Managing Workflow Authorization Constraints through Active Database Technology

The execution of workflow processes requires authorizations for enforcing the assignment of tasks to agents, either human or automated, according to the security policy of the organization. This paper presents a workflow authorization framework based on roles and organizational levels, and on authorization constraints. To facilitate the assignment of tasks to agents, roles and organizational levels are organized into hierarchies. Authorization constraints are introduced to specify instance-dependent, time-dependent, and history-dependent authorizations. Authorization constraints are specified in terms of active rules, used also for authorization management. The Workflow Management System determines authorized agents on the basis of the contents of an authorization base maintained through the active rules defined in the system.     

基于VQ的说话人识别系统

该文介绍了一种基于矢量量化(VQ)方法的一个说话人识别算法。基于矢量量化的说话人识别,因其运算过程简单等特点,在说话人识别领域有着广泛的应用。用不同语音参数进行实验,实验表明应用矢量量化的方法用在说话人识别中是一种有效方法。     

Motion‐blur characterization on liquid‐crystal displays

Abstract— In this paper, several methods to characterize motion blur on liquid‐crystal displays are reviewed. Based on the assumptions of smooth‐pursuit eye tracking and one‐frame temporal luminance integration, a simple algorithm has been proposed to calculate the normalized blurred edge width (N‐BEW) and motion‐picture response time (MPRT) with a one‐frame‐time moving‐window function to LC temporal step response curves. A custom measurement system with a fast‐eye‐sensitivity‐compensated photodiode has been developed to characterize motion blur based on LC response curves (LCRCs). MPRT values obtained by using the algorithm mentioned above and those from the smooth‐pursuit‐camera methods agree. Perception experiments were conducted to validate the correspondence between the simulated results and actual perceived images by the human eyes. In addition, the insufficiency of MPRT to evaluate motion blur on impulse‐type light‐generation LCDs, by analyzing the measurement results of a scanning backlight LCD, is discussed.     

Power savings and enhancement of gray‐scale capability of LCD TVs with an adaptive dimming technique

Abstract— The luminance of a backlight unit for an LCD TV is adaptively and locally dimmed along with the input video signal in order to reduce the power consumption and also to improve the picture quality. By adopting the zero‐dimensional (0D), 1D, and 2D adaptive dimming techniques, a sample movie having 8.0% post‐gamma average picture levels (APL) could be displayed using 83%, 71%, and 50% of the original backlight power, respectively. For an adoption of the 2D dimming, an LED backlight is preferable. The adaptive‐dimming technique also allows the differential aging characteristics between the LED components and temperature dependence of color and luminance to be overcome. From simulations of a reduction in power consumption, it was found that 40 × 40 pixels is a unit of the local dimming, 30 frames for the sampling period, 24 dimming steps, and an equal‐signal‐step method for determining the dimming factor have been found to be appropriate. The gray‐scale capability of low‐luminance images can also be improved by dimming the backlight luminance and expanding the input signal. By using an LCD TV having an 8‐bit capability, an 11‐bit‐equivalent gray‐scale expression was experimentally proven.     

Characterizing displays by their temporal aperture: A theoretical framework

Abstract— The spatio‐temporal aperture and sample rate of a video display determines both the static and dynamic resolution of the video signal that is rendered. The dynamic display characteristics like the visibility of large‐area flicker, motion judder, and motion blur can be derived from the frame rate and the temporal extent of the pixel aperture (i.e., the temporal aperture). For example, liquid‐crystal displays (LCDs) have an aperture that is relatively small in the spatial dimension and wide in the temporal domain. Consequently, moving objects displayed on an LCD suffer from motion blur. Especially in TV applications, the temporal dimension has a large impact on the overall picture quality. The temporal aperture, together with the frame rate, is shown to predict the amount of perceived large‐area flicker, motion judder, and motion blur and also the performance of motion‐blur reduction algorithms for LCDs. From this analysis it is further determined how to obtain the optimal temporal aperture of a television display, for which not only properties of the human visual system (HVS), but also the properties of the video signal have to be taken into account.     

剪刀下的民间文化——民间剪纸的造型特点

民间剪纸是我国民间美术形式之一,有着悠久的历史。本文从剪纸的构图方法、剪纸的造型手段、剪纸的吉祥祝愿三个方面,分析剪纸的造型特点,从而体现出剪纸的造型源于原始的视觉思维方式和民间审美观念。     

“操作系统”课程教学实践环节思考

本文是教授"操作系统"课的心得体会。提出了对"操作系统"课程的一些思考以及对教材改革的思路,并且指出了传统的"操作系统"课程教学环节的弊端和实践环节在"操作系统"这门课中的重要性以及实践环节的多样性,最后指出要从培养高水平的创新性人才出发,研究教材改革的方向和思路。     

Technology roles and paths of influence in an ecosystem model of technology evolution

We propose a new conceptual model for understanding technology evolution that highlights dynamic and highly interdependent relationships among multiple technologies. We argue that, instead of considering technologies in isolation, technology evolution is best viewed as a dynamic system or ecosystem that includes a variety of interrelated technologies. By considering the interdependent nature of technology evolution, we identify three roles that technologies play within a technology ecosystem. These roles are components, products and applications, and support and infrastructure. Technologies within an ecosystem interact through these roles and impact each others’ evolution. We also classify types of interactions between technology roles, which we term paths of influence. We demonstrate the use of our proposed model through examples of wireless networking (Wi-Fi) technologies and a business mini-case on the digital music industry.

1993: Axline's eight principles of play therapy revisited.

Examined V. Axlines's book, Play Therapy (1947) which includes 8 basic principles on non-directive play therapy. Student responses to learning these principles in play therapy classes were also examined. Each student was assigned a play therapy client and was observed and assisted directly by the instructor, a licensed clinical psychologist. Clients were mildly trouble children (aged 5–10 yrs) and were selected from a referral base by the instructor as appropriate for the course. As the semester progressed and students gained direct experience, weekly small (3–4 student) group discussions were held to explore in-depth understanding of play therapy principles and how these principles are put into practice. It is concluded that Axline's book remains a classic text and a foremost resource in the field. Coupling it with experiential learning is an invaluable basis for teaching play therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Discrimination or favoritism? Sex bias in book reviews.

Studied 180 reviews of books written by male, female, or male and female authors to investigate sex bias. Half the books had been reviewed by males, half by females. Each review was rated separately for positive and negative elements. For positive elements, there was a significant interaction between author's and reviewer's sex: same-sex books were more favorably evaluated than other-sex books, while books of mixed authorship fell in between. There was no comparable interaction for negative elements. Reviewers of both sexes tended to find more negative elements in books by male than by female authors. It is concluded that unlike in studies employing hypothetical situations, in real-life settings each sex is biased in favor of itself. (PsycINFO Database Record (c) 2010 APA, all rights reserved)