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The effect of stability on reliability is a complicated problem of power system operation, and this issue has not yet been paid enough attention to the relevant research. Aiming at the problem of weak node based on voltage stability, This paper presents a method to evaluate the reliability and the weak points of optical storage and grid connected system from the angle of node voltage. Proposed the...
At present, the power flow analysis algorithm of power system has not been paid enough attention. Aiming at the problem of low accuracy and slow speed of conventional power flow algorithm, this paper proposes a new method of Improved Bisection Searching Technique(IBST) for power flow analysis, which is suitable for the active power distribution network. This method is used to find the upper and nasal...
The design of climbing tower robot is mainly consisted of two parts, including structure and control system. The mechanical structure is composed of two under actuated gripper and a linear moving body. Based on the tower environment, the structure of gripper is designed. Further analyzing the stress of climbing gripper and optimizing the structure, the climbing gripper based on under actuated gripper...
This paper proposes a novel mechanical structure for power transmission lines inspection robot. The proposed structure composed of two identical lifting arms which are connected through middle girders with two rotational joints. Symmetric mechanical structure is adopted as a whole. There are four mainly units, including motion units, open-close units, pressing units and rotating joints. Walking and...
A resonance temperature-sensing structure based on quartz tuning fork (QTF) is proposed and numerically investigated by using theoretical and numerical simulation in this paper. Reasonable selecting the quartz wafer cutting angle and Setting electrode configuration, the QTF resonator can be worked in flexural vibration mode. The numerical simulation results show that the change of the resonance frequency...
In order to realize remote monitoring and centralized management of combustible gas. A monitoring system of high performance fuel gas based on RS485 bus communication mode was presented in this paper. The system was composed of center controller and unit controller. The hardware design of unit controller and center controller was introduced, and the software design scheme of the control and communication...
As the foundation of the multi-link PenduBot control, the mathematical model should be established first. Based on the method of kinematics and dynamics, the N-link PenduBot mathematical models are established in this paper, including the nonlinear model, the linear model and the generalized model which considers the motor characteristic. The natural characteristic of the system is analyzed. By using...
Message Sequence Charts are widely used for the specification of functional requirements, including timing requirements. These requirements can be validated and used as input for the design stage, and subsequent phases. Deployment constraints are generally taken into account at the implementation stage only. These constraints may conflict and invalidate some of the functional/behavioral requirements...
To satisfy more and more complicated requirements on information recording, processing, exchange etc. in newly developed intelligent satellites, a distributed storage system is designed based on SpaceWire network in satellite platform. In this distributed storage system, a SpaceWire router unit serving as the core device of star network connects several nodes, including onboard computers, namely,...
In the control of traditional hydraulic systems, there will be large pressure fluctuations for the ordinary hydraulic cylinders in the condition of varying load. For this case, we design a four-chamber hydraulic cylinder. By using the hollow rod as another cylinder body, we make two-chamber ordinary hydraulic cylinder into four-chambers. In the control of digital fluid power systems, the number of...
There is a continuing requirement for simple, but representative methods for determining the height of maximum electron concentration of the F2-layer (symbol hmF2), both for communication and navigation. The techniques for estimating the F2-peak height hmF2 from M(3000)F2 are reviewed with particular stress put upon those in which the effects of underlying ionization are accounted for by a correction...
To study the Doppler shift phenomenon in the propagation of the short-wave signal in the ionosphere with heated F layer, the ionosphere is divided into two kinds of different parts of the normal ionosphere and the heating ionosphere. Then the expression of Doppler shift can be derived through the two part's motion. In the case of ignoring the influence of electron density with time and geomagnetic...
The split-and-project method is introduced to modeling the 3D objects with rough surfaces. With this method, the blunt-nosed cone (BNC) and delta-wing aircraft (DWA) are taken as examples to build the rough objects. The bi-static RCS of the rough objects are then simulated through Physical Optics (PO) method under different correlation length and root-mean-square (rms) height. Results indicate that...
Coastal areas worldwide are known to be especially ‘rich’ in super refractive layers and waveguides that affect microwave propagation. Radiosonde data of Xiamen and Haikou in south coast in China were chosen to analysis the rule and characteristics of the troposphere duct in this paper. Based on the historical data, improved learning vector quantization neural network method (LVQ) and improved Radial...
Based on the Weaver's model and Neumann ocean waves spectrum, the three-dimensional space of the three-dimensional random waves and three-dimensional model of the magnetic field generated by water movement are simulated in this paper. This paper provides a weak magnetic field reference model for the magnetic detection of long distance underwater magnetic object.
RCS of a waving target with uniform rough distribution is calculated by Physical Optics (PO) Method in Ka and Terahertz Bands respectively. So is another assembly consisting of a cylinder and a little cubic. The results show that the RCS of the two targets are different both in amplitude and symmetry. For a certain target, the results demonstrate that EM wave in terahertz band has a higher resolution...
The prediction accuracy of an indoor ray tracing model is obviously affected by the accuracy of environment information. Thus, a modeling approach for the choice of the environment information is presented in this paper. To provide good prediction accuracy using an indoor ray tracing model, the present study divides the indoor environment modeling in two ways: geometric modeling and electrical parameter...
A mechanism of communication through plasma sheaths which surround vehicles traveling at hypersonic velocities is introduced. The idea is to use nonlinear effects to make the plasma sheath appear transparent.
The propagation properties of THz electromagnetic wave (EM wave) in a magnetized plasma which is inhomogeneous in both collision frequency and electron density are analyzed theoretically in this study. By utilizing the scattering matrix method (SMM) method, the effects of Electron density, collision frequency, the thickness of the plasma and the electron temperature on the absorption coefficient are...
Some studies of the influences from typical scene (target, rough surface) parameters on the target and rough surface composite electromagnetic scattering characteristics are carrying out. The target and rough surface with specific type and spectrum cases are considered. The composite scattering integral equations are built. The numerical hybrid strategies, such as the Propagation-Inside-Layer-Expansion...
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