ppxscal/embedding_network huggingface dataset:
On r-locating-dominating sets in paths
Authors: Iiro Honkala
Venue: European Journal of Combinatorics (2009)

Assume that G=(V,E) is a simple undirected graph, and C is a nonempty subset of V. For every vV, we define Ir(v)={uC| dG(u,v)≤r}, where dG(u,v) denotes the number of edges on any shortest path between u and v. If the sets Ir(v) for are pairwise different, and none of them is the empty set, we say that C is an r-locating-dominating set in G. It is shown that the smallest 2-locating-dominating set in a path with n vertices has cardinality [(n+1)/3], which coincides with the lower bound proved earlier by Bertrand, Charon, Hudry and Lobstein. Moreover, we give a general upper bound which improves a result of Bertrand, Charon, Hudry and Lobstein.
Adaptive location updates for mobile sinks in wireless sensor networks
Authors: Guojun Wang, Tian Wang, Weijia Jia, Minyi Guo, Jie Li
Venue: The Journal of Supercomputing (2009)

Mobile sinks can be used to balance energy consumption for sensor nodes in Wireless Sensor Networks (WSNs). Mobile sinks are required to inform sensor nodes about their new location information whenever necessary. However, frequent location updates from mobile sinks can lead to both rapid energy consumption of sensor nodes and increased collisions in wireless transmissions. We propose a new solution with adaptive location updates for mobile sinks to resolve this problem. When a sink moves, it only needs to broadcast its location information within a local area other than among the entire network. Both theoretical analysis and simulation studies show that this solution consumes less energy in each sensor node and also decreases collisions in wireless transmissions, which can be used in large-scale WSNs.
Improving meeting summarization by focusing on user needs: a task-oriented evaluation
Authors: Pei-Yun Hsueh, Johanna D. Moore
Venue: Proceedings of the 13th international conference on Intelligent user interfaces (2009)

Advances in multimedia technologies have enabled the creation of huge archives of audio-video recordings of meetings, and there is burgeoning interest in developing meeting browsers to help users better leverage these archives. A recent study has shown that extractive summaries provide a more efficient way of navigating meeting content than simply reading through the transcript and using the audio-video record, or navigating via keyword search (Murray, 2007). The extractive summary technique identifies informative dialogue acts to generate general purpose summaries. These summaries can still be lengthy. Recently, we have developed a decision-focused summarization system that presents only 1-2% of the recordings related to decision making. In this paper, we describe a task-based evaluation in which we compare the decision-focused summaries to the general purpose summaries. Our results indicate that the more focused summaries help users perform the decision debriefing task more effectively and improve perceived efficiency. In addition, this study also investigates the effect of automatic summaries and transcription on task effectiveness, report quality, and users' perceptions of task success.
Landscape Features, Standards, and Semantics in U.S. National Topographic Mapping Databases
Authors: Dalia Varanka
Venue: Proceedings of the 2009 International Conference on Advanced Geographic Information Systems & Web Services (2009)

The objective of this paper is to examine the contrast between local, field-surveyed topographical representation and feature representation in digital, centralized databases and to clarify their ontological implications. The semantics of these two approaches are contrasted by examining the categorization of features by subject domains inherent to national topographic mapping. When comparing five USGS topographic mapping domain and feature lists, results indicate that multiple semantic meanings and ontology rules were applied to the initial digital database, but were lost as databases became more centralized at national scales, and common semantics were replaced by technological terms. (Abstract)
CG production principles: keeping your money on the screen & off the floor
Authors: Kevin Geiger
Venue: ACM SIGGRAPH ASIA 2008 courses (2008)

How much of your money makes it onto the screen? Got a leaky pipeline? Is your workflow trickling? Does your team approach their work like a film, or like a science project? Are you paying your brain surgeons to dig ditches? Can you roll with last-minute story changes? What economies of scale do you employ? Are you satisfied with your production environment in terms of relationships, communication, adaptation and high-quality delivery?
Brief paper: A duality-based convex optimization approach to L2 -gain control of piecewise affine slab differential inclusions
Authors: Behzad Samadi, Luis Rodrigues
Venue: Automatica (Journal of IFAC) (2009)

This paper introduces the dual parameter set of a piecewise affine (PWA) system. This is a key concept to enable a convex formulation of PWA controller synthesis for PWA slab differential inclusions using a new convex relaxation. Another important contribution of the paper is to present PWA L"2-gain analysis and synthesis results for PWA systems whose output is also a PWA function of the state (as opposed to a piecewise-linear (PWL) function). Unlike other results existing in the literature, the sufficient LMI conditions in this paper are valid for synthesis, even when the PWA systems include sliding modes. A numerical example with sliding modes illustrates the new approach.
An Algorithm and Its Performance Analysis for Ridges Extraction of Time-frequency Distribution Image Using PSO Algorithm
Authors: Ming Yu, Jian Zhao, Jianchao Zeng
Venue: Proceedings of the 2009 WRI International Conference on Communications and Mobile Computing - Volume 01 (2009)

In order to obtain the feature parameters of a signal, the image ridge of time-frequency domain must usually be detected. In the paper, the PSO algorithm is applied to the detection of the transform-domain image ridge. A new ridge detection algorithm is proposed, together with its specific realization process. Furthermore, this method is simulated to evaluate precision of this and the robustness of noise. Comparing its simulation results with the common method prove that this algorithms have the advantage to be fast and simple, with high accuracy, less iterations and small noise. It appears that the so defined ridges deserve as some features of the signal.
An efficient online auditing approach to limit private data disclosure
Authors: Haibing Lu, Yingjiu Li, Vijayalakshmi Atluri, Jaideep Vaidya
Venue: Proceedings of the 12th International Conference on Extending Database Technology: Advances in Database Technology (2009)

In a database system, disclosure of confidential private data may occur if users can put together the answers of past queries. Traditional access control mechanisms cannot guard against such breaches to private data. Online auditing techniques have been advanced to limit such disclosure of private data. Essentially, before answering any query, these techniques inspect the answers of the past queries to determine whether answering this query would compromise the stated data disclosure policies. While the primary requirement for online auditing is high efficiency, existing auditing approaches are expensive with respect to both computational time and space. Specifically, this cost is excessive in the general case of auditing arbitrary aggregate queries over real-valued confidential attributes with respect to interval-based privacy disclosure. In this paper, we model this problem as the well-studied linear programming (LP) problem and propose an efficient online auditing solution for constantly monitoring the bounds of protected attributes. The previously proposed approaches in this direction repetitively employ the LP. Consequently, for each new query, they require evaluation of the entire set of answers to past queries. In this paper, we propose a novel approach to employ LP that keeps the prior evaluation state in a concise form and conducts an incremental evaluation. Basically, our approach treats the online auditing problem as a series of updation problems. Each time when a new query is issued by a user, instead of solving a new LP problem with up-to-date log of all queries, we modify the existing bounds obtained in auditing previous queries based on certain rules so as to get the updated bounds with the new query added. Since it significantly reduces the computation time and storage space, our approach offers the first practical solution for the interval-based online auditing problem. Our experimental results demonstrate that our solution is about 30 times faster than the existing solutions.
Optimal reorder decision-making in the agent-based apparel supply chain
Authors: A. Pan, S. Y. S. Leung, K. L. Moon, K. W. Yeung
Venue: Expert Systems with Applications: An International Journal (2009)

The application of agent technology in the apparel supply chain management has gained increasing interest. Agents can help automate a variety of tasks and facilitate decision-making in the supply chain. Compared with other industries, there are more uncertainties existing in the fashion industry such as market needs, fashion change and seasonality, which increases the difficulty of managing the apparel supply chain especially in the ordering process. Thus, it is necessary to increase the coordination in the apparel supply chain processes and develop optimal decision-making strategy for the apparel supply chain under the dynamic environment. In this paper, unified modeling language (UML) is applied to simulate the supply chain processes and describe the relationships between agents. This paper also applies genetic algorithm (GA) and fuzzy inference theory to the dynamic reorder strategy for the supply chain agent to make optimal decision about replenishment quantity and reorder point in order to minimize the inventory cost correspondingly.
Optimizing multiple queries on scientific datasets with partial replicas
Authors: Li Weng, Umit Catalyurek, Tahsin Kurc, Gagan Agrawal, Joel Saltz
Venue: Proceedings of the 8th IEEE/ACM International Conference on Grid Computing (2007)

We propose strategies to efficiently execute a query workload, which consists of multiple related queries submitted against a scientific dataset, on a distributed-memory system in the presence of partial dataset replicas. Partial replication re-organizes and re-distributes one or more subsets of a dataset across the storage system to reduce I/O overheads and increase I/O parallelism. Our work targets a class of queries, called range queries, in which the query predicate specifies lower and upper bounds on the values of all or a subset of attributes of a dataset. Data elements whose attribute values fall into the specified bounds are retrieved from the dataset. If we think of the attributes of a dataset forming multi-dimensional space, where each attribute corresponds to one of the dimensions, a range query defines a bounding box in this multidimensional space. We evaluate our strategies in two scenarios involving range queries. The first scenario represents the case in which queries have overlapping regions of interest, such as those arising from an exploratory analysis of the dataset by multiple users. In the second scenario, queries represent adjacent rectilinear sections that capture an irregular subregion in the multi-dimensional space. This scenario corresponds to a case where the user wants to query and retrieve a spatial feature from the dataset. We propose cost models and an algorithm for optimizing such queries. Our results using queries for subsetting and analysis of medical image datasets show that effective use of partial replicas can result in reduction in query execution times.
A distributed combustion solver for engine simulations on grids
Authors: Laura Antonelli, Paola Belardini, Pasqua D'Ambra, Francesco Gregoretti, Gennaro Oliva
Venue: Journal of Computational and Applied Mathematics (2009)

Multi-dimensional models for predictive simulations of modern engines are an example of multi-physics and multi-scale mathematical models, since lots of thermofluiddynamic processes in complex geometrical configurations have to be considered. Typical models involve different submodels, including turbulence, spray and combustion models, with different characteristic time scales. The predictive capability of the complete models depends on the accuracy of the submodels as well as on the reliability of the numerical solution algorithms. In this work we propose a multi-solver approach for reliable and efficient solution of the stiff Ordinary Differential Equation (ODE) systems arising from detailed chemical reaction mechanisms for combustion modeling. Main aim was to obtain high-performance parallel solution of combustion submodels in the overall procedure for simulation of engines on distributed heterogeneous computing platforms. To this aim we interfaced our solver with the CHEMKIN-II package and the KIVA3V-II code and carried out multi-computer simulations of realistic engines. Numerical experiments devoted to test reliability of the simulation results and efficiency of the distributed combustion solver are presented and discussed.
Firewall Rule Ordering Based on Statistical Model
Authors: Weiping Wang, Heran Chen, Jiayao Chen, Bowen Liu
Venue: Proceedings of the 2009 International Conference on Computer Engineering and Technology - Volume 02 (2009)

Firewall played an important role as a tool that protects the network of the enterprise. On optimizing firewall policy, firewalls can filter packets effectively and improve the performance of firewalls. Otherwise, if a firewall policy is not written properly, firewall will easily become a fatal point of network attacks. In this paper, we first propose a statistical model that statistic packets which go into or out networks using non-parameter statistic theory. Based on this model, we then propose an algorithm that optimizes the rule ordering of a firewall which can improve the performance of a firewall obviously. We will prove this through our experiment.
Experience evaluation of interactive art: study of GEO landscapes
Authors: Zafer Bilda, Chris Bowman, Ernest Edmonds
Venue: Proceedings of the 5th Australasian Conference on Interactive Entertainment (2008)

The cutting edge in the digital arts is a highly fertile ground for the investigation of engagement and the role of new technologies. The nature of audience interaction with artworks and the implication for the consequential nature of the interactive art system is itself important. This paper examines the process of experience evaluation of interactive art and its role in improving design of interactive art systems. The experience evaluation was based upon the case-study of an interactive artwork entitled GEO Landscapes .01 -- a gallery installation prototype which commenced development in 2006 and was exhibited in a public space in 2007. The experience evaluation study demonstrated how the novice versus expert profiles of interaction behaviours influenced the nature of the artwork experience. The research findings improved our understanding of how people experience artworks and also had an impact on the experience design of GEO Landscapes and the future direction of the project.
Ordered fields and $${{{\rm \L}\Pi\frac{1}{2}}}$$-algebras
Authors: Enrico Marchioni
Venue: Soft Computing - A Fusion of Foundations, Methodologies and Applications (2009)

In this work we further explore the connection between $${{{\rm \L}\Pi\frac{1}{2}}}$$-algebras and ordered fields. We show that any two $${{{\rm \L}\Pi\frac{1}{2}}}$$-chains generate the same variety if and only if they are related to ordered fields that have the same universal theory. This will yield that any $${{{\rm \L}\Pi\frac{1}{2}}}$$-chain generates the whole variety if and only if it contains a subalgebra isomorphic to the $${{{\rm \L}\Pi\frac{1}{2}}}$$-chain of real algebraic numbers, that consequently is the smallest $${{{\rm \L}\Pi\frac{1}{2}}}$$-chain generating the whole variety. We also show that any two different subalgebras of the $${{{\rm \L}\Pi\frac{1}{2}}}$$-chain over the real algebraic numbers generate different varieties. This will be exploited in order to prove that the lattice of subvarieties of $${{{\rm \L}\Pi\frac{1}{2}}}$$-algebras has the cardinality of the continuum. Finally, we will also briefly deal with some model-theoretic properties of $${{{\rm \L}\Pi\frac{1}{2}}}$$-chains related to real closed fields, proving quantifier-elimination and related results.
A weighted multivariate signed-rank test for cluster-correlated data
Authors: Riina Haataja, Denis Larocque, Jaakko Nevalainen, Hannu Oja
Venue: Journal of Multivariate Analysis (2009)

A weighted multivariate signed-rank test is introduced for an analysis of multivariate clustered data. Observations in different clusters may then get different weights. The test provides a robust and efficient alternative to normal theory based methods. Asymptotic theory is developed to find the approximate p-value as well as to calculate the limiting Pitman efficiency of the test. A conditionally distribution-free version of the test is also discussed. The finite-sample behavior of different versions of the test statistic is explored by simulations and the new test is compared to the unweighted and weighted versions of Hotelling's T^2 test and the multivariate spatial sign test introduced in [D. Larocque, J. Nevalainen, H. Oja, A weighted multivariate sign test for cluster-correlated data, Biometrika 94 (2007) 267-283]. Finally, a real data example is used to illustrate the theory.
A comprehensive study of frequency, interference, and training of multiple graphical passwords
Authors: Katherine M. Everitt, Tanya Bragin, James Fogarty, Tadayoshi Kohno
Venue: Proceedings of the 27th international conference on Human factors in computing systems (2009)

Graphical password systems have received significant attention as one potential solution to the need for more usable authentication, but nearly all prior work makes the unrealistic assumption of studying a single password. This paper presents the first study of multiple graphical passwords to systematically examine frequency of access to a graphical password, interference resulting from interleaving access to multiple graphical passwords, and patterns of access while training multiple graphical passwords. We find that all of these factors significantly impact the ease of authenticating using multiple facial graphical passwords. For example, participants who accessed four different graphical passwords per week were ten times more likely to completely fail to authenticate than participants who accessed a single password once per week. Our results underscore the need for more realistic evaluations of the use of multiple graphical passwords, have a number of implications for the adoption of graphical password systems, and provide a new basis for comparing proposed graphical password systems.
The dataflow pointcut: a formal and practical framework
Authors: Dima Alhadidi, Amine Boukhtouta, Nadia Belblidia, Mourad Debbabi, Prabir Bhattacharya
Venue: Proceedings of the 8th ACM international conference on Aspect-oriented software development (2009)

Some security concerns are sensitive to flow of information in a program execution. The dataflow pointcut has been proposed by Masuhara and Kawauchi in order to easily implement such security concerns in aspect-oriented programming (AOP) languages. The pointcut identifies join points based on the origins of values. This paper presents a formal framework for this pointcut based on the λ_calculus. Dataflow tags are propagated statically to track data dependencies between expressions. We introduce a static semantics for tag propagation and prove that it is consistent with respect to the dynamic semantics of the propagation. We instrument the static effect-based type system to propagate tags, match and inject advices. This static approach can be used to minimize the cost of dataflow pointcuts by reducing the runtime overhead since much of the dataflow information would be available statically and at the same time it can be used for verification. The proposed semantics for advice weaving is in the spirit of AspectJ where advices are injected before, after, or around the join points that are matched by their respective pointcuts. Inspired from the formal framework, the AspectJ compiler ajc is extended with the dataflow pointcut that tracks data dependencies inside methods.
Dynamic Window-Constrained Scheduling for Multimedia Applications
Authors: Richard West, Karsten Schwan
Venue: Proceedings of the 1999 IEEE International Conference on Multimedia Computing and Systems - Volume 02 (1999)

This paper describes an algorithm, called Dynamic Window-Constrained Scheduling (DWCS), designed to meet the service constraints on packets from multiple, network-bound media streams with different performance objectives. Using only two attributes, a deadline and a loss-tolerance per packet stream, DWCS: (1) can limit the number of late packets over finite numbers of consecutive packets in loss-tolerant or delay-constrained, heterogeneous traffic streams, (2) does not require a-priori knowledge of the worst-case loading from multiple streams to establish the necessary bandwidth allocations to meet per-stream delay and loss-constraints, and (3) can exhibit both fairness and unfairness properties when necessary. In fact, DWCS can perform fair-bandwidth allocation, static priority (SP) and earliest-deadline first (EDF) scheduling. We show the effectiveness of DWCS using a streaming video application, running over ATM.
Enhancing the reliability of ad-hoc networks through fuzzy trust evaluation
Authors: H. Hallani, S. A. Shahrestani
Venue: Proceedings of the 8th conference on Applied computer scince (2008)

Ideally, in Ad-hoc networks all comprising nodes act cooperatively in establishing the communication paths from various sources to destinations. However, in practice such an ideal situation may not always be realized. Some nodes may act selfishly, refusing to accept the burden of forwarding packets. Some other nodes may act maliciously. Either way, such nodes degrade the network reliability or even disrupt its operation altogether. To alleviate the problems caused by the presence of such nodes, this paper proposes to establish quantifiable trust levels for the comprising nodes and to use them in making routing decisions. The proposed approach uses fuzzy logic concepts in evaluating the trust levels of the nodes. The trust levels are then used in the routing process. Using OPNET and MATLAB, the proposed approach is validated and further analyzed. It is shown that the utilization of this approach can result in significant enhancements of the performance and reliability of Ad-hoc networks.