In this paper, a labelled transition semantics for higher-order processcalculi is studied. The labelled transition semantics is relatively clean and simple, andcorresponding bisimulation equivalence can be easily form...In this paper, a labelled transition semantics for higher-order processcalculi is studied. The labelled transition semantics is relatively clean and simple, andcorresponding bisimulation equivalence can be easily formulated based on it. And the congruenceproperties of the bisimulation equivalence can be proved easily. To show the correspondence betweenthe proposed semantics and the well-established ones, the bisimulation is characterized as a versionof barbed equivalence and a version of context bisimulation.展开更多
Modal logic characterization in a higher-order setting is usually not a trivial task because higher-order process-passing is quite different from first-order name-passing. We study the logical characterization of high...Modal logic characterization in a higher-order setting is usually not a trivial task because higher-order process-passing is quite different from first-order name-passing. We study the logical characterization of higherorder processes constrained by linearity. Linearity respects resource-sensitiveness and does not allow processes to duplicate themselves arbitrarily. We provide a modal logic that characterizes linear higher-order processes,particularly the bisimulation called local bisimulation over them. More importantly, the logic has modalities for higher-order actions downscaled to resembling first-order ones in Hennessy-Milner logic, based on a formulation exploiting the linearity of processes.展开更多
Invertibility is one of the desirable properties of moving average processes. This study derives consequences of the invertibility condition on the parameters of a moving average process of order three. The study also...Invertibility is one of the desirable properties of moving average processes. This study derives consequences of the invertibility condition on the parameters of a moving average process of order three. The study also establishes the intervals for the first three autocorrelation coefficients of the moving average process of order three for the purpose of distinguishing between the process and any other process (linear or nonlinear) with similar autocorrelation structure. For an invertible moving average process of order three, the intervals obtained are , -0.5ρ2ρ1<0.5.展开更多
Statistics of order 2 (variance, auto and cross-correlation functions, auto and cross-power spectra) and 3 (skewness, auto and cross-bicorrelation functions, auto and cross-bispectra) are used to analyze the wave-part...Statistics of order 2 (variance, auto and cross-correlation functions, auto and cross-power spectra) and 3 (skewness, auto and cross-bicorrelation functions, auto and cross-bispectra) are used to analyze the wave-particle interaction in space plasmas. The signals considered here are medium scale electron density irregularities and ELF/ULF electrostatic turbulence. Nonlinearities are mainly observed in the ELF range. They are independently pointed out in time series associated with fluctuations in electronic density and in time series associated with the measurement of one electric field component. Peaks in cross-bicorrelation function and in mutual information clearly show that, in well delimited frequency bands, the wave-particle interactions are nonlinear above a certain level of fluctuations. The way the energy is transferred within the frequencies of density fluctuations is indicated by a bi-spectra analysis.展开更多
This paper addresses the problem of adaptively estimating the consistent parameters for non Gaussian nonminimum MA processes with symmetric PDF using the fourth order cumulant of the underlying processes. The process...This paper addresses the problem of adaptively estimating the consistent parameters for non Gaussian nonminimum MA processes with symmetric PDF using the fourth order cumulant of the underlying processes. The processes may be corrupted by additive noise.展开更多
The finite data estimates of the complex fourth-order moments of a signal consisting of random harmonics are analyzed. Conditions for the fourth-order stationarity and ergodicity are obtained. Explicit formulas for th...The finite data estimates of the complex fourth-order moments of a signal consisting of random harmonics are analyzed. Conditions for the fourth-order stationarity and ergodicity are obtained. Explicit formulas for the estimation error and its variance, as well as their limiting large sample values are derived. Finally, a special case relevant to cubic phase coupling is considered, and these results are stated for this case, the variance is shown to comprise an ergodic and a nonergodic part.展开更多
Four phenoxysilicon networks for nonlinear optical (NLO) applications were designed and prepared by an extended sol-gel process without additional H2O and catalyst. All poled polymer network films possess high second-...Four phenoxysilicon networks for nonlinear optical (NLO) applications were designed and prepared by an extended sol-gel process without additional H2O and catalyst. All poled polymer network films possess high second-order nonlinear optical coefficients (d(33)) Of 10(-7)similar to 10(-8) esu. The investigation of NLO temporal stability at room temperature and elevated temperature (120 degreesC) indicated that these films exhibit high d(33) stability because the orientation of the chromophores are locked in the phenoxysilicon organic/inorganic networks.展开更多
随着可再生能源接入电网比例的逐步增大,热力发电厂需要应对更加频繁、更大范围的负荷变化,给电厂的高阶大惯性过热汽温过程的控制带来严峻的挑战。为此,文中针对一类高阶大惯性过热汽温过程,提出一种基于相位补偿的自抗扰控制(phase co...随着可再生能源接入电网比例的逐步增大,热力发电厂需要应对更加频繁、更大范围的负荷变化,给电厂的高阶大惯性过热汽温过程的控制带来严峻的挑战。为此,文中针对一类高阶大惯性过热汽温过程,提出一种基于相位补偿的自抗扰控制(phase compensation based active disturbance rejection control,PC-ADRC)方法。首先,阐述过热汽温系统的工作原理和控制难点。然后,采用低频近似法详细推导相位补偿(phase compensation,PC)网络模型,提出采用PC网络对模型动态特性进行补偿,得到等效降阶模型的简化思路。为便于工程应用,给出PC-ADRC系统的简单实现方法和等效模型分析。最后,对PC-ADRC系统的稳定性和鲁棒性进行研究。理论分析和仿真结果表明,所提出的PC-ADRC系统能有效提升高阶过程控制系统的鲁棒性和快速响应能力。展开更多
Conventional PI control encounters some problems when dealing with large lag process in the presence of parameter uncertainties.For the typical first-order process,an observerbased linear active disturbance rejection ...Conventional PI control encounters some problems when dealing with large lag process in the presence of parameter uncertainties.For the typical first-order process,an observerbased linear active disturbance rejection control(LADRC) scheme is presented to cope with the difficulties,and a reduced-order observer scheme is proposed further.Some quantitative dynamic results with regard to non-overshoot characteristics are obtained.Finally,the performance boundaries of LADRC and PI control are explicitly compared with each other,which shows that the former is more superior in most cases.展开更多
This paper addresses a unified approach of the PID controller design for low as well as high order unstable processes with time delay.The design method is based on the direct synthesis(DS)approach to achieve the enhan...This paper addresses a unified approach of the PID controller design for low as well as high order unstable processes with time delay.The design method is based on the direct synthesis(DS)approach to achieve the enhanced load disturbance rejection.To improve the servo response,a two-degree of freedom control scheme has been considered.A suitable guideline has been provided to select the desired reference model in the DS scheme.The direct synthesis controller has been approximated to the PID controller using the frequency response matching method.A consistently better performance has been obtained in comparison with the recently reported methods.展开更多
目前储能技术路线多样,不同类型的储能各具应用前景,但储能选型需要综合考虑经济性、安全性等因素,是一个复杂的多目标决策问题,因此储能选型是工程应用中的关键问题之一。提出一种将层次分析法(analytic hierarchy process,AHP)和优劣...目前储能技术路线多样,不同类型的储能各具应用前景,但储能选型需要综合考虑经济性、安全性等因素,是一个复杂的多目标决策问题,因此储能选型是工程应用中的关键问题之一。提出一种将层次分析法(analytic hierarchy process,AHP)和优劣解距离法(technique for order preference by similarity to ideal solution,TOPSIS)-模糊综合分析法相结合的储能选型评价体系。首先,通过建立评价体系的判断矩阵,利用AHP获取指标权重;其次,将判断矩阵里量纲不同的指标类型用TOPSIS做规范化处理,以此获得更客观的权重向量,改善AHP法的主观性;而后,将指标权重对角化处理并与标准化后的矩阵相乘获得加权判断矩阵,并求取贴近度向量。最后,加权判断矩阵与模糊综合分析法关系矩阵相乘获取储能类型的隶属度评价结果,并以隶属度最大值所在的等级为最终评价,处于等级Ⅰ中最佳,等级Ⅱ次之并以此类推;由此通过TOPSIS获得更客观的权重向量,改善AHP法的主观性,得到的权重向量也更客观。最后以锂离子电池、钠硫电池和铅酸电池等七种储能类型在应用于削峰填谷、电网保供电和改善电压质量场景为例,并与现有的储能选型方法进行比较,体现该评价体系的创新,检验所提评价体系和选型方法的有效性。展开更多
文摘In this paper, a labelled transition semantics for higher-order processcalculi is studied. The labelled transition semantics is relatively clean and simple, andcorresponding bisimulation equivalence can be easily formulated based on it. And the congruenceproperties of the bisimulation equivalence can be proved easily. To show the correspondence betweenthe proposed semantics and the well-established ones, the bisimulation is characterized as a versionof barbed equivalence and a version of context bisimulation.
基金the National Natural Science Foundation of China(Nos.61202023,61261130589 and61173048)the PACE Project(No.12IS02001)the Specialized Research Fund for the Doctoral Program of Higher Edueation of China(No.20120073120031)
文摘Modal logic characterization in a higher-order setting is usually not a trivial task because higher-order process-passing is quite different from first-order name-passing. We study the logical characterization of higherorder processes constrained by linearity. Linearity respects resource-sensitiveness and does not allow processes to duplicate themselves arbitrarily. We provide a modal logic that characterizes linear higher-order processes,particularly the bisimulation called local bisimulation over them. More importantly, the logic has modalities for higher-order actions downscaled to resembling first-order ones in Hennessy-Milner logic, based on a formulation exploiting the linearity of processes.
文摘Invertibility is one of the desirable properties of moving average processes. This study derives consequences of the invertibility condition on the parameters of a moving average process of order three. The study also establishes the intervals for the first three autocorrelation coefficients of the moving average process of order three for the purpose of distinguishing between the process and any other process (linear or nonlinear) with similar autocorrelation structure. For an invertible moving average process of order three, the intervals obtained are , -0.5ρ2ρ1<0.5.
文摘Statistics of order 2 (variance, auto and cross-correlation functions, auto and cross-power spectra) and 3 (skewness, auto and cross-bicorrelation functions, auto and cross-bispectra) are used to analyze the wave-particle interaction in space plasmas. The signals considered here are medium scale electron density irregularities and ELF/ULF electrostatic turbulence. Nonlinearities are mainly observed in the ELF range. They are independently pointed out in time series associated with fluctuations in electronic density and in time series associated with the measurement of one electric field component. Peaks in cross-bicorrelation function and in mutual information clearly show that, in well delimited frequency bands, the wave-particle interactions are nonlinear above a certain level of fluctuations. The way the energy is transferred within the frequencies of density fluctuations is indicated by a bi-spectra analysis.
文摘This paper addresses the problem of adaptively estimating the consistent parameters for non Gaussian nonminimum MA processes with symmetric PDF using the fourth order cumulant of the underlying processes. The processes may be corrupted by additive noise.
文摘The finite data estimates of the complex fourth-order moments of a signal consisting of random harmonics are analyzed. Conditions for the fourth-order stationarity and ergodicity are obtained. Explicit formulas for the estimation error and its variance, as well as their limiting large sample values are derived. Finally, a special case relevant to cubic phase coupling is considered, and these results are stated for this case, the variance is shown to comprise an ergodic and a nonergodic part.
文摘Four phenoxysilicon networks for nonlinear optical (NLO) applications were designed and prepared by an extended sol-gel process without additional H2O and catalyst. All poled polymer network films possess high second-order nonlinear optical coefficients (d(33)) Of 10(-7)similar to 10(-8) esu. The investigation of NLO temporal stability at room temperature and elevated temperature (120 degreesC) indicated that these films exhibit high d(33) stability because the orientation of the chromophores are locked in the phenoxysilicon organic/inorganic networks.
文摘随着可再生能源接入电网比例的逐步增大,热力发电厂需要应对更加频繁、更大范围的负荷变化,给电厂的高阶大惯性过热汽温过程的控制带来严峻的挑战。为此,文中针对一类高阶大惯性过热汽温过程,提出一种基于相位补偿的自抗扰控制(phase compensation based active disturbance rejection control,PC-ADRC)方法。首先,阐述过热汽温系统的工作原理和控制难点。然后,采用低频近似法详细推导相位补偿(phase compensation,PC)网络模型,提出采用PC网络对模型动态特性进行补偿,得到等效降阶模型的简化思路。为便于工程应用,给出PC-ADRC系统的简单实现方法和等效模型分析。最后,对PC-ADRC系统的稳定性和鲁棒性进行研究。理论分析和仿真结果表明,所提出的PC-ADRC系统能有效提升高阶过程控制系统的鲁棒性和快速响应能力。
基金supported by the National Natural Science Foundation of China(60774088)the National High Technology Research and Development Program of China(863 Program)(2009AA04Z132)the Specialized Research Fund for the Doctoral Program of Higher Education of China(20090031110029)
文摘Conventional PI control encounters some problems when dealing with large lag process in the presence of parameter uncertainties.For the typical first-order process,an observerbased linear active disturbance rejection control(LADRC) scheme is presented to cope with the difficulties,and a reduced-order observer scheme is proposed further.Some quantitative dynamic results with regard to non-overshoot characteristics are obtained.Finally,the performance boundaries of LADRC and PI control are explicitly compared with each other,which shows that the former is more superior in most cases.
文摘This paper addresses a unified approach of the PID controller design for low as well as high order unstable processes with time delay.The design method is based on the direct synthesis(DS)approach to achieve the enhanced load disturbance rejection.To improve the servo response,a two-degree of freedom control scheme has been considered.A suitable guideline has been provided to select the desired reference model in the DS scheme.The direct synthesis controller has been approximated to the PID controller using the frequency response matching method.A consistently better performance has been obtained in comparison with the recently reported methods.
文摘目前储能技术路线多样,不同类型的储能各具应用前景,但储能选型需要综合考虑经济性、安全性等因素,是一个复杂的多目标决策问题,因此储能选型是工程应用中的关键问题之一。提出一种将层次分析法(analytic hierarchy process,AHP)和优劣解距离法(technique for order preference by similarity to ideal solution,TOPSIS)-模糊综合分析法相结合的储能选型评价体系。首先,通过建立评价体系的判断矩阵,利用AHP获取指标权重;其次,将判断矩阵里量纲不同的指标类型用TOPSIS做规范化处理,以此获得更客观的权重向量,改善AHP法的主观性;而后,将指标权重对角化处理并与标准化后的矩阵相乘获得加权判断矩阵,并求取贴近度向量。最后,加权判断矩阵与模糊综合分析法关系矩阵相乘获取储能类型的隶属度评价结果,并以隶属度最大值所在的等级为最终评价,处于等级Ⅰ中最佳,等级Ⅱ次之并以此类推;由此通过TOPSIS获得更客观的权重向量,改善AHP法的主观性,得到的权重向量也更客观。最后以锂离子电池、钠硫电池和铅酸电池等七种储能类型在应用于削峰填谷、电网保供电和改善电压质量场景为例,并与现有的储能选型方法进行比较,体现该评价体系的创新,检验所提评价体系和选型方法的有效性。