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A flexible tactile sensor was proposed to measure the three-dimensional forces. The sensor consisted of a bump structure, top and bottom electrodes, a piezoelectric sensitive layer and a substrate layer. The top and the bottom electrodes were prepared by lift-off process. When a three-dimensional force was applied, the bottom four electrodes under the bump structure would collect different charge signals, which can be detected by the different electric current variations. In the experiments, when the forces range from 0 to 10N with different angles were applied to the bump structure, the sensor can measure forces with a best non-linearity of 1.89%. This proposed tactile sensor could be used in the intelligent robotics to measure multi-dimensional force.

An improved peninsula-island structured pressure sensor was presented with the novel dry-wet combination etching process. There were four pairs of segmented mass blocks attaching on the back of the diaphragm. Each segmented mass block was composed of a peninsula structure and an island structure with anisotropic-etching-induced sidewalls. The improved structure not only inherited the stress concentration feature of low strain energy dissipation but also improved the comprehensive ability of the sensor chip, including low fabrication cost, high etching uniformity, good temperature performance and low residual stress in the diaphragm. Also, the fabrication method combining DRIE (Deep Reactive Ion Etching) and anisotropic wet etching was verified by the simulation based on the Sentaurus 2013. The fabrication error caused by anisotropic wet etching was analyzed. Compared with the flat film of the same size, the proposed structure can increase the sensitivity by 225%, reduce the nonlinearity by 80.3%, and increase resonance frequency by 11%. In addition, the sensor structure can also be applied to pressure sensors with different working range, which will be helpful to design the pressure sensors with high efficiency and accuracy.

Lumped element model (LEM) for resonant chemical sensors based on the capacitive micromachined ultrasonic transducers (CMUTs) was developed and analyzed with electrical characterization. The CMUTs chip were functionalized with the electrospinning technology. Two Butterworth Van-Dyke (BvD) models for functionalized CMUTs were proposed and analyzed with different DC voltages. Considering the electrical phase with parasitic capacitance, the modified BvD model can be used to illustrate more comprehensive features for both mechanical impedance and phase properties. The parallel capacitance was measured accurately using an impedance analyzer, and the quality factor was calculated based on the proposed model under different DC voltages. These models will provide important theoretical basis for CMUTs-based chemical sensors to further electrical analysis and oscillator design.

A high-accuracy differential resonant pressure sensor with two similar resonators is proposed using the linear fitting method to guarantee its output linearity without polynomial compensation. Results reveal that the nonlinearity of the differential resonant pressure sensor is largely dependent on the tensile/compressive sensor pressure–stress ratio c when two similar resonators are used separately as compressive and tensile elements. Nonlinearity decreases sharply with an appropriate ratio c. A theoretical model is proposed to obtain minimal nonlinearity and shows satisfactory agreement with the simulation results. The impact factors of ratio c are analyzed to facilitate adjustments with the designed value. Moreover, micromachining methods are used to fabricate sensing chips. Experiment results show that the nonlinearity and measurement sensitivity of the proposed differential resonant pressure sensor are ±0.02% FS and 35.5 Hz kPa−1 with the linear fitting method in a pressure range of 0–200 kPaA and temperature range of −40 °C to +40 °C. The differential linear fitting method largely decreases compensation complexity without polynomial fitting for high-precision pressure measurement.

Simulation mathematical model of maneuverability such as zig-zag and turning circle test under different rudder and speed is built and the rudder rotary response effect on ship maneuverability parameters is analyzed extensively. In the paper, MMG (maneuvering model group) model is adopted to set up the 3 degrees of freedom governing equations of ships, in which the rudder rotary response is approximated by the assumption of uniform rotary speed. A sea-going vessel of 10 thousand deadweight tonnages is selected as the numerical simulation target to investigate the rudder rotary response effect on ship maneuverability parameters, such as the zig-zag and turning circle test. Some meaningful conclusions are concluded through comparative analysis, the conclusions indicate that rudder rotary response has remarkable effect on ship maneuverability, and it is a significant factor which needs to be taken into consideration for actual ships.

A micro electromechanical systems (MEMS) resonant sensing chip with microcantilever has been developed to measure gas pressure by immersing it in gaseous environment. The microcantilever was designed to sense surrounding gas molecules loading, owing to the gas density sensitive to the pressure, then the resonant frequency shifts of sensing chip were induced under different pressures. Especially, the sensing chip featuring no diaphragm realized embedded package and installation for the immersive measurement. The resonance response of the sensing chip for target pressure was theoretically analyzed and simulated, and a packaged pressure sensor with the proposed sensing chip was tested under flexural and torsional modes of the microcantilever. The experimental results proved that the proposed sensor had preferable measuring performance under the torsional mode with the RSS (root sum square) accuracy of 0.21%FS in the working range of 10–560 kPa. The temperature compensation was presented to alleviate the temperature disturbance for the sensor, and the maximum deviation of the frequency was 59 ppm over the full pressure and the temperature range of 26–55 ℃. The proposed sensing chip is potentially a better choice for pressure sensors with measurement demand for immersive gas pressure.

The differential cross sections of the discrete gamma rays at 55® produced in the inelastic interaction of 14.2 MeV neutron with Fe, Ni, Cu, Pb and Bi have been measured using a heavy complete shielded Ge(Li) detector. TOF technique is used with the zero time picked by associated alpha particle in T(d,n)4He reaction. Tens of discrete gamma rays for each sample are identified and analysed. The energy level schemes and their transitions for various residual nuclei have been deduced. For determining the production cross sections, the correction factors of incident neutron attenuation and multiscattering in sample are calculated by Monte-Carlo method. The lowest limit of cross section measured in this experiment is about 0.2 mb/sr. The reliability of data have been checked in comparison with estimated total inelastic secttering cross sections.