Analysis of the Finite Element Method for the Laplace–Beltrami Equation on Surfaces with Regions of High Curvature Using Graded Meshes

We derive error estimates for the piecewise linear finite element approximation of the Laplace–Beltrami operator on a bounded, orientable, \(C^3\), surface without boundary on general shape regular meshes. As an application, we consider a problem where the domain is split into two regions: one which has relatively high curvature and one that has low curvature. Using a graded mesh we prove error estimates that do not depend on the curvature on the high curvature region. Numerical experiments are provided.     

The effect of action video game experience on task-switching

There is now a substantial body of work demonstrating that action video game experience results in enhancements in a wide variety of perceptual skills. More recently, several groups have also demonstrated improvements in abilities that are more cognitive in nature, in particular, the ability to efficiently switch between tasks. In a series of four experiments, we add to this body of work, demonstrating that the action video game player advantage is not exclusively due to an ability to map manual responses onto arbitrary buttons, but rather generalizes to vocal responses, is not restricted to tasks that are perceptual in nature (e.g. respond to a physical dimension of the stimulus such as its color), but generalizes to more cognitive tasks (e.g. is a number odd or even), and is present whether the switch requires a goal-switch or only a motor switch. Finally, a training study establishes that the relationship between the reduction in switch cost and action game playing is causal.     

The Variety of Variables in Computer-Aided Real-Time Programming

The refinement calculus is a well-established theory for translating specifications to program code. Recent research has extended the calculus to handle real-time requirements and we have developed an interactive support tool based on these extensions. Via a case study, this paper shows how the tool helps the programmer by supporting the many forms of variables used in the theory. These include simple state variables as in the untimed calculus, timed-trace variables that model the evolution of properties over time, and auxiliary variables that exist to support formal reasoning only.     

Multilevel Robustness for 2D Vector Field Feature Tracking,Selection and Comparison

Critical point tracking is a core topic in scientific visualization for understanding the dynamic behaviour of time-varying vector field data. The topological notion of robustness has been introduced recently to quantify the structural stability of critical points, that is, the robustness of a critical point is the minimum amount of perturbation to the vector field necessary to cancel it. A theoretical basis has been established previously that relates critical point tracking with the notion of robustness, in particular, critical points could be tracked based on their closeness in stability, measured by robustness, instead of just distance proximity within the domain. However, in practice, the computation of classic robustness may produce artifacts when a critical point is close to the boundary of the domain; thus, we do not have a complete picture of the vector field behaviour within its local neighbourhood. To alleviate these issues, we introduce a multilevel robustness framework for the study of 2D time-varying vector fields. We compute the robustness of critical points across varying neighbourhoods to capture the multiscale nature of the data and to mitigate the boundary effect suffered by the classic robustness computation. We demonstrate via experiments that such a new notion of robustness can be combined seamlessly with existing feature tracking algorithms to improve the visual interpretability of vector fields in terms of feature tracking, selection and comparison for large-scale scientific simulations. We observe, for the first time, that the minimum multilevel robustness is highly correlated with physical quantities used by domain scientists in studying a real-world tropical cyclone dataset. Such an observation helps to increase the physical interpretability of robustness.     

Psychometric properties of the Hawaiian Culture Scale—Adolescent Version.

This article reports on the psychometric properties of a newly constructed Hawaiian Culture Scale—Adolescent Version. A total of 2,272 Native Hawaiian and 1,170 non-Hawaiian adolescents were administered this 50-item inventory that measures the source of learning the Hawaiian way of life, how much Hawaiian beliefs are valued and important to maintain, how much non-Hawaiian beliefs are valued, Hawaiian blood quantum, and specific cultural traditions (seven subscales?=?Lifestyles, Customs, Activities, Folklore, Causes—Locations, Causes—Access, and Language Proficiency). The results strongly supported the internal consistency and validity of the measures for both the Hawaiian and non-Hawaiian groups. On the basis of the demographic data, partial support was offered for cross-cultural theories of ethnic identity. More consistent support was found for multiculturalism in Hawai'i's adolescents. Further research is needed to link these measures with indicators of psychological adjustment (e.g., depression, anxiety, substance use). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

TRAVOS: Trust and Reputation in the Context of Inaccurate Information Sources

In many dynamic open systems, agents have to interact with one another to achieve their goals. Here, agents may be self-interested, and when trusted to perform an action for another, may betray that trust by not performing the action as required. In addition, due to the size of such systems, agents will often interact with other agents with which they have little or no past experience. There is therefore a need to develop a model of trust and reputation that will ensure good interactions among software agents in large scale open systems. Against this background, we have developed TRAVOS (Trust and Reputation model for Agent-based Virtual OrganisationS) which models an agent’s trust in an interaction partner. Specifically, trust is calculated using probability theory taking account of past interactions between agents, and when there is a lack of personal experience between agents, the model draws upon reputation information gathered from third parties. In this latter case, we pay particular attention to handling the possibility that reputation information may be inaccurate.     

Reduction of defects and improvement in the performance of blue phosphor for thick‐dielectric electroluminescent displays using Color‐by‐Blue

Abstract— Defect‐free large‐area inorganic thick‐dielectric EL (TDEL) displays using Color by Blue (CBB) technology have been successfully developed. We have achieved the world's highest blue‐phosphor luminance of 900 cd/m² for a single‐pixel device by using CBB and by optimizing the e‐beam gun configuration and the flow rate of H₂S in the vacuum chamber. By analyzing the defects on panels with triple‐pattern phosphors and CBB panels, we also found that the number of defects on CBB panels can be drastically reduced compared with those on triple‐pattern panels. The defect‐free 17‐in. VGA CBB panels show better characteristics, a high peak luminance of 600 cd/m² and a high contrast ratio of 1000:1, compared with those of triple‐pattern panels.     

User-Level Device Drivers: Achieved Performance

Running device drivers as unprivileged user-level code, encapsulated into their own process, has often been proposed as a technique for increasing system robustness. However, in the past, systems based on user-level drivers have generally exhibited poor I/O performance. Consequently, user-level device drivers have never caught on to any significant degree. In this paper we demonstrate that it is possible to build systems which employ user-level device drivers, without significant performance degradation, even for high-bandwidth devices such as Gigabit Ethernet.     

An empirical investigation of the novice experience with soft keyboards

An experiment with 12 participants tested text entry rates on two sizes of soft keyboards with either a Qwerty layout or a layout presenting a randomized letter arrangement after each tap. The randomized layout simulated the novice experience by requiring users to visually scan the layout for each tap to find the intended letter. Rates for the Qwerty layouts were about 20 wpm with no significant difference between the large and small size. Rates for both sizes of the randomized layouts were very low, about 5.4 wpm. This is the expected walk-up text entry rate with a soft keyboard bearing an unfamiliar layout. This empirical result allows us to reject a previous model of novice interaction that used Fitts' law for stylus movement and the Hick-Hyman law for visual scan time.