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排序方式: 共有208条查询结果,搜索用时 31 毫秒
81.
针对塔康导航系统的测试需求,结合软件无线电技术,设计并实现了塔康信号模拟系统。首先介绍了塔康导航台导航的原理,包括:测向原理和测距原理。接着,根据塔康导航台信号的特点,给出信号模拟系统的需求分析。在需求分析的基础上,完成了信号模拟系统的总体方案设计、硬件结构组成及软件的模块化设计。然后,根据塔康信号模拟系统信号的模块化设计,对各个模拟信号模块进行详细设计,并在GNU Radio上编程实现。最后,搭建了信号模拟系统测试试验平台,在平台上完成了模拟系统各个信号模块的测试验证,并对塔康信号模拟系统进行了功能试验验证。 相似文献
82.
Limin Shao 《大学化学》2020,35(2):107-113
A statistical software package is developed for the course of chemical analysis. The software calculates cumulative distribution functions and inverse cumulative distribution functions of normal, t, χ2, and F distributions; it also provides critical values for tests of statistical significance. The software is designed to substitute for traditional data tables that are insufficient and obscure. Statistical problems can be solved more efficiently with the software than with traditional data tables, which enables students to focus on understanding statistical principles and interpreting results. The software provides information through an intuitive interface, a graph, and natural interactions. Both Matlab and Android versions are presented, and free of charge. 相似文献
83.
Over the past three decades, many software reliability models with different parameters, reflecting various testing characteristics, have been proposed for estimating the reliability growth of software products. We have noticed that one of the most important parameters controlling software reliability growth is the fault reduction factor (FRF) proposed by Musa. FRF is generally defined as the ratio of net fault reduction to failures experienced. During the software testing process, FRF could be influenced by many environmental factors, such as imperfect debugging, debugging time lag, etc. Thus, in this paper, we first analyze some real data to observe the trends of FRF, and consider FRF to be a time-variable function. We further study how to integrate time-variable FRF into software reliability growth modeling. Some experimental results show that the proposed models can improve the accuracy of software reliability estimation. Finally, sensitivity analyses of various optimal release times based on cost and reliability requirements are discussed. The analytic results indicate that adjusting the value of FRF may affect the release time as well as the development cost. 相似文献
84.
This paper presents a conceptual framework and a mathematical formulation for software resource allocation and project selection at the level of software skills. First, we introduce a skill-based framework that considers universities, software companies, and potential projects of a country. Based on this framework, we formulate a linear integer program PMax which determines the selection of projects and the allocation of human resources that maximize profit for a certain company. We show that PMax is NP-complete. Therefore, we devise a meta-heuristic, called Tabu Select and Greedily Allocate (TSGA), to overcome the computational complexities. When compared to PMax running on CPLEX, TSGA performs 15 times faster with an accuracy of 98% on small to large size problems where CPLEX converges. On larger problems where CPLEX does not return an answer, TSGA computes a feasible solution in the order of minutes. 相似文献
85.
J. C. Hadler S. R. Paulo P. J. Iunes C. A. Tello S M. L. Balestrieri G. Bigazzi E. A. C. Curvo P. Hackspacher 《Radiation measurements》2001,34(1-6):149-154
In this work a software developed in the Instituto de Física Gleb Wataghin, IFGW, UNICAMP, Campinas, SP, Brazil for obtaining thermal histories using apatite fission track analysis is presented. This software works in Microsoft-Windows environment. It will be freely disposable in the web site of the Departamento de Raios Cósmicos, IFGW, UNICAMP. Thermal histories obtained through this software are compared with those deduced using Monte Trax the software compatible with Apple Macintosh developed by Gallagher. 相似文献
86.
地质工程自动监测系统由于其监测对象的复杂多变性 ,同一般自动监测系统相比 ,有着显著的差别。其软件系统必须具备与地质体稳定性评价、分析和预测及实时安全预警等相适应的功能。此外 ,为了适应现代化工程建设的要求 ,还应具备先进的智能化和网络化等功能。为此 ,本文通过对地质工程自动监测系统的功能和组成、当前的发展趋势、所涉及到一些关键软件技术问题等的讨论 ,着重总结了作者有关地质工程自动监测软件系统关键技术问题的研究。最后对作者在大量的关键技术问题研究和地质工程变形与破坏特征研究的基础上 ,所开发的大型水电边坡工程自动监测软件系统的功能和特色进行了介绍。 相似文献
87.
Adriaan Peeters Kris Coolsaet Gunnar Brinkmann Nicolas Van Cleemput Veerle Fack 《Journal of mathematical chemistry》2009,45(2):471-477
GrInvIn (Graph Invariant Investigator) is a software framework for teaching graph theory and for research in graph theory and graph theoretic chemistry.
It enables users to construct graphs, compute invariants (e.g. topological indices in chemistry) and investigate relations
between these concepts. The design of GrInvIn emphasizes easy usage and makes use of software engineering techniques that
enable the user to easily extend the system (e.g. by adding new topological indices to investigate). 相似文献
88.
The scale at which MS‐ and NMR‐based platforms generate metabolomics datasets for both research, core, and clinical facilities to address challenges in the various sciences—ranging from biomedical to agricultural—is underappreciated. Thus, metabolomics efforts spanning microbe, environment, plant, animal, and human systems have led to continual and concomitant growth of in silico resources for analysis and interpretation of these datasets. These software tools, resources, and databases drive the field forward to help keep pace with the amount of data being generated and the sophisticated and diverse analytical platforms that are being used to generate these metabolomics datasets. To address challenges in data preprocessing, metabolite annotation, statistical interrogation, visualization, interpretation, and integration, the metabolomics and informatics research community comes up with hundreds of tools every year. The purpose of the present review is to provide a brief and useful summary of more than 95 metabolomics tools, software, and databases that were either developed or significantly improved during 2017–2018. We hope to see this review help readers, developers, and researchers to obtain informed access to these thorough lists of resources for further improvisation, implementation, and application in due course of time. 相似文献
89.
The objective of studying software reliability is to assist software engineers in understanding more of the probabilistic nature of software failures during the debugging stages and to construct reliability models. In this paper, we consider modeling of a multiplicative failure rate whose components are evolving stochastically over testing stages and discuss its Bayesian estimation. In doing so, we focus on the modeling of parameters such as the fault detection rate per fault and the number of faults. We discuss how the proposed model can account for “imperfect debugging” under certain conditions. We use actual inter-failure data to carry out inference on model parameters via Markov chain Monte Carlo methods and present additional insights from Bayesian analysis. 相似文献
90.
Software as a service (SaaS) has moved quickly from a peripheral idea to a mainstream phenomenon. By bundling a software product with delivery and maintenance service, SaaS providers can effectively differentiate their products with traditional shrink-wrap software (SWS). This research uses a game theoretical approach to examine short- and long-term competition between SaaS and SWS providers. We analyze the factors that affect equilibrium outcomes, including user implementation costs, SaaS provider’s operation efficiency, and quality improvement over time. Bundling software with service lowers software implementation cost for users, and our results suggest that it increases equilibrium prices. In providing software services, SaaS providers have to incur significant operation cost. In the long run, service operation cost may significantly affect SaaS firm’s ability to improve its software quality. 相似文献