ppxscal/embedding_network huggingface dataset:
Numerical and symbolic computation of the lambert w function in c(n x n)
Authors: Hui Ding
Venue:  (2009)

The Lambert W function is a multivalued complex function, first named in the computer algebra system Maple. It has been an important mathematical object. We present iterative schemes and strategies for the numerical evaluation of all branches of the complex Lambert W function with high hardware precision and computational efficiency, and present a set of rules for simplification of its numerical and symbolic expressions. We also extend the numerical and symbolic computations to the Lambert W function in Cn&times;n , for n > 1. In order to implement high precision and computational efficiency, we propose a series of high order and classical iterative methods and strategies. We then construct iterative schemes for the evaluation of the complex Lambert W function in floating point model. Furthermore, simplification is an important research topic for high precision computing in a computer algebra system. We also study some typical classes of simplifications for the Lambert W function in numerical and symbolic cases and give rules for their application. We also consider the solutions to the matrix equation S exp(S) = A as an extension of the Lambert W function to Cn&times;n . The solutions of these matrix equations are not only matrix functions W(A); other solutions also exist. We focus on solving the matrix equation in Cn&times;n , and implement solutions of three by three matrices in the floating-point case, the exact numerical case and the symbolic case, respectively, using the computer algebra system Maple. Keywords. Lambert W function, delay differential equations, functions of matrices, Schur decomposition, Jordan decomposition, computer algebra. 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
The production scheduling problem in a multi-page invoice printing system
Authors: Yan Zhang, Zhili Zhou, Jiyin Liu
Venue: Computers and Operations Research (2010)

This paper addresses the production scheduling problem in a multi-page invoice printing system. The system comprises three stages: the stencil preparation stage, the page printing stage and the invoice assembly stage. Since each page can be considered as a component and the invoice as the finished product, the production system for multi-page invoices can be treated as an assembly-type flowshop with parallel machines at the last two stages. Moreover, two types of sequence-dependent setup operations are considered at the second stage. The objective is to minimize the makespan for all the invoice orders. We first formulate this problem into a mixed-integer linear programming (MILP). Then a hybrid genetic algorithm (HGA) is proposed for solving it due to its NP-hardness. To evaluate the performance of the HGA heuristic, a lower bound for the makespan is developed. Numerical experiment indicates that our algorithm can solve the problem efficiently and effectively.
ANN-based GA for generating the sizing curve of stand-alone photovoltaic systems
Authors: Adel Mellit
Venue: Advances in Engineering Software (2010)

Recent advances in artificial intelligence techniques have allowed the application of such technologies in real engineering problems. In this paper, an artificial neural network-based genetic algorithm (ANN-GA) model was developed for generating the sizing curve of stand-alone photovoltaic (SAPV) systems. Due to the high computing time needed for generating the sizing curves and complex architecture of the neural networks, the genetic algorithm is used in order to find the optimal architecture of the ANN (number of hidden layers and the number of neurons within each hidden layer). Firstly, a numerical method is used for generating the sizing curves for different loss of load probability (LLP) corresponding to 40 sites located in Algeria. The inputs of ANN-GA are the geographical coordinates and the LLP while the output is the sizing curve represented by C"A=f(C"S) (i.e., 30-points were taken from each sizing curve). Subsequently, the proposed ANN-GA model has been trained by using a set of 36 sites, whereas data for 4 sites (randomly selected) which are not included in the training dataset have been used for testing the ANN-GA model. The results obtained are compared and tested with those of the numerical method in order to show the effectiveness of the proposed approach.
On algorithms for the tricriteria shortest path problem with two bottleneck objective functions
Authors: Leizer Lima Pinto, Marta M. B. Pascoal
Venue: Computers and Operations Research (2010)

This paper addresses a tricriteria path problem involving two bottleneck objective functions and a cost. It presents an enhanced method that computes shortest paths in subnetworks, obtained by restricting the set of arcs according to the bottleneck values in order to find the minimal complete set of Pareto-optimal solutions, and taking into account the objective values of the determined shortest paths to reduce the number of considered subnetworks, and thus the number of solved shortest path problems. A labeling procedure for the problem is also developed. The algorithms are compared with the previous literature. Moreover a variant of the first method is presented. Its aim is to choose the solutions with the best bottleneck value when the cost is the same. Results for random instances reveal that the enhanced method is the fastest, and that, in average, it runs in less than 20s for networks with 30000 nodes, an average degree of 20 and 1000 distinct bottleneck values. Its variant that avoids ties improved the former version up to 15% for costs in [1,10].
Mixed succession rules: The commutative case
Authors: Silvia Bacchelli, Luca Ferrari, Renzo Pinzani, Renzo Sprugnoli
Venue: Journal of Combinatorial Theory Series A (2010)

We begin a systematic study of the enumerative combinatorics of mixed succession rules, i.e. succession rules such that, in the associated generating tree, nodes are allowed to produce sons at several different levels according to different production rules. Here we deal with a specific case, namely that of two different production rules whose rule operators commute. In this situation, we are able to give a general formula expressing the sequence associated with the mixed succession rule in terms of the sequences associated with the component production rules. We end by providing examples illustrating our approach.
Development of audit system for intellectual property management excellence
Authors: Tak-Wing Liu, Kwai-Sang Chin
Venue: Expert Systems with Applications: An International Journal (2010)

Intellectual property (IP) management has been widely accepted as an important topic to support the technological innovation. In order to effectively and efficiently implement IP management, it is more practical to firstly focus on the most important aspects which, in turn, provide immediate beneficial results to allow organizations to further implementing other aspects by allocating more resources. The authors propose an IP management excellence audit system that breaks down the complicated IP management practices into a list of enabling criteria and the IP management performance in various criteria can be measured in details. The enabling criteria are the critical success factors to good IP management system and practice. Analytic hierarchy process approach is used to determine the relative importance among the identified criteria in the IP management excellence audit system. The evidential reasoning approach is adopted to develop an expert assessment tool to carry out the audit of organizations' performance in IP management. Based on the audit results, organizations will know the strength and weakness of their current IP management practice and can allocate resources and efforts in priority area for improvement. The authors have validated the developed system and tool in HK-Guangdong (HK-GD) based manufacturing organizations with satisfactory outcome. The audit results are helpful to provide top management facts and information to develop action plans for improving IP management. This paper presents the proposed IP audit system and the industrial case study with the development of an expert assessment tool.
Span-reachability and observability of bilinear hybrid systems
Authors: Mihály Petreczky, Jan H. van Schuppen
Venue: Automatica (Journal of IFAC) (2010)

The paper presents an algebraic characterization of observability and span-reachability of bilinear hybrid systems without guards, i.e. hybrid systems whose continuous dynamics are determined by bilinear control systems, and whose discrete transitions are triggered externally. The proposed characterization provides necessary and sufficient conditions for observability and span-reachability in terms of rank conditions for generalized observability and controllability matrices. This characterization is useful for the system theory of bilinear hybrid systems, in particular, it is used in the realization theory of bilinear hybrid systems, (Petreczky, 2006).
Treephyler
Authors: Fabian Schreiber, Peter Gumrich, Rolf Daniel, Peter Meinicke
Venue: Bioinformatics (2010)

Summary: Assessment of phylogenetic diversity is a key element to the analysis of microbial communities. Tools are needed to handle next-generation sequencing data and to cope with the computational complexity of large-scale studies. Here, we present Treephyler, a tool for fast taxonomic profiling of metagenomes. Treephyler was evaluated on real metagenome to assess its performance in comparison to previous approaches for taxonomic profiling. Results indicate that Treephyler is in terms of speed and accuracy prepared for next-generation sequencing techniques and large-scale analysis. Availability:Treephyler is implemented in Perl; it is portable to all platforms and applicable to both nucleotide and protein input data. Treephyler is freely available for download at http://www.gobics.de/fabian/treephyler.php Contact: fschrei@gwdg.de 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
Application of fuzzy mathematical programming approach to the production allocation and distribution supply chain network problem
Authors: Bilge Bilgen
Venue: Expert Systems with Applications: An International Journal (2010)

An efficient integration of production and distribution plans into a unified framework is critical to achieving competitive advantage. This paper addresses the production and distribution planning problem in a supply chain system that involves the allocation of production volumes among the different production lines in the manufacturing plants, and the delivery of the products to the distribution centers. An integrated optimization model for production and distribution planning is proposed, with the aimed of optimally coordinating important and interrelated logistics decisions. However, a real supply chain operates in a highly dynamic and uncertain environment. Therefore, this model is transformed into fuzzy models taking into account the fuzziness in the capacity constraints, and the aspiration level of costs using different aggregation operators. The applicability and flexibility of the proposed models are illustrated through a case study in consumer goods industry.
Convergence analysis of a variant of the Newton method for solving nonlinear equations
Authors: Yiqin Lin, Liang Bao, Xianzheng Jia
Venue: Computers Mathematics with Applications (2010)

The paper presents a convergence analysis of a modified Newton method for solving nonlinear systems of equations. The convergence results show that this method converges cubically in the nonsingular case, and linearly with the rate 3/8 under some sufficient conditions when the Jacobian is singular at the root. The convergence theory is used to analyze the convergence behavior when the modified Newton method is applied to a nonsymmetric algebraic Riccati equation arising in transport theory. Numerical experiment confirms the theoretical results.
The net-generation interior design student: an exploratory study assessing learning and engagement within a computer simulation environment
Authors: Stephanie Zollinger, Denise Guerin
Venue:  (2009)

The first purpose of this experimental study was to determine if there were effects on achievement between traditional pencil-and-paper instructional strategies and computer simulated instructional strategies used to teach interior design business ethics. The second purpose was to determine the level of engagement of interior design students using traditional pencil-and paper instructional strategies compared to computer simulated instructional strategies to learn business ethics. The data offered both quantitative and qualitative evidence of preferred instructional strategies and what characteristics contributed towards level of engagement.Net-generation learners, born between 1982 and 2000, have been exposed to technology their whole lives and have come to expect the integration of various forms of multi-media instructional strategies within the classroom. Many studies have been conducted that integrate and analyze computer simulation and/or gaming with higher education, but research is very limited within the field of interior design.The study included 21 undergraduate interior design students. Analysis was both quantitative and qualitative in nature including descriptive statistics, frequencies, independent sample t-tests, ANCOVA statistical analysis, and questionnaires with both Likert-type and open-ended question formats. Even though statistical results were not found to be significant and were inconclusive, overall results indicated that the computer simulated case studies created an authentic, dynamic, and empowering learning environment that engaged the learners. 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
Modelling and simulation of the conversion of correlated and unbalanced antenna diversity systems
Authors: S. Vasana
Venue: International Journal of Modelling and Simulation (2008)

Due to the increasing interest in mobile/wireless communication, there has been a continuous research in antenna diversity to combat fading. And the model of correlated and unbalanced diversity branches reflects the real-world scenario. The diagonalizer is introduced here before the diversity branches are combined, which can transform the correlated and balanced branches to the uncorrelated and unbalanced ones, and vice versa. This paper assumes a generic model, in which noise and interference components are correlated with a correlation equal to or smaller than the correlation of signal components. Discussions on how to maximize diversity gains are made in various signal and noise conditions, and with different combining methods. Modelling and simulation of a real world example and the performance are shown in the paper for various dual diversity scenarios.
Pattern recognition via projection-based kNN rules
Authors: Ricardo Fraiman, Ana Justel, Marcela Svarc
Venue: Computational Statistics Data Analysis (2010)

A new procedure for pattern recognition is introduced based on the concepts of random projections and nearest neighbors. It can be considered as an improvement of the classical nearest neighbor classification rules. Besides the concept of neighbors, the notion of district, a larger set into which the data will be projected, is introduced. Then a one-dimensional kNN method is applied to the projected data on randomly selected directions. This method, which is more accurate to handle high-dimensional data, has some robustness properties. The procedure is also universally consistent. Moreover, the method is challenged with the Isolet data set where a very high classification score is obtained.
Transport layer rate control protocols for wireless sensor networks: from theory to practice
Authors: Bhaskar Krishnamachari
Venue:  (2009)

Because of limited bandwidth availability and their typical dense, multi-hop deployment, wireless sensor networks have a fundamental need for efficient transport layer rate control. State of the art transport layer rate control protocols in wireless sensor networks are primarily heuristics that rely on Additive Increase Multiplicative Decrease (AIMD) mechanisms. This heuristic-based design of state of the art rate control protocols raises two key issues: first, due to the AIMD based mechanism the protocols suffer from long convergence times and large end-to-end packet delays; second, existing protocols are monolithic in design, either focusing purely on congestion control functionality without regard for rate utility optimization, or trying to optimize for a specific rate utility function. We improve upon the state of the art by proposing two rate control protocols that address the above issues. To address the issue of long convergence times and large end-to-end packet delays, we propose the Wireless Rate Control Protocol (WRCP). To address the issue of monolithic protocol design, we propose the Backpressure-based Rate Control Protocol (BRCP). WRCP, to our knowledge, is the first explicit and precise rate control protocol for wireless sensor networks. WRCP has been designed using a novel interference model, called the receiver capacity model. The model helps determine the exact available capacity at each receiver in the network. WRCP uses the available capacity information presented by the model, and distributes this capacity amongst contending flows in a neighborhood in order to achieve a lexicographic max-min fair rate allocation. The use of explicit capacity information allows WRCP to exhibit fast convergence time. The explicit capacity information also allows WRCP to operate within the capacity region, resulting in small end-to-end delays. BRCP is a, novel, flexible rate control protocol that has the ability to optimize for any concave rate-utility function. The design of BRCP is achieved by applying Lyapunov drift based stochastic optimization techniques to a Carrier Sense Medium Access (CSMA) based MAC. The ability of BRCP to make rate control decisions purely on local queue information makes it extremely useful in a wireless sensor network, since it requires minimal control information exchange. 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
Modeling the relative strength of security protocols
Authors: Clifford B. Neuman
Venue:  (2009)

This dissertation addresses a problem associated with the relative strength analysis and comparison of security protocols that use cryptographic primitives. The problem relates to the relativism of strength relations under different assumptions, where the goal is to develop comparison methods for non-quantifiable abstract properties associated with security systems. We address the problem by developing a lattice-theoretic model for the analysis of the relative strength of security protocols. In this dissertation, we describe a model where certain known rankings in several dimensions are used to model a range of systems using a Hasse diagram. Then, we come up with the relative strength of security protocols that go beyond the known, but which are generally accepted to be the case. We show how the dimensions and environment allow one to make a statement regarding the relative strengths of the two systems under a particular set of assumptions. 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
Haptic experience and the design of drawing interfaces
Authors: Suziah Sulaiman, Ann Blandford, Paul Cairns
Venue: Interacting with Computers (2010)

Haptic feedback has the potential to enhance users' sense of being engaged and creative in their artwork. Current work on providing haptic feedback in computer-based drawing applications has focused mainly on the realism of the haptic sensation rather than the users' experience of that sensation in the context of their creative work. We present a study that focuses on user experience of three haptic drawing interfaces. These interfaces were based on two different haptic metaphors, one of which mimicked familiar drawing tools (such as pen, pencil or crayon on smooth or rough paper) and the other of which drew on abstract descriptors of haptic experience (roughness, stickiness, scratchiness and smoothness). It was found that users valued having control over the haptic sensation; that each metaphor was preferred by approximately half of the participants; and that the real world metaphor interface was considered more helpful than the abstract one, whereas the abstract interface was considered to better support creativity. This suggests that future interfaces for artistic work should have user-modifiable interaction styles for controlling the haptic sensation.
An improved prediction-correction method for monotone variational inequalities with separable operators
Authors: M. H. Xu, J. L. Jiang, B. Li, B. Xu
Venue: Computers Mathematics with Applications (2010)

In this paper we study the variational inequality problems with a particular splitting structure, in which the mapping F does not have an explicit form and only its function values can be employed in the numerical methods for solving such problems. Studies and applications of such problems can be found in Fukushima (1992) [3], Glowinski (1984) [4], Glowinski (1989) [5] and Xu (2007) [15]. The paper He et al. (2006) [6] presents an efficient prediction-correction method for such problems. Based on the predictor method in the latter, this paper presents two classes of correction methods which are more convenient to be carried out than that in this reference. Numerical experiments show that the new method is effective.
Adaptive bandwidth management and QoS provisioning in IPVPNs
Authors: C. Hota, S. Jha, G. Raghurama
Venue: International Journal of Computers and Applications (2008)

An IP Virtual Private Network (VPN) uses a major share of physical resources of a network to satisfy customer's demand for secure connectivity and Quality of Service (QoS) over the Internet. Service Level Agreements (SLAs) are often used to provide bandwidth-guaranteed VPNs on networks that do not support reservation. To meet these SLAs, service providers overprovision the bandwidth allocation. This is effective, but not economic and does not enforce compliance by the customer, with potentially adverse consequences for charging and congestion control mechanisms. This article proposes an agent-based approach to dynamically adjust the allocated bandwidth as per the user's requests so that the VPNs that are carrying real time or multimedia traffic can be allocated with required amount of bandwidth. The Agent processes acting on behalf of VPN users may decrease their allocated capacity if the users underuse the allocated quota so that the Service provider can satisfy few additional demands. We propose distributed bandwidth resizing algorithms for optimizing inter-VPN and intra-VPN bandwidth allocations. This leads to an increased number of VPN connections and better utilization of network resources. The simulation results of the proposed adaptive algorithms show efficient utilization of network bandwidth among the VPN users.