Signal transformation and interpolation based on modified DCT synthesis

This paper proposes a novel signal transformation and interpolation approach based on the modification of DCT (Discrete Cosine Transform). The proposed algorithm can be applied to any periodic or quasi periodic waveform for time scale and/or pitch modification purposes in addition to signal reconstruction, compression, coding and packet lost concealment. The proposed algorithm has two advantages:

• (i) 

  Since DCT does not have the explicit phase information, one does not need the cubic spline interpolation of the phase component of the sinusoidal model.

• (ii) 

  The parameters to be interpolated can be reduced because of the energy packing efficiency of the DCT. This is particularly important if signal synthesis is carried out on a remote location from the transmitted parameters.

The results are presented on periodic waveforms and on speech signal in order to appreciate the fidelity of the proposed algorithm. In addition, the proposed method is compared with TD-PSOLA, sinusoidal model and phase vocoder algorithms. The results are presented in objective PESQ scores for time scale modification and output files are provided as supplementary material,¹ for subjective evaluation, for packet lost concealment. Results prove that the proposed modification of the DCT synthesis provides a favorable algorithm for specialists working in the signal processing area.     

The influence of prototype fidelity and aesthetics of design in usability tests: effects on user behaviour, subjective evaluation and emotion

An empirical study examined the impact of prototype fidelity on user behaviour, subjective user evaluation and emotion. The independent factors of prototype fidelity (paper prototype, computer prototype, fully operational appliance) and aesthetics of design (high vs. moderate) were varied in a between-subjects design. The 60 participants of the experiment were asked to complete two typical tasks of mobile phone usage: sending a text message and suppressing a phone number. Both performance data and a number of subjective measures were recorded. The results suggested that task completion time may be overestimated when a computer prototype is being used. Furthermore, users appeared to compensate for deficiencies in aesthetic design by overrating the aesthetic qualities of reduced fidelity prototypes. Finally, user emotions were more positively affected by the operation of the more attractive mobile phone than by the less appealing one.     

A comparison of tools for teaching formal software verification

We compare four tools regarding their suitability for teaching formal software verification, namely the Frege Program Prover, the Key system, Perfect Developer, and the Prototype Verification System (PVS). We evaluate them on a suite of small programs, which are typical of courses dealing with Hoare-style verification, weakest preconditions, or dynamic logic. Finally we report our experiences with using Perfect Developer in class.     

飞行器性能样机虚拟试验系统研究与实现

为实现航天飞行器研制中性能样机模型的充分利用,提出了飞行器性能样机虚拟试验系统的总体方案,通过试验基础数据库、试验数据管理、验证辅助工具、虚拟试验应用等子系统划分和工作流程设计,提供对虚拟试验的全流程支持。系统突破了试验数据对象化管理、试验流程建模等关键技术,并基于虚拟试验支撑平台VITA完成了相应系统实现,在多个飞行器研制过程中开展了典型应用。     

Comparing three methods for modeling the uncertainty in knowledge discovery from area-class soil maps

Knowledge discovery has been demonstrated as an effective approach to extracting knowledge from existing data sources for soil classification and mapping. Soils are spatial entities with fuzzy boundaries. Our study focuses on the uncertainty associated with class assignments when classifying such entities. We first present a framework of knowledge representation for categorizing spatial entities with fuzzy boundaries. Three knowledge discovery methods are discussed next for extracting knowledge from data sources. The methods were designed to maintain information for modeling the uncertainties associated with class assignments when using the extracted knowledge for classification. In a case study of knowledge discovery from an area-class soil map, all three methods were able to extract knowledge embedded in the map to classify soils at accuracies comparable to that of the original map. The methods were also able to capture membership gradations and helped to identify transitional zones and areas of potential problems on the source map when measures of uncertainties were mapped. Among the three methods compared, a fuzzy decision tree approach demonstrated the best performance in modeling the transitions between soil prototypes.     

Design and validation of an Individual Health Report (IHR)

This research focused on developing a general health report that conveys an individual’s health readings in a clear, concise and explanatory manner and demonstrating the report’s usefulness. The research examined the need for such a report and focused the design on the determined need and communication through visual display. The designed “Individual Health Report (IHR)” was evaluated using data obtained from an online survey developed for this research. The analysis involved t-tests, McNemar’s tests, linear regression and ANOVA. Results included the finding that the IHR significantly improved respondent’s ability to correctly answer questions about their health status and preventive health in general (p < 0.0001, n = 61). The study also showed that introduction of the IHR by healthcare providers would significantly improve the respondents’ view that they get the preventive healthcare information they need to make appropriate decisions (p = 0.0007, n = 61).In an era when costs of healthcare are of great concern and prevention is starting to gain traction as compared to strictly treatment, an IHR could be a very practical and beneficial step toward prevention focused healthcare. An IHR could be considered as a tool to provide increased public awareness of health status, with resulting gains in proactive and effective health management choices.

Relevance to Industry

Degraded health and associated healthcare costs are of significant concerns to industry performance and profits. As several references highlighted in this research have indicated, a lack of health literacy and awareness of critical health indicators are significant concerns in helping employees to manage their own health status. From an economic and societal perspective, it may be considered cost effective for employers to work with healthcare providers to support presentation of employee health status and results of recent healthcare evaluations by means of an IHR. An IHR of the type tested in this research can be seen to both provide clear and understandable health status information, and improve health literacy, for wide sections of the population. Presenting employee information via this type of IHR can effectively supplement healthcare information delivered by healthcare providers. The IHR tested in this research represents a form of clear information presentation and visualization that overcomes issues of jargon that degrades communication between healthcare providers and employees.     

Web应用程序开发探讨

1 引言随着Internet和WWW技术的不断发展,Web的应用日趋广泛。目前,越来越多的公司和企业利用WWW网页作为商品促销或客户服务的手段,基于Web的大规模应用程序不断涌现。然而,由于Web应用程序具有许多与传统的应用程序不同的特点,开发人员往往抛弃传统的软件开发方法,而大量采用了类     

大型MIS系统的复合开发方法

本文介绍了软件开发的生命周期法和快速原型法的基本思想及其局限性,并将两种开发方法相结合,提出了一种大型MIS系统的复合开发方法,以实现快速有效地开发MIS系统。     

原型法在计算机文化普及教育中应用的构想

随着计算机文化的普及,传统的计算机教学模式已逐渐不适应计算机现代教育了。本文在分析了文科类高校传统教学模式弊端的基础上,提出了软件开发方法中的原型法在计算机文化教育中应用的构想,并探讨了该模式下教材的特点,最后分析了该模式的优点。