Generation and Analysis of Content for Physics-Based Video Games

The development of artificial intelligence (AI) techniques that can assist with the creation and analysis of digital content is a broad and challenging task for researchers. This topic has been most prevalent in the field of game AI research, where games are used as a testbed for solving more complex real-world problems. One of the major issues with prior AI-assisted content creation methods for games has been a lack of direct comparability to real-world environments, particularly those with realistic physical properties to consider. Creating content for such environments typically requires physics-based reasoning, which imposes many additional complications and restrictions that must be considered. Addressing and developing methods that can deal with these physical constraints, even if they are only within simulated game environments, is an important and challenging task for AI techniques that intend to be used in real-world situations. The research presented in this thesis describes several approaches to creating and analysing levels for the physics-based puzzle game Angry Birds, which features a realistic 2D environment. This research was multidisciplinary in nature and covers a wide variety of different AI fields, leading to this thesis being presented as a compilation of published work. The central part of this thesis consists of procedurally generating levels for physics-based games similar to those in Angry Birds. This predominantly involves creating and placing stable structures made up of many smaller blocks, as well as other level elements. Multiple approaches are presented, including both fully autonomous and human-AI collaborative methodologies. In addition, several analyses of Angry Birds levels were carried out using current state-of-the-art agents. A hyper-agent was developed that uses machine learning to estimate the performance of each agent in a portfolio for an unknown level, allowing it to select the one most likely to succeed. Agent performance on levels that contain deceptive or creative properties was also investigated, allowing determination of the current strengths and weaknesses of different AI techniques. The observed variability in performance across levels for different AI techniques led to the development of an adaptive level generation system, allowing for the dynamic creation of increasingly challenging levels over time based on agent performance analysis. An additional study also investigated the theoretical complexity of Angry Birds levels from a computational perspective. While this research is predominately applied to video games with physics-based simulated environments, the challenges and problems solved by the proposed methods also have significant real-world potential and applications

The Computational Complexity of Angry Birds

The physics-based simulation game Angry Birds has been heavily researched by the AI community over the past five years, and has been the subject of a popular AI competition that is currently held annually as part of a leading AI conference. Developing intelligent agents that can play this game effectively has been an incredibly complex and challenging problem for traditional AI techniques to solve, even though the game is simple enough that any human player could learn and master it within a short time. In this paper we analyse how hard the problem really is, presenting several proofs for the computational complexity of Angry Birds. By using a combination of several gadgets within this game's environment, we are able to demonstrate that the decision problem of solving general levels for different versions of Angry Birds is either NP-hard, PSPACE-hard, PSPACE-complete or EXPTIME-hard. Proof of NP-hardness is by reduction from 3-SAT, whilst proof of PSPACE-hardness is by reduction from True Quantified Boolean Formula (TQBF). Proof of EXPTIME-hardness is by reduction from G2, a known EXPTIME-complete problem similar to that used for many previous games such as Chess, Go and Checkers. To the best of our knowledge, this is the first time that a single-player game has been proven EXPTIME-hard. This is achieved by using stochastic game engine dynamics to effectively model the real world, or in our case the physics simulator, as the opponent against which we are playing. These proofs can also be extended to other physics-based games with similar mechanics.Comment: 55 Pages, 39 Figure

Culture, People and Technology: The Driving Forces for Tourism Cities Proceedings of 8th ITSA Biennial Conference 2020

This is the proceedings of the 8th Biennial Conference of the International Tourism Studies Association, held in Jakarta and Singapore, 2nd December 202

Proceedings of 8th ITSA Biennial Conference 2020

Over the past few decades, hotel guests’ service expectations grew from services such as check-in and check-out (Cobanoglu, Corbaci, Moreo & Ekinci, 2003) to expecting hotels to, amongst others, provide services relating to tourist attractions (Adler & Gordon, 2013; Yeh, Leong, Blecher & Hu, 2005). Despite these developments, South Africa (SA) is amongst the countries confronted by the minimal utilisation of tourist attractions (National Department of Tourism, 2012) and the tourists’ lack of awareness of tourist attractions within major destinations, such as Cape Town (City of Cape Town, 2013) and Durban (eThekwini Municipality, 2014). By providing tourists with services relating to tourist attractions, hotels are likely to contribute towards addressing the minimal utilisation and lack of awareness of tourist attractions. Guest orientation (Lee, 2014), self-efficacy (Jaiswal & Dhar, 2015), motivation (Hon & Leung, 2011) and effort (Marić, Marinković, Marić & Dimitrovski, 2016) are constructs that impact on the service performance of hotel staff. However, studies have not been conducted to determine the impact of these constructs on the performance of hotel staff relating to tourist attractions. This paper forms part of a PhD study in progress which explores the constructs (Guest orientation, Self-efficacy, Motivation and Effort) that impact on hotel staff’s performance of services relating to tourist attractions. The PhD adopted a qual-QUANT research method to, in phase 1, qualitatively identify emerging themes from each construct, which will be quantitatively investigated in phase 2. This paper stems from phase 1 and aims to identify via qualitative research the key themes that emerge in each of the four constructs that are associated with hotel staff’s performance of services relating to tourist attractions. Semi-structured interviews were conducted with four certified hotel concierges belonging to Les Clefs d’ Or in SA. Thematic coding was used to identify the themes emerging from the qualitative data. Eight themes emerged from Guest orientation, five from Self-efficacy, seven from Motivation and ten from Effort

From madness to eternity: Psychiatry and Sufi healing in the postmodern world

Problem: Academic study of religious healing has recognised its symbolic aspects, but has tended to frame practice as ritual, knowledge as belief. In contrast, studies of scientific psychiatry recognise that discipline as grounded in intellectual tradition and naturalistic empiricism. This asymmetry can be addressed if: (a) psychiatry is recognised as a form of “religious healing”; (b) religious healing can be shown to have an intellectual tradition which, although not naturalistic, is grounded in experience. Such an analysis may help to reveal why globalisation has meant the worldwide spread not only of modern scientific medicine, but of religious healing. An especially useful form of religious healing to contrast with scientific medicine is Sufi healing, as practised by the Naqshbandi-Haqqani order, which has become remarkable for its spread in the “West” and its adaptation to vernacular cultures. / Research questions: (1) How is knowledge generated and transmitted in the NaqshbandiHaqqani order? (2) How is healing understood and done in the Order? (3) How does the Order find a role in the modern world, and in the West in particular? / Methods: Anthropological analysis of psychiatry as religious healing; review of previous studies of Sufi healing and the Naqshbandi-Haqqani order; ethnographic participant observation in the Naqshbandi-Haqqani order, with a special focus on healing. Ethnography was done at many sites, over a period of 11 years. / Findings: (1) Knowledge is generated by means of the individual’s contact with Shaykh Nazim, who, in turn, is said to be in contact with the Prophet. Knowledge is therefore personalised, situational, and ever-changing. Purification of the nafs (psyche, soul) is held to increase the capacity for knowledge. (2) Discourse in the Naqshbandi-Haqqani order centres around healing of the soul, which is held to be a salvific and intellectual exercise. Activities and intellectual disciplines are subsumed into soul-healing. Healing techniques are eclectic and universally applied, ultimately under the perceived direction of Shaykh Nazim. (3) The Order attracts followers through charisma and personal contacts; adapts to local vernaculars; creates alternative social networks; makes everyday activities part of soul-healing; provides low-cost personalised healing; and reflects postmodern concerns and ecumenism. / Implications: Healing that reflects pre-modern, religious models of the intellect, and a medical science that is not merely naturalistic, has encompassed scientific narratives and gained adherents in the postmodern world