An improved Quiet Direct Simulation method for Eulerian fluids using a second-order scheme In this paper, a second-order scheme for the Quiet Direct Simulation (QDS) of Eulerian fluids is proposed. The QDS method replaces the random sampling method used in Direct Simulation Monte Carlo (DSMC) methods with a technique whereby particles are moved, have their properties distributed onto a mesh, are destroyed and then are recreated deterministically from the properties stored on the mesh using GaussHermite quadrature weights and abscissas. Particles are permitted to move in physically realistic directions so flux exchange is not limited to cells sharing an adjacent interface as in conventional, direction decoupled finite volume solvers. In this paper the method is extended by calculating the fluxes of mass, momentum and energy between cells assuming a linear variation of density, temperature and velocity in each cell and using these fluxes to update the mass, velocity and internal energy carried by each particle. This Euler solver has several advantages including large dynamic range, no statistical scatter in the results, true direction fluxes to all nearby neighbors and is computationally inexpensive. The second-order method is found to reduce the numerical diffusion of QDS as demonstrated in several verification studies. These include unsteady shock tube flow, a two-dimensional blast wave and of the development of Mach 3 flow over a forward facing step in a wind tunnel, which are compared with previous results from the literature wherever is possible. Finally the implementation of QUIETWAVE, a rapid method of simulating blast events in urban environments, is introduced and the results of a test case are presented.

O O B I I O O O O O O O O O O O O O O O O B I I B O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

quiet direct simulation
qds
euler solver


the abc adaptive fusion architecture Contemporary distributed collaborative systems tend to utilize either a client-server or a pure peer-to-peer paradigm. A client-server solution may potentially spawn direct connections between the clients to offload the server thereby creating a hybrid architecture. A pure peer-to-peer paradigm may on the other hand fully eliminate the need for a server. However, some situations call for the strengths of both approaches without relying on either of them. A system might both be used in environments where an infrastructure is present and in environments where it is not. In this paper we present an architecture and early implementation of a system capable of adapting to its operating environment, choosing the best fit combination of the client-server and peer-to-peer architectures. The architecture creates a seamless integration between a centralized hybrid architecture and a decentralized architecture, relying on what we have termed Peer-to-peer Distributed Shared Objects (PDSO). The proposed solution has been implemented and early evaluation has begun. Furthermore, the approach has been utilized to create a real distributed collaborative system for collaboration in hospitals.

O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O B I O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O

hybrid architecture
decentralized architecture
pdso
abc

activity-based computing
ephemeral
accountable
centralized architecture
peer-to-peer distributed shared objects


control of cognitive processes during software design: what tools are needed? A verbal protocol study of professional software designers has revealed three design process control strategies. At least one of them, the generation of opportunistic solutions at different levels of detail accompanied by problem domain modeling, had not been observed in previous empirical studies nor had been acknowledged in the software engineering practices. Specific breakdowns (difficulties) were associated with the different design process control strategies. Software tools should be provided to designers to alleviate these breakdowns. Parts of a cognitive model of software design, based on distributed control from specialists such as design schemas, design heuristics, and design methods, are presented to account for the observed control strategies.

B O B I O B B O B O O O O O O O O B O O O O B O B B O O O O O O B O O O O O O O O O O O O O O O O O O O B I O O O O O O B O O O O O O O O O O B O B B B B O O O O O O O O O O O O B I O B B O O B B O O O O B O B B O B O O O O B O O O B B

empirical studies
software
generation
strategies
cognitive processes
design
cognitive model
account
heuristics
distributed
control
tools

association
software design
level of detail
software tools
schema
practical
design method
domain model
software engineering
design process


Computed NMR shielding increments over benzo-analogs of unsaturated five-membered ring heterocyclic compounds as a measure of aromaticity The GIAO-HF method in Gaussian 03 was used to calculate the isotropic shielding value of the proximal hydrogen of a diatomic hydrogen probe moved in a square grid 2.5 above the plane of 15 benzo-fused analogs of conjugated five-membered ring heterocyclic compounds: pyrrole, furan, thiophene, and phosphole and their 2- and 3-nitrogen analogs. Subtraction of the calculated isotropic shielding value of diatomic hydrogen from each of these isotropic shielding values gave the shielding increment (??) for each probe position. Plotting this value against Cartesian coordinates of the probe position allowed determination of the computed through-space shielding increment surfaces for these compounds. Substantial shielding was observed above the center of each ring, as expected for aromatic compounds. The magnitude of the shielding increment 2.5 above the heterocyclic ring center correlated reasonably well with the only other published method of assessing aromaticity of these systems ASE (aromatic stabilization energy) and with our calculated NICS (nucleus-independent chemical shift) values, another magnetic criterion. The magnitude of the shielding increment measured over the benzene ring midpoint did not correlate well with other measures of aromaticity, however.

O B I O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O

benzo-analogs of conjugated five-membered heterocyclic rings


Crack identification in magnetoelectroelastic materials using neural networks, self-organizing algorithms and boundary element method A hybrid approach using AI tools is proposed for crack identification in magnetoelectroelastic materials. A DBEM formulation is used to obtain the training set of a NN. The training set is separated into small training sets using only intrinsic properties of the data set, using the self-organizing algorithms. Extended displacements taken at a specific boundaries are sufficient to provide good damage identification. Noise sensitivity in the data set was reduced to a minimum using Gaussian mixtures algorithm as automated partitioning method.

O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O

inverse problems
smart materials
self-organizing algorithms


Improved poloidal convergence of the MARS code for MHD stability analysis Most codes for the analysis of magnetohydrodynamics (MHD) stability experience difficulties when the equilibrium is highly shaped or has an X-point. In particular, codes using Fourier expansion in the poloidal direction may need a large number of Fourier components to give reasonably accurate values of the growth rate. In the present work, it is shown that the poloidal convergence can be improved by a judicious choice of normalization factors for the perturbation quantities and multipliers for the equations. Using this method, a new version of the MARS code has been produced with significantly improved poloidal convergence. (C) 1999 Elsevier Science B.V.

O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O


Analysing social behaviour and message dissemination in human based delay tolerant network Recent advances in mobile communication shows proliferation in networks formed by human carried devices known as the pocket switched network (PSN). Human beings are social animals. They tend to form groups and communities, and have repetitive mobility pattern which can be used to disseminate information in PSNs. In this paper, we give a deeper insight to the nature of community formation and how such information can be used to help opportunistic forwarding in mobile opportunistic networks. Using real world mobility traces, we first derive the adjacency list for each node and form the contact graph. Using tools from social network analysis we then determine various node properties like centrality and clustering coefficient and graph properties like average path length and modularity. Based on the derived graph properties, node encounter process and nature of message dissemination in PSNs, we propose two social based routing, known as the contact based routing and community aware two-hop routing. We compare the proposed routing techniques with generic epidemic and prophet routing and Bubble-Rap, a social based routing. Results show that the proposed algorithms is able to achieve better delivery ratio and lower delay than Bubble Rap, while reducing the high overhead ratio of epidemic and prophet routing.

O O O O O O O O O B I I O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

delay tolerant network
pocket switched network
social network analysis


Resource Scheduling Under Uncertainty in a Smart Grid with Renewables and Plug-in Vehicles The power system and transportation sector are our planet's main sources of greenhouse gas emissions. Renewable energy sources (RESs), mainly wind and solar, can reduce emissions from the electric energy sector; however, they are very intermittent. Likewise, next generation plug-in vehicles, which include plug-in hybrid electric vehicles and electric vehicles with vehicle-to-grid capability, referred to as gridable vehicles (GVs) by the authors, can reduce emissions from the transportation sector. GVs can be used as loads, energy sources (small portable power plants) and energy storage units in a smart grid integrated with renewable energy sources. However, uncertainty surrounds the controllability of GVs. Forecasted load is used in unit commitment (UC); however, the actual load usually differs from the forecasted one. Thus, UC with plug-in vehicles under uncertainty in a smart grid is very complex considering smart charging and discharging to and from various energy sources and loads to reduce both cost and emissions. A set of valid scenarios is considered for the uncertainties of wind and solar energy sources, load and GVs. In this paper, an optimization algorithm is used to minimize the expected cost and emissions of the UC schedule for the set of scenarios. Results are presented indicating that the smart grid has the potential to maximally utilize RESs and GVs to reduce cost and emissions from the power system and transportation sector.

O O O B O O B I O O O O O O O O O O O O O O O O O O O B B I O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O B I O O B I O O B O O O O O O O O O O B I O O O O O O O O O O O O O O O O O B O O B I O O O O O O O O O O O O O O O O O O O B O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O B O O O O O O O O O O O O O O O B I O O O O O O O O O O O B O B O O O O O O O

cost
emissions
renewable energy
smart grid
uncertainty
unit commitment


Time-stamped resampling for robust evolutionary portfolio optimization Traditional meanvariance financial portfolio optimization is based on two sets of parameters, estimates for the asset returns and the variancecovariance matrix. The allocations resulting from both traditional methods and heuristics are very dependent on these values. Given the unreliability of these forecasts, the expected risk and return for the portfolios in the efficient frontier often differ from the expected ones. In this work we present a resampling method based on time-stamping to control the problem. The approach, which is compatible with different evolutionary multiobjective algorithms, is tested with four different alternatives. We also introduce new metrics to assess the reliability of forecast efficient frontiers.

O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

robust portfolio
multiobjective evolutionary algorithms


Synchronization stability in complex interconnected neural networks with nonsymmetric coupling ? Some global stability criteria for arrays of linearly coupled delayed neural networks with nonsymmetric coupling are established on the basis of linear matrix inequality (LMI) method, in which the coupling configuration matrix may be arbitrary matrix with appropriate dimensions. Meanwhile, the relations of coupling matrix to stability and synchronization are discussed in detail, and some analysis methods to the synchronization stability of complex networks are also argued. The difficulty arising from the nonsymmetry of the coupling matrix has been overcome in this work. Numerical simulation is also given to verify the effectiveness of the theoretical results.

B I O O O B I O B I O O O O O O O O O O O B I O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

synchronization stability
neural networks
nonsymmetric coupling
complex networks


majic and desktopmajic conferencing system (video program) (abstract only) This video shows a multiparty videoconferencing system MAJIC and a multiparty desktop conferencing system DesktopMAJIC. MAJIC is composed of 2 video cameras, 2 video projectors, a one-way transparent screen, and a tilted workstation forming a desk. Life-size video images of participants are projected without boundaries onto a large curved screen as if users in remote locations are sitting around a table attending a meeting together. MAJIC supports gaze awareness and multiple eye-contact among the participants. Moreover, a shared work space is provided at the center, enabling users to carry on a discussion in a manner comparable to face-to-face meetings. Although MAJIC is very effective, it needs a high speed network and special facilities. DesktopMAJIC is implemented on a convential computer workstation, and supports pseudo gaze awareness and pseudo hand action. Still-picture portraits of the user in 9 different gaze directions are sent to every DesktopMAJIC in advance, and an appropriate one is dynamically selected during the conference to reflect where the user is paying attention. Moreover, other participants' mouse cursors on the shared application window are linked to their portrait window, allowing each user to intuitively see which cursor belongs to whom. Since DesktopMAJIC does not need a high speed network, it may work smoothly even in a telephone or wireless network environment.

O O O O O B O O O O B O O O B O O O O O O O O O O O O O O B O O B O O O O O O O O O O O O O B O O O O O O O O O O O O O O B O O O O O O O O O O B O O O B B O O O O O O O O O O B O O O O O O B O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O B B O O O B O O O O B O O O B O O O O O O O O O O O O O O O O O O O O O O B O O B O O O B O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O B O O O O O O O O O O B O

network video mouse user attention meeting users gaze space awareness videoconferencing action

wireless networks
applications
projector
computation
camera
direct
imaging
participant
sharing
systems
environments
locatability
abstraction
transparency
size
windows
effect


Power estimation of partitioned register files in a clustered architecture with performance evaluation High power Consumption and slow access of enlarged and multiported register files make it difficult to design high performance superscalar processors. The clustered architecture, where the conventional monolithic register file is partitioned into several smaller register files, is expect to overcome the register file issues. In the clustered architecture, the more a monolithic register file is partitioned, the lower power and faster access register files can be realized. However, the partitioning causes losses of IPC (instructions per clock cycle) due to communication among register files. Therefore, degree of partitioning has a strong impact on the trade-off between power consumption and performance. In addition, the organization of partitioned register files also affects the trade-off. In this paper, we attempt to investigate appropriate degrees of partitioning and organizations of partitioned register files in a clustered architecture to assess the trade-off. From the results of execute-driven simulation, we find that the organization of register files and the degree of partitioning have a strong impact on the IPC, and the configuration with non-consistent register files can make use of the partitioned resources more effectively. From the results of register file access time and energy modeling, we find that the configurations with the highly partitioned non-consistent register file organization can receive benefit of the partitioning in terms of operating frequency and access energy of register files. Further, we examine relationship between IPS (instructions per second) and the product of IPC and operating frequency of register files. The results suggest that highly partitioned non-consistent configurations tends to gain more advantage in performance and power.

O O O B I I O O B I O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O B I I O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

clustered architecture
partitioned register files

non-consistent register files
instruction level parallelism


high throughput architecture for h.264/avc motion compensation sample interpolator for hdtv This work presents a new sample interpolator architecture for the motion compensation in H.264/AVC. The proposed solution saves hardware resources through a simplified filters organization, still reaching the needed throughput to real time decoding of HDTV 1920x1080 bi-predictive H.264/AVC video sequences. The new luma interpolator organization uses 4 vertical and 8 horizontal FIR filters and 4 bilinear filters. The chroma interpolator was designed using simplified multipliers. The target technology is Standard-cell implementation using TSMC 0.18 m.

O O O O O B I O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

video coding
hardware architectures
h.264/avc


Multi-objective energy optimization in grid systems from a brain storming strategy Nowadays, companies are more aware of an environmentally responsible use of computational resources. Terms like Green Computing promote energy savings in large-scale and distributed resource centers. Scheduling in distributed systems, as Grid Computing, is a challenging task in terms of time. Current research is considering energy savings as a new promising objective also for meta-schedulers. In this work, energy consumption and execution time are optimized simultaneously using a Multi-objective brain storm algorithm (MOBSA). This new algorithm is compared with two multi-objective algorithms: a novel algorithm based on the fireflies behaviorMulti-objective firefly algorithm (MO-FA)and the well-known Non-dominated Sorting Genetic Algorithm (NSGA-II). Furthermore, other comparisons with real grid meta-schedulers such as Workload Management System from gLite, and Deadline Budget Constraint from Nimrod-G are carried out. The results show that MOBSA provides the best performance in any of the scenarios studied here.

O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O B I O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

scheduling
grid computing
brain storming
energy consumption
execution time


Relations as an abstraction for BDD-based program analysis In this article we present Jedd, a language extension to Java that supports a convenient way of programming with Binary Decision Diagrams ( BDDs). The Jedd language abstracts BDDs as database-style relations and operations on relations, and provides static type rules to ensure that relational operations are used correctly. The article provides a description of the Jedd language and reports on the design and implementation of the Jedd translator and associated runtime system. Of particular interest is the approach to assigning attributes from the high-level relations to physical domains in the underlying BDDs, which is done by expressing the constraints as a SAT problem and using a modern SAT solver to compute the solution. Further, a runtime system is defined that handles memory management issues and supports a browsable profiling tool for tuning the key BDD operations. The motivation for designing Jeddwas to support the development of interrelated whole program analyses based on BDDs. We have successfully used Jedd to build Paddle, a framework of context-sensitive program analyses, including points-to analysis and call graph construction, as well as several client analyses.

B O O O O O B I O O O O O O O O O O B O O O O O O O O B I I O O O O O O O O O B O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

design
binary decision diagrams
relations
java
program analysis

languages
experimentation
language design
boolean formula satisfiability
physical domain assignment
points-to analysis


Benchmarking bibliometrics in biomedical research: research performance of the University of Torontos Faculty of Medicine, 20082012 Bibliometrics are often used as key indicators when evaluating academic groups and individual researchers in biomedical research. Citation metrics, when used as indicators of research performance, require accurate benchmarking for homogenous groups. This study describes the research performance of academic departments in the University of Torontos Faculty of Medicine using article-level bibliometrics for scientific papers published from 2008 to 2012. Eligible publications of all academic faculty members were verified from each researchers curriculum vitae and Web of Science (Thomson Reuters). For 3792 researchers, we identified 26,845 unique papers with 79,502 authors published from 2008 to 2012. The overall mean citations per paper for the faculty was 17.35. The academic departments with the highest levels of collaboration and interdisciplinary research activity also had the highest research impact. The citationwindow for biomedical scientific papers was still active at 5years afterpublication, indicating that the citation window for publications in biomedical research is active longer than previously thought, and this may hinder the reliable use of bibliometrics when evaluating recent scientific publications in biomedical research.

B O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O B I O O O B I O O O O O O O O O O O O O O O O O O O O O B I

benchmarking
research impact
biomedical research
citation window


Learning Prototype Hyperplanes for Face Verification in the Wild In this paper, we propose a new scheme called Prototype Hyperplane Learning (PHL) for face verification in the wild using only weakly labeled training samples (i.e., we only know whether each pair of samples are from the same class or different classes without knowing the class label of each sample) by leveraging a large number of unlabeled samples in a generic data set. Our scheme represents each sample in the weakly labeled data set as a mid-level feature with each entry as the corresponding decision value from the classification hyperplane (referred to as the prototype hyperplane) of one Support Vector Machine (SVM) model, in which a sparse set of support vectors is selected from the unlabeled generic data set based on the learnt combination coefficients. To learn the optimal prototype hyperplanes for the extraction of mid-level features, we propose a Fisher's Linear Discriminant-like (FLD-like) objective function by maximizing the discriminability on the weakly labeled data set with a constraint enforcing sparsity on the combination coefficients of each SVM model, which is solved by using an alternating optimization method. Then, we use the recent work called Side-Information based Linear Discriminant (SILD) analysis for dimensionality reduction and a cosine similarity measure for final face verification. Comprehensive experiments on two data sets, Labeled Faces in the Wild (LFW) and YouTube Faces, demonstrate the effectiveness of our scheme.

O O O O B I I I I O O O O O O O O O B I I O O B I I I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

face verification in the wild
prototype hyperplane learning


An O(1) time algorithm for the 3D euclidean distance transform on the CRCW PRAM model In this paper, we develop a parallel algorithm for the 2D Euclidean distance transform (2D-EDT, for short) of a binary image of size N x N in O(1) time using N(2+delta+epsilon) CRCW processors and a parallel algorithm for the 3D Euclidean distance transform (3D_EDT, for short) of a binary image of size N x N x N in O(1) time using N(3+delta+epsilon) CRCW processors, where delta = 1/k epsilon = 1/2(c+1)-1, k, and c are constants and positive integers. Our 2D_EDT (3D-EDT) parallel algorithm can be used to build up Voronoi diagram and Voronoi polygons (polyhedra) in a 2D (3D) binary image also. All of these parallel algorithms can be performed in O(1) time using N(2+delta+epsilon) (N(3+delta+epsilon)) CRCW processors. To the best of our knowledge, all results derived above are the best O(1) time algorithms known.

O O O O O O O B I I O O B I I O O O O O O B I O O O B I I O O O O O O O O O O O O O O O O O O O O O B I O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

euclidean distance transform
parallel algorithm
voronoi diagram
crcw pram model


Verifying contact hypotheses of planar, polyhedral objects using penetration growth distance The contact between two planar, polyhedral objects can be represented with a set of elementary contacts facevertex contacts. However, not all possible contact representations are geometrically possible. Verification of whether a set of elementary contacts is geometrically feasible is in particular difficult if the elementary contacts do not fully constrain the relative configuration of the objects. These are exactly the contact descriptions that allow the objects to move compliantly with respect to each other and are therefore important for motion planning. An equivalent optimization problem is posed to verify geometric feasibility of contact descriptions that do not fully constrain the relative configuration. A trajectory following algorithm has been implemented and applied to test feasible and infeasible contact representations. The results of this work can be used to implement a predicate that verifies whether a contact representation is geometrically possible.

O B O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O B O O O O


In computation, parallel is nothing, physical everything - Discussion Andrew Boucher (1997) argues that "parallel computation is fundamentally different from sequential computation'' (p. 543), and that this fact provides reason to be skeptical about whether AI can produce a genuinely intelligent machine. But parallelism, as I prove herein, is irrelevant. What Boucher has inadvertently glimpsed is one small part of a mathematical tapestry portraying the simple but undeniable fact that physical computation can be fundamentally different from ordinary, "textbook'' computation (whether parallel or sequential). This tapestry does indeed immediately imply that human cognition may be uncomputable.

O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

artificial intelligence
simulation proofs
turing machines
uncomputable functions


An all digital PLL with an active inductor DCO for LTE applications in 0.13 mu m CMOS In this paper, we propose a low-power all digital phase-locked loop with a wide input range, and a high resolution TDC that uses phase-interpolator and a time amplifier. The resolution of the proposed TDC is improved by using a phase-interpolator which divides the inverter delay time and the time amplifier which extends the time difference between the reference frequency and the DCO clock. The phase noise of the proposed ADPLL is improved by using a fine resolution DCO with an active inductor. In order to control the frequency of the DCO, the transconductance of the active inductor is tuned digitally. To cover the wide tuning range and to operate at a low-power, a three-step coarse tuning scheme is used. In addition, the DCO gain needs to be calibrated digitally in order to compensate for gain variations. The die area of the ADPLL is 0.8 mm(2) using 0.13 mu m CMOS technology. The frequency resolution of the TDC is 1 ps. The DCO tuning range is 58% at 2.4 GHz and the effective DCO frequency resolution is 0.14 kHz. The phase noise of the ADPLL output at 2.4 GHz is -120.5 dBc/Hz with a 1 MHz offset. The total power consumption of the ADPLL is 12 mW from a 1.2 V supply voltage.

O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

all-digital phase-locked loop (adpll)
time-to-digital converter (tdc)
phase-interpolator
wide tuning range frequency
fine-resolution
digitally controlled oscillator (dco)


Theorem proving based on the extension rule Methods based on resolution have been widely used for theorem proving since it was proposed. This paper presents a new method for theorem proving that uses the inverse of resolution and employs the inclusion-exclusion principle to circumvent the problem of space complexity. We prove its soundness and completeness. The concept of complementary factor is introduced to estimate its complexity. We also show that our method outperforms resolution-based methods in some cases. Thus it is potentially a complementary method to resolution-based methods.

B I O O O B I O O O O O O O O O B I O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O

theorem proving
extension rule
complementary factor


Multilocus genetic models of handedness closely resemble single-locus models in explaining family data and are compatible with genome-wide association studies Right- and left-handedness run in families, show greater concordance in monozygotic than dizygotic twins, and are well described by single-locus Mendelian models. Here we summarize a large genome-wide association study (GWAS) that finds no significant associations with handedness and is consistent with a meta-analysis of GWASs. The GWAS had 99% power to detect a single locus using the conventional criterion of P < 5 10?8 for the single locus models of McManus and Annett. The strong conclusion is that handedness is not controlled by a single genetic locus. A consideration of the genetic architecture of height, primary ciliary dyskinesia, and intelligence suggests that handedness inheritance can be explained by a multilocus variant of the McManus DC model, classical effects on family and twins being barely distinguishable from the single locus model. Based on the ENGAGE meta-analysis of GWASs, we estimate at least 40 loci are involved in determining handedness.

O O O O B O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O B O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O B B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B


A network of pyramidal neurons is sensitive to the timing of its excitatory inputs The transmission of excitatory inputs by a network of coupled pyramidal cells is investigated by means of numerical simulations. The pyramidal cell models are coupled by excitatory synapses and each one receives an excitatory pulse at a random time extracted from a Gaussian distribution. Moreover, each cell model is injected with a noisy current. It was found that the excitatory coupling promotes the transmission of the synaptic inputs on a time scale of a few ms.

O B O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


Dynamic disparity adjustment and histogram-based filtering of range data for fast 3-D hand tracking ? Range data is very important in human-computer interaction applications. Although less costly, range acquisition and processing still presents a speed vs data reliability tradeoff. This paper proposes a method that, given noisy and generally unreliable range data, can filter out erroneous information using range histograms for regions of interest selected in registered color data. Then, using the resulting consistent data that has passed filters, this method limits the depth search space dynamically using motion history and its current state. Experimental results demonstrate the success of the proposed algorithm. Using filtered range data, the algorithm correctly identified the hand involved in manipulation 99.85% of the time. Dynamic disparity adjustment produced a speedup of 60.17% over a static disparity range selection. An application to virtual reality navigation is also presented.

B I I O O O O B I O O O B I O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O

range data
hand tracking
dynamic disparity adjustment

motion analysis
human-computer interaction
histogram-based filtering
region detection and identification


Team cognition: Development and evolution in software project teams In software development, team-based work structures are commonly used to accomplish complex projects. Software project teams must be able to utilize the expertise and knowledge of participants without overwhelming individual members. To efficiently leverage individuals' knowledge and expertise, software project teams develop team cognition structures that facilitate their knowledge activities. This study focuses on the emergence and evolution of team cognition in software project teams, and examines how communication activity and team diversity impact the formation of these structures. A longitudinal study was conducted of 51 database development teams. The results suggest that some forms of communication and team diversity affect the formation of team cognition. Frequency of meetings and phone calls were positively related to the formation of team cognition, while e-mail use had no effect. Gender diversity had a strong and positive effect on the development of team cognition and the effect remained stable over time. Implications for the practical potential and limitations of purposive team construction as a strategy for improving software development team performance are discussed.

O O O O O O O B I O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

expertise location
member familiarity
shared task understanding
software teams
team communications


Pretopologies and dynamic spaces Approximation Spaces were introduced in order to analyse data on the basis of Indiscernibility Spaces, that is, spaces of the form , where U is a universe of items and E is an equivalence relation on U. Various authors suggested to consider spaces of the form , where R is any binary relation. This paper aims at introducing a further step consisting in taking into account spaces of the form , where {R-i} (iepsilonI), is a family of binary relations, that we call "Dynamic Spaces" because by means of this generalisation we can account for different forms of dynamics. While Indiscernibility Spaces induce 0-dimensional topological spaces (Approximation Spaces), Dynamic Spaces induce various types of pre-topological spaces.

B O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O B O O O O O O O B I O O O O O O O O

pretopologies
relations
approximation spaces
dynamics


A novel solution to the energy hole problem in sensor networks One major limitation in a Wireless Sensor Network (WSN) is the energy dissipation of the nodes and the lifetime of the node's battery. The traffic in a sensor network follows a many-to one pattern, where nodes nearer to the sink carry heavier traffic loads. Therefore, the nodes around the sink would deplete their energy faster, leading to what is known as an energy hole around the sink. The aim of this paper is to overcome the power constraints in WSN by wirelessly charging the nodes. We investigate both theoretically and through simulations whether the physical phenomenon of long-lifetime resonant electromagnetic states with localized slowly-evanescent field patterns can be used to transfer energy efficiently over multiple hops. We specify the hardware the modified sensor node needs in order to wirelessly transmit and receive energy and introduce a new layer called the charging layer into the sensor network protocol stack. Our results show that multi-hop wireless energy transfer can be done with an efficiency as high as 20% over 8 hops. The work in this paper is the first that addresses multi-hop wireless energy transfer in sensor networks and is the building block for our and other future research in this area.

O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O B I O B I O O O O O O O O O O O O O O

sensor networks
energy transfer
charging


Compactons in discrete nonlinear Klein-Gordon models In this short communication we study compactons in the setting of discrete nonlinear Klein-Gordon (DNKG) chains. The temporal and spatial dependences of the solutions are separated resulting in an array of coupled nonlinear algebraic equations for the spatial dependence and an ordinary differential equation for the temporal dependence. The corresponding equations are studied and their potential for supporting exact discrete solutions with compact support is identified. Finally, a particular set of KG nonlinearities of relevance to applications is studied, its discrete compacton solutions are obtained and their stability properties are examined. (C) 2002 IMACS. Published by Elsevier Science B.V. All rights reserved.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O

discrete nonlinear klein-gordon chain
discrete solution


feasibility and pragmatics of classifying working memory load with an electroencephalograph A reliable and unobtrusive measurement of working memory load could be used to evaluate the efficacy of interfaces and to provide real-time user-state information to adaptive systems. In this paper, we describe an experiment we con-ducted to explore some of the issues around using an elec-troencephalograph (EEG) for classifying working memory load. Within this experiment, we present our classification methodology, including a novel feature selection scheme that seems to alleviate the need for complex drift modeling and artifact rejection. We demonstrate classification accuracies of up to 99\% for 2 memory load levels and up to 88\% for 4 levels. We also present results suggesting that we can do this with shorter windows, much less training data, and a smaller number of EEG channels, than reported previously. Finally, we show results suggesting that the models we construct transfer across variants of the task, implying some level of generality. We believe these findings extend prior work and bring us a step closer to the use of such technologies in HCI research.

O O O O O O B I O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O B O O O O B I O O O O O O O O O O O O O O O O B O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

classification
feature selection
memory load

cognitive load
machine learning
brain-computer interface
electroencephalography (eeg)


Topology optimization using a mixed formulation: An alternative way to solve pressure load problems A shortcoming of the traditional density based approach to topology optimization is the handling of design dependent loads that relate to boundary data, such as for example pressure loads. Previous works have introduced spline and iso-density curves or alternative parametrization schemes to determine the load surfaces. In this work we suggest a new way to solve pressure load problems in topology optimization. Using a mixed displacementpressure formulation for the underlying finite element problem, we define the void phase to be an incompressible hydrostatic fluid. In this way we can transfer pressure loads through the fluid without any needs for special load surface parametrizations. The method is easily implemented in the standard density approach and is demonstrated to work efficiently for both 2D and 3D problems. By extending the method to a three phase (solid/fluid/void) design method we also demonstrate design of water containing dams.

B I O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

structural optimization
finite elements
mixed forms
incompressibility


Designing embedded systems using patterns: A case study If software for embedded processors is based on a time-triggered architecture, using co-operative task scheduling, the resulting system can have very predictable behaviour. Such a system characteristic is highly desirable in many applications, including (but not restricted to) those with safety-related or safety-critical functions. In practice, a time-triggered, co-operatively scheduled (TTCS) architecture is less widely employed than might be expected, not least because care must be taken during the design and implementation of such systems if the theoretically predicted behaviour is to be obtained. In this paper, we argue that the use of appropriate design patterns can greatly simplify the process of creating TTCS systems. We briefly explain the origins of design patterns. We then illustrate how an appropriate set of patterns can be used to facilitate the development of a non-trivial embedded system.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O B I

time-triggered
co-operating scheduling
microcontroller


alpha-words and the radix order Let alpha = (a(1), a(2),...) be a sequence (finite or infinite) of integers with a(1) >= 0 and a(n) >= 1, for all n >= 2. Let {a, b} be an alphabet. For n >= 1, and r = r(1)r(2)...r(n) is an element of N(n) with 0 = 2. Many interesting combinatorial properties of alpha-words have been studied by Chuan. In this paper, we obtain some new methods of generating the distinct alpha-words of the same order in lexicographic order. Among other results, we consider another function r bar right arrow w[r] from the set of labels of alpha-words to the set of alpha-words. The string r is called a new label of the alpha-word w[r]. Using any new label of an nth-order alpha-word w, we can compute the number of the nth-order alpha-words that are less than w in the lexicographic order. With the radix orders <(r) on N(n) (regarding N as an alphabet) and {a, b}(+) with a <(r) b, we prove that there exists a subset D of the set of all labels such that w[r] <(r) w[s] whenever r, s is an element of D and r <(r) S. (C) 2010 Elsevier B.V. All rights reserved.

O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


LR Characterization of Chirotopes of Finite Planar Families of Pairwise Disjoint Convex bodies We extend the classical LR characterization of chirotopes of finite planar families of points to chirotopes of finite planar families of pairwise disjoint convex bodies: a map on the set of 3-subsets of a finite set is a chirotope of finite planar families of pairwise disjoint convex bodies if and only if for every 3-, 4-, and 5-subset of the restriction of to the set of 3-subsets of is a chirotope of finite planar families of pairwise disjoint convex bodies. Our main tool is the polarity map, i.e., the map that assigns to a convex body the set of lines missing its interior, from which we derive the key notion of arrangements of double pseudolines, introduced for the first time in this paper.

O O O B O O O O O O O O O O O O O O O O B O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

convexity
discrete geometry
projective planes
pseudoline arrangements


Efficient, ROM-less DDFS using non-linear interpolation and non-linear DAC A non-linear interpolation based ROM-less Direct Digital Frequency Synthesisiser (DDFS) is more efficient than previous systems as each current cell in a non-linear DAC is used more effectively. This was achieved by forming an analogue voltage from a small linear DAC addressed by phase bits that are usually discarded. The analogue voltage was connected to a selected current source in a thermometer decoded non-linear DAC to allow non-linear interpolation between the conventional, phase limited output levels. By increasing the number of phase bits the spurious free dynamic range (SFDR) was improved without increasing the size of the non-linear DAC. Modelling and simulation of the non-linear response of the differential switch based current cell revealed suitable parameters. The architecture of 64 current cells used a modified thermometer decoder and three-state switch in each current cell. Simulation and testing of 10 sample circuits demonstrated a robust DDFS with SFDR better than -60 dBc and suitable for use in a wide range of instrumentation systems.

O O B O O O O B I O O O O O O O O O B O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O B I

ddfs
instrumentation systems
nonlinear dac

direct digital frequency synthesis
waveform generation


Multiobjective optimization for multiproduct batch plant design under economic and environmental considerations This work deals with the multicriteria cost-environment design of multiproduct batch plants, where the design variables are the size of the equipment items as well as the operating conditions. The case study is a multiproduct batch plant for the production of four recombinant proteins. Given the important combinatorial aspect of the problem, the approach used consists in coupling a stochastic algorithm, indeed a genetic algorithm (GA) with a discrete-event simulator (DES). Another incentive to use this kind of optimization method is that, there is no easy way of calculating derivatives of the objective functions, which then discards gradient optimization methods. To take into account the conflicting situations that may be encountered at the earliest stage of batch plant design, i.e. compromise situations between cost and environmental consideration, a multiobjective genetic algorithm (MOGA) was developed with a Pareto optimal ranking method. The results show how the methodology can be used to find a range of trade-off solutions for optimizing batch plant design. (c) 2005 Elsevier Ltd. All rights reserved.

O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O

multicriteria genetic algorithm
environmental impact


Object matching algorithms using robust Hausdorff distance measures A Hausdorff distance (HD) is one of commonly used measures for object matching. This work analyzes the conventional HD measures and proposes two robust HD measures based on Mi-estimation and least trimmed square (LTS) which are more efficient than the conventional HD measures. By computer simulation, the matching performance of the conventional and proposed HD measures is compared with synthetic and real images.

B I O O O B I O O B I O O O O O O O O B I O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

hausdorff distance
least trimmed square
object matching


Analyzing midpoint subdivision Midpoint subdivision generalizes the Lane-Riesenfeld algorithm for uniform tensor product splines and can also be applied to non-regular meshes. For example, midpoint subdivision of degree 2 is a specific Doo-Sabin algorithm and midpoint subdivision of degree 3 is a specific Catmull-Clark algorithm. In 2001, Zorin and Schroder were able to prove C(1)-continuity for midpoint subdivision surfaces analytically up to degree 9. Here, we develop general analysis tools to show that the limiting surfaces under midpoint subdivision of any degree >= 2 are C(1)-continuous at their extraordinary points. (C) 2011 Elsevier B.V. All rights reserved.

O B I B I O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O

spectral properties of subdivision matrices


On the frequency estimation of signal by using the expansion of LP method in the noisy circumstance In this paper, we present a new signal frequency estimation method based on the sinusoidal additive synthesis model. In the proposed method, frequencies in both the signal and noise are estimated with several delay times by using an expanded linear prediction (LP) method, and assuming that the signal is stationary and noise is unstationary in short record length. Frequencies in the signal are extracted according to their dependence on different delays. The frequency estimation can be accomplished with short record length even in the case where the number of frequency components in the signal is unknown. And it is capable of estimating the frequencies of a signal in the presence of noise. Furthermore, the proposed method estimates the parameters with less computation and high estimation accuracy. Simulation results are provided to confirm the effectiveness of the proposed method. The comparison of estimation accuracy between the proposed method and the analysis by synthesis (ABS) method is shown with the corresponding Cramer-Rao lower bound. And the frequency resolution of this method is also shown.

O O B I O O O O O O O O O O O O O O O O O O O O O B I O O O O B I I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

frequency estimation
sinusoidal additive synthesis model


Likelihood ratio test for simultaneous testing of the mean and the variance of a normal distribution In this paper, we consider the simultaneous testing of the mean and; the variance of a normal distribution. The exact distribution of the likelihood ratio test statistic is obtained, which is not available in the literature. The critical points of the exact test are reported. We also consider some of the other exact and asymptotic tests. The powers of these tests are compared using the Monte Carlo simulations.

B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

uniformly most powerful test
uniformly most powerful unbiased test
confidence intervals


Influence of Industry Characteristics on Information Technology Outsourcing Despite the extensive research on information technology (IT) outsourcing, our knowledge and understanding of how industry characteristics impact the use of IT outsourcing remain limited. Drawing upon theories from organization behavior and industrial economics, this study identifies four major industry characteristics (i.e., munificence, dynamism, concentration, and capital intensity) and investigates how each of these factors affects the use of IT outsourcing. Specifically, we postulate that the extent of industry munificence is positively related to the utilization of IT outsourcing. Since timely strategic actions are the crucial aspects of leveraging munificent resources, IT outsourcing, which can be implemented in short periods of time, is considered to be a preferred option in such environments. Furthermore, industry dynamism is also positively associated with IT outsourcing, given that firms in dynamically evolving industries tend to look for flexibility and avoid a large amount of fixed investments (e.g., IT development in-house). In contrast to these hypotheses, we predict that industry concentration is negatively related to IT outsourcing. Firms in concentrated industries are likely to develop their own IT infrastructures, as they are not constrained by institutional pressures or cost-driven strategic actions. Finally, because firms in capital-intensive industries tend to conform to long-standing traditional practices, and do not highly value novel and risky practices, they will be less likely to use IT outsourcing than firms in industries with low capital intensity. The data from the U.S. Bureau of Economic Analysis along with Compustat empirically validated all of the proposed hypotheses; however, only marginal support was found for the association between industry concentration and IT outsourcing. Our findings offer business executives and IT service providers strategic and managerial insights into the dynamics and complexities involved in the diverse aspects of industry environments and IT outsourcing decisions.

O O O O O O O O O O O O O O O B I O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O B I O O O O O O O B I O O O O O O O B I O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O B I O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O B I O O O O O O O O O O O O O O O O O O O O O O O O B I O B I O

capital intensity
industry concentration
industry dynamism
industry environments
industry munificence
it outsourcing


A procedure to enhance identification of recurrent neural networks for simulating airfuel ratio dynamics in SI engines The paper deals with the identification of recurrent neural networks (RNNs) for simulating the airfuel ratio (AFR) dynamics into the intake manifold of a spark ignition (SI) engine. RNN are derived from the well-established static multi layer perceptron feedforward neural networks (MLPFF), that have been largely adopted for steady-state mapping of SI engines. The main contribution of this work is the development of a procedure that allows identifying a RNN-based AFR simulator with high generalization and limited training data set. The procedure has been tested by comparing RNN simulations with AFR transients generated using a nonlinear-dynamic engine model. The results show how training the network making use of inputs that are uncorrelated and distributed over the entire engine operating domain allows improving model generalization and reducing the experimental burden. Potential areas of application of the procedure developed can be either the use of RNN as virtual AFR sensors (e.g. engine or individual AFR prediction) or the implementation of RNN in the framework of model-based control architectures.

O O O O O O O B I O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

engine modeling
engine control
nonlinear dynamic modeling
air-to-fuel ratio control
recurrent neural networks


Integrating Memory Optimization with Mapping Algorithms for Multi-Processors System-on-Chip Due to their great ability to parallelize at a very high integration level, Multi-Processors Systems-on-Chip (MPSoCs) are good candidates for systems and applications such as multimedia. Memory is becoming a key player for significant improvements in these applications (power, performance and area). The large amount of data manipulated by these applications requires high-capacity computing and memory. Lately, new programming models have been introduced. This leads to the need of new optimization and mapping techniques suitable for embedded systems and their programming models. This article presents novel approaches for combining memory optimization with mapping of data-driven applications while considering anti-dependence conflicts. Two different approaches are studied and integrated with existing mapping algorithms. The first approach (based on heuristic algorithms) keeps the graph transformation for memory optimization stage from the mapping stage and enables their combination in a design flow. The second approach (based on evolutionary algorithms) combines these two stages and integrates them in a unique stage. Some significant improvements are obtained for memory gain, communication load and physical links.

O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B B O O O O O O O O O O O O B O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O

design
performance
embedded systems
memory
multimedia

experimentation
data locality
compiler transformations
data cache
optimizations
multiprocessors system on chip


SYSTEMS-ANALYSIS - A DECISION APPROACH This work presents a meta-theory for deciding which systems analysis method should be used in a given circumstance. The decisions are to be based upon three criteria: (a) scope, (b) structure, and (c) nature of the process to be supported by information systems. Four development strategies are based on: (a) end-user development, (b) inquiring systems, (c) decision analysis, and (d) data analysis. The paper summarizes the decision and data analysis methods, and discusses the inquiring systems method in more detail.

O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O B I O O B I O O O O O O B I O O O O B I O O O O

systems analysis
inquiring systems
decision analysis
data analysis

systems development
prototyping
reengineering
end-user development


reducing normative conflicts in information security Security weaknesses often stem from users trying to comply with social expectations rather than following security procedures. Such normative conflicts between security policies and social norms are therefore undesirable from a security perspective. It has been argued that system developers have a "meta-task responsibility", meaning that they have a moral obligation to enable the users of the system they design to cope adequately with their responsibilities. Depending on the situation, this could mean forcing the user to make an "ethical" choice, by "designing out" conflicts. In this paper, we ask the question to what extent it is possible to detect such potential normative conflicts in the design phase of security-sensitive systems, using qualitative research in combination with so-called system models. We then envision how security design might proactively reduce conflict by (a) designing out conflict where possible in the development of policies and systems, and (b) responding to residual and emergent conflict through organisational processes. The approach proposed in this paper is a so-called subcultural approach, where security policies are designed to be culturally sympathetic. Where normative conflicts either cannot be avoided or emerge later, the organisational processes are used to engage with subcultures to encourage communally-mediated control.

O B I O B I O O O O O O O O O O O O O O O O O O B I O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O B I O O O O O O O O O O O O O O O B O O O O

security policies
information security
system models
subcultures
normative conflicts

policy alignment
meta-task responsibility


Improved bounds on sorting by length-weighted reversals We study the problem of sorting binary sequences and permutations by length-weighted reversals. We consider a wide class of cost functions, namely f(l) = l(alpha) for all alpha >= 0, where l is the length of the reversed subsequence. We present tight or nearly tight upper and lower bounds on the worst-case cost of sorting by reversals. Then we develop algorithms to approximate the optimal cost to sort a given input. Furthermore, we give polynomial-time algorithms to determine the optimal reversal sequence for a restricted but interesting class of sequences and cost functions. Our results have direct application in computational biology to the field of comparative genomics. (c) 2007 Elsevier Inc. All rights reserved.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

potential functions
dynamic programming
soiling 0/1 sequences by reversals
modeling genome rearrangements


Full-Information Lookups for Peer-to-Peer Overlays Most peer-to-peer lookup schemes keep a small amount of routing state per node, typically logarithmic in the number of overlay nodes. This design assumes that routing information at each member node must be kept small so that the bookkeeping required to respond to system membership changes is also small, given that aggressive membership dynamics are expected. As a consequence, lookups have high latency as each lookup requires contacting several nodes in sequence. In this paper, we question these assumptions by presenting a peer-to-peer routing algorithm with small lookup paths. Our algorithm, called "OneHop," maintains full information about the system membership at each node, routing in a single hop whenever that information is up to date and in a small number of hops otherwise. We show how to disseminate information about membership changes quickly enough so that nodes maintain accurate complete membership information. We also present analytic bandwidth requirements for our scheme that demonstrate that it could be deployed in systems with hundreds of thousands of nodes and high churn. We validate our analytic model using a simulated environment and a real implementation. Our results confirm that OneHop is able to achieve high efficiency, usually reaching the correct node directly 99 percent of the time.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

distributed systems
peer to peer
network topology
routing protocol
distributed data structures


Real-time analysis of ships in radar images with neural networks This paper shows the effectiveness of using neural paradigms to filter, enhance and restore radar images of ships sailing in low visibility conditions. The task, to be accomplished in real time, is inserted in a processing chain which provides the mobile trajectory. Adaptive vector quantization techniques (supervised and unsupervised) and back-propagation neural algorithms are considered. The final optimized architecture contains a small set of processing modules comprising, at most, two pipelined neural convolvers (an enhancing filter and a classifier). Each neural-convolver mask is characterized by a symmetrical structure whose optimal coefficients have been determined via learning.

O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

feature extraction
optimized learning
pattern classification
recognition
symmetrical convolvers


CXC Receptor and Chemokine Expression in Human Meningioma Recent evidence indicates that cancer cells express chemokine (CK) receptors and that their signaling is crucial for tumor proliferation, migration, and angiogenesis. The profiles of expression of CXC CK receptors (CXCR1-5) and their main ligands (growth-related oncogene, GRO1-2-3/CXCL1-2-3; interleukin 8, IL-8/CXCL8; monokine-induced ?-interferon MIG/CXCL9; ?-interferon-inducible-protein-10, IP-10/CXCL10; stromal cell-derived factor-1, SDF1/CXCL12; B-cell activating CK-1, BCA-1/CXCL13) were analyzed by reverse transcription polymerase chain reaction (RT-PCR) in surgical samples of human meningiomas. All the five receptors displayed high percentages of positive case

O B O B O O O B O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


Surface grading of bamboo strips using multi-scale color texture features in eigenspace In order to achieve high competitive quality of bamboo products, it appears that bamboo strips with naturally different tonalities should be elaborately sorted into different classes according to their global color texture appearance. Inspired by the coarse-to-fine visual perception process of human vision system, this paper proposes a new surface grading approach by integrating the color and texture of bamboo strips based on Gaussian multi-scale space. The multi-scale representations of color texture for the original image of bamboo strips could be obtained and used to construct the multivariate image, each channel of which represents a perceptual observation from different scales. The multivariate image analysis (MIA) techniques are used to extract multi-scale features from the resulting multivariate image data. The characteristic images corresponding to typical classes are selected to build the model of the reference eigenspace. The novel testing images and the training images are all projected onto this reference eigenspace to obtain their representative feature clusters. And the Bhattacharyya distance is used to estimate the similarity of the representative feature clusters between the testing images and the training images in the eigenspace. Then a k-NN classifier is adopted to classify the testing images into the given classes of training images. Comparative experiments have been carried out on a set of actual bamboo strip images and the experimental results verify the effective discrimination of multi-scale color texture eigenspace features and good classification accuracy of the proposed surface grading method.

B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O B I O

surface grading
multivariate image analysis
eigenspace features
bhattacharyya distance

multi-scale representations
k-nn classification


refactoring java programs for flexible locking Recent versions of the Java standard library offer flexible locking constructs that go beyond the language's built-in monitor locks in terms of features, and that can be fine-tuned to suit specific application scenarios. Under certain conditions, the use of these constructs can improve performance significantly, by reducing lock contention. However, the code transformations needed to convert between locking constructs are non-trivial, and great care must be taken to update lock usage throughout the program consistently. We present Relocker , an automated tool that assists programmers with refactoring synchronized blocks into ReentrantLocks and ReadWriteLocks , to make exploring the performance tradeoffs among these constructs easier. In experiments on a collection of real-world Java applications, Relocker was able to refactor over 80\% of built-in monitors into ReentrantLocks . Additionally, in most cases the tool could automatically infer the same ReadWriteLock usage that programmers had previously introduced manually.

B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O


User-friendly software for the analysis of brain lesions (ABLe) We previously developed a software package called ABLe (analysis of brain lesions) which characterizes brain lesions in terms of lesion volume and intersection with cytoarchitecture (e.g. Brodmann areas). Since our previous publication, there have been significant improvements to this software package which utilize methods standard to the neuroimaging community. These features include spatial normalization to the MNI template brain (standard of the international consortium for brain mapping), and use of the volume occupancy Talairach labels (VOTL) and automated anatomical labeling (AAL) atlases for full brain quantification of structures impacted by the lesion. Methods for multi-subject studies including lesion-symptom mapping proposed by Bates et al. have been extended in ABLe to produce an exploratory analysis summarizing correlations between subjects with overlapping lesions and behavioral deficit. A subset of data from an ongoing traumatic head injury study correlating deficit with brain anatomy is used to demonstrate the power of this software package.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

brain lesion
computer software
prefrontal cortex


On the convergence of uncertain sequences Uncertain variables are measurable functions from uncertainty spaces to the set of real numbers. In this paper, a new kind of convergence, convergence uniformly almost surely (convergence uniformly a.s.), is presented. Then, relations between convergence uniformly almost surely and convergence almost surely (convergence a.s.), convergence in measure, convergence in mean, and convergence in distribution are discussed. (C) 2008 Elsevier Ltd. All rights reserved.

O O B O O O O O O O O O O O O O O O O O O O O O O O O B B O O O B O O O O O O O B O O O O B O O B O B O O B O O O B O O O O O O O O O O O

uncertain measure
uncertain variable
expected value


Complex variable boundary integral equations for perforated infinite planes A fast and stable numerical algorithm is presented for the elastostatic problem of a linearly elastic plane with holes, loaded at infinity. The holes are free of stress. The algorithm is based on an integral equation which is intended as an alternative to the classic ShermanLauricella equation. The new scheme is argued to be both simpler and more reliable than schemes based on the ShermanLauricella equation. Improvements include simpler geometrical description, simpler relationships between mathematical and physical quantities, simpler extension to problems involving also inclusions and cracks, and more stable numerical convergence.

O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O B O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O

linear elasticity
integral equation of fredholm type
fast multipole method
effective elastic moduli
stress concentration factor
numerical methods
stable algorithms


Selecting critical clinical features for heart diseases diagnosis with a real-coded genetic algorithm In clinic, normally a lot of diagnostic features are recorded from a patient for a certain disease. It will be beneficial for the prompt and correct diagnosis of the disease by selecting the important and relevant features and discarding those irrelevant and redundant ones. In this paper, a real-coded genetic algorithm (GA)-based system is proposed to select the critical clinical features essential to the heart diseases diagnosis. The heart disease database used in this study includes 352 cases, and 40 diagnostic features were recorded for each case. Using the proposed genetic algorithm, 24 critical features have been identified, and their corresponding diagnosis weights for each heart disease of interest have been determined. The critical diagnostic features and their clinic meanings are in sound agreement with those used by the physicians in making their clinic decisions.

O O O O O B I I O O O B I O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O B I I O O O O O O O O O O O O O B I O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O

heart diseases diagnosis
diagnostic features
genetic algorithm

feature selection
differential diagnosis


A GRASPELS approach for the job-shop with a web service paradigm packaging We present an original GRASPELS approach for job-shop solving. Indirect representation of solution permits to better investigate the search space. The GRASPELS is evaluated with 11 previously published methods. Results prove that the method is state of the art. GRASPELS is packaged into a web service.

O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I


Backdoors to tractable answer set programming ? Answer Set Programming (ASP) is an increasingly popular framework for declarative programming that admits the description of problems by means of rules and constraints that form a disjunctive logic program. In particular, many AI problems such as reasoning in a nonmonotonic setting can be directly formulated in ASP. Although the main problems of ASP are of high computational complexity, complete for the second level of the Polynomial Hierarchy, several restrictions of ASP have been identified in the literature, under which ASP problems become tractable. In this paper we use the concept of backdoors to identify new restrictions that make ASP problems tractable. Small backdoors are sets of atoms that represent clever reasoning shortcuts through the search space and represent a hidden structure in the problem input. The concept of backdoors is widely used in theoretical investigations in the areas of propositional satisfiability and constraint satisfaction. We show that it can be fruitfully adapted to ASP. We demonstrate how backdoors can serve as a unifying framework that accommodates several tractable restrictions of ASP known from the literature. Furthermore, we show how backdoors allow us to deploy recent algorithmic results from parameterized complexity theory to the domain of answer set programming.

B O O B I I O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O B I O O O O O B I I

answer set programming
backdoors
computational complexity
parameterized complexity


Variable neighborhood search for the dial-a-ride problem In dial-a-ride problems passengers have to be transported between pre-specified pickup and delivery locations under user inconvenience considerations. The problem variant considered in this paper aims at minimizing total routing costs while respecting maximum route duration limits, time windows, and maximum user ride time limits. We propose a competitive variable neighborhood search-based heuristic, using three classes of neighborhoods. The first neighborhood class uses simple swap operations tailored to the dial-a-ride problem; the second neighborhood class is based on the ejection chain idea; and the third neighborhood class exploits the existence of arcs where the vehicle load is zero, giving rise to natural sequences of requests. We report new best results for 16 out of 20 benchmark instances.

B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

transportation
dial-a-ride problem
metaheuristic


Support vector machines versus multi-layer perceptrons for efficient off-line signature recognition The problem of automatic signature recognition has received little attention in comparison with the problem of signature verification despite its potential applications for accessing security-sensitive facilities and for processing certain legal and historical documents. This paper presents an efficient off-line human signature recognition system based on support vector machines (SVM) and compares its performance with a traditional classification technique, multi-layer perceptrons (MLP). In both cases we propose two approaches to the problem: (1) construct each feature vector using a set of global geometric and moment-based characteristics from each signature and (2) construct the feature vector using the bitmap of the corresponding signature. We also present a mechanism to capture the intrapersonal variability of each user using just one original signature. Our results empirically show that SVM, which achieves up to 71% correct recognition rate, outperforms MLP.

B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

multi-layer perceptrons
off-line signature recognition


Chaotic block cryptosystem using high precision approaches to tent map This paper presents the implementation and evaluation of a block cryptosystem based in chaotic maps. The noise function used in this cryptosystem is an approximation to the chaotic tent map, and for this reason, it is named pseudo chaotic tent map (PCT map). PCT map has been analyzed and evaluated using the statistical mechanic tools such as: bifurcation diagram, Lyapunov exponent and invariant distribution. In order to determine the influence of PCT map in the syntactic, semantic and statistic of a message, this map has been used on the non-balanced and dynamic network proposed by Kocarev. Cryptosystem has been evaluated using concepts of the information theory, such as: entropy and mutual information. The randomness of the produced cryptograms has been evaluated using the statistical tests suite of NIST.

O B I O O O O O O O O O O O O O O O O B I O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


interpretable nonnegative matrix decompositions A matrix decomposition expresses a matrix as a product of at least two factor matrices. Equivalently, it expresses each column of the input matrix as a linear combination of the columns in the first factor matrix. The interpretability of the decompositions is a key issue in many data-analysis tasks. We propose two new matrix-decomposition problems: the nonnegative CX and nonnegative CUR problems, that give naturally interpretable factors. They extend the recently-proposed column and column-row based decompositions, and are aimed to be used with nonnegative matrices. Our decompositions represent the input matrix as a nonnegative linear combination of a subset of its columns (or columns and rows). We present two algorithms to solve these problems and provide an extensive experimental evaluation where we assess the quality of our algorithms' results as well as the intuitiveness of nonnegative CX and CUR decompositions. We show that our algorithms return intuitive answers with smaller reconstruction errors than the previously-proposed methods for column and column-row decompositions.

O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

local search
column-row decompositions
alternating least squares


The common randomness capacity of a pair of independent discrete memoryless channels We study the following problem: two agents Alice and Bob are connected to each other by independent discrete memoryless channels, They wish to generate common randomness, i.e., agree on a common random variable, by communicating interactively over the two channels, Assuming that Alice and Bob are allowed access to independent external random sources at rates (in bits per step of communication) of Ha and IIB, respectively, we show that they can generate common randomness at a rate of max{min[H-A + H(W \ Q), I(P; V)] + min[H-B + H(V \ P),I(Q; W)]} bits per step, by exploiting the noise on the two channels, Here, V is the channel from Alice to Bob, and W is the channel from Bob to Alice, The maximum is over all probability distributions P and Q on the input alphabets of V and W, respectively, We also prove a strong converse which establishes the above rate as the highest attainable in this situation.

O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

generating randomness from noise
interactive communication


A genetic algorithm based on extended sequence and topology encoding for the multicast protocol in two-tiered WSN With the rapid evolution of some application technologies in two-tiered wireless sensor network (WSNs), more and more new communication services are emerging quickly, such as multicast video conferencing, retrieval systems and video-on demand, which need the multimedia communication services in multicast mode. Multicast routing is thereby an effective way to communicate among multiple cluster head nodes (CNs) in the network. However, severe energy constraints, Limited link and path constraints make the multicast routing protocol design particularly challenging in WSNs. A fundamental challenge in WSNs is how to maximize network lifetime with regard to a given multicast mission and a certain amount of initial energy provisioning. In this paper, we propose a novel genetic algorithm (GA) based on extended sequence and topology encoding (GAEST) for the multicast protocol in two-tiered WSN. We design power and energy model for GAEST to reasonably adjust CNs Euclid distance according to transmission power calculated by fitness function. To take residual battery energy of CNs and energy balance between CNs into consideration, extended sequence and topology encoding not only holds the T chromosomes which represents the gene topology and records position index of CNs father node, but adds a crucial information for each gene in S chromosomes: the number of CNs children. S-chromosomes crossover of GAEST can change the multicast tree structure drastically and give genetic algorithm the ability of global search to leap from a point in the solution space to a far away point. GAEST improves the mutation process according to Mutation-Replace model, which reasonably swaps the leaf node holding maximum residual energy node with the non-leaf one with the minimum. Simulation results show that GAEST prolongs the lifetime of multicast service compared with Directed Diffused protocol, and increases the packet delivery ratio and fitness value in comparison with GAP, and still obtains the optimal convergence speed from different crossover or mutation probabilities.

O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

two-tiered wireless sensor network (wsns)


Broadcasting in colorless WDM-PON using spectrum-sliced wavelength conversion We propose and experimentally demonstrate a novel wavelength-division-multiplexed passive optical network (WDM-PON) scheme for providing broadcasting service by using an inverted amplified spontaneous emission (ASE) from a semiconductor optical amplifier (SOA). In this scheme, single pump signal is converted into multiple wavelengths signal by spectrum sliced wavelength conversion. We expect it could be very practical and cost-effective solution for broadcasting in WDM-PON due to its simplicity.

B O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O

wdm-pon
cross gain modulation (xgm)
semiconductor optical amplifier (soa)


On the dynamics of capital accumulation across space ? We solve an optimal growth model in continuous space, continuous and bounded time. The optimizer chooses the optimal trajectories of capital and consumption across space and time by maximizing an objective function with both space and time discounting. We extract the corresponding Pontryagin conditions and prove their sufficiency. We end up with a system of two parabolic differential equations with the corresponding boundary conditions. We propose a simple numerical set-up to simulate PDE systems which we employ to study the roles of initial capital and technology distributions over space in various scenarios.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

economic geography
spatial dynamics
optimal control


Matching user requirements in parallel programming While productive use of parallel systems for business applications is quickly growing, their usage for scientific applications is far below expectations. The main reason is that programming of parallel systems is still far too complex. Starting from an analysis of the user requirements, this paper explains our strategy towards next-generation parallel programming environments. We first discuss the problem areas of parallel programming from a user's point of view and give an overview on existing low-, high- and intermediate-level tools. We summarize our objectives and the status of our research. Then we discuss three enabling technologies to overcome current-days limitations of tool environments for parallel computing: formal specification languages, artificial intelligence, and compiler technology. The impact of these technologies on the components proposed for a next-generation programming environment is discussed in detail.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O B I O B I O O O O O O O O O O O O O O O O O O

parallel computing
compiler technology
artificial intelligence

development environment
specification language
user interface
distributed memory
high performance


CapProbe: A simple and accurate capacity estimation technique We present a new capacity estimation technique, called CapProbe. CapProbe combines delay as well as dispersion measurements of packet pairs to filter out samples distorted by cross-traffic. CapProbe algorithms include convergence tests and convergence speed-up techniques by varying probing parameters. Our study of CapProbe includes a probability analysis to determine the time it takes CapProbe to converge on the average. Through simulations and measurements, we found CapProbe to be quick and accurate across a wide range of traffic scenarios. We also compared CapProbe with two previous well-known techniques, pathchar and pathrate. We found CapProbe to be much more accurate than pathchar and similar in accuracy to pathrate, while providing faster estimation than both. Another advantage of CapProbe is its lower computation cost, since no statistical post processing of probing data is required.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

network capacity
bottleneck bandwidth
packet pair dispersion


Change agentry - the next IS frontier We wrote this essay to stimulate IS specialists' efforts to become more effective - and more credible - agents of organizational change. The essay describes what we believe to be a view of the IS specialists' change-agent role that is very commonly held by IS specialists. We believe that this role, while well-intentioned and supported by structural conditions in IS work, often has negative consequences for organizations and for the credibility of IS specialists. Further, it does not fit the emerging structural condition, of IS. We describe two alternative models of what it means to be a change agent, their potential consequences, and the structural conditions that support or inhibit behavior in that role. We conclude that increased behavioral flexibility of IS specialists - the ability to switch roles in different circumstances - would improve organizational effectiveness and IS specialist credibility. Finally, we discuss the implications of our analysis for research, teaching, and practice.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

change management
is function
is personnel
is management
is implementation
is education
future is professionals