An Enhanced Bully Algorithm for Electing a Coordinator in Distributed Systems

In a distributed system for accomplishing a large complex task, the task is divided into subtask and distributed among processes and coordination among processes done via message passing. To make proper coordination and functioning we need a leader node or coordinator node which acts as a centralized control node. Leader election is the most challenging task in distributed system because it is not necessary that leader node is always same because of crash failure or out of service may occur in the system. Tremendous algorithms have been proposed for elect the new leader. These algorithms use a different technique to elect a leader in distributed system. Bully election algorithm is one of the traditional algorithms for electing a leader, in which the highest node Id is elected as a leader but this algorithm requires lots of message passing for electing a leader that imposes heavy network traffic. Due to heavy network traffic, it creates complexity in message passing and takes more time. In this paper, we introduce a new approach which overcomes the drawback of existing Bully election algorithm. Our proposed algorithm is an enhanced version of Bully election algorithm. Our analytical result shows that our algorithm is more efficient than original Bully Algorithm

Improved bully election algorithm for distributed systems

Electing a leader is a classical problem in distributed computing system. Synchronization between processes often requires one process acting as a coordinator. If an elected leader node fails, the other nodes of the system need to elect another leader without much wasting of time. The bully algorithm is a classical approach for electing a leader in a synchronous distributed computing system, which is used to determine the process with highest priority number as the coordinator. In this paper, we have discussed the limitations of Bully algorithm and proposed a simple and efficient method for the Bully algorithm which reduces the number of messages during the election. Our analytical simulation shows that, our proposed algorithm is more efficient than the Bully algorithm with fewer messages passing and fewer stages

Monopolies, Monopsonies, and Everything In-Between: The Gradual Unwinding of Nearly a Century of Antitrust Activity

Changes in the interpretation of antitrust law since the Reagan administration have created a simultaneous increase in mergers/acquisitions and a decrease in antitrust action. This trend started with Ronald Reagan in an effort to bolster a stagnant United States economy, yet in spite of the revolution the global economy has undergone in the last few decades, this trend is still perpetuated today. While this has helped the United States economy abroad, it has come at a cost domestically. A number of industries have become dominated by a single firm (or a group) through a variety of anticompetitive practices, and their continued dominance threatens consumer welfare. Industries singled out as “ripe for antitrust action” include agricultural seed (Monsanto / Bayer AG), insulin production (Eli Lilly, Novo Nordisk, and Sanofi), eyewear (EssilorLuxottica), and social media (Meta)

NETWORKED MICROGRID OPTIMIZATION AND ENERGY MANAGEMENT

Military vehicles possess attributes consistent with a microgrid, containing electrical energy generation, storage, government furnished equipment (GFE), and the ability to share these capabilities via interconnection. Many military vehicles have significant energy storage capacity to satisfy silent watch requirements, making them particularly well-suited to share their energy storage capabilities with stationary microgrids for more efficient energy management. Further, the energy generation capacity and the fuel consumption rate of the vehicles are comparable to standard diesel generators, for certain scenarios, the use of the vehicles could result in more efficient operation. Energy management of a microgrid is an open area of research especially in generation constrained scenarios where shedding of low-priority loads may be required. Typical metrics used to assess the effectiveness of an energy management strategy or policy include fuel consumption, electrical storage energy requirements, or the net exergy destruction. When considering a military outpost consisting of a stationary microgrid and a set of vehicles, the metrics used for managing the network become more complex. For example, the metrics used to manage a vehicle’s onboard equipment while on patrol may include fuel consumption, the acoustic signature, and the heat signature. Now consider that the vehicles are parked at an outpost and participating in vehicle-to-grid power-sharing and control. The metrics used to manage the grid assets may now include fuel consumption, the electrical storage’s state of charge, frequency regulation, load prioritization, and load dispatching. The focus of this work is to develop energy management and control strategies that allow a set of diverse assets to be controlled, yielding optimal operation. The provided policies result in both short-term and long-term optimal control of the electrical generation assets. The contributions of this work were: (1) development of a methodology to generate a time-varying electrical load based on (1) a U.S. Army-relevant event schedule and (2) a set of meteorological conditions, resulting in a scenario rich environment suitable for modeling and control of hybrid AC/DC tactical military microgrids, (2) the development of a multi-tiered hierarchical control architecture, suitable for development of both short and long term optimal energy management strategies for hybrid electric microgrids, and (3) the development of blending strategies capable of blending a diverse set of heterogeneous assets with multiple competing objective functions. This work could be extended to include a more diverse set of energy generation assets, found within future energy networks

Untangling Defamation Law: Guideposts for Reform

This article, which is based on a keynote address given at the 2023 Missouri Law Review Symposium, addresses the past and predicted future of defamation law in hopes of galvanizing needed reforms. As a necessary backdrop, this article explains why today’s defamation law remains so complex, tracks reforms over the last half century, and explains why the common law of defamation has not adapted adequately to the challenges posed by cheap speech in the digital era. The article then turns to assessing the complaints of defamation law’s most prominent would-be reformers and finds them to rest on an incomplete understanding of how defamation law’s complex pieces contribute to the whole. Finally, after identifying some important barriers to defamation law reform, the article provides guideposts for the reform process

Extensão de propriedades SQL a SGBD NoSQL através de call level interfaces

Mestrado em Engenharia de Computadores e TelemáticaOs arquitetos de software usam ferramentas, tais como Call Level Interfaces (CLI), para guardar, atualizar e retirar dados de Sistemas de Gestão de Bases de Dados (SGBD). Estas ferramentas estão desenhadas para efetuarem a junção entre os paradigmas de Base de Dados Relacional e da Programação Orientada a Objetos e fornecem funcionalidades padrão para interagir com SGBD. No entanto, a emergência do paradigma NoSQL, e particularmente de novos fornecedores de SGBD NoSQL, leva a situações onde algumas das funcionalidades padrão fornecidas por CLI não são suportadas. Isto deve-se normalmente à distância entre o modelo SQL e NoSQL, ou devido a restrições de design. Assim, quando um arquiteto de sistema precisa de evoluir, nomeadamente de um SGBD relacional para um SGBD NoSQL, tem de ultrapassar as dificuldades que emergem por existirem funcionalidades não suportadas pelo SGBD NoSQL. Não só isso, mas as CLI costumam ignorar políticas de controlo de acesso estabelecidas e, portanto, programadores de aplicações têm de dominar as ditas políticas de maneira a desenvolverem software em concordância com elas. Escolher o SGBD NoSQL errado pode levar a problemas de grandes dimensões quando as aplicações pedem funcionalidades não suportadas ou a que não têm acesso. Esta tese foca-se em implementar funcionalidades que não são comummente suportadas por SGBD NoSQL, tais como Stored Procedures, Transações, Save Points e interações com estruturas de memória local, através de uma framework baseada numa CLI padrão. O modelo de implementação de funcionalidades é definido por módulos da nossa framework, e permite a criação de sistemas distribuídos e tolerantes a falhas, que simulam as funcionalidades anteriormente referidas e abstraem as funcionalidades da base de dados subjacente de clientes. Também temos como objetivo integrar a nossa framework com trabalho anterior, a S-DRACA, uma arquitetura dinâmica e segura de controlo de acesso para aplicações relacionais, onde as permissões são definidas como sequências de expressões create, read, update e delete. Com esta integração, conseguimos fornecer Role-Based Access Control e outras funcionalidades de segurança a qualquer tipo de SGBD. Desenvolvemos várias formas de utilizar cada componente (localmente ou distribuído) e a framework está construída de forma modular, o que permite aos vários componentes serem utilizados individualmente ou em grupo, assim como permite o acrescento de funcionalidades ou SGBD adicionais por administradores de sistema que queiram adaptar a framework às suas necessidades particulares.To store, update and retrieve data from database management systems (DBMS), software architects use tools, like call level interfaces (CLI), which provide standard functionality to interact with DBMS. These tools are designed to bring together the relational database and object-oriented programming paradigms, but the emergence of the NoSQL paradigm, and particularly new NoSQL DBMS providers, leads to situations where some of the standard functionality provided by CLI are not supported, very often due to their distance from the relational model or due to design constraints. As such, when a system architect needs to evolve, namely from a relational DBMS to a NoSQL DBMS, he must overcome the difficulties conveyed by the features not provided by the NoSQL DBMS. Not only that, but CLI usually forsake applied access control policies. As such, application developers must master the established policies as a means to develop software that is conformant with them. Choosing the wrong NoSQL DBMS risks major issues with applications requesting non-supported features and with unauthorized accesses. This thesis focuses on deploying features that are not so commonly supported by NoSQL DBMS, such as Stored Procedures, Transactions, Save Points and interactions with local memory structures, through a framework based in a standard CLI. The feature implementation model is defined by modules of our framework, and allows for distributed and fault-tolerant systems to be deployed, which simulate the previously mentioned features and abstract the underlying database features from clients. It is also our goal to integrate our framework with previous work, S-DRACA, a dynamic secure access control architecture for relational applications, where permissions are defined as a sequence of create, read, update and delete expressions. With the integration, we can provide dynamic Role-Based Access Control and other security features to any kind of DBMS. We developed several ways of using each component (locally or distributed) and the framework is built in a modular fashion, which allows several components to be used individually or together, as well as extra features or DBMS to be added by system administrators that wish to adapt the framework to their particular needs

CRISIS IN THE EUROPEAN UNION: THE POLITICS OF INTEGRATION, ENGAGEMENT, AND DISSENT, 2008-2016

This thesis is a comprehensive interpretation of European political history in the periodization from 2008 to 2016. The history begins with an exploration of the intellectual and political origins of the post-World War II project of European integration and the development of, and opposition to, the early institutions that eventually formed the contemporary assemblage of the European Union. Following a traditionally structured history, this work is styled as a ‘history of the present’ that specifies the role of the European Union in precipitating and attempting to overcome the financial and monetary crises, foreign policy quandaries on its Eastern periphery, an unmanageable escalation in migration rates, and the materialization of Eurosceptic, populist, and anti-establishment political actors at European and national levels. The specific arrangement of this thesis intends to fulfill its ultimate purpose of identifying the dynamic circumstances that aided the outcome of the United Kingdom referendum to leave the European Union