ppxscal/embedding_network huggingface dataset:
Qos-aware channel scheduling for multi-radio/multi-channel wireless mesh networks
Authors: Marcel C. Castro, Peter Dely, Andreas J. Kassler, Nitin H. Vaidya
Venue: Proceedings of the 4th ACM international workshop on Experimental evaluation and characterization (2009)

In non-static multi-radio/multi-channel wireless mesh networks architectures such as Net-X, mesh nodes need to switch channels in order to communicate with different neighbors. Present channel schedulers do not consider the requirements of real time traffic such as voice over IP. Thus the resulting quality is low. We propose a novel channel scheduler for the Net-X platform that takes into account packet priorities. We evaluate the algorithm on the KAUMesh testbed. Our algorithm outperforms the standard round-robin scheduler both in terms of average delay and jitter.
Security and delay issues in SIP systems
Authors: Christian Callegari, Rosario G. Garroppo, Stefano Giordano, Michele Pagano
Venue: International Journal of Communication Systems (2009)

The deployment of multimedia over IP (MoIP), and in particular voice over IP services, requires to solve new security issues they introduce, before completely exploiting the great opportunities they offer to telecommunication market. Furthermore, the implementation of various security measures can cause a marked deterioration in quality of service, which is fundamental to the operation of an MoIP network that meets users' quality expectations. In particular, because of the time-critical nature of MoIP and its low tolerance for disruption and packet loss, many security measures implemented in traditional data networks are simply not applicable in their current form. This paper presents an analysis of the security options of Session Initiation Protocol- (SIP)-based MoIP architecture aimed at evaluating their impact on delay. In particular, each security option is analyzed in terms of clock cycles needed to perform the related operations. This parameter could be used to estimate the delay introduced by the security mechanisms. Moreover the paper proposes a rigorous definition of five security profiles, which provide different levels of security to a MoIP system. Copyright &copy; 2009 John Wiley & Sons, Ltd. The paper presents an analysis of the security options of SIP-based MoIP architecture aimed at evaluating their impact on QoS. In particular, each security option is analyzed in terms of clock cycles needed to perform the related operations. This parameter could be used to estimate the delay introduced by the security mechanisms. Moreover the paper proposes a rigorous definition of five security profiles, which provide different levels of security to a MoIP system. Copyright &copy; 2009 John Wiley & Sons, Ltd.
Towards symbolic mining of images with association rules: Preliminary results on textures
Authors: Matjaž Bevk, Igor Kononenko
Venue: Intelligent Data Analysis (2006)

This paper presents new textural features which are based on association rules. We give a texture representation, which is an appropriate formalism, that allows straightforward application of association rules algorithms. This representation has several good properties like invariance to global lightness and invariance to rotation. Association rules capture structural and statistical information and are very convenient to identify the structures that occur most frequently and have the most discriminative power. The results from our experiments show that this representation gives comparable results to standard texture descriptions and better results than general image descriptions.
A Cache Timing Analysis of HC-256
Authors: Erik Zenner
Venue: Selected Areas in Cryptography: 15th International Workshop, SAC 2008, Sackville, New Brunswick, Canada, August 14-15, Revised Selected Papers (2009)

In this paper, we describe a cache-timing attack against the stream cipher HC-256, which is the strong version of eStream winner HC-128. The attack is based on an abstract model of cache timing attacks that can also be used for designing stream ciphers. From the observations made in our analysis, we derive a number of design principles for hardening ciphers against cache timing attacks.
The Implementation of Fast Channel Switching in IPTV
Authors: Jinghua Lin, Weimin Lei, Song Bai, Lingnan Li
Venue: Proceedings of the 2009 Second International Conference on Intelligent Computation Technology and Automation - Volume 04 (2009)

Quality of user’s Experience (QoE) is critical to the success of an IPTV service. While there are many factors affecting IPTV service quality, a key QoE factor is the channel switching time. This paper analyzes the main reasons that cause the channel switching delay. In order to reduce the delay caused by data buffering and media Random Access Point (RAP) acquisition in UE, a method is proposed which distributes an additional media stream with the RAP beginning by unicast transport mode. For improving the unicast streaming distribution efficiency, media server caches the last RTP stream which begins with RAP for each channel and updates in real-time. In order to reduce the comparing complexity between two streams-the unicast and multicast in client-side, the RTP sequence number field has been used for identifying the play order and the RTP marker bit has been used for identifying the beginning of RAP. The method depicted in the paper has been verified in the IMS-based IPTV prototype. We use the HD samples encoded by H.264 and transported by MPEG-2 TS format as the testing media.
Predictive feedback in human simulated pendulum balancing
Authors: Peter Gawthrop, Ian Loram, Martin Lakie
Venue: Biological Cybernetics (2009)

In studies of human balance, it is common to fit stimulus-response data by tuning the time-delay and gain parameters of a simple delayed feedback model. Many interpret this fitted model, a simple delayed feedback model, as evidence that predictive processes are not required to explain existing data on standing balance. However, two questions lead us to doubt this approach. First, does fitting a delayed feedback model lead to reliable estimates of the time-delay? Second, can a non-predictive controller provide an explanation compatible with the independently estimated time delay? For methodological and experimental clarity, we study human balancing of a simulated inverted pendulum via joystick and screen. A two-step approach to data analysis is used: firstly a non-parametric model&#x2014;the closed-loop impulse response&#x2014;is estimated from the experimental data; second, a parametric model is fitted to the non-parametric impulse-response by adjusting time-delay and controller parameters. To support the second step, a new explicit formula relating controller parameters to closed-loop impulse response is derived. Two classes of controller are investigated within a common state-space context: non-predictive and predictive. It is found that the time-delay estimate arising from the second step is strongly dependent on which controller class is assumed; in particular, the non-predictive control assumption leads to time-delay estimates that are smaller than those arising from the predictive assumption. Moreover, the time-delays estimated using the non-predictive control assumption are not consistent with a lower-bound on the time-delay of the non-parametric model whereas the corresponding predictive result is consistent. Thus while the goodness of fit only marginally favoured predictive over non-predictive control, if we add the additional constraint that the model must reproduce the non-parametric time delay, then the non-predictive control model fails. We conclude (1) the time-delay should be estimated independently of fitting a low order parametric model, (2) that balance of the simulated inverted pendulum could not be explained by the non-predictive control model and (3) that predictive control provided a better explanation than non-predictive control.
The Subjective and Objective Nature of Website Aesthetic Impressions
Authors: Eleftherios Papachristos, Nikolaos Avouris
Venue: Proceedings of the 12th IFIP TC 13 International Conference on Human-Computer Interaction: Part I (2009)

This paper explores the possibility to predict positive aesthetic impression and user preference of website design through a combination of objective and subjective factors. The objective factors used are symmetry, order, balance, complexity while the subjective ones include familiarity - novelty ratings. The advantages of such an approach is the reduction of user involvement since the ratings of objective factors may be provided by a small number of design experts. We found indications that balance between certain factors maximize the possibility of users having a positive aesthetic impression.
Research on Real-Time Distinguishing Technology of Abnormal Vibration Source in High Building
Authors: Gewei Chen, Jue Dai, Handong Wang
Venue: Proceedings of the 2009 International Conference on Measuring Technology and Mechatronics Automation - Volume 01 (2009)

The safe working of high building is the important content of public safety. With time, the modern high building becomes more and more complex, and the inside electromechanical devices usually bring the abnormal vibration in building system. To ensure the safe working of building and the inside equipments, to discover and eliminate the hidden trouble in time, this paper researches on the real-time distinguishing technology of abnormal vibration source in high building based on time series analysis.
Investigating CAPTCHAs Based on Visual Phenomena
Authors: Anja B. Naumann, Thomas Franke, Christian Bauckhage
Venue: Proceedings of the 12th IFIP TC 13 International Conference on Human-Computer Interaction: Part II (2009)

We propose and evaluate several novel types of CAPTCHAs (test to tell computers and humans apart) that exploit characteristics of the human visual system. Perceptions caused by the effect of lightness constancy or grouping phenomena due to transparent motion are hard to emulate on computers and may thus provide novel authentication mechanisms.
3G and 3.5G wireless network performance measured from moving cars and high-speed trains
Authors: Keon Jang, Mongnam Han, Soohyun Cho, Hyung-Keun Ryu, Jaehwa Lee, Yeongseok Lee, Sue B. Moon
Venue: Proceedings of the 1st ACM workshop on Mobile internet through cellular networks (2009)

In recent years, the world has witnessed the deployment of several 3G and 3.5G wireless networks based on technologies such as CDMA 1x EVolution Data-Only (EVDO), High-Speed Downlink Packet Access (HSDPA), and mobile WiMax (e.g., WiBro). Although 3G and 3.5G wireless networks support enough bandwidth for typical Internet applications, their performance varies greatly due to the wireless link characteristics. We present a measurement analysis of the performance of UDP and TCP over 3G and 3.5G wireless networks. The novelty of our measurement experiments lies in the fact that we took our measurements in a fast moving car on a highway and in a high-speed train running at 300 km/h. Predictably, our results show that mobile nodes experience far worse performance than stationary nodes over the same network.
Embedded Bernoulli Mixture HMMs for Continuous Handwritten Text Recognition
Authors: Adrià Giménez, Alfons Juan
Venue: Proceedings of the 13th International Conference on Computer Analysis of Images and Patterns (2009)

Hidden Markov Models (HMMs) are now widely used in off-line handwritten text recognition. As in speech recognition, they are usually built from shared, embedded HMMs at symbol level, in which state-conditional probability density functions are modelled with Gaussian mixtures. In contrast to speech recognition, however, it is unclear which kind of real-valued features should be used and, indeed, very different features sets are in use today. In this paper, we propose to by-pass feature extraction and directly fed columns of raw, binary image pixels into embedded Bernoulli mixture HMMs, that is, embedded HMMs in which the emission probabilities are modelled with Bernoulli mixtures. The idea is to ensure that no discriminative information is filtered out during feature extraction, which in some sense is integrated into the recognition model. Good empirical results are reported on the well-known IAM database.
Colour Gamut Mapping as a Constrained Variational Problem
Authors: Ali Alsam, Ivar Farup
Venue: Proceedings of the 16th Scandinavian Conference on Image Analysis (2009)

We present a novel, computationally efficient, iterative, spatial gamut mapping algorithm. The proposed algorithm offers a compromise between the colorimetrically optimal gamut clipping and the most successful spatial methods. This is achieved by the iterative nature of the method. At iteration level zero, the result is identical to gamut clipping. The more we iterate the more we approach an optimal, spatial, gamut mapping result. Optimal is defined as a gamut mapping algorithm that preserves the hue of the image colours as well as the spatial ratios at all scales. Our results show that as few as five iterations are sufficient to produce an output that is as good or better than that achieved in previous, computationally more expensive, methods. Being able to improve upon previous results using such low number of iterations allows us to state that the proposed algorithm is O(N), N being the number of pixels. Results based on a challenging small destination gamut supports our claims that it is indeed efficient.
Perceptually-Informed Virtual Environment (PerceiVE) Design Tool
Authors: Anna Skinner, Jack Vice, Corinna Lathan, Cali Fidopiastis, Chris Berka, Marc Sebrechts
Venue: Proceedings of the 5th International Conference on Foundations of Augmented Cognition. Neuroergonomics and Operational Neuroscience: Held as Part of HCI International 2009 (2009)

Virtual environments (VE's) are becoming more and more prevalent as training tools for both military and civilian applications. The common assumption is that the more realistic the VE, the better the transfer of training to real world tasks. However, some aspects of task content and fidelity may result in stronger transfer of training than even the most high fidelity simulations. This research effort seeks to demonstrate the technical feasibility of a Perceptually-informed Virtual Environment (PerceiVE) Design Tool, capable of dynamically detecting changes in operator behavior and physiology throughout a VE experience and comparing those changes to operator behavior and physiology in real-world tasks. This approach could potentially determine which aspects of VE fidelity will have the highest impact on transfer of training. A preliminary study was conducted in which psychophysiological and performance data were compared for a visual search tasks with low and high fidelity conditions. While no significant performance effects were found across conditions, event-related potential (ERP) data revealed significant differences between the low and high fidelity stimulus conditions. These results suggest that psychophysiological measures may provide a more sensitive and objective measure for determining VE fidelity requirements.
Speech-Based Navigation: Improving Grid-Based Solutions
Authors: Shaojian Zhu, Yao Ma, Jinjuan Feng, Andrew Sears
Venue: Proceedings of the 12th IFIP TC 13 International Conference on Human-Computer Interaction: Part I (2009)

Speech-based technology is a useful alternative to traditional input techniques such as the keyboard and mouse. For people with disabilities that hinder use of traditional input devices, a hands-free speechbased interaction solution is highly desirable. Various speech-based navigation techniques have been discussed in the literature and employed in commercial software applications. Among them, grid-based navigation has shown both potential and limitations. Grid-based solutions allow users to position the cursor using recursive grids to `drill down' until the cursor is in the desired location. We report the results of an empirical study that assessed the efficacy of two enhancements to the grid-based navigation technique: magnification and fine-tuning. Both mechanisms were designed to facilitate the process of selecting small targets. The results suggest that both the magnification and the fine-tuning capabilities significantly improved the participants' performance when selecting small targets and that fine-tuning also has benefits when selecting larger targets. Participants preferred the solution that provided both enhancements.
Generating and solving logic puzzles through constraint satisfaction
Authors: Barry O'Sullivan, John Horan
Venue: Proceedings of the 22nd national conference on Artificial intelligence - Volume 2 (2007)

Solving logic puzzles has become a very popular past-time, particularly since the Sudoku puzzle started appearing in newspapers all over the world. We have developed a puzzle generator for a modification of Sudoku, called Jidoku, in which clues are binary disequalities between cells on a 9 × 9 grid. Our generator guarantees that puzzles have unique solutions, have graded difficulty, and can be solved using inference alone. This demonstration provides a fun application of many standard constraint satisfaction techniques, such as problem formulation, global constraints, search and inference. It is ideal as both an education and outreach tool. Our demonstration will allow people to generate and interactively solve puzzles of user-selected difficulty, with the aid of hints if required, through a specifically built Java applet.
Modeling Web Applications and Generating Tests: A Combination and Interactions-guided Approach
Authors: Bo Song, Huaikou Miao
Venue: Proceedings of the 2009 Third IEEE International Symposium on Theoretical Aspects of Software Engineering (2009)

As more and more services and information are made available over the Internet and intranets, Web sites have become extraordinarily complex, while their correctness and reliability are often crucial to the success of businesses and organizations. Additionally, the behavior of the Web browsers may have impact on the correctness of the web applications: a web application providing all correct functionality by itself may however malfunction when it is put into its supporting environment. Consequently, the Web browser’s interactions should be taken into account at the stage of modeling Web applications. Software testing is a primary way of improving software reliability and assuring software quality. This paper proposed an approach to modeling Web applications by the means of combination of Web functional modules and the browser’s interactions. A Web application is referred to as a system which consisted of many different functional modules. At last, test generation is given out which satisfies the corresponding coverage criteria.
Reconstructing 3D Facial Shape Using Spherical Harmonics
Authors: Chengming Zou, Guanghui Zhao, Edwin R. Hancock
Venue: Proceedings of the 15th International Conference on Image Analysis and Processing (2009)

It is now well established that 3D facial shape can be effectively and conveniently reconstructed using spherical harmonics. This paper extends the state-of-the-art by showing how to recover a 3D facial shape reconstruction using a spherical parameterization and minimizing a Harmonic Energy based on spherical medians. The solution is formulated as a linear system and we propose an iterative residual fitting algorithm (LSQR-IRF) to solve it. We demonstrate the effectivenss of the method on range-data.
Efficient querying relaxed dominant relationship between product items based on rank aggregation
Authors: Zhenglu Yang, Lin Li, Masaru Kitsuregawa
Venue: Proceedings of the 23rd national conference on Artificial intelligence - Volume 2 (2008)

Current search engines cannot effectively rank those relational data, which exists on dynamic websites supported by online databases. In this study, to rank such structured data, we propose a new model, Relaxed Dominant Relationship (RDR), which extends the state-of-the-art work by incorporating rank aggregation methods. We propose efficient strategies on building compressed data structure to encode the core part of RDR between items. Efficient querying approaches are devised to facilitate the ranking process and to answer the RDR query. Extensive experiments are conducted and the results illustrate the effectiveness and efficiency of our methods.
Human Being and Mathematics Logical and Mathematical Thinking
Authors: Rudolf Wille
Venue: Proceedings of the 17th International Conference on Conceptual Structures: Conceptual Structures: Leveraging Semantic Technologies (2009)

Logical thinking as an expression of human reason grasps the actual reality by the basic forms of thinking: concept, judgment, and conclusion. Mathematical thinking abstracts from logical thinking to disclose a cosmos of forms of potential realities hypothetically. Mathematics as a form of mathematical thinking can therefore support humans within their logical thinking about realities which, in particular, promotes sensible actions. This train of thought has been convincingly differentiated by Peirce's philosophical pragmatism and concretized by a "contextual logic" invented by members of the mathematics department at the TU Darmstadt.
On the relative value of cross-company and within-company data for defect prediction
Authors: Burak Turhan, Tim Menzies, Ayşe B. Bener, Justin Di Stefano
Venue: Empirical Software Engineering (2009)

We propose a practical defect prediction approach for companies that do not track defect related data. Specifically, we investigate the applicability of cross-company (CC) data for building localized defect predictors using static code features. Firstly, we analyze the conditions, where CC data can be used as is. These conditions turn out to be quite few. Then we apply principles of analogy-based learning (i.e. nearest neighbor (NN) filtering) to CC data, in order to fine tune these models for localization. We compare the performance of these models with that of defect predictors learned from within-company (WC) data. As expected, we observe that defect predictors learned from WC data outperform the ones learned from CC data. However, our analyses also yield defect predictors learned from NN-filtered CC data, with performance close to, but still not better than, WC data. Therefore, we perform a final analysis for determining the minimum number of local defect reports in order to learn WC defect predictors. We demonstrate in this paper that the minimum number of data samples required to build effective defect predictors can be quite small and can be collected quickly within a few months. Hence, for companies with no local defect data, we recommend a two-phase approach that allows them to employ the defect prediction process instantaneously. In phase one, companies should use NN-filtered CC data to initiate the defect prediction process and simultaneously start collecting WC (local) data. Once enough WC data is collected (i.e. after a few months), organizations should switch to phase two and use predictors learned from WC data.
Interaction Comparison among Media Internet Genre
Authors: Sang Hee Kweon, Eun Joung Cho, Ae Jin Cho
Venue: Proceedings of the 13th International Conference on Human-Computer Interaction. Part I: New Trends (2009)

This research explores interactivity dimension in the portal media (such as Yahoo, Naver, Daum, Paran, and Nate). The research is designed to measure user's perception of interactivity in the portal site at the three levels including 1) media 2) contents, 3) perception of HCI and CMC. This research also seeks the associated variables relationship among those variables through SEM (structural equation model). The 587 data was collected and was analyzed to test the hypotheses. The results shows that the dimension of the media side's interactivity affected to the content's side's interactivity. The content side's interactivity affected the user's perception of portal media level either HCI and CMC media.