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81.
The present study investigates the impact of the experience of role playing a violent character in a video game on attitudes towards violent crimes and criminals. People who played the violent game were found to be more acceptable of crimes and criminals compared to people who did not play the violent game. More importantly, interaction effects were found such that people were more acceptable of crimes and criminals outside the game if the criminals were matched with the role they played in the game and the criminal actions were similar to the activities they perpetrated during the game. The results indicate that people’s virtual experience through role-playing games can influence their attitudes and judgments of similar real-life crimes, especially if the crimes are similar to what they conducted while playing games. Theoretical and practical implications are discussed. 相似文献
82.
The Boyer and Moore (BM) pattern matching algorithm is considered as one of the best, but its performance is reduced on binary data. Yet, searching in binary texts has important applications, such as compressed matching. The paper shows how, by means of some pre-computed tables, one may implement the BM algorithm also for the binary case without referring to bits, and processing only entire blocks such as bytes or words, thereby significantly reducing the number of comparisons. Empirical comparisons show that the new variant performs better than regular binary BM and even than BDM. 相似文献
83.
84.
Stefan Klein Josien P. W. Pluim Marius Staring Max A. Viergever 《International Journal of Computer Vision》2009,81(3):227-239
We present a stochastic gradient descent optimisation method for image registration with adaptive step size prediction. The
method is based on the theoretical work by Plakhov and Cruz (J. Math. Sci. 120(1):964–973, 2004). Our main methodological contribution is the derivation of an image-driven mechanism to select proper values for the most
important free parameters of the method. The selection mechanism employs general characteristics of the cost functions that
commonly occur in intensity-based image registration. Also, the theoretical convergence conditions of the optimisation method
are taken into account. The proposed adaptive stochastic gradient descent (ASGD) method is compared to a standard, non-adaptive
Robbins-Monro (RM) algorithm. Both ASGD and RM employ a stochastic subsampling technique to accelerate the optimisation process.
Registration experiments were performed on 3D CT and MR data of the head, lungs, and prostate, using various similarity measures
and transformation models. The results indicate that ASGD is robust to these variations in the registration framework and
is less sensitive to the settings of the user-defined parameters than RM. The main disadvantage of RM is the need for a predetermined
step size function. The ASGD method provides a solution for that issue. 相似文献
85.
Realistic terrain models are required in many applications, especially in computer games. Commonly, procedural models are applied to generate the corresponding models and let users experience a wide variety of new environments. Existing algorithms generate landscapes immediately with view‐dependent resolution and without preprocessing. Unfortunately, landscapes generated by such algorithms lack river networks and therefore appear unnatural. Algorithms that integrate realistic river networks are computationally expensive and cannot be used to generate a locally adaptive high resolution landscape during a fly‐through. In this paper, we propose a novel algorithm to generate realistic river networks. Our procedural algorithm creates complete planets and landscapes with realistic river networks within seconds. It starts with a coarse base geometry of a planet without further preprocessing and user intervention. By exploiting current graphics hardware, the proposed algorithm is able to generate adaptively refined landscape geometry during fly‐throughs. 相似文献
86.
Degener P Schnabel R Schwartz C Klein R 《IEEE transactions on visualization and computer graphics》2008,14(6):1452-1458
In this work we develop a new alternative to conventional maps for visualization of relatively short paths as they are frequently encountered in hotels, resorts or museums. Our approach is based on a warped rendering of a 3D model of the environment such that the visualized path appears to be straight even though it may contain several junctions. This has the advantage that the beholder of the image gains a realistic impression of the surroundings along the way which makes it easy to retrace the route in practice. We give an intuitive method for generation of such images and present results from user studies undertaken to evaluate the benefit of the warped images for orientation in unknown environments. 相似文献
87.
Abstract In this study Virtual Reality technology was used to simulate a toddler's first few days' experiences in daycare and improve the caregiver's understanding of their state of mind. The virtual worlds were developed in accordance with toddlers' way of thinking and from their cognitive and visual viewpoint. The aim of the research was to investigate whether the caregiver's awareness to the cognitive experiences that toddlers undergo in their first days in kindergarten improves through a VR simulation of toddlers' worlds. Six cognitive elements of toddlers were simulated: object constancy; trial and error; perspective of height; perspective of things; egocentricity and imagination. The participants in this study were 40 (female) caregivers who work with infants aged 6 months to 4 years in private daycare. The findings indicate that experiencing a virtual world that reflects the real world of children improves the caregiver's awareness to the cognitive experiences that toddlers undergo in their first days in a kindergarten or daycare. 相似文献
88.
This paper describes a novel knowledge-based methodology and toolset for helping business process designers and participants
better manage exceptions (unexpected deviations from an ideal sequence of events caused by design errors, resource failures,
requirement changes, etc.) that can occur during the enactment of a process. This approach is based on an on-line repository
exploiting a generic and reusable body of knowledge, which describes what kinds of exceptions can occur in collaborative work
processes, how these exceptions can be detected, and how they can be resolved. This work builds upon previous efforts from
the MIT Process Handbook project and from research on conflict management in collaborative design.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
89.
B. W. Statt W. N. Hardy A. J. Berlinsky E. Klein 《Journal of Low Temperature Physics》1985,61(5-6):471-504
Spin-polarized atomic hydrogen (H) gas has been studied using electron spin resonance (ESR) techniques at low temperatures. The ESR apparatus and consequent data analysis required for accurate quantitative results are described in detail. Crucial to the data analysis is the ability to confine the sample of H gas inside a liquid helium-coated microwave cavity where the magnetic field and temperature are constant. Results obtained so far are reported, which include the first detailed study of the one-body surface relaxation rate due to microscopic magnetic impurities in the cell walls. 相似文献
90.
The nonlinear flux-flow behavior due to the nonequilibrium distribution of quasiparticles predicted by Larkin and Ovchinnikov has been observed in thin films of Al, In, and Sn. From the voltage-current characteristics the inelastic scattering time
E
of the electrons was obtained. For Al and In the values of
E
are in excellent agreement with the previous results. For Sn the value
E
=5×10–10 sec is slightly larger than the previous results. 相似文献