Multi-operator wireless mesh networks secured by an all-encompassing security architecture Wireless Mesh Networks (WMNs) consist of a wirelessly connected infrastructure of Mesh Routers (MRs) connected to the Internet via Mesh Gateways. Previous proposals on WMN security mainly focus on mesh networks operated by a single operator and rarely support mobility of Mesh Clients (MCs) with the help of secure roaming and handover procedures. While these approaches protect the communication of MCs against external attackers, they do not take internal attackers into account. In our previous work, we proposed a security architecture for single-operator WMNs, extended this architecture to the multi-operator case to support roaming between operators and secure infrastructure sharing and proposed secure handover procedures within the domain of a single operator. In this paper, we merge the different aspects of our prior proposals together to form a comprehensive security architecture for multi-operator WMNs. Our solution is based on open standards and explicitly addresses internal attackers. In addition, we propose pro-active handover services between different operators and show how dedicated MRs can take over authentication services in time-critical situations such as handover procedures.

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

wireless mesh networks
security
handover


A controlled experiment comparing the maintainability of programs designed with and without design patterns - A replication in a real programming environment Software "design patterns" seek to package proven Solutions to design problems in a form that makes it possible to find, adapt and reuse them. To support the industrial use of design patterns, this research investigates when, and how, using patterns is beneficial, and whether some patterns are more difficult to use than others. This paper describes a replication of an earlier con trolled experiment on design patterns in maintenance. with major extensions. Experimental realism was increased by using a real programming environment instead of pen and paper, and paid professionals from multiple major consultancy companies as Subjects. Measurements of elapsed time and correctness were analyzed using regression models and an estimation method that took into account the correlations present in the raw data. Together with on-line logging of the subjects' work, this made possible a better qualitative understanding of the results. The results indicate quite strongly that some patterns are much easier to understand and use than others. In particular, the Visitor pattern caused much confusion. Conversely, the patterns Observer and, to a certain extent, Decorator were grasped and used intuitively, even by Subjects with little or no knowledge of patterns. The implication is that design patterns are not universally good or bad, but must be used in a way that matches the problem and the people. When approaching a program with documented design patterns, even basic training can improve both the speed and quality of maintenance activities.

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

controlled experiment
design patterns
real programming environment


A neural mass model of place cell activity: theta phase precession, replay and imagination of never experienced paths Recent results on hippocampal place cells show that the replay of behavioral sequences does not simply reflect previously experienced trajectories, but may also occur in the reverse direction, or may even include never experienced paths. In order to elucidate the possible mechanisms at the basis of this phenomenon, we have developed a model of sequence learning. The present model consists of two layers of place cell units. Long-range connections among units implement heteroassociation between the two layers, trained with a temporal Hebb rule. The network was trained assuming that a virtual rat moves within a virtual maze. This training leads to the formation of bidirectional synapses between the two layers, i.e. synapses connecting a neuron both with its previous and subsequent element in the path. Subsequently, two distinct conditions were simulated with the trained network. During an exploratory phase, characterized by a similar consideration to the external environment and to the internal representation, the model simulates the occurrence of theta precession in the forward path and the temporal compression. During an imagination phase, when there is no consideration to the external location, the model produces trains of gamma oscillations, without the presence of a theta rhythm, and simulates the occurrence of both direct and reverse replay, and the imagination of never experienced paths. The new paths are built by combining bunches of previous trajectories. The main mechanisms at the basis of this behavior are explained in detail, and lines for future improvements (e.g., to simulate preplay) are discussed.

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

computational model
sequence memorization
spatial navigation


A multi-functional knowledge based system to learn, apply and consult procedures One of the main challenges facing systems developers is to design systems with the flexibility and adaptability required to satisfy a professional user's needs. This paper presents a novel architecture and a knowledge representation scheme for a multi-functional adaptive system that support professional engineers that work with established procedures. The system achieves its multi-functionality by using a single knowledge representation scheme based on a set of modular networks. The developed representation is exploited by three operators that enable a user to learn, consult different procedures and solve problems. The representation also facilitates the automatic generation of problems and the identification of user errors. The integration of functionalities through a single representation produces a synergy that results in extra-functionality, flexibility and reduces the amount of development effort required. The system adapts to a user by using simple but efficient user modelling techniques that tailor the tutoring information. A rule-based mechanism is used to propose an agenda and a novel rule simplification algorithm is developed to help an expert to develop the rules for proposing the agenda. A prototype was developed and three civil engineering procedures were implemented to evaluate the architecture through scenarios and an empirical evaluation with real engineers.

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


automating test case definition using a domain specific language Effective test cases are critical to the success of a development effort but their creation requires large amounts of critical resources such as domain expertise. This study explores an approach to automating test case definition in the context of applying a model driven approach to the development of a software product line. In this study, test cases are automatically extracted from use cases, which are specified using a domain specific language (DSL). DSLs are easier for domain experts to use than formal specification languages and are more narrowly focused than natural languages making it easier to build tools. The task is further simplified by restricting the DSL to the scope of the software product line under development. The structure of the DSL and proven patterns of test design provide the clues necessary to be able to automatically extract the test cases. A chain of model-driven tools is used to automate the system test process, which begins with a use case model and ends with automatic execution of system tests.

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 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 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

software product line
domain specific language


The robustness of the p-norm algorithms We consider two on-line learning frameworks: binary classification through linear threshold functions and linear regression. We study a family of on-line algorithms, called p-norm algorithms, introduced by Grove, Littlestone and Schuurmans in the context of deterministic binary classification. We show how to adapt these algorithms for use in the regression setting, and prove worst-case bounds on the square loss, using a technique from Kivinen and Warmuth. As pointed out by Grove, et al., these algorithms can be made to approach a version of the classification algorithm Winnow as p goes to infinity; similarly they can be made to approach the corresponding regression algorithm EG in the limit. Winnow and EG are notable for having loss bounds that grow only logarithmically in the dimension of the instance space. Here we describe another way to use the p-norm algorithms to achieve this logarithmic behavior. With the way to use them that we propose, it is less critical than with Winnow and EG to retune the parameters of the algorithm as the learning task changes. Since the correct setting of the parameters depends on characteristics of the learning task that are not typically known a priori by the learner, this gives the p-norm algorithms a desireable robustness. Our elaborations yield various new loss bounds in these on-line settings. Some of these bounds improve or generalize known results. Others are incomparable.

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

on-line learning
learning rate
dual norms
on-line model selection


Nonlinear coherent excitonic solid gates for quantum computation The dipole-dipole interaction among excitons is shown to give rise to an intrinsic nonlinearity, which yields a localized mode in a forbidden band, providing a coherent state far quantum computation. Employing this mode, a quantum XOR (exclusive OR) gate is proposed, A block structure of quantum dot arrays is also proposed, to implement quantum circuits comprising the quantum XOR gates for computation.

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

nonlinear localized excitonic mode
quantum gate
dipole-dipole interaction


Computing highly oscillatory physical optics integral on the polygonal domain by an efficient numerical steepest descent path method ? In this work, the computation of physical optics (PO) type integral with the integrand of quadratic phase and amplitude is studied. First, we apply the numerical steepest descent path (NSDP) method to calculate the highly oscillatory PO integral on the triangular patch. Then, we rigorously extend the proposed NSDP method to analyze the PO integral on polygonal domains. Furthermore, the contributions of critical points on polygonal domains, including the stationary phase point, resonance and vertex points, are comprehensively studied in terms of the NSDP method. Compared to the traditional high frequency asymptotic (HFA) method, when the wave frequency is not very high but in the high frequency regime, the NSDP method has improved the PO integral accuracy by one to two digits. Meanwhile, the computational cost by using the proposed NSDP method is independent of the wave frequency.

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

physical optics
numerical steepest descent path
polygonal domain
critical points

highly oscillatory integral
asymptotic approximation


Induction of Fetal Globin in ?-Thalassemia: Cellular Obstacles and Molecular Progress Abstract: Accelerated apoptosis of erythroid progenitors in ?-thalassemia is a significant barrier to definitive therapy because the beneficial effects of fetal globin-inducing agents on globin chain balance may not be inducible in cells in which programmed cell death is established early. Accordingly, our objectives have been to identify methods to decrease cellular apoptosis and to identify orally tolerable fetal globin gene inducers. A pilot clinical trial was conducted to determine whether combined use of a fetal globin gene inducer (butyrate) and rhu-erythropoietin (EPO), the hematopoietic growth factor that prolongs erythroid cell survival and stimulates erythroid proliferation, would produce additive hematologic responses in any thalassemia subjects. Butyrate and EPO were administered in 10 patients. Novel fetal globin gene inducers that also stimulate erythroid proliferation were evaluated for pharmacokinetic profiles. Patients with ?+-thalassemia had relatively low levels of endogenous EPO ( 60%) and EPO levels (>160 mU/mL), and three-fourths of these subjects responded to the fetal globin gene inducer alone. A few select fetal globin-inducing short-chain fatty acid derivatives that stimulated cell proliferation also had favorable pharmacokinetics. These studies identify a significant subset of thalassemia patients who appear to require exogenous EPO to respond optimally to any HbF inducer, as well as new therapeutic candidates that act on both cellular and molecular pathologies of ?-thalassemia. Both approaches now offer excellent potential for tolerable, definitive treatment of ?-thalassemia.

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

short-chain fatty acid
erythropoietin
fetal hemoglobin
molecular signaling


A unified model between the weighted average and the induced OWA operator We present a new model that uses the weighted average (WA) and the induced ordered weighted averaging (IOWA) operator in the same formulation. We call it the induced ordered weighted averagingweighted average (IOWAWA) operator. We study some of its main properties and we see that it has a lot of particular cases such as the WA and the OWA operator. The main advantage of the IOWAWA operator is that it unifies the IOWA operator with the WA in the same formulation considering the degree of importance that each concept has in the aggregation. We analyze the applicability of this new approach and we see that it is very broad because it can be applied in a wide range of fields such as statistics, economics, decision theory and engineering. Theoretically, we could state that all the previous models and applications based on the WA and the IOWA can be revised and improved with this new approach because they will be included in this framework as a particular case. We focus on an application in a multi-person decision-making in political management.

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

aggregation operators
multi-person decision-making


Importance sampling for spatial scan analysis: computing scan statistic p-values for marked point processes Each point in an observed point pattern representing potential target detections (e.g., mines for minefield detection and localization) often is accompanied by a scalar 'mark' representing the detector's level of confidence in that particular detection. Scan analysis for clustering should take this additional mark information into account. We present an importance sampling method for deciding, based on an observed marked point pattern, if a scan statistic S provides significant evidence of increased activity in some localized region of time or space. Our method allows consideration of scan statistics based simultaneously on multiple scan geometries. Our approach yields an unbiased p-value estimate of the form P[S greater than or equal to s(observed)] = B*rho, where B* plays the role of the Bonferroni upper bound and the correction factor rho measures the conservativeness of this upper bound. The variance of our importance sampling estimate in typically smaller than that of the naive hit-or-miss Monte Carlo technique when the p-value is small. Furthermore, our estimate is often accurate for critical values which are not far enough in the tails of the null distribution to allow for accurate approximations via extreme value theory. In this article, we develop our importance sampling p-value estimator for the case of marked spatial Poisson processes using multiple scan geometries, and illustrate the approach via application to minefield reconnaissance. (C) 2001 Elsevier Science B.V. All rights reserved.

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

spatial scan analysis
importance sampling
marked point pattern
minefield


Adaptive bitstream switching of scalable video ? With scalable video coding that provides fine-granular quality degradation, such as fine granularity scalability (FGS) and progressive FGS (PFGS), or H.264 scalable video coding's (SVC) adaptive reference FGS (AR-FGS) coding, video can flexibly be streamed to receivers of heterogeneous bandwidths. However, the transmitted video is only efficiently encoded when the transmission bit rate is in the vicinity of the encoding bit rate. In this paper, we develop and evaluate a comprehensive suite of network-aware adaptive bitstream switching policies for point-to-point and point-to-multipoint streaming of fine granular scalable coded video to address this coding efficiency issue. Our approach stores a small number of encodings (versions) with different encoding bit rates for each video sequence and estimates the reconstructed quality using the motion activity levels of the underlying visual content (or, in general, any content descriptor(s) that highly correlate with the reconstructed quality). For unicast streaming, we then: (i) adaptively switch between the different encodings at the server, to improve the reconstructed video quality and (ii) adaptively drop packets during network congestion to ensure fairness between multiple unicast streams. For multicast streaming, we also adaptively switch between the different encodings to maximize the average video quality. Our adaptive bitstream switching policies consider the visual content descriptors as well as the network channel variability, while requiring only sample points from the rate-distortion curve of the video stream. From our extensive simulations with PFGS coding, we find that our adaptive unicast bitstream switching policy achieves on average a 0.8dB improvement over the optimal non-adaptive streaming for a diverse 200-shot sequence from Star Wars IV. We have also verified our key findings with the latest scalable video coding standard, H.264 SVC.

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

adaptive streaming
congestion control
simulcast
svc ar-fgs


model-theoretic semantics for the web Model-theoretic semantics is a formal account of the interpretations of legitimate expressions of a language. It is increasingly being used to provide Web markup languages with well-defined semantics. But a discussion of its roles and limitations for the Semantic Web has not yet received a coherent and detailed treatment. This paper takes the first steps towards such a treatment. The major result is an introductory explication of key ideas that are usually only implicit in existing accounts of semantics for the Web. References to more detailed accounts of these ideas are also provided. The benefit of this explication is increased awareness among Web users of some important issues inherent in using model-theoretic semantics for Web markup languages.

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


expressing territoriality in collaborative activity Territoriality, the expression of ownership towards an object, can emerge when social actors occupy a shared social space. In my research, I extend the study of territoriality beyond previous work in physical space in two key ways: 1) the object in question is virtual and 2) the social context is an online community engaged in collaborative activity. To do this, I observe the emergence of characteristic territorial behaviors (e.g. marking, control, defense) within collaborative authoring and social tagging. My dissertation then uses these observations to construct a theoretical framework for online territoriality to provide researchers and designers of groupware with guidelines with which to encourage ownership expression when appropriate.

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

social tagging
territoriality
ownership
collaborative authoring


The complexity of finding paths in graphs with bounded independence number We study the problem of finding a path between two vertices in finite directed graphs whose independence number is bounded by some constant k. The independence number of a graph is the largest number of vertices that can be picked such that there is no edge between any two of them. The complexity of this problem depends on the exact question we ask: Do we wish only to tell whether a path exists? Do we also wish to construct such a path? Are we required to construct the shortest one? Concerning the first question, we show that the reachability problem is first-order definable for all k and that its succinct version is Pi(2)(P)-complete for all k. In contrast, the reachability problems for many other types of finite graphs, including dags and trees, are not first-order definable, and their succinct versions are PSPACE-complete. Concerning the second question, we show not only that we can construct paths in logarithmic space, but that there even exists a logspace approximation scheme for this problem. The scheme gets a ratio r>1 as additional input and outputs a path that is at most r times as long as the shortest path. Concerning the third question, we show that even telling whether the shortest path has a certain length is NL-complete and thus is as difficult as for arbitrary directed graphs.

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

connectivity
shortest paths
distance in graphs
tournaments
first-order definability
polynomial hierarchy
completeness
approximation algorithms
succinct representations


recent database challenges in china on data consolidation and integration During the first phase of IT exploitation in China, a lot of isolated systems were developed and deployed over all the sites where the business took place. Each system typically dealt with one simple local business application. Since the mid 90's, data consolidation and data integration became critical to address the business need for cheaper cost, shorter time to the market as well as better business decision and control. Without consolidated and integrated data, there is no way to support new and complex applications for rapid and large scale business growth in China across lots of industries such as financial, telecom, government, manufacture and distribution. When database is used for companies and government agencies in China, the large Chinese population makes the database volume huge. A nation-wide bank or an insurance company has hundreds of millions accounts easily. A province-level telecom service provider has tens of millions subscribers. In certain domains, such as banking and telecom, many applications are executed as on-line transactions which ask for large transaction throughput with good response time. A province-level telecom service provider expects to handle up to 100 billion calls in a month. In this case, most of the phone calls will be pre-paid type and these calls need to be handled in near-real time. In order to satisfy the performance requirement, some applications implement application cache on application servers. This approach improves the application performance in getting data but it also introduces the complexity and longer delay when a failure in application occurs. Database management systems can provide client cache for powerful application servers in these days. As more and more application servers are added to respond large number of concurrent users and high volume transaction throughput, database management system must be highly scalable. Both logical and physical contentions should be avoided or greatly reduced. Continuous availability and high reliability are more critical for a consolidated large database because many users and applications rely on it. Both planned outage and unplanned outage should be avoided or minimized through appropriate duplication and redundancy. Smooth transition through cooperative versions of data helps reduce planned outages. Swift switch over to hot stand-by database system helps minimize the unplanned outages. Database management systems are expected to be autonomic and remain healthy in resource utilization with minimal administrative involvement. As a summary, data consolidation in China asks for low-cost, high performance database systems with high scalability, availability and reliability on very large database volume. Data integration in China often deals with both a horizontal layer of multiple lines of business and a vertical organizational structure. For government agencies, there are at least four levels across nation, province, district and county. There are a few industry specific data models and solutions to address the requirements of data integration. However, a common data integration platform has been constantly requested by many IT projects of large scale. In many cases, business control processes need to integrate business operation processes to support near-real time decision and control. There is a high demand for a practical and well-proven methodology with tool sets which can support data integration life cycle of architect, design, development, deployment and change management. Rapid economic and business growth in combination of the join to WTO created big demand in IT evolution across China business, industry and government. There are many demands and opportunities of data consolidation and integration with large data volume and system complexity. The demand of low-cost solutions makes it even more challenging.

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

data center consolidation
information integration


Equivalence transformation for the filtration problem In this paper, I am considering a filtration equation, and by using Ovsiannikov's method, I intend to construct the most general equivalence algebra. Moreover, some algorithms are performed in order to extend the principal algebra. (C) 1999 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 O O O O O O

dimensional motion of a gas
group classification
similarity solutions


Prioritizing tests for software fault diagnosis During regression testing, test prioritization techniques select test cases that maximize the confidence on the correctness of the system when the resources for quality assurance (QA) are limited. In the event of a test failing, the fault at the root of the failure has to be localized, adding an extra debugging cost that has to be taken into account as well. However, test suites that are prioritized for failure detection can reduce the amount of useful information for fault localization. This deteriorates the quality of the diagnosis provided, making the subsequent debugging phase more expensive, and defeating the purpose of the test cost minimization. In this paper we introduce a new test case prioritization approach that maximizes the improvement of the diagnostic information per test. Our approach minimizes the loss of diagnostic quality in the prioritized test suite. When considering QA cost as a combination of testing cost and debugging cost, on our benchmark set, the results of our test case prioritization approach show reductions of up to 60% of the overall combined cost of testing and debugging, compared with the next best technique. Copyright 2011 John Wiley & Sons, Ltd.

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


Probing the structure of Leishmania major DHFR TS and structure based virtual screening of peptide library for the identification of anti-leishmanial leads Leishmaniasis, a multi-faceted ethereal disease is considered to be one of the World's major communicable diseases that demands exhaustive research and control measures. The substantial data on these protozoan parasites has not been utilized completely to develop potential therapeutic strategies against Leishmaniasis. Dihydrofolate reductase thymidylate synthase (DHFR-TS) plays a major role in the infective state of the parasite and hence the DHFR-TS based drugs remains of much interest to researchers working on Leishmaniasis. Although, crystal structures of DHFR-TS from different species including Plasmodium falciparum and Trypanosoma cruzi are available, the experimentally determined structure of the Leishmania major DHFR-TS has not yet been reported in the Protein Data Bank. A high quality three dimensional structure of L.major DHFR-TS has been modeled through the homology modeling approach. Carefully refined and the energy minimized structure of the modeled protein was validated using a number of structure validation programs to confirm its structure quality. The modeled protein structure was used in the process of structure based virtual screening to figure out a potential lead structure against DHFR TS. The lead molecule identified has a binding affinity of 0.51 nM and clearly follows drug like properties.

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

dihydrofolate reductase thymidylate synthase


Development of electrochemical copper deposition screening methodologies for next generation additive selection To reduce time-to-knowledge and costs associated with 300mm wafer processing a laboratory-scale copper electrochemical deposition (ECD) system was developed for screening new organic additives which promote bottom up fill in interconnect trenches and vias. This new setup enables working process conditions and functionality trends to be identified for experimental suppressors and levelers at leading edge feature sizes (sub 50nm). These results can then be transferred to the in-line copper plating tool for full wafer plating and further analytical testing. This paper presents results of a case study using both open source and proprietary chemistry, focusing on gap fill, throwing power, and mounding as performance metrics. Preliminary data on the transferability of process conditions to the full wafer tool are also presented.

O 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

damascene
32nm node
beaker plating
polyethylene glycol


Advances in network smart cards authentication Smart cards have been widely used as simple token hardware in authenticationn processes. Nevertheless, a new trend indicates a shift towards more enhanced cards with networking capabilities. We propose revising the usual focus on smart card authentication protocol designs, as well as highlighting the need to adapt to new trends. Our main objective is to define an authentication model that uses the card as a stand-alone supplicant in a mutual end-to-end authentication schema. We also propose a protocol architecture which allows us to integrate the smart card within the network in the authentication plane. Finally, this new approach to network smart cards authentication processes is applied to a practical electronic payment scenario. (C) 2007 Elsevier B.V. All rights reserved.

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

network smart cards
authentication protocol


Optimal scheduling in buffered WDM interconnects with limited range wavelength conversion capability All optical networking is a promising candidate for supporting high-speed communications because of the huge bandwidth of optics. In this paper, we study optimal scheduling in buffered WDM interconnects with limited range wavelength conversion capability. We formalize the problem of maximizing network throughput and minimizing total delay as a problem of finding an optimal matching in a weighted bipartite graph. We then give a simple algorithm, called the Scan and Swap Algorithm, that finds the optimal matching in O(kB) time, where k is the number of wavelengths per fiber and B is the buffer length, as compared to directly adopting other existing algorithms that need at least O(k(2)N(2) + k(2)BN) time, where N is the number of input fibers.

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

wavelength-division-multiplexing (wdm)
packet scheduling
limited range wavelength conversion
optical packet switching
optical interconnects
optical switching networks
optical buffering
packet loss probability


3-d graphic display of discrete spatial data by prism maps An efficient algorithm for displaying 3-D scenes showing a discrete spatially varying surface is described. Given a 2-D map or planar graph composed of polygons where each polygon has a positive real number attribute, a prism is erected on each polygon with height proportional to that attribute. The resulting 3-D scene is plotted with shading and hidden lines removed. Thus the spatial variation of the attribute may be quickly and intuitively grasped by the nontechnical observer. This has applications to areas such as geography if the map is a cartographic map, or to physics if the map diagrams the periodic table. The algorithm takes time O(N*log(N)) where N is the number of edges in the map. Most of the calculations can be done without knowing the prism heights so extra plots with different attributes for the prisms can be produced quickly. This algorithm has been implemented and tested on maps of up to 12000 edges.

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

shading
prism maps
applications
diagrams
maps
planar graph
attributes
polygon
map
spatial
variation
data
display
algorithm
surface

thematic mapping
efficiency
log
cartography
timing
graphics
3-d
hidden surface
perspective
posit
observability
physical


an automatic hardware-software partitioner based on the possibilistic programming. The problem of hardware-software partitioning in the design of embedded systems is addressed. Uncertainties about the performance of the options for realization are expressed in triangular possibilistic numbers. To handle such numbers an integer programming formulation of the partitioning problem is derived. This formulation can be converted into a possibilistic program without changing the asymptotic computational complexity. The approach is illustrated with results obtained with the receiver part of a transceiver of a wireless indoor spread spectrum system. This example and several other experiments have shown that these optimizations can reach solutions within seconds for designs of that complexity and above.

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

wireless
program
systems
design
performance
complexity
integer programming

partition
software
uncertainty
examples
optimality
experience
hardware
computational complexity
embedded systems


Presentations of finitely generated cancellative commutative monoids and nonnegative solutions of systems of linear equations Varying methods exist for computing a presentation of a finitely generated commutative cancellative monoid. We use an algorithm of Contejean and Devie [An efficient incremental algorithm for solving systems of linear diophantine equations, Inform. and Comput. 113 (1994) 143172] to show how these presentations can be obtained from the nonnegative integer solutions to a linear system of equations. We later introduce an alternate algorithm to show how such a presentation can be efficiently computed from an integer basis.

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


defining scenarios for mobile design and evaluation This paper presents results from the design experiences of several mobile applications. It starts by addressing the difficulties that emerged through the data gathering, prototyping and evaluation stages. We explain how these problems and challenges were tackled, resulting in the creation of a conceptual scenario generation and selection framework. The framework and suggested guidelines aim at aiding designers on the scenario generation and selection process during design and evaluation of mobile applications. We address several case studies in which these guidelines were applied, stressing their contributions and results.

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


Path planning directed motion control of virtual humans in complex environments ? Generate realistic motions naturally adapted to complex dynamic environment; Apply the optimal path planning to direct motion synthesis of virtual humans; SIPP is implemented for planning the optimal path in complex dynamic environment; Three types of control anchors are extracted to direct motion field synthesis; Both the optimal path and the realistic motions are guaranteed simultaneously.

B I O B I O O O O O O O O O O O O O O O O O O O B I O O B I O O O O O O O O O O O O O O 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 synthesis
motion control
path planning

virtual human
complex dynamic environments


Tool-assisted mesh generation based on a tissue-growth model An heuristic mesh generation technique is proposed that is based on the model of forced particle motion, an edgewise cell-splitting algorithm and a moving tool concept. The method differs from conventional mesh generators in that it uses outward growth of the mesh, in contrast to the inward growth used in traditional meshing techniques. The method does not require prior meshing and patching of two-dimensional (2D) boundary surfaces. Instead, it uses a pre-defined skeleton of one-dimensional segments, or an arbitrary tool motion in three-dimensional (3D) space. In this respect, the technique can be considered as a 3D extension of a 2D drawing tool and can find applications in virtual reality systems. The method also guarantees the smoothness of the outer boundary of the mesh at each step of mesh generation, which is not the case with traditional propagating-front methods. The approach is based on the model of tissue growth and is suitable for meshing complex networks of bifurcating branches commonly found in biological structures: blood vessels, lungs, neural networks, plants etc. The generated meshes were used in solving unsteady flow and particle transport problems in lungs.

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

continuum mechanics
bifurcations
computer simulation


Comparison of generic simulation models for water resource systems In water resource systems that frequently experience severe droughts, generic simulation models can provide useful information for developing drought mitigation measures. This paper is about modeling in practice rather than in theory. The emphasis is on the application of generic simulation models to a multi-reservoir and multi-use water system in Southern Italy where frequent droughts over the last two decades have necessitated the use of temporary and unsustainable user-supply restrictions. In particular, AQUATOOL (Valencia Polytechnic University), MODSIM (Colorado State University), RIBASIM (DELTARES), WARGI-SIM (University of Cagliari) and WEAP (Stockholm Environmental Institute) models are considered in a preliminary analysis, which considers series and parallel simple schemes and also evaluates the possibility of alternative plans and operating policies in complex real water system. Each model has its own characteristics and uses different approaches to define resources releases from reservoirs and allocation to demand centers. The proposed model comparison and application does not identify in detail all the features of each model, rather it provides insights as to how these generic simulation models implement and evaluate different operating rules.

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

decision support systems
water resources management
optimization


An elasticity model for High Throughput Computing clusters ? Different methods have been proposed to dynamically provide scientific applications with execution environments that hide the complexity of distributed infrastructures. Recently virtualization has emerged as a promising technology to provide such environments. In this work we present a generic cluster architecture that extends the classical benefits of virtual machines to the cluster level, so providing cluster consolidation, cluster partitioning and support for heterogeneous environments. Additionally the capacity of the virtual clusters can be supplemented with resources from a commercial cloud provider. The performance of this architecture has been evaluated in the execution of High Throughput Computing workloads. Results show that, in spite of the overhead induced by the virtualization and cloud layers, these virtual clusters constitute a feasible and performing HTC platform. Additionally, we propose a performance model to characterize these variable capacity (elastic) cluster environments. The model can be used to dynamically dimension the cluster using cloud resources, according to a fixed budget, or to estimate the cost of completing a given workload in a target time.

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

virtual machines
high throughput computing


Argument graph as a tool for promoting collaborative online reading This study explored how the construction of an argument graph promotes students' collaborative online reading compared to note-taking. Upper secondary school students (n?=?76) worked in pairs. The pairs were asked to search for and read source material on the Web for a joint essay and either construct an argument graph or take notes during online reading. The data consist of transcription protocols of student pairs' discussions and joint essays. The study indicated that argument graphs may be useful tools when teachers want students to pay attention to the argumentative content of online sources and to consider relations between arguments. Additionally, with argument graphs, teachers can support students' post-reading activities, such as source-based argumentative writing.

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


stippling by example In this work, we focus on stippling as an artistic style and discuss our technique for capturing and reproducing stipple features unique to an individual artist. We employ a texture synthesis algorithm based on the gray-level co-occurrence matrix (GLCM) of a texture field. This algorithm uses a texture similarity metric to generate stipple textures that are perceptually similar to input samples, allowing us to better capture and reproduce stipple distributions. First, we extract example stipple textures representing various tones in order to create an approximate tone map used by the artist. Second, we extract the stipple marks and distributions from the extracted example textures, generating both a lookup table of stipple marks and a texture representing the stipple distribution. Third, we use the distribution of stipples to synthesize similar distributions with slight variations using a numerical measure of the error between the synthesized texture and the example texture as the basis for replication. Finally, we apply the synthesized stipple distribution to a 2D grayscale image and place stipple marks onto the distribution, thereby creating a stippled image that is statistically similar to images created by the example artist.

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

texture analysis and synthesis
stipple mark distribution
statistical similarity
computer-generated stippling


The impact of real-time information on bus ridership in New York City This paper evaluates a natural experiment in New York City. The impact of real-time information (RTI) on bus ridership is assessed. The methodology is panel regression. Two fixed effects models show an increase in bus ridership attributable to RTI. The farebox revenue implications are also investigated.

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


Higher-order tangent and secant numbers In this paper, the higher-order tangent numbers and higher-order secant numbers, { T ( n , k ) } n , k = 0 ? and { S ( n , k ) } n , k = 0 ? , have been studied in detail. Several known results regarding T(n,k) T ( n , k ) and S(n,k) S ( n , k ) have been brought together along with many new results and insights and they all have been proved in a simple and unified manner. In particular, it is shown that the higher-order tangent numbers T(n,k) T ( n , k ) constitute a special class of the partial multivariate Bell polynomials and that S(n,k) S ( n , k ) can be computed from the knowledge of T(n,k) T ( n , k ) . In addition, a simple explicit formula involving a double finite sum is deduced for the numbers T(n,k) T ( n , k ) and it is shown that T(n,k) T ( n , k ) are linear combinations of the classical tangent numbers Tn T n .

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

tangent numbers of order k k k k k k k
secant numbers of order k k k k k k k
higher-order (or
generalized) tangent and secant numbers
derivative polynomials


P-closedness in L-fuzzy topological spaces A good definition of P-closedness is introduced and studied in L-fuzzy topological spaces, where L is a fuzzy lattice. (C) 2000 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 B I O O O O O O O O

l-fuzzy topology
p-closedness
good extension


Network Immunization with Distributed Autonomy-Oriented Entities Many communication systems, e. g., internet, can be modeled as complex networks. For such networks, immunization strategies are necessary for preventing malicious attacks or viruses being percolated from a node to its neighboring nodes following their connectivities. In recent years, various immunization strategies have been proposed and demonstrated, most of which rest on the assumptions that the strategies can be executed in a centralized manner and/or that the complex network at hand is reasonably stable (its topology will not change overtime). In other words, it would be difficult to apply them in a decentralized network environment, as often found in the real world. In this paper, we propose a decentralized and scalable immunization strategy based on a self-organized computing approach called autonomy-oriented computing (AOC) [1], [2]. In this strategy, autonomous behavior-based entities are deployed in a decentralized network, and are capable of collectively finding those nodes with high degrees of conductivities (i.e., those that can readily spread viruses). Through experiments involving both synthetic and real-world networks, we demonstrate that this strategy can effectively and efficiently locate highly-connected nodes in decentralized complex network environments of various topologies, and it is also scalable in handling large-scale decentralized networks. We have compared our strategy with some of the well-known strategies, including acquaintance and covering strategies on both synthetic and real-world networks.

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 B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O 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 search
autonomy-oriented computing
self-organization
positive feedback
scalable computing


The role of endoplasmic reticulum in genesis of complex oscillations in pancreatic beta-cells In this paper, Chay's bursting pancreatic beta-cell model is updated to include a role for [Ca2+](ER), the luminal calcium concentration in the endoplasmic reticulum (ER). The model contains a calcium current which is activated by voltage and inactivated by [Ca2+](i). It also contains a cationic nonselective current (I-NS) that is activated by depletion of luminal Ca2+ in the ER. In this model, [Ca2+](ER) oscillates slowly, and this slow dynamic drives electrical bursting and the [Ca2+](i) oscillations. This model is capable of providing answers to some puzzling phenomena, which the previous models could not (e.g., why do single pancreatic beta-cells burst with a low Frequency while the cells in an islet burst with a much higher frequency ?). Verification of the model prediction that [Ca2+](ER) is a primary oscillator that drives electrical bursting and [Ca2+](i) oscillations in pancreatic beta-cells awaits experimental testing. Experiments using fluorescent dyes such as mag-fura-2-AM could provide relevant information.

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

pancreatic beta-cells
intracellular calcium oscillation
cationic non-selective current


Inhibition of ATF4 Transcriptional Activity by FIAT/?-Taxilin Modulates Bone Mass Accrual The basic domain-leucine zipper protein, activating transcription factor 4 (ATF4), was recently shown to control key aspects of osteoblast biology. ATF4 regulates the timely onset of osteoblast differentiation, the synthesis of type I collagen, and the transcription of the osteocalcin and RANKL (receptor activator of NF?-B ligand) genes. Accordingly, the levels and activity of ATF4 are under tight control through mechanisms that include protein stability and phosphorylation. We have uncovered yet another mode of inhibition of ATF4 through its interaction with the leucine zipper protein FIAT (Factor Inhibiting ATF4-mediated Transcription, also described as ?-taxilin). FIAT/?-taxilin localizes to the nucleus in osteoblasts and dimerizes with ATF4 to form inactive dimers, because it does not contain a DNA-binding basic domain moiety. The interaction of FIAT/?-taxilin with ATF4 thus inhibits ATF4-mediated transcription. Transgenic mice overexpressing FIAT/?-taxilin show osteopenia and reduced expression of the ATF4 target gene, osteocalcin. Interestingly, FIAT/?-taxilin also interacts with the transcriptional co-activator ?NAC (Nascent polypeptide associated complex And Coactivator alpha), suggesting alternative, non-mutually exclusive mechanisms contributing to the inhibition of ATF4-dependent osteocalcin gene transcription by FIAT/?-taxilin

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

fiat/?-taxilin
?nac
osteoblast gene transcription


Nonlinear operator for oriented texture Texture is an important part of the visual world of animals and humans and their visual systems successfully detect, discriminate, and segment texture. Relatively recently progress was made concerning structures in the brain that are presumably responsible for texture processing, Neurophysiologists reported on the discovery of a new type of orientation selective neuron in areas V1 and V2 of the visual cortex of monkeys which they called grating cells. Such cells respond vigorously to a grating of bars of appropriate orientation, position and periodicity. In contrast to other orientation selective cells, grating cells respond very weakly or not at all to single bars which do not make part of a grating. Elsewhere we proposed a nonlinear model of this type of cell and demonstrated the advantages of grating cells with respect to the separation of texture and form information, In this paper, we use grating: cell operators to obtain features and compare these operators in texture analysis tasks with commonly used feature extracting operators such as Gabor-energy and co-occurrence matrix operators. For a quantitative comparison of the discrimination properties of the concerned operators a new method is proposed which is based on the Fisher linear discriminant and the Fisher criterion. The operators are also qualitatively compared with respect to their ability to separate texture from form information and their suitability for texture segmentation.

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

grating cells
texture analysis
visual cortex


A secure fragile watermarking scheme based on chaos-and-hamming code In this work, a secure fragile watermarking scheme is proposed. Images are protected and any modification to an image is detected using a novel hybrid scheme combining a two-pass logistic map with Hamming code. For security purposes, the two-pass logistic map scheme contains a private key to resist the vector quantization (VQ) attacks even though the embedding scheme is block independent. To ensure image integrity, watermarks are embedded into the to-be-protected images which are generated using Hamming code technique. Experimental results show that the proposed scheme has satisfactory protection ability and can detect and locate various malicious tampering via image insertion, erasing, burring, sharpening, contrast modification, and even though burst bits. Additionally, experiments prove that the proposed scheme successfully resists VQ attacks.

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

fragile watermarking
burst bits
logistic map
hamming code


An efficient implicit mesh-less method for compressible flow calculations A dual-time implicit mesh-less scheme is presented for calculation of compressible inviscid flow equations. The Taylor series least-square method is used for approximation of spatial derivatives at each node which leads to a central difference discretization. Several convergence acceleration techniques such as local time stepping, enthalpy damping and residual smoothing are adopted in this approach. The capabilities of the method are demonstrated by flow computations around single and multi-element airfoils at subsonic, transonic and supersonic flow conditions. Results are presented which indicate good agreements with other reliable finite-volume results. The computational time is considerably reduced when using the proposed mesh-less method compared with the explicit mesh-less and finite-volume schemes using the same point distributions. Copyright (C) 2010 John Wiley & Sons, Ltd.

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

mesh-less method
implicit method
euler equations


A statistical tolerancing approach for design of synchronized supply chains Supply chain (SC) can be visualized as a means to fulfilling the customer's requirement with the objective to maximize the overall value generated. With the rapid change of world economy, firms need to deploy alternative methodologies to improve the responsiveness of SC. In this regard, one important issue is the synchronization and co-ordination of supply chain network (SCN). In order to ensure the dispatch of finished product to the customer, with in customers specified delivery window, with a fierce high probability, the delivery performance of any SCN is to be minimized by forcing the work in the system. These requirements can be achieved by SC coordination, where timing of the actions performed by each of the business entities must be perfectly synchronized in SCN. This research is first of its kind where a probabilistic model is conceptualized to allocate the tolerances on lead times of internal business processes of a SCN. Various linear and nonlinear constraints have been considered with an end goal of minimizing the total cost of given network. In the proposed approach, synchronization among the members of SC has been achieved in the similar fashion as that of tolerance allocation on mechanical assemblies. The effectiveness of the proposed model is illustrated with a case study. The probabilistic model for ensuring synchronization shows much promise for improving the entire performance of network in terms of greater profit, speed, flexibility, quality, and product development etc., in a long run manufacturing enterprise.

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

supply chain
tolerances
manufacturing enterprise


Using CMMI together with agile software development: A systematic review The search for adherence to maturity levels by using lightweight processes that require low levels of effort is regarded as a challenge for software development organizations. This study seeks to evaluate, synthesize, and present results on the use of the Capability Maturity Model Integration (CMMI) in combination with agile software development, and thereafter to give an overview of the topics researched, which includes a discussion of their benefits and limitations, the strength of the findings, and the implications for research and practice. The method applied was a Systematic Literature Review on studies published up to (and including) 2011. The search strategy identified 3193 results, of which 81 included studies on the use of CMMI together with agile methodologies. The benefits found were grouped into two main categories: those related to the organization in general and those related to the development process, and were organized into subcategories, according to the area to which they refer. The limitations were also grouped into these categories. Using the criteria defined, the strength of the evidence found was considered low. The implications of the results for research and practice are discussed. Agile methodologies can be used by companies to reduce efforts in getting to levels 2 and 3 of CMMI, there even being reports of applying agile practices that led to achieving level 5. However, agile methodologies alone, according to the studies, were not sufficient to obtain a rating at a given level, it being necessary to resort to additional practices to do so.

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

cmmi
benefits
limitations
systematic review

software process improvement
agile methodology


a multi-agent reinforcement learning method for a partially-observable competitive game This article proposes a reinforcement learning (RL) method based on an actor-critic architecture, which can be applied to partially-observable multi-agent competitive games. As an example, we deal with a card game Hearts. In our method, the actor plays so as to enlarge the expected temporal-difference error, which is obtained based on the estimation of the state transition. The state transition is estimated by taking the inferred card distribution and the other player's action models into account.

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


Enhancements of Trapdoor Permutations We take a closer look at several enhancements of the notion of trapdoor permutations. Specifically, we consider the notions of enhanced trapdoor permutation (Goldreich, Foundation of Cryptography: Basic Applications, 2004) and doubly enhanced trapdoor permutation (Goldreich, Computational Complexity: A Conceptual Perspective, 2011) as well as intermediate notions (Rothblum, A Taxonomy of Enhanced Trapdoor Permutations, 2010). These enhancements arose in the study of Oblivious Transfer and NIZK, but they address natural concerns that may arise also in other applications of trapdoor permutations. We clarify why these enhancements are needed in such applications, and show that they actually suffice for these needs.

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

trapdoor permutations
oblivious transfer


Learning about evaluation and assessment: teacher's use of folksonomies and ontologies in an online narrative environment Building ontology in the domain of human sciences can be a difficult process because of the different meanings given to the same key concepts in these disciplines: in fact, shared meaning is an important element in knowledge construction between members of a community. In this paper, we propose a participatory social environment called EduOntoWiki where academic experts in the field of educational sciences develop lightweight ontologies that members of multiple communities of practice (teachers, trainers, etc.) can modify and integrate using a folksonomic and storytelling approach. In this way, real-life narrative contexts become precious tagged alternative representations that can contribute to the ontology construction process. Experience of the environment gave possible indications regarding its use in teachers' training courses and as a useful tool to discuss evaluation and assessment issues in teachers' professional practice.

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

evaluation folksonomies ontologies teachers


intelligent interactions in email using social networks and ai This work is directed toward high-throughput email users, and uses machine learning and other artificial intelligence approaches to allow these users to triage and search email using automatically extracted social networks. While this approach makes use of (potentially) complex algorithms, these algorithms are abstracted through user interface design such that a non-technical user can take advantage of them, customizing when appropriate. My dissertation work will crystallize the needs of high-throughput email users into concrete tools to allow these users to better and more easily manage their information needs.

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

hci
intelligent user interfaces
personal information management


Parametric tabu-search for mixed integer programs A parametric form of tabu-search is proposed for solving mixed integer programming (MIP) problems that creates and solves a series of linear programming (LP) problems embodying branching inequalities as weighted terms in the objective function. The approach extends and modifies a parametric branch and bound procedure of Glover [Parametic branch and bound. OMEGA, The International Journal of Management Science 1978;6:19], replacing its tree search memory by the adaptive memory framework of tabu-search and introducing new associated strategies that are more flexible than the mechanisms of branch and bound. We also introduce new types of intensification and diversification procedures based on scatter search and frequency analysis, and also based on a variant of adaptive memory called model embedded memory. In one form this approach incorporates recency and frequency memory within the objective function structure of the parameterized LP formulations. In another form it generates valid inequalities from the optimized objective of the parameterized LP problem, and uses these as a supplement to traditional types of tabu memory. The integrated parametric approach affords a spectrum of variations that include useful simplifications for pure 0-1 MIP problems and problems with special structures, such as GUB constraints. The approach exploits both spatial and logical relationships, and is appropriate for discovering feasible solutions, as in the case of satisfiability problems. It is particularly designed to provide adaptive strategies for problems that are difficult for branch and bound and for branch and cut procedures, as opposed to problems these latter methods can handle effectively, and hence can be used to complement or supplement these more traditional types of methods.

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

mixed integer programming
adaptive memory


ON THE PERFORMANCE OF BINARY EXTREMAL SELF-DUAL CODES The decoding error probability of a code C measures the quality of performance when C is used for error correction in data transmission. In this note we compare different types of codes with regard to the decoding error probability.

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

binary self-dual extremal codes
decoding error probabilities


The trigonometric regressive spectral analysis - a method for mapping of beat-to-beat recorded cardiovascular parameters on to frequency domain in comparison with Fourier transformation Heart rate and peripheral blood pressure as physiological recorded vegetative parameters are very often rhythmically investigated with the Fourier Transformation (FT). In contrast to the original use of FT these parameters an still stochastic with overlaying rhythmical structures. The R-R intervals as independent variables of rime are not equidistant. The mathematical structure for the spectral decomposition is critically analysed. The purpose of this article is the presentation of a mathematical method, considering both the statistical and rhythmical features of such time series. On the basis of trigonometric regressions, this method is presented to eliminate the equidistance problems, arising with the usage of FT, by a new mathematical approach. This method computes more precisely the spectral power especially in the VLF range (0.003-0.04 Hz) than FT, because this method of trigonometric regression does not perform a frequency quantization. This method has been used and successfully tested for the analysis of peripheral blood pressure and R-R intervals including an effective reduction of input data. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.

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

heart rate variability
blood pressure variability
point events


Implementing a Regular Register in an Eventually Synchronous Distributed System Prone to Continuous Churn Due to their capability to hide the complexity generated by the messages exchanged between processes, shared objects are one of the main abstractions provided to developers of distributed applications. Implementations of such objects, in modern distributed systems, have to take into account the fact that almost all services, implemented on top of distributed infrastructures, are no longer fully managed due to either their size or their maintenance cost. Therefore, these infrastructures exhibit several autonomic behaviors in order to, for example, tolerate failures and continuous arrival and departure of nodes (churn phenomenon). Among all the shared objects, the register object is a fundamental one. Several protocols have been proposed to build fault resilient registers on top of message-passing system, but, unfortunately, failures are not the only challenge in modern distributed systems and new issues arise in the presence of churn. This paper addresses the construction of a multiwriter/multireader regular register in an eventually synchronous distributed system affected by the continuous arrival/departure of participants. In particular, a general protocol implementing a regular register is proposed and feasibility conditions associated with the arrival and departure of the processes are given. The protocol is proved correct under the assumption that a constraint on the churn is satisfied.

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

dynamic distributed systems
distributed algorithms


ranking retrieval systems without relevance judgments The most prevalent experimental methodology for comparing the effectiveness of information retrieval systems requires a test collection, composed of a set of documents, a set of query topics, and a set of relevance judgments indicating which documents are relevant to which topics. It is well known that relevance judgments are not infallible, but recent retrospective investigation into results from the Text REtrieval Conference (TREC) has shown that differences in human judgments of relevance do not affect the relative measured performance of retrieval systems. Based on this result, we propose and describe the initial results of a new evaluation methodology which replaces human relevance judgments with a randomly selected mapping of documents to topics which we refer to as pseudo-relevance judgments .Rankings of systems with our methodology correlate positively with official TREC rankings, although the performance of the top systems is not predicted well. The correlations are stable over a variety of pool depths and sampling techniques. With improvements, such a methodology could be useful in evaluating systems such as World-Wide Web search engines, where the set of documents changes too often to make traditional collection construction techniques practical.

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

affect
systems
methodology
performance
human
retrieval
text
relevance
practical
sampling
test collection
ranking
query

experimentation
search engine
evaluation/methodology
collect
correlation
map
relation
documentation
effect
world wide web
change
information retrieval


Environmental and organizational drivers influencing the adoption of VoIP Previous research recognized the importance of studying the organizational adoption of a new communication technology because of its potential benefits on the organizational and individual outcome. However, extant studies took into account just a single theoretical perspective lacking a more comprehensive overview of the factors, which may influence the intention to adopt a new communication technology. Since the growing interest of voice over IP (VoIP) we developed our theoretical framework and tested our hypotheses considering this emerging communication technology. Thus, the present research considers simultaneously the institutional, management fashion, and efficient-choice perspectives for understanding the drivers of VoIP adoption process. A theoretical model is developed and tested through structural equation modelling on 620 Italian firms. We hypothesize that both external and internal factors affect the intention to adopt VoIP. Results underscore both the importance of coercive and fashion setters pressure (i.e. external factors), and the pivotal role of perceived internal benefits (i.e. internal factors) in shaping intention to adopt.

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

intention to adopt
management fashion
voip

technology adoption
institutional perspective
efficient-choice


Solution of large quadratic knapsack problems through aggressive reduction The quadratic knapsack problem (QKP) calls for maximizing a quadratic objective function subject to a knapsack constraint. All coefficients are assumed to be nonnegative and all decision variables are binary. A new exact algorithm is presented, which makes use of aggressive reduction techniques to decrease the size of the instance to a manageable size. A cascade of upper bounds is used for the reduction, including an improved version of the Caprara-Pisinger-Toth bound based on upper planes and reformulation, and the Billionnet-Faye-Soutif bound based on Lagrangian decomposition. Generalized reduction techniques based on implicit enumeration are used to fix variables at their optimal values. In order to obtain lower bounds of high quality for the reduction, a core problem is solved, defined on a subset of variables. The core is chosen by merging numerous heuristic solutions found during the subgradient-optimization phase. The upper and lower bounding phases are repeated several times, each time improving the subgradient method used for finding the Lagrangian multipliers associated with the upper bounds. Having reduced the instance to a (hopefully) reasonable size, a branch and bound algorithm based on the Caprara-Pisinger-Toth framework is applied. Computational experiments are presented showing that several instances with up to 1,500 binary variables can be reduced to fewer than 100 variables. The remaining set of variables are easily handled through the exact branch and bound algorithm. In comparison to previous algorithms the framework does not only solve larger instances, but the algorithm also works well for instances with smaller densities of the profit matrix, which appear frequently when modeling various graph problems as quadratic knapsack problems.

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

programming, integer, algorithms, branch and bound

analysis of algorithms : computational complexity

programming, integer, algorithms, relaxation


Development of low-k precursors for next generation IC manufacturing The effect of the ligand structure in carbosilane chains with formula R1R2R3SiCxH2xSiR4R5R6 with x=1, 2 and R=H, Me, OEt is studied. The thermal characterization of the molecules as well as film characteristics is presented. It has been observed that partial incorporation of the carbon chain improves the mechanical properties of the film over commercial solutions. The optimization of the ligand choice enables to fine tune the film properties such as the dielectric constant, carbon content and mechanical properties.

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

low-k dielectric
sicsi precursors
pecvd deposition


ON THE MATHEMATICAL SYNTHESIS OF EQUATIONAL LOGICS We provide a mathematical theory and methodology for synthesising equational logics from algebraic metatheories. We illustrate our methodology by means of two applications: a rational reconstruction of Birkhoff's Equational Logic and a new equational logic for reasoning about algebraic structure with name-binding operators.

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

algebraic theories
soundness and completeness
rewriting
variable binding
alpha-equivalence


A Scilab program for computing general-relativistic models of rotating neutron stars by implementing Hartle's perturbation method We implement Hartle's perturbation method to the computation of relativistic rigidly rotating neutron star models. The program has been written in SCILAB ((C) INRIA-ENPC), a matrix-oriented high-level programming language. The numerical method is described in very detail and is applied to many models in slow or fast rotation. We show that, although the method is perturbative, it gives accurate results for all practical purposes and it should prove an efficient tool for computing rapidly rotating pulsars.

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

grt - methods
numerical - stars
neutron - stars


Semantics and Implementation of Continuous Sliding Window Queries over Data Streams In recent years the processing of continuous queries over potentially infinite data streams has attracted a lot of research attention. We observed that the majority of work addresses individual stream operations and system-related issues rather than the development of a general-purpose basis for stream processing systems. Furthermore, example continuous queries are often formulated in some declarative query language without specifying the underlying semantics precisely enough. To overcome these deficiencies, this article presents a consistent and powerful operator algebra for data streams which ensures that continuous queries have well-defined, deterministic results. In analogy to traditional database systems, we distinguish between a logical and a physical operator algebra. While the logical algebra specifies the semantics of the individual operators in a descriptive but concrete way over temporal multisets, the physical algebra provides efficient implementations in the form of stream-to-stream operators. By adapting and enhancing research from temporal databases to meet the challenging requirements in streaming applications, we are able to carry over the conventional transformation rules from relational databases to stream processing. For this reason, our approach not only makes it possible to express continuous queries with a sound semantics, but also provides a solid foundation for query optimization, one of the major research topics in the stream community. Since this article seamlessly explains the steps from query formulation to query execution, it outlines the innovative features and operational functionality implemented in our state-of-the-art stream processing infrastructure.

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

semantics
data streams
continuous queries
query optimization


Effective partitioning method for computing weighted Moore-Penrose inverse We introduce a method and an algorithm for computing the weighted Moore-Penrose inverse of multiple-variable polynomial matrix and the related algorithm which is appropriated for sparse polynomial matrices. These methods and algorithms are generalizations of algorithms developed in [M.B. Tasic, P.S. Stanimirovic, M.D. Petkovic, Symbolic computation of weighted Moore-Penrose inverse using partitioning method, Appl. Math. Comput. 189 (2007) 615-640] to multiple-variable rational and polynomial matrices and improvements of these algorithms on sparse matrices. Also, these methods are generalizations of the partitioning method for computing the Moore-Penrose inverse of rational and polynomial matrices introduced in [P.S. Stanimirovic, M.B. Tasic, Partitioning method for rational and polynomial matrices, Appl. Math. Comput. 155 (2004) 137-163; M.D. Petkovic, P.S. Stanimirovic, Symbolic computation of the Moore-Penrose inverse using partitioning method, Internat. J. Comput. Math. 82 (2005) 355-367] to the case of weighted Moore-Penrose inverse. Algorithms are implemented in the symbolic computational package MATHEMATICA. (C) 2007 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 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 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 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 B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

polynomial matrices
sparse matrices
symbolic computation

weighted moore-penrose inverse
rational matrices


quantifying human reconstruction accuracy for voxelcarving in a sporting environment Whilst voxel carving approaches exist that allow non-invasive 3D human reconstruction, their performance is heavily dependent on the number of cameras used and the placement of these cameras around the subject. We present a technique to quantify the fall-off in accuracy of spatially carved volumetric representations of humans based on real world constraints. We describe an example of such a quantitative evaluation using a synthetic dataset of typical sports motion in a tennis court scenario, created using computer graphics techniques and motion capture data. Experiments are performed using a baseline voxel carving technique that includes player tracking, background subtraction and player voxel carving. This type of quantitative evaluation could be used by amateur sporting clubs without a sophisticated capture infrastructure to understand how best to instrument a camera network in order to obtain a good trade-off between reconstruction accuracy and installation cost.

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

space carving
image processing
3d reconstruction


Bell polynomials and generalized Blissard problems We introduce two possible generalizations of the classical Blissard problem and we show how to solve them by using the second order and multi-dimensional Bell polynomials, whose most important properties are recalled. (C) 2010 Elsevier Ltd. All rights reserved.

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


efficient and cost-aware operator placement in heterogeneous stream-processing environments Operator placement for distributed stream-processing systems is still a challenging problem that can be modeled as a Task Assignment Problem (TAP). Multiple objectives are relevant for the optimization in heterogeneous stream-processing systems as there are different capabilities of the underlying networks and stream-processing nodes. We present an approach based on linear programming relaxation and iterative deterministic rounding. It uses an efficient linearization approach for the quadratic objective function that results from the TAP.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O 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 techniques
operator distribution
performance modeling
(self-)management
federated eventbased systems


Macroscopic entanglement We show how collective vibrational modes of two distant mirrors of an optical Fabry-Perot cavity can be entangled by the light bouncing between them. Such an entanglement can be demonstrated even at the macroscopic level of vibrational modes with an effective mass of the order of milligrams.

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

macroscopic quantum phenomena
radiation pressure


Active control of axisymmetric shells with piezoelectric layers: a mixed laminated theory with a high order displacement field This paper presents the development of a semi-analytical axisymmetric shell finite element model with embedded and/or surface bonded piezoelectric ring actuators and/or sensors for active damping vibration control of the structure. A mixed finite element approach is used, which combines the equivalent single-layer higher order shear deformation theory, to represent the mechanical behavior with a layerwise discretization in the thickness direction to represent the distribution of the electric potential of each piezoelectric layer of the frusta conical finite element. To achieve a mechanism of active control of the dynamic response of the structure a feedback control algorithm is used coupling the sensor and active piezoelectric layers. Two illustrative examples are presented and discussed.

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

high order theory
piezoelectric laminates


Highly Acyclic Groups, Hypergraph Covers, and the Guarded Fragment We construct finite groups whose Cayley graphs have large girth even with respect to a discounted distance measure that contracts arbitrarily long sequences of edges from the same color class ( subgroup), and only counts transitions between color classes (cosets). These groups are shown to be useful in the construction of finite bisimilar hypergraph covers that avoid any small cyclic configurations. We present two applications to the finite model theory of the guarded fragment: a strengthening of the known finite model property for GF and the characterization of GF as the guarded bisimulation invariant fragment of first-order logic in the sense of finite model theory.

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

finite model theory
groups of large girth
expressive completeness