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51.
The new industry of Massively Multi-Player Online Role-Playing Games (MMORPGs) brings together two sets of fictions: the interactive stories of shared computer games and the legal devices of intellectual property. In these virtual worlds, scarcity need not exist, but players tend to prefer the competition it creates. This leads to the development of property rights within the game world and players trading real money for virtual objects, ‘land’ and characters. This new phenomenon brings with it familiar legal problems such as theft, fraud and ownership disputes. Game creators also challenge the right of the players to claim ownership outside the game world. The volume and value of the items traded make real money trading an important area of current interest for intellectual property lawyers. Something is being traded, but does it fit neatly into existing conceptions of property rights and who owns it? Analysing the novel problems that result from various theoretical perspectives (utilitarianism, labour-desert theory and personality theory) leads to the conclusion that with time, we will see the development of property rights for players in online games. This connects with a growing understanding that the traditional conception of copyright law dealing with creative work generated by the solitary author is becoming less appropriate in the new creative spaces that information and communications technology brings, where individuals are both consumer and producer. In virtual worlds, new forms of intellectual property, and perhaps even new rights, are taking shape.  相似文献   
52.
Formal translations constitute a suitable framework for dealing with many problems in pattern recognition and computational linguistics. The application of formal transducers to these areas requires a stochastic extension for dealing with noisy, distorted patterns with high variability. In this paper, some estimation criteria are proposed and developed for the parameter estimation of regular syntax-directed translation schemata. These criteria are: maximum likelihood estimation, minimum conditional entropy estimation and conditional maximum likelihood estimation. The last two criteria were proposed in order to deal with situations when training data is sparse. These criteria take into account the possibility of ambiguity in the translations: i.e., there can be different output strings for a single input string. In this case, the final goal of the stochastic framework is to find the highest probability translation of a given input string. These criteria were tested on a translation task which has a high degree of ambiguity.  相似文献   
53.
The increased availability of large scale computational facilities is enabling the use of computational modelling for the treatment of complex problems of industrial interest. Computational haemodynamics is an area where improved computational power and algorithmic development have permitted the application in biomechanics of techniques originally devised for direct numerical simulations in others areas of scientific interest. In this paper we present a highly accurate algorithm for the numerical solution of the incompressible Navier–Stokes equations which employs a spectral/hp element spatial discretisation and a high-order time splitting. Two important developments discussed in this paper are the coupling of these techniques with unstructured mesh generation, used in many everyday engineering applications, and the introduction of a non-Newtonian viscosity model to account for the shear thinning properties of blood. The proposed method will be applied to the analysis of shear stress distributions in flows of interest in haemodynamics. Received: 5 May 1999 / Accepted: 21 september 1999  相似文献   
54.
De Candolle analyzed in 1883 and 1885, respectively two important fields of human cultural evolution: the domestication of crop plants and the emergence of modern science. In hisHistoire de science et des savants depuis deux sciecles, principles were established, science indicators outlined, interactions examined and mathematical methods applied to the study of a selected data set related to scientific development. In order to compare national and international scientific communities twenty standard factors were considered and national participation in international scientific societies was analysed for 14 European countries and the United States.De Candolle was the first to analyse mathematically the number, dynamics and national distribution of scientists in their professional organisations, the specialization and professionalization of scientists and characterized the scientific potential of different countries with the number of international science society members per inhabitant per period (1750–1884). The role ofde Candolle as a forerunner of modern scientometrics and the science of science is revealed in a comparison of his work with recent trends. In the first five volumes of the journalScientometrics 51 papers were identified dealing with topics related to those dealt with byde Candolle.  相似文献   
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Free-Form Deformation Techniques (FFD) are commonly used to generate animations, where a polygonal approximation of the final object suffices for visualization purposes. However, for some CAD/CAM applications, we need an explicit expression of the object, rather than a collection of sampled points. If both object and deformation are polynomial, their composition yields a result that is also polynomial, albeit very high degree, something undesirable in real applications. To solve this problem, we transform each curve or surface composing the object, usually expressed in the Bernstein basis, to a modified Newton form. In this representation, the two-point analogue of Taylor expansions, the composition admits a simple expression in terms of discrete convolutions, and degree reduction corresponding to Hermite approximation is trivial by dropping high-degree coefficients. Furthermore, degree-reduction can be incorporated into the composition. Finally, the deformed curve or surface is converted back to the Bernstein form. This method extends to general non-polynomial deformation, such as bending and twisting, by computing a polynomial approximant of the deformation.  相似文献   
58.
We present a model based on determinist cellular automata architecture for studying systems with frustrated interactions that present elemental excitations, such as magnetic monopoles. This model is especially designed to be applied for systems with components that have energy levels much higher than kT. This would imply that for these systems thermal fluctuations are negligible and they can be analyzed under the supposition that the dynamic is produced at zero temperature. This category includes artificial magnetic spin ice systems and donor and recipient electrical charge molecular systems. The dynamics of these systems can be simulated in real time with this model, with a minimum of computational requirements. It can be an excellent complement to Monte Carlo methods and in some cases can even replace them directly. In this report, we show the designed structure and some interesting results obtained in studying the dynamics of emergent magnetic monopoles in artificial spin ice systems and excitations in graphane molecular arrays.  相似文献   
59.
Researches on Ambient Intelligent and Ubiquitous Computing using wireless technologies have increased in the last years. In this work, we review several scenarios to define a multi-agent architecture that support the information needs of these new technologies, for heterogeneous domain. Our contribution consists of designing in a methodological way a Context Aware System (involving location services) using agents that can be used in very different domains. We describe all the steps followed in the design of the agent system. We apply a hybridizing methodology between GAIA and AUML. Additionally we propose a way to compare different agent architectures for Context Aware System using agent interactions. So, in this paper, we describe the assignment of weight values to agents interaction in two different MAS architectures for Context Aware problems solving different scenarios inspired in FIPA standard negotiation protocols.  相似文献   
60.
This study examined the mediating role of service climate in the prediction of employee performance and customer loyalty. Contact employees (N=342) from 114 service units (58 hotel front desks and 56 restaurants) provided information about organizational resources, engagement, and service climate. Furthermore, customers (N=1,140) from these units provided information on employee performance and customer loyalty. Structural equation modeling analyses were consistent with a full mediation model in which organizational resources and work engagement predict service climate, which in turn predicts employee performance and then customer loyalty. Further analyses revealed a potential reciprocal effect between service climate and customer loyalty. Implications of the study are discussed, together with limitations and suggestions for future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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