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21.
This paper introduces the new interactive Java sketching software KamiWaAi, recently developed at the University of Fukui. Its graphical user interface enables the user without any knowledge of both mathematics or computer science, to do full three dimensional “drawings” on the screen. The resulting constructions can be reshaped interactively by dragging its points over the screen. The programming approach is new. KamiWaAi implements geometric objects like points, lines, circles, spheres, etc. directly as software objects (Java classes) of the same name. These software objects are geometric entities mathematically defined and manipulated in a conformal geometric algebra, combining the five dimensions of origin, three space and infinity. Simple geometric products in this algebra represent geometric unions, intersections, arbitrary rotations and translations, projections, distance, etc. To ease the coordinate free and matrix free implementation of this fundamental geometric product, a new algebraic three level approach is presented. Finally details about the Java classes of the new GeometricAlgebra software package and their associated methods are given. KamiWaAi is available for free internet download.  相似文献   
22.
冯源  豆海利  赵刚 《应用声学》2016,24(1):47-47
集成XGATE协处理器内核的S12XE系列双核单片机具有处理速度快、反应时间短、功耗低等优点,在嵌入式应用中具有独特优势和很好的应用前景。本文采用16位双核单片机MC9S12XEQ512作为主控制器,以集成信号和电源隔离功能的CAN收发器芯片ADM3053来实现CAN接口电路,设计并实现了一个可以连接3个CAN通信子网的CAN网关,有效实现了系统的小型化、低功耗、低成本。采用双核处理技术来优化CAN网关的处理流程,由协处理器XGATE来处理各种中断,S12X主CPU则专注于协议处理和消息转发。实际应用表明,系统运行稳定可靠,与传统的采用单处理器实现的CAN网关相比,系统的数据吞吐能力和实时性得到了明显改善。  相似文献   
23.
The current state of using expert system (ES) techniques for statistics is expounded through the difficulties of defining the notion of statistical expert system (SES) and through several well-known examples. The main characteristics of statistical expertise, and particularly the important concept of strategy are emphasized. The current state of SESs is seen in the context of the global trend of the evolution of ES, i.e. within the growth of second generation expert system (SGESs). The knowledge base of these ESs represent an attempt to represent not only experts' knowledge but also the way experts acquire their expertise, thanks to the existence of an underlying model. We show through many examples how far SESs are and/or will be able to be SGESs.  相似文献   
24.
In this research, we investigate stopping rules for software testing and propose two stopping rules from the aspect of software reliability testing based on the impartial reliability model. The impartial reliability difference (IRD-MP) rule considers the difference between the impartial transition-probability reliabilities estimated for both software developer and consumers at their predetermined prior information levels. The empirical–impartial reliability difference (EIRD-MP) rule suggests stopping a software test when the computed empirical transition reliability is tending to its estimated impartial transition reliability. To insure the high-standard requirement for safety-critical software, both rules take the maximum probability (MP) of untested paths into account.  相似文献   
25.
We prove that the observational equivalence of third-order finitary (i.e. recursion-free) Idealized Algol (IA) is decidable using Game Semantics. By modelling the state explicitly in our games, we show that the denotation of a term M of this fragment of IA is a compactly innocent strategy-with-state, i.e. the strategy is generated by a finite view function fM. Given any such fM, we construct a real-time deterministic pushdown automaton (DPDA) that recognizes the complete plays of the knowing-strategy denotation of M. Since such plays characterize observational equivalence, and there is an algorithm for deciding whether any two DPDAs recognize the same language, we obtain a procedure for deciding the observational equivalence of third-order finitary IA. Restricted to second-order terms, the DPDA representation cuts down to a deterministic finite automaton; thus our approach gives a new proof of Ghica and McCusker’s regular-expression characterization for this fragment. Our algorithmic representation of program meanings, which is compositional, provides a foundation for model-checking a wide range of behavioural properties of IA and other cognate programming languages. Another result concerns second-order IA with full recursion: we show that observational equivalence for this fragment is undecidable.  相似文献   
26.
粟智 《光谱实验室》1995,12(5):58-60
本文介绍了光谱仪软件系统的优化处理方法,方法简单、实用。在报告的最后列出了该方法的实用实例。  相似文献   
27.
Powerful response surface methods based on kriging and radial basis function (RBF) interpolation have been developed for expensive, i.e. computationally costly, global nonconvex optimization. We have implemented some of these methods in the solvers rbfSolve and EGO in the TOMLAB Optimization Environment (http://www.tomopt.com/tomlab/). In this paper we study algorithms based on RBF interpolation. The practical performance of the RBF algorithm is sensitive to the initial experimental design, and to the static choice of target values. A new adaptive radial basis interpolation (ARBF) algorithm, suitable for parallel implementation, is presented. The algorithm is described in detail and its efficiency is analyzed on the standard test problem set of Dixon–Szegö. Results show that it outperforms the published results of rbfSolve and several other solvers.  相似文献   
28.
Numerically stable algorithms for quadratic programming are discussed. A new algorithm is described for indefinite quadratic programming which utilizes methods for updating positivedefinite factorizations only. Consequently all the updating procedures required are common to algorithms for linearly-constrained optimization. The new algorithm can be used for the positive-definite case without loss of efficiency.  相似文献   
29.
大功率固态调制器的仿真研究   总被引:2,自引:3,他引:2       下载免费PDF全文
 设计了大功率固态调制器的新型固态脉冲开关模块。通过分析电力电子仿真软件Saber中绝缘栅双极晶体管(IGBT)物理模型的概念和等效电路,结合实验数据建立了IXDH20N120型IGBT的模型,研究了Saber环境下,不同参数条件和拓扑结构对调制器电路输出特性的影响。仿真结果表明:动态均压网络在有效地保护开关的同时,可以减少IGBT的开关损耗;电路中器件离散性与系统分布参数会造成调制器输出波形质量下降,效率降低。并对调制器在负载打火情况下,因严重不均流而损坏器件故障的机理作了分析,实验证明仿真结果和分析与实际相符。  相似文献   
30.
The last few years have seen a significant increase in publicly available software specifically targeted to the analysis of extreme values. This reflects the increase in the use of extreme value methodology by the general statistical community. The software that is available for the analysis of extremes has evolved in essentially independent units, with most forming extensions of larger software environments. An inevitable consequence is that these units are spread about the statistical landscape. Scientists seeking to apply extreme value methods must spend considerable time and effort in determining whether the currently available software can be usefully applied to a given problem. We attempt to simplify this process by reviewing the current state, and suggest future approaches for software development. These suggestions aim to provide a basis for an initiative leading to the successful creation and distribution of a flexible and extensible set of tools for extreme value practitioners and researchers alike. In particular, we propose a collaborative framework for which cooperation between developers is of fundamental importance. AMS 2000 Subject Classification Primary—62P99  相似文献   
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