摘要：The RF coupler is a key component for an accelerating structure which is the most important component for a linac. In order to feed microwave power into the accelerating cavities effectively, the coupler has to be well matched with the feeding waveguide. In this paper, an electron linac coupler was designed, constructed and tested. A numerical simulation method based on the Kyhl＇s method was employed to search for the optimal dimensions of the coupler. The frequency and the coupling coefficient as a function of the coupler dimensions were also calculated. The results fitted the Kyhl＇s method simulation results well and gave tolerances of the coupler. The coupler was brazed to the accelerating cavities and it was cold-tested and hot-tested. The experimental results were consistent with the numerical simulation results.

摘要：An updated main coupler has been designed for the superconducting accelerator of Free Electron Laser （FEL） project under construction in Peking University. A capacitive structure is chosen for the main coupler. Numerical investigation using CST Microwave Studio demonstrates the cold window part. The other nonstandard structures such as holding rods and antenna are also optimized. The coupler uses a 95% purity Al2O3 ceramic cold window. The VSWR （Vottage Standing Wave Ratio） is 1.02 at 1.3 GHz and the frequency bandwidth is 45 MHz with VSWR〈I.1. The electric field intensity is 8.5× 10-2 kV/mm around the window with 20 kW Continuous Wave （CW） transmitted power. The Qext is designed variable from 5× 10^8 to 1×10^7.

摘要：We propose a design and optimization for directional coupling in terahertz hybrid-cladding hollow waveguide. It is composed of two square hollow waveguides which touch each other and are surrounded by a metallic layer. By employing the finite element method, the coupling performance and loss property are numerically investigated. Numerical results indi- cate that this directional coupler with hybrid-cladding can realize ultra-narrow-band coupling; it provides a low confinement loss performance： the confinement loss can reach as low as 6.27 × 10-5 cm- 1. Moreover, the further analyses of configura- tion and performance show that confinement loss and frequency range shift for the low-confinement-loss frequency regime can be realized and optimized by appropriately tuning the thickness values of the metallic and dielectric layer. In addition, through the further analysis of coupling performance, the possibilities of realizing ultra-narrow-band couplings in different frequency ranges are demonstrated. It is a powerful candidate for high precision optical fiber sensing, and communication in terahertz splitting fields.

摘要：A new approach to the design of the optical fiber direction coupler by using neural network is proposed. To train the artificial neural network,the coupling length is defined as the input sample, and the coupling ratio is defined as the output sample. Compared with the numerical value calculation of the theoretical formula, the error of the neural network model output is 1% ***, through the model, to design a broadband or a single wavelength optical fiber direction coupler becomes easy. The method is proved to be reliable, accurate and time saving. So it is promising in the field of both investigation and application.

摘要：A 2 × 2 optical waveguide coupler at 850 nm based on the multimode interference （MMI） structure with the polysilsesquioxanes liquid series （PSQ-Ls） polymer material and the imprint technique is presented. The influence of the structural parameters, such as the single mode condition, the waveguide spacing of input/output ports, and the width and length of the multimode waveguide, on the optical splitting performance including the excess loss and the uniformity is simulated by the beam propagation method. By inserting a taper section of isosceles trapezoid between the single mode and multimode waveguides, the optimized structural parameters for low excess loss and high uniformity are obtained with the excess loss of -0.040 dB and the uniformity of-0.007 dB. The effect of the structure deviations induced during the imprint process on the optical splitting performance at different residual layer thicknesses is also investigated. The analysis results provide useful instructions for the waveguide device fabrication.

摘要：In order to overcome the main drawbacks of coaxial, waveguide, and stripline couplers, the analysis and the design of a compact coaxial-to-microstrip directional coupler convenient for power and antenna control application, are presented using the method of moments (MoM) in two dimensions. This technique is adapted to study the complex configuration of the line’s system, which does not have a simple analytical solution. The modeling of this structure consists in analyzing the primary inductive and capacitive matrices ([L] and [C]). When these matrices are determined, it is possible to calculate the inductive and capacitive coupling coefficients (kL and kC) and estimate the resulting scattering parameters of the coupler using an adapted numerical model. The coupler can be integrated into a printed circuit board (PCB) and operates over 17 to 35 dB coupling coefficients and is always compensated. The compensation is achieved by the proper displacement of a tuning ground plane with respect to the edge of the PCB from 0.1 to 3.3 mm. As an application, we present the design of a compact coupler with 7.5 × 4.8 × 25.8 mm of size and having approximately 20 dB of coupling coefficient at 2 GHz and a minimum directivity of 23.3 dB in the frequency range [0.1 - 4] GHz. In order to check our numerical calculations by the MoM we made simulations in 3D by using CST MICROWAVE STUDIO software for the same geometrical and physical parameters of our designed coupler. The results obtained by the two numerical models (MoM and CST) show a good agreement of the frequency responses of the coaxial-to-microstrip directional coupler. The studied structure represents a great improvement for high power measurement systems, since it has broad-band, good directivity, and can be easily designed and fabricated.

摘要：A new special coupler with a kind of bowl-shaped ceramic window for a proton linear accelerator named the Chinese Accelerator Driven System （C-ADS） at the Institute of Modern Physics （IMP） has been simulated and constructed and a continuous wave （CW） beam commissioning through a four-meter long radio frequency quadruple （RFQ） was completed by the end of July 2014. In the experiments of conditioning and beam, some problems were promoted gradually such as sparking and thermal issues. Finally, two new couplers were passed with almost 110 kW CW power and 120 kW pulsed mode, respectively. The 10 mA intensity beam experiments have now been completed, and the couplers during the operation had no thermal or electro-magnetic problems. The detailed design and results are presented in the paper.

摘要：Rolling stock connection systems are key to running longer and heavier trains as they provide both the connections of vehicles and the damping,providing the longitudinal suspension of the *** paper focuses on the evolution of both connection and stiffness damping *** is on freight rolling stock,but passenger draw gears are also *** was found that connection systems have evolved from the buff and chain system used in the pioneer railways of the 1800s to the modern auto-coupler connection systems that are in-service worldwide *** versions of the buff and chain coupling are,however,still in use in the EU,UK,South America and India.A wide range of auto-coupler systems are currently utilised,but the AAR coupler(Janney coupler)remains the most popular.A further variation that persists is the SA3 coupler(improved Wilson coupler)which is an alternative auto-coupler design used mainly throughout the former Soviet *** the review to auto-coupler systems allowed the paper to focus on draft gears which revealed polymer,polymer-friction,steel spring-friction,hydraulic draft gears and sliding sill cushioning *** with the single compressive draft gear units balanced and floating plate configurations are also *** draft gear acceptance standards are presented along with modelling that was included to aid in presentation of the functional characteristics of draft gears.

摘要：分析了汽车涂装车间厂房通风系统的整体设计方案及控制方法。采用西门子S7-300PLC、PROFINET工业以太网、SINAMICS G120变频器、组态软件Win CC、远程输入输出模块ET200S及PN/PN coupler构建控制系统,对采集的数据进行集中管理和实时监控。在实际运行过程中取得了良好效果,满足了设计要求。