Governance of open content creation: A conceptualization and analysis of control and guiding mechanisms in the open content domain The open content creation process has proven itself to be a powerful and influential way of developing text-based content, as demonstrated by the success of Wikipedia and related sites. Distributed individuals independently edit, revise, or refine content, thereby creating knowledge artifacts of considerable breadth and quality. Our study explores the mechanisms that control and guide the content creation process and develops an understanding of open content governance. The repertory grid method is employed to systematically capture the experiences of individuals involved in the open content creation process and to determine the relative importance of the diverse control and guiding mechanisms. Our findings illustrate the important control and guiding mechanisms and highlight the multifaceted nature of open content governance. A range of governance mechanisms is discussed with regard to the varied levels of formality, the different loci of authority, and the diverse interaction environments involved. Limitations and opportunities for future research are provided.

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

user generated content
collaboration
editing


Temporal interdependence in fuzzy MCDM problems Contemporaneous MCDM methodology is based on the simplifying assumption of independent objectives. This restriction was partly relaxed through the concept of(static) interdependent objectives introduced by C. Carlsson and R. Fuller. Most real world managerial decision problems involve interdependent objectives, yet in a temporal setting. In the paper we generalize the static concept to temporal fuzzy multiobjective programming problem. We introduce the concepts temporal support and temporal conflict in the objective set within both infinite and finite planning horizons. We also formulate dynamic versions of membership functions for interdependent objectives in crisp and fuzzy multiobjective programming problems. The new concepts are used to describe and model temporal goal conflicts in numerical illustrations. (C) 1997 Elsevier Science B.V.

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

temporal interdependence
fuzzy multiobjective programming


Real-time view-based pose recognition and interpolation for tracking initialization In this paper we propose a new approach to real-time view-based pose recognition and interpolation. Pose recognition is particularly useful for identifying camera views in databases, video sequences, video streams, and live recordings. All of these applications require a fast pose recognition process, in many cases video real-time. It should further be possible to extend the database with new material, i.e., to update the recognition system online. The method that we propose is based on P-channels, a special kind of information representation which combines advantages of histograms and local linear models. Our approach is motivated by its similarity to information representation in biological systems but its main advantage is its robustness against common distortions such as clutter and occlusion. The recognition algorithm consists of three steps: (1) low-level image features for color and local orientation are extracted in each point of the image; (2) these features are encoded into P-channels by combining similar features within local image regions; (3) the query P-channels are compared to a set of prototype P-channels in a database using a least-squares approach. The algorithm is applied in two scene registration experiments with fisheye camera data, one for pose interpolation from synthetic images and one for finding the nearest view in a set of real images. The method compares favorable to SIFT-based methods, in particular concerning interpolation. The method can be used for initializing pose-tracking systems, either when starting the tracking or when the tracking has failed and the system needs to re-initialize. Due to its real-time performance, the method can also be embedded directly into the tracking system, allowing a sensor fusion unit choosing dynamically between the frame-by-frame tracking and the pose recognition.

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

p-channels
real-time processing
view-based computer vision


Investigation on Key Technologies in Large-Scale MIMO Large-scale MIMO (multiple-input multiple-output) systems with numerous low-power antennas can provide better performance in terms of spectrum efficiency, power saving and link reliability than conventional MIMO. For large-scale MIMO, there are several technical issues that need to be practically addressed (e.g., pilot pattern design and low-power transmission design) and theoretically addressed (e.g., capacity bound, channel estimation, and power allocation strategies). In this paper, we analyze the sum rate upper bound of large-scale MIMO, investigate its key technologies including channel estimation, downlink precoding, and uplink detection. We also present some perspectives concerning new channel modeling approaches, advanced user scheduling algorithms, etc.

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

channel estimation
downlink precoding
uplink detection


An adaptive bluetooth packet selection and scheduling scheme in interference environments Bluetooth is a new technology for Wireless Personal Area Networks (WPANs). It intends to eliminate the need of wires and connectors between a variety of devices, like PCs and their peripherals, walkmans and their earphones, etc. Bluetooth provides robust and secure wireless radio communication of both data and voice, even when the devices are not within line-of-sight. Bluetooth employs the 2.4 GHz ISM band, sharing the same band with the Wireless LAN (WLAN) implementing the IEEE 802.11 series standard. While WLANs and WPANs are complementary rather than competing technologies, the likelihood of mutual interference may occur unexpectedly, which may impact the performance of either severely. In this paper, we propose a Bluetooth channel state dependent data segmentation and reassembly (CSD-SAR) scheme and a queue state dependent priority (QSD-PR) scheduling policy. The CSD-SAR maintains a receiving frequency table to predict channel conditions and selects the best packet type and packet size to transmit data. In this way, it not only masks bad frequencies without delaying transmission but also leads to the best performance with high link utilization in error-prone environments. In addition, the QSD-PR also uses the receiving frequency table to avoid bad frequencies and gives a selected master-slave pair, which has more queued data to send between each other, a higher priority to eliminate the wastage of slots. The conventional scheduling policy, Round Robin (RR), yields poor performance with the time division duplex based MAC protocol and results in slot wastage and may not ensure fairness. Simulation results show that our proposed scheme achieves better link utilization and higher throughput with bounded delay compared to the RR scheme in error-free and error-prone environments. Our scheme can also eliminate interference to other wireless networks that share the same spectrum, such as WLANs, by avoiding selecting channels occupied by other networks. (c) 2006 Elsevier B.V. All rights reserved.

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

channel state dependent packet scheduling


Reliability in Source Coding With Side Information We study error exponents for source coding with side information. Both achievable exponents and converse bounds are obtained for the following two cases: lossless source coding with coded information and lossy source coding with full side information (Wyner-Ziv). These results recover and extend several existing results on source-coding error exponents and are tight in some circumstances. Our bounds have a natural interpretation as a two-player game between nature and the code designer, with nature seeking to minimize the exponent and the code designer seeking to maximize it. In the Wyner-Ziv problem, our analysis exposes a tension in the choice of test channel with the optimal test channel balancing two competing error events. The Gaussian and binary-erasure cases are examined in detail.

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

error exponents
side information
source coding

test channel optimization
wyner-ziv problem


Topological analysis of tetraphosphorus oxides (P4O6+n (n=0-4)) Quantum chemical calculations were used to analyze the chemical bonding and the reactivity of phosphorus oxides (P4O6+n (n = 0-4)). The chemical bonding was studied using topological analysis such as atoms in molecules (AIM), electron localization function (ELF), and the reactivity using the Fukui function. A classification of the P-O bonds formed in all structures was done according to the coordination number in each P and O atoms. It was found that there are five P-O bond types and these are distributed among the five phosphorus oxides structures. Results showed that there is good agreement among the evaluated properties (length, bond order, density at the critical point, and disynaptic population) and each P-O bond type. It was found that regardless of the structure in which a P-O bond type is present the topological and geometric properties do not have a significant variation. The topological parameters electron density and Laplacian of electron density show excellent linear correlation with the average length of P-O bond in each bond type for each structure. From the Fukui function analysis it was possible to predict that from P4O6 until P4O8 the most reactive regions are basins over the P.

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

atoms in molecules
the fukui function
topological analysis


An efficient algorithm for computing permanental polynomials of graphs An efficient numerical method for computing permanental polynomials of graphs is proposed. It adapts multi-entry expansion of FFT, and is parallel in nature. It is applied to fullerene-type graphs, and works for C-56, while the largest fullerene computed before is C-40. Extensive numerical computations show that the algorithm is fast and stable. (C) 2006 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 B O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O

permanental polynomial
adjacency matrix
graph


Certificateless undeniable signatures from bilinear maps Certificateless public-key cryptosystem avoids the inherent key escrow problem in identity-based public-key cryptosystem, and does not need expensive certificates in the public key infrastructure. This cryptographic primitive has received a significant attention since it was introduced, and lots of certificateless schemes have been proposed in the past years. In this paper, we propose an certificateless undeniable signature scheme based on bilinear maps. To formally analyze the security of the proposed scheme, we extend security notions of undeniable signatures in the traditional public key infrastructure to the certificateless setting. Under the formally defined security models, we prove that our proposed scheme satisfies all the security properties under certain standard assumptions in the random oracle model. Compared with existed certificateless undeniable signatures, the sign algorithm of our scheme is more efficient, the weakness is that the unforgeability of our scheme is proved in a weak model.

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

undeniable signature
random oracle model
bilinear maps

certificateless public-key cryptography
provable security


A genetic algorithm approach for the cutting stock problem In this paper, a genetic algorithm approach is developed for solving the rectangular cutting stock problem, The performance measure is the minimization of the waste. Simulation results obtained from the genetic algorithm-based approach are compared with one heuristic based on partial enumeration of all feasible patterns, and another heuristic based on a genetic neuro-nesting approach. Some test problems taken from the literature were used for the experimentation. Finally, the genetic algorithm approach was applied to test problems generated randomly. The simulation results of the proposed approach in terms of solution quality are encouraging when compared to the partial enumeration-based heuristic and the genetic neuro-nesting approach.

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


content-based video genre classification using multiple cues This paper presents an automatic video genre classification system, which utilizes several low-level audio-visual cues as well as cognitive and structural information to classify the types of TV programs and YouTube videos. Classification is performed using support vector machines. The system is integrated to our content-based video processing system and shares the same features that we have been using for high-level feature detection task in TRECVID evaluations. The proposed system is extensively evaluated using complete TV programs from Italian RAI TV channel, from French TV channels, and videos from YouTube on which 99.6\%, 99\%, and 92.4\% correct classification rates are attained, respectively. These results show that the developed system can reliably determine TV programs' genre. It also provides a good basis for classifying genres of YouTube videos, which can be improved by using additional information, such as tags and titles, to obtain more robust results. Further experiments indicate that the quality of video does not influence the results significantly. It is found that the performance drop in classifying genres of YouTube videos is mainly due to the large variety of content contained in these videos.

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

youtube videos
genre classification
tv programs


Statistical and information-theoretic analysis of resolution in imaging In this paper, some detection-theoretic, estimation-theoretic, and information-theoretic methods are investigated to analyze the problem of determining resolution limits in imaging systems. The canonical problem of interest is formulated based on a model of the blurred image of two closely spaced point sources of unknown brightness. To quantify a measure of resolution in statistical terms, the following question is addressed: "What is the minimum detectable separation between two point sources at a given signal-to-noise ratio (SNR), and for prespecified probabilities of detection and false alarm (P-d and P-f)?". Furthermore, asymptotic performance analysis for the estimation of the unknown parameters is carried out using the Cramer-Rao bound. Although similar approaches to this problem (for one-dimensional (I-D) and oversampled signals) have been presented in the past, the analyzes presented in this paper are carried out for the general two-dimensional (2-D) model and general sampling scheme. In particular the case of under-Nyquist (aliased) images is studied. Furthermore, the Kullback-Liebler distance is derived to further confirm the earlier results and to establish a link between the detection-theoretic approach and Fisher information. To study the effects of variation in point spread function (PSF) and model mismatch, a perturbation analysis of the detection problem is presented as well.

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

detection
estimation
fisher information
imaging
model mismatch
perturbation analysis
resolution

aliasing
cramer-rao bound
information-theoretic imaging
kullback-liebler distance
variational analysis


Schema coordination in federated database management: a comparison with schema integration We have introduced a new approach, termed schema coordination, as an alternative to the well-known schema integration approach for processing cooperative queries in federated database systems. The schema coordination approach is based on the attribute correspondence matrix that links similar attributes in all component databases. In this paper, we compare the schema coordination approach with the schema integration approach for both metadata management and cooperative query processing. We demonstrate that schema coordination offers a much simpler methodology that enables logical data independence and is especially better suited for database federations consisting of many competing databases with ever-evolving metadata. (C) 1997 Elsevier Science B.V.

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

federated database systems
metadata management
schema coordination
schema integration


experimental study of cockpit displays of traffic information for pilot self-spacing in congested airspace An experimental study examined cockpit displays of traffic information for pilot self-spacing in congested airspace. Results demonstrate that pilots have the capability to benefit from additional traffic information and take over some additional control responsibility. Additionally, this experiment shows that pilots benefit from the presentation of velocity and closure rate, and from range spacing arcs.

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

air traffic control
cockpit display of traffic information


Measuring the level of difficulty in single player video games In this paper, we discuss the interest and the need to evaluate the difficulty of single player video games. We first show the importance of difficulty, drawing from semiotics to explain the link between tension-resolution cycles and challenge with the players enjoyment. Then, we report related work on automatic gameplay analysis. We show through a simple experimentation that automatic video game analysis is both practicable and can lead to interesting results. We argue that automatic analysis tools are limited if they do not consider difficulty from the player point of view. The last two sections provide a player and Game Design oriented definition of the challenge and difficulty notions in games. As a consequence we derive the property that must fulfil a measurable definition of difficulty.

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


Clinical Use of Relaxin to Facilitate Birth: Reasons for Investigating the Premise Abstract: In the United States, both medical and nonmedical factors have driven the cesarean section rate to over 26% of all deliveries. In addition to questions of increased cost associated with operative delivery, some have questioned the ethics of performing cesarean section for nonmedical reasons. Reduction of both the duration and the pain associated with vaginal delivery would likely bring about a decline in the rate of both medical and nonmedical cesarean sections. This chapter summarizes recent findings that support the premise that through its growth-promoting and softening effects on the cervix, short-term subcutaneous administration of pharmacologic amounts of relaxin to women at term holds promise as a means of reducing the duration and discomfort associated with delivery. Two recent studies conducted in pregnant rats demonstrated that the cervix is highly responsive to relaxin during the antepartum period and that short-term subcutaneous administration of the hormone to relaxin-deficient animals not only promotes growth and softening of the cervix, but also reduces the duration of labor and delivery. Moreover, recent human clinical trials examining the influence of 24 weeks of continuous subcutaneous administration of recombinant human relaxin for the treatment of scleroderma provided evidence not only that the human reproductive tract is responsive to relaxin, but also that the administration of the hormone does not cause serious adverse side effects. It is concluded that recent findings provide an impetus for an investigation into relaxin's potential for cervical remodeling and facilitating birth in women.

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


improving social game engagement on facebook through enhanced socio-contextual information In this paper we describe the results of a controlled study of a social game, Magpies , which was built on the Facebook Online Social Network (OSN) and enhanced with contextual social information in the form of a variety of social network indices. Through comparison with a concurrent control trial using an identical game without the enhanced social information, it was shown that the additional contextual data increased the frequency of social activity between players engaged in the game. Despite this increase in activity, there was little increase in growth of the player-base when compared to the control condition. These findings corroborate previous work that showed how socio-contextual enhancement can increase performance on task-driven games, whilst also suggesting that it can increase activity and engagement when provided as context for non task-driven game environments.

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

mediated interaction
social visualisations
social network analysis
social context
social gaming


Decomposition of two-dimensional shapes for efficient retrieval This paper presents a novel approach to address the problem of generic 2D shape recognition. We propose a morphological method to decompose a binary shape into entities in correspondence with their protrusions. Each entity is associated with a set of perceptual features that can be used in indexing into image databases. The matching process, based on the softassign algorithm, has produced encouraging results, showing the potential of the developed method in a variety of computer vision and pattern recognition domains. The results demonstrate its robustness in the presence of scale, reflection and rotation transformations and prove the ability to handle noise and articulated structures. In order to increase efficiency, the retrieval process is applied after a coarse scale grouping of objects, without sacrificing effectiveness and allowing indexing into large shape databases.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O 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 decomposition
morphological skeleton
shape representation
shape retrieval
shape matching
object recognition


Accessibility of U.S. federal government home pages: Section508 compliance and site accessibility statements U.S. federal websites are required to be accessible for people with impairments. However, despite the existing regulations and guidelines, many federal websites continue to be inaccessible, and accessibility policy statements available on federal websites often do not provide any useful information. This paper provides three contributions to the research literature: (1) an accessibility evaluation of 100 federal home pages using both human and automated methods, (2) a content analysis of existing website accessibility policy statements, and (3) a discussion of the relationship between actual Section 508 compliance and the existing accessibility policy statements on a website. The paper concludes with recommendations for improving policy related to Section508 compliance for websites.

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

accessibility policy compliance section508

disability
impairment
open government
assistive technology
universal usability


Impact of productivity on cross-training configurations and optimal staffing decisions in hospitals Optimal cross-training decision under stochastic demand and productivity changes. Centralized and decentralized decision making analyzed for three configurations. Beyond threshold productivity fewer nurses provide benefit. Chaining policy on average provides 1.20% cost savings over partial flexibility. Productivity moderates demand increase and optimal cross-training decisions.

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

cross-training
healthcare
stochastic programming


Simulation of infinitely strongly interacting fermions from one to two dimensions The limit of infinitely strong interaction is the relevant one for understanding the low energy sector of strongly correlated electronic systems like high-temperature superconductors and new related compounds like the so-called ladder materials. The t-J model is the generic one, where strong correlation is taken into account by projecting out doubly occupied sites. We present simulations for both the single-hole and finite doping cases of the t-J model performed with newly developed quantum Monte Carlo algorithms, in chains, ladders, and planes, where the spectral function and the quasiparticle weight are obtained. (C) 2002 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

strongly correlated fermions
loop algorithms
determinantal algorithm


Locally Enhancing Fractal Descriptors by Using the Non-additive Entropy A new method is proposed to extract features from texture images. The method computes the local non-additive entropy of fractal descriptors. It outperformed other state-of-the-art approaches in texture classification. The method also achieved great results in the automatic taxonomy of plants. This new type of analysis is potentially useful for general purpose applications.

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

non-additive entropy
texture analysis
pattern recognition


A deterministic inventory/production model with general inventory cost rate function and piecewise linear concave production costs We present a thorough analysis of the economic production quantity model with shortages under a general inventory cost rate function and piecewise linear concave production costs. Consequently, an effective solution procedure, particularly useful for an approximation scheme, is proposed. A computational study is appended to illustrate the performance of the proposed solution procedure.

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


On the effect of user mobility and density on the performance of protocols for ad-hoc mobile networks In this paper, we demonstrate the significant impact of (a) the mobility rate and (b) the user density on the performance of routing protocols in ad-hoc mobile networks. In particular, we study the effect of these parameters on two different approaches for designing routing protocols: (a) the route creation and maintenance approach and (b) the 'support' approach that forces few hosts to move, acting as 'helpers' for message delivery. We study one representative protocol for each approach, i.e. AODV for the first approach and RUNNERS for the second. We have implemented the two protocols and performed a large scale and detailed simulation study of their performance. The main findings are: the AODV protocol behaves well in networks of high user density and low mobility rate, while its performance drops for sparse networks of highly mobile users. On the other hand, the RUNNERS protocol seems to tolerate well (and in fact benefit from) high mobility rates and low densities. Copyright (C) 2004 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 O O B I O O O O B I O O O O O O O O O O O O O O O O O O O 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 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

routing protocols
user mobility
user density

ad-hoc mobile networks
performance evaluation
experiments


Plan recognition for interface agents Interface agents are computer programs that provide personalized assistance to a user dealing with computer based applications. By understanding the tasks the user performs in a software application an interface agent could be aware of the context that represents the user's focus of attention at each particular moment. With this purpose, plan recognition aims at identifying the plans or goals of a user from the tasks he (for simplicity, we use "he" to refer to the user, but we do not mean any distinctions about sexes) performs. A prerequisite for the recognition of plans is knowledge of a user's possible tasks and the combination of these tasks in complex task sequences, which describes typical user behavior. Plan recognition will enable an interface agent to reason about what the user might do next so that it can determine how to assist him. In this work we present the state of the art in Plan Recognition, paying special attention to the features that make it useful to interface agents. These features include the ability to deal with uncertainty, multiple plans, multiple interleaved goals, overloaded tasks, noisy tasks, interruptions and the capability to adapt to a particular user.

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


Cahn-Hilliard modeling of particles suspended in two-phase flows In this paper, we present a model for the dynamics of particles suspended in two-phase flows by coupling the CahnHilliard theory with the extended finite element method (XFEM). In the CahnHilliard model the interface is considered to have a small but finite thickness, which circumvents explicit tracking of the interface. For the direct numerical simulation of particle-suspended flows, we incorporate an XFEM, in which the particle domain is decoupled from the fluid domain. To cope with the movement of the particles, a temporary ALE scheme is used for the mapping of field variables at the previous time levels onto the computational mesh at the current time level. By combining the CahnHilliard model with the XFEM, the particle motion at an interface can be simulated on a fixed Eulerian mesh without any need of re-meshing. The model is general, but to demonstrate and validate the technique, here the dynamics of a single particle at a fluidfluid interface is studied. First, we apply a small disturbance on a particle resting at an interface between two fluids, and investigate the particle movement towards its equilibrium position. In particular, we are interested in the effect of interfacial thickness, surface tension, particle size and viscosity ratio of two fluids on the particle movement towards its equilibrium position. Finally, we show the movement of a particle passing through multiple layers of fluids. Copyright (C) 2011 John Wiley & Sons, Ltd.

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

cahn-hilliard theory
diffuse-interface model
extended finite element method (xfem)
hydrodynamics
incompressible flow
laminar flow
two-phase flows


Adjacency stable connected operators and set levelings This paper studies morphological connected operators. Particularly, it focuses on an adjacency constraint, as well as on the so-called set levelings. Some important findings are reported in this work. First, the relationships between the so-called adjacency stable operators and set levelings are investigated, and an equivalence is established. This permits to apply some properties to the related operator class. Second, the implications and limits of a property presented elsewhere that states that certain connected operators can be expressed as a sequential composition of an opening and a closing (and vice-versa) based on markers are treated. Then, a commutative property that involves alternated attribute filters is presented. In addition, other related expressions are discussed.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O 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 processing
image analysis
mathematical morphology
connected operator
adjacency stable operator
leveling
marker-based operator


Routing in optical multistage networks with limited crosstalk using ant colony optimization Ant Colony Optimization (ACO) techniques can be successfully implemented to solve many combinatorial optimization problems. After the traveling salesman problem was successfully solved using the ACO technique, other researchers have concentrated on solving other problems like the quadratic assignment and the job-shop scheduling problems using the same technique. In this paper we use the ACO technique to route messages through an N x N Optical Multistage Interconnection Network (OMIN) allowing upto 'C' limited crosstalk's (conflicts between messages within a switch) where 'C' is a technology driven parameter and is always less than 1og(2)N. Messages with switch conflicts satisfying the crosstalk constraint are allowed to pass in the same group, but if there is any link conflict, then messages have to be routed in a different group. The focus is to minimize the number of passes required for routing allowing upto 'C' limited crosstalks in an N x N optical network. This routing problem is an NP-hard problem. In this paper we show how the ACO technique can be applied to the routing problem and compare the performance of the ACO technique to that of the degree-descending algorithm using simulation techniques. Finally the lower bound estimate on the minimum number of passes required is calculated and compared to the results obtained using the two algorithms discussed. The results obtained show that the ACO technique performs better than the degree-descending algorithm and is quite close to optimal algorithms to the problem.

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

ant colony optimization
lower bound estimate
omin
routing

degree-descending algorithm
optical networks


A speaker adaptation method for non-native speech using learners native utterances for computer-assisted language learning systems In recent years, various CALL systems which can evaluate a learners pronunciation using speech recognition technology have been proposed. In order to evaluate a learners utterances and point out problems with higher accuracy, speaker adaptation is a promising technology. However, many learners who use the CALL system often have very poor speaking ability in the target language (L2), so conventional speaker adaptation methods have problems because they require the learners correctly-pronounced L2 utterances for adaptation. In this paper, we propose two new types of speaker adaptation methods for the CALL system. The new methods only require the learners utterances in their native language (L1) for adapting the acoustic model for L2. The first method is an algorithm to adapt acoustic models using a bilingual speakers utterances. The speaker-independent acoustic models of L1 and L2 are adapted to the bilingual speaker once, then they are adapted to the learner again using the learners L1 utterances. Using this method, we obtained about 5-point higher phoneme recognition accuracy than the baseline method. The second method is a training algorithm of a set of acoustic models based on speaker adaptive training. It can robustly train bilinguals models using a few utterances in L1 and L2 uttered by bilingual speakers. Using this method, we obtained about 10-point higher phoneme recognition accuracy than the baseline method.

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

non-native speech
computer-assisted language learning


An optimal algorithm for reporting visible rectangles We consider the following problem as defined by Grove et al. [Internat. J. Comput. Geom. Appl. 9 (1999) 207-217]: Given a set of n isothetic rectangles in 3D space determine the subset of rectangles, that are not completely hidden. We present an optimal algorithm for this problem that runs in O(n log n) time and O(n) space. Our result is an improvement over the one of Grove et al. by a logarithmic factor in storage and is achieved by using a different approach. An analogous approach gives non-trivial solutions for other kinds of objects too. (C) 2002 Elsevier Science B.V. All rights reserved.

computational geometry
computer graphics
object complexity
hidden surface removal
segment tree


Propofol Specifically Inhibits Mitochondrial Membrane Potential but Not Complex I NADH Dehydrogenase Activity, Thus Reducing Cellular ATP Biosynthesis and Migration of Macrophages Abstract: Propofol is a widely used intravenous anesthetic agent. Our previous study showed that a therapeutic concentration of propofol can modulate macrophage functions. Mitochondria play critical roles in the maintenance of macrophage activities. This study attempted to evaluate further the effects of mitochondria on the propofol-induced suppression of macrophage functions using mouse macrophage-like Raw 264.7 cells as the experimental model. Macrophages were exposed to a clinically relevant concentration of propofol for 1, 6, and 24 h. Analysis by the Trypan blue exclusion method revealed that propofol was not cytotoxic to macrophages. Exposure of macrophages to propofol did not affect mitochondrial NADH dehydrogenase activity of complex I. However, analysis of flow cytometry showed that propofol significantly decreased the mitochondrial membrane potential of macrophages. Cellular levels of ATP in macrophages were significantly reduced after propofol administration. In parallel with the dysfunction of mitochondria, the chemotactic analysis showed that exposure to propofol significantly inhibited the migration of macrophages. This study shows that a therapeutic concentration of propofol can specifically reduce the mitochondrial membrane potential, but there is no such effect on complex I NADH dehydrogenase activity. Modulation of the mitochondrial membrane potential may decrease the biosynthesis of cellular ATP and thus reduce the chemotactic activity of macrophages. This study provides in vitro data to validate mitochondrial dysfunction as a possible critical cause for propofol-induced immunosuppression of macrophage functions.

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

propofol
macrophages
mitochondrial membrane potential
atp


Lightweight, self-tuning data dissemination for dense nanonetworks A nanonetwork comprises a high number of autonomous nodes with wireless connectivity, assembled at micro-to-nanoscale. In general, manufacturing and cost considerations imply that nanonetworking approaches should have minimal complexity, ideally without sacrifices in network coverage. The present paper studies a networking approach fit for static, dense topologies comprising numerous, identical, computationally-constrained nodes. These attributes are especially important in the context of recently proposed applications of nanonetworks. The presented networking approach assumes that each node is equipped with 10 bits of reclaimable storage to accommodate four integer counters, and a trivial set of integer operations on them. These modest resources are used for logging packet reception statistics. Nanonodes with good reception serve as retransmitters within the network. This classification process is based on the MisraGries algorithm, used for detecting frequent items into sequential streams. Evaluation via extensive simulations in various 2D and 3D topologies yields high network coverage, achieved with less resources than related approaches.

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

wireless networks
nanoscale
low complexity


FINDING AN ASYMPTOTICALLY BAD FAMILY OF q-TH POWER RESIDUE CODES In coding theory, we are often interested in finding codes with a "good" relative minimum distance. To create a code that transmits information efficiently, we would like to see the ratio of bits containing information to total codeword length be large. In particular, for families of codes this means that as the codeword length increases, we do not significantly decrease the amount of information transmitted; for each fixed prime q we can construct a family of q-ary codes with lengths p and minimal distances d(p) with the property that as the length of these codes approaches infinity, the ration of their minimal distance to their total length tends towards epsilon > 0. In this paper, we examine families of generalized binary quadratic residue codes, named q-th power residue codes, where q is a fixed odd prime, and find an asymptotically bad subfamily of these codes. For each prime l we will construct a q-th power residue code of length p (determined by our choice of l) and minimal distance d(p), with the property that as l approaches infinity, p also tends towards infinity, and lim(l ->infinity) d(p)/p = 0.

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 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


From Lisp S-Expressions to Java Source Code The syntax of Lisp languages is based on S-expressions, an extremely simple form of structured data representation that is nevertheless fundamental to the development of Lisp syntactic extensions. By adopting a more conventional syntax, the Java language placed itself in a difficult position in regard to user-defined syntax extensions. In spite of the many efforts to provide mechanisms for such extensions, they continue to be more difficult to use than S-expression-based ones. In this paper, we will describe the use of the S-expression syntax in a Java code generation environment. By providing an S-expression based program representation for Java source code, we are able to reuse and extend Lisp macro-expansion techniques to significantly simplify the construction of Java programs.

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


Analysis and prediction of shock-induced near-field acoustics from an exhaust pipe In this study an acoustic problem of a single shock wave moving through a circular pipe instead of a real pulsating flow with blast waves is considered. Due to the failure of a linear acoustic theory for the problem of interest, the method of computational fluid dynamics is employed to analyze the present problem. For this purpose, the axisymmetric Euler equations are solved by a high-resolution method which consists of a fifth-order weighted essential non-oscillation scheme for spatial discretization and a fourth-order Runge-Kutta method for time integration. In order to reduce the large computational time on a single computer, parallel computation with seven personal computers has been conducted. The detailed flow and sound pressure fields inside and downstream of the pipe are studied. The near-field sound pressure level downstream of the pipe was computed. The sound lobe and its orientation are investigated. In particular, an interesting phenomenon of spatial variation of velocity components associated with the sound lobe is reported. It is found that the spatial variations of the streamwise velocity component and pressure are in phase. However, the spatial variations of the radial velocity component and pressure are out of phase. Moreover, the generation mechanism of acoustics is attributed to the fact of the back-and-forth reflections of upstream-moving expansion waves generated at the pipe wall corner when the shock wave diffracts around the corner. The back-and-forth wave reflections result in the formation of interlacing high- and low-pressure regions that change with time. (C) 2011 Elsevier Ltd. All rights reserved.

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 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 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 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

exhaust pipe
sound pressure level
sound lobe
euler equations


A practical error estimator in elastoplastic problems with large strains. Part II: analysis of numerical results In this second part of the paper, some properties of the discretization error estimators are presented, although their theoretical background was already developed in the first part Two numerical examples have been selected and wig be used to check some properties of these error estimators. In addition to this, some practical conclusions will be addressed from the results and graphical output of the implemented procedure.

O O O 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


Quality matching and local improvement for multilevel graph-partitioning ? Multilevel strategies have proven to be very powerful approaches in order to partition graphs efficiently. Their efficiency is dominated by two parts; the coarsening and the local improvement strategies. Several methods have been developed to solve these problems, but their efficiency has only been proven on an experimental basis. In this paper, we present new and efficient methods for both problems, while satisfying certain quality measurements. For the coarsening part we develop a new approximation algorithm for maximum weighted matching in general edge-weighted graphs. It calculates a matching with an edge weight of at least of the edge weight of a maximum weighted matching. Its time complexity is O(|E|), with |E| being the number of edges in the graph. Furthermore, we use the Helpful-Set strategy for the local improvement of partitions. For partitioning graphs with a regular degree of 2k into two parts, it guarantees an upper bound of ((k?1)/2)|V|+1 on the cut size of the partition, with |V| being the number of vertices. These quality methods used for the two parts of the multilevel approach lead to an efficient graph-partitioning concept.

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


On similarity-awareness in testing-based fault localization In the process of software development and maintenance, software debugging is an inevitable and time-consuming task. To accelerate software debugging, various approaches have been proposed to automate fault localization. Among them, testing-based fault-localization approaches are most promising, which use the execution information of many test cases to localize the faults. However, these existing testing-based fault-localization approaches ignore the similarity between test cases, which may harm the effectiveness of these approaches according to our previous research. Therefore, in this paper we propose a similarity-aware fault-localization approach, which takes each test case as a fuzzy set to deal with the similarity between test cases and calculates statements' suspicions based on the probability theory. To investigate whether SAFL can address the similarity issue effectively, we manually injected redundant test cases in a test suite and performed an experimental study on the original test suite and the test suite with redundancy, respectively. The experimental results demonstrate that in our experiments SAFL is an effective fault-localization approach, whether there is manually injected redundancy in the test suite. To compare SAFL with most existing testing-based fault-localization approaches, we performed another experimental study on Siemens program suite, which is extensively used in the evaluation of many other testing-based fault-localization approaches. This experimental study confirms the effectiveness of SAFL. Based on the two experimental studies, it seems that in our experiments SAFL cannot only deal with test suites containing much redundancy effectively but also perform effectively for test suites without much redundancy.

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

debugging
maintenance
fault localization
fuzzy set


Thermomechanical coupling in folded plates and non-smooth shells In this work we present the model for thermomechanical coupling in folded plates or non-smooth shells, which can be used for analysis of fire-resistance of cellular structures. For this purpose, a modified version of shell element including drilling degrees of freedom permits a detailed modeling combined with a constitutive model proposed in terms of the Saint-Venant multi-surface plasticity criterion. Thermomechanical coupling is also considered including radiative exchanges and operator split solution procedure with different time steps for each sub-problem. The model performance is illustrated by several numerical examples including fire-resistance of walls built with clay bricks.

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 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


an improved algorithm for computing the volume of the union of cubes Let C be a set of n axis-aligned cubes in ? 3 , and let U ( C ) denote the union of C . We present an algorithm that computes the volume of U ( C ) in time O ( n polylog( n )). The previously best known algorithm takes O ( n 4/3 log 2 n ) time.

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


Energy efficient distributed image compression in resource-constrained multihop wireless networks Efficient compression and transmission of images in a resource-constrained multihop wireless network is considered. Distributed image compression is proposed as a means to overcome the computation and/or energy limitation of individual nodes by sharing the processing of tasks. It has the additional benefit of extending the overall lifetime of the network by distributing the computational load among otherwise idle processors. Two design alternatives for energy efficient distributed image compression are proposed and investigated with respect to energy consumption and image quality. Simulation results show that the proposed scheme prolongs the system lifetime at a normalized total energy consumption comparable to the centralized image compression. (c) 2005 Elsevier B.V. All rights reserved.

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


Symbolic computation with finite quandles Algorithms are described and Maple implementations are provided for finding all quandles of order n, as well as computing all homomorphisms between two finite quandles or from a finitely presented quandle (e.g., a knot quandle) to a finite quandle, computing the automorphism group of a finite quandle, etc. Several of these programs work for arbitrary binary operation tables and hence algebraic structures other than quandles. We also include a stand-alone C program which finds quandles of order it and provide URLs for files containing the results for n = 6, 7 and 8. (c) 2006 Elsevier Ltd. All rights reserved.

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


Dynamic quorums for DHT-based enterprise infrastructures Peer-to-peer systems (M) have become a popular technique to design large-scale distributed applications in unmanaged inter-domain settings, such as file sharing or chat systems, thanks to their capabilities to self-organize and evenly split the load among peers. Recently, enterprises owning a large IT hardware and software infrastructure started looking at these P2P technologies as a means both to reduce costs and to help their technical divisions to manage huge number of devices characterized by a high level of cooperation and a relatively low churn. Gaining a quick exclusive access to the system for maintenance or auditing purposes in these enterprise infrastructures is a fundamental operation to be implemented. Conversely, this kind of operation is usually not an issue in the previously mentioned inter-domain setting, where peers are inherently independent and cannot be managed. In the context of classical distributed applications, quorum systems have been considered as a major building block for implementing many paradigms, from distributed mutual exclusion to data replication management. In this paper, we explore how to architect decentralized protocols implementing quorum systems in Distributed Hash Table based cooperative P2P networks. Our results show that quorum systems taken "as is" from the literature and directly applied to such networks are not scalable due to the high load imposed onto the underlying network. This paper introduces some design principles for both quorum systems and protocols using them that boost their scalability and performance. These design principles consist in a dynamic and decentralized selection of quorums and in the exposition and exploitation of internals of the DHT. As a third design principle it is also shown how to redesign quorum systems to enable efficient decentralization. We show that by combining these design principles in a cooperative environment with relatively low churn it is possible to minimize the imposed load in the system, in terms of sites contacted to obtain a quorum, and the latency of quorum acquisition. (C) 2008 Elsevier Inc. All rights reserved.

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

hierarchical majority
hierarchical grid
p2p systems


A Low-Diameter Unstructured P2P Overlay and Corresponding Search Algorithm Unstructured peer-to-peer networks are frequently used as the overlay in various middleware toolkits for emerging applications, from content distribution to query result caching to distributed collaboration. There are two main aspects in unstructured P2P system researches: (I)How to build a scalable and robust topology and (2) how to present a low cost and more efficient query algorithm. Though normally a search algorithm is independent of the topology, a good topology can greatly improve the performance of the search algorithm. However, most unstructured P2P systems can not combine the robustness with the efficiency and searching accuracy. The main contribution of the paper is to combine the researches on both topology and search algorithm. At first, a low-diameter unstructured P2P overlay called MPO with small world and power-law characteristics is presented. Detailed experiments show that current popular search algorithms can obtain better performances in MPO. Then, a new search algorithm based on the overlay is presented. We compared the new algorithm with popular search algorithms in the unstructured P2P systems. The results show that the algorithm is better than others in MPO according to several parameters. Thus, we draw a conclusion that the combination of the new search algorithm and the MPO has better performances than that of other search algorithm and other overlay.

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


A Generalization of Automorphism Classification of Cellular Automata As a concluding job in a series of studies on the automorphic classification of cellular automata (CA), a generalized automorphism called g-automorphism of CA is defined and investigated, where both of the permutations of the neighborhood and the arguments of the local function arc considered. First it is proved that the g-automorphisms constitute a group under semi-direct product. The group acts on the set of local functions and naturally induces a classification of CA such that every CA in a class has the same global properties up to As a computational example, a complete g-automorphic classification of ECA is given, where all 256 ECA rules are classified into 11 g-automorphism classes and 48 ECA rules are shown g-automorphic to rule 110 or universal up to permutation. This kind of algebraic study of classification must help to understand the mathematical nature of CA as a whole and to find new useful local functions efficiently.

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

neighborhood permutation automorphism classification eca

cellular automaton
semi-direct product
rule110


Numerical errors of explicit finite difference approximation for two-dimensional solute transport equation with linear sorption The numerical errors associated with explicit upstream finite difference solutions of two-dimensional advectionDispersion equation with linear sorption are formulated from a Taylor analysis. The error expressions are based on a general form of the corresponding difference equation. The numerical truncation errors are defined using Peclet and Courant numbers in the X and Y direction, a sink/source dimensionless number and new Peclet and Courant numbers in the XY plane. The effects of these truncation errors on the explicit solution of a two-dimensional advectiondispersion equation with a first-order reaction or degradation are demonstrated by comparison with an analytical solution in uniform flow field. The results show that these errors are not negligible and correcting the finite difference scheme for them results in a more accurate solution.

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

advectiondispersion-reaction equation
numerical methods
finite difference model


An improved gas-kinetic BGK finite-volume method for three-dimensional transonic flow During the past decade gas-kinetic methods based on the BGK simplification of the Boltzmann equation have been employed to compute fluid flow in a finite-difference or finite-volume context. Among the most successful formulations is the finite-volume scheme proposed by Xu [K. Xu, A gas-kinetic BGK scheme for the Navier-Stokes equations and its connection with artificial dissipation and Godunov method, J. Comput. Phys. 171 (48) (2001) 289-335]. In this paper we build on this theoretical framework mainly with the aim to improve the efficiency and convergence of the scheme, and extend the range of application to three-dimensional complex geometries using general unstructured meshes. To that end we propose a modified BGK finite-volume scheme, which significantly reduces the computational cost, and improves the behavior on stretched unstructured meshes. Furthermore, a modified data reconstruction procedure is presented to remove the known problem that the Chapman-Enskog expansion of the BGK equation fixes the Prandtl number at unity. The new Prandtl number correction operates at the level of the partial differential equations and is also significantly cheaper for general formulations than previously published methods. We address the issue of convergence acceleration by applying multigrid techniques to the kinetic discretization. The proposed modifications and convergence acceleration help make large-scale computations feasible at a cost competitive with conventional discretization techniques, while still exploiting the advantages of the gas-kinetic discretization, such as computing full viscous fluxes for finite volume schemes on a simple two-point stencil. (c) 2006 Elsevier Inc. All rights reserved.

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

navier-stokes equations
kinetic scheme
finite-volume scheme


A

method

for

the

accurate

and

smooth

approximation

of

standard

thermodynamic

functions

A

method

is

proposed

for

the

calculation

of

approximations

of

standard

thermodynamic

functions.

The

method

is

consistent

with

the

physical

properties

of

standard

thermodynamic

functions.

This

means

that

the

approximation

functions

are,

in

contrast

to

the

hitherto

used

approximations,

continuous

and

smooth

in

every

temperature

interval

in

which

no

phase

transformations

take

place.

The

calculation

algorithm

was

implemented

by

the

SmoothSTF

program

in

the

C++

language

which

is

part

of

this

paper.

Program

summary

Program

title:

SmoothSTF

Catalogue

identifier:

Program

summary

URL:

Program

obtainable

from:

CPC

Program

Library,

Queen's

University,

Belfast,

N.

Ireland

Licensing

provisions:

Standard

CPC

licence,

No.

of

lines

in

distributed

program,

including

test

data,

etc.:

No.

of

bytes

in

distributed

program,

including

test

data,

etc.:

Distribution

format:

tar.gz

Programming

language:

C++.

Computer:

Any

computer

with

gcc

version

compiler.

Operating

system:

Debian

GNU

Linux

The

program

can

be

run

in

operating

systems

in

which

the

gcc

compiler

can

be

installed,

see

RAM:

MB

are

sufficient

for

the

table

of

standard

thermodynamic

functions

with

lines

Classification:

Nature

of

problem:

Standard

thermodynamic

functions

(STF)

of

individual

substances

are

given

by

thermal

capacity

at

constant

pressure,

entropy

and

enthalpy.

STF

are

continuous

and

smooth

in

every

temperature

interval

in

which

no

phase

transformations

take

place.

The

temperature

dependence

of

STF

as

expressed

by

the

table

of

its

values

is

for

further

application

approximated

by

temperature

functions.

In

the

paper,

a

method

is

proposed

for

calculating

approximation

functions

which,

in

contrast

to

the

hitherto

used

approximations,

are

continuous

and

smooth

in

every

temperature

interval.

Solution

method:

The

approximation

functions

are

determined

by

coefficients

that

are

calculated

by

the

least

square

method

coupled

with

meeting

the

conditions

set

(calculation

of

minimum

with

equality

constraints).

To

calculate

the

coefficients

the

values

of

STF

derivatives

with

respect

to

temperature

must

be

available

in

addition

to

the

table

of

STF

values.

The

values

of

the

derivatives

are

established

using

cubic

splines

and

the

derivative

of

the

Lagrange

interpolation

polynomial.

Restrictions:

The

program

was

tested

and

is

used

on

the

assumption

that

the

upper

bound

of

the

temperature

interval

in

which

the

approximation

is

being

performed

does

not

exceed

kK.

This

value

is

sufficient

in

the

thermal

plasma

field.

For

temperatures

higher

than

kK

the

calculation

might

entail

difficulties,

which

could

however

be

removed

by

calculating

with

higher

than

double

precision.

Additional

comments:

The

program

package

includes

a

README

file

and

input

and

output

files

for

a

test

suite.

Running

time:

A

few

seconds,

if

the

approximation

is

being

determined

in

the

maximum

interval,

i.e.

from

ambient

temperature

to

kK.

(C)

Elsevier

B.V.

All

rights

reserved.

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

thermal plasma
standard thermodynamic functions

algorithms for functional approximation
atomic and molecular physics


Performance issues in WWW servers This paper evaluates techniques for improving operating system and network protocol software support for high-performance World Wide Web servers. We study approaches in three categories: i.e., new socket functions, per-byte optimizations, and per-connection optimizations. We examine two proposed socket functions, i.e., acceptex() and send-file(), comparing send_file()'s effectiveness with a combination of mmap() and writev(). We show how send_file() provides the necessary semantic support to eliminate copies and checksums in the kernel, and quantify the benefit of the function's header and close options. We also present mechanisms to reduce the number of packets exchanged in an HTTP transaction, both increasing server performance and reducing network utilization, without compromising interoperability. Results using WebStone show that our combination of mechanisms can improve server throughput by up to 64%, and can eliminate up to 33% of the packets in an HTTP exchange. Results with SURGE show an aggregate increase in server throughput of 25%.

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


Learning, action and consciousness: A hybrid approach toward modelling consciousness This paper is an attempt at understanding the issue of consciousness through investigating its functional role, especially in learning, and through devising hybrid neural network models that (in a qualitative manner) approximate characteristics of human consciousness. In doing so, the paper examines explicit and implicit learning in a variety of psychological experiments and delineates the conscious/unconscious distinction in terms of the two types of learning and their respective products. The distinctions are captured in a two-level action-based model CLARION. Some fundamental theoretical issues are also clarified with the help of the model. Comparisons with existing models of consciousness are made to accentuate the present approach. (C) 1997 Elsevier Science Ltd.

O O O B 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 B 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

neural networks
hybrid systems
reinforcement learning
procedural knowledge
rule extraction
dual representation


Information retrieval and machine learning for probabilistic schema matching Schema matching is the problem of finding correspondences (mapping rules, e.g. logical formulae) between heterogeneous schemas e.g. in the data exchange domain, or for distributed IR in federated digital libraries. This paper introduces a probabilistic framework, called sPLMap, for automatically learning schema mapping rules, based on given instances of both schemas. Different techniques, mostly from the IR and machine learning fields, are combined for finding suitable mapping candidates. Our approach gives a probabilistic interpretation of the prediction weights of the candidates, selects the rule set with highest matching probability, and outputs probabilistic rules which are capable to deal with the intrinsic uncertainty of the mapping process. Our approach with different variants has been evaluated on several test sets.

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


Conservative discretization of contact/impact problems for nearly rigid bodies A discretization scheme for contact/impact problems related to modeling of gears is proposed. The problem is first discretized in time and then a variational formulation for the resulted one step problem is developed. A finite element discretization completes the discretization process. The scheme is a reinterpretation of the general SimoLaursenChavla algorithm in the context of the rigid body motion superimposed with small elastic deformation; it conserves precisely the linear momentum and total energy, and approximately the angular momentum. The discretization method is illustrated with two numerical examples: the standard 1D impact problem for an elastic rod and a 2D model problem of an elastic wheel bouncing within a constraining box.

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

contact/impact problems
energy conservation
finite elements


Free-form geometric modeling by integrating parametric and implicit PDEs Parametric PDE techniques, which use partial differential equations (PDEs) defined over a 2D or 3D parametric domain to model graphical objects and processes, can unify geometric attributes and functional constraints of the models. PDEs can also model implicit shapes defined by level sets of scalar intensity fields. In this paper, we present an approach that integrates parametric and implicit trivariate PDEs to define geometric solid models containing both geometric information and intensity distribution subject to flexible boundary conditions. The integrated formulation of second-order or fourth-order elliptic PDEs permits designers to manipulate PDE objects of complex geometry and/or arbitrary topology through direct sculpting and free-form modeling. We developed a PDE-based geometric modeling system for shape design and manipulation of PDE objects. The integration of implicit PDEs with parametric geometry offers more general and arbitrary shape blending and free-form modeling for objects with intensity attributes than pure geometric models.

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

pde techniques
geometric modeling
solid models
shape blending


On Interval-Valued Fuzzy Metric Spaces In this paper, following the ideas of (continuous) t-norm and interval numbers, a concept of (continuous) interval-valued t-norm is proposed. Based on the interval-valued fuzzy set and the continuous interval-valued t-norm, we propose a notion of interval-valued fuzzy metric space, which is a generalization of fuzzy metric space in the sense of George and Veeramani [Fuzzy Sets and Systems 64 (1994): 395-399]. Meanwhile, we show that each metric induces an interval-valued fuzzy metric in certain conditions. Finally, we define a Hausdorff topology on an interval-valued fuzzy metric space and generalize some well-known conclusions of general metric spaces.

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

interval-valued fuzzy sets
interval-valued t-norm
interval-valued fuzzy metric spaces
complete


selfish load balancing and atomic congestion games We revisit a classical load balancing problem in the modern context of decentralized systems and self-interested clients. In particular, there is a set of clients, each of whom must choose a server from a permissible set. Each client selfishly wants to minimize its own latency (job completion time). A server's latency is inversely proportional to its speed, but it grows linearly with or, more generally, as the p th power of the number of clients matched to it. This interaction is naturally modeled as an atomic congestion game, which we call selfish load balancing . We analyze the Nash equilibria of this game and prove nearly tight bounds on the price of anarchy (worst-case ratio between a Nash solution and the social optimum). In particular, for linear latency functions, we show that if the server speeds are relatively bounded and the number of clients is large compared to the number of servers, then every Nash assignment approaches social optimum . Without any assumptions on the number of clients, servers, and server speeds, the price of anarchy is at most 2.5. If all servers have the same speed, then the price of anarchy further improves to 1 + 2/?3 ? 2.15. We also exhibit a lower bound of 2.01. Our proof techniques can also be adapted for the coordinated load balancing problem under L 2 norm, where it slightly improves the best previously known upper bound on the competitive ratio of a simple greedy scheme.

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

congestion game
price of anarchy
load balancing


oblivious gossiping in ad-hoc radio networks We study oblivious deterministic and randomized algorithms for gossiping in unknown radio networks. In oblivious algorithms the fact (or probability in case of randomized algorithm) that a processor transmits or not at a given time-step depends solely on its identification number, the total number of processors and the number of the time-step. We distinguish oblivious deterministic algorithms which allow only one processor to transmit in each time-step and term them singleton algorithms. We also distinguish oblivious randomized algorithms where in each time-step all processors have equal probability of transmission, and call them uniform. The merit of oblivious algorithms, especially the singleton and uniform ones, is that they are simple and easy to implement. We observe that gossiping in unknown radio networks on n nodes can be completed in time ( n - 1)( n - 2) + 4 by a singleton algorithm. On the other hand, we show that any singleton algorithm takes at least n 2 - &Ogr; ( n 7/4+? ) steps, for any ? > 0, whereas any deterministic oblivious algorithm requires at least n 2 /2 - &Ogr; ( n ) steps to complete the gossiping. We prove also that there is an oblivious deterministic algorithm for gossiping working in time n 2 - w ( n ). Next we show that a uniform oblivious randomized algorithm completes gossiping with high probability in time &Ogr; (min{ m, Dd } log 2 n ), where m denotes the number of edges, D is the eccentricity and d the maximum, in-degree in the network. Note that this upper bound is poly-logarithmic in n if D, d = &Ogr; ( poly log n ). The best related deterministic gossiping algorithm, in terms of performance expressed with respect to n , D , d , has been previously given by Clementi et al. [13], it works in time &Ogr; ( Dd 2 log 3 n ). We prove also that the upper bound attained by our uniform oblivious randomized algorithm is asymptotically optimal (up to a log-square factor) for a wide range of parameters m , D and d in the class of uniform oblivious randomized algorithms. Finally we observe that in case of symmetric networks the aforementioned oblivious randomized algorithm completes gossiping with high probability in time &Ogr; ( n log 2 n ) and that a known deterministic constructive broadcasting algorithm can be adopted to perform oblivious gossiping in time &Ogr; ( n 3/2 ).

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

processor network factor log performance identification probability case algorithm class

radio network
optimality
gossip
broadcast
timing
ad-hoc
randomized algorithm
completeness


Computation and visualization of three-dimensional soft tissue motion in the orbit This work presents a method to measure the soft tissue motion in three dimensions in the orbit during gaze. It has been shown that two-dimensional (2-D) quantification of soft tissue motion in the orbit is effective in the study of orbital anatomy and motion disorders [1]. However, soft tissue motion is a three-dimensional (3-D) phenomenon and part of the kinematics is lost in any 2-D measurement. Therefore, T1-weighted magnetic resonance (MR) imaging volume sequences are acquired during gaze and soft tissue motion is quantified using a generalization of the Lucas and Kanade optical now algorithm to three dimensions. New techniques have been developed for visualizing the 3-D flow field as a series of color-texture mapped 2-D slices or as a combination of volume rendering for display of the anatomy and scintillation rendering for the display of the motion field. We have studied the performance of the algorithm on four-dimensional volume sequences of synthetic motion, simulated motion of a static object imaged by MR, an MR-imaged rotating object and MR-imaged motion in the human orbit during gaze. The accuracy of the analysis is sufficient to characterize motion in the orbit and scintillation rendering is an effective visualization technique for 3-D motion in the orbit.

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

cinematic mri
multimodality visualization
optical flow


A weighted combination of stacking and dynamic integration In this paper we present a novel method that fuses the ensemble meta-techniques of stacking and dynamic integration for regression problems. We detail an introductory experimental analysis of the technique referred to as wMetaComb and compare its performance to single model linear regression, stacking and the dynamic integration technique of dynamic weighting with selection, where in the case of the ensembles the base models were also created using linear regression. The evaluation showed that wMetaComb returned the strongest performance.

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


Parametric reconfiguration improvement in non-iterative concurrent mechatronic design using an evolutionary-based approach Parametric reconfiguration plays a key role in non-iterative concurrent design of mechatronic systems. This is because it allows the designer to select, among different competitive solutions, the most suitable without sacrificing sub-optimal characteristics. This paper presents a method based on an evolutionary algorithm to improve the parametric reconfiguration feature in the optimal design of a continuously variable transmission and a five-bar parallel robot. The approach considers a solution-diversity mechanism coupled with a memory of those sub-optimal solutions found during the process. Furthermore, a constraint-handling mechanism is added to bias the search to the feasible region of the search space. Differential Evolution is utilized as the search algorithm. The results obtained in a set of five experiments performed per each mechatronic system show the effectiveness of the proposed approach.

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

evolutionary algorithms
multi-objective optimization


Comments on the erratum to "Supply planning model for remanufacturing system in reverse logistics environment" [Comput. Ind. Eng. 51 (2006) 279-287] To maximize the total cost of savings, a mixed-integer programming model for remanufacturing proposed by Kim et al. [Kim, K., Song, I., Kim, J., & Jeong, B. (2006). Supply planning model for remanufacturing system in reverse logistics environment. Computers & Industrial Engineering, 51, 279-287] was published in Computers & Industrial Engineering journal to decide optimally the quantity of parts to be processed at each remanufacturing facilities, the number of purchased parts from subcontractor. In this work, comments and suggestions are given to the published model of Kim, Song, Kim, and Jeong (2006). Comments like partial and complete disassembly, disassembly cost, optimum level of disassembly and finally, the modification of constraints are suggested in this work. (C) 2011 Elsevier Ltd. All rights reserved.

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


Developing automatic articulation, phonation and accent assessment techniques for speakers treated for advanced head and neck cancer Articulation model outperforms average human and features relate to tongue position. Voice quality model is competitive and features relate to pronunciation variation. Accent model is competitive and features relate to phonation and resonance. Models show variable success tracking change in perceptual scores over time.

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

automatic evaluation
perceptual evaluation
phonemic features
phonological features
ampex


Structural tendencies - Effects of adaptive evolution of complex (chaotic) systems We describe systems using Kauffman and similar networks. They are directed functioning networks consisting of finite number of nodes with finite number of discrete states evaluated in synchronous mode of discrete time. In this paper we introduce the notion and phenomenon of "structural tendencies". Along the way we expand Kauffman networks, which were a synonym of Boolean networks, to more than two signal variants and we find a phenomenon during network growth which we interpret as "complexity threshold". For simulation we define a simplified algorithm which allows us to omit the problem of periodic attractors. We estimate that living and human designed systems are chaotic (in Kauffman sense) which can be named - complex. Such systems grow in adaptive evolution. These two simple assumptions lead to certain statistical effects, i.e., structural tendencies observed in classic biology but still not explained and not investigated on theoretical way. For example, terminal modifications or terminal predominance of additions where terminal means: near system outputs. We introduce more than two equally probable variants of signal, therefore our networks generally are not Boolean networks. They grow randomly by additions and removals of nodes imposed on Darwinian elimination. Fitness is defined on external outputs of system. During growth of the system we observe a phase transition to chaos (threshold of complexity) in damage spreading. Above this threshold we identify mechanisms of structural tendencies which we investigate in simulation for a few different networks types, including scale-free BA networks.

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

kauffman networks
chaos
complexity
damage spreading
adaptive evolution


Thoracic cavity definition for 3D PET/CT analysis and visualization X-ray computed tomography (CT) and positron emission tomography (PET) serve as the standard imaging modalities for lung-cancer management. CT gives anatomical details on diagnostic regions of interest (ROIs), while PET gives highly specific functional information. During the lung-cancer management process, a patient receives a co-registered whole-body PET/CT scan pair and a dedicated high-resolution chest CT scan. With these data, multimodal PET/CT ROI information can be gleaned to facilitate disease management. Effective image segmentation of the thoracic cavity, however, is needed to focus attention on the central chest. We present an automatic method for thoracic cavity segmentation from 3D CT scans. We then demonstrate how the method facilitates 3D ROI localization and visualization in patient multimodal imaging studies. Our segmentation method draws upon digital topological and morphological operations, active-contour analysis, and key organ landmarks. Using a large patient database, the method showed high agreement to ground-truth regions, with a mean coverage=99.2% and leakage=0.52%. Furthermore, it enabled extremely fast computation. For PET/CT lesion analysis, the segmentation method reduced ROI search space by 97.7% for a whole-body scan, or nearly 3 times greater than that achieved by a lung mask. Despite this reduction, we achieved 100% true-positive ROI detection, while also reducing the false-positive (FP) detection rate by >5 > 5 times over that achieved with a lung mask. Finally, the method greatly improved PET/CT visualization by eliminating false PET-avid obscurations arising from the heart, bones, and liver. In particular, PET MIP views and fused PET/CT renderings depicted unprecedented clarity of the lesions and neighboring anatomical structures truly relevant to lung-cancer assessment.

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

chest
image segmentation
visualization
multimodal imaging

pet/ct
ct imaging
lung cancer
thoracic region segmentation
pulmonary imaging