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31.
对马钢1号高炉降低燃料比的实践进行了总结。通过探索装料制度,调整煤气流分布,改善原燃料条件,维持合理的热制度,建立预警机制等措施,实现了降低燃料消耗的目标,同时维持了高炉的长周期稳定顺行。 相似文献
32.
Ricardo Villar-Ribera Francisco Hernández-AbadJosé Ignacio Rojas-Sola David Hernández-Díaz 《Mechanism and Machine Theory》2011,46(6):820-830
The transmission of information has gone through various stages of evolution throughout its history. A stage before that of the electric telegraph was the so-called aerial/optical telegraph. It was developed towards the end of the 18th century and was in service until the middle of the 19th century. Chappe's system was widely used in France, and was the first to be in consistent use. However, a new and technologically superior system was developed soon afterwards which superseded it. Its inventor was Agustín de Betancourt, considered by some authors one of the founders of the Theory of Machines and Mechanisms, who, together with the distinguished clockmaker Breguet, presented it to the French Authorities in the turbulent decade of the 1790s.This article presents a historical review of this telegraph and analyzes its technical characteristics. It presents analytically, numerically and graphically some of the statements made about the telegraph, and corrects other subsequent observations. Lastly, a detailed reconstruction of the telegraph is made using different advanced CAD techniques, which provide an accurate static and dynamic view of each of its parts. 相似文献
33.
34.
Dimas?Martínez?MoreraEmail author Paulo?Cezar?Carvalho Luiz?Velho 《The Visual computer》2008,24(12):1025-1037
This paper discusses the problem of modeling on triangulated surfaces with geodesic curves. In the first part of the paper
we define a new class of curves, called geodesic Bézier curves, that are suitable for modeling on manifold triangulations. As a natural generalization of Bézier curves, the new curves
are as smooth as possible. In the second part we discuss the construction of C
0 and C
1 piecewise Bézier splines. We also describe how to perform editing operations, such as trimming, using these curves. Special
care is taken to achieve interactive rates for modeling tasks. The third part is devoted to the definition and study of convex
sets on triangulated surfaces. We derive the convex hull property of geodesic Bézier curves.
相似文献
Luiz VelhoEmail: |
35.
A modern problem from aerospace control involves the certification of a large set of potential controllers with either a single plant or a fleet of potential plant systems, with both plants and controllers being MIMO and, for the moment, linear. Experiments on a limited number of controller/plant pairs should establish the stability and a certain level of margin of the complete set. We consider this certification problem for a set of controllers and provide algorithms for selecting an efficient subset for testing. This is done for a finite set of candidate controllers and, at least for SISO plants, for compact infinite set. In doing this, the ν-gap metric will be the main tool. Computational examples are given, including one of certification of an aircraft engine controller. The overarching aim is to introduce truly MIMO margin calculations and to understand their efficacy in certifying stability over a set of controllers and in replacing legacy single-loop gain and phase margin calculations. 相似文献
36.
锅炉控制系统是一个多变量、大时滞、干扰因素多的非线性时变系统,常规控制手段很难达到理想效果.针对燃煤热水锅炉燃烧系统普遍存在热效率低的问题,提出一种以炉膛温度为指标的风煤比模糊自寻优控制算法,并给出了基于西门子PLC的实现方法.实践表明,该方法能有效提高锅炉的热效率,实现锅炉的经济环保运行. 相似文献
37.
Z. Lin E. Goikolea A. Balducci K. Naoi P.L. Taberna M. Salanne G. Yushin P. Simon 《Materials Today》2018,21(4):419-436
Supercapacitors, also known as electrochemical capacitors, have witnessed a fast evolution in the recent years, but challenges remain. This review covers the fundamentals and state-of-the-art developments of supercapacitors. Conventional and novel electrode materials, including high surface area porous carbons for electrical double layer capacitors (EDLCs) and transition metal oxides, carbides, nitrides and their various nanocomposites for pseudocapacitors – are described. Latest characterization techniques help to better understand the charge storage mechanisms in such supercapacitors and recognize their current limitations, while recently proposed synthesis approaches enable various breakthroughs in this field. 相似文献
38.
微弱信号的锁相检测技术是现代电子检测理论中的一种重要方法。而对被测信号进行调制使其与参考信号相关是实现锁相检测的关键。其中利用光学斩光器对被测光进行调制使其与方波参考信号相关是对微弱光信号进行锁相检测的一种常用方法。本文讨论了参考方波信号占空间比及相位抖动对测量信噪比的影响,叙述了参考信号占空比可调的斩光器的设计思想、制作方法和实际效果。 相似文献
39.
Zelong Wang Author Vitae Fengxia Yan Author Vitae Author Vitae Jubo Zhu Author Vitae 《Pattern recognition》2010,43(6):2157-2164
As the development of the technology for radar target recognition, missile target automatic recognition has received considerable attention in recent years. Missile target, compared with the plane target, is hard to recognize for its smallness, feebleness and maneuver. In this paper, a new recognition method based on radar image time-series, which can significantly reduce the recognition time and classification error, is proposed. The image time-series are produced by range instantaneous Doppler imaging algorithm firstly, and then cross-range scaling of the images is processed. In particular, the inertia ratio, extracted from the obtained image time-series, is introduced to distinguish the missile from decoys. Furthermore, the effectiveness of this method is demonstrated by application to simulated data and it has been shown that this method has the potential to be used in a number of real-time applications. 相似文献
40.
Marco Riani 《Computational statistics & data analysis》2010,54(12):3300-3312
The forward search provides data-driven flexible trimming of a Cp statistic for the choice of regression models that reveals the effect of outliers on model selection. An informed robust model choice follows. Even in small samples, the statistic has a null distribution indistinguishable from an F distribution. Limits on acceptable values of the Cp statistic follow. Two examples of widely differing size are discussed. A powerful graphical tool is the generalized candlestick plot, which summarizes the information on all forward searches and on the choice of models. A comparison is made with the use of M-estimation in robust model choice. 相似文献