ppxscal/embedding_network huggingface dataset:
Toward Quality-Centered Design of Groupware Architectures
Authors: James Wu, T. C. Graham
Venue: Engineering Interactive Systems: EIS 2007 Joint Working Conferences, EHCI 2007, DSV-IS 2007, HCSE 2007, Salamanca, Spain, March 22-24, 2007. Selected Papers (2008)

Challenges in designing effective groupware include technical issues associated with concurrent and distributed work and social issues associated with supporting group activities. To address some of these problems, we have developed a quality-centered architectural design framework that links requirements analysis to architectural design decisions for groupware systems. The framework supports reasoned architectural design choices that are used to tailor software architecture to the unique quality and functional requirements of the software being developed. The framework has been applied to the development of the Software Design Board, a tool for collaborative software engineering.
Strategies for Solving Constraints in Type and Effect Systems
Authors: Jurriaan Hage, Bastiaan Heeren
Venue: Electronic Notes in Theoretical Computer Science (ENTCS) (2009)

Turning type and effect deduction systems into an algorithm is a tedious and error-prone job, and usually results in an implementation that leaves no room to modify the solving strategy, without actually changing it. We employ constraints to declaratively specify the rules of a type system. Starting from a constraint based formulation of a type system, we introduce special combinators in the type rules to specify in which order constraints may be solved. A solving strategy can then be chosen by giving a particular interpretation to these combinators, and the resulting list of constraints can be fed into a constraint solver; thus the gap between the declarative specification and the deterministic implementation is bridged. This design makes the solver simpler and easier to reuse. Our combinators have been used in the development of a real-life compiler.
Image Denoising for Adaptive Threshold Function Based on the Dyadic Wavelet Transform
Authors: Zhenghong Huang, Li Xia
Venue: Proceedings of the 2009 International Conference on Electronic Computer Technology (2009)

Based on the characteristic of dyadic wavelet transform to image denoising, this paper presents that denoising precision can be improved by the way that adopting different thresholds according to the different scales of the wavelet coefficients of image and noise to establish adaptive layered threshold function which adapts to it and reconstruct the wavelet. The experiment shows that by the method above the effect of image denoising is obviously superior to that of fixed threshold function.
Modeling and simulation of e-mail social networks: a new stochastic agent-based approach
Authors: Fabian Menges, Bud Mishra, Giuseppe Narzisi
Venue: Proceedings of the 40th Conference on Winter Simulation (2008)

Understanding how the structure of a network evolves over time is one of the most interesting and complex topics in the field of social networks. In our attempt to model the dynamics of such systems, we explore an agent-based approach to model growth of email-based social networks, in which individuals establish, maintain and allow atrophy of links through contact-lists and emails. The model is based on the idea of common neighbors, but also on a detailed specialization of the classical preferential attachment theory, thus capturing a deeper understanding of the topology of inter-node connections. In our event-based simulation that schedules the agents' actions over time, the proposed model is amenable to significant efficiency improvements through an application of the Gillespie stochastic simulation schemes. Computer simulation results are used to validate the model by showing that its unique features endow it with ability to simulate real-world email networks with convincing realism.
Clustering Routing Based Maximizing Lifetime for Wireless Sensor Networks
Authors: Yanjing Sun, Xiangping Gu
Venue: International Journal of Distributed Sensor Networks (2009)

Distinguished from traditional wireless networks, sensor networks are characterized with severe power, computation, and memory constraints. Due to strict energy constraint, innovative techniques that improve energy efficiency to prolong the network lifetime are highly required. Many solutions and algorithms for overcoming the problem depend on decomposing the network into a number of administrative entities called clusters. The structure imposed by clustering makes it somewhat easier to manage the problem introduced by the complexity of large-scale WSNs. Hierarchical (clustering) mechanisms are especially effective in increasing network scalability and reducing energy depletion, which have been extensively exploited. We propose and evaluate an energy efficient clustering scheme based on LEACH (low energy adoptive clustering hierarchy), that is, LEACH-Energy Distance (LEACH-ED). In LEACH-ED, cluster heads are elected by a probability based on the ratio between residual energy of node and the total current energy of all of the sensor nodes in the network. In addition, it also considers the distance of any two cluster heads to uniform the clustering, namely, if the distance between some node and an existing cluster head in the round less than the distance threshold, the node cannot be elected as a cluster head. The method uses two different sorts of nodes which are called special node and normal node. Assume that special nodes are uniformly distributed in the interested area. In the algorithm, it sets a distance threshold  [image omitted], where S is the acreage of interested filed, N is the number of sensor nodes in the entire network, and p is the desired percentage of cluster heads in each round. Each node generates a random probability p at the beginning of a new round and computes the threshold value (T(n)). In case of p
PhotoBuilder -- 3D Models of Architectural Scenes from Uncalibrated Images
Authors: Roberto Cipolla, Duncan Robertson, Edmond Boyer
Venue: Proceedings of the IEEE International Conference on Multimedia Computing and Systems - Volume 2 (1999)

We address the problem of recovering 3D models from uncalibrated images of architectural scenes. We propose a simple, geometrically intuitive method which exploits the strong rigidity constraints of parallelism and orthogonality present in indoor and outdoor architectural scenes. We show how these simple constraints can be used to calibrate the cameras and to recover the projection matrices for each viewpoint.The projection matrices are used to recover partial 3D models of the scene and these can be used to visualise new viewpoints. Our approach does not need any {\it a priori} information about the cameras being used.A working system called {\em PhotoBuilder} had been designed and implemented to allow a user to interactively build a VRML model of a building from uncalibrated images from arbitrary viewpoints.
SMO (smart multimedia object) for distance education: learning via interactive digital TV - requirement and specification
Authors: Momouh Khadraoui, Beat Hirsbrunner
Venue: Proceedings of the 2008 International Conference on Advances in Computer Entertainment Technology (2008)

This paper reports the implementation of the concepts of the Smart Multimedia Object model (SMO) as a simple IDTV application for distance education.
Engineering computer network (ECN): a hardwired network of UNIX computer systems
Authors: Kai Hwang, Benjamin W. Wah, Fayé A. Briggs
Venue: Proceedings of the May 4-7, 1981, national computer conference (1981)

This paper reports the design and operational experiences of a packet-switched local computer network developed at Purdue University. Hardwired communication links (1 mega-baud) are used to interconnect seven UNIX computer systems (two PD11/70, one VAX 11/780, and 4 PDP11/45). Over 20 microprocessors and 210 timesharing CRT terminals are connected to the seven hosts. Instead of using the UUCP protocols for dial-up UNIX networks, several protocol programs are locally developed to make possible the hardwired UNIX networking. The network provides the capabilities of virtual terminal access, remote process execution, file transfer, load balancing, and user programmed network I/O. Only at the lowest protocol level is the DDCMP of DECNET used. The network is expandable and provides appreciable bandwidth with moderate cost and low system overhead. Described in this paper are the network architecture, system components, protocol hierarchy, local UNIX extension, load balancing methods, and performance evaluation of the Purdue ECN network.
Intervalley scattering in GaAs/AlGaAs quantum wells and quantum cascade lasers
Authors: James Mc Tavish, Zoran Ikonić, Dragan Indjin, Paul Harrison
Venue: Microelectronics Journal (2009)

The results of simulations of Γ-X scattering in GaAs/AlGaAs quantum wells are presented, discussing the importance of the mole fraction, doping density, and lattice and electron temperatures in determining the scattering rates. A systematic study of Γ-X scattering in GaAs/AlxGa1-xAs heterostructures, using a single quantum well to determine the importance of well width, molar concentration x, lattice temperature, and doping density, has been performed. After this we consider a double quantum well to determine the role of intervalley scattering in the transport through single-layer heterostructures, i.e. Γ-X-Γ scattering compared with Γ-Γ scattering. Finally, we estimate the relative importance of intervalley scattering in a GaAs-based quantum-cascade laser device and compare it with other relevant scattering mechanisms important to describe carrier dynamics in the structure. Our simulations suggest that Γ-X scattering can be significant at room temperature but falls off rapidly at lower temperatures.
A nanoanalytical investigation of high-k dielectric gate stacks for GaAs based MOSFET devices
Authors: P. Longo, A. J. Craven, M. C. Holland, D. A. J. Moran, I. G. Thayne
Venue: Microelectronic Engineering (2009)

In this paper a quantitative determination of the elemental distributions across a ~10nm Ga"2O"3/GdGaO layer with a Pt metal gate cap on top of an InGaAs/AlGaAs/GaAs substrate is presented. Some effects of annealing on the elemental distribution across the Ga"2O"3/GdGaO oxide layer are described. The paper also discusses the analysis of the interface GaAs/Ga"2O"3/GGO at a sub-nm level by high-resolution HAADF STEM imaging.
Real life challenges in access-control management
Authors: Lujo Bauer, Lorrie Faith Cranor, Robert W. Reeder, Michael K. Reiter, Kami Vaniea
Venue: Proceedings of the 27th international conference on Human factors in computing systems (2009)

In this work we ask the question: what are the challenges of managing a physical or file system access-control policy for a large organization? To answer the question, we conducted a series of interviews with thirteen administrators who manage access-control policy for either a file system or a physical space. Based on these interviews we identified three sets of real-world requirements that are either ignored or inadequately addressed by technology: 1) policies are made/implemented by multiple people; 2) policy makers are distinct from policy implementers; and 3) access-control systems don't always have the capability to implement the desired policy. We present our interview results and propose several possible solutions to address the observed issues.
The enumeration of permutations sortable by pop stacks in parallel
Authors: Rebecca Smith, Vincent Vatter
Venue: Information Processing Letters (2009)

We show that the set of permutations sortable by k pop stacks in parallel has a regular insertion encoding and construct the (finite) recognizing automaton for this language. This shows that these permutations have a rational generating function, verifying a conjecture of Atkinson and Sack.
The development facility approach to improved software development
Authors: David W. Johnson
Venue: Proceedings of the May 4-7, 1981, national computer conference (1981)

The use and benefits of a software development facility (SDF) within an organization are reviewed. A generalized SDF framework is presented which suggests the need for a common SDF "kernel" which an organization may tailor and supplement to meet its specific application development needs. The development of a SDF prototype within a particular software development environment is described. Finally, some experiences with the use of the prototype are discussed.
Qualitative findings of students' perception on practice of self-regulated strategies in online community discussion
Authors: Vighnarajah, Su Luan Wong, Kamariah Abu Bakar
Venue: Computers Education (2009)

With rapid emergence to the birth of the knowledge era, an active and interactive learning environment is fundamental to any teaching and learning process. Over time, negative implications of traditional learning environment are mounting, and measures must be taken to challenge it. With extensive research on available learning tools, it has become more feasible to provide our students with better learning opportunities. Such was the anticipation in the Malaysian educational context. Hence, this paper aims to address qualitative findings of a study on self-regulated learning strategies conveyed through the proposed interactive e-learning community (iELC). In duration of eight weeks, students (n=50) from regular national secondary schools were subjected to online learning tasks aimed to advance strategies on self-regulated learning. To date, strategies of self-regulated learning have been perceived as key to learner to succeed academically and after the schooling years. By means of semi-structured interview, data were collected from small group and one-to-one perception. Results were directed at the overall development of self-regulated learning strategies and its diffusion in the iELC discussion platform. Conclusively, these findings add significantly to the understanding of self-regulated learning strategies in an online learning environment.
SLA-Driven Business Process Distribution
Authors: Faramarz Safi Esfahani, Masrah Azrifah Azmi Murad, Md. Nasir Sulaiman, Nur Izura Udzir
Venue: Proceedings of the 2009 International Conference on Information, Process, and Knowledge Management (2009)

Service Oriented Architecture (SOA) includes several building blocks among which orchestration engine demands special attention. Although, there are a number of centralized orchestration engines to execute business processes described by BPEL language in SOA, you may find several decentralized orchestration engines and their purpose is to decompose a BPEL process to several software agents to improve some quality factors. On one hand, choosing a suitable method of process distribution may result in better adaptability of process with run-time environment. On the other hand, in the new generation of Service Oriented Architecture (SOA), Service Level Agreements (SLAs) are of paramount important. We need to have a run-time environment to improve the adaptability of run-time environment with SLAs. Thus, this paper we are going to to combine process distribution methods and SLAs. To reach this goal, firstly, we introduce an intelligent method of using process mining for business process distribution (IPD). Secondly, we compare different methods of processes distribution including Fully, Semi and Intelligent Process Distribution methods. We also show the comparison of these methods considering quality factors such as Total Execution Time, Band Width Usage, Agent Granularity, Resource Adaptability, Memory Usage of Agents, Number of Produced Agents and Total System Adaptability. Thirdly, we consider all of the distribution methods from an SLA view through which users can determine their requirements of executing business processes to be mapped to run-time environment.
Pricing display ads and contextual ads: Competition, acquisition, and investment
Authors: Yung-Ming Li, Jhih-Hua Jhang-Li
Venue: Electronic Commerce Research and Applications (2009)

Most websites are simultaneously supported by display advertising and contextual advertising. In this paper, we develop an economic model to examine the profitability of these two ad types in both a monopolistic market and duopolistic market, identifying the influence of impression benefit and click benefit. We find that in the duopolistic market a rival channel's professional ability to enhance a visitor's impression is beneficial to the channel offering contextual advertising. We also find that the strength of a search engine is limited in the duopolistic market; therefore, acquisition becomes a prime strategy to reveal the value of contextual advertising.
Model-Based Development of firewall rule sets: Diagnosing model inconsistencies
Authors: S. Pozo, R. Ceballos, R. M. Gasca
Venue: Information and Software Technology (2009)

The design and management of firewall rule sets is a very difficult and error-prone task because of the difficulty of translating access control requirements into complex low-level firewall languages. Although high-level languages have been proposed to model firewall access control lists, none has been widely adopted by the industry. We think that the main reason is that their complexity is close to that of many existing low-level languages. In addition, none of the high-level languages that automatically generate firewall rule sets verifies the model prior to the code-generation phase. Error correction in the early stages of the development process is cheaper compared to the cost associated with correcting errors in the production phase. In addition, errors generated in the production phase usually have a huge impact on the reliability and robustness of the generated code and final system. In this paper, we propose the application of the ideas of Model-Based Development to firewall access control list modelling and automatic rule set generation. First, an analysis of the most widely used firewall languages in the industry is conducted. Next, a Platform-Independent Model for firewall ACLs is proposed. This model is the result of exhaustive analysis and of a discussion of different alternatives for models in a bottom-up methodology. Then, it is proposed that a verification stage be added in the early stages of the Model-Based Development methodology, and a polynomial time complexity process and algorithms are proposed to detect and diagnose inconsistencies in the Platform-Independent Model. Finally, a theoretical complexity analysis and empirical tests with real models were conducted, in order to prove the feasibility of our proposal in real environments.
Multi-echelon supply chain simulation using metamodel
Authors: Laigang Song, Xueping Li, Alberto Garcia-Diaz
Venue: Proceedings of the 40th Conference on Winter Simulation (2008)

Metamodels are abstractions of the simulation model that expose the system's input-output relationship through simple mathematical expression (Santos and Santos 2007). It provides an analytical way to study the behavior of a complex system. Multi-echelon supply chain are one of the complex systems. It is hard if not impossible to draw close-form analytical solutions due to the complexities of inventory system and the underlying uncertainty. In this paper, we will apply the methodology of simulation metamodel to a multi-echelon supply chain problem and make statistically analysis of the parameters. The model is validated using training experiment conditions.
Reversible Quantization-Index Modulation Using Neighboring Correlation
Authors: Chin-Chen Chang, Wen-Chuan Wu
Venue: Proceedings of the 6th International Workshop on Digital Watermarking (2008)

In this paper, a novel reversible data hiding scheme, which can recover the original information without any distortions after the hidden secret data have been extracted, based on quantization-index modulation (QIM) technique is presented. This proposed scheme utilizes the local spatial correlation of neighboring quantized VQ indices to conceal secret data under image coded stream and achieve data reversibility simultaneously. As for some not-well-correlated indices, this embedding system burdens the quantized codes with additional indicators for the hereafter recovery. Experimental results proved that the proposed scheme is well furnished with the lossless recovery facility than other QIM-based data hiding schemes.
Proceedings of the 14th ACM SIGPLAN symposium on Principles and practice of parallel programming
Venue: Principles and Practice of Parallel Programming (2009)

It is our great pleasure to welcome you to the 14th ACM SIGPLAN Symposium on Principles and Practice of Parallel Programming (PPoPP'09). Since its inception (as PPEALS) in 1988, PPoPP has served as a leading forum for research in all aspects of parallel software, including theoretical foundations, programming models, algorithms, applications, and systems software. These topics have now moved to center stage in their relevance to mainstream computing, as parallelism becomes ubiquitous with the widespread adoption of homogeneous and heterogeneous multicore processors. This year's call attracted 109 paper submissions, which is a record for PPoPP. Each paper was read by at least three members of the program committee, and additional external reviews were solicited when needed. At an in-person meeting of the program committee in October 2008, 26 papers were selected for presentation at the conference that spanned a broad range of software topics (languages, compilers, tools, runtimes) for a diversity of hardware platforms (multicore, accelerators, and high end computing). Authors of high quality submissions that could not be accepted as full papers were invited to present their work as posters. 14 of 20 accepted this invitation; 2 other posters were chosen from among 6 poster submissions. Following last year's successful co-location with the International Symposium on High-Performance Computer Architecture (HPCA) as back-to-back events, the PPoPP and HPCA conference committees decided to go one step further in 2009 and co-locate the conferences in both space and time as a single federated event. As a result, attendees of one conference have the option of attending talks at another conference, and a number of events (two keynotes, two panels, a poster session, and the conference excursion) have been scheduled as shared events. Given the significance of software-hardware co-design in addressing future research challenges in parallel systems, we hope that this coordination of PPoPP and HPCA will foster greater interaction between the two communities. In addition, our hope is that this overlap will strengthen participation in the workshops and tutorials that preceded both conferences, including the 4th ACM SIGPLAN Workshop on Transactional Computing (TRANSACT 2009).
Gray codes for non-crossing partitions and dissections of a convex polygon
Authors: Clemens Huemer, Ferran Hurtado, Marc Noy, Elsa Omaña-Pulido
Venue: Discrete Applied Mathematics (2009)

In this paper we develop Gray codes for two families of geometric objects: non-crossing partitions and dissections of a convex polygon by means of non-crossing diagonals.