Language Convergence Infrastructure

The process of grammar convergence involves grammar extraction and transformation for structural equivalence and contains a range of technical challenges. These need to be addressed in order for the method to deliver useful results. The paper describes a DSL and the infrastructure behind it that automates the convergence process, hides negligible back-en

Guided Grammar Convergence. Full Case Study Report. Generated by converge::Guided

This report is meant to be used as auxiliary material for the guided grammar convergence technique proposed earlier as problem-specific improvement in the topic of convergence of grammars. It contains a narrated MegaL megamodel, as well as full results of the guided grammar convergence experiment on the Factorial Language, with details about each grammar source packaged in a readable form. All formulae used within this document, are generated automatically by the convergence infrastructure in order to avoid any mistakes. The generator source code and the source of the introduction text can be found publicly available in the Software Language Processing Suite repository

An Alloy Verification Model for Consensus-Based Auction Protocols

Max Consensus-based Auction (MCA) protocols are an elegant approach to establish conflict-free distributed allocations in a wide range of network utility maximization problems. A set of agents independently bid on a set of items, and exchange their bids with their first hop-neighbors for a distributed (max-consensus) winner determination. The use of MCA protocols was proposed, $e.g.$, to solve the task allocation problem for a fleet of unmanned aerial vehicles, in smart grids, or in distributed virtual network management applications. Misconfigured or malicious agents participating in a MCA, or an incorrect instantiation of policies can lead to oscillations of the protocol, causing, $e.g.$, Service Level Agreement (SLA) violations. In this paper, we propose a formal, machine-readable, Max-Consensus Auction model, encoded in the Alloy lightweight modeling language. The model consists of a network of agents applying the MCA mechanisms, instantiated with potentially different policies, and a set of predicates to analyze its convergence properties. We were able to verify that MCA is not resilient against rebidding attacks, and that the protocol fails (to achieve a conflict-free resource allocation) for some specific combinations of policies. Our model can be used to verify, with a "push-button" analysis, the convergence of the MCA mechanism to a conflict-free allocation of a wide range of policy instantiations

Recovering Grammar Relationships for the Java Language Specification

Grammar convergence is a method that helps discovering relationships between different grammars of the same language or different language versions. The key element of the method is the operational, transformation-based representation of those relationships. Given input grammars for convergence, they are transformed until they are structurally equal. The transformations are composed from primitive operators; properties of these operators and the composed chains provide quantitative and qualitative insight into the relationships between the grammars at hand. We describe a refined method for grammar convergence, and we use it in a major study, where we recover the relationships between all the grammars that occur in the different versions of the Java Language Specification (JLS). The relationships are represented as grammar transformation chains that capture all accidental or intended differences between the JLS grammars. This method is mechanized and driven by nominal and structural differences between pairs of grammars that are subject to asymmetric, binary convergence steps. We present the underlying operator suite for grammar transformation in detail, and we illustrate the suite with many examples of transformations on the JLS grammars. We also describe the extraction effort, which was needed to make the JLS grammars amenable to automated processing. We include substantial metadata about the convergence process for the JLS so that the effort becomes reproducible and transparent

How is Convergence Best Achieved in International Project Finance?

This Essay will first review and then analyze the characteristics of each of three possible routes of convergence in light of three features. The first is stability and predictability of the legal environment. It is the main benefit that private investors look for before investing in a country. The second is the scope of influence and lobbying of interest groups. This feature is extracted from an analysis of the adoption of uniform laws proposed by the National Conference of Commissioners on Uniform State Laws ( NCCUSL ) by Professors Ribstein and Kobayashi. These authors find evidence of enactment by states of NCCUSL\u27s proposals despite a cost-benefit analysis suggesting that these proposals are not efficient. This inefficiency results from the influence of interest groups and NCCUSL\u27s reliance on ill-informed generalists. The third feature is the respect for, or promotion of, public interest considerations. This analysis may reveal a tension between the economic efficiency and the social desirability of these routes, between market-driven policy and public interest concerns. This tension plays out in different ways. The more commonly addressed conflicts of interests are between public players and private investors; between (1) the interests of the host country in obtaining adequate financial and technical safeguards and assurances from the private participants that the project will be carried out safely, on time, and in the public interest and (2) the interests of private participants in limiting the type and number of guarantees that they give. The less explored tension addresses the respect for standards, such as human rights standards, that the host country itself may be reluctant to promote, but that affect private investment in terms of reputation or expense. This Essay disregards the tension between economic efficiency and social desirability, and rather focuses on the goal of reconciling private and public interest concerns. It will seek to determine whether one of these routes is better than the others, or whether a combination of the three is the best way to achieve convergence in international project finance. In conclusion, this Essay will show that all three routes to convergence are necessary to both foster and control international project finance. The twin goals of balancing private and public interests are best fulfilled at the international level, since this level can generate clear, balanced, and uniform rules by promulgating a suitable model law yet to be prepared. State initiative is then required to enact these rules and adapt them to domestic specificities. The establishment of a legal framework at the state level should be general and flexible enough not to suffocate private initiative since the latter brings innovation and evolution of norms in project finance. No one route can therefore be preferred over any other. If one is used alone, it is more likely to be inefficient

Building consensus on Internet access at the Internet Governance Forum (IGF)

This paper identifies and documents the main areas of discussions and 'recommendations' that were generated under the Access theme at the second Internet Governance Forum in Rio De Janeiro, November 2007. Whilst recognising that the IGF is currently viewed and operates primarily as a space for discussion, the paper finds that (specifically in the case of Access) it is also a space in which commonality of opinion occurs to the level at which 'recommendations' can be made and repeatedly asserted independently/individually in the workshops, and strategically reinforced at different levels of the IGF. The Internet Governance Forum (IGF) is a space for multi-stakeholder policy dialogue, set up in 2006 as a direct response to the deliberations of the World Summit on the Information Society (WSIS). The forum was created to (amongst other things) discuss public policy issues related to key elements of internet governance in order to foster the sustainability, robustness, security, stability and development of the internet. Its structure, function and working are addressed in paragraphs 73 to 79 of the WSIS Tunis Agenda

Wireless Play and Unexpected Innovation

Part of the Volume on Digital Young, Innovation, and the Unexpected. This chapter considers play as leading to unexpected innovation in advanced wireless technologies. It concludes that much of the potential for new media to enhance innovation actually echoes much older patterns, as evidenced by comparisons to wireless history. These are patterns of privilege, particularly class and gender privilege, reinforced by strict intellectual property protections. Detailed case studies are presented of the "wardrivers," young male computer enthusiasts who helped map wi-fi signals over the past decade, and of earlier analog wireless enthusiasts. The chapter offers a solid critique of many present-day celebrations of technology-driven innovation and of the rhetoric of participatory culture

Asynchronous iterative computations with Web information retrieval structures: The PageRank case

There are several ideas being used today for Web information retrieval, and specifically in Web search engines. The PageRank algorithm is one of those that introduce a content-neutral ranking function over Web pages. This ranking is applied to the set of pages returned by the Google search engine in response to posting a search query. PageRank is based in part on two simple common sense concepts: (i)A page is important if many important pages include links to it. (ii)A page containing many links has reduced impact on the importance of the pages it links to. In this paper we focus on asynchronous iterative schemes to compute PageRank over large sets of Web pages. The elimination of the synchronizing phases is expected to be advantageous on heterogeneous platforms. The motivation for a possible move to such large scale distributed platforms lies in the size of matrices representing Web structure. In orders of magnitude: $10^{10}$ pages with $10^{11}$ nonzero elements and $10^{12}$ bytes just to store a small percentage of the Web (the already crawled); distributed memory machines are necessary for such computations. The present research is part of our general objective, to explore the potential of asynchronous computational models as an underlying framework for very large scale computations over the Grid. The area of ``internet algorithmics'' appears to offer many occasions for computations of unprecedent dimensionality that would be good candidates for this framework.Comment: 8 pages to appear at ParCo2005 Conference Proceeding