The Scope of Supreme Court Review in Obscenity Cases

Performance of many P2P systems depends on the ability  to construct a ran- dom overlay network among the nodes. Current state-of-the-art techniques for constructing random overlays have an implicit  requirement that any two nodes in the system should always be able to communicate and establish a link be- tween them.  However, this is not the case in some of the environments where distributed systems are required to be deployed,  e.g, Decentralized Online So- cial Networks, Wireless networks, or networks with limited connectivity because of NATs/firewalls,  etc. In such restricted networks, every node is able to com- municate with only a predefined set of nodes and thus, the existing solutions for constructing random overlays are not applicable.In this thesis we propose a gossip based peer sampling service capable of running on top of such restricted networks and producing an on-the-fly random overlay.  The service provides ev- ery participating node with a set of uniform random nodes from the network, as well as efficient routing paths for reaching those nodes via the restricted net- work. We perform extensive experiments on four real-world networks and show that  the resulting overlays rapidly converge to random overlays. The results also exhibit that the constructed random overlays have self healing behaviour under churn and catastrophic failures

Multi-domain service orchestration over networks and clouds: a unified approach

End-to-end service delivery often includes transparently inserted Network Functions (NFs) in the path. Flexible service chaining will require dynamic instantiation of both NFs and traffic forwarding overlays. Virtualization techniques in compute and networking, like cloud and Software Defined Networking (SDN), promise such flexibility for service providers. However, patching together existing cloud and network control mechanisms necessarily puts one over the above, e.g., OpenDaylight under an OpenStack controller. We designed and implemented a joint cloud and network resource virtualization and programming API. In this demonstration, we show that our abstraction is capable for flexible service chaining control over any technology domain

Evaluating the role of aggregate gradation on cracking performance of asphalt concrete for thin overlays

Thin asphalt concrete overlays are a maintenance technique that mainly restore the functional properties of pavements. One of the main issues in thin overlays is reflective cracking that can cause early deterioration and reduce their service life. For this reason, the purpose of this investigation is to evaluate the effect of material selection on cracking performance of asphalt concrete mixtures for thin overlays. In particular, this paper evaluates the role of aggregate skeleton gradation. The study of the effect of aggregate gradation was divided into two stages: (1) fine fraction content and (2) maximum nominal aggregate size. Based on this, up to seven asphalt mixture gradations were designed and evaluated through the Fénix test at different test temperatures. The results showed a significant correlation between the fine fraction content, and maximum nominal aggregate size, and the cracking performance of the asphalt concrete mixtures. Mixtures manufactured with a low content of fine aggregates, as well as small nominal maximum size, experienced a further improvement of their toughness. These results reflected the importance of considering not only the effect of asphalt binder and environmental conditions but also aggregate gradation in the design of asphalt concrete mixtures in order to achieve a desirable cracking performance.Peer ReviewedPostprint (published version

Performance evaluation and construction design of concrete overlays

Concrete overlays extend the service life of existing pavement and are potentially one of the most cost-effective maintenance and rehabilitation strategies for pavement systems. While concrete overlays are not new, the long-term performance of various types of concrete overlays has not been fully investigated because there has been insufficient performance data available to support such evaluation. The Iowa Pavement Management Program (IPMP), the Iowa Concrete Paving Association (ICPA), and other agencies have created a complete concrete overlays historical performance database, and this historical performance database includes the Pavement Condition Index (PCI), the International Roughness Index (IRI), overlay type, construction year, overlay thickness, joint spacing, traffic, and other construction and design-related data over a 30-year period. This study included more than 300 overlay projects based on more than 1,400 miles of roadway to evaluate the long-term performance of concrete overlays. The main purpose of this study is to evaluate the long-term performance trend concrete overlays. The effects of overlay type and design features (thickness and joint spacing) on long-term performance were also identified. The effects of structural design alternatives on concrete overlay performance have been identified using the latest version of AASHTOWare Pavement ME Design (Version 2.3.1). Furthermore, to develop and practical ANN model for predicting concrete overlay performance based on historical performance database. In addition, investigating differences in behavior between shorter joint spacing and conventional joint spacing for optimize concrete overlays joint spacing size. Long-term performance trends can be evaluated by studying PCI and IRI (two measures representative of pavement performance) changes during pavement service life. Performance data dating back to 1998 for all in-service Iowa concrete overlays constructed over the last 38 years were collected and evaluated. To date, since concrete overlays do not reflect new technology, and concrete overlay design procedures still follow empirical methods, this study applied both mechanistic-empirical design software and machine-learning techniques (i.e. AASHTOWare Pavement ME Design (Version 2.3.1) and Artificial Neural Networks (ANN) model) to identify the effects of various design parameters and help in predicting concrete overlay service life. AASHTOWare Pavement ME Design (Version 2.3.1) is a powerful software package able to simulate alternative joint spacing design options on various types of concrete overlays, and it provides theoretical insights for developing recommendations for pavement design. An ANN model is a machine learning tool that has been successfully used in the field of pavement design and analysis. Compared with other statistical techniques, since the deterioration of pavement performance is a non-linear function, the ANN model has shown superior accuracy for pavement management systems. Four different groups (distress data, construction design data, traffic data, and climate data) of input variables were used to predict pavement performance in the ANN model. Non-destructive testing (NDT) is another method for identifying the effects of various design parameters in concrete overlay systems. In this study, ultrasonic low-frequency tomography (MIRA) proved effective in detecting whether a saw-cut was activated. By comparing joint activation results with slab length values and radius of relative stiffness ratio (L/ℓ), recommendations on joint spacing for Iowa concrete overlays were developed. Results from a summary of long-term performance showed that concrete overlays can extend service life of existing pavement by at least 20 years. After a comprehensive review of concrete overlay performance data, the adequate and substandard performance data were identified, showing differences between adequate and substandard performance over a 10-year service life, and indicating that improving construction quality to eliminate premature failure can also increase concrete overlay service life. In additional, compared to historical performance-related data, the Pavement ME Design software results is conservative in predicting concrete overlay service life. On the other hands, according to the concrete overlays prediction models results, the ANN model resulted in a root mean squared error (RMSE) of less than 10% of the range of IRI values, indicating that the ANN model was successful in predicting Iowa concrete overlay performance. Compared with MIRA evaluate rates of joint activation results and slab length values and radius of relative stiffness ratio (L/ℓ), joint spacing should be based on L/ℓ value between 4 and 7

GRIDKIT: Pluggable overlay networks for Grid computing

A `second generation' approach to the provision of Grid middleware is now emerging which is built on service-oriented architecture and web services standards and technologies. However, advanced Grid applications have significant demands that are not addressed by present-day web services platforms. As one prime example, current platforms do not support the rich diversity of communication `interaction types' that are demanded by advanced applications (e.g. publish-subscribe, media streaming, peer-to-peer interaction). In the paper we describe the Gridkit middleware which augments the basic service-oriented architecture to address this particular deficiency. We particularly focus on the communications infrastructure support required to support multiple interaction types in a unified, principled and extensible manner-which we present in terms of the novel concept of pluggable overlay networks

A component-based middleware framework for configurable and reconfigurable Grid computing

Significant progress has been made in the design and development of Grid middleware which, in its present form, is founded on Web services technologies. However, we argue that present-day Grid middleware is severely limited in supporting projected next-generation applications which will involve pervasive and heterogeneous networked infrastructures, and advanced services such as collaborative distributed visualization. In this paper we discuss a new Grid middleware framework that features (i) support for advanced network services based on the novel concept of pluggable overlay networks, (ii) an architectural framework for constructing bespoke Grid middleware platforms in terms of 'middleware domains' such as extensible interaction types and resource discovery. We believe that such features will become increasingly essential with the emergence of next-generation e-Science applications. Copyright (c) 2005 John Wiley & Sons, Ltd