TY - CHAP A1 - Zhou, Neng-Fa T1 - What I have learned from all these solver competitions N2 - In this talk, I would like to share my experiences gained from participating in four CSP solver competitions and the second ASP solver competition. In particular, I’ll talk about how various programming techniques can make huge differences in solving some of the benchmark problems used in the competitions. These techniques include global constraints, table constraints, and problem-specific propagators and labeling strategies for selecting variables and values. I’ll present these techniques with experimental results from B-Prolog and other CLP(FD) systems. Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-41431 ER - TY - CHAP A1 - Schrijvers, Tom T1 - Overview of the monadic constraint programming framework N2 - A constraint programming system combines two essential components: a constraint solver and a search engine. The constraint solver reasons about satisfiability of conjunctions of constraints, and the search engine controls the search for solutions by iteratively exploring a disjunctive search tree defined by the constraint program. The Monadic Constraint Programming framework gives a monadic definition of constraint programming where the solver is defined as a monad threaded through the monadic search tree. Search and search strategies can then be defined as firstclass objects that can themselves be built or extended by composable search transformers. Search transformers give a powerful and unifying approach to viewing search in constraint programming, and the resulting constraint programming system is first class and extremely flexible. Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-41411 ER - TY - CHAP A1 - Geske, Ulrich A1 - Wolf, Armin T1 - Preface N2 - The workshops on (constraint) logic programming (WLP) are the annual meeting of the Society of Logic Programming (GLP e.V.) and bring together researchers interested in logic programming, constraint programming, and related areas like databases, artificial intelligence and operations research. In this decade, previous workshops took place in Dresden (2008), Würzburg (2007), Vienna (2006), Ulm (2005), Potsdam (2004), Dresden (2002), Kiel (2001), and Würzburg (2000). Contributions to workshops deal with all theoretical, experimental, and application aspects of constraint programming (CP) and logic programming (LP), including foundations of constraint/ logic programming. Some of the special topics are constraint solving and optimization, extensions of functional logic programming, deductive databases, data mining, nonmonotonic reasoning, , interaction of CP/LP with other formalisms like agents, XML, JAVA, program analysis, program transformation, program verification, meta programming, parallelism and concurrency, answer set programming, implementation and software techniques (e.g., types, modularity, design patterns), applications (e.g., in production, environment, education, internet), constraint/logic programming for semantic web systems and applications, reasoning on the semantic web, data modelling for the web, semistructured data, and web query languages. KW - Logic Programming KW - Constraint Solving KW - Logics KW - Deduction KW - Planing KW - Optimization Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-41401 ER - TY - CHAP A1 - Harrison, William T1 - Malleability, obliviousness and aspects for broadcast service attachment N2 - An important characteristic of Service-Oriented Architectures is that clients do not depend on the service implementation's internal assignment of methods to objects. It is perhaps the most important technical characteristic that differentiates them from more common object-oriented solutions. This characteristic makes clients and services malleable, allowing them to be rearranged at run-time as circumstances change. That improvement in malleability is impaired by requiring clients to direct service requests to particular services. Ideally, the clients are totally oblivious to the service structure, as they are to aspect structure in aspect-oriented software. Removing knowledge of a method implementation's location, whether in object or service, requires re-defining the boundary line between programming language and middleware, making clearer specification of dependence on protocols, and bringing the transaction-like concept of failure scopes into language semantics as well. This paper explores consequences and advantages of a transition from object-request brokering to service-request brokering, including the potential to improve our ability to write more parallel software. KW - service-oriented KW - aspect-oriented KW - programming language KW - middleware KW - concurrency Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-41389 ER - TY - CHAP A1 - Surajbali, Bholanathsingh A1 - Grace, Paul A1 - Coulson, Geoff T1 - Preserving dynamic reconfiguration consistency in aspect oriented middleware N2 - Aspect-oriented middleware is a promising technology for the realisation of dynamic reconfiguration in heterogeneous distributed systems. However, like other dynamic reconfiguration approaches, AO-middleware-based reconfiguration requires that the consistency of the system is maintained across reconfigurations. AO-middleware-based reconfiguration is an ongoing research topic and several consistency approaches have been proposed. However, most of these approaches tend to be targeted at specific contexts, whereas for distributed systems it is crucial to cover a wide range of operating conditions. In this paper we propose an approach that offers distributed, dynamic reconfiguration in a consistent manner, and features a flexible framework-based consistency management approach to cover a wide range of operating conditions. We evaluate our approach by investigating the configurability and transparency of our approach and also quantify the performance overheads of the associated consistency mechanisms. KW - middleware KW - reflection KW - aspects KW - dynamic reconfiguration KW - consistency Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-41379 ER - TY - CHAP A1 - Fan, Yang A1 - Masuhara, Hidehiko A1 - Aotani, Tomoyuki A1 - Nielson, Flemming A1 - Nielson, Hanne Riis T1 - AspectKE*: Security aspects with program analysis for distributed systems N2 - Enforcing security policies to distributed systems is difficult, in particular, when a system contains untrusted components. We designed AspectKE*, a distributed AOP language based on a tuple space, to tackle this issue. In AspectKE*, aspects can enforce access control policies that depend on future behavior of running processes. One of the key language features is the predicates and functions that extract results of static program analysis, which are useful for defining security aspects that have to know about future behavior of a program. AspectKE* also provides a novel variable binding mechanism for pointcuts, so that pointcuts can uniformly specify join points based on both static and dynamic information about the program. Our implementation strategy performs fundamental static analysis at load-time, so as to retain runtime overheads minimal. We implemented a compiler for AspectKE*, and demonstrate usefulness of AspectKE* through a security aspect for a distributed chat system. KW - aspect oriented programming KW - program analysis KW - security policies KW - distributed systems KW - tuple spaces Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-41369 ER - TY - CHAP A1 - Hannousse, Abdelhakim A1 - Ardourel, Gilles A1 - Douence, Rémi T1 - Views for aspectualizing component models N2 - Component based software development (CBSD) and aspectoriented software development (AOSD) are two complementary approaches. However, existing proposals for integrating aspects into component models are direct transposition of object-oriented AOSD techniques to components. In this article, we propose a new approach based on views. Our proposal introduces crosscutting components quite naturally and can be integrated into different component models. KW - aspectualization KW - VIL KW - views KW - crosscutting wrappers Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-41359 ER - TY - CHAP A1 - Bynens, Maarten A1 - Van Landuyt, Dimitri A1 - Truyen, Eddy A1 - Joosen, Wouter T1 - Towards reusable aspects: the callback mismatch problem N2 - Because software development is increasingly expensive and timeconsuming, software reuse gains importance. Aspect-oriented software development modularizes crosscutting concerns which enables their systematic reuse. Literature provides a number of AOP patterns and best practices for developing reusable aspects based on compelling examples for concerns like tracing, transactions and persistence. However, such best practices are lacking for systematically reusing invasive aspects. In this paper, we present the ‘callback mismatch problem’. This problem arises in the context of abstraction mismatch, in which the aspect is required to issue a callback to the base application. As a consequence, the composition of invasive aspects is cumbersome to implement, difficult to maintain and impossible to reuse. We motivate this problem in a real-world example, show that it persists in the current state-of-the-art, and outline the need for advanced aspectual composition mechanisms to deal with this. KW - reusable aspects KW - invasive aspects KW - aspect adapter Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-41347 ER - TY - CHAP ED - Adams, Bram ED - Haupt, Michael ED - Lohmann, Daniel T1 - Preface N2 - Aspect-oriented programming, component models, and design patterns are modern and actively evolving techniques for improving the modularization of complex software. In particular, these techniques hold great promise for the development of "systems infrastructure" software, e.g., application servers, middleware, virtual machines, compilers, operating systems, and other software that provides general services for higher-level applications. The developers of infrastructure software are faced with increasing demands from application programmers needing higher-level support for application development. Meeting these demands requires careful use of software modularization techniques, since infrastructural concerns are notoriously hard to modularize. Aspects, components, and patterns provide very different means to deal with infrastructure software, but despite their differences, they have much in common. For instance, component models try to free the developer from the need to deal directly with services like security or transactions. These are primary examples of crosscutting concerns, and modularizing such concerns are the main target of aspect-oriented languages. Similarly, design patterns like Visitor and Interceptor facilitate the clean modularization of otherwise tangled concerns. Building on the ACP4IS meetings at AOSD 2002-2009, this workshop aims to provide a highly interactive forum for researchers and developers to discuss the application of and relationships between aspects, components, and patterns within modern infrastructure software. The goal is to put aspects, components, and patterns into a common reference frame and to build connections between the software engineering and systems communities. KW - Aspektorientierte Softwareentwicklung KW - Systemsoftware KW - Middleware KW - Virtuelle Maschinen KW - Betriebssysteme KW - systems software KW - middleware KW - virtual machines KW - operating systems Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-41338 ER - TY - CHAP A1 - Palix, Nicolas A1 - Lawall, Julia L. A1 - Thomas, Gaël A1 - Muller, Gilles T1 - How Often do Experts Make Mistakes? N2 - Large open-source software projects involve developers with a wide variety of backgrounds and expertise. Such software projects furthermore include many internal APIs that developers must understand and use properly. According to the intended purpose of these APIs, they are more or less frequently used, and used by developers with more or less expertise. In this paper, we study the impact of usage patterns and developer expertise on the rate of defects occurring in the use of internal APIs. For this preliminary study, we focus on memory management APIs in the Linux kernel, as the use of these has been shown to be highly error prone in previous work. We study defect rates and developer expertise, to consider e.g., whether widely used APIs are more defect prone because they are used by less experienced developers, or whether defects in widely used APIs are more likely to be fixed. KW - History of pattern occurrences KW - bug tracking KW - Herodotos KW - Coccinelle Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-41327 ER - TY - CHAP A1 - Calvillo-Gámez, Eduardo H. A1 - Cairns, Paul T1 - Pulling the strings : a theory of puppetry for the gaming experience N2 - The paper aims to bring the experience of playing videogames closer to objective knowledge, where the experience can be assessed and falsified via an operational concept. The theory focuses on explaining the basic elements that form the core of the process of the experience. The name of puppetry is introduced after discussing the similarities in the importance of experience for both videogames and theatrical puppetry. Puppetry, then, operationalizes the gaming experience into a concept that can be assessed. Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-27509 ER - TY - CHAP A1 - Pinchbeck, Dan T1 - Trigens can’t swim : intelligence and intentionality in first person game worlds N2 - This paper explores the role of the intentional stance in games, arguing that any question of artificial intelligence has as much to do with the co-option of the player’s interpretation of actions as intelligent as any actual fixed-state systems attached to agents. It demonstrates how simply using a few simple and, in system terms, cheap tricks, existing AI can be both supported and enhanced. This includes representational characteristics, importing behavioral expectations from real life, constraining these expectations using diegetic devices, and managing social interrelationships to create the illusion of a greater intelligence than is ever actually present. It is concluded that complex artificial intelligence is often of less importance to the experience of intelligent agents in play than the creation of a space where the intentional stance can be evoked and supported. Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-27609 ER - TY - CHAP A1 - Mitsuishi, Yara T1 - Différance at play : unfolding identities through difference in videogame play N2 - This paper approaches the debate over the notion of “magic circle” through an exploratory analysis of the unfolding of identities/differences in gameplay through Derrida’s différance. Initially, différance is related to the notion of play and identity/difference in Derrida’s perspective. Next, the notion of magic circle through Derrida’s play is analyzed, emphasizing the dynamics of différance to understand gameplay as process; questioning its boundaries. Finally, the focus shifts toward the implications of the interplay of identities and differences during gameplay. Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-24697 ER - TY - CHAP A1 - Jennett, Charlene A1 - Cox, Anna L. A1 - Cairns, Paul T1 - Being "in the game" N2 - When people describe themselves as being “in the game” this is often thought to mean they have a sense of presence, i.e. they feel like they are in the virtual environment (Brown/Cairns 2004). Presence research traditionally focuses on user experiences in virtual reality systems (e.g. head mounted displays, CAVE-like systems). In contrast, the experience of gaming is very different. Gamers willingly submit to the rules of the game, learn arbitrary relationships between the controls and the screen output, and take on the persona of their game character. Also whereas presence in VR systems is immediate, presence in gaming is gradual. Due to these differences, one can question the extent to which people feel present during gaming. A qualitative study was conducted to explore what gamers actually mean when they describe themselves as being “in the game.” Thirteen gamers were interviewed and the resulting grounded theory suggests being “in the game” does not necessarily mean presence (i.e. feeling like you are the character and present in the VE). Some people use this phrase just to emphasize their high involvement in the game. These findings differ with Brown and Cairns as they suggest at the highest state of immersion not everybody experiences presence. Furthermore, the experience of presence does not appear dependent on the game being in the first person perspective or the gamer being able to empathize with the character. Future research should investigate why some people experience presence and others do not. Possible explanations include: use of language, perception of presence, personality traits, and types of immersion. Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-24682 ER - TY - CHAP A1 - Hoffstadt, Christian A1 - Nagenborg, Michael T1 - The concept of war in the World of Warcraft N2 - MMORPGs such as WORLD OF WARCRAFT can be understood as interactive representations of war. Within the frame provided by the program the players experience martial conflicts and thus a “virtual war.” The game world however requires a technical and as far as possible invisible infrastructure which has to be protected against attacks: Infrastructure means e.g. the servers on which the data of the player characters and the game’s world are saved, as well as the user accounts, which have to be protected, among other things, from “identity theft.” Besides the war on the virtual surface of the program we will therefore describe the invisible war concerning the infrastructure, the outbreak of which is always feared by the developers and operators of online-worlds, requiring them to take precautions. Furthermore we would like to focus on “virtual game worlds” as places of complete surveillance. Since action in these worlds is always associated with the production of data, total observation is theoretically possible and put into practice by the so-called “game master.” The observation of different communication channels (including user forums) serves to monitor and direct the actions on the virtual battlefield subtly, without the player feeling that his freedom is being limited. Finally, we will compare the fictional theater of war in WORLD OF WARCRAFT to the vision of “Network-Centric Warfare,” since it has often been observed that the analysis of MMORPGs is useful to the real trade of war. However, we point out what an unrealistic theater of war WORLD OF WARCRAFT really is. Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-24674 ER - TY - CHAP A1 - Schrape, Niklas T1 - Playing with information : how political games encourage the player to cross the magic circle N2 - The concept of the magic circle suggests that the experience of play is separated from reality. However, in order to interact with a game’s rule system, the player has to make meaningful interpretations of its representations – and representations are never neutral. Games with political content refer in their representations explicitly to social discourses. Cues within their representational layers provoke the player to link the experience of play to mental concepts of reality. Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-24668 ER - TY - CHAP A1 - Pohl, Kirsten T1 - Ethical reflection and emotional involvement in computer games N2 - This paper focuses on the way computer games refer to the context of their formation and ask how they might stimulate the user’s understanding of the world around him. The central question is: Do computer games have the potential to inspire our reflection about moral and ethical issues? And if so, by which means do they achieve this? Drawing on concepts of the ethical criticism in literary studies as proposed by Wayne C. Booth and Martha Nussbaum, I will argue in favor of an ethical criticism for computer games. Two aspects will be brought into focus: the ethical reflection in the artifact as a whole, and the recipient’s emotional involvement. The paper aims at evaluating the interaction of game content and game structure in order to give an adequate insight into the way computer games function and affect us. Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-24652 ER - TY - CHAP A1 - Neitzel, Britta T1 - Metacommunicative circles N2 - The paper uses Gregory Bateson’s concept of metacommunication to explore the boundaries of the ‘magic circle’ in play and computer games. It argues that the idea of a self-contained “magic circle” ignores the constant negotiations among players which establish the realm of play. The “magic circle” is no fixed ontological entity but is set up by metacommunicative play. The paper further pursues the question if metacommunication could also be found in single-player computer games, and comes to the conclusion that metacommunication is implemented in single-player games by the means of metalepsis. Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-24647 ER - TY - CHAP A1 - Mukherjee, Souvik T1 - Gameplay in the "Zone of Becoming" : locating action in the computer game N2 - Extending Alexander Galloway’s analysis of the action-image in videogames, this essay explores the concept in relation to its source: the analysis of cinema by the French philosopher Gilles Deleuze. The applicability of the concept to videogames will, therefore, be considered through a comparison between the First Person Shooter S.T.A.L.K.E.R. and Andrey Tarkovsky’s film Stalker. This analysis will compellingly explore the nature of videogame-action, its relation to player-perceptions and its location within the machinic and ludic schema. Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-24638 ER - TY - CHAP A1 - Løvlie, Anders Sundnes T1 - The rhetoric of persuasive games : freedom and discipline in America's Army N2 - This paper suggests an approach to studying the rhetoric of persuasive computer games through comparative analysis. A comparison of the military propaganda game AMERICA’S ARMY to similar shooter games reveals an emphasis on discipline and constraints in all main aspects of the games, demonstrating a preoccupation with ethos more than pathos. Generalizing from this, a model for understanding game rhetoric through balances of freedom and constraints is proposed. Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-24616 ER -