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991.
992.
Linus Kaisajuntti 《Applied Mathematical Finance》2013,20(4):327-358
Abstract This article develops and tests an n-dimensional Markov-functional interest rate model in the terminal measure based on parametric functional forms of exponential type. The parametric functional forms enable analytical expressions for forward discount bonds and forward LIBORs at all times and allows for calibration of the model to caplet prices given by a displaced diffusion Black model. The analytical expressions of the model provide a theoretical tool for understanding the structure of standard Markov-functional models (MFMs) as well as comparisons with the LIBOR market model (LMM). In particular, it is shown that for ‘typical’ market data the model is close enough to the LMM to be able to calibrate using the LMM calibration set-up and machinery. This provides further information about the similarities (as well as some of the differences) between MFM and LMM. The parametric n-dimensional MFM may be used for products that require high-dimensional models for appropriate pricing and risk management. When compared with an n-factor LMM, it has the virtue of being (much) faster for certain types of products. 相似文献
993.
S. Sacone 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(3):275-293
In this article the operational planning of seaport container terminals is considered by defining a suitable integrated framework in which simulation and optimization interact. The proposed tool is a simulation environment (implemented by using the Arena software) representing the dynamics of a container terminal. When the system faces some particular conditions (critical events), an optimization procedure integrated in the simulation tool is called. This means that the simulation is paused, an optimization problem is solved and the relative solution is an input for the simulation environment where some system parameters are modified (generally, the handling rates of some resources are changed). For this reason, in the present article we consider two modelling and planning levels about container terminals. The simulation framework, based on an appropriate discrete-event model, represents the dynamic behaviour of the terminal, thus it needs to be quite detailed and it is used as an operational planning tool. On the other hand, the optimization approach is devised in order to define some system parameters such as the resource handling rates; in this sense, it can be considered as a tool for tactical planning. The optimization procedure is based on an aggregate representation of the terminal where the dynamics is modelled by means of discrete-time equations. 相似文献
994.
在狭小空间或是恶劣环境下进行数据采集,传统的数据采集设备占用空间大、传输速率慢,不方便携带。通过分析这些缺点,设计了一种基于WiFi无线网络技术的便携式的无线数据采集控制系统。整个系统包括数据采集单元、数据传输单元和数据控制单元三大部分。该数据采集控制系统能够在WiFi网络覆盖区域内,以手持Android小型终端为控制终端,以无线网络为传输通道,实时控制数据采集卡,并读取采集数据,即时数据可帮助用户更加可靠的分析实际情况,具有实际应用价值。 相似文献
995.
根据永磁超环面电机特殊的转子结构,建立了该电机的电磁参数方程,并推导了含行星轮转子位置信息的时变数学模型,应用状态空间法分析了该电机的周期波动特性。结合超环面电机的时变参数,完成了对其PI控制器的参数整定。结合行星轮自转引起的参数摄动,将闭环系统反馈得到转子位置信息引入到终端滑模控制器中,使控制器参数跟踪超环面电机的时变参数。将终端滑模控制与PI控制的仿真结果对比分析,结果表明:该控制策略有效地削弱了永磁超环面电机输出性能上的周期波动,并且具有良好的响应速度、抗干扰性和鲁棒性。 相似文献
996.
针对欠驱动自治水下机器人(autonomous underwater vehicle,AUV)在外部干扰和系统内部扰动下深度难以控制的问题,提出基于非线性干扰观测器(nonlinear disturbance observer,NDO)的自适应终端滑模控制方法。首先建立欠驱动AUV在垂直面上的状态方程并对其简化,其次根据简化后的系统状态方程构建NDO对外部干扰进行观测,再结合反步法设计出自适应终端滑模控制器;最后通过李雅普诺夫稳定性理论证明控制系统的稳定性。结果表明:欠驱动AUV最大跟踪误差为0.137 5 m,峰值时间为2.1 s,证明了所设计的控制器能够实现深度控制,降低抖振,具有较强的鲁棒性。 相似文献
997.
Xiaojin Lin 《中国科学技术大学学报》2022,52(8):3-1-3-5
We provide an intrinsic algebraic definition of the intersection complex for a variety. 相似文献
998.
A series of copper(II) complexes containing 6‐methyl‐2‐oxo‐1,2‐dihydroquinoline‐3‐carboxaldehyde‐derived Schiff bases have been synthesized and characterised using various analytical and spectroscopic techniques. X‐ray crystallographic analysis confirmed the true coordinating nature of ligands with copper ion. The ligands exhibited ONS tridentate neutral and monobasic coordination. The spectroscopic results evidenced the interaction of the ligands and their copper(II) complexes with nucleic acid/serum albumin. Further, the complexes showed significant activity against human skin cancer cell line (A431) and less toxicity against human keratinocyte cell line (HaCaT). Acridine orange/propidium iodide dual staining studies indicated that the major cause of A431 cell death was through necrosis. By comparing the biological activity of all the ligands, Cu(II) complexes and standard (cisplatin), complex [Cu(H‐6MOQtsc‐Ph)(H2O)]?NO3 ( 4 ) exhibited better activity than others, the activity being arranged as follows: 4 > 1 > cisplatin > 3 > 2 . 相似文献
999.
Xueling Mo Bin Chen Guozhu Zhang 《Angewandte Chemie (International ed. in English)》2020,59(33):13998-14002
An asymmetric copper‐catalyzed Sonogashira type coupling between alkynes and α‐bromoamides has been developed. This method represents a facile approach to synthetically useful β, γ‐alkynyl amides from two readily available starting materials in a highly enantioselective manner. A Bisoxazoline diphenylanaline (BOPA) serves as the effective chiral ligand. Preliminary mechanistic studies support the formation of alkyl radical species . 相似文献
1000.
Xiangdong Xue Mayur K. PatelMaïwenn Kersaudy-Kerhoas Marc P.Y. DesmulliezChris Bailey David Topham 《Applied Mathematical Modelling》2012,36(2):743-755
The behaviour of a fluid, which may contain particle suspensions, flowing in micro-dimensional channels is governed by both viscous and surface tension forces as well as high shear rates and geometric effects such as bifurcations, constriction, and high surface-to-volume ratio. This paper discusses some of the key design factors affecting fluid behaviour in micro-engineered products containing a main channel, constriction and side channel bifurcations. Differences in fluid behaviour at the macro and micro-scales are discussed. The dynamic bulk fluid behaviour is characterised in terms of: (i) fluid properties, (ii) governing physics and (iii) microchannel geometric features.At this stage of the analysis the fluids are assumed to be Newtonian and single phase, where any particle suspension is represented through a bulk density and viscosity. Based on these assumptions Computational Fluid Dynamics (CFD) is used to investigate the effect of both product inlet and outlet boundary conditions on the bulk flow behaviour. Discussions are provided on how these boundary conditions can affect particle separation efficiency. In particular, the so called pull-design whereby the fluid is pulled out of the device at the outlet, is shown to offer better performance compared to the mode of operation where the fluid is pushed into the device at the inlet. It is also observed that increasing the pressure at the outlet of the main channel can achieve a balanced flow rate ratio which leads to a uniform separation performance among all bifurcations. 相似文献