ppxscal/embedding_network huggingface dataset:
Fundamental performance limits of communications systems impaired by impulse noise
Authors: Riccardo Pighi, Michele Franceschini, Gianluigi Ferrari, Riccardo Raheli
Venue: IEEE Transactions on Communications (2009)

In this paper, we investigate the ultimate performance limits, in terms of achievable information rate (IR), of communication systems impaired by impulse noise. We compare single carrier (SC) and multi-carrier (MC) transmission systems employing quadrature amplitude modulation (QAM) formats. More precisely, we consider SC schemes with coded modulations and MC systems based on orthogonal frequency division modulation (OFDM). For the MC schemes, we introduce a theoretically equivalent channel model which makes the computation of the IR feasible. This simple channel model will be referred to as interleaved MC. We show that, in the presence of impulse noise and except for systems operating at very high spectral efficiency, the IR of MC schemes is lower than that of SC schemes. More precisely, use of MC schemes may lead to an unavoidable fundamental loss with respect to SC schemes at typical coding rates, whereas MC schemes are to be preferred for very high coding rates or in uncoded systems. These results hold for additive white Gaussian noise (AWGN) and dispersive channels, either considering plain OFDM or MC schemes employing water-filling and bit-loading algorithms. In order to validate our theoretical results, we also obtain the bit error rate (BER) performance of SC and MC schemes through Monte Carlo simulations. A few trellis-coded modulation (TCM) and low-density parity-check (LDPC)-coded schemes are considered. The obtained SNR loss in the BER curves between the AWGN and impulse noise channels matches well with the corresponding IR gap.
Mobile Internet Application to Geographical Information Services
Authors: Jusuo Zhou, Anliang Ning, Rui Deng, Fanshun Meng
Venue: Proceedings of the 2009 International Conference on Multimedia Information Networking and Security - Volume 02 (2009)

The nearly ubiquitous access to the internet and interactive content of the WWW has made people a powerful means to access, exchange, and process information. Geographic information/data is the most important and costliest part of GIS, and it could become quickly out of date and thus need to be constantly updated. With the rapid evolution of mobile communication technologies (3G, 4G, etc.), feature-packed mobile phones might become the default physical interface for ubiquitous computing applications, providing the foundation for new interaction paradigms to perform real-time data updates and information exchanges without any limit of space and time. The integration of geospatial information and mobile Internet is simultaneity driven by market demands and technologies. Mobile Geographical Information Service extends unlimited information on the Internet and the powerful service functions of GIS to mobile devices users. The wired Internet and the wireless/mobile internet should not be considered to be mutually exclusive, but used in conjunction with one another in a supportive capacity. Supported by 3G data technologies/services, Mobile GI Services create a new channel of business practice, and thousands of potential applications and services. A complete end-to-end mobile GI services solution is described for organizations interested in offering mobile GI services to consumer or business subscribers. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Iterative power pricing for distributed spectrum coordination in DSL
Authors: Yair Noam, Amir Leshem
Venue: IEEE Transactions on Communications (2009)

In this letter we propose a novel distributed technique for dynamic spectrum management of DSL lines. The proposed method generalizes several known techniques, by imposing pricing for use of spectrum. We propose a simple mechanism that allows each line to choose an appropriate pricing function independently of the other lines. Finally, by incorporating a total power constraint, the algorithm is capable of self-correcting an overly ambitious pricing function. We also provide simulated examples based on measured DSL lines.
Smolyak's algorithm: a simple and accurate framework for the analysis of correlated log-normal power-sums
Authors: Marco Di Renzo, Laura Imbriglio, Fabio Graziosi, Fortunato Santucci
Venue: IEEE Communications Letters (2009)

The accurate analysis of Log-Normal power-sums requires the computation of multidimensional integrals with unknown closed-form. Typical approaches to numerically compute them are based on the full tensor-product formula, whose complexity raises exponentially with the number of summands. In this Letter, we propose a different method which is called Smolyak's algorithm. It belongs to the family of numerical integration techniques on sparse grids, and can be used in conjunction with several approximation methods for Log-Normal power-sums. Numerical results will show a complexity reduction greater than 99% without numerical accuracy degradation.
Interactive constrained clustering for patent document set
Authors: Yusuke Sato, Makoto Iwayama
Venue: Proceeding of the 2nd international workshop on Patent information retrieval (2009)

Constrained clustering is attracting attention as a useful way for grouping a data set into intended clusters using users' feedback. We develop an interactive document clustering method by employing constrained clustering in order to group patent documents into some technological categories based on their contents. This method aims to progressively improve the accuracy of clustering to repeat both the assigning of appropriate cluster to documents and applying constrained clustering. We evaluate how many documents our method needs in order to reach an adequate accuracy and which document should be given to accomplish the desired result in fewer assignments. Moreover, by repeating both the assigning and clustering, it comes to the point at which the clustering accuracy is improved by just only the number of documents given true. We propose an approach to predict such a point based on the amount of cluster label changes in the K-Means loop.
A Secure DSDV Routing Protocol for Ad Hoc Mobile Networks
Authors: Jyu-Wei Wang, Hsing-Chung Chen, Yi-Ping Lin
Venue: Proceedings of the 2009 Fifth International Joint Conference on INC, IMS and IDC (2009)

This paper presents a secure destination-sequenced distance-vector routing protocol (SDSDV) for ad hoc mobile wireless networks. The proposed protocol is based on the regular DSDV protocol. Within SDSDV, each node maintains two one-way hash chains about each node in the network. Two additional fields, which we call AL (alteration) field and AC (accumulation) field, are added to each entry of the update packets to carry the hash values. With proper use of the elements of the hash chains, the sequence number and the metric values on a route can be protected from being arbitrarily tampered. In comparison with the secure efficient distance vector (SEAD) protocol previously proposed in the literature provides only lower bound protection on the metrics, SDSDV can provide complete protection.
Flow Byte Sizes Estimation from Simple Random Packet Sampling
Authors: Hai Zhang, Zhuxu Yang, Wenming Guo
Venue: Proceedings of the 2009 Fifth International Joint Conference on INC, IMS and IDC (2009)

The flow byte sizes is an important metric for network measurement. Previous work on estimating the flow size distribution (in bytes) has been focus on improving sampling technique to increase measurement accuracy. In this paper, we present an algorithm of flow byte sizes estimation based on random packet sampling. Our algorithm first obtains a Maximum Likelihood Estimator of flow length using the TCP protocol information. After that the estimation of the flow byte sizes is accomplished through a linear regression model that relies on the flow length information previously obtained. Experimental results show that our approach is effective enough to capture the network traffic characteristics.
Secure Routing and Broadcast Authentication in Heterogeneous Sensor Networks
Authors: Aasma Abid, Mukhtar Hussain, Firdous Kausar
Venue: Proceedings of the 2009 International Conference on Network-Based Information Systems (2009)

Security of sensor network communication architecture relies on its routing scheme. This paper presents a secure routing scheme for heterogeneous sensor networks (HSNs). HSNs have proven to be more secure and scalable as compared to homogeneous sensor networks which are prone to routing attacks due to resource constraints. In our proposed scheme, routing tables are generated with multipath routing. Base station generates inter-cluster routes and cluster head generates intra-cluster routes. This minimizes the computation load on cluster nodes. We also provide light-weight broadcast authentication used for secure routing table generation and data communication; and to reduce communication overhead. Further, proposed scheme introduces security architecture with in routing protocol. The analysis of proposed scheme shows that it is secure against routing attacks and tolerant to compromised nodes.
Hyperbolic RDM for nonlinear valumetric distortions
Authors: Pietro Guccione, Michele Scagliola
Venue: IEEE Transactions on Information Forensics and Security (2009)

Quantization-based watermarking techniques are sensitive to valumetric scaling, a wide class of distortions applied to images and videos, such as contrast change or gamma correction. Several methods have been proposed to counteract valumetric attacks, but the common approach to the problem is to take only the linear ones into account. This paper presents an extension to the rational dither modulation (RDM) data-hiding scheme which provides robustness against nonlinear distortions modelled by a power-law attack. The algorithm makes use of proper mapping of the pixel values from the Cartesian to hyperbolic coordinates. This mapping is able to render the problem similar to the classical RDM scheme, since fixed multiplicative scaling is cancelled out while the exponentiation of a nonlinear distortion is transformed into a gain scaling. The validity of the approach has been confirmed by applying the watermarking scheme to Gaussian host and real images; experimental results confirm its intrinsic invariance against the power-law attack. Finally, it will be shown that under the white Gaussian noise addition, the proposed scheme achieves a good bit-error rate (BER). The measured BER is affected by the properties of the embedding domain, as supported by the theoretical analysis given in this paper.
Design and implementation of power monitoring practice system
Authors: Ping-Huang Wu, Tsung-Han Wu, Chin-Hwa Kuo, Pei-Lin Wu
Venue: Proceedings of the 10th IASTED International Conference on Computers and Advanced Technology in Education (2007)

As a result of advanced technologies in information and networks, power monitoring systems not only benefit efficient power supply, but also instantaneous power control. Furthermore, as computer hardware becomes more popular and software interfaces are more userfriendly, graphic monitoring provides not just traditional control interface which uses simple light signals and buttons to display and control. It can easily display texts, numbers, graphics, and other useful contents. It also raises the add-on values of graphic monitoring systems. We use Microsoft Visual Basic (VB) as the tool to develop graphic monitoring software. Our research, integrating teaching contents, current communication, and computer and control technology, focuses on designs of power monitoring systems.
Memory Built-in Self Test in Multicore Chips with Mesh-Based Networks
Authors: Hsiang-Ning Liu, Yu-Jen Huang, Jin-Fu Li
Venue: IEEE Micro (2009)

Using a packet-based built-in self test for RAM cores in mesh-based networks on chip (NoC) can reduce the BIST circuit's area cost. The proposed scheme reuses the NoC to transport test patterns to RAM such that routing doesn't limit the number of RAM cores tested. The scheme also achieves higher test parallelism than a typical parallel BIST by interleaving the read/write test operations.
Analysis of cognitive radio spectrum access with finite user population
Authors: Eric W. M. Wong, Chuan Heng Foh
Venue: IEEE Communications Letters (2009)

A new loss model for cognitive radio spectrum access with finite user population are presented, and exact solution for the model and its approximation for computation scalability are given. Our model provides the investigation of the delay performance of a cognitive radio system. We study the delay performance of a cognitive radio system under various primary traffic loads and spectrum band allocations.
Strengthen Military Academy's Information Security Management
Authors: Liu Qingguo, Zhang Wei
Venue: Proceedings of the 2009 International Conference on Multimedia Information Networking and Security - Volume 01 (2009)

Information techniques give support to the teaching theory, teaching plans, teaching mode, teaching measures and teaching management. However, problems on information security and its management are increasing. It is of great significance to research into those information security plans and management methods which are suitable for military academy. Based on the situation of military academy's information security management, this thesis analyzes the main problems in current information security management, does some research on the four elements that influence information management, and brings out five countermeasures for enhancing military academy's information security management.
The nature of the discourse in web-based Collaborative Learning Environments: Case studies from four different countries
Authors: M. Veermans, D. Cesareni
Venue: Computers Education (2005)

The present paper describes a series of case studies of collaborative learning supported by two web-based learning environments: Synergeia2 and FLE3. The case studies were conducted in Finland, Greece, Italy, and the Netherlands as a part of international project called Innovative Technologies for Collaborative Learning. The general aim of this investigation was to examine the cases in a detailed way, and to find possible indications that might explain success and difficulties related to implementation of web-based Collaborative Learning Environments. The specific aims of the present study were to investigate the nature of the students' and teachers' computer-mediated discourse, whether and to what extent the students and teachers actually used the knowledge types in Synergeia2 and FLE3-environments (resembling CSILE's thinking types); and finally, to what extent the use of knowledge types was connected to the content of knowledge produced by the students and the teachers. The results showed considerable differences in the nature of the discourse and difficulties in students' labelling of their own notes. It is suggested that the adoption and development of collaborative practices takes time: collaborative learning in web-based environments is best organized around long-lasting learning activities; instead of weeks, whole academic terms. Further, it is underlined that the selection of good sets of knowledge types is important. Software must allow teachers to construct appropriate sets of knowledge types.
Short Communication: Selecting the best statistical distribution-a comment and a suggestion on multi-criterion evaluation
Authors: Ramakrishnan Ramanathan
Venue: Computers and Industrial Engineering (2005)

An interesting new approach for selecting a distribution to describe the observed data has been presented in a paper recently published in Computers and Industrial Engineering. While appreciating the new contribution of the paper, we highlight an important difficulty with their method and suggest that data envelopment analysis (DEA) could be advantageously used to improve the multi-criterion evaluation.
An efficient folded architecture for lifting-based discrete wavelet transform
Authors: Guangming Shi, Weifeng Liu, Li Zhang, Fu Li
Venue: IEEE Transactions on Circuits and Systems II: Express Briefs (2009)

In this brief an efficient folded architecture (EFA) for lifting-based discrete wavelet transform (DWT) is presented. The proposed EFA is based on a novel form of the lifting scheme that is given in this brief. Due to this form, the conventional serial operations of the lifting data flow can be optimized into parallel ones by employing parallel and pipeline techniques. The corresponding optimized architecture (OA) has short critical path latency and is repeatable. Further, utilizing this repeatability, the EFA is derived from the OA by employing the fold technique. For the proposed EFA, hardware utilization achieves 100%, and the number of required registers is reduced. Additionally, the shift-add operation is adopted to optimize the multiplication; thus, the proposed architecture is more suitable for hardware implementation. Performance comparisons and field-programmable gate array (FPGA) implementation results indicate that the proposed EFA possesses better performances in critical path latency, hardware cost, and control complexity.
A utility-based joint power and rate adaptive algorithm in wireless ad hoc networks
Authors: Jialing Zheng, Maode Ma
Venue: IEEE Transactions on Communications (2009)

In this paper, a utility-based joint power and rate adaptive algorithm (UPRA) is proposed to alleviate the influence of channel variation by using softened signal-to-interference-and-noise ratio (SINR) requirements. The transmission power and rate of each user will be adjusted to maximize its own net-utility according to the states of channel, which results in a balance between the effective transmission rate and power consumption. Although the UPRA works based on a non-cooperative game, cooperation among users can be achieved so that the throughput of the whole network will be improved. The convergence of the algorithm has also been studied in both feasible and infeasible cases.
TBSIM: A computer program for conditional simulation of three-dimensional Gaussian random fields via the turning bands method
Authors: Xavier Emery, Christian Lantuéjoul
Venue: Computers Geosciences (2006)

The simulation of spatially correlated Gaussian random fields is widespread in geologic, hydrologic and environmental applications for characterizing the uncertainty about the unsampled values of regionalized attributes. In this respect, the turning bands method has received attention among practitioners, for it allows multidimensional simulations to be generated at the CPU cost of one-dimensional simulations. This work provides and documents a set of computer programs for (i) constructing three-dimensional realizations of stationary and intrinsic Gaussian random fields, (ii) conditioning these realizations to a set of data and (iii) back-transforming the Gaussian values to the original attribute units. Such programs can deal with simulations over large domains and handle anisotropic and nested covariance models. The quality of the proposed programs is examined through an example consisting of a non-conditional simulation of a spherical covariance model. The artifact banding in the simulated maps is shown to be negligible when thousands of lines are used. The main parameters of the univariate and bivariate distributions, as well as their expected ergodic fluctuations, also prove to be accurately reproduced.
Modeling of ultrasonic and acoustic waves propagation through 2D lattice structures
Authors: Ales Michtchenko, James A. Smith, Massimo Ruzzene
Venue: Proceedings of the IASTED Asian Conference on Modelling and Simulation (2007)

Effective non-destructive testing techniques for modern lattice structural materials are in great demand. Amongst the more successful tecniques are ultrasonic and acoustic testing. The focus of this paper is the simulation of wave propagation through 2D lattice structures. This simulation helps to optimize the design of ultrasonic/acoustic testing techniques (e.g. find optimal response and excitation points), as well as outline the boundaries of applicability for the testing. An ultrasonic propagation model for lattices composed of beam structures is developed and implemented in Matlab to obtain a computationally efficient and flexible simulation tool. This paper describes application of the code to the simulation of wave propagation through 2D lattice structures of various geometry. The considerations presented can be applied for the investigation of wave propagation in various complex structural systems, such as honeycombs, panels with periodic reinforcements and other. The code can be extended to simulate propagation in 3D assemblies to cover a wider range of configurations.
Development of Zig System for Evaluating an Oscillator Performance
Authors: Dal Hwan Yoon, Long Chen, Teng Lian, Jong-Hwa Yoon, Jong-Uk Yoon
Venue: Proceedings of the 2009 Fifth International Joint Conference on INC, IMS and IDC (2009)

we have developed the Zig system for the voltage controlled crystal oscillator (VCXO) performance evaluation with positive emitter coupled logic(PECL). The VCXO is a crystal oscillator which includes a varactor diode and associated circuitry allowing the frequency to be changed by application of a voltage across that diode. The characteristics of the PECL has the delay time less than 2 ns and the faster logic gate, and the high level output greater than 2.3 V and the low level output smaller than 1.68 V.
Access Security Based on Bayesian Trust Network
Authors: Yichun Liu
Venue: Proceedings of the 2009 International Conference on Multimedia Information Networking and Security - Volume 02 (2009)

In this paper, a novel access control scheme based on Bayesian trust network is developed to address to the security services in P2P environments. The trust mechanism is constructed with Bayesian network model, which could describe precise trust degree of the P2P node responding to various operation or access. The model of access control is proposes with Bayesian trust network of P2P members, and dynamically manages the access permission according to the Bayesian trust network of subject and object.
Broadcast Authentication Scheme Based on Tornado Code for Wireless Sensor Networks
Authors: Jianmin Zhang, Qingmin Cui, Xiande Liu
Venue: Proceedings of the 2009 International Conference on Multimedia Information Networking and Security - Volume 01 (2009)

Broadcast authentication is an essential security service in wireless sensor networks, as it allows a sender to broadcast messages to multiple nodes in an authenticated way. This paper propose a light-weight, scalable broadcast authentication scheme over a long period of time. Instead of using multi-level key chains as in multilevel µTESLA, the scheme uses multiple short key chains to replace one long key chain in µTESLA. In order to reduce the communication overhead, this scheme uses Tornado codes that encode/decode hash authentication packet. To evaluate the performance of our scheme, we compare our scheme with multilevel µTESLA.
Fast hardware algorithm for division in GF(2m) based on the extended Euclid's algorithm with parallelization of modular reductions
Authors: Katsuki Kobayashi, Naofumi Takagi
Venue: IEEE Transactions on Circuits and Systems II: Express Briefs (2009)

We propose a fast hardware algorithm for division in GF(2m) based on the extended Enclid's algorithm. The algorithm requires only one iteration to perform the operations that correspond to the ones performed in two iterations of previously reported division algorithms. Since the algorithm performs modular reductions in parallel by changing the order of execution of the operations, a circuit based on this algorithm has almost the same critical path delay as the previously proposed ones. The circnit computes division in m clock cycles, whereas the previously proposed circnits take 2m - 1 or more clock cycles.