compared and showed the efficiency of the designed algorithm based segmentation strategy. In simulation this algorithm is tested with different number of robots to achieve better view of efficiency for proposed algorithm in different type of environment like harsh environment as possibility of losing some robots.

关键词： Multi-robot exploration Flocking Exploration ratio Trajectory prediction

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Sentiment classification in Persian: Introducing a mutual information-based method for feature selection

Sentiment classification in Persian: Introducing a mutual in...

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Iranian Conference on electrical engineering (ICEE)

作者： Ayoub Bagheri Mohamad Saraee Franciska de Jong Intelligent Database Data Mining and Bioinformatics Laboratory Electrical and Computer Engineering Department Isfahan University of Technology Isfahan Iran School of Computing Science and Engineering University of Salford Manchester UK Human Media Interaction University of Twente Enschede Netherlands

With the enormous growth of online reviews in Internet, sentiment analysis has received more and more attention in information retrieval and natural language processing community. Up to now there are very few researches conducted on sentiment analysis for Persian documents. This paper considers the problem of sentiment classification for online customer reviews in Persian language. One of the challenges of Persian language is using of a wide variety of declensional suffixes. Another common problem of Persian text is word spacing. In Persian in addition to white space as interwords space, an intra-word space called pseudo-space separates word's part. One more noticeable challenge in customer reviews in Persian language is that of utilizing many informal or colloquial words in text. In this paper we study these challenges by proposing a model for sentiment classification of Persian review documents. The proposed model is based on a lemmatization approach for Persian language and is employed Naive Bayes learning algorithm for classification. Additionally we present a new feature selection method based on the mutual information method to extract the best feature collection from the initial extracted features. Finally we evaluate the performance of the model on a manually gathered collection of cellphone reviews, where the results show the effectiveness of the proposed model.

关键词： Feature extraction Mathematical model Classification algorithms Equations Mutual information Training Data mining

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Darwinian Robotic Swarms for exploration with minimal communication

Darwinian Robotic Swarms for exploration with minimal commun...

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Congress on Evolutionary Computation

作者： Micael S. Couceiro Rui P. Rocha Nuno M. F. Ferreira Patricia A. Vargas Institute of Systems and Robotics University of Coimbra Coimbra Portugal Department of Electrical Engineering Engineering Institute of Coimbra Robo Corporation Coimbra Portugal Robotics Laboratory School of Mathematical and Computer Science Heriot-Watt University Edinburgh UK

ISBN: (纸本)9781479904532

The Robotic Darwinian Particle Swarm Optimization (RDPSO) recently introduced in the literature has the ability to dynamically partition the whole population of robots based on simple “punish-reward” rules. Although this evolutionary algorithm enables the reduction of the amount of required information exchange among robots, a further analysis on the communication complexity of the RDPSO needs to be carried out so as to evaluate its scalability. This paper analyses the architecture of the RDPSO communication system, thus describing the dynamics of the communication data packet structure shared between teammates. Moreover, a set of simple communication rules is also proposed in order to reduce the communication overhead within swarms of robots. Experimental results with teams of 15 real robots show that the proposed methodology reduces the communication overhead, thus improving the scalability and applicability of the RDPSO algorithm.

关键词： Robot kinematics Robot sensing systems Mobile ad hoc networks Complexity theory Spread spectrum communication Force

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Opportunistic Relaying for Two-Way Relay Transmission with Asymmetric Traffic Requirements

Opportunistic Relaying for Two-Way Relay Transmission with A...

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IEEE Vehicular Technology Conference

作者： Xiaodong Ji Wei-Ping Zhu Daniel Massicotte Department of Electrical and Computer Engineering Concordia University Montreal Canada H3G 1M8 Laboratory of Signals and Systems Integration (LSSI) Electrical and Computer Engineering Department Université du Québec à Trois-Rivières Trois-Rivières Canada G9A 5H7

ISBN: (纸本)9781467361866

This paper investigates opportunistic relaying of a half-duplex two-way relay network, where two source users exchange information through a shared amplify-and-forward (AF) relay which is opportunistically selected from a set of candidates. Unlike existing works, in our considered network scenario, the two source users have different target rates. A novel protocol for opportunistic relaying is developed, which adaptively switches between the max-min and the pure-max policies according to the information of system traffic. The performance of the new relaying strategy in terms of the system outage probability is analyzed over Rayleigh fading channels. Simulation results demonstrate that the proposed protocol can implement opportunistic relaying efficiently, and can achieve significant performance gains in terms of the outage probability across all traffics.

关键词： AF Two-Way Relay Transmission Asymmetric Traffic Requirements relaying air feed equipment Traffic relay transmission Bidirectional Relay networks

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Optoelectronic fibres for chemical sensing

Optoelectronic fibres for chemical sensing

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International Symposium on Fibers Interfacing the World 2013

作者： Sorin, Fabien Gumennik, Alexander Stolyarov, Alexander M. Schell, Brent R. Hou, Chong Lestoquoy, Guillaume McDaniel, William Rose, Aimee Joannopoulos, John D. Fink, Yoel Research Laboratory of Electronics Massachusetts Institute of Technology MA01239 United States Institute of Soldier Nanotechnology Massachusetts Institute of Technology MA01239 United States Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology MA01239 United States Department of Physics Massachusetts Institute of Technology MA01239 United States FLIR Systems North BillericaMA01862 United States CH 1015 United States

Optical fibers have been used for remote and/or distributed sensing of chemicals in a variety of configurations. In particular, luminescent-based sensing for hazardous materials has been proposed but several limitations have thus far impaired their performance. Here, we propose an alternative approach that relies on multimaterial optoelectronic fibers to sense low concentrations of liquid peroxide-based explosives (PBE). We demonstrate our detection scheme and show sensitivity below 10 ppb, on par with current state-of-the-art systems. We also discuss how to realize efficient distributed sensing with our approach.

关键词： Optical fibers

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Hypothesis testing framework for active object detection

Hypothesis testing framework for active object detection

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IEEE International Conference on Robotics and Automation (ICRA)

作者： Nikolay Atanasov Bharath Sankaran Jerome Le Ny Thomas Koletschka George J. Pappas Kostas Daniilidis Department of Electrical and Systems Engineering University of Pennsylvania Philadelphia PA USA Computational Learning and Motor Control Laboratory University of Southern California Los Angeles CA USA Department of Electrical Engineering Ecole Polytechnique de Montreal QUE Canada Department of Computer and Information Science University of Pennsylvania Philadelphia PA USA

ISBN: (纸本)9781467356404

One of the central problems in computer vision is the detection of semantically important objects and the estimation of their pose. Most of the work in object detection has been based on single image processing and its performance is limited by occlusions and ambiguity in appearance and geometry. This paper proposes an active approach to object detection by controlling the point of view of a mobile depth camera. When an initial static detection phase identifies an object of interest, several hypotheses are made about its class and orientation. The sensor then plans a sequence of viewpoints, which balances the amount of energy used to move with the chance of identifying the correct hypothesis. We formulate an active M-ary hypothesis testing problem, which includes sensor mobility, and solve it using a point-based approximate POMDP algorithm. The validity of our approach is verified through simulation and experiments with real scenes captured by a kinect sensor. The results suggest a significant improvement over static object detection.

关键词： Vocabulary Feature extraction Mobile communication Object detection Robot sensing systems Planning Optimization

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Using soft computing to define standards of care in glaucoma monitoring

Using soft computing to define standards of care in glaucoma...

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第二届(2013)老年人口与健康产业国际会议

作者： M.Ulieru A.C.S.Crichton M Rizzi C.Karanicolas Emergent Information Systems Laboratory Department of Electrical and Computer EngineeringThe Univer Faculty of Medicine Department of Surgery 2500 University Dr NWT2N 1N4 CalgaryABCanada

A fuzzy knowledge base encapsulating core expert rules for glaucoma follow up is developed and subsequently refined into a standard of care by reconciling several expert *** Learning from Examples (LFE) [1] technique is used in addition to expert interviews to generate fuzzy rules from numerical data,and soft competition defines a fuzzy consensus metrics for the expert ***-based extension of this system into a comprehensive set of e-Health services for the glaucoma community enables,besides wide accessibility of the expert knowledge,continuous improvement of the core rule set (standard of care) with the perspectives of several experts.

关键词： Fuzzy knowledge base Soft competition Consensus analysis Standards of care Glaucoma e-Health

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On the achievable capacity of dual-polarized antenna systems in 3D indoor scenarios

On the achievable capacity of dual-polarized antenna systems...

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IEEE International Conference on Communications in China (ICCC)

作者： Fengxiang Wang Xiang Cheng Liuqing Yang Bo Yu Bingli Jiao School of Electronics Engineering & Computer Science Peking University Beijing China State Key Laboratory of Management and Control for Complex Systems Institute of Automation Chinese Academy of Sciences Beijing China Department of Electrical and Computer Engineering Colorado State University Fort Collins CO USA

Unlike triple-polarized antennas, dual-polarized antennas can be easily implemented into thickness limited devices and thus have received much attention recently. Dual-polarized antennas have the potential to double the channel capacity in comparison with an omnidirectional single-input single-output (SISO) system. However, in real three-dimensional (3D) scenarios, dual-polarized antennas cannot capture the arriving power from the third polarization direction, which is orthogonal to the two-dimensional (2D) polarization plane. This will lead to power loss, which may significantly affect the resultant channel capacity. By proposing a novel two-sphere single-bounced geometry-based stochastic model (GBSM) and rigorously analyzing the change of polarization after single-bounced scattering, this paper studies the impact of the power loss on the channel capacity and specifies the conditions under which the channel capacity of dual-polarized systems is even worse than that of omnidirectional SISO systems. Not only that this is the first endeavor on this subject, but also this work is of practical importance in guiding appropriate deployment of dual-polarized antennas in real 3D indoor scenarios.

关键词： Three-dimensional displays Antennas Channel capacity Vectors Signal to noise ratio Correlation Azimuth

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Unsupervised activity clustering to estimate energy expenditure with a single body sensor

Unsupervised activity clustering to estimate energy expendit...

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International Workshop on Wearable and Implantable Body Sensor Networks (BSN)

作者： Shanshan Chen John Lach Oliver Amft Marco Altini Julien Penders Charles L. Brown Department of Electrical & Computer Engineering University of Virginia Charlottesville USA ACT Laboratory Signal Processing Systems Eindhoven University of Technology Eindhoven Netherlands IMEC Netherlands Eindhoven Netherlands

ISBN: (纸本)9781479903313

Body sensor networks (BSNs) have provided the opportunity to monitor energy expenditure (EE) in daily life and with that information help reduce sedentary behavior and ultimately improve human health. Current approaches for EE estimation using BSNs require tedious annotation of activity types and multiple body sensor nodes during data collection and high accuracy activity classifiers during post processing. These drawbacks impede deploying this technology in daily life — the primary motivation of using BSNs to monitor EE. With the goal of achieving the highest EE estimation accuracy with the least invasiveness and data collection effort, this paper presents an unsupervised, single-node solution for data collection and activity clustering. Motivated by a previous finding that clusters of similar activities tend to have similar regression models for estimating EE, we apply unsupervised clustering to implicitly group activities with homogeneous features and generate specific regression models for each activity cluster without requiring manual annotation. The framework therefore does not require specific activity classification, hence eliminating activity type labels. With leave-one-subject-out cross-validation across 10 subjects, an RMSE of 0.96 kcal/min was achieved, which is comparable to the activity-specific model and improves upon a single regression model.

关键词： Feature extraction Data collection Accuracy Estimation Electrocardiography Accelerometers Heart rate

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