ppxscal/embedding_network huggingface dataset:
A New Image Scaling Algorithm Based on the Sampling Theorem of Papoulis and Application to Color Images
Authors: Alain Hore, Djemel Ziou, Francois Deschenes
Venue: Proceedings of the Fourth International Conference on Image and Graphics (2007)

We present in this paper a new image scaling algorithm which is based on the generalized sampling theorem of Papoulis. The main idea consists in using the first and second derivatives of an image in the scaling process. The derivatives contain information about edges and discontinuities that should be preserved during resizing. The sampling theorem of Papoulis is used to combine this information. We compare our algorithm with nine of the most common scaling algorithms and two measures of quality are used: the standard deviation for evaluation of the blur, and the curvature for evaluation of the aliasing. The results presented here show that our algorithm gives the best images with very few aliasing, good contrast, good edge preserving and few blur. We also present how our algorithm applies to color images.
Automatic Patch Generation for Buffer Overflow Attacks
Authors: Alexey Smirnov, Tzi-cker Chiueh
Venue: Proceedings of the Third International Symposium on Information Assurance and Security (2007)

Control-hijacking attacks exploit vulnerabilities in network services to take control of them and eventually their underlying machines. Although much work has been done on detection and prevention of control-hijacking attacks, most of them did not address the problem of repairing the attacked network services so as to prevent the same attacks from recurring. Ideally, post-attack repair should consist of an attack signature generation component that creates a filtering rule for front-end firewall or intrusion prevention system to block the detected attack and its variants, and a patch generation component that creates a fix to permanently eliminate the vulnerabilities that the detected attack exploits. This paper describes the design, implementation and evaluation of a program transformation and execution trace analysis system called PASAN that can automatically instrument the source code of network service programs in such a way that it can detect control-hijacking attacks and automatically generate patches to seal the vulnerability being exploited by the detected attack. We have implemented the first PASAN prototype as a GNU C compiler extension that aims at stackbased buffer overflow attacks but could be easily generalized to accommodate other control-hijacking attacks. Testing this prototype with seven network daemon programs with known vulnerabilities show that the automatically generated patches can successfully fix the vulnerability. In addition, these patches are similar in their structure to those that are manually created. The run-time performance overhead of application programs instrumented by PASAN is between 10% and 23%, except two programs, whose CPU consumption is low.
Interpretable Granulation of Medical Data with DC
Authors: Corrado Mencar, Arianna Consiglio, Anna Maria Fanelli
Venue: Proceedings of the 7th International Conference on Hybrid Intelligent Systems (2007)

In this paper we describe an approach for mining interpretable diagnostic rules through a fuzzy information granulation process. Specifically, this process is performed by the DC* algorithm (Double Clustering with A*), which is aimed at mining from data a set of fuzzy information granules that satisfy a number of interpretability constraints. Such granules can be labelled with linguistic terms and used as building blocks for deriving diagnostic rules. The DC* is based on two clustering steps. The first step applies the LVQ1 algorithm to find a number of prototypes in the input space, which represent hidden relationships among data. The second clustering step .based on the A* search. takes place on the projections of such prototypes, and is aimed at finding an optimal number of granules that verify interpretability constraints. The application of DC* to two well-known medical datasets provided a set of intelligible rules with satisfactory accuracy.
Graphs with Large Girth Not Embeddable in the Sphere
Authors: Pierre Charbit, Stephan Thomasse
Venue: Combinatorics, Probability and Computing (2007)

In 1972, Rosenfeld asked if every triangle-free graph could be embedded in the unit sphere Sd in such a way that two vertices joined by an edge have distance more than &radic;3(ie, distance more than 2&pi;/3 on the sphere). In 1978, Larman [LAR] disproved this conjecture, constructing a triangle-free graph for which the minimum length of an edge could not exceed &radic;8/3. In addition, he conjectured that the right answer would be &radic;2, which is not better than the class of all graphs. Larman'sconjecture was independently proved by Rosenfeld [MR] and R&ouml;dl [VR[. In this last paper it was shown that no bound better than &radic;2 can be found for graphs with arbitrarily large odd girth. We prove in this paper that this is stilltrue for arbitrarily large girth. We discuss then the case of triangle-free graphs with linear minimum degree.
Retrieval of Handwritten Lines in Historical Documents
Authors: L. Schomaker
Venue: Proceedings of the Ninth International Conference on Document Analysis and Recognition - Volume 02 (2007)

This study describes methods for the retrieval of handwritten lines of text in a historical administrative collection. The goal is to develop generic methods for bootstrapping the retrieval system from a tabula rasa starting condition, i.e., the virtual absence of labeled samples. By exploiting the currently available computing power and the fact that computation takes place off line, it should be possible to provide a good starting point for statistical learning methods. In this manner, a closed collection can be incrementally indexed. A cross- correlation method on line-strip images is presented and results are compared to feature-based methods.
A parametrized algorithm that implements sequential, causal, and cache memory consistencies
Authors: Ernesto Jiménez, Antonio Fernández, Vicent Cholvi
Venue: Journal of Systems and Software (2008)

In this paper, we present an algorithm that can be used to implement sequential, causal, or cache consistency in distributed shared memory (DSM) systems. For this purpose it includes a parameter that allows us to choose the consistency model to be implemented. If all processes run the algorithm with the same value in this parameter, the corresponding consistency is achieved. (Additionally, the algorithm tolerates that processes use certain combination of parameter values.) This characteristic allows a concrete consistency model to be chosen, but implements it with the more efficient algorithm in each case (depending of the requirements of the applications). Additionally, as far as we know, this is the first algorithm proposed that implements cache coherence. In our algorithm, all the read and write operations are executed locally when implementing causal and cache consistency (i.e., they are fast). It is known that no sequential algorithm has only fast memory operations. In our algorithm, however, all the write operations and some read operations are fast when implementing sequential consistency. The algorithm uses propagation and full replication, where the values written by a process are propagated to the rest of the processes. It works in a cyclic turn fashion, with each process of the DSM system, broadcasting one message in turn. The values written by the process are sent in the message (instead of sending one message for each write operation): However, unnecessary values are excluded. All this permits the amount of message traffic owing to the algorithm to be controlled.
Assessing an ambulance service with queuing theory
Authors: Marcos Singer, Patricio Donoso
Venue: Computers and Operations Research (2008)

We describe an ambulance service in terms of its main operation parameters and strategic decision variables. Assisted by queuing theory, we calculate the key performance indicators (KPI) that concern the manager and the KPI that concern the patient. We use them to improve the operation of a private ambulance service in Chile. First, we evaluate whether the historical performance is consistent with the resources deployed. Then, we estimate the impact of some operational enhancements, such as reducing the cycle time or enlarging the fleet. Finally, we optimize the geographical coverage of the bases. We conclude that simple mathematical expressions are very useful to evaluate and improve the operation.
The LBF R-tree: Efficient Multidimensional Indexing with Graceful Degradation
Authors: Todd Eavis, David Cueva
Venue: Proceedings of the 11th International Database Engineering and Applications Symposium (2007)

In multi-dimensional database environments, we typically require effective indexing mechanisms for all but the smallest data sets. While numerous such methods have been proposed, the R-tree has emerged as one of the most common and reliable indexing models. Nevertheless, as user queries grow in terms of both size and dimensionality, R-tree performance can deteriorate significantly. In some application areas, however, it is possible to exploit data and query specific features to obtain dramatic improvements in query performance. We propose a variation of the classic R-tree that specifically targets data warehousing architectures. The new model not only improves performance on common user-defined range queries, but gracefully degrades to a linear scan of the data on pathologically large queries. Experimental results demonstrate reductions in disk seeks of more than 50% relative to more conventional R-tree designs.
Cores of Swirling Particle Motion in Unsteady Flows
Authors: Tino Weinkauf Jan Sahner Holger Theisel Hans-Christian Hege
Venue: IEEE Transactions on Visualization and Computer Graphics (2007)

In nature and in flow experiments particles form patterns of swirling motion in certain locations. Existing approaches identify these structures by considering the behavior of stream lines. However, in unsteady flows particle motion is described by path lines which generally gives different swirling patterns than stream lines. We introduce a novel mathematical characterization of swirling motion cores in unsteady flows by generalizing the approach of Sujudi/Haimes to path lines. The cores of swirling particle motion are lines sweeping over time, i.e., surfaces in the space-time domain. They occur at locations where three derived 4D vectors become coplanar. To extract them, we show how to re-formulate the problem using the Parallel Vectors operator. We apply our method to a number of unsteady flow fields.
A Model for Obstacles to be used in Simulations of Wireless Sensor Networks and its Application in studying Routing Protocol Performance
Authors: Ioannis Chatzigiannakis, Georgios Mylonas, Sotiris Nikoletseas
Venue: Simulation (2007)

We propose a simple obstacle model to be used while simulating wireless sensor networks. To the best of our knowledge, this is the first time such an integrated and systematic obstacle model for these networks has been proposed. We define several types of obstacles that can be found inside the deployment area of a wireless sensor network and provide a categorization of these obstacles based on their nature (physical and communication obstacles, i.e. obstacles that are formed out of node distribution patterns or have physical presence, respectively), their shape and their change of nature over time. We make an eXtension to a custom-made sensor network simulator (simDust) and conduct a number of simulations in order to study the effect of obstacles on the performance of some representative (in terms of their logic) data propagation protocols for wireless sensor networks. Our findings confirm that obstacle presence has a significant impact on protocol performance, and also that different obstacle shapes and sizes may affect each protocol in different ways. This provides an insight into how a routing protocol will perform in the presence of obstacles and highlights possible protocol shortcomings. Moreover, our results show that the effect of obstacles is not directly related to the density of a sensor network, and cannot be emulated only by changing the network density.
A Decision Tree-Based Approach to Mining the Rules of Concept Drift
Authors: Chien-I Lee, Cheng-Jung Tsai, Jhe-Hao Wu, Wei-Pang Yang
Venue: Proceedings of the Fourth International Conference on Fuzzy Systems and Knowledge Discovery - Volume 04 (2007)

In a database, the concept of an example might change along with time, which is known as concept drift. When the concept drift occurs, the classification model built by using old dataset is not suitable for predicting new coming dataset. Although many algorithms had been proposed to solve this problem, they focus only on updating the classification model. However, in a real life users might be very interested in the rules of concept drift. For example, doctors would desire to know the main causes more for disease variation since such rules would enable them to diagnose patients more correctly and quickly. In this paper, we propose a Concept Drift Rule mining Tree to accurately discover the rule of concept drift. The main contributions of this paper are: a) we address the problem of mining concept-drifting rule which was ignored in the past; b) our method can accurately mine the rule of concept drift.
A modified 4-point bend delamination test
Authors: Bo Wang, T. Siegmund
Venue: Microelectronic Engineering (2008)

The 4-point bend delamination test is widely used to study the adhesive properties in thin film structures. The analysis of such tests is commonly based on assumption that symmetry conditions are appropriate to describe crack length and loading. These conditions are, however, rarely fulfilled, and it is common that only a single crack is being propagated. This fact is especially of concern in fatigue crack growth studies. Solutions for energy release rates for asymmetric 4-point bend delamination specimens are presented. A semi-articulated test fixture is described. The experiments conducted with this fixture and the additional energy release rate equations allow that cracks to both sides of the specimen are being propagated. In toughness testing this provides two values for the critical energy release rate from a single test. In fatigue testing, it is demonstrated that near symmetric crack growth was obtained, and remaining asymmetry effects can be quantified.
A New Architecture Description Language for Service-Oriented Architec
Authors: Xiangyang Jia, Shi Ying, Tao Zhang, Honghua Cao, Dan Xie
Venue: Proceedings of the Sixth International Conference on Grid and Cooperative Computing (2007)

Service Oriented Architecture (SOA) is a new form of distributed software architecture. In SOA, the coarse-grained, discoverable, loosely coupled, autonomous services are its basic constitutional units. This makes the SOA different from other architectures for its special architecture elements (services) and its dynamic and evolving structure. How to model this specific architecture and support service-oriented development is an important research field in service-oriented software engineering community. Present modeling technologies for service and SOA tend to be technology-aligned, and the works that try to model and analyze the service and SOA in a higher and more abstract level are relatively rare. This paper proposes SOADL, a new architecture description language for SOA. SOADL specifies the interfaces, behavior, Semantics and quality properties of services, provides mechanisms to model and analyze the dynamic and evolving architecture, and supports architecture-based service composition.
Minimum Error Discriminative Training for Radical-Based Online Chinese Handwriting Recognition
Authors: Y. Zhang, P. Liu, F. Soong
Venue: Proceedings of the Ninth International Conference on Document Analysis and Recognition - Volume 01 (2007)

Free style Chinese handwriting recognition continues to pose a challenge to researchers due to the variety of writing styles. To recognize handwritten characters in an online mode, Hidden Markov Model (HMM) has been naturally adopted to model the pen trajectory of a character and a de- cent recognition performance is achieved. In this study, we start from a maximum likelihood trained HMM model and focus on minimizing recognition errors at the radical (sub- character) level to optimize the recognition performance. A novel Minimum Radical Error discriminative training cri- terion is proposed, and compared with the discrimination at the character level, our new approach further reduces the character errors by 15.6% relatively (29.0% overall re- duction from the maximum likelihood baseline model) on a Chinese database.
Towards a Formal Framework for Product Line Test Development
Authors: Sungwon Kang, Jihyun Lee, Myungchul Kim, Woojin Lee
Venue: Proceedings of the 7th IEEE International Conference on Computer and Information Technology (2007)

Product line test development is more complicated than the conventional test development for a single application. There were numerous research works in the past that address various issues and aspects that arise in product line testing and test development. However, we still lack a coherent framework that can guide product line test development and link various product line development concepts to relevant product line testing concepts. In this paper we provide a basis for a formal framework for product line test development by linking product line development concepts such as feature, variability, product line architecture, component and use case scenario to product line test concepts such as test architecture, variability for test and test scenario and by providing a systematic way for deriving product line tests, adapting product line tests to a specific product and deriving product specific tests.
Combining Color, Texture and Region with Objects of User's Interest for Content-Based Image Retrieval
Authors: Muwei Jian, Junyu Dong, Ruichun Tang
Venue: Proceedings of the Eighth ACIS International Conference on Software Engineering, Artificial Intelligence, Networking, and Parallel/Distributed Computing - Volume 01 (2007)

Content-based image retrieval (CBIR) systems normally return the retrieval results according to the similarity between features extracted from the query image and candidate images. In certain circumstance, however, users concern more about objects of their interest and only wish to retrieve images containing relevant objects, while ignoring irrelevant image areas (such as the background). Previous work on retrieval of objects of user's interest (OUI) normally requires complicated segmentation of the object from the background. In this paper, we propose a method that utilize color, texture and shape features of a user specified window containing the OUI to retrieve relevant images, whereas complicated image segmentation is avoided. We use color moments and subband statistics of wavelet decomposition as color and texture features respectively. The similarity is first calculated using these features. Then shape features, generated by mathematical morphology operators, are further employed to produce the final retrieval results. We use a wide range of color images for the experiments and evaluate the performance of the proposed method in different color spaces, including RGB, HSV, YCbCr. Although simple, the method has produced promising results.
A Design-Based Structural Test Method for a Switched-Resistor DAC
Authors: Lei Ma, Geert Seuren, Robert Van Rijsinge, Corné Bastiaansen, Leon Van Dussen
Venue: Journal of Electronic Testing: Theory and Applications (2007)

In this paper, a design-based structural testing method is presented to enable a fast, low cost test for a switched-resistor digital-to-analogue converter (DAC). A 24-bit stereo DAC is used to demonstrate this. After schematic-level simulations and experimental verification, it is found that the dynamic parameter THD can be predicted by the static test. Practical production wafer test and final test results evaluate this structural test method by comparing it with the traditional THD test method. In this paper the simulation results, the relevant measurement results, and the testing results are discussed. Finally, the application recommendations are given.
A New Solution of Cooperative Games with Random Coalitional Payoffs
Authors: Fasheng Hu, Pengfei Jiang, Zhen Wang
Venue: Proceedings of the Seventh International Conference on Intelligent Systems Design and Applications (2007)

In this paper, a class of cooperative games with random payoffs is studied, a new solution which is called expected value based on players' contributions for the coalitions they belong to is introduced. Meanwhile, its uncertainty is de- fined, and their formulas are introduced. Then the prop- erties of expected value are studied, and some of them are proved in detail. In the end, an example is computed and the conclusion is made that players' expected value and its uncertainty decreases while the scale of game augments, which is similar to the Shapley value in classic cooperative game theory.
A Fast Subspace Clustering Algorithm Based on Pattern Similarity
Authors: Yanglan Gan, Jihong Guan, Hao Wang
Venue: Proceedings of the Fourth International Conference on Fuzzy Systems and Knowledge Discovery - Volume 03 (2007)

Traditional clustering models define similarity by distance over dimensions. However, distance functions are not always adequate in capturing correlations among the objects. Pattern-based clustering can discover this kind of clusters. But state-of-the-art pattern-based clustering methods are inefficient and haven't criteria to evaluate the quality of clusters. This paper presents a novel pattern similarity-based subspace clustering with the pattern tree (PPSC for short) that offers these capabilities. The method uses new evaluation criteria to discover best clusters, which enables user to find clusters according to different needs. Meanwhile, observing the analogy between mining frequent itemsets and discovering subspace clusters around random points, we apply the pattern-tree to determine subspace by scanning the database once, so it can perform efficiently in large datasets.
Evaluation of biochemistry web-based course units in medical education - a comparison
Authors: A. W. Koesling, J. Krueckeberg, G. Meyer, H. K. Matthies
Venue: Proceedings of the sixth conference on IASTED International Conference Web-Based Education - Volume 2 (2007)

Within the scope of the state-government granted project "eLearning Academic Network Lower Saxony" (ELAN), eLearning course units within different fields of expertise are developed and provided for higher education at the Hannover Medical School (MHH). The emphasis of present development work is the production and application of web-based course units for basic and advanced medical education in medicine and dentistry, where we have already gained some consolidated results. This paper compares evaluation data of students of the 3rd semester taking biochemistry courses in the Learning Management System (LMS) ILIAS from October 2004 to March 2005 with the consecutive term-time of students of the 3rd semester taking the same courses in 2005/2006.
Modelaide: a computer graphics program for the evaluation of mathematical models
Authors: Richard I. Shrager
Venue: ACM SIGGRAPH Computer Graphics (1969)

Mathematical modeling is a subtle mental exercise in which the computer, as we know it, can only serve as a mechanical aid. While the computer can improve the sum of squares given data, model, and first estimate of parameters, and while it can perform routine transformations on data, or error analyses, finally a man must judge if the fit is good, if the model makes sense, if parameters can be discarded, if an observation is faulty, and countless other judgements which are impractical to program. To quote Richard Hamming, "The purpose of computing is insight, not numbers." Our purpose is to lower the computation barrier between an investigator and a useful model.