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The research results may provide theoretical and practical references for improving the frequency stability and accuracy of HACs.In this paper, we propose a new touch-trigger probe with high precision and a large permissible measurement range. A wedge prism was used in the sensing unit to achieve 3D detection using only one optoelectronic sensor. The measurement range was expanded from ±8 µm to ±14 µm through the new optical structure. The probe has uniform stiffness and uniform sensitivity. Some experiments were performed to investigate the performance of the probe. It was found that the probe has a resolution of 10 nm and a repeatability of less than 9.1 nm. The applicability of the probe was also verified.The spin Seebeck effect (SSE) has generated interest in the thermoelectric and magnetic communities for potential high efficiency energy harvesting applications and spintronic communities as a source of pure spin current. Understanding the underlying mechanisms requires characterization of potential materials across a range of temperatures; however, for thin films, the default measurement of an applied temperature gradient (across the sample) has been shown to be compromised by the presence of thermal resistances. Here, we demonstrate a method to perform low temperature SSE measurements where, instead of monitoring the temperature gradient, the heat flux passing through the sample is measured using two calibrated heat flux sensors. This has the advantage of measuring the heat loss through the sample as well as providing a reliable method to normalize the SSE response of thin film samples. We demonstrate this method with an SiO2/Fe3O4/Pt sample where a semiconducting-insulating transition occurs at the Verwey transition, TV, of Fe3O4 and quantify the thermomagnetic response above and below TV.As part of development program for a high power co-axial transmission line component test facility, an existing traveling wave resonator based test stand is modified to improve power gain and ring return loss. The 10 dB directional coupler in the earlier test stand is replaced with a 14 dB directional coupler to couple radio frequency power with the ring. To achieve an improved isolation and return loss, the 14 dB directional coupler design is equipped with two broadside strip-lines with a tunable gap between them. Detailed design and optimization of the 14 dB directional coupler with and without the traveling wave resonator setup is performed using a high frequency simulator Computer Simulation Technology Microwave Studio. The low power test of the fabricated directional coupler is performed at several tuning positions to achieve an optimum operating frequency for the traveling wave resonator. Furthermore, after optimization, the maximum power gain of around 18 dB and minimum return loss of about -22 dB inside the ring are obtained. Finally, a preliminary study of the future 3 MW test facility is discussed.Superconducting radio frequency niobium cavities are the building blocks of modern accelerators for scientific applications. Lower surface resistance, higher fields, and high operating temperatures advance the reach of the future accelerators for scientific discovery as well as potentially enabling cost-effective industrial solutions. We describe the design and performance of an Nb3Sn coating system that converts the inner surface of niobium cavities to an Nb3Sn film. The niobium surface, heated by radiation from the niobium retort, is exposed to Sn and SnCl2 vapor during the heat cycle, which results in about 2 μm Nb3Sn film on the niobium surface. Film composition and structure as well as radio frequency properties with 1-cell R&D cavities and 5-cell practical accelerator cavities are presented.On the basis of the stress-strength model of the ball bearing with random parameters, the reliability sensitivity of the raceway strength is examined. The basic parameters are regarded as random variables subject to normal distribution. The Latin hypercube sampling method is adopted to obtain the samples, which are brought into the bearing model to obtain the corresponding maximum orthogonal shear stress. The explicit expression of shear stress was obtained by genetic algorithm-back propagation neural network fitting, and the limit-state equation is established in combination with the yield limit of bearing materials. First, this study analyzes the sensitivity of the maximum shear stress with respect to various parameters and obtains the effect of parameters on shear stress at various rotational speeds. Then, based on the stress-strength state equation, the strength reliability is obtained by using the improved first-order second-moment method, which is verified by Monte Carlo simulation. Finally, the reliability sensitivity with respect to the mean and standard variance of random variables is analyzed. This research can provide theoretical guidance for the design, production, and use of bearings.The filter-fluorescer x-ray diagnostic (FFLEX) in the Shenguang (SG) laser facility has been upgraded to infer the time-resolved behavior of hot electrons in inertial confinement fusion experiments. It significantly increases the bandwidth and anti-interference ability requirements of readout electronics. The current readout method is difficult to meet these requirements. A dedicated front-end waveform digitizer (DFWD) for the FFLEX is presented in this paper. It is very convenient to be installed in the front-end detectors of the FFLEX, and so the DFWD could be shielded as well as detectors. Conteltinib molecular weight The test results show that it works well in the front-end environment. Compared with the existing system, the DFWD can minimize the impact of radiation on signal measurement and significantly improve the accuracy of the status and time-trend diagnosis of hot electrons.We show that a simple modification to an optical table with pneumatic vibration isolation can be used to actively reduce the long term drift in the tilt of the table by nearly a factor of 1000. Without active stabilization, we measure a root-mean-square (rms) tilt variation of 270 µrad over three days. The active stabilization can be used to limit the tilt to 0.35 µrad rms over the same time period. This technique can be used to minimize drift in tilt-sensitive experiments.