For decades, digital technologies have been used to offer engaging experiences in cultural heritage sites, and these experiences have shown useful as a means to convey the histories associated with the sites. While some experiences are information-driven (e.g., tour guides), others are story-driven and therefore need a narrative justification for why the past and the present collide and in which way. This paper explores how narrative conventions from genre fiction – specifically, ghost stories, science fiction, historical fiction and fantasy – can frame narrative content in cultural heritage sites. We discuss these specific literary genres and their use in locative games to achieve the temporal collisions necessary for framing story-driven locative cultural heritage experiences. We identify the nature of the main temporal connections used by the different genres (including issues of narrative control) and offered a tentative mapping of the temporal connections onto an actual cultural heritage site.

Abstract Mobile digital media technologies, such as smartphones, have great potential for in situ storytelling in cultural heritage sites. By geo-locating narrative content across a site, it can be experienced simultaneously with the physical site, creating a situated narrative of historical relevance. However, looking at and interacting with mobile devices tend to capture the user’s attention and all too easily distract from the site. For this reason, it is important to strike a balance between immersion (into the digital content) and presence (in the physical site). In this paper, we describe an approach to locative storytelling for cultural heritage, which is based on the exclusive use of sound and music for all ludonarrative aspects of the experience and based on the concept of psychogeography, i.e., how places make us feel. Our case study is the Battle of the Boyne in Ireland, the site of the eponymous battle that took place on 1 July 1690 (O. S.) between the forces of the deposed King James II and those of King William III. The battle is considered one of the most significant events in Irish and English history and is part of a wider struggle for power across 17th century Europe. We present our narrative design, sound and music design, game design, which together are captured in our ludonarrative engine in which a combination of historical narrative, music narrative and spatial audio navigation are closely intertwined with game mechanics, creating an immersive experience for cultural, educational and intergenerational engagement.

Data structures and algorithms are core topics in Computer Science, and they are essential for the development of efficient software. However, data structures and algorithmic concepts are abstract and difficult to relate to previous knowledge. From a constructivist point of view, it is important that new experiences and information link to previous knowledge in order to create new knowledge. This paper presents work-in-progress on the development and evaluation of a serious game for teaching Binary Search Trees (BST) called DS-Hacker (Data Structure Hacker). DS-Hacker aims to introduce BST concepts to college students by means of relating well-known game elements with BST concepts.

Procedural content generation (PCG) for games has existed since the 1980s and is becoming increasingly important for creating game worlds, backstory, and characters across many genres, in particular, open-world games, such as Minecraft (2011) and No Man's Sky (2016). A particular challenge faced by such games is that the content and/or gameplay may become repetitive. Puzzles constitute an effective technique for improving gameplay by offering players interesting problems to solve, but the use of PCG for generating puzzles has been limited compared with its use for other game elements, and efforts have focused mainly on games that are strictly puzzle games, rather than creating puzzles to be incorporated into other genres. Nevertheless, a significant body of work exists, which allows puzzles of different types to be generated algorithmically, and there is scope for much more research into this area. This paper presents a detailed survey of existing work in PCG for puzzles, reviewing 32 methods within 11 categories of puzzles. For the purpose of analysis, this paper identifies a total of seven salient characteristics related to the methods, which are used to show commonalities and differences between techniques and to chart promising areas for future research.

Service-oriented computing is becoming an increasingly popular paradigm for modelling and building distributed systems in open and heterogeneous environments. However, proposed service-oriented architectures are typically based on centralised components, such as service registries or service brokers, that introduce reliability, management, and performance issues. This paper describes an approach to fully decentralise a service-oriented architecture using a self-organising peer-to-peer network maintained by service providers and consumers. The design is based on a gradient peer-to-peer topology, which allows the system to replicate a service registry using a limited number of the most stable and best performing peers. The paper evaluates the proposed approach through extensive simulation experiments and shows that the decentralised registry and the underlying peer-to-peer infrastructure scale to a large number of peers and can successfully manage high peer churn rates.

Earth tremors are a constant, intrinsic part of our planet's nature and a visceral experience when first encountered.

Message delivery in sparse mobile ad hoc networks (MANETs) is difficult due to the fact that the network graph is rarely (if ever) connected. A key challenge is to find a route that can provide good delivery performance and low end-to-end delay in a disconnected network graph where nodes may move freely. We cast this challenge as an information flow problem in a social network. This paper presents social network analysis metrics that may be used to support a novel and practical forwarding solution to provide efficient message delivery in disconnected delay-tolerant MANETs. These metrics are based on social analysis of a node's past interactions and consists of three locally evaluated components: a node's "betweenness" centrality (calculated using ego networks) and a node's social 'similarity' to the destination node and a node's tie strength relationship with the destination node. We present simulations using three real trace data sets to demonstrate that by combining these metrics delivery performance may be achieved close to epidemic routing but with significantly reduced overhead. Additionally, we show improved performance when compared to PRoPHET routing.

Clustering involves arranging a P2P overlay network's topology so that peers having certain characteristics are grouped together as neighbors. Clustering can be used to organize a P2P overlay network so that requests are routed more efficiently. The peers lack of a global awareness of the overlay network's topology in a P2P network makes it difficult to develop algorithms for clustering peers. This paper presents two decentralized algorithms for clustering peers. The algorithms are concrete realizations of of an algorithm called the abstract Schelling's algorithm (based on a model from sociology by Thomas Schelling) that can be used to create a family of self-* topology adaptation algorithms for P2P overlay networks. The proposed clustering algorithms are easy to implement, are not designed for clustering on a specific criteria and do not require separate algorithms to handle the flux of peers on the overlay network. The paper presents simulation results for applying the algorithm on random small-world topologies.

Message delivery in sparse Mobile Ad hoc Networks (MANETs) is difficult due to the fact that the network graph is rarely (if ever) connected. A key challenge is to find a route that can provide good delivery performance and low end-to-end delay in a disconnected network graph where nodes may move freely. This paper presents a multidisciplinary solution based on the consideration of the so-called small world dynamics which have been proposed for economy and social studies and have recently revealed to be a successful approach to be exploited for characterising information propagation in wireless networks. To this purpose, some bridge nodes are identified based on their centrality characteristics, i.e., on their capability to broker information exchange among otherwise disconnected nodes. Due to the complexity of the centrality metrics in populated networks the concept of ego networks is exploited where nodes are not required to exchange information about the entire network topology, but only locally available information is considered. Then SimBet Routing is proposed which exploits the exchange of pre-estimated "betweenness' centrality metrics and locally determined social "similarity' to the destination node. We present simulations using real trace data to demonstrate that SimBet Routing results in delivery performance close to Epidemic Routing but with significantly reduced overhead. Additionally, we show that SimBet Routing outperforms PRoPHET Routing, particularly when the sending and receiving nodes have low connectivity.

Searching and organization of peers are fundamental challenges in P2P networks. Unstructured networks, such as Gnutella, inefficiently use broadcast searches and random neighbors. Structured networks are similarly inefficient, as they generally rely on globally unique identifiers (GUIDs) which are assigned irrespective of content, which prevents fuzzy semantic searches. In both types of network search, neighbors establish trust between themselves, regardless of whether or not their content is likely to satisfy searches. We present the idea of using context-based profiles to describe peers. This enables self-organizing clusters of similar peers. A profile represents a peer's expertise based on content and responsiveness. By refining the search process using these profiles, more efficient directed searches are possible. Moreover, expertise provides a basis for trust establishment.

CORBA, the Common Object Request Broker Architecture, defines a framework for developing object-oriented distributed applications.Unfortunately, current implementations of CORBA have not been designed with support for mobile computers in mind.Using CORBA in a mobile environment raises a number of problems due to hardware mobility and the characteristics of wireless networks.This paper identifies and discusses these problems and presents the design and implementation of our Architecture for Location Independent CORBA Environments (ALICE).ALICE allows CORBA objects running on mobile devices to interact transparently with objects hosted by off-the-shelf CORBA implementations.Importantly, ALICE allows server as well as client objects to reside on mobile hosts without relying on a centralised location register to keep track of their whereabouts.1 introduction CORBA, the Common Object Request Broker Architecture [7], from the Object Management Group (OMG), defines a framework for developing object-oriented distributed applications.CORBA is based on the clientserver paradigm and the most important component in the architecture is the Object Request Broker (ORB) which is responsible for relaying object invocations from clients to server objects.Initially, the CORBA standard made no provision for interoperability between ORBS supplied by different vendors.Later versions of the standard addressed this issue by defining a standard protocol for inter-ORB communication which is known as the General Inter-ORB Protocol (GIOP) [7, Chapter 131 and which can PeMkion to make digital or hard copies of all or part of this work t'or PCrSOnal Or ChirOOnl use is granted without fee provided that comicare not made or distributed for profit or commercial advarltage and that copies bear this notice and the f'ull citation on the first page.ho copy otheRvise, to republish, to post on servers or to redistribute to lists.rcquircs prior specific permission and/or a fee.