ppxscal/embedding_network huggingface dataset:
On the marginal distribution of the eigenvalues ofWishart matrices
Authors: Alberto Zanella, Marco Chiani, Moe Z. Win
Venue: IEEE Transactions on Communications (2009)

Random matrices play a crucial role in the design and analysis of multiple-input multiple-output (MIMO) systems. In particular, performance of MIMO systems depends on the statistical properties of a subclass of random matrices known as Wishart when the propagation environment is characterized by Rayleigh or Rician fading. This paper focuses on the stochastic analysis of this class of matrices and proposes a general methodology to evaluate some multiple nested integrals of interest. With this methodology we obtain a closed-form expression for the joint probability density function of k consecutive ordered eigenvalues and, as a special case, the PDF of the lth ordered eigenvalue of Wishart matrices. The distribution of the largest eigenvalue can be used to analyze the performance of MIMO maximal ratio combining systems. The PDF of the smallest eigenvalue can be used for MIMO antenna selection techniques. Finally, the PDF the kth largest eigenvalue finds applications in the performance analysis of MIMO singular value decomposition systems.
A self-synchronizing method for asynchronous code acquisition in band-limited spread spectrum communications
Authors: Francesco Benedetto, Gaetano Giunta
Venue: IEEE Transactions on Communications (2009)

This paper addresses the problem of initial synchronization of pseudo-noise code. A new code acquisition technique for spread-spectrum communication systems using band-limited chip waveforms is presented. Unlike conventional power detector based on testing the estimated maximum of the ambiguity function, the devised detector exploits a fast parabolic interpolation, running on three estimated ambiguity samples in the neighborhood of the coarse estimate. Performance analysis is carried out in comparison with conventional detector. Mathematical expressions for the probability of false alarm and detection are derived. They are numerically evaluated, under operating settings, by a reduced Taylor's expansion up to the second order. The theoretical results, substantiated by computer simulations, have evidenced that the devised method is well suited for asynchronous spread-spectrum communications. In particular, the acquisition performance depends on the actual offset between the received and the reference code waveforms, which are randomly distributed (in chip-asynchronous systems) within one sampling period. In fact, the parabolic interpolation technique outperforms the conventional detector for a wide range of code offsets because it is able to self-synchronize the testing variable around the true offset.
Forming effective worker teams with multi-functional skill requirements
Authors: Erin L. Fitzpatrick, Ronald G. Askin
Venue: Computers and Industrial Engineering (2005)

Throughout much of the past century, manufacturing efficiencies were gained by constructing systems from independently designed and optimized tasks. Recent theories and practice have extolled the virtues of team-based practices that rely on human flexibility and empowerment to improve integrated system performance. The formation of teams requires consideration of innate tendencies and interpersonal skills as well as technical skills. In this project we develop and test mathematical models for formation of effective human teams. Team membership is selected to ensure sufficient breadth and depth of technical skills. In addition, measures of worker conative tendencies are used along with empirical results on desirable team mix to form maximally effective teams. A mathematical programming formulation for the team selection problem is presented. A heuristic solution is proposed and evaluated.
A scenario description language of network attack and defense
Authors: Li Xiao-Jian, Xia Chun-He, Li Li, Wang Hai-Quan
Venue: Proceedings of the IASTED Asian Conference on Modelling and Simulation (2007)

Most simulations and experiments on large-scale computer network security are based on pre-designed scenarios. Computer network attack/defense scenario consists of Computer Network Attack Scenario (CNAS), Computer Network Defense Scenario (CNDS) and Network Environment Configure Scenario (NECS). In this paper, a scenario description language is constructed using Context-Free Grammar (CFG), to describe the planned commands and network environments in exercises and to create corresponding operational commands for network configurations and simulation programs in the security simulation systems. Using the scenario description language, we develop a prototype system on the simulation platform, GTNetS. The experimental results show that the language can describe concepts of attack/defense explicitly and that the system based on the language can accomplish tasks on the simulation platform successfully.
"Split ADC" calibration for all-digital correction of time-interleaved ADC errors
Authors: John A. McNeil, Christopher David, Michael CoIn, Rosa Croughwell
Venue: IEEE Transactions on Circuits and Systems II: Express Briefs (2009)

The "split analog-to-digital converter (ADC)" architecture enables fully digital calibration and correction of offset, gain, and aperture-delay mismatch errors in time-interleaved ADCs. The calibration of M interleaved ADCs requires 2M +1 half-sized ADCs, a minimal increase in analog complexity. Each conversion is performed by a pair of half-sized ADCs, generating two independent outputs that are digitally corrected using estimates of offset, gain, and aperture-delay errors. The ADC outputs are averaged to produce the ADC output code. The difference of the outputs is used in a calibration algorithm that estimates the error in the correction parameters. Any nonzero difference drives a least-mean-square feedback loop toward zero difference, which can only occur when the average error in each correction parameter is zero. A simulation of a 4: 1-time-interleaved 16-bit 12-MSps successive-approximation-register ADC shows calibration convergence within 400 000 samples.
Variational Video Mask Generation
Authors: Zhen-Long Du, Xiao-Li Li
Venue: Proceedings of the 2009 International Conference on Multimedia Information Networking and Security - Volume 02 (2009)

Video mask, which delimits the ROI (Region Of Interest) of frame, is frequently-used in video editing. Direct interpolation often needs the time-consuming manual modification. In this paper, we present a method of mask generation, which formulates the mask generation as a variation problem, and makes the mask field subject to the dual constraints from the video and keyframes. The differential solution can significantly maintain the spatiotemporal coherence.
3GRAINS: 3D Gravity Interpretation Software and its application to density modeling of the hellenic subduction zone
Authors: K. Snopek, U. Casten
Venue: Computers Geosciences (2006)

3GRAINS is a program, which allows interactive modeling of a density structure with respect to given gravity anomalies. It is written in standard C++ with the use of Qt Library. It has been compiled on the Linux platform, but it can be also compiled under the Windows environment. The program uses rectangular prisms to calculate the gravity effect of a model. Blocks used in interpretation can have different size; it is useful to model shallow layers with higher resolution than the deep ones. Gravity stations used in modeling can have arbitrary distribution. The software uses the altitude of the station to compute its anomaly. The gravity effect of each block for each station is calculated once and saved together with the modeled structure. A major objective was to reduce the amount of memory used by the program. Thanks to the applied compression algorithm, high-resolution density structures can be accommodated by an average modern computer. The absolute accuracy of modeled anomalies depends on scaling of the problem. The relative error does not exceed 0.001. A very important characteristic of the software is a simplicity in creating and changing of the models by means of the graphical user interface. The three-dimensional density structure can be browsed in 2D cross-sections on one horizontal and two perpendicular vertical planes. The program offers a number of export options. Numerical models as well as different cross-sections and layer boundaries can be saved to a file for further visualization of the results. As an example a density model of the Hellenic Subduction Zone is presented. The model reflects a very complicated tectonic situation of the region and includes main tectonic units: seawater, sediments, crust and upper mantle. Horizontal density distributions within each unit allow recognition of different types of the lithosphere.
Introduction to IBM's knowledge-systems products
Authors: A. J. Symonds
Venue: IBM Systems Journal (1986)

The industrialization of artificial intelligence is believed by many to be a technology that will contribute to a new generation of "smart" computer systems. Technical managers who are users or suppliers of computer systems are trying to understand how the technology can help them, and they are finding it an elusive subject to grasp. This introductory paper starts with a technology overview that aims to address this need for understanding and provide a suitable background for the papers that follow.
Computer-assisted learning for mathematical problem solving
Authors: Kuo-En Chang, Yao-Ting Sung, Shiu-Feng Lin
Venue: Computers Education (2006)

Previous computer-assisted problem-solving systems have incorporated all the problem-solving steps within a single stage, making it difficult to diagnose stages at which errors occurred when a student encounters difficulties, and imposing a too-high cognitive load on students in their problem solving. This study proposes a computer-assisted system named MathCAL, whose design is based on four problem-solving stages: (1) understanding the problem, (2) making a plan, (3) executing the plan and (4) reviewing the solution. A sample of one hundred and thirty fifth-grade students (aged 11 years old) completed a range of elementary school mathematical problems and empirically demonstrated. The results showed MathCAL to be effective in improving the performance of students with lower problem solving ability. This evaluation allowed us to address the problem of whether the assistances in various stages help students with their problem solving. These assistances improve students' problem-solving skills in each stage.
A comparative analysis of Reference Models for Visual and Computational Integrated Environments
Authors: Rosa Maria Spitaleri, Rossella Cossu
Venue: Computers and Graphics (1997)

In the framework of Visualization in Scientific Computing (ViSC) the definition of reference models appears to be an especially promising research area. In this paper we propose a unified approach to the analysis of reference models based on keyword classification. We analyze several models representing either visualization systems or complex computational and visual processes. We propose grouping the reference models in two sets called Reference Models in Scientific Visualization and Reference Models of Visual Computational Simulations respectively. For each of these two sets we present a general overview of reference models belonging to, we identify the main concepts and keywords characterizing the reference model definitions, and we present the result characterization organized in lists. We propose definitions of the structure of each of the reference model and representative keyword sets. To characterize specific models, and underline either their commonalties or distinctions, we label for instance two- or three-dimensional and one- or multilevel structures. We start to develop a comparative analysis of separate approaches and we identify elements significant for further advances in reference model design.
An Artificial Immune System Model Based on Semantics
Authors: Chu-Jiao Wang, Shi-Xiong Xia, Hai-zhi Wang
Venue: Proceedings of the 2009 Second International Workshop on Computer Science and Engineering - Volume 01 (2009)

With the development of artificial immune technology, People set more and more focus on the diagnosis problem in such complex distribution systems based on artificial immunity. This paper presents an intelligent methodology for diagnosing incipient faults in mine hoist. In this fault diagnosis system, In order to enhance the fault diagnosis performance, we propose a novel ideal of semantic-centered fault diagnosis based on artificial immunity for mine hoist. Concerning with the disadvantage negative selection algorithm can not effectively capture the semantic information in some complex spaces, in the given definition of model-based fault diagnosis, this paper proposes a logic-based semantic model. The model represents lymphocytes and antigens as logic-operator, which can express complex semantics and gain the minimal diagnosis by the theorem provers of first order logic. Finally, in the background of process-based abnormal detection, we designed a systematic framework which tries to exploit semantic information. It proves that this model can effectively solve the semantic problem of diagnosis for mine hoist.
An architecture for interoperable GIS use in a local community environment
Authors: Leonid Stoimenov, Slobodanka Djordjević-Kajan
Venue: Computers Geosciences (2005)

Many organizations in the local community environment use and produce geospatial data. An increasing number of geodata producers and users have expressed the need for the integration of geodata and for interoperable geographic information systems (GIS). Each of these user groups has a different view of the world and available information is always distributed and mostly heterogeneous. Wrappers and mediation may resolve structural and syntactic heterogeneity. However, domain experts use the concepts and terminology specific to their fields of expertise, and use different parameters to express their model of a concept. Such semantic heterogeneity of data sources causes serious problems, which may be resolved by ontologies. The goal of our research is to define an architecture, called GeoNis, for semantic interoperability of distributed and heterogeneous GIS in a local community environment. The proposed architecture is based on mediation and ontologies. GeoNis solution to the problem of semantic heterogeneity is to formally specify the meaning of the terminology of each community using local ontology and to define a translation between each community terminologies and an intermediate terminology represented by top-level ontology and common data model.
Topological conceptual model of geological relative time scale for geoinformation systems
Authors: Janusz Michalak
Venue: Computers Geosciences (2005)

In geological information systems, the methods of encoding geological age, both relative and absolute, play an important role. Interoperable exchange of information between these systems requires application of solutions based upon recognized international standards. The ISO 19108 standard can serve as a basis for elaboration of a conceptual model for geological data, as well as its implementation, for instance in Extensible Markup Language (XML). The nature of the relative geological time scale requires application of topological elements in this model, and the model presented here is a complex construction of such elements. As a result, operations of the interface used for objects belonging to classes derived from the ''TimeTopologicalOrdinalEra'' class may return a value in the form of topological time relations such as: ''Before'', ''After'', ''During'' and ''OverlappedBy''.
Unseen visible watermarking: a novel methodology for auxiliary information delivery via visual contents
Authors: Chun-Hsiang Huang, Shang-Chih Chuang, Yen-Lin Huang, Ja-Ling Wu
Venue: IEEE Transactions on Information Forensics and Security (2009)

A novel data hiding scheme, denoted as unseen visible watermarking (UVW), is proposed. In UVW schemes, hidden information can be embedded covertly and then directly extracted using the human visual system as long as appropriate operations (e.g., gamma correction provided by almost all display devices or changes in viewing angles relative to LCD monitors) are performed. UVW eliminates the requirement of invisible watermarking that specific watermark extractors must be deployed to the receiving end in advance, and it can be integrated with 2-D barcodes to transmit machine-readable information that conventional visible watermarking schemes fail to deliver. We also adopt visual cryptographic techniques to guard the security of hidden information and, at the same time, increase the practical value of visual cryptography. Since UVW can be alternatively viewed as a mechanism for visualizing patterns hidden with least-significant-bit embedding, its security against statistical steganalysis is proved by empirical tests. Limitations and other potential extensions of UVW are also addressed.
Fabric-based active electrode design and fabrication for health monitoring clothing
Authors: Carey R. Merritt, H. Troy Nagle, Edward Grant
Venue: IEEE Transactions on Information Technology in Biomedicine (2009)

In this paper, two versions of fabric-based active electrodes are presented to provide a wearable solution for ECG monitoring clothing. The first version of active electrode involved direct attachment of surface-mountable components to a textile screen-printed circuit using polymer thick film techniques. The second version involved attaching a much smaller, thinner, and less obtrusive interposer containing the active electrode circuitry to a simplified textile circuit. These designs explored techniques for electronic textile interconnection, chip attachment to textiles, and packaging of circuits on textiles for durability. The results from ECG tests indicate that the performance of each active electrode is comparable to commercial Ag/AgCl electrodes. The interposer-based active electrodes survived a five-cycle washing test while maintaining good signal integrity.
On the second order statistics of generalized gamma process
Authors: Serguei Primak, Valeri Kontorovich
Venue: IEEE Transactions on Communications (2009)

The second order statistics, such as the level crossing rate and the average fade duration of a generalized Gamma distribution are derived in this paper. Joint distribution of the process and its derivative and the marginal distribution of the derivative is developed. It is shown that apart from the Nakagami case the velocity of the process is dependent on the value of the process. The results are applied to derive some characteristics of error flow in channels with dual mobility, generalized Gamma fading and basic modulations.
The Automatic Fuzzy Fingerprint Vault Based on Geometric Hashing: Vulnerability Analysis and Security Enhancement
Authors: Xiao Qiao Guo, Ai Qun Hu
Venue: Proceedings of the 2009 International Conference on Multimedia Information Networking and Security - Volume 01 (2009)

Fuzzy fingerprint vault is a developed cryptographic construct to secure critical data with the fingerprint data. The geometric hashing technique is proposed to realize an important feature, pre-alignment, but it yields great vulnerabilities to the system. In this paper, we discuss the details of the implementation of the fuzzy fingerprint vault based on geometric hashing, and then illustrate the vulnerability along with a potential cracking algorithm. Finally we propose a modified fuzzy fingerprint vault scheme with enhanced security and provide the simulation results of our method.
The application of geostatistics in defining the characteristic distance for grain size trend analysis
Authors: E. Poizot, Y. Mear, M. Thomas, S. Garnaud
Venue: Computers Geosciences (2006)

Sediment trend analysis is a widely used tool in coastal management. The Gao and Collins method is used mostly in complex open marine environments. A key component of this method is the notion of a characteristic distance known as D"c"r. Geostatistics are used to improve the determination of this parameter. A new distance called D"g is proposed through the analysis of the semi-variogram. A comparison between D"c"r and D"g was performed by numerous tests upon regular/irregular and filtered/non-filtered sets of sedimentological data. Compared to tracer results, regular and non-filtered data are considered to be the best descriptor for sediment trend patterns. Using 260 sedimentological samples from the southern Bay of Seine (English Channel), an application of this approach allows us to gain a better understanding of the superficial sediment transport pathways between the Seine estuary and narrow shallow water area north of the Calvados coast.
Power efficient back-off reduction through polyphase filtering magnitude modulation
Authors: Marco Gomes, Vitor Silva, Francisco Cercas, Martin Tomlinson
Venue: IEEE Communications Letters (2009)

A multistage polyphase magnitude modulation (MPMM) technique is proposed for single carrier (SC) modulations, to efficiently reduce the peak-to-average power ratio (PAPR) of the bandwidth limited signal resulting from root-raised cosine (RRC) filtering. We show that the application of back-off to the transmitter high-power amplifier (HPA), in order to avoid nonlinear distortion and thus spectral regrowth, can be almost eliminated, even at very low roll-off values, leading to system's high power efficiency. We also show that noise sensitivity due to MPMM is considerably minimized by improving the initial receiver's soft-decoding estimates, based on the average positions of the MPMM constellation symbols.
An information-theoretic view of network-aware malware attacks
Authors: Zesheng Chen, Chuanyi Ji
Venue: IEEE Transactions on Information Forensics and Security (2009)

This work provides an information-theoretic view to better understand the relationships between aggregated vulnerability information viewed by attackers and a class of randomized epidemic scanning algorithms. In particular, this work investigates three aspects: 1) a network vulnerability as the nonuniform vulnerable-host distribution, 2) threats, i.e., intelligent malwares that exploit such a vulnerability, and 3) defense, i.e., challenges for fighting the threats. We first study five large data sets and observe consistent clustered vulnerable-host distributions. We then present a new metric, referred to as the nonuniformity factor, that quantifies the unevenness of a vulnerable-host distribution. This metric is essentially the Renyi information entropy that unifies the nonuniformity of a vulnerable-host distribution with different malware-scanning methods. Next, we draw a relationship between Renyi entropies and randomized epidemic scanning algorithms. We find that the infection rates of malware-scanning methods are characterized by the Renyi entropies that relate to the information bits in a nonunform vulnerable-host distribution extracted by a randomized scanning algorithm. Meanwhile, we show that a representative network-aware malware can increase the spreading speed by exactly or nearly a nonuniformity factor when compared to a random-scanning malware at an early stage of malware propagation. This quantifies that how much more rapidly the Internet can be infected at the early stage when a malware exploits an uneven vulnerable-host distribution as a network-wide vulnerability. Furthermore, we analyze the effectiveness of defense strategies on the spread of network-aware malwares. Our results demonstrate that counteracting network-aware malwares is a significant challenge for the strategies that include host-based defenses and IPv6.