Bootstrapping the Interactome: Unsupervised Identification of Protein Complexes in Yeast Protein interactions and complexes are important components of biological systems. Recently, two genome-wide applications of tandem affinity purification (TAP) in yeast have increased significantly the available information on interactions in complexes. Several approaches have been developed to predict protein complexes from these measurements, which generally depend heavily on additional training data in the form of known complexes. In this article, we present an unsupervised algorithm for the identification of protein complexes which is independent of the availability of such additional complex information. Based on a Bootstrap approach, we calculate intuitive confidence scores for interactions more accurate than all other published scoring methods and predict complexes with the same quality as the best supervised predictions. Although there are considerable differences between the Bootstrap and the best published predictions, the set of consistently identified complexes is more than four times as large as for complexes derived from one data set only. Our results illustrate that meaningful and reliable complexes can be determined from the purification experiments alone. As a consequence, the approach presented in this article is easily applicable to large-scale TAP experiments for any species even if few complexes are already known.

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 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

algorithms
computational molecular biology
interactomics


Identifying critical nodes in undirected graphs: Complexity results and polynomial algorithms for the case of bounded treewidth We consider the problem of deleting a limited number of nodes from a graph in order to minimize a connectivity measure of the surviving nodes. We prove that the problem isNP N P -complete even on quite particular types of graphs, and define a dynamic programming recursion that solves the problem in polynomial time when the graph has bounded treewidth. We extend this polynomial algorithm to several variants of the problem.

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 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 O O O O O O O O O O O

treewidth
complexity
dynamic programming


Development a new mutation operator to solve the Traveling Salesman Problem by aid of Genetic Algorithms In this study, a new mutation operator has been developed to increase Genetic Algorithm (GA) performance to find the shortest distance in the known Traveling Salesman Problem (TSP). We called this method as Greedy Sub Tour Mutation (GSTM). There exist two different greedy search methods and a component that provides a distortion in this new operator. The developed GSTM operator was tested with simple GA mutation operators in 14 different TSP examples selected from TSPLIB. The application of this GSTM operator gives much more effective results regarding to the best and average error values. The GSTM operator used with simple GAs decreases the best error values according to the other mutation operators with the ratio of between 74.24% and 88.32% and average error values between 59.42% and 79.51%.

O O O B I O O O B I I 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 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

genetic algorithm
mutation operator
traveling salesman problem


Flexural vibrations of rotating beams considering rotary inertia The effects of rotary inertia on the extensional tensile force and on the eigenvalues of beams rotating uniformly about a transverse axis taking into account longitudinal elasticity are analyzed in this work using the perturbation technique and Galerkin's method. A simple relation for the extensional tensile force is determined that is useful for the design of rotating beams. For a typical helicopter rotor blade, it is shown that the extensional tensile force increases by up to 10% if the rotary inertia contribution is retained in the analysis.

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

vibrations
rotating beams
rotary inertia

longitudinal vibration
flexural vibration
blade vibration


Local search with edge weighting and configuration checking heuristics for minimum vertex cover The Minimum Vertex Cover (MVC) problem is a well-known combinatorial optimization problem of great importance in theory and applications. In recent years, local search has been shown to be an effective and promising approach to solve hard problems, such as MVC. In this paper, we introduce two new local search algorithms for MVC, called EWLS (Edge Weighting Local Search) and EWCC (Edge Weighting Configuration Checking). The first algorithm EWLS is an iterated local search algorithm that works with a partial vertex cover, and utilizes an edge weighting scheme which updates edge weights when getting stuck in local optima. Nevertheless, EWLS has an instance-dependent parameter. Further, we propose a strategy called Configuration Checking for handling the cycling problem in local search. This is used in designing a more efficient algorithm that has no instance-dependent parameters, which is referred to as EWCC. Unlike previous vertex-based heuristics, the configuration checking strategy considers the induced subgraph configurations when selecting a vertex to add into the current candidate solution. A detailed experimental study is carried out using the well-known DIMACS and BHOSLIB benchmarks. The experimental results conclude that EWLS and EWCC are largely competitive on DIMACS benchmarks, where they outperform other current best heuristic algorithms on most hard instances, and dominate on the hard random BHOSLIB benchmarks. Moreover, EWCC makes a significant improvement over EWLS, while both EWLS and EWCC set a new record on a twenty-year challenge instance. Further. EWCC performs quite well even on structured instances in comparison to the best exact algorithm we know. We also study the run-time behavior of EWLS and EWCC which shows interesting properties of both algorithms. (C) 2011 Elsevier B.V. All rights reserved.

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

minimum vertex cover
local search
edge weighting
configuration checking


Experimental analysis of a solar PV/diesel hybrid system without storage: Focus on its dynamic behavior Integration of solar photovoltaic systems with diesel generators for the electrification of remote and rural areas would assist in expanding the electricity access in the sub-Saharan Africa region. In fact, countries of this region are well endowed in solar resource: their mean daily solar radiation exceeds 5.5kWh/m2/day. They are, therefore, good locations for PV systems. This paper deals with an experimental study of the dynamic behavior of a hybrid system prototype (based on flexy-energy concept) set up at Kamboins, located at 15km far from Ouagadougou (12, 22 N and 1, 31 W) in Burkina Faso. The prototype is composed of a 2.85kWp PV array, a 3.3kW single phase inverter and a diesel generator rated at 9.2kW. Two resistive load banks of about 4kW each are used to simulate the load profiles. Experimental results show that the PV generation leads the distribution feeder to shift toward higher voltages. The voltage rise is exacerbated when the PV generation is at its highest and the demand at its lowest. Care should then be taken to ensure that for a hybrid PV/diesel system, the PV rated power connected to each phase of the diesel generator is as equal as possible. The present study also points out that well designed inverters generate very small voltage harmonics and current distortions, even when high PV penetration systems are considered.

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

inverter technology
voltage regulation
harmonic distortion
flexy-energy


Sub-part correspondence by structural descriptors of 3D shapes To fully exploit the valuable knowledge embedded in repositories of digital models, it is crucial to devise search engines capable of expressing high-level and advanced queries, which can effectively support the re-use of CAD models. The retrieval mechanism should be able to return not only global similarity measures among objects, but it should also be coupled with methods for the automatic identification of similar sub-parts in the query and retrieved models, possibly highlighting automatically the object differences. This paper describes a method for partial shape-matching able to recognize similar sub-parts of objects represented as 3D polygonal meshes. The geometry and the structure of the shapes are coupled in a descriptor that provides a flexible coding, grounded on solid mathematical theories, and that can be adapted to the users needs and to the context of applications. The matching framework for sub-part correspondence is achieved through a graph-matching technique, which builds the common sub-graphs between the two shapes and highlights the maximal sub-parts having similar structure and similar space distribution.

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

shape similarity
sub-part shape correspondence
structural shape descriptor
graph matching


Applying successive improvement transformations for intelligent problem solving An improvement transformation is a transformation which has the following two properties, namely, (1) after applying it, all the already achieved subgoals are still being accomplished and (2) additional new subgoals or partial new subgoals may be accomplished. By using improvement transformations, an intelligent problem-solving method is presented with illustrative examples. This method consists of three parts: (1) goal decomposition and subgoal ordering; (2) successive improvement transformations; and (3) backtrack algorithms. The intelligent problem-solving method using successive improvement transformations may have useful applications in goal decomposition, goal regression, genetic algorithms, robotics, and future expert system design.

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


A Bayesian Approach for System Reliability Analysis With Multilevel Pass-Fail, Lifetime and Degradation Data Sets Reliability analysis of complex systems is a critical issue in reliability engineering. Motivated by practical needs, this paper investigates a Bayesian approach for system reliability assessment and prediction with multilevel heterogeneous data sets. Two major imperatives have been handled in the proposed approach, which provides a comprehensive Bayesian framework for the integration of multilevel heterogeneous data sets. In particular, the pass-fail data, lifetime data, and degradation data at different system levels are combined coherently for system reliability analysis. This approach goes beyond the alternatives that deal with solely multilevel pass-fail or lifetime data, and presents a more practical tool for real engineering applications. In addition, the indices for reliability assessment and prediction are constructed coherently within the proposed Bayesian framework. It gives rise to a natural manner of incorporating this approach into a decision-making procedure for system operation and management. The effectiveness of the proposed approach is illustrated with reliability analysis of a navigation satellite.

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

multilevel heterogeneous data sets (mhds)


A simulation framework for technical systems life cycle cost analysis This paper deals with the construction of a simulation framework for technical systems life cycle cost (LCC) analysis. It also deals with the concept of software reuse in event-based simulation, since the framework involves simulation of all cost generating activities related to a technical system, from its planning and acquisition phases until its final discard. The basic principles of object-oriented programming and simulation software efficiency, reuse, extensibility and evolvability are analyzed and the concepts of computational reflection and frameworks are explored. Finally, the framework is described in detail and its extension points, based on the inheritance mechanism, are shown.

O B I O O O B I I 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 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

simulation framework
software reuse
life cycle cost analysis


Visualizing genomic information across chromosomes with PhenoGram With the abundance of information and analysis results being collected for genetic loci, user-friendly and flexible data visualization approaches can inform and improve the analysis and dissemination of these data. A chromosomal ideogram is an idealized graphic representation of chromosomes. Ideograms can be combined with overlaid points, lines, and/or shapes, to provide summary information from studies of various kinds, such as genome-wide association studies or phenome-wide association studies, coupled with genomic location information. To facilitate visualizing varied data in multiple ways using ideograms, we have developed a flexible software tool called PhenoGram which exists as a web-based tool and also a command-line program.

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

bioinformatics
genome-wide association study
gwas
copy-number variants
cnv
snp


Evolving neural network for printed circuit board sales forecasting Printed circuit board industry plays an important role in Taiwan's economy, but severe inventory stacking and material lacking problems still exist. However, the occurrence of these problems is likely to be decreased via establishing an accurate demand forecasting system. Thus, an Evolving Neural Network (ENN) forecasting model by integrating Genetic Algorithms and Neural Network is developed in this research. Along with trend and seasonal factors considered by Winter's model, effective economical factors are chosen by the Grey Relation Analysis. The numerical data of these factors and actual demand of the past 5 years are input into the training stage of ENN, while the comparison with other models is evaluated on testing stage. The experimental result shows that the performance of ENN is superior to traditional statistical models and Back Propagation Network. The ENN provides a promising solution to the forecasting problem for relevant industries.

O B I O B I I B I 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 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

sales forecasting
printed circuit board
neural network


Characterizing user tagging and Co-occurring metadata in general and specialized metadata collections This study aims to identify the categorical characteristics and usage patterns of the most popular image tags in Flickr. The metadata usage ratio is introduced as a means of assessing the usage of a popular tag as metadata. We also compare how popular tags are used as image tags or metadata in the Flickr general collection and the Library of Congress's photostream (LCP), also in Flickr. The Flickr popular tags in the list overall are categorically stable, and the changes that do appear reflect Flickr users' evolving technology-driven cultural experience. The popular tags in Flickr had a high number of generic objects and specific locations-related tags and were rarely at the abstract level. Conversely, the popular tags in the LCP describe more in the specific objects and time categories. Flickr users copied the Library of Congress-supplied metadata that related to specific objects or events and standard bibliographic information (e.g., author, format, time references) as popular tags in the LCP. Those popular tags related to generic objects and events showed a high metadata usage ratio, while those related to specific locations and objects showed a low image metadata usage ratio. Popular tags in Flickr appeared less frequently as image metadata when describing specific objects than specific times and locations for historical images in Flickr LCP collections. Understanding how people contribute image tags or image metadata in Flickr helps determine what users need to describe and query images, and could help improve image browsing and retrieval.

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

image analysis
image enhancement
imaging


Property-preserving data reconstruction We initiate a new line of investigation into online property-preserving data reconstruction. Consider a dataset which is assumed to satisfy various (known) structural properties; e.g., it may consist of sorted numbers, or points on a manifold, or vectors in a polyhedral cone, or codewords from an error-correcting code. Because of noise and errors, however, an (unknown) fraction of the data is deemed unsound, i.e., in violation with the expected structural properties. Can one still query into the dataset in an online fashion and be provided data that is always sound? In other words, can one design a filter which, when given a query to any item I in the dataset, returns a sound item J that, although not necessarily in the dataset, differs from I as infrequently as possible. No preprocessing should be allowed and queries should be answered online. We consider the case of a monotone function. Specifically, the dataset encodes a function f:{1,...,n} (bar right arrow) R that is at (unknown) distance epsilon from monotone, meaning that f can-and must-be modified at epsilon n places to become monotone. Our main result is a randomized filter that can answer any query in O(log(2) n log log n) time while modifying the function f at only O(epsilon n) places. The amortized time over n function evaluations is O(log n). The filter works as stated with probability arbitrarily close to 1. We provide an alternative filter with O(log n) worst case query time and O(epsilon n log n) function modifications. For reconstructing d-dimensional monotone functions of the form f:{1,...,n}(d) (bar right arrow) R, we present a filter that takes (2(O(d))(log n)(4d-2) log log n) time per query and modifies at most O(epsilon n(d)) function values (for constant d).

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

sublinear algorithms
monotonicity testing


cross-lingual relevance models We propose a formal model of Cross-Language Information Retrieval that does not rely on either query translation or document translation. Our approach leverages recent advances in language modeling to directly estimate an accurate topic model in the target language, starting with a query in the source language. The model integrates popular techniques of disambiguation and query expansion in a unified formal framework. We describe how the topic model can be estimated with either a parallel corpus or a dictionary. We test the framework by constructing Chinese topic models from English queries and using them in the CLIR task of TREC9. The model achieves performance around 95\% of the strong mono-lingual baseline in terms of average precision. In initial precision, our model outperforms the mono-lingual baseline by 20\%. The main contribution of this work is the unified formal model which integrates techniques that are essential for effective Cross-Language Retrieval.

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

framework
translation
task
test
parallel
language
performance
retrieval
queries
relevance
topic model
model
query

precise
estimates
language models
formalism
query-expansion
dictionaries
cross-language information retrieval
formal models
language modelling
documentation
effect


Non-negative matrix completion for action detection ? Developing a multi-label classification framework with a convex optimization process for activity detection. Histogram correction for activity representation in each class, to localize activities in a weakly supervised setting. Proposing a new formulation for matrix completion to deal with classification/localization in video. Developing an activity recognition system in a totally weakly supervised multi-label setting. Developing a non-negative matrix completion framework based on Alternating Direction Method (ADM).

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 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 B I I O

matrix completion
alternating direction method
convex optimization

multi-label classification
weakly supervised classification
human activity recognition


Derivation of cable parameters for a reduced model that retains asymmetric voltage attenuation of reconstructed spinal motor neuron dendrites Spinal motor neurons have voltage gated ion channels localized in their dendrites that generate plateau potentials. The physical separation of ion channels for spiking from plateau generating channels can result in nonlinear bistable firing patterns. The physical separation and geometry of the dendrites results in asymmetric coupling between dendrites and soma that has not been addressed in reduced models of nonlinear phenomena in motor neurons. We measured voltage attenuation properties of six anatomically reconstructed and type-identified cat spinal motor neurons to characterize asymmetric coupling between the dendrites and soma. We showed that the voltage attenuation at any distance from the soma was direction-dependent and could be described as a function of the input resistance at the soma. An analytical solution for the lumped cable parameters in a two-compartment model was derived based on this finding. This is the first two-compartment modeling approach that directly derived lumped cable parameters from the geometrical and passive electrical properties of anatomically reconstructed neurons.

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

membrane potential
spinal cord
bistability
plateau potential


mining search engine query logs for query recommendation This paper presents a simple and intuitive method for mining search engine query logs to get fast query recommendations on a large scale industrial strength search engine. In order to get a more comprehensive solution, we combine two methods together. On the one hand, we study and model search engine users' sequential search behavior, and interpret this consecutive search behavior as client-side query refinement, that should form the basis for the search engine's own query refinement process. On the other hand, we combine this method with a traditional content based similarity method to compensate for the high sparsity of real query log data, and more specifically, the shortness of most query sessions. To evaluate our method, we use one hundred day worth query logs from SINA' search engine to do off-line mining. Then we analyze three independent editors evaluations on a query test set. Based on their judgement, our method was found to be effective for finding related queries, despite its simplicity. In addition to the subjective editors' rating, we also perform tests based on actual anonymous user search sessions.

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

mining
query logs
recommendation
order
use
method
users
search engine
test
industrial
behavior
data
process
queries
similarity
paper
model
user
search
query

large-scale session anonymity refine effect evaluation


Microarchitectural Transformations Using Elasticity Elasticity is a paradigm that tolerates the variations in computation and communication delays. By applying elastic transformations that allow varying the original timing, circuits can be optimized beyond the conventional rigid transformations that do not modify the external timing. Pipelining is one of the classical techniques to improve the throughput of a circuit. This article reveals how elasticity can be effectively and practically used to derive pipelined circuits by using correct-by-construction transformations that can be fully automated. Two designs, one of them industrial, are used to demonstrate how the area-performance trade-off can be explored using elasticity.

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

design
performance
elastic circuits
asynchronous circuits
latency insensitivity


efficient selection algorithms on distributed memory computers Consider the selection problem of determining the k th smallest element of a sequence of n elements. Under the CGM (Coarse Grained Multicomputer) model with p processors and O ( n/p ) local memory, we present a deterministic parallel algorithm for the selection problem that requires O (log p ) communication rounds. Besides requiring a low number of communication rounds, the algorithm also attempts to minimize the total amount of data transmitted in each round (only O ( p ) except in the last round). The basic algorithm is then extended to solve the problem of q simultaneous selections using the same input sequence, also in O (log p ) communication rounds and asymptotically same local computing time (if q = O ( p ) ). The simultaneous selection algorithm gives rise to a communication efficient sorting algorithm, with O (log p ) communication rounds and a total of O ( p 2 ) data transmitted in each round except in the last one. In addition to showing theoretical complexities, we present very promising experimental results obtained on two parallel machines that show almost linear speedup, indicating the efficiency and scalability of the proposed algorithms. To our knowledge, this is the best deterministic CGM algorithm in the literature for the selection problem.

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 B I I 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 B I 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 B I

sorting
coarse grained multicomputer
selection problem
parallel algorithm
simultaneous selection


Scalable Fluid Simulation using Anisotropic Turbulence Particles It is usually difficult to resolve the fine details of turbulent flows, especially when targeting real-time applications. We present a novel, scalable turbulence method that uses a realistic energy model and an efficient particle representation that allows for the accurate and robust simulation of small-scale detail. We compute transport of turbulent energy using a complete two-equation k-epsilon model with accurate production terms that allows us to capture anisotropic turbulence effects, which integrate smoothly into the base flow. We only require a very low grid resolution to resolve the underlying base flow. As we offload complexity from the fluid solver to the particle system, we can control the detail of the simulation easily by adjusting the number of particles, without changing the large scale behavior. In addition, no computations are wasted on areas that are not visible. We demonstrate that due to the design of our algorithm it is highly suitable for massively parallel architectures, and is able to generate detailed turbulent simulations with millions of particles at high framerates.

O B I 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 O O O O 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


New Genetic Insights in Familial Hyperaldosteronism Aldosterone, the major circulating mineralocorticoid, particiates in blood volume and serum potassium homeostasis. Primary aldosteronism is a disorder characterized by hypertension and, in more severe form, hypokalemia, due to autonomous aldosterone secretion from the adrenocortical zona glomerulosa. Improved screening techniques, particularly application of the plasma aldosterone

O O O O B 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


CORAL: Predictions of rate constants of hydroxyl radical reaction using representation of the molecular structure obtained by combination of SMILES and Graph approaches New version of CORAL software is now available on the Internet (http://www.insilico.eu/CORAL/). Previous versions of this software built up a quantitative structure-property/activity relationships (QSPR/QSAR) based on representation of the molecular structure by the simplified molecular input line entry system (SMILES). The present study has shown that the novel 'hybrid' representation of molecular structure by combination of SMILES and the molecular graph can improve the predictive potential of CORAL models. The evaluation of this approach has been performed for a large (n = 460) set of heterogeneous organic compounds. The tested endpoint represent rate constants of hydroxyl radical reaction of polybrominated diphenyl ethers and (benzo-)triazoles. (c) 2011 Elsevier B.V. All rights reserved.

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


A compliance based design problem of structures under multiple load cases There are two popular methods concerning the optimal design of structures. The first is the minimization of the volume of the structure under stress constraints. The second is the minimization of the compliance for a given volume. For multiple load cases an arising issue is which energy quantity should be the objective function. Regarding the sizing optimization of trusses, Rozvany proved that the solution of the established compliance based problems leads to results which are awkward and not equivalent to the solutions of minimization of the volume under stress constraints, unlike under single loading (the layouts would be the same if in the compliance problem the volume is set equal to the result of the first problem). In this paper, we introduce the "envelope strain energy" problem where we minimize the volume integral of the worst case strain energy of each point of the structure. We also prove that in the case of sizing optimization of statically non-indeterminate (the term non-indeterminate includes both statically determinate trusses and mechanisms) trusses, this compliance method gives the same optimal design as the stress based design method.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O 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
truss optimization
compliance methods
envelope strain energy method
stress based methods


game theoretic power allocation in sparsely distributed clusters of wireless sensors (gpas) Sparsely distributed clusters of wireless sensors with applications ranging from state-wide wireless bridge monitoring to animal herds tracking have gained recent attention due to their special characteristics and challenging resource allocation problem. A novel optimal power allocation paradigm based on game theory is proposed to minimize the inter and intra-cluster interference. Cost functions are assigned to the transmission power, estimate of the aggregate interference generated by the cluster on the overall network, and the signal to interference and noise ratio (SINR) at the node level. It is observed that the proposed algorithm demonstrates acceptable convergence properties when used after a channel allocation scheme and is more power efficient if used in parallel with a channel allocation method. Simulation results are presented to support the proposed analysis.

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

wireless sensor networks
sparse distributions
interference mitigation
power minimization


Evaluating the relationship between chemical exposure and cryptorchidism One method for the evaluation of complex environmental and health datasets is the discrete mathematical method Hasse diagram technique based on partial orders. The introduced software program package is named PyHasse. In this paper we evaluate a possible human association between maternal exposure to organochlorine compounds used as pesticides and cryptorchidism among male children in Finland and Denmark. We identified differences in comparable and incomparable objects and quantified these differences by the software tool Similarity Analysis in the program PyHasse. Furthermore we interpreted the corresponding Hasse diagrams concerning chosen striking objects. We found the position of the chemicals AHCH (alpha-Hexachlorohexane), CHCE (cis-Heptachloroepoxide), DIEL (Dieldrin), and MIRE (Mirex) has some influence on the differentiation of the Hasse diagrams and hence of each two datasets analyzed. The largest disparities can be observed when we compare the Finnish and Danish datasets concerning cryptorchidism. The disparities are demonstrated in the corresponding Hasse diagrams.

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 I 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 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 O O O O O O O O O O O O O O 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

cryptorchidism
hasse diagram technique
pyhasse

environmental health data
partially ordered sets
environmental software


load balancing using work-stealing for pipeline parallelism in emerging applications Parallel programming is a requirement in the multi-core era. One of the most promising techniques to make parallel programming available for general users is the use of parallel programming patterns. Functional pipeline parallelism is a well suited pattern for many emerging applications, such as streaming and "Recognition, Mining and Synthesis" (RMS) workloads. In this paper we develop an analytical model for pipeline parallelism and use it to characterize and optimize two of the PARSEC benchmarks which use the parallel pipeline pattern, ferret and dedup . We identify two scalability limitations: load imbalance and I/O bottlenecks. We address load imbalance using two techniques: parallel pipeline stage collapsing and dynamic scheduling. We implemented these optimizations using Pthreads and the Threading Building Blocks (TBB) libraries. We compare predicted and measured performance of all these implementations on a large scale SMP machine and we note that the work-stealing TBB implementation outperforms all other variants.

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


J3DV: A Java-based 3D database visualization tool Database visualization helps users process, interpret and act upon large stored data sets. In this paper, we present a Java-based 3D database visualization tool called J3DV. The J3DV tool successfully solved the problem of data management faced by many other visualization systems by integrating multiple data sources with the visualization tool. The tool utilizes two-level mapping to transform the data into intermediate data that can be used to render graphs. Intermediate data offers better performance with a two-tier cache. This visualization tool presents a sound framework, which has good extensibility for plugging in new data sources, supporting new data models and visual presentation types and allowing new graph layout algorithms. Copyright (C) 2002 John Wiley Sons, Ltd.

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 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

data models mapping
java 3d
bioinformatics
protein-protein interaction mapping


A Simpler Linear-Time Recognition of Circular-Arc Graphs We give a linear-time recognition algorithm for circular-arc graphs based on the algorithm of Eschen and Spinrad (Proceedings of the Fourth Annual ACM-SIAM Symposium on Discrete Algorithms (SODA), pp. 128-137, 1993) and Eschen (PhD thesis, 1997). Our algorithm both improves the time bound of Eschen and Spinrad, and fixes some flaws in it. Our algorithm is simpler than the earlier linear-time recognition algorithm of McConnell (Algorithmica 37(2):93-147, 2003), which is the only linear time recognition algorithm previously known.

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

circular-arc graph
circular-arc model
intersection graph
consecutive-ones property


Gesture recognition using Bezier curves for visualization navigation from registered 3-D data ? This paper presents a gesture recognition system for visualization navigation. Scientists are interested in developing interactive settings for exploring large data sets in an intuitive environment. The input consists of registered 3-D data. A geometric method using Bezier curves is used for the trajectory analysis and classification of gestures. The hand gesture speed is incorporated into the algorithm to enable correct recognition from trajectories with variations in hand speed. The method is robust and reliable: correct hand identification rate is 99.9% (from 1641 frames), modes of hand movements are correct 95.6% of the time, recognition rate (given the right mode) is 97.9%. An application to gesture-controlled visualization of 3D bioinformatics data is also presented.

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

gesture recognition system
bezier curves
visualization navigation

motion analysis
hand tracking
human-computer interaction
region detection and identification
3-d trajectory analysis


Improved structure for adiabatic CMOS circuits design Two adiabatic circuits with complementary structure and operation are proposed in this paper. They employ two-phase sinusoidal power clock. The power consumption of the proposed circuits is comparable to that of some previously reported circuits. The problem of floating output nodes is solved by connecting two MOS transistors to the power clock. In particular, using the proposed architecture more than one stage of gates can be computed simultaneously within a single clock-phase, compared to only one stage is computed in every phase by most other adiabatic logic families. With this feature, the latency of the complex logic circuit is greatly improved and the number of buffers required for a pipelining circuit is also reduced. In this paper, a 2:1 multiplexer and full adder are illustrated and simulated. From the PSPICE simulation results, the effectiveness of the proposed approach and the low power characteristic of the designed circuits are validated.

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

low power design technique
energy recovery


Beyond the monomiality: the monumbrality principle The monomiality principle has allowed the derivation, in a fairly straightforward way, of the properties of many families of special polynomials, recognized as quasi monomials. The family of quasimonomials is large, but not all the special polynomials can be framed within this category. In this paper we will prove the existence of a larger family, including the quasi-monomials, by taking advantage from the umbral calculus and by introducing the concept of monumbrality, which appears very useful to get a deeper understanding in the nature and role of special polynomials.

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 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 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

monomiality principle
monumbrality principle
umbral calculus
special polynomials


Failover, load sharing and server architecture in SIP telephony We apply some of the existing web server redundancy techniques for high service availability and scalability to the relatively new IP telephony context. The paper compares various failover and load sharing methods for registration and call routing servers based on the Session Initiation Protocol (SIP). In particular, we consider SIP server failover techniques based on the clients, DNS (Domain Name Service), database replication and IP address takeover, and load sharing techniques using DNS, SIP identifiers, network address translators, and servers with same IP addresses. We describe our two-stage reliable and scalable SIP server architecture in which the first stage proxies the request to one of the second stage server group based on the destination user identifier. We quantitatively evaluate the performance improvement of the load sharing architecture using our SIP server. We quantitatively compare the effect of SIP server architecture such as event-based and thread pool. Additionally, we present an overview of the failover mechanism we implemented in our test-bed using the open source MySQL database. (c) 2006 Elsevier B.V. All rights reserved.

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

availability
scalability
failover
load sharing
sip


A level set approach for dilute non-collisional fluid-particle flows Gas-particle and other dispersed-phase flows can be described by a kinetic equation containing terms for spatial transport, acceleration, and particle processes (such as evaporation or collisions). However, computing the dispersed velocity is a challenging task due to the large number of independent variables. A level set approach for computing dilute non-collisional fluid-particle flows is presented. We will consider the sprays governed by the Williams kinetic equation subject to initial distributions away from equilibrium of the form ? i = 1 N ? i ( x ) ? ( ? - u i ( x ) ) . The dispersed velocity is described as the zero level set of a smooth function, which satisfies a transport equation. This together with the density weight recovers the particle distribution at any time. Moments of any desired order can be evaluated by a quadrature formula involving the level set function and the density weight. It is shown that the method can successfully handle highly non-equilibrium flows (e.g. impinging particle jets, jet crossing, particle rebound off walls, finite Stokes number flows).

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

level set method
kinetic equations
fluid particle fluids


Extending knowledge-driven activity models through data-driven learning techniques We combine knowledge- and data-driven approaches for activity modeling. We develop a novel clustering algorithm that uses prior domain expert knowledge. A new learning algorithm to model activities from extracted clusters. We model a pervasive home environment with real users inputs for experiments. Automatically learn 100% of activity variations performed by users.

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 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

activity recognition
knowledge-driven
activity model


Passivity analysis of discrete-time stochastic neural networks with time-varying delays ? In this paper, the problem of passivity analysis is investigated for a class of discrete-time stochastic neural networks with time-varying delays. For the neural networks under study, a generalized activation function is considered, where the traditional assumptions on the boundedness, monotony and differentiability of the activation functions are removed. By constructing proper LyapunovKrasovskii functional and employing a combination of the free-weighting matrix method and stochastic analysis technique, a delay-dependent passivity condition is derived in terms of linear matrix inequalities (LMIs). Furthermore, when the parameter uncertainties appear in the discrete-time stochastic neural networks with time-varying delays, a delay-dependent robust passivity condition is also presented. An example is given to show the effectiveness of the proposed criterion.

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

discrete-time neural network
time-varying delays
robust passivity


Low-voltage process-insensitive frequency compensation method for two-stage OTA with enhanced DC gain A proposed low-voltage pseudo-cascode frequency compensation technique to improve the phase-margin of the two-stage OTA in weak-inversion region is introduced. Furthermore, a enhanced composite-transistor technique to increase the DC gain of the two-stage OTA in weak-inversion region is also presented in this paper. Both the proposed techniques achieve enhanced performance without requiring any additional power dissipation. To compare the performance advantages of the proposed techniques, two two-stage OTAs were designed in a UMC 0.18?m CMOS process. Simulation results show that the DC gain of the two-stage OTA with enhanced composite-transistor is increased by a factor of 17dB, the unity-gain bandwidth of the OTA with the proposed pseudo-cascode compensation technique improved 18%, the phase-margin of the OTA is increased by 33%, and it is maintained over a factor of 300 (from 5 to 1500nA) scaling in its bias current.

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

gain enhancement
two-stage ota
low voltage
process insensitive


constructivist physics learning in an immersive, multi-user hot air balloon simulation program (ihabs) This paper describes and discusses an immersive multi-user Hot Air Balloon Simulation (iHABS) project that allows students to experience virtual hot air ballooning. The iHABS project enables students to pilot a hot air balloon as well as learn fundamental physics principles in a fun, exciting, engaging, and collaborative setting.We briefly survey the use of hot air ballooning in physics teaching and the use of VR technologies in support of learning. We then discuss the pedagogical support provided by iHABS. Next, we proceed with a detailed description of the iHABS system followed by a discussion on the design of interaction techniques, the system design and its implementation.

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


Optical-LSP establishment and a QoS maintenance scheme based on differentiated optical QoS classes in OVPNs A "virtual private network (VPN) over Internet" has the benefit of being cost-effective and flexible. However, it has difficulties providing sufficient QoS and adequate transmission capacity for high bandwidth services. Given the increasing demand for high bandwidth Internet and the demand for QoS assurances in a "VPN over Internet", IP/generalized multi-protocol label switching (GMPLS) based on a control plane combined with a high-bandwidth, dense-wavelength division multiplexing (DWDM) optical network is seen as a very favorable approach for realizing the future "optical VPN (OVPN) over lP/GMPLS over DWDM". Within this architecture, providing QoS guaranteed multimedia services with a differentiated QoS guaranteed protocol framework with QoS recovery is one of the key issues to implement. Therefore, we suggest in this paper optical-label switched path (O-LSP) establishment and its QoS maintenance scheme based on differentiated optical QoS-service (DOQoS) classes. They are the key components for this DOQoS framework in assuring end-to-end QoS in an "OVPN over lP/GMPLS over DWDM" architecture.

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


Monocular Template-based Reconstruction of Inextensible Surfaces We present a monocular 3D reconstruction algorithm for inextensible deformable surfaces. It uses point correspondences between a single image of the deformed surface taken by a camera with known intrinsic parameters and a template. The main assumption we make is that the surface shape as seen in the template is known. Since the surface is inextensible, its deformations are isometric to the template. We exploit the distance preservation constraints to recover the 3D surface shape as seen in the image. Though the distance preservation constraints have already been investigated in the literature, we propose a new way to handle them. Spatial smoothness priors are easily incorporated, as well as temporal smoothness priors in the case of reconstruction from a video. The reconstruction can be used for 3D augmented reality purposes thanks to a fast implementation. We report results on synthetic and real data. Some of them are compared to stereo-based 3D reconstructions to demonstrate the efficiency of our method.

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

3d reconstruction
surface
deformable
template


A problem-solving method for "unprotocolised' therapy administration task in medicine This paper describes a problem-solving method for modelling the 'unprotocolised' treat ment administration task in medicine. We argue that there are medical domains in which no well-established standard treatment protocols exist, and the physician has to decide on the therapy that is to be applied to each patient, in function of a set of therapeutic objectives to be fulfilled. For this reason, we propose the modelling of this type of task adapting the generic class of problem resolution methods for design task, labelled as Propose-Critique-Modify (PCM). In this paper, we are presenting a model of expertise which has been developed using the basic modelling components of the CommonKADS methodology. (C) 1999 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 O O O O O O 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

problem-solving method
model of expertise model
protocol-based decision support systems


Constructing a logic of plausible inference: a guide to Cox's theorem Cox's theorem provides a theoretical basis for using probability theory as a general logic of plausible inference. The theorem states that any system for plausible reasoning that satisfies certain qualitative requirements intended to ensure consistency with classical deductive logic and correspondence with commonsense reasoning is isomorphic to probability theory. However, the requirements used to obtain this result have been the subject of much debate. We review Cox's theorem, discussing its requirements, the intuition and reasoning behind these, and the most important objections, and finish with an abbreviated proof of the theorem. (C) 2003 Elsevier Inc. All rights reserved.

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 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


An ALE finite element method for a coupled Stefan problem and NavierStokes equations with free capillary surface In this article, an ALE finite element method to simulate the partial melting of a workpiece of metal is presented. The model includes the heat transport in both the solid and liquid part, fluid flow in the liquid phase by the NavierStokes equations, tracking of the melt interface solid/liquid by the Stefan condition, treatment of the capillary boundary accounting for surface tension effects and a radiative boundary condition.We show that an accurate treatment of the moving boundaries is crucial to resolve their respective influences on the flow field and thus on the overall energy transport correctly. This is achieved by a mesh-moving method, which explicitly tracks the phase boundary and makes it possible to use a sharp interface model without singularities in the boundary conditions at the triple junction.A numerical example describing the welding of a thin-steel wire end by a laser, where all aforementioned effects have to be taken into account, proves the effectiveness of the approach.Copyright (c) 2012 John Wiley & Sons, Ltd.

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

navierstokes
stefan problem
free capillary surface

ale formulation
mesh-moving
decoupling strategy


Convergence studies on iterative algorithms for image reconstruction We introduce a general iterative scheme for image reconstruction based on Landweber's method. In our configuration, a sequential block-iterative (SeqBI) version can be readily formulated from a simultaneous block-iterative (SimBI) version, and vice versa. This provides a mechanism to derive new algorithms from known ones. It is shown that some widely used iterative algorithms, such as the algebraic reconstruction technique (ART), simultaneous ART (SART), Cimmino's, and the recently designed diagonal weighting and component averaging algorithms, are special examples of the general scheme. We prove convergence of the general scheme under conditions more general than assumed in earlier studies, for its SeqBI and SimBI versions in the consistent and inconsistent cases, respectively. Our results suggest automatic relaxation strategies for the SeqBI and SimBI versions and characterize the dependence of the limit image on the initial guess. It is found that in all cases the limit is the sum of the minimum norm solution of a weighted least-squares problem and an oblique projection of the initial image onto the null space of the system matrix.

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

sequential block-iterative
simultaneous block-iterative
weighted least-squares


Quadrature using 64-bit IEEE arithmetic for integrands over [0,1] with a singularity at 1 We present a detailed study of some problems encountered when quadrature over 10, 11 is attempted with integrands that have a singularity at 1. Methods designed to increase the accuracy of such quadratures, for example, the application of periodising transformations, are examined in the context of the representational limitations of 64-bit IEEE arithmetic near 1 in [0.1]. A heuristic is proposed for the forecasting of a lower bound on the irremovable error due to these limitations. We conclude by affirming the commonly accepted procedure that where possible, integrals should be symbolically transformed so that my remaining singularity occurs at 0. (c) 2005 Elsevier 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 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

automatic quadrature
64-bit ieee arithmetic
extrapolation


An efficient multiple shooting based reduced SQP strategy for large-scale dynamic process optimization - Part II: Software aspects and applications As model based optimization techniques play a more and more important role in the chemical process industries, there is a great demand for ever more efficient and reliable process optimization software. In the first part of this paper, the theoretical aspects of a tailored multiple shooting based solution strategy for dynamic process optimization have been presented (Leineweber, Bauer, Bock & Schloder, 2002. An efficient multiple shooting based reduced SQP strategy for large-scale dynamic process optimization-part 1: theoretical aspects). The current second part describes software aspects of the specific implementation muscod-ii and provides numerical results for several application examples. muscod-ii has been coupled with the dynamic process modeling software gPROMS via the standard equation set object (ESO) interface of CAPE-OPEN. Thereby, an advanced dynamic optimization platform for integrated batch processes has been created, where each process stage is separately modeled in gPROMS, and the multistage dynamic optimization problem is assembled and solved with MUSCOD-II. The code has also been parallelized. based on the portable MPI standard. It is shown that the use of directional sensitivities becomes very important for larger problems with many algebraic variables, leading to drastically reduced computing times compared with strategies with complete constraint linearization. In addition, gPROMS ESO models are compared with classical Fortran models in terms of computational performance, and it is found that only a moderate loss of performance occurs if so-called in-process ESOs are employed. Finally, it is demonstrated that a significant speed-up can be obtained through parallel function and gradient evaluations. (C) 2002 Published by Elsevier Science Ltd.

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 B I 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 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 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

multiple shooting
directional sensitivities
integrated batch processes

dynamic optimization software
cape-open standard
equation set object (eso)
structured rsqp methods
multistage optimal control problems
parallel computing


Stratified order one differential equations in positive characteristic Stratification for nonlinear differential equations in positive characteristic is introduced. Testing this notion for first order equations is discussed, and related to the Cartier operator on curves. A variant of the GrothendieckKatz conjecture is formulated, and proved in a special case.

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


Saying the wrong thing: improving learning with multimedia by including misconceptions Abstract In this study, 364 first-year physics students were randomly assigned to one of four online multimedia treatments on Newton's First and Second Laws of Motion: (1) the Exposition, a concise lecture-style presentation; (2) the Extended Exposition, the Exposition with additional interesting information; (3) the Refutation, the Exposition with common misconceptions explicitly stated and refuted; or (4) the Dialogue, a studenttutor discussion of the same material as in the Refutation. Students were tested using questions from mechanics conceptual inventories before and after watching the multimedia treatments. Results show the Refutation and Dialogue produced the greatest learning gains, with effect sizes of 0.79 and 0.83, respectively, compared with the Exposition. Students with low prior knowledge benefited most, however high prior knowledge learners were not disadvantaged by the misconception-based approach. The findings suggest that online multimedia can be greatly improved, promoting conceptual change in students with all levels of experience, by including a discussion of misconceptions.

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

cognitive load theory
multimedia learning
physics education research
vicarious learning


Clustering financial time series: an application to mutual funds style analysis Classification can be useful in giving a synthetic and informative description of contexts characterized by high degrees of complexity. Different approaches could be adopted to tackle the classification problem: statistical tools may contribute to increase the degree of confidence in the classification scheme. A classification algorithm for mutual funds style analysis is proposed, which combines different statistical techniques and exploits information readily available at low cost. Objective, representative, consistent and empirically testable classification schemes are strongly sought for in this field in order to give reliable information to investors and fund managers who are interested in evaluating and comparing different financial products. Institutional classification schemes, when available, do not always provide consistent and representative peer groups of funds. A return-based classification scheme is proposed, which aims at identifying mutual funds styles by analysing time series of past returns. The proposed classification procedure consists of three basic steps: (a) a dimensionality reduction step based on principal component analysis, (b) a clustering step that exploits a robust evolutionary clustering methodology, and (c) a style identification step via a constrained regression model first proposed by William Sharpe. The algorithm is tested on a sample of Italian mutual funds and achieves satisfactory results with respect to (i) the agreement with the existing institutional classification and (ii) the explanatory power of out of sample variability in the cross-section of returns.

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

classification
clustering
mutual funds style analysis


Nonspecificity in R-n Open problems posed by Klir and Wierman (1998) for a nonspecificity measure are solved; the measure is proven additive, and its extension to nonconvex sets given. Several different proofs of additivity are given, to suggest certain techniques of wider applicability in system problems and to motivate further research possibilities. A study is initiated to refine nonspecificity separately to each dimension kless than or equal ton for the bodies residing in R-n.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O 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 nonspecificity
cartesian additivity
measures of specificity
measures of uncertainty


An instance-weighting method to induce cost-sensitive trees We introduce an instance-weighting method to induce cost-sensitive trees. It is a generalization of the standard tree induction process where only the initial instance weights determine the type of tree to be induced-minimum error trees or minimum high cost error trees. We demonstrate that it can be easily adapted to an existing tree learning algorithm. Previous research provides insufficient evidence to support the idea that the greedy divide-and-conquer algorithm can effectively induce a truly cost-sensitive tree directly from the training data. We provide this empirical evidence in this paper. The algorithm incorporating the instance-weighting method is found to be better than the original algorithm in terms of total misclassification costs, the number of high cost errors, and tree size in two-class data sets. The instance-weighting method is simpler and more effective in implementation than a previous method based on altered priors.

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

cost-sensitive
decision trees
greedy divide-and-conquer algorithm
instance weighting


Correlations in spiking neuronal networks with distance dependent connections Can the topology of a recurrent spiking network be inferred from observed activity dynamics? Which statistical parameters of network connectivity can be extracted from firing rates, correlations and related measurable quantities? To approach these questions, we analyze distance dependent correlations of the activity in small-world networks of neurons with current-based synapses derived from a simple ring topology. We find that in particular the distribution of correlation coefficients of subthreshold activity can tell apart random networks from networks with distance dependent connectivity. Such distributions can be estimated by sampling from random pairs. We also demonstrate the crucial role of the weight distribution, most notably the compliance with Dales principle, for the activity dynamics in recurrent networks of different types.

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

spiking neural networks
small-world networks
pairwise correlations


Information systems implementation within US agribusiness: an applications approach The complexity and sophistication of information system depends upon the information processing needs at the firm level. Agribusinesses tend to be heterogeneous in terms of firm size, operator characteristics, and opportunities for strategic behavior. Thus, information system hardware and software sophistication is expected to differ significantly even within similar industries. This study employs survey data from US agribusiness firms in order to determine the factors that contribute to hardware and software sophistication. Sophistication levels relative to hardware and software many times are a function of firm size and sales. It is also shown that a manager needs to recognize the level of sophistication in order to gauge competitive positioning against firm rivals. To be competitive within specific agribusiness sectors a firm must maintain or acquire the requisite information technology of its rivals.

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

agribusiness information systems
software and hardware sophistication
competitive applications


A testing strategy for abstract classes One of the characteristics of the increasingly widespread use of object-oriented libraries and the resulting intensive use of inheritance is the proliferation of dependencies on abstract classes. Since abstract classes cannot be instantiated, they cannot be tested in isolation using standard execution-based testing strategies. A standard approach to testing abstract classes is to instantiate a concrete descendant class and test the features that are inherited. This paper presents a structured approach that supports the testing of features in abstract classes, paying particular attention to ensuring that the features tested are those defined in the abstract class. Two empirical studies are performed on a suite of large Java programs and the results presented. The first study analyses the role of abstract classes from a testing perspective. The second study investigates the impact of the testing strategy on the programs in this suite to demonstrate its feasibility and to comment on the pragmatics of its use. Copyright (c) 2010 John Wiley & Sons, Ltd.

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 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 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


Monte Carlo simulation of flow of fluids through porous media This simulation employs Monte Carlo technique for studying fluid flow through a porous medium in the capillary regime. The medium has been modelled as a 2 or 3-dimensional network of elements, some of which are randomly closed to the fluid flow. Dijkstra's algorithm has been employed to identify the least-resistance pathway, which is instrumental in determining the minimum pressure required to achieve break-through across the network. At higher pressures, network resistance has been calculated by determining the manner in which the cluster forms and by accounting for the nature of flowpaths. The simulation yields a linear relationship between the pressure applied across the network and flowrate showing similarity to Darcy's law. Polynominal fitting of the data on the fraction of openable pores open as dependent on pressure applied across the network has been carried out and the coefficients determined. (C) 2002 Elsevier Science Ltd. All rights reserved.

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

monte carlo
simulation
porous media
fluid flow


Augmenting organizational memory: A field study of answer garden A growing concern for organizations and groups has been to augment their knowledge and expertise. One such augmentation is to provide an organizational memory, some record of the organization's knowledge. However, relatively little is known about how computer systems might enhance organizational, group, or community memory. This article presents Answer Garden, a system for growing organizational memory. The article describes the system and its underlying implementation. It then presents findings from a field study of Answer Garden. The article discusses the usage data and qualitative evaluations from the field study, and then draws a set of lessons for next-generation organizational memory systems.

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 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 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 B I O

performance
reliability
collective memory
computer-supported cooperative work
cscw
field studies
group memory


A Study of Practical Deduplication We collected file system content data from 857 desktop computers at Microsoft over a span of 4 weeks. We analyzed the data to determine the relative efficacy of data deduplication, particularly considering whole-file versus block-level elimination of redundancy. We found that whole-file deduplication achieves about three quarters of the space savings of the most aggressive block-level deduplication for storage of live file systems, and 87% of the savings for backup images. We also studied file fragmentation, finding that it is not prevalent, and updated prior file system metadata studies, finding that the distribution of file sizes continues to skew toward very large unstructured files.

O B O O B 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 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 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

measurement performance windows filesystem


Bent and generalized bent Boolean functions In this paper, we investigate the properties of generalized bent functions defined on with values in , where q a parts per thousand yen 2 is any positive integer. We characterize the class of generalized bent functions symmetric with respect to two variables, provide analogues of Maiorana-McFarland type bent functions and Dillon's functions in the generalized set up. A class of bent functions called generalized spreads is introduced and we show that it contains all Dillon type generalized bent functions and Maiorana-McFarland type generalized bent functions. Thus, unification of two different types of generalized bent functions is achieved. The crosscorrelation spectrum of generalized Dillon type bent functions is also characterized. We further characterize generalized bent Boolean functions defined on with values in and . Moreover, we propose several constructions of such generalized bent functions for both n even and n odd.

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

generalized boolean functions
walsh-hadamard transform


A systematic evaluation of the benefits and hazards of variable selection in latent variable regression. Part II. Practical applications Leave-multiple-out cross-validation (LMO-CV) is compared to leave-one-out cross-validation (LOO-CV) as objective function in variable selection for four real data sets. Two data sets stem from NIR spectroscopy and two from quantitative structure-activity relationships. In all four cases, LMO-CV outperforms LOO-CV with respect to prediction quality, model complexity (number of latent variables) and model size (number of variables). The number of objects left out in LMO-CV has an important effect on the final results. It controls both the number of latent variables in the final model and the prediction quality. The results of variable selection need to be validated carefully with a validation step that is independent of the variable selection. This step needs to be done because the internal figures of merit (i.e. anything that is derived from the objective function value) do not correlate well with the external predictivity of the selected models. This is most obvious for LOO-CV. LOO-CV without further constraints always shows the best internal figures of merit and the worst prediction quality. Copyright (C) 2002 John Wiley Sons, Ltd.

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 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 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


Pseudo-random number generation for Brownian Dynamics and Dissipative Particle Dynamics simulations on GPU devices Brownian Dynamics (BD), also known as Langevin Dynamics, and Dissipative Particle Dynamics (DPD) are implicit solvent methods commonly used in models of soft matter and biomolecular systems. The interaction of the numerous solvent particles with larger particles is coarse-grained as a Langevin thermostat is applied to individual particles or to particle pairs. The Langevin thermostat requires a pseudo-random number generator (PRNG) to generate the stochastic force applied to each particle or pair of neighboring particles during each time step in the integration of Newtons equations of motion. In a Single-Instruction-Multiple-Thread (SIMT) GPU parallel computing environment, small batches of random numbers must be generated over thousands of threads and millions of kernel calls. In this communication we introduce a one-PRNG-per-kernel-call-per-thread scheme, in which a micro-stream of pseudorandom numbers is generated in each thread and kernel call. These high quality, statistically robust micro-streams require no global memory for state storage, are more computationally efficient than other PRNG schemes in memory-bound kernels, and uniquely enable the DPD simulation method without requiring communication between threads.

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

gpu
brownian dynamics
dissipative particle dynamics

molecular dynamics
random number generation


Symbol error rate calculation and data pre-distortion for 16-QAM transmission over nonlinear memoryless satellite channels This paper presents a simplified mathematical approach to evaluate the performance of any given circular constellation of 16-level quadrature amplitude modulation (16-QAM) in terms of symbol error rate (SER). Following this approach, with the aim to work with memoryless nonlinear satellite channels, a model is derived as a generalized form for both linear and nonlinear channels in the presence of down link additive white Gaussian noise (AWGN). The analysis provides means to calculate the optimal ring ratio (RR) and phase difference (PD) for several possible candidates of 16-QAM circular constellations. The effects of RR and PD on the SER performance are investigated in the analysis. To overcome the nonlinear distortion, data pre-distortion is taken into account in the study. The paper gives a general procedure for data pre-distortion implementation for all circular 16-QAM constellations. The analytical formulation has been extended for total degradation (TD) performance measure as a function of input back-off (IBO) of the nonlinear amplifier. A SER performance-comparison between different constellations for 16-QAM systems has also been presented in this paper. The analytical results are validated by simulation. Copyright (C) 2006 John Wiley & Sons, Ltd.

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

symbol error rate
nonlinear distortion
satellite channels


Synthesis of multiplexed biofluidic microchips Lab-on-a-chip (LoC) devices are a class of microfluidic chip-based systems that show a great deal of promise for complex chemical and biological sensing and analysis applications. An approach for full-custom LoC design, which leverages optimal design techniques and system-on-a-chip (SoC) physical design methods, is being developed. Both physical design of the chip and microfluidic performance are simultaneously considered to obtain complete LoC layouts. The proposed approach is demonstrated by designing multiplexed capillary electrophoresis (CE) separation microchips. The authors believe that this approach provides a foundation for future extension to LoC devices in which many different complex chemical operations are performed entirely on-chip.

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

biochips
lab-on-a-chip design
microfluidic layout


A multi-start iterated local search with tabu list and path relinking for the two-echelon location-routing problem The two-echelon location-routing problem (LRP-2E) is raised by the design of transportation networks with two types of trips: first-level trips serving from one main depot a set of satellite depots, to be located, and second-level trips supplying customers from these satellites. In the proposed multi-start iterated local search (MS-ILS), three greedy randomized heuristics are used cyclically to get initial solutions. Each ILS run alternates between two search spaces: LRP-2E solutions, and travelling salesman (TSP) tours covering the main depot and the customers. The number of iterations allotted to a run is reduced whenever a known solution (stored in a tabu list) is revisited. MS-ILS can be reinforced by a path-relinking procedure (PR), used internally for intensification, as post-optimization, or both. On two sets with 24 and 30 LRP-2E instances, MS-ILS outperforms on average two GRASP algorithms and adding PR brings a further improvement. Our metaheuristic also surpasses a tabu search on 30 instances for a more general problem with several main depots. It is still effective on a particular case, the capacitated location-routing problem (CLRP): In a comparison with four published metaheuristics, only one (LRGTS, Prins et al., 2007) does better.

O O B I 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 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

vehicle routing
facility location
two-echelon location-routing problem


An overview of rough set semantics for modal and quantifier logics In this paper, we would like to present some logics with semantics based on rough set theory and related notions. These logics are mainly divided into two classes. One is the class of modal logics and the other is that of quantifier logics. For the former, the approximation space is based on a set of possible worlds, whereas in the latter, we consider the set of variable assignments as the universe of approximation. In addition to surveying some well-known results about the links between logics and rough set notions, we also develop some new applied logics inspired by rough set theory.

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

modal logic
epistemic logic
rough quantifiers


On improved confidence bounds for system reliability In this paper, new bounding strategies are presented to improve confidence interval estimation for system reliability based on component level reliability, and associated uncertainty data. Research efforts have been focused on two interdependent areas: 1) development & improvement of analytical approaches for quantifying the uncertainty associated with the system reliability estimate when data regarding component reliability is available; and 2) based on these analytical approaches, generating statistical inference methods that can be used to make accurate estimations about the reliability of a system. The analytical approach presented relies on a recursive rationale that can be applied to obtain the variance associated with the system reliability estimate, provided the system can be decomposed into a series-parallel configuration. The bounding procedure is independent of parametric assumptions regarding component time to failure, and can be applied whenever component reliability data are available. To assess the validity of the proposed procedure, three test cases have been analyzed. For each case, Monte-Carlo simulation has been used to generate component failure data, based on nominal component reliability values. Based on these simulated data, lower bounds have been constructed, and then compared against nominal system reliability to generate an expected confidence level. The results obtained exhibit a significant improvement in the accuracy of the confidence intervals for the system reliability when compared with existing approximation methods. The procedure described is effective, relatively simple, and widely applicable.

O O O O O O 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 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 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

reliability estimation
series-parallel systems


Performance evaluation of STRON: A hardware implementation of a real-time OS In a real-time system, it is required to reduce the response time to an interrupt signal, as well as the execution time of a Real-Time Operating System (RTOS). In order to satisfy this requirement, we have proposed a method of implementing some of the functionalities of an RTOS using hardware. Based on this idea, we have implemented a VLSI chip, called STRON (silicon TRON: The Realtime Operating system Nucleus), to enhance the performance of an RTOS, where the STRON chip works as a peripheral unit of any MPU. In this pa per we describe the hardware architecture of the STRON chip and the performance evaluation results of the RTOS using the STRON chip. The following results were obtained. (1) The STRON chip is implemented in only about 10,000 gates when the number of each object (task, event flag, semaphore, and interrupt) is 7. (2) The task scheduler can execute within 8 clocks in a fixed period using the hardware algorithm when the number of tasks is 7. (3) Most of the basic mu ITRON system calls using the STRON chip can be executed in a fixed period of a few microseconds. (4) The execution time of a system call, measured by a multitask application program model, can be reduced to about one-fifth that in the case of the conventional software RTOS. (5) The total performance, including context switching, is about 2.2 times faster than that of the software RTOS. We conclude that the execution time of the part of the system call implemented by the STRON chip can almost be ignored, but the part of the interface software and context switching related to the architecture of a MPU strongly influence the total performance of an RTOS.

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

real-time system
real-time os
hardware os
silicon tron (stron)
silicon os (sos)


scheduling strategies for optimistic parallel execution of irregular programs Recent application studies have shown that many irregular applications have a generalized data parallelism that manifests itself as iterative computations over worklists of different kinds. In general, there are complex dependencies between iterations. These dependencies cannot be elucidated statically because they depend on the inputs to the program; thus, optimistic parallel execution is the only tractable approach to parallelizing these applications. We have built a system called Galois that supports this style of parallel execution. Its main features are (i) set iterators for expressing worklist-based data parallelism, and (ii) a runtime system that performs optimistic parallelization of these iterators, detecting conflicts and rolling back computations as needed. Our work builds on the Galois system, and it addresses the problem of scheduling iterations of set iterators on multiple cores. The policy used by the base Galois system is to assign an iteration to a core whenever it needs work to do, but we show in this paper that this policy is not optimal for many applications. We also argue that OpenMP-style DO-ALL loop scheduling directives such as chunked and guided self-scheduling are too simplistic for irregular programs. These difficulties led us to develop a general scheduling framework for irregular problems; OpenMP-style scheduling strategies are special cases of this general approach. We also provide hooks into our framework, allowing the programmer to leverage application knowledge to further tune a schedule for a particular application. To evaluate this framework, we implemented it as an extension of the Galois system. We then tested the system using five real-world, irregular, data-parallel applications. Our results show that (i) the optimal scheduling policy can be different for different applications and often leverages application-specific knowledge and (ii) implementing these schedules in the Galois system is relatively straightforward.

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

runtime system
framework
applications
policy
general
knowledge
paper
program
dependencies
strategies
irregular programs
parallel
data parallelism
core
scheduling
programmer

conflict
direct
extensibility
evaluation
systems
openmp
optimality
optimistic parallelism
complexity
feature
iter


New Formulation for the Recursive Transfer Method Using the Weak Form Theory Framework and Its Application to Microwave Scattering The recursive transfer method (RTM) is a numerical technique that was developed to analyze scattering phenomena and its formulation is constructed with a difference equation derived from a differential equation by Numerov's discretization method. However,. the differential equation to which Numerov's method is applicable is restricted and therefore the application range of RTM is also limited. In this paper, we provide a new discretization scheme to extend RTM formulation using the weak form theory framework. The effectiveness of the proposed formulation is confirmed by microwave scattering induced by a metallic pillar placed asymmetrically in the waveguide. A notable feature of RTM is that it can extract a localized wave from scattering waves even if the tail of the localized wave reaches to the ends of analyzing region. The discrepancy between the experimental and theoretical data is suppressed with in an upper bound determined by the standing wave ratio of the waveguide.

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

recursive transfer method
weak form theory
microwave scattering
localized wave