Stabilization of a class of fuzzy stochastic jump systems with partial information on jump and sojourn parameters

This paper addresses the problem of the design of controller for fuzzy semi-Markov jump systems with hidden modes against the incomplete information on probability density functions of sojourn time. Two ubiquitous circumstances in practice are taken into account, which are often ignored in other related work:(1) the phenomenon that system modes cannot be accessed entirely is considered proactively;(2) finitely accessible information on probability density functions is studied in this paper. By virtue of hidden semi-Markov chain, the underlying systems are modeled as hidden semi-Markov jump systems, which are more general than semi-Markov jump systems. Sufficient conditions on the existence of desired accessible-mode-dependent fuzzy controller are derived such that the fuzzy hidden semi-Markov jump systems is mean square stable. Based on the emission probability matrix, the presented control policy overcomes the possible mode-mismatch between the system mode and the accessible mode.Finally, an example is provided to demonstrate the effectiveness of the proposed control method.     

Sensing characterization of Sn/In/Ti nanocomplex oxides for CO,CH<Subscript>4</Subscript> and NO<Subscript>2</Subscript>

The nanocomplex oxides of Sn-In and Sn-In-Ti were prepared by controlled co-precipitation method as sensing materials of semiconductor gas sensors for detection of CO, CH4 and NO2. Through manipulating the Sn/In cation ratio, metal salt total concentration, precipitation pH value and aging time, the nanocrystalline powders were successfully derived with chemical homogeneity and superior thermal stability, compared with the single component oxides. The particle size and morphology, surface area, and thermal and phase stabilities were characterized using TEM, TG-DTA, BET and XRD. The sensing tests showed that the Sn-In composites exhibit high sensitivity and selectivity for CO and NO2. The introduction of TiO2 enhanced CH4 sensitivity and selectivity, particularly, additives of Pd and Al2O3 as a dopant and surface modification greatly enhanced the sensing properties. The sensitivity depended on the composition of composites, calcination temperature and operating temperature. The optimal values were (25%In2O3- 75%SnO2)-20%TiO2 for ternary composite, 600 and 300℃, respectively. Temperature-programmed desorption (TPD) studies were employed to explain the gas adsorption behavior displayed by the surface of nanocomposites and X-ray photoelectron spectroscopic (XPS) analysis was used to confirm the electronic interactions existing between oxide components. The sensing mechanism of the nanocomposites was attributed to chemical and electronic synergistic effects.     

2000年度压力容器制造许可证换证检查中发现问题的总结

受国家质量技术监督局锅炉压力容器安全监察局的委托,中国化工装备协会对2000年压力容器制造许可证换证单位中的30个企业进行了换证检查。这次检查的主要依据是“(2000)质技监锅便字第3090号文”和《锅炉压力容器制造单位资格认可与管理规则》(以下称《规则》)等文件、法规。检查工作分五个小组于2000年7月19日开始至8月31日结束。检查组本着对国家质量技术监     

铜版纸的质量及对原纸的要求浅析

铜版纸作为发展最快的纸张品种之一受到了广泛的关注,该文概括了铜版纸的重要性质,对其影响因素进行分析,指出了铜版原纸对铜版纸质量的重要性,对原纸的质量要求进行了分析、总结,并展望了铜版纸的未来。     

蛋糕防霉措施的研究

本研究证实单独使用丙酸钠或富马酸防霉效果不理想,而使用复合防霉剂—丙酸钠加柠檬酸和丙酸钠加富马酸二甲酯能使蛋糕在夏天的霉变发生期推迟到六天以后。本复合防霉剂可用于蛋糕和月饼生产。本文在实验研究的基础上,对防霉机理提出了新见解一反馈抑制作用。     

Fundamental study of CO<Subscript>2</Subscript> control technologies and policies in China

The technical roadmap and policies for CO₂ mitigation suitable for China are a common center of attention in the fields of energy, environment, and management science in the country. Emphasizing interaction between technical research and policy research, this work discovers the potential breakthrough in the integrated field. The technical difficulties of recovering CO₂ are pointed out, the mechanism of combining CO₂ recovery with energy conversion is investigated, and the basic principle for integrating an environmental-friendly energy system is discussed. Moreover, the formulation of a new energy system that can recover CO₂ with very low or even zero energy penalty is proposed, while the assessment methodology and model system for the technical roadmap of CO₂ emission control are developed. Finally, a new technical roadmap constructing an energy network suitable for China is proposed, which may provide a new way for the development of sustainable energy and environment technologies. Supported by the major international cooperation projects of the National Natural Science Foundation of China (Grant No. 50520140517)     

Sensing characterization of Sn/In/Ti nanocomplex oxides for CO, CH_4 and NO_2

The nanocomplex oxides of Sn-In and Sn-In-Ti were prepared by controlled co-precipitation method as sensing materials of semiconductor gas sensors for detection of CO, CH4 and NO2. Through manipulating the Sn/In cation ratio, metal salt total concentration, precipitation pH value and aging time, the nanocrystalline powders were successfully derived with chemical homogeneity and superior thermal stability, compared with the single component oxides. The particle size and morphology, surface area, and thermal and phase stabilities were characterized using TEM, TG-DTA, BET and XRD. The sensing tests showed that the Sn-In com-posites exhibit high sensitivity and selectivity for CO and NO2. The introduction of TiO2 enhanced CH4 sensitivity and selectivity, particularly, additives of Pd and Al2O3 as a dopant and surface modification greatly enhanced the sensing properties. The sensitivity depended on the composition of composites, calcination temperature and operating temperature. The optimal values were (25%In2O3- 75%SnO2)-20%TiO2 for ternary composite, 600 and 300℃, respectively. Temperature-programmed de-sorption (TPD) studies were employed to explain the gas adsorption behavior dis-played by the surface of nanocomposites and X-ray photoelectron spectroscopic (XPS) analysis was used to confirm the electronic interactions existing between oxide components. The sensing mechanism of the nanocomposites was attributed to chemical and electronic synergistic effects.