Coping with uncertainty in a location-based game

With location-based games, how you manage uncertainty can make the difference between fun and fiasco. Game designers should know what uncertainties to hide and what to reveal to create an engaging experience. This article describes our experiences, focusing on uncertainty, in publicly deploying an experimental, mobile mixed-reality game called Can You See Me Now?.     

The differences in motivations of online game players and offline game players: A combined analysis of three studies at higher education level

Computer games have become a highly popular form of entertainment and have had a large impact on how University students spend their leisure time. Due to their highly motivating properties computer games have come to the attention of educationalists who wish to exploit these highly desirable properties for educational purposes. Several studies have been performed looking at motivations for playing computer games in a general context and in a Higher Education (HE) context. These studies did not focus on the differences in motivations between online and offline game players. Equally the studies did not look at the differences in motivations of people who prefer single player games and people who prefer multiplayer games. If games-based learning is to become a recognised teaching approach then such motivations for playing computer games must be better understood. This paper presents the combined analysis of three studies at HE level, performed over a four year period from 2005 to 2009. The paper focuses on differences of motivations in relation to single player/multiplayer preference and online/offline game participation. The study found that challenge is the top ranking motivation and recognition is the lowest ranking motivation for playing computer games in general. Challenge is also the top ranking motivation for playing games in HE while fantasy and recognition are the lowest ranking motivations for playing games in HE. Multiplayer gamers derive more competition, cooperation, recognition, fantasy and curiosity from playing games and online gamers derive more challenge, cooperation, recognition and control from playing games. Multiplayer gamers and online gamers ranked competition, cooperation and recognition significantly more important for playing games in HE than single players and offline participants.     

RTS游戏中用户行为的神经网络预测模型

即时战略游戏(简称RTS游戏)中,用户的行为由于游戏自身庞大的决策空间而难以预测.针对这个问题,提出了通过对RTS游戏的对战记录进行分析,建立5种结构的神经网络模型来预测用户行为的方法.模型考虑了不同时间片的状态对于决策行为的影响,设计了单时间片输入和双时间片输入的神经网络,并与基于动态贝叶斯网络的模型进行了比较.实验结果表明,基于单时间片输入的神经网络模型能够更加快速地完成训练过程并达到满意的预测准确度.     

Analytical solution for a class of linear quadratic open-loop Nash game with multiple players

In this paper, the Nash equilibria for differential games with multiple players is studied. A method for solving the Riccati-type matrix differential equations for open-loop Nash strategy in linear quadratic game with multiple players is presented and analytical solution is given for a type of differential games in which the system matrix can be diagonalizable. As the special cases, the Nash equilibria for some type of differential games with particular structure is studied also, and some results in previous literatures are extended. Finally, a numerical example is given to illustrate the effectiveness of the solution procedure.     

On the solution of hierarchical game under uncertainty with total risk of players

In the paper a static two-level hierarchical game under uncertainty conditions is investigated. The guaranteed Nash equilibrium is constructed between players of levels, which is based on the total risk function. It is shown, that the proposed equilibrium for this game is partially interchangeable with another equilibrium situation and cannot be improved. Properties of the risk function are revealed. The algorithm of solving the game is given and an example is considered.     

Design and development of a location-based mobile learning system to facilitate English learning

Rapid technological developments along with the popularity of the Internet and mobile devices in recent years have allowed learners to undertake learning outside the confines of the physical classroom and immerse themselves in actual locations and situations. This has led to a proliferation of research in this field together with the design and development that integrate the use of mobile devices, allowing students to undertake mobile context-aware learning. In this study, 64 Taiwanese tertiary students evaluated a learning system about plants in the English language. This location-based mobile learning system to facilitate English learning was based on mobile context-aware learning and related theories. The analysis, design, development, implementation, and evaluation model was used for the system development. Analysis of users’ requirements indicated that the majority of subjects preferred teaching materials with text and images presented on web pages on mobile devices, and that the user interface should be simple. Feedback from the evaluation of the system included suggestions to improve the maps, words, and images provided, as well as the sensing range of the global positioning system. In addition, providing forum feedback and an audio guide may be strategies to enhance users’ experience of using the system. After modifications, the final product was a fully functional system for learning about plants in English. Mobile learning is the future developmental trend in the field of education. It is anticipated that the design and development of the proposed system will serve as a reference for other researchers and future developments in mobile learning systems.     

Interweaving place and story in a location-based audio drama

This paper presents a qualitative study of an interactive audio drama facilitated by a location-based application. The investigation focuses on an accessible experience, a play in which the audience members simply trigger new scenes of the audio drama as they walk to predefined city areas. The findings draw attention to the role of the mobile technology in facilitating this particular artistic experience. Furthermore, they illustrate the various levels at which creative imagination and open interpretation emerge as audience members seek to make sense of the interrelations between the locative media experienced and elements of the places inhabited during the audio narrative. In concluding the article, designing for loose coupling between mobile media and physical places is suggested as a strategy to enable people’s engagement in meaningful experience through the use of various location-based services.     

From location to location pattern privacy in location-based services

Location privacy is extensively studied in the context of location-based services (LBSs). Typically, users are assigned a location privacy profile and the precise locations are cloaked so that the privacy profile is not compromised. Though being well-defined for snapshot location privacy, these solutions require additional precautions and patches in case of consecutive LBS requests on the user trajectory. The attacker can exploit some background knowledge like maximum velocity to compromise the privacy profile. To protect against this kind of location privacy attacks, PROBE (Damiani et al. in Trans Data Priv 3(2):123–148, 2010)-like systems constantly check location privacy violations and alter requests as necessary. Clearly, the location privacy is defined in terms of snapshot locations. Observing that there are usually user-specific movement patterns existing in the shared LBS requests, this work extends location privacy to location pattern privacy. We present a framework where user-specific sensitive movement patterns are defined and sanitized in offline and online fashions, respectively. Our solution uses an efficient dynamic programming approach to decide on and to prevent sensitive pattern disclosure. An extensive experimental evaluation has been carried out too.     

Evaluating a location-based application: a hybrid test and simulation environment

Complex and expensive testing and evaluation can inhibit cost-effective development of ubiquitous computing applications. A new environment for testing and evaluating system- and network-related issues in location-based applications strives to evaluate these applications prior to deployment. We discuss a health-monitoring application and its simulation environment.     

Using a computer game to develop advanced AI

Building software agents that can survive in the harsh environment of a popular computer game (Quake II) provides fresh insight into the study of artificial intelligence (AI). Our Quakebot uses Soar-an engine for making and executing decisions-as its underlying AI engine for controlling a single player. We chose Soar as our AI engine because our real research goal is to understand and develop general integrated intelligent agents     

On a game approach to optimal structural design

A game problem of structural design is formulated as a problem of playing against external circumstances. The compliance plays the role of the pay-off function. Two players — the designer and nature — try to respectively minimize or maximize it, possessing limited resources. Discrete and continual optimization problems are considered.It is proved that the essential game characteristic, the upper game value, is expressed in terms of the minimal eigenvalue of the inverse operator of the system (continual case), or the response matrix (discrete case). For a special case of convex game, this eigenvalue is equal to the value of the game, and the optimal strategies of the designer and nature are uniquely determined.     

Learning to win in a first-person shooter game

Designing a character’s behavior in a first-person shooter (FPS) game typically requires a considerable amount of effort due to a complex in-game environment. This paper proposes an efficient strategy of training a character in the Quake III Arena, a FPS game, to be more adaptive and also to have human-like learning capabilities and behaviors. Specifically, a particle swarm optimization (PSO) algorithm is introduced to provide a character with self-learning abilities. Like many computer games, the Quake III Arena utilizes a rule-based system which is constrained by several weights in the software. The effectiveness of these constrained weights is dependent upon the programmer’s knowledge about the game. In order to increase a character’s learning ability, an efficient method using the PSO algorithm is developed to determine the constrained weights for the behavior control. In the conducted experiments, the PSO algorithm is implemented to design a non-player character which is shown to be superior to the other characters originally created in the Quake III game. This efficient training strategy decreases the amount of effort required by game designers to design an intelligent character’s behavior.     

Fuzzy approaches to the game of Chicken

Game theory deals with decision-making processes involving two or more parties, also known as players, with partly or completely conflicting interests. Decision-makers in a conflict must often make their decisions under risk and under unclear or fuzzy information. In this paper, two distinct fuzzy approaches are employed to investigate an extensively studied 2×2 game model-the game of Chicken. The first approach uses a fuzzy multicriteria decision analysis method to obtain optimal strategies for the players. It incorporates subjective factors into the decision-makers' objectives and aggregates objectives using a weight vector. The second approach applies the theory of fuzzy moves (TFM) to the game of Chicken. The theory of moves (TOM) is designed to bring a dynamic dimension to the classical theory of games by allowing decision-makers to look ahead for one or several steps so that they can make a better decision. TOM is the crisp counterpart of TFM, the approach we implement here to deal with games that include fuzzy and uncertain information. The application of fuzzy approaches to the game of Chicken demonstrates their effectiveness in manipulating subjective, uncertain, and fuzzy information and provides valuable insights into the strategic aspects of Chicken     

In-store shopping with location-based retail apps: perceived value,consumer response,and the moderating effect of flow

Bricks-and-mortar retailers have recently begun to utilize mobile applications delivering location-based services (LBS) as part of their omni-channel strategy to provide consumers with new in-store experiences. In light of this trend, this study examined how consumers’ value perception influences their intention to use LBS in the store and their behavioral responses as well as the moderating effect of flow on the relationships between the perceived benefits/costs and the perceived value of LBS usage. The results indicated that benefits (perceived usefulness and perceived enjoyment) and costs (perceived complexity and perceived privacy risk) were influential antecedents shaping consumers’ value perception of LBS, which in turn impacted their intention to use LBS and behavioral responses (search and purchasing using LBS). Also, we found that the negative relationship between the perceived costs and perceived value was attenuated in high flow states than in low flow states

     

Capturing a Convex Object With Three Discs

This paper addresses the problem of capturing an arbitrary convex object P in the plane with three congruent disc-shaped robots. Given two stationary robots in contact with P, we characterize the set of positions of a third robot, the so-called capture region, that prevent P from escaping to infinity via continuous rigid motion. We show that the computation of the capture region reduces to a visibility problem. We present two algorithms for solving this problem, and for computing the capture region when P is a polygon and the robots are points (zero-radius discs). The first algorithm is exact and has polynomial time complexity. The second one uses simple hidden surface removal techniques from computer graphics to output an arbitrarily accurate approximation of the capture region; it has been implemented, and examples are presented.     

Flipping the winner of a poset game

Partially-ordered set games, also called poset games, are a class of two-player combinatorial games. The playing field consists of a set of elements, some of which are greater than other elements. Two players take turns removing an element and all elements greater than it, and whoever takes the last element wins. Examples of poset games include Nim and Chomp. We investigate the complexity of computing which player of a poset game has a winning strategy. We give an inductive procedure that modifies poset games to change the nim-value which informally captures the winning strategies in the game. For a generic poset game G, we describe an efficient method for constructing a game ¬G such that the first player has a winning strategy if and only if the second player has a winning strategy on G. This solves the long-standing problem of whether this construction can be done efficiently. This construction also allows us to reduce the class of Boolean formulas to poset games, establishing a lower bound on the complexity of poset games.     

Capturing association among items in a database

Measuring association among variables is an important step for finding solutions to many data mining problems. An existing metric might not be effective to serve as a measure of association among a set of items in a database. In this paper, we propose two measures of association, A₁ and A₂. We introduce the notion of associative itemset in a database. We express the proposed measures in terms of supports of itemsets. In addition, we provide theoretical foundations of our work. We present experimental results on both real and synthetic databases to show the effectiveness of A₂.     

Capturing the benefits of requirements engineering

Requirements management has a critical effect on an organization's development costs and software quality. The authors have developed a method that allows incremental, systematic improvement of requirements engineering and builds on existing SPI models and standards, filling in the gaps to improve schedules, budgets, and product quality