ppxscal/embedding_network huggingface dataset:
A Comment on Ryser&#x2019;s Conjecture for Intersecting Hypergraphs
Authors: Toufik Mansour, Chunwei Song, Raphael Yuster
Venue: Graphs and Combinatorics (2009)

Let $$\tau({\mathcal{H}})$$be the cover number and $$\nu({\mathcal{H}})$$be the matching number of a hypergraph $${\mathcal{H}}$$. Ryser conjectured that every r-partite hypergraph $${\mathcal{H}}$$satisfies the inequality $$\tau({\mathcal{H}}) \leq (r-1) \nu ({\mathcal{H}})$$. This conjecture is open for all r &#x2265; 4. For intersecting hypergraphs, namely those with $$\nu({\mathcal{H}}) = 1$$, Ryser&#x2019;s conjecture reduces to $$\tau({\mathcal{H}}) \leq r-1$$. Even this conjecture is extremely difficult and is open for all r &#x2265; 6. For infinitely many r there are examples of intersecting r-partite hypergraphs with $$\tau({\mathcal{H}}) = r-1$$, demonstrating the tightness of the conjecture for such r. However, all previously known constructions are not optimal as they use far too many edges. How sparse can an intersecting r-partite hypergraph be, given that its cover number is as large as possible, namely $$\tau({\mathcal{H}}) \ge r-1$$? In this paper we solve this question for r &#x2264; 5, give an almost optimal construction for r =&#x00a0;6, prove that any r-partite intersecting hypergraph with &#x03c4;(H) &#x2265; r&#x00a0;&#x2212;&#x00a0;1 must have at least $$(3-\frac{1}{\sqrt{18}})r(1-o(1)) \approx 2.764r(1-o(1))$$edges, and conjecture that there exist constructions with &#x0398;(r) edges.
Supporting community in third places with situated social software
Authors: Joseph F. McCarthy, Shelly D. Farnham, Yogi Patel, Sameer Ahuja, Daniel Norman, William R. Hazlewood, Josh Lind
Venue: Proceedings of the fourth international conference on Communities and technologies (2009)

The Community Collage (CoCollage) is designed to cultivate community in a café, a quintessential "third place", by bringing the richness of online social software into a physical community space. The system shows photos and quotes uploaded to a web site by café patrons and staff on a large computer display in the café, providing a new channel for awareness, interactions and relationships among people there. We describe the CoCollage system and report on insights and experiences resulting from a 2-month deployment of the system, focusing on the impact the system has had on the sense of community within the café.
Comparison of Rule-Based and DTMRI-Derived Fibre Architecture in a Whole Rat Ventricular Computational Model
Authors: Martin J. Bishop, Patrick Hales, Gernot Plank, David J. Gavaghan, Jürgen Scheider, Vicente Grau
Venue: Proceedings of the 5th International Conference on Functional Imaging and Modeling of the Heart (2009)

The anisotropic electrical conduction within myocardial tissue due to preferential cardiac myocyte orientation (`fibre orientation) is known to impact strongly in electrical wavefront dynamics, particularly during arrhythmogenesis. Faithful representation of cardiac fibre architecture within computational cardiac models which seek to investigate such phenomena is thus imperative. Drawbacks in derivation of fibre structure from imaging modalities often render rule-based representations based on a priori knowledge preferential. However, the validity of using such rule-based approaches within whole ventricular models remains unclear. Here, we present the development of a generic computational framework to directly compare the fibre architecture predicted by rule-based methods used within whole ventricular models against fibre structure derived from DTMRI data, and assess how relative differences influence propagation dynamics throughout the ventricles. Results demonstrate the close overall match between the methods within the rat ventricles, and highlight regions for potential rule-adaption.
Alternative marginal-cost pricing for road networks
Authors: Yafeng Yin, Siriphong Lawphongpanich
Venue: Netnomics (2009)

In the literature, several studies have algebraically characterized the set of toll vectors or patterns that, when added to a user equilibrium problem, its solution would be system optimal. Toll vectors in this set are termed "valid." While the toll vector commonly advocated in the literature, i.e., one that equates the toll on each link to its marginal external cost, is always valid, other valid toll vectors generally exist and many leave some utilized links in the network untolled. On the surface, this may appear unreasonable and seems to violate the principle of marginal-cost pricing. This note shows that, when travel demands are elastic, all valid toll vectors satisfy this principle, in that the total tolls for each path equals the congestion externality an additional traveler on the path imposes on others.
Analyses of task based learning in developing "M-Learn" mobile learning software solution: case study
Authors: Majlinda Fetaji, Bekim Fetaji
Venue: Proceedings of the 8th WSEAS International Conference on Software engineering, parallel and distributed systems (2009)

Developing mobile software solutions in order to enhance learning in University environments by using the new mobile communication technology is becoming a very popular research focus. However there is a lack of research on the instruction method that should be used in the development of mobile learning software as a very important factor in the learning process and in the software engineering process. In this paper we investigate, develop and analyses a mobile software solution in using the Task Based Learning model. The research focuses on the developed software solution and reviews learning modeling approach focusing on task based learning that from the findings is concluded as the best approach for mobile learning. For testing purposes developed is a software prototype called M-Learn and its analyses has been investigated and recommendations for developing similar software solutions have been defined.
Electromagnetic processes at laser beam processing assisted by an active gas jet
Authors: Marian Pearsica, Ioan-Gheorghe Ratiu, Claudia-Georgeta Carstea, Cristian Constantinescu, Constantin Strimbu
Venue: Proceedings of the 10th WSEAS international conference on Mathematical methods, computational techniques and intelligent systems (2008)

The first part of this paper deals with the differential equations system, which governs the laser processing of materials in the presence of the O2 jet, occurring on the mobile irradiation. It deals also with the hypotheses basing the equations system obtained. Spatial and temporally distribution of temperature inside the material is governed by the full source of temperature, which has been modelled by taking into consideration the fact that the irradiation is made with a CO2 laser with a "Gaussian distribution" of photons beam's intensity and oxidizing energy. The second part of paper deals with the determination of separation frontiers equations and graphical representations of radial distribution of the temperature of the three phases: solid, liquid and vapours. The results thus obtained allow the determining of the technological parameters of processing and the material constants.
Synthesizing Frontal Faces on Calibrated Stereo Cameras for Face Recognition
Authors: Kin-Wang Cheung, Jiansheng Chen, Yiu-Sang Moon
Venue: Proceedings of the Third International Conference on Advances in Biometrics (2009)

Current automatic face recognition systems often require users to face towards the capturing camera. To extent these systems for user non-intrusive application scenarios such as video surveillance, we propose a stereo camera configuration to synthesize a frontal face image from two non-frontal face images. After the head pose has been estimated, a frontal face image is synthesized using face warping and view morphing techniques. Face identification experiments reveal that using the synthetic frontal images can achieve comparable performance with real frontal face images.
Do Various Self-Regulatory Processes Predict Different Hypermedia Learning Outcomes?
Authors: Roger Azevedo, Amy Witherspoon, Shanna Baker, Jeffrey Greene, Daniel Moos, Jeremiah Sullins, Andrew Trousdale, Jennifer Scott
Venue: Proceeding of the 2007 conference on Artificial Intelligence in Education: Building Technology Rich Learning Contexts That Work (2007)

Eighty-two (N = 82) college students with little knowledge of the circulatory system were randomly assigned either to the control condition (SRL; self-regulated learning) or human tutoring (ERL; externally-regulated learning) condition. Learners in the SRL condition regulated their own learning, while learners in the ERL condition had access to a human tutor who facilitated their self-regulated learning. All learners were given 40 minutes to learn about the circulatory system. We collected several pretest and posttest learning measures and collected think-aloud protocols during learning. Generally, the learners in the ERL condition significantly outperformed the learners in SRL condition. In comparison to the SRL condition, results indicate that learners in the ERL condition deployed significantly more SRL processes related to planning, monitoring, and handling task difficulties. Each of the classes of SRL processes was predictive of learners' performance on different posttest measures.
Supporting the creative drive: investigating paralinguistic voice as a mode of interaction for artists with upper limb disabilities
Authors: Dharani Perera, R. T. Jim Eales, Kathy Blashki
Venue: Universal Access in the Information Society (2009)

For people with upper limb disabilities visual art is an important activity that allows for expression of individuality and independence. They show remarkable endurance, patience and determination to adapt their remaining capabilities to create visual art. There are significant advantages of digital technologies in assisting artists with upper limb disabilities. Paralinguistic voice recognition technologies have proven to be a particularly promising mode of interaction. Despite these benefits, technological support for people with upper limb disabilities to create visual art is scarce. This paper reports on a number of case studies of several artists with upper limb disabilities. These case studies illustrate the struggles they face to be creative and also show the significant advantages of digital technologies in assisting such artists. An investigation into people&#x2019;s ability to use the volume of their voice to control cursor movement to create drawings on the screen is also reported. With motivation, training and practise, use of volume to control drawing tasks shows great promise. It is believed that paralinguistic voice has wider implications beyond assisting artists with upper limb disabilities, such as: an alternative mode of interaction for disabled people to perform tasks other than creating visual art, alternative mode of interaction for hands busy environments and as a voice training system for people with speech impairments.
Guest Editors' Introduction: Embedded Software Technologies and Trends
Authors: Christof Ebert, Jürgen Salecker
Venue: IEEE Software (2009)

Our world and society are shaped and governed by embedded systems. Examples of embedded systems include pacemakers, implanted biosensors, RFID tags, cell phones, home appliances, satellites, train control systems, and automotive components. In this special-issue introduction, we provide a snapshot of the topic of embedded software. We show its similarities to general-purpose IT and highlight embedded systems' peculiarities. In addition to highlighting trends and topics worth thinking about, we relate hands-on experiences from industry projects from which all of us can learn, independent of which type of software and domain we deal with in our day-to-day engineering work.
Video synchronization from human motion using rank constraints
Authors: Philip A. Tresadern, Ian D. Reid
Venue: Computer Vision and Image Understanding (2009)

This paper presents a method of synchronizing video sequences that exploits the non-rigidity of sets of 3D point features (e.g., anatomical joint locations) within the scene. The theory is developed for homography, perspective and affine projection models within a unified rank constraint framework that is computationally cheap. An efficient method is then presented that recovers potential frame correspondences, estimates possible synchronization parameters via the Hough transform and refines these parameters using non-linear optimization methods in order to recover synchronization to sub-frame accuracy, even for sequences of unknown and different frame rates. The method is evaluated quantitatively using synthetic data and demonstrated qualitatively on several real sequences.
Ad-hoc composition of pervasive services in the PalCom architecture
Authors: David Svensson Fors, Boris Magnusson, Sven Gestegård Robertz, Görel Hedin, Emma Nilsson-Nyman
Venue: Proceedings of the 2009 international conference on Pervasive services (2009)

We present an architecture supporting ad-hoc composition of pervasive services, an open-source framework that implements it, and the key design principles behind it. The architecture focuses on direct human interaction, supporting combination of devices and services that are not explicitly designed to work together. The focus is on local networks, but extension is possible to wide area networks, interconnecting several local networks. The information about how services are connected and coordinated is collected in a new construct called assemblies. Separating this information from the services themselves allows combination of existing services in new creative ways without changing them. Assemblies can provide new services and in this way be organized hierarchically. The assembly makes the architecture of a pervasive system explicit, providing an overview understandable to users. Discovery and connections across different network technologies is supported. The architecture has been used for applications in large scale networks, and offers mechanisms useful for system integration in general.
A New Collaborative Working Environment for Concurrent Engineering in Manufacturing Industry
Authors: Dragan Stokic
Venue: Proceeding of the 2006 conference on Leading the Web in Concurrent Engineering: Next Generation Concurrent Engineering (2006)

The paper addresses the problems of collaboration of teams in manufacturing industry in the scope of concurrent engineering (CE) processes. The problem of involving shop-floor teams in product/process improvements is specifically addressed. The objective is to develop a new information technology platform based on software collaborative services supporting different CE processes where different teams --product design, maintenance, shop-floor teams etc. --around the complex assembly and manufacturing lines have to be involved. The platform is one of the first attempts to apply Collaborative Reference Architecture to support CE in manufacturing industry. The work presented addresses a development of new tools and the core collaborative services for design of such a platform. Several current applications of such platform are indicated.
Determining the benefits of direct-touch, bimanual, and multifinger input on a multitouch workstation
Authors: Kenrick Kin, Maneesh Agrawala, Tony DeRose
Venue: Proceedings of Graphics Interface 2009 (2009)

Multitouch workstations support direct-touch, bimanual, and multifinger interaction. Previous studies have separately examined the benefits of these three interaction attributes over mouse-based interactions. In contrast, we present an empirical user study that considers these three interaction attributes together for a single task, such that we can quantify and compare the performances of each attribute. In our experiment users select multiple targets using either a mouse-based workstation equipped with one mouse, or a multitouch workstation using either one finger, two fingers (one from each hand), or multiple fingers. We find that the fastest multitouch condition is about twice as fast as the mouse-based workstation, independent of the number of targets. Direct-touch with one finger accounts for an average of 83% of the reduction in selection time. Bimanual interaction, using at least two fingers, one on each hand, accounts for the remaining reduction in selection time. Further, we find that for novice multitouch users there is no significant difference in selection time between using one finger on each hand and using any number of fingers for this task. Based on these observations we conclude with several design guidelines for developing multitouch user interfaces.
Code and Data Propagation on a PC's Multi-Agent System
Authors: Dariusz Król, Aleksander Lupa
Venue: Proceeding of the 2008 conference on New Trends in Multimedia and Network Information Systems (2008)

We present the concept of code and data propagation on a PC's multi-agent system. First, the idea of the prime numbers problem in distributed environment is defined and explained. Afterwards, the code and data propagation in a multi-agent system is described, which is in many cases based on the object migration. In addition, the experiments are conducted in a heterogeneous environment. The main aim is to find optimal configuration after minimal number of migrations for that platform.
Impact and consequences of evapotranspiration changes on water resources availability in the arid Zhangye Basin, China
Authors: Xiaomei Jin, M. E. Schaepman, J. G. P. W. Clevers, Z. Bob Su
Venue: International Journal of Remote Sensing (2009)

Evapotranspiration (ET) plays an important role in the hydrological cycle and it is essential to estimate ET accurately for the evaluation of available water resources. This is most important in arid and semi-arid regions. In this paper, the long-term changes in daily ET in the semi-arid Zhangye Basin in northwest China and its impact factors were studied. The spatial distribution of ET was assessed by using the Surface Energy Balance System (SEBS). Cloud-free National Oceanic and Atmospheric Administration Advanced (NOAA) Very High Resolution Radiometer (AVHRR) September images over the Zhangye Basin from 1990 to 2004 were used in combination with SEBS to estimate ET at a spatial resolution of 1.1 km. This daily ET was converted to a monthly ET (for September) using daily pan evaporation values from a meteorological station in the study area. Spatial aggregation of all pixels yielded the total monthly ET for the whole study area. Subsequently, the monthly ET was extrapolated to annual ET values using the pan evaporation data. The results were validated with ground-based measurements on the water balance for the whole Zhangye Basin. The annual ET increased gradually from 23.7×108 m3 in 1990 to 26.9×108 m3 in 2004 for the Zhangye Basin. The main cause appeared to be change in vegetation.
Scaffolding inquiry learning: How much intelligence is needed and by whom?
Authors: Ton de Jong
Venue: Proceeding of the 2005 conference on Artificial Intelligence in Education: Supporting Learning through Intelligent and Socially Informed Technology (2005)

Inquiry learning is way of learning in which learners act like scientists and discover a domain by employing processes such as hypothesis generation, experiment design, and data interpretation. The sequence of these learning processes and the choice for specific actions (e.g., what experiment to perform) are determined by the learners themselves. This student centeredness makes that inquiry learning heavily calls upon metacognitive processes such as planning and monitoring. These inquiry and metacognitive processes make inquiry learning a demanding task. When inquiry is combined with modelling and collaboration facilities the complexity of the learning process even increases. To make inquiry learning successful, the inquiry (and modelling and collaborative) activities need to scaffolded. Scaffolding can mean that the learning environment is structured or that learners are provided with cognitive tools for specific activities. AI techniques can be used to make scaffolds more adaptive to the learner or to developments in the learning process. In this presentation an overview of (adaptive and non-adaptive) scaffolds for inquiry learning in simulation based learning environments will be discussed.details will follow.
Design and architecture of a new crisis situation room (CSR)
Authors: Ramezanali Azadehdel, Kourosh Dadashtabar, Ehsan Enami
Venue: Proceedings of the 10th Annual International Conference on Digital Government Research: Social Networks: Making Connections between Citizens, Data and Government (2009)

Crisis is an abnormal and emergency situation which would occur as a result of natural or unnatural disasters. Considering geographical situation of Iran, constant readiness of responsible crisis managers and organizations is essential. They should be prepared for taking correct and real-time decisions and finally conducting necessary actions to respond to the crisis. With respect to knowledge and experiences gained from incidents occurred in Iran and other countries, crisis experts believe that the most important issues in crisis management realm are: (1) Effective coordination and cooperation among organizations which are responsible for crisis management, and (2) Effective utilization of available assets for responding to the crisis. Thus utilizing an architectural mechanism that has anticipated necessary solutions for crisis situation is a major concern of top national managers. This article proposes a crisis management system which is based on enterprise architecture. By integrating and facilitating interactions between different parts of an organization, such as: information, communication, and operation, this system provides crisis commander and other key players with a basis on which decision could be made more effectively and situation could be handled more efficiently. Early outcome of such a system is determination of the followings: (1) operation scope, (2) acting units' mission and tasks, (3) organizational processes, (4) counter crisis scenarios, (5) mission assignment and execution procedures and categories, (6) communications among operational members and nodes, (7) mission priorities (8) information content transferred among members, (9) necessary features of hardware and software systems, and (10) illustration of communication among subsystems. Improving the accuracy and speed of commander's decision making process by means of creating a common picture of the situation and facilitating information, service and capability sharing during crisis period is another result of this system. At the end of this article, a simple application of this system would be presented based on C4ISR architecture framework and software development methodology.
Using Ontologies for an Effective Design of Collaborative Learning Activities
Authors: Seiji Isotani, Riichiro Mizoguchi
Venue: Proceeding of the 2007 conference on Artificial Intelligence in Education: Building Technology Rich Learning Contexts That Work (2007)

Although artificial intelligence has been successfully introduced to enhance Education through technologies in the past few years, major challenges still remain. One of them is how to represent the knowledge of intelligent systems. To represent the knowledge of systems to support collaborative learning is particularly challenging because it is based on various learning theories and given the complexity of group learning. The main objective of this work is to introduce an ontological infrastructure on which we can build well-grounded theoretical knowledge based on learning theories and to show how we can use it to develop programs to support intelligent guidance for an effective design of group activities.