WorldWideScience

Sample records for positional differential games

  1. Differential games

    CERN Document Server

    Friedman, Avner

    2006-01-01

    This volume lays the mathematical foundations for the theory of differential games, developing a rigorous mathematical framework with existence theorems. It begins with a precise definition of a differential game and advances to considerations of games of fixed duration, games of pursuit and evasion, the computation of saddle points, games of survival, and games with restricted phase coordinates. Final chapters cover selected topics (including capturability and games with delayed information) and N-person games.Geared toward graduate students, Differential Games will be of particular interest

  2. Positional games

    CERN Document Server

    Hefetz, Dan; Stojaković, Miloš; Szabó, Tibor

    2014-01-01

    This text serves as a thorough introduction to the rapidly developing field of positional games. This area constitutes an important branch of combinatorics, whose aim it is to systematically develop an extensive mathematical basis for a variety of two-player perfect information games. These range from such popular games as Tic-Tac-Toe and Hex to purely abstract games played on graphs and hypergraphs. The subject of positional games is strongly related to several other branches of combinatorics such as Ramsey theory, extremal graph and set theory, and the probabilistic method. These notes cover a variety of topics in positional games, including both classical results and recent important developments. They are presented in an accessible way and are accompanied by exercises of varying difficulty, helping the reader to better understand the theory. The text will benefit both researchers and graduate students in combinatorics and adjacent fields.

  3. Differentially Positioned Language Games: Ethnomathematics from a Philosophical Perspective

    Science.gov (United States)

    Knijnik, Gelsa

    2012-01-01

    This paper discusses a new philosophical perspective for ethnomathematics which articulates Ludwig Wittgenstein's and Michel Foucault's theoretical notions. It is conceived as a theoretical toolbox which allows the analysis of, on the one hand, the mathematical language games of different forms of life and their family resemblances and, on the…

  4. Measurable Strategies in Differential Games

    Science.gov (United States)

    Ivanov, R. P.

    1990-02-01

    Nonlinear approach-evasion differential games are considered in which the initial data depend on the time. These games are investigated in the class of strategies that are functions of three variables, namely, the time, the phase variable, and the current value of the other player's control, and are measurable jointly with respect to the time and the phase variable. The ideas of the Pontryagin methods in differential games and Krasovskiĭ's ideas on extremal aiming are developed, and it is shown that measurable strategies have broad applicability. It is proved that measurable strategies are compatible with differential equations with discontinuous right-hand side, and general theorems on the existence of solving measurable strategies in approach-evasion problems are proved, along with some auxiliary assertions. It is shown that the saddle point condition in the small game ensures the existence of solving measurable strategies. An example is given. Bibliography: 14 titles.

  5. Dynamic optimization and differential games

    CERN Document Server

    Friesz, Terry L

    2010-01-01

    Dynamic Optimization and Differential Games has been written to address the increasing number of Operations Research and Management Science problems that involve the explicit consideration of time and of gaming among multiple agents. With end-of-chapter exercises throughout, it is a book that can be used both as a reference and as a textbook. It will be useful as a guide to engineers, operations researchers, applied mathematicians and social scientists whose work involves both the theoretical and computational aspects of dynamic optimization and differential games. Included throughout the text are detailed explanations of several original dynamic and game-theoretic mathematical models which are of particular relevance in today's technologically-driven-global economy: revenue management, oligopoly pricing, production planning, supply chain management, dynamic traffic assignment and dynamic congestion pricing. The book emphasizes deterministic theory, computational tools and applications associated with the stu...

  6. Pursuit-evasion differential games

    CERN Document Server

    Yavin, Y

    1987-01-01

    Twenty papers are devoted to the treatment of a wide spectrum of problems in the theory and applications of dynamic games with the emphasis on pursuit-evasion differential games. The problem of capturability is thoroughly investigated, also the problem of noise-corrupted (state) measurements. Attention is given to aerial combat problems and their attendant modelling issues, such as variable speed of the combatants, the three-dimensionality of physical space, and the combat problem, i.e. problems related to 'role determination'.

  7. Differential games in economic systems with delays

    Science.gov (United States)

    Kim, A. V.; Kormyshev, V. M.; Novikov, M. Yu.; Nikonov, M. A.

    2017-11-01

    In the paper, we consider application of i-smooth analysis (A.V. Kim, 2015) to differential games with delays in economics (Dockner E.J., et all, 2000; R. Isaacs, 1999). The approach is developed in the framework of the theory of positional differential games (N.N. Krasovskii, A.I. Subbotin, 1988; A.V. Kryazhimskii, Yu.S. Osipov, 1973; Yu.S. Osipov, J. Appl. Math. Mech. Vol. 35, № 1, № 6, 1971) and is based on application of the extremal shift strategy. We consider basic notions and constructions of the approach-evasion problem for linear systems with delays. The necessary and sufficient conditions of solvability the approach-evasion problem in terms of special u-stable sets are presented in another paper.

  8. The development of a differential game related to terrorism: Min-Max differential game

    Directory of Open Access Journals (Sweden)

    Abd El-Monem A. Megahed

    2017-07-01

    Full Text Available In this work, we study a differential game related to terrorism: Min-Max differential game taking into account the governmental activities such as the education quality, increasing the chances of labor, social justice, religious awareness and security arrangements. A Min-Max differential game between government and terrorist organizations is considered in this study. To obtain the optimal strategy of solving this problem, we study the analytic form of a Min-Max differential game and the governmental activities. Furthermore, a saddle point of a Min-Max differential game is studied.

  9. Do Video Games Promote Positive Youth Development?

    Science.gov (United States)

    Adachi, Paul J. C.; Willoughby, Teena

    2013-01-01

    We argue that video game play may meet Larson's (2000) criteria for fostering initiative in youth, and thus, may be related to positive outcomes such as flow, cooperation, problem solving, and reduced in-group bias. However, developmental and social psychologists examining adolescent video game use have focused heavily on how video games are…

  10. Infinite Dimensional Differential Games with Hybrid Controls

    Indian Academy of Sciences (India)

    ... zero-sum infinite dimensional differential game of infinite duration with discounted payoff involving hybrid controls is studied. The minimizing player is allowed to take continuous, switching and impulse controls whereas the maximizing player is allowed to take continuous and switching controls. By taking strategies in the ...

  11. Infinite dimensional differential games with hybrid controls

    Indian Academy of Sciences (India)

    The study of differential games with Elliott–Kalton strategies in the viscosity solution ... studied by Yong [6, 7]. ... Section 3 is devoted to the proof of the main uniqueness result for SQVI and the existence ...... Moreover, we have given explicit formulation of dynamic programming ... Financial support from NBHM is gratefully.

  12. Constrained core solutions for totally positive games with ordered players

    NARCIS (Netherlands)

    van den Brink, J.R.; van der Laan, G.; Vasil'ev, V.

    2014-01-01

    In many applications of cooperative game theory to economic allocation problems, such as river-, polluted river- and sequencing games, the game is totally positive (i.e., all dividends are nonnegative), and there is some ordering on the set of the players. A totally positive game has a nonempty

  13. A UNIFYING DIFFERENTIAL GAME OF ADVERTISING AND PROMOTIONS

    OpenAIRE

    HASSAN BENCHEKROUN

    2007-01-01

    The literature on advertising and promotions can be divided in two categories. A first group of models assume that promotion contributes (positively) to the goodwill towards the product, and a second group assumes that promotions reduce that goodwill. In this paper we build a differential game model where the impact of promotion on goodwill is endogenously determined. We conduct a comparative dynamics exercise. An unexpected result is that an increase in the sensitivity of sales to goodwill c...

  14. Local Positioning Systems in (Game) Sports

    Science.gov (United States)

    Leser, Roland; Baca, Arnold; Ogris, Georg

    2011-01-01

    Position data of players and athletes are widely used in sports performance analysis for measuring the amounts of physical activities as well as for tactical assessments in game sports. However, positioning sensing systems are applied in sports as tools to gain objective information of sports behavior rather than as components of intelligent spaces (IS). The paper outlines the idea of IS for the sports context with special focus to game sports and how intelligent sports feedback systems can benefit from IS. Henceforth, the most common location sensing techniques used in sports and their practical application are reviewed, as location is among the most important enabling techniques for IS. Furthermore, the article exemplifies the idea of IS in sports on two applications. PMID:22163725

  15. Exploring Online Game Players' Flow Experiences and Positive Affect

    Science.gov (United States)

    Chiang, Yu-Tzu; Lin, Sunny S. J.; Cheng, Chao-Yang; Liu, Eric Zhi-Feng

    2011-01-01

    The authors conducted two studies to explore online game players' flow experiences and positive affect. Our findings indicated that online game are capable of evoking flow experiences and positive affect, and games of violent or nonviolent type may not arouse players' aggression. The players could be placed into four flow conditions: flow,…

  16. Construction of solutions in certain differential games with phase constraints

    International Nuclear Information System (INIS)

    Grigor'eva, S V; Uspenskii, A A; Ushakov, V N; Pakhotinskikh, V Yu

    2005-01-01

    A differential approach-evasion game with fixed termination time is studied. It is assumed that the phase vector of the conflict-control system is subjected to constraints that form a closed set in the position space. The ideology of stable bridges is used for solving the problem. A method of convolution is proposed, which is used in several problems for constructing explicitly the stable absorption operator defining the stable bridges. A method of approximate construction of the maximal stable bridge in this game is suggested. The relations are written down that define a system of sets approximating the maximal stable bridge, and a control procedure with a guide is described, which can be used for obtaining an approximate solution of the approach problem.

  17. Carbon dioxide abatement as a differential game

    International Nuclear Information System (INIS)

    Tahvonen, O.

    1993-01-01

    The report combines predictions on greenhouse warming, CO 2 abatement costs and adaptation costs in a differential game framework. The specified model makes it possible to solve the payoffs of the subgame perfect solution of a two state variable nonautonomous problem with N unequal countries. Abatement cost parameters are calibrated with a global energy sector model and climate parameters are based on empirical time series. Simulation suggests that the backstop technology assumption in the abatement cost model may imply drastic cuts in optimal emission levels. Compared to the Nash noncooperative equilibrium a pareto optimal agreement is found to be beneficial for developing countries but more costly for the industrial world. Given the present damage estimates, the losses due to an emission stabilizing agreement may be 400 times higher than maximum potential gains from cooperation

  18. Fixed Duration Pursuit-Evasion Differential Game with Integral Constraints

    International Nuclear Information System (INIS)

    Ibragimov G I; Kuchkarov A Sh

    2013-01-01

    We investigate a pursuit-evasion differential game of countably many pursuers and one evader. Integral constraints are imposed on control functions of the players. Duration of the game is fixed and the payoff of the game is infimum of the distances between the evader and pursuers when the game is completed. Purpose of the pursuers is to minimize the payoff and that of the evader is to maximize it. Optimal strategies of the players are constructed, and the value of the game is found. It should be noted that energy resource of any pursuer may be less than that of the evader.

  19. Product Differentiation and Positioning: Confused Concepts

    OpenAIRE

    Shaheen Borna; Joseph Chapman

    1993-01-01

    This article examines two common marketing terms: product positioning and product differentiation. Many authors use these terms interchangeably, yet most marketing texts treat product positioning and product differentiation as two seperate concepts. This article attempts to identify the underlying concepts of both product differentiation and product positioning. Product differentiation is shown to be a special case of product positioning: therefore, it is suggested that marketers may want to ...

  20. Feedback nash equilibria for linear quadratic descriptor differential games

    NARCIS (Netherlands)

    Engwerda, J.C.; Salmah, S.

    2012-01-01

    In this paper, we consider the non-cooperative linear feedback Nash quadratic differential game with an infinite planning horizon for descriptor systems of index one. The performance function is assumed to be indefinite. We derive both necessary and sufficient conditions under which this game has a

  1. Feedback Nash Equilibria for Linear Quadratic Descriptor Differential Games

    NARCIS (Netherlands)

    Engwerda, J.C.; Salmah, Y.

    2010-01-01

    In this note we consider the non-cooperative linear feedback Nash quadratic differential game with an infinite planning horizon for descriptor systems of index one. The performance function is assumed to be indefinite. We derive both necessary and sufficient conditions under which this game has a

  2. Positive Emotions Associated with "Counter-Strike" Game Playing.

    Science.gov (United States)

    Shin, Mirim; Heard, Rob; Suo, Chao; Chow, Chin Moi

    2012-10-01

    Digital game playing engages people for long periods of time. The pleasure offered by digital games may explain the players' consumption of this activity. Games may elicit both positive and negative emotions, which can be measured by encephalography (EEG). The EEG alpha asymmetry index (AI) is different in positive and negative emotions and so may be used to distinguish positive from negative emotions that occur during gaming. We hypothesized that the "Counter-Strike" (CS) game (Valve Software, Bellevue, WA) is pleasurable and demonstrable with a positive EEG AI. Twelve male participants ages 18-30 years underwent EEG recordings continuously during and postgame. EEG was also recorded pregame for control conditions of baseline (sitting on a chair staring at a blank wall), movement (moving fingers on the computer keyboard with a blank screen), sound (listening to the sound of the CS game with a blank screen), and screen (watching the CS game without playing). Self-ratings of emotional responses were completed at pre-, during, and postgame. A significant decrease in the EEG AI was observed under the screen condition compared with baseline, whereas an increase was observed postgame compared with the screen condition. The participants demonstrated a positive EEG AI following the "shoot" events (shoot opponents) and negative emotions after the "being shot" events. Subjective ratings of emotional response indicated happiness during and postgame, but anger and arousal were reported only during the game. The overall results are consistent with the hypothesis that predominantly positive emotional reactions are elicited from playing the CS game and concur with positive subjective ratings of happiness. Future studies may explore the relationship of game pleasure and obsessive game play.

  3. Pathwise Strategies for Stochastic Differential Games with an Erratum to “Stochastic Differential Games with Asymmetric Information”

    International Nuclear Information System (INIS)

    Cardaliaguet, P.; Rainer, C.

    2013-01-01

    We introduce a new notion of pathwise strategies for stochastic differential games. This allows us to give a correct meaning to some statement asserted in Cardaliaguet and Rainer (Appl. Math. Optim. 59: 1–36, 2009)

  4. Pathwise Strategies for Stochastic Differential Games with an Erratum to 'Stochastic Differential Games with Asymmetric Information'

    Energy Technology Data Exchange (ETDEWEB)

    Cardaliaguet, P., E-mail: cardaliaguet@ceremade.dauphine.fr [Universite Paris-Dauphine, Ceremade (France); Rainer, C., E-mail: Catherine.Rainer@univ-brest.fr [Universite de Bretagne Occidentale (France)

    2013-08-01

    We introduce a new notion of pathwise strategies for stochastic differential games. This allows us to give a correct meaning to some statement asserted in Cardaliaguet and Rainer (Appl. Math. Optim. 59: 1-36, 2009)

  5. Finding social optima in congestion games with positive externalities

    NARCIS (Netherlands)

    de Keijzer, B.; Schäfer, G.

    2012-01-01

    We consider a variant of congestion games where every player i expresses for each resource e and player j a positive externality, i.e., a value for being on e together with player j. Rather than adopting a game-theoretic perspective, we take an optimization point of view and consider the problem of

  6. Optional contributions have positive effects for volunteering public goods games

    Science.gov (United States)

    Song, Qi-Qing; Li, Zhen-Peng; Fu, Chang-He; Wang, Lai-Sheng

    2011-11-01

    Public goods (PG) games with the volunteering mechanism are referred to as volunteering public goods (VPG) games, in which loners are introduced to the PG games, and a loner obtains a constant payoff but not participating the game. Considering that small contributions may have positive effects to encourage more players with bounded rationality to contribute, this paper introduces optional contributions (high value or low value) to these typical VPG games-a cooperator can contribute a high or low payoff to the public pools. With the low contribution, the logit dynamics show that cooperation can be promoted in a well mixed population comparing to the typical VPG games, furthermore, as the multiplication factor is greater than a threshold, the average payoff of the population is also enhanced. In spatial VPG games, we introduce a new adjusting mechanism that is an approximation to best response. Some results in agreement with the prediction of the logit dynamics are found. These simulation results reveal that for VPG games the option of low contributions may be a better method to stimulate the growth of cooperation frequency and the average payoff of the population.

  7. Sustaining cooperation in a differential game of advertising goodwill accumulation

    DEFF Research Database (Denmark)

    Jørgensen, Steffen; Gromova, Ekaterina

    2016-01-01

    The paper suggests a differential game of advertising competition among three symmetric firms, played over an infinite horizon. The objective of the research is to see if a cooperative agreement among the firms can be sustained over time. For this purpose the paper determines the characteristic...

  8. R&D, patents and innovation: a differential game approach

    NARCIS (Netherlands)

    Wang, H.-M.

    2016-01-01

    A patent race is a technological competition among firms and the firm making a first-hand innovation takes advantages of patenting. Firms strategically invest in R&D and produce knowledge in order to innovate. Instead of growing model of R&D, I use a differential game approach to investigate firms

  9. Pareto optimality in infinite horizon linear quadratic differential games

    NARCIS (Netherlands)

    Reddy, P.V.; Engwerda, J.C.

    2013-01-01

    In this article we derive conditions for the existence of Pareto optimal solutions for linear quadratic infinite horizon cooperative differential games. First, we present a necessary and sufficient characterization for Pareto optimality which translates to solving a set of constrained optimal

  10. On Concurrent Solutions in Differential Games

    Directory of Open Access Journals (Sweden)

    Romar Correa

    2011-01-01

    Full Text Available We examine solutions in which neither player is worse off from the leadership of one in a policy maker-public game. The loop model of dynamic games is used. Outcome space is dotted with equivalence classes of solutions. The Dynamic Stochastic General Equilibrium (DSGE results and their New Keynesian variants might represent one category. The economy is the neighborhood of a market-clearing equilibrium with Pareto-optimal properties modulo frictions. Our interest lies in the ‘old’ Keynesian genus where the representative state is one of involuntary unemployment. Two information sets are relevant. In the first case, agents look to the past and the present. In the second, they are bound by the information provided in the present. The standard analysis pertains to DSGE models under full information. We show, in contrast, that in a situation of structural disequilibrium and feedback information, all parties are better off reneging on the social compact to achieve a superior class of solutions.

  11. Prosocial Personality Traits Differentially Predict Egalitarianism, Generosity, and Reciprocity in Economic Games

    Directory of Open Access Journals (Sweden)

    Kun Zhao

    2016-08-01

    Full Text Available Recent research has highlighted the role of prosocial personality traits—agreeableness and honesty-humility—in egalitarian distributions of wealth in the dictator game. Expanding on these findings, we ran two studies to examine individual differences in two other forms of prosociality—generosity and reciprocity—with respect to two major models of personality, the Big Five and the HEXACO. Participants (combined N = 560 completed a series of economic games in which allocations in the dictator game were compared with those in the generosity game, a non-constant-sum wealth distribution task where proposers with fixed payoffs selected the size of their partner’s payoff (generosity. We further examined positive and negative reciprocity by manipulating a partner’s previous move (reciprocity. Results showed clear evidence of both generosity and positive reciprocity in social preferences, with allocations to a partner greater in the generosity game than in the dictator game, and greater still when a player had been previously assisted by their partner. There was also a consistent interaction with gender, whereby men were more generous when this was costless and women were more egalitarian overall. Furthermore, these distinct forms of prosociality were differentially predicted by personality traits, in line with the core features of these traits and the theoretical distinctions between them. HEXACO honesty-humility predicted dictator, but not generosity allocations, while traits capturing tendencies towards irritability and anger predicted lower generosity, but not dictator allocations. In contrast, the politeness—but not compassion—aspect of Big Five agreeableness was uniquely and broadly associated with prosociality across all games. These findings support the discriminant validity between related prosocial constructs, and have important implications for understanding the motives and mechanisms taking place within economic games.

  12. Prosocial Personality Traits Differentially Predict Egalitarianism, Generosity, and Reciprocity in Economic Games

    Science.gov (United States)

    Zhao, Kun; Ferguson, Eamonn; Smillie, Luke D.

    2016-01-01

    Recent research has highlighted the role of prosocial personality traits—agreeableness and honesty-humility—in egalitarian distributions of wealth in the dictator game. Expanding on these findings, we ran two studies to examine individual differences in two other forms of prosociality—generosity and reciprocity—with respect to two major models of personality, the Big Five and the HEXACO. Participants (combined N = 560) completed a series of economic games in which allocations in the dictator game were compared with those in the generosity game, a non-constant-sum wealth distribution task where proposers with fixed payoffs selected the size of their partner’s payoff (“generosity”). We further examined positive and negative reciprocity by manipulating a partner’s previous move (“reciprocity”). Results showed clear evidence of both generosity and positive reciprocity in social preferences, with allocations to a partner greater in the generosity game than in the dictator game, and greater still when a player had been previously assisted by their partner. There was also a consistent interaction with gender, whereby men were more generous when this was costless and women were more egalitarian overall. Furthermore, these distinct forms of prosociality were differentially predicted by personality traits, in line with the core features of these traits and the theoretical distinctions between them. HEXACO honesty-humility predicted dictator, but not generosity allocations, while traits capturing tendencies toward irritability and anger predicted lower generosity, but not dictator allocations. In contrast, the politeness—but not compassion—aspect of Big Five agreeableness was uniquely and broadly associated with prosociality across all games. These findings support the discriminant validity between related prosocial constructs, and have important implications for understanding the motives and mechanisms taking place within economic games. PMID:27555824

  13. Prosocial Personality Traits Differentially Predict Egalitarianism, Generosity, and Reciprocity in Economic Games.

    Science.gov (United States)

    Zhao, Kun; Ferguson, Eamonn; Smillie, Luke D

    2016-01-01

    Recent research has highlighted the role of prosocial personality traits-agreeableness and honesty-humility-in egalitarian distributions of wealth in the dictator game. Expanding on these findings, we ran two studies to examine individual differences in two other forms of prosociality-generosity and reciprocity-with respect to two major models of personality, the Big Five and the HEXACO. Participants (combined N = 560) completed a series of economic games in which allocations in the dictator game were compared with those in the generosity game, a non-constant-sum wealth distribution task where proposers with fixed payoffs selected the size of their partner's payoff ("generosity"). We further examined positive and negative reciprocity by manipulating a partner's previous move ("reciprocity"). Results showed clear evidence of both generosity and positive reciprocity in social preferences, with allocations to a partner greater in the generosity game than in the dictator game, and greater still when a player had been previously assisted by their partner. There was also a consistent interaction with gender, whereby men were more generous when this was costless and women were more egalitarian overall. Furthermore, these distinct forms of prosociality were differentially predicted by personality traits, in line with the core features of these traits and the theoretical distinctions between them. HEXACO honesty-humility predicted dictator, but not generosity allocations, while traits capturing tendencies toward irritability and anger predicted lower generosity, but not dictator allocations. In contrast, the politeness-but not compassion-aspect of Big Five agreeableness was uniquely and broadly associated with prosociality across all games. These findings support the discriminant validity between related prosocial constructs, and have important implications for understanding the motives and mechanisms taking place within economic games.

  14. Identification of a effective cooperation model in the game positioning in a volleyball game

    Directory of Open Access Journals (Sweden)

    Leszek Mazur

    2017-06-01

    Full Text Available Purpose: The paper is aimed at identification of a model which shows the effective cooperation in the game positioning (exactly in receiving-passing the ball in a volleyball game. Design/methodology/approach: The original research method is used in this thesis which is called pragmatic unique case study. The research is aimed at observation USA team playing volleyball during The Olympic Games in Rio de Janeiro 2016.  Findings: There is a cooperation model in receiving and passing the ball among USA volleyball team players found, based on the observation. There are also other cooperation models used by teams.                     Research and practical limitations/implications: Based in the research I can tell that there are different models of cooperation in the game positioning in volleyball. The teams which are the most effective use different models of cooperation while playing.                     Originality/value: The paper is original and leads to think about the identification of the process of cooperation in team games. More research in this field is recommended.

  15. Differential Game for a Class of Warfare Dynamic Systems with Reinforcement Based on Lanchester Equation

    OpenAIRE

    Chen, Xiangyong; Qiu, Jianlong

    2014-01-01

    This paper concerns the optimal reinforcement game problem between two opposing forces in military conflicts. With some moderate assumptions, we employ Lanchester equation and differential game theory to develop a corresponding optimization game model. After that, we establish the optimum condition for the differential game problem and give an algorithm to obtain the optimal reinforcement strategies. Furthermore, we also discuss the convergence of the algorithm. Finally, a numerical example i...

  16. Solving simple stochastic games with few coin toss positions

    DEFF Research Database (Denmark)

    Ibsen-Jensen, Rasmus; Miltersen, Peter Bro

    2011-01-01

    Gimbert and Horn gave an algorithm for solving simple stochastic games with running time O(r! n) where n is the number of positions of the simple stochastic game and r is the number of its coin toss positions. Chatterjee et al. pointed out that a variant of strategy iteration can be implemented...... to solve this problem in time 4^r r^{O(1)} n^{O(1)}. In this paper, we show that an algorithm combining value iteration with retrograde analysis achieves a time bound of O(r 2^r (r log r + n)), thus improving both time bounds. While the algorithm is simple, the analysis leading to this time bound...

  17. Solving Simple Stochastic Games with Few Coin Toss Positions

    DEFF Research Database (Denmark)

    Ibsen-Jensen, Rasmus; Miltersen, Peter Bro

    2012-01-01

    Gimbert and Horn gave an algorithm for solving simple stochastic games with running time O(r! n) where n is the number of positions of the simple stochastic game and r is the number of its coin toss positions. Chatterjee et al. pointed out that a variant of strategy iteration can be implemented...... to solve this problem in time 4 r n O(1). In this paper, we show that an algorithm combining value iteration with retrograde analysis achieves a time bound of O(r 2 r (r logr + n)), thus improving both time bounds. We also improve the analysis of Chatterjee et al. and show that their algorithm in fact has...

  18. Behavior learning in differential games and reorientation maneuvers

    Science.gov (United States)

    Satak, Neha

    method is the Direct Approximation of Value Function (DAVF) method. In this method, unlike the CSR method, the player formulates an objective function for the opponent but does not formulates a strategy directly; rather, indirectly the player assumes that the opponent is playing optimally. Thus, a value function satisfying the HJB equation corresponding to the opponent's cost function exists. The DAVF method finds an approximate solution for the value function based on previous observations of the opponent's control. The approximate solution to the value function is then used to predict the opponent's future behavior. Game examples in which only a single player is learning its opponent's behavior are simulated. Subsequently, examples in which both players in a two-player game are learning each other's behavior are simulated. In the second part of this research, a reorientation control maneuver for a spinning spacecraft will be developed. This will aid the application of behavior learning and differential games concepts to the specific scenario involving multiple spinning spacecraft. An impulsive reorientation maneuver with coasting will be analytically designed to reorient the spin axis of the spacecraft using a single body fixed thruster. Cooperative maneuvers of multiple spacecraft optimizing fuel and relative orientation will be designed. Pareto optimality concepts will be used to arrive at mutually agreeable reorientation maneuvers for the cooperating spinning spacecraft.

  19. R&D, patents and innovation: a differential game approach

    OpenAIRE

    Wang, H.-M.

    2016-01-01

    A patent race is a technological competition among firms and the firm making a first-hand innovation takes advantages of patenting. Firms strategically invest in R&D and produce knowledge in order to innovate. Instead of growing model of R&D, I use a differential game approach to investigate firms interaction of R&D behavior in a patent race. In general, knowledge is an intangible good that gives a special feature of a patent race. Whether knowledge is substitutable to the existing knowledge ...

  20. Synthesis of robust nonlinear autopilots using differential game theory

    Science.gov (United States)

    Menon, P. K. A.

    1991-01-01

    A synthesis technique for handling unmodeled disturbances in nonlinear control law synthesis was advanced using differential game theory. Two types of modeling inaccuracies can be included in the formulation. The first is a bias-type error, while the second is the scale-factor-type error in the control variables. The disturbances were assumed to satisfy an integral inequality constraint. Additionally, it was assumed that they act in such a way as to maximize a quadratic performance index. Expressions for optimal control and worst-case disturbance were then obtained using optimal control theory.

  1. Sketch for a model of four epistemological positions toward computer game play

    DEFF Research Database (Denmark)

    Leino, Olli

    2008-01-01

    The paper attempts to sketch out four distinct epistemological positions toward the player, who is understood as derived from play and game. To map out the problem field, two equally challenged positions toward computer game play are observed, emerging from inadequate treatment of the differences...... of playing a game is seen as independent of what goes on in the player’s mind (actually, the player might not even be the true subject of the game). Similar polarities are postulated regarding a game; from an exclusive viewpoint .game. is a signifying shorthand for objects, which, when observed from...

  2. Differential Game for a Class of Warfare Dynamic Systems with Reinforcement Based on Lanchester Equation

    Directory of Open Access Journals (Sweden)

    Xiangyong Chen

    2014-01-01

    Full Text Available This paper concerns the optimal reinforcement game problem between two opposing forces in military conflicts. With some moderate assumptions, we employ Lanchester equation and differential game theory to develop a corresponding optimization game model. After that, we establish the optimum condition for the differential game problem and give an algorithm to obtain the optimal reinforcement strategies. Furthermore, we also discuss the convergence of the algorithm. Finally, a numerical example illustrates the effectiveness of the presented optimal schemes. Our proposed results provide a theoretical guide for both making warfare command decision and assessing military actions.

  3. Non-cooperative stochastic differential game theory of generalized Markov jump linear systems

    CERN Document Server

    Zhang, Cheng-ke; Zhou, Hai-ying; Bin, Ning

    2017-01-01

    This book systematically studies the stochastic non-cooperative differential game theory of generalized linear Markov jump systems and its application in the field of finance and insurance. The book is an in-depth research book of the continuous time and discrete time linear quadratic stochastic differential game, in order to establish a relatively complete framework of dynamic non-cooperative differential game theory. It uses the method of dynamic programming principle and Riccati equation, and derives it into all kinds of existence conditions and calculating method of the equilibrium strategies of dynamic non-cooperative differential game. Based on the game theory method, this book studies the corresponding robust control problem, especially the existence condition and design method of the optimal robust control strategy. The book discusses the theoretical results and its applications in the risk control, option pricing, and the optimal investment problem in the field of finance and insurance, enriching the...

  4. Necessary and Sufficient Conditions for Pareto Optimality in Infinite Horizon Cooperative Differential Games

    NARCIS (Netherlands)

    Reddy, P.V.; Engwerda, J.C.

    2011-01-01

    In this article we derive necessary and sufficient conditions for the existence of Pareto optimal solutions for infinite horizon cooperative differential games. We consider games defined by non autonomous and discounted autonomous systems. The obtained results are used to analyze the regular

  5. On the analysis of a complex differential game using artificial intelligence techniques [military systems

    NARCIS (Netherlands)

    Shinar, J.; Siegel, A.W.

    1988-01-01

    The investigation is motivated by the dynamic conflict in an air-to-air combat between two aggressive aircraft, both equipped with medium-range guided missiles. It is a two-target differential game with two independent pursuit-evasion games. A description is given of the analysis of the conflict by

  6. A SURVEY OF STACKELBERG DIFFERENTIAL GAME MODELS IN SUPPLY AND MARKETING CHANNELS

    Institute of Scientific and Technical Information of China (English)

    Xiuli HE; Ashutosh PRASAD; Suresh P. SETHI; Genaro J. GUTIERREZ

    2007-01-01

    Stackelberg differential game models have been used to study sequential decision making in noncooperative games in diverse fields. In this paper, we survey recent applications of Stackelberg differential game models to the supply chain management and marketing channels literatures. A common feature of these applications is the specification of the game structure: a decentralized channel composed of a manufacturer and independent retailers, and a sequential decision procedure with demand and supply dynamics and coordination issues. In supply chain management, Stackelberg differential games have been used to investigate inventory issues, wholesale and retail pricing strategies, and outsourcing in dynamic environments. The underlying demand typically has growth dynamics or seasonal variation. In marketing, Stackelberg differential games have been used to model cooperative advertising programs, store brand and national brand advertising strategies, shelf space allocation, and pricing and advertising decisions. The demand dynamics are usually extensions of the classical advertising capital models or sales-advertising response models. We begin by explaining the Stackelberg differential game solution methodology and then provide a description of the models and results reported in the literature.

  7. A d-person Differential Game with State Space Constraints

    International Nuclear Information System (INIS)

    Ramasubramanian, S.

    2007-01-01

    We consider a network of d companies (insurance companies, for example) operating under a treaty to diversify risk. Internal and external borrowing are allowed to avert ruin of any member of the network. The amount borrowed to prevent ruin is viewed upon as control. Repayment of these loans entails a control cost in addition to the usual costs. Each company tries to minimize its repayment liability. This leads to a d -person differential game with state space constraints. If the companies are also in possible competition a Nash equilibrium is sought. Otherwise a utopian equilibrium is more appropriate. The corresponding systems of HJB equations and boundary conditions are derived. In the case of Nash equilibrium, the Hamiltonian can be discontinuous; there are d interlinked control problems with state constraints; each value function is a constrained viscosity solution to the appropriate discontinuous HJB equation. Uniqueness does not hold in general in this case. In the case of utopian equilibrium, each value function turns out to be the unique constrained viscosity solution to the appropriate HJB equation. Connection with Skorokhod problem is briefly discussed

  8. Computation of Value Functions in Nonlinear Differential Games with State Constraints

    KAUST Repository

    Botkin, Nikolai; Hoffmann, Karl-Heinz; Mayer, Natalie; Turova, Varvara

    2013-01-01

    Finite-difference schemes for the computation of value functions of nonlinear differential games with non-terminal payoff functional and state constraints are proposed. The solution method is based on the fact that the value function is a

  9. Amount of lifetime video gaming is positively associated with entorhinal, hippocampal and occipital volume.

    Science.gov (United States)

    Kühn, S; Gallinat, J

    2014-07-01

    Playing video games is a popular leisure activity among children and adults, and may therefore potentially influence brain structure. We have previously shown a positive association between probability of gray matter (GM) volume in the ventral striatum and frequent video gaming in adolescence. Here we set out to investigate structural correlates of video gaming in adulthood, as the effects observed in adolescents may reflect only a fraction of the potential neural long-term effects seen in adults. On magnetic resonance imaging (MRI) scans of 62 male adults, we computed voxel-based morphometry to explore the correlation of GM with the lifetime amount of video gaming (termed joystick years). We found a significant positive association between GM in bilateral parahippocamal region (entorhinal cortex) and left occipital cortex/inferior parietal lobe and joystick years (Pvideo game genres played, such as logic/puzzle games and platform games contributing positively, and action-based role-playing games contributing negatively. Furthermore, joystick years were positively correlated with hippocampus volume. The association of lifetime amount of video game playing with bilateral entorhinal cortex, hippocampal and occipital GM volume could reflect adaptive neural plasticity related to navigation and visual attention.

  10. Cambodia–China Relations: A Positive-Sum Game?

    Directory of Open Access Journals (Sweden)

    Pheakdey Heng

    2012-01-01

    Full Text Available China has re-emerged to become a dominant foreign player in Cambodia. Politically, Cambodia is one of China’s oldest and closest allies. Economically, China is Cambodia’s top foreign investor, a major donor, and an increasingly important trading partner. Culturally, Chinese values are deeply embedded in many aspects of Cambodian society. However, China’s dominance is surrounded by renewed controversies. While the government warmly welcomes Chinese aid, saying that it comes with no strings attached, many experts are concerned that China is providing aid for more nefarious reasons. Critics also accuse Chinese investment and aid of having exacerbated corruption, weakened governance and harmed human rights, and of ruining Cambodia’s natural resources and environment. With such controversies, it is relevant and significant to assess the roles that China has played and continues to play in Cambodia’s socio-economic development. Using expert interviews, media analysis and an extensive literature review, this paper uniquely contributes to the existing discussion on China–Cambodia relations by closely examining the controversies of China’s investment and aid, critically analysing China’s interests in Cambodia, and asking if the relationship between the two nations is a positive-sum game.

  11. The Sensitivity of State Differential Game Vessel Traffic Model

    Directory of Open Access Journals (Sweden)

    Lisowski Józef

    2016-04-01

    Full Text Available The paper presents the application of the theory of deterministic sensitivity control systems for sensitivity analysis implemented to game control systems of moving objects, such as ships, airplanes and cars. The sensitivity of parametric model of game ship control process in collision situations have been presented. First-order and k-th order sensitivity functions of parametric model of process control are described. The structure of the game ship control system in collision situations and the mathematical model of game control process in the form of state equations, are given. Characteristics of sensitivity functions of the game ship control process model on the basis of computer simulation in Matlab/Simulink software have been presented. In the end, have been given proposals regarding the use of sensitivity analysis to practical synthesis of computer-aided system navigator in potential collision situations.

  12. Playing Games: Do Game Consoles Have a Positive Impact on Girls' Learning Outcomes and Motivation?

    Science.gov (United States)

    Kitching, Lucy; Wheeler, Steve

    2013-01-01

    Games based learning is currently a hotly debated topic in education and is a fertile field of study (Holmes, 2011; Abrams, 2009). Many schools are exploring ways in which games can be embedded into the curriculum, to enhance learning through deeper engagement and higher levels of motivation (Miller & Robertson, 2010). This paper explores the…

  13. 78 FR 22554 - Nationwide Differential Global Positioning System (NDGPS)

    Science.gov (United States)

    2013-04-16

    ... accuracy and integrity of the Global Positioning System (GPS) derived positions for surface transportation..., contact LT Luke Byrd, Coast Guard, NDGPS Program Manager, telephone 202-372-1547 or email Robert.l.byrd... The NDGPS augments GPS with an additional differential correction signal. Differential GPS (DGPS...

  14. Competition and quality in health care markets: a differential-game approach.

    Science.gov (United States)

    Brekke, Kurt R; Cellini, Roberto; Siciliani, Luigi; Straume, Odd Rune

    2010-07-01

    We investigate the effect of competition on quality in health care markets with regulated prices taking a differential game approach, in which quality is a stock variable. Using a Hotelling framework, we derive the open-loop solution (health care providers set the optimal investment plan at the initial period) and the feedback closed-loop solution (providers move investments in response to the dynamics of the states). Under the closed-loop solution competition is more intense in the sense that providers observe quality in each period and base their investment on this information. If the marginal provision cost is constant, the open-loop and closed-loop solutions coincide, and the results are similar to the ones obtained by static models. If the marginal provision cost is increasing, investment and quality are lower in the closed-loop solution (when competition is more intense). In this case, static models tend to exaggerate the positive effect of competition on quality.

  15. On Some Pursuit and Evasion Differential Game Problems for an Infinite Number of First-Order Differential Equations

    Directory of Open Access Journals (Sweden)

    Abbas Badakaya Ja'afaru

    2012-01-01

    Full Text Available We study pursuit and evasion differential game problems described by infinite number of first-order differential equations with function coefficients in Hilbert space l2. Problems involving integral, geometric, and mix constraints to the control functions of the players are considered. In each case, we give sufficient conditions for completion of pursuit and for which evasion is possible. Consequently, strategy of the pursuer and control function of the evader are constructed in an explicit form for every problem considered.

  16. Analysis of Nonlinear Duopoly Games with Product Differentiation: Stability, Global Dynamics, and Control

    Directory of Open Access Journals (Sweden)

    S. S. Askar

    2017-01-01

    Full Text Available Many researchers have used quadratic utility function to study its influences on economic games with product differentiation. Such games include Cournot, Bertrand, and a mixed-type game called Cournot-Bertrand. Within this paper, a cubic utility function that is derived from a constant elasticity of substitution production function (CES is introduced. This cubic function is more desirable than the quadratic one besides its amenability to efficiency analysis. Based on that utility a two-dimensional Cournot duopoly game with horizontal product differentiation is modeled using a discrete time scale. Two different types of games are studied in this paper. In the first game, firms are updating their output production using the traditional bounded rationality approach. In the second game, firms adopt Puu’s mechanism to update their productions. Puu’s mechanism does not require any information about the profit function; instead it needs both firms to know their production and their profits in the past time periods. In both scenarios, an explicit form for the Nash equilibrium point is obtained under certain conditions. The stability analysis of Nash point is considered. Furthermore, some numerical simulations are carried out to confirm the chaotic behavior of Nash equilibrium point. This analysis includes bifurcation, attractor, maximum Lyapunov exponent, and sensitivity to initial conditions.

  17. Simple Motion Pursuit and Evasion Differential Games with Many Pursuers on Manifolds with Euclidean Metric

    Directory of Open Access Journals (Sweden)

    Atamurat Kuchkarov

    2016-01-01

    Full Text Available We consider pursuit and evasion differential games of a group of m pursuers and one evader on manifolds with Euclidean metric. The motions of all players are simple, and maximal speeds of all players are equal. If the state of a pursuer coincides with that of the evader at some time, we say that pursuit is completed. We establish that each of the differential games (pursuit or evasion is equivalent to a differential game of m groups of countably many pursuers and one group of countably many evaders in Euclidean space. All the players in any of these groups are controlled by one controlled parameter. We find a condition under which pursuit can be completed, and if this condition is not satisfied, then evasion is possible. We construct strategies for the pursuers in pursuit game which ensure completion the game for a finite time and give a formula for this time. In the case of evasion game, we construct a strategy for the evader.

  18. Positive Outcome Expectancy Mediates the Relationship Between Peer Influence and Internet Gaming Addiction Among Adolescents in Taiwan.

    Science.gov (United States)

    Wu, Jo Yung Wei; Ko, Huei-Chen; Wong, Tsui-Yin; Wu, Li-An; Oei, Tian Po

    2016-01-01

    The present study examined the role of positive outcome expectancy in the relationship between peer/parental influence and Internet gaming addiction (IGA) among adolescents in Taiwan. Two thousand, one hundred and four junior high students completed the Chen Internet Addiction Scale for IGA, Parental Influence for IGA, peer influence for IGA, and Positive Outcome Expectancy of Internet Gaming Questionnaire. Results showed that the three types of peer influences (positive attitudes toward Internet gaming, frequency of Internet game use, and invitation to play) and positive outcome expectancy were significantly and positively correlated with IGA. Moreover, peer influence was also positively correlated with positive outcome expectancy. On the other hand, positive outcome expectancy and parental influences had a low correlation. Structural equation modeling analysis revealed that positive outcome expectancy did not mediate the relationship between either type of parental influences and IGA, and only the parent's invitation to play Internet games directly predicted IGA severity. However, peers' positive attitude or the frequency of peers' Internet game use positively predicted IGA and was fully mediated through positive outcome expectancy of Internet gaming. In addition, the frequency of peers' invitation to play Internet games directly and indirectly predicted IGA severity through a partial mediation of positive outcome expectancy of Internet gaming. The overall fit of the model was adequate and was able to explain 25.0 percent of the variance. The findings provide evidence in illuminating the role of peer influences and positive outcome expectancy of Internet gaming in the process of why adolescents may develop IGA.

  19. DIFFERENCES BETWEEN FOOTBALL PLAYERS OF DIFFERENT GAMING POSITIONS BASED ON SOME BASIC AND SPECIFIC MOTOR ABILITIES

    Directory of Open Access Journals (Sweden)

    Bogdan Tomić

    2011-09-01

    Full Text Available Based on the structure competition activities, and its character can be defined as a hypothetical model of the anthropological characteristics of football players of different gaming positions. Based on hypothetical models of different football players' position can make a division into two groups of players based on game systems that are commonly used in modern football, which is 4-4-2, and the common anthropological characteristics, structure and nature of activities carried out by during the game, so the first group consists of players with smaller volumes of engagement in the game (goalkeeper, two central defenders and two strikers and the second group 190 CRNOGORSKA SPORTSKA AKADEMIJA, „Sport Mont“ časopis br. 31,32,33. consists of players with greater scope to engage in the game (two foreign players and four defensive midfielder (midfielder . The aim is to determine the difference between players of different players' positions on the basis of some basic and specific motor abilities. The sample of 206 football players aged 18 ± 0.5 years is divided into 5 subsamples according to examinees gaming position: forwarders (45, midfield players (47, defenders (41, central defenders (44 and goalkeepers (29. The battery of 16 tests (in which the results are expressed in distance and time - metric. It can be concluded that there are differences between players of different players' positions on the team in relation to the basic and specific motor skills.

  20. Differential Effects of Learning Games on Mathematics Proficiency

    Science.gov (United States)

    Chang, Mido; Evans, Michael A.; Kim, Sunha; Norton, Anderson; Samur, Yavuz

    2015-01-01

    This study examined the effects of a learning game, [The Math App] on the mathematics proficiency of middle school students. For the study, researchers recruited 306 students, Grades 6-8, from two schools in rural southwest Virginia. Over a nine-week period, [The Math App] was deployed as an intervention for investigation. Students were assigned…

  1. Experimental study of the differential effects of playing versus watching violent video games on children's aggressive behavior.

    Science.gov (United States)

    Polman, Hanneke; de Castro, Bram Orobio; van Aken, Marcel A G

    2008-01-01

    There is great concern about the effects of playing violent video games on aggressive behavior. The present experimental study was aimed at investigating the differential effects of actively playing vs. passively watching the same violent video game on subsequent aggressive behavior. Fifty-seven children aged 10-13 either played a violent video game (active violent condition), watched the same violent video game (passive violent condition), or played a non-violent video game (active non-violent condition). Aggression was measured through peer nominations of real-life aggressive incidents during a free play session at school. After the active participation of actually playing the violent video game, boys behaved more aggressively than did the boys in the passive game condition. For girls, game condition was not related to aggression. These findings indicate that, specifically for boys, playing a violent video game should lead to more aggression than watching television violence. Copyright 2007 Wiley-Liss, Inc.

  2. Periodicity and positivity of a class of fractional differential equations.

    Science.gov (United States)

    Ibrahim, Rabha W; Ahmad, M Z; Mohammed, M Jasim

    2016-01-01

    Fractional differential equations have been discussed in this study. We utilize the Riemann-Liouville fractional calculus to implement it within the generalization of the well known class of differential equations. The Rayleigh differential equation has been generalized of fractional second order. The existence of periodic and positive outcome is established in a new method. The solution is described in a fractional periodic Sobolev space. Positivity of outcomes is considered under certain requirements. We develop and extend some recent works. An example is constructed.

  3. Signal differentiation in position tracking control of dc motors

    International Nuclear Information System (INIS)

    Beltran-Carbajal, F; Valderrabano-Gonzalez, A; Rosas-Caro, J C

    2015-01-01

    An asymptotic differentiation approach with respect to time is used for on-line estimation of velocity and acceleration signals in controlled dc motors. The attractive feature of this differentiator of signals is that it does not require any system mathematical model, which allows its use in engineering systems that require the signal differentiation for its control, identification, fault detection, among other applications. Moreover, it is shown that the differentiation approach can be applied for output signals showing a chaotic behavior. In addition a differential flatness control scheme with additional integral compensation of the output error is proposed for tracking tasks of position reference trajectories for direct current electric motors using angular position measurements only

  4. Cue-induced positive motivational implicit response in young adults with Internet gaming addiction.

    Science.gov (United States)

    Yen, Ju-Yu; Yen, Cheng-Fang; Chen, Cheng-Sheng; Tang, Tze-Chun; Huang, Tzu-Hui; Ko, Chih-Hung

    2011-12-30

    This study evaluated the positive motivational implicit response to Internet gaming cues (i.e., screenshots of popular online games) to identify potential mechanisms of dyscontrolled Internet use in young adults with Internet gaming addiction (IGA). The final analysis included 64 young adults with IGA and 71 control subjects. The subjects completed the implicit association task to test their reaction to congruent pairing (Internet gaming screenshot paired with liked words) and incongruent pairing (Internet gaming screenshot paired with disliked words). The results demonstrated that, compared to the control group, the IGA group reacted faster to congruent pairing. It suggests that the IGA group had a positive motivational implicit response to screenshots of online games. Implicit cognition is an important mechanism of dyscontrolled substance use, such as alcohol dependence. This result suggests that implicit cognition might also be associated with dyscontrolled online gaming. The findings also demonstrate the important role of implicit cognition in dyscontrolled Internet use in young adults with IGA. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Differential Effects of Music and Video Gaming During Breaks on Auditory and Visual Learning.

    Science.gov (United States)

    Liu, Shuyan; Kuschpel, Maxim S; Schad, Daniel J; Heinz, Andreas; Rapp, Michael A

    2015-11-01

    The interruption of learning processes by breaks filled with diverse activities is common in everyday life. This study investigated the effects of active computer gaming and passive relaxation (rest and music) breaks on auditory versus visual memory performance. Young adults were exposed to breaks involving (a) open eyes resting, (b) listening to music, and (c) playing a video game, immediately after memorizing auditory versus visual stimuli. To assess learning performance, words were recalled directly after the break (an 8:30 minute delay) and were recalled and recognized again after 7 days. Based on linear mixed-effects modeling, it was found that playing the Angry Birds video game during a short learning break impaired long-term retrieval in auditory learning but enhanced long-term retrieval in visual learning compared with the music and rest conditions. These differential effects of video games on visual versus auditory learning suggest specific interference of common break activities on learning.

  6. Quantification of Competitive Game Demands of NCAA Division I College Football Players Using Global Positioning Systems.

    Science.gov (United States)

    Wellman, Aaron D; Coad, Sam C; Goulet, Grant C; McLellan, Christopher P

    2016-01-01

    The aim of the present study was to examine the competitive physiological movement demands of National Collegiate Athletic Association (NCAA) Division I college football players using portable global positioning system (GPS) technology during games and to examine positional groups within offensive and defensive teams, to determine if a player's physiological requirements during games are influenced by playing position. Thirty-three NCAA Division I Football Bowl Subdivision football players were monitored using GPS receivers with integrated accelerometers (GPSports) during 12 regular season games throughout the 2014 season. Individual data sets (n = 295) from players were divided into offensive and defensive teams and subsequent position groups. Movement profile characteristics, including total, low-intensity, moderate-intensity, high-intensity, and sprint running distances (m), sprint counts, and acceleration and deceleration efforts, were assessed during games. A one-way ANOVA and post-hoc Bonferroni statistical analysis were used to determine differences in movement profiles between each position group within offensive and defensive teams. For both offensive and defensive teams, significant (p ≤ 0.05) differences exist between positional groups for game physical performance requirements. The results of the present study identified that wide receivers and defensive backs completed significantly (p ≤ 0.05) greater total distance, high-intensity running, sprint distance, and high-intensity acceleration and deceleration efforts than their respective offensive and defensive positional groups. Data from the present study provide novel quantification of position-specific physical demands of college football games and support the use of position-specific training in the preparation of NCAA Division I college football players for competition.

  7. Differential Neural Networks for Identification and Filtering in Nonlinear Dynamic Games

    Directory of Open Access Journals (Sweden)

    Emmanuel García

    2014-01-01

    Full Text Available This paper deals with the problem of identifying and filtering a class of continuous-time nonlinear dynamic games (nonlinear differential games subject to additive and undesired deterministic perturbations. Moreover, the mathematical model of this class is completely unknown with the exception of the control actions of each player, and even though the deterministic noises are known, their power (or their effect is not. Therefore, two differential neural networks are designed in order to obtain a feedback (perfect state information pattern for the mentioned class of games. In this way, the stability conditions for two state identification errors and for a filtering error are established, the upper bounds of these errors are obtained, and two new learning laws for each neural network are suggested. Finally, an illustrating example shows the applicability of this approach.

  8. Optimal Control Strategies in a Two Dimensional Differential Game Using Linear Equation under a Perturbed System

    Directory of Open Access Journals (Sweden)

    Musa Danjuma SHEHU

    2008-06-01

    Full Text Available This paper lays emphasis on formulation of two dimensional differential games via optimal control theory and consideration of control systems whose dynamics is described by a system of Ordinary Differential equation in the form of linear equation under the influence of two controls U(. and V(.. Base on this, strategies were constructed. Hence we determine the optimal strategy for a control say U(. under a perturbation generated by the second control V(. within a given manifold M.

  9. A numerical algorithm to find all feedback Nash equilibria in scalar affine quadratic differential games

    NARCIS (Netherlands)

    Engwerda, Jacob

    2015-01-01

    This note deals with solving scalar coupled algebraic Riccati equations. These equations arise in finding linear feedback Nash equilibria of the scalar N-player affine quadratic differential game. A numerical procedure is provided to compute all the stabilizing solutions. The main idea is to

  10. Analysis of a monetary union enlargement in the framework of linear-quadratic differential games

    NARCIS (Netherlands)

    Plasmans, J.E.J.; Engwerda, J.C.; van Aarle, B.; Michalak, T.

    2009-01-01

    "This paper studies the effects of a monetary union enlargement using the techniques and outcomes from an extensive research project on macroeconomic policy coordination in the EMU. Our approach is characterized by two main pillars: (i) linear-quadratic differential games to capture externalities,

  11. Sensation Seeking and Online Gaming Addiction in Adolescents: A Moderated Mediation Model of Positive Affective Associations and Impulsivity.

    Science.gov (United States)

    Hu, Jianping; Zhen, Shuangju; Yu, Chengfu; Zhang, Qiuyan; Zhang, Wei

    2017-01-01

    Based on the Dual Systems Model (Somerville et al., 2010; Steinberg, 2010a) and the biosocial-affect model (Romer and Hennessy, 2007) of adolescent sensation seeking and problem behaviors, the present study examined how (affective associations with online games as a mediator) and when (impulsivity as a moderator) did sensation seeking influence online gaming addiction in adolescence. A total of 375 Chinese male adolescents (mean age = 16.02 years, SD = 0.85) from southern China completed anonymous questionnaires regarding sensation seeking, positive affective associations with online games, impulsivity, and online gaming addiction. Our findings revealed that sensation seeking, positive affective associations with online games and impulsivity were each significantly and positively associated with online gaming addiction in adolescents. Positive affective associations mediated the relationship between sensation seeking and online gaming addiction. Further, impulsivity moderated the relationship between positive affective associations and online gaming addiction, such that the association between positive affective association and online gaming addiction was stronger for high than for low impulsivity adolescents. These findings underscore the importance of integrating the biosocial-affect model and the Dual Systems Model to understand how and when sensation seeking impacts adolescent online gaming addiction.

  12. Sensation Seeking and Online Gaming Addiction in Adolescents: A Moderated Mediation Model of Positive Affective Associations and Impulsivity

    Directory of Open Access Journals (Sweden)

    Jianping Hu

    2017-05-01

    Full Text Available Based on the Dual Systems Model (Somerville et al., 2010; Steinberg, 2010a and the biosocial-affect model (Romer and Hennessy, 2007 of adolescent sensation seeking and problem behaviors, the present study examined how (affective associations with online games as a mediator and when (impulsivity as a moderator did sensation seeking influence online gaming addiction in adolescence. A total of 375 Chinese male adolescents (mean age = 16.02 years, SD = 0.85 from southern China completed anonymous questionnaires regarding sensation seeking, positive affective associations with online games, impulsivity, and online gaming addiction. Our findings revealed that sensation seeking, positive affective associations with online games and impulsivity were each significantly and positively associated with online gaming addiction in adolescents. Positive affective associations mediated the relationship between sensation seeking and online gaming addiction. Further, impulsivity moderated the relationship between positive affective associations and online gaming addiction, such that the association between positive affective association and online gaming addiction was stronger for high than for low impulsivity adolescents. These findings underscore the importance of integrating the biosocial-affect model and the Dual Systems Model to understand how and when sensation seeking impacts adolescent online gaming addiction.

  13. Sensation Seeking and Online Gaming Addiction in Adolescents: A Moderated Mediation Model of Positive Affective Associations and Impulsivity

    Science.gov (United States)

    Hu, Jianping; Zhen, Shuangju; Yu, Chengfu; Zhang, Qiuyan; Zhang, Wei

    2017-01-01

    Based on the Dual Systems Model (Somerville et al., 2010; Steinberg, 2010a) and the biosocial-affect model (Romer and Hennessy, 2007) of adolescent sensation seeking and problem behaviors, the present study examined how (affective associations with online games as a mediator) and when (impulsivity as a moderator) did sensation seeking influence online gaming addiction in adolescence. A total of 375 Chinese male adolescents (mean age = 16.02 years, SD = 0.85) from southern China completed anonymous questionnaires regarding sensation seeking, positive affective associations with online games, impulsivity, and online gaming addiction. Our findings revealed that sensation seeking, positive affective associations with online games and impulsivity were each significantly and positively associated with online gaming addiction in adolescents. Positive affective associations mediated the relationship between sensation seeking and online gaming addiction. Further, impulsivity moderated the relationship between positive affective associations and online gaming addiction, such that the association between positive affective association and online gaming addiction was stronger for high than for low impulsivity adolescents. These findings underscore the importance of integrating the biosocial-affect model and the Dual Systems Model to understand how and when sensation seeking impacts adolescent online gaming addiction. PMID:28529494

  14. Near-Nash equilibrium strategies for LQ differential games with inaccurate state information

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available ε -Nash equilibrium or “near equilibrium” for a linear quadratic cost game is considered. Due to inaccurate state information, the standard solution for feedback Nash equilibrium cannot be applied. Instead, an estimation of the players' states is substituted into the optimal control strategies equation obtained for perfect state information. The magnitude of the ε in the ε -Nash equilibrium will depend on the quality of the estimation process. To illustrate this approach, a Luenberger-type observer is used in the numerical example to generate the players' state estimates in a two-player non-zero-sum LQ differential game.

  15. Stochastic Perron's method and elementary strategies for zero-sum differential games

    OpenAIRE

    Sîrbu, Mihai

    2013-01-01

    We develop here the Stochastic Perron Method in the framework of two-player zero-sum differential games. We consider the formulation of the game where both players play, symmetrically, feed-back strategies (as in [CR09] or [PZ12]) as opposed to the Elliott-Kalton formulation prevalent in the literature. The class of feed-back strategies we use is carefully chosen so that the state equation admits strong solutions and the technicalities involved in the Stochastic Perron Method carry through in...

  16. The position value for partition function form network games

    NARCIS (Netherlands)

    Nouweland, van den C.G.A.M.; Slikker, M.

    We use the axiomatization of the position value for network situations in van den Nouweland and Slikker (2012) to define a position value for partition function form network situations. We do this by generalizing the axioms to the partition function form value function setting as studied in Navarro

  17. Corporate brand positioning and differentiation in the luxury automotive industry

    OpenAIRE

    Kotiranta, V. (Ville)

    2017-01-01

    Abstract Global luxury automotive industry faces one of the most competitive and dynamic markets in the world. The focus of this research has been to discover the corporate strategies relating to competitive positioning and differentiation via brand personality. Both Aaker brand personality framework and specifically for this industry developed luxury automotive strategy framework are applied for content analysis data, whic...

  18. The problem of false positives and false negatives in violent video game experiments.

    Science.gov (United States)

    Ferguson, Christopher J

    The problem of false positives and negatives has received considerable attention in behavioral research in recent years. The current paper uses video game violence research as an example of how such issues may develop in a field. Despite decades of research, evidence on whether violent video games (VVGs) contribute to aggression in players has remained mixed. Concerns have been raised in recent years that experiments regarding VVGs may suffer from both "false positives" and "false negatives." The current paper examines this issue in three sets of video game experiments, two sets of video game experiments on aggression and prosocial behaviors identified in meta-analysis, and a third group of recent null studies. Results indicated that studies of VVGs and aggression appear to be particularly prone to false positive results. Studies of VVGs and prosocial behavior, by contrast are heterogeneous and did not demonstrate any indication of false positive results. However, their heterogeneous nature made it difficult to base solid conclusions on them. By contrast, evidence for false negatives in null studies was limited, and little evidence emerged that null studies lacked power in comparison those highlighted in past meta-analyses as evidence for effects. These results are considered in light of issues related to false positives and negatives in behavioral science more broadly. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Oscillations of centroid position and surface area of soccer teams in small-sided games

    NARCIS (Netherlands)

    Frencken, Wouter; Lemmink, Koen; Delleman, Nico; Visscher, Chris

    2011-01-01

    There is a need for a collective variable that captures the dynamics of team sports like soccer at match level. The centroid positions and surface areas of two soccer teams potentially describe the coordinated flow of attacking and defending in small-sided soccer games at team level. The aim of the

  20. Using Games to Promote Girls' Positive Attitudes toward Technology

    Science.gov (United States)

    Van Eck, Richard

    2006-01-01

    Studies show that women make up only 35% of the IT workforce, and the schism between boys' and girls' interests in math and science is well documented. Richard Van Eck suggests that providing girls with more positive experiences with technology may impact their overall attitudes toward technology and perhaps even toward math and science. Van Eck…

  1. The Physiologic and Behavioral Implications of Playing Active and Sedentary Video Games in a Seated and Standing Position.

    Science.gov (United States)

    Sanders, Gabriel J; Rebold, Michael; Peacock, Corey A; Williamson, Meagan L; Santo, Antonio S; Barkley, Jacob E

    Previous studies have assessed physiologic response while playing video games per manufacturer instructions with participants standing during active video game play and seated during sedentary game play. It is not known whether an assigned seated or standing position affects positional preference and oxygen consumption (VO2) while gaming. The purpose of the study was to assess VO2 and preference of playing active and sedentary video games in a seated and standing position. VO2 was assessed in 25 participants during four, 20-minute conditions; resting, PlayStation 2 Madden NFL Football 2011, Nintendo Wii-Sports Boxing and Nintendo Wii Madden NFL Football 2011. Each condition was divided into two positional conditions (10 minutes seated, 10 minutes standing) and each participant indicated their positional preference after each 20-minute condition. Standing VO2 (4.4 ± 0.2 ml • kg-1 • min-1 PS2, 4.6 ± 0.1 ml • kg-1 • min-1 Wii Madden, 6.8 ± 0.3 ml • kg-1 • min-1Wii Boxing) was significantly (p ≤ 0.001) greater than seated VO2 (4.0 ± 0.1 ml • kg-1 • min-1 PS2, 4.2 ± 0.1 ml • kg-1 • min-1 Wii Madden, 6.1 ± 0.3 ml • kg-1 • min-1Wii Boxing) for each gaming condition. Participants preferred (p ≤ 0.001) to sit for all gaming conditions except Wii Boxing. Playing video games while standing increases VO2 to a greater extent than playing the same games in a seated position. Standing was only preferred for the most physiologically challenging game, Wii Boxing. Gaming position should be considered when assessing the physiologic and behavioral outcomes of playing video games.

  2. Robust optimal control design using a differential game approach for open-loop linear quadratic descriptor systems

    NARCIS (Netherlands)

    Musthofa, M.W.; Salmah, S.; Engwerda, Jacob; Suparwanto, A.

    This paper studies the robust optimal control problem for descriptor systems. We applied differential game theory to solve the disturbance attenuation problem. The robust control problem was converted into a reduced ordinary zero-sum game. Within a linear quadratic setting, we solved the problem for

  3. Exploring the impact of positive and negative emotions on cooperative behaviour in a Prisoner's Dilemma Game.

    Science.gov (United States)

    Kjell, Oscar N E; Thompson, Sam

    2013-12-19

    Objective. To explore the influences of discrete positive and negative emotions on cooperation in the context of a social dilemma game. Design. Two controlled studies were undertaken. In Study 1, 69 participants were randomly assigned to an essay emotion manipulation task designed to induce either guilt, joy or no strong emotion. In Study 2, 95 participants were randomly assigned to one of the same three tasks, and the impact of emotional condition on cooperation was explored using a repeated Prisoner's Dilemma Game. Results. Study 1 established that the manipulation task was successful in inducing the specified emotions. The analysis from Study 2 revealed no significant main effects for emotions, in contrast to previous research. However, there was a significant effect for participants' pre-existing tendency to cooperate (social value orientation; SVO). Conclusion. Methodological explanations for the result are explored, including the possible impact of trial-and-error strategies, different cooperation games and endogenous vs exogenous emotions.

  4. Optimal Extraction and Taxation of Strategic Natural Resources: A Differential Game Approach

    OpenAIRE

    Pemy, Moustapha

    2016-01-01

    This paper studies the optimal extraction and taxation of nonrenewable natural resources. It is well known the market values of the main strategic resources such as oil, natural gas, uranium, copper,...,etc, fluctuate randomly following global and seasonal macro-economic parameters, these values are modeled using Markov switching L\\'evy processes. We formulate this problem as a differential game where the two players are the mining company whose aim is to maximize the revenues generated from ...

  5. Multiple Positive Solutions for Nonlinear Semipositone Fractional Differential Equations

    Directory of Open Access Journals (Sweden)

    Wen-Xue Zhou

    2012-01-01

    Full Text Available We present some new multiplicity of positive solutions results for nonlinear semipositone fractional boundary value problem D0+αu(t=p(tf(t,u(t-q(t,0differentiation. One example is also given to illustrate the main result.

  6. Positive Solutions for Coupled Nonlinear Fractional Differential Equations

    Directory of Open Access Journals (Sweden)

    Wenning Liu

    2014-01-01

    Full Text Available We consider the existence of positive solutions for a coupled system of nonlinear fractional differential equations with integral boundary values. Assume the nonlinear term is superlinear in one equation and sublinear in the other equation. By constructing two cones K1, K2 and computing the fixed point index in product cone K1×K2, we obtain that the system has a pair of positive solutions. It is remarkable that it is established on the Cartesian product of two cones, in which the feature of two equations can be opposite.

  7. Differential effects of arousal in positive and negative autobiographical memories.

    Science.gov (United States)

    Ford, Jaclyn Hennessey; Addis, Donna Rose; Giovanello, Kelly S

    2012-01-01

    Autobiographical memories are characterised by a range of emotions and emotional reactions. Recent research has demonstrated that differences in emotional valence (positive vs. negative emotion) and arousal (the degree of emotional intensity) differentially influence the retrieved memory narrative. Although the mnemonic effects of valence and arousal have both been heavily studied, it is currently unclear whether the effects of emotional arousal are equivalent for positive and negative autobiographical events. In the current study, multilevel models were used to examine differential effects of emotional valence and arousal on the richness of autobiographical memory retrieval both between and within subjects. Thirty-four young adults were asked to retrieve personal autobiographical memories associated with popular musical cues and to rate the valence, arousal and richness of these events. The multilevel analyses identified independent influences of valence and intensity upon retrieval characteristics at the within- and between-subject levels. In addition, the within-subject interactions between valence and arousal highlighted differential effects of arousal for positive and negative memories. These findings have important implications for future studies of emotion and memory, highlighting the importance of considering both valence and arousal when examining the role emotion plays in the richness of memory representation.

  8. Nash equilibrium in differential games and the construction of the programmed iteration method

    International Nuclear Information System (INIS)

    Averboukh, Yurii V

    2011-01-01

    This work is devoted to the study of nonzero-sum differential games. The set of payoffs in a situation of Nash equilibrium is examined. It is shown that the set of payoffs in a situation of Nash equilibrium coincides with the set of values of consistent functions which are fixed points of the program absorption operator. A condition for functions to be consistent is given in terms of the weak invariance of the graph of the functions under a certain differential inclusion. Bibliography: 18 titles.

  9. European dominant position and american monopolization: a unifying approach from basic game theory

    Directory of Open Access Journals (Sweden)

    Pier Luigi Parcu

    2006-06-01

    Full Text Available In this paper we explore the meaning of some fundamental legal definitions of Europeanand American antitrust using basic concepts of game theory. Important definitions in EU law likedominant position of a firm, abuse of such a dominant position, special responsibility of thedominant firm, or in US law like monopoly or monopolization offence, acquire more precisemeaning and operational content. Moreover they look closer than usually contended.In a competition game, in which there is a truly monopolistic/dominant firm (MDF andcompetition law is respected, we state in a formal theorem that an MDF has a dominant strategy, soits choices should never be a source of ex post regret. Other players of the game, understanding andanticipating the realization of this dominant strategy, will optimize their behaviour taking it intoaccount and thus be more able to select a best solution among all possible outcomes.In this context which kind of behaviours can an MDF adopt to defend its market shares andeconomic position? Following the US Supreme Court and EU Court of Justice an MDF mustcompete using normal methods of competition, superior product or business acumen, therefore weargue that market power, whatever its origin, can be defended only through competition on themerit. This definition has practical consequences: unpredictable behaviours and actions that anormal firm would not adopt might be identified as illegal abuses of dominant position ormonopolization offences, also this idea is formalized in a theorem.

  10. Positive Surgical Margins in Favorable-Stage Differentiated Thyroid Cancer.

    Science.gov (United States)

    Mercado, Catherine E; Drew, Peter A; Morris, Christopher G; Dziegielewski, Peter T; Mendenhall, William M; Amdur, Robert J

    2018-04-16

    The significance of positive margin in favorable-stage well-differentiated thyroid cancer is controversial. We report outcomes of positive-margin patients with a matched-pair comparison to a negative-margin group. A total of 25 patients with classic-histology papillary or follicular carcinoma, total thyroidectomy +/- node dissection, stage T1-3N0-1bM0, positive surgical margin at primary site, adjuvant radioactive iodine (I-131), and age older than 18 years were treated between 2003 and 2013. Endpoints were clinical and biochemical (thyroglobulin-only) recurrence-free survival. Matched-pair analysis involved a 1:1 match with negative-margin cases matched for overall stage and I-131 dose. Recurrence-free survival in positive-margin patients was 71% at 10 years. No patient was successfully salvaged with additional treatment. Only 1 patient died of thyroid cancer. Recurrence-free survival at 10 years was worse with a positive (71%) versus negative (90%) margin (P=0.140). Cure with a microscopically positive margin was suboptimal (71%) despite patients having classic-histology papillary and follicular carcinoma, favorable stage, and moderate-dose I-131 therapy.

  11. Indoor positioning using differential Wi-Fi lateration

    Science.gov (United States)

    Retscher, Guenther; Tatschl, Thomas

    2017-12-01

    For Wi-Fi positioning usually location fingerprinting or (tri)lateration are employed whereby the received signal strengths (RSSs) of the surrounding Wi-Fi Access Points (APs) are scanned on the mobile devices and used to perform localization. Within the scope of this study, the position of a mobile user is determined on the basis of lateration. Two new differential approaches are developed and compared to two common models, i.e., the one-slope and multi-wall model, for the conversion of the measured RSS of the Wi-Fi signals into ranges. The two novel methods are termed DWi-Fi as they are derived either from the well-known DGPS or VLBI positioning principles. They make use of a network of reference stations deployed in the area of interest. From continuous RSS observations on these reference stations correction parameters are derived and applied by the user in real-time. This approach leads to a reduced influence of temporal and spatial variations and various propagation effects on the positioning result. In practical use cases conducted in a multi-storey office building with three different smartphones, it is proven that the two DWi-Fi approaches outperform the common models as static positioning yielded to position errors of about 5 m in average under good spatial conditions.

  12. Superdiffusions and positive solutions of nonlinear partial differential equations

    CERN Document Server

    Dynkin, E B

    2004-01-01

    This book is devoted to the applications of probability theory to the theory of nonlinear partial differential equations. More precisely, it is shown that all positive solutions for a class of nonlinear elliptic equations in a domain are described in terms of their traces on the boundary of the domain. The main probabilistic tool is the theory of superdiffusions, which describes a random evolution of a cloud of particles. A substantial enhancement of this theory is presented that can be of interest for everybody who works on applications of probabilistic methods to mathematical analysis.

  13. Linear Pursuit Differential Game under Phase Constraint on the State of Evader

    Directory of Open Access Journals (Sweden)

    Askar Rakhmanov

    2016-01-01

    Full Text Available We consider a linear pursuit differential game of one pursuer and one evader. Controls of the pursuer and evader are subjected to integral and geometric constraints, respectively. In addition, phase constraint is imposed on the state of evader, whereas pursuer moves throughout the space. We say that pursuit is completed, if inclusion y(t1-x(t1∈M is satisfied at some t1>0, where x(t and y(t are states of pursuer and evader, respectively, and M is terminal set. Conditions of completion of pursuit in the game from all initial points of players are obtained. Strategy of the pursuer is constructed so that the phase vector of the pursuer first is brought to a given set, and then pursuit is completed.

  14. The Dynamic Programming Method of Stochastic Differential Game for Functional Forward-Backward Stochastic System

    Directory of Open Access Journals (Sweden)

    Shaolin Ji

    2013-01-01

    Full Text Available This paper is devoted to a stochastic differential game (SDG of decoupled functional forward-backward stochastic differential equation (FBSDE. For our SDG, the associated upper and lower value functions of the SDG are defined through the solution of controlled functional backward stochastic differential equations (BSDEs. Applying the Girsanov transformation method introduced by Buckdahn and Li (2008, the upper and the lower value functions are shown to be deterministic. We also generalize the Hamilton-Jacobi-Bellman-Isaacs (HJBI equations to the path-dependent ones. By establishing the dynamic programming principal (DPP, we derive that the upper and the lower value functions are the viscosity solutions of the corresponding upper and the lower path-dependent HJBI equations, respectively.

  15. USE OF A NOVEL BOARD GAME IN A CLINICAL ROTATION FOR LEARNING THORACIC DIFFERENTIAL DIAGNOSES IN VETERINARY MEDICAL IMAGING.

    Science.gov (United States)

    Ober, Christopher P

    2017-03-01

    When confronted with various findings on thoracic radiographs, fourth-year veterinary students often have difficulty generating appropriate lists of differential diagnoses. The purpose of this one-group, pretest, posttest experimental study was to determine if a game could be used as an adjunct teaching method to improve students' understanding of connections between imaging findings and differential diagnoses. A novel board game focusing on differential diagnoses in thoracic radiography was developed. One hundred fourth-year veterinary students took a brief pretest, played the board game, and took a brief posttest as a part of their respective clinical radiology rotations. Pretest results were compared to posttest results using a paired t-test to determine if playing the game impacted student understanding. Students' mean scores on the posttest were significantly higher than mean pretest scores (P game resulted in improved short-term understanding of thoracic differential diagnoses by fourth-year students, and use of the board game on a clinical rotation seems to be a beneficial part of the learning process. © 2016 American College of Veterinary Radiology.

  16. Violent and nonviolent video games differentially affect physical aggression for individuals high vs. low in dispositional anger.

    Science.gov (United States)

    Engelhardt, Christopher R; Bartholow, Bruce D; Saults, J Scott

    2011-01-01

    Although numerous experiments have shown that exposure to violent video games (VVG) causes increases in aggression, relatively few studies have investigated the extent to which this effect differs as a function of theoretically relevant individual difference factors. This study investigated whether video game content differentially influences aggression as a function of individual differences in trait anger. Participants were randomly assigned to play a violent or nonviolent video game before completing a task in which they could behave aggressively. Results showed that participants high in trait anger were the most aggressive, but only if they first played a VVG. This relationship held while statistically controlling for dimensions other than violent content on which game conditions differed (e.g. frustration, arousal). Implications of these findings for models explaining the effects of video games on behavior are discussed. © 2011 Wiley Periodicals, Inc.

  17. Governance Mechanism for Global Greenhouse Gas Emissions: A Stochastic Differential Game Approach

    Directory of Open Access Journals (Sweden)

    Wei Yu

    2013-01-01

    Full Text Available Today developed and developing countries have to admit the fact that global warming is affecting the earth, but the fundamental problem of how to divide up necessary greenhouse gas reductions between developed and developing countries remains. In this paper, we propose cooperative and noncooperative stochastic differential game models to describe greenhouse gas emissions decision makings of developed and developing countries, calculate their feedback Nash equilibrium and the Pareto optimal solution, characterize parameter spaces that developed and developing countries can cooperate, design cooperative conditions under which participants buy the cooperative payoff, and distribute the cooperative payoff with Nash bargaining solution. Lastly, numerical simulations are employed to illustrate the above results.

  18. Active Healthy Kids Canada's Position on Active Video Games for Children and Youth.

    Science.gov (United States)

    Chaput, Jean-Philippe; Leblanc, Allana G; McFarlane, Allison; Colley, Rachel C; Thivel, David; Biddle, Stuart Jh; Maddison, Ralph; Leatherdale, Scott T; Tremblay, Mark S

    2013-12-01

    The effect of active video games (AVGs) on acute energy expenditure has previously been reported; however, the influence of AVGs on other health-related lifestyle indicators remains unclear. To address this knowledge gap, Active Healthy Kids Canada (AHKC) convened an international group of researchers to conduct a systematic review to understand whether AVGs should be promoted to increase physical activity and improve health indicators in children and youth (zero to 17 years of age). The present article outlines the process and outcomes of the development of the AHKC's position on active video games for children and youth. In light of the available evidence, AHKC does not recommend AVGs as a strategy to help children be more physically active. However, AVGs may exchange some sedentary time for light- to moderate-intensity physical activity, and there may be specific situations in which AVGs provide benefit (eg, motor skill development in special populations and rehabilitation).

  19. Modeling and Computation of Transboundary Industrial Pollution with Emission Permits Trading by Stochastic Differential Game.

    Science.gov (United States)

    Chang, Shuhua; Wang, Xinyu; Wang, Zheng

    2015-01-01

    Transboundary industrial pollution requires international actions to control its formation and effects. In this paper, we present a stochastic differential game to model the transboundary industrial pollution problems with emission permits trading. More generally, the process of emission permits price is assumed to be stochastic and to follow a geometric Brownian motion (GBM). We make use of stochastic optimal control theory to derive the system of Hamilton-Jacobi-Bellman (HJB) equations satisfied by the value functions for the cooperative and the noncooperative games, respectively, and then propose a so-called fitted finite volume method to solve it. The efficiency and the usefulness of this method are illustrated by the numerical experiments. The two regions' cooperative and noncooperative optimal emission paths, which maximize the regions' discounted streams of the net revenues, together with the value functions, are obtained. Additionally, we can also obtain the threshold conditions for the two regions to decide whether they cooperate or not in different cases. The effects of parameters in the established model on the results have been also examined. All the results demonstrate that the stochastic emission permits prices can motivate the players to make more flexible strategic decisions in the games.

  20. Modeling and Computation of Transboundary Industrial Pollution with Emission Permits Trading by Stochastic Differential Game.

    Directory of Open Access Journals (Sweden)

    Shuhua Chang

    Full Text Available Transboundary industrial pollution requires international actions to control its formation and effects. In this paper, we present a stochastic differential game to model the transboundary industrial pollution problems with emission permits trading. More generally, the process of emission permits price is assumed to be stochastic and to follow a geometric Brownian motion (GBM. We make use of stochastic optimal control theory to derive the system of Hamilton-Jacobi-Bellman (HJB equations satisfied by the value functions for the cooperative and the noncooperative games, respectively, and then propose a so-called fitted finite volume method to solve it. The efficiency and the usefulness of this method are illustrated by the numerical experiments. The two regions' cooperative and noncooperative optimal emission paths, which maximize the regions' discounted streams of the net revenues, together with the value functions, are obtained. Additionally, we can also obtain the threshold conditions for the two regions to decide whether they cooperate or not in different cases. The effects of parameters in the established model on the results have been also examined. All the results demonstrate that the stochastic emission permits prices can motivate the players to make more flexible strategic decisions in the games.

  1. Positive solutions of fractional differential equations with derivative terms

    Directory of Open Access Journals (Sweden)

    Cuiping Cheng

    2012-11-01

    Full Text Available In this article, we are concerned with the existence of positive solutions for nonlinear fractional differential equation whose nonlinearity contains the first-order derivative, $$displaylines{ D_{0^+}^{alpha}u(t+f(t,u(t,u'(t=0,quad tin (0,1,; n-14 $ $(ninmathbb{N}$, $D_{0^+}^{alpha}$ is the standard Riemann-Liouville fractional derivative of order $alpha$ and $f(t,u,u':[0,1] imes [0,inftyimes(-infty,+infty o [0,infty$ satisfies the Caratheodory type condition. Sufficient conditions are obtained for the existence of at least one or two positive solutions by using the nonlinear alternative of the Leray-Schauder type and Krasnosel'skii's fixed point theorem. In addition, several other sufficient conditions are established for the existence of at least triple, n or 2n-1 positive solutions. Two examples are given to illustrate our theoretical results.

  2. Algorithm for Overcoming the Curse of Dimensionality for Certain Non-convex Hamilton-Jacobi Equations, Projections and Differential Games

    Science.gov (United States)

    2016-05-01

    0.5 × 10−8. Our algorithm is implemented in C++ on an 1.7 GHz Intel Core i7-4650U CPU. Linear algebra packages BLAS [40] and LAPACK [41] are used to...subproblems. Our approach is expected to have wide applications in continuous dynamic games, control theory problems, and elsewhere. Mathematics...differential dynamic games, control theory problems, and dynamical systems coming from the physical world, e.g. [11]. An important application is to

  3. Computation of Value Functions in Nonlinear Differential Games with State Constraints

    KAUST Repository

    Botkin, Nikolai

    2013-01-01

    Finite-difference schemes for the computation of value functions of nonlinear differential games with non-terminal payoff functional and state constraints are proposed. The solution method is based on the fact that the value function is a generalized viscosity solution of the corresponding Hamilton-Jacobi-Bellman-Isaacs equation. Such a viscosity solution is defined as a function satisfying differential inequalities introduced by M. G. Crandall and P. L. Lions. The difference with the classical case is that these inequalities hold on an unknown in advance subset of the state space. The convergence rate of the numerical schemes is given. Numerical solution to a non-trivial three-dimensional example is presented. © 2013 IFIP International Federation for Information Processing.

  4. Stability and Linear Quadratic Differential Games of Discrete-Time Markovian Jump Linear Systems with State-Dependent Noise

    Directory of Open Access Journals (Sweden)

    Huiying Sun

    2014-01-01

    Full Text Available We mainly consider the stability of discrete-time Markovian jump linear systems with state-dependent noise as well as its linear quadratic (LQ differential games. A necessary and sufficient condition involved with the connection between stochastic Tn-stability of Markovian jump linear systems with state-dependent noise and Lyapunov equation is proposed. And using the theory of stochastic Tn-stability, we give the optimal strategies and the optimal cost values for infinite horizon LQ stochastic differential games. It is demonstrated that the solutions of infinite horizon LQ stochastic differential games are concerned with four coupled generalized algebraic Riccati equations (GAREs. Finally, an iterative algorithm is presented to solve the four coupled GAREs and a simulation example is given to illustrate the effectiveness of it.

  5. Nonzero-Sum Stochastic Differential Portfolio Games under a Markovian Regime Switching Model

    Directory of Open Access Journals (Sweden)

    Chaoqun Ma

    2015-01-01

    Full Text Available We consider a nonzero-sum stochastic differential portfolio game problem in a continuous-time Markov regime switching environment when the price dynamics of the risky assets are governed by a Markov-modulated geometric Brownian motion (GBM. The market parameters, including the bank interest rate and the appreciation and volatility rates of the risky assets, switch over time according to a continuous-time Markov chain. We formulate the nonzero-sum stochastic differential portfolio game problem as two utility maximization problems of the sum process between two investors’ terminal wealth. We derive a pair of regime switching Hamilton-Jacobi-Bellman (HJB equations and two systems of coupled HJB equations at different regimes. We obtain explicit optimal portfolio strategies and Feynman-Kac representations of the two value functions. Furthermore, we solve the system of coupled HJB equations explicitly in a special case where there are only two states in the Markov chain. Finally we provide comparative statics and numerical simulation analysis of optimal portfolio strategies and investigate the impact of regime switching on optimal portfolio strategies.

  6. Brand positioning strategies : an expiremental test ot two types of benefit differentiation

    OpenAIRE

    Hem, Alexander Farestvedt; Teslo, Per Christian Strand

    2012-01-01

    The purpose of this study is to examine associative- and instrumental benefit differentiation based on secondary associations as part of brand positioning. The field of brand positioning has been subject to extensive research, however, differentiation based on secondary associations and differences between instrumental- and associative benefit differentiation has received less attention. Instrumental benefit differentiation relates to benefits that are linked directly to product performance, ...

  7. Helicopter Approach Capability Using the Differential Global Positioning System

    Science.gov (United States)

    Kaufmann, David N.

    1994-01-01

    The results of flight tests to determine the feasibility of using the Global Positioning System (GPS) in the Differential mode (DGPS) to provide high accuracy, precision navigation and guidance for helicopter approaches to landing are presented. The airborne DGPS receiver and associated equipment is installed in a NASA UH-60 Black Hawk helicopter. The ground-based DGPS reference receiver is located at a surveyed test site and is equipped with a real-time VHF data link to transmit correction information to the airborne DGPS receiver. The corrected airborne DGPS information, together with the preset approach geometry, is used to calculate guidance commands which are sent to the aircraft's approach guidance instruments. The use of DGPS derived guidance for helicopter approaches to landing is evaluated by comparing the DGPS data with the laser tracker truth data. The errors indicate that the helicopter position based on DGPS guidance satisfies the International Civil Aviation Organization (ICAO) Category 1 (CAT 1) lateral and vertical navigational accuracy requirements.

  8. The Use of Player-centered Positive Reinforcement to Schedule In-game Rewards Increases Enjoyment and Performance in a Serious Game

    Directory of Open Access Journals (Sweden)

    Aniket Nagle

    2014-10-01

    Full Text Available Among the methods used to increase enjoyment and performance in serious games, reward schedules, i.e., determining when in-game rewards should be given, have not been sufficiently explored. In the present study, we designed a simple memory training serious game and compared two methods of scheduling rewards, both based on the paradigm of positive reinforcement: fixed ratio schedule, in which rewards were given after a fixed number of correct responses, and variable ratio schedule, in which rewards were given after an unpredictable number of correct responses. To account for the variability in player preference for rewards, a player-centered sub-mode was included in both schedules by adjusting the schedule ratio according to player preference for rewards. The effectiveness of this approach was tested by comparing it against two more sub-modes: one which used a predetermined ratio, and another which set the ratio to the opposite of player preference. The game was put online and tested with 210 participants. Enjoyment, performance, duration of gameplay, and likelihood to play again were significantly higher in the player-centered sub-mode than the other sub-modes. On average, the variable-ratio schedule was better in the outcome measures than the fixed-ratio schedule. The results highlight the importance of in-game rewards, and indicate that giving rewards according to a player-centered variable-ratio schedule has the potential to make serious games more effective.

  9. Gaming

    CERN Document Server

    Duke, Richard D

    2014-01-01

    Als Richard Duke sein Buch ""Gaming: The Future's Language"" 1974 veröffentlichte, war er ein Pionier für die Entwicklung und Anwendung von Planspielen in Politik, Strategieentwicklung und Management. Das Buch wurde zu einem viel zitierten Standardwerk. 2014 feiert die von Richard D. Duke gegründete International Simulation and Gaming Association (ISAGA) ihr 45-jähriges Bestehen. Gleichzeitig legt Richard D. Duke eine überarbeitete Auflage seines Klassikers vor.   Inhaltsverzeichnis TABLE OF CONTENTSAcknowledgments Preface SECTION I1. The ProblemSECTION II2. Modes of Human Communication3. Mode

  10. Knowing You, Knowing Me (KYKM: An interactive game to address positive mother-daughter communication and relationships.

    Directory of Open Access Journals (Sweden)

    Mary eKatsikitis

    2014-07-01

    Full Text Available This technical report describes an interactive game environment designed to bring mothers and their adolescent daughters together to discuss three issues that have previously been shown in the literature to be of concern to families, as young girls transition from middle childhood to the adolescent years. The game is called Knowing you, Knowing me or KYKM, and is used to help mothers and daughters discuss the following three topics: positive communication skills, relationship building, and managing risky behaviours in the social environment. As the game remains untested, its limitations and future implications of its utility are discussed.

  11. Knowing You, Knowing Me (KYKM): an interactive game to address positive mother-daughter communication and relationships.

    Science.gov (United States)

    Katsikitis, Mary; Jones, Christian; Muscat, Melody; Crawford, Kate

    2014-01-01

    This technical report describes an interactive game environment designed to bring mothers and their adolescent daughters together to discuss three issues that have previously been shown in the literature to be of concern to families, as young girls transition from middle childhood to the adolescent years. The game is called Knowing you, Knowing me or KYKM, and is used to help mothers and daughters discuss the following three topics: positive communication skills, relationship building, and managing risky behaviors in the social environment. As the game remains untested, its limitations and future implications of its utility are discussed.

  12. Erk1 positively regulates osteoclast differentiation and bone resorptive activity.

    Directory of Open Access Journals (Sweden)

    Yongzheng He

    Full Text Available The extracellular signal-regulated kinases (ERK1 and 2 are widely-expressed and they modulate proliferation, survival, differentiation, and protein synthesis in multiple cell lineages. Altered ERK1/2 signaling is found in several genetic diseases with skeletal phenotypes, including Noonan syndrome, Neurofibromatosis type 1, and Cardio-facio-cutaneous syndrome, suggesting that MEK-ERK signals regulate human skeletal development. Here, we examine the consequence of Erk1 and Erk2 disruption in multiple functions of osteoclasts, specialized macrophage/monocyte lineage-derived cells that resorb bone. We demonstrate that Erk1 positively regulates osteoclast development and bone resorptive activity, as genetic disruption of Erk1 reduced osteoclast progenitor cell numbers, compromised pit formation, and diminished M-CSF-mediated adhesion and migration. Moreover, WT mice reconstituted long-term with Erk1(-/- bone marrow mononuclear cells (BMMNCs demonstrated increased bone mineral density as compared to recipients transplanted with WT and Erk2(-/- BMMNCs, implicating marrow autonomous, Erk1-dependent osteoclast function. These data demonstrate Erk1 plays an important role in osteoclast functions while providing rationale for the development of Erk1-specific inhibitors for experimental investigation and/or therapeutic modulation of aberrant osteoclast function.

  13. Game-Based Curricula in Biology Classes: Differential Effects among Varying Academic Levels

    Science.gov (United States)

    Sadler, Troy D.; Romine, William L.; Stuart, Parker E.; Merle-Johnson, Dominike

    2013-01-01

    Video games have become a popular medium in our society, and recent scholarship suggests that games can support substantial learning. This study stems from a project in which we created a video game enabling students to use biotechnology to solve a societal problem. As students engaged in the game, they necessarily interacted with the underlying…

  14. Transforming youth care through online simulation gaming. Aligning the positions of practitioners and observers

    Directory of Open Access Journals (Sweden)

    Kees JM van Haaster

    2014-09-01

    Full Text Available Transforming youth care through online simulation gaming. Aligning the positions of practitioners and observersThe youth care service in the Netherlands is currently undergoing a major transition from national and regional finance and control to localized regulation and responsibility. The aim is to initiate a transformation towards greater intervention value and to support greater self-reliance in social networks. Effective youth care depends largely on the quality of the network exchange. If efficiency is our concern, we should look into the methods and techniques of network exchange. When it comes to solving hard problems, the significance of situational knowledge construction and network coordination must not be underrated. Professional deliberation is directed toward understanding, acting and analysis. We need smart and flexible ways to direct systems information from practice to network reflection, and to guide results from network consultation to practice.This article presents a proposal for a case study, as a follow-up to a recent dissertation about online simulation gaming for youth care network exchange (Van Haaster, 2014. The results of that research show that it is a valuable exercise to model intricate issues from practice using simulation game design and that youth care professionals appreciate the relevance, usability and usefulness of this new tool. The question in this paper is how to develop a practicable approach using online simulation gaming to improve patterns of action and reflection on dilemmas and hard-to-solve problems in youth care practice. Child-rearing conditions and family behaviour are usually enhanced through sequences of exploration, experimentation and evaluation. Step-by-step progressions are characterized by balancing acting and thinking. The author elaborates this observation through a model that alternates acting in practice with retrospect and prospect reflection in online game sessions

  15. ON A COURNOT DUOPOLY GAME WITH DIFFERENTIATED GOODS, HETEROGENEOUS EXPECTATIONS AND A COST FUNCTION INCLUDING EMISSION COSTS

    Directory of Open Access Journals (Sweden)

    Georges SARAFOPOULOS

    2017-07-01

    Full Text Available In this study we investigate the dynamics of a nonlinear Cournot- type duopoly game with differentiated goods, linear demand and a cost function that includes emission costs. The game is modeled with a system of two difference equations. Existence and stability of equilibria of this system are studied. We show that the model gives more complex chaotic and unpredictable trajectories as a consequence of change in the parameter of horizontal product differentiation and a higher (lower degree of product differentiation (weaker or fiercer competition destabilize (stabilize the economy. The chaotic features are justified numerically via computing Lyapunov numbers and sensitive dependence on initial conditions. Also, we show that in this case there are stable trajectories and a higher (lower degree of product differentiation does not tend to destabilize the economy.

  16. Game theory and its role in determining optimal policies and strategic interaction between fiscal and monetary policymakers : (Application of differential game theory and stackelberg games)

    NARCIS (Netherlands)

    Mahmoudinia, D.; Esfahani, Rahim Dalali; Engwerda, Jacob; Dastjerdi, R.B.

    2016-01-01

    In this study, we follow several purpose. In the first section, the game theory concept and the formation of its fundamental concepts is examined. After that, we investigate that how von Neumann-Morgenstern (1944) and john Nash (1950-1953) works, caused the formation of modern game theory. Then, we

  17. Differential Game Analyses of Logistics Service Supply Chain Coordination by Cost Sharing Contract

    Directory of Open Access Journals (Sweden)

    Haifeng Zhao

    2014-01-01

    Full Text Available Cooperation of all the members in a supply chain plays an important role in logistics service. The service integrator can encourage cooperation from service suppliers by sharing their cost during the service, which we assume can increase the sales by accumulating the reputation of the supply chain. A differential game model is established with the logistics service supply chain that consists of one service integrator and one supplier. And we derive the optimal solutions of the Nash equilibrium without cost sharing contract and the Stackelberg equilibrium with the integrator as the leader who partially shares the cost of the efforts of the supplier. The results make the benefits of the cost sharing contract in increasing the profits of both players as well as the whole supply chain explicit, which means that the cost sharing contract is an effective coordination mechanism in the long-term relationship of the members in a logistics service supply chain.

  18. Finite-horizon differential games for missile-target interception system using adaptive dynamic programming with input constraints

    Science.gov (United States)

    Sun, Jingliang; Liu, Chunsheng

    2018-01-01

    In this paper, the problem of intercepting a manoeuvring target within a fixed final time is posed in a non-linear constrained zero-sum differential game framework. The Nash equilibrium solution is found by solving the finite-horizon constrained differential game problem via adaptive dynamic programming technique. Besides, a suitable non-quadratic functional is utilised to encode the control constraints into a differential game problem. The single critic network with constant weights and time-varying activation functions is constructed to approximate the solution of associated time-varying Hamilton-Jacobi-Isaacs equation online. To properly satisfy the terminal constraint, an additional error term is incorporated in a novel weight-updating law such that the terminal constraint error is also minimised over time. By utilising Lyapunov's direct method, the closed-loop differential game system and the estimation weight error of the critic network are proved to be uniformly ultimately bounded. Finally, the effectiveness of the proposed method is demonstrated by using a simple non-linear system and a non-linear missile-target interception system, assuming first-order dynamics for the interceptor and target.

  19. Modeling spatial navigation in the presence of dynamic obstacles: a differential games approach.

    Science.gov (United States)

    Darekar, Anuja; Goussev, Valery; McFadyen, Bradford J; Lamontagne, Anouk; Fung, Joyce

    2018-03-01

    Obstacle circumvention strategies can be shaped by the dynamic interaction of an individual (evader) and an obstacle (pursuer). We have developed a mathematical model with predictive and emergent components, using experimental data from seven healthy young adults walking toward a target while avoiding collision with a stationary or moving obstacle (approaching head-on, or diagonally 30° left or right) in a virtual environment. Two linear properties from the predictive component enable the evader to predict the minimum distance between itself and the obstacle at all times, including the future intersection of trajectories. The emergent component uses the classical differential games model to solve for an optimal circumvention while reaching the target, wherein the locomotor strategy is influenced by the obstacle, target, and the evader velocity. Both model components were fitted to a different set of experimental data obtained from five poststroke and healthy participants to derive the minimum predicted distance (predictive component) and obstacle influence dimensions (emergent component) during circumvention. Minimum predicted distance between evader and pursuer was kept constant when the evader was closest to the obstacle in all participants. Obstacle influence dimensions varied depending on obstacle approach condition and preferred side of circumvention, reflecting differences in locomotor strategies between poststroke and healthy individuals. Additionally, important associations between model outputs and observed experimental outcomes were found. The model, supported by experimental data, suggests that both predictive and emergent processes can shape obstacle circumvention strategies in healthy and poststroke individuals. NEW & NOTEWORTHY Obstacle circumvention during goal-directed locomotion is modeled with a new mathematical approach comprising both predictive and emergent elements. The major novelty is using differential games solutions to illustrate the

  20. Integrating Content and Language in Institutionally Monolingual Settings: Teacher Positioning and Differentiation

    Science.gov (United States)

    Turner, Marianne

    2017-01-01

    Translanguaging pedagogy offers a way to differentiate between students' varying linguistic repertoires when embedding an additional language across the curriculum. In this article I draw on positioning theory to show the relevance of teacher positioning to translanguaging pedagogy and differentiation. Differentiation is discussed in relation to…

  1. A Stochastic Maximum Principle for a Stochastic Differential Game of a Mean-Field Type

    Energy Technology Data Exchange (ETDEWEB)

    Hosking, John Joseph Absalom, E-mail: j.j.a.hosking@cma.uio.no [University of Oslo, Centre of Mathematics for Applications (CMA) (Norway)

    2012-12-15

    We construct a stochastic maximum principle (SMP) which provides necessary conditions for the existence of Nash equilibria in a certain form of N-agent stochastic differential game (SDG) of a mean-field type. The information structure considered for the SDG is of a possible asymmetric and partial type. To prove our SMP we take an approach based on spike-variations and adjoint representation techniques, analogous to that of S. Peng (SIAM J. Control Optim. 28(4):966-979, 1990) in the optimal stochastic control context. In our proof we apply adjoint representation procedures at three points. The first-order adjoint processes are defined as solutions to certain mean-field backward stochastic differential equations, and second-order adjoint processes of a first type are defined as solutions to certain backward stochastic differential equations. Second-order adjoint processes of a second type are defined as solutions of certain backward stochastic equations of a type that we introduce in this paper, and which we term conditional mean-field backward stochastic differential equations. From the resulting representations, we show that the terms relating to these second-order adjoint processes of the second type are of an order such that they do not appear in our final SMP equations. A comparable situation exists in an article by R. Buckdahn, B. Djehiche, and J. Li (Appl. Math. Optim. 64(2):197-216, 2011) that constructs a SMP for a mean-field type optimal stochastic control problem; however, the approach we take of using these second-order adjoint processes of a second type to deal with the type of terms that we refer to as the second form of quadratic-type terms represents an alternative to a development, to our setting, of the approach used in their article for their analogous type of term.

  2. A Stochastic Maximum Principle for a Stochastic Differential Game of a Mean-Field Type

    International Nuclear Information System (INIS)

    Hosking, John Joseph Absalom

    2012-01-01

    We construct a stochastic maximum principle (SMP) which provides necessary conditions for the existence of Nash equilibria in a certain form of N-agent stochastic differential game (SDG) of a mean-field type. The information structure considered for the SDG is of a possible asymmetric and partial type. To prove our SMP we take an approach based on spike-variations and adjoint representation techniques, analogous to that of S. Peng (SIAM J. Control Optim. 28(4):966–979, 1990) in the optimal stochastic control context. In our proof we apply adjoint representation procedures at three points. The first-order adjoint processes are defined as solutions to certain mean-field backward stochastic differential equations, and second-order adjoint processes of a first type are defined as solutions to certain backward stochastic differential equations. Second-order adjoint processes of a second type are defined as solutions of certain backward stochastic equations of a type that we introduce in this paper, and which we term conditional mean-field backward stochastic differential equations. From the resulting representations, we show that the terms relating to these second-order adjoint processes of the second type are of an order such that they do not appear in our final SMP equations. A comparable situation exists in an article by R. Buckdahn, B. Djehiche, and J. Li (Appl. Math. Optim. 64(2):197–216, 2011) that constructs a SMP for a mean-field type optimal stochastic control problem; however, the approach we take of using these second-order adjoint processes of a second type to deal with the type of terms that we refer to as the second form of quadratic-type terms represents an alternative to a development, to our setting, of the approach used in their article for their analogous type of term.

  3. Effect of video-game experience and position of flight stick controller on simulated-flight performance.

    Science.gov (United States)

    Cho, Bo-Keun; Aghazadeh, Fereydoun; Al-Qaisi, Saif

    2012-01-01

    The purpose of this study was to determine the effects of video-game experience and flight-stick position on flying performance. The study divided participants into 2 groups; center- and side-stick groups, which were further divided into high and low level of video-game experience subgroups. The experiment consisted of 7 sessions of simulated flying, and in the last session, the flight stick controller was switched to the other position. Flight performance was measured in terms of the deviation of heading, altitude, and airspeed from their respective requirements. Participants with high experience in video games performed significantly better (p increase (0.78 %). However, after switching from a center- to a side-stick controller, performance scores decreased (4.8%).

  4. Morphological profile of the best pan-american team handball players by game position

    Directory of Open Access Journals (Sweden)

    Maria Fátima Glaner

    1999-12-01

    Full Text Available The purpose of this study was to characterize the morphological variables, by game position (GP, of male athletes who participated on the X Pan-American Games in Team Handball (XPGTH and also to analyze the very same variables of the best athletes in relation to other athletes who played in the same GP. 103 athletes were measured, and the national team coaches who participated in the XPGTH selected the best seven players in the Pan-American Games, for each game position. The morphological variables characterized were: body mass; stature (ST; arm span (AS; lower extremity length (LEL; hand and wrist breadth; forearm perimeter and body composition. The results obtained demonstrated that many athletes had morphological characteristics beyond the ideal for this sport. The Z scores indicate that the best athletes from different GP (goalkeeper, backcourt, wings and circle runner exhibited larger morphological characteristics in relation to the means for the other players in their respective GP. The best goalkeeper and the circle runner were the only ones whose scores were higher in relation to each GP, respectively, when the entire group of morphological variables were considered together. The variables that demonstrated greater morphological development for the best athletesin the 4 GP, compared to the other athletes, were: ST, AS, LEL, % fat and lean body mass. ARESUMO Objetivou-se caracterizar as variáveis morfológicas dos atletas, por posição de jogo (PJ, das seleções participantes dos X Jogos Pan-Americanos de Handebol Masculino (XJPHM, e analisar as variáveis dos melhores atletas de cada PJ em relação aos demais das respectivas PJ. Mensurou-se 103 atletas. Sete deles foram selecionados por PJ, pelos treinadores das seleções participantes dos XJPHM, como os melhores da competição. Caracterizou-se as variáveis morfológicas: massa corporal; estatura (ES; envergadura (ENV; comprimento dos membros inferiores (CMI; diâmetros palmar e r

  5. The good, the bad and the ugly: a meta-analytic review of positive and negative effects of violent video games.

    Science.gov (United States)

    Ferguson, Christopher John

    2007-12-01

    Video game violence has become a highly politicized issue for scientists and the general public. There is continuing concern that playing violent video games may increase the risk of aggression in players. Less often discussed is the possibility that playing violent video games may promote certain positive developments, particularly related to visuospatial cognition. The objective of the current article was to conduct a meta-analytic review of studies that examine the impact of violent video games on both aggressive behavior and visuospatial cognition in order to understand the full impact of such games. A detailed literature search was used to identify peer-reviewed articles addressing violent video game effects. Effect sizes r (a common measure of effect size based on the correlational coefficient) were calculated for all included studies. Effect sizes were adjusted for observed publication bias. Results indicated that publication bias was a problem for studies of both aggressive behavior and visuospatial cognition. Once corrected for publication bias, studies of video game violence provided no support for the hypothesis that violent video game playing is associated with higher aggression. However playing violent video games remained related to higher visuospatial cognition (r (x) = 0.36). Results from the current analysis did not support the conclusion that violent video game playing leads to aggressive behavior. However, violent video game playing was associated with higher visuospatial cognition. It may be advisable to reframe the violent video game debate in reference to potential costs and benefits of this medium.

  6. POSITIVE SOLUTIONS TO SEMI-LINEAR SECOND-ORDER ORDINARY DIFFERENTIAL EQUATIONS IN BANACH SPACE

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In this paper,we study the existence of positive periodic solution to some second- order semi-linear differential equation in Banach space.By the fixed point index theory, we prove that the semi-linear differential equation has two positive periodic solutions.

  7. Investigating the differential effects of social networking site addiction and Internet gaming disorder on psychological health.

    Science.gov (United States)

    Pontes, Halley M

    2017-12-01

    Background and aims Previous studies focused on examining the interrelationships between social networking site (SNS) addiction and Internet gaming disorder (IGD) in isolation. Moreover, little is known about the potential simultaneous differential effects of SNS addiction and IGD on psychological health. This study investigated the interplay between these two technological addictions and ascertained how they can uniquely and distinctively contribute to increasing psychiatric distress when accounting for potential effects stemming from sociodemographic and technology-related variables. Methods A sample of 509 adolescents (53.5% males) aged 10-18 years (mean = 13.02, SD = 1.64) were recruited. Results It was found that key demographic variables can play a distinct role in explaining SNS addiction and IGD. Furthermore, it was found that SNS addiction and IGD can augment the symptoms of each other, and simultaneously contribute to deterioration of overall psychological health in a similar fashion, further highlighting potentially common etiological and clinical course between these two phenomena. Finally, the detrimental effects of IGD on psychological health were found to be slightly more pronounced than those produced by SNS addiction, a finding that warrants additional scientific scrutiny. Discussion and conclusion The implications of these results are further discussed in light of the existing evidence and debates regarding the status of technological addictions as primary and secondary disorders.

  8. Symmetric positive differential equations and first order hyperbolic systems

    International Nuclear Information System (INIS)

    Tangmanee, S.

    1981-12-01

    We prove that under some conditions the first order hyperbolic system and its associated mixed initial boundary conditions considered, for example, in Kreiss (Math. Comp. 22, 703-704 (1968)) and Kreiss and Gustafsson (Math. Comp. 26, 649-686 (1972)), can be transformed into a symmetric positive system of P.D.E.'s with admissible boundary conditions of Friedrich's type (Comm. Pure Appl. Math 11, 333-418 (1958)). (author)

  9. Absolute Position Sensing Based on a Robust Differential Capacitive Sensor with a Grounded Shield Window

    Directory of Open Access Journals (Sweden)

    Yang Bai

    2016-05-01

    Full Text Available A simple differential capacitive sensor is provided in this paper to measure the absolute positions of length measuring systems. By utilizing a shield window inside the differential capacitor, the measurement range and linearity range of the sensor can reach several millimeters. What is more interesting is that this differential capacitive sensor is only sensitive to one translational degree of freedom (DOF movement, and immune to the vibration along the other two translational DOFs. In the experiment, we used a novel circuit based on an AC capacitance bridge to directly measure the differential capacitance value. The experimental result shows that this differential capacitive sensor has a sensitivity of 2 × 10−4 pF/μm with 0.08 μm resolution. The measurement range of this differential capacitive sensor is 6 mm, and the linearity error are less than 0.01% over the whole absolute position measurement range.

  10. Technical and physical demands of small vs. large sided games in relation to playing position in elite soccer

    DEFF Research Database (Denmark)

    Dellal, A; Owen, A; Wong, D P

    2012-01-01

    positional roles participated in the study (25.3±2.4years, 182.4±2.3cm, 77.3±4.1kg; M±SD). Players completed three different conditioned small-sided 4 vs. 4 games (1 ball touch=1T, 2 ball touches=2T and Free Play=FP) as well as two friendly matches. Heart rate (HR), blood lactate ([La]), ratings of perceived...

  11. POSITIVE SOLUTIONS TO TWO TYPES OF NEUTRAL DIFFERENTIAL EQUATIONS WITH DISTRIBUTED DELAY

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    In this paper, we study two types of neutral functional differential equations with finite or unbounded distributed deviating arguments. By Banach contraction princi-ple, we obtain some sufficient conditions for the existence of positive solutions to such equations.

  12. TWIN POSITIVE PERIODIC SOLUTIONS OF FUNCTIONAL DIFFERENTIAL EQUATIONS WITH INFINITE DELAY

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In this paper, the author studies a class of nonlinear functional differential equation. By using a fixed point theorem in cones, sufficient conditions are established for the existence of twin positive periodic solutions.

  13. OSCILLATION FOR NEUTRAL DELAY DIFFERENTIAL EQUATION WITH POSITIVE AND NEGATIVE COEFFICIENTS

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In this paper, a new oscillating result is established for the first order neutral delay differential equation with positive and negative coefficients, which improves and generalizes several results in the literatures.

  14. Report to Congress : recapitalization plan for the nationwide differential global positioning system (NDGPS).

    Science.gov (United States)

    2010-06-01

    The U.S. Department of Transportation (DOT) has developed a recpitlaization plan to reduce technical, cost, and programmatic risks of the DOT-funded inland segment of the Nationwide Differential Global Positioning System (NDGPS)

  15. Differential games a mathematical theory with applications to warfare and pursuit, control and optimization

    CERN Document Server

    Isaacs, Rufus

    1999-01-01

    Definitive work draws on game theory, calculus of variations, and control theory to solve an array of problems: military, pursuit and evasion, athletic contests, many more. Detailed examples, formal calculations. 1965 edition.

  16. Multiple positive solutions to a coupled systems of nonlinear fractional differential equations.

    Science.gov (United States)

    Shah, Kamal; Khan, Rahmat Ali

    2016-01-01

    In this article, we study existence, uniqueness and nonexistence of positive solution to a highly nonlinear coupled system of fractional order differential equations. Necessary and sufficient conditions for the existence and uniqueness of positive solution are developed by using Perov's fixed point theorem for the considered problem. Further, we also established sufficient conditions for existence of multiplicity results for positive solutions. Also, we developed some conditions under which the considered coupled system of fractional order differential equations has no positive solution. Appropriate examples are also provided which demonstrate our results.

  17. The influence of game duration and playing position on intensity of exercise during match-play in elite water polo players.

    Science.gov (United States)

    Platanou, T; Geladas, N

    2006-11-01

    In this study, we assessed exercise intensity in 20 water polo games of different duration. The hypothesis that right wing players perform at a higher intensity than back and forward central players was also tested. Thirty water polo players, equally split between three field positions, participated in the study. Initially, their performance-related physiological capabilities were evaluated. Subsequently, during water polo games of short (4 x 7-min periods) or long duration (4 x 9-min periods), heart rate was monitored continuously and blood lactate concentration was measured at the end of each period. Activity patterns were also recorded using a video camera. Mean heart rate over the entire game was 156 +/- 18 beats x min(-1). Overall exercise intensity fluctuated around a value corresponding to the lactate threshold (4.03 +/- 0.96 mmol x l(-1), 86 +/- 5% of peak heart rate) and decreased (P game time (4.22 +/- 1.8 and 3.47 +/- 1.9 mmol x l(-1) in the second and fourth quarter, respectively). During the last 6 min, heart rate was higher (P games of short duration (156 +/- 3 beats x min(-1)) than in games of long duration (152 +/- 8 beats x min(-1)). Video analysis showed that the percentage of time spent in low-intensity activities (i.e. "out of game") was lower (23 vs. 26%), whereas that in high-intensity activities (i.e. "sprinting crawl") was higher (21 vs. 19%), in games of short compared with long duration. No difference was observed among players of various field positions in any of the variables examined. Thus during match-play, games of long duration produced significantly lower heart rate responses than games of short duration, and the physiological response exhibited by the players was not affected by field position. The water polo authorities should consider these results before changing game duration and coaches should prepare their athletes accordingly.

  18. EXISTENCE OF POSITIVE PERIODIC SOLUTION TO A CLASS OF NONAUTONOMOUS DIFFERENTIAL EQUATION WITH IMPULSES AND DELAY

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this paper, by fixed point theorem of Krasnoselskii, we study the positive pe- riodic solution to a class of nonautonomous differential equation with impulses and delay. Firstly, definition of periodic solution and some lemmas are stated. Then some results on the existence of positive periodic solution to the equation are obtained.

  19. Deconstructing Positive Affect in Later Life: A Differential Functionalist Analysis of Joy and Interest

    Science.gov (United States)

    Consedine, Nathan S.; Magai, Carol; King, Arlene R.

    2004-01-01

    Positive affect, an index of psychological well-being, is a known predictor of functionality and health in later life. Measures typically studied include joy, happiness, and subjective well-being, but less often interest--a positive emotion with functional properties that differ from joy or happiness. Following differential emotions theory, the…

  20. Existence of Positive Solutions to a Singular Semipositone Boundary Value Problem of Nonlinear Fractional Differential Systems

    Directory of Open Access Journals (Sweden)

    Xiaofeng Zhang

    2017-12-01

    Full Text Available In this paper, we consider the existence of positive solutions to a singular semipositone boundary value problem of nonlinear fractional differential equations. By applying the fixed point index theorem, some new results for the existence of positive solutions are obtained. In addition, an example is presented to demonstrate the application of our main results.

  1. On the Existence of Positive Solutions of a Nonlinear Differential Equation

    Directory of Open Access Journals (Sweden)

    Sonia Ben Othman

    2007-01-01

    A is a continuous function on [0,ω, positive and differentiable on (0,ω, and ψ is a nonnegative function on (0,ω×[0,∞ such that t↦tψ(x,t is continuous on [0,∞ for each x∈(0,ω. We give asymptotic behavior for positive solutions using a potential theory approach.

  2. Differential Responding by Rhesus Monkeys (Macaca mulatta and Humans (Homo sapiens to Variable Outcomes in the Assurance Game

    Directory of Open Access Journals (Sweden)

    Audrey E. Parrish

    2014-08-01

    Full Text Available Behavioral flexibility in how one responds to variable partner play can be examined using economic coordination games in which subjects play against a variety of partners and therefore may need to alter their behavior to produce the highest payoff. But how do we study this behavioral flexibility once players have settled on a response? Here, we investigated how responding by rhesus monkeys (Macaca mulatta and humans (Homo sapiens playing a computerized single-player version of a coordination game, the Assurance game, changed as a function of the variable responses (Stag/Hare generated by multiple simulations (SIMs. We were interested in whether individuals could track and differentially respond to changing frequencies of Stag and Hare play by the SIMs, especially with regard to the payoff dominant (Stag-Stag outcome, something that could not be done with real partners as they quickly settled on the Stag response. For both monkeys and humans, there was a linear relationship between proportion of Stag play by the subject and the likelihood of the Stag choice by the SIM such that both species increased their use of Stag as the SIM increased its use of the Stag response. However, humans more closely matched their proportion of Stag responses to that of the SIM, whereas monkeys adopted a different, but equally effective, strategy of exploiting the higher-paying Stag alternative. These results suggest that monkeys and humans demonstrate sensitivity to a dynamic game environment in which they encounter variable contingencies for the same response options, although they may employ different strategies to maximize reward.

  3. Video games.

    Science.gov (United States)

    Funk, Jeanne B

    2005-06-01

    The video game industry insists that it is doing everything possible to provide information about the content of games so that parents can make informed choices; however, surveys indicate that ratings may not reflect consumer views of the nature of the content. This article describes some of the currently popular video games, as well as developments that are on the horizon, and discusses the status of research on the positive and negative impacts of playing video games. Recommendations are made to help parents ensure that children play games that are consistent with their values.

  4. Exploring the impact of positive and negative emotions on cooperative behaviour in a Prisoner’s Dilemma Game

    Directory of Open Access Journals (Sweden)

    Oscar N.E. Kjell

    2013-12-01

    Full Text Available Objective. To explore the influences of discrete positive and negative emotions on cooperation in the context of a social dilemma game.Design. Two controlled studies were undertaken. In Study 1, 69 participants were randomly assigned to an essay emotion manipulation task designed to induce either guilt, joy or no strong emotion. In Study 2, 95 participants were randomly assigned to one of the same three tasks, and the impact of emotional condition on cooperation was explored using a repeated Prisoner’s Dilemma Game.Results. Study 1 established that the manipulation task was successful in inducing the specified emotions. The analysis from Study 2 revealed no significant main effects for emotions, in contrast to previous research. However, there was a significant effect for participants’ pre-existing tendency to cooperate (social value orientation; SVO.Conclusion. Methodological explanations for the result are explored, including the possible impact of trial-and-error strategies, different cooperation games and endogenous vs exogenous emotions.

  5. A Knowledge Engineering Approach to Developing Educational Computer Games for Improving Students' Differentiating Knowledge

    Science.gov (United States)

    Hwang, Gwo-Jen; Sung, Han-Yu; Hung, Chun-Ming; Yang, Li-Hsueh; Huang, Iwen

    2013-01-01

    Educational computer games have been recognized as being a promising approach for motivating students to learn. Nevertheless, previous studies have shown that without proper learning strategies or supportive models, the learning achievement of students might not be as good as expected. In this study, a knowledge engineering approach is proposed…

  6. Differential regional gray matter volumes in patients with on-line game addiction and professional gamers

    Science.gov (United States)

    Han, Doug Hyun; Lyoo, In Kyoon; Renshaw, Perry F.

    2015-01-01

    Patients with on-line game addiction (POGA) and professional video game players play video games for extended periods of time, but experience very different consequences for their on-line game play. Brain regions consisting of anterior cingulate, thalamus and occpito-temporal areas may increase the likelihood of becoming a pro-gamer or POGA. Twenty POGA, seventeen pro-gamers, and eighteen healthy comparison subjects (HC) were recruited. All magnetic resonance imaging (MRI) was performed on a 1.5 Tesla Espree MRI scanner (SIEMENS, Erlangen, Germany). Voxel-wise comparisons of gray matter volume were performed between the groups using the two-sample t-test with statistical parametric mapping (SPM5). Compared to HC, the POGA group showed increased impulsiveness and perseverative errors, and volume in left thalamus gray matter, but decreased gray matter volume in both inferior temporal gyri, right middle occipital gyrus, and left inferior occipital gyrus, compared with HC. Pro-gamers showed increased gray matter volume in left cingulate gyrus, but decreased gray matter volume in left middle occipital gyrus and right inferior temporal gyrus compared with HC. Additionally, the pro-gamer group showed increased gray matter volume in left cingulate gyrus and decreased left thalamus gray matter volume compared with the POGA group. The current study suggests that increased gray matter volumes of the left cingulate gyrus in pro-gamers and of the left thalamus in POGA may contribute to the different clinical characteristics of pro-gamers and POGA. PMID:22277302

  7. On the Asymptotic Behavior of Positive Solutions of Certain Fractional Differential Equations

    OpenAIRE

    Said R. Grace

    2015-01-01

    This paper deals with the asymptotic behavior of positive solutions of certain forced fractional differential equations of the form DcαCyt=et+ft, xt, c>1, α∈0,1, where yt=atx′t′, c0=y(c)/Γ(1) =yc, and c0 is a real constant. From the obtained results, we derive a technique which can be applied to some related fractional differential equations.

  8. Timing group delay and differential code bias corrections for BeiDou positioning

    Science.gov (United States)

    Guo, Fei; Zhang, Xiaohong; Wang, Jinling

    2015-05-01

    This article first clearly figures out the relationship between parameters of timing group delay (TGD) and differential code bias (DCB) for BDS, and demonstrates the equivalence of TGD and DCB correction models combining theory with practice. The TGD/DCB correction models have been extended to various occasions for BDS positioning, and such models have been evaluated by real triple-frequency datasets. To test the effectiveness of broadcast TGDs in the navigation message and DCBs provided by the Multi-GNSS Experiment (MGEX), both standard point positioning (SPP) and precise point positioning (PPP) tests are carried out for BDS signals with different schemes. Furthermore, the influence of differential code biases on BDS positioning estimates such as coordinates, receiver clock biases, tropospheric delays and carrier phase ambiguities is investigated comprehensively. Comparative analysis show that the unmodeled differential code biases degrade the performance of BDS SPP by a factor of two or more, whereas the estimates of PPP are subject to varying degrees of influences. For SPP, the accuracy of dual-frequency combinations is slightly worse than that of single-frequency, and they are much more sensitive to the differential code biases, particularly for the B2B3 combination. For PPP, the uncorrected differential code biases are mostly absorbed into the receiver clock bias and carrier phase ambiguities and thus resulting in a much longer convergence time. Even though the influence of the differential code biases could be mitigated over time and comparable positioning accuracy could be achieved after convergence, it is suggested to properly handle with the differential code biases since it is vital for PPP convergence and integer ambiguity resolution.

  9. Non-monotone positive solutions of second-order linear differential equations: existence, nonexistence and criteria

    Directory of Open Access Journals (Sweden)

    Mervan Pašić

    2016-10-01

    Full Text Available We study non-monotone positive solutions of the second-order linear differential equations: $(p(tx'' + q(t x = e(t$, with positive $p(t$ and $q(t$. For the first time, some criteria as well as the existence and nonexistence of non-monotone positive solutions are proved in the framework of some properties of solutions $\\theta (t$ of the corresponding integrable linear equation: $(p(t\\theta''=e(t$. The main results are illustrated by many examples dealing with equations which allow exact non-monotone positive solutions not necessarily periodic. Finally, we pose some open questions.

  10. Differential regional gray matter volumes in patients with on-line game addiction and professional gamers.

    Science.gov (United States)

    Han, Doug Hyun; Lyoo, In Kyoon; Renshaw, Perry F

    2012-04-01

    Patients with on-line game addiction (POGA) and professional video game players play video games for extended periods of time, but experience very different consequences for their on-line game play. Brain regions consisting of anterior cingulate, thalamus and occpito-temporal areas may increase the likelihood of becoming a pro-gamer or POGA. Twenty POGA, seventeen pro-gamers, and eighteen healthy comparison subjects (HC) were recruited. All magnetic resonance imaging (MRI) was performed on a 1.5 Tesla Espree MRI scanner (SIEMENS, Erlangen, Germany). Voxel-wise comparisons of gray matter volume were performed between the groups using the two-sample t-test with statistical parametric mapping (SPM5). Compared to HC, the POGA group showed increased impulsiveness and perseverative errors, and volume in left thalamus gray matter, but decreased gray matter volume in both inferior temporal gyri, right middle occipital gyrus, and left inferior occipital gyrus, compared with HC. Pro-gamers showed increased gray matter volume in left cingulate gyrus, but decreased gray matter volume in left middle occipital gyrus and right inferior temporal gyrus compared with HC. Additionally, the pro-gamer group showed increased gray matter volume in left cingulate gyrus and decreased left thalamus gray matter volume compared with the POGA group. The current study suggests that increased gray matter volumes of the left cingulate gyrus in pro-gamers and of the left thalamus in POGA may contribute to the different clinical characteristics of pro-gamers and POGA. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Gram-negative and -positive bacteria differentiation in blood culture samples by headspace volatile compound analysis.

    Science.gov (United States)

    Dolch, Michael E; Janitza, Silke; Boulesteix, Anne-Laure; Graßmann-Lichtenauer, Carola; Praun, Siegfried; Denzer, Wolfgang; Schelling, Gustav; Schubert, Sören

    2016-12-01

    Identification of microorganisms in positive blood cultures still relies on standard techniques such as Gram staining followed by culturing with definite microorganism identification. Alternatively, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry or the analysis of headspace volatile compound (VC) composition produced by cultures can help to differentiate between microorganisms under experimental conditions. This study assessed the efficacy of volatile compound based microorganism differentiation into Gram-negatives and -positives in unselected positive blood culture samples from patients. Headspace gas samples of positive blood culture samples were transferred to sterilized, sealed, and evacuated 20 ml glass vials and stored at -30 °C until batch analysis. Headspace gas VC content analysis was carried out via an auto sampler connected to an ion-molecule reaction mass spectrometer (IMR-MS). Measurements covered a mass range from 16 to 135 u including CO2, H2, N2, and O2. Prediction rules for microorganism identification based on VC composition were derived using a training data set and evaluated using a validation data set within a random split validation procedure. One-hundred-fifty-two aerobic samples growing 27 Gram-negatives, 106 Gram-positives, and 19 fungi and 130 anaerobic samples growing 37 Gram-negatives, 91 Gram-positives, and two fungi were analysed. In anaerobic samples, ten discriminators were identified by the random forest method allowing for bacteria differentiation into Gram-negative and -positive (error rate: 16.7 % in validation data set). For aerobic samples the error rate was not better than random. In anaerobic blood culture samples of patients IMR-MS based headspace VC composition analysis facilitates bacteria differentiation into Gram-negative and -positive.

  12. Absence of positive solutions to the system of differential inequalities on manifolds

    Science.gov (United States)

    Sun, Yuhua

    2018-01-01

    We investigate the nonexistence of positive solutions to a certain system of differential inequalities on a complete connected non-compact Riemannian manifold. We show that if for some reference point x0, the volume of geodesic ball μ(B(x0, r)) ≤ Crp ln q r holds for all large enough r and for some constant C, then there exists no positive solution to the system. Here the exponents p and q are sharp and cannot be relaxed.

  13. Effect of position, time in the season, and playing surface on Achilles tendon ruptures in NFL games: a 2009-10 to 2016-17 review.

    Science.gov (United States)

    Krill, Michael K; Borchers, James R; Hoffman, Joshua T; Krill, Matthew L; Hewett, Timothy E

    2017-09-01

    Achilles tendon (AT) ruptures are a potentially career-altering and ending injury. Achilles tendon ruptures have a below average return-to-play rate compared to other common orthopaedic procedures for National Football League (NFL) players. The objective of this study was to monitor the incidence and injury rates (IR) of AT ruptures that occurred during the regular season in order to evaluate the influence of player position, time of injury, and playing surface on rupture rates. A thorough online review was completed to identify published injury reports and public information regarding AT ruptures sustained during regular season and post-season games in the National Football League (NFL) during the 2009-10 to 2016-17 seasons. Team schedules, player position details and stadium information was used to determine period of the season of injury and playing surface. IRs were calculated per 100 team games (TG). Injury rate ratios (IRR) were utilized to compare IRs. During eight monitored seasons, there were 44 AT ruptures in NFL games. A majority of AT ruptures were sustained in the first eight games of the regular season (n = 32, 72.7%). There was a significant rate difference for the first and second four-game segments of the regular season compared to the last two four-game segments of the regular season. Defensive players suffered a majority of AT ruptures (n = 32, 72.7%). The IR on grass was 1.00 per 100 TG compared to 1.08 per 100 TG on artificial turf (IRR: 0.93, p = .80). A significant increase in AT ruptures occurred in the first and second four game segments of the regular season compared to the last two-four game segments of the regular season. Defensive players suffered a majority of AT ruptures compared to offensive or specialist players. There was no difference between AT rupture rates and playing surface in games.

  14. Relating specific emotions to intrinsic motivation: on the moderating role of positive and negative emotion differentiation.

    Science.gov (United States)

    Vandercammen, Leen; Hofmans, Joeri; Theuns, Peter

    2014-01-01

    Despite the fact that studies on self-determination theory have traditionally disregarded the explicit role of emotions in the motivation eliciting process, research attention for the affective antecedents of motivation is growing. We add to this emerging research field by testing the moderating role of emotion differentiation -individual differences in the extent to which people can differentiate between specific emotions- on the relationship between twelve specific emotions and intrinsic motivation. To this end, we conducted a daily diary study (N = 72) and an experience sampling study (N = 34). Results showed that the relationship between enthusiasm, cheerfulness, optimism, contentedness, gloominess, miserableness, uneasiness (in both studies 1 and 2), calmness, relaxation, tenseness, depression, worry (only in Study 1) on one hand and intrinsic motivation on the other hand was moderated by positive emotion differentiation for the positive emotions and by negative emotion differentiation for the negative emotions. Altogether, these findings suggest that for people who are unable to distinguish between different specific positive emotions the relationship between those specific positive emotions and intrinsic motivation is stronger, whereas the relationship between specific negative emotions and intrinsic motivation is weaker for people who are able to distinguish between the different specific negative emotions. Theoretical and practical implications are discussed.

  15. Differential Language Functioning of Monolinguals and Bilinguals on Positive-Negative Emotional Expression

    Science.gov (United States)

    Kheirzadeh, Shiela; Hajiabed, Mohammadreza

    2016-01-01

    The present interdisciplinary research investigates the differential emotional expression between Persian monolinguals and Persian-English bilinguals. In other words, the article was an attempt to answer the questions whether bilinguals and monolinguals differ in the expression of positive and negative emotions elicited through sad and happy…

  16. Positive Solutions for System of Nonlinear Fractional Differential Equations in Two Dimensions with Delay

    Directory of Open Access Journals (Sweden)

    Azizollah Babakhani

    2010-01-01

    Full Text Available We investigate the existence and uniqueness of positive solution for system of nonlinear fractional differential equations in two dimensions with delay. Our analysis relies on a nonlinear alternative of Leray-Schauder type and Krasnoselskii's fixed point theorem in a cone.

  17. Triple positive  solutions of nth order impulsive integro-differential equations

    Directory of Open Access Journals (Sweden)

    Zeyong Qiu

    2011-07-01

    Full Text Available In this paper, we prove the existence of at least three positive solutions of boundary value problems for nth order nonlinear impulsive integro-differential equations of mixed type on infinite interval with infinite number of impulsive times. Our results are obtained by applying a new fixed point theorem introduced by Avery and Peterson.

  18. Relating Specific Emotions to Intrinsic Motivation: On the Moderating Role of Positive and Negative Emotion Differentiation

    Science.gov (United States)

    Vandercammen, Leen; Hofmans, Joeri; Theuns, Peter

    2014-01-01

    Despite the fact that studies on self-determination theory have traditionally disregarded the explicit role of emotions in the motivation eliciting process, research attention for the affective antecedents of motivation is growing. We add to this emerging research field by testing the moderating role of emotion differentiation –individual differences in the extent to which people can differentiate between specific emotions– on the relationship between twelve specific emotions and intrinsic motivation. To this end, we conducted a daily diary study (N = 72) and an experience sampling study (N = 34). Results showed that the relationship between enthusiasm, cheerfulness, optimism, contentedness, gloominess, miserableness, uneasiness (in both studies 1 and 2), calmness, relaxation, tenseness, depression, worry (only in Study 1) on one hand and intrinsic motivation on the other hand was moderated by positive emotion differentiation for the positive emotions and by negative emotion differentiation for the negative emotions. Altogether, these findings suggest that for people who are unable to distinguish between different specific positive emotions the relationship between those specific positive emotions and intrinsic motivation is stronger, whereas the relationship between specific negative emotions and intrinsic motivation is weaker for people who are able to distinguish between the different specific negative emotions. Theoretical and practical implications are discussed. PMID:25517984

  19. Relating specific emotions to intrinsic motivation: on the moderating role of positive and negative emotion differentiation.

    Directory of Open Access Journals (Sweden)

    Leen Vandercammen

    Full Text Available Despite the fact that studies on self-determination theory have traditionally disregarded the explicit role of emotions in the motivation eliciting process, research attention for the affective antecedents of motivation is growing. We add to this emerging research field by testing the moderating role of emotion differentiation -individual differences in the extent to which people can differentiate between specific emotions- on the relationship between twelve specific emotions and intrinsic motivation. To this end, we conducted a daily diary study (N = 72 and an experience sampling study (N = 34. Results showed that the relationship between enthusiasm, cheerfulness, optimism, contentedness, gloominess, miserableness, uneasiness (in both studies 1 and 2, calmness, relaxation, tenseness, depression, worry (only in Study 1 on one hand and intrinsic motivation on the other hand was moderated by positive emotion differentiation for the positive emotions and by negative emotion differentiation for the negative emotions. Altogether, these findings suggest that for people who are unable to distinguish between different specific positive emotions the relationship between those specific positive emotions and intrinsic motivation is stronger, whereas the relationship between specific negative emotions and intrinsic motivation is weaker for people who are able to distinguish between the different specific negative emotions. Theoretical and practical implications are discussed.

  20. Emotional Gaming

    OpenAIRE

    Madeira, Filipa; Arriaga, Patrícia; Adrião, Joana; Lopes, Ricardo; Esteves, Francisco

    2013-01-01

    In recent years, research on the psychology of gaming has examined the negative and positive outcomes of playing video games. Thus far, a variety of affective phenomena have been investigated. In this chapter we will continue this exploration by examining the emotions elicited by the act of playing video games. Because the study of emotions must rely on different type of methods, including subjective self-reports (e.g., description of feelings), neuropsychophysiological measurements ...

  1. Expert model of decision-making system for efficient orientation of basketball players to positions and roles in the game--empirical verification.

    Science.gov (United States)

    Dezman, B; Trninić, S; Dizdar, D

    2001-06-01

    The purpose of the research was to empirically verify the expert model system designed for more efficient orientation of basketball players to particular positions and /or roles in the game (specialization). Participants were 60 randomly chosen male basketball players (12 players per each position) from the 12 Croatian 1st league teams in season 1998/99. Data were gathered from 10 basketball coaches who estimated overall performance (actual quality) of players on defense (7 variables) and on offense (12 variables). Variables were established by Trninić, Perica and Dizdar. A measure of body height was added to the aforementioned group of variables. The results obtained suggest that the proposed decision-making system can be used as an auxiliary instrument in orienting players to the positions and roles in the game. It has been established that the players have attained the highest grades of overall performance exactly at their primary playing positions in the game. The largest differences were determined between point guards (position 1) and centers (position 5). The greatest difficulties have occurred in determining optimal position for small forwards (position 3), then for shooting guards (position 2) and, last, for power forwards (position 4), because all these basketball players are the most versatile ones. Therefore, reliability of the system is the lowest when it is applied for selecting and orientating players to these positions. Convenient body height significantly contributes to aptitude of these players to play multiple positions and to assume multiple roles in the game. This research has reinforced the thesis that body height is a variable with the greatest influence on orientation of players to particular positions and roles in the game.

  2. BMP-2 Induced Expression of Alx3 That Is a Positive Regulator of Osteoblast Differentiation.

    Directory of Open Access Journals (Sweden)

    Takashi Matsumoto

    Full Text Available Bone morphogenetic proteins (BMPs regulate many aspects of skeletal development, including osteoblast and chondrocyte differentiation, cartilage and bone formation, and cranial and limb development. Among them, BMP-2, one of the most potent osteogenic signaling molecules, stimulates osteoblast differentiation, while it inhibits myogenic differentiation in C2C12 cells. To evaluate genes involved in BMP-2-induced osteoblast differentiation, we performed cDNA microarray analyses to compare BMP-2-treated and -untreated C2C12 cells. We focused on Alx3 (aristaless-like homeobox 3 which was clearly induced during osteoblast differentiation. Alx3, a homeobox gene related to the Drosophilaaristaless gene, has been linked to developmental functions in craniofacial structures and limb development. However, little is known about its direct relationship with bone formation. In the present study, we focused on the mechanisms of Alx3 gene expression and function during osteoblast differentiation induced by BMP-2. In C2C12 cells, BMP-2 induced increase of Alx3 gene expression in both time- and dose-dependent manners through the BMP receptors-mediated SMAD signaling pathway. In addition, silencing of Alx3 by siRNA inhibited osteoblast differentiation induced by BMP-2, as showed by the expressions of alkaline phosphatase (Alp, Osteocalcin, and Osterix, while over-expression of Alx3 enhanced osteoblast differentiation induced by BMP-2. These results indicate that Alx3 expression is enhanced by BMP-2 via the BMP receptors mediated-Smad signaling and that Alx3 is a positive regulator of osteoblast differentiation induced by BMP-2.

  3. Necessary and Sufficient Conditions for Pareto Optimality in Infinite Horizon Cooperative Differential Games - Replaced by CentER DP 2011-041

    NARCIS (Netherlands)

    Reddy, P.V.; Engwerda, J.C.

    2010-01-01

    In this article we derive necessary and sufficient conditions for the existence of Pareto optimal solutions for an N player cooperative infinite horizon differential game. Firstly, we write the problem of finding Pareto candidates as solving N constrained optimal control subproblems. We derive some

  4. Some Theoretical Aspects of Nonzero Sum Differential Games and Applications to Combat Problems

    Science.gov (United States)

    1971-06-01

    the Equilibrium Solution . 7 Hamilton-Jacobi-Bellman Partial Differential Equations ............. .............. 9 Influence Function Differential...Linearly .......... ............ 18 Problem Statement .......... ............ 18 Formulation of LJB Equations, Influence Function Equations and the TPBVP...19 Control Lawe . . .. ...... ........... 21 Conditions for Influence Function Continuity along Singular Surfaces

  5. Expression of POEM, a positive regulator of osteoblast differentiation, is suppressed by TNF-α

    International Nuclear Information System (INIS)

    Tsukasaki, Masayuki; Yamada, Atsushi; Suzuki, Dai; Aizawa, Ryo; Miyazono, Agasa; Miyamoto, Yoichi; Suzawa, Tetsuo; Takami, Masamichi; Yoshimura, Kentaro; Morimura, Naoko; Yamamoto, Matsuo; Kamijo, Ryutaro

    2011-01-01

    Highlights: → TNF-α inhibits POEM gene expression. → Inhibition of POEM gene expression is caused by NF-κB activation by TNF-α. → Over-expression of POEM recovers inhibition of osteoblast differentiation by TNF-α. -- Abstract: POEM, also known as nephronectin, is an extracellular matrix protein considered to be a positive regulator of osteoblast differentiation. In the present study, we found that tumor necrosis factor-α (TNF-α), a key regulator of bone matrix properties and composition that also inhibits terminal osteoblast differentiation, strongly inhibited POEM expression in the mouse osteoblastic cell line MC3T3-E1. TNF-α-induced down-regulation of POEM gene expression occurred in both time- and dose-dependent manners through the nuclear factor kappa B (NF-κB) pathway. In addition, expressions of marker genes in differentiated osteoblasts were down-regulated by TNF-α in a manner consistent with our findings for POEM, while over-expression of POEM recovered TNF-α-induced inhibition of osteoblast differentiation. These results suggest that TNF-α inhibits POEM expression through the NF-κB signaling pathway and down-regulation of POEM influences the inhibition of osteoblast differentiation by TNF-α.

  6. Expression of POEM, a positive regulator of osteoblast differentiation, is suppressed by TNF-{alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Tsukasaki, Masayuki [Department of Biochemistry, School of Dentistry, Showa University, 1-5-8 Hatanodai, Shinagawa, Tokyo 142-8555 (Japan); Yamada, Atsushi, E-mail: yamadaa@dent.showa-u.ac.jp [Department of Biochemistry, School of Dentistry, Showa University, 1-5-8 Hatanodai, Shinagawa, Tokyo 142-8555 (Japan); Suzuki, Dai [Department of Biochemistry, School of Dentistry, Showa University, 1-5-8 Hatanodai, Shinagawa, Tokyo 142-8555 (Japan); Aizawa, Ryo [Department of Biochemistry, School of Dentistry, Showa University, 1-5-8 Hatanodai, Shinagawa, Tokyo 142-8555 (Japan); Department of Periodontology, School of Dentistry, Showa University, 2-1-1 Kitasenzoku, Ohta, Tokyo 145-8515 (Japan); Miyazono, Agasa [Department of Periodontology, School of Dentistry, Showa University, 2-1-1 Kitasenzoku, Ohta, Tokyo 145-8515 (Japan); Miyamoto, Yoichi; Suzawa, Tetsuo; Takami, Masamichi; Yoshimura, Kentaro [Department of Biochemistry, School of Dentistry, Showa University, 1-5-8 Hatanodai, Shinagawa, Tokyo 142-8555 (Japan); Morimura, Naoko [Laboratory for Comparative Neurogenesis, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako-shi, Saitama 351-0198 (Japan); Yamamoto, Matsuo [Department of Periodontology, School of Dentistry, Showa University, 2-1-1 Kitasenzoku, Ohta, Tokyo 145-8515 (Japan); Kamijo, Ryutaro [Department of Biochemistry, School of Dentistry, Showa University, 1-5-8 Hatanodai, Shinagawa, Tokyo 142-8555 (Japan)

    2011-07-15

    Highlights: {yields} TNF-{alpha} inhibits POEM gene expression. {yields} Inhibition of POEM gene expression is caused by NF-{kappa}B activation by TNF-{alpha}. {yields} Over-expression of POEM recovers inhibition of osteoblast differentiation by TNF-{alpha}. -- Abstract: POEM, also known as nephronectin, is an extracellular matrix protein considered to be a positive regulator of osteoblast differentiation. In the present study, we found that tumor necrosis factor-{alpha} (TNF-{alpha}), a key regulator of bone matrix properties and composition that also inhibits terminal osteoblast differentiation, strongly inhibited POEM expression in the mouse osteoblastic cell line MC3T3-E1. TNF-{alpha}-induced down-regulation of POEM gene expression occurred in both time- and dose-dependent manners through the nuclear factor kappa B (NF-{kappa}B) pathway. In addition, expressions of marker genes in differentiated osteoblasts were down-regulated by TNF-{alpha} in a manner consistent with our findings for POEM, while over-expression of POEM recovered TNF-{alpha}-induced inhibition of osteoblast differentiation. These results suggest that TNF-{alpha} inhibits POEM expression through the NF-{kappa}B signaling pathway and down-regulation of POEM influences the inhibition of osteoblast differentiation by TNF-{alpha}.

  7. Markers to differentiate between Kaposi's sarcoma and tuberculous pleural effusions in HIV-positive patients.

    Science.gov (United States)

    Coleman, M; Finney, L J; Komrower, D; Chitani, A; Bates, J; Chipungu, G A; Corbett, E; Allain, T J

    2015-02-01

    Kaposi's sarcoma (KS) and tuberculosis (TB) commonly cause pleural effusions in high human immunodeficiency virus (HIV) burden resource-limited countries. Differentiating between them is challenging, as pleural biopsy and TB culture are rarely available. To identify markers to differentiate between TB effusions and KS effusions in HIV-positive patients, and to compare liquid culture and Xpert MTB/RIF in pleural fluid. Fifty HIV-positive patients with pleural effusions recruited in Malawi underwent pleural ultrasound and aspiration. Fluid visual inspection, cell count, bacterial culture, glucose/protein, solid and liquid TB culture and Xpert were performed. The mean age of the patients was 32 years; 30/50 (60%) were male and 29 (58%) had cutaneous/oral KS. Thirteen (26%) pleural fluid samples were liquid culture-positive for TB, while 9/13 (69%) were Xpert-positive. Three (10.3%) KS patients had culture-positive TB effusions; 17 (58.6%) had KS effusions. The relative risk of TB in KS patients increased with limited KS, loculated fluid and low glucose. Eleven (52.3%) non-KS patients had culture-positive TB effusions associated with male sex, straw-coloured fluid and fibrin stranding on ultrasound. KS patients were most likely to have KS effusion, but TB should be considered. Most non-KS patients had TB, supporting the use of World Health Organization guidelines. Xpert identified two thirds of liquid culture-positive results.

  8. Chemical networks with inflows and outflows: a positive linear differential inclusions approach.

    Science.gov (United States)

    Angeli, David; De Leenheer, Patrick; Sontag, Eduardo D

    2009-01-01

    Certain mass-action kinetics models of biochemical reaction networks, although described by nonlinear differential equations, may be partially viewed as state-dependent linear time-varying systems, which in turn may be modeled by convex compact valued positive linear differential inclusions. A result is provided on asymptotic stability of such inclusions, and applied to a ubiquitous biochemical reaction network with inflows and outflows, known as the futile cycle. We also provide a characterization of exponential stability of general homogeneous switched systems which is not only of interest in itself, but also plays a role in the analysis of the futile cycle. 2009 American Institute of Chemical Engineers

  9. Stackelberg equilibria and horizontal differentiation

    OpenAIRE

    Lambertini, Luca

    1993-01-01

    This paper proposes a taxonomy of the Stackelberg equilibria emerging from a standard game of horizontal differentiation à la Hotelling in which the strategy set of the sellers in the location stage is the real axis. Repeated leadership appears the most advantageous position. Furthermore, this endogenously yields vertical differentiation between products at equilibrium.

  10. Application of differential game theory to role-determination in aerial combat

    Science.gov (United States)

    Merz, A. W.

    1975-01-01

    The development of criteria which specify the roles of pursuer and evader as functions of the relative geometry and of the important parameters of the problem are discussed. A reduced-order model of the relative motion is derived and discussed. In this model, the two aircraft move in the same plane at unequal but constant speeds, and with different maximum turn rates. The equations of relative motion are of third order, the dependent variables being the relative range, bearing, and heading of the two aircraft. Termination of the pursuit-evasion game is defined by either the heading-limited or the range-limited end condition. These are geometric conditions for which the evading aircraft is in front of the other, with the relative heading and relative range satisfying certain inequalities. Retrograde solutions to the equations of relative motion were used with the derived optimal terminal maneuvers to find where an assumed set of end conditions could have begun.

  11. Model-Free Adaptive Control for Unknown Nonlinear Zero-Sum Differential Game.

    Science.gov (United States)

    Zhong, Xiangnan; He, Haibo; Wang, Ding; Ni, Zhen

    2018-05-01

    In this paper, we present a new model-free globalized dual heuristic dynamic programming (GDHP) approach for the discrete-time nonlinear zero-sum game problems. First, the online learning algorithm is proposed based on the GDHP method to solve the Hamilton-Jacobi-Isaacs equation associated with optimal regulation control problem. By setting backward one step of the definition of performance index, the requirement of system dynamics, or an identifier is relaxed in the proposed method. Then, three neural networks are established to approximate the optimal saddle point feedback control law, the disturbance law, and the performance index, respectively. The explicit updating rules for these three neural networks are provided based on the data generated during the online learning along the system trajectories. The stability analysis in terms of the neural network approximation errors is discussed based on the Lyapunov approach. Finally, two simulation examples are provided to show the effectiveness of the proposed method.

  12. Parallel arrangements of positive feedback loops limit cell-to-cell variability in differentiation.

    Directory of Open Access Journals (Sweden)

    Anupam Dey

    Full Text Available Cellular differentiations are often regulated by bistable switches resulting from specific arrangements of multiple positive feedback loops (PFL fused to one another. Although bistability generates digital responses at the cellular level, stochasticity in chemical reactions causes population heterogeneity in terms of its differentiated states. We hypothesized that the specific arrangements of PFLs may have evolved to minimize the cellular heterogeneity in differentiation. In order to test this we investigated variability in cellular differentiation controlled either by parallel or serial arrangements of multiple PFLs having similar average properties under extrinsic and intrinsic noises. We find that motifs with PFLs fused in parallel to one another around a central regulator are less susceptible to noise as compared to the motifs with PFLs arranged serially. Our calculations suggest that the increased resistance to noise in parallel motifs originate from the less sensitivity of bifurcation points to the extrinsic noise. Whereas estimation of mean residence times indicate that stable branches of bifurcations are robust to intrinsic noise in parallel motifs as compared to serial motifs. Model conclusions are consistent both in AND- and OR-gate input signal configurations and also with two different modeling strategies. Our investigations provide some insight into recent findings that differentiation of preadipocyte to mature adipocyte is controlled by network of parallel PFLs.

  13. Parallel arrangements of positive feedback loops limit cell-to-cell variability in differentiation.

    Science.gov (United States)

    Dey, Anupam; Barik, Debashis

    2017-01-01

    Cellular differentiations are often regulated by bistable switches resulting from specific arrangements of multiple positive feedback loops (PFL) fused to one another. Although bistability generates digital responses at the cellular level, stochasticity in chemical reactions causes population heterogeneity in terms of its differentiated states. We hypothesized that the specific arrangements of PFLs may have evolved to minimize the cellular heterogeneity in differentiation. In order to test this we investigated variability in cellular differentiation controlled either by parallel or serial arrangements of multiple PFLs having similar average properties under extrinsic and intrinsic noises. We find that motifs with PFLs fused in parallel to one another around a central regulator are less susceptible to noise as compared to the motifs with PFLs arranged serially. Our calculations suggest that the increased resistance to noise in parallel motifs originate from the less sensitivity of bifurcation points to the extrinsic noise. Whereas estimation of mean residence times indicate that stable branches of bifurcations are robust to intrinsic noise in parallel motifs as compared to serial motifs. Model conclusions are consistent both in AND- and OR-gate input signal configurations and also with two different modeling strategies. Our investigations provide some insight into recent findings that differentiation of preadipocyte to mature adipocyte is controlled by network of parallel PFLs.

  14. Clinical characteristics differentiating bacteriologically positive pulmonary tuberculosis patients from negative ones in Mongolia.

    Science.gov (United States)

    Toyota, M; Yasuda, N; Koda, S; Ohara, H; Enkhbat, S; Tsogt, G

    1998-06-01

    The objective of this study is to clarify clinical characteristics which differentiate bacteriologically positive pulmonary tuberculosis patients from negative ones in Mongolia. The subjects include 338 patients aged 16 years and older who had undergone bacteriological examinations. Of them, 107 patients (31.7%) were confirmed bacteriologically. The proportion of bacteriological positive results increased significantly among patients who had cavities in the roentgenographic examination, cough at diagnosis and the family history of tuberculosis. Addressing these clinical characteristics will contribute to raising not only the sensitivity of the sputum examination, but also the specificity of the roentgenographic examination in the diagnostic process of tuberculosis.

  15. The linear variable differential transformer (LVDT) position sensor for gravitational wave interferometer low-frequency controls

    Energy Technology Data Exchange (ETDEWEB)

    Tariq, Hareem E-mail: htariq@ligo.caltech.edu; Takamori, Akiteru; Vetrano, Flavio; Wang Chenyang; Bertolini, Alessandro; Calamai, Giovanni; DeSalvo, Riccardo; Gennai, Alberto; Holloway, Lee; Losurdo, Giovanni; Marka, Szabolcs; Mazzoni, Massimo; Paoletti, Federico; Passuello, Diego; Sannibale, Virginio; Stanga, Ruggero

    2002-08-21

    Low-power, ultra-high-vacuum compatible, non-contacting position sensors with nanometer resolution and centimeter dynamic range have been developed, built and tested. They have been designed at Virgo as the sensors for low-frequency modal damping of Seismic Attenuation System chains in Gravitational Wave interferometers and sub-micron absolute mirror positioning. One type of these linear variable differential transformers (LVDTs) has been designed to be also insensitive to transversal displacement thus allowing 3D movement of the sensor head while still precisely reading its position along the sensitivity axis. A second LVDT geometry has been designed to measure the displacement of the vertical seismic attenuation filters from their nominal position. Unlike the commercial LVDTs, mostly based on magnetic cores, the LVDTs described here exert no force on the measured structure.

  16. A computational proof of concept of a machine-intelligent artificial pancreas using Lyapunov stability and differential game theory.

    Science.gov (United States)

    Greenwood, Nigel J C; Gunton, Jenny E

    2014-07-01

    This study demonstrated the novel application of a "machine-intelligent" mathematical structure, combining differential game theory and Lyapunov-based control theory, to the artificial pancreas to handle dynamic uncertainties. Realistic type 1 diabetes (T1D) models from the literature were combined into a composite system. Using a mixture of "black box" simulations and actual data from diabetic medical histories, realistic sets of diabetic time series were constructed for blood glucose (BG), interstitial fluid glucose, infused insulin, meal estimates, and sometimes plasma insulin assays. The problem of underdetermined parameters was side stepped by applying a variant of a genetic algorithm to partial information, whereby multiple candidate-personalized models were constructed and then rigorously tested using further data. These formed a "dynamic envelope" of trajectories in state space, where each trajectory was generated by a hypothesis on the hidden T1D system dynamics. This dynamic envelope was then culled to a reduced form to cover observed dynamic behavior. A machine-intelligent autonomous algorithm then implemented game theory to construct real-time insulin infusion strategies, based on the flow of these trajectories through state space and their interactions with hypoglycemic or near-hyperglycemic states. This technique was tested on 2 simulated participants over a total of fifty-five 24-hour days, with no hypoglycemic or hyperglycemic events, despite significant uncertainties from using actual diabetic meal histories with 10-minute warnings. In the main case studies, BG was steered within the desired target set for 99.8% of a 16-hour daily assessment period. Tests confirmed algorithm robustness for ±25% carbohydrate error. For over 99% of the overall 55-day simulation period, either formal controller stability was achieved to the desired target or else the trajectory was within the desired target. These results suggest that this is a stable, high

  17. Mathematical games, abstract games

    CERN Document Server

    Neto, Joao Pedro

    2013-01-01

    User-friendly, visually appealing collection offers both new and classic strategic board games. Includes abstract games for two and three players and mathematical games such as Nim and games on graphs.

  18. COMBINING THE CONCEPTS OF BENCHMARKING AND MATRIX GAME IN MARKETING (RE)POSITIONING OF SEAPORTS

    OpenAIRE

    Senka Sekularac-Ivošević; Sanja Bauk; Mirjana Gligorijević

    2013-01-01

    This paper considers the effects of combination of two different approaches in developing seaports positioning strategy. The first one is based on comparing the most important quantitative and qualitative seaports choice criteria by benchmarking method. Benchmarking has been used in creating the appropriate model for efficient marketing positioning of Aegean, Adriatic and Black Sea seaports. The criteria that describe the degree of these seaports competitiveness are chosen upon the investigat...

  19. Variability of Characteristics Physiologic and Anthropometric in Practitioners of Rugby in Function of the Category and Position of Game: Systematic revision of Literature

    Directory of Open Access Journals (Sweden)

    F.M. Campos

    2008-01-01

    Full Text Available Objectives: Analyse the existence variability of anthropometric and physiologic characteristics in Rugby players according their game position and competitive level. Methodology: enhances the existence of significant variability in matter of different evaluation parameters subordinated to two ranges of characteristics anthropometric (weight, height, % of body mass and age and physiologic (muscular power, maximum aerobic power, speed according the practice status (professionals, semi-professional, amateur and the position in game (forwards, backs. Results: they point with respect to clear differences the anthropometric and physiological level profile of the players, particularly when related to the competitive level. The level half-professional verifies a significant effect of the age in the corporal mass, muscular force, speed, agility and maximum aerobic capacity, with the physiological characteristics of the players to verify an increase in function of the increase of the game level. Conclusions: the results gotten in the different studies for amateur players do not demonstrate linearity what if it must in particular the games with low intensity, with frequency and regularity irregular, of short duration or based in training programs little structuralized or inappropriate. Parameters related with the agility, speed, muscular force and VO2máx present a gradual development in function of the increase of the age and the level the one that the game is practiced. On the other hand, in terms of the position assumed for the player in field, the physiological profile of professional players is similar wants if it deals with advanced wants well of defenses if that the anthropometric variations are in this field particularly well-known. In anthropometrics terms, the practitioners of Rugby present high muscular mass, being the players in the position of advanced older and more weighed than the defenses. Parallel he exists a significant effect of the age

  20. Differential barometric-based positioning technique for indoor elevation measurement in IoT medical applications.

    Science.gov (United States)

    Wang, Hua; Wen, Yingyou; Zhao, Dazhe

    2017-07-20

    Medical applications have begun to benefit from Internet of Things (IoT) technology through the introduction of wearable devices. Several medical applications require accurate patient location as various changes affect pressure parameters inside the body. This study aims to develop a system to measure indoor altitude for IoT medical applications. We propose a differential barometric-based positioning system to estimate the altitude between a reference sensor and a localizing sensor connected to the human body. The differential barometric altimetry model is introduced to estimate indoor elevations and eliminate environmental artifacts. In addition, a Gaussian filter processing is adopted to remove noise from the elevation measurements. The proposed system is then investigated through extensive experiments, using various evaluation criteria. The results indicate that the proposed system yielded good accuracy with reduced implementation complexity and fewer costs. The proposed system is resilient compared to other indoor localization approaches, even when numerous environmental artifacts in indoor environments are present.

  1. Existence of Positive Solutions to a Boundary Value Problem for a Delayed Nonlinear Fractional Differential System

    Directory of Open Access Journals (Sweden)

    Chen Yuming

    2011-01-01

    Full Text Available Though boundary value problems for fractional differential equations have been extensively studied, most of the studies focus on scalar equations and the fractional order between 1 and 2. On the other hand, delay is natural in practical systems. However, not much has been done for fractional differential equations with delays. Therefore, in this paper, we consider a boundary value problem of a general delayed nonlinear fractional system. With the help of some fixed point theorems and the properties of the Green function, we establish several sets of sufficient conditions on the existence of positive solutions. The obtained results extend and include some existing ones and are illustrated with some examples for their feasibility.

  2. Game Performance Evaluation in Male Goalball Players

    Science.gov (United States)

    Molik, Bartosz; Morgulec-Adamowicz, Natalia; Kosmol, Andrzej; Perkowski, Krzysztof; Bednarczuk, Grzegorz; Skowroński, Waldemar; Gomez, Miguel Angel; Koc, Krzysztof; Rutkowska, Izabela; Szyman, Robert J

    2015-01-01

    Goalball is a Paralympic sport exclusively for athletes who are visually impaired and blind. The aims of this study were twofold: to describe game performance of elite male goalball players based upon the degree of visual impairment, and to determine if game performance was related to anthropometric characteristics of elite male goalball players. The study sample consisted of 44 male goalball athletes. A total of 38 games were recorded during the Summer Paralympic Games in London 2012. Observations were reported using the Game Efficiency Sheet for Goalball. Additional anthropometric measurements included body mass (kg), body height (cm), the arm span (cm) and length of the body in the defensive position (cm). The results differentiating both groups showed that the players with total blindness obtained higher means than the players with visual impairment for game indicators such as the sum of defense (p = 0.03) and the sum of good defense (p = 0.04). The players with visual impairment obtained higher results than those with total blindness for attack efficiency (p = 0.04), the sum of penalty defenses (p = 0.01), and fouls (p = 0.01). The study showed that athletes with blindness demonstrated higher game performance in defence. However, athletes with visual impairment presented higher efficiency in offensive actions. The analyses confirmed that body mass, body height, the arm span and length of the body in the defensive position did not differentiate players’ performance at the elite level. PMID:26834872

  3. Game Performance Evaluation in Male Goalball Players

    Directory of Open Access Journals (Sweden)

    Molik Bartosz

    2015-12-01

    Full Text Available Goalball is a Paralympic sport exclusively for athletes who are visually impaired and blind. The aims of this study were twofold: to describe game performance of elite male goalball players based upon the degree of visual impairment, and to determine if game performance was related to anthropometric characteristics of elite male goalball players. The study sample consisted of 44 male goalball athletes. A total of 38 games were recorded during the Summer Paralympic Games in London 2012. Observations were reported using the Game Efficiency Sheet for Goalball. Additional anthropometric measurements included body mass (kg, body height (cm, the arm span (cm and length of the body in the defensive position (cm. The results differentiating both groups showed that the players with total blindness obtained higher means than the players with visual impairment for game indicators such as the sum of defense (p = 0.03 and the sum of good defense (p = 0.04. The players with visual impairment obtained higher results than those with total blindness for attack efficiency (p = 0.04, the sum of penalty defenses (p = 0.01, and fouls (p = 0.01. The study showed that athletes with blindness demonstrated higher game performance in defence. However, athletes with visual impairment presented higher efficiency in offensive actions. The analyses confirmed that body mass, body height, the arm span and length of the body in the defensive position did not differentiate players’ performance at the elite level.

  4. Analysis of RDSS positioning accuracy based on RNSS wide area differential technique

    Science.gov (United States)

    Xing, Nan; Su, RanRan; Zhou, JianHua; Hu, XiaoGong; Gong, XiuQiang; Liu, Li; He, Feng; Guo, Rui; Ren, Hui; Hu, GuangMing; Zhang, Lei

    2013-10-01

    The BeiDou Navigation Satellite System (BDS) provides Radio Navigation Service System (RNSS) as well as Radio Determination Service System (RDSS). RDSS users can obtain positioning by responding the Master Control Center (MCC) inquiries to signal transmitted via GEO satellite transponder. The positioning result can be calculated with elevation constraint by MCC. The primary error sources affecting the RDSS positioning accuracy are the RDSS signal transceiver delay, atmospheric trans-mission delay and GEO satellite position error. During GEO orbit maneuver, poor orbit forecast accuracy significantly impacts RDSS services. A real-time 3-D orbital correction method based on wide-area differential technique is raised to correct the orbital error. Results from the observation shows that the method can successfully improve positioning precision during orbital maneuver, independent from the RDSS reference station. This improvement can reach 50% in maximum. Accurate calibration of the RDSS signal transceiver delay precision and digital elevation map may have a critical role in high precise RDSS positioning services.

  5. Attention deficit/hyperactivity disorder blame game: a study on the positioning of professionals, teachers and parents.

    Science.gov (United States)

    Frigerio, Alessandra; Montali, Lorenzo; Fine, Michelle

    2013-11-01

    Attention deficit/hyperactivity disorder is currently the most debated childhood psychiatric diagnosis. Given the circulation of competing perspectives about the 'real' causes of children's behaviour and the 'best' way to treat them, we aim to analyse the interactions of the central social actors' discourses about attention deficit/hyperactivity disorder children within the Italian context. Adopting a multi-method approach, we focus on the polyphonic chorus of voices surrounding the child, studying the discourses of mental health professionals, teachers and parents. These actors are representative of three contexts that are deeply engaged with attention deficit/hyperactivity disorder: medical institutions, schools and families. Our theoretical and methodological approach integrates positioning theory, the Bakhtinian notion of dialogical thinking and discourse analysis to study stakeholders' reflexive and interactive positioning in terms of the attribution of rights, duties, responsibilities and power issues. The results show that mutual blame is a constitutive element of relational dynamics among the key adults surrounding attention deficit/hyperactivity disorder children. We argue that these conflicting relationships are not merely related to the debate regarding the validity of the attention deficit/hyperactivity disorder diagnosis. Rather, the mutual blame centres on questions of compliance, recognition of authority and morality. Through the blame game, adults negotiate their own and others' subjectivity in ways that simultaneously (re)produce power relationships and resistance efforts.

  6. Multi-objective trajectory optimization of Space Manoeuvre Vehicle using adaptive differential evolution and modified game theory

    Science.gov (United States)

    Chai, Runqi; Savvaris, Al; Tsourdos, Antonios; Chai, Senchun

    2017-07-01

    Highly constrained trajectory optimization for Space Manoeuvre Vehicles (SMV) is a challenging problem. In practice, this problem becomes more difficult when multiple mission requirements are taken into account. Because of the nonlinearity in the dynamic model and even the objectives, it is usually hard for designers to generate a compromised trajectory without violating strict path and box constraints. In this paper, a new multi-objective SMV optimal control model is formulated and parameterized using combined shooting-collocation technique. A modified game theory approach, coupled with an adaptive differential evolution algorithm, is designed in order to generate the pareto front of the multi-objective trajectory optimization problem. In addition, to improve the quality of obtained solutions, a control logic is embedded in the framework of the proposed approach. Several existing multi-objective evolutionary algorithms are studied and compared with the proposed method. Simulation results indicate that without driving the solution out of the feasible region, the proposed method can perform better in terms of convergence ability and convergence speed than its counterparts. Moreover, the quality of the pareto set generated using the proposed method is higher than other multi-objective evolutionary algorithms, which means the newly proposed algorithm is more attractive for solving multi-criteria SMV trajectory planning problem.

  7. Existence of positive solutions for boundary value problems of fractional functional differential equations

    Directory of Open Access Journals (Sweden)

    Chuanzhi Bai

    2010-06-01

    Full Text Available This paper deals with the existence of positive solutions for a boundary value problem involving a nonlinear functional differential equation of fractional order $\\alpha$ given by $ D^{\\alpha} u(t + f(t, u_t = 0$, $t \\in (0, 1$, $2 < \\alpha \\le 3$, $ u^{\\prime}(0 = 0$, $u^{\\prime}(1 = b u^{\\prime}(\\eta$, $u_0 = \\phi$. Our results are based on the nonlinear alternative of Leray-Schauder type and Krasnosel'skii fixed point theorem.

  8. De-novo discovery of differentially abundant transcription factor binding sites including their positional preference.

    Science.gov (United States)

    Keilwagen, Jens; Grau, Jan; Paponov, Ivan A; Posch, Stefan; Strickert, Marc; Grosse, Ivo

    2011-02-10

    Transcription factors are a main component of gene regulation as they activate or repress gene expression by binding to specific binding sites in promoters. The de-novo discovery of transcription factor binding sites in target regions obtained by wet-lab experiments is a challenging problem in computational biology, which has not been fully solved yet. Here, we present a de-novo motif discovery tool called Dispom for finding differentially abundant transcription factor binding sites that models existing positional preferences of binding sites and adjusts the length of the motif in the learning process. Evaluating Dispom, we find that its prediction performance is superior to existing tools for de-novo motif discovery for 18 benchmark data sets with planted binding sites, and for a metazoan compendium based on experimental data from micro-array, ChIP-chip, ChIP-DSL, and DamID as well as Gene Ontology data. Finally, we apply Dispom to find binding sites differentially abundant in promoters of auxin-responsive genes extracted from Arabidopsis thaliana microarray data, and we find a motif that can be interpreted as a refined auxin responsive element predominately positioned in the 250-bp region upstream of the transcription start site. Using an independent data set of auxin-responsive genes, we find in genome-wide predictions that the refined motif is more specific for auxin-responsive genes than the canonical auxin-responsive element. In general, Dispom can be used to find differentially abundant motifs in sequences of any origin. However, the positional distribution learned by Dispom is especially beneficial if all sequences are aligned to some anchor point like the transcription start site in case of promoter sequences. We demonstrate that the combination of searching for differentially abundant motifs and inferring a position distribution from the data is beneficial for de-novo motif discovery. Hence, we make the tool freely available as a component of the open

  9. Positive periodic solutions of neutral functional differential equations with a parameter and impulse

    Directory of Open Access Journals (Sweden)

    Xuanlong Fan

    2008-03-01

    Full Text Available In this paper, we consider first-order neutral differential equations with a parameter and impulse in the form of $$displaylines{ frac{d}{dt}[x(t-c x(t-gamma]=-a(tg(x(h_1(tx(t+lambda b(t fig(x(h_2(tig,quad t eq t_j;cr Delta ig[x(t-c x(t-gammaig]=I_jig(x(tig,quad t=t_j,; jinmathbb{Z}^+. }$$ Leggett-Williams fixed point theorem, we prove the existence of three positive periodic solutions.

  10. Positive schizotypy and negative schizotypy are associated with differential patterns of episodic memory impairment

    Directory of Open Access Journals (Sweden)

    Lili Sahakyan

    2016-09-01

    Full Text Available Cognitive impairment is a hallmark of schizophrenia; however, studies have not comprehensively examined such impairments in non-clinically ascertained schizotypic young adults. The present study employed a series of measures to assess episodic memory in high positive schizotypy, high negative schizotypy, and comparison groups (each group n = 25. Consistent with diminished cognitive functioning seen in negative symptom schizophrenia, the negative schizotypy group exhibited deficits on free recall, recognition, and source memory tasks. The positive schizotypy group did not demonstrate deficits on the above mentioned tasks. However, in contrast to the other groups, the positive schizotypy group showed an unexpected set-size effect on the cued-recall task. Set-size effect, which refers to the finding that words that have smaller networks of associates tend to have a memory advantage, is usually found in associative-cuing, but not cued-recall, tasks. The finding for the positive schizotypy group is consistent with heightened spreading activation and reduced executive control suggested to underlie psychotic symptoms. The findings support a multidimensional model of schizotypy and schizophrenia, and suggest that positive and negative schizotypy involve differential patterns of cognitive impairment.

  11. Research on channel characteristics of differential multi pulse position modulation without background noise

    Science.gov (United States)

    Gao, Zhuo; Zhan, Weida; Sun, Quan; Hao, Ziqiang

    2018-04-01

    Differential multi-pulse position modulation (DMPPM) is a new type of modulation technology. There is a fast transmission rate, high bandwidth utilization, high modulation rate characteristics. The study of DMPPM modulation has important scientific value and practical significance. Channel capacity is one of the important indexes to measure the communication capability of communication system, and studying the channel capacity of DMPPM without background noise is the key to analyze the characteristics of DMPPM. The DMPPM theoretical model is established. The symbol structure of DMPPM with guard time slot is analyzed, and the channel capacity expression of DMPPM is deduced. Simulation analysis by MATLAB. The curves of unit channel capacity and capacity efficiency at different pulse and photon counting rates are analyzed. The results show that DMPPM is more advantageous than multi-pulse position modulation (MPPM), and is more suitable for future wireless optical communication system.

  12. Introduction to game theory

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The basic ideas of game theory were originated from the problems of maximum and minimum given by J.Yon Neumann in 1928. Later, wars accelerated the study of game theory, there are many developments that contributed to the advancement of game theory, many problems of optimum appeared in economic development process. Scientists applied mathematic methods to studying game theory to make the theory more profound and perfect. The axiomatic structure of game theory was nearly complete in 1944. The path of the development of game theory started from finite to infinite, from two players to many players, from expressing gains with quantity to showing the ending of game theory with abstract result, and from certainty problems to random problems. Thus development of game theory is closely related to the economic development. In recent years, the research on the non-differentiability of Shapley value posed by Belgian Mertens is one of the advanced studies in game theory.

  13. New hybrid reverse differential pulse position width modulation scheme for wireless optical communication

    Science.gov (United States)

    Liao, Renbo; Liu, Hongzhan; Qiao, Yaojun

    2014-05-01

    In order to improve the power efficiency and reduce the packet error rate of reverse differential pulse position modulation (RDPPM) for wireless optical communication (WOC), a hybrid reverse differential pulse position width modulation (RDPPWM) scheme is proposed, based on RDPPM and reverse pulse width modulation. Subsequently, the symbol structure of RDPPWM is briefly analyzed, and its performance is compared with that of other modulation schemes in terms of average transmitted power, bandwidth requirement, and packet error rate over ideal additive white Gaussian noise (AWGN) channels. Based on the given model, the simulation results show that the proposed modulation scheme has the advantages of improving the power efficiency and reducing the bandwidth requirement. Moreover, in terms of error probability performance, RDPPWM can achieve a much lower packet error rate than that of RDPPM. For example, at the same received signal power of -28 dBm, the packet error rate of RDPPWM can decrease to 2.6×10-12, while that of RDPPM is 2.2×10. Furthermore, RDPPWM does not need symbol synchronization at the receiving end. These considerations make RDPPWM a favorable candidate to select as the modulation scheme in the WOC systems.

  14. Ly49Q, an ITIM-bearing NK receptor, positively regulates osteoclast differentiation

    International Nuclear Information System (INIS)

    Hayashi, Mikihito; Nakashima, Tomoki; Kodama, Tatsuhiko; Makrigiannis, Andrew P.; Toyama-Sorimachi, Noriko; Takayanagi, Hiroshi

    2010-01-01

    Osteoclasts, multinucleated cells that resorb bone, play a key role in bone remodeling. Although immunoreceptor tyrosine-based activation motif (ITAM)-mediated signaling is critical for osteoclast differentiation, the significance of immunoreceptor tyrosine-based inhibitory motif (ITIM) has not been well understood. Here we report the function of Ly49Q, an Ly49 family member possessing an ITIM motif, in osteoclastogenesis. Ly49Q is selectively induced by receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL) stimulation in bone marrow-derived monocyte/macrophage precursor cells (BMMs) among the Ly49 family of NK receptors. The knockdown of Ly49Q resulted in a significant reduction in the RANKL-induced formation of tartrate-resistance acid phosphatase (TRAP)-positive multinucleated cells, accompanied by a decreased expression of osteoclast-specific genes such as Nfatc1, Tm7sf4, Oscar, Ctsk, and Acp5. Osteoclastogenesis was also significantly impaired in Ly49Q-deficient cells in vitro. The inhibitory effect of Ly49Q-deficiency may be explained by the finding that Ly49Q competed for the association of Src-homology domain-2 phosphatase-1 (SHP-1) with paired immunoglobulin-like receptor-B (PIR-B), an ITIM-bearing receptor which negatively regulates osteoclast differentiation. Unexpectedly, Ly49Q deficiency did not lead to impaired osteoclast formation in vivo, suggesting the existence of a compensatory mechanism. This study provides an example in which an ITIM-bearing receptor functions as a positive regulator of osteoclast differentiation.

  15. EXISTENCE OF POSITIVE SOLUTION TO TWO-POINT BOUNDARY VALUE PROBLEM FOR A SYSTEM OF SECOND ORDER ORDINARY DIFFERENTIAL EQUATIONS

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this paper, we consider a two-point boundary value problem for a system of second order ordinary differential equations. Under some conditions, we show the existence of positive solution to the system of second order ordinary differential equa-tions.

  16. Positive nondecreasing solutions for a multi-term fractional-order functional differential equation with integral conditions

    OpenAIRE

    Ahmed M. A. El-Sayed; Ebtisam O. Bin-Taher

    2011-01-01

    In this article, we prove the existence of positive nondecreasing solutions for a multi-term fractional-order functional differential equations. We consider Cauchy boundary problems with: nonlocal conditions, two-point boundary conditions, integral conditions, and deviated arguments.

  17. Evidence for differential control of tibial position in perturbed unilateral stance after acute ACL rupture.

    Science.gov (United States)

    Chmielewski, T L; Ramsey, D K; Snyder-Mackler, L

    2005-01-01

    Functional outcomes in anterior cruciate ligament-deficient "potential copers" and "non-copers" may be related to their knee stabilization strategies. Therefore, the purpose of this study was to differentiate dynamic knee stabilization strategies of potential copers and non-copers through analysis of sagittal plane knee angle and tibia position during disturbed and undisturbed unilateral standing. Ten uninjured potential coper and non-coper subjects stood in unilateral stance on a platform that translated anteriorly, posteriorly and laterally. Knee angle and tibia position with reference to the femur were calculated before and after platform movement. During perturbation trials, potential copers maintained kinematics that were similar to uninjured subjects across conditions. Conversely, non-copers stood with greater knee flexion than uninjured subjects and a tibia position that was more posterior than the other groups. Both non-copers and potential copers demonstrated small changes in tibia position following platform movement, but direction of movement was not similar. The similarities between the knee kinematics of potential copers and uninjured subjects suggest that potential copers compensated well from their injury by utilizing analogous dynamic knee stabilization strategies. In comparison to the other groups, by keeping the knee in greater flexion and the tibia in a more posterior position, non-copers appear to constrain the tibia in response to a challenging task, which is consistent with a "stiffening strategy". Based on the poor functional outcomes of non-copers, a stiffening strategy does not lead to dynamic knee stability, and the strategy may increase compressive forces which could contribute to or exacerbate articular cartilage degeneration.

  18. Implications of Thyroglobulin Antibody Positivity in Patients with Differentiated Thyroid Cancer

    DEFF Research Database (Denmark)

    Verburg, Frederik A; Luster, Markus; Cupini, Cristina

    2013-01-01

    Background: Even though the presence of antithyroglobulin antibodies (TgAbs) represents a significant problem in the follow-up of patients with differentiated thyroid cancer (DTC), the current guidelines on the management of DTC that have been published in recent years contain no text concerning...... the methods to be used for detecting such antibody-related interference in thyroglobulin (Tg) measurement or how to manage TgAb-positive patients in whom Tg cannot be used reliably as a tumor marker. Aim: An international group of experts from the European Thyroid Association Cancer Research Network who...... insufficient evidence was available, a thorough discussion by a group of physician-scientists, all of whom have a distinguished track record in thyroid cancer care, was held to arrive at a consensus expert opinion. The questions and answers discussed were then summarized into an algorithm for the management...

  19. The Positive Properties of Green’s Function for Fractional Differential Equations and Its Applications

    Directory of Open Access Journals (Sweden)

    Fuquan Jiang

    2013-01-01

    Full Text Available We consider the properties of Green’s function for the nonlinear fractional differential equation boundary value problem: D0+αu(t+f(t,u(t+e(t=0,0positive solutions for singular boundary value problems by means of Schauder fixed-point theorem.

  20. Positive Periodic Solution for the Generalized Neutral Differential Equation with Multiple Delays and Impulse

    Directory of Open Access Journals (Sweden)

    Zhenguo Luo

    2014-01-01

    Full Text Available By using a fixed point theorem of strict-set-contraction, which is different from Gaines and Mawhin's continuation theorem and abstract continuation theory for k-set contraction, we established some new criteria for the existence of positive periodic solution of the following generalized neutral delay functional differential equation with impulse: x'(t=x(t[a(t-f(t,x(t,x(t-τ1(t,x(t,…,x(t-τn(t,x(t,x'(t-γ1(t,x(t,…,x'(t-γm(t,x(t],  t≠tk,  k∈Z+;  x(tk+=x(tk-+θk(x(tk,  k∈Z+. As applications of our results, we also give some applications to several Lotka-Volterra models and new results are obtained.

  1. Differential effects of galvanic vestibular stimulation on arm position sense in right- vs. left-handers.

    Science.gov (United States)

    Schmidt, Lena; Artinger, Frank; Stumpf, Oliver; Kerkhoff, Georg

    2013-04-01

    The human brain is organized asymmetrically in two hemispheres with different functional specializations. Left- and right-handers differ in many functional capacities and their anatomical representations. Right-handers often show a stronger functional lateralization than left-handers, the latter showing a more bilateral, symmetrical brain organization. Recent functional imaging evidence shows a different lateralization of the cortical vestibular system towards the side of the preferred hand in left- vs. right-handers as well. Since the vestibular system is involved in somatosensory processing and the coding of body position, vestibular stimulation should affect such capacities differentially in left- vs. right-handers. In the present, sham-stimulation-controlled study we explored this hypothesis by studying the effects of galvanic vestibular stimulation (GVS) on proprioception in both forearms in left- and right-handers. Horizontal arm position sense (APS) was measured with an opto-electronic device. Second, the polarity-specific online- and after-effects of subsensory, bipolar GVS on APS were investigated in different sessions separately for both forearms. At baseline, both groups did not differ in their unsigned errors for both arms. However, right-handers showed significant directional errors in APS of both arms towards their own body. Right-cathodal/left-anodal GVS, resulting in right vestibular cortex activation, significantly deteriorated left APS in right-handers, but had no detectable effect on APS in left-handers in either arm. These findings are compatible with a right-hemisphere dominance for vestibular functions in right-handers and a differential vestibular organization in left-handers that compensates for the disturbing effects of GVS on APS. Moreover, our results show superior arm proprioception in left-handers in both forearms. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Helicopter approach capability using the differential global positioning system. M.S. Thesis

    Science.gov (United States)

    Kaufmann, David N.

    1993-01-01

    The results of flight tests to determine the feasibility of using the Global Positioning System (GPS) in the differential mode (DGPS) to provide high accuracy, precision navigation, and guidance for helicopter approaches to landing are presented. The airborne DGPS receiver and associated equipment is installed in a NASA UH-60 Black Hawk helicopter. The ground-based DGPS reference receiver is located at a surveyed test site and is equipped with a real-time VHF data link to transmit correction information to the airborne DGPS receiver. The corrected airborne DGPS information, together with the preset approach geometry, is used to calculate guidance commands which are sent to the aircraft's approach guidance instruments. The use of DGPS derived guidance for helicopter approaches to landing is evaluated by comparing the DGPS data with the laser tracker truth data. Both standard (3 deg) and steep (6 deg and 9 deg) glideslope straight-in approaches were flown. DGPS positioning accuracy based on a time history analysis of the entire approach was 0.2 m (mean) +/- 1.8 m (2 sigma) laterally and -2.0 m (mean) +/- 3.5 m (2 sigma) vertically for 3 deg glideslope approaches, -0.1 m (mean) +/- 1.5 m (2 sigma) laterally and -1.1 m (mean) +/- 3.5 m (2 sigma) vertically for 6 deg glideslope approaches and 0.2 m (mean) +/- 1.3 m (2 sigma) laterally and -1.0 m (mean) +/- 2.8 m (2 sigma) vertically for 9 deg glideslope approaches. DGPS positioning accuracy at the 200 ft decision height (DH) on a standard 3 deg slideslope approach was 0.3 m (mean) +/- 1.5 m (2 sigma) laterally and -2.3 m (mean) +/- 1.6 m (2 sigma) vertically. These errors indicate that the helicopter position based on DGPS guidance satisfies the International Civil Aviation Organization (ICAO) Category 1 (CAT 1) lateral and vertical navigational accuracy requirements.

  3. Negative parenting behavior and childhood oppositional defiant disorder: differential moderation by positive and negative peer regard.

    Science.gov (United States)

    Tung, Irene; Lee, Steve S

    2014-01-01

    Although negative parenting behavior and peer status are independently associated with childhood conduct problems (e.g., oppositional defiant disorder (ODD)), relatively little is known about their interplay, particularly in relation to differentiated measures of positive and negative peer regard. To improve the specificity of the association of negative parenting behavior and peer factors with ODD, we explored the potential interaction of parenting and peer status in a sample of 169 five-to ten-year-old ethnically diverse children with and without attention-deficit/hyperactivity disorder (ADHD) assessed using multiple measures (i.e., rating scales, interview) and informants (i.e., parents, teachers). Controlling for children's age, sex, number of ADHD symptoms, and parents' race-ethnicity, peer acceptance inversely predicted and inconsistent discipline, harsh punishment, and peer rejection were each positively associated with ODD symptom severity. Interactive influences were also evident such that inconsistent discipline and harsh punishment each predicted elevated ODD but only among children experiencing low peer acceptance or high peer rejection. These findings suggest that supportive environments, including peer acceptance, may protect children from negative outcomes associated with inconsistent discipline and harsh punishment. Findings are integrated with theories of social support, and we additionally consider implications for intervention and prevention. © 2013 Wiley Periodicals, Inc.

  4. Gamification and the Internet: Experts Expect Game Layers to Expand in the Future, with Positive and Negative Results.

    Science.gov (United States)

    Anderson, Janna; Rainie, Lee

    2012-08-01

    This analysis of the opinions of 1,021 Internet stakeholders was aimed at gauging current opinions about the potential future of game mechanics online. Nearly 5,000 people who are engaged in some way in Internet-related leadership or interests were invited to read a pair of opposing 2020 gamification scenarios and offer their written views on the likely future of gamification online by 2020. The result is not projectable to any population other than these respondents. A slight majority of 53 percent agreed with a proposed scenario that game mechanics will become a part of everyday life for most Internet users by 2020; a great majority of respondents said game elements will play a vital role in specific realms such as health and education by then. Some respondents said people will be resistant if game layers are built into too many aspects of people's daily lives. Some shared concerns that game-design approaches can be used to manipulate people without their knowledge.

  5. Correlation of circRNAs’ differential expression to negative- positive symptoms of patients with schizophrenia

    Directory of Open Access Journals (Sweden)

    Ling-ming KONG

    2017-11-01

    Full Text Available Objective To explore the correlation of circRNAs' expression level to the negative- and positive symptoms of patients with schizophrenia (SZ. Methods Gene chip screening was performed with the peripheral blood samples from each five of SZ patients and normal controls. Nine circRNAs showing differentiate expression were confirmed, and further verification was done by real-time fluorescence quantitative PCR in 102 SZ patients and 103 normal controls. All the SZ patients were assessed with Positive and Negative Symptom Scale (PANSS. Results It was revealed that the expression levels of circRNA_102101, circRNA_102315, circRNA_104597, circRNA_101835 and circRNA_101836 were significantly down-regulated (P<0.01 or P<0.05, and circRNA_103102 and circRNA_103704 were up-regulated in SZ group (P<0.01. The ΔCT value of circRNA_102101 and circRNA_103102 was positively correlated to the positive symptoms (P<0.01 or P<0.05, and the ΔCT value of circRNA_103704 also showed positive correlation with positive symptoms and general psychopathological symptoms (P<0.01 or P<0.05. The ΔCT values of circRNA_102101, circRNA_103102, circRNA_102315, circRNA_103704 and circRNA_102802 were correlated with thinking disorder (P<0.01 or P<0.05, and the ΔCT values of circRNA_102101, circRNA_103102, circRNA_104597, circRNA_103704 and circRNA_102802 were correlated with the activation (P<0.01 or P<0.05. The ΔCT values of circRNA_102101, circRNA_103102, circRNA_103704 and circRNA_102802 were positively correlated with paranoid (P<0.01 or P<0.05, and of circRNA_102101, circRNA_103102, circRNA_103704 and circRNA_102802 were markedly correlated with assault (P<0.01 or P<0.05. Therefore, circRNA_103704 was chosen into regressive equation of positive symptoms (P<0.01, and circRNA_103704 and circRNA_102315 were chosen into regressive equation of general pathological findings (P<0.01 or P<0.05. Conclusion The expression levels of circRNA_103704 and circRNA_103102 are obviously up

  6. Automated Analysis of Facial Cues from Videos as a Potential Method for Differentiating Stress and Boredom of Players in Games

    Directory of Open Access Journals (Sweden)

    Fernando Bevilacqua

    2018-01-01

    Full Text Available Facial analysis is a promising approach to detect emotions of players unobtrusively; however approaches are commonly evaluated in contexts not related to games or facial cues are derived from models not designed for analysis of emotions during interactions with games. We present a method for automated analysis of facial cues from videos as a potential tool for detecting stress and boredom of players behaving naturally while playing games. Computer vision is used to automatically and unobtrusively extract 7 facial features aimed at detecting the activity of a set of facial muscles. Features are mainly based on the Euclidean distance of facial landmarks and do not rely on predefined facial expressions, training of a model, or the use of facial standards. An empirical evaluation was conducted on video recordings of an experiment involving games as emotion elicitation sources. Results show statistically significant differences in the values of facial features during boring and stressful periods of gameplay for 5 of the 7 features. We believe our approach is more user-tailored, convenient, and better suited for contexts involving games.

  7. Differential clinicopathological features in microsatellite instability-positive colorectal cancers depending on CIMP status.

    Science.gov (United States)

    Bae, Jeong Mo; Kim, Mi Jung; Kim, Jung Ho; Koh, Jae Moon; Cho, Nam-Yun; Kim, Tae-You; Kang, Gyeong Hoon

    2011-07-01

    Microsatellite instability-positive (MSI+) colorectal cancers (CRCs) are divided into CpG island methylator phenotype-positive (CIMP+) and CpG island methylator phenotype-negative (CIMP-) tumors. The repertoire of inactivated genes in CIMP+/MSI+ CRCs overlaps with but is likely to differ from that of CIMP-/MSI+ CRCs. Because epigenotypic differences are likely to be manifested as phenotypic differences, CIMP+/MSI+ CRCs are expected to differ from CIMP-/MSI+ CRCs in some clinicopathological features. This study aimed to characterize both common and different features between the two subtypes. A total of 72 MSI+ CRCs were analyzed for their methylation status in eight CIMP panel markers using MethyLight assay. CIMP+/MSI+ and CIMP-/MSI+ CRCs were compared regarding clinicopathologic features and mutation in KRAS/BRAF. An independent set of MSI+ CRCs (n = 97) was analyzed for their relationship of CIMP+ status with clinical outcome. Eighteen cases (25%) were CIMP+, and this CIMP+ subtype was highly correlated with older age (P CIMP-/MSI+ CRCs (18.5%, P = 0.057). CIMP+/MSI+ CRCs were closely associated with poor differentiation, medullary appearance, signet ring cell appearance, and acinar-form appearance, whereas the CIMP-/MSI+ subtype was closely associated with intraglandular eosinophilic mucin and stratified nuclei (all P values CIMP+/MSI+ CRCs showed worse overall survival than patients with CIMP-/MSI+ CRCs. Our results demonstrate heterogeneity in the clinicopathological features of MSI+ CRCs depending on CIMP status. The observation that CIMP+ and CIMP- subtypes showed different clinical behaviors may provide a clue for establishing subtype-specific therapeutic strategies for these two subtypes.

  8. Wealth, Poverty, and Happiness: Social Class Is Differentially Associated With Positive Emotions.

    Science.gov (United States)

    Piff, Paul K; Moskowitz, Jake P

    2017-12-18

    Is higher social class associated with greater happiness? In a large nationally representative U.S. sample (N = 1,519), we examined the association between social class (household income) and self-reported tendencies to experience 7 distinct positive emotions that are core to happiness: amusement, awe, compassion, contentment, enthusiasm, love, and pride. Consistent with past research indicating that social class underlies differential patterns of attending to the self versus orienting to others, higher social class was associated with greater self-oriented feelings of contentment and pride, and with greater amusement. In contrast, lower social class was associated with more other-oriented feelings of compassion and love, and with greater awe. There were no class differences in enthusiasm. We discuss that individuals from different social class backgrounds may exhibit different patterns of emotional responding due to their distinct social concerns and priorities. Whereas self-oriented emotions may follow from, foster, and reinforce upper class individuals' desire for independence and self-sufficiency, greater other-oriented emotion may enable lower class individuals to form more interdependent bonds to cope with their more threatening environments. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  9. Higher-order stochastic differential equations and the positive Wigner function

    Science.gov (United States)

    Drummond, P. D.

    2017-12-01

    General higher-order stochastic processes that correspond to any diffusion-type tensor of higher than second order are obtained. The relationship of multivariate higher-order stochastic differential equations with tensor decomposition theory and tensor rank is explained. Techniques for generating the requisite complex higher-order noise are proved to exist either using polar coordinates and γ distributions, or from products of Gaussian variates. This method is shown to allow the calculation of the dynamics of the Wigner function, after it is extended to a complex phase space. The results are illustrated physically through dynamical calculations of the positive Wigner distribution for three-mode parametric downconversion, widely used in quantum optics. The approach eliminates paradoxes arising from truncation of the higher derivative terms in Wigner function time evolution. Anomalous results of negative populations and vacuum scattering found in truncated Wigner quantum simulations in quantum optics and Bose-Einstein condensate dynamics are shown not to occur with this type of stochastic theory.

  10. Differential Amplitude Pulse-Position Modulation for Indoor Wireless Optical Communications

    Directory of Open Access Journals (Sweden)

    Sethakaset Ubolthip

    2005-01-01

    Full Text Available We propose a novel differential amplitude pulse-position modulation (DAPPM for indoor optical wireless communications. DAPPM yields advantages over PPM, DPPM, and DH-PIM in terms of bandwidth requirements, capacity, and peak-to-average power ratio (PAPR. The performance of a DAPPM system with an unequalized receiver is examined over nondispersive and dispersive channels. DAPPM can provide better bandwidth and/or power efficiency than PAM, PPM, DPPM, and DH-PIM depending on the number of amplitude levels and the maximum length of a symbol. We also show that, given the same maximum length, DAPPM has better bandwidth efficiency but requires about and more power than PPM and DPPM, respectively, at high bit rates over a dispersive channel. Conversely, DAPPM requires less power than DH-PIM . When the number of bits per symbol is the same, PAM requires more power, and DH-PIM less power, than DAPPM. Finally, it is shown that the performance of DAPPM can be improved with MLSD, chip-rate DFE, and multichip-rate DFE.

  11. Promoting Positive Behavior Using the Good Behavior Game: A Meta-Analysis of Single-Case Research

    Science.gov (United States)

    Bowman-Perrott, Lisa; Burke, Mack D.; Zaini, Samar; Zhang, Nan; Vannest, Kimberly

    2016-01-01

    The Good Behavior Game (GBG) is a classroom management strategy that uses an interdependent group-oriented contingency to promote prosocial behavior and decrease problem behavior. This meta-analysis synthesized single-case research (SCR) on the GBG across 21 studies, representing 1,580 students in pre-kindergarten through Grade 12. The TauU effect…

  12. Of virtual victims and victimized virtues: differential effects of experienced aggression in video games on social cooperation.

    Science.gov (United States)

    Rothmund, Tobias; Gollwitzer, Mario; Klimmt, Christoph

    2011-01-01

    Two experimental studies were used to investigate how interacting with aggressive virtual characters in video games affects trust and cooperation of players. Study 1 demonstrates that experiencing virtual aggression from a victim's perspective can impair players' investments in a subsequent common goods dilemma situation. This effect is mediated by reduced expectations of trust in the cooperativeness of interaction partners. In Study 2 the same effect was replicated by using a different cooperation task and by investigating the moderating role of justice sensitivity from a victim's perspective as a dispositional factor. Participants transferred less money to an unknown partner in a trust game after exposure to aggressive nonplayer characters in a video game. This effect was stronger for people high in victim sensitivity. Results of both studies can be interpreted in line with the sensitivity to mean intentions model and add to the body of research on violent media effects.

  13. The Word Has Become Game : Researching Religion in Digital Games

    NARCIS (Netherlands)

    Bosman, Frank

    2016-01-01

    In this article, the author proposes a multi-layered methodology for researching religion in video games. The author differentiates between five levels at which religion can be encountered in video games and/or video game research: material, referential, reflexive, ritual and meta level. These

  14. Existence of positive solutions for multi-term non-autonomous fractional differential equations with polynomial coefficients

    Directory of Open Access Journals (Sweden)

    Azizollah Babakhani

    2006-10-01

    Full Text Available In the present paper we discuss the existence of positive solutions in the case of multi-term non-autonomous fractional differential equations with polynomial coefficients; the constant coefficient case has been studied in [2]. We consider the equation $$ Big(D^{alpha_n} -sum_{j = 1}^{n - 1} p_j(xD^{alpha_{n - j}}Bigy = f(x, y. $$ We state various conditions on $f$ and $p_j$'s under which this equation has: positive solutions, a unique solution which is positive, and a unique solution which may not be positive.

  15. Differential effects of wakeful rest, music and video game playing on working memory performance in the n-back task

    Directory of Open Access Journals (Sweden)

    Maxim S Kuschpel

    2015-10-01

    Full Text Available The interruption of learning processes by breaks filled with diverse activities is common in everyday life. We investigated the effects of active computer gaming and passive relaxation (rest and music breaks on working memory performance. Young adults were exposed to breaks involving (i eyes-open resting, (ii listening to music and (iii playing the video game Angry Birds before performing the n-back working memory task. Based on linear mixed-effects modeling, we found that playing the Angry Birds video game during a short learning break led to a decline in task performance over the course of the task as compared to eyes-open resting and listening to music, although overall task performance was not impaired. This effect was associated with high levels of daily mind wandering and low self-reported ability to concentrate. These findings indicate that video games can negatively affect working memory performance over time when played in between learning tasks. We suggest further investigation of these effects because of their relevance to everyday activity.

  16. Differential effects of wakeful rest, music and video game playing on working memory performance in the n-back task.

    Science.gov (United States)

    Kuschpel, Maxim S; Liu, Shuyan; Schad, Daniel J; Heinzel, Stephan; Heinz, Andreas; Rapp, Michael A

    2015-01-01

    The interruption of learning processes by breaks filled with diverse activities is common in everyday life. We investigated the effects of active computer gaming and passive relaxation (rest and music) breaks on working memory performance. Young adults were exposed to breaks involving (i) eyes-open resting, (ii) listening to music and (iii) playing the video game "Angry Birds" before performing the n-back working memory task. Based on linear mixed-effects modeling, we found that playing the "Angry Birds" video game during a short learning break led to a decline in task performance over the course of the task as compared to eyes-open resting and listening to music, although overall task performance was not impaired. This effect was associated with high levels of daily mind wandering and low self-reported ability to concentrate. These findings indicate that video games can negatively affect working memory performance over time when played in between learning tasks. We suggest further investigation of these effects because of their relevance to everyday activity.

  17. Differential effects of wakeful rest, music and video game playing on working memory performance in the n-back task

    Science.gov (United States)

    Kuschpel, Maxim S.; Liu, Shuyan; Schad, Daniel J.; Heinzel, Stephan; Heinz, Andreas; Rapp, Michael A.

    2015-01-01

    The interruption of learning processes by breaks filled with diverse activities is common in everyday life. We investigated the effects of active computer gaming and passive relaxation (rest and music) breaks on working memory performance. Young adults were exposed to breaks involving (i) eyes-open resting, (ii) listening to music and (iii) playing the video game “Angry Birds” before performing the n-back working memory task. Based on linear mixed-effects modeling, we found that playing the “Angry Birds” video game during a short learning break led to a decline in task performance over the course of the task as compared to eyes-open resting and listening to music, although overall task performance was not impaired. This effect was associated with high levels of daily mind wandering and low self-reported ability to concentrate. These findings indicate that video games can negatively affect working memory performance over time when played in between learning tasks. We suggest further investigation of these effects because of their relevance to everyday activity. PMID:26579055

  18. Asymmetry in Dominant / Non-Dominant Hand Performance Differentiates Novices from Experts on an Arthroscopy Virtual Reality Serious Game.

    Science.gov (United States)

    Pedowitz, Robert; Nicandri, Gregg; Tuchschmid, Stefan

    2016-01-01

    Safe and effective arthroscopic surgery requires ambidextrous motor skills. The current study examined dominant versus non-dominant hand performance on a virtual reality serious game in a group of expert arthroscopic surgeons (n=15) compared to a group of orthopedic surgery residents (n=10). A virtual reality Tetris game was performed with the arthroscopic camera and arthroscope in one hand, using an arthroscopic grasping tool in the opposite hand to manipulate the virtual Tetris blocks onto the game grid. A second run was performed after swapping instruments between hands. The order of hand testing was randomized. There was no statistically significant difference in exercise time, grasper path length, or camera path length between the right and left hands of the expert surgeons. In contrast, there were statistically significant differences in all of these parameters between the two hands for the orthopedic surgery residents, with better performance when the grasping tool was used in the dominant hand. The findings of this study suggest that virtual reality games which incorporate progressive cognitive loading could be used to facilitate training, automation, and objective assessment of surgical motor skills.

  19. Multiplayer computer games as youth's leisure phenomenon

    OpenAIRE

    HADERKOVÁ, Barbora

    2016-01-01

    The thesis is dedicated to multiplayer computer games as youth's leisure phenomenon of this time. The theoretical part is focused on computer games history, multiplayer computer games and their types, gaming platforms, community of multiplayer games players and potential negatives and positives, which follows from playing this type of games. The practical part contains a qualitative survey using interviews with multiplayer computer games players aged from 15 to 26 years from city of České Bud...

  20. Epic Allies: Development of a Gaming App to Improve Antiretroviral Therapy Adherence Among Young HIV-Positive Men Who Have Sex With Men.

    Science.gov (United States)

    LeGrand, Sara; Muessig, Kathryn Elizabeth; McNulty, Tobias; Soni, Karina; Knudtson, Kelly; Lemann, Alex; Nwoko, Nkechinyere; Hightow-Weidman, Lisa B

    2016-05-13

    In the United States, the human immunodeficiency virus (HIV) disproportionately affects young men who have sex with men (YMSM). For HIV-positive individuals, adherence to antiretroviral therapy (ART) is critical for achieving optimal health outcomes and reducing secondary transmission of HIV. However, YMSM often struggle with ART adherence. Novel mobile phone apps that incorporate game-based mechanics and social networking elements represent a promising intervention approach for improving ART adherence among YMSM. This study used a multiphase, iterative development process to create an ART adherence app for YMSM. The three-phase development process included: (1) theory-based concept development jointly by public health researchers and the technology team, (2) assessment of the target population's ART adherence needs and app preferences and development and testing of a clickable app prototype, and (3) development and usability testing of the final app prototype. The initial theory-based app concept developed in Phase One included medication reminders, daily ART adherence tracking and visualization, ART educational modules, limited virtual interactions with other app users, and gamification elements. In Phase Two, adherence needs, including those related to information, motivation, and behavioral skills, were identified. Participants expressed preferences for an ART adherence app that was informational, interactive, social, and customizable. Based on the findings from Phase Two, additional gaming features were added in Phase Three, including an interactive battle, superhero app theme, and app storyline. Other features were modified to increase interactivity and customization options and integrate the game theme. During usability testing of the final prototype, participants were able to understand and navigate the app successfully and rated the app favorably. An iterative development process was critical for the development of an ART adherence game app that was viewed

  1. Online Games

    OpenAIRE

    Kerr, Aphra; Ivory, James D.

    2015-01-01

    When we agreed to edit the theme on online games for this Encyclopedia our first question was, “What is meant by online games?” Scholars of games distinguish between nondigital games (such as board games) and digital games, rather than between online and offline games. With networked consoles and smartphones it is becoming harder and harder to find players in the wealthy industrialized countries who play “offline” digital games. Most games developers now include ...

  2. A Mixed Monotone Operator Method for the Existence and Uniqueness of Positive Solutions to Impulsive Caputo Fractional Differential Equations

    Directory of Open Access Journals (Sweden)

    Jieming Zhang

    2013-01-01

    Full Text Available We establish some sufficient conditions for the existence and uniqueness of positive solutions to a class of initial value problem for impulsive fractional differential equations involving the Caputo fractional derivative. Our analysis relies on a fixed point theorem for mixed monotone operators. Our result can not only guarantee the existence of a unique positive solution but also be applied to construct an iterative scheme for approximating it. An example is given to illustrate our main result.

  3. Positive nondecreasing solutions for a multi-term fractional-order functional differential equation with integral conditions

    Directory of Open Access Journals (Sweden)

    Ahmed M. A. El-Sayed

    2011-12-01

    Full Text Available In this article, we prove the existence of positive nondecreasing solutions for a multi-term fractional-order functional differential equations. We consider Cauchy boundary problems with: nonlocal conditions, two-point boundary conditions, integral conditions, and deviated arguments.

  4. Microtransactions in an Android Game

    OpenAIRE

    Kokkonen, Teemu

    2014-01-01

    The objective of this thesis is to explore the products sold within mobile applications and games, called in-app purchases or microtransactions. The thesis studies the history and nature of these microtransactions and examines their positive and negative effects on game design, as well as analyzes their usage in modern mobile games. To reinforce the research, a mobile game codenamed TownBuilder was developed alongside the thesis. The game paid attention to the designs explored in the earl...

  5. Relating Specific Emotions to Intrinsic Motivation: On the Moderating Role of Positive and Negative Emotion Differentiation

    OpenAIRE

    Vandercammen, Leen; Hofmans, Joeri; Theuns, Peter

    2014-01-01

    Despite the fact that studies on self-determination theory have traditionally disregarded the explicit role of emotions in the motivation eliciting process, research attention for the affective antecedents of motivation is growing. We add to this emerging research field by testing the moderating role of emotion differentiation -individual differences in the extent to which people can differentiate between specific emotions- on the relationship between twelve specific emotions and intrinsic mo...

  6. Reversible immortalization of Nestin-positive precursor cells from pancreas and differentiation into insulin-secreting cells

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Pei; Li, Li; Qi, Hui [The Clinical Medical Research Center, The Second Clinical Medical College (Shenzhen People' s Hospital), Jinan University, 518020 Shenzhen (China); Zhou, Han-xin [Department of General Surgery, First Hospital (Shenzhen Second People' s Hospital) of Shenzhen University, 518020 Shenzhen (China); Deng, Chun-yan [The Clinical Medical Research Center, The Second Clinical Medical College (Shenzhen People' s Hospital), Jinan University, 518020 Shenzhen (China); Li, Fu-rong, E-mail: frli62@yahoo.com [The Clinical Medical Research Center, The Second Clinical Medical College (Shenzhen People' s Hospital), Jinan University, 518020 Shenzhen (China); Shenzhen Institution of Gerontology, 518020 Shenzhen (China)

    2012-02-10

    Highlights: Black-Right-Pointing-Pointer The NPPCs from mouse pancreas were isolated. Black-Right-Pointing-Pointer Tet-on system for SV40 large in NPPCs was used to get RINPPCs. Black-Right-Pointing-Pointer The RINPPCs can undergo at least 80 population doublings without senescence. Black-Right-Pointing-Pointer The RINPPCs can be induced to differentiate into insulin-producing cells. Black-Right-Pointing-Pointer The combination of GLP-1 and sodium butyrate promoted the differentiation process. -- Abstract: Pancreatic stem cells or progenitor cells posses the ability of directed differentiation into pancreatic {beta} cells. However, these cells usually have limited proliferative capacity and finite lifespan in vitro. In the present study, Nestin-positive progenitor cells (NPPCs) from mouse pancreas that expressed the pancreatic stem cells or progenitor cell marker Nestin were isolated to obtain a sufficient number of differentiated pancreatic {beta} cells. Tet-on system for SV40 large T-antigen expression in NPPCs was used to achieve reversible immortalization. The reversible immortal Nestin-positive progenitor cells (RINPPCs) can undergo at least 80 population doublings without senescence in vitro while maintaining their biological and genetic characteristics. RINPPCs can be efficiently induced to differentiate into insulin-producing cells that contain a combination of glucagon-like peptide-1 (GLP-1) and sodium butyrate. The results of the present study can be used to explore transplantation therapy of type I diabetes mellitus.

  7. Distribution of events of positive selection and population differentiation in a metabolic pathway: the case of asparagine N-glycosylation

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    Dall’Olio Giovanni

    2012-06-01

    Full Text Available Abstract Background Asparagine N-Glycosylation is one of the most important forms of protein post-translational modification in eukaryotes. This metabolic pathway can be subdivided into two parts: an upstream sub-pathway required for achieving proper folding for most of the proteins synthesized in the secretory pathway, and a downstream sub-pathway required to give variability to trans-membrane proteins, and involved in adaptation to the environment and innate immunity. Here we analyze the nucleotide variability of the genes of this pathway in human populations, identifying which genes show greater population differentiation and which genes show signatures of recent positive selection. We also compare how these signals are distributed between the upstream and the downstream parts of the pathway, with the aim of exploring how forces of population differentiation and positive selection vary among genes involved in the same metabolic pathway but subject to different functional constraints. Results Our results show that genes in the downstream part of the pathway are more likely to show a signature of population differentiation, while events of positive selection are equally distributed among the two parts of the pathway. Moreover, events of positive selection are frequent on genes that are known to be at bifurcation points, and that are identified as being in key position by a network-level analysis such as MGAT3 and GCS1. Conclusions These findings indicate that the upstream part of the Asparagine N-Glycosylation pathway has lower diversity among populations, while the downstream part is freer to tolerate diversity among populations. Moreover, the distribution of signatures of population differentiation and positive selection can change between parts of a pathway, especially between parts that are exposed to different functional constraints. Our results support the hypothesis that genes involved in constitutive processes can be expected to show

  8. Social Capital and Online Games

    OpenAIRE

    Safferling, Christoph

    2011-01-01

    We use data from an online game economy and econometric matching methods to test whether social capital of players has an impact on game success. Membership in a 'clan', a voluntary organization of players, positively impacts game success. Hence, social capital has a positive effect on outcomes. Yet, top performers do not gain from access to this social capital.

  9. Productive Gaming

    OpenAIRE

    Brandstätter , Ulrich; Sommerer , Christa

    2016-01-01

    Part 4: Short Papers; International audience; Video games can be appropriated for productive purposes. Commercial games and game engines are often used for video productions, and game development companies provide development kits and modding environments to gaming communities and independent developers. With gamification, game principles are deployed in non-game contexts for benefits beyond pure entertainment. Most approaches are more focused on using games and their design elements rather t...

  10. Differentiating Three Conceptualisations of the Relationship between Positive Development and Psychopathology during the Transition to Adulthood

    Science.gov (United States)

    O'Connor, Meredith; Sanson, Ann; Hawkins, Mary T.; Toumbourou, John W.; Letcher, Primrose; Frydenberg, Erica

    2011-01-01

    The transition to adulthood is characterised by both great potential for positive change and a relatively high incidence of problem outcomes. A multidimensional model of positive development during the transition to adulthood (at 19-20 years) has recently been proposed. However, an unresolved question regarding the nature of positive development…

  11. Elementos diferenciales en la forma audiovisual de los videojuegos. Vinculación, presencia e inmersión. Differential elements in the audiovisual form of the video games. Bonding, presence and immersion.

    Directory of Open Access Journals (Sweden)

    María Gabino Campos

    2012-01-01

    Full Text Available In just over two decades the video games reach the top positions in the audiovisual sector. Different technical, economic and social facts make that video games are the main reference of entertainment for a growing number of millions. This phenomenon is also due to its creators develop stories with elements of interaction in order to achieve high investment of time by users. We investigate the concepts of bonding, presence and immersion for its implications in the sensory universe of video games and we show the state of the audiovisual research in this field in the first decade of the century.

  12. New Positive and Negative Hierarchies of Integrable Differential-Difference Equations and Conservation Laws

    International Nuclear Information System (INIS)

    Li Xinyue; Zhao Qiulan

    2009-01-01

    Two hierarchies of nonlinear integrable positive and negative lattice equations are derived from a discrete spectral problem. The two lattice hierarchies are proved to have discrete zero curvature representations associated with a discrete spectral problem, which also shows that the positive and negative hierarchies correspond to positive and negative power expansions of Lax operators with respect to the spectral parameter, respectively. Moreover, the integrable lattice models in the positive hierarchy are of polynomial type, and the integrable lattice models in the negative hierarchy are of rational type. Further, we construct infinite conservation laws about the positive hierarchy.

  13. Supermodular Games and Potential Games

    NARCIS (Netherlands)

    Brânzei, R.; Mallozzi, L.; Tijs, S.H.

    2001-01-01

    Potential games and supermodular games are attractive games, especially because under certain conditions they possess pure Nash equilibria. Subclasses of games with a potential are considered which are also strategically equivalent to supermodular games. The focus is on two-person zero-sum games and

  14. Positional cloning of the PIS mutation in goats and its impact on understanding mammalian sex-differentiation

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    Pailhoux Eric

    2005-12-01

    Full Text Available Abstract In goats, the PIS (polled intersex syndrome mutation is responsible for both the absence of horns in males and females and sex-reversal affecting exclusively XX individuals. The mode of inheritance is dominant for the polled trait and recessive for sex-reversal. In XX PIS-/- mutants, the expression of testis-specific genes is observed very precociously during gonad development. Nevertheless, a delay of 4–5 days is observed in comparison with normal testis differentiation in XY males. By positional cloning, we demonstrate that the PIS mutation is an 11.7-kb regulatory-deletion affecting the expression of two genes, PISRT1 and FOXL2 which could act synergistically to promote ovarian differentiation. The transcriptional extinction of these two genes leads, very early, to testis-formation in XX homozygous PIS-/- mutants. According to their expression profiles and bibliographic data, we propose that FOXL2 may be an ovary-differentiating gene, and the non-coding RNA PISRT1, an anti-testis factor repressing SOX9, a key regulator of testis differentiation. Under this hypothesis, SRY, the testis-determining factor would inhibit these two genes in the gonads of XY males, to ensure testis differentiation.

  15. Triple Positive Solutions of a Nonlocal Boundary Value Problem for Singular Differential Equations with p-Laplacian

    Directory of Open Access Journals (Sweden)

    Jufang Wang

    2013-01-01

    Full Text Available We establish the existence of triple positive solutions of an m-point boundary value problem for the nonlinear singular second-order differential equations of mixed type with a p-Laplacian operator by Leggett-William fixed point theorem. At last, we give an example to demonstrate the use of the main result of this paper. The conclusions in this paper essentially extend and improve the known results.

  16. FGF7 and cell density are required for final differentiation of pancreatic amylase-positive cells from human ES cells.

    Science.gov (United States)

    Takizawa-Shirasawa, Sakiko; Yoshie, Susumu; Yue, Fengming; Mogi, Akimi; Yokoyama, Tadayuki; Tomotsune, Daihachiro; Sasaki, Katsunori

    2013-12-01

    The major molecular signals of pancreatic exocrine development are largely unknown. We examine the role of fibroblast growth factor 7 (FGF7) in the final induction of pancreatic amylase-containing exocrine cells from induced-pancreatic progenitor cells derived from human embryonic stem (hES) cells. Our protocol consisted in three steps: Step I, differentiation of definitive endoderm (DE) by activin A treatment of hES cell colonies; Step II, differentiation of pancreatic progenitor cells by re-plating of the cells of Step I onto 24-well plates at high density and stimulation with all-trans retinoic acid; Step III, differentiation of pancreatic exocrine cells with a combination of FGF7, glucagon-like peptide 1 and nicotinamide. The expression levels of pancreatic endodermal markers such as Foxa2, Sox17 and gut tube endoderm marker HNF1β were up-regulated in both Step I and II. Moreover, in Step III, the induced cells expressed pancreatic markers such as amylase, carboxypeptidase A and chymotrypsinogen B, which were similar to those in normal human pancreas. From day 8 in Step III, cells immunohistochemically positive for amylase and for carboxypeptidase A, a pancreatic exocrine cell product, were induced by FGF7. Pancreatic progenitor Pdx1-positive cells were localized in proximity to the amylase-positive cells. In the absence of FGF7, few amylase-positive cells were identified. Thus, our three-step culture protocol for human ES cells effectively induces the differentiation of amylase- and carboxypeptidase-A-containing pancreatic exocrine cells.

  17. Children's Video Games as Interactive Racialization

    OpenAIRE

    Martin, Cathlena

    2008-01-01

    Cathlena Martin explores in her paper "Children's Video Games as Interactive Racialization" selected children's video games. Martin argues that children's video games often act as reinforcement for the games' television and film counterparts and their racializing characteristics and features. In Martin's analysis the video games discussed represent media through which to analyze racial identities and ideologies. In making the case for positive female minority leads in children's video games, ...

  18. Differential Effects of Positive versus Negative Self-Involving Counselor Responses.

    Science.gov (United States)

    Remer, Pam; And Others

    1983-01-01

    Investigated the effects of positive and negative counselor disclosure using typescripts of hypothetical counseling interviews. Results indicated impact of condition was mixed, with each having some desirable effects. (PAS)

  19. Differentiation of toxoplasmosis and lymphoma in HIV-positive patients with gadolinium-enhanced MR imaging

    International Nuclear Information System (INIS)

    Eisenberg, A.D.; Mani, J.R.; Norman, D.

    1990-01-01

    This paper determines whether gadolinium-enhanced MR imaging can be used to differentiate toxoplasmosis and lymphoma in patients with acquired immunodeficiency syndrome. One hundred fifty-nine lesions from 71 MR examinations of eight patients with lymphoma were evaluated for size, location, enhancement characteristics, lesion multiplicity. Multiple lesions occurred in 72% of toxoplasmosis and 75% of lymphoma cases. Toxoplasmosis lesions are smaller, with lesion most commonly between 1 and 2 cm, whereas lymphoma is most often between 2 and 3 cm. Except for a propensity for lymphoma to occur in the temporal lobes, no difference in lesion location was found. Both conditions usually markedly enhance, but the pattern of enhancement differs

  20. Differential Potency of 2,6-Dimethylcyclohexanol Isomers for Positive Modulation of GABAA Receptor Currents.

    Science.gov (United States)

    Chowdhury, Luvana; Croft, Celine J; Goel, Shikha; Zaman, Naina; Tai, Angela C-S; Walch, Erin M; Smith, Kelly; Page, Alexandra; Shea, Kevin M; Hall, C Dennis; Jishkariani, D; Pillai, Girinath G; Hall, Adam C

    2016-06-01

    GABAA receptors meet all of the pharmacological requirements necessary to be considered important targets for the action of general anesthetic agents in the mammalian brain. In the following patch-clamp study, the relative modulatory effects of 2,6-dimethylcyclohexanol diastereomers were investigated on human GABAA (α1β3γ2s) receptor currents stably expressed in human embryonic kidney cells. Cis,cis-, trans,trans-, and cis,trans-isomers were isolated from commercially available 2,6-dimethylcyclohexanol and were tested for positive modulation of submaximal GABA responses. For example, the addition of 30 μM cis,cis-isomer resulted in an approximately 2- to 3-fold enhancement of the EC20 GABA current. Coapplications of 30 μM 2,6-dimethylcyclohexanol isomers produced a range of positive enhancements of control GABA responses with a rank order for positive modulation: cis,cis > trans,trans ≥ mixture of isomers > > cis,trans-isomer. In molecular modeling studies, the three cyclohexanol isomers bound with the highest binding energies to a pocket within transmembrane helices M1 and M2 of the β3 subunit through hydrogen-bonding interactions with a glutamine at the 224 position and a tyrosine at the 220 position. The energies for binding to and hydrogen-bond lengths within this pocket corresponded with the relative potencies of the agents for positive modulation of GABAA receptor currents (cis,cis > trans,trans > cis,trans-2,6-dimethylcyclohexanol). In conclusion, the stereochemical configuration within the dimethylcyclohexanols is an important molecular feature in conferring positive modulation of GABAA receptor activity and for binding to the receptor, a consideration that needs to be taken into account when designing novel anesthetics with enhanced therapeutic indices. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  1. International positioning of South African electricity prices and commodity differentiated pricing

    Directory of Open Access Journals (Sweden)

    George A. Thopila

    2013-07-01

    Full Text Available The South African electricity industry has seen a dramatic increase in prices over the past 3 years. This increase has been blanketed across all sectors and is based on a number of factors such as sector, usage and, in the case of domestic pricing, suburb. The cost of electricity in South Africa, particularly to the industrial sector, has been among the lowest in the world. In this paper, we analyse the recent price increases in the South African electricity sector and discuss the price determination mechanism employed by Eskom, South Africa's electricity provider. We also analyse the revenue and sales of Eskom and review the electricity price from an international perspective. The concept of differential pricing and international benchmarking is analysed as a possibility for the South African industrial electricity industry, so that all sectors are not adversely affected by across-the-board increases. Our aim is to raise the question of whether South Africa's electricity prices are in line with international increases and to suggest the possibility of differentiated prices in the local electricity sector.

  2. Positivity of Fundamental Matrix and Exponential Stability of Delay Differential System

    Directory of Open Access Journals (Sweden)

    Alexander Domoshnitsky

    2014-01-01

    Full Text Available The classical Wazewski theorem established that nonpositivity of all nondiagonal elements pij  (i≠j,  i,j=1,…,n is necessary and sufficient for nonnegativity of the fundamental (Cauchy matrix and consequently for applicability of the Chaplygin approach of approximate integration for system of linear ordinary differential equations xi′t+∑j=1n‍pijtxjt=fit,   i=1,…,n. Results on nonnegativity of the Cauchy matrix for system of delay differential equations xi′t+∑j=1n‍pijtxjhijt=fit,   i=1,…,n, which were based on nonpositivity of all diagonal elements, were presented in the previous works. Then examples, which demonstrated that nonpositivity of nondiagonal coefficients pij is not necessary for systems of delay equations, were found. In this paper first sufficient results about nonnegativity of the Cauchy matrix of the delay system without this assumption are proven. A necessary condition of nonnegativity of the Cauchy matrix is proposed. On the basis of these results on nonnegativity of the Cauchy matrix, necessary and sufficient conditions of the exponential stability of the delay system are obtained.

  3. Game theory : Noncooperative games

    NARCIS (Netherlands)

    van Damme, E.E.C.; Wright, J.

    2015-01-01

    We describe noncooperative game models and discuss game theoretic solution concepts. Some applications are also noted. Conventional theory focuses on the question ‘how will rational players play?’, and has the Nash equilibrium at its core. We discuss this concept and its interpretations, as well as

  4. A positive effect of flowers rather than eye images in a large-scale, cross-cultural dictator game.

    Science.gov (United States)

    Raihani, Nichola J; Bshary, Redouan

    2012-09-07

    People often consider how their behaviour will be viewed by others, and may cooperate to avoid gaining a bad reputation. Sensitivity to reputation may be elicited by subtle social cues of being watched: previous studies have shown that people behave more cooperatively when they see images of eyes rather than control images. Here, we tested whether eye images enhance cooperation in a dictator game, using the online labour market Amazon Mechanical Turk (AMT). In contrast to our predictions and the results of most previous studies, dictators gave away more money when they saw images of flowers rather than eye images. Donations in response to eye images were not significantly different to donations under control treatments. Dictator donations varied significantly across cultures but there was no systematic variation in responses to different image types across cultures. Unlike most previous studies, players interacting via AMT may feel truly anonymous when making decisions and, as such, may not respond to subtle social cues of being watched. Nevertheless, dictators gave away similar amounts as in previous studies, so anonymity did not erase helpfulness. We suggest that eye images might only promote cooperative behaviour in relatively public settings and that people may ignore these cues when they know their behaviour is truly anonymous.

  5. Gaming Personality and Game Dynamics in Online Discussion Instructions

    Science.gov (United States)

    Tu, Chih-Hsiung; Yen, Cherng-Jyh; Sujo-Montes, Laura; Roberts, Gayle A.

    2015-01-01

    Gamification is the use of game mechanics to drive game-like engagements and actions. It applies game mechanics, dynamics and frameworks to promote desired learning behaviours. Positive and effective gamification could enhance learning and engage learners in more social and context-rich decision-making for problem-solving in learning tasks.…

  6. Multi-Unmanned Aerial Vehicle (UAV) Cooperative Fault Detection Employing Differential Global Positioning (DGPS), Inertial and Vision Sensors.

    Science.gov (United States)

    Heredia, Guillermo; Caballero, Fernando; Maza, Iván; Merino, Luis; Viguria, Antidio; Ollero, Aníbal

    2009-01-01

    This paper presents a method to increase the reliability of Unmanned Aerial Vehicle (UAV) sensor Fault Detection and Identification (FDI) in a multi-UAV context. Differential Global Positioning System (DGPS) and inertial sensors are used for sensor FDI in each UAV. The method uses additional position estimations that augment individual UAV FDI system. These additional estimations are obtained using images from the same planar scene taken from two different UAVs. Since accuracy and noise level of the estimation depends on several factors, dynamic replanning of the multi-UAV team can be used to obtain a better estimation in case of faults caused by slow growing errors of absolute position estimation that cannot be detected by using local FDI in the UAVs. Experimental results with data from two real UAVs are also presented.

  7. The differential effects of position, ad and reader characteristics on readers' processing of newspaper ads

    NARCIS (Netherlands)

    Smit, E.G.; Neijens, P.C.; Heath, R.

    2013-01-01

    Building on previous research on the processing of newspaper ads, this comprehensive field study, with 26,556 newspaper readers and 290 unique advertisements, investigated the combined effects of position in the newspaper, ad characteristics and reader characteristics. The results show a

  8. Imagined Positive Emotions and Inhibitory Control: The Differentiated Effect of Pride versus Happiness

    Science.gov (United States)

    Katzir, Maayan; Eyal, Tal; Meiran, Nachshon; Kessler, Yoav

    2010-01-01

    "Inhibitory control" is a cognitive mechanism that contributes to successful self-control (i.e., adherence to a long-term goal in the face of an interfering short-term goal). This research explored the effect of imagined positive emotional events on inhibition. The authors proposed that the influence of imagined emotions on inhibition…

  9. Fuzzy path tracking and position estimation of autonomous vehicles using differential GPS

    OpenAIRE

    Rodríguez Castaño, Ángel; Heredia Benot, José Guillermo; Ollero Baturone, Aníbal

    2000-01-01

    This paper presents an autonomous vehicle position estimation system based on GPS, that uses a fuzzy sensor fusion technique. A fuzzy path tracking algorithm is also proposed. Both systems have been implemented in the ROMEO-4R vehicle developed at the University of Seville.

  10. Affect and craving: positive and negative affect are differentially associated with approach and avoidance inclinations.

    Science.gov (United States)

    Schlauch, Robert C; Gwynn-Shapiro, Daniel; Stasiewicz, Paul R; Molnar, Danielle S; Lang, Alan R

    2013-04-01

    Research on reactivity to alcohol and drug cues has either ignored affective state altogether or has focused rather narrowly on the role of negative affect in craving. Moreover, until recently, the relevant analyses of affect and craving have rarely addressed the ambivalence often associated with craving itself. The current study investigated how both negative and positive affect moderate approach and avoidance inclinations associated with cue-elicited craving in a clinical sample diagnosed with substance use disorders. One hundred forty-four patients (age range of 18-65, mean 42.0; n=92 males) were recruited from an inpatient detoxification unit for substance abuse. Participants completed a baseline assessment of both positive and negative affect prior to completing a cue-reactivity paradigm for which they provided self-report ratings of inclinations to approach (use) and avoid (not use) alcohol, cigarettes, and non-psychoactive control substances (food and beverages). Participants with elevated negative affect reported significantly higher approach ratings for cigarette and alcohol cues, whereas those high in positive affect showed significantly higher levels of avoidance inclinations for both alcohol and cigarette cues and also significantly lower approach ratings for alcohol cues, all relative to control cues. Results for negative affect are consistent with previous cue reactivity research, whereas results for positive affect are unique and call attention to its clinical potential for attenuating approach inclinations to substance use cues. Further, positive affect was related to both approach and avoidance inclinations, underscoring the utility of a multidimensional conceptualization of craving in the analysis. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Kansei games : entertaining your emotions

    NARCIS (Netherlands)

    Salem, B.I.; Nakatsu, R.

    2007-01-01

    Essentially Kansei Games are a new concept of games that focus on delivering a constructive positive experience to the game player. We wish to do this by addressing the player needs, requirements and desires. We propose a Needs Requirements and Desires (NRD) model where the self is at the centre,

  12. Video game addiction, ADHD symptomatology, and video game reinforcement.

    Science.gov (United States)

    Mathews, Christine L; Morrell, Holly E R; Molle, Jon E

    2018-06-06

    Up to 23% of people who play video games report symptoms of addiction. Individuals with attention deficit hyperactivity disorder (ADHD) may be at increased risk for video game addiction, especially when playing games with more reinforcing properties. The current study tested whether level of video game reinforcement (type of game) places individuals with greater ADHD symptom severity at higher risk for developing video game addiction. Adult video game players (N = 2,801; Mean age = 22.43, SD = 4.70; 93.30% male; 82.80% Caucasian) completed an online survey. Hierarchical multiple linear regression analyses were used to test type of game, ADHD symptom severity, and the interaction between type of game and ADHD symptomatology as predictors of video game addiction severity, after controlling for age, gender, and weekly time spent playing video games. ADHD symptom severity was positively associated with increased addiction severity (b = .73 and .68, ps .05. The relationship between ADHD symptom severity and addiction severity did not depend on the type of video game played or preferred most, ps > .05. Gamers who have greater ADHD symptom severity may be at greater risk for developing symptoms of video game addiction and its negative consequences, regardless of type of video game played or preferred most. Individuals who report ADHD symptomatology and also identify as gamers may benefit from psychoeducation about the potential risk for problematic play.

  13. Discriminatory power of water polo game-related statistics at the 2008 Olympic Games.

    Science.gov (United States)

    Escalante, Yolanda; Saavedra, Jose M; Mansilla, Mirella; Tella, Victor

    2011-02-01

    The aims of this study were (1) to compare water polo game-related statistics by context (winning and losing teams) and sex (men and women), and (2) to identify characteristics discriminating the performances for each sex. The game-related statistics of the 64 matches (44 men's and 20 women's) played in the final phase of the Olympic Games held in Beijing in 2008 were analysed. Unpaired t-tests compared winners and losers and men and women, and confidence intervals and effect sizes of the differences were calculated. The results were subjected to a discriminant analysis to identify the differentiating game-related statistics of the winning and losing teams. The results showed the differences between winning and losing men's teams to be in both defence and offence, whereas in women's teams they were only in offence. In men's games, passing (assists), aggressive play (exclusions), centre position effectiveness (centre shots), and goalkeeper defence (goalkeeper-blocked 5-m shots) predominated, whereas in women's games the play was more dynamic (possessions). The variable that most discriminated performance in men was goalkeeper-blocked shots, and in women shooting effectiveness (shots). These results should help coaches when planning training and competition.

  14. Job stress, occupational position and gender as factors differentiating workplace bullying experience.

    Science.gov (United States)

    Drabek, Marcin; Merecz, Dorota

    2013-01-01

    The results of our research broaden the knowledge concerning the correlates of mobbing. The study is aimed at finding out whether an employee's gender, his/her occupational position and level of occupational stress are related to bullying experience. 1313 employees of a transport company participated in the study. The relationships between gender, occupational position, the level of stress and bullying were analysed. Bullying was measured by the use of the MD)M Questionnaire, while work environment was assessed using the Subjective Assessment of Work Questionnaire. It was found that women were generally more exposed to bullying than men (Z = -1.999; p company, its organisational culture as well as its situation. Therefore it's difficult to talk about irrefutable individual correlates of bullying at work.

  15. Inequalities in child mortality in Mozambique: differentials by parental socio-economic position

    DEFF Research Database (Denmark)

    Macassa, Gloria; Ghilagaber, Gebrenegus; Bernhardt, Eva

    2003-01-01

    This study investigates the relation between socio-economic parental position (education and occupation) and child death in Mozambique using data from the Mozambican Demographic and Health Survey carried out between March and July 1997. The analysis included 9142 children born within 10 years...... before the survey. In spite of the Western system of classification used in the study, the results partly showed a parental socio-economic gradient of infant and child mortality in Mozambique. Father's education seemed to reflect the family's social standing in the Mozambique context, showing a strong...... statistical association with postneonatal and child mortality. However, maternal education as a measure of socio-economic position was not statistically significantly associated with child mortality. This finding may partly be explained by the extreme hardships experienced by the country (civil war...

  16. Convex games versus clan games

    NARCIS (Netherlands)

    Brânzei, R.; Dimitrov, D.A.; Tijs, S.H.

    2008-01-01

    In this paper we provide characterizations of convex games and total clan games by using properties of their corresponding marginal games. We show that a "dualize and restrict" procedure transforms total clan games with zero worth for the clan into monotonic convex games. Furthermore, each monotonic

  17. Convex Games versus Clan Games

    NARCIS (Netherlands)

    Brânzei, R.; Dimitrov, D.A.; Tijs, S.H.

    2006-01-01

    In this paper we provide characterizations of convex games and total clan games by using properties of their corresponding marginal games.We show that a "dualize and restrict" procedure transforms total clan games with zero worth for the clan into monotonic convex games.Furthermore, each monotonic

  18. Game on! : Evaluation malaria games

    NARCIS (Netherlands)

    Rob Willems

    2014-01-01

    The goal of GameOn! is to develop a serious video game. The object: to develop a serious game that aims to change behavior through awareness. The setup A multidisciplinary group which unites expertise from didactic and game production backgrounds produces an educational game for an international

  19. Game mechanics : advanced game design

    NARCIS (Netherlands)

    Adams, Ernest; Dormans, Joris

    2012-01-01

    Game Mechanics is aimed at game design students and industry professionals who want to improve their understanding of how to design, build, and test the mechanics of a game. Game Mechanics will show you how to design, test, and tune the core mechanics of a game—any game, from a huge role-playing

  20. A ppendicitis with Positive Ultrasound and its Relation to Total and Differential Leucocytic Count

    International Nuclear Information System (INIS)

    Saleh, G.M.; Sabek, E.A.S.; Elessiely, E.S.; Ibrahim, E.M.

    2016-01-01

    Background:The most common cause of acute surgical abdomen is acute appendicitis and the most commonly done emergency surgery is appendectomy. Although a battery of tests and different scoring methods are available for diagnosis of acute appendicitis, it is very difficult to prevent negative explorations for appendicectomy (15 - 30%). None of the tests has satisfactory Sensitivity and specificity that can be relied upon. Objectives: The aim of the present study was to evaluate the role of total and differential leukocyte count, and ultrasonography (USG) of abdomen in diagnosing acute appendicitis and reducing the rates of negative appendicectomies and to prevent complications like perforation, peritonitis, and the longer the delay between diagnosis and surgery, the more likely is the perforation leading to peritonitis. In addition, emphasis was given to whether combining the investigations for the same patient would improve the diagnostic accuracy. Materials and Methods : A total of 76 clinically diagnosed patients of acute appendicitis, posted for emergency appendicectomy were included in the study in General Surgery Department of EL-Salam Hospital. This study was conducted in the period October 2012 to September 2013. Preoperatively blood tests for, total leukocyte count, differential leukocyte count(DLC) and USG abdomen were done. All patients were subjected to histological examination postoperatively, which was taken as the gold standard. The three investigations results were correlated with histopathological examination reports to evaluate their role in diagnosis of acute appendicitis. Results: In the present study, the US has the highest sensitivity and specificity (90%, 80%) followed by Total leucocyte count (87.5%, 90%), white Neutrophil count (78.75%, 80%). Combining US and WBC count increases the sensitivity and specificity of the tests (96.25%, 80%). Conclusion: US contains important diagnostic information and hence should always be included in the

  1. Impartial Triangular Chocolate Bar Games

    OpenAIRE

    Miyadera, Ryohei; Nakamura, Shunsuke; Fukui, Masanori

    2017-01-01

    Chocolate bar games are variants of the game of Nim in which the goal is to leave your opponent with the single bitter part of the chocolate bar. The rectangular chocolate bar game is a thinly disguised form of classical multi-heap Nim. In this work, we investigate the mathematical structure of triangular chocolate bar games in which the triangular chocolate bar can be cut in three directions. In the triangular chocolate bar game, a position is a $\\mathcal{P}$-position if and only if $x \\oplu...

  2. Financial Incentives Differentially Regulate Neural Processing of Positive and Negative Emotions during Value-Based Decision-Making

    Directory of Open Access Journals (Sweden)

    Anne M. Farrell

    2018-02-01

    Full Text Available Emotional and economic incentives often conflict in decision environments. To make economically desirable decisions then, deliberative neural processes must be engaged to regulate automatic emotional reactions. In this functional magnetic resonance imaging (fMRI study, we evaluated how fixed wage (FW incentives and performance-based (PB financial incentives, in which pay is proportional to outcome, differentially regulate positive and negative emotional reactions to hypothetical colleagues that conflicted with the economics of available alternatives. Neural activity from FW to PB incentive contexts decreased for positive emotional stimuli but increased for negative stimuli in middle temporal, insula, and medial prefrontal regions. In addition, PB incentives further induced greater responses to negative than positive emotional decisions in the frontal and anterior cingulate regions involved in emotion regulation. Greater response to positive than negative emotional features in these regions also correlated with lower frequencies of economically desirable choices. Our findings suggest that whereas positive emotion regulation involves a reduction of responses in valence representation regions, negative emotion regulation additionally engages brain regions for deliberative processing and signaling of incongruous events.

  3. Financial Incentives Differentially Regulate Neural Processing of Positive and Negative Emotions during Value-Based Decision-Making.

    Science.gov (United States)

    Farrell, Anne M; Goh, Joshua O S; White, Brian J

    2018-01-01

    Emotional and economic incentives often conflict in decision environments. To make economically desirable decisions then, deliberative neural processes must be engaged to regulate automatic emotional reactions. In this functional magnetic resonance imaging (fMRI) study, we evaluated how fixed wage (FW) incentives and performance-based (PB) financial incentives, in which pay is proportional to outcome, differentially regulate positive and negative emotional reactions to hypothetical colleagues that conflicted with the economics of available alternatives. Neural activity from FW to PB incentive contexts decreased for positive emotional stimuli but increased for negative stimuli in middle temporal, insula, and medial prefrontal regions. In addition, PB incentives further induced greater responses to negative than positive emotional decisions in the frontal and anterior cingulate regions involved in emotion regulation. Greater response to positive than negative emotional features in these regions also correlated with lower frequencies of economically desirable choices. Our findings suggest that whereas positive emotion regulation involves a reduction of responses in valence representation regions, negative emotion regulation additionally engages brain regions for deliberative processing and signaling of incongruous events.

  4. Differential mesolimbic and prefrontal alterations during reward anticipation and consummation in positive and negative schizotypy.

    Science.gov (United States)

    Yan, Chao; Wang, Yi; Su, Li; Xu, Ting; Yin, Da-Zhi; Fan, Ming-Xia; Deng, Ci-Ping; Wang, Zhao-Xin; Lui, Simon S Y; Cheung, Eric F C; Chan, Raymond C K

    2016-08-30

    Schizotypy is associated with anhedonia. However, previous findings on the neural substrates of anhedonia in schizotypy are mixed. In the present study, we measured the neural substrates associated with reward anticipation and consummation in positive and negative schizotypy using functional MRI. The Monetary Incentive Delay task was administered to 33 individuals with schizotypy (18 positive schizotypy (PS),15 negative schizotypy (NS)) and 22 healthy controls. Comparison between schizotypy individuals and controls were performed using two-sample T tests for contrast images involving gain versus non-gain anticipation condition and gain versus non-gain consummation condition. Multiple comparisons were corrected using Monte Carlo Simulation correction of panticipation or consummation. However, during the consummatory phase, NS individuals rather than PS individuals showed diminished left amygdala and left putamen activity compared with controls. We observed significantly weaker activation at the left ventral striatum during gain anticipation in NS individuals compared with controls. PS individuals, however, exhibited enhanced right ventral lateral prefrontal activity. These findings suggest that different dimensions of schizotypy may be underlied by different neural dysfunctions in reward anticipation and consummation. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  5. Differentiation of penal policy in the light of positive paradigm and its confronting challenges

    Directory of Open Access Journals (Sweden)

    Bagher Shamlou

    2015-05-01

    Full Text Available Positivism is an empirical approach for understanding of human communication and phenomena, which raised firstly French famous thinker “August Comte”. Human and social Sciences were under domination of positive thought for a long time. In criminal law inter alia Italian famous thinkers sought to analyses the crime problem with a positive approach. However, some of their point of view such as born criminal thesis was not respected by penal scientist, but was affected by their idea was assumed that experiment is the only scientific criterion and basis of criminal law. They thought that value judgments and normative sentences have not scientific character. The positivist approach, developed the abstract thought of classic criminal fundamentalism which was before this, the dominate approach of penal policy towards of objectivism at etiology of crime on the basis of separation of objectivism and subjectivism. But it faced with insufficiency in both methodology and efficiency, so that somebody talked about returning punity approach of classic fundamentalism

  6. Widespread Positive Selection Drives Differentiation of Centromeric Proteins in the Drosophila melanogaster subgroup.

    Science.gov (United States)

    Beck, Emily A; Llopart, Ana

    2015-11-25

    Rapid evolution of centromeric satellite repeats is thought to cause compensatory amino acid evolution in interacting centromere-associated kinetochore proteins. Cid, a protein that mediates kinetochore/centromere interactions, displays particularly high amino acid turnover. Rapid evolution of both Cid and centromeric satellite repeats led us to hypothesize that the apparent compensatory evolution may extend to interacting partners in the Condensin I complex (i.e., SMC2, SMC4, Cap-H, Cap-D2, and Cap-G) and HP1s. Missense mutations in these proteins often result in improper centromere formation and aberrant chromosome segregation, thus selection for maintained function and coevolution among proteins of the complex is likely strong. Here, we report evidence of rapid evolution and recurrent positive selection in seven centromere-associated proteins in species of the Drosophila melanogaster subgroup, and further postulate that positive selection on these proteins could be a result of centromere drive and compensatory changes, with kinetochore proteins competing for optimal spindle attachment.

  7. Aggressiveness, social support and school experiences as dimensions differentiating negative and positive adaptation among adolescents

    Directory of Open Access Journals (Sweden)

    Marzanna Agnieszka Farnicka

    2017-10-01

    Full Text Available Background The study results presented below lie within a field of study which seeks to identify appropriate risk indicators for risky behaviours in the group of adolescents. The study drew on the tenets of developmental psychopathology. Adaptation assessment was performed on the basis of an objective indicator which comprised adolescents’ problems with social functioning. Participants and procedure The main determinants of the observed changes in behaviour and the development of adaptation pathways during the period of adolescence were considered to include bio-psycho-social temperamental factors (Buss & Plomin, 1984, attachment patterns (Armsden & Greenberg, 1987, trait of aggressiveness (Buss & Perry, 1992, conditions created by the environment (support of family members, peers and teachers [Malecki & Demaray, 2002] as well as previous experiences such as being a victim of violence (Osterman & Bjorqvist, 2008 or the level of school success. The final study group comprised a total of 140 positively and 140 negatively adapted teenagers (N = 280 between the ages of 12 and 19. The study was carried out in Poland. Results The study confirmed the gender effect, demonstrating a higher frequency of involvement in risky behaviours among boys. The results from searching for differences between positively and negatively adapted teens showed that in the negatively adapted group there were lower grades at school and more frequent aggressive behaviour. Conclusions The main conclusion that can be drawn from the study is that the potential prophylactic and therapeutic interventions require consideration of factors such as age, educational success, aggressiveness and social support.

  8. Video games: good, bad, or other?

    Science.gov (United States)

    Prot, Sara; McDonald, Katelyn A; Anderson, Craig A; Gentile, Douglas A

    2012-06-01

    Video games are a pervasive pastime among children and adolescents. The growing popularity of video games has instigated a debate among parents, researchers, video game producers, and policymakers concerning potential harmful and helpful effects of video games on children. This article provides an overview of research findings on the positive and negative effects of video games, thus providing an empirical answer to the question, are video games good or bad? The article also provides some guidelines to help pediatricians, parents, and other caregivers protect children from negative effects and to maximize positive effects of video games. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. Job stress, occupational position and gender as factors differentiating workplace bullying experience

    Directory of Open Access Journals (Sweden)

    Marcin Drabek

    2013-06-01

    Full Text Available Background: The results of our research broaden the knowledge concerning the correlates of mobbing. The study is aimed at finding out whether an employee's gender, his/her occupational position and level of occupational stress are related to bullying experience. Material and Methods: 1313 employees of a transport company participated in the study. The relationships between gender, occupational position, the level of stress and bullying were analysed. Bullying was measured by the use of the MDM Questionnaire, while work environment was assessed using the Subjective Assessment of Work Questionnaire. Results: It was found that women were generally more exposed to bullying than men (Z = –1.999; p < 0.05. Women experienced more bullying by their colleagues than men did (Z = –2.712; p < 0.01, in particular: bullying by colleagues that destroys the worker's image (Z = –2.922; p < 0.01 and bullying by colleagues that destroys social relations (Z = –3.004; p < 0.01. Individuals with managerial jobs experienced overall bullying (Z = –2.762; p < 0.01, bullying by colleagues (Z = –0.014; p < 0.05 and bullying by colleagues that destroys social relations (Z = –2.260; p < 0.05 more often than the individuals with non-management positions. The results of the study also indicated that employees with higher level of stress in comparison with less stressed co-workers reported more incidents of bullying behaviour (overall bullying – Z = –8.171; p < 0.001, bullying by colleagues – Z = –7.114; p < 0.001, bullying by supervisors – Z = –6.716; p < 0.001, all types of behaviour – p < 0.001. Conclusions: Comparing the results of our study to the previous research, it seems that the pattern of relationships between individual characteristics and bullying is rooted in the wider cultural context, the specificity of the company, its organisational culture as well as its situation. Therefore it's difficult to talk about irrefutable individual

  10. Brain activities associated with gaming urge of online gaming addiction.

    Science.gov (United States)

    Ko, Chih-Hung; Liu, Gin-Chung; Hsiao, Sigmund; Yen, Ju-Yu; Yang, Ming-Jen; Lin, Wei-Chen; Yen, Cheng-Fang; Chen, Cheng-Sheng

    2009-04-01

    The aim of this study was to identify the neural substrates of online gaming addiction through evaluation of the brain areas associated with the cue-induced gaming urge. Ten participants with online gaming addiction and 10 control subjects without online gaming addiction were tested. They were presented with gaming pictures and the paired mosaic pictures while undergoing functional magnetic resonance imaging (fMRI) scanning. The contrast in blood-oxygen-level dependent (BOLD) signals when viewing gaming pictures and when viewing mosaic pictures was calculated with the SPM2 software to evaluate the brain activations. Right orbitofrontal cortex, right nucleus accumbens, bilateral anterior cingulate and medial frontal cortex, right dorsolateral prefrontal cortex, and right caudate nucleus were activated in the addicted group in contrast to the control group. The activation of the region-of-interest (ROI) defined by the above brain areas was positively correlated with self-reported gaming urge and recalling of gaming experience provoked by the WOW pictures. The results demonstrate that the neural substrate of cue-induced gaming urge/craving in online gaming addiction is similar to that of the cue-induced craving in substance dependence. The above-mentioned brain regions have been reported to contribute to the craving in substance dependence, and here we show that the same areas were involved in online gaming urge/craving. Thus, the results suggest that the gaming urge/craving in online gaming addiction and craving in substance dependence might share the same neurobiological mechanism.

  11. Frequencies of inaudible high-frequency sounds differentially affect brain activity: positive and negative hypersonic effects.

    Directory of Open Access Journals (Sweden)

    Ariko Fukushima

    Full Text Available The hypersonic effect is a phenomenon in which sounds containing significant quantities of non-stationary high-frequency components (HFCs above the human audible range (max. 20 kHz activate the midbrain and diencephalon and evoke various physiological, psychological and behavioral responses. Yet important issues remain unverified, especially the relationship existing between the frequency of HFCs and the emergence of the hypersonic effect. In this study, to investigate the relationship between the hypersonic effect and HFC frequencies, we divided an HFC (above 16 kHz of recorded gamelan music into 12 band components and applied them to subjects along with an audible component (below 16 kHz to observe changes in the alpha2 frequency component (10-13 Hz of spontaneous EEGs measured from centro-parieto-occipital regions (Alpha-2 EEG, which we previously reported as an index of the hypersonic effect. Our results showed reciprocal directional changes in Alpha-2 EEGs depending on the frequency of the HFCs presented with audible low-frequency component (LFC. When an HFC above approximately 32 kHz was applied, Alpha-2 EEG increased significantly compared to when only audible sound was applied (positive hypersonic effect, while, when an HFC below approximately 32 kHz was applied, the Alpha-2 EEG decreased (negative hypersonic effect. These findings suggest that the emergence of the hypersonic effect depends on the frequencies of inaudible HFC.

  12. Differential autoshaping to common and distinctive elements of positive and negative discriminative stimuli.

    Science.gov (United States)

    Wasserman, E A; Anderson, P A

    1974-11-01

    The learning by hungry pigeons of a discrimination between two successively presented compound visual stimuli was investigated using a two-key autoshaping procedure. Common and distinctive stimulus elements were simultaneously presented on separate keys and either followed by food delivery, S+, or not, S-. The subjects acquired both between-trial and within-trial discriminations. On S+ trials, pigeons pecked the distinctive stimulus more than the common stimulus; before responding ceased on S- trials, they pecked the common stimulus more than the distinctive one. Mastery of the within-display discrimination during S+ trials preceded mastery of the between-trials discrimination. These findings extend the Jenkins-Sainsbury analysis of discriminations based upon a single distinguishing feature to discriminations in which common and distinctive elements are associated with both the positive and negative discriminative stimuli. The similarity of these findings to other effects found in autoshaping-approach to signals that forecast reinforcement and withdrawal from signals that forecast nonreinforcement-is also discussed.

  13. Differential autoshaping to common and distinctive elements of positive and negative discriminative stimuli1

    Science.gov (United States)

    Wasserman, Edward A.; Anderson, Patricia A.

    1974-01-01

    The learning by hungry pigeons of a discrimination between two successively presented compound visual stimuli was investigated using a two-key autoshaping procedure. Common and distinctive stimulus elements were simultaneously presented on separate keys and either followed by food delivery, S+, or not, S−. The subjects acquired both between-trial and within-trial discriminations. On S+ trials, pigeons pecked the distinctive stimulus more than the common stimulus; before responding ceased on S− trials, they pecked the common stimulus more than the distinctive one. Mastery of the within-display discrimination during S+ trials preceded mastery of the between-trials discrimination. These findings extend the Jenkins-Sainsbury analysis of discriminations based upon a single distinguishing feature to discriminations in which common and distinctive elements are associated with both the positive and negative discriminative stimuli. The similarity of these findings to other effects found in autoshaping—approach to signals that forecast reinforcement and withdrawal from signals that forecast nonreinforcement—is also discussed. PMID:16811812

  14. Differential positive selection of malaria resistance genes in three indigenous populations of Peninsular Malaysia.

    Science.gov (United States)

    Liu, Xuanyao; Yunus, Yushimah; Lu, Dongsheng; Aghakhanian, Farhang; Saw, Woei-Yuh; Deng, Lian; Ali, Mohammad; Wang, Xu; Nor, Fadzilah Mohd; Ghazali, Fadzilah; Rahman, Thuhairah Abdul; Shaari, Shahrul Azlin; Salleh, Mohd Zaki; Phipps, Maude E; Ong, Rick Twee-Hee; Xu, Shuhua; Teo, Yik-Ying; Hoh, Boon-Peng

    2015-04-01

    The indigenous populations from Peninsular Malaysia, locally known as Orang Asli, continue to adopt an agro-subsistence nomadic lifestyle, residing primarily within natural jungle habitats. Leading a hunter-gatherer lifestyle in a tropical jungle environment, the Orang Asli are routinely exposed to malaria. Here we surveyed the genetic architecture of individuals from four Orang Asli tribes with high-density genotyping across more than 2.5 million polymorphisms. These tribes reside in different geographical locations in Peninsular Malaysia and belong to three main ethno-linguistic groups, where there is minimal interaction between the tribes. We first dissect the genetic diversity and admixture between the tribes and with neighboring urban populations. Later, by implementing five metrics, we investigated the genome-wide signatures for positive natural selection of these Orang Asli, respectively. Finally, we searched for evidence of genomic adaptation to the pressure of malaria infection. We observed that different evolutionary responses might have emerged in the different Orang Asli communities to mitigate malaria infection.

  15. Frequencies of inaudible high-frequency sounds differentially affect brain activity: positive and negative hypersonic effects.

    Science.gov (United States)

    Fukushima, Ariko; Yagi, Reiko; Kawai, Norie; Honda, Manabu; Nishina, Emi; Oohashi, Tsutomu

    2014-01-01

    The hypersonic effect is a phenomenon in which sounds containing significant quantities of non-stationary high-frequency components (HFCs) above the human audible range (max. 20 kHz) activate the midbrain and diencephalon and evoke various physiological, psychological and behavioral responses. Yet important issues remain unverified, especially the relationship existing between the frequency of HFCs and the emergence of the hypersonic effect. In this study, to investigate the relationship between the hypersonic effect and HFC frequencies, we divided an HFC (above 16 kHz) of recorded gamelan music into 12 band components and applied them to subjects along with an audible component (below 16 kHz) to observe changes in the alpha2 frequency component (10-13 Hz) of spontaneous EEGs measured from centro-parieto-occipital regions (Alpha-2 EEG), which we previously reported as an index of the hypersonic effect. Our results showed reciprocal directional changes in Alpha-2 EEGs depending on the frequency of the HFCs presented with audible low-frequency component (LFC). When an HFC above approximately 32 kHz was applied, Alpha-2 EEG increased significantly compared to when only audible sound was applied (positive hypersonic effect), while, when an HFC below approximately 32 kHz was applied, the Alpha-2 EEG decreased (negative hypersonic effect). These findings suggest that the emergence of the hypersonic effect depends on the frequencies of inaudible HFC.

  16. Multiple positive solutions to nonlinear boundary value problems of a system for fractional differential equations.

    Science.gov (United States)

    Zhai, Chengbo; Hao, Mengru

    2014-01-01

    By using Krasnoselskii's fixed point theorem, we study the existence of at least one or two positive solutions to a system of fractional boundary value problems given by -D(0+)(ν1)y1(t) = λ1a1(t)f(y1(t), y2(t)), - D(0+)(ν2)y2(t) = λ2a2(t)g(y1(t), y2(t)), where D(0+)(ν) is the standard Riemann-Liouville fractional derivative, ν1, ν2 ∈ (n - 1, n] for n > 3 and n ∈ N, subject to the boundary conditions y1((i))(0) = 0 = y ((i))(0), for 0 ≤ i ≤ n - 2, and [D(0+)(α)y1(t)] t=1 = 0 = [D(0+ (α)y2(t)] t=1, for 1 ≤ α ≤ n - 2, or y1((i))(0) = 0 = y ((i))(0), for 0 ≤ i ≤ n - 2, and [D(0+)(α)y1(t)] t=1 = ϕ1(y1), [D(0+)(α)y2(t)] t=1 = ϕ2(y2), for 1 ≤ α ≤ n - 2, ϕ1, ϕ2 ∈ C([0,1], R). Our results are new and complement previously known results. As an application, we also give an example to demonstrate our result.

  17. Personalised gaming

    NARCIS (Netherlands)

    Bakkes, S.; Tan, C.T.; Pisan, Y.

    2012-01-01

    This article focuses on personalised games, which we define as games that utilise player models for the purpose of tailoring the game experience to the individual player. The main contribution of the article is a motivation for personalised gaming, supported by an extensive overview of scientific

  18. Game Studies

    NARCIS (Netherlands)

    Raessens, J.F.F.

    2016-01-01

    This entry describes game studies as a dynamic interdisciplinary field of academic study and research that focuses on digital games and play in a wide variety of social and cultural contexts. It examines the history of game studies from its prehistory, when games were looked at as part of other

  19. Game theory

    DEFF Research Database (Denmark)

    Hendricks, Vincent F.

    Game Theory is a collection of short interviews based on 5 questions presented to some of the most influential and prominent scholars in game theory. We hear their views on game theory, its aim, scope, use, the future direction of game theory and how their work fits in these respects....

  20. Technology: Learning Can Be Fun and Games

    Science.gov (United States)

    Siegle, Del

    2015-01-01

    Video games can provide cognitive, motivational, emotional, and social benefits to students when properly implemented in the classroom. Teachers who are well versed in their curriculum can use games to differentiate instruction for gifted and talented students. This article discusses the benefits of gaming in education settings and provides…

  1. On the extreme points of the core of neighbour games and assignment games

    NARCIS (Netherlands)

    Hamers, H.J.M.; Klijn, F.; Solymosi, T.; Tijs, S.H.; Pere Villar, J.

    1999-01-01

    Neighbour games arise from certain matching or sequencing situations in which only some specific pairs of players can obtain a positive gain. As a consequence, neighbour games are as well assignment games as line graph restricted games. We will show that the intersection of the class of assignment

  2. A Systematic Literature Review of Empirical Evidence on Computer Games and Serious Games

    Science.gov (United States)

    Connolly, Thomas M.; Boyle, Elizabeth A.; MacArthur, Ewan; Hainey, Thomas; Boyle, James M.

    2012-01-01

    This paper examines the literature on computer games and serious games in regard to the potential positive impacts of gaming on users aged 14 years or above, especially with respect to learning, skill enhancement and engagement. Search terms identified 129 papers reporting empirical evidence about the impacts and outcomes of computer games and…

  3. Stochastic Game Approach to Guidance Design

    Science.gov (United States)

    1988-09-09

    maneuverable aircraft, which can employ also electronic counter measures, is formulated as an imper- fect information zero-sum pursuit-evasion game played...on Differential Game Applications [36]. However, some other examples which included " electronic jinking", indicated that in an ECM environment a mixed...radius, b) missile/target maneuver ratio, c) nonlinear maneuver similarity parameter (aE T2 max d) normalized end- game duration, e ) ini’tial end- game

  4. Top Differential Diagnosis Should Be Microscopic Polyangiitis in ANCA-Positive Patient with Diffuse Pulmonary Hemorrhage and Hemosiderosis

    Directory of Open Access Journals (Sweden)

    Nicholas D. Ward

    2014-01-01

    Full Text Available A rat model of antineutrophil cytoplasmic antibody (ANCA associated vasculitides reveals crescentic glomerulonephritis as seen in human renal biopsies and diffuse lung hemorrhage that is not well documented in human lung biopsies. A 64-year-old male, with shortness of breath and mild elevation of serum creatinine, was found to have a positive serum test for ANCA, but negative antiglomerular basement membrane antibody. A renal biopsy showed pauci-immune type of crescentic glomerulonephritis and focal arteritis. The prior lung wedge biopsy was retrospectively reviewed to show diffuse hemorrhage and hemosiderosis with focal giant cells. In addition, small arteries revealed subtle neutrophil aggregation, and margination along vascular endothelium, but no definitive vasculitis. The pathology of ANCA associated vasculitides results from activated neutrophils by ANCA and subsequent activation of the alternative complement cascade with endothelial injury, neutrophil aggregation and margination. Our findings, after the correlation between lung biopsy and renal biopsy, imply that the top differential diagnosis in the lung biopsy should be microscopic polyangiitis when diffuse pulmonary hemorrhage and hemosiderosis are present in this ANCA-positive patient.

  5. The Association Between Video Game Play and Cognitive Function: Does Gaming Platform Matter?

    Science.gov (United States)

    Huang, Vivian; Young, Michaelia; Fiocco, Alexandra J

    2017-11-01

    Despite consumer growth, few studies have evaluated the cognitive effects of gaming using mobile devices. This study examined the association between video game play platform and cognitive performance. Furthermore, the differential effect of video game genre (action versus nonaction) was explored. Sixty undergraduate students completed a video game experience questionnaire, and we divided them into three groups: mobile video game players (MVGPs), console/computer video game players (CVGPs), and nonvideo game players (NVGPs). Participants completed a cognitive battery to assess executive function, and learning and memory. Controlling for sex and ethnicity, analyses showed that frequent video game play is associated with enhanced executive function, but not learning and memory. MVGPs were significantly more accurate on working memory performances than NVGPs. Both MVGPs and CVGPs were similarly associated with enhanced cognitive function, suggesting that platform does not significantly determine the benefits of frequent video game play. Video game platform was found to differentially associate with preference for action video game genre and motivation for gaming. Exploratory analyses show that sex significantly effects frequent video game play, platform and genre preference, and cognitive function. This study represents a novel exploration of the relationship between mobile video game play and cognition and adds support to the cognitive benefits of frequent video game play.

  6. Writerly Gaming: Political Gaming

    DEFF Research Database (Denmark)

    Andersen, Christian Ulrik

    2007-01-01

    software for private entertainment (looking/feeling real) or they can be pragmatic software used for training of professionals (affecting soldiers’, pilots’, etc. perception of the real). A third, and less debated game-reality relationship, based on public awareness and typically a socio-political agenda...

  7. Central line-associated bloodstream infections in adult hematology patients with febrile neutropenia: an evaluation of surveillance definitions using differential time to blood culture positivity.

    Science.gov (United States)

    Freeman, Joshua T; Elinder-Camburn, Anna; McClymont, Catherine; Anderson, Deverick J; Bilkey, Mary; Williamson, Deborah A; Berkahn, Leanne; Roberts, Sally A

    2013-01-01

    We used differential time to positivity between central and peripheral blood cultures to evaluate the positive predictive value (PPV) of the National Healthcare Safety Network central line-associated bloodstream infection (CLABSI) surveillance definition among hematology patients with febrile neutropenia. The PPV was 27.7%, which suggests that, when the definition is applied to this population, CLABSI rates will be substantially overestimated.

  8. Failure to differentiate between threat-related and positive emotion cues in healthy adults with childhood interpersonal or adult trauma.

    Science.gov (United States)

    Chu, Denise A; Bryant, Richard A; Gatt, Justine M; Harris, Anthony W F

    2016-07-01

    Enhanced threat-related processing is associated with both elevated anxiety and childhood exposure to trauma. Given the paucity of evidence regarding the effects of childhood and adult trauma exposure on subsequent psychophysiological processes in the absence of psychopathology, we investigated the relative impacts of childhood interpersonal and non-interpersonal trauma, as well as adult trauma exposure on neural processing of threat in healthy adults. We measured peak amplitudes of the N170 face-sensitive visual ERP component response to non-conscious and conscious Angry (threat) versus Happy (non-threat, positive) and Neutral (non-threat baseline) faces at temporo-occipital sites (right-T6; left-T5) in 489 psychiatrically asymptomatic adults (aged 18-70 years, 54% women, 94% right-handed). N170 peak amplitude differences between Angry vs Happy or Neutral faces were calculated and subjected to hierarchical multiple regression analysis, with trauma types (childhood interpersonal, childhood non-interpersonal and adult trauma) entered as predictors of interest. After controlling for sociodemographic and health factors, N170 peak amplitudes for non-conscious Angry vs Happy faces were inversely associated with childhood interpersonal trauma at T6 and adult trauma exposure at T5. Post-hoc repeated measures ANOVA indicated that unlike adults without trauma exposure, trauma-exposed adults failed to show significantly reduced N170 responses to Happy relative to Angry faces during non-conscious processing. This suggests that childhood interpersonal and adult trauma exposure are associated with a failure to differentiate between non-threat or positive and threat-related emotion cues. This is consistent with generalised hypervigilance seen in PTSD, and suggests trauma exposure is associated with a generalized heightened responsivity to non-conscious non-threat or positive as well as threat-related emotion cues in psychiatrically healthy adults. Copyright © 2016 Elsevier Ltd

  9. Quantum Bertrand duopoly with differentiated products

    International Nuclear Information System (INIS)

    Lo, C.F.; Kiang, D.

    2004-01-01

    We apply Li et al.'s 'minimal' quantization rules [Phys. Lett. A 306 (2002) 73] to investigate the quantum version of the Bertrand duopoly with differentiated products. In particular, we have examined how the quantum entanglement affects the outcome of the classical game. It is found that while negative entanglement diminishes the profit of each firm below the classical limit, positive entanglement enhances the profit monotonically, reaching a maximum in the limit of maximal entanglement. As a consequence, the frustrating dilemma-like situation is completely resolved in the quantum version of the game

  10. Creating Evaluation Profiles for Games Designed to be Fun: An Interpretive Framework for Serious Game Mechanics

    DEFF Research Database (Denmark)

    Ulrich, Frank; Helms, Niels Henrik

    2017-01-01

    Background. Games can be great pedagogical tools for educators and students. COTS games (commercialoff-the-shelf) are designed for the pure purpose of leisure but can also contain educational value. Aim. In this paper, we address the potential of COTS games as serious games. We develop...... an interpretive evaluation framework that can identify the educational value in COTS games. Application. The presented framework can create evaluative profiles of the learning, social, game, and immersive mechanics of COTS games as educational tools. Moreover, the framework can position COTS games between four...... enables critical reflection on the game mechanics; thereby capturing the complexity of the game mechanics that makes COTS game both educational and fun to play....

  11. Social activities, self-efficacy, game attitudes, and game addiction.

    Science.gov (United States)

    Jeong, Eui Jun; Kim, Doo Hwan

    2011-04-01

    This study examines whether social activities with parents, online and offline social self-efficacy, and attitudes toward gaming are associated with the degree of game addiction among adolescents. Using data from a survey of 600 middle- and high-school students in South Korea, we tested the relationships of personal characteristics (grade point average and time spent on gaming each day), social self-efficacy (both on- and offline), general social activities (with parents, friends, and teachers), gaming activities with parents, and attitudes toward gaming (those of self, parents, friends, and teachers) with the degree of game addiction. In addition, we conducted ANOVA tests to determine the differences among three groups: non-addicts (NA), possible (mild or moderate) addicts (PA), and Internet addicts (IA). The results show that social self-efficacy in the real world (offline) was negatively related with the degree of game addiction, whereas social self-efficacy in the virtual world (online) indicated a positive association. Social activities with parents are negatively associated with game addiction, although no relationship is found between gaming activities with parents and game addiction. Parental attitude toward gaming has a negative relationship with the addiction. Results and implications are discussed.

  12. Altered Brain Reactivity to Game Cues After Gaming Experience.

    Science.gov (United States)

    Ahn, Hyeon Min; Chung, Hwan Jun; Kim, Sang Hee

    2015-08-01

    Individuals who play Internet games excessively show elevated brain reactivity to game-related cues. This study attempted to test whether this elevated cue reactivity observed in game players is a result of repeated exposure to Internet games. Healthy young adults without a history of excessively playing Internet games were recruited, and they were instructed to play an online Internet game for 2 hours/day for five consecutive weekdays. Two control groups were used: the drama group, which viewed a fantasy TV drama, and the no-exposure group, which received no systematic exposure. All participants performed a cue reactivity task with game, drama, and neutral cues in the brain scanner, both before and after the exposure sessions. The game group showed an increased reactivity to game cues in the right ventrolateral prefrontal cortex (VLPFC). The degree of VLPFC activation increase was positively correlated with the self-reported increase in desire for the game. The drama group showed an increased cue reactivity in response to the presentation of drama cues in the caudate, posterior cingulate, and precuneus. The results indicate that exposure to either Internet games or TV dramas elevates the reactivity to visual cues associated with the particular exposure. The exact elevation patterns, however, appear to differ depending on the type of media experienced. How changes in each of the regions contribute to the progression to pathological craving warrants a future longitudinal study.

  13. (ludo) game

    African Journals Online (AJOL)

    Dr Obe

    participants make decisions with or without the intervention of ... formulation of game theory started in 1944 with the publication of the book ... Nearly all games require seeing patterns, making plans, searching ..... utility/ outcome. •. Players will ...

  14. [Game addiction].

    Science.gov (United States)

    Mori, Akio; Iwadate, Masako; Minakawa, Nahoko T; Kawashima, Satoshi

    2015-09-01

    The purpose of this article is to analyze the South Korea and China of computer game research, and the current state of research in Japan. Excessive game actions were analyzed by PET-MRI, MRI, fMRI, NIRS, EEG. These results showed that the prefrontal cortical activity decreased during game play. Also, game addiction causes damage to the prefrontal cortex. The NIRS-EEG and simultaneous recording, during game play correspond well with the decrease of β band and oxygen-hemoglobin. The α band did not change with game play. However, oxygen-hemoglobin decreased during game play. South Korea, game addiction measures have been analyzed since 2002, but in Japan the research is recent.

  15. Casual Games

    DEFF Research Database (Denmark)

    Hansen, Ole Ertløv

    2015-01-01

    Casual games have become a widespread activity that fills our leisure time. This article introduces to the phenomenon casual games – their definition and the history. Furthermore the article presents and discusses the experience of and engagement or immersion in playing these games as it is put...... forward by recent research. The theoretical approach is based on media psychology, phenomenology and reversal theory. Finally it is argued that playing casual games is fundamental pleasurable to both paratelic as well as telic metamotivational states....

  16. Game Spaces

    DEFF Research Database (Denmark)

    Kristiansen, Erik

    2015-01-01

    , called “pervasive games.” These are games that are based on computer technology, but use a physical space as the game space as opposed to video games. Coupling spatial configuration with performance theory of rituals as liminal phenomena, I put forward a model and a new understanding of the magic circle......When we play games of any kind, from tennis to board games, it is easy to notice that games seem to be configured in space, often using stripes or a kind of map on a board. Some games are clearly performed within this marked border, while it may be difficult to pinpoint such a border in games like...... hide-and-seek, but even these games are still spatially configured. The border (visible or not) both seem to separate and uphold the game that it is meant for. This chapter sets out to analyse the possible border that separates a game from the surrounding world. Johan Huizinga noted this “separateness...

  17. Ground penetrating radar and differential global positioning system data collected in April 2016 from Fire Island, New York

    Science.gov (United States)

    Forde, Arnell S.; Bernier, Julie C.; Miselis, Jennifer L.

    2018-02-22

    Researchers from the U.S. Geological Survey (USGS) conducted a long-term coastal morphologic-change study at Fire Island, New York, prior to and after Hurricane Sandy impacted the area in October 2012. The Fire Island Coastal Change project objectives include understanding the morphologic evolution of the barrier island system on a variety of time scales (months to centuries) and resolving storm-related impacts, post-storm beach response, and recovery. In April 2016, scientists from the USGS St. Petersburg Coastal and Marine Science Center conducted geophysical and sediment sampling surveys on Fire Island to characterize and quantify spatial variability in the subaerial geology with the goal of subsequently integrating onshore geology with other surf zone and nearshore datasets.  This report, along with the associated USGS data release, serves as an archive of ground penetrating radar (GPR) and post-processed differential global positioning system (DGPS) data collected from beach and back-barrier environments on Fire Island, April 6–13, 2016 (USGS Field Activity Number 2016-322-FA). Data products, including unprocessed GPR trace data, processed DGPS data, elevation-corrected subsurface profile images, geographic information system files, and accompanying Federal Geographic Data Committee metadata are available for download.

  18. Game theory.

    Science.gov (United States)

    Dufwenberg, Martin

    2011-03-01

    Game theory is a toolkit for examining situations where decision makers influence each other. I discuss the nature of game-theoretic analysis, the history of game theory, why game theory is useful for understanding human psychology, and why game theory has played a key role in the recent explosion of interest in the field of behavioral economics. WIREs Cogni Sci 2011 2 167-173 DOI: 10.1002/wcs.119 For further resources related to this article, please visit the WIREs website. Copyright © 2010 John Wiley & Sons, Ltd.

  19. Game injuries in relation to game schedules in the National Basketball Association.

    Science.gov (United States)

    Teramoto, Masaru; Cross, Chad L; Cushman, Daniel M; Maak, Travis G; Petron, David J; Willick, Stuart E

    2017-03-01

    Injury management is critical in the National Basketball Association (NBA), as players experience a wide variety of injuries. Recently, it has been suggested that game schedules, such as back-to-back games and four games in five days, increase the risk of injuries in the NBA. The aim of this study was to examine the association between game schedules and player injuries in the NBA. Descriptive epidemiology study. The present study analyzed game injuries and game schedules in the 2012-13 through 2014-15 regular seasons. Game injuries by game schedules and players' profiles were examined using an exact binomial test, the Fisher's exact test and the Mann-Whitney-Wilcoxon test. A Poisson regression analysis was performed to predict the number of game injuries sustained by each player from game schedules and injured players' profiles. There were a total of 681 cases of game injuries sustained by 280 different players during the three years (total N=1443 players). Playing back-to-back games or playing four games in five days alone was not associated with an increased rate of game injuries, whereas a significant positive association was found between game injuries and playing away from home (pNBA. The findings could be useful for designing optimal game schedules in the NBA as well as helping NBA teams make adjustments to minimize game injuries. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  20. Authoring of Adaptive Single-Player Educational Games

    OpenAIRE

    Mehm, Florian

    2013-01-01

    Digital Educational Games, as one of the most important application areas of Serious Games, combine positive properties of digital games, such as strong motivation for players and inherent learning processes, with educational methods and technologies. Adaptive algorithms allow such games to be aligned automatically to the needs of different players, thereby increasing the learning efficacy. However, educational games are among the most complex game production endeavors, since they are often f...

  1. Intense video gaming is not essentially problematic.

    Science.gov (United States)

    Király, Orsolya; Tóth, Dénes; Urbán, Róbert; Demetrovics, Zsolt; Maraz, Aniko

    2017-11-01

    Video games are more popular than ever and the general public, including parents, educators, and the media, tends to consider intense video gaming fundamentally problematic. To test this hypothesis, participants were recruited via gaming-related websites resulting in a sample of N = 5,222 online video gamers (mean age: 22.2 years, SD = 6.4). Besides assessing gaming time, we administered the Ten-Item Internet Gaming Disorder Test, the Brief Symptom Inventory, and the Motives for Online Gaming Questionnaire. Two structural regression models were estimated with both gaming time and problematic gaming as outcome variables. Predictors were psychiatric symptoms in the first, and gaming motives in the second model. Both models yielded adequate fit indices. Psychiatric symptoms had a moderate positive effect on problematic use (β = .46, p gaming time was practically zero (β = -.01, p = .84). In the second model, Escape was the most prominent motive and was moderately to-strongly associated (β = .58, p gaming time was substantially weaker (β = .21, p gaming time and problematic use was weak-to-moderate in both models (r = .26, p gaming time is weakly associated with negative psychological factors such as psychiatric symptoms and Escape motive, which were found to be consistently related to problematic use. Therefore, the amount of gaming time alone appears to be an unreliable predictor of problematic use, which questions the aforementioned idea that intense gaming is essentially problematic. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  2. Game and Digital Culture: A Study on Hay Day Game

    Directory of Open Access Journals (Sweden)

    Mia Angeline

    2016-01-01

    Full Text Available Digital games are a commercial product developed and distributed by media companies and often uses characters or scenarios of movies, books, and comics. The digital game play comes from individual media consumption patterns. Playing digital games also offer experience and satisfaction based on interactive communication technologies and immersive gameplay. In this digital age, digital games became more social-based, which means they implement the need to invite friends on social media to come into play and help each other in the game. The problems of this study was to determine what factors make Hay Day popular among the players and to find out how Hay Day changing the social patterns interaction of the players. This study aims to look at the functions of digital games in the context of communication with relations in social media and why certain games can achieve very high popularity, while other games failed miserably. This research focuses on Hay Day. The method used is descriptive qualitative approach with case study method. Data collection is using interviews with players active in the game, as well as observation and literature studies. The results showed that a game may gain popularity if someone has a social media environment prior to play. Interactive concept, simulation, and fantasy game technology are also the reason Hay Day became very popular. The perception that the digital game player who formerly regarded as anti-social experience has shifted in the concept of digital game-based social bookmark. Players who have a lot of friends in games are seen as someone who has a lot of friends and a high social level. This is in line with the functions of a traditional game in Indonesian culture, where the region has a wide variety of games to be played together and motivate positive social interaction. Function of digital games also increased, other than playing the game as entertainment, but also now the game became one of the effective

  3. Virtual Cinematography in Games

    DEFF Research Database (Denmark)

    Burelli, Paolo

    2013-01-01

    Cinematography is a key aspect in the development of modern computer games. The quality of the visuals depends, not only on the accuracy of the rendering, but on the way that the scene is presented to the player. Which element should be included in the frame, from which point of view and in which...... positions are all aspects that have been widely stud- ied in classical cinematography. However, it is still unclear how the principles developed for the film medium are ap- plicable to an interactive medium such as computer games. This article presents a study, which explores the interplay between...... cinematography and player experience. The results of the experiment demonstrate the existence of an impact of the cinematographic behaviour of camera on both player’s affect and her in-game behaviour. Furthermore, this impact is dependent on the game mechanics highlighting once more the difference between...

  4. Brains on video games.

    Science.gov (United States)

    Bavelier, Daphne; Green, C Shawn; Han, Doug Hyun; Renshaw, Perry F; Merzenich, Michael M; Gentile, Douglas A

    2011-11-18

    The popular press is replete with stories about the effects of video and computer games on the brain. Sensationalist headlines claiming that video games 'damage the brain' or 'boost brain power' do not do justice to the complexities and limitations of the studies involved, and create a confusing overall picture about the effects of gaming on the brain. Here, six experts in the field shed light on our current understanding of the positive and negative ways in which playing video games can affect cognition and behaviour, and explain how this knowledge can be harnessed for educational and rehabilitation purposes. As research in this area is still in its early days, the contributors of this Viewpoint also discuss several issues and challenges that should be addressed to move the field forward.

  5. Co-occurrence of addictive behaviours: personality factors related to substance use, gambling and computer gaming.

    Science.gov (United States)

    Walther, Birte; Morgenstern, Matthis; Hanewinkel, Reiner

    2012-01-01

    To investigate co-occurrence and shared personality characteristics of problematic computer gaming, problematic gambling and substance use. Cross-sectional survey data were collected from 2,553 German students aged 12-25 years. Self-report measures of substance use (alcohol, tobacco and cannabis), problematic gambling (South Oaks Gambling Screen - Revised for Adolescents, SOGS-RA), problematic computer gaming (Video Game Dependency Scale, KFN-CSAS-II), and of twelve different personality characteristics were obtained. Analyses revealed positive correlations between tobacco, alcohol and cannabis use and a smaller positive correlation between problematic gambling and problematic computer gaming. Problematic computer gaming co-occurred only with cannabis use, whereas problematic gambling was associated with all three types of substance use. Multivariate multilevel analyses showed differential patterns of personality characteristics. High impulsivity was the only personality characteristic associated with all five addictive behaviours. Depression and extraversion were specific to substance users. Four personality characteristics were specifically associated with problematic computer gaming: irritability/aggression, social anxiety, ADHD, and low self-esteem. Problematic gamblers seem to be more similar to substance users than problematic computer gamers. From a personality perspective, results correspond to the inclusion of gambling in the same DSM-V category as substance use and question a one-to-one proceeding for computer gaming. Copyright © 2012 S. Karger AG, Basel.

  6. Modeling the Smartphone Game to Improve Players Focus Case Study of Game Dumb Ways to Die

    Directory of Open Access Journals (Sweden)

    Elisa Purnamasari

    2014-10-01

    There are a need to find some characteristics of a game which has positive effects for the players. Those characteristics can be formulated as the example of a good game. This paper will analyze the opinion and produce the conclusion from a survey of playing "Dumb Ways to Die to generate a positive game model.

  7. Personal, social, and game-related correlates of active and non-active gaming among dutch gaming adolescents: survey-based multivariable, multilevel logistic regression analyses.

    Science.gov (United States)

    Simons, Monique; de Vet, Emely; Chinapaw, Mai Jm; de Boer, Michiel; Seidell, Jacob C; Brug, Johannes

    2014-04-04

    Playing video games contributes substantially to sedentary behavior in youth. A new generation of video games-active games-seems to be a promising alternative to sedentary games to promote physical activity and reduce sedentary behavior. At this time, little is known about correlates of active and non-active gaming among adolescents. The objective of this study was to examine potential personal, social, and game-related correlates of both active and non-active gaming in adolescents. A survey assessing game behavior and potential personal, social, and game-related correlates was conducted among adolescents (12-16 years, N=353) recruited via schools. Multivariable, multilevel logistic regression analyses, adjusted for demographics (age, sex and educational level of adolescents), were conducted to examine personal, social, and game-related correlates of active gaming ≥1 hour per week (h/wk) and non-active gaming >7 h/wk. Active gaming ≥1 h/wk was significantly associated with a more positive attitude toward active gaming (OR 5.3, CI 2.4-11.8; Pgames (OR 0.30, CI 0.1-0.6; P=.002), a higher score on habit strength regarding gaming (OR 1.9, CI 1.2-3.2; P=.008) and having brothers/sisters (OR 6.7, CI 2.6-17.1; Pgame engagement (OR 0.95, CI 0.91-0.997; P=.04). Non-active gaming >7 h/wk was significantly associated with a more positive attitude toward non-active gaming (OR 2.6, CI 1.1-6.3; P=.035), a stronger habit regarding gaming (OR 3.0, CI 1.7-5.3; P7 h/wk. Active gaming is most strongly (negatively) associated with attitude with respect to non-active games, followed by observed active game behavior of brothers and sisters and attitude with respect to active gaming (positive associations). On the other hand, non-active gaming is most strongly associated with observed non-active game behavior of friends, habit strength regarding gaming and attitude toward non-active gaming (positive associations). Habit strength was a correlate of both active and non-active gaming

  8. Differential Learning as a Key Training Approach to Improve Creative and Tactical Behavior in Soccer.

    Science.gov (United States)

    Santos, Sara; Coutinho, Diogo; Gonçalves, Bruno; Schöllhorn, Wolfgang; Sampaio, Jaime; Leite, Nuno

    2018-03-01

    The aim of this study was to identify the effects of a differential-learning program, embedded in small-sided games, on the creative and tactical behavior of youth soccer players. Forty players from under-13 (U13) and under-15 (U15) were allocated into control and experimental groups and were tested using a randomized pretest to posttest design using small-sided games situations. The experimental group participated in a 5-month differential-learning program embodied in small-sided games situations, while the control group participated in a typical small-sided games training program. In-game creativity was assessed through notational analyses of the creative components, and the players' positional data were used to compute tactical-derived variables. The findings suggested that differential learning facilitated the development of creative components, mainly concerning attempts (U13, small; U15, small), versatility (U13, moderate; U15, small), and originality (U13, unclear; U15, small) of players' actions. Likewise, the differential-learning approach provided a decrease in fails during the game in both experimental groups (moderate). Moreover, differential learning seemed to favor regularity in pitch-positioning behavior for the distance between players' dyads (U13, small; U15, small), the distance to the team target (U13, moderate; U15, small), and the distance to the opponent target (U13, moderate; U15, small). The differential-learning program stressed creative and positional behavior in both age groups with a distinct magnitude of effects, with the U13 players demonstrating higher improvements over the U15 players. Overall, these findings confirmed that the technical variability promoted by differential learning nurtures regularity of positioning behavior.

  9. How we see electronic games

    Science.gov (United States)

    Weinstein, Netta

    2016-01-01

    Theories regarding the influences of electronic games drive scientific study, popular debate, and public policy. The fractious interchanges among parents, pundits, and scholars hint at the rich phenomenological and psychological dynamics that underlie how people view digital technologies such as games. The current research applied Martin Heidegger’s concept of interpretive frameworks (Heidegger, 1987) and Robert Zajonc’s exposure-attitude hypothesis (Zajonc, 1968) to explore how attitudes towards technologies such as electronic games arise. Three studies drew on representative cohorts of American and British adults and evaluated how direct and indirect experiences with games shape how they are seen. Results indicated this approach was fruitful: negative attitudes and beliefs linking games to real-world violence were prominent among those with little direct exposure to electronic gaming contexts, whereas those who played games and reported doing so with their children tended to evaluate gaming more positively. Further findings indicated direct experience tended to inform the accuracy of beliefs about the effects of digital technology, as those who had played were more likely to believe that which is empirically known about game effects. Results are discussed with respect to ongoing debates regarding gaming and broader applications of this approach to understand the psychological dynamics of adapting to technological advances. PMID:27077016

  10. How we see electronic games

    Directory of Open Access Journals (Sweden)

    Andrew K. Przybylski

    2016-04-01

    Full Text Available Theories regarding the influences of electronic games drive scientific study, popular debate, and public policy. The fractious interchanges among parents, pundits, and scholars hint at the rich phenomenological and psychological dynamics that underlie how people view digital technologies such as games. The current research applied Martin Heidegger’s concept of interpretive frameworks (Heidegger, 1987 and Robert Zajonc’s exposure-attitude hypothesis (Zajonc, 1968 to explore how attitudes towards technologies such as electronic games arise. Three studies drew on representative cohorts of American and British adults and evaluated how direct and indirect experiences with games shape how they are seen. Results indicated this approach was fruitful: negative attitudes and beliefs linking games to real-world violence were prominent among those with little direct exposure to electronic gaming contexts, whereas those who played games and reported doing so with their children tended to evaluate gaming more positively. Further findings indicated direct experience tended to inform the accuracy of beliefs about the effects of digital technology, as those who had played were more likely to believe that which is empirically known about game effects. Results are discussed with respect to ongoing debates regarding gaming and broader applications of this approach to understand the psychological dynamics of adapting to technological advances.

  11. How we see electronic games.

    Science.gov (United States)

    Przybylski, Andrew K; Weinstein, Netta

    2016-01-01

    Theories regarding the influences of electronic games drive scientific study, popular debate, and public policy. The fractious interchanges among parents, pundits, and scholars hint at the rich phenomenological and psychological dynamics that underlie how people view digital technologies such as games. The current research applied Martin Heidegger's concept of interpretive frameworks (Heidegger, 1987) and Robert Zajonc's exposure-attitude hypothesis (Zajonc, 1968) to explore how attitudes towards technologies such as electronic games arise. Three studies drew on representative cohorts of American and British adults and evaluated how direct and indirect experiences with games shape how they are seen. Results indicated this approach was fruitful: negative attitudes and beliefs linking games to real-world violence were prominent among those with little direct exposure to electronic gaming contexts, whereas those who played games and reported doing so with their children tended to evaluate gaming more positively. Further findings indicated direct experience tended to inform the accuracy of beliefs about the effects of digital technology, as those who had played were more likely to believe that which is empirically known about game effects. Results are discussed with respect to ongoing debates regarding gaming and broader applications of this approach to understand the psychological dynamics of adapting to technological advances.

  12. Simulation games

    OpenAIRE

    Giddings, S.

    2013-01-01

    This chapter outlines the conventions and pleasures of simulation games as a category, and explores the complicated and contested term simulation. This concept goes to the heart of what computer games and video games are, and the ways in which they articulate ideas, processes, and phenomena between their virtual worlds and the actual world. It has been argued that simulations generate and communicate knowledge and events quite differently from the long-­dominant cultural mode of narrative. Th...

  13. Game physics

    CERN Document Server

    Eberly, David H

    2010-01-01

    ""Game Physics, 2nd Edition"" provides clear descriptions of the mathematics and algorithms needed to create a powerful physics engine - while providing a solid reference for all of the math you will encounter anywhere in game development: quaternions, linear algebra, and calculus. Implementing physical simulations for real-time games is a complex task that requires a solid understanding of a wide range of concepts from the fields of mathematics and physics. Previously, the relevant information could only be gleaned through obscure research papers. Thanks to ""Game Physics"", all this informa

  14. Serious Games

    DEFF Research Database (Denmark)

    Andersen, Christian Ulrik

    2006-01-01

    T hese days one of the buzzwords in computer game industry and research is ‘Serious Games’ – games where the actions of the player are not limited to the virtual world but are somehow related to the real world. Computer games can be strong environments for learning and training skills in the real...... world. Computer games can also be persuasive – they can be used for advertising (‘adver-gaming’) and induce the players to buy a particular product in the real world or they can propagate a particular political viewpoint or a critique of the real world. The area of ‘serious gaming’ is vast and varied....

  15. Design Games

    DEFF Research Database (Denmark)

    Johansson, Martin Wetterstrand

    2007-01-01

    In this paper design games are discussed as an approach to managing design sessions. The focus is on the collaborative design session and more particular on how to set up the collaboration and reinsure progress. Design games have the advantage of framing the collaborative assignment at hand....... Experiments can be set up to explore possible futures and design games has the qualities of elegantly focus the work at the same time as it lessens the burden for the process facilitator. The present paper goes into detail about how design games can be set up to facilitate collaboration and how the design...

  16. Video games

    OpenAIRE

    Kolář, Vojtěch

    2012-01-01

    This thesis is based on a detailed analysis of various topics related to the question of whether video games can be art. In the first place it analyzes the current academic discussion on this subject and confronts different opinions of both supporters and objectors of the idea, that video games can be a full-fledged art form. The second point of this paper is to analyze the properties, that are inherent to video games, in order to find the reason, why cultural elite considers video games as i...

  17. TRANSGENIC GDNF POSITIVELY INFLUENCES PROLIFERATION, DIFFERENTIATION, MATURATION AND SURVIVAL OF MOTOR NEURONS PRODUCED FROM MOUSE EMBRYONIC STEM CELLS.

    Directory of Open Access Journals (Sweden)

    Daniel Édgar Cortés

    2016-09-01

    Full Text Available Embryonic stem cells (ESC are pluripotent and thus can differentiate into every cell type present in the body. Directed differentiation into motor neurons has been described for pluripotent cells. Although neurotrophic factors promote neuronal survival, their role in neuronal commitment is elusive. Here, we developed double-transgenic lines of mouse ESC that constitutively produce Glial cell-derived neurotrophic factor (GDNF and also contain a GFP reporter, driven by HB9, which is expressed only by postmitotic motor neurons. After lentiviral transduction, ESC lines integrated and expressed the human GDNF gene without altering pluripotency markers before differentiation. Further, GDNF-ESC showed significantly higher spontaneous release of this neurotrophin to the medium, when compared to controls. To study motor neuron induction, control and GDNF cell lines were grown as embryoid bodies and stimulated with retinoic acid and Sonic Hedgehog. In GDNF-overexpressing cells, a significant increase of proliferative Olig2+ precursors, which are specified as spinal motor neurons, was found. Accordingly, GDNF increases the yield of cells with the pan motor neuronal markers HB9, monitored by GFP expression, and Isl1. At terminal differentiation, almost all differentiated neurons express phenotypic markers of motor neurons in GDNF cultures, with lower proportions in control cells. To test if the effects of GDNF were present at early differentiation stages, exogenous recombinant human GDNF was added to control ESC, also resulting in enhanced motor neuron differentiation. This effect was abolished by the co-addition of neutralizing anti-GDNF antibodies, strongly suggesting that differentiating ESC are responsive to GDNF. Using the HB9::GFP reporter, motor neurons were selected for electrophysiological recordings. Motor neurons differentiated from GDNF-ESC, compared to control motor neurons, showed greater electrophysiological maturation, characterized by

  18. Problematic Gaming Behavior Among Finnish Junior High School Students: Relation to Socio-Demographics and Gaming Behavior Characteristics.

    Science.gov (United States)

    Männikkö, Niko; Ruotsalainen, Heidi; Demetrovics, Zsolt; Lopez-Fernandez, Olatz; Myllymäki, Laura; Miettunen, Jouko; Kääriäinen, Maria

    2017-09-14

    Multiplatform digital media use and gaming have been increased in recent years. The aim of this study was to examine associations between sociodemographics and digital gaming behavior characteristics (i.e., gaming time, medium, and genres) with problematic gaming behavior in adolescents. A convenience sample of Finnish junior high school students (n = 560; mean age 14 years, ranging from 12 to 16 years) participated in the cross-sectional survey, of which, 83% (n = 465) reported having played digital games regularly. Sociodemographic data, different forms of digital media use, gaming behavior characteristics and problematic gaming behavior was assessed. Study participants spent on average one hour per day playing digital games; casual games (23.9%), shooting games (19.8%), and sport games (12.9%), were the most popular games among participants. By using regression analysis, a blended family structure and gaming time related positively to problematic gaming behavior. Preferences for game genres such as solo, Massively Multiplayer Online Role-Playing and strategy-management games were also positively associated with problematic use of digital games. These findings provide knowledge that can be utilized in the prevention of the possible negative consequences of digital gaming.

  19. How Massive Multiplayer Online Games Incorporate Principles of Economics

    Science.gov (United States)

    Barnett, Joshua H.; Archambault, Leanna

    2010-01-01

    Games have always been a part of the human experience. Even the earliest of civilizations created games for enjoyment and entertainment. However, the educational value of those games is a relatively recent consideration. Over the previous fifty years, scholars have questioned the potential positive lessons learned from games such as Monopoly[R],…

  20. Video Gaming Promotes Concussion Knowledge Acquisition in Youth Hockey Players

    Science.gov (United States)

    Goodman, David; Bradley, Nori L.; Paras, Bradley, Williamson, Ian J.; Bizzochi, James

    2006-01-01

    While the positive uses for video games in an educational setting have also been established, the educational aim is usually made explicit. The goal of this research was to develop a video game wherein the educational aspect was implicitly embedded in the video game, such that the gameing activity remained interesting and relevant. Following a…

  1. Computer-based learning: games as an instructional strategy.

    Science.gov (United States)

    Blake, J; Goodman, J

    1999-01-01

    Games are a creative teaching strategy that enhances learning and problem solving. Gaming strategies are being used by the authors to make learning interesting, stimulating and fun. This article focuses on the development and implementation of computer games as an instructional strategy. Positive outcomes have resulted from the use of games in the classroom.

  2. Personal, Social, and Game-Related Correlates of Active and Non-Active Gaming Among Dutch Gaming Adolescents: Survey-Based Multivariable, Multilevel Logistic Regression Analyses

    Science.gov (United States)

    de Vet, Emely; Chinapaw, Mai JM; de Boer, Michiel; Seidell, Jacob C; Brug, Johannes

    2014-01-01

    Background Playing video games contributes substantially to sedentary behavior in youth. A new generation of video games—active games—seems to be a promising alternative to sedentary games to promote physical activity and reduce sedentary behavior. At this time, little is known about correlates of active and non-active gaming among adolescents. Objective The objective of this study was to examine potential personal, social, and game-related correlates of both active and non-active gaming in adolescents. Methods A survey assessing game behavior and potential personal, social, and game-related correlates was conducted among adolescents (12-16 years, N=353) recruited via schools. Multivariable, multilevel logistic regression analyses, adjusted for demographics (age, sex and educational level of adolescents), were conducted to examine personal, social, and game-related correlates of active gaming ≥1 hour per week (h/wk) and non-active gaming >7 h/wk. Results Active gaming ≥1 h/wk was significantly associated with a more positive attitude toward active gaming (OR 5.3, CI 2.4-11.8; Pgames (OR 0.30, CI 0.1-0.6; P=.002), a higher score on habit strength regarding gaming (OR 1.9, CI 1.2-3.2; P=.008) and having brothers/sisters (OR 6.7, CI 2.6-17.1; Pgame engagement (OR 0.95, CI 0.91-0.997; P=.04). Non-active gaming >7 h/wk was significantly associated with a more positive attitude toward non-active gaming (OR 2.6, CI 1.1-6.3; P=.035), a stronger habit regarding gaming (OR 3.0, CI 1.7-5.3; P7 h/wk. Active gaming is most strongly (negatively) associated with attitude with respect to non-active games, followed by observed active game behavior of brothers and sisters and attitude with respect to active gaming (positive associations). On the other hand, non-active gaming is most strongly associated with observed non-active game behavior of friends, habit strength regarding gaming and attitude toward non-active gaming (positive associations). Habit strength was a

  3. Learning by gaming - evaluation of an online game for children.

    Science.gov (United States)

    Lazareck, Lisa J; Farrell, David; Kostkova, Patty; Lecky, Donna M; McNulty, Cliodna A M; Weerasinghe, Dasun

    2010-01-01

    Playing computer games is widely popular among children and teenagers as an entertainment activity; meanwhile, playing computer games also provides a learning opportunity. For example, the rules of the game have to be learned by the player in order to improve his/her performance. Based on that principle, the City eHealth Research Centre (CeRC) developed a web game for 13-15 year olds, whereby the player becomes an investigator who attends the scene of an incident that involves microbes. There are four missions in total, each involving a mystery that the player needs to solve and learning objectives that need to be taught - such as antibiotic resistance and the importance of hygiene. This paper presents the results from a game evaluation that took place between July of 2009, in four UK schools (Glasgow, Gloucester, London), with 129 students; whereby 98% of the students commented positively about playing the game. Subsequently, CeRC has improved the game and developed an interactive educational games portal (www.edugames4all.com) for different age groups of web game enthusiasts.

  4. K5/K14-positive cells contribute to salivary gland-like breast tumors with myoepithelial differentiation

    DEFF Research Database (Denmark)

    Boecker, Werner; Stenman, Goeran; Loening, Thomas

    2013-01-01

    different cell lineages and define their cellular hierarchy in tumors with myoepithelial differentiation. isTILT analysis of a series of 28 breast, salivary, and lacrimal gland tumors, including pleomorphic adenomas (n=8), epithelial-myoepithelial tumors (n=9), and adenoid cystic carcinomas (n=11) revealed...... heterologeous cell differentiations such as squamous and mesenchymal progenies. p63 was co-expressed with K5/K14 in basal-like progenitor cells, myoepithelial, and squamous cells but not in glandular cells. Our results show that the corresponding counterpart tumors of breast and salivary/lacrimal glands have....... For that reason, we performed an in situ triple immunofluorescence lineage/differentiation tracing (isTILT) and qRT-PCR study of basal (K5/K14), glandular (K7/K8/18), and epidermal-specific squamous (K10) keratins, p63, and smooth muscle actin (SMA; myoepithelial marker) with the aim to construct and trace...

  5. Epistemic Games

    Science.gov (United States)

    Shaffer, David Williamson

    2005-01-01

    In an article in this issue of "Innovate", Jim Gee asks the question "What would a state of the art instructional video game look like?" Based on the game "Full Spectrum Warrior", he concludes that one model is "to pick [a] domain of authentic professionalism well, intelligently select the skills and knowledge to…

  6. Search Games on Hypergraphs

    NARCIS (Netherlands)

    Pelekis, C.

    2014-01-01

    The main motivation behind this thesis is a certain type of win-lose games that are played on hypergraphs and can be translated into the following puzzle. Suppose there are two persons, say Alice and Bob. There are n biscuits, where n is a positive integer, and Alice chooses s of them uniformly at

  7. The conjugated-strategy game (optimum compatible evolution of coupled systems)

    International Nuclear Information System (INIS)

    Bonnemay, A.

    1967-01-01

    In this report, the two-player game is studied, without certain assumptions usually made: a - the game is not assumed to be a matrix game b - no assumption is made on the cost functions (in particular it is not assumed that they are additive) Results are obtained which are applied to differential games, and lead to an optimal game theorem. These results are then extended to a game with a finite number of players. (author) [fr

  8. Towards a typology of video game trailers: Between the ludic and the cinematic

    OpenAIRE

    Jan Švelch

    2015-01-01

    This paper explores video game trailers, their various forms and the roles they play within video game industry and culture. It offers an overview of the current practice of video game trailer differentiation and proposes a new typology of video game trailers based on their relation to ludic and cinematic aspects of a video game, combining the theory of paratexts, video game performance framework, the interface effect concept, as well as the concept of transmedia storytelling. This typology r...

  9. It's All Part of the Game: Video Game Interaction Design and Business Performance.

    Science.gov (United States)

    Shirinian, Ara

    2001-01-01

    Discusses the importance of positive video game experiences and designs that can create them, including immediacy of feedback, allowing graceful recovery from mistakes, high-quality feedback, and input device mappings. Examines interface complexity. Concludes game designers must treat the interaction between human and video game as a formal…

  10. On the existence of positive periodic solutions for totally nonlinear neutral differential equations of the second-order with functional delay

    Directory of Open Access Journals (Sweden)

    Emmanuel K. Essel

    2014-01-01

    Full Text Available We prove that the totally nonlinear second-order neutral differential equation \\[\\frac{d^2}{dt^2}x(t+p(t\\frac{d}{dt}x(t+q(th(x(t\\] \\[=\\frac{d}{dt}c(t,x(t-\\tau(t+f(t,\\rho(x(t,g(x(t-\\tau(t\\] has positive periodic solutions by employing the Krasnoselskii-Burton hybrid fixed point theorem.

  11. Computer Games for the Math Achievement of Diverse Students

    Science.gov (United States)

    Kim, Sunha; Chang, Mido

    2010-01-01

    Although computer games as a way to improve students' learning have received attention by many educational researchers, no consensus has been reached on the effects of computer games on student achievement. Moreover, there is lack of empirical research on differential effects of computer games on diverse learners. In response, this study…

  12. Radiodine administration under suppression of TSH for identification of false positive receptions in patients with thyroid differentiated carcinoma (TDC): utility of the potassium perchlorate

    International Nuclear Information System (INIS)

    Santangelo, L.A.; Pitoia, F.; Sanz, C.; Niepomniszcze, H.; El Tamer, Elias

    2004-01-01

    The total body scan, after a dose of 131 I correlated with the measurement of stimulated Tg, constitute the principal pillars in follow-up of patients with TDC (thyroid differentiated carcinoma). A bibliographical search revealed more than 70 situations that can cause false total body scans positive. The examination is essential to avoid unnecessary treatment with radioiodine. The object is to evaluate the effectiveness of the radioiodine administration under hormonal therapy thyroid suppressive (THST) to eliminate the possibility of a false total body scan positive in five patients with TDC with stimulated Tg <1ng/ml

  13. The Contribution of Game Genre and other Use Patterns to Problem Video Game Play among Adult Video Gamers.

    Science.gov (United States)

    Elliott, Luther; Ream, Geoffrey; McGinsky, Elizabeth; Dunlap, Eloise

    2012-12-01

    AIMS: To assess the contribution of patterns of video game play, including game genre, involvement, and time spent gaming, to problem use symptomatology. DESIGN: Nationally representative survey. SETTING: Online. PARTICIPANTS: Large sample (n=3,380) of adult video gamers in the US. MEASUREMENTS: Problem video game play (PVGP) scale, video game genre typology, use patterns (gaming days in the past month and hours on days used), enjoyment, consumer involvement, and background variables. FINDINGS: Study confirms game genre's contribution to problem use as well as demographic variation in play patterns that underlie problem video game play vulnerability. CONCLUSIONS: Identification of a small group of game types positively correlated with problem use suggests new directions for research into the specific design elements and reward mechanics of "addictive" video games. Unique vulnerabilities to problem use among certain groups demonstrate the need for ongoing investigation of health disparities related to contextual dimensions of video game play.

  14. The Contribution of Game Genre and other Use Patterns to Problem Video Game Play among Adult Video Gamers

    Science.gov (United States)

    Ream, Geoffrey; McGinsky, Elizabeth; Dunlap, Eloise

    2012-01-01

    Aims To assess the contribution of patterns of video game play, including game genre, involvement, and time spent gaming, to problem use symptomatology. Design Nationally representative survey. Setting Online. Participants Large sample (n=3,380) of adult video gamers in the US. Measurements Problem video game play (PVGP) scale, video game genre typology, use patterns (gaming days in the past month and hours on days used), enjoyment, consumer involvement, and background variables. Findings Study confirms game genre's contribution to problem use as well as demographic variation in play patterns that underlie problem video game play vulnerability. Conclusions Identification of a small group of game types positively correlated with problem use suggests new directions for research into the specific design elements and reward mechanics of “addictive” video games. Unique vulnerabilities to problem use among certain groups demonstrate the need for ongoing investigation of health disparities related to contextual dimensions of video game play. PMID:23284310

  15. Differential relationships in the association of the Big Five personality traits with positive mental health and psychopathology

    NARCIS (Netherlands)

    Lamers, S.M.A.; Westerhof, Gerben Johan; Kovács, Viktòria; Bohlmeijer, Ernst Thomas

    2012-01-01

    According to the two continua model of mental health, psychopathology and positive mental health (emotional, psychological, and social well-being) are related but distinct continua. This study investigates the two continua model by examining whether psychopathology and positive mental health show

  16. Associations between children's video game playing and psychosocial health: Information from both parent and child reports

    NARCIS (Netherlands)

    Lobel, A.M.; Granic, I.; Stone, L.L.; Engels, R.C.M.E.

    2014-01-01

    Video games are a highly heterogeneous form of entertainment. As recent reviews highlight, this heterogeneity makes likely that video games have both positive and negative consequences for child development. This study investigated the associations between gaming frequency and psychosocial health

  17. Positional cloning of the PIS mutation in goats and its impact on understanding mammalian sex-differentiation

    OpenAIRE

    Pailhoux , Eric; Vigier , Bernard; Schibler , Laurent; Edmond P. Cribiu ,; Cotinot , Corinne; Vaiman , Daniel

    2005-01-01

    Abstract In goats, the PIS (polled intersex syndrome) mutation is responsible for both the absence of horns in males and females and sex-reversal affecting exclusively XX individuals. The mode of inheritance is dominant for the polled trait and recessive for sex-reversal. In XX PIS-/- mutants, the expression of testis-specific genes is observed very precociously during gonad development. Nevertheless, a delay of 4–5 days is observed in comparison with normal testis differentiation in XY males...

  18. Creating Evaluation Profiles for Games Designed to be Fun: An Interpretive Framework for Serious Game Mechanics

    DEFF Research Database (Denmark)

    Ulrich, Frank; Helms, Niels Henrik

    2017-01-01

    an interpretive evaluation framework that can identify the educational value in COTS games. Application. The presented framework can create evaluative profiles of the learning, social, game, and immersive mechanics of COTS games as educational tools. Moreover, the framework can position COTS games between four...... intertwined dimensions, namely pedagogical, design, knowledge, and sociotechnical considerations. Demonstration. To validate the practical application of the interpretive framework, we apply it to a real-world example. Our demonstration reveals the usefulness of the framework. Conclusions. The framework...

  19. Cooperative and Non-Cooperative Game Control Strategies of the Ship in Collision Situation

    Directory of Open Access Journals (Sweden)

    Jozef Lisowski

    2018-03-01

    Full Text Available The paper introduces the positional cooperative and non-cooperative game of a greater number of met ships for the description of the process considered as well as for the synthesis of optimal control strategies of the own ship in collision situation. The approximated mathematical model of differential game in the form of triple linear programming problem is used for the synthesis of safe ship trajectory as a multistage process decision. The considerations have been illustrated an example of program computer simulation to determine the safe ship trajectories in situation of passing a many of the ships encountered.

  20. Cognitive behavioral game design: a unified model for designing serious games

    Directory of Open Access Journals (Sweden)

    Katryna eStarks

    2014-02-01

    Full Text Available Video games have a unique ability to engage, challenge, and motivate, which has led teachers, psychology specialists, political activists and health educators to find ways of using them to help people learn, grow and change. Serious games, as they are called, are defined as games that have a primary purpose other than entertainment. However, it is challenging to create games that both educate and entertain. While game designers have embraced some psychological concepts such as flow and mastery, understanding how these concepts work together within established psychological theory would assist them in creating effective serious games. Similarly, game design professionals have understood the propensity of video games to teach while lamenting that educators do not understand how to incorporate educational principles into game play in a way that preserves the entertainment. Albert Bandura’s (1998 social cognitive theory (SCT has been used successfully to create video games that create positive behavior outcomes, and teachers have successfully used Howard Gardner’s (1983 theory of multiple intelligences (MI to create engaging, immersive learning experiences. Cognitive behavioral game design is a new framework that incorporates Social Cognitive Theory (SCT and Multiple Intelligences (MI with game design principles to create a game design blueprint for serious games.

  1. Cognitive behavioral game design: a unified model for designing serious games.

    Science.gov (United States)

    Starks, Katryna

    2014-01-01

    Video games have a unique ability to engage, challenge, and motivate, which has led teachers, psychology specialists, political activists and health educators to find ways of using them to help people learn, grow and change. Serious games, as they are called, are defined as games that have a primary purpose other than entertainment. However, it is challenging to create games that both educate and entertain. While game designers have embraced some psychological concepts such as flow and mastery, understanding how these concepts work together within established psychological theory would assist them in creating effective serious games. Similarly, game design professionals have understood the propensity of video games to teach while lamenting that educators do not understand how to incorporate educational principles into game play in a way that preserves the entertainment. Bandura (2006) social cognitive theory (SCT) has been used successfully to create video games that create positive behavior outcomes, and teachers have successfully used Gardner's (1983) theory of multiple intelligences (MIs) to create engaging, immersive learning experiences. Cognitive behavioral game design is a new framework that incorporates SCT and MI with game design principles to create a game design blueprint for serious games.

  2. [Is video game addiction a reality ?

    Science.gov (United States)

    Thorens, Gabriel; Achab, Sophia; Rothen, Stephane; Khazaal, Yasser; Zullino, Daniele

    2016-09-21

    Video games are widely practiced. Questions about their potential health risks arise, including the risk of addiction. If there is at present no official diagnosis of video games addiction, the DSM-5 proposes temporary criteria based on pathological gambling. Video game addiction affects a minority of at risk individuals. The proposed treatments are essentially psychotherapeutic. Video games practices can be non problematic and they may also have potential beneficial effects on individuals. It is therefore recommended, when assessing video games practices, to take into account the positive and negative impacts of their use.

  3. Are digital games perceived as fun or danger? Supporting and suppressing different game-related concepts.

    Science.gov (United States)

    Kneer, Julia; Glock, Sabine; Beskes, Sara; Bente, Gary

    2012-11-01

    Violent digital game play has repeatedly been discussed to be strongly related to aggression and emotional instability. Thus, digital game players have to defend against these prejudices through emphasizing positive game-related concepts such as achievement, social interaction, and immersion. We experimentally investigated which positive- and negative-concept players and nonplayers activate when being primed with digital games. Participants were either exposed to violent or nonviolent game content and were required to work on a lexical decision task. Results showed that response latencies for the concept aggression and emotional instability were faster than for neutral concepts (not associated with digital games), but slower than for the positive concepts sociality and competition. Both players and nonplayers felt the need to defend against prejudices and emphasized positive concepts. Neither their own gaming experience nor the game content influenced the results. Being a part of the net generation is sufficient to suppress negative game-related concepts and to support positive game-related concepts to protect digital games as common leisure activity among peers.

  4. Individual differences in motives, preferences, and pathology in video games: The gaming attitudes, motives, and experiences scales (GAMES

    Directory of Open Access Journals (Sweden)

    Joseph eHilgard

    2013-09-01

    Full Text Available A new measure of individual habits and preferences in video game use is developed in order to better study the risk factors of pathological game use (i.e., excessively frequent or prolonged use, sometimes called game addiction. This measure was distributed to internet message boards for game enthusiasts and to college undergraduates. An exploratory factor analysis identified 9 factors: Story, Violent Catharsis, Violent Reward, Social Interaction, Escapism, Loss-Sensitivity, Customization, Grinding, and Autonomy. These factors demonstrated excellent fit in a subsequent confirmatory factor analysis, and, importantly, were found to reliably discriminate between inter-individual game preferences (e.g., Super Mario Brothers as compared to Call of Duty. Moreover, three factors were significantly related to pathological game use: the use of games to escape daily life, the use of games as a social outlet, and positive attitudes towards the steady accumulation of in-game rewards. The current research identifies individual preferences and motives relevant to understanding video game players’ evaluations of different games and risk factors for pathological video game use.

  5. Individual differences in motives, preferences, and pathology in video games: the gaming attitudes, motives, and experiences scales (GAMES).

    Science.gov (United States)

    Hilgard, Joseph; Engelhardt, Christopher R; Bartholow, Bruce D

    2013-01-01

    A new measure of individual habits and preferences in video game use is developed in order to better study the risk factors of pathological game use (i.e., excessively frequent or prolonged use, sometimes called "game addiction"). This measure was distributed to internet message boards for game enthusiasts and to college undergraduates. An exploratory factor analysis identified 9 factors: Story, Violent Catharsis, Violent Reward, Social Interaction, Escapism, Loss-Sensitivity, Customization, Grinding, and Autonomy. These factors demonstrated excellent fit in a subsequent confirmatory factor analysis, and, importantly, were found to reliably discriminate between inter-individual game preferences (e.g., Super Mario Brothers as compared to Call of Duty). Moreover, three factors were significantly related to pathological game use: the use of games to escape daily life, the use of games as a social outlet, and positive attitudes toward the steady accumulation of in-game rewards. The current research identifies individual preferences and motives relevant to understanding video game players' evaluations of different games and risk factors for pathological video game use.

  6. Individual differences in motives, preferences, and pathology in video games: the gaming attitudes, motives, and experiences scales (GAMES)

    Science.gov (United States)

    Hilgard, Joseph; Engelhardt, Christopher R.; Bartholow, Bruce D.

    2013-01-01

    A new measure of individual habits and preferences in video game use is developed in order to better study the risk factors of pathological game use (i.e., excessively frequent or prolonged use, sometimes called “game addiction”). This measure was distributed to internet message boards for game enthusiasts and to college undergraduates. An exploratory factor analysis identified 9 factors: Story, Violent Catharsis, Violent Reward, Social Interaction, Escapism, Loss-Sensitivity, Customization, Grinding, and Autonomy. These factors demonstrated excellent fit in a subsequent confirmatory factor analysis, and, importantly, were found to reliably discriminate between inter-individual game preferences (e.g., Super Mario Brothers as compared to Call of Duty). Moreover, three factors were significantly related to pathological game use: the use of games to escape daily life, the use of games as a social outlet, and positive attitudes toward the steady accumulation of in-game rewards. The current research identifies individual preferences and motives relevant to understanding video game players' evaluations of different games and risk factors for pathological video game use. PMID:24058355

  7. An Investigation of Partizan Misere Games

    Science.gov (United States)

    Allen, Meghan Rose

    2010-08-01

    Combinatorial games are played under two different play conventions: normal play, where the last player to move wins, and mis play, where the last player to move loses. Combinatorial games are also classified into impartial positions and partizan positions, where a position is impartial if both players have the same available moves and partizan otherwise. Mis play games lack many of the useful calculational and theoretical properties of normal play games. Until Plambeck's indistinguishability quotient and mis monoid theory were developed in 2004, research on mis play games had stalled. This thesis investigates partizan combinatorial mis play games, by taking Plambeck's indistinguishability and mis monoid theory for impartial positions and extending it to partizan ones, as well as examining the difficulties in constructing a category of mis play games in a similar manner to Joyal's category of normal play games. This thesis succeeds in finding an infinite set of positions which each have finite mis monoid, examining conditions on positions for when * + * is equivalent to 0, finding a set of positions which have Tweedledum-Tweedledee type strategy, and the two most important results of this thesis: giving necessary and sufficient conditions on a set of positions Upsilon such that the mis monoid of Upsilon is the same as the mis monoid of * and giving a construction theorem which builds all positions ξ such that the mis monoid of ξ is the same as the mis monoid of *.

  8. Intelligence is differentially related to neural effort in the task-positive and the task-negative brain network

    NARCIS (Netherlands)

    Basten, U.; Stelzel, C.; Fiebach, C.J.

    2013-01-01

    Previous studies on individual differences in intelligence and brain activation during cognitive processing focused on brain regions where activation increases with task demands (task-positive network, TPN). Our study additionally considers brain regions where activation decreases with task demands

  9. Systematizing game learning analytics for serious games

    NARCIS (Netherlands)

    Alonso-Fernandez, Cristina; Calvo Morata, Antonio; Freire, Manuel; Martinez-Ortiz, Ivan; Fernandez-Manjon, Baltasar

    2017-01-01

    Applying games in education provides multiple benefits clearly visible in entertainment games: their engaging, goal-oriented nature encourages students to improve while they play. Educational games, also known as Serious Games (SGs) are video games designed with a main purpose other than

  10. Amelioration of improper differentiation of somatostatin-positive interneurons by triiodothyronine in a growth-retarded hypothyroid mouse strain.

    Science.gov (United States)

    Uchida, Katsuya; Taguchi, Yusuke; Sato, Chika; Miyazaki, Hidetaka; Kobayashi, Kenichi; Kobayashi, Tetsuya; Itoi, Keiichi

    2014-01-24

    Thyroid hormone (TH) plays an important role in brain development, and TH deficiency during pregnancy or early postnatal periods leads to neurological disorders such as cretinism. Hypothyroidism reduces the number of parvalbumin (PV)-positive interneurons in the neocortex and hippocampus. Here we used a mouse strain (growth-retarded; grt) that shows growth retardation and hypothyroidism to examine whether somatostatin (Sst)-positive interneurons that are generated from the same pool of neural progenitor cells as PV-positive cells are also altered by TH deficiency. The number of PV-positive interneurons was significantly decreased in the neocortex and hippocampus of grt mice as compared with normal control mice. In contrast to the decrease in the number of PV neurons, the number of Sst-positive interneurons in grt mice was increased in the stratum oriens of the hippocampus and the hilus of the dentate gyrus, although their number was unchanged in the neocortex. These changes were reversed by triiodothyronine administration from postnatal day (PD) 0 to 20. TH supplementation that was initiated after PD21 did not, however, affect the number of PV- or Sst-positive cells. These results suggest that during the first three postnatal weeks, TH may be critical for the generation of subpopulations of interneurons. Copyright © 2013 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  11. Differentiation potential of human CD133 positive hematopoietic stem cells into motor neuron- like cells, in vitro.

    Science.gov (United States)

    Moghaddam, Sepideh Alavi; Yousefi, Behnam; Sanooghi, Davood; Faghihi, Faezeh; Hayati Roodbari, Nasim; Bana, Nikoo; Joghataei, Mohammad Taghi; Pooyan, Paria; Arjmand, Babak

    2017-12-01

    Spinal cord injuries and motor neuron-related disorders impact on life of many patients around the world. Since pharmacotherapy and surgical approaches were not efficient to regenerate these types of defects; stem cell therapy as a good strategy to restore the lost cells has become the focus of interest among the scientists. Umbilical cord blood CD133 + hematopoietic stem cells (UCB- CD133 + HSCs) with self- renewal property and neural lineage differentiation capacity are ethically approved cell candidate for use in regenerative medicine. In this regard the aim of this study was to quantitatively evaluate the capability of these cells to differentiate into motor neuron-like cells (MNL), in vitro. CD133 + HSCs were isolated from human UCB using MACS system. After cell characterization using flow cytometry, the cells were treated with a combination of Retinoic acid, Sonic hedgehog, Brain derived neurotrophic factor, and B27 through a 2- step procedure for two weeks. The expression of MN-specific markers was examined using qRT- PCR, flow cytometry and immunocytochemistry. By the end of the two-week differentiation protocol, CD133 + cells acquired unipolar MNL morphology with thin and long neurites. The expression of Isl-1(62.15%), AChE (41.83%), SMI-32 (21.55%) and Nestin (17.46%) was detected using flow cytometry and immunocytochemistry. The analysis of the expression of PAX6, ISL-1, ACHE, CHAT and SMI-32 revealed that MNLs present these neural markers at levels comparable with undifferentiated cells. In Conclusion Human UCB- CD133 + HSCs are remarkably potent cell candidates to transdifferentiate into motor neuron-like cells, in vitro. Copyright © 2017. Published by Elsevier B.V.

  12. Structure coefficients and strategy selection in multiplayer games.

    Science.gov (United States)

    McAvoy, Alex; Hauert, Christoph

    2016-01-01

    Evolutionary processes based on two-player games such as the Prisoner's Dilemma or Snowdrift Game are abundant in evolutionary game theory. These processes, including those based on games with more than two strategies, have been studied extensively under the assumption that selection is weak. However, games involving more than two players have not received the same level of attention. To address this issue, and to relate two-player games to multiplayer games, we introduce a notion of reducibility for multiplayer games that captures what it means to break down a multiplayer game into a sequence of interactions with fewer players. We discuss the role of reducibility in structured populations, and we give examples of games that are irreducible in any population structure. Since the known conditions for strategy selection, otherwise known as [Formula: see text]-rules, have been established only for two-player games with multiple strategies and for multiplayer games with two strategies, we extend these rules to multiplayer games with many strategies to account for irreducible games that cannot be reduced to those simpler types of games. In particular, we show that the number of structure coefficients required for a symmetric game with [Formula: see text]-player interactions and [Formula: see text] strategies grows in [Formula: see text] like [Formula: see text]. Our results also cover a type of ecologically asymmetric game based on payoff values that are derived not only from the strategies of the players, but also from their spatial positions within the population.

  13. [PRODUCT OF THE BMI1--A KEY COMPONENT OF POLYCOMB--POSITIVELY REGULATES ADIPOCYTE DIFFERENTIATION OF MOUSE MESENCHYMAL STEM CELLS].

    Science.gov (United States)

    Petrov, N S; Vereschagina, N A; Sushilova, E N; Kropotov, A V; Miheeva, N F; Popov, B V

    2016-01-01

    Bmil is a key component of Polycomb (PcG), which in mammals controls the basic functions of mammalian somatic stem cells (SSC) such as self-renewal and differentiation. Bmi1 supports SSC via transcriptional suppression of genes associated with cell cycle and differentiation. The most studied target genes of Bmi1 are the genes of Ink4 locus, CdkI p16(Ink4a) and p1(Arf), suppression of which due to activating mutations of the BMI1 results in formation of cancer stem cells (CSC) and carcinomas in various tissues. In contrast, inactivation of BMI1 results in cell cycle arrest and cell senescence. Although clinical phenomena of hypo- and hyperactivation of BMI1 are well known, its targets and mechanisms of regulation of tissue specific SSC are still obscure. The goal of this study was to evaluate the regulatory role of BMI1 in adipocyte differentiation (AD) of mouse mesenchymal stem cells (MSC). Induction of AD in mouse MSC of the C3H10T1/2 cell line was associated with an increase in the expression levels of BMI1, the genes of pRb family (RB, p130) and demethylase UTX, but not methyltransferase EZH2, whose products regulate the methylation levels of H3K27. It was observed earlier that H3K27me3 may play the role of the epigenetic switch by promoting AD of human MSC via activating expression of the PPARγ2, the master gene of AD (Hemming et al., 2014). Here we show that inactivation of BMI1 using specific siRNA slows and decreases the levels of AD, but does not abolish it. This is associated with a complete inhibition of the expression of adipogenic marker genes--PPARγ2, ADIPOQ and a decrease in the expression of RB, p130, but not UTX. The results obtained give evidence that the epigenetic mechanism regulating AD differentiation in mouse and human MSC is different.

  14. Natural games

    Science.gov (United States)

    Anttila, Jani; Annila, Arto

    2011-10-01

    A course of a game is formulated as a physical process that will consume free energy in the least time. Accordingly, the rate of entropy increase is the payoff function that will subsume all forms of free energy that motivate diverse decisions. Also other concepts of game theory are related to their profound physical counterparts. When the physical portrayal of behavior is mathematically analyzed, the course of a game is found to be inherently unpredictable because each move affects motives in the future. Despite the non-holonomic character of the natural process, the objective of consuming free energy in the least time will direct an extensive-form game toward a Lyapunov-stable point that satisfies the minimax theorem.

  15. Golden Games

    Institute of Scientific and Technical Information of China (English)

    LI XIAO

    2010-01-01

    @@ China is not expected to sweep the Vancouver 2010 Olympic Winter Games the way it dominated the 2008 Beijing Summer Olympics.However,it has made Chinese Olympic history after winning three gold medals when the Games passed the halfway point of scheduled competition on February 20.On that day,18-year-old Zhou Yang overcame three South Korean rivals to win the women's short-track speed skating 1,500-meter final.

  16. Anthropometric and physical characteristics allow differentiation of young female volleyball players according to playing position and level of expertise

    Science.gov (United States)

    Milić, M; Grgantov, Z; Chamari, K; Bianco, A; Padulo, J

    2016-01-01

    The aim of our study was to determine the differences in some anthropometric and physical performance variables of young Croatian female volleyball players (aged 13 to 15) in relation to playing position (i.e., independent variable) and performance level within each position (i.e., independent variable). Players were categorized according to playing position (i.e., role) as middle blockers (n=28), opposite hitters (n=41), passer-hitters (n=54), setters (n=30), and liberos (n=28). Within each position, players were divided into a more successful group and a less successful group according to team ranking in the latest regional championship and player quality within the team. Height and body mass, somatotype by the Heath-Carter method, and four tests of lower body power, speed, agility and upper body power (i.e., dependent variables) were assessed. Players in different positions differed significantly in height and all three somatotype components, but no significant differences were found in body mass, body mass index or measured physical performance variables. Players of different performance level differed significantly in both anthropometric and physical performance variables. Generally, middle blockers were taller, more ectomorphic, less mesomorphic and endomorphic, whereas liberos were shorter, less ectomorphic, more mesomorphic and endomorphic than players in other positions. More successful players in all positions had a lower body mass index, were less mesomorphic and endomorphic, and more ectomorphic than less successful players. Furthermore, more successful players showed better lower body power, speed, agility and upper body power. The results of this study can potentially provide coaches with useful indications about the use of somatotype selection and physical performance assessment for talent identification and development. PMID:28416892

  17. Playing Games with Timed Games

    DEFF Research Database (Denmark)

    David, Alexandre; Larsen, Kim Guldstrand; Chatain, Thomas

    2009-01-01

    In this paper we focus on property-preserving preorders between timed game automata and their application to control of partially observable systems. Following the example of timed simulation between timed automata, we define timed alternating simulation as a preorder between timed game automata......, which preserves controllability. We define a method to reduce the timed alternating simulation problem to a safety game. We show how timed alternating simulation can be used to control efficiently a partially observable system. This method is illustrated by a generic case study....

  18. Players' expertise and competition with others shape the satisfaction of competence needs, gaming gratifications, and contingent self-esteem in a gaming context.

    Science.gov (United States)

    Kazakova, Snezhanka; Cauberghe, Veroline; Pandelaere, Mario; De Pelsmacker, Patrick

    2014-01-01

    The current study explores how competition and gaming expertise affect the satisfaction of competence needs and gaming gratifications. We demonstrate that competition moderates the effect of gaming expertise on the satisfaction of competence needs, which in turn affects game enjoyment and replay intention. Gaming expertise predicted players' need satisfaction, game enjoyment, and replay intention significantly better in a competitive compared to a noncompetitive context. The effect of gaming expertise on game enjoyment and replay intention was, furthermore, mediated by the satisfaction of competence needs. Finally, gaming expertise positively affected the importance of competition for players' self-esteem only in the competitive gaming context. The present findings demonstrate the importance of competition and gaming expertise for the satisfaction of competence needs, gaming gratifications, and the pursuit of self-esteem during gameplay, attesting to the applicability of self-determination theory to gaming contexts.

  19. "Grand Theft South Africa": Games, Literacy and Inequality in Consumer Childhoods

    Science.gov (United States)

    Walton, Marion; Pallitt, Nicola

    2012-01-01

    Discussions of "game literacy" focus on the informal learning and literacies associated with games but seldom address the diversity in young people's gaming practices, and the highly differentiated technologies of digital gaming in use. We use available survey data to show how, in South Africa, income inequalities influence consumption…

  20. Natural games

    International Nuclear Information System (INIS)

    Anttila, Jani; Annila, Arto

    2011-01-01

    A course of a game is formulated as a physical process that will consume free energy in the least time. Accordingly, the rate of entropy increase is the payoff function that will subsume all forms of free energy that motivate diverse decisions. Also other concepts of game theory are related to their profound physical counterparts. When the physical portrayal of behavior is mathematically analyzed, the course of a game is found to be inherently unpredictable because each move affects motives in the future. Despite the non-holonomic character of the natural process, the objective of consuming free energy in the least time will direct an extensive-form game toward a Lyapunov-stable point that satisfies the minimax theorem. -- Highlights: → Behavior in the context of game theory is described as a natural process. → The rate of entropy increase, derived from statistical physics of open systems, is identified as the payoff function. → Entropy as the payoff function also clarifies motives of collaboration and subjective nature of decision making. → Evolutionary equation of motion that accounts for the course of a game is inherently unpredictable.

  1. Game development tool essentials

    CERN Document Server

    Berinstein, Paula; Ardolino, Alessandro; Franco, Simon; Herubel, Adrien; McCutchan, John; Nedelcu, Nicusor; Nitschke, Benjamin; Olmstead, Don; Robinet, Fabrice; Ronchi, Christian; Turkowski, Rita; Walter, Robert; Samour, Gustavo

    2014-01-01

    Offers game developers new techniques for streamlining the critical game tools pipeline. Inspires game developers to share their secrets and improve the productivity of the entire industry. Helps game industry practitioners compete in a hyper-competitive environment.

  2. Step out - Step in Sequencing Games

    NARCIS (Netherlands)

    Musegaas, M.; Borm, P.E.M.; Quant, M.

    2014-01-01

    In this paper a new class of relaxed sequencing games is introduced: the class of Step out - Step in sequencing games. In this relaxation any player within a coalition is allowed to step out from his position in the processing order and to step in at any position later in the processing order.

  3. Step out-step in sequencing games

    NARCIS (Netherlands)

    Musegaas, Marieke; Borm, Peter; Quant, Marieke

    2015-01-01

    In this paper a new class of relaxed sequencing games is introduced: the class of Step out–Step in sequencing games. In this relaxation any player within a coalition is allowed to step out from his position in the processing order and to step in at any position later in the processing order. First,

  4. Alexithymia Components Are Differentially Related to Explicit Negative Affect But Not Associated with Explicit Positive Affect or Implicit Affectivity.

    Science.gov (United States)

    Suslow, Thomas; Donges, Uta-Susan

    2017-01-01

    Alexithymia represents a multifaceted personality construct defined by difficulties in recognizing and verbalizing emotions and externally oriented thinking. According to clinical observations, experience of negative affects is exacerbated and experience of positive affects is decreased in alexithymia. Findings from research based on self-report indicate that all alexithymia facets are negatively associated with the experience of positive affects, whereas difficulties identifying and describing feelings are related to heightened negative affect. Implicit affectivity, which can be measured using indirect assessment methods, relates to processes of the impulsive system. The aim of the present study was to examine, for the first time, the relations between alexithymia components and implicit and explicit positive and negative affectivity in healthy adults. The 20-item Toronto Alexithymia Scale, the Implicit Positive and Negative Affect Test and the Positive and Negative Affect Schedule (PANAS) were administered to two hundred and forty-one healthy individuals along with measures of depression and trait anxiety. Difficulties identifying feelings were correlated with explicit negative trait affect, depressive mood and trait anxiety. Difficulties describing feelings showed smaller but also significant correlations with depressive mood and trait anxiety but were not correlated with explicit state or trait affect as assessed by the PANAS. Externally oriented thinking was not significantly correlated with any of the implicit and explicit affect measures. According to our findings, an externally oriented, concrete way of thinking appears to be generally unrelated to dispositions to develop positive or negative affects. Difficulties identifying feelings seem to be associated with increased conscious negative affects but not with a heightened disposition to develop negative affects at an automatic response level.

  5. Alexithymia Components Are Differentially Related to Explicit Negative Affect But Not Associated with Explicit Positive Affect or Implicit Affectivity

    Directory of Open Access Journals (Sweden)

    Thomas Suslow

    2017-10-01

    Full Text Available Alexithymia represents a multifaceted personality construct defined by difficulties in recognizing and verbalizing emotions and externally oriented thinking. According to clinical observations, experience of negative affects is exacerbated and experience of positive affects is decreased in alexithymia. Findings from research based on self-report indicate that all alexithymia facets are negatively associated with the experience of positive affects, whereas difficulties identifying and describing feelings are related to heightened negative affect. Implicit affectivity, which can be measured using indirect assessment methods, relates to processes of the impulsive system. The aim of the present study was to examine, for the first time, the relations between alexithymia components and implicit and explicit positive and negative affectivity in healthy adults. The 20-item Toronto Alexithymia Scale, the Implicit Positive and Negative Affect Test and the Positive and Negative Affect Schedule (PANAS were administered to two hundred and forty-one healthy individuals along with measures of depression and trait anxiety. Difficulties identifying feelings were correlated with explicit negative trait affect, depressive mood and trait anxiety. Difficulties describing feelings showed smaller but also significant correlations with depressive mood and trait anxiety but were not correlated with explicit state or trait affect as assessed by the PANAS. Externally oriented thinking was not significantly correlated with any of the implicit and explicit affect measures. According to our findings, an externally oriented, concrete way of thinking appears to be generally unrelated to dispositions to develop positive or negative affects. Difficulties identifying feelings seem to be associated with increased conscious negative affects but not with a heightened disposition to develop negative affects at an automatic response level.

  6. Towards a typology of video game trailers: Between the ludic and the cinematic

    Directory of Open Access Journals (Sweden)

    Jan Švelch

    2015-09-01

    Full Text Available This paper explores video game trailers, their various forms and the roles they play within video game industry and culture. It offers an overview of the current practice of video game trailer differentiation and proposes a new typology of video game trailers based on their relation to ludic and cinematic aspects of a video game, combining the theory of paratexts, video game performance framework, the interface effect concept, as well as the concept of transmedia storytelling. This typology reflects the historical evolution of a video game trailer and also takes into account current trends in the audiovisual paratexts of video games.

  7. Electronic gaming and psychosocial adjustment.

    Science.gov (United States)

    Przybylski, Andrew K

    2014-09-01

    The rise of electronic games has driven both concerns and hopes regarding their potential to influence young people. Existing research identifies a series of isolated positive and negative effects, yet no research to date has examined the balance of these potential effects in a representative sample of children and adolescents. The objective of this study was to explore how time spent playing electronic games accounts for significant variation in positive and negative psychosocial adjustment using a representative cohort of children aged 10 to 15 years. A large sample of children and adolescents aged 10 to 15 years completed assessments of psychosocial adjustment and reported typical daily hours spent playing electronic games. Relations between different levels of engagement and indicators of positive and negative psychosocial adjustment were examined, controlling for participant age and gender and weighted for population representativeness. Low levels (3 hours daily) of game engagement was linked to key indicators of psychosocial adjustment. Low engagement was associated with higher life satisfaction and prosocial behavior and lower externalizing and internalizing problems, whereas the opposite was found for high levels of play. No effects were observed for moderate play levels when compared with non-players. The links between different levels of electronic game engagement and psychosocial adjustment were small (Games consistently but not robustly associated with children's adjustment in both positive and negative ways, findings that inform policy-making as well as future avenues for research in the area. Copyright © 2014 by the American Academy of Pediatrics.

  8. Game mechanics engine

    OpenAIRE

    Magnusson, Lars V

    2011-01-01

    Game logic and game rules exists in all computer games, but they are created di erently for all game engines. This game engine dependency exists because of how the internal object model is implemented in the engine, as a place where game logic data is intermingled with the data needed by the low- level subsystems. This thesis propose a game object model design, based on existing theory, that removes this dependency and establish a general game logic framework. The thesis the...

  9. Whole-genome sequencing of two North American Drosophila melanogaster populations reveals genetic differentiation and positive selection.

    Science.gov (United States)

    Campo, D; Lehmann, K; Fjeldsted, C; Souaiaia, T; Kao, J; Nuzhdin, S V

    2013-10-01

    The prevailing demographic model for Drosophila melanogaster suggests that the colonization of North America occurred very recently from a subset of European flies that rapidly expanded across the continent. This model implies a sudden population growth and range expansion consistent with very low or no population subdivision. As flies adapt to new environments, local adaptation events may be expected. To describe demographic and selective events during North American colonization, we have generated a data set of 35 individual whole-genome sequences from inbred lines of D. melanogaster from a west coast US population (Winters, California, USA) and compared them with a public genome data set from Raleigh (Raleigh, North Carolina, USA). We analysed nuclear and mitochondrial genomes and described levels of variation and divergence within and between these two North American D. melanogaster populations. Both populations exhibit negative values of Tajima's D across the genome, a common signature of demographic expansion. We also detected a low but significant level of genome-wide differentiation between the two populations, as well as multiple allele surfing events, which can be the result of gene drift in local subpopulations on the edge of an expansion wave. In contrast to this genome-wide pattern, we uncovered a 50-kilobase segment in chromosome arm 3L that showed all the hallmarks of a soft selective sweep in both populations. A comparison of allele frequencies within this divergent region among six populations from three continents allowed us to cluster these populations in two differentiated groups, providing evidence for the action of natural selection on a global scale. © 2013 John Wiley & Sons Ltd.

  10. Winning Cores in Parity Games

    DEFF Research Database (Denmark)

    Vester, Steen

    2016-01-01

    We introduce the novel notion of winning cores in parity games and develop a deterministic polynomial-time under-approximation algorithm for solving parity games based on winning core approximation. Underlying this algorithm are a number properties about winning cores which are interesting...... in their own right. In particular, we show that the winning core and the winning region for a player in a parity game are equivalently empty. Moreover, the winning core contains all fatal attractors but is not necessarily a dominion itself. Experimental results are very positive both with respect to quality...

  11. Drinking Game Studies

    DEFF Research Database (Denmark)

    Debus, Michael S.

    2016-01-01

    The paper examines research on drinking game participation from a game studies ontological perspective, covering definition, classification and problems with the, in the studies implied, underlying ontology of drinking games.......The paper examines research on drinking game participation from a game studies ontological perspective, covering definition, classification and problems with the, in the studies implied, underlying ontology of drinking games....

  12. Persuasive Game Design : A model and its definitions

    NARCIS (Netherlands)

    Visch, V.T.; Vegt, N.J.H.; Anderiesen, H.; Van der Kooij, K.

    2013-01-01

    The following position paper proposes a general theoretical model for persuasive game design. This model combines existing theories on persuasive technology, serious gaming, and gamification. The model is based on user experience, gamification design, and transfer effects.

  13. Superman vs. BAD man? The effects of empathy and game character in violent video games.

    Science.gov (United States)

    Happ, Christian; Melzer, André; Steffgen, Georges

    2013-10-01

    Recent findings indicate that events in video games, as well as players' perceptions of game characters, moderate well-established video game effects. This includes the level of identification with game characters, and players' interpretation of whether or not the actions of the characters are conceived as moral. In the present study, it was tested whether manipulating empathy for well-known game characters influences video game effects in a violent beat-'em-up game. As was expected, playing the comic hero Superman led to more prosocial behavior (i.e., returning a lost letter) than playing the evil villain Joker. A similar positive effect was observed for inducing game characters as warm and empathic before playing. Compared to a neutral text, participants in the empathy text condition judged the violence in the game as less justified, irrespective of game character. When looking at hostile perception, an interaction was found between empathy and game character. For Superman, empathy led participants to interpret neutral faces as less aggressive. When playing the evil Joker, however, empathy even increased hostile perception. This is in line with previous findings that empathy may not be positive per se. In fact, it may backfire depending on the interaction of game characters and the empathy players feel for them.

  14. Gamers on Games and Gaming : Implications for Educational Game Design

    NARCIS (Netherlands)

    Van Staalduinen, J.P.

    2012-01-01

    In the past two decades, there has been a steadily increasing interest in the use of games for educational purposes. This has led to an increased design, use and study of educational games; games where the players learn through playing. However, experiments with the educational use of games have not

  15. A Probabilistic-Numerical Approximation for an Obstacle Problem Arising in Game Theory

    International Nuclear Information System (INIS)

    Grün, Christine

    2012-01-01

    We investigate a two-player zero-sum stochastic differential game in which one of the players has more information on the game than his opponent. We show how to construct numerical schemes for the value function of this game, which is given by the solution of a quasilinear partial differential equation with obstacle.

  16. A Probabilistic-Numerical Approximation for an Obstacle Problem Arising in Game Theory

    Energy Technology Data Exchange (ETDEWEB)

    Gruen, Christine, E-mail: christine.gruen@univ-brest.fr [Laboratoire de Mathematiques de Brest UMR 6205 (France)

    2012-12-15

    We investigate a two-player zero-sum stochastic differential game in which one of the players has more information on the game than his opponent. We show how to construct numerical schemes for the value function of this game, which is given by the solution of a quasilinear partial differential equation with obstacle.

  17. Positional mapping and candidate gene analysis of the mouse Ccs3 locus that regulates differential susceptibility to carcinogen-induced colorectal cancer.

    Directory of Open Access Journals (Sweden)

    Charles Meunier

    Full Text Available The Ccs3 locus on mouse chromosome 3 regulates differential susceptibility of A/J (A, susceptible and C57BL/6J (B6, resistant mouse strains to chemically-induced colorectal cancer (CRC. Here, we report the high-resolution positional mapping of the gene underlying the Ccs3 effect. Using phenotype/genotype correlation in a series of 33 AcB/BcA recombinant congenic mouse strains, as well as in groups of backcross populations bearing unique recombinant chromosomes for the interval, and in subcongenic strains, we have delineated the maximum size of the Ccs3 physical interval to a ∼2.15 Mb segment. This interval contains 12 annotated transcripts. Sequencing of positional candidates in A and B6 identified many either low-priority coding changes or non-protein coding variants. We found a unique copy number variant (CNV in intron 15 of the Nfkb1 gene. The CNV consists of two copies of a 54 bp sequence immediately adjacent to the exon 15 splice site, while only one copy is found in CRC-susceptible A. The Nfkb1 protein (p105/p50 expression is much reduced in A tumors compared to normal A colonic epithelium as analyzed by immunohistochemistry. Studies in primary macrophages from A and B6 mice demonstrate a marked differential activation of the NfκB pathway by lipopolysaccharide (kinetics of stimulation and maximum levels of phosphorylated IκBα, with a more robust activation being associated with resistance to CRC. NfκB has been previously implicated in regulating homeostasis and inflammatory response in the intestinal mucosa. The interval contains another positional candidate Slc39a8 that is differentially expressed in A vs B6 colons, and that has recently been associated in CRC tumor aggressiveness in humans.

  18. Analyzing online game players: from materialism and motivation to attitude.

    Science.gov (United States)

    Chang, Ju-Hui; Zhang, Hongxia

    2008-12-01

    The online game market has been growing rapidly and has received an increasing amount of attention in recent years. The results of a survey conducted in China to explore online game players' attitude formation reveal that (a) the online game player's level of materialism positively influences the motivation for playing, (b) motivation positively influences attitude toward online games, and (c) motivation fully mediates the effects of materialism on attitude.

  19. Positive solutions of a three-point boundary-value problem for differential equations with damping and actively bounded delayed forcing term

    Directory of Open Access Journals (Sweden)

    George L. Karakostas

    2006-08-01

    Full Text Available We provide sufficient conditions for the existence of positive solutions of a three-point boundary value problem concerning a second order delay differential equation with damping and forcing term whose the delayed part is an actively bounded function, a meaning introduced in [19]. By writing the damping term as a difference of two factors one can extract more information on the solutions. (For instance, in an application, given in the last section, we can give the exact value of the norm of the solution.

  20. Differential Risk for Homelessness Among US Male and Female Veterans With a Positive Screen for Military Sexual Trauma.

    Science.gov (United States)

    Brignone, Emily; Gundlapalli, Adi V; Blais, Rebecca K; Carter, Marjorie E; Suo, Ying; Samore, Matthew H; Kimerling, Rachel; Fargo, Jamison D

    2016-06-01

    Military sexual trauma (MST) is associated with adverse physical and mental health outcomes following military separation. Recent research suggests that MST may be a determinant in several factors associated with postdeployment homelessness. To evaluate MST as an independent risk factor for homelessness and to determine whether risk varies by sex. A retrospective cohort study of US veterans who used Veterans Health Administration (VHA) services between fiscal years 2004 and 2013 was conducted using administrative data from the Department of Defense and VHA. Included in the study were 601 892 US veterans deployed in Iraq or Afghanistan who separated from the military between fiscal years 2001 and 2011 and subsequently used VHA services. Positive response to screen for MST administered in VHA facilities. Administrative evidence of homelessness within 30 days, 1 year, and 5 years following the first VHA encounter after last deployment. The mean (SD) age of the 601 892 participants was 38.9 (9.4) years, 527 874 (87.7%) were male, 310 854 (51.6%) were white, and 382 361 (63.5%) were enlisted in the Army. Among veterans with a positive screen for MST, rates of homelessness were 1.6% within 30 days, 4.4% within 1 year, and 9.6% within 5 years, more than double the rates of veterans with a negative MST screen (0.7%, 1.8%, and 4.3%, respectively). A positive screen for MST was significantly and independently associated with postdeployment homelessness. In regression models adjusted for demographic and military service characteristics, odds of experiencing homelessness were higher among those who screened positive for MST compared with those who screened negative (30-day: adjusted odds ratio [AOR], 1.89; 95% CI, 1.58-2.24; 1-year: AOR, 2.27; 95% CI, 2.04-2.53; and 5-year: AOR, 2.63; 95% CI, 2.36-2.93). Military sexual trauma screen status remained independently associated with homelessness after adjusting for co-occurring mental health and substance abuse diagnoses

  1. Positive muscle protein net balance and differential regulation of atrogene expression after resistance exercise and milk protein supplementation

    DEFF Research Database (Denmark)

    Reitelseder, Søren; Agergaard, Jakob; Doessing, Simon

    2014-01-01

    Purpose Resistance exercise and amino acid availability are positive regulators of muscle protein net balance (NB). However, anabolic responses to resistance exercise and protein supplementation deserve further elucidation. The purpose was to compare intakes of whey, caseinate (both: 0.30 g/kg lean...... body mass), or a non-caloric control after heavy resistance exercise on protein turnover and mRNA expressions of forkhead homeobox type O (FOXO) isoforms, muscle RING finger 1 (MuRF1), and Atrogin1 in young healthy males. Methods Protein turnover was determined by stable isotope-labeled leucine...

  2. General game playing

    CERN Document Server

    Genesereth, Michael

    2014-01-01

    General game players are computer systems able to play strategy games based solely on formal game descriptions supplied at ""runtime"" (n other words, they don't know the rules until the game starts). Unlike specialized game players, such as Deep Blue, general game players cannot rely on algorithms designed in advance for specific games; they must discover such algorithms themselves. General game playing expertise depends on intelligence on the part of the game player and not just intelligence of the programmer of the game player.GGP is an interesting application in its own right. It is intell

  3. Serious Games

    DEFF Research Database (Denmark)

    Christensen, Jens

    Serious Games er et nyt it-forretningsområde, der siden årtusindskiftet er vokset frem, først i USA og dernæst i Vesteuropa og and i-lande. Til forskel fra computerspil er serious games ikke underholdning, men tænkt som et værktøj til støtte for statens og erhvervslivets forskellige funktioner. Det...... amerikanske militær har været fødselshjælper for den nye teknologi. Herfra har serious games bredt sig til andre sektorer og og i-lande, inkl. Danmark. Bogen skildrer, hvordan det nye forretningsområde er i færd med at blive udkrystalliseret af en række beslægtede industrigrene, og hvordan udviklingen er...

  4. Serious Games

    DEFF Research Database (Denmark)

    Salovaara-Moring, Inka

    There has recently been considerable attention paid to the gamification of digital journalism. Where the current technological and social affordances of web 2.0 storytelling have proved less attractive to younger users, the persuasive features of game logics have added new dimensions to interactive......, participatory journalism. This notion refers to realitybased news games that can act both as an independent medium for news content and as a supplement to traditional forms of coverage. Simultaneously, persuasive logics of gamification offer new ways to engage actuality through media space’s augmented reality....... This paper1 explores the new spatio-epistemological realities of two journalistic games, asking how the spatial, operational, and procedural realities of storytelling change through ‘gamification’. It reflects on the spatial dimension of digital journalism in order to challenge the traditional, generic...

  5. Sport Education as a Curriculum Approach to Student Learning of Invasion Games: Effects on Game Performance and Game Involvement

    Science.gov (United States)

    Farias, Cláudio; Valério, Carla; Mesquita, Isabel

    2018-01-01

    the game forms played by students either inhibited or enabled their game-play development. Key points The effect of time fostered by the extended participation of students in consecutive seasons of the model was paramount to promote effective gains in Game Performance and Game Involvement. Specific modifications imposed on the game, such as asymmetric attack-defense game configurations had a positive effect on the development of the learning outcomes. The persistent membership that was extended across sequential units of invasion games helped players build more sophisticated game-play routines and problem-solving. PMID:29535578

  6. CHRISTMAS 2015 : THE PUBLICATION GAME Use of positive and negative words in scientific PubMed abstracts between 1974 and 2014: retrospective analysis

    NARCIS (Netherlands)

    Vinkers, Christiaan H.; Tijdink, Joeri K.; Otte, Wim

    2015-01-01

    Objective To investigate whether language used in science abstracts can skew towards the use of strikingly positive and negative words over time. Design Retrospective analysis of all scientific abstracts in PubMed between 1974 and 2014. Methods The yearly frequencies of positive, negative, and

  7. Differential Effects of Intraoperative Positive End-expiratory Pressure (PEEP) on Respiratory Outcome in Major Abdominal Surgery Versus Craniotomy

    DEFF Research Database (Denmark)

    de Jong, Myrthe A C; Ladha, Karim S; Melo, Marcos F Vidal

    2015-01-01

    OBJECTIVES: In this study, we examined whether (1) positive end-expiratory pressure (PEEP) has a protective effect on the risk of major postoperative respiratory complications in a cohort of patients undergoing major abdominal surgeries and craniotomies, and (2) the effect of PEEP is differed......: Within the entire study population (major abdominal surgeries and craniotomies), we found an association between application of PEEP ≥5 cmH2O and a decreased risk of postoperative respiratory complications compared with PEEP 5 cmH2O was associated with a significant lower...... undergoing major abdominal surgery. Our data suggest that default mechanical ventilator settings should include PEEP of 5-10 cmH2O during major abdominal surgery....

  8. The Evaluation of CEIT Teacher Candidates in Terms of Computer Games, Educational Use of Computer Games and Game Design Qualifications

    Directory of Open Access Journals (Sweden)

    Hakkı BAĞCI

    2014-04-01

    Full Text Available Computer games have an important usage potential in the education of today’s digital student profile. Also computer teachers known as technology leaders in schools are the main stakeholders of this potential. In this study, opinions of the computer teachers about computer games are examined from different perspectives. 119 computer teacher candidates participated in this study, and the data were collected by a questionnaire. As a result of this study, computer teacher candidates have a positive thinking about the usage of computer games in education and they see themselves qualified for the analysis and design of educational games. But they partially have negative attitudes about some risks like addiction and lose of time. Also the candidates who attended the educational game courses and play games from their mobile phones have more positive opinions, and they see themselves more qualified than others. Males have more positive opinions about computer games than females, but in terms of educational games and the analysis and design of the computer games, there is no significant difference between males and females.

  9. Game theory and mercosul

    Directory of Open Access Journals (Sweden)

    Romeu Costa Ribeiro Bastos

    2011-06-01

    Full Text Available The processes of regional integration has aroused great interest in the field of International Relations since the 1950s, however, there has been renovated enthusiasm especially in the 1980s, in view of the successful experience of European Union and the creation of Mercosur. This article aims at analyzing the positions of Brazil and Argentina within Mercosur, using the instruments supplied by the Game Theory.

  10. False positive or negative results of shear-wave elastography in differentiating benign from malignant breast masses: analysis of clinical and ultrasonographic characteristics.

    Science.gov (United States)

    Kim, Mi Young; Choi, Nami; Yang, Jung-Hyun; Yoo, Young Bum; Park, Kyoung Sik

    2015-10-01

    Shear-wave elastography (SWE) has the potential to improve diagnostic performance of conventional ultrasound (US) in differentiating benign from malignant breast masses. To investigate false positive or negative results of SWE in differentiating benign from malignant breast masses and to analyze clinical and imaging characteristics of the masses with false SWE findings. From May to October 2013, 166 breast lesions of 164 consecutive women (mean age, 45.3 ± 10.1 years) who had been scheduled for biopsy were included. Conventional US and SWE were performed in all women before biopsy. Clinical, ultrasonographic morphologic features and SWE parameters (pattern classification and standard deviation [SD]) were recorded and compared with the histopathology results. Patient and lesion factors in the "true" and "false" groups were compared. Of the 166 masses, 118 (71.1%) were benign and 48 (28.9%) were malignant. False SWE features were more frequently observed in benign masses. False positive rates of benign masses and false negative rates of malignancy were 53% and 8.2%, respectively, using SWE pattern analysis and were 22.4% and 10.3%, respectively, using SD values. A lesion boundary of the masses on US (P = 0.039) and younger patient age (P = 0.047) were significantly associated with false SWE findings. These clinical and ultrasonographic features need to be carefully evaluated in performance and interpretation of SWE examinations. © The Foundation Acta Radiologica 2014.

  11. Bringing your a-game: Educational gaming for student success.

    Science.gov (United States)

    Strickland, Haley P; Kaylor, Sara K

    2016-05-01

    The purpose of this article is to describe the theoretical basis for the integration of gaming in nursing education and discuss aspects related to the implementation of "The Race for Nursing Student Success" game. This game was designed for 112 junior-level baccalaureate nursing students enrolled in a fundamentals nursing course. Students were divided into groups of 5-8 and rotated through ten specific learning activities that took place in various locations throughout the nursing building. Student and faculty feedback indicated positive responses to this instructional strategy and also promoted a learner-centered teaching environment. This learning activity supports the use of educational gaming as a means to develop learner-centered environments that provide experiential experiences, enhance learning, and stimulate interest, and motivation for students to learn. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. The Number of Pathologically Positive Lymph Nodes and Pathological Tumor Depth Predicts Prognosis in Patients With Poorly Differentiated Squamous Cell Carcinoma of the Oral Cavity

    International Nuclear Information System (INIS)

    Kang, Chung-Jan; Lin, Chien-Yu; Wang, Hung-Ming; Fan, Kang-Hsing; Ng, Shu-Hang; Lee, Li-Yu; Chen, I-How; Huang, Shiang-Fu

    2011-01-01

    Purpose: The objective of this retrospective study was twofold: (1) to investigate prognostic factors for clinical outcomes in patients with poorly differentiated oral cavity squamous cell carcinoma and (2) to identify specific prognostic subgroups that may help to guide treatment decisions. Methods and Materials: We examined 102 patients with poorly differentiated oral cavity squamous cell carcinoma. All patients were followed for at least 24 months after surgery or until death. The 5-year rates of local control, neck control, distant metastasis, disease-free, disease-specific, and overall survival served as main outcome measures. Results: The 5-year rates were as follows: local control (79%), neck control (64%), distant metastases (27%), disease-free survival (48%), disease-specific survival (52%), and overall survival (42%). Multivariable analysis showed that the number of pathologically positive nodes (≥4 vs. ≤3) was a significant predictor of neck control, distant metastasis, and disease-free, disease-specific, and overall survival rates. In addition, the presence of tumor depth of ≥11 mm (vs. <11 mm) was a significant predictor of distant metastasis, disease-specific survival, and overall survival rates. The combination of the two predictors (26.5%, 27/102) was independently associated with poorer neck control (p = 0.0319), distant metastasis (p < 0.0001), and disease-free (p < 0.0001), disease-specific (p < 0.0001), and overall survival (p < 0.0001) rates. Conclusions: In patients with poorly differentiated oral cavity squamous cell carcinoma, the presence of at least 4 pathologically positive lymph nodes and of a pathological tumor depth ≥11 mm identifies a subset of subjects with poor clinical outcomes. Patients carrying both risk factors are suitable candidates for the development of novel therapeutic approaches.

  13. Serious Games: Video Games for Good?

    Science.gov (United States)

    Sanford, Kathy; Starr, Lisa J.; Merkel, Liz; Bonsor Kurki, Sarah

    2015-01-01

    As video games become a ubiquitous part of today's culture internationally, as educators and parents we need to turn our attention to how video games are being understood and used in informal and formal settings. Serious games have developed as a genre of video games marketed for educating youth about a range of world issues. At face value this…

  14. The differential role of HTRA1 in HPV-positive and HPV-negative cervical cell line proliferation

    International Nuclear Information System (INIS)

    Stuqui, Bruna; Conceição, André Luis Giacometti; Termini, Lara; Sichero, Laura; Villa, Luisa Lina; Rahal, Paula; Calmon, Marília de Freitas

    2016-01-01

    High-risk human papillomaviruses (HPVs) are strongly associated with the development of some malignancies. The E6 and E7 viral oncoproteins are the primary proteins responsible for cell homeostasis alteration and immortalization. Furthermore, the E6 protein from high-risk HPVs can interact with the PDZ (PSD-90/Dlg/ZO-1) domains of cellular proteins, triggering cell transformation. One protein that is associated with pathological conditions and has a PDZ domain is the protease HTRA1 (high temperature requirement 1). This protein is poorly expressed in some cancers, suggesting a tumor suppressor role. The aim of this study was to evaluate the effect of HTRA1 overexpression in HPV16-positive (CasKi) and HPV-negative (C33) cervical cell lines. The cells were transfected with a vector containing the HTRA1 ORF or an empty vector. HTRA1 overexpression was confirmed by qRT-PCR. The cells were subjected to cell proliferation, colony formation, apoptosis and cell cycle assays. C33 cells expressing HTRA1 grew significantly fewer colonies and showed less proliferation than cells without HTRA1 expression. In contrast, in the CasKi cells overexpressing HTRA1, there was an increase in the cell growth rate and in the colonies density compared to cells expressing low levels of HTRA1. An apoptosis assay showed that HTRA1 does not interfere with the apoptosis rate in these cells. A cell cycle immunofluorescence assay revealed more CasKi cells overexpressing HTRA1 in the S phase and more C33 HTRA1-transfected cells in the G0/G1 phase, suggesting that HTRA1 plays different roles in the cell cycle progression of these cells. HTRA1 overexpression prevents cell proliferation in the HPV-negative cell line and increases cell proliferation in the HPV-positive cell line. Although the E6/HTRA1 interaction has already been described in the literature, more studies are required to confirm whether the present functional findings are a result of this interaction

  15. Positive solutions of three-point boundary-value problems for p-Laplacian singular differential equations

    Directory of Open Access Journals (Sweden)

    George N. Galanis

    2005-10-01

    Full Text Available In this paper we prove the existence of positive solutions for the three-point singular boundary-value problem$$ -[phi _{p}(u']'=q(tf(t,u(t,quad 0

  16. The whole is not the sum of its parts: Specific types of positive affect influence sleep differentially.

    Science.gov (United States)

    Pressman, Sarah D; Jenkins, Brooke N; Kraft-Feil, Tara L; Rasmussen, Heather; Scheier, Michael F

    2017-08-01

    Given the known detrimental effects of poor sleep on an array of psychological and physical health processes, it is critical to understand the factors that protect sleep, especially during times of stress when sleep particularly suffers. Positive affect (PA) arises as a variable of interest given its known associations with health and health behaviors and its ability to buffer stress. In 2 studies, we examined which types of PA (distinguished by arousal level and trait/state measurement) were most beneficial for sleep and whether these associations varied depending on the stress context. In Study 1, college students (N = 99) reported on their PA and sleep during the week of a major exam. In Study 2, 2 weeks of daily PA and sleep data were collected during a period with no examinations in a similar sample of students (N = 83). Results indicated that high trait vigor was tied to better sleep efficiency and quality, especially during high stress. Trait calm was generally unhelpful to sleep, and was related negatively to sleep duration. State calm, on the other hand, interacted with stress in Study 2 to predict more efficient day-to-day sleep on days with higher average stress. These findings illustrate the importance of considering arousal level, affect duration, and the stress context in studies of PA and health. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  17. Global Games

    NARCIS (Netherlands)

    van Bottenburg, Maarten

    2001-01-01

    Why is soccer the sport of choice in South America, while baseball has soared to popularity in the Carribean? How did cricket become India's national sport, while China is a stronghold of table tennis? In Global Games, Maarten van Bottenburg asserts that it is the 'hidden competition' of social and

  18. Urban Games

    DEFF Research Database (Denmark)

    Nielsen, Rune; Løssing, Tobias

    2004-01-01

    Games, er ikke produktudvikling i traditionel forstand, men derimod en reflekteret designproces, der forsøger at optage spilteoretiske og HCI-relaterede problemstillinger. I denne artikel vil vi koncentrere os om udvalgte principielle overvejelser i udviklingen af især forhandlings- og debatspil, som...

  19. Gaming conservation

    NARCIS (Netherlands)

    Fletcher, Robert

    2017-01-01

    This article explores the role of digital (video and computer) games in the rise of what Büscher (2014) calls "nature 2.0": new web-related media that allow users to move beyond passive voyeurism to actively "co-create" or "prosume" the images and processes promoted by organizations committed to

  20. An Overview of Structural Characteristics in Problematic Video Game Playing.

    Science.gov (United States)

    Griffiths, Mark D; Nuyens, Filip

    2017-01-01

    There are many different factors involved in how and why people develop problems with video game playing. One such set of factors concerns the structural characteristics of video games (i.e., the structure, elements, and components of the video games themselves). Much of the research examining the structural characteristics of video games was initially based on research and theorizing from the gambling studies field. The present review briefly overviews the key papers in the field to date. The paper examines a number of areas including (i) similarities in structural characteristics of gambling and video gaming, (ii) structural characteristics in video games, (iii) narrative and flow in video games, (iv) structural characteristic taxonomies for video games, and (v) video game structural characteristics and game design ethics. Many of the studies carried out to date are small-scale, and comprise self-selected convenience samples (typically using self-report surveys or non-ecologically valid laboratory experiments). Based on the small amount of empirical data, it appears that structural features that take a long time to achieve in-game are the ones most associated with problematic video game play (e.g., earning experience points, managing in-game resources, mastering the video game, getting 100% in-game). The study of video games from a structural characteristic perspective is of benefit to many different stakeholders including academic researchers, video game players, and video game designers, as well as those interested in prevention and policymaking by making the games more socially responsible. It is important that researchers understand and recognize the psycho-social effects and impacts that the structural characteristics of video games can have on players, both positive and negative.

  1. [Lecture Games] Python programming game

    OpenAIRE

    Johnsen, Andreas Lyngstad; Ushakov, Georgy

    2011-01-01

    Pythia is a programming game that allows the player to change pieces of theirenvironment through use of the programming language Python. The idea is that thegame could be used as a part of teaching simple programming to first year universitystudents. The game should be fun enough for the students to keep playing, teachenough for it to earn a place as a teaching tool, and it should be usable by allstudents. It should also be possible for a teacher to create their own content for theg...

  2. D1 and D2 Inhibitions of the Soleus H-Reflex Are Differentially Modulated during Plantarflexion Force and Position Tasks.

    Directory of Open Access Journals (Sweden)

    Fernando Henrique Magalhães

    Full Text Available Presynaptic inhibition (PSI has been shown to modulate several neuronal pathways of functional relevance by selectively gating the connections between sensory inputs and spinal motoneurons, thereby regulating the contribution of the stretch reflex circuitry to the ongoing motor activity. In this study, we investigated whether a differential regulation of Ia afferent inflow by PSI may be associated with the performance of two types of plantarflexion sensoriomotor tasks. The subjects (in a seated position controlled either: 1 the force level exerted by the foot against a rigid restraint (force task, FT; or 2 the angular position of the ankle when sustaining inertial loads (position task, PT that required the same level of muscle activation observed in FT. Subjects were instructed to maintain their force/position at target levels set at ~10% of maximum isometric voluntary contraction for FT and 90° for PT, while visual feedback of the corresponding force/position signals were provided. Unconditioned H-reflexes (i.e. control reflexes and H-reflexes conditioned by electrical pulses applied to the common peroneal nerve with conditioning-to-test intervals of 21 ms and 100 ms (corresponding to D1 and D2 inhibitions, respectively were evoked in a random fashion. A significant main effect for the type of the motor task (FT vs PT (p = 0.005, η2p = 0.603 indicated that PTs were undertaken with lower levels of Ia PSI converging onto the soleus motoneuron pool. Additionally, a significant interaction between the type of inhibition (D1 vs D2 and the type of motor task (FT vs PT (p = 0.038, η2p = 0.395 indicated that D1 inhibition was associated with a significant reduction in PSI levels from TF to TP (p = 0.001, η2p = 0.731, whereas no significant difference between the tasks was observed for D2 inhibition (p = 0.078, η2p = 0.305. These results suggest that D1 and D2 inhibitions of the soleus H-reflex are differentially modulated during the performance of

  3. The Metacognitions about Online Gaming Scale: Development and psychometric properties.

    Science.gov (United States)

    Spada, Marcantonio M; Caselli, Gabriele

    2017-01-01

    Recent research has suggested that metacognitions may play a role across the spectrum of addictive behaviours. The goal of our studies was to develop the first self-report scale of metacognitions about online gaming. We conducted two studies with samples of online gamers (n=225, n=348) to test the structure and psychometric properties of the Metacognitions about Online Gaming Scale and examined its capacity to predict weekly online gaming hours and Internet addiction. Exploratory and confirmatory factor analyses supported a three-factor solution: positive metacognitions about online gaming, negative metacognitions about the uncontrollability of online gaming, and negative metacognitions about the dangers of online gaming. Internal consistency, predictive and divergent validity were acceptable. All the factors of the Metacognitions about Online Gaming Scale correlated positively with weekly online gaming hours and Internet addiction. Regression analyses showed that negative metacognitions about the uncontrollability of online gaming and levels of Internet addiction were the only significant predictors of weekly online gaming hours, and that positive metacognitions about online gaming and negative metacognitions about the uncontrollability of online gaming were the only significant predictors of Internet addiction. The Metacognitions about Online Gaming Scale was shown to possess good psychometric properties, as well as predictive and divergent validity within the populations that were tested. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. A game is a game is a game

    DEFF Research Database (Denmark)

    Jørgensen, Ida Kathrine Hammeleff

    2017-01-01

    Recently self-referentiality have occurred as a trend among game designers and have also enjoyed sporadic attention in academia. However, in academia, discussions of self-referential games often rest on proceduralist arguments and a too exclusive focus on the game object. This paper draws...... on the typology of meta-pictures developed by art historian J.W.T. Mitchell. Based on this typology, this paper discusses the notion of meta-games and suggest a broad conception of such games that includes not only the game object, but also the player and the discourse in which it is interpreted....

  5. High User Control in Game Design Elements Increases Compliance and In-game Performance in a Memory Training Game

    Science.gov (United States)

    Nagle, Aniket; Riener, Robert; Wolf, Peter

    2015-01-01

    Computer games are increasingly being used for training cognitive functions like working memory and attention among the growing population of older adults. While cognitive training games often include elements like difficulty adaptation, rewards, and visual themes to make the games more enjoyable and effective, the effect of different degrees of afforded user control in manipulating these elements has not been systematically studied. To address this issue, two distinct implementations of the three aforementioned game elements were tested among healthy older adults (N = 21, 69.9 ± 6.4 years old) playing a game-like version of the n-back task on a tablet at home for 3 weeks. Two modes were considered, differentiated by the afforded degree of user control of the three elements: user control of difficulty vs. automatic difficulty adaptation, difficulty-dependent rewards vs. automatic feedback messages, and user choice of visual theme vs. no choice. The two modes (“USER-CONTROL” and “AUTO”) were compared for frequency of play, duration of play, and in-game performance. Participants were free to play the game whenever and for however long they wished. Participants in USER-CONTROL exhibited significantly higher frequency of playing, total play duration, and in-game performance than participants in AUTO. The results of the present study demonstrate the efficacy of providing user control in the three game elements, while validating a home-based study design in which participants were not bound by any training regimen, and could play the game whenever they wished. The results have implications for designing cognitive training games that elicit higher compliance and better in-game performance, with an emphasis on home-based training. PMID:26635681

  6. High User Control in Game Design Elements Increases Compliance and In-game Performance in a Memory Training Game.

    Science.gov (United States)

    Nagle, Aniket; Riener, Robert; Wolf, Peter

    2015-01-01

    Computer games are increasingly being used for training cognitive functions like working memory and attention among the growing population of older adults. While cognitive training games often include elements like difficulty adaptation, rewards, and visual themes to make the games more enjoyable and effective, the effect of different degrees of afforded user control in manipulating these elements has not been systematically studied. To address this issue, two distinct implementations of the three aforementioned game elements were tested among healthy older adults (N = 21, 69.9 ± 6.4 years old) playing a game-like version of the n-back task on a tablet at home for 3 weeks. Two modes were considered, differentiated by the afforded degree of user control of the three elements: user control of difficulty vs. automatic difficulty adaptation, difficulty-dependent rewards vs. automatic feedback messages, and user choice of visual theme vs. no choice. The two modes ("USER-CONTROL" and "AUTO") were compared for frequency of play, duration of play, and in-game performance. Participants were free to play the game whenever and for however long they wished. Participants in USER-CONTROL exhibited significantly higher frequency of playing, total play duration, and in-game performance than participants in AUTO. The results of the present study demonstrate the efficacy of providing user control in the three game elements, while validating a home-based study design in which participants were not bound by any training regimen, and could play the game whenever they wished. The results have implications for designing cognitive training games that elicit higher compliance and better in-game performance, with an emphasis on home-based training.

  7. Toward Understanding the Potential of Games for Learning: Learning Theory, Game Design Characteristics, and Situating Video Games in Classrooms

    Science.gov (United States)

    Turkay, Selen; Hoffman, Daniel; Kinzer, Charles K.; Chantes, Pantiphar; Vicari, Christopher

    2014-01-01

    Researchers have argued that an effort should be made to raise teachers' and parents' awareness of the potentially positive educational benefits of playing video games (e.g., see Baek, 2008). One part of this effort should be to increase understanding of how video games can be situated within teachers' existing goals and knowledge…

  8. Spatial evolutionary games with weak selection.

    Science.gov (United States)

    Nanda, Mridu; Durrett, Richard

    2017-06-06

    Recently, a rigorous mathematical theory has been developed for spatial games with weak selection, i.e., when the payoff differences between strategies are small. The key to the analysis is that when space and time are suitably rescaled, the spatial model converges to the solution of a partial differential equation (PDE). This approach can be used to analyze all [Formula: see text] games, but there are a number of [Formula: see text] games for which the behavior of the limiting PDE is not known. In this paper, we give rules for determining the behavior of a large class of [Formula: see text] games and check their validity using simulation. In words, the effect of space is equivalent to making changes in the payoff matrix, and once this is done, the behavior of the spatial game can be predicted from the behavior of the replicator equation for the modified game. We say predicted here because in some cases the behavior of the spatial game is different from that of the replicator equation for the modified game. For example, if a rock-paper-scissors game has a replicator equation that spirals out to the boundary, space stabilizes the system and produces an equilibrium.

  9. Adjusting game difficulty level through Formal Concept Analysis

    Science.gov (United States)

    Gómez-Martín, Marco A.; Gómez-Martín, Pedro P.; Gonzâlez-Calero, Pedro A.; Díaz-Agudo, Belén

    In order to reach as many players as possible, videogames usually allow the user to choose the difficulty level. To do it, game designers have to decide the values that some game parameters will have depending on that decision. In simple videogames this is almost trivial: minesweeper is harder with longer board sizes and number of mines. In more complex games, game designers may take advantage of data mining to establish which of all the possible parameters will affect positively to the player experience. This paper describes the use of Formal Concept Analysis to help to balance the game using the logs obtained in the tests made prior the release of the game.

  10. Evaluating Existing Strategies to Limit Video Game Playing Time.

    Science.gov (United States)

    Davies, Bryan; Blake, Edwin

    2016-01-01

    Public concern surrounding the effects video games have on players has inspired a large body of research, and policy makers in China and South Korea have even mandated systems that limit the amount of time players spend in game. The authors present an experiment that evaluates the effectiveness of such policies. They show that forcibly removing players from the game environment causes distress, potentially removing some of the benefits that games provide and producing a desire for more game time. They also show that, with an understanding of player psychology, playtime can be manipulated without significantly changing the user experience or negating the positive effects of video games.

  11. Advances in dynamic and mean field games theory, applications, and numerical methods

    CERN Document Server

    Viscolani, Bruno

    2017-01-01

    This contributed volume considers recent advances in dynamic games and their applications, based on presentations given at the 17th Symposium of the International Society of Dynamic Games, held July 12-15, 2016, in Urbino, Italy. Written by experts in their respective disciplines, these papers cover various aspects of dynamic game theory including mean-field games, stochastic and pursuit-evasion games, and computational methods for dynamic games. Topics covered include Pedestrian flow in crowded environments Models for climate change negotiations Nash Equilibria for dynamic games involving Volterra integral equations Differential games in healthcare markets Linear-quadratic Gaussian dynamic games Aircraft control in wind shear conditions Advances in Dynamic and Mean-Field Games presents state-of-the-art research in a wide spectrum of areas. As such, it serves as a testament to the continued vitality and growth of the field of dynamic games and their applications. It will be of interest to an interdisciplinar...

  12. Defining Game Mechanics

    DEFF Research Database (Denmark)

    Sicart (Vila), Miguel Angel

    2008-01-01

    This article defins game mechanics in relation to rules and challenges. Game mechanics are methods invoked by agents for interacting with the game world. I apply this definition to a comparative analysis of the games Rez, Every Extend Extra and Shadow of the Colossus that will show the relevance...... of a formal definition of game mechanics. Udgivelsesdato: Dec 2008...

  13. Models and games

    NARCIS (Netherlands)

    Väänänen, J.

    2011-01-01

    This gentle introduction to logic and model theory is based on a systematic use of three important games in logic: the semantic game; the Ehrenfeucht–Fraïssé game; and the model existence game. The third game has not been isolated in the literature before but it underlies the concepts of Beth

  14. Teaching Using Computer Games

    Science.gov (United States)

    Miller, Lee Dee; Shell, Duane; Khandaker, Nobel; Soh, Leen-Kiat

    2011-01-01

    Computer games have long been used for teaching. Current reviews lack categorization and analysis using learning models which would help instructors assess the usefulness of computer games. We divide the use of games into two classes: game playing and game development. We discuss the Input-Process-Outcome (IPO) model for the learning process when…

  15. Alena Lidzhieva, About Games

    OpenAIRE

    Dovurkaev, Karu; Churyumov, Anton

    2015-01-01

    Alena talks about traditional games, including khorma khotn, tsagan monda, mongn bus, nyarn shinj, and games played with ankle bones. Tsagan monda was a game played at night by several people. The rule is simple: A ball made of white cow skin is pushed into a hole. Games with ankle bones were reserved only for boys. Girls did not play such games. Arcadia

  16. Uptake of 131-I in maxillary bones mimicking salivary glands. False- positive images in patients with differentiated thyroid carcinoma (DTC )

    International Nuclear Information System (INIS)

    Degrossi, Osvaldo J.; Degrossi, E.B.; Levi de Cabrejas, Mariana

    2008-01-01

    with the intensity of the administered activity of radioiodine, the previous condition of dental integrity and in patients living in the interior of our country in zones of 'bad' water containing tracers of arsenic and fluorine. In 13 patients submitted to intense treatment of dental problems posterior WBS showed a decrease of the positive maxilla areas or they were not found. The presence of metastasis in the active maxilla area was in all cases negative. Our observations confirm that radioiodine is deposited in maxillary bone in relation of dental lesions and that this 131-I move in a very slow place. This mechanism of fixation has to be determined. We fully recommended taking into account the existence of dental illness or incomplete dental treatments when the administration of higher activities than 3.7 GBq (150 mCi). (author) [es

  17. Coevolution of Artificial Agents Using Evolutionary Computation in Bargaining Game

    Directory of Open Access Journals (Sweden)

    Sangwook Lee

    2015-01-01

    Full Text Available Analysis of bargaining game using evolutionary computation is essential issue in the field of game theory. This paper investigates the interaction and coevolutionary process among heterogeneous artificial agents using evolutionary computation (EC in the bargaining game. In particular, the game performance with regard to payoff through the interaction and coevolution of agents is studied. We present three kinds of EC based agents (EC-agent participating in the bargaining game: genetic algorithm (GA, particle swarm optimization (PSO, and differential evolution (DE. The agents’ performance with regard to changing condition is compared. From the simulation results it is found that the PSO-agent is superior to the other agents.

  18. Value of 201Tl imaging in predicting therapeutic 131I uptake in patients with thyroglobulin-positive but 131I scan-negative differentiated thyroid carcinoma

    International Nuclear Information System (INIS)

    Conlu, R.A.O.; Obaldo, J.M.

    2004-01-01

    Background: Serum thyroglobulin assay and 131Iodine (1311) whole body scan are considered complementary in detecting malignant thyroid tissue or metastases. A large number of patients, however, are encountered presenting with scan-negative, thyroglobulin-positive differentiated thyroid carcinoma posing a dilemma in therapeutic management. One of the first alternative scanning agents to be employed is 201Thallium (201Tl). Recent studies have demonstrated its usefulness in identifying lesions that are not visualized with traditional 131I whole body scan. It is not clear, however, whether 201Tl scan helps in the decision-making for subsequent 131I therapy. This study was conducted to determine if 201Tl scan can predict therapeutic 131I uptake and to define the clinical role of 201Tl scanning in these patients. Methods and results: A total of 12 patients (20-63 y/o), 5 males and 7 females, underwent surgery for differentiated thyroid cancer and all had serum thyroglobulin values above 10 ng/ml and normal TPO autoantibodies. Pre-therapy 131I scan using 111 MBq (3mCi) of 131I were obtained. As required for inclusion, all patients had negative pre-therapy scan and negative TPO autoantibody results and underwent 20lTl scanning within 3 weeks. All patients were given 131I therapy (3.7-5.5 GBq or 100-150 mCi) between one to two months after 201Tl scanning. Within a week after therapy, all patients underwent whole body 1311 scanning. 201Tl imaging demonstrated thyroid remnants in 9 out of 12 patients having positive 201Tl scan but negative pre-therapy 1311 scan. However, only 2 of the positive 201Tl scans showed 131I uptake post-therapy (positive predictive value of 20%). None of the subjects presented with a negative 201Tl scan and a positive post-therapy 131I scan. Conclusion: Our study suggests that evidence of remnants or metastases on 201Tl scanning may be an inappropriate basis for the decision to proceed with 131I therapy. The role of 20lTl imaging in this subset of

  19. Heterogeneous game resource distributions promote cooperation in spatial prisoner's dilemma game

    Science.gov (United States)

    Cui, Guang-Hai; Wang, Zhen; Yang, Yan-Cun; Tian, Sheng-Wen; Yue, Jun

    2018-01-01

    In social networks, individual abilities to establish interactions are always heterogeneous and independent of the number of topological neighbors. We here study the influence of heterogeneous distributions of abilities on the evolution of individual cooperation in the spatial prisoner's dilemma game. First, we introduced a prisoner's dilemma game, taking into account individual heterogeneous abilities to establish games, which are determined by the owned game resources. Second, we studied three types of game resource distributions that follow the power-law property. Simulation results show that the heterogeneous distribution of individual game resources can promote cooperation effectively, and the heterogeneous level of resource distributions has a positive influence on the maintenance of cooperation. Extensive analysis shows that cooperators with large resource capacities can foster cooperator clusters around themselves. Furthermore, when the temptation to defect is high, cooperator clusters in which the central pure cooperators have larger game resource capacities are more stable than other cooperator clusters.

  20. Engagement states and learning from educational games.

    Science.gov (United States)

    Deater-Deckard, Kirby; Chang, Mido; Evans, Michael E

    2013-01-01

    Children's and adolescents' cognitive, affective, and behavioral states of engagement enhance or impede enjoyment of, and performance with, educational games. We propose a comprehensive model of engagement states and apply it to research on educational game development and research on the role of various aspects of engagement on game play and learning. Emphasis is placed on individual differences in attention, memory, motor speed and control, persistence, and positive and negative affect (approach/avoidance), and how these pertain to social cognitions regarding mathematics achievement. Our challenge is to develop educational games that are effective for a wide variety of student engagement states. Copyright © 2013 Wiley Periodicals, Inc., A Wiley Company.

  1. Perspectives on Video Games as Art

    OpenAIRE

    Bourgonjon, Jeroen; Vandermeersche, Geert; Rutten, Kris

    2017-01-01

    In their article "Perspectives on Video Games as Art" Jeroen Bourgonjon, Geert Vndermeer­sche, and Kris Rutten engage in discussing whether or not video games can be considered a form of art. Although this question has already been discussed elaborately, the debate is guided by many differ­ent and often conflicting positions. The aim of this article is to revisit this debate by mapping out a range of perspectives on video games as art. The authors explore the relation between games and differ...

  2. Collective Learning in Games through Social Networks

    NARCIS (Netherlands)

    Kosterman, S.; Gierasimczuk, N.; Armentano, M.G.; Monteserin, A.; Tang, J.; Yannibelli, V.

    2015-01-01

    This paper argues that combining social networks communication and games can positively influence the learning behavior of players. We propose a computational model that combines features of social network learning (communication) and game-based learning (strategy reinforcement). The focus is on

  3. How Gamers Manage Aggression: Situating Skills in Collaborative Computer Games

    Science.gov (United States)

    Bennerstedt, Ulrika; Ivarsson, Jonas; Linderoth, Jonas

    2012-01-01

    In the discussion on what players learn from digital games, there are two major camps in clear opposition to each other. As one side picks up on negative elements found in games the other side focuses on positive aspects. While the agendas differ, the basic arguments still depart from a shared logic: that engagement in game-related activities…

  4. The new gatekeepers: the occupational ideology of game journalism

    NARCIS (Netherlands)

    Nieborg, D.B.; Sihvonen, T.

    2009-01-01

    This paper will contextualize the occupational ideology of game journalism by providing a brief introduction to the political economy of game publications. The role of various industry actors (e.g. game publishers, PR agents and brand managers) will be positioned against those of the peripheral

  5. A serious game for COPD patients to perform physiotherapeutic exercises

    NARCIS (Netherlands)

    Tabak, Monique; Marin Perianu, Raluca; Hermens, Hermanus J.

    The goal of this research was 1) to investigate the usability of the Orange Submarine game, and 2) to explore the changes in saturation and pulse rate in COPD patients while playing the game. The game was positively received by the patients and could provide a new fun way for performing exercises,

  6. Children and Electronic Games in the United States.

    Science.gov (United States)

    Funk, Jeanne B.; Bermann, Julie N.; Buchman, Debra D.

    1997-01-01

    Reports video game playing demographics. Reviews the literature on video game health hazards and positive health applications; cutting-edge applications in education and controversies about learning; and effects on personality. Discusses laboratory and survey research on the effects of video games violence. Considers whether some children may be…

  7. Game changing - tracing the positions, strategies and interaction modes of the German Länder towards the (ever expanding?) European Union

    DEFF Research Database (Denmark)

    Jensen, Mads Christian Dagnis

    2014-01-01

    This article investigates how the positions, strategies and modes of interaction of the German Länder have changed over time in response to the process of Europeanization. By applying the method of process tracing within a theoretical framework of rational choice institutionalism, the article...... resulted in a more sceptical attitude of the Länder towards (the perceived ever expanding) European Union....

  8. Towards gaze-controlled platform games

    DEFF Research Database (Denmark)

    Muñoz, Jorge; Yannakakis, Georgios N.; Mulvey, Fiona

    2011-01-01

    This paper introduces the concept of using gaze as a sole modality for fully controlling player characters of fast-paced action computer games. A user experiment is devised to collect gaze and gameplay data from subjects playing a version of the popular Super Mario Bros platform game. The initial...... analysis shows that there is a rather limited grid around Mario where the efficient player focuses her attention the most while playing the game. The useful grid as we name it, projects the amount of meaningful visual information a designer should use towards creating successful player character...... controllers with the use of artificial intelligence for a platform game like Super Mario. Information about the eyes' position on the screen and the state of the game are utilized as inputs of an artificial neural network, which is trained to approximate which keyboard action is to be performed at each game...

  9. Neural activity to intense positive versus negative stimuli can help differentiate bipolar disorder from unipolar major depressive disorder in depressed adolescents: a pilot fMRI study.

    Science.gov (United States)

    Diler, Rasim Somer; de Almeida, Jorge Renner Cardoso; Ladouceur, Cecile; Birmaher, Boris; Axelson, David; Phillips, Mary

    2013-12-30

    Failure to distinguish bipolar depression (BDd) from the unipolar depression of major depressive disorder (UDd) in adolescents has significant clinical consequences. We aimed to identify differential patterns of functional neural activity in BDd versus UDd and employed two (fearful and happy) facial expression/ gender labeling functional magnetic resonance imaging (fMRI) experiments to study emotion processing in 10 BDd (8 females, mean age=15.1 ± 1.1) compared to age- and gender-matched 10 UDd and 10 healthy control (HC) adolescents who were age- and gender-matched to the BDd group. BDd adolescents, relative to UDd, showed significantly lower activity to both intense happy (e.g., insula and temporal cortex) and intense fearful faces (e.g., frontal precentral cortex). Although the neural regions recruited in each group were not the same, both BDd and UDd adolescents, relative to HC, showed significantly lower neural activity to intense happy and mild happy faces, but elevated neural activity to mild fearful faces. Our results indicated that patterns of neural activity to intense positive and negative emotional stimuli can help differentiate BDd from UDd in adolescents. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  10. Proliferation and chondrogenic differentiation of CD105-positive enriched rat synovium-derived mesenchymal stem cells in three-dimensional porous scaffolds

    International Nuclear Information System (INIS)

    Qi Jun; Chen Anmin; You Hongbo; Li Kunpeng; Zhang Di; Guo Fengjing

    2011-01-01

    Stem cell-based tissue engineering has provided an alternative strategy to treat cartilage lesions, and synovium-derived mesenchymal stem cells (SMSCs) are considered as a promising cell source for cartilage repair. In this study, the SMSCs were isolated from rat synovium, and CD105-positive (CD105 + ) cells were enriched using magnetic activated cell sorting. Sorted cells were subsequently seeded onto the chitosan-alginate composite three-dimensional (3D) porous scaffolds and cultured in chondrogenic culture medium in the presence of TGF-β 3 and BMP-2 for 2 weeks in vitro. After 2 weeks in culture, scanning electron microscopy results showed that cells attached and proliferated well on scaffolds, and secreted extracellular matrix were also observed. From day 7 to day 14, the total DNA and glucosaminoglycan content of the cells cultured in scaffolds were found to have increased significantly, and cell cycle analyses revealed that the percentage of cells in the S and G2/M phases increased and the percentage of cells in the G0/G1 phase decreased. Compared with non-sorted cells, the sorted cells cultured in scaffolds underwent more chondrogenic differentiation, as evidenced by higher expression of type II collagen and Sox9 at the protein and mRNA levels. The results suggest that CD105 + enriched SMSCs may be a potential cell source for cartilage tissue engineering, and the chitosan-alginate composite 3D porous scaffold could provide a favorable microenvironment for supporting proliferation and chondrogenic differentiation of cells.

  11. Authoring of digital games via card games

    DEFF Research Database (Denmark)

    Valente, Andrea; Marchetti, Emanuela

    2014-01-01

    Literature and previous studies show that creative play is easy to emerge when children interact with tangible, low-tech toys and games than with digital games. This paradoxical situation is linked to the long-standing problem of end-users (or players) authoring of digital contents and systems. We...... are to show how card games can represent digital games, how playful play can emerge in card games and digital games, and to begin defining a new way to express game behavior without the use of universal programming languages....... propose a new scenario in which trading card games help making sense and re-design computer games, to support players express themselves aesthetically and in a highly creative way. Our aim is to look for a middle ground between players becoming programmers and simply editing levels. The main contributions...

  12. Is Immersion of Any Value? Whether, and to What Extent, Game Immersion Experience during Serious Gaming Affects Science Learning

    Science.gov (United States)

    Cheng, Meng-Tzu; Lin, Yu-Wen; She, Hsiao-Ching; Kuo, Po-Chih

    2017-01-01

    Many studies have shown the positive impact of serious gaming on learning outcomes, but few have explored the relationships between game immersion and science learning. Accordingly, this study was conducted to investigate the effectiveness of learning by playing, as well as the dynamic process of game immersion experiences, and to further identify…

  13. Flow Game

    DEFF Research Database (Denmark)

    Olsen, Jesper Lind

    2003-01-01

    Flow Game er et dialogspil, der kan bruges som ledelsesværktøj, ledertræning, samtaletræning, coachingtræning og ideudvikling m.m. Gennem dilemmakort provokeres en dialog og teori-U inspireret afklaring- og udviklingsproces, hvor der enten arbejdes på en gruppes eller et individs vision/innovatio......Flow Game er et dialogspil, der kan bruges som ledelsesværktøj, ledertræning, samtaletræning, coachingtræning og ideudvikling m.m. Gennem dilemmakort provokeres en dialog og teori-U inspireret afklaring- og udviklingsproces, hvor der enten arbejdes på en gruppes eller et individs vision...

  14. The Game of Tri

    Science.gov (United States)

    Haggard, Gary; Schonberger, Ann Koch

    1977-01-01

    The paper-and-pencil game "Tri" is described. The authors argue that students gain logical skills by playing the game, and that the game lends itself to the introduction of diverse mathematical ideas. (SD)

  15. Play the MRI Game

    Science.gov (United States)

    ... Teachers' Questionnaire MRI Play MRI the Magnetic Miracle Game About the game In the MRI imaging technique, strong magnets and ... last will in Paris. Play the Blood Typing Game Try to save some patients and learn about ...

  16. Play the Electrocardiogram Game

    Science.gov (United States)

    ... and Work Teachers' Questionnaire Electrocardiogram Play the ECG Game About the game ECG is used for diagnosing heart conditions by ... last will in Paris. Play the Blood Typing Game Try to save some patients and learn about ...

  17. Understanding the effects of violent video games on violent crime

    OpenAIRE

    Cunningham, A. Scott; Engelstätter, Benjamin; Ward, Michael R.

    2011-01-01

    Psychological studies invariably find a positive relationship between violent video game play and aggression. However, these studies cannot account for either aggressive effects of alternative activities video game playing substitutes for or the possible selection of relatively violent people into playing violent video games. That is, they lack external validity. We investigate the relationship between the prevalence of violent video games and violent crimes. Our results are consistent with t...

  18. ENHANCING ENGLISH LANGUAGE LEARNERS’ MOTIVATION THROUGH ONLINE GAMES

    OpenAIRE

    Nataliia V. Iaremenko

    2017-01-01

    In this article, we examine the potentials of online games which teachers can employ in order to motivate their students and summarize the positive effects of playing learning games. The study addresses the question of how gamified learning is applicable to learning English as a second language. The other research questions refer to the reasons that make language learners want to play a learning game and the influence of particular game elements onto players. All of these questions are invest...

  19. Coaching to vision versus coaching to improvement needs: a preliminary investigation on the differential impacts of fostering positive and negative emotion during real time executive coaching sessions.

    Science.gov (United States)

    Howard, Anita R

    2015-01-01

    Drawing on intentional change theory (ICT; Boyatzis, 2006), this study examined the differential impact of inducing coaching recipients' vision/positive emotion versus improvement needs/negative emotion during real time executive coaching sessions. A core aim of the study was to empirically test two central ICT propositions on the effects of using the coached person's Positive Emotional Attractor (vision/PEA) versus Negative Emotional Attractor (improvement needs/NEA) as the anchoring framework of a onetime, one-on-one coaching session on appraisal of 360° feedback and discussion of possible change goals. Eighteen coaching recipients were randomly assigned to two coaching conditions, the coaching to vision/PEA condition and the coaching to improvement needs/NEA condition. Two main hypotheses were tested. Hypothesis1 predicted that participants in the vision/PEA condition would show higher levels of expressed positive emotion during appraisal of 360° feedback results and discussion of change goals than recipients in the improvement needs/NEA condition. Hypothesis2 predicted that vision/PEA participants would show lower levels of stress immediately after the coaching session than improvement needs/NEA participants. Findings showed that coaching to vision/the PEA fostered significantly lower levels of expressed negative emotion and anger during appraisal of 360° feedback results as compared to coaching to improvements needs/the NEA. Vision-focused coaching also fostered significantly greater exploration of personal passions and future desires, and more positive engagement during 360° feedback appraisal. No significant differences between the two conditions were found in emotional processing during discussion of change goals or levels of stress immediately after the coaching session. Current findings suggest that vision/PEA arousal versus improvement needs/NEA arousal impact the coaching process in quite different ways; that the coach's initial framing of the

  20. Negotiation Games

    OpenAIRE

    Philipp Hoffmann

    2015-01-01

    Negotiations, a model of concurrency with multi party negotiation as primitive, have been recently introduced by J. Desel and J. Esparza. We initiate the study of games for this model. We study coalition problems: can a given coalition of agents force that a negotiation terminates (resp. block the negotiation so that it goes on forever)?; can the coalition force a given outcome of the negotiation? We show that for arbitrary negotiations the problems are EXPTIME-complete. Then we show that for...

  1. Sovereignty Games

    DEFF Research Database (Denmark)

    Gammeltoft-Hansen, Thomas

    This book offers an in-depth examination of the strategic use of State sovereignty in contemporary European and international affairs and the consequences of this for authority relations in Europe and beyond. It suggests a new approach to the study of State sovereignty, proposing to understand th...... the use of sovereignty as games where States are becoming more instrumental in their claims to sovereignty and skilled in adapting it to the challenges that they face....

  2. Board game

    International Nuclear Information System (INIS)

    Brennan, N.S.

    1982-01-01

    A board game comprises a board, a number of counters and two dice. The board is marked to provide a central area, representing the nucleus of an atom, and six or more annular rings extending concentrically around the central area, the rings being divided into 2,8,18,32,48 and 72 squares. Each ring represents an electron shell, and some of the squares are numbered, the number representing the atomic number of different elements. (author)

  3. Somatotipo en futbolistas semiprofesionales clasificados por su posición de juego. Somatotype of semiprfesional soccer players classified by their position in the game.

    Directory of Open Access Journals (Sweden)

    Lidia Guillermina de León Fierro

    2007-10-01

    Full Text Available ResumenObjetivo. Identificar el somatotipo antropométrico de jugadores de fútbol pertenecientes al equipo Patriots de El Paso TX, USA, clasificados por su posición en el terreno de juego y obtener el (SAD por sus siglas en inglés definiéndola como la distancia entre 2 somatopuntos, así como también determinar la distancia actitudinal media (SAM por sus siglas en inglés que se refiere a la media de la dispersión que un grupo de puntos del somatotipo tridimensional con respecto a su promedio. Método. Participaron 15 jugadores de fútbol del Club Patriots de El Paso, TX., clasificados por posición en porteros (POR, medios (MED y delanteros (DEL. Se les determinó el Somatotipo a partir de 10 variables antropométricas Heath & Carter (1990. Se calculó el SAD para cada jugador, también se determinó SAM para cada posición de juego y equipo en general. Resultados. El uso de estadística descriptiva, ANOVA, t de Student indicó que los jugadores tienen características muy similares independientemente de su posición en el campo de juego. El SAD entre POR y DEL fue mayor a 1. El SAD entre Club Patriots y otros equipos mundiales fue menor a 1, El SAM entre el grupo de estudio comparado con equipos mundiales fue menor a 1 Conclusiones. El físico de los jugadores mostró un bajo nivel de especialización, por su ubicación en el campo de juego. AbstractObjective. The aim of this investigation was to examine the relationship between anthropometric somatotype of semi-professional soccer players from Premier Development League United States team and their position in the field. Methods. Somatotype attitudinal distance (SAD and somatotype attitudinal mean (SAM were calculated for fifteen players. The study group included goalkeepers, midfielders, and forwards. Anthropometric somatotype was determined from ten variables Heath & Carter (1990. SAD was calculated for each individual player, and SAM was obtained both for each position and the whole

  4. Games at work: the recreational use of computer games during working hours.

    Science.gov (United States)

    Reinecke, Leonard

    2009-08-01

    The present study investigated the recreational use of video and computer games in the workplace. In an online survey, 833 employed users of online casual games reported on their use of computer games during working hours. The data indicate that playing computer games in the workplace elicits substantial levels of recovery experience. Recovery experience associated with gameplay was the strongest predictor for the use of games in the workplace. Furthermore, individuals with higher levels of work-related fatigue reported stronger recovery experience during gameplay and showed a higher tendency to play games during working hours than did persons with lower levels of work strain. Additionally, the social situation at work was found to have a significant influence on the use of games. Persons receiving less social support from colleagues and supervisors played games at work more frequently than did individuals with higher levels of social support. Furthermore, job control was positively related to the use of games at work. In sum, the results of the present study illustrate that computer games have a significant recovery potential. Implications of these findings for research on personal computer use during work and for games research in general are discussed.

  5. A game magically circling

    DEFF Research Database (Denmark)

    Ejsing-Duun, Stine

    2011-01-01

    This chapter analyses the relationship between players, the game world, and the ordinary world in alternative reality games (ARGs) and location-based games (LBGs). These games use technology to create a game world in the everyday scene. The topic of this chapter is the concept of the 'magic circle......', which defines the relationship between play and the ordinary world, and how this concept relates to a new kind of game....

  6. Computer Games and Instruction

    Science.gov (United States)

    Tobias, Sigmund, Ed.; Fletcher, J. D., Ed.

    2011-01-01

    There is intense interest in computer games. A total of 65 percent of all American households play computer games, and sales of such games increased 22.9 percent last year. The average amount of game playing time was found to be 13.2 hours per week. The popularity and market success of games is evident from both the increased earnings from games,…

  7. PROOF BY GAMES

    Science.gov (United States)

    2016-03-01

    Robot, in order to explore automated strategies ). The Game Client receives level data from the Game Server and implements the game as the player sees...formal verification domain. If formal verification problems could be turned into entertaining video games , those games could be crowd- sourced to a large...style gates that would destroy the Circuitbots. As the game evolved we found no good strategies for constraint ordering that worked significantly

  8. Mechanizing Exploratory Game Design

    OpenAIRE

    Smith, Adam Marshall

    2012-01-01

    Game design is an art form that deals with inherently interactive artifacts. Game designers craft games (assembled from rule systems and content), but they really seek to manipulate play: the interaction between games and players. When developing new games that are similar to past games, a designer may rely on previous experience with related designs and relatively easy access to players familiar with conventional design choices. When exploratorily venturing into uncharted territory, uncoveri...

  9. Dutch children and parents' views on active and non-active video gaming.

    Science.gov (United States)

    De Vet, Emely; Simons, Monique; Wesselman, Maarten

    2014-06-01

    Active video games that require whole body movement to play the game may be an innovative health promotion tool to substitute sedentary pastime with more active time and may therefore contribute to children's health. To inform strategies aimed at reducing sedentary behavior by replacing non-active by active gaming, opinions about active and non-active video games are explored among 8- to 12-year-old children and their parents. Six qualitative, semi-structured focus groups were held with 8- to 12-year-old children (n = 46) and four with their parents (n = 19) at three different primary schools in The Netherlands. The focus groups with children discussed game preferences, gaming context and perceived game-related parenting. The focus groups with parents addressed considerations in purchasing video games, perceived positive and negative consequences of gaming, and game-related parenting. Both children and their parents were very positive about active video games and preferred active games over non-active games. Active video games were considered more social than non-active video games, and active games were played more often together with friends and family than non-active video games. Parenting practices did not differ for active and non-active video games, although some parents were less strict regarding active games. Two conditions for practical implementation were met: children enjoyed active video games, and parents were willing to buy active video games. Active video games were preferred to non-active video games, illustrating that using active video games is a promising health promotion tool to reduce sedentary pastime in youth.

  10. Video game characteristics, happiness and flow as predictors of addiction among video game players: a pilot study

    OpenAIRE

    Hull, DC; Williams, GA; Griffiths, MD

    2013-01-01

    Aims:\\ud Video games provide opportunities for positive psychological experiences such as flow-like phenomena during play and general happiness that could be associated with gaming achievements. However, research has shown that specific features of game play may be associated with problematic behaviour associated with addiction-like experiences. The study was aimed at analysing whether certain structural characteristics of video games, flow, and global happiness could be predictive of video g...

  11. Game engines: a survey

    Directory of Open Access Journals (Sweden)

    A. Andrade

    2015-11-01

    Full Text Available Due to hardware limitations at the origin of the video game industry, each new game was generally coded from the ground up. Years later, from the evolution of hardware and the need for quick game development cycles, spawned the concept of game engine. A game engine is a reusable software layer allowing the separation of common game concepts from the game assets (levels, graphics, etc.. This paper surveys fourteen different game engines relevant today, ranging from the industry-level to the newcomer-friendlier ones.

  12. Games, theory and applications

    CERN Document Server

    Thomas, L C

    2011-01-01

    Anyone with a knowledge of basic mathematics will find this an accessible and informative introduction to game theory. It opens with the theory of two-person zero-sum games, two-person non-zero sum games, and n-person games, at a level between nonmathematical introductory books and technical mathematical game theory books. Succeeding sections focus on a variety of applications - including introductory explanations of gaming and meta games - that offer nonspecialists information about new areas of game theory at a comprehensible level. Numerous exercises appear with full solutions, in addition

  13. The mathematics of games

    CERN Document Server

    Beasley, John D

    2006-01-01

    ""Mind-exercising and thought-provoking.""-New ScientistIf playing games is natural for humans, analyzing games is equally natural for mathematicians. Even the simplest of games involves the fundamentals of mathematics, such as figuring out the best move or the odds of a certain chance event. This entertaining and wide-ranging guide demonstrates how simple mathematical analysis can throw unexpected light on games of every type-games of chance, games of skill, games of chance and skill, and automatic games.Just how random is a card shuffle or a throw of the dice? Is bluffing a valid poker strat

  14. Video game characteristics, happiness and flow as predictors of addiction among video game players: A pilot study.

    Science.gov (United States)

    Hull, Damien C; Williams, Glenn A; Griffiths, Mark D

    2013-09-01

    Video games provide opportunities for positive psychological experiences such as flow-like phenomena during play and general happiness that could be associated with gaming achievements. However, research has shown that specific features of game play may be associated with problematic behaviour associated with addiction-like experiences. The study was aimed at analysing whether certain structural characteristics of video games, flow, and global happiness could be predictive of video game addiction. A total of 110 video game players were surveyed about a game they had recently played by using a 24-item checklist of structural characteristics, an adapted Flow State Scale, the Oxford Happiness Questionnaire, and the Game Addiction Scale. The study revealed decreases in general happiness had the strongest role in predicting increases in gaming addiction. One of the nine factors of the flow experience was a significant predictor of gaming addiction - perceptions of time being altered during play. The structural characteristic that significantly predicted addiction was its social element with increased sociability being associated with higher levels of addictive-like experiences. Overall, the structural characteristics of video games, elements of the flow experience, and general happiness accounted for 49.2% of the total variance in Game Addiction Scale levels. Implications for interventions are discussed, particularly with regard to making players more aware of time passing and in capitalising on benefits of social features of video game play to guard against addictive-like tendencies among video game players.

  15. Video game characteristics, happiness and flow as predictors of addiction among video game players: A pilot study

    Science.gov (United States)

    Hull, Damien C.; Williams, Glenn A.; Griffiths, Mark D.

    2013-01-01

    Aims: Video games provide opportunities for positive psychological experiences such as flow-like phenomena during play and general happiness that could be associated with gaming achievements. However, research has shown that specific features of game play may be associated with problematic behaviour associated with addiction-like experiences. The study was aimed at analysing whether certain structural characteristics of video games, flow, and global happiness could be predictive of video game addiction. Method: A total of 110 video game players were surveyed about a game they had recently played by using a 24-item checklist of structural characteristics, an adapted Flow State Scale, the Oxford Happiness Questionnaire, and the Game Addiction Scale. Results: The study revealed decreases in general happiness had the strongest role in predicting increases in gaming addiction. One of the nine factors of the flow experience was a significant predictor of gaming addiction – perceptions of time being altered during play. The structural characteristic that significantly predicted addiction was its social element with increased sociability being associated with higher levels of addictive-like experiences. Overall, the structural characteristics of video games, elements of the flow experience, and general happiness accounted for 49.2% of the total variance in Game Addiction Scale levels. Conclusions: Implications for interventions are discussed, particularly with regard to making players more aware of time passing and in capitalising on benefits of social features of video game play to guard against addictive-like tendencies among video game players. PMID:25215196

  16. Establishing an Educational Game Development Model: From the Experience of Teaching Search Engine Optimization

    Science.gov (United States)

    Lui, Richard W. C.; Au, Cheuk Hang

    2018-01-01

    This article describes how different literatures have suggested the positive role of educational games in students' learning, but it can be hard to find an existing game for student learning. Some lecturers may try to develop a game for their courses, but there were not many effective models for educational board game development. The authors have…

  17. Games and Brain-Computer Interfaces: The State of the Art

    NARCIS (Netherlands)

    Reuderink, B.

    2008-01-01

    BCI gaming is a very young field; most games are proof-of-concepts. Work that compares BCIs in a game environments with traditional BCIs indicates no negative effects, or even a positive effect of the rich visual environments on the performance. The low transfer-rate of current games poses a problem

  18. Conceptualizing Cognitive Skills Developed during Video Game Play: A Case Study in Teaching Composition

    Science.gov (United States)

    Smith, Sandra Wilson

    2008-01-01

    While video games have been much maligned in the popular press, a number of scholars have begun to explore the positive side of these games, especially in terms of learning. Some critics have analyzed video games and the act of game play as complex, cultural texts. In college courses, such as composition, in which one goal is the development of…

  19. Serious Games for Health: Spielend lernen und heilen mit Computerspielen? / Serious Games for Health: Learning and healing with video games?

    Directory of Open Access Journals (Sweden)

    Sostmann, Kai

    2010-01-01

    Full Text Available Serious Games (SG are a new medium in the context of e-learning. Serious Games use the multimedial advantages of computer and video games to fulfil the didactic requirements to teach target groups in classical and new learning scenarios. Serious Games for Health (SGH can be applied in the domains of medical therapy, continuing medical education and in the fields of prevention and health promotion. From a didactic and instructional psychology perspective the impact of Serious Games is based on their integration into motivational and multimedia aspects of computer and video games from different genres in learning scenarios. Serious Games in the domain of therapy can be a meaningful endorsement to existing therapies for both patients and relatives to improve the therapeutic outcome and to foster the compliance of patients. In the field of continually medical education studies show the positive impact of Serious Games on learning outcomes. Serious Games in prevention and health promotion are mostly applied in the framework of public communication campaigns.

  20. Design of Game Space

    DEFF Research Database (Denmark)

    Kristiansen, Erik

    2011-01-01

    Playing games of any kind, from tennis to board games, it is easy to notice that games are configured in space, often using stripes or a kind of map on a board. Some games are clearly performed within this marked border, while it may be difficult to pinpoint such a visual border in a game like hide....... This makes sense, but also demands that play and non-play can be easily separated. I will examine how games make use of space, and show that the magic circle not only is a viable, though criticized, concept but should be understood as a spatial concept. In order to do this several games are examined, leading...... to introduce a spatial model of the game performance comprising a primary and secondary game space. I will show how new game genres can profit from using this model when designing new games....

  1. Differential ultrasonic indices of separation distress in the presence and absence of maternal cues in infant rats bred for high and low positive social affect.

    Science.gov (United States)

    Iacobucci, Paolo; Colonnello, Valentina; Fuchs, Thomas; D'Antuono, Laura; Panksepp, Jaak

    2013-10-01

    Preclinical models of human mood disorders commonly focus on the study of negative affectivity, without comparably stressing the role of positive affects and their ability to promote resilient coping styles. We evaluated the role of background constitutional affect of rats by studying the separation and reunion responses of infants from low and high positive affect genetic lines (i.e., differentially selected for High and Low 50 kHz ultrasonic vocalisations (USVs). Infants from Low and High 50 kHz USV breeding lines were isolated from mothers and exposed to either social (familiar or unfamiliar bedding) or neutral (clean bedding) odour cues between two short isolation periods, and tested in homeothermic and hypothermic ambient temperatures. Negative affect was estimated by monitoring separation distress calls (35-45 kHz USVs). Low Line pups called at higher rates than High Line, and their rates were stable regardless of odour cue. In contrast, High Line pups increased vocalisations during the second compared with the first isolation periods and during exposure to both familiar and unfamiliar odour cues, but not to neutral odour. Furthermore, the greatest increase in USV emission was seen in the second isolation period following exposure to the unfamiliar odour. However, both lines showed comparable elevated distress USVs to the thermal stressor. High Line animals, selected for a positive affective phenotype (50 kHz USVs), exhibited reduced separation anxiety responses in infancy, making this a promising animal model for the role of constitutional affective states in emotional responsivity and potential resilience against emotional disorders.

  2. The mediating effect of gaming motivation between psychiatric symptoms and problematic online gaming: an online survey.

    Science.gov (United States)

    Király, Orsolya; Urbán, Róbert; Griffiths, Mark D; Ágoston, Csilla; Nagygyörgy, Katalin; Kökönyei, Gyöngyi; Demetrovics, Zsolt

    2015-04-07

    The rapid expansion of online video gaming as a leisure time activity has led to the appearance of problematic online gaming (POG). According to the literature, POG is associated with different psychiatric symptoms (eg, depression, anxiety) and with specific gaming motives (ie, escape, achievement). Based on studies of alcohol use that suggest a mediator role of drinking motives between distal influences (eg, trauma symptoms) and drinking problems, this study examined the assumption that there is an indirect link between psychiatric distress and POG via the mediation of gaming motives. Furthermore, it was also assumed that there was a moderator effect of gender and game type preference based on the important role gender plays in POG and the structural differences between different game types. This study had two aims. The first aim was to test the mediating role of online gaming motives between psychiatric symptoms and problematic use of online games. The second aim was to test the moderator effect of gender and game type preference in this mediation model. An online survey was conducted on a sample of online gamers (N=3186; age: mean 21.1, SD 5.9 years; male: 2859/3186, 89.74%). The Brief Symptom Inventory (BSI), the Motives for Online Gaming Questionnaire (MOGQ), and the Problematic Online Gaming Questionnaire (POGQ) were administered to assess general psychiatric distress, online gaming motives, and problematic online game use, respectively. Structural regression analyses within structural equation modeling were used to test the proposed mediation models and multigroup analyses were used to test gender and game type differences to determine possible moderating effects. The mediation models fitted the data adequately. The Global Severity Index (GSI) of the BSI indicated that the level of psychiatric distress had a significant positive direct effect (standardized effect=.35, Pgaming motives: escape (standardized effect=.139, Pgaming (standardized effect size=.64

  3. Symposium of the International Society of Dynamic Games

    CERN Document Server

    Haurie, Alain; Annals of the International Society of Dynamic Games

    1994-01-01

    Recent years have witnessed a surge of activity in the field of dynamic both theory and applications. Theoretical as well as practical games, in problems in zero-sum and nonzero-sum games, continuous time differential and discrete time multistage games, and deterministic and stochastic games games are currently being investigated by researchers in diverse disciplines, such as engineering, mathematics, biology, economics, management science, and political science. This surge of interest has led to the formation of the International Society of Dynamic Games (ISDG) in 1990, whose primary goal is to foster the development of advanced research and applications in the field of game theory. One important activity of the Society is to organize biannually an international symposium which aims at bringing together all those who contribute to the development of this active field of applied science. In 1992 the symposium was organized in Grimentz, Switzerland, under the supervision of an international scientific committe...

  4. Gaming under the influence: An exploratory study.

    Science.gov (United States)

    Škařupová, Kateřina; Blinka, Lukas; Ťápal, Adam

    2018-05-23

    Background and aims Association between substance use and excessive play of online games exists both in theory and research. However, no study to date examined playing online games under the influence of licit and illicit drugs. Methods We questioned a convenient online sample of 3,952 Czech online gamers on their experiences and motives of using caffeine, alcohol, tobacco, psychoactive pharmaceuticals, and illicit drugs while playing massive multiplayer online games (MMOGs). Results The results showed low prevalence of illicit drug use while playing online games. Substance use was positively associated with intensity of gaming and both addiction and engagement; psychoactive substances with stimulating effect were linked to higher engagement and gaming intensity, whereas use of sedatives was associated with higher addiction score. Substance use varied slightly with the preference of game genre. Discussion Drug use while playing appears as behavior, which is mostly not related to gaming - it concerns mostly caffeine, tobacco, alcohol, or cannabis. For some users, however, drug use was fueled by motivations toward improving their cognitive enhancement and gaming performance.

  5. Proliferation and chondrogenic differentiation of CD105-positive enriched rat synovium-derived mesenchymal stem cells in three-dimensional porous scaffolds

    Energy Technology Data Exchange (ETDEWEB)

    Qi Jun; Chen Anmin; You Hongbo; Li Kunpeng; Zhang Di; Guo Fengjing, E-mail: fjguo@tjh.tjmu.edu.cn [Department of Orthopedics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030 (China)

    2011-02-15

    Stem cell-based tissue engineering has provided an alternative strategy to treat cartilage lesions, and synovium-derived mesenchymal stem cells (SMSCs) are considered as a promising cell source for cartilage repair. In this study, the SMSCs were isolated from rat synovium, and CD105-positive (CD105{sup +}) cells were enriched using magnetic activated cell sorting. Sorted cells were subsequently seeded onto the chitosan-alginate composite three-dimensional (3D) porous scaffolds and cultured in chondrogenic culture medium in the presence of TGF-{beta}{sub 3} and BMP-2 for 2 weeks in vitro. After 2 weeks in culture, scanning electron microscopy results showed that cells attached and proliferated well on scaffolds, and secreted extracellular matrix were also observed. From day 7 to day 14, the total DNA and glucosaminoglycan content of the cells cultured in scaffolds were found to have increased significantly, and cell cycle analyses revealed that the percentage of cells in the S and G2/M phases increased and the percentage of cells in the G0/G1 phase decreased. Compared with non-sorted cells, the sorted cells cultured in scaffolds underwent more chondrogenic differentiation, as evidenced by higher expression of type II collagen and Sox9 at the protein and mRNA levels. The results suggest that CD105{sup +} enriched SMSCs may be a potential cell source for cartilage tissue engineering, and the chitosan-alginate composite 3D porous scaffold could provide a favorable microenvironment for supporting proliferation and chondrogenic differentiation of cells.

  6. The standard set game of a cooperative game

    NARCIS (Netherlands)

    Bumb, A.F.; Hoede, C.

    2003-01-01

    We show that for every cooperative game a corresponding set game can be defined, called the standard set game. Values for set games can be applied to this standard game and determine allocations for the cooperative game. On the other hand, notions for cooperative games, like the Shapley value, the

  7. Positive Pedagogy for Sport Coaching

    Science.gov (United States)

    Light, Richard L.; Harvey, Stephen

    2017-01-01

    The literature suggests that, despite some challenges in their implementation, player/athlete-centred, inquiry-based approaches to teaching games and coaching team sport can improve game playing ability, increase player/athlete motivation and provide positive affective experiences of learning. A range of these approaches, including Teaching Games…

  8. Violent video games: The effects of narrative context and reward structure on in-game and postgame aggression.

    Science.gov (United States)

    Sauer, James D; Drummond, Aaron; Nova, Natalie

    2015-09-01

    The potential influence of video game violence on real-world aggression has generated considerable public and scientific interest. Some previous research suggests that playing violent video games can increase postgame aggression. The generalized aggression model (GAM) attributes this to the generalized activation of aggressive schemata. However, it is unclear whether game mechanics that contextualize and encourage or inhibit in-game violence moderate this relationship. Thus, we examined the effects of reward structures and narrative context in a violent video game on in-game and postgame aggression. Contrary to GAM-based predictions, our manipulations differentially affected in-game and postgame aggression. Reward structures selectively affected in-game aggression, whereas narrative context selectively affected postgame aggression. Players who enacted in-game violence through a heroic character exhibited less postgame aggression than players who enacted comparable levels of in-game violence through an antiheroic character. Effects were not attributable to self-activation or character-identification mechanisms, but were consistent with social-cognitive context effects on the interpretation of behavior. These results contradict the GAM's assertion that violent video games affect aggression through a generalized activation mechanism. From an applied perspective, consumer choices may be aided by considering not just game content, but the context in which content is portrayed. (c) 2015 APA, all rights reserved).

  9. Introduction of a new instrument to measure motivation for gaming: the electronic gaming motives questionnaire.

    Science.gov (United States)

    Myrseth, Helga; Notelaers, Guy; Strand, Leif Åge; Borud, Einar Kristian; Olsen, Olav Kjellevold

    2017-09-01

    To adapt the four-dimensional Gambling Motives Questionnaire-Revised (GMQ-R) to measure the motivation for engaging in electronic gaming, and to validate the internal structure and investigate the criterion validity of the new Electronic Gaming Motives Questionnaire (EGMQ). The GMQ-R was adapted to measure motivation for playing video games and the new instrument was tested on a sample of Norwegian conscripts selected randomly from the pool of conscripts who started their military service between 2013 and 2015. The questionnaire was administered to all those who had played video games during the last 6 months and consisted of 853 gamers (86.8% men, mean age = 19.4 years). All participants completed the EGMQ, as well as other measures of gaming behaviour, gaming problems, boredom, loneliness and depression. The confirmatory factor analyses showed that the proposed EGMQ (measuring enhancement, coping, social and self-gratification motives) displayed satisfactory fit and internal consistency. Hierarchical regression analyses showed that gender emerged as a significant predictor (P motivational dimensions explained an additional 5.8-38.8% of the variance. Coping and self-gratification predicted gaming problems (P motivational dimensions were also predicted differentially by indicators of psychosocial wellbeing, indicating divergent validity of the four motives. The four-dimensional Electronic Gaming Motives Questionnaire is a valid instrument for measuring motives for gaming. © 2017 Society for the Study of Addiction.

  10. Play, game, sport – and democratic self-determination

    DEFF Research Database (Denmark)

    Eichberg, Henning

    2015-01-01

    degree contradictory? Several languages use “play” and “game” in a differentiated way: Animals play, but do not engage in games – and the Olympic Games are not Olympic Play. Beneath this dualism, the relation becomes more complex and less dualistic, as Danish, Basque, and Korean languages show. We have......Sport as a sort of game receives its almost religious, sacral undertones from its kinship with play. This is what we learn from educational idealism as well as from Olympic ideology. At a closer glimpse, the phenomena of play, game, and sport are, however, much more differentiated – and to some...... to listen to the deeper knowledge of languages. Maybe, etymology and the anonymous folk speaking through language can tell us something important. Something which is more substantial than the sacral and normative constructions of sport idealism. The differentiation between play, game, and sport has...

  11. Verified Gaming

    DEFF Research Database (Denmark)

    Kiniry, Joseph Roland; Zimmerman, Daniel

    2011-01-01

    ---falls every year and any mention of mathematics in the classroom seems to frighten students away. So the question is: How do we attract new students in computing to the area of dependable software systems? Over the past several years at three universities we have experimented with the use of computer games......In recent years, several Grand Challenges (GCs) of computing have been identified and expounded upon by various professional organizations in the U.S. and England. These GCs are typically very difficult problems that will take many hundreds, or perhaps thousands, of man-years to solve. Researchers...

  12. Computer games and prosocial behaviour.

    Science.gov (United States)

    Mengel, Friederike

    2014-01-01

    We relate different self-reported measures of computer use to individuals' propensity to cooperate in the Prisoner's dilemma. The average cooperation rate is positively related to the self-reported amount participants spend playing computer games. None of the other computer time use variables (including time spent on social media, browsing internet, working etc.) are significantly related to cooperation rates.

  13. Losses Disguised as Wins Affect Game Selection on Multiline Slots.

    Science.gov (United States)

    Graydon, Candice; Stange, Madison; Dixon, Mike J

    2018-05-05

    Multiline slots are exciting games that contain features which make them alluring. One such feature is a loss disguised as a win (LDW); wherein, players win less than they wager (e.g., bet 2 dollars, win back 50 cents), but this net loss is disguised by flashing graphics and winning sounds. Research to date concludes that LDWs are both rewarding and reinforcing. Here, we investigated whether LDWs affect players' game selection. Thirty-two undergraduate students with experience playing slot machines played 100 spins on four games-two had positive payback percentages (115%) and two had negative payback percentages (85%) after 100 spins. For each payback percentage condition, there was a game with no LDWs and a game with a moderate number of LDWs. For the 100 spins, players could choose to play whichever game they wished. They then rated their preference for each game following the 100-spins and chose a game to continue playing. The majority of players preferred playing the positive payback percentage game with LDWs and chose to continue playing this game over the three other games. We conclude that in addition to LDWs being reinforcing and rewarding, LDWs do in fact influence game selection. We conclude that responsible gambling initiatives should educate players about LDWs.

  14. Mobile Game for Learning Bacteriology

    Science.gov (United States)

    Sugimura, Ryo; Kawazu, Sotaro; Tamari, Hiroki; Watanabe, Kodai; Nishimura, Yohei; Oguma, Toshiki; Watanabe, Katsushiro; Kaneko, Kosuke; Okada, Yoshihiro; Yoshida, Motofumi; Takano, Shigeru; Inoue, Hitoshi

    2014-01-01

    This paper treats serious games. Recently, one of the game genres called serious game has become popular, which has other purposes besides enjoyments like education, training and so on. Especially, learning games of the serious games seem very attractive for the age of video games so that the authors developed a mobile game for learning…

  15. Game-Based Teaching

    DEFF Research Database (Denmark)

    Hanghøj, Thorkild

    2013-01-01

    This chapter outlines theoretical and empirical perspectives on how Game-Based Teaching can be integrated within the context of formal schooling. Initially, this is done by describing game scenarios as models for possible actions that need to be translated into curricular knowledge practices...... approaches to game-based teaching, which may or may not correspond with the pedagogical models of particular games....

  16. Games for Learning

    Science.gov (United States)

    Gee, James Paul

    2013-01-01

    Today there is a great deal of interest in and a lot of hype about using video games in schools. Video games are a new silver bullet. Games can create good learning because they teach in powerful ways. The theory behind game-based learning is not really new, but a traditional and well-tested approach to deep and effective learning, often…

  17. Nested Potential Games

    OpenAIRE

    Hiroshi Uno

    2007-01-01

    This paper proposes a new class of potential games, the nested potential games, which generalize the potential games defined in Monderer and Shapley (1996), as well as the pseudo-potential games defined in Dubey et al. (2006). We show that each maximizer of a nested potential is a Nash equilibrium.

  18. Patience of matrix games

    DEFF Research Database (Denmark)

    Hansen, Kristoffer Arnsfelt; Ibsen-Jensen, Rasmus; Podolskii, Vladimir V.

    2013-01-01

    For matrix games we study how small nonzero probability must be used in optimal strategies. We show that for image win–lose–draw games (i.e. image matrix games) nonzero probabilities smaller than image are never needed. We also construct an explicit image win–lose game such that the unique optimal...

  19. Learning with Calculator Games

    Science.gov (United States)

    Frahm, Bruce

    2013-01-01

    Educational games provide a fun introduction to new material and a review of mathematical algorithms. Specifically, games can be designed to assist students in developing mathematical skills as an incidental consequence of the game-playing process. The programs presented in this article are adaptations of board games or television shows that…

  20. Play the Mosquito Game

    Science.gov (United States)

    ... and Work Teachers' Questionnaire Malaria Play the Mosquito Game Play the Parasite Game About the games Malaria is one of the world's most common ... last will in Paris. Play the Blood Typing Game Try to save some patients and learn about ...

  1. “HOW DO YOU FEEL?”: EMOTIONS EXHIBITED WHILE PLAYING COMPUTER GAMES AND THEIR RELATIONSHIP TO GAMING BEHAVIORS

    Directory of Open Access Journals (Sweden)

    Rex P. Bringula

    2015-06-01

    Full Text Available This descriptive study utilized a validated questionnaire to determine the emotions exhibited by computer gamers in cyber cafés. We determined that gamers exhibited both positive and negative emotions while playing games. We observed that gamers were inclined to be more anxious about being defeated in a game as gaming became frequent and length of years spent playing games increased. They also had the tendency to become more stressed when length of years spent playing games increased. On the other hand, other gaming behaviors were not significantly related to other emotions. We concluded that not all emotions exhibited by gamers while playing computer games could be attributed to their gaming behaviors. We recommend that other emotions such as anger, frustration, boredom, amusement, etc. be included in future research.

  2. Game Immersion Experience: Its Hierarchical Structure and Impact on Game-Based Science Learning

    Science.gov (United States)

    Cheng, M.-T.; She, H.-C.; Annetta, L. A.

    2015-01-01

    Many studies have shown the positive impact of serious educational games (SEGs) on learning outcomes. However, there still exists insufficient research that delves into the impact of immersive experience in the process of gaming on SEG-based science learning. The dual purpose of this study was to further explore this impact. One purpose was to…

  3. Gaming History: A Framework for What Video Games Teach about the Past

    Science.gov (United States)

    Metzger, Scott Alan; Paxton, Richard J.

    2016-01-01

    This article offers a typological framework for analyzing how video games make use of historical elements, shaping the ways players engage with and think about the past. Phenomenologically induced labels are posited for identifying different deployments of and experiences with historical elements in video games, illustrated by examples drawn from…

  4. Marketing in Game Design

    OpenAIRE

    Nurminen, Emilia

    2013-01-01

    In my thesis, Marketing in Game Design, I wanted to inspect how developing a game from a purely commercial perspective affects on the game design. The purpose of this thesis is to define the valid aspects of product marketing for games, how they are perceived in game industry and how those aspects affect to the game design. The question I am asking is how to make marketing a fluent part of indie game development process. Through my thesis project, Puzzleplatform, I study how the marketing asp...

  5. Computer Games and Art

    Directory of Open Access Journals (Sweden)

    Anton Sukhov

    2015-10-01

    Full Text Available This article devoted to the search of relevant sources (primary and secondary and characteristics of computer games that allow to include them in the field of art (such as the creation of artistic games, computer graphics, active interaction with other forms of art, signs of spiritual aesthetic act, own temporality of computer games, “aesthetic illusion”, interactivity. In general, modern computer games can be attributed to commercial art and popular culture (blockbuster games and to elite forms of contemporary media art (author’s games, visionary games.

  6. Game Theory of Pollution: National Policies and Their International Effects

    NARCIS (Netherlands)

    Schüller, Katharina; Stankova, Katerina; Thuijsman, Frank

    2017-01-01

    In this paper we put forward a simple game-theoretical model of pollution control, where each country is in control of its own pollution, while the environmental effects of policies do not stop at country borders. In our noncooperative differential game, countries as players minimize the present

  7. Experiential Learning about the Elderly: The Geriatric Medication Game.

    Science.gov (United States)

    Oliver, Carol H.; And Others

    1995-01-01

    An active learning simulation game designed to increase pharmacy students' awareness of the physical, psychological, and financial difficulties of the ambulatory elderly in handling their medication is described. Questionnaires before and after the game, including a semantic differential tool, indicate that the program is successful in increasing…

  8. Brain fMRI study of crave induced by cue pictures in online game addicts (male adolescents).

    Science.gov (United States)

    Sun, Yueji; Ying, Huang; Seetohul, Ravi M; Xuemei, Wang; Ya, Zheng; Qian, Li; Guoqing, Xu; Ye, Sun

    2012-08-01

    To study crave-related cerebral regions induced by game figure cues in online game addicts. fMRI brain imaging was done when the subjects were shown picture cues of the WoW (World of Warcraft, Version: 4.1.014250) game. 10 male addicts of WoW were selected as addicts' group, and 10 other healthy male non-addicts who were matched by age, were used as non-game addicts' group. All volunteers participated in fMRI paradigms. WoW associated cue pictures and neutral pictures were shown. We examined functional cerebral regions activated by the pictures with 3.0 T Philips MRI. The imaging signals' database was analyzed by SPM5. The correlation between game craving scores and different image results were assessed. When the game addicts watch the pictures, some brain areas show increased signal activity namely: dorsolateral prefrontal cortex, bilateral temporal cortex, cerebellum, right inferior parietal lobule, right cuneus, right hippocampus, parahippocampal gyrus, left caudate nucleus. But in these same brain regions we did not observe remarkable activities in the control group. Differential image signal densities of the addict group were subtracted from the health control group, results of which were expressed in the bilateral dorsolateral prefrontal cortex, anterior cingulate cortex, inferior parietal lobe and inferior temporal gyrus, cerebellum, right insular and the right angular gyrus. The increased imaging signal densities were significant and positively correlated with the craving scale scores in the bilateral prefrontal cortex, anterior cingulate cortex and right inferior parietal lobe. Craving of online game addicts was successfully induced by game cue pictures. Crave related brain areas are: dorsolateral prefrontal cortex, anterior cingulate cortex, and right inferior parietal lobe. The brain regions are overlapped with cognitive and emotion related processing brain areas. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Differential selection on carotenoid biosynthesis genes as a function of gene position in the metabolic pathway: a study on the carrot and dicots.

    Directory of Open Access Journals (Sweden)

    Jérémy Clotault

    Full Text Available Selection of genes involved in metabolic pathways could target them differently depending on the position of genes in the pathway and on their role in controlling metabolic fluxes. This hypothesis was tested in the carotenoid biosynthesis pathway using population genetics and phylogenetics.Evolutionary rates of seven genes distributed along the carotenoid biosynthesis pathway, IPI, PDS, CRTISO, LCYB, LCYE, CHXE and ZEP, were compared in seven dicot taxa. A survey of deviations from neutrality expectations at these genes was also undertaken in cultivated carrot (Daucus carota subsp. sativus, a species that has been intensely bred for carotenoid pattern diversification in its root during its cultivation history. Parts of sequences of these genes were obtained from 46 individuals representing a wide diversity of cultivated carrots. Downstream genes exhibited higher deviations from neutral expectations than upstream genes. Comparisons of synonymous and nonsynonymous substitution rates between genes among dicots revealed greater constraints on upstream genes than on downstream genes. An excess of intermediate frequency polymorphisms, high nucleotide diversity and/or high differentiation of CRTISO, LCYB1 and LCYE in cultivated carrot suggest that balancing selection may have targeted genes acting centrally in the pathway.Our results are consistent with relaxed constraints on downstream genes and selection targeting the central enzymes of the carotenoid biosynthesis pathway during carrot breeding history.

  10. The Uses of Teaching Games in Game Theory Classes and Some Experimental Games.

    Science.gov (United States)

    Shubik, Martin

    2002-01-01

    Discusses the use of lightly controlled games, primarily in classes in game theory. Considers the value of such games from the viewpoint of both teaching and experimentation and discusses context; control; pros and cons of games in teaching; experimental games; and games in class, including cooperative game theory. (Author/LRW)

  11. Deterministic Graphical Games Revisited

    DEFF Research Database (Denmark)

    Andersson, Daniel; Hansen, Kristoffer Arnsfelt; Miltersen, Peter Bro

    2008-01-01

    We revisit the deterministic graphical games of Washburn. A deterministic graphical game can be described as a simple stochastic game (a notion due to Anne Condon), except that we allow arbitrary real payoffs but disallow moves of chance. We study the complexity of solving deterministic graphical...... games and obtain an almost-linear time comparison-based algorithm for computing an equilibrium of such a game. The existence of a linear time comparison-based algorithm remains an open problem....

  12. Chemical evolutionary games.

    Science.gov (United States)

    Aristotelous, Andreas C; Durrett, Richard

    2014-05-01

    Inspired by the use of hybrid cellular automata in modeling cancer, we introduce a generalization of evolutionary games in which cells produce and absorb chemicals, and the chemical concentrations dictate the death rates of cells and their fitnesses. Our long term aim is to understand how the details of the interactions in a system with n species and m chemicals translate into the qualitative behavior of the system. Here, we study two simple 2×2 games with two chemicals and revisit the two and three species versions of the one chemical colicin system studied earlier by Durrett and Levin (1997). We find that in the 2×2 examples, the behavior of our new spatial model can be predicted from that of the mean field differential equation using ideas of Durrett and Levin (1994). However, in the three species colicin model, the system with diffusion does not have the coexistence which occurs in the lattices model in which sites interact with only their nearest neighbors. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Recall and Recognition of In-Game Advertising: The Impact of Game Control

    Directory of Open Access Journals (Sweden)

    Laura eHerrewijn

    2014-01-01

    Full Text Available Digital gaming has become one of the largest entertainment sectors worldwide, increasingly turning the medium into a promising vehicle for advertisers. As a result, the inclusion of advertising messages in digital games or in-game advertising (IGA is expected to grow steadily over the course of the following years. However, much work is still needed to maximize the effectiveness of IGA. The aim of the study was to contribute to IGA effectiveness research by analyzing the impact of two factors on the processing of IGA in terms of brand awareness. The primary objective was to investigate the effect of a person’s sense of involvement related to the control and movement mechanisms in a game (i.e. kinesthetic involvement. A within-subjects experiment was conducted in which control over a racing game was varied by manipulating game controller type, resulting in two experimental conditions (symbolic versus mimetic controller. Results show that the variation in game controller has a significant effect on the recall and recognition of the brands integrated into the game, and that this effect can be partially brought back to players’ perceived control over the game: when a game is easier to control, the control mechanisms require less conscious attention, freeing attentional resources that can be subsequently spent on other elements of the game such as IGA. A second factor that was taken into account in the study was brand prominence. The influence of both the size and spatial position of in-game advertisements was examined. Findings demonstrate that there are significant changes in effectiveness between different types of placements. Spatial position seems to be the most important placement characteristic, with central brand placements obtaining the highest recall and recognition scores. The effect of ad size is much smaller, with the effectiveness of the large placements not differing significantly from the effectiveness of their smaller

  14. Recall and recognition of in-game advertising: the role of game control.

    Science.gov (United States)

    Herrewijn, Laura; Poels, Karolien

    2013-01-01

    Digital gaming has become one of the largest entertainment sectors worldwide, increasingly turning the medium into a promising vehicle for advertisers. As a result, the inclusion of advertising messages in digital games or in-game advertising (IGA) is expected to grow steadily over the course of the following years. However, much work is still needed to maximize the effectiveness of IGA. The aim of the study was to contribute to IGA effectiveness research by analyzing the impact of two factors on the processing of IGA in terms of brand awareness. The primary objective was to investigate the effect of a person's sense of involvement related to the control and movement mechanisms in a game (i.e., kinesthetic involvement). A within-subjects experiment was conducted in which control over a racing game was varied by manipulating game controller type, resulting in two experimental conditions (symbolic versus mimetic controller). Results show that the variation in game controller has a significant effect on the recall and recognition of the brands integrated into the game, and that this effect can be partially brought back to players' perceived control over the game: when a game is easier to control, the control mechanisms require less conscious attention, freeing attentional resources that can be subsequently spent on other elements of the game such as IGA. A second factor that was taken into account in the study was brand prominence. The influence of both the size and spatial position of in-game advertisements was examined. Findings demonstrate that there are significant changes in effectiveness between different types of placements. Spatial position seems to be the most important placement characteristic, with central brand placements obtaining the highest recall and recognition scores. The effect of ad size is much smaller, with the effectiveness of the large placements not differing significantly from the effectiveness of their smaller counterparts.

  15. European Conference on Game Theory & Networking Games and Management

    CERN Document Server

    Mazalov, Vladimir

    2016-01-01

    This contributed volume contains fourteen papers based on selected presentations from the European Conference on Game Theory SING11-GTM 2015, held at Saint Petersburg State University in July 2015, and the Networking Games and Management workshop, held at the Karelian Research Centre of the Russian Academy of Sciences in Petrozvavodsk, Russia, also in July 2015. These papers cover a wide range of topics in game theory, including recent advances in areas with high potential for future work, as well as new developments on classical results. Some of these include A new approach to journal ranking using methods from social choice theory; A differential game of a duopoly in which two firms are competing for market share in an industry with network externalities; The impact of information propagation in the model of tax audits; A voting model in which the results of previous votes can affect the process of coalition formation in a decision-making body; The Selten-Szidarovsky technique for the analysis of Nash equil...

  16. Games on Games. Game Design as Critical Reflexive Practice

    OpenAIRE

    Giovanni Caruso; Riccardo Fassone; Gabriele Ferri; Stefano Gualeni; Mauro Salvador

    2016-01-01

    Can video game design be compared to more formalized practices of scientific research or speculation within game studies? And, by virtue of an intellectual leap that in itself calls for discussion, can video games be considered as an efficient vehicle for the presentation of certain kinds of knowledge, in the same way in which papers, conference presentations, and books are? What Ratto defines as critical making (2011), the practice of producing artifacts of different sorts in order to supple...

  17. The expected-outcome model of two-player games

    CERN Document Server

    Abramson, Bruce

    1990-01-01

    The Expected-Outcome Model of Two-Player Games deals with the expected-outcome model of two-player games, in which the relative merit of game-tree nodes, rather than board positions, is considered. The ambiguity of static evaluation and the problems it generates in the search system are examined and the development of a domain-independent static evaluator is described. Comprised of eight chapters, this book begins with an overview of the rationale for the mathematical study of games, followed by a discussion on some previous artificial intelligence (AI) research efforts on game-trees. The nex

  18. Playing prosocial video games increases the accessibility of prosocial thoughts.

    Science.gov (United States)

    Greitemeyer, Tobias; Osswald, Silvia

    2011-01-01

    Past research has provided abundant evidence that playing violent video games increases aggressive tendencies. In contrast, evidence on possible positive effects of video game exposure on prosocial tendencies has been relatively sparse. The present research tested and found support for the hypothesis that exposure to prosocial video games increases the accessibility of prosocial thoughts. These results provide support to the predictive validity of the General Learning Model (Buckley & Anderson, 2006) for the effects of exposure to prosocial media on social tendencies. Thus, depending on the content of the video game, playing video games can harm but may also benefit social relations.

  19. Video game addiction in children and teenagers in Taiwan.

    Science.gov (United States)

    Chiu, Shao-I; Lee, Jie-Zhi; Huang, Der-Hsiang

    2004-10-01

    Video game addiction in children and teenagers in Taiwan is associated with levels of animosity, social skills, and academic achievement. This study suggests that video game addiction can be statistically predicted on measures of hostility, and a group with high video game addiction has more hostility than others. Both gender and video game addiction are negatively associated with academic achievement. Family function, sensation seeking, gender, and boredom have statistically positive relationships with levels of social skills. Current models of video game addiction do not seem to fit the findings of this study.

  20. Personality traits and life satisfaction among online game players.

    Science.gov (United States)

    Chen, Lily Shui-Lien; Tu, Hill Hung-Jen; Wang, Edward Shih-Tse

    2008-04-01

    The DFC Intelligence predicts worldwide online game revenues will reach $9.8 billion by 2009, making online gaming a mainstream recreational activity. Understanding online game player personality traits is therefore important. This study researches the relationship between personality traits and life satisfaction in online game players. Taipei, Taiwan, is the study location, with questionnaire surveys conducted in cyber cafe shops. Multiple regression analysis studies the causal relationship between personality traits and life satisfaction in online game players. The result shows that neuroticism has significant negative influence on life satisfaction. Both openness and conscientiousness have significant positive influence on life satisfaction. Finally, implications for leisure practice and further research are discussed.