Download or read book Tracing Algorithmic Primitives in RSqueak VM written by Wassermann, Lars and published by Universitätsverlag Potsdam. This book was released on 2016-09-19 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: When realizing a programming language as VM, implementing behavior as part of the VM, as primitive, usually results in reduced execution times. But supporting and developing primitive functions requires more effort than maintaining and using code in the hosted language since debugging is harder, and the turn-around times for VM parts are higher. Furthermore, source artifacts of primitive functions are seldom reused in new implementations of the same language. And if they are reused, the existing API usually is emulated, reducing the performance gains. Because of recent results in tracing dynamic compilation, the trade-off between performance and ease of implementation, reuse, and changeability might now be decided adversely. In this work, we investigate the trade-offs when creating primitives, and in particular how large a difference remains between primitive and hosted function run times in VMs with tracing just-in-time compiler. To that end, we implemented the algorithmic primitive BitBlt three times for RSqueak/VM. RSqueak/VM is a Smalltalk VM utilizing the PyPy RPython toolchain. We compare primitive implementations in C, RPython, and Smalltalk, showing that due to the tracing just-in-time compiler, the performance gap has lessened by one magnitude to one magnitude.
Download or read book Transmorphic written by Schreiber, Robin and published by Universitätsverlag Potsdam. This book was released on 2017-03-03 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: Defining Graphical User Interfaces (GUIs) through functional abstractions can reduce the complexity that arises from mutable abstractions. Recent examples, such as Facebook's React GUI framework have shown, how modelling the view as a functional projection from the application state to a visual representation can reduce the number of interacting objects and thus help to improve the reliabiliy of the system. This however comes at the price of a more rigid, functional framework where programmers are forced to express visual entities with functional abstractions, detached from the way one intuitively thinks about the physical world. In contrast to that, the GUI Framework Morphic allows interactions in the graphical domain, such as grabbing, dragging or resizing of elements to evolve an application at runtime, providing liveness and directness in the development workflow. Modelling each visual entity through mutable abstractions however makes it difficult to ensure correctness when GUIs start to grow more complex. Furthermore, by evolving morphs at runtime through direct manipulation we diverge more and more from the symbolic description that corresponds to the morph. Given that both of these approaches have their merits and problems, is there a way to combine them in a meaningful way that preserves their respective benefits? As a solution for this problem, we propose to lift Morphic's concept of direct manipulation from the mutation of state to the transformation of source code. In particular, we will explore the design, implementation and integration of a bidirectional mapping between the graphical representation and a functional and declarative symbolic description of a graphical user interface within a self hosted development environment. We will present Transmorphic, a functional take on the Morphic GUI Framework, where the visual and structural properties of morphs are defined in a purely functional, declarative fashion. In Transmorphic, the developer is able to assemble different morphs at runtime through direct manipulation which is automatically translated into changes in the code of the application. In this way, the comprehensiveness and predictability of direct manipulation can be used in the context of a purely functional GUI, while the effects of the manipulation are reflected in a medium that is always in reach for the programmer and can even be used to incorporate the source transformations into the source files of the application.
Download or read book On the operationalization of graph queries with generalized discrimination networks written by Beyhl, Thomas and published by Universitätsverlag Potsdam. This book was released on 2017-01-12 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: Graph queries have lately gained increased interest due to application areas such as social networks, biological networks, or model queries. For the relational database case the relational algebra and generalized discrimination networks have been studied to find appropriate decompositions into subqueries and ordering of these subqueries for query evaluation or incremental updates of query results. For graph database queries however there is no formal underpinning yet that allows us to find such suitable operationalizations. Consequently, we suggest a simple operational concept for the decomposition of arbitrary complex queries into simpler subqueries and the ordering of these subqueries in form of generalized discrimination networks for graph queries inspired by the relational case. The approach employs graph transformation rules for the nodes of the network and thus we can employ the underlying theory. We further show that the proposed generalized discrimination networks have the same expressive power as nested graph conditions.
Download or read book Automatic verification of behavior preservation at the transformation level for relational model transformation written by Dyck, Johannes and published by Universitätsverlag Potsdam. This book was released on 2017-04-26 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: The correctness of model transformations is a crucial element for model-driven engineering of high quality software. In particular, behavior preservation is the most important correctness property avoiding the introduction of semantic errors during the model-driven engineering process. Behavior preservation verification techniques either show that specific properties are preserved, or more generally and complex, they show some kind of behavioral equivalence or refinement between source and target model of the transformation. Both kinds of behavior preservation verification goals have been presented with automatic tool support for the instance level, i.e. for a given source and target model specified by the model transformation. However, up until now there is no automatic verification approach available at the transformation level, i.e. for all source and target models specified by the model transformation. In this report, we extend our results presented in [27] and outline a new sophisticated approach for the automatic verification of behavior preservation captured by bisimulation resp. simulation for model transformations specified by triple graph grammars and semantic definitions given by graph transformation rules. In particular, we show that the behavior preservation problem can be reduced to invariant checking for graph transformation and that the resulting checking problem can be addressed by our own invariant checker even for a complex example where a sequence chart is transformed into communicating automata. We further discuss today's limitations of invariant checking for graph transformation and motivate further lines of future work in this direction.
Download or read book Symbolic model generation for graph properties written by Schneider, Sven and published by Universitätsverlag Potsdam. This book was released on 2017-05-09 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt: Graphs are ubiquitous in Computer Science. For this reason, in many areas, it is very important to have the means to express and reason about graph properties. In particular, we want to be able to check automatically if a given graph property is satisfiable. Actually, in most application scenarios it is desirable to be able to explore graphs satisfying the graph property if they exist or even to get a complete and compact overview of the graphs satisfying the graph property. We show that the tableau-based reasoning method for graph properties as introduced by Lambers and Orejas paves the way for a symbolic model generation algorithm for graph properties. Graph properties are formulated in a dedicated logic making use of graphs and graph morphisms, which is equivalent to firstorder logic on graphs as introduced by Courcelle. Our parallelizable algorithm gradually generates a finite set of so-called symbolic models, where each symbolic model describes a set of finite graphs (i.e., finite models) satisfying the graph property. The set of symbolic models jointly describes all finite models for the graph property (complete) and does not describe any finite graph violating the graph property (sound). Moreover, no symbolic model is already covered by another one (compact). Finally, the algorithm is able to generate from each symbolic model a minimal finite model immediately and allows for an exploration of further finite models. The algorithm is implemented in the new tool AutoGraph.
Download or read book Extending a dynamic programming language and runtime environment with access control written by Tessenow, Philipp and published by Universitätsverlag Potsdam. This book was released on 2016-11-09 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt: Complexity in software systems is a major factor driving development and maintenance costs. To master this complexity, software is divided into modules that can be developed and tested separately. In order to support this separation of modules, each module should provide a clean and concise public interface. Therefore, the ability to selectively hide functionality using access control is an important feature in a programming language intended for complex software systems. Software systems are increasingly distributed, adding not only to their inherent complexity, but also presenting security challenges. The object-capability approach addresses these challenges by defining language properties providing only minimal capabilities to objects. One programming language that is based on the object-capability approach is Newspeak, a dynamic programming language designed for modularity and security. The Newspeak specification describes access control as one of Newspeak’s properties, because it is a requirement for the object-capability approach. However, access control, as defined in the Newspeak specification, is currently not enforced in its implementation. This work introduces an access control implementation for Newspeak, enabling the security of object-capabilities and enhancing modularity. We describe our implementation of access control for Newspeak. We adapted the runtime environment, the reflective system, the compiler toolchain, and the virtual machine. Finally, we describe a migration strategy for the existing Newspeak code base, so that our access control implementation can be integrated with minimal effort.
Download or read book Improving hosted continuous integration services written by Weyand, Christopher and published by Universitätsverlag Potsdam. This book was released on 2017-02-17 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: Developing large software projects is a complicated task and can be demanding for developers. Continuous integration is common practice for reducing complexity. By integrating and testing changes often, changesets are kept small and therefore easily comprehensible. Travis CI is a service that offers continuous integration and continuous deployment in the cloud. Software projects are build, tested, and deployed using the Travis CI infrastructure without interrupting the development process. This report describes how Travis CI works, presents how time-driven, periodic building is implemented as well as how CI data visualization can be done, and proposes a way of dealing with dependency problems.
Download or read book Proceedings of the 10th Ph D Retreat of the HPI Research School on Service oriented Systems Engineering written by Meinel, Christoph and published by Universitätsverlag Potsdam. This book was released on 2018-01-17 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: Design and Implementation of service-oriented architectures imposes a huge number of research questions from the fields of software engineering, system analysis and modeling, adaptability, and application integration. Component orientation and web services are two approaches for design and realization of complex web-based system. Both approaches allow for dynamic application adaptation as well as integration of enterprise application. Commonly used technologies, such as J2EE and .NET, form de facto standards for the realization of complex distributed systems. Evolution of component systems has lead to web services and service-based architectures. This has been manifested in a multitude of industry standards and initiatives such as XML, WSDL UDDI, SOAP, etc. All these achievements lead to a new and promising paradigm in IT systems engineering which proposes to design complex software solutions as collaboration of contractually defined software services. Service-Oriented Systems Engineering represents a symbiosis of best practices in object-orientation, component-based development, distributed computing, and business process management. It provides integration of business and IT concerns. The annual Ph.D. Retreat of the Research School provides each member the opportunity to present his/her current state of their research and to give an outline of a prospective Ph.D. thesis. Due to the interdisciplinary structure of the research school, this technical report covers a wide range of topics. These include but are not limited to: Human Computer Interaction and Computer Vision as Service; Service-oriented Geovisualization Systems; Algorithm Engineering for Service-oriented Systems; Modeling and Verification of Self-adaptive Service-oriented Systems; Tools and Methods for Software Engineering in Service-oriented Systems; Security Engineering of Service-based IT Systems; Service-oriented Information Systems; Evolutionary Transition of Enterprise Applications to Service Orientation; Operating System Abstractions for Service-oriented Computing; and Services Specification, Composition, and Enactment.
Download or read book Die Cloud f r Schulen in Deutschland written by Meinel, Christoph and published by Universitätsverlag Potsdam. This book was released on 2017-03-23 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: Die digitale Entwicklung durchdringt unser Bildungssystem, doch Schulen sind auf die Veränderungen kaum vorbereitet: Überforderte Lehrer/innen, infrastrukturell schwach ausgestattete Unterrichtsräume und unzureichend gewartete Computernetzwerke sind keine Seltenheit. Veraltete Hard- und Software erschweren digitale Bildung in Schulen eher, als dass sie diese ermöglichen: Ein zukunftssicherer Ansatz ist es, die Rechner weitgehend aus den Schulen zu entfernen und Bildungsinhalte in eine Cloud zu überführen. Zeitgemäßer Unterricht benötigt moderne Technologie und eine zukunftsorientierte Infrastruktur. Eine Schul-Cloud (https://hpi.de/schul-cloud) kann dabei helfen, die digitale Transformation in Schulen zu meistern und den fächerübergreifenden Unterricht mit digitalen Inhalten zu bereichern. Den Schüler/innen und Lehrkräften kann sie viele Möglichkeiten eröffnen: einen einfachen Zugang zu neuesten, professionell gewarteten Anwendungen, die Vernetzung verschiedener Lernorte, Erleichterung von Unterrichtsvorbereitung und Differenzierung. Die Schul-Cloud bietet Flexibilität, fördert die schul- und fächerübergreifende Anwendbarkeit und schafft eine wichtige Voraussetzung für die gesellschaftliche Teilhabe und Mitgestaltung der digitalen Welt. Neben den technischen Komponenten werden im vorliegenden Bericht ausgewählte Dienste der Schul-Cloud exemplarisch beschrieben und weiterführende Schritte aufgezeigt. Das in Zusammenarbeit mit zahlreichen Expertinnen und Experten am Hasso-Plattner-Institut (HPI) entwickelte und durch das Bundesministerium für Bildung und Forschung (BMBF) geförderte Konzept einer Schul-Cloud stellt eine wichtige Grundlage für die Einführung Cloud-basierter Strukturen und -Dienste im Bildungsbereich dar. Gemeinsam mit dem nationalen Excellence-Schulnetzwerk MINT-EC als Kooperationspartner startet ab sofort die Pilotphase. Aufgrund des modularen, skalierbaren Ansatzes der Schul-Cloud kommt dem infrastrukturellen Prototypen langfristig das Potential zu, auch über die begrenzte Anzahl an Pilotschulen hinaus bundesweit effizient eingesetzt zu werden.
Download or read book Squimera written by Tim Felgentreff and published by Universitätsverlag Potsdam. This book was released on 2017 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: Software development tools that work and behave consistently across different programming languages are helpful for developers, because they do not have to familiarize themselves with new tooling whenever they decide to use a new language. Also, being able to combine multiple programming languages in a program increases reusability, as developers do not have to recreate software frameworks and libraries in the language they develop in and can reuse existing software instead. However, developers often have a broad choice with regard to tools, some of which are designed for only one specific programming language. Various Integrated Development Environments have support for multiple languages, but are usually unable to provide a consistent programming experience due to different features of language runtimes. Furthermore, common mechanisms that allow reuse of software written in other languages usually use the operating system or a network connection as the abstract layer. Tools, however, often cannot support such indirections well and are therefore less useful in debugging scenarios for example. In this report, we present a novel approach that aims to improve the programming experience with regard to working with multiple high-level programming languages. As part of this approach, we reuse the tools of a Smalltalk programming environment for other languages and build a multi-language virtual execution environment which is able to provide the same runtime capabilities for all languages. The prototype system Squimera is an implementation of our approach and demonstrates that it is possible to reuse development tools, so that they behave in the same way across all supported programming languages. In addition, it provides convenient means to reuse and even mix software libraries and frameworks written in different languages without breaking the debugging experience.
Download or read book Self Sustaining Systems written by Robert Hirschfeld and published by Springer Science & Business Media. This book was released on 2008-10-22 with total page 163 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book constitutes the refereed proceedings of the First Workshop on Self-sustaining Systems, S3, held in Potsdam, Germany, in May 2008. S3 is a forum for discussion of topics relating to computer systems and languages that are able to bootstrap, implement, modify, and maintain themselves. One property of these systems is that their implementation is based on small but powerful abstractions; examples include (amongst others) Squeak/Smalltalk, COLA, Klein/Self, PyPy/Python, Rubinius/Ruby, and Lisp. Such systems are the engines of their own replacement, giving researchers and developers great power to experiment with, and explore future directions from within their own small language kernels.
Download or read book PoC or GTFO written by Manul Laphroaig and published by No Starch Press. This book was released on 2017-10-31 with total page 792 pages. Available in PDF, EPUB and Kindle. Book excerpt: This highly anticipated print collection gathers articles published in the much-loved International Journal of Proof-of-Concept or Get The Fuck Out. PoC||GTFO follows in the tradition of Phrack and Uninformed by publishing on the subjects of offensive security research, reverse engineering, and file format internals. Until now, the journal has only been available online or printed and distributed for free at hacker conferences worldwide. Consistent with the journal's quirky, biblical style, this book comes with all the trimmings: a leatherette cover, ribbon bookmark, bible paper, and gilt-edged pages. The book features more than 80 technical essays from numerous famous hackers, authors of classics like "Reliable Code Execution on a Tamagotchi," "ELFs are Dorky, Elves are Cool," "Burning a Phone," "Forget Not the Humble Timing Attack," and "A Sermon on Hacker Privilege." Twenty-four full-color pages by Ange Albertini illustrate many of the clever tricks described in the text.
Download or read book Handbook of Computational Social Choice written by Felix Brandt and published by Cambridge University Press. This book was released on 2016-04-25 with total page 553 pages. Available in PDF, EPUB and Kindle. Book excerpt: The rapidly growing field of computational social choice, at the intersection of computer science and economics, deals with the computational aspects of collective decision making. This handbook, written by thirty-six prominent members of the computational social choice community, covers the field comprehensively. Chapters devoted to each of the field's major themes offer detailed introductions. Topics include voting theory (such as the computational complexity of winner determination and manipulation in elections), fair allocation (such as algorithms for dividing divisible and indivisible goods), coalition formation (such as matching and hedonic games), and many more. Graduate students, researchers, and professionals in computer science, economics, mathematics, political science, and philosophy will benefit from this accessible and self-contained book.
Download or read book Introduction to Computing and Programming in Python Plus My Programming Lab Access Card Package written by Mark J. Guzdial and published by Prentice Hall. This book was released on 2013-10-28 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduction to Computing and Programming in Python, 3e, uses multimedia applications to motivate introductory computer science majors or non-majors. The book's hands-on approach shows how programs can be used to build multimedia computer science applications that include sound, graphics, music, pictures, and movies. The students learn a key set of computer science tools and topics, as well as programming skills; such as how to design and use algorithms, and practical software engineering methods. The book also includes optional coverage of HCI, as well as rudimentary data structures and databases using the user-friendly Python language for implementation. Authors Guzdial and Ericson also demonstrate how to communicate compatibly through networks and do concurrent programming. 0133591522 / 9780133591521 Introduction to Computing and Programming in Python & MyProgrammingLab with eText Package Package consists of 0132923513 / 9780132923514 Introduction to Computing and Programming in Python 0133590747 / 9780133590746 MyProgrammingLab with eText -- Access Code Card -- for Introduction to Computing and Programming in Python
Download or read book Handbook of Open Source Tools written by Sandeep Koranne and published by Springer Science & Business Media. This book was released on 2010-10-17 with total page 505 pages. Available in PDF, EPUB and Kindle. Book excerpt: Handbook of Open Source Tools introduces a comprehensive collection of advanced open source tools useful in developing software applications. The book contains information on more than 200 open-source tools which include software construction utilities for compilers, virtual-machines, database, graphics, high-performance computing, OpenGL, geometry, algebra, graph theory , GUIs and more. Special highlights for software construction utilities and application libraries are included. Each tool is covered in the context of a real like application development setting. This unique handbook presents a comprehensive discussion of advanced tools, a valuable asset used by most application developers and programmers; includes a special focus on Mathematical Open Source Software not available in most Open Source Software books, and introduces several tools (eg ACL2, CLIPS, CUDA, and COIN) which are not known outside of select groups, but are very powerful. Handbook of Open Source Tools is designed for application developers and programmers working with Open Source Tools. Advanced-level students concentrating on Engineering, Mathematics and Computer Science will find this reference a valuable asset as well.
Download or read book CISA Certified Information Systems Auditor Study Guide written by David L. Cannon and published by John Wiley & Sons. This book was released on 2016-03-14 with total page 696 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ultimate CISA prep guide, with practice exams Sybex's CISA: Certified Information Systems Auditor Study Guide, Fourth Edition is the newest edition of industry-leading study guide for the Certified Information System Auditor exam, fully updated to align with the latest ISACA standards and changes in IS auditing. This new edition provides complete guidance toward all content areas, tasks, and knowledge areas of the exam and is illustrated with real-world examples. All CISA terminology has been revised to reflect the most recent interpretations, including 73 definition and nomenclature changes. Each chapter summary highlights the most important topics on which you'll be tested, and review questions help you gauge your understanding of the material. You also get access to electronic flashcards, practice exams, and the Sybex test engine for comprehensively thorough preparation. For those who audit, control, monitor, and assess enterprise IT and business systems, the CISA certification signals knowledge, skills, experience, and credibility that delivers value to a business. This study guide gives you the advantage of detailed explanations from a real-world perspective, so you can go into the exam fully prepared. Discover how much you already know by beginning with an assessment test Understand all content, knowledge, and tasks covered by the CISA exam Get more in-depths explanation and demonstrations with an all-new training video Test your knowledge with the electronic test engine, flashcards, review questions, and more The CISA certification has been a globally accepted standard of achievement among information systems audit, control, and security professionals since 1978. If you're looking to acquire one of the top IS security credentials, CISA is the comprehensive study guide you need.
Download or read book Deep Into Pharo written by Alexandre Bergel and published by Lulu.com. This book was released on 2013 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Pharo is a clean, innovative, open-source, live-programming environment. Deep into Pharo is the second volume of a series of books covering Pharo. Whereas the first volume is intended for newcomers, this second volume covers deeper topics. You will learn about Pharo frameworks and libraries such as Glamour, PetitParser, Roassal, FileSystem, Regex, and Socket. You will explore the language with chapters on exceptions, blocks, small integers, and floats. You will discover tools such as profilers, Metacello and Gofer."--Open Textbook Library.