ppxscal/embedding_network huggingface dataset:
Redesigning network topology with technology considerations
Authors: Sami J. Habib
Venue: International Journal of Network Management (2008)

We present a redesign methodology that automatically redesigns a network topology while considering the different network technology interfaces. The network redesign problem is to preserve as many as possible of the network devices within the original network topology to satisfy the redesign factors while minimizing the redesign cost and time. The redesign factors can be various parameters that are involved in the design of a network topology, such as the workload and number of clients. In this paper we used a uniform growth of the network workload as the main factor for topology redesign; moreover, our methodology attempts to maintain as many as possible of the network devices within the original topology while satisfying the extra growth of the clients' loads. We formulated the network redesign problem as an optimization problem and used an evolutionary approach to search the redesign space. The experimental results for a three-level network redesign problem described here demonstrate how valuable the redesign methodology is in finding good solutions with low redesign cost and short redesign time for an enterprise networks consisting of 65 client nodes.
A Multi-Purpose Wireless Network Emulator: QOMET
Authors: Razvan Beuran, Junya Nakata, Takashi Okada, Lan Tien Nguyen, Yasuo Tan, Yoichi Shinoda
Venue: Proceedings of the 22nd International Conference on Advanced Information Networking and Applications - Workshops (2008)

In this paper we present the design and usage of the multi-purpose wireless network emulator that we develop, QOMET. QOMET implements a two-stage scenario-driven approach to wireless network emulation. We give here the details of the improved model and additional functionality that make it currently possible to use QOMET to convert a realworld scenario to a sequence of network-condition descriptors for a wide range of experiments. QOMET was used on a real network testbed to perform experiments involving emulated 802.11 a/b/g WLAN technology over wired networks for several types of scenarios. We shall illustrate this in the final part of the paper, with emphasis on networked robot emulation.
Simulation of the Regenerative Energy Storage with Supercapacitors in Tatra T3A Type Trams
Authors: L. Latkovskis, V. Brais
Venue: Proceedings of the Tenth International Conference on Computer Modeling and Simulation (2008)

The article deals with PSIM simulation results of the regenerative energy storage process with supercapacitors installed on the renewed Tatra T3A tramcars. Bidirectional supercapacitor’s current controller is connected to the filter capacitor of the tram DC converter and in the tram braking mode operates as a buck converter. The control scheme of the buck converter is suggested with two PID control loops: with filter capacitor voltage and supercapacitor current feedback. The results of PSIM simulation of tramcar braking process are given with and without overhead current fluctuations. Simulation results show the control system’s stability in both synchronous and asynchronous operation modes of the tram DC converter and supercapacitor’s current controller.
A new upper bound for the harmonious chromatic number
Authors: Keith Edwards
Venue: Journal of Graph Theory (1998)

A harmonious coloring of a simple graph G is a proper vertex coloring such that each pair of colors appears together on at most one edge. The harmonious chromatic number h(G) is the least number of colors in such a coloring. We obtain a new upper bound for the harmonious chromatic number of general graphs. &copy; 1998 John Wiley & Sons, Inc. J Graph Theory 29: 257&ndash;261, 1998
A Novel ATPG Framework to Detect Weight Related Defects in Threshold Logic Gates
Authors: Manoj Kumar Goparaju, Spyros Tragoudas
Venue: Proceedings of the 26th IEEE VLSI Test Symposium (2008)

The gate that is implemented with threshold logic is called a Threshold Logic Gate (TLG). The logic output value of an TLG depends on the weighted sum of its inputs. Manufactured weights in the threshold logic gates (TLGs) may differ from the designed values and significantly affects the fault coverage. A novel Automatic Test Pattern Generation (ATPG) tool is proposed to detect whether the circuit is malfunctioning due to such weight-related defects.
Architectural modifications to enhance the floating-point performance of FPGAs
Authors: Michael J. Beauchamp, Scott Hauck, Keith D. Underwood, K. Scott Hemmert
Venue: IEEE Transactions on Very Large Scale Integration (VLSI) Systems (2008)

With the density of field-programmable gate arrays (FPGAs) steadily increasing, FPGAs have reached the point where they are capable of implementing complex floating-point applications. However, their general-purpose nature has limited the use of FPGAs in scientific applications that require floating-point arithmetic due to the large amount of FPGA resources that floating-point operations still require. This paper considers three architectural modifications that make floating-point operations more efficient on FPGAs. The first modification embeds floating-point multiply-add units in an island-style FPGA. While offering a dramatic reduction in area and improvement in clock rate, these embedded units are a significant change and may not be justified by the market. The next two modifications target a major component of IEEE compliant floating-point computations: variable length shifters. The first alternative to lookup tables (LUTs) for implementing the variable length shifters is a coarse-grained approach: embedded variable length shifters in the FPGA fabric. These shifters offer a significant reduction in area with a modest increase in clock rate and are smaller and more general than embedded floating-point units. The next alternative is a fine-grained approach: adding a 4:1 multiplexer unit inside a configurable logic block (CLB), in parallel to each 4-LUT. While this offers the smallest overall area improvement, it does offer a significant improvement in clock rate with only a trivial increase in the size of the CLB.
AGAPIA v0.1: A Programming Language for Interactive Systems and Its Typing System
Authors: Cezara Dragoi, Gheorghe Stefanescu
Venue: Electronic Notes in Theoretical Computer Science (ENTCS) (2008)

A model (consisting of rv-systems), a core programming language (for developing rv-programs), several specification and analysis techniques appropriate for modeling, programming and reasoning about interactive computing systems have been recently introduced by Stefanescu using register machines and space-time duality, see [Stefanescu, G. Interactive systems with registers and voices. Fundamenta Informaticae 73 (2006), 285-306. (Early draft, School of Computing, National University of Singapore, July 2004.)]. After that, Dragoi and Stefanescu have developed structured programming techniques for rv-systems and their verification, see, e.g., [Dragoi, C., and G. Stefanescu. Structured programming for interactive rv-systems. Institute of Mathematics of the Romanian Academy, IMAR Preprint 9/2006, Bucharest 2006. Dragoi, C., and G. Stefanescu. Towards a Hoare-like logic for structured rv-programs. Institute of Mathematics of the Romanian Academy, IMAR Preprint 10/2006, Bucharest, 2006. Dragoi, C., and G. Stefanescu. Implementation and verification of ring termination detection protocols using structured rv-programs. Annals of University of Bucharest, Mathematics-Informatics Series, 55 (2006), 129-138. Dragoi, C., and G. Stefanescu. Structured interactive programs with registers and voices and their verification. Draft, Bucharest, January 2007. Dragoi, C., and G. Stefanescu. On compiling structured interactive programs with registers and voices. In: ''Proc. SOFSEM 2008,'' 259-270. LNCS 4910, Springer, 2008.]. In the present paper a kernel programming language AGAPIA v0.1 for interactive systems is introduced. The language contains definitions for complex spatial and temporal data, arithmetic and boolean expressions, modules, and while-programming statements with their temporal, spatial, and spatio-temporal versions. In AGAPIA v0.1 one can write programs for open processes located at various sites and having their temporal windows of adequate reaction to the environment. The main technical part of the paper describes a typing system for AGAPIA v0.1 programs.
Adoption of information systems innovations by individuals: A study of processes involving contextual, adopter, and influencer actions
Authors: Anand Jeyaraj, Rajiv Sabherwal
Venue: Information and Organization (2008)

The extensive literature on the adoption of information systems (IS) or information technology (IT) innovations by individuals has primarily used a variance approach, focusing on individual, organizational, and technological factors that influence the level of adoption. Probably due to this focus on factors affecting adoption, little is known about the processes by which individuals adopt IS/IT innovations. Considering IS/IT adoption as an emergent process involving actions by the potential adopter, actions by individuals who might influence the adopter, and actions within the adopter's context, we examined the ways in which these actions interacted with each other over time. We conducted optimal matching and cluster analyses using data from 27 interviews about the adoption of 30 IS/IT innovations. The emergent taxonomy includes three distinct processes by which individuals adopt innovations: Conscious Quest, Requisite Compliance, and Asserted Trial. The Conscious Quest process, which results in ''full adoption,'' seems to be driven by the adopter, with no social influence and no mandate. In contrast, in Requisite Compliance and Asserted Trial processes, both of which resulted in ''partial adoption,'' the adopter encounters considerable pressure, either from a contextual mandate (Requisite Compliance) or from influencers (Asserted Trial). Implications for research and practice are examined.
Supporting multi-step annotation to promote reflective learning: triggered by a cell-phone
Authors: Kenji Matsuura, Naka Gotoda, Keiji Niki, Kazuhide Kanenishi, Yoneo Yano
Venue: International Journal of Mobile Learning and Organisation (2008)

Many universities officially permit their students to use cell-phone as an input device in lectures. Considering this situation, this paper proposes a multi-step annotation function using a cell-phone as the trigger to start reflective learning. Using the proposed system during the lecture, students are required to mark the important slides via the cell-phone e-mail. This e-mail is synchronised to the respective slide automatically through the time stamp. Then, the student has to fulfil the annotation content marked by the e-mail after the lecture. This paper describes the design and development of the system, including the observed results of trial uses.
The distributed k-server problem-a competitive distributed translator for k-server algorithms
Authors: Y. Bartal, A. Rosen
Venue: Proceedings of the 33rd Annual Symposium on Foundations of Computer Science (1992)

The authors consider the k-server problem in a distributed setting. Given a network of n processors, and k identical mobile servers, requests for service appear at the processors and a server must reach the request point. Besides modeling problems in computer networks where k identical mobile resources are shared by the processors of the network, this models a realistic situation where the transfer of information is costly and there is no central control that governs the behavior of servers that move around to satisfy requests for service. The problem is that of devising algorithms that minimize not only the travel of the server but also the communication cost incurred for the transmission of control messages. The main contribution is a general translator to transform any deterministic global-control competitive k-server algorithm into a distributed competitive one. As consequences they get poly(k)-competitive distributed algorithms for the line, trees and the ring.
DSC-backstepping based robust adaptive NN control for strict-feedback nonlinear systems via small gain theorem
Authors: T. S. Li, B. G. Hong, G. Y. Shi
Venue: International Journal of Systems, Control and Communications (2008)

The adaptive tracking control problem is discussed for a class of strict-feedback uncertain systems. RBF Neural Networks are used to approximate the uncertainties. A unified and systematic procedure is developed to derive a robust adaptive tracking controller with the fusion of dynamic surface control technique and small gain approach. The proposed algorithm can avoid both problems of 'explosion of complexity' and 'curse of dimension' synchronously, thus is convenient to implement in applications. The stability of the closed-loop system is proved. Finally, simulation results via two application examples validate the effectiveness and performance of the proposed scheme.
An efficient technique for incremental updating of association rules
Authors: Tarek F. Gharib, Mohamed Taha, Hamed Nassar
Venue: International Journal of Hybrid Intelligent Systems (2008)

Recent developments in information technology resulted in rapid accumulation of huge amounts of data. Therefore, the task of managing large databases efficiently, in addition to quickly retrieving useful information and mining association rules, has become increasingly important. In this paper, an efficient technique is proposed for updating the discovered association rules in incremental databases. The experimental results show that the proposed algorithm is quite efficient and outperforms other well known algorithms.
Analysis of RSA over Gaussian Integers Algorithm
Authors: Aleksey Koval, Boris S. Verkhovsky
Venue: Proceedings of the Fifth International Conference on Information Technology: New Generations (2008)

In this paper we analyze the extended RSA algorithm into the field of Gaussian integers. We examine in depth the perceived advantages of this extension, such as security and efficiency. We found that the extended RSA is slightly less efficient and could be more secure only if RSA is not as strong as factoring (even in this case it is not guaranteed to add security).
A Distributed Energy-Efficient Flow Protocol for Mobile Ad Hoc Wireless Networks
Authors: Haiyang Hu, Hua Hu
Venue: Proceedings of the 2008 Sixth Annual IEEE International Conference on Pervasive Computing and Communications (2008)

Because of the limited node battery power, energyoptimization is important for the mobile nodes in wirelessad hoc networks. Controlled node mobility is an effectiveapproach to reduce the communication energy consumptionwhile the movement itself consumes energy. Based oncooperative communication (CC) model, the paper takes theenergy consumption of node movement and their residualenergy into account, and then proposes localized algorithmsto direct nodes adapt their transmission power dynamicallyin mobile ad hoc networks. Compared with other algorithmsby simulation, our mechanism shows its efficiency inimproving the system lifetime.
A Parallel Computation of the Steiner Tree Algorithm on Server-Client Paradigm
Authors: Rashid Bin Muhammad
Venue: Proceedings of the 22nd International Conference on Advanced Information Networking and Applications - Workshops (2008)

This paper presents the computational analysis of the Steiner tree problem on the Server-Client model of computation. In particular, this work analyzes the time delays among server and clients for the parallel Steiner tree algorithmand examines some consequences of time delays on the execution time by considering constant and variable delays. The paper also calculates the expression for the optimal number of client processors required by the parallel algorithm for optimal efficiency. The compact mathematical expressions can be used confidently to implement parallel Steiner tree on the Server-Client model of computation.
Subgradients of marginal functions in parametric mathematical programming
Authors: B. S. Mordukhovich, N. M. Nam, N. D. Yen
Venue: Mathematical Programming: Series A and B (2008)

In this paper we derive new results for computing and estimating the so-called Fr&#x00e9;chet and limiting (basic and singular) subgradients of marginal functions in real Banach spaces and specify these results for important classes of problems in parametric optimization with smooth and nonsmooth data. Then we employ them to establish new calculus rules of generalized differentiation as well as efficient conditions for Lipschitzian stability and optimality in nonlinear and nondifferentiable programming and for mathematical programs with equilibrium constraints. We compare the results derived via our dual-space approach with some known estimates and optimality conditions obtained mostly via primal-space developments.
The impact of improved landuse cover on the range of modelled sediment yield from two sub-catchments of the Mae Chaem, Thailand
Authors: M. G. Hartcher, D. A. Post
Venue: Mathematics and Computers in Simulation (2008)

A sediment source, transport, and deposition model known as SedNet has been applied to two sub-catchments of the Mae Chaem River in Thailand, the Mae Suk (95km^2) and the Mae Kong Kha (91km^2). The applied models were analysed to determine the dominant sources and sinks of suspended sediment in these catchments, and to examine the impact of an improved landuse coverage on the range of modelled sediment loads. SedNet model scenarios were run using landuse grids from 1995 to 2003. The 1995 landuse classification was derived from satellite imagery and contained a relatively undifferentiated landuse classification (lumping all forest types into one category); the other in 2003 was derived from a mix of satellite imagery, ground truthing, and mapping, and better differentiated between landuse types (dividing forest types into evergreen, deciduous, and pine plantations). Results indicate significant differences in predicted sediment export in 2003 compared to 1995. It is difficult to say whether these changes were due to actual changes in landuse between 1995 and 2003, or due to the improved landuse classification in 2003. The source areas of suspended sediment also changed significantly between 1995 and 2003, and these changes in source area can clearly be linked to the improved mapping of landuse in 2003. The improved landuse classification in 2003 also led to significant reductions in the range of possible suspended sediment exports from both catchments. Despite these improvements in landuse classification, significant uncertainty in predicted suspended sediment yield still exists for both sub-catchments. Further improvements in identifying the total volume and source areas of suspended sediment will best be achieved through an improved landuse coverage which identifies the type of crop being grown.
An efficient iterative algorithm for image thresholding
Authors: Liju Dong, Ge Yu, Philip Ogunbona, Wanqing Li
Venue: Pattern Recognition Letters (2008)

Thresholding is a commonly used technique for image segmentation. This paper presents an efficient iterative algorithm for finding optimal thresholds that minimize a weighted sum-of-squared-error objective function. We have proven that the proposed algorithm is mathematically equivalent to the well-known Otsu's method, but requires much less computation. The computational complexity of the proposed algorithm is linear with respect to the number of thresholds to be calculated as against the exponential complexity of the Otsu's algorithm. Experimental results have verified the theoretical analysis and the efficiency of the proposed algorithm.
Accessibility and Product Ecosystems
Authors: Jim Tobias
Venue: The Information Society (2007)

Products, including assistive and accessible technologies, do not exist in isolation. They are all part of rich product ecosystems; they inhabit specific niches of economics, functionality, and technology, and they interact with other products. The concept of product ecosystem goes beyond technological interoperability. For accessibility to advance, we must understand more about the interactions among products. This article sketches an explanatory approach that may be useful in understanding how accessible technologies thrive, survive, or fail within their ecosystems.
Perception-motivated interpolation of image sequences
Authors: Timo Stich, Christian Linz, Christian Wallraven, Douglas Cunningham, Marcus Magnor
Venue: Proceedings of the 5th symposium on Applied perception in graphics and visualization (2008)

We present a method for image interpolation which is able to create high-quality, perceptually convincing transitions between recorded images. By implementing concepts derived from human vision, the problem of a physically correct image interpolation is relaxed to an image interpolation that is perceived as physically correct by human observers. We find that it suffices to focus on exact edge correspondences, homogeneous regions and coherent motion to compute such solutions. In our user study we confirm the visual quality of the proposed image interpolation approach. We show how each aspect of our approach increases the perceived quality of the interpolation results, compare the results obtained by other methods and investigate the achieved quality for different types of scenes.
Theory and inference for regression models with missing responses and covariates
Authors: Qingxia Chen, Joseph G. Ibrahim, Ming-Hui Chen, Pralay Senchaudhuri
Venue: Journal of Multivariate Analysis (2008)

In this paper, we carry out an in-depth theoretical investigation for inference with missing response and covariate data for general regression models. We assume that the missing data are missing at random (MAR) or missing completely at random (MCAR) throughout. Previous theoretical investigations in the literature have focused only on missing covariates or missing responses, but not both. Here, we consider theoretical properties of the estimates under three different estimation settings: complete case (CC) analysis, a complete response (CR) analysis that involves an analysis of those subjects with only completely observed responses, and the all case (AC) analysis, which is an analysis based on all of the cases. Under each scenario, we derive general expressions for the likelihood and devise estimation schemes based on the EM algorithm. We carry out a theoretical investigation of the three estimation methods in the normal linear model and analytically characterize the loss of information for each method, as well as derive and compare the asymptotic variances for each method assuming the missing data are MAR or MCAR. In addition, a theoretical investigation of bias for the CC method is also carried out. A simulation study and real dataset are given to illustrate the methodology.