Systematic composition of distributed objects: Processes and sessions

We consider a system with the infrastructure for the creation and interconnection of large numbers of distributed persistent objects. This system is exemplified by the Internet: potentially, every appliance and document on the Internet has both persistent state and the ability to interact with large numbers of other appliances and documents on the Internet. This paper elucidates the characteristics of such a system, and proposes the compositional requirements of its corresponding infrastructure. We explore the problems of specifying, composing, reasoning about and implementing applications in such a system. A specific concern of our research is developing the infrastructure to support structuring distributed applications by using sequential, choice and parallel composition, in the anarchic environment where application compositions may be unforeseeable and interactions may be unknown prior to actually occurring. The structuring concepts discussed are relevant to a wide range of distributed applications; our implementation is illustrated with collaborative Java processes interacting over the Internet, but the methodology provided can be applied independent of specific platforms

Programming Languages for Distributed Computing Systems

When distributed systems first appeared, they were programmed in traditional sequential languages, usually with the addition of a few library procedures for sending and receiving messages. As distributed applications became more commonplace and more sophisticated, this ad hoc approach became less satisfactory. Researchers all over the world began designing new programming languages specifically for implementing distributed applications. These languages and their history, their underlying principles, their design, and their use are the subject of this paper. We begin by giving our view of what a distributed system is, illustrating with examples to avoid confusion on this important and controversial point. We then describe the three main characteristics that distinguish distributed programming languages from traditional sequential languages, namely, how they deal with parallelism, communication, and partial failures. Finally, we discuss 15 representative distributed languages to give the flavor of each. These examples include languages based on message passing, rendezvous, remote procedure call, objects, and atomic transactions, as well as functional languages, logic languages, and distributed data structure languages. The paper concludes with a comprehensive bibliography listing over 200 papers on nearly 100 distributed programming languages

Survey and Analysis of Production Distributed Computing Infrastructures

This report has two objectives. First, we describe a set of the production distributed infrastructures currently available, so that the reader has a basic understanding of them. This includes explaining why each infrastructure was created and made available and how it has succeeded and failed. The set is not complete, but we believe it is representative. Second, we describe the infrastructures in terms of their use, which is a combination of how they were designed to be used and how users have found ways to use them. Applications are often designed and created with specific infrastructures in mind, with both an appreciation of the existing capabilities provided by those infrastructures and an anticipation of their future capabilities. Here, the infrastructures we discuss were often designed and created with specific applications in mind, or at least specific types of applications. The reader should understand how the interplay between the infrastructure providers and the users leads to such usages, which we call usage modalities. These usage modalities are really abstractions that exist between the infrastructures and the applications; they influence the infrastructures by representing the applications, and they influence the ap- plications by representing the infrastructures

An Autonomic Cross-Platform Operating Environment for On-Demand Internet Computing

The Internet has evolved into a global and ubiquitous communication medium interconnecting powerful application servers, diverse desktop computers and mobile notebooks. Along with recent developments in computer technology, such as the convergence of computing and communication devices, the way how people use computers and the Internet has changed people´s working habits and has led to new application scenarios. On the one hand, pervasive computing, ubiquitous computing and nomadic computing become more and more important since different computing devices like PDAs and notebooks may be used concurrently and alternately, e.g. while the user is on the move. On the other hand, the ubiquitous availability and pervasive interconnection of computing systems have fostered various trends towards the dynamic utilization and spontaneous collaboration of available remote computing resources, which are addressed by approaches like utility computing, grid computing, cloud computing and public computing. From a general point of view, the common objective of this development is the use of Internet applications on demand, i.e. applications that are not installed in advance by a platform administrator but are dynamically deployed and run as they are requested by the application user. The heterogeneous and unmanaged nature of the Internet represents a major challenge for the on demand use of custom Internet applications across heterogeneous hardware platforms, operating systems and network environments. Promising remedies are autonomic computing systems that are supposed to maintain themselves without particular user or application intervention. In this thesis, an Autonomic Cross-Platform Operating Environment (ACOE) is presented that supports On Demand Internet Computing (ODIC), such as dynamic application composition and ad hoc execution migration. The approach is based on an integration middleware called crossware that does not replace existing middleware but operates as a self-managing mediator between diverse application requirements and heterogeneous platform configurations. A Java implementation of the Crossware Development Kit (XDK) is presented, followed by the description of the On Demand Internet Computing System (ODIX). The feasibility of the approach is shown by the implementation of an Internet Application Workbench, an Internet Application Factory and an Internet Peer Federation. They illustrate the use of ODIX to support local, remote and distributed ODIC, respectively. Finally, the suitability of the approach is discussed with respect to the support of ODIC

DRIVER Technology Watch Report

This report is part of the Discovery Workpackage (WP4) and is the third report out of four deliverables. The objective of this report is to give an overview of the latest technical developments in the world of digital repositories, digital libraries and beyond, in order to serve as theoretical and practical input for the technical DRIVER developments, especially those focused on enhanced publications. This report consists of two main parts, one part focuses on interoperability standards for enhanced publications, the other part consists of three subchapters, which give a landscape picture of current and surfacing technologies and communities crucial to DRIVER. These three subchapters contain the GRID, CRIS and LTP communities and technologies. Every chapter contains a theoretical explanation, followed by case studies and the outcomes and opportunities for DRIVER in this field

Improving Data Access for Computational Grid Applications

High-performance computing increasingly occurs on “computational grids” composed of heterogeneous and geographically distributed systems of computers, networks, and storage devices that collectively act as a single “virtual” computer. A key challenge in this environment is to provide efficient access to data distributed across remote data servers. Our parallel I/O framework, called Armada, allows application and data-set providers to flexibly compose graphs of processing modules that describe the distribution, application interfaces, and processing required of the dataset before computation. Although the framework provides a simple programming model for the application programmer and the data-set provider, the resulting graph may contain bottlenecks that prevent efficient data access. In this paper, we present an algorithm used to restructure Armada graphs that distributes computation and data flow to improve performance in the context of a wide-area computational grid

High school students’ social media usage : an application on user behaviors, preferences and reasons based on the uses and gratifications theory

06.03.2018 tarihli ve 30352 sayılı Resmi Gazetede yayımlanan “Yükseköğretim Kanunu İle Bazı Kanun Ve Kanun Hükmünde Kararnamelerde Değişiklik Yapılması Hakkında Kanun” ile 18.06.2018 tarihli “Lisansüstü Tezlerin Elektronik Ortamda Toplanması, Düzenlenmesi ve Erişime Açılmasına İlişkin Yönerge” gereğince tam metin erişime açılmıştır.Günümüz dünyasında, insanlar ve kitle iletişim araçları arasında etkileşimli bir iletişim süreci vardır. Bireylerin birbirleriyle etkileşim içinde oldukları yeni medya teknolojileri türüne sosyal medya denir. Bu anlamda zamanlarının çoğunu sosyal medyada geçiren bireyler günlük yaşamlarının yanı sıra çevrimiçi bir yaşam da sürdürürler. Sosyal medyadan en çok zaman geçiren ve etkilenen gruplardan biri de lise öğrencileridir diyebiliriz. Bu nedenle, bu çalışma Eskişehir'deki lise öğrencilerinin sosyal medya kullanım motivasyonlarını Kullanımlar ve Doyumlar Kuramı çerçevesinde belirlemeyi amaçlamaktadır. Anket ile yapılan araştırmada, 445 kullanıcıya hazırlanan ölçek soruları soruldu. Çalışmada, nicel veri toplama tekniklerinden biri olan anket uygulanmış olup, elde edilen veriler Statistical Package for the Social Sciences (SPSS) programı ile yorumlanmıştır. Elde edilen veriler kodlama yöntemiyle çözümlenmiştir. Faktör analizi ile 5 farklı kullanım ve memnuniyet saptanmıştır. Bunlar Eğlenme ve Rahatlama Motivasyonu, Sosyal Etkileşim Motivasyonu, Gözlem ve Rehberlik Motivasyonu, Karar Verme-Bilgi Motivasyonu ve Kişisel Sunum Motivasyonu olarak sıralanabilir. Bazı kullanıcıların demografik özellikleri ve sosyal medya kullanım biçimleri, farklı kullanımlar ve memnuniyetlerle ilişkilendirilmiştir.In today's world, there is an interactive communication process between people and mass media.The type of new media technologies or courses through which individuals interact each other is called social media. In this sense, individuals who spend most of their time on social media courses have constructed an online life apart their daily lives. One of the most influenced groups by social media is high school students. Therefore, this study aims to determine the motivations of social media usage of high school students in Eskisehir within the framework of Uses and Gratifications Theory. In the research conducted with the questionnaire, 445 users prepared scale questions were asked. The questionnaire, which is one of the quantitative data collection techniques, is applied and, the obtained data is interpreted through the Statistical Package for the Social Sciences (SPSS) program. The data obtained were interpreted by coding. Factor analysis revealed 5 different uses and gratificaiton. These can be listed as Recreation and Relaxation Motivation, Social Interaction Motivation, Observation and Guidance Motivation, Decision-Making-Information Motivation and, Personal Presentation Motivation. Some user demographics and social media usage patterns have been associated with different uses and gratifications

Java Grande Forum Report: Making Java Work for High-End Computing

This document describes the Java Grande Forum and includes its initial deliverables.Theseare reports that convey a succinct set of recommendations from this forum to SunMicrosystems and other purveyors of Java™ technology that will enable GrandeApplications to be developed with the Java programming language

The complexity paradigm for studying human communication: a summary and integration of two fields

There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy. Hamlet (Act 1, Scene 5). This popular quote from Hamlet might be recast for the field of communication as “There are more things in science than are dreamt of in our philosophies”. This article will review several new and strange ideas from complexity science about how the natural world is organized and how we can go about researching it. These strange ideas, (e.g., deterministic, but unpredictable systems) resonate with many communication phenomena that our field has traditionally had difficulty studying. By reviewing these areas, we hope to add a new, compelling and useful way to think about science that goes beyond the current dominant philosophy of science employed in communication. Though the concepts reviewed here are difficult and often appear at odds with the dominant paradigm; they are not. Instead, this approach will facilitate research on problems of communication process and interaction that the dominant paradigm has struggled to study. Specifically, this article explores the question of process research in communication by reviewing three major paradigms of science and then delving more deeply into the most recent: complexity science. The article provides a broad overview of many of the major ideas in complexity science and how these ideas can be used to study many of the most difficult questions in communication science. It concludes with suggestions going forward for incorporating complexity science into communication