Using genetic algorithm based knowledge refinement model for dividend policy forecasting Dividend policy is one of most important managerial decisions affecting the firm value. Although there are many studies regarding decision-making problems, such as credit policy decisions through bankruptcy prediction and credit scoring, there is no research, to our knowledge, about dividend prediction or dividend policy forecasting using machine learning approaches in spite of the significance of dividends. For dealing with the problems involved in literature, we suggest a knowledge refinement model that can refine the multiple rules extracted through rule-based algorithms from dividend data sets by utilizing genetic algorithm (GA). The new technique, called GAKR (genetic algorithm knowledge refinement), aims to combine the advantages of both knowledge consolidation and GA. The main result of the cross-validation procedure is the average accuracy rate of prediction in the five sets over the five iterations. The experiments show that GAKR model always outperforms other models in the performance of dividend policy prediction; we can predict future dividend policy more correctly than any other models. The major advantages of GAKR model can be summarized as follows: (1) Classification process of GAKR can be very fast with a compact set of rules. In other words, fast training mechanism of GAKR is possible regardless of data set sizes. (2) Multiple rules extracted by GAKR development process are much simpler and easier to understand. Moreover, GAKR model can discriminate redundant rules and inconsistent rules.

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

dividend policy
genetic algorithm
knowledge refinement
gakr model


Modeling Embodied Visual Behaviors To make progess in understanding human visuomotor behavior, we will need to understand its basic components at an abstract level. One way to achieve such an understanding would be to create a model of a human that has a sufficient amount of complexity so as to be capable of generating such behaviors. Recent technological advances have been made that allow progress to be made in this direction. Graphics models that simulate extensive human capabilities can be used as platforms from which to develop synthetic models of visuomotor behavior. Currently, such models can capture only a small portion of a full behavioral repertoire, but for the behaviors that they do model, they can describe complete visuomotor subsystems at a useful level of detail. The value in doing so is that the body's elaborate visuomotor structures greatly simplify the specification of the abstract behaviors that guide them. The net result is that, essentially, one is faced with proposing an embodied "operating system" model for picking the right set of abstract behaviors at each instant. This paper outlines one such model. A centerpiece of the model uses vision to aid the behavior that has the most to gain from taking environmental measurements. Preliminary tests of the model against human performance in realistic VR environments show that main features of the model show up in human behavior.

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

theory
experimentation
visual routines
visual attention
reinforcement learning


A non-overlapping domain decomposition method for the advection-diffusion problem The application of a non-overlapping domain decomposition method to the solution of a stabilized finite element method for elliptic boundary value problems is considered. We derive an a-posteriori error estimate which bounds the error on the subdomains by the interface error of the subdomain solutions. As a by-product, some foundation is given to the design of the interface transmission condition. Numerical results support the theoretical results. Furthermore, we adapt a recent result on a-posteriori estimates for singular perturbation problems in order to obtain an a-posteriori estimate For the discrete subdomain solutions. AMS Subject Classifications: 65N55, 65N30.

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

interface condition
a posteriori error estimates


Extending software component models with the masterworker paradigm Recent advances in computing and networking technologiessuch as multi-core processors and high bandwidth wide area networkslead parallel infrastructures to reach a higher degree of complexity. Programmers have to face with both parallel and distributed programming paradigms when designing an application. This is especially true when dealing with e-Science applications. Moreover, as parallel processing is moving to the mainstream, it does not seem appropriate to rely on low-level solutions requiring expert knowledge. This paper studies how to combine modern programming practices such as those based on software components and one of the most important parallel programming paradigms which is the well-known masterworker paradigm. The goal is to provide a simple and resource transparent model while enabling an efficient utilization of resources. The paper proposes a generic approach to embed the masterworker paradigm into software component models and describes how this generic approach can be implemented within an existing software component model. The overall approach is validated with synthetic experiments on clusters and the Grid5000 testbed.

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

software component
masterworker
clusters


Study of optimal combination between SFCL location and PSS type to improve power system transient stability Superconducting Fault Current Limiter (SFCL). Optimal combination between SFCL location and power system stabilizer. Power system stability. Short-circuit fault in electrical power system.

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

power system stabilizer
superconducting fault current limiter
system stability


Trigonometrically fitted two-step hybrid methods for special second order ordinary differential equations The purpose of this paper is to derive two-step hybrid methods for second order ordinary differential equations with oscillatory or periodic solutions. We show the constructive technique of methods based on trigonometric and mixed polynomial fitting and consider the linear stability analysis of such methods. We then carry out some numerical experiments underlining the properties of the derived classes of methods. (C) 2010 IMACS. Published by Elsevier B.V. All rights reserved.

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

two-step hybrid methods
trigonometrical fitting


Bounds on delays and queue lengths in input-queued cell switches In this article, we develop a general methodology, mainly based upon Lyapunov functions, to derive bounds on average delays, and on averages and variances of queue lengths in complex systems of queues. We apply this methodology to cell-based switches and routers, considering first output-queued (OQ) architectures, in order to provide a simple example of our methodology, and then both input-queued (IQ), and combined input/output queued (CIOQ) architectures. These latter switching architectures require a scheduling algorithm to select at each slot a subset of input-buffered cells that can be transferred toward Output ports. Although the stability proper-ties (i.e., the limit throughput) of IQ and CIOQ cell-based switches were already studied for several classes of scheduling algorithms, very few analytical results concerning cell delays or queue lengths are available in the technical literature. We concentrate on Maximum Weight Matching (MWM) and Maximal Size Matching (mSM) scheduling algorithms; while the former was proved to maximize throughput, the latter allows simpler implementation. The derived bounds are shown to be rather tight when compared to simulation 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 O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O 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

performance evaluation
delay bounds
input queued switches


virtual memories for mini-computers This paper is concerned with the application and implementation of virtual memory systems on mini-computers. The system constraints and their effect on the design parameters are discussed in detail and a general design philosophy is developed. A specific implementation, both software and hardware, of a virtual memory system on a PDP-11/20 is described. The final system makes a machine with 8K of core and a small disk appear to the user as an off-the-shelf 32K computer with the capability of banking as many 32K sections as the disk can support. Memory protection is also available.

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


An efficient on-the-fly cycle collection A reference-counting garbage collector cannot reclaim unreachable cyclic structures of objects. Therefore, reference-counting collectors either use a backup tracing collector infrequently, or employ a cycle collector to reclaim cyclic structures. We propose a new concurrent cycle collector, one that runs concurrently with the program threads, imposing negligible pauses (of around 1ms) on a multiprocessor. Our new collector combines a state-of-the-art cycle collector [Bacon and Rajan 2001] with sliding-views collectors [Levanoni and Petrank 2001, 2006; Azatchi et al. 2003]. The use of sliding views for cycle collection yields two advantages. First, it drastically reduces the number of cycle candidates, which in turn drastically reduces the work required to record and trace these candidates. Consequentially, a large improvement in cycle collection efficiency is achieved. Second, it eliminates the theoretical termination problem that appeared in the earlier concurrent cycle collector. There, a rare race may delay the reclamation of an unreachable cyclic structure forever. The sliding-views cycle collector guarantees reclamation of all unreachable cyclic structures.

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

languages
algorithms
programming languages
memory management
garbage collection
reference counting
concurrent cycle collection
runtime systems


Metrics for evaluating distributed manufacturing control systems In this paper, two classes of metrics are proposed that can be used to evaluate alternative manufacturing control architectures: those dealing with the controlled system (i.e. the manufacturing system) and those dealing with the control system. In order to illustrate the use of these metrics, the problem of scheduling a simple manufacturing cell is tackled using two test control architectures and the performance of these alternative approaches is evaluated using a modular discrete-event simulation model. The results of the paper suggest that it is worthwhile to use both manufacturing and control system performance measure to evaluate alternative control architectures, especially when considering dynamic architectures such as a Holonic Manufacturing System (HMS; i.e. architectures that adapt to changes in the manufacturing environment). (C) 2003 Elsevier Science B.V. All rights reserved.

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

distributed control systems
performance metrics


A modular architecture for nodes in wireless sensor networks The growth of sensor networks during the last years is a fact and within this field, wireless sensor networks are growing particularly as there are many applications that demand the use of many nodes, even hundreds or thousands. More and more applications are emerging to solve several problems in data acquisition and control in different environments, taking advantage of this technology. In this context, hardware design of the sensor network node becomes critical to satisfy the hard constraints imposed by wireless sensor networks, like low power consumption, low size and low cost. Moreover, these nodes must be capable of sensing, processing and communicating physical parameters, becoming true smart sensors in a network. With this goal in mind, we propose a modular architecture for the nodes, composed of four layers: communication, processing, power supply and sensing. The purpose is to minimize the redesign effort as well as to make the node flexible and adaptable to many different applications. In a first prototype of the node, we present a node with a mixed design based on a microcontroller and an FPGA for the processing layer and Bluetooth technology for communications.

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

wireless sensor networks
modular architecture
sensor network node


Power saving and fault-tolerance in real-time critical embedded systems In this paper, a method with the double purpose of reducing the consumption of energy and giving a deterministic guarantee on the fault tolerance of real-time embedded systems operating under the Rate Monotonic discipline is presented. A lower bound exists on the slack left free by tasks being executed at their worst-case execution time. This deterministic slack can be redistributed and used for any of the two purposes. The designer can set the trade-off point between them. In addition, more slack can be reclaimed when tasks are executed in less than their worst-case time. Fault-tolerance is achieved by using the slack to recompute the faulty task. Energy consumption is reduced by lowering the operating frequency of the processor as much as possible while meeting all time-constraints. This leads to a multifrequency method; simulations are carried out to test it versus two single frequency methods (nominal and reduced frequencies). This is done under different trade-off points and rates of faults occurrence. The existence of an upper bound on the overhead caused by the transition time between frequencies in Rate Monotonic scheduled real-time systems is formally proved. The method can also be applied to multicore or multiprocessor systems.

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


Oxygen consumption, heat production, and muscular efficiency during uphill and downhill walking Oxygen consumption, heat production, and muscular efficiency for walking are parameters important to know for ergonomics models and equipment design. Most of these assume that the oxygen consumption and heat production of downhill walking are the same as for uphill walking. Eight subjects wearing insulating clothing walked on a treadmill at three uphill and three downhill grades, and at level grade at a rate of 1.1m/s. Oxygen consumption was calculated from steady state measurements of respiratory minute volume and oxygen percentage. Heat production was calculated from the rate of heat storage in the body and clothing. Least-squares best fit equations for oxygen consumption and heat production found were to be and where G is percent grade. Approximations show that (downhill)=0.5 (uphill), (downhill)=0.67 (uphill), and muscular efficiency ? (downhill)=?2? (uphill).

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


Fuzzy development of Mean and Range control charts using statistical properties different representative values This paper develops Mean and Range control charts in fuzzy environment using different transformation methods. It is assumed that the observations of each sample are fuzzy random variables, which have triangular membership functions. After calculating fuzzy mean and fuzzy range of each sample using fuzzy arithmetic, their representative values are calculated exploiting the transformation methods. Then, using statistical properties of the obtained representative values and basic structure of Shewhart control charts, new Mean and Range control charts are constructed to monitor the process mean and variation. After that, the power of control charts constructed based on different transformation methods are examined applying average run length (ARL) criterion. According to this criterion, it is concluded that, contrary to the previous claim, these different transformation methods lead to mean and rang control charts with various performances. Moreover, it is represented that the value of alpha - level has significant influence on the performance of obtained control charts. Finally, it is derived that incorporating fuzziness into observations results in less powerful control charts.

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

mean and range control charts
transformation methods
arl criterion


converting a swap-based system to do paging in an architecture lacking page-referenced bits This paper discusses the modifications made to the UNIX operating system for the VAX-11/780 to convert it from a swap-based segmented system to a paging-based virtual memory system. Of particular interest is that the host machine architecture does not include page-referenced bits. We discuss considerations in the design of page-replacement and load-control policies for such an architecture, and outline current work in modeling the policies employed by the system. We describe our experience with the chosen algorithms based on benchmark-driven studies and production system use.

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

paging
use
architecture
memory system
design
operating system
experience
paper

product policy systems benchmark algorithm model virtualization control


PSEUDORANDOM BITS FOR POLYNOMIALS We present a new approach to constructing pseudorandom generators that fool low-degree polynomials over finite fields, based on the Gowers norm. Using this approach, we obtain the following main constructions of explicitly computable generators G : F-s -> F-n that fool polynomials over a finite field F: 1. a generator that fools degree-2 (i.e., quadratic) polynomials to within error 1/n, with seed length s = O(log n), 2. a generator that fools degree-3 (i.e., cubic) polynomials to within error epsilon, with seed length s = O(log(|F|) n) + f(epsilon, F), where f depends only on epsilon and F (not on n), 3. assuming the "inverse conjecture for the Gowers norm," for every d a generator that fools degree-d polynomials to within error epsilon, with seed length s = O(d . log(|F|) n) + f(d, epsilon, F), where f depends only on d, epsilon, and F (not on n). We stress that the results in (1) and (2) are unconditional, i.e., do not rely on any unproven assumption. Moreover, the results in (3) rely on a special case of the conjecture which may be easier to prove. Our generator for degree-d polynomials is the componentwise sum of d generators for degree-1 polynomials (on independent seeds). Prior to our work, generators with logarithmic seed length were only known for degree-1 (i.e., linear) polynomials [J. Naor and M. Naor, SIAM J. Comput., 22 (1993), pp. 838-856]. In fact, over small fields such as F-2 = {0, 1}, our results constitute the first progress on these problems since the long-standing generator by Luby, Velickovic, and Wigderson [Deterministic approximate counting of depth-2 circuits, in Proceedings of the 2nd Israeli Symposium on Theoretical Computer Science (ISTCS), 1993, pp. 18-24], whose seed length is much bigger: s = exp (Omega (root log n)), even for the case of degree-2 polynomials over F-2.

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 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

pseudorandom generator
polynomial
degree
bias


Resource-bounded paraconsistent inference In this paper, a new framework for reasoning from inconsistent propositional belief bases is presented. A family of resource-bounded paraconsistent inference relations is introduced. Such inference relations are based on S-3 entailment, an inference relation logically weaker than the classical one and parametrized by a set S of propositional variables. The computational complexity of our relations is identified, and their logical properties are analyzed. Among the strong features of our framework is the fact that tractability is ensured each time |S| is bounded and a limited amount of knowledge is taken into account within the belief base. Furthermore, binary connectives. boolean AND.boolean OR behave in a classical manner. Finally, our framework is general enough to encompass several paraconsistent multi-valued logics (including S-3, J(3) and its restrictions), the standard coherence-based approach to inconsistency handling ( based on the selection of consistent subbases) and some signed systems for paraconsistent reasoning as specific cases.

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


A vorticity based aeroacoustic prediction for the noise emission of a low-speed turbulent internal flow Turbulent internal flows are known to generate intense noise as, well as surface pressure fluctuations. Numerically predicting the noise emission near the prescribed boundaries requires that the sound-generating turbulent flow be adequately represented and described. The k-epsilon method provides a promising tool for obtaining the unsteady characteristics of a realistic turbulent flow interacting with a rectangular flat plate undergoing "ground effect". The far-field acoustic calculation is facilitated by the Kambe model (from Lighthill's theory) and an original post-processor has been developed to determine the far-field spectra and the source term characteristics. In pre-processed turbulent confined flows inside a rectangular enclosure, computations using the k-epsilon method, coupled with a convenient post-processor, is used to predict noise radiation over a wide range of frequencies and geometrical configurations. The portability and effectiveness of the present method, however, start to be less evident when the turbulent flow has very chaotic internal features; these suggest the need for a wider computational aeroacoustic domain and a new procedure suitable for the turbulent flow representation. (C) 2003 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 O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O


Fitting mixtures of von Mises distributions: a case study involving sudden infant death syndrome Sudden infant death syndrome (SIDS) exhibits a seasonal pattern with a winter peak. This pattern is not symmetric. It rises rapidly to a winter peak before falling more slowly to a dip in the summer. It has been suggested that the relatively flat peak may be due to the presence of more than one population, where each population corresponds to a different cause of SIDS. Various models based on the von Mises distribution are fitted to monthly data for England, Wales, Scotland and Northern Ireland for the years 19831998, including a single von Mises distribution, a mixture of a von Mises and a uniform distribution and a mixture of two von Mises distributions. There are a number of ways of fitting such models (Fisher, 1993; Spurr and Koutbeiy, 1991). Various computational problems arise with the fitting procedures. Attempts to tackle these problems for the SIDS data are discussed. A bootstrap likelihood ratio approach (Polymenis and Titterington, 1998) is used to assess how many components are required in the model. Its properties are investigated by simulation. The improvement in fit of two components compared to one is not significant in most years, and hence there is little evidence of two populations in the seasonality of SIDS. In most years, it was also impossible to fit a mixture of von Mises and uniform components, with a single von Mises distribution being sufficient.

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


Optimization design of biorthogonal filter banks for image compression In this paper, we present a new approach for designing filter banks for image compression. This approach has two major components: optimization and generalization. In the optimization phase, we formulate the design problem as a nonlinear optimization problem whose objective consists of both the performance metrics of the image coder, such as the peak signal-to-noise ratio (PSNR), and those of individual filters. Filter banks are optimized in the optimization phase based on a set of training images. In the generalization phase, the filter bank that can be generalized to other images is selected from the candidates obtained in the optimization phase to be the final result. The filter bank selected should perform well not only on the training examples used in the design process but also on test cases not seen. In contrast to existing methods that design filter banks independently from the other operations in an image compression algorithm, our approach allows us to find filter banks that work best in a specific image compression algorithm for a certain class of images. In system prototype development, we adopt the agent-based approach to achieve better modularity, portability, and scalability. Agents in the multi-agent system are specialized in performing problem formulation, image compression, optimization, and generalization. In the experiments, we show that on a set of benchmark images our approach has found filter banks that perform better than the existing filter banks in different image compression algorithms and at different compression ratios.

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

nonlinear optimization
generalization
image compression


Design of two step deterministic interleaver for turbo codes ? ?? The performance and design of a deterministic interleaver for short frame turbo codes is considered in this paper. The main characteristic of this class of deterministic interleaver is that their algebraic design selects the best permutation generator such that the points in smaller subsets of the interleaved output are uniformly spread over the entire range of the information data frame. It is observed that the interleaver designed in this manner improves the minimum distance of first few spectral lines of minimum distance spectrum. Finally we introduce a circular shift in the permutation function to reduce the correlation between the parity bits corresponding to the original and interleaved data frames to improve the decoding capability of MAP decoder. The design is focused on combining good permutations with de-correlation property. Our solution to design a deterministic interleaver outperforms the semi-random interleavers and the deterministic interleavers reported in the literature.

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

interleavers
minimum distance
turbo codes

parallel concatenated convolutional codes


Effects of Intracellular Calcium on Cell Survival and the MAPK Pathway in a Human Hormone-Dependent Leukemia Cell Line (TF-1) Changes in the cytoplasmic calcium concentration ([Ca2+]i) regulate a wide variety of cellular processes. Here we demonstrate that increased [Ca2+]i was able to induce hormone-independent survival and proliferation, as well as to evoke apoptosis in human myelo-erythroid GM-CSF/IL-3 dependent leukemia cells (TF-1). Cellular responses induced by elevated [Ca2+]i depended on the duration and amplitude of the calcium-signal. Moderate or high, but transient, elevation of [Ca2+]i caused a transient, biphasic activation of ERK1/2 and protected cells from hormone withdrawal-induced apoptosis.1 In contrast, high and long-lasting elevation of [Ca2+]i led to sustained activation of the ERK1/2 kinases and apoptosis of TF-1 cells. Our data suggest that a time-dependent action of the MAPK pathway works as a decision-point between cell proliferation and apoptosis.

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


Mutually unbiased bases and orthogonal decompositions of lie algebras We establish a connection between the problem of constructing maximal collections of mutually unbiased bases (MUBs) and an open problem in the theory of Lie algebras. More precisely, we show that a collection of mu MUBs in (n) gives rise to a collection of mu Cartan subalgebras of the special linear Lie algebra sl(n)() that are pail-wise orthogonal with respect to the Killing form, where = or =. In particular, a complete collection of MUBs in (n) gives rise to a so-called orthogonal decomposition (OD) of sl(n)(). The converse holds if the Cartan subalgebras in the OD are also dagger-closed; i.e., closed under the adjoint operation. In this case, the Cartan subalgebras have unitary bases, and the above correspondence becomes equivalent to a result of [2] relating collections of MUBs to collections of maximal commuting classes of unitary error bases, i.e., orthogonal unitary matrices. This connection implies that for n <= 5 an essentially unique complete collection of MUBs exists. We define monomial MUBs, a class of which all known MUB constructions are members, and use the above connection to show that for n = 6 there are at most three monomial MUBs.

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

special linear lie algebra
cartan subalgebras

quantum information processing
quantum computing


Multi-script bibliographic database: an Indian perspective In this Internet era, when everything is going on the Web, character encoding becomes an issue for developers and facilitators. This matter also concerns India, as a country with rich diversity in languages, cultures, customs and religions, which are stored in print media as manuscripts, monographs, pamphlet, tamra-patras (copper plates), palm leaves etc. Library and information networks in India hold the responsibility to digitise all those valuable resources stored in print media and make them accessible to users through the Web. However, due to technology limitations, so far it has not been practical to do so. This paper tries to explain the limitations and problems being faced in this regard, highlights the issues involved with multi-script database creation and the required state-of-the-art technology. Finally, Unicode is considered as a solution as it is a Universal Character Set for character encoding.

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


Dynamic fast issue (DFI) mechanism for dynamic scheduled processors Superscalar processors can achieve increased performance by issuing instructions Out-of-Order (OoO) from the original instruction stream. Implementing an OoO instruction scheme requires a hardware mechanism to prevent incorrectly executed instructions from updating registers values, In addition, performance decreases if data dependencies, a branch or a trap among instructions appears. To this end ww propose a new mechanism named Dynamic Fast issue (DFI) mechanism to issue instructions ill all OoO fashion to multiple parallel functional units without considerable hardware complexity. The above system, which will be implemented in our Superscalar Functional Assignments Register Microprocessor (FARM) [1], solves data dependencies, supports precise interrupt and branch prediction, which are the main problems associated with the dynamic scheduling of instructions ill superscalar machines, Results are written only once, Write-once, directly; into the register file (RF). To ensure that results are written in order in their appropriate output registers, a record of instruction order and state is maintained by a status buffer (STB). A 64 entries integrated register file is implemented to hold both renamed and logical registers. To recover the processor state from an interrupt or a branch miss-prediction, a status buffer (STB) and a recovery list table (RLT) are implemented. Novel aspects of the above system architecture as well as the principle underlying: this process and the constraints that must be met is presented, Performance evaluation results are performed through full-pipelined-level architectural simulator and SPECint95 benchmark programs.

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

write-once
register renaming
out-of-order


Optimization of heat-transfer rate into time-periodic two-dimensional Stokes flows The periodic boundary displacement protocol leading to the optimum wall-to-fluid heat-transfer rate, or to the most efficient mixing rate, in 2-D annular Stokes flows is determined by calculating the steady periodic velocity and temperature fields. To obtain the steady periodic state one usually solves the dynamical system obtained after the spatial coordinates have been discretized. Here, we calculate the steady periodic state using an implicit method based on the discretization of the time coordinate over a period and the asymptotic regime is enforced by the periodicity condition in the computed temperature field. The obtained system of equations is solved using a Newton-type iterative algorithm with invariant Jacobian. At each iteration step, the sparse linearized system is solved using a multi-grid algebraic technique of rapid convergence. From a computational point of view and for the problem considered here, this method is an order of magnitude faster than the one based on a spatial discretization. Copyright (c) 2006 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 B I I O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

chaotic advection
lagrangian turbulence
periodic modulation
optimization of mixing rate
heat transfer rate


A Customized Framework to Recompress Massive Internet Images Recently, device storage capacity and transmission bandwidth requirements are facing a heavy burden on account of massive internet images. Generally, to improve user experience and save costs as much as possible, a lot of internet applications always focus on how to achieve appropriate image recompression. In this paper, we propose a novel framework to efficiently customize image recompression according to a variety of applications. First of all, we evaluate the input image's compression level and predict an initial compression level which is very close to the final output of our system using a prior learnt from massive images. Then, we iteratively recompress the input image to different levels and measure the perceptual similarity between the input image and the new result by a block-based coding quality method. According to the output of the quality assessment method, we can update the target compression level, or switch to the subjective evaluation, or return the final recompression result in our system pipeline control. We organize subjective evaluations based on different applications and obtain corresponding assessment report. At last, based on the assessment report, we set up a series of appropriate parameters for customizing image recompression. Moreover, our new framework has been successfully applied to many commercial applications, such as web portals, e-commerce, online game, and so on.

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

massive internet image
image quality assessment


Motion planning for maintaining landmarks visibility with a differential drive robot Collision-free paths for DDRs keeping landmarks visible during motion are planned. Convergence proofs and complexity results are given for the recursive approach. A generalization was proposed to maintain in sight at least one landmark among many. Simulation examples under uncertain environments support the approach pertinence. Real experiments were done with a Pioneer robot.

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


Dynamic modeling of multi-link flexible robotic manipulators This paper presents a linearized dynamic model for multi-link planar flexible manipulators which can include an arbitrary number of flexible links. The elastic deformation of each link is modeled by using the assumed-mode method. Flexible links are treated as EulerBernoulli beams and the rotary inertia and shear deformation are thus neglected. The Lagrange approach is adopted to establish equations of motion for the total robotic manipulator system. The motion of each link is decomposed as the nonlinear gross rigid body motion upon which small elastic deformations are superimposed. The rigid-body motion and elastic deformations are decoupled by linearizing the equations of motion around the rigid-body reference trajectory. The proposed method can be used in both dynamic simulation and controller design. Numerical simulations of two-link flexible robotic manipulators are included to verify the proposed method.

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


table lens as a tool for making sense of data The Table Lens is a visualization for searching for patterns and outliers in multivariate datasets. It supports a lightweight form of exploratory data analysis (EDA) by integrating a familiar organization, the table, with graphical representations and a small set of direct manipulation operators. We examine the EDA process as a special case of a generic process, which we call sensemaking . Using a GOMS methodology, we characterize a few central EDA tasks and compare performance of the Table Lens and one of the best of the more traditional graphical tools for EDA i.e. Splus. This analysis reveals that Table Lens is more or less on par with the power of Splus, while requiring the use of fewer specialized graphical representations. It essentially combines the graphical power of Splus with the direct manipulation and generic properties of spreadsheets and relational database front ends. We also propose a number of design refinements that are suggested by our task characterizations and analyses.

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

evaluation
database visualization
multivariate visualization
information visualization


bringing the data mart into the curriculum The development and deployment of data warehouses have become critical activities in strategic planning and decision-making. Computer and information science students should have an early hands-on exposure to the theoretical and practical aspects of this complex technology. This paper describes the first steps in an ambitious program for bringing the data warehouse into the curriculum. With the support of a NSF-ILI grant, two teams of senior students designed and developed a large-scale data repository on an Oracle platform as part of their capstone projects. This paper reports on the early phase of that process during which students established a data mart with drill-down and advanced data visualization capabilities. The impact of the project on current and future activities in the lab and in the classroom is discussed.

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 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

decision support system
oracle database
information science curriculum


Declarative semantics for active rules In this paper we analyze declarative deterministic and non-deterministic semantics for active rules. In particular, we consider several (partial) stable model semantics, previously defined for deductive rules, such as well-founded, max deterministic, unique total stable model, total stable model and maximal stable model semantics. The semantics of an active program is given by first rewriting it into a deductive program AP, then computing a model M defining the declarative semantics of LP and, finally, applying 'consistent' updates contained in M to the source database. The framework we propose permits a natural integration of deductive and active rules and can also be applied to queries with function symbols or to queries over infinite databases.

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

active databases
deductive databases
stable models


The influence of QoS routing on the achievable capacity in TDMA based Ad hoc wireless networks The issue of providing Quality of Service (QoS) guarantees in an Ad hoc wireless network is a very challenging problem. In this paper, we make the following contributions: (i) analytically derive bounds for the end-to-end call acceptance rate using existing queueing theory methods, (ii) study the impact of the routing scheme on the end-to-end call acceptance rate, and (iii) propose a differentiated services scheme for deterministically providing QoS guarantees. Unlike the existing studies which analyze the transport capacity, we focus on the end-to-end call acceptance. The framework that we assume is that of a TDMA based Ad hoc wireless network. The routing scheme employed influences the end-to-end call acceptance of the network. The metrics that we consider are the call acceptance probability and the system saturation probability (i.e., the probability that the network is in a state in which every new call is rejected). We derive general bounds on the call acceptance and the system saturation for the case of differentiated-classes of users in the network. These bounds indicate the number of calls of the highest priority class that can be admitted into the network. Simulation studies were carried out to study the effect of load, hopcount, and the influence of the routing protocol on the call acceptance. The increase in the call acceptance rate with the introduction of load-balancing highlights the importance of load-balancing in enhancing the system performance. From these studies, we arrive at the following results: (i) load-balancing leads to significant improvement in the end-to-end call acceptance rate, and is an important factor in attaining the maximum end-to-end call acceptance rate in a given network and (ii) it is indeed possible to provide deterministic QoS guarantees for a designated set of nodes which are characterized by deterministic guarantee limit.

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

ad hoc wireless networks
qos routing
tdma
call acceptance probability


Convergence of differential entropies Calculation of the differential entropy of the limiting density of a sequence of probability density functions (pdfs) is an interesting mathematical problem and is important in asymptotic analysis of communication systems. In such cases, it would be of interest to know if the limit of the differential entropies H-n, corresponding to the sequence of pdfs f(n), is equal to the differential entropy H, of the limiting pdf f. In this correspondence, we establish sufficient conditions under which H-n --> H.

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


interactionist ai and the promise of ubicomp, or, how to put your box in the world without putting the world in your box In many ways, the central problem of ubiquitous computing -- how computational systems can make sense of and respond sensibly to a complex, dynamic environment laden with human meaning -- is identical to that of Artificial Intelligence (AI). Indeed, some of the central challenges that ubicomp currently faces in moving from prototypes that work in restricted environments to the complexity of real-world environments -- e.g. difficulties in scalability, integration, and fully formalizing context -- echo some of the major issues that have challenged AI researchers over the history of their field. In this paper, we explore a key moment in AI's history where researchers grappled directly with these issues, resulting in a variety of novel technical solutions within AI. We critically reflect on six strategies from this history to suggest technical solutions for how to approach the challenge of building real-world, usable solutions in ubicomp today.

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


Combining knowledge with many-valued logics During the process of knowledge acquisition from different experts it is usual that contradictions occur. Therefore strategies are needed for dealing with divergent statements and conflicts. We provide a formal framework to represent, process and combine distributed knowledge. The representation formalism is many-valued logic, which is a widely accepted method for expressing uncertainty, vagueness, contradictions and lack of information. Combining knowledge as proposed here makes use of the bilattice approach, which turns out to be very flexible and suggestive in the context of combining divergent information. We give some guidelines for choosing truth value spaces, assigning truth values and defining global operators to encode integration strategies.

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

semantic conflicts
distributed knowledge acquisition
signed logics
bilattices


Transmission system repair and restoration This paper studies the use of mathematical programming for the repair and restoration of a transmission system after a significant disruption (e.g., a natural disaster). Such blackouts may last several days and have significant impact on human and economic welfare. The transmission system repair and restoration problem (TSRRP) consists in dispatching crews to repair damaged electrical components in order to minimize the size of the blackout. The TSRRP can be modeled as a large-scale mixed nonlinear, nonconvex program, including both routing components and the nonlinear steady-state power flow equations. To tackle its daunting computational complexity, this paper proposes a 2-stage approach, decoupling the restoration and repair aspects. The first step is a restoration ordering problem, a mixed nonlinear, nonconvex program which is approximated by a mixed integer program. The approximation does not use the traditional DC power flow approximation which is plagued by convergence issues and inoperable dispatches; rather, it uses the recent LPAC approximation that captures reactive power and voltage magnitudes. The second stage is a pickup and repair routing problem which is solved using a constraint-programming model, large neighborhood search, and a randomized adaptive decomposition. Experimental results on benchmarks based on the US electrical infrastructures and state-of-the-art damage scenarios indicate that the 2-stage approach provides significant improvements over the best practice in the field.

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


Pricing strategies for differentiated services content delivery networks In order to reduce the user latency, the web sites disseminate some of their information to surrogate caches located closer to the users. We discuss a simple differentiated service type architecture for content delivery networks. A pricing scheme is next proposed to complement this architecture and provide fair service to the subscribed publishers. Then, we show that the suggested pricing scheme is also the optimal (revenue maximizing) pricing scheme for a monopolistic surrogate. We investigate the performance of the pricing scheme in a duopoly and show that under certain conditions the competition results in peering of the surrogates. Finally, we suggest methods to determine the optimal number of service classes offered to the users. (c) 2005 Elsevier B.V. All rights reserved.

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

game theoretical modeling of communication networks

internet service classes under competition


A note on the convergence theorem of generalized fuzzy integrals In the note, we prove a new convergence theorem of generalized fuzzy integrals for the decreasing sequence of nonnegative measurable functions, which improves and generalizes the corresponding results of Wu et al, (Fuzzy Sets and Systems 70 (1995) 75), Wang and Klir (Fuzzy Measure Theory, Plenum, New York, 1992). (C) 2002 Elsevier Science B.V. All rights reserved.

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

generalized fuzzy integral
(s) fuzzy integral
(n) fuzzy integral


Human-competitive evolution of quantum computing artefacts by genetic programming We show how Genetic Programming (GP) can be used to evolve useful quantum computing artefacts of increasing sophistication and usefulness: firstly specific quantum circuits, then quantum programs, and finally system-independent quantum algorithms. We conclude the paper by presenting a human-competitive Quantum Fourier Transform (QFT) algorithm evolved by GP.

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


Mobility management for m-commerce requests in wireless cellular networks Increasing number of sophisticated services provided by the current wireless communication systems have caused a significant transition from E-commerce to M-commerce. Enterprises have provided considerable new opportunities to promote their businesses accessible from small mobile devices such as personal digital assistant (PDA) or mobiles phones. These facilities are envisioned as the most convenient way of using M-commerce. Using such services from mobile phones or PDAs equipped with GSM/GPRS involve effective mobility management mechanisms in cellular networks-a popular architecture for wireless networks. Success of such systems will largely depend on the reliable connection for the roaming users. Consequently, Quality of Service (QoS) provision is one of the most challenging issues in the heterogeneous wireless network-based m-commerce systems. Such m-commerce systems enable users to roam between different wireless networks operators and geographical areas while providing interactive broadband services and seamless connectivity. This paper presents an analytical framework to model scarce channels in any cell for maximizing channel utilization and efficient handling of handover requests. Typical numerical experiments are presented to validate the analytical solution against simulation to study the effect of bursty traffic upon the performance of the cell in any cellular networks.

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

m-commerce
performance evaluation
wireless handover mechanism


Chip-Package Interaction in 3D stacked IC packages using Finite Element Modelling Analytical modelling, FEM simulations and 4 point bending for BEOL strength analysis. Reduced low-k stiffness results in exponential growth of stress in Cu vias. Keep-out-zones around copper through silicon vias are defined.

O O O B I I O O B I I 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

beol
3d stacked ic
finite element modelling

chip package interaction
thermo-mechanical stress


supervised semantic indexing In this article we propose Supervised Semantic Indexing (SSI), an algorithm that is trained on (query, document) pairs of text documents to predict the quality of their match. Like Latent Semantic Indexing (LSI), our models take account of correlations between words (synonymy, polysemy). However, unlike LSI our models are trained with a supervised signal directly on the ranking task of interest, which we argue is the reason for our superior results. As the query and target texts are modeled separately, our approach is easily generalized to different retrieval tasks, such as online advertising placement. Dealing with models on all pairs of words features is computationally challenging. We propose several improvements to our basic model for addressing this issue, including low rank (but diagonal preserving) representations, and correlated feature hashing (CFH). We provide an empirical study of all these methods on retrieval tasks based on Wikipedia documents as well as an Internet advertisement task. We obtain state-of-the-art performance while providing realistically scalable methods.

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 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


User acceptance and corporate intranet quality: An evaluation with iQual We developed a model for intranet quality and acceptance; it was applied to data collected by the sales and marketing division of an international manufacturing company obtained via a Web survey (n=131) and tested using partial least squares path modeling. A strong explanation of behavioral intentions was revealed. The results showed that intranet quality (composed of usability, design, and information quality) was a significant factor in determining behavioral intention to use, although it was less important than perceived usefulness and social influence. Comments collected from respondents were analyzed via content analysis and further used to illustrate the findings.

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


Oscillation-based test in bandpass oversampled A/D converters This paper extends a study performed by the authors in previous papers dealing with the OBT approach applied to low-pass modulators Microelectron. J. 33/10 (2002) 799, showing herein the specific features associated to the bandpass case. A practical feedback strategy will be proposed in order to built an effective oscillator, which can be valuable for testing purposes. Critical points of the proposed OBT solution will be considered in order to establish useful guidelines to apply this test approach to generic bandpass ?? modulators.

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

mixed-signal design
design for test
oscillation-based test
test of ?? modulators


Analysis and optimization of dynamically loaded porous metal sliding bearings under conditions of elastohydrodynamic lubrication Purpose - This paper aims to develop a simulating model of a journal porous metal bearing under elastohydrodynamic conditions and combined (radial, friction and thermal) load distribution and to carry out structural optimization. Design/methodology/approach - The structure analysis is carried out for each kind of load separately and for the combined load distribution of the bearing, where a dynamically loaded porous metal bearing is simulated. This simulating model is developed by finite elements method using the structure analysis module of the CATIA V5 software. Further, a parameter optimization of a porous metal bearing is presented considering the elastic deformations of the bearing shell. Findings - It is revealed that the bearing, even at points with maximum displacements, could not reach the mounting clearance value during its operational life. Relatively small bearing dimensions produce very high values of eigenfrequency response (over 150 kHz) and common dynamic loads met in all sorts of sliding bearing are not dangerous for bearing damage compared with static loads. In the stage of structural optimization based on the correlation between stress and geometric bearing parameters like wall thickness and outer diameter, the influence of finite element dimension on calculated results can be also analyzed and a proper choice of the latter is achieved. Research limitations/implications - The present porous bearing optimization model with the aid of CATIA V5 module for optimum design uses only single objective optimization. For a complete optimum design a multi-objective optimization has to be carried out. Practical implications - The analysis under dynamic load conditions proved that relatively small dimensions of bearing commonly used in micro technique and precision mechanics result in extended safe and reliable operation. Originality/value - This paper provides a methodology for bearing stress and deformation analysis in the elastic range and on the basis of this analysis it is possible to develop an optimization model for porous bearings offering help to designers for the selection of optimal bearing dimensions considering the bearing load caused by dynamic radial force, friction and temperature variation.

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

porous materials
structural analysis
elastic analysis
finite element analysis
optimization techniques


An Adaptive Thresholding algorithm of field leaf image ? The CANNY and OTSU operators to choose their thresholds adaptively. Morphological methods and logical operations eliminate strong interference. The traverse ensures the result edge is accurate, complete and optimal. The adjustment of the algorithm flow fits different images contrast situations.

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

image processing
jujube leaf
segmentation algorithms
mapping function
online image


Orientation Imaging Microscopy With Optimized Convergence Angle Using CBED Patterns in TEMs Grain size statistics, texture, and grain boundary distribution are microstructural characteristics that greatly influence materials properties. These characteristics can be derived from an orientation map obtained using orientation imaging microscopy (OIM) techniques. The OIM techniques are generally performed using a transmission electron microscopy (TEM) for nanomaterials. Although some of these techniques have limited applicability in certain situations, others have limited availability because of external hardware required. In this paper, an automated method to generate orientation maps using convergence beam electron diffraction patterns obtained in a conventional TEM setup is presented. This method is based upon dynamical diffraction theory that describes electron diffraction more accurately as compared with kinematical theory used by several existing OIM techniques. In addition, the method of this paper uses wide angle convergent beam electron diffraction for performing OIM. It is shown in this paper that the use of the wide angle convergent electron beam provides additional information that is not available otherwise. Together, the presented method exploits the additional information and combines it with the calculations from the dynamical theory to provide accurate orientation maps in a conventional TEM setup. The automated method of this paper is applied to a platinum thin film sample. The presented method correctly identified the texture preference in the sample.

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

convergent beam electron diffraction (cbed)


Instantly indexed multimedia databases of real world events We introduce a new paradigm for real-time conversion of a real world event into a rich multimedia database by processing data from multiple sensors observing the event. Real-time analysis of the sensor data, tightly coupled with domain knowledge, results in instant indexing of multimedia data at capture time. This yields semantic information to answer complex queries about the content and the ability to extract portions of data that correspond to complex actions performed in the real world. The power of such an instantly indexed multimedia database system, in content-based retrieval of multimedia data or in semantic analysis and visualization of the data, far exceeds that of systems that index multimedia data only after it is produced. We present LucentVision, an instantly indexed multimedia database system developed for the sport of tennis. This system analyzes video from multiple cameras in real time and captures the activity of the players and the ball in the form of motion trajectories. The system stores these trajectories in a database along with video, three-dimensional (3-D) models of the environment, scores, and other domain-specific information. LucentVision has been used to enhance live television and Internet broadcasts with game analysis and virtual replays in more than 250 international tennis matches.

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

broadcast
content-based retrieval
tracking
vision
visual data mining


A computational diffusion MRI and parametric dictionary learning framework for modeling the diffusion signal and its features We develop an parametric dictionary learning algorithm to recover the dMRI signal with a reduced number of measurements. We propose a computational framework to model continuous dMRI signals and analytically recover the EAP, the ODF. This approach indicates a much better accuracy in terms of reconstruction error compared to state-of-the-art approaches.

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

sparse reconstruction
orientation distribution function
ensemble average propagator


a novel recommender system fusing the opinions from experts and ordinary people In this paper, we propose a novel recommendation algorithm fusing the opinions from experts and ordinary people. Instead of regarding one's judgement capability as his/her expertise, we present a new definition which measures the amount of the recommendable items one know in a certain area. When computing the expertise, we consider both the average value and the accumulative value, and introduce a free parameter ? to tune between these two values. To evaluate the proposed algorithm, simulations are run on the Moviepilot dataset, and the results demonstrate that our algorithm outperforms the conventional collaborative filtering algorithm.

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


A study of enhanced structured web-based discussion in a foreign language learning class This experimental study aimed to investigate the effect of enhanced structured web discussion on EFL students' language production. This effect was measured by the number of T units and by students' use of the cognitive skills identified by Hunt (1965). A total of 27 college students participated in this study. The participants were randomly assigned to one of the three groups: the control group, the affective enhancement group and the cognitive enhancement group. Although the students in these groups received different treatment during the study, all of the students received the same instructional materials from the same instructor. The study was divided into three stages, and students' discussion messages from the first and the last stage were collected and analysed. An ANOVA test was used to compare the mean differences among the three groups. The results showed that cognitive enhancements were beneficial both to students' language production and their application of cognitive skills. Although the results from the affective enhancement group were not as significant as those from the cognitive enhancement group, the students from the affective enhancement group also experienced improvement in both language production and the use of cognitive skills. (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 O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

computer-mediated communication
improving classroom teaching
interactive learning environment
pedagogical issues
teaching/learning strategies


Grammar systems versus membrane computing: The case of CD grammar systems In this paper we discuss some relationships between grammar systems and P systems (membrane systems), two areas of computer science dealing with distributed computing models, but with different motivations and different types of basic ingredients. We extend one of the most important communication protocols of cooperating distributed (CD) grammar systems, the so-called t-derivation mode, to P systems with string-objects: if no rule can be applied to a string in a region of a P system, then the string is moved to a neighbouring region, depending on the communication mode either in exactly one direction (in or out) or in both directions. We describe the computational power of the obtained classes of P systems in comparison with families of languages generated by grammars in the Chomsky hierarchy or with CD grammar systems and formulate several problems for future research.

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 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 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


Decentralized resource management for a distributed continuous media server Distributed continuous media server (DCMS) architectures are proposed to minimize the communication-storage cost for those continuous media applications that serve a large number of geographically distributed clients. Typically, a DCMS is designed as a pure hierarchy (tree) of centralized continuous media servers. In an earlier work, we proposed a redundant hierarchical topology for DCMS networks, termed RedHi, which can potentially result in higher utilization and better reliability over pure hierarchy. In this paper, we focus on the design of a resource management system for RedHi that can exploit the resources of its DCMS network to achieve these performance objectives. Our proposed resource management system is based on a fully decentralized approach to achieve optimal scalability and robustness. In general, the major drawback of a fully decentralized design is the increase in latency time and communication overhead to locate the requested object. However, as compared to the typically long duration and high resource/bandwidth requirements of continuous media objects, the extra latency and overhead of a decentralized resource management approach become negligible. Moreover, our resource management system collapses three management tasks, 1) object location, 2) path selection, and 3) resource reservation, into one fully decentralized object delivery mechanism, reducing the latency even further. In sum, decentralization of the resource management satisfies our scalability and robustness objectives, whereas collapsing the management tasks helps alleviate the latency and overhead constraints. To achieve a high resource utilization, the object delivery scheme uses our proposed cost function, as well as various object location and resource reservation policies to select and allocate the best streaming path to serve each request. The object delivery scheme is designed as an application layer resource management middleware for the DCMS architecture to be independent of the underlying telecommunication infrastructure. Our experiments show that our resource management system is successful in realization of the higher resource utilization for the DCMS networks with the RedHi topology.

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

distributed continuous media servers
distributed multimedia systems
content delivery networks
distributed information systems
video-on-demand


Predicting Collaboration Technology Use: Integrating Technology Adoption and Collaboration Research The paper presents a model integrating theories from collaboration research (i.e., social presence theory, channel expansion theory, and the task closure model) with a recent theory from technology adoption research (i.e., unified theory of acceptance and use of technology, abbreviated to UTAUT) to explain the adoption and use of collaboration technology. We theorize that collaboration technology characteristics, individual and group characteristics, task characteristics, and situational characteristics are predictors of performance expectancy, effort expectancy, social influence, and facilitating conditions in UTAUT. We further theorize that the UTAUT constructs, in concert with gender, age, and experience, predict intention to use a collaboration technology, which in turn predicts use. We conducted two field studies in Finland among (1) 349 short message service (SMS) users and (2) 447 employees who were potential users of a new collaboration technology in an organization. Our model was supported in both studies. The current work contributes to research by developing and testing a technology-specific model of adoption in the collaboration context.

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

collaboration technologies
technology acceptance


Post-decision inference editing of supportive and counterindicative signals among external auditors in a going concern judgment There is evidence that the extent of common judgment biases e.g., hindsight, anchoring and adjustment, representativeness, and confirmatory strategies often is reduced when experts perform job-related tasks as compared to students performing generic tasks or professional tasks for which they lack experience; that specialized judgment heuristics may be used for tasks within an expert's domain, whereas general cognitive heuristics may be used in situations where the individual lacks information and/or expertise. Our focus here is on post-decision inference restructuring/editing; the unconscious revision of what one saw and thought in the pre-decision stage as a result of outcome feedback/lack of feedback. We found that professional auditors, in retrospect, were likely to edit crucial decision making signals, but that the extent of the post-decision editing is a function of the task and the presence/absence of feedback. Professional auditors were provided with relevant financial and non-financial information (based on an actual company), and asked to isolate the most prominent signals (positive and negative) concerning the company's viability. The participants were then asked to give the company either an unmodified (supporting the company's viability) or a going concern (raising questions about the company's survival) audit report, and to rate the importance of key aspects with respect to the chosen alternative. After an intermission, the participants in the experiment group were given information about the actual outcome, whereas the participants in the control group received no feedback. The participants were then asked to replicate their aspect ratings, and to assess the probability that the company actually received a going concern modification/an unmodified audit report. The results indicate that outcome feedback/lack of feedback had an effect on post-decision restructuring of signals. Lack of feedback among professional participants seems to invite greater post-decision adjustments than access to feedback, in particular among participants who chose a going concern report. This relatively less common, more consequential choice, invited drastic post-decision editing of the second and third most supportive aspects, as well as of the three counterindicative aspects. We believe that this kind of post-decision inference editing has less to do with traditional hindsight than with a strengthening predisposition with roots in the pre-decision phase.

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

auditing decisions
post-decision inference editing


Automatic orientation and recognition in highly structured scenes1 The paper discusses the impact of scene and assessment models for videometry. The role of geometric and semantic scene knowledge for 3D-modeling is discussed as well as the impact on the 3D-reconstruction process and the accuracy of results. Three issues are covered: the automation of orientation and calibration procedures, the recognition for 3D-mensuration and automatic 3D-reconstruction. Full automation of calibration and orientation procedures appears to be necessary for enlarging the field of applications also for non-specialists. Explicit geometric information and semantic knowledge about the scene are needed to achieve reliable 3D-descriptions. The focus of achieving highest possible accuracy needs to be embedded into a broader context of scene analysis. Models must be able to reflect the different aggregation layers of composite objects to automatically identify object parts in the image data. Examples are given on the role of projective geometry for automatic calibration, the role of scene knowledge for automatic orientation and on traffic light program for automatic evaluation. They demonstrate the feasibility of tools from computer vision for image metrology.

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

computer vision and photogrammetry
camera orientation
3d-modeling
object- and image models
segmentation


Algorithmic fusion for more robust feature tracking We present a framework for merging the results of independent feature-based motion trackers using a classification based approach. We demonstrate the efficacy of the framework using corner trackers as an example. The major problem with such systems is generating ground truth data for training. We show how synthetic data can be used effectively to overcome this problem. Our combined system performs better in both dropouts and errors than a correspondence tracker, and had less than half the dropouts at the cost of moderate increase in error compared to a relaxation tracker.

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

motion analysis
combining multiple trackers


Statistical characterization of the UWB propagation channel in indoor residential environment This paper presents a statistical characterization of an ultra wideband (UWB) indoor propagation channel based on measurements conducted in various types of high-rise apartments in several cities of Korea. Measurements were carried out in the frequency band of 3-10 GHz. Various communication links were considered including both line-of-sight (LOS) and non-LOS (NLOS) scenarios, which covered within-the-room and room-to-room propagations. The measurement procedure allows us to characterize both the large-scale and the small-scale statistics of the channel. The aim here is to study in more detail the statistical characteristics of the UWB propagation channel and to provide insight for future statistical channel modeling work. Channel characteristics examined include the distance and frequency dependency of path loss, shadowing fading statistics, and multipath temporal-domain parameter statistics such as the mean excess delay, RMS delay spread, and the number of dominant paths. Copyright (c) 2005 John Wiley & Sons, Ltd.

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

channel modeling
indoor propagation
path loss
rms delay spread
shadowing
ultra wideband


a hybrid unsupervised approach for document clustering We propose a hybrid, unsupervised document clustering approach that combines a hierarchical clustering algorithm with Expectation Maximization. We developed several heuristics to automatically select a subset of the clusters generated by the first algorithm as the initial points of the second one. Furthermore, our initialization algorithm generates not only an initial model for the iterative refinement algorithm but also an estimate of the model dimension, thus eliminating another important element of human supervision. We have evaluated the proposed system on five real-world document collections. The results show that our approach generates clustering solutions of higher quality than both its individual components.

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

em initialization
unsupervised clustering


Separation of combustion noise in IC engines under cyclo-non-stationary regime The separation and ranking of combustion and mechanical noise sources is of prime concern for the noise control of internal combustion (IC) engines. Signal processing techniques have been devised recently that can achieve such a separation using the cyclostationary property of IC engine signals. The object of this paper is to extend this framework to the situation where the engine undergoes a transient speed regime, for instance during a run-up. This raises some new and non-trivial questions. First, the assumption of cyclostationarity has to be relaxed and replaced by the vaguer notion of cyclo-non-stationarity. Second and related to the first point the practice of cyclic averaging has to be revisited. Third, the design of the separation filter must explicitly incorporate speed dependence. This paper proposes simple but robust solutions to these issues, with a special effort to make them practicable from an industrial point of view. In particular, the cyclic difference operator is introduced in lieu of cyclic averaging, and speed-dependence is captured by use of a flexible basis of B-splines whose knots density is automatically selected from the data. Successful examples of separation are then demonstrated on actual data measured during an engine run-up.

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

emle empirical maximum likelihood estimator


Cross-validation of bimodal health-related stress assessment This study explores the feasibility of objective and ubiquitous stress assessment. 25 post-traumatic stress disorder patients participated in a controlled storytelling (ST) study and an ecologically valid reliving (RL) study. The two studies were meant to represent an early and a late therapy session, and each consisted of a "happy" and a "stress triggering" part. Two instruments were chosen to assess the stress level of the patients at various point in time during therapy: (i) speech, used as an objective and ubiquitous stress indicator and (ii) the subjective unit of distress (SUD), a clinically validated Likert scale. In total, 13 statistical parameters were derived from each of five speech features: amplitude, zero-crossings, power, high-frequency power, and pitch. To model the emotional state of the patients, 28 parameters were selected from this set by means of a linear regression model and, subsequently, compressed into 11 principal components. The SUD and speech model were cross-validated, using 3 machine learning algorithms. Between 90% (2 SUD levels) and 39% (10 SUD levels) correct classification was achieved. The two sessions could be discriminated in 89% (for ST) and 77% (for RL) of the cases. This report fills a gap between laboratory and clinical studies, and its results emphasize the usefulness of Computer Aided Diagnostics (CAD) for mental health care.

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

post-traumatic stress disorder (ptsd)
computer aided diagnostics (cad)
validity


Efficient algorithms for constructing (1+epsilon,beta)-spanners in the distributed and streaming models For an unweighted undirected graph G = (V, E), and a pair of positive integers alpha >= 1, beta >= 0, a subgraph G' = (V, H), H subset of E, is called an (alpha, beta)-spanner of G if for every pair of vertices u, v is an element of V, dist(G')(u, v) 0, K = 1, 2..., there exists an integer beta = beta(is an element of, K) such that for every n-vertex graph G there exists a (1 + is an element of, beta)-spanner G' with O(n(1+1/K)) edges. An efficient distributed protocol for constructing (1 + is an element of, beta)-spanners was devised in [19]. The running time and the communication complexity of that protocol are O(n(1+rho)) and O(vertical bar E vertical bar n(rho)), respectively, where rho is an additional control parameter of the protocol that affects only the additive term beta. In this paper we devise a protocol with a drastically improved running time (O(n(rho)) as opposed to O(n(1+rho))) for constructing (1 + is an element of, beta)-spanners. Our protocol has the same communication complexity as the protocol of [19], and it constructs spanners with essentially the same properties as the spanners that are constructed by the protocol of [19]. The protocol can be easily extended to a parallel implementation which runs in O(log n + (vertical bar E vertical bar (.) n(rho)logn)/p) time using p processors in the EREW PRAM model. In particular, when the number of processors, p, is at least vertical bar E vertical bar center dot n(rho), the running time of the algorithm is 0 (log n). We also show that our protocol for constructing (1 + is an element of, beta) -spanners can be adapted to the streaming model, and devise a streaming algorithm that uses a constant number of passes and O(n(1+1/K) center dot log n) bits of space for computing all-pairs-almost-shortest-paths of length at most by a multiplicative factor (1 + is an element of) and an additive term of greater than the shortest paths. Our algorithm processes each edge in time O(n(rho)), for an arbitrarily small p > 0. The only previously known algorithm for the problem [23] constructs paths of length K times greater than the shortest paths, has the same space requirements as our algorithm, but requires O(n(1+1/K)) time for processing each edge of the input graph. However, the algorithm of [23] uses just one pass over the input, as opposed to the constant number of passes in our algorithm.(1) We also show that any streaming algorithm for o(n)approximate distance computation requires Omega (n) bits of space.

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APPROXIMATING MINIMUM MAX-STRETCH SPANNING TREES ON UNWEIGHTED GRAPHS Given a graph G and a spanning tree T of G, we say that T is a tree t-spanner of G if the distance between every pair of vertices in T is at most t times their distance in G. The problem of finding a tree t-spanner minimizing t is referred to as the Minimum Max-Stretch spanning Tree (MMST) problem. This paper concerns the MMST problem on unweighted graphs. The problem is known to be NP-hard, and the paper presents an O(log n)-approximation algorithm for it. Furthermore, it is established that unless P = NP, the problem cannot be approximated additively by any o(n) term.

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