ppxscal/embedding_network huggingface dataset:
Fixation-identification in dynamic scenes: comparing an automated algorithm to manual coding
Authors: Susan M. Munn, Leanne Stefano, Jeff B. Pelz
Venue: Proceedings of the 5th symposium on Applied perception in graphics and visualization (2008)

Video-based eye trackers produce an output video showing where a subject is looking, the subject's point-of-regard (POR), for each frame of a video of the scene. Fixation-identification algorithms simplify the long list of POR data into a more manageable set of data, especially for further analysis, by grouping PORs into fixations. Most current fixation-identification algorithms assume that the POR data are defined in static two-dimensional scene images and only use these raw POR data to identify fixations. The applicability of these algorithms to gaze data in dynamic scene videos is largely unexplored. We implemented a simple velocity-based, duration-sensitive fixation-identification algorithm and compared its performance to results obtained by three experienced users manually coding the eye tracking data displayed within the scene video such that these manual coders had knowledge of the scene motion. We performed this comparison for eye tracking data collected during two different tasks involving different types of scene motion. These two tasks included a subject walking around a building for about 100 seconds (Task 1) and a seated subject viewing a computer animation (approximately 90 seconds long, Task 2). It took our manual coders on average 75 minutes (stdev = 28) and 80 minutes (17) to code results from the first and second tasks, respectively. The automatic fixation-identification algorithm, implemented in MATLAB and run on an Apple 2.16 GHz MacBook, produced results in 0.26 seconds for Task 1 and 0.21 seconds for Task 2. For the first task (walking), the average percent difference among the three human manual coders was 9% (3.5) and the average percent difference between the automatically generated results and the three coders was 11% (2.0). For the second task (animation), the average percent difference among the three human coders was 4% (0.75) and the average percent difference between the automatically generated results and the three coders was 5% (0.9).
Efficient solutions to a class of generalized time-dependent combinatorial optimization problems
Authors: Todd W. Kolb, Lixin Tao, Michael W. Tao
Venue: Proceedings of the 7th WSEAS International Conference on Applied Mathematics (2005)

A class of generalized intractable time-dependent problems is identified and abstracted into a mathematical model. Simulated annealing is adopted as the base of the solution strategy. Comprehensive experiments are conducted to study the sensitivity of the algorithm to the values of its multiple parameters. Extensive performance evaluation shows that the proposed algorithm significantly outperforms the best published alternative algorithms for the same problem class.
Integrating and querying distributed XML data via XLink
Authors: Wolfgang May, Erik Behrends, Oliver Fritzen
Venue: Information Systems (2008)

XML instances are not necessarily self-contained but may have connections to remote XML data residing on other servers. In this paper, we show that-in spite of its minor support and use in the XML world-the XLink language provides a powerful mechanism for expressing such links both from the modeling point of view and for actually querying interlinked XML data: in our dbxlink approach, the links are not seen as explicit links (where the users must be aware of the links and traverse them explicitly in their queries), but define views that combine into a logical, transparent XML model which serves as an external schema and can be queried by XPath/XQuery. We motivate the underlying modeling and give a concise and declarative specification as an XML-to-XML mapping. We also describe the implementation of the model as an extension of the eXist [eXist: an Open Source Native XML Database, http://exist-db.org/] XML database system. The approach can be applied both for distribution of data and for integration of data from autonomous sources.
Generalized synthesis for singular nonlinear optimal control problems
Authors: M. Guerra
Venue: Automation and Remote Control (2008)

We consider the problem of minimizing a quadratic noncoercive functional along the trajectories of a control-affine system. Due to lack of coercivity, existence of "classical" minimizers cannot, in general, be guaranteed. Under appropriate commutativity assumptions the problem can be extended into the space of generalized controls of class W ¿1,¿ and reduced into a new problem which is generically coercive but nonconvex. We show how to extend further the problem in order to include generalized controls which are "generalized derivatives of one-parameter families of regular probability measures," thus achieving convexification. Generalized trajectories for this type of controls exist only in a weak sense. We discuss a version of the maximum principle suitable to this class of problems and show how a generalized synthesis can be obtained.
Signal Processing Based for Fetal Electrocardiogram Extraction
Authors: Saman Sargolzaei, Karim Faez, Arman Sargolzaei
Venue: Proceedings of the 2008 International Conference on BioMedical Engineering and Informatics - Volume 02 (2008)

In this paper, we describe four important indirect methods which be used to extract the Fetal Electrocardiogram (FECG) signal from an ECG recorded on the mother’s abdomen. These methods include the following ones: Singular Value Decomposition (SVD) method, IndependentComponent Analysis (ICA) method, Wavelet Based methods and Adaptive Filtering method. The mentioned methods use signal processing techniques for extracting FECG from Abdominal Electrocardiogram (AECG). We have explainedadvantages and disadvantages of each method. The methods have also applied on both synthetic and real ECG signals. Efficiencies of the methods compared together based on three important criterions and results are stated and best method based on three criterions is selected.
Wide Diameter of Cayley Digraphs of Finite Cyclic Groups
Authors: Xingde Jia
Venue: Proceedings of the The International Symposium on Parallel Architectures, Algorithms, and Networks (2008)

According to recent studies, communication networks built on extremal Cayley digraphs of finite cyclic groups have many advantages over that based on n-cubes. Extremal Cayley digraphs have been studied extensively in recent years. In this paper, we prove, for every positive integer k, that the k-wide diameter of the Cayley diagraph Cay(Zm,A) is at most diam(Cay(Zm,A)) + 1 if A is an "m-ideal" set of k positive integers.
Efficient computation of sum-products on GPUs through software-managed cache
Authors: Mark Silberstein, Assaf Schuster, Dan Geiger, Anjul Patney, John D. Owens
Venue: Proceedings of the 22nd annual international conference on Supercomputing (2008)

We present a technique for designing memory-bound algorithms with high data reuse on Graphics Processing Units (GPUs) equipped with close-to-ALU software-managed memory. The approach is based on the efficient use of this memory through the implementation of a software-managed cache. We also present an analytical model for performance analysis of such algorithms. We apply this technique to the implementation of the GPU-based solver of the sum-product or marginalize a product of functions (MPF) problem, which arises in a wide variety of real-life applications in artificial intelligence, statistics, image processing, and digital communications. Our motivation to accelerate MPF originated in the context of the analysis of genetic diseases, which in some cases requires years to complete on modern CPUs. Computing MPF is similar to computing the chain matrix product of multi-dimensional matrices, but is more difficult due to a complex data-dependent access pattern, high data reuse, and a low compute-to-memory access ratio. Our GPU-based MPF solver achieves up to 2700-fold speedup on random data and 270-fold on real-life genetic analysis datasets on GeForce 8800GTX GPU from NVIDIA over the optimized CPU version on an Intel 2.4GHz Core 2 with a 4MB L2 cache.
Information Agents for Pervasive Sensor Networks
Authors: Alex Rogers, Mike Osborne, Sarvapali D. Ramchurn, Stephen Roberts, Nicholas R. Jennings
Venue: Proceedings of the 2008 Sixth Annual IEEE International Conference on Pervasive Computing and Communications (2008)

In this paper, we describe an information agent, that resides on a mobile computer or personal digital assistant(PDA), that can autonomously acquire sensor readings from pervasive sensor networks (deciding when and which sensor to acquire readings from at any time). Moreover, it can perform a range of information processing tasks including modelling the accuracy of the sensor readings, predicting the value of missing sensor readings, and predicting how the monitored environmental parameters will evolve into the future. Our motivating scenario is the need to provide situational awareness support to first responders at the scene of a large scale incident, and we describe how we use an iterative formulation of a multi-output Gaussian process to build a probabilistic model of the environmental parameters being measured by local sensors, and the correlations and delays that exist between them. We validate our approach using data collected from a network of weather sensors located on the south coast of England.
Exploring a digital library through key ideas
Authors: Bill N. Schilit, Okan Kolak
Venue: Proceedings of the 8th ACM/IEEE-CS joint conference on Digital libraries (2008)

Key Ideas is a technique for exploring digital libraries by navigating passages that repeat across multiple books. From these popular passages emerge quotations that authors have copied from book to book because they capture an idea particularly well: Jefferson on liberty; Stanton on women's rights; and Gibson on cyberpunk. We augment Popular Passages by extracting key terms from the surrounding context and computing sets of related key terms. We then create an interaction model where readers fluidly explore the library by viewing popular quotations on a particular key term, and follow links to quotations on related key terms. In this paper we describe our vision and motivation for Key Ideas, present an implementation running over a massive, real-world digital library consisting of over a million scanned books, and describe some of the technical and design challenges. The principal contribution of this paper is the interaction model and prototype system for browsing digital libraries of books using key terms extracted from the aggregate context of popularly quoted passages.
Predicting Blood-Brain Barrier Penetration by Stochastic Discrimination
Authors: Dechang Chen, Jianwen Fang, Jiawei Yu
Venue: Proceedings of the 2008 International Conference on BioMedical Engineering and Informatics - Volume 01 (2008)

The importance of optimizing the ability to penetrate blood-brain barrier of potential drug candidates is now widely recognized. Accurate computational prediction of such a property will significantly enhance the speed of the blood-brain barrier penetration analysis and reduce the cost of drug discovery. In this paper, we present some results of our predictive model built on the stochastic discrimination, a pattern classification method that has been shown to be a useful in the literature.
Diameters, centers, and approximating trees of delta-hyperbolicgeodesic spaces and graphs
Authors: Victor Chepoi, Feodor Dragan, Bertrand Estellon, Michel Habib, Yann Vaxès
Venue: Proceedings of the twenty-fourth annual symposium on Computational geometry (2008)

δ-Hyperbolic metric spaces have been defined by M. Gromov via a simple 4-point condition: for any four points u,v,w,x, the two larger of the sums d(u,v)+d(w,x), d(u,w)+d(v,x), d(u,x)+d(v,w) differ by at most 2δ. Given a finite set S of points of a δ-hyperbolic space, we present simple and fast methods for approximating the diameter of S with an additive error 2δ and computing an approximate radius and center of a smallest enclosing ball for S with an additive error 3δ. These algorithms run in linear time for classical hyperbolic spaces and for δ-hyperbolic graphs and networks. Furthermore, we show that for δ-hyperbolic graphs G=(V,E) with uniformly bounded degrees of vertices, the exact center of S can be computed in linear time O(|E|). We also provide a simple construction of distance approximating trees of δ-hyperbolic graphs G on n vertices with an additive error O(δlog2 n). This construction has an additive error comparable with that given by Gromov for n-point δ-hyperbolic spaces, but can be implemented in O(|E|) time (instead of O(n2)). Finally, we establish that several geometrical classes of graphs have bounded hyperbolicity.
Formalization of Link Farm Structure Using Graph Grammar
Authors: Kiattikun Chobtham, Athasit Surarerks, Arnon Rungsawang
Venue: Proceedings of the 22nd International Conference on Advanced Information Networking and Applications (2008)

A link farm is a set of web pages constructed to mislead the importance of target pages in search engine results by boosting their link-based ranking scores. In this paper, we introduce a new graph grammar model for expressing the structure of a link farm. Supervised graph grammar induction created by an expert is modified to fit the training data to explain the behavior and the properties of link farms. In the experiments, graph grammar can effectively recognize link farms from Yahoo’s web spam dataset. The comparison among the number of applying production rules of spam and normal hosts indicates that graph grammar seem to be a good mechanism for detecting link spam.
On Safe Service-Oriented Real-Time Coordination for Autonomous Vehicles
Authors: Basil Becker, Holger Giese
Venue: Proceedings of the 2008 11th IEEE Symposium on Object Oriented Real-Time Distributed Computing (2008)

The performance of autonomous vehicles could be drastically improved if ad-hoc networking and suitable real-time coordination is employed to optimize and improve the joint behavior of multiple autonomous units. However, due to ad-hoc connections and the real-time interaction the correctness and safety of such coordinated autonomous units is very hard to ensure. In this paper we present how service-oriented real-time coordination can be employed to achieve this goal. Based on the proper real-time coordination between two or more vehicles captured by a service contract, we focus on structural changes and the instantiation and termination of service contracts which is a crucial prerequisite for a safe system operation. We present how the structural changes and the service contract creation/deletion can be modeled by a well-defined UML subset consisting of class and object diagrams with collaborations as well as well-defined behavioral rules can be verified taking the dynamic structural changes due to the ad-hoc networking as well as the real-time coordination into account. The new verification technique is outlined and the application of the technique for an application example is presented.
Ad hoc networks beyond unit disk graphs
Authors: Fabian Kuhn, Roger Wattenhofer, Aaron Zollinger
Venue: Wireless Networks (2008)

In this paper, we study an algorithmic model for wireless ad hoc and sensor networks that aims to be sufficiently close to reality as to represent practical real-world networks while at the same time being concise enough to promote strong theoretical results. The quasi unit disk graph model contains all edges shorter than a parameter d between 0 and 1 and no edges longer than 1. We show that--in comparison to the cost known for unit disk graphs--the complexity results of geographic routing in this model contain the additional factor 1/d2. We prove that in quasi unit disk graphs flooding is an asymptotically message-optimal routing technique, we provide a geographic routing algorithm being most efficient in dense networks, and we show that classic geographic routing is possible with the same asymptotic performance guarantees as for unit disk graphs if d ≥ 1/√2.
Discovering gis sources on the web using summaries
Authors: Ramaswamy Hariharan, Bijit Hore, Sharad Mehrotra
Venue: Proceedings of the 8th ACM/IEEE-CS joint conference on Digital libraries (2008)

In this paper, we consider the problem of discovering GIS data sources on the web. Source discovery queries for GIS data are specified using keywords and a region of interest. A source is considered relevant if it contains data that matches the keywords in the specified region. Existing techniques simply rely on textual metadata accompanying such datasets to compute relevance to user-queries. Such approaches result in poor search results, often missing the most relevant sources on the web. We address this problem by developing more meaningful summaries of GIS datasets that preserve the spatial distribution of keywords. We conduct experiments showing the effectiveness of proposed summarization techniques by significantly improving the quality of query results over baseline approaches, while guaranteeing scalability and high performance.
A novel pressure sensor with a PDMS diaphragm
Authors: Dong-Weon Lee, Young-Soo Choi
Venue: Microelectronic Engineering (2008)

This paper describes a novel pressure sensor with a polydimethylsiloxane (PDMS) diaphragm, which is used to achieve much larger deformation than conventional silicon diaphragms under low pressure. The larger deformation of the PDMS diaphragm provides higher sensitivity than silicon-based pressure sensors because of the lower Young's modulus of the PDMS diaphragm. The great advantage of the PDMS diaphragm with respect to sensitivity was confirmed through the use of the numerical simulation method and through the conduct of basic experiments. A carbon fibre 10@mm in diameter was used to sense the strain change that had been induced on the diaphragm during its operation. The optimal position of the carbon fibre in the PDMS diaphragm was determined using the numerical analysis method. The carbon fibre was exactly formed across the Al electrodes in the diaphragm through dielectrophoresis. The replacement of the piezoresistor material provided some advantages, such as easy fabrication and a high gauge factor. Several types of pressure sensors with a PDMS diaphragm were fabricated, and the feasibility of such pressure sensors was evaluated.
Solving real school timetabling problems with meta-heuristics
Authors: F. Melício, P. Caldeira, A. Rosa
Venue: Proceedings of the 4th WSEAS International Conference on Applied Mathematics and Computer Science (2005)

School timetabling is a classical combinatorial optimization problem, which consists in assigning lessons to time slots, satisfying a set of constraints of various kinds. Due mostly to the constraints this problem falls in the category of NP-Complete problems. In this paper we try to show an implementation of a decision support system that solves real timetabling problems from various schools in Portugal. This implementation is based on the Simulated Annealing meta-heuristic. The constraints we use were obtained after inquiries made to several schools in Portugal. We show the results on three schools from different levels of teaching.
A deterministic view of random sampling and its use in geometry
Authors: B. Chazelle, J. Friedman
Venue: Proceedings of the 29th Annual Symposium on Foundations of Computer Science (1988)

A number of efficient probabilistic algorithms based on the combination of divide-and-conquer and random sampling have been recently discovered. It is shown that all those algorithms can be derandomized with only polynomial overhead. In the process. results of independent interest concerning the covering of hypergraphs are established, and various probabilistic bounds in geometry complexity are improved. For example, given n hyperplanes in d-space and any large enough integer r, it is shown how to compute, in polynomial time, a simplicial packing of size O(r/sup d/) that covers d-space, each of whose simplices intersects O(n/r) hyperplanes. It is also shown how to locate a point among n hyperplanes in d-space in O(log n) query time, using O(n/sup d/) storage and polynomial preprocessing.
A graph approach to the threshold all-against-all substring matching problem
Authors: Marina Barsky, Ulrike Stege, Alex Thomo, Chris Upton
Venue: Journal of Experimental Algorithmics (JEA) (2008)

We present a novel graph model and an efficient algorithm for solving the &ldquo;threshold all against all&rdquo; problem, which involves searching two strings (with length M and N, respectively) for all maximal approximate substring matches of length at least S, with up to K differences. Our algorithm solves the problem in time O(MNK3), which is a considerable improvement over the previous known bound for this problem. We also provide experimental evidence that, in practice, our algorithm exhibits a better performance than its worst-case running time.
The Fraud Act 2006: The E-Crime Prosecutor's Champion or the Creator of a New Inchoate Offence?
Authors: Maureen Johnson, Kevin M. Rogers
Venue: International Review of Law, Computers and Technology (2007)

After a considerable gestation period, the Fraud Act 2006 came into force on 15th January 2007. The introduction of general offences is intended to provide scope to ensure that technologically focused crime can be targeted. However, whilst the sentiments behind the new Act are to be welcomed, it is argued that there are a number of deficiencies in the new Act, which could lead to considerable problems. First, although the Act shifts focus away from deception problems (notably that deception of a machine or computer is not legally possible) it moves towards the concept of dishonesty, which is problematic in itself as there already exists a number of criticisms relating to this concept. Second, there are problems with a failure of the Act to provide for specific definitions of key concepts, such as 'fraud', 'false' or 'abuse'. Third, and arguably most importantly, under the new Act the liability-threshold for fraud shifts; fraud is no longer a result crime, but a conduct crime. This has the advantage of the law stepping in at an early stage to prevent further criminality; although at the same time potentially provides a completely new concept of the criminal act of fraud.
An Accomplished Simulator for Discrete Event Systems
Authors: Jih-Fu Tu
Venue: Proceedings of the 2008 Second Asia International Conference on Modelling & Simulation (AMS) (2008)

In this paper, we accomplished a simulator, which can be used to model the discrete event systems. This accomplished simulator is implemented based on the Petri net theory, and the transaction of Petri net is done by fuzzy inference. To verify this implemented simulation tool is a feasible, and use it to simulate a washing machine. The simulator is developed by Virus Basic 7.0, and executed in Windows platforms. The contribution of this paper has friendly user interface and graphical icon to create model. Now, this simulator is implemented with the traditional Chinese version and it graphic user interface (GUI), too.
Moda - multiple objective decision analysis: balancing quality attributes in software architectures
Authors: Lihua Xu
Venue: Companion of the 30th international conference on Software engineering (2008)

A high-quality software architecture facilitates in developing a high quality software-intensive system. To design such architecture, the architect must consider multiple stakeholders' inconsistent, contradictory, and partially understood objectives, and balance the myriad tradeoffs among them. Our approach proposes to balance quality attributes in software architectures by identify the important-yet-to-be-addressed quality attributes during the design process and provide architecture analysis methods to help compare the resulting architecture candidates with respect to required quality attributes.