ppxscal/embedding_network huggingface dataset:
Concept Lattices of Subcontexts of a Context
Authors: Xia Wang*, Wenxiu Zhang
Venue: Fundamenta Informaticae (2009)

As an effective tool for data analysis and knowledge processing, the theory of concept lattices has been studied extensively and applied to various fields. In order to discover useful knowledge, one often ignores some attributes according to a particular purpose and merely considers the subcontexts of a rather complex context. In this paper, we make a deep investigation on the theory of concept lattices of subcontexts. An approach to construct the concept lattice of a context is first presented by means of the concept lattices of its subcontexts. Then the concept lattices induced by all subcontexts of the context are considered as a set, and an order relation is introduced into the set. It is proved that the set together with the order relation is a complete lattice. Finally, the top element and the bottom element of the complete lattice are also obtained.
A priori implementation effort estimation for hardware design based on independent path analysis
Authors: Rasmus Abildgren, Jean-Philippe Diguet, Pierre Bomel, Guy Gogniat, Peter Koch, Yannick Le Moullec
Venue: EURASIP Journal on Embedded Systems (2008)

This paper presents a metric-based approach for estimating the hardware implementation effort (in terms of time) for an application in relation to the number of linear-independent paths of its algorithms. We exploit the relation between the number of edges and linear-independent paths in an algorithm and the corresponding implementation effort. We propose an adaptation of the concept of cyclomatic complexity, complemented with a correction function to take designers' learning curve and experience into account. Our experimental results, composed of a training and a validation phase, show that with the proposed approach it is possible to estimate the hardware implementation effort. This approach, part of our light design space exploration concept, is implemented in our framework "Design-Trotter" and offers a new type of tool that can help designers and managers to reduce the time-to-market factor by better estimating the required implementation effort.
Mobile Web services authentication using SAML and 3GPP generic bootstrapping architecture
Authors: Kalid Elmufti, Dasun Weerasinghe, M. Rajarajan, Veselin Rakocevic, Sanowar Khan, John A. MacDonald
Venue: International Journal of Information Security (2009)

In this paper we present a platform for the direct consumption of web services by a Mobile Station. We give an architectural solution where Mobile Operators play the role of Trusted Third Parties supplying service credentials that allow a co-located 3GPP Network Application Function and Liberty-enabled Identity Provider entity to implement a controlled Shopping Mall service to Mobile Stations from multiple trust domains. We consider both the protocol and the structure and syntax of the various tokens required to minimise service latency over the bandwidth and performance constrained mobile system, whilst providing adequate security services to protect against the perceived threat model. To validate our proposal we have developed code to create a Web Service test scenario using SAML authentication tokens utilising readily available J2ME, Java Card, J2SE and J2EE platforms, Web Services tools from Apache, the KToolBar emulator from Sun, and the JCOPS suite of tools for Java Card applet development.
How and why people Twitter: the role that micro-blogging plays in informal communication at work
Authors: Dejin Zhao, Mary Beth Rosson
Venue: Proceedings of the ACM 2009 international conference on Supporting group work (2009)

Micro-blogs, a relatively new phenomenon, provide a new communication channel for people to broadcast information that they likely would not share otherwise using existing channels (e.g., email, phone, IM, or weblogs). Micro-blogging has become popu-lar quite quickly, raising its potential for serving as a new informal communication medium at work, providing a variety of impacts on collaborative work (e.g., enhancing information sharing, building common ground, and sustaining a feeling of connectedness among colleagues). This exploratory research project is aimed at gaining an in-depth understanding of how and why people use Twitter - a popular micro-blogging tool - and exploring micro-blog's poten-tial impacts on informal communication at work.
On Exact Solutions to the Euclidean Bottleneck Steiner Tree Problem
Authors: Sang Won Bae, Chunseok Lee, Sunghee Choi
Venue: Proceedings of the 3rd International Workshop on Algorithms and Computation (2009)

We study the Euclidean bottleneck Steiner tree problem: given a set P of n points in the Euclidean plane, called terminals, find a Steiner tree with at most k Steiner points such that the length of the longest edge in the tree is minimized. This problem is known to be NP-hard even to approximate within ratio $\sqrt{2}$. We focus on finding exact solutions to the problem for a small constant k. Based on geometric properties of optimal location of Steiner points, we present an O(n logn) time exact algorithm for k = 1 and an O(n 2) time algorithm for k = 2. Also, we present an O(n logn) time exact algorithm to the problem for a special case where there is no edge between Steiner points.
Decomposition Structures for Event-B
Authors: Michael Butler
Venue: Proceedings of the 7th International Conference on Integrated Formal Methods (2009)

Event-B provides a flexible approach to modelling and refinement of systems. In this paper we outline two important ways in which Event-B refinement can be augmented with additional structuring to support further the management of complex refinements. Firstly we show how event refinement diagrams can be used to structure refinement steps involving decomposition of atomicity. Secondly we outline a technique for decomposing models into sub-models to allow for independent refinement. We show how these two structuring techniques can be used together.
Improved Hierarchical Network Model Based on Pastry Scheme
Authors: Jun Chen, Lei Wang
Venue: Proceedings of the 2009 Second International Workshop on Knowledge Discovery and Data Mining (2009)

The traditional Pastry design is a flat overlay network and limited-scope searching, in which all nodes have identical capabilities and responsibilities and all communication is symmetric. But in practice, because of a variety of available bandwidth and delay, each node has different capabilities. in this paper, a hierarchical Pastry network model is presented to address this limitation. Furthermore, the routing procedure and handling algorithm of the arrival and departure of nodes will be carefully discussed. Finally, some elementary experimental results obtained with a prototype implementation on JXTA platform indicate that the improved Pastry network model is superior in routing performance.
Explicit and Emergent Cooperation Schemes for Search Algorithms
Authors: Teodor Gabriel Crainic, Michel Toulouse
Venue: Learning and Intelligent Optimization: Second International Conference, LION 2007 II, Trento, Italy, December 8-12, 2007. Selected Papers (2008)

Cooperation as problem-solving and algorithm-design strategy is widely used to build methods addressing complex discrete optimization problems. In most cooperative-search algorithms, the explicit cooperation scheme yields a dynamic process not deliberately controlled by the algorithm design but inflecting the global behaviour of the cooperative solution strategy. The paper presents an overview of explicit cooperation mechanisms and describes issues related to the associated dynamic processes and the emergent computation they often generate. It also identifies a number of research directions into cooperation mechanisms, strategies for dynamic learning, automatic guidance, and self-adjustment, and the associated emergent computation processes.
2D conditional simulation of channels on wells using a random walk approach
Authors: Jiahua Wang, Xiangbo Wang, Changlin Ren
Venue: Computers Geosciences (2009)

Channel modeling is one of the popular topics in the application of geostatistics to fluvial reservoir modeling. This paper presents an approach to designing channels which have a general flow direction through sand well locations and which avoid shale well locations. This approach is named the random walk on graphs of well locations, and is applied to model channel reservoirs. This modeling process consists of two parts: one direction walk modeling and two direction walk modeling. The first model aims to determine each channel location by the use of a transition probability with a random walk essentially in the main flow direction, say the north-south direction, while the second model simulates different channels that can be oriented in both directions, either from north to south or from south to north. In both parts of the model, the transition probability is estimated based on two coefficients: one is the correlation coefficient of channel observations; the other is the obstacle coefficient of non-channel observations. A case study with a dense array of 332 wells is presented using the proposed random walk model. For the purpose of model verification, channel maps created by the random walk are compared to the hand-drawn channel maps made by geologists. The results show a good agreement in both types of maps, but in contrast to the single map supplied by geologists, the random walk model is capable of generating many realizations of channel configuration, hence allowing for uncertainty evaluation. A limitation of this approach, related to the influence of the number of wells, is discussed.
Fair, effective, efficient and differentiated scheduling in an enterprise data warehouse
Authors: Chetan Gupta, Abhay Mehta, Song Wang, Umesh Dayal
Venue: Proceedings of the 12th International Conference on Extending Database Technology: Advances in Database Technology (2009)

A typical online Business Intelligence (BI) workload consists of a combination of short, less intensive queries, along with long, resource intensive queries. As such, the longest queries in a typical BI workload may take several orders of magnitude more time to execute, compared with the shortest queries in the workload. This makes it challenging to design a good Mixed Workload Scheduler (MWS). In this paper we first define the design criteria that make a 'good' MWS. We then use these criteria to design rFEED, a MWS that is fair, effective, efficient, and differentiated. We simulate real workloads and compare our rFEED MWS with models of the current best of breed commercial systems. We show that the rFEED MWS works extremely well.
Deep packet inspection comes to the desktop
Authors: Brian O'Higgins
Venue: Proceedings of the 2006 International Conference on Privacy, Security and Trust: Bridge the Gap Between PST Technologies and Business Services (2006)

The perimeter does not go away, it just shrinks to individual hosts. Traditional perimeter security tools such as firewalls, IDS and IPS now migrate to the host, but change along the way. Techniques such as deep packet inspection in particular benefit from Moore's law to a greater extent than other security mechanisms, and will play an increasingly important role in host based security going forward. This talk describes host based IPS progress, and compares and contrasts some of the newer options now available. Deep Packet Inspection technology is discussed in more detail with examples to illustrate how it efficiently shields software vulnerabilities from both known and unknown malware. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Brief paper: Convex invariant sets for discrete-time Lur'e systems
Authors: T. Alamo, A. Cepeda, M. Fiacchini, E. F. Camacho
Venue: Automatica (Journal of IFAC) (2009)

In this paper, a method to estimate the domain of attraction of a class of discrete-time Lur'e systems is presented. A new notion of invariance, denoted LNL-invariance, is introduced. An algorithm to determinate the largest LNL-invariant set for this class of systems is proposed. Moreover, it is proven that the LNL-invariant sets provided by this algorithm are polyhedral convex sets and constitute an estimation of the domain of attraction of the non-linear system. It is shown that any contractive set for the Lur'e system is contained in the LNL-invariant set obtained applying the results of this paper. Two illustrative examples are given.
Statistical estimation of multiple parameters via symbolic dynamic filtering
Authors: Chinmay Rao, Kushal Mukherjee, Soumik Sarkar, Asok Ray
Venue: Signal Processing (2009)

This paper addresses statistical estimation of multiple parameters that may vary simultaneously but slowly relative to the process response in nonlinear dynamical systems. The estimation algorithm is sensor-data-driven and is built upon the concept of symbolic dynamic filtering for real-time execution on limited-memory platforms, such as local nodes in a sensor network. In this approach, the behavior patterns of the dynamical system are compactly generated as quasi-stationary probability vectors associated with the finite-state automata for symbolic dynamic representation. The estimation algorithm is validated on nonlinear electronic circuits that represent externally excited Duffing and unforced van der Pol systems. Confidence intervals are obtained for statistical estimation of two parameters in each of the systems.
A study on impact of aggressor de-rating in the context of multiple crosstalk effects in circuits
Authors: Alodeep Sanyal, Abhisek Pan, Sandip Kundu
Venue: Proceedings of the 19th ACM Great Lakes symposium on VLSI (2009)

Capacitive crosstalk induced signal integrity effects have been studied for over a decade. A typical victim net has multiple aggressors. In worst-case analysis of crosstalk effects, it is customary to assume that (i) all aggressors can switch at the same time and (ii) aggressors themselves are not subject to other crosstalk effects. Further refinements of the worst-case analysis consider (a) Boolean filtering of the aggressors to take logical relationship among them into account and (b) timing filtering to exclude aggressors that cannot switch in the same timing window where the victim node is switching. However, even further refinement is possible by relaxing supposition (ii) above that assumes that aggressors are not subject to noise themselves. In this paper, we present a simulation study that considers multiple crosstalk effects where the aggressors of one net can be victim themselves with signals switching in their neighborhood. The simulations are performed on an innovative compact model that permits circular reasoning in an event-driven, non-zero gate delay, and dynamic simulation framework. Results indicate that when crosstalk on aggressors is also considered while processing crosstalk on a victim, the impact is often mitigated substantially.
Canonical representation of conditionally specified multivariate discrete distributions
Authors: Edward H. Ip, Yuchung J. Wang
Venue: Journal of Multivariate Analysis (2009)

Most work on conditionally specified distributions has focused on approaches that operate on the probability space, and the constraints on the probability space often make the study of their properties challenging. We propose decomposing both the joint and conditional discrete distributions into characterizing sets of canonical interactions, and we prove that certain interactions of a joint distribution are shared with its conditional distributions. This invariance opens the door for checking the compatibility between conditional distributions involving the same set of variables. We formulate necessary and sufficient conditions for the existence and uniqueness of discrete conditional models, and we show how a joint distribution can be easily computed from the pool of interactions collected from the conditional distributions. Hence, the methods can be used to calculate the exact distribution of a Gibbs sampler. Furthermore, issues such as how near compatibility can be reconciled are also discussed. Using mixed parametrization, we show that the proposed approach is based on the canonical parameters, while the conventional approaches are based on the mean parameters. Our advantage is partly due to the invariance that holds only for the canonical parameters.
A Nios II Based English Speech Training System for Hearing-Impaired Children
Authors: Ningfeng Huang, Haining Wu, Yinchen Song
Venue: Proceedings of the 2009 International Conference on Computer Engineering and Technology - Volume 01 (2009)

We propose a novel feature system of language training for hearing-impaired children’s speech rehabilitation based on DE1 development board, which contains an on-chip system called uc/os. The system is imbedded with Nios II processors, which could make our system stable, portable and cheap. Considering the limited storage and calculation ability of imbed system, at the same time, and we recognize child’s voice by Single phoneme, we use LPCC as Eigenvector to judge the similarity between speaker’s voice and example’s.
Auto-recognizing DBMS Workload Based on C5.0 Algorithm
Authors: Zhixian Niu, Lili Zong, Qingwei Yan, Zhenxing Zhao
Venue: Proceedings of the 2009 Second International Workshop on Knowledge Discovery and Data Mining (2009)

The type of the workload is one of the key factors on database management system (DBMS) tuning. Different types of workload (OLTP, Online Transaction Processing and OLAP, Online Analytical Processing) mean different resource allocation strategies. In this paper, we present an approach to automatically identify a DBMS workload as either OLTP or OLAP. We use C5.0 algorithm to construct a set of classifiers based on the characteristics that differentiate OLTP and OLAP and then use the classifier to identify the workload type. The experiments show that the classifiers can be able to accurately identify the OLTP and OLAP workloads.
Study of optimal load lock dedication for cluster tools
Authors: Julie Christopher
Venue: Proceedings of the 40th Conference on Winter Simulation (2008)

Cluster or chamber tools are often used in the semiconductor industry. In a research environment, moving to smaller device dimensions requires experimentation with new chamber types and materials to overcome challenges with Moore's Law. To make the most of expensive mainframes and clean room floor space multiple chamber types can be placed on one mainframe. Although this type of configuration can reduce cost while evaluating new complex processes, the efficiency of the tool as a whole can be drastically reduced. A major bottleneck within tools configured with multiple process chambers can be the load locks. These load locks are the single wafer entry point into the vacuum chamber. This paper will show the effect of load lock dedication on a sample multi-process chamber tool.
Fractional differentiation and non-Pareto multiobjective optimization for image thresholding
Authors: A. Nakib, H. Oulhadj, P. Siarry
Venue: Engineering Applications of Artificial Intelligence (2009)

Various techniques have previously been proposed for single-stage thresholding of images to separate objects from the background. Although these global or local thresholding techniques have proven effective on particular types of images, none of them is able to produce consistently good results on a wide range of existing images. Here, a new image histogram thresholding method, called TDFD, based on digital fractional differentiation is presented for gray-level image thresholding. The proposed method exploits the properties of the digital fractional differentiation and is based on the assumption that the pixel appearance probabilities in the image are related. To select the best fractional differentiation order that corresponds to the best threshold, a new algorithm based on non-Pareto multiobjective optimization is presented. A new geometric regularity criterion is also proposed to select the best thresholded image. In order to illustrate the efficiency of our method, a comparison was performed with five competing methods: the Otsu method, the Kapur method, EM algorithm based method, valley emphasis method, and two-dimensional Tsallis entropy based method. With respect to the mode of visualization, object size and image contrast, the experimental results show that the segmentation method based on fractional differentiation is more robust than the other methods.
Study of 802.11 Network Performance and Wireless Multicasting
Authors: Biju Issac
Venue: Proceedings of the 2009 International Conference on Computer Engineering and Technology - Volume 01 (2009)

IEEE 802.11 proposed a number of standards and each one had a specific goal. They can be configured in infrastructure mode or ad hoc mode. In the study of infrastructure mode, the focus was on 802.11b/g co-existence along with other single mode operations to analyze the throughput and traffic drop through simulation. In the study of ad hoc mode, the focus was to analyze the behavior of ah hoc networks with demand driven ad hoc routing protocols like – Ad-Hoc On-demand Distance Vector Routing, Dynamic Source Routing and Temporally-Ordered Routing Algorithm in terms of throughput. Finally an investigation is done to study wireless multicasting and its behavior.
HEMP-hand-displacement-based pseudo-haptics: A study of a force field application and a behavioural analysis
Authors: Andreas Pusch, Olivier Martin, Sabine Coquillart
Venue: International Journal of Human-Computer Studies (2009)

This paper introduces a novel pseudo-haptic approach called HEMP-Hand-displacEMent-based Pseudo-haptics. The main idea behind HEMP is to provide haptic-like sensations by dynamically displacing the visual representation of the user's hand. This paper studies the possible application of HEMP to the simulation of force fields (FFs). The proposed hardware solution for simulating the hand displacement is based on an augmented reality configuration, the video see-through head-mounted display. A response model is proposed for controlling the hand displacement. This model adapts to the user's hand movements. It also accounts for a number of perceptual and system constraints. An experiment has been carried out to investigate the potential of the proposed technique. Subjects had to perform an FF strength comparison task and to fill in an illusion evaluation questionnaire. Comparison response results show that different FF strength levels are discriminable and the questionnaire indicates that subjects perceive flow pressure-like sensations. The analysis of arm muscular activity seems to confirm these results.