Model predictive control of bidirectional isolated DC–DC converter for energy conversion system

Model predictive control (MPC) is a powerful and emerging control algorithm in the field of power converters and energy conversion systems. This paper proposes a model predictive algorithm to control the power flow between the high-voltage and low-voltage DC buses of a bidirectional isolated full-bridge DC–DC converter. The predictive control algorithm utilises the discrete nature of the power converters and predicts the future nature of the system, which are compared with the references to calculate the cost function. The switching state that minimises the cost function is selected for firing the converter in the next sampling time period. The proposed MPC bidirectional DC–DC converter is simulated with MATLAB/Simulink and further verified with a 2.5 kW experimental configuration. Both the simulation and experimental results confirm that the proposed MPC algorithm of the DC–DC converter reduces reactive power by avoiding the phase shift between primary and secondary sides of the high-frequency transformer and allow power transfer with unity power factor. Finally, an efficiency comparison is performed between the MPC and dual-phase-shift-based pulse-width modulation controlled DC–DC converter which ensures the effectiveness of the MPC controller.     

Pro Tools光纤网络系统设计分析

分析了Pro Tools光纤网络系统的构成、特点,对系统工作流程进行了简要说明,特别强调了项目中重点考虑的几点问题,最后从网络技术核心、按需要组织的应用流程等方面设计了此网络系统。     

城市统一信息交换平台的特点

针对信息化建设中出现的"信息孤岛"和重复投资、盲目建设、信息资源分散、系统应用关联性差等问题,提出了城市信息化统一信息交换平台的解决方案.介绍了平台框架和其具有的统一用户、统一认证、统一接口、统一支付、统一资源、统一管理、统一交换、统一接入等特点.     

Opto-mechatronic configurations to maximize dynamic range and optimize resolution of optical instruments

We developed a new mechanical configuration which combines various optical techniques to maximize dynamic range and to optimize resolution in optical instruments. We assessed various optical configurations by looking at such variables as electronic signal processing and mechanical construction. Previous configurations developed over the last 10 years are discussed. In our new configuration, we adopted and integrated devices such as a microscopic, an interferometer, an electronic speckle pattern interferometer, and a photon tunneling microscope. We examined the impact of our new configuration on future opto-mechatronic systems design. Our new configuration can be an effective and versatile optical metrology tool for enhancing the performance of MEMS and NEMS devices.     

Irreducibility and Compositeness in q-Deformed Harmonic Oscillator Algebras

A study of the reducibility of the Fock space representation of the q-deformed harmonic oscillator algebra for real and root of unity values of the deformation parameter is carried out by using the properties of the Gauss polynomials. When the deformation parameter is a root of unity, an interesting result comes out in the form of a reducibility scheme for the space representation which is based on the classification of the primitive or nonprimitive character of the deformation parameter. An application is carried out for a q-deformed harmonic oscillator Hamiltonian, to which the reducibility scheme is explicitly applied.On leave from     

有幺单Γ－环类所确定的上根

结合环根论中由具有单位元的单环类所确定的上根就是Ｂｒｏｗｎ－ＭｃＣｏｙ根．本文指出在Γ－环中，鉴于Γ－环单位元的复杂性质使得有幺单Γ－环类确定的上根演变成８个，进而研究了这些根之间及这些根与Γ－环其它根之间的大小关系．     

Noncommutative Cohomology and Electromagnetism on $$\mathbb{C}$$ q [SL2] at Roots of Unity

We compute the noncommutative de Rham cohomology for the finite dimensional q-deformed coordinate ring _q [SL₂] at odd roots of unity and with its standard four-dimensional differential structure. We find that H ⁱ is highly nontrivial compared to case of generic q and has as many modes 1 : 4 : 6 : 4 : 1 as the dimension of the exterior algebra. We solve the spin-0 and Maxwell theory on _q [SL₂], including a complete picture of the self-dual and anti-self dual solutions and of Lorentz and temporal gauge fixing. The system behaves in fact like a noncompact space with self-propagating modes (i.e., in the absence of sources). We also solve with examples of electric and magnetic sources including the biinvariant element H ¹ which we find can be viewed as a source in the local (Minkowski) time-direction (i.e. a uniform electric charge density).     

遵义电视台4频道数字硬盘播出系统

简要介绍了遵义电视台4频道数字硬盘播出系统设计，该系统以美国AVID MSS 8000视频服务器为核心。采用国内硬盘播出领域占有量最高的北大方正无忧播控软件。配置被国内省级电视台广泛使用的周边设备。实现4个频道的播出。此项目的成功意味着在国际上享有盛誉的AVID MSS 8000视频服务器进入了贵州省地市级电视台应用领域。