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141.
介绍气化效率高、有利于环保、具有一定竞争力的Shell煤气化工艺原理、技术特点及关键设备。建议尽快实现关键技术和设备的国产化。 相似文献
142.
143.
1 INTRODUCTIONThe CSP(Corresponding States Principle)has been considered to be a useful methodfor the prediction of fluid properties from a minimum amount of information.One ofits form,the shape factor methods is developed through relating the pVT of any interestedpure fluid"a"to that of another"0"by writing 相似文献
144.
碘和硫增感剂在卤化银颗粒表面的分布*李金培**王素娥(中国科学院感光化学研究所,北京100101)关键词碘化银,硫增感,软硬酸碱原理碘在卤化银微晶中的含量和分布对感光度的影响引起乳剂配方设计者的广泛注意和重视.颗粒中的碘引起其内部结构和表面结构的改变... 相似文献
145.
This paper focuses on the design of a low order robust stabilizer for the tracking/disturbance rejection problem based on the internal model principle in the time-varying setting and its application to the hydraulic pressure tracking with varying frequency. The problem of this kind known as output regulation generally consists of two major parts: internal model unit construction and stabilizer design. While the construction of the time-varying internal model unit is non-trivial by itself and a very recent research outcome enables its synthesis for a class of linear time-varying systems, the effective stabilization of the augmented system (internal model unit and plant) for practical applications remains a challenge. This is due to the need to stabilize the high order time-varying augmented system using a low order stabilizer in a robust fashion and with desirable transient performance. While directly applying the stabilization approaches for a general LTV system will result in a high order stabilizer, a new method is proposed in this paper that overcomes this bottleneck by taking advantage of the unique structure of the internal model based control system. Instead of using a dynamic stabilizer with high order, this approach uses a sequence of time-varying gains that are directly injected into the internal model unit. A critical issue addressed is how to avoid the non-convex optimization associated with the time-varying gain synthesis and then convert the stabilizer design into a series of Linear Matrix Inequalities (LMIs). The proposed control approach is then demonstrated on an electrohydraulic system. 相似文献
146.
This paper investigates a stochastic optimal control problem with delay and of mean-field type, where the controlled state process is governed by a mean-field jump–diffusion stochastic delay differential equation. Two sufficient maximum principles and one necessary maximum principle are established for the underlying system. As an application, a bicriteria mean–variance portfolio selection problem with delay is studied to demonstrate the effectiveness and potential of the proposed techniques. Under certain conditions, explicit expressions are provided for the efficient portfolio and the efficient frontier, which are as elegant as those in the classical mean–variance problem without delays. 相似文献
147.
汽车用塑料注塑新技术的进展 总被引:1,自引:0,他引:1
综述了汽车用塑料的注射成型技术的进展,简单介绍了气体辅助注射成型(GAIM)、水辅助注射成型、熔芯注射成型、反应注射/增强反应注射(RIM/RRIM)成型等技术的特点、生产的汽车部件及最新动向。 相似文献
148.
《Automatica》2014,50(11):2737-2764
Adaptive control is a control methodology capable of dealing with uncertain systems to ensure desired control performance. This paper provides an overview of some fundamental theoretical aspects and technical issues of multivariable adaptive control, and a thorough presentation of various adaptive control schemes for multi-input–multi-output systems, literature reviews on adaptive control foundations and multivariable adaptive control methods, and related technical problems. It covers some basic concepts and issues such as certainty equivalence, stability, tracking, robustness, and parameter convergence. It discusses some of the most important topics of adaptive control: plant uncertainty parametrization, stable controller adaptation, and design conditions for different adaptive control schemes. The paper also presents a detailed study of well-developed multivariable model reference adaptive control theory and design techniques. It provides an introduction to multivariable adaptive pole placement and adaptive nonlinear control, and it concludes by identifying some open research problems. 相似文献
149.
150.