Advantages of dilution in the connectivity of attractor networks in the brain A fundamental question about brain function is why the connectivity in the cortex is diluted, in that neurons in a local region of the neocortex and in the CA3 part of the hippocampal cortex typically have a probability of having a synaptic connection between them that is less than 0.1. In both these types of cortex, there is evidence that the excitatory interconnections between neurons are associatively modifiable, and that the system supports attractor dynamics that enable memories to be stored, which are used in for example short-term memory and in episodic memory. The hypothesis proposed is that the diluted connectivity allows biological processes that set up synaptic connections between neurons to arrange for there to be only very rarely more than one synaptic connection between any pair of neurons. If probabilistically there were more than one connection between any two neurons, it is shown by simulation of an autoassociation attractor network that such connections would dominate the attractor states into which the network could enter and be stable, thus strongly reducing the memory capacity of the network (the number of memories that can be stored and correctly retrieved), below the normal large capacity for diluted connectivity. Diluted connectivity between neurons in the cortex thus has an important role in allowing high capacity of memory networks in the cortex, and helping to ensuring that the critical capacity is not reached at which overloading occurs leading to an impairment in the ability to retrieve any memories from the network. This intra-area diluted connectivity complements the diluted connectivity in the feedforward connections between cortical areas that helps the representations built by competitive learning to be stable.

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

diluted connectivity
memory capacity
attractor network

cortical network
hippocampus
competitive network


Visualization of the tidal flow in Sasebo and Oomura Bays Sasebo and Oomura Bays situated in the northwest of Kyushu, Japan form a coupled bay linked by a channel. The tidal flow in and between these bays is visualized by the satellite images and the dispersion of Lagrangian particles is numerically studied. The satellite images are available to visualize the tidal flow at the mouth of Hario-seto from the maximum flood tide to the end of ebb tide at Tainoura. The seawater plume from the mouth of Hario-seto goes southeastward and then rotates anti-clockwise. The time of one rotation is about 6 to 7 periods. The plume extends about 10 km from the mouth of Hario-seto. Lagrangian particles in Sasebo Bay also flow into Oomura Bay through Haiki-seto.

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


path-based scheduling in a hardware compiler Hardware acceleration uses hardware to perform some software functions faster than it is possible on a processor. This paper proposes to optimize hardware acceleration using path-based scheduling algorithms derived from dataflow static scheduling, and from control-flow state machines. These techniques are applied to the MIPS-to-Verilog (M2V) compiler, which translates blocks of MIPS machine code into a hardware design represented in Verilog for reconfigurable platforms. The simulation results demonstrate a factor of 22 in performance improvement for simple self-looped basic blocks over the base compiler.

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 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 B


a stolen object detection and tracing system for mobile valuables The proposed system provides a mechanism of detecting the stealing of valuables, and integrates wireless sensor networks with a location service to trace stolen valuables through deployed cameras in an indoor environment. Compared with traditional surveillance systems, it is able to actively notify the security manager that monitored valuables are stole and show the current positions, and real-time images of those stolen valuables when theft cases occur.

O B I I 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

wireless sensor networks
stolen object detection


Flexible real-time mobile robotic architecture based on behavioural models Behaviour-based models have been widely used to represent mobile robotic systems, which operate in uncertain dynamic environments and combine information from several sensory sources. The specification of complex mobile robotic applications is performed in such models by combining deliberative goal-oriented planning with reactive sensor driven operations. Consequently, the design of mobile robotic architectures requires the combination of time-constrained activities with deliberate time-consuming components. Furthermore, the temporal requirements of the reactive activities are variable and dependent on the environment (i.e. recognition processes) and/or on application parameters (i.e. process frequencies depend on robot speed). In this paper, a real-time mobile robotic architecture to cope with the functional and variable temporal characteristics of behaviour-based mobile robotic applications is proposed. Run-time flexibility is a main feature of the architecture that supports the variability of the temporal characteristics of the workload. The system has to be adapted to the environmental conditions, by adjusting robot control parameters (i.e. speed) or the system load (i.e. computational time), and take actions depending on it. This influence is focused on the ability of the system to select the appropriate activity to be executed depending on the available time, and, to change its behaviour depending on the environmental information. The flexibility of the system is allowed thanks to the definition of a real-time task model and the design of adaptation mechanisms for the regulation of the reactive load. The improvement of the robot quality of service (QoS) is another important aspect discussed in the paper. The architecture incorporates a quality of service manager (QoSM) that allows dynamically monitor analyse and improve the robot performances. Depending on the internal state, on the environment and on the objectives, the robot performance requirements vary (i.e. when the environment is overloaded, global map processes generating high-quality maps are required). The QoSM receives the performance requirements of the robot, and by adjusting the reactive load, the system enables the necessary slack time to schedule the more suitable deliberative processes and hence fulfilling the robot QoS. Moreover, the deliberative load can be scheduled by different heuristic strategies that provide answers of varying quality.

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

mobile robots
autonomous guided vehicles
behavioural model
hybrid architecture
real-time system
scheduling algorithms


Paradigmatic shifts for exascale supercomputing As the next generation of supercomputers reaches the exascale, the dominant design parameter governing performance will shift from hardware to software. Intelligent usage of memory access, vectorization, and intranode threading will become critical to the performance of scientific applications and numerical calculations on exascale supercomputers. Although challenges remain in effectively programming the heterogeneous devices likely to be utilized in future supercomputers, new languages and tools are providing a pathway for application developers to tackle this new frontier. These languages include open programming standards such as OpenCL and OpenACC, as well as widely-adopted languages such as CUDA; also of importance are high-quality libraries such as CUDPP and Thrust. This article surveys a purposely diverse set of proof-of-concept applications developed at Los Alamos National Laboratory. We find that the capability level of the accelerator computing hardware and languages has moved beyond the regular grid finite difference calculations and molecular dynamics codes. More advanced applications requiring dynamic memory allocation, such as cell-based adaptive mesh refinement, can now be addressedand with more effort even unstructured mesh codes can be moved to the GPU.

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

exascale computing
heterogeneous architecture
gpgpu
cell-based adaptive mesh refinement


Evaluating geodesic active contours in microcalcifications segmentation on mammograms Microcalcification segmentation method based on geodesic active contours. Method incorporates radiologists knowledge in its final stage. 86.9% of microcalcifications were adequately segmented. Performance satisfactory for microcalcifications larger than 460?m. Modest performance when segmenting microcalcifications smaller than 460?m.

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

microcalcification
segmentation
geodesic active contours
radiologists knowledge


organizing computer systems for learnability and useability Methods for organizing computer systems are described. The goal of these methods is to produce systems which are easier to learn and use, both for the novice and the advanced user. A system utilizing these methods is being developed at Brown; This system is discussed in some detail.

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

system design
microprogramming
structure
modularity
interpretation


Analysis and computation for a class of semilinear elliptic boundary value problems In this paper, with the help of super-solutions and sub-solutions, we set up a general framework and get a positive threshold Lambda for solution existence and non-existence of a class of semilinear elliptic Dirichlet boundary value problems. Moreover, a result on multiplicity is obtained when lambda is large enough. We also give a numerical method to solve and visualize the positive solutions of the problem. Theoretical results are illustrated by numerical simulation. (C) 2012 Elsevier Ltd. 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

multiple solutions
bifurcation
sub-solution
super-solution
pseudo-arclength continuation


Blended Interaction Spaces for Distributed Team Collaboration In recent years there has been an introduction of sophisticated new video conferencing technologies (e.g., HP Halo, Cisco Telepresence) that have led to enhancements in the collaborative user experience over traditional video conferencing technologies. Traditional video conferencing set-ups often distort the shared spatial properties of action and communication due to screen and camera orientation disparities and other asymmetries. These distortions affect access to the common resources used to mutually organize action and communication. By contrast, new systems, such as Halo, are physically configured to reduce these asymmetries and orientation disparities, thereby minimizing these spatial distortions. By creating appropriate shared spatial geometries, the distributed spaces become "blended" where the spatial geometries of the local space continue coherently across the distributed boundary into the remote site, providing the illusion of a single unified space.Drawing on theories of embodied action and workplace design we discuss the importance of this geometric "blending" of space for distributed collaboration and how this is achieved in systems such as Halo. We then extend these arguments to explore the concept of Blended Interaction Spaces: blended spaces in which interactive groupware is incorporated in ways spatially consistent with the physical geometries of the video-mediated set-up. We illustrate this discussion through a system called BISi that introduces interactive horizontal and vertical multipoint surfaces into a blended video-mediated collaboration space.In presenting this system, we highlight some of the particular challenges of creating these systems arising from the spatial consequences of different interaction mechanisms (e.g., direct touch or remote control) and how they affect movement and spatial configuration of people in these spaces.

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


Performance evaluation of leveled probabilistic broadcasting in MANETs and wireless sensor networks In a mobile ad hoc network (MANET) or a wireless sensor network (WSN), a mobile node or sensor node can communicate with nodes outside of its transmission range by employing intermediate nodes as relays. To find a path to a specific destination node, the source node broadcasts route request packets that are forwarded to all other nodes. A simple flooding scheme is employed in AODV, where every node rebroadcasts these route request packets even if some of its neighbors have already received the requests, and thus the rebroadcasts may reach no additional nodes. To avoid such redundant packet relays, the authors propose a routing protocol based on a preassigned probability model. They compare their approach with AODV in terms of numerous metrics, including average number of rebroadcasts, average number of packet collisions, end-to-end delay, and throughput. Both analytical and simulation results show that their approach outperforms the AODV protocol for most cases.

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

manet
probabilistic broadcasting
routing
wireless sensor networks


Advection upwinding splitting method to solve a compressible two-fluid model In this study, the advection upwinding splitting method (AUSM) is modified for the resolution of two-phase mixtures with interfaces. The compressible two-fluid model proposed by Saurel and Abgrall is chosen as the model equations. Dense and dilute phases are described in terms of the volume fraction and equations of state to represent multi-phase mixtures. Test cases involving an air-water shock tube, water faucet, and dilute particulate turbulent flows through a 90 degrees bend are used to verify the current work. It is shown that the AUSM based on flux differences (AUSMD) contains the mechanism to correctly capture the contact discontinuity and interfaces between phases. In addition, a successful application to dilute particulate turbulence flows by the AUSMD is demonstrated. Copyright (C) 2001 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 O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O 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 B O O O O O O O O O O


Multivariate data analysis: quo vadis? I. Object-oriented data modelling (OODM) Industry and academe are characterized by steadily increasing huge amounts of data with very different data structures. Both static and dynamic data contexts need to be addressed. A new generic, flexible and comprehensive general data-modelling concept is needed to cope with these demands. During the past 20 years, object-oriented programming (OOP) has become a de facto industry standard of how programming tasks should be defined and carried out in the context of deterministic data modelling. We present here a first framework of analogous ideas for multivariate data analysis. A new strategy, object-oriented data modelling (OODM), is proposed which is invariant with respect to the specific data structures and the practical data context. We present a first delineation of meta-principles, ideas and stimulants for tomorrow's possible development paths of modelling, in which the fundamental data analysis unit is the generalized 'PLS object' in the OOP sense. The key novel aspect concerns inter-object information transfer, facilitated by 'root-sum-of-squares averaging' (RSSA), which uses w loading weights as between-object transfer agents. These features allow a powerful generalization beyond multiblock as well as hierarchical bilinear modelling to be laid out. The present part I outlines a first framework for the new data-modelling approach, while part II forms a complementing catalogue of specific options and possibilities when implementing the new principles. Copyright (C) 2003 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 O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

latent data structures
object-oriented programming
object-oriented data modelling
h-principle
h-object
updated
weighting
generalized bilinear data analysis
meta-principles


The water falls but the waterfall does not fall: New perspectives on objects, processes and events We challenge the widespread presumption that matter and objects are ontologically prior to processes and events, and also the less widespread but increasingly popular view that processes and events are ontologically prior to matter and objects. Instead we advance a third view according to which each of these pairs of categories is ontologically dependent on the other. In particular, taking a cue from an ontology of devices, we identify the object as an interface between those processes which are internal to it and those which are external to it and which it may be said to enact, thereby linking objects intrinsically to the processes in which they are involved as well as providing a more powerful determinant of object identity than more traditional, non-dynamic criteria based on demarcation from the environment. The internal processes are themselves external processes in relation to the components of the object which enact them, leading to a potentially open-ended recursive decomposition of both objects and processes in a complex web of mutual interdependency. We also discuss how matter is related to objects, and processes to events, bringing the four categories together in a diagram which clarifies the relations between them - often considered problematic - and establishes a framework for a highly general top-level ontology.

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


Geospatial and machine learning techniques for wicked social science problems: analysis of crash severity on a regional highway corridor The contention of this paper is that many social science research problems are too wicked to be suitably studied using conventional statistical and regression-based methods of data analysis. This paper argues that an integrated geospatial approach based on methods of machine learning is well suited to this purpose. Recognizing the intrinsic wickedness of traffic safety issues, such approach is used to unravel the complexity of traffic crash severity on highway corridors as an example of such problems. The support vector machine (SVM) and coactive neuro-fuzzy inference system (CANFIS) algorithms are tested as inferential engines to predict crash severity and uncover spatial and non-spatial factors that systematically relate to crash severity, while a sensitivity analysis is conducted to determine the relative influence of crash severity factors. Different specifications of the two methods are implemented, trained, and evaluated against crash events recorded over a 4-year period on a regional highway corridor in Northern Iran. Overall, the SVM model outperforms CANFIS by a notable margin. The combined use of spatial analysis and artificial intelligence is effective at identifying leading factors of crash severity, while explicitly accounting for spatial dependence and spatial heterogeneity effects. Thanks to the demonstrated effectiveness of a sensitivity analysis, this approach produces comprehensive results that are consistent with existing traffic safety theories and supports the prioritization of effective safety measures that are geographically targeted and behaviorally sound on regional highway corridors.

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

spatial analysis
machine learning
crash severity
spatial dependence
spatial heterogeneity


Design of lower-order IIR digital low-pass filters with flat monotonic passbands and equiripple stopbands An IIR digital low pass filter with flat monotonic passband, equiripple stopband and narrower transition bandwidth than that of Inverse Chebyshev digital filters of the same order is designed. The requisite equiripple stopband is realized by designing the filter in Deczkeys' w-plane. The characteristic functions are designed so as to have a root of multiplicity n at w = 0 to ensure the n degree of flatness of the passband, and to have a pair of complex conjugate roots with coordinates constrained such that the magnitude response of the passband attenuates monotonically. The freedom in the coordinate of the complex conjugate roots is exploited to minimize the transition bandwidth. The equations are derived that give the minimum transition bandwidth of the proposed filter, which is considerably narrower than that of Inverse Chebyshev filters. It is showen through practical numerical examples that the order of the proposed filter is as low as half that of the Inverse Chebyshev filter satisfying the same specification.

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 B I I O O O O

flat monotonic passband
inverse chebyshev filter

lower-order iir digital low-pass digital filter


Extending the two-stage information systems continuance model: incorporating UTAUT predictors and the role of context This study presents two extensions to the two-stage expectation-confirmation theory of information systems (IS) continuance. First, we expand the belief set from perceived usefulness in the original IS continuance model to include three additional predictors identified in the unified theory of acceptance and use of technology, namely effort expectancy, social influence and facilitating conditions. Second, we ground the IS continuance model in the context of transactional systems that involve transmission of personal and sensitive information and include trust as a key contextual belief in the model. To test the expanded IS continuance model, we conducted a longitudinal field study of 3159 Hong Kong citizens across two electronic government (e-government) technologies that enable citizens' access to government services. In general, the results support the expanded model that provides a rich understanding of the changes in the pre-usage beliefs and attitudes through the emergent constructs of disconfirmation and satisfaction, ultimately influencing IS continuance intention. Finally, we discuss the theoretical and practical implications of the expanded model.

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

unified theory of acceptance and use of technology (utaut)


robust, low-cost, non-intrusive sensing and recognition of seated postures In this paper, we present a methodology for recognizing seated postures using data from pressure sensors installed on a chair. Information about seated postures could be used to help avoid adverse effects of sitting for long periods of time or to predict seated activities for a human-computer interface. Our system design displays accurate near-real-time classification performance on data from subjects on which the posture recognition system was not trained by using a set of carefully designed, subject-invariant signal features. By using a near-optimal sensor placement strategy, we keep the number of required sensors low thereby reducing cost and computational complexity. We evaluated the performance of our technology using a series of empirical methods including (1) cross-validation (classification accuracy of 87\% for ten postures using data from 31 sensors), and (2) a physical deployment of our system (78\% classification accuracy using data from 19 sensors).

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

machine learning
ubiquitous computing
haptic interfaces
sensor technologies
personal technologies


Improving mixing rate with tempered transition for learning restricted Boltzmann machines A new training method for Restricted Boltzmann Machines (RBMs) is proposed. The new method is based on Tempered Transition which is used to sample from RBMs. Tempered Transition has strong ability for handling multimodal distributions. Tempered Transition based training method can achieve better mixing rate than the existing methods. Tempered Transition based training method can help approximate the likelihood gradient.

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

restricted boltzmann machines
tempered transition
mixing rate


Using biological markers to inform a clinically meaningful treatment response Combat veterans with posttraumatic stress disorder (PTSD) demonstrate less robust improvement following treatments than do civilians with PTSD. This paper discusses a theoretical model for evaluating treatment response based on the extent of change in biological markers of symptom severity or resilience between treatment initiation and termination. Such analysis permits a determination of biological change associated with the liberal criteria commonly used to determine treatment response in combat PTSD, and a comparison of this to the biological change associated with clinical response determined according to the conservative definition more appropriate to civilian PTSD. Interim data supporting the utility of this approach is presented based on preliminary analyses from our work in progress. We propose that future studies consider the unique consequences of combat trauma and develop treatments that incorporate the complex nature of the exposure and response characteristic of a veteran population.

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


Visibility Histograms and Visibility-Driven Transfer Functions Direct volume rendering is an important tool for visualizing complex data sets. However, in the process of generating 2D images from 3D data, information is lost in the form of attenuation and occlusion. The lack of a feedback mechanism to quantify the loss of information in the rendering process makes the design of good transfer functions a difficult and time consuming task. In this paper, we present the general notion of visibility histograms, which are multidimensional graphical representations of the distribution of visibility in a volume-rendered image. In this paper, we explore the 1D and 2D transfer functions that result from intensity values and gradient magnitude. With the help of these histograms, users can manage a complex set of transfer function parameters that maximize the visibility of the intervals of interest and provide high quality images of volume data. We present a semiautomated method for generating transfer functions, which progressively explores the transfer function space toward the goal of maximizing visibility of important structures. Our methodology can be easily deployed in most visualization systems and can be used together with traditional 1D and 2D opacity transfer functions based on scalar values, as well as with other more sophisticated rendering algorithms.

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

transfer functions
volume rendering
visibility
histograms


hardware counter driven on-the-fly request signatures Today's processors provide a rich source of statistical informationon application execution through hardware counters. In this paper, we explore the utilization of these statistics as request signaturesin server applications for identifying requests and inferring high-level request properties ( e.g. , CPU and I/O resource needs). Our key finding is that effective request signatures may be constructed using a small amount of hardware statistics while the request is still in an early stage of its execution. Such on-the-fly request identification and property inference allow guided operating system adaptation at request granularity ( e.g. , resource-aware request scheduling and on-the-fly request classification). We address the challenges of selecting hardware counter metrics for signature construction and providing necessary operating system support for per-request statistics management. Our implementation in the Linux 2.6.10 kernel suggests that our approach requires low overhead suitable for runtime deployment. Our on-the-fly request resource consumption inference (averaging 7\%, 3\%, 20\%, and 41\% prediction errors for four server workloads, TPC-C, TPC-H, J2EE-based RUBiS, and a trace-driven index search, respectively) is much more accurate than the online running-average based prediction (73-82\% errors). Its use for resource-aware request scheduling results in a 15-70\% response time reduction for three CPU-bound applications. Its use for on-the-fly request classification and anomaly detection exhibits high accuracy for the TPC-H workload with synthetically generated anomalous requests following a typical SQL-injection attack pattern.

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

anomaly detection
operating system adaptation
hardware counter
request classification


Numerical approximation of nonlinear fractional differential equations with subdiffusion and superdiffusion In this paper, we study the time-space fractional order (fractional for simplicity) nonlinear subdiffusion and superdiffusion equations, which can relate the matter flux vector to concentration gradient in the general sense, describing, for example, the phenomena of anomalous diffusion, fractional Brownian motion, and so on. The semi-discrete and fully discrete numerical approximations are both analyzed, where the Galerkin finite element method for the space Riemann-Liouville fractional derivative with order 1 + beta is an element of [1, 2] and the finite difference scheme for the time Caputo derivative with order alpha is an element of (0, 1) (for subdiffusion) and (1, 2) (for superdiffusion) are analyzed, respectively. Results on the existence and uniqueness of the weak solutions, the numerical stability, and the error estimates are presented. Numerical examples are included to confirm the theoretical analysis. During our simulations, an interesting diffusion phenomenon of particles is observed, that is, on average, the diffusion velocity for 0 < alpha < 1 is slower than that for alpha = 1, but the diffusion velocity for 1 < alpha < 2 is faster than that for alpha = 1. For the spatial diffusion, we have a similar observation. (C) 2011 Elsevier Ltd. All rights reserved.

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

subdiffusion
superdiffusion
caputo derivative
finite element method

time-space fractional diffusion equation


Designing and Implementing a Human-Robot Team for Social Interactions This study provides an in-depth analysis and practical solution to the problem of designing and implementing a human robot team for simple conversational interactions. Models for operation timing, customer satisfaction and customer robot interaction are presented, based on which a simulation developed to estimate fan-out and robot team performance. Techniques for managing interaction flow and operator task assignment are introduced. In simulation, the effectiveness of different techniques and factors related to team performance are studied. A case study on deploying multiple robots in a shopping mall is then presented to demonstrate the usefulness of our study in helping the design and implementation of social robots in real-world settings.

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


Multivalued type proximity measure and concept of mutual ismilarity value useful for clustering symbolic patterns In this paper, a novel similarity measure for estimating the degree of similarity between two patterns (described by interval type data) is proposed. The proposed measure computes the degree of similarity between two patterns and approximates the computed similarity value by a multivalued type data. Unlike conventional proximity matrices, the proximity matrix obtained through the application of the proposed similarity measure is not necessarily symmetric. Based on this unconventional similarity matrix a modified agglomerative method by introducing the concept of mutual similarity value (MSV) for clustering symbolic patterns is also presented. Experiments on various data sets have been conducted in order to study the efficacy of the proposed methodology. (C) 2004 Elsevier B.V. All rights reserved.

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

symbolic data analysis
proximity measures
interval valued data type
multivalued data type
clustering of data


Higher-order three-point boundary value problem on time scales In this paper, we consider a higher-order three-point boundary value problem on time scales. We study the existence of solutions of a non-eigenvalue problem and of at least one positive solution of an eigenvalue problem. Later we establish the criteria for the existence of at least two positive solutions of a non-eigenvalue problem. Examples are also included to illustrate our results.

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

time scale
dynamic equation
cone
fixed-point theorem


Schema mappings and agents' actions in P2P data integration system We propose specification of schema mappings and agents' actions in XML data integration task. We discuss the problem in a highly-dynamic environment consisting of a community of peer-to-peer cooperating partners (agents). Peers decide how to describe their local data, when to join and when to leave the system, how to communicate and share their information with partners. An agent responds to the query by asking its partners (friends), which are able to partly answer the query. All the answers are merged and. nal result is constructed. A peer propagates a query along semantic paths existing in the system. Semantic paths are determined by schema mappings defined between partners. We propose a method for specifying schema mappings and to translate them to XQuery expressions. Mappings are represented by means of logical formulas. We also propose a declarative specification of semantic-driven communication in the system. The specification is made in a peer-oriented extension of Prolog.

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


Adapting application execution in CMPs using helper threads In parallel to the changes in both the architecture domainthe move toward chip multiprocessors (CMPs)and the application domainthe move toward increasingly data-intensive workloadsissues such as performance, energy efficiency and CPU availability are becoming increasingly critical. The CPU availability can change dynamically due to several reasons such as thermal overload, increase in transient errors, or operating system scheduling. An important question in this context is how to adapt, in a CMP, the execution of a given application to CPU availability change at runtime. Our paper studies this problem, targeting the energy-delay product (EDP) as the main metric to optimize. We first discuss that, in adapting the application execution to the varying CPU availability, one needs to consider the number of CPUs to use, the number of application threads to accommodate and the voltage/frequency levels to employ (if the CMP has this capability). We then propose to use helper threads to adapt the application execution to CPU availability change in general with the goal of minimizing the EDP. The helper thread runs parallel to the application execution threads and tries to determine the ideal number of CPUs, threads and voltage/frequency levels to employ at any given point in execution. We illustrate this idea using four applications (Fast Fourier Transform, MultiGrid, LU decomposition and Conjugate Gradient) under different execution scenarios. The results collected through our experiments are very promising and indicate that significant EDP reductions are possible using helper threads. For example, we achieved up to 66.3%, 83.3%, 91.2%, and 94.2% savings in EDP when adjusting all the parameters properly in applications FFT, MG, LU, and CG, respectively. We also discuss how our approach can be extended to address multi-programmed workloads.

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

adaptive computing
edp reduction
runtime optimization


Transnational public sector knowledge networks: Knowledge and information sharing in a multi-dimensional context Sharing of knowledge, information, and practices across cultural and national boundaries has become a means to address critical global problems. As government agencies increasingly collaborate with international counterparts on these issues, transnational knowledge and information sharing networks grow in importance as mechanisms for collaboration. This paper explores the nature of transnational public sector knowledge networks (TPSKNs) and identifies critical contextual factors that shape their performance. In these networks, each participating organization operates within complex national, organizational, and information contexts. The contextual differences between participants produce distances in culture, politics, intentions, organizational factors, relationships, knowledge, resources, geography, and technology. These distances influence their ability to engage in the processes and interactions that are essential to network performance. The paper concludes with a conceptual dynamic model that accounts for the relationships among these factors that can guide further research in understanding knowledge and information sharing across national and cultural boundaries.

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

knowledge sharing
international networks


Inequalities of Hlder and Minkowski type for pseudo-integrals with respect to interval-valued ?-measures In the present paper, the Hlder and Minkowski type of inequality for the pseudo-integral of a real-valued function with respect to the interval-valued pseudo-additive measure is proven. Two cases of semirings are considered. In the first case, pseudo-operations (pseudo-addition and pseudo-multiplication) are set by a strictly monotone continuous function. In the second case, the pseudo-addition is the idempotent operation sup, and pseudo-multiplication is specified by a strictly monotone continuous function, as in the first case. Trivial and nontrivial examples of interval-valued pseudo-additive measures are provided, as well as Hlder and Minkowski type of inequalities with respect to those measures.

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

pseudo-operations
pseudo-integral
interval-valued measure
hlder type inequality
minkowski type inequality


Interleukin-1?Induced Extracellular Matrix Degradation and Glycosaminoglycan Release Is Inhibited by Curcumin in an Explant Model of Cartilage Inflammation Osteoarthritis (OA) is a degenerative and inflammatory disease of synovial joints that is characterized by the loss of articular cartilage, for which there is increasing interest in natural remedies. Curcumin (diferuloylmethane) is the main polyphenol in the spice turmeric, derived from rhizomes of the plant Curcuma longa. Curcumin has potent chemopreventive properties and has been shown to inhibit nuclear factor ?B-mediated inflammatory signaling in many cell types, including chondrocytes. In this study, normal articular cartilage was harvested from metacarpophalangeal and metatarsophalangeal joints of eight horses, euthanized for reasons other than research purposes, to establish an explant model mimicking the inflammatory events that occur in OA. Initially, cartilage explants (N= 8) were stimulated with increasing concentrations of the proinflammatory cytokine IL-1? to select effective doses for inducing cartilage degeneration in the explant model. Separate cartilage explants were then cotreated with IL-1? at either 10 ng/mL (n= 3) or 25 ng/mL (n= 3) and curcumin (0.1 ?mol/L, 0.5 ?mol/L, 1 ?mol/L, 10 ?mol/L, and 100 ?mol/L). After 5 days, the percentage of glycosaminoglycan (GAG) release from the explants was assessed using a dimethylmethylene blue colorimetric assay. Curcumin (100 ?mol/L) significantly reduced IL-1?-stimulated GAG release in the explants by an average of 20% at 10 ng/mL and 27% at 25 ng/mL back to unstimulated control levels (P < 0.001). Our results suggest that this explant model effectively simulates the proinflammatory cytokine-mediated release of articular cartilage components seen in OA. Furthermore, the evidence suggests that the inflammatory cartilage explant model is useful for studying the effects of curcumin on inflammatory pathways and gene expression in IL-1?-stimulated chondrocytes.

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

osteoarthritis cartilage inflammation polyphenol glycosaminoglycan cytokine curcumin


Databases for knowledge discovery ?: Examples from biomedicine and health care Examples are given of the use of large research databases for knowledge discovery. Such databases are not only increasingly used for research in the hard mathematics-based disciplines such as physics and engineering but also in more soft disciplines, such as sociology, psychology and, in general, the humanities. In between the hard and the soft disciplines lie disciplines such as biomedicine and health care, from which we have selected our illustrations. This latter area can be subdivided into: (1) fundamental biomedical research, related to the hard scientific approach; (2) clinical research, using both hard and soft data and (3) population-based research, which can be subdivided into prospective and retrospective research. The examples that we shall offer are representative for using computers in scientific research in general, but in medical and health informatics in particular.

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

knowledge discovery
clinical research
biomedical research

population-bases research
biomedical literature
fingerprints
genetics
epidemiology
primary care
critiquing
decision-support


Hamiltonian path embedding and pancyclicity on the Mobius cube with faulty nodes and faulty edges A graph G = (V, E) is said to be pancyclic if it contains fault-free cycles of all lengths from 4 to \V\ in G. Let F-v and F-e be the sets of faulty nodes and faulty edges of an n-dimensional Mobius cube MQ(n), respectively, and let F = F-v boolean OR F-e. A faulty graph is pancyclic if it contains fault-free cycles of all lengths from 4 to \V - F-v\. In this paper, we show that MQ(n) - F contains a fault-free Hamiltonian path when \F\ = 1. We also show that MQ(n) - F is pancyclic when \F\ = 2. Since MQ(n) is regular of degree n, both results are optimal in the worst case.

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


Characterization of the Rat INSL3 Receptor Abstract: Human LGR8, initially discovered as a low-affinity relaxin receptor, has now been characterized as the INSL3 receptor. To investigate LGR8 function in the rat, an LGR8 ortholog was identified in the rat genome, and the full-length sequence was cloned and expressed. Rat LGR8 bound INSL3 with high affinity, clearly demonstrating that it is the rat INSL3 receptor. Interestingly, native rat relaxin did not activate rat LGR8, indicating that relaxin is not an endogenous ligand for rat LGR8. LGR8 mRNA expression was demonstrated in the gubernaculum at the time of testis descent and in the testis associated with germ cells.

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


Exploring the design space of reliable multicast protocols for wireless mesh networks Many important applications in wireless mesh networks require reliable multicast communication, i.e., with 100% packet delivery ratio (PDR). Previously, numerous multicast protocols based on automatic repeat request (ARQ) have been proposed to improve the packet delivery ratio. However, these ARQ-based protocols can lead to excessive control overhead and drastically reduced throughput. In this paper, we present a comprehensive exploration of the design space for developing high-throughput, reliable multicast protocols that achieve 100% PDR. Motivated by the fact that 802.11 MAC layer broadcast, which is used by most wireless multicast protocols, offers no reliability, we first examine if better hop-by-hop reliability provided by unicasting the packets at the MAC layer can help to achieve end-to-end multicast reliability. We then turn to end-to-end solutions at the transport layer. Previously, forward error correction (FEC) techniques have been proved effective for providing reliable multicast in the Internet, by avoiding the control packet implosion and scalability problems of ARQ-based protocols. In this paper, we examine if FEC techniques can be equally effective to support reliable multicast in wireless mesh networks. We integrate four representative reliable schemes (one ARQ, one FEC, and two hybrid) originally developed for the Internet with a representative multicast protocol ODMRP and evaluate their performance. Our experimental results via extensive simulations offer an in-depth understanding of the various choices in the design space. First, compared to broadcast-based unreliable ODMRP, using unicast for per-hop transmission only offers a very small improvement in reliability under low load, but fails to improve the reliability under high load due to the significantly increased capacity requirement which leads to congestion and packet drop. Second, at the transport layer, the use of pure FEC can significantly improve the reliability, increasing PDR up to 100% in many cases, but can be inefficient in terms of the number of redundant packets transmitted. In contrast, a carefully designed ARQFEC hybrid protocol, such as RMDP, can also offer 100% reliability while improving the efficiency by up to 38% compared to a pure FEC scheme. To our best knowledge, this is the first in-depth study of high-throughput, reliable multicast protocols that provide 100% PDR for wireless mesh networks.

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

multicast reliability arq fec unicast odmrp


exploiting site-level information to improve web search Ranking Web search results has long evolved beyond simple bag-of-words retrieval models. Modern search engines routinely employ machine learning ranking that relies on exogenous relevance signals. Yet the majority of current methods still evaluate each Web page out of context. In this work, we introduce a novel source of relevance information for Web search by evaluating each page in the context of its host Web site. For this purpose, we devise two strategies for compactly representing entire Web sites. We formalize our approach by building two indices, a traditional page index and a new site index, where each "document" represents the an entire Web site. At runtime, a query is first executed against both indices, and then the final page score for a given query is produced by combining the scores of the page and its site. Experimental results carried out on a large-scale Web search test collection from a major commercial search engine confirm the proposed approach leads to consistent and significant improvements in retrieval effectiveness.

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


Numerical method for the wave and nonlinear diffusion equations with the homotopy perturbation method In this paper, the homotopy perturbation method and a modified homotopy perturbation method are used for analytical treatment of the wave equation and some nonlinear diffusion equations, respectively. Some examples are given to illustrate that a suitable choice of an initial solution can lead to the exact solution, this revealing the reliability and effectiveness of the method.

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

homotopy perturbation method
wave equation
nonlinear diffusion equations

hes polynomials
dalembert formula
approximate analytical solution
exact solutions


Synthesis, antimicrobial activity and QSAR studies of 2,5-disubstituted benzoxazoles In this study, a new series of 2,5-disubstituted benzoxazoles was synthesized and their structures were elucidated by elemental analysis, MASS, (1)H-NMR, (13)C-NMR and IR spectral data. Newly and previously synthesized 2,5-disubstituted benzoxazole derivatives were evaluated for antibacterial and antifungal activity against standard strains and their drug-resistant isolates. Microbiological results showed that the compounds presented a large spectrum of activity having MIC values of 250-7.8 mu gmL(-1) against the tested microorganisms. Among the newly synthesized derivatives 3-22, compound 11 was the most active against Candida krusei out of all; however, it was one dilution less potent than standard drug fluconazole. In addition, all the new and previous compounds were more active than standard drugs ampicillin trihydrate and rifampicin against Pseudomonas aeruginosa and its gentamicin-resistant isolate. The 2D-QSAR (Quantitative Structure-Activity Relationship) analysis of a set of newly and previously synthesized benzoxazoles tested for growth inhibitory activity against methicillin-resistant Staphylococcus aureus (MRSA) was also performed by using multivariable regression analysis. The activity contributions for substituent effects of these compounds were determined from the correlation equation for predictions of the lead optimization.

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


Random swap EM algorithm for Gaussian mixture models Expectation maximization (EM) algorithm is a popular way to estimate the parameters of Gaussian mixture models. Unfortunately, its performance highly depends on the initialization. We propose a random swap EM for the initialization of EM. Instead of starting from a completely new solution in each repeat as in repeated EM, we make a random perturbation on the solution before continuing EM iterations. The removal and addition in random swap are simpler and more natural than split and merge or crossover and mutation operations. The most important benefit of random swap is its simplicity and efficiency. RSEM needs only the number of swaps as a parameter in contrast to complicated parameter-setting in genetic-based EM. We show by experiments that the proposed algorithm is 963% faster in computation time compared to the repeated EM, 2083% faster than split and merge EM except in one case. RSEM is much faster but has lower log-likelihood than GAEM for synthetic data with a certain parameter setting. The proposed algorithm also reaches comparable result in terms of log-likelihood.

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

expectation maximization
random swap em
split and merge em

gaussian mixture model
genetic-based em
data clustering


The Design of Grids in Web Surveys Grid or matrix questions are associated with a number of problems in web surveys. In this article, we present results from two experiments testing the design of grid questions to reduce breakoffs, missing data, and satisficing. The first examines dynamic elements to help guide respondent through the grid, and on splitting a larger grid into component pieces. The second manipulates the visual complexity of the grid and on simplifying the grid. We find that using dynamic feedback to guide respondents through a multiquestion grid helps reduce missing data. Splitting the grids into component questions further reduces missing data and motivated underreporting. The visual complexity of the grid appeared to have little effect on performance.

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 B I 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


minimal finite automata from finite training sets This paper describes a solution to the following problem: Given a finite set of strings A over an alphabet ? and a positive integer n , find a deterministic finite automaton (DFA) with a minimal number of states that recognizes the strings in the given set but does not recognize any other strings of length less than n . It turns out that, for some sets of strings A and integers n , the DFA is not uniquely determined.

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


Understanding the limitations of S/MIME digital signatures for e-mails: A GUI based approach S/MIME (Secure/Multipurpose Internet Mail Extensions) is a well-known standard for secure e-mail exchange. S/MIME builds its identity management on e-mail addresses, rather than real names. This fact may sometimes cause sending a signed e-mail with a bogus name on it. Moreover, header information of a signed e-mail message, such as subject and name, can be altered without affecting the verifiability of the signature. This paper spots the details of such problems of S/MIME and discusses some solutions from both developer and user points of view. Moreover, GUI considerations about these problems are also analyzed in this paper. An ideal GUI is modeled and developed.

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

e-mail security
s/mime
digital certificates
security gui


Team-based care to improve control of hypertension in an inner city practice The purpose of this case study was to identify which intervention or interventions, if any, resulted in improved hypertension control in an intercity public practice. Data includes interventions, graphed chronologically and the results in the form of percentage of patients with controlled hypertension. Challenges to success included understaffing of the practice and significantly limited access to appointments. Also, the variety of patients' languages and cultures presented a challenge. We reached our target of 60% of patients meeting criteria for control of hypertension. Although we instituted several interventions and all cumulatively contributed to the outcome, the two likely to be most effective were the establishment of hypertension-only appointments with either primary providers or with nurses. Both of these interventions resulted in an increased number of available appointments and improved access to timely follow up.

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


The DNA double helix fifty years on This year marks the 50th anniversary of the proposal of a double helical structure for DNA by James Watson and Francis Crick. The place of this proposal in the history and development of molecular biology is discussed. Several other discoveries that occurred in the middle of the twentieth century were perhaps equally important to our understanding of cellular processes; however, none of these captured the attention and imagination of the public to the same extent as the double helix. The existence of multiple forms of DNA and the uses of DNA in biological technologies is presented. DNA is also finding increasing use as a material due to its rather unusual structural and physical characteristics as well as its ready availability.

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


Recruitment of reticulospinal neurones and steady locomotion in lamprey In lamprey, the supraspinal control of velocity is mainly accomplished by the reticulospinal (RS) system. During locomotion, RS neurones are rhythmically active with a cycle duration corresponding to the duration of the swim cycle. While the velocity of the muscular contraction wave changes as swimming velocity changes, the conduction velocity of RS axons remains constant. Thus, an action potential generated during a specific phase of the swim cycle will, depending on swimming velocity, provide input to a particular downstream segment during different phases of its rhythmic activity. In order to investigate the importance of this effect for the control of locomotion, the temporal and spatial characteristics of the propagation of the population of action potentials along RS axons in the spinal cord were investigated. The results suggest that if RS neurones are recruited independently of their sizes and conduction velocities, a phasic wave of action potentials in these fibers will reach some segments during the inhibited phase of their rhythmic activity. Such an input could hinder a smooth propagation of the contraction wave and disrupt swimming. In contrast, by recruiting successively larger and hence more rapidly conducting neurones for successively more rapid swimming, the phasic wave of action potentials may propagate with the same velocity as that of the muscular contraction wave. Under such conditions, reticulospinal activity would support and stabilise locomotion.

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

motor control
reticulospinal system
size principle


Modeling of stratigraphic architectural patterns in extensional settingstowards a conceptual model Our earlier studies on active continental extensional basins revealed that high-frequency changes in sea/lake-level, spatially heterogeneous subsidence/uplift and multiple sources of sediment supply with varying rates and directions are the main factors that influence the formation of stratigraphic architectural patterns. Thus, the evolving stratal geometry results from the sea/lake-level[time], subsidence[time, space] and sediment supply[time, space, direction, composition] functions. The stratigraphic simulation results presented here demonstrate that Type 1 and 2 unconformities and conformities may develop in segments of an extensional basin during a sea/lake-level fall depending on the local subsidence rates. These different surfaces can be time-equivalent along the basin margin. A sea/lake level rise can either form a highstand systems tract (HST) or a transgressive and an overlying highstand systems tract (HST), depending on the sediment supply. A decrease and a subsequent increase in sediment supply during a stable base level stand can produce the same architectural patterns (backstepping of transgressive systems tract (TST) and aggradational or progradational patterns of HST) as a rise in the base level at constant sediment supply. Stratigraphic architectures built from multiple sediment sources show a variety of patterns as responses to spatial and temporal changes in intensities of individual sediment supply sources. Some of the possible end members of these interfingering architectural patterns have been simulated and classified. Changes in direction of sediment supply may lead to the formation of onlap-surfaces similar to unconformities.

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

stratigraphic architecture
stratigraphic simulations
differential subsidence
multiple sediment supply


Improved PMI-based input variable selection approach for artificial neural network and other data driven environmental and water resource models We address the performance of the PMI IVS influenced by the normality of data. We improved the performance of the PMI IVS for non-normally distributed data. Conventional PMI IVS performs well only for data following Gaussian distribution. Bandwidth with reduced Gaussian assumption improves the accuracy of PMI IVS. Preliminary guidelines are developed for PMI IVS and successfully validated.

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

artificial neural networks
general regression neural networks
partial mutual information
kernel bandwidth
kernel density estimation
environment
hydrology and water resources


NEURAL NETWORKS FOR DISCRIMINATION AND MODELIZATION OF SPEAKERS This article reviews current research on neural network systems for speaker recognition tasks. We consider two main approaches, the first one relies on direct classification and the second on speaker modelization. The potential of connectionist models for speaker recognition is first presented and the main models are briefly introduced. We then present different systems which have been recently proposed for speaker recognition tasks. We discuss their respective performances and potentials and compare these techniques to more conventional methods like vector quantization and Hidden Markov models. The paper ends with a summary and suggestions for further developments.

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

predictive modeling
modular connectionist system
neural nets
hybrid system
identification
verification


Two-dimensional merging path generation using model predictive control A merging path generation method for automated vehicle merging is proposed. This method can make the relevant vehicles cooperate with each other with constraint accelerations, keep the vehicles in their lanes and generate collision free merging path. The merging problem is considered in the two-dimensional space. We set up the mathematic model of the system, formulate the two-dimensional merging problem as an optimization problem and solve it by model predictive control (MPC). To compare the simulation results with the practice, three typical cases were researched. In order to be more practical, the initial conditions of the cases were set according to the data obtained through analyzing the helicopter-shot video. The results represent that the MPC-controlled merging maneuver carried out safely and smoothly, and the relative positions after merging is also the same with the practical results in all the three representative conditions considered. The absolute values of the accelerations of the vehicles are all kept below a practical value 3m/s2. The importance of cooperation in merging maneuver can also be noticed in the simulation results. By letting the relevant vehicles cooperate, this control algorithm would generate collision free merging path even in the very severe condition. The computational time for the three cases is also short enough for the method to be implemented in actual situation.

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

automotive control
model predictive control (mpc)
optimal control


visibility culling for time-varying volume rendering using temporal occlusion coherence Typically there is a high coherence in data values between neighboring time steps in an iterative scientific software simulation; this characteristic similarly contributes to a corresponding coherence in the visibility of volume blocks when these consecutive time steps are rendered. Yet traditional visibility culling algorithms were mainly designed for static data, without consideration of such potential temporal coherency. In this paper, we explore the use of Temporal Occlusion Coherence (TOC) to accelerate visibility culling for time-varying volume rendering. In our algorithm, the opacity of volume blocks is encoded by means of Plenoptic Opacity Functions (POFs). A coherence-based block fusion technique is employed to coalesce time-coherent data blocks over a span of time steps into a single, representative block. Then POFs need only be computed for these representative blocks. To quickly determine the subvolumes that do not require updates in their visibility status for each subsequent time step, a hierarchical "TOC tree" data structure is constructed to store the spans of coherent time steps. To achieve maximal culling potential, while remaining conservative, we have extended our previous POF into an Optimized POF (OPOF) encoding scheme for this specific scenario. To test our general TOC and OPOF approach, we have designed a parallel time-varying volume rendering algorithm accelerated by visibility culling. Results from experimental runs on a 32-processor cluster confirm both the effectiveness and scalability of our approach.

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

plenoptic opacity function
time-varying data visualization
large data visualization


a declarative debugger of incorrect answers for constraint functional-logic programs Debugging is one of the essential parts of the software development cycle. However, the usual debugging techniques used in imperative languages such as the step by step execution often are not suitable for debugging declarative programming languages. We present here a graphical debugging environment for constraint lazy functional-logic programs based on declarative debugging . The debugger displays the computation tree associated with a computation which has produced an incorrect answer, and navigates it with the assistance of the user until the error, an incorrect program rule, is found out. The debugger supports programs including equality and disequality constraints.

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


Damage detection in an aircraft foam sandwich panel using nonlinear elastic wave spectroscopy A novel damage detection technique, based on nonlinear elastic wave spectroscopy (NEWS) approach, is presented in this paper. This technique detects the presence of structural changes by monitoring the presence of harmonics and sidebands generated by the interaction between a low frequency and a high frequency harmonic excitation signal, due to the nonlinear material behaviour caused by the presence of damage. The proposed methodology was tested on a sandwich plate after being impacted by a foreign object under low velocity impact conditions. The high frequency signal was modulated in amplitude and the changes of the structural response, in terms of harmonic and sidebands amplitude, were recorded. The spectra and time frequency representation (TFR) were evaluated using wavelet transformations (WT). The experimental harmonic and sidebands amplitude resulted in close agreement with the theoretical behaviour of nonlinear behaviour of damaged materials. More specifically, the 3rd harmonics of the low frequency signal component showed a quadratic dependence with the low frequency response amplitude, as predicted by the theory for a hysteretic nonlinear material. Differently, the experimental second sidebands of the high frequency signal resulted bounded by curves representing the second sideband behaviour for pure hysteretic material (lower bound) and classical nonlinear material (upper bound). In particular, for small low frequency response amplitudes, the experimental second sidebands tended to be closer to the classical nonlinear material curve, while for the largest amplitudes investigated the response resembled a hysteretic material behaviour. The results showed that the proposed methodology was capable of detecting successfully the presence of impact damage and can be used as a first assessment of the presence of damage in aircraft structures where the presence of damage should be quickly estimated.

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

nonlinear elastic wave spectroscopy
harmonics
sidebands
impact damage
sandwich panel


Application of Taguchi method for the multi-objective optimization of aluminium foam manufacturing parameters In this study the Taguchi method is used to find the optimal process parameters for aluminium foam manufacturing. Porous metals are the unique materials used for light weight structural components, for filters and electrodes and for shock or sound absorbing products. Recently, interesting foaming technology developments have proposed metallic foams as a valid commercial chance. Metallic foam manufacturing techniques include solid state powder methods, gas blowing processes, metal deposition onto a polymer precursor and liquid state processing. The aluminium foams presented in this study are produced by the powder metallurgy route starting from aluminium powders with titanium hydride as the foaming agent. During the experimental work, many samples are made by utilizing the combination of process parameters based on Taguchi orthogonal design. Three manufacturing parameters are studied: the silicon carbide content in powder mixture, the compaction pressure and the foaming temperature. The Taguchi method is applied to design an orthogonal experimental array and a multi-objective optimization approach is then proposed by simultaneously minimizing the relative density and maximizing the absorbed energy. Verification test is also performed to prove the effectiveness of the presented technique.

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

aluminium foam
powder metallurgy
taguchi method


Optimal power flow solution using improved harmony search method This paper describes the improved harmony search method (IHS) to solve optimal power flow (OPF) problems. The harmony search is one of meta-heuristic search methods inspired by the improvisation of musicians developed by Geem (2001) [23]. The proposed algorithm was tested with five standard IEEE test systems (6-bus, 14-bus, 30-bus, 57-bus and 118-bus test systems). The tests were divided into smooth and non-smooth fuel-cost cases. The comparisons among solutions obtained by sequential quadratic programming (SQP), genetic algorithms (GA) and IHS were conducted. As revealed from the simulated results, the effectiveness of the IHS for solving OPF problems was confirmed.

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

optimal power flow
improved harmony search
sequential quadratic programming
genetic algorithms


Federated grid computing with interactive service-oriented programing Improvements in distributed computing, and the technologies that enable them, have led to significant advancements in middleware functionality and quality, mainly through networking and protocols. However, the distributed programing style has changed little over the years. Most programs are still written line per line of code in languages such as C, C++, and Java. These conventional programs that can provide grid operations and grid data can be considered as common grid resources and shared by research and education communities worldwide. However, there are no relevant programing methodologies to utilize efficiently these shared service providers as a potentially vast grid repository, except through the manual writing of code. Realization of the potential of grid computing requires significant improvements in grid programing methodologies. The Grid interactive service-oriented (GISO) methodology presented provides a programming environment with development tools that permit true interactive grid programming. The GISO approach permits the different elements of programming to be stored, reused, aggregated, and executed with concurrency and a grid-level control strategy not achievable in the conventional programming languages.

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

concurrent engineering
engineering analysis
service-oriented computing
object-oriented computing
service orchestration


Enhancing IEEE 802.11 MAC via a Sender-Initiated Reservation The IEEE 802.11 MAC adopted a collision avoidance mechanism in which contending stations should wait a random backoff time before sending a frame. While the algorithm reduces the collision probability in general, a large number of stations may still experience heavy collisions thus decrease the throughput. In this paper, we propose a simple reservation scheme for enhancing the performance of multiple access in 802.11 MAC: when a transmitter sends a frame, if it has another frame to send in its output queue, it may reserve an additional time that is needed to send the next frame and receive an ACK for the frame. Thus a sender can occupy the medium for two data frames, while reducing the collision probability and improving channel utilization via the reservation. We develop a mathematical model to analyze the performance of proposed scheme, and perform simulations to evaluate its performance compared with the original MAC.

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


issues on the design of vehicular node positioning based on doppler-shifted frequency measurement on highway Positioning plays a central role in location-based services. In designing such a method of highway applications, it is of paramount importance to provide a quick and precise positioning service. Such design considerations can help reduce the probability of accidents and other traffic troubles. This paper presents a novel and practical vehicular node positioning method which can achieve a higher accuracy, more quickness and more reliability than the existing global-positioning-system-based positioning solutions by making use of doppler-shifted frequency measurements taken by vehicular node itself. This positioning method uses infrastructure nodes which are placed on the roadside every several kilometers as radiation sources to estimate the relative distance and correlative angle of the vehicular node to the infrastructure node instantaneously. Through coordinate conversion, we get the absolute coordinates of vehicular node based on known absolute coordinates of infrastructure node. We also analyze the maximum distance of neighbor infrastructure nodes in order to ensure a high accuracy. In addition, simulation results demonstrate that the performance of our method with extended Kalman filtering (EKF) is superior to the method without EKF and DGPS.

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


Selective advantage of recombination in evolving protein populations: A lattice model study Recent research has attempted to clarify the contributions of several mutational processes, such as substitutions or homologous recombination. Simplistic, tractable protein models, which determine the compact native structure phenotype from the sequence genotype, are well-suited to such studies. In this paper, we use a lattice-protein model to examine the effects of point mutation and homologous recombination on evolving populations of proteins. We find that while the majority of mutation and recombination events are neutral or deleterious, recombination is far more likely to be beneficial. This results in a faster increase in fitness during evolution, although the final fitness level is not significantly changed. This transient advantage provides an evolutionary advantage to subpopulations that undergo recombination, allowing fixation of recombination to occur in the population.

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

homologous protein recombination
introns
lattice-protein


VIRUS: a pseudo-framing method for cell-based interfaces This paper presents the coding scheme and the timing recovery method of an interface for high-speed cell-based networks. The synchronization technique used in this interface is based on the functionality resulting from combining functions of the fiber channel with the basic features of pure asynchronous transfer mode. The main advantage of this interface is its implementability at high transmission rates, since most of its functions, like cell delineation and cell header error detection and correction, are performed at byte-level by using a pseudo-framing structure. The paper presents the basic principles of this interface, the analytic formulas for calculating its mean synchronization time under various traffic conditions and describes how the various parameters affect the method's performance. (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 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


Generalized Schultz iterative methods for the computation of outer inverses We consider a general matrix iterative method of the type Xk+1=Xkp(AXk) X k + 1 = X k p ( A X k ) for computing an outer inverse A R ( G ) , N ( G ) ( 2 ) , for given matrices A?Cmn A ? C m n and G?Cnm G ? C n m such that AR(G)?N(G)=Cm A R ( G ) ? N ( G ) = C m . Here p(x) p ( x ) is an arbitrary polynomial of degree d d . The convergence of the method is proven under certain necessary conditions and the characterization of all methods having order r r is given. The obtained results provide a direct generalization of all known iterative methods of the same type. Moreover, we introduce one new method and show a procedure how to improve the convergence order of existing methods. This procedure is demonstrated on one concrete method and the improvement is confirmed by numerical examples.

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 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 I 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

outer inverse
iterative methods
convergence

moorepenrose inverse
drazin inverse
schultz method


A unifying information-theoretic framework for independent component analysis We show that different theories recently proposed for independent component analysis (ICA) lead to the same iterative learning algorithm for blind separation of mixed independent sources. We review those theories and suggest that information theory can be used to unify several lines of research. Pearlmutter and Parra [1] and Cardoso [2] showed that the infomax approach of Bell and Sejnowski [3] and the maximum likelihood estimation approach are equivalent. We show that negentropy maximization also has equivalent properties, and therefore, all three approaches yield the same learning rule for a fixed nonlinearity. Girolami and Fyfe [4] have shown that the nonlinear principal component analysis (PCA) algorithm of Karhunen and Joutsensalo [5] and Oja [6] can also be viewed from information-theoretic principles since it minimizes the sum of squares of the fourth-order marginal cumulants, and therefore, approximately minimizes the mutual information [7]. Lambert [8] has proposed different Bussgang cost functions for multichannel blind deconvolution. We show how the Bussgang property relates to the infomax principle. Finally, we discuss convergence and stability as well as future research issues in blind source separation. (C) 2000 Elsevier Science Ltd. All rights reserved.

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

blind source separation
ica
maximum likelihood estimation


Enhancement of Coupled Multichannel Images Using Sparsity Constraints We consider the problem of joint enhancement of multichannel images with pixel based constraints on the multichannel data. Previous work by Cetin and Karl introduced nonquadratic regularization methods for SAR image enhancement using sparsity enforcing penalty terms. We formulate an optimization problem that jointly enhances complex-valued multichannel images while preserving the cross-channel information, which we include as constraints tying the multichannel images together. We pose this problem as a joint optimization problem with constraints. We first reformulate it as an equivalent (unconstrained) dual problem and develop a numerically-efficient method for solving it. We develop the Dual Descent method, which has low complexity, for solving the joint optimization problem. The algorithm is applied to both an interferometric synthetic aperture radar (IFSAR) problem, in which the relative phase between two complex-valued images indicate height, and to a synthetic multimodal medical image example.

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

multichannel images
nonquadratic regularization
optimization

interferometric synthetic aperture radar (ifsar)


Optimal Swarming for Massive Content Distribution A distinct trend has emerged that the Internet is used to transport data on a more and more massive scale. Capacity shortage in the backbone networks has become a genuine possibility, which will be more serious with fiber-based access. The problem addressed in this paper is how to conduct massive content distribution efficiently in the future network environment, where the capacity limitation can equally be at the core or the edge. We propose a novel technique as a main content transport mechanism to achieve efficient network resource utilization. The technique uses multiple trees for distributing different file pieces, which at the heart is a version of swarming. In this paper, we formulate an optimization problem for determining an optimal set of distribution trees as well as the rate of distribution on each tree under bandwidth limitation at arbitrary places in the network. The optimal solution can be found by a distributed algorithm. The results of the paper not only provide stand-alone solutions to the massive content distribution problem, but should also help the understanding of existing distribution techniques such as BitTorrent or FastReplica.

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

peer-to-peer networks
multicast
bandwidth allocation


INVERSE STATISTICS AND ASSET ALLOCATION EFFICIENCY In this paper using inverse statistics analysis, the effect of investment horizon on the efficiency of portfolio selection is examined. Inverse statistics analysis is a general tool also known as probability distribution of exit time that is used for detecting the distribution of the time in which a stochastic process exits from a zone. This analysis was used in Refs. 1 and 2 for studying the financial returns time series. This distribution provides an optimal investment horizon which determines the most likely horizon for gaining a specific return. Using samples of stocks from Tehran Stock Exchange (TSE) as an emerging market and S&P 500 as a developed market, effect of optimal investment horizon in asset allocation is assessed. It is found that taking into account the optimal investment horizon in TSE leads to more efficiency for large size portfolios while for stocks selected from S&P 500, regardless of portfolio size, this strategy does not only not produce more efficient portfolios, but also longer investment horizons provides more efficiency.

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

inverse statistics
investment horizon
asset allocation