ppxscal/embedding_network huggingface dataset:
Augmented CRL Scheme
Authors: A. Lakshminarayanan
Venue: Proceeding of the 2005 conference on Applied Public Key Infrastructure: 4th International Workshop: IWAP 2005 (2005)

PKI based applications use digitally signed certificates to bind public keys to user identities. Some digital certificates need to be revoked before their scheduled expiry. Certificate revocation is an important yet burdensome aspect of PKI. In this paper, we present the augmented CRL scheme, a simple yet novel extension to delta-CRLs. Using this scheme, certificate verifying clients need not download base CRLs yet can construct the same using augmented CRLs. We exploit the similarity between X.509 base and delta-CRL data structures. We show that the augmented CRL scheme provides significant bandwidth savings compared to existing CRL based schemes. The amount of downloaded CRL data is also much less compared to earlier schemes. Our scheme is simple, scalable and can easily be integrated into existing CRL based revocation schemes.
"It has to be a group work!": co-design with children
Authors: Kirsikka Vaajakallio, Jung-Joo Lee, Tuuli Mattelmäki
Venue: Proceedings of the 8th International Conference on Interaction Design and Children (2009)

Design researchers are increasingly interested in techniques that support creative teams in various design processes. The methods developed for sharing knowledge and generating solutions are mostly focusing on adults. Creative collaboration with and among children have a specific set of challenges to be considered. In this paper, we describe two design experiments that were conducted with children aged 7 to 9, to explore the applications of co-design methods with children. In those experiments, we observed that children are capable of utilizing make tools but have challenges in group dynamics and reflecting everyday experiences into design ideas.
An adaptive multi-strategy approach for semantic mapping
Authors: Youssef Bououlid Idrissi, Julie Vachon
Venue: Proceedings of the 2nd Canadian Conference on Computer Science and Software Engineering (2009)

Semantic mapping is a fundamental step towards application interoperability, data integration and service oriented computing over the Internet. It consists in matching semantically equivalent concepts coming from heterogeneous data sources. This basic task is nevertheless tedious and often error prone if handled manually. Therefore, many systems have been developed for its automation. However, virtually all solutions currently target a specific type of applications and rely on rigid approaches applying, without distinction, the same matching technique with the same fixed procedures on data to be aligned without regard for their characteristics. The problem is that such mapping systems are not adapted to the diversity of Internet where data sources and domains are numerous, highly heterogeneous and often changing. This article presents INDIGO, an adaptive mapping solution which takes into account the diversified nature of data sources that are shared over the Internet. It provides multiple matching strategies which can be flexibly combined to take into consideration the specificities of the data sources being aligned.
Order Statistics in the Farey Sequences in Sublinear Time and Counting Primitive Lattice Points in Polygons
Authors: Jakub Pawlewicz, Mihai P&#x0103;tra&#x015f;cu
Venue: Algorithmica (2009)

We present the first sublinear-time algorithms for computing order statistics in the Farey sequence and for the related problem of ranking. Our algorithms achieve a running times of nearly O(n 2/3), which is a significant improvement over the previous algorithms taking time O(n). We also initiate the study of a more general problem: counting primitive lattice points inside planar shapes. For rational polygons containing the origin, we obtain a running time proportional to D 6/7, where D is the diameter of the polygon.
System Support of Diabetic Self-treatments Using Mobile Phones
Authors: Takuya Yoshihiro, Kazuhiro Ikemoto, Kumiko Mori, Sachiko Kagawa, Yasuhisa Yamamoto, Masaru Nakagawa
Venue: Proceeding of the 2006 conference on Knowledge-Based Software Engineering: Proceedings of the Seventh Joint Conference on Knowledge-Based Software Engineering (2006)

We developed a system which helps diabetic people making self-treatments in their home, by exchanging treatment information and advices with their doctors and nurses in the hospital. To cure diabetes, it is essential to make daily treatment such as improving meals, doing exercises, taking insulin, or taking medicines to keep blood glucose level in a proper range. However, since many of diabetic people do not go to see their doctor frequently, say, about once a month, they tend to be lazy about self-treatments during that long period of time. As a result, many people are suffering from diabetes long time. To improve this situation, we developed the system to help self-treatments. In our system, patients report their concrete treatment activities to their doctors using mobile phones. The doctors watch the reports and make proper encouraging advices to the patients. We expect that such kind of advices can raise patients' motivation for their self-treatments. In designing the system, we tried to have doctors understand the concrete activities of patients' self-treatments through patients' daily reports, so that doctors can make proper and effective advices and encouragements. In this paper, we introduce the new diabetic self-treatment supporting system and report the evaluation results through a short-term test operation with several patients.
H ∞ Synchronization of General Discrete-Time Chaotic Neural Networks with Time Delays
Authors: Meiqin Liu, Senlin Zhang, Meikang Qiu
Venue: Proceedings of the 6th International Symposium on Neural Networks on Advances in Neural Networks (2009)

This paper investigates robust H ∞ synchronization problem of general discrete-time time-delayed chaotic neural networks with external disturbance. Based on Lyapunov stability theory and H ∞ control concept, time-delayed state feedback controllers are established to not only guarantee exponential stable synchronization between two general chaotic neural networks with time delays, but also reduce the effect of external disturbance on synchronization error to a minimal H ∞ norm constraint. The control design problem is shown to be a linear matrix inequality (LMI) standard problem which can be easily solved by various convex optimization algorithms to determine the optimal H ∞ synchronization control law.
Fast Communication: Computational load reduction in decision functions using support vector machines
Authors: J. Acevedo-Rodríguez, S. Maldonado-Bascón, S. Lafuente-Arroyo, P. Siegmann, F. López-Ferreras
Venue: Signal Processing (2009)

A new method of reducing the computational load in decision functions provided by a support vector classification machine is studied. The method exploits the geometrical relations when the kernels used are based on distances to obtain bounds of the remaining decision function and avoids to continue calculating kernel operations when there is no chance to change the decision. The method proposed achieves savings in operations of 25-90% whilst keeping the same accuracy. Although the method is explained for support vector machines, it can be applied to any kernel binary classifier that provides a similar evaluation function.
Assessing the aggregation of parameterized imprecise classification
Authors: Isabela Drummond, Joaquim Melendez, Sandra Sandri
Venue: Proceeding of the 2006 conference on Artificial Intelligence Research and Development (2006)

This work is based on classifiers that can yield possibilistic valuations as output, that may have been obtained from a labeled data set either directly as such, by possibilistic classifiers, or by transforming the output of probabilistic classifiers or else by adapting prototype-based classifiers in general. Imprecise classifications are elicited from the possibilistic valuations by varying a parameter that makes the overall classification become either more or less precise. We discuss some accu-racy measures to assess the quality of the parameterized imprecise classifications, thus allowing the user to choose the most suitable level of imprecision for a given application. Here we particularly address the issue of aggregating parameterized aggregation classifiers, and assessing their performance.
Control Theory of Multi-fingered Hands: A Modelling and AnalyticalMechanics Approach for Dexterity and Intelligence, 1st edition
Authors: Suguru Arimoto
Venue:  (2007)

The hand is an agency of the brain; it reflects activities of the brain and thereby can be seen as a mirror to the mind. The dexterity of the hand has been investigated widely in developmental psychology and in anthropology. Since robotics launched in the mid-1970s, numerous multi-fingered hands mimicking the human hand have been designed and made in a number of universities and research institutes, in addition to sophisticated prosthetic hands with plural fingers. Control Theory of Multi-fingered Hands presents a comprehensive insight into the intelligence and dexterity of robotic multi-fingered hands from both the physical and control- theoretic viewpoints. The book: focuses on the problem of how to control dexterous movements of fingers interacting with an object in the execution of everyday tasks; clarifies what kinds of sensory-motor coordinated signals are necessary and sufficient for realising stable grasping and/or object manipulation, in particular, the synergistic choices of control gains in co-activation signals for finger muscles and tendons crucial in realising secure pinching motions; derives a mathematical model of the dynamics of a complicated mechanism of multiple fingers with multiple joints physically interacting; and, considers the problem of how to recreate the function of "blind grasping". Control Theory of Multi-fingered Hands will be a useful reference for postgraduate students and researchers in this field, as well as engineers and roboticists.
On the copositive representation of binary and continuous nonconvex quadratic programs
Authors: Samuel Burer
Venue: Mathematical Programming: Series A and B (2009)

In this paper, we model any nonconvex quadratic program having a mix of binary and continuous variables as a linear program over the dual of the cone of copositive matrices. This result can be viewed as an extension of earlier separate results, which have established the copositive representation of a small collection of NP-hard problems. A simplification, which reduces the dimension of the linear conic program, and an extension to complementarity constraints are established, and computational issues are discussed.
A Novel MAC scheme for solving the QoS parameter adjustment problem in IEEE 802.11e EDCA
Authors: Thomas Nilsson, Jahanzeb Farooq
Venue: Proceedings of the 2008 International Symposium on a World of Wireless, Mobile and Multimedia Networks (2008)

We present a novel MAC scheme for solving the QoS parameter adjustment problem in IEEE 802.11e EDCA. The default values of the QoS parameters in EDCA, Contention Window (CW), arbitration Interframe Space (IFS) etc only yield good performance for few scenarios. We first propose a simple adaptation scheme, called a-EDCA, where the access point adapts the CWs based on the network conditions. The main contribution of this work is the second approach, called i-EDCA, where we make modifications to the back-off phase of EDCA and introduce a random IFS scheme. Simulation results show that both approaches result in stable capacity ratios between priority classes and very high channel utilization, compared to EDCA, when the number of stations is increased. Moreover, i-EDCA yields close to optimal channel utilization for a large number of scenarios without any need of adapting the parameters. In i-EDCA, the capacity for each class is directly proportional to its CW. Results also show that i-EDCA has improved fairness and prevents low priority classes to be starved under higher loads, a problem found in EDCA.
Dealings with problem hardness in genetic algorithms
Authors: Stjepan Picek, Marin Golub
Venue: WSEAS Transactions on Computers (2009)

Genetic algorithms (GA) have been successfully applied to various problems, both artificial as well as real-world problems. When working with GAs it is important to know those those kinds of situations when they will not find the optimal solution. In other words, to recognize problems that are difficult for a GA to solve. There are various reasons why GAs will not converge to optimal solutions. By combining one or more of these reasons a problem can become a GA-hard problem. Today, there are numerous methods for solving GA-hard problems; every measure has its specific advantages and drawbacks. In this work the effectiveness of one of these measures is evaluated, namely the Negative Slope Coefficient (NSC) measure. A different measure is proposed, called the New Negative Slope Coefficient (NNSC) measure, which aims to address certain drawbacks of the original method. Possible guidelines for further development of this, and comparable methods are proposed.
On the chromatic number of a random 5-regular graph
Authors: J. Díaz, A. C. Kaporis, G. D. Kemkes, L. M. Kirousis, X. Pérez, N. Wormald
Venue: Journal of Graph Theory (2009)

It was only recently shown by Shi and Wormald, using the differential equation method to analyze an appropriate algorithm, that a random 5-regular graph asymptotically almost surely has chromatic number at most 4. Here, we show that the chromatic number of a random 5-regular graph is asymptotically almost surely equal to 3, provided a certain four-variable function has a unique maximum at a given point in a bounded domain. We also describe extensive numerical evidence that strongly suggests that the latter condition holds. The proof applies the small subgraph conditioning method to the number of locally rainbow balanced 3-colorings, where a coloring is balanced if the number of vertices of each color is equal, and locally rainbow if every vertex is adjacent to at least one vertex of each of the other colors. &copy; 2009 Wiley Periodicals, Inc. J Graph Theory 61: 157&ndash;191, 2009
Motivating Appropriate Challenges in a Reciprocal Tutoring System
Authors: Ari Bader-Natal, Jordan Pollack
Venue: Proceeding of the 2005 conference on Artificial Intelligence in Education: Supporting Learning through Intelligent and Socially Informed Technology (2005)

Formalizing a student model for an educational system requires an engineering effort that is highly domain-specific. This model-specificity limits the ability to scale a tutoring system across content domains. In this work we offer an alternative, in which the task of student modeling is not performed by the system designers. We achieve this by using a reciprocal tutoring system in which peer-tutors are implicitly tasked with student modeling. Students are motivated, using the Teacher's Dilemma, to use these models to provide appropriately-difficult challenges. We implement this as a basic literacy game in a spelling-bee format, in which players choose words for each other to spell across the internet. We find that students are responsive to the game's motivational structure, and we examine the affect on participants' spelling accuracy, challenge difficulty, and tutoring skill.
Generic and reflective graph transformations for checking and enforcement of modeling guidelines
Authors: Elodie Legros, Carsten Amelunxen, Felix Klar, Andy Schürr
Venue: Journal of Visual Languages and Computing (2009)

In the automotive industry, the model driven development of software, today considered as the standard paradigm, is generally based on the use of the tool MATLAB Simulink/Stateflow. To increase the quality, the reliability, and the efficiency of the models and the generated code, checking and elimination of detected guideline violations defined in huge catalogs has become an essential task in the development process. It represents such a tremendous amount of boring work that it must necessarily be automated. In the past we have shown that graph transformation tools like Fujaba/MOFLON allow for the specification of single modeling guidelines on a very high level of abstraction and that guideline checking tools can be generated from these specifications easily. Unfortunately, graph transformation languages do not offer appropriate concepts for reuse of specification fragments-a MUST, when we deal with hundreds of guidelines. As a consequence we present an extension of MOFLON that supports the definition of generic rewrite rules and combines them with the reflective programming mechanisms of Java and the model repository interface standard Java Metadata Interface (JMI).
Determining configuration parameter dependencies via analysis of configuration data from multi-tiered enterprise applications
Authors: Vinod Ramachandran, Manish Gupta, Manish Sethi, Soudip Roy Chowdhury
Venue: Proceedings of the 6th international conference on Autonomic computing (2009)

Multi-tiered enterprise applications, which comprise of many (heterogeneous and possibly loosely coupled) components at various layers of the IT stack, typically have configuration dependencies between these different components. A change in the value of a configuration parameter of a component may require changing one or more parameters of other components to the same value. Keeping track of these dependencies is not a mean task as they are typically cross product and requires in-depth product/system knowledge. Our aim in this paper is to introduce techniques that do not require a system administrator to have in-depth knowledge about a multi-tiered system in order to be aware of the possible configuration dependencies in a system. Our focus in this paper does not include, for example, the performance-related dependencies such as the one that exists between the maximum number of threads and session timeout in an Apache server. In this paper we provide a method for analyzing existing deployments (that are functioning properly) to infer the configuration dependencies in a probabilistic sense. Firstly, we analyze the values of the configuration parameters of the various components to determine a candidate list of dependencies which includes both true and false ones. We then provide a heuristic that makes use of the statistics on the parameter name and value strings, computed from the configuration data and also the information on the web, to compute a rank for a dependency to be true. We provide a rank-ordered list of dependencies so that administrators can consult it to quickly and systematically identify the true dependencies. To complement our proposed approach we have performed an extensive study and experimentation to show the efficacy of our technique on data from two real-world solutions.
On-line learning and modulation of periodic movements with nonlinear dynamical systems
Authors: Andrej Gams, Auke J. Ijspeert, Stefan Schaal, Jadran Lenarčič
Venue: Autonomous Robots (2009)

The paper presents a two-layered system for (1) learning and encoding a periodic signal without any knowledge on its frequency and waveform, and (2) modulating the learned periodic trajectory in response to external events. The system is used to learn periodic tasks on a humanoid HOAP-2 robot. The first layer of the system is a dynamical system responsible for extracting the fundamental frequency of the input signal, based on adaptive frequency oscillators. The second layer is a dynamical system responsible for learning of the waveform based on a built-in learning algorithm. By combining the two dynamical systems into one system we can rapidly teach new trajectories to robots without any knowledge of the frequency of the demonstration signal. The system extracts and learns only one period of the demonstration signal. Furthermore, the trajectories are robust to perturbations and can be modulated to cope with a dynamic environment. The system is computationally inexpensive, works on-line for any periodic signal, requires no additional signal processing to determine the frequency of the input signal and can be applied in parallel to multiple dimensions. Additionally, it can adapt to changes in frequency and shape, e.g. to non-stationary signals, such as hand-generated signals and human demonstrations.
On the stability of the information carried by traffic flow features at the packet level
Authors: Alice Este, Francesco Gringoli, Luca Salgarelli
Venue: ACM SIGCOMM Computer Communication Review (2009)

This paper presents a statistical analysis of the amount of information that the features of traffic flows observed at the packet-level carry, with respect to the protocol that generated them. We show that the amount of information of the majority of such features remain constant irrespective of the point of observation (Internet core vs. Internet edge) and to the capture time (year 2000/01 vs. year 2008). We also describe a comparative analysis of how four statistical classifiers fare using the features we studied.
Type-safe dynamic protocol composition in Jgroup/ARM
Authors: Hein Meling, Alberto Montresor
Venue: Proceedings of the 3rd International DiscCoTec Workshop on Middleware-Application Interaction (2009)

Protocol composition is a common approach to structure protocols used by networked applications, and typically a vertically layered approach is taken. This paper presents an alternative approach, where the protocol composition is a weakly-coupled set of protocol modules organized in a non-hierarchical structure. Protocol modules are dynamically constructed at runtime. The approach is designed for systems that involves multiple communicating entities and multicast style interactions are supported, making the approach suitable for building reliable network applications. The main advantage of the approach is type-safety and that modules in the same composition communicate by direct interaction, whereas other frameworks typically use a vertically layered protocol stack, forcing all messages/events to pass through all intermediate layers introducing unnecessary delays.
Finding the best conic approximation to the convolution curve of two compatible conics based on Hausdorff distance
Authors: Seok Hur, Tae-wan Kim
Venue: Computer-Aided Design (2009)

We consider the convolution of two compatible conic segments. First, we find an exact parametric expression for the convolution curve, which is not rational in general, and then we find the conic approximation to the convolution curve with the minimum error. The error is expressed as a Hausdorff distance which measures the square of the maximal collinear normal distance between the approximation and the exact convolution curve. For this purpose, we identify the necessary and sufficient conditions for the conic approximation to have the minimum Haudorff distance from the convolution curve. Then we use an iterative process to generate a sequence of weights for the rational quadratic Bezier curves which we use to represent conic approximations. This sequence converges to the weight of the rational quadratic Bezier curve with the minimum Hausdorff distance, within a given tolerance. We verify our method with several examples.