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92,314 results · page 3767 of 3,847
Alfredo De Santis, Giovanni Di Crescenzo, Giuseppe Persiano
No abstract is available for this record.
Peng Xu, Ralph Deters
Despite the considerable efforts spent on researching and developing Multi-Agent Systems (MAS) there is a noticeable absence of deployed systems. In the past the MAS research community ignored this problem - arguing that it is not a genuine MAS problem and consequently of lesser importance than other unsolved issues like cooperation, coordination, negotiation and communication. However, as the field matures, empirical evaluations of techniques and systems are more commonly used and deployment issues like the management of a MAS become increasingly important. This paper introduces a generic framework for fault-management in MAS that has been successfully tested in a large scale MAS. 1. Motivation MAS are decentralized self-organizing systems consisting of autonomous entities called agents that are designed to solve tasks by cooperating with each other. Using structured messages for communication the agents negotiate and coordinate in a decentralized manner the actions required to solve a common task. Decentralization and self-organization ensure that there is no need for a central coordination and consequently no single point of failure resulting in a more robust design. But with the absence of centralized coordination it becomes difficult to determine the current state of the system or to predict the effects of actions. This difficulty concerning the determination and prediction of states is made worse by the fact that the functional dependencies between the agents change over time as a result of negotiations at run-time. Consequently MAS can appear to behave chaotically, which is one of the reasons for the lack of successful deployments. To overcome these difficulties it is necessary to introduce management functions that will support the monitoring and controlling of individual agents as well as the MAS. ISO/OSI defines five basic management functions for any distributed system namely: accounting management, configuration management, performance management, security management and fault management. While all five are important management functions we view fault management as the most relevant in the deployment of a MAS based on our experiences [1].
Dalu Zhang
A zero-knowledge proof of identity protocol on conic is proposed in this paper.The security of this protocol is based on the discrete logarithm problem on conic over finite fields.These kinds of identity protocols can be designed and implemented easier than those on elliptic curve,and faster than those based on discrete logarithm.Security and feasibility are discussed.A simple solution is proposed to a potential leak of this protocol.
Masayuki Abe, Serge Fehr
Abstract. We propose the first distributed discrete-log key generation (DLKG) protocol from scratch which is adaptively-secure in the nonerasure model, and at the same time completely avoids the use of interactive zero-knowledge proofs. As a consequence, the protocol can be proven secure in a universally-composable (UC) like framework which prohibits rewinding. We prove the security in what we call the singleinconsistent-player UC model, which guarantees arbitrary composition as long as all protocols are executed by the same players. As an application, we propose a fully UC threshold Schnorr signature scheme. Our results are based on a new adaptively-secure Feldman VSS scheme. Although adaptive security was already addressed by Feldman in the original paper, the scheme requires secure communication, secure erasure, and either a linear number of rounds or digital signatures to resolve disputes. Our scheme overcomes all of these shortcomings, but on the other hand requires some restriction on the corruption behavior of the adversary, which however disappears in some applications including our new DLKG protocol. We also propose several new adaptively-secure protocols, which may find other applications, like a sender non-committing encryption scheme, a distributed trapdoor-key generation protocol for Pedersen’s commitment scheme, or distributed-verifier proofs for proving relations among commitments or even any NP relations in general. 1
Cathy S Dove
Many institutions of higher education have an administrative structure that reflects the highly decentralized nature of academic departments. In an era of cost-reductions, many universities are asking the fundamental question “Must the administrative side of the house mirror the academic structure with its many layers and fragmented organization”? While the autonomous and highly decentralized academic structure is a primary driver of the world-class strength of the American research university, the structure does not necessarily support the efficient delivery of routine administrative functions. By conducting administrative work at every level of the institution, many universities are finding their administrative structure is redundant, inefficient and expensive. Today's universities are being challenged to cut costs and focus limited resources on core mission activities of teaching, research and public service. Many are looking to realize these cost reductions in administration functions. The advantage of reducing expenses in administration is that the fundamental strength and nature of the institution can be protected while improving efficiency in the “non-value added” functions. This study examines the applicability to higher education of an organizational model found in many corporations facing similar challenges—the shared service center. The shared service center model consolidates administrative functions into a structure that considers the groups that use the center as “customers”. It is performance and market-driven. This study examines three organizations that have attempted to implement the shared service model. In each case, the impetus for change, the change process itself, and the ability of the model to achieve stated objectives are described and assessed. The study concludes that the shared service model could well be an appropriate administrative structure for higher education, but that the implementation strategy and results may differ from those observed in other industries.
Satoshi NAKANO
In an era in which neo-liberalism has strong societal influences, it seems particularly indispensable to look into the efforts and achievements in Europe to create the social dimension of the integration. Particularly focusing upon the European social dialogue at the macro level, this article depicts its history, function and the challenges it faces.In the main section, the social dialogue at this level is examined in terms of (1) actors, (2) tripartite concertation, (3) consultation according to Articles 137 and 138 of the Treaty and (4) the bipartite, autonomous dialogue between the social partners. With regard to the actors, such problems as the decreasing density and legitimacy of trade union representation in some countries and the lack of a sectoral institution of employers are described, along with some recent organizational developments In the context of the Lisbon strategy adopted in March 2000, the tripartite concertation has taken a significant, albeit embryonic step towards the advent of the corporatist configuration that relates economic and social policies. The consultation processes have created three directives that set minimum standards in the EU. Together with the increasingly autonomous bipartite dialogue that began with a work programme in November 2002, the social dialogue now serves as the driving force of labour market regulation and social integration.Nevertheless, with the national corporatist systems being encroached upon, the European system has been facing some challenges In the last section, its major problems are classified into five categories: the legitimacy of interest representation, the effectiveness of social legislation, dim prospects as a means of macro-economic regulation, the decentralized systems of industrial relations in the CEE countries and an unclear position in the future associational democracy. The European social dialogue may open up a new possibility of formulating innovative policies based on participative democracy that was only available in each member state. Nevertheless, whether or not such a possibility will come true in the near future remains to be seen.
Staffan Stranne
The main research questions for this local study of Tarkett AB, a floor manufacturer, are based on the central characteristics of the third industrial revolution: globalization, technological development, and organizational change. As a background to the local development and change towards the end of the twentieth century, I have chosen to emphasize, on the one hand, the increasing need of the industry for internationalization, rationalization, and productivity development after fordism and the demise of the regulated “real wages capitalism” in the middle of the 1970s, and, on the other, the work rights offensive of the labor movement in the 1970s and its continued struggle for economic and industrial authority. The method to analyze the essential traits of the organizational change process has aimed to construe a field of organizational change whose ideal types are based on taylorism, toyotism, flexible specialization, just-in-time, and lean production. Methods used to analyze change from the perspective of social structuration are also related to the theories of dynamic contradictory class locations, local hegemony, and gender. Apart from traditional source material and interviews, the study builds on the results from a study group consisting of a number of factory workers from Tarkett. Technological change and development (IT) of the work process on the factory floor has been analyzed as technological rationalization, quality development, work environment improvement, and as issues of gender relations and class positions at the work place. As regards the management process, leadership and control, centralization and decentralization concepts are vital. In matters concerning working conditions, including salaries, working hours, and job profiles (qualifications required for employment) are central. The management process was subject to changes that entailed deviations from the principles of traditional tayloristic management philosophy. Instead a participant change strategy implemented decentralized leadership functions in the shape of management by objectives via autonomous groups according to principles of ”responsible autonomy”. The investigation shows that computer-aided centralized control functions, competence improvement, and intensified ideological control worked together to change the management process. Decentralization of responsibility, the integration of white-collar like duties, the general competence development, and the higher demands on job qualifications, combined to render workers’ class locations more contradictory. This, together with ideological control and change, contributed to consolidate local hegemony.
Arshad Ali, A. Anjum, Tahir Azim, M. Thomas · 9 authors
In this paper we describe JClarens; a Java based implementation of the Clarens remote data server. JClarens provides Web services for an interactive analysis environment to dynamically access and analyze the tremendous amount of data scattered across various locations. Additionally this research is aimed to develop a service oriented grid enabled portal (GEP) that provides interface and access to several grid services to give a homogeneous and optimized view of the distributed and heterogeneous environment. Other than showing platform independent behavior provided by Java, the use of XML-RPC based Web services enabled JClarens to be a language neutral server and demonstrated interoperability with its Python variant. Extreme care has been taken in the usage and manipulation of various Java libraries to cater the needs of high performance computing. The overall exercise has yielded in a prototype with strong emphasis on security and virtual organization management (VOM). This shall provide a common platform to support development of larger, more flexible framework with future aims to integrate it with a loosely coupled, decentralized, and autonomous framework for grid enabled analysis environment (GAE).
Ning Chen, Jiawei Rong
Interactive proof and zero-knowledge proof systems are two important concepts in cryptography and complexity theory. In the past two decades, a great number of interactive proof and zero-knowledge proof protocols have been designed and applied in practice. In this paper, a simple memorizable zero-knowledge protocol is proposed for graph non-isomorphism problem, based on the memorizable interactive proof system,which is extended from the original definition of interactive proof and is more applicable in reality.
Ronald Cramer, Ivan Damgård
No abstract is available for this record.
Mark Gradstein, Moshe Justman, Volker Meier
The dominant role played by the state in the financing, regulation, and provision of primary and secondary education reflects the widely-held belief that education is necessary for personal and societal well-being. The economic organization of education depends on political as well as market mechanisms to resolve issues that arise because of contrasting views on such matters as income inequality, social mobility, and diversity. This book provides the theoretical framework necessary for understanding the political economy of education -- the complex relationship of education, economic growth, and income distribution -- and for formulating effective policies to improve the financing and provision of education. The relatively simple models developed illustrate the use of analytical tools for understanding central policy issues. After offering a historical overview of the development of public education and a review of current econometric evidence on education, growth, and income distribution, the authors lay the theoretical groundwork for the main body of analysis. First they develop a basic static model of how political decisions determine education spending; then they extend this model dynamically. Applying this framework to a comparison of education financing under different regimes, the authors explore fiscal decentralization; individual choice between public and private schooling, including the use of education vouchers to combine public financing of education with private provision; and the social dimension of education -- its role in state-building, the traditional "melting pot" that promotes cohesion in a culturally diverse society.
Erik Wibbels, Jonathan Rodden
Empirical studies have determined that tax-transfer programs pursued by central governments in decentralized federations provide modest insurance against asymmetric regional income shocks, but this paper hypothesizes that pro-cyclical fiscal policy among provincial governments can easily overwhelm any such stabilizing effect. I examine the cyclicality of revenues, grants, expenditures, and deficits among provincial governments in seven federations since the 1970s, showing that in most cases, fiscal policy among the constituent units appears to be pro-cyclical by design. Own-source taxes are highly pro-cyclical in all federations, and contrary to common wisdom, revenue-sharing and discretionary transfers are either acyclical or even pro-cyclical. Constituent governments are thus left alone to smooth their own shocks, even though various restraints on borrowing and saving often undermine their ability to do so. These results have important implications for debates about fiscal arrangements being considered by member states in the European Union.
Francisco Matias Cuenca-Acuna, Thu D. Nguyen
We consider the problem of deploying and managing federated services that run on federated systems spanning multiple collaborative organizations. In particular, we present a peer-to-peer framework targeted to the construction of self-managing services that automatically adjust the number of service components and their placements in response to changes in the system or client loads. Our framework is completely decentralized, depending only on a modest amount of loosely synchronized global state. More specifically, our framework is comprised of a set of per-node monitoring agents and per-service-component management agents that periodically exchange information about the state of the system and of the service with each other using a gossiping protocol. Each management agent then periodically searches for configurations that are better than the current one according to an application model and explicit performance and availability targets. On finding a better configuration, an agent will enact the new configuration after a random delay to avoid possible collisions. We evaluate our framework by studying a prototype UDDI service. We show that while agents act autonomously, the service rapidly reaches a stable and appropriate configuration in response to system dynamics.
美博 三宅, Yoshihiro Miyake
No abstract is available for this record.
Rafail Ostrovsky, Charles Rackoff, Adam Smith
No abstract is available for this record.
Richard Sabey
The cipher (or athbash, under which name Web3 defines it) is a Hebrew substitution cipher which replaces the first letter of the Hebrew alphabet (aleph, 1\) by the last (tav, ) the second (beth, J) by the last but one (shin, IJI), and so on, unti I we get to the last (ta , n), which i replaced by the first (aleph, 1\). Jan Anderson described it in Fledge Ledge Edge (WW 8. 1997229). Naturally, the idea can be applied to our alphabet; following the precedent set by atbash I name it the azby cipher.
Boaz Barak, Rafael Pass
No abstract is available for this record.
Deniz Erdoğmuş, José C. Prı́ncipe, Rajvignesh Thogulua
No abstract is available for this record.
Luo Wen
In the paper, we present a notion about two directional zero knowledge proof, and study the relation between two directional zero knowledge proof and traditional one directional zero knowledge proof. We propose several simple two directional zero knowledge problem proof protocols. We introduce the two directional zero knowledge proof is to study secure multi party computation. Based on the two directional zero knowledge, we have designed some special function secure two party computation protocols, including exponential function problem, power function problem, logarithmic function problem, trigonometric function problem, and propose some concern protocols.
Aggelos Kiayias, Yiannis Tsiounis, Moti Yung
No abstract is available for this record.
Boaz Barak, Yehuda Lindell, Salil Vadhan
We show new lower bounds and impossibility results for general (possibly non-black-box) zero-knowledge proofs and arguments. Our main results are that, under reasonable complexity assumptions: 1. There does not exist a two-round zero-knowledge proof system with perfect completeness for an NP-complete language. The previous impossibility result for two-round zero knowledge, by Goldreich and Oren (J. Cryptology, 1994) was only for the case of auxiliary-input zero-knowledge proofs and arguments. 2. There does not exist a constant-round zero-knowledge strong proof or argument of knowledge (as defined by Goldreich (2001)) for a nontrivial language. 3. There does not exist a constant-round public-coin proof system for a nontrivial language that is resettable zero knowledge. This result also extends to bounded-resettable zero knowledge, in which the number of resets is a priori bounded by a polynomial in the input length and prover-to-verifier communication.
Rosario Manasan
Twelve years into the implementation of the Local Government Code of 1991, it is but opportune to assess how the key features of this landmark legislation has contributed to (or detracted from) achieving the balance between local autonomy and accountability. The literature on fiscal decentralization suggests that these two goals are not incompatible. In fact, real autonomy (in the sense of subnational governments being able to link their spending decisions with their revenue/tax decisions) promotes fiscal responsibility. In the context of the ongoing debate in the Philippines, however, local autonomy has been equated (by many LGUs officials) with the independence of LGUs from central government interference. As such, LGU officials have focused more on securing even higher levels of block grants in order to address the widely perceived vertical fiscal imbalance. However, closer scrutiny of the problem indicates that greater_x000D_ tax decentralization coupled with a well designed intergovernmental transfer system that includes elements of fiscal equalization and categorical grants conditional on the achievement of minimum service standards would better enhance the gains that are forthcoming from the decentralization process while minimizing the risks of macroinstability.
Georgia Koloniari, Evaggelia Pitoura
No abstract is available for this record.
Shangping Wang
Zero-knowledge proof schemes of possessing a RSA digital signature are proposed. The schemes give a new method of preventing arbitrary propagation of digital signature. By which the prover does not need to give directly the signature of the message, but to give a zero-knowledge proof of possessing a digital signature. The schemes are the improvement of confirm signature, and is much simpler in practice and of significant feature that it does not need the third party to take part in the scheme. The schemes can be used in copyright protection.