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1.
The objective of this note is to propose a method for stabilization of structurally fixed modes in expansions of LTI dynamic systems in the scope of overlapping decentralized control design based on the expansion/contraction framework, enabling successful design for a broader class of problems than considered so far. The method is based on a judicious choice of complementary matrices in the expanded space. Numerical examples are provided to illustrate simplicity and efficiency of the proposed approach.  相似文献   
2.
赵志良 《山西建筑》2004,30(21):108-109
介绍了引黄工程五座泵站的火灾自动报警系统的组成及功能,对泵站的火灾探测系统、报警系统、联动控制系统、灭火系统、控制台等原理进行了详细说明,供同行参考借鉴。  相似文献   
3.
微波干燥原理及其应用   总被引:31,自引:1,他引:30  
祝圣远  王国恒 《工业炉》2003,25(3):42-45
介绍了微波干燥的原理和主要特点及其应用的现状,并且给出了微波干燥经济核算的计算方法。  相似文献   
4.
赵丰年 《衡器》2008,37(2):22-25
阐述静态电子轨道衡诸多优点;工作原理、允许误差及误差分配;轨道衡的结构组成部分、解析各部分的工作特性及技术指标要求;合理选配及推荐实例.  相似文献   
5.
We consider a stochastic control problem with linear dynamics with jumps, convex cost criterion, and convex state constraint, in which the control enters the drift, the diffusion, and the jump coefficients. We allow these coefficients to be random, and do not impose any Lp-bounds on the control.

We obtain a stochastic maximum principle for this model that provides both necessary and sufficient conditions of optimality. This is the first version of the stochastic maximum principle that covers the consumption–investment problem in which there are jumps in the price system.  相似文献   

6.
In a recent discovery, coaxial electrospinning was explored to encapsulate living organisms within a continuous bio‐polymeric microthread from which active biological scaffolds were fabricated (Townsend‐Nicholson and Jayasinghe, Biomacromolecules 2006, 7, 3364). The cells were demonstrated to have gone through all expected cellular activity without their viability being compromised. These biologically active threads and scaffolds have direct and tremendous applicability from regenerative to therapeutic medicine. Currently these post‐processed cells as composite threads and scaffolds are being investigated in‐depth at a cellular level to establish if the processing methodology has any affect on the cellular make‐up. We now demonstrate a competing non‐electric field driven approach for fabricating composite threads and scaffolds influenced only by a differential pressure. We refer to this novel composite thread to scaffold fabrication methodology as coaxial aerodynamically assisted bio‐threading (CAABT). Our investigations firstly, demonstrate that this technique can process handle living organisms without biologically perturbing them in anyway. Secondly the process is elucidated as possessing the ability to form composite active threads from which biologically viable scaffolds are formed. Finally our study employs florescent activated cell sorting (FACScan), a method by which the cellular dynamics and viability are quantified on control and threaded cellular samples at two prescribed time points. In parallel with FACScan, optical comparison of cellular morphology at three time points within a period of three weeks is carried out to photographically observe any changes in the post‐processed cellular phenotype. Our developmental investigations into this novel aerodynamically assisted threading methodology has unearthed a unique biomicrofabrication approach, which joins cell electrospinning in the cell threading to scaffold fabrication endeavor. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
7.
This paper presents a single lossless inductive snubber‐assisted ZCS‐PFM series resonant DC‐DC power converter with a high‐frequency high‐voltage transformer link for industrial‐use high‐power magnetron drive. The current flowing through the active power switches rises gradually at a turned‐on transient state with the aid of a single lossless snubber inductor, and ZCS turn‐on commutation based on overlapping current can be achieved via the wide range pulse frequency modulation control scheme. The high‐frequency high‐voltage transformer primary side resonant current always becomes continuous operation mode, by electromagnetic loose coupling design of the high‐frequency high‐voltage transformer and the magnetizing inductance of the high‐frequency high‐voltage transformer. As a result, this high‐voltage power converter circuit for the magnetron can achieve a complete zero current soft switching under the condition of broad width gate voltage signals. Furthermore, this high‐voltage DC‐DC power converter circuit can regulate the output power from zero to full over audible frequency range via the two resonant frequency circuit design. Its operating performances are evaluated and discussed on the basis of the power loss analysis simulation and the experimental results from a practical point of view. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 153(3): 79–87, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20126  相似文献   
8.
荧光染料用于涤纶织物染色的荧光性能研究   总被引:4,自引:0,他引:4  
杨文芳  周微 《染料与染色》2004,41(4):206-208
在实验条件下,染色织物的荧光反射率随荧光染料的浓度增加而增加,超过一定浓度后,有下降趋势;在pH=5左右,荧光反射率最高;荧光增白剂会提高染色织物的荧光反射率,在荧光黄2GFL中,当荧光增白剂的浓度由0.1%增加到5%时,荧光反射率由8.43增加至18.59,而对非荧光染料只有增艳的作用,不产生荧光。荧光染料染色织物的荧光反射率随着加入非荧光染料量的增加而减弱。  相似文献   
9.
Fenton氧化法处理废水的机理及应用   总被引:14,自引:0,他引:14  
张玲玲  李亚峰  孙明  张小颖 《辽宁化工》2004,33(12):734-737
阐述了Fenton试剂的氧化机理 ,分析了各项因素对氧化效果的影响。介绍了光 -Fenton法、电 -Fenton法及Fenton -混凝法在废水处理中应用情况以及存在的问题 ,并展望了其发展趋势。  相似文献   
10.
改性膨润土对甲基橙的吸附   总被引:4,自引:0,他引:4  
胡巧开 《染料与染色》2004,41(5):304-306
在用Cu^2 A‘^3 Fe^3 对膨润土改性中,Fe^3 改性的膨润土对甲基橙的吸附性能最好,在振荡20分钟后即可达到吸附平衡。pH=3~7、用量为3g/L、25℃时对甲基橙的吸附量达到最大,在pH=7及常温条件下,铁基膨润土的用量为11g/L时,对浓度为250mg/L甲基橙的吸附量和去除率分别为22.2mg/g98.6%;对浓度为40mg/L的甲基橙去除率达97.1%。  相似文献   
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