Step response classification for model-based autotuning via polygonal curve approximation

A model-based autotuning method consists of an identification and a regulator tuning phase. To achieve satisfactory performance and robustness, it is advisable that both phases be tailored a priori to the characteristics of the observed process dynamics. Such characteristics include, but are not limited to, the model structure. For example, overdamped and underdamped models with the same pole-zero structure are parametrised and controlled in different ways. Step response data, that are typically used for the identification phase in the autotuning context, can also be pre-processed to reveal those characteristics. This paper presents a step response classification method suitable for the above purpose. The method is based on a polygonal curve approximation technique for data pre-processing, followed by a neural network classifier. Only normalised I/O data are employed, so that the neural network can be trained off-line with simulated data. Simulation results are reported to show the effectiveness of the proposed classification method in terms of the achievable tuning results.     

Using SPIN to Analyse the Tree Identification Phase of the IEEE 1394 High-Performance Serial Bus (FireWire) Protocol

We describe how the tree identification phase of the IEEE 1394 high-performance serial bus (FireWire) protocol is modelled in Promela and verified using SPIN. The verification of arbitrary system configurations is discussed. Received July 2001/Accepted in revised form November 2002 Correspondence and offprint requests to: Alice Miller, Department of Computing Science, University of Glasgow, 17 Lilybank Gardens, Glasgow G12 8QQ, UK. Email: alice@dcs.gla.ac.uk     

根据概率分布建立有源器件的统计模型

给出一种新的统计模型的建立方法。在有源器件物理模型的基础上，通过优化物理模型参数的均值和均方根，使所建立统计模型的Ｓ参数在各个频率上的概率分布逼近测量数据的概率分布。从建立微波ＭＥＳＦＥＴ统计模型的算例结果看出，本方法不仅能比较好地拟合样本Ｓ参数的概率分布，而且提高了计算效率。     

Workflow technology-based monitoring and control for business process and project management

In this paper the application of workflow technology to monitor, control and coordinate business processes and projects is proposed. The conceptual characteristics of processes and projects as well as their management needs in the functions of planning, execution, monitoring and control are compared. The general design of the proposed system is then developed, with an application example. The proposed monitoring and control system provides proactive tracking of the flow of work and information, and of the utilization and commitment of resources. The design supports hierarchical management of the project and/or business process, allowing concerned persons to visualize and to utilize it in different levels of abstraction, as necessary. The application of workflow technology also provides additional benefits in facilitating communication, documentation and re-utilization.     

集成基础结构中应用服务器的研究与开发

通过对集成基础结构中应用服务器的功能需求分析，采用面向对象方法、矩阵理论和Ｐｅｔｒｉ网技术研究了应用服务器系统的实现策略，并依据智能工程理论给出了应用服务器的系统结构。     

漳泽水库最优兴利调度研究

漳泽水库供水能力下降。优化调度方式是提高水库效益的最有效途径。通过采用随机动态规划方法与模拟模型交互运算得到现行控制水位的水库优化调度图。采用同样方法对不同控制水位的水库运行方式进行优化调度，选出的规划水库最优控制水位为汛限水位９０４ ．５ ｍ ，正常高水位９０５ ．５ ｍ 。优化的控制水位方案在保障水库防洪安全的前提下可供给城市生活和工业用水６ ３００ 万ｍ３ ，较现行控制水位下的供水量提高１ ２５５ 万ｍ３ 。但农业用水仍然不足，应采取一定措施给予解决，如对灌区工程进行改造，因地制宜采取不同节水措施和污水回用等。     

Introductory Paper

In today’s competitive market designing of digital systems (hardware as well as software) faces tremendous challenges. In fact, notwithstanding an ever decreasing project budget, time to market and product lifetime, designers are faced with an ever increasing system complexity and customer expected quality. The above situation calls for better and better formal verification techniques at all steps of the design flow. This special issue is devoted to publishing revised versions of contributions first presented at the 12th Advanced Research Working Conference on Correct Hardware Design and Verification Methods (CHARME) held 21–24 October 2003 in L’Aquila, Italy. Authors of well regarded papers from CHARME’03 were invited to submit to this special issue. All papers included here have been suitably extended and have undergone an independent round of reviewing.     

Performance characteristics of a therapeutic ultrasound wire waveguide apparatus

Therapeutic ultrasound angioplasty has been investigated, clinically, by a number of researchers and represents a potentially promising therapy for the treatment of atherosclerotic lesions. To date, there has been no detailed analysis of the effect of mechanical design parameters, such as wire geometry or damping characteristics, on wire waveguide performance. An apparatus capable of delivering therapeutic ultrasound down small diameter nickel–titanium (NiTi) wire waveguides is described. The output peak-to-peak (p–p) displacements at the distal tip of a 1.0 mm diameter waveguide were measured experimentally, by means of an optical microscope and image analysis software. The output was measured for a range of waveguide lengths from 118 to 303 mm. Wire waveguide distal tip displacements as high as 98 μm (p–p) at 23.5 kHz were measured. For the range of lengths tested, the experimental measurements show the critical relationship between the length of the waveguide and the output distal tip displacements. A finite element model that can predict the resonant frequencies and distal tip displacements of various wire waveguide geometries and configurations, including the effect of damping, is presented. This numerical model has been validated against the experimental displacement data obtained. This will be a valuable design tool for ensuring the safety and effectiveness of therapeutic ultrasound angioplasty procedures.     

Adding Support for Persistence to CLOS via Its Metaobject Protocol

Language-level support for object persistence frees programmers from having to confront a broad class of database issues from within their applications. By virtue of its metaobject protocol, CLOS is a language whose semantics can be tailored by individual programmers. We used the metaobject protocol to extend CLOS with support for object persistence. Our goal was to obtain a version of CLOS with persistence to which we could easily port a commercial geometric CAD modeling system. We describe the design and implementation of our persistence extension and highlight the strengths and weaknesses exhibited by the CLOS metaobject protocol during our experiment. For many aspects of the implementation we found that the metaobject protocol was ideal. In other cases we had to choose among paying a large performance penalty, extending the protocol, and bypassing the protocol by modifying the language implementation directly.