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101.
非线性脉冲时滞抛物型偏微分方程的强迫振动性 总被引:8,自引:0,他引:8
考虑一类具强迫项的非线性脉冲时滞抛物型偏微分方程,利用脉冲时滞微分不等式,获得了该类方程的解强迫振动的若干充分判据。 相似文献
102.
Some applications of impulse control in mathematical finance 总被引:5,自引:0,他引:5
Ralf Korn 《Mathematical Methods of Operations Research》1999,50(3):493-518
103.
一类与半鞅有关的推广型脉冲控制(I) 总被引:2,自引:0,他引:2
本篇首次将关于半鞅的随机微分方程的解过程引入平稳型脉冲控制的状态结构,建立了一种新的模型,从而实质性地推广了此前的各类平稳型脉冲随机控制模型.本篇通过新的分析手法证明了与新模型相关的变分方程解的存在性,这种新方法比以前类似问题的分析方法更直接、更明快. 相似文献
104.
A compound expansion-chamber muffler, which consists of a sound absorbing chamber and a switch valve, the chamber integrating structural features of impedance muffler and micropunch plate muffler, is proposed to diminish impulse exhaust noise of pneumatic friction clutch and pneumatic friction brake (PFC/B) in mechanical presses. The structure decreases the impulse exhaust noise of PFC/B over 30 dB(A). A one-dimensional flow model is applied to study the aerodynamic characteristics of compound exhaust process of the single acting cylinder and muffler because the exhaust time is a critical factor for application of muffler in PFC/B. The volume of sound absorbing chamber is found to be an important design parameter to minimize the exhaust resistance of pneumatic cylinder. Experiments are also conducted to validate analytical results. Then the effects of diameter of exhaust ducts and volume of muffler on the exhaust time are discussed in detail. The proposed one-dimensional computational method, which considers the coupling of air-flow field and sound field, gives satisfactory results for the preliminary design of an expansion-chamber muffler. This method has been applied to an existing model HKM3-40MN to reduce its impulse noise. 相似文献
105.
The paper analyzes dollarization in the Turkish economy given the evidence on dedollarization signals. On conducting a Vector Autoregression (VAR) model, the empirical evidence suggests that dollarization has mostly been shaped by macroeconomic imbalances as measured by exchange rate depreciation volatility, inflation volatility and expectations. Furthermore, the generalized impulse response function (IRF) analysis, in addition to the analysis of variance decomposition (VDC) gives support to the notion that dollarization seems to sustain its persistent nature, thus hysteresis still prevails. Hence, unfavorable macroeconomic conditions apparently contribute to dollarization while dollarization itself contains inertia. Furthermore, dedollarization that presumably started after 2001 has lost headway after May 2006. Thus, it seems too early to conclude that dollarization changed its route to dedollarization. 相似文献
106.
107.
I.lntroductionTheequaltraveltimelayermodelisausefulmodelinseismicinverseproblemforverticallylayeredmedial1].Goupilaudinverseformulacanbedirectlyusedtoinvertlayersreflectioncoefficientsfromtheimpul8eresponsel2l.WareandAKishowedthatthereisacloseanalogybetweentheGoupilaudsolutionandthecontinuousMarchenko'ssolution[3].BerrymanandGreelleshowedthatthereekistsaonetoonecorrespondingbetweentheGoupilaudsolutionandthediscretedcontinuousinverseproblem[4].Recentyears,somenewmethodssuchasD-CmethodandC-… 相似文献
108.
B. Protas 《Journal of Fluids and Structures》2011,27(8):1455-1460
This note addresses the question why the “impulse formula”, often employed to compute hydrodynamic forces in vortex-dominated time-dependent flows, is not applicable to steady flows in unbounded domains. By analyzing the asymptotic structure of steady and unsteady flow solutions in unbounded domains, it is demonstrated that one assumption made in the derivation of the impulse formula is in fact not satisfied in the steady case. This result also highlights the special character of steady flows in unbounded domains. 相似文献
109.
Zhonghai Guo Xiaoliang Zhou Weigao Ge 《Journal of Mathematical Analysis and Applications》2011,381(1):187-201
In this paper, by arithmetic-geometric mean inequality and Riccati transformation, interval oscillation criteria are established for second-order forced impulsive differential equation with mixed nonlinearities of the form
110.
Optimal dividend and capital injection problem in the dual model with proportional and fixed transaction costs 总被引:1,自引:0,他引:1
In this paper we consider the dividend payments and capital injections control problem in a dual risk model. Such a model might be appropriate for a company that specializes in inventions and discoveries, which pays costs continuously and has occasional profits. The objective is to maximize the expected present value of the dividends minus the discounted costs of capital injections. This paper can be considered as an extension of Yao et al. (2010), we include fixed transaction costs incurred by capital injections in this paper. This leads to an impulse control problem. Using the techniques of quasi-variational inequalities (QVI), this optimal control problem is solved. Numerical solutions are provided to illustrate the idea and methodologies, and some interesting economic insights are included. 相似文献