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In order to shorten the time it takes for the manipulator components to reach the preset position and avoid the behavior state of excessively increasing the gripping angle, an automatic control system for the gripping angle of the manipulator based on machine vision is designed. According to the motion state of the mechanical components of the gripper, the connection sensitivity of the angular position sensor is controlled, and then the tension and pressure control structure is used to complete the on-demand adjustment of the clamping force action form and realize the construction of the application platform environment of the hardware structure of the automatic control system. On this basis, by grabbing the necessary manipulator operation image, following the principle of machine vision, completing the preprocessing, and then combining the kinematic functions to perform the force control switching operation and realizing the gripping force control based on machine vision, and completing the design and application of the automatic control system for the gripping angle of the manipulator. The experimental results show that when the motor driving speed is equal to 2000 PPS,4000 PPS, and 6000 PPS, the consumption time required for the manipulator components to reach the preset position will not exceed 9.5s. Compared with the double closed-loop control system, it is more in line with the application requirements of effectively controlling the behavior of the clamping angle.

This paper takes the three - way redundant drive parallel machine tool as research object, designs a magneto-rheological damper with displacement amplification function and simulates the magnetic circuit saturation of the damper by the Ansys workbench finite element analysis software, so that the output of the damper comes to optimization. The research results show that the magnetic field distribution is more reasonable, and the mechanical properties of the damper are improved. The optimization method is feasible and effective.

The quality of Shanxi aged vinegar (SAV), a famous Chinese vinegar, was improved during its special long-time ageing. SAV samples of different ageing time were analyzed by composition analysis, rheometer, and principal component analysis (PCA). Three main quality indicators of SAV, namely total acidity, soluble solids content and R ratio, and most of composition, including glucose, acetic acid, lactic acid and total polyphenols increased when ageing process prolonged. Newton function and Power law model were fitted to rheological data to investigate the rheological characters: shear viscosity, consistency coefficients and flow behavior index (n). PCA showed the viscosity of SAV had positive relationship with ageing time as well as all composition parameters. Quality including main quality indicators, composition and rheological characters was significantly differenct (p < 0.05) among the SAV in different phases. Thus, the rheological method was a very useful tool to classify the quality of SAV.

In the study, the numerical simulations of gas-assisted extrusion molding (GAEM) of double-lumen micro-catheter (DLMC) with asymmetric structure were performed via the finite element software package Polyflow. At the same time, the numerical results of traditional extrusion were also obtained. The numerical extrusion profile, deformation, and the die swell ratios of DLMC based on the traditional and GAEM were all gotten, and compared with each other. In addition, to analyze the effect of gas-assisted on the elimination of the extrusion problems, the physical field distributions of melt for both extrusions were also compared and analyzed. Numerical results show that the obvious die swell and large extrusion deformation of DLMC generated by the traditional method were all eliminated by using the GAEM.

The numerical simulations of the gas-assisted extrusion (GAE) of double-lumen plastic catheter (DLPC) were performed by using the software Polyflow. The extruded profiles, swell ratios, flow velocities, pressures, stresses of melt based on gas-assisted method were gotten and compared with those of traditional method. Results show that the gas-assisted method can well eliminate the extrusion swell and deformation phenomena of DLPC. The reasons are that, by means of gas-assisted method, the radial velocity of melt is zero, axial velocity distributions are uniform, pressure and stresses are greatly less than the traditional extrusion. Therefore, the gas-assisted method has great value used in the extrusion forming of DLPC.

In this work, the gas-assisted extrusion of four-lumen micro-catheter (FLMC) was numerically studied by computed fluid dynamics (CFD) software software Polyflow. The extrudate profiles and die swell ratios of FLMC for the gas-assisted extrusion are gotten, and compared with those of the traditional extrusion. Results show that the die swell of FLMC is eliminated by the gas-assisted extrusion. To analyze the effects of gas-assisted on the elimination of die swell, the flow velocities, pressure, shear stress, and the first normal stress difference distributions of melt were obtained for both extrusions. Results show that compared with the results of traditional extrusion, the radial velocities, pressure, shear stress and the first normal stress difference of FLMC for the gas-assisted extrusion are very little, and the axial flow velocity of melt is uniform, which can reduce the elastic energy storage and finally eliminate the die swell problem.

To ascertain the mechanism of gas-assisted extrusion (GAE) deformation for the plastic micro-pipe (PMP), the transient simulation was done. The geometric model based on three phase fluids and finite element mesh were established. To get the converge solutions, the Crank-Nicolson integration, the interpolation method of elastic-viscous split-stress finite element method combined with streamline-upwind scheme were used. At the reasonable boundary and material conditions, the GAE forming of PMP for different gases flow rates were numerically studied. Moreover, the extrusion profiles of PMP under different transient times were also obtained. To explain the reason of surface deformation for the GAE forming of PMP, the radial and axial velocity, and stress difference of melt under larger gases flow rates at different transient times were all obtained. The transient numerical results can better interpret the mechanism of surface deformation of PMP.

In this study, the effects of interfaces heat fluxes on the rheological and flow behaviors of melt in the gas-assisted extrusion of plastic micro-tube were numerically investigated. In the numerical studies, the heat transfer effect at the interfaces between the annual melt and two layers of assisted gases were considered. Under four different heat transfer coefficients, the radial and axial velocities, pressure, temperature, and viscosity distributions along the axial direction of die were obtained. Numerical results show that, in the gas-assisted extrusion of plastic micro-tube, with the increase of interfaces heat fluxes (heat transfer coefficient), the radial velocity, axial velocity, and temperature distributions of melt gradually increases, but the pressure, viscosity of melt gradually decreases. At the same time, the larger interfaces heat fluxes will result in the better flowability of melt in the gas-assisted extrusion of plastic micro-tube.

Magneto-rheological elastomer is a new type of magneto-rheological material characterized by controllable reversibility of rheological properties and very short response time. Moreover, the stability is good and the structure design is simple, so it has broad application prospects in the fields of intelligent vibration reduction and noise reduction, electromagnetic sensors and active control. The research status of magneto-rheological elastomers at home and abroad is introduced systematically, including the mechanical model of magneto-rheological elastomers, magneto-mechanical properties, influencing factors and engineering applications, and several problems that should be further studied in the future are proposed.

The effects of traction velocity on gas-assisted extrusion (GAE) and traditional extrusion (TE) of plastic micro-tubes (PMTs) were numerically studied in this paper. Under same 3D geometric model, boundary conditions setting and constitutive parameters, the extrudate profile change and swell ratios of GAE and TE were all obtained. The radial and axial flow velocities, shear stress and first normal stress difference distributions of melt under different traction velocities were also gotten and compared. Results show that with the increase of traction velocity, the swell ratio increases first and then decreases. When the traction velocity is less than the axial velocity of melt, the radial velocity of melt outside of die increases, which demonstrates the generation of radial swell. When traction velocity is larger than that of the melt, the negative radial velocity of melt generates, which demonstrates the generation of shrinkage phenomenon. In addition, the changes of shear stress values and first normal stress difference values are not large, and the sudden increase of stresses always generates at the outlet die for the TE. However, the stresses of melt are well removed at the outlet of die, which demonstrates that extrudate swell and melt fracture problems are well eliminated by the GAE during the extruded PMTs dragged by traction velocity.

The effect of inner assisted gas length on the gas-assisted extrusion forming of plastic micro-tube was numerically studied in this paper. The 2D geometric models with different lengths of inner assisted gas were established. Under the same boundary conditions and material parameters, the profile changes of extruded plastic micro-tubes were obtained. To ascertain the reasons of profile changes induced by different lengths of inner assisted gas, the radial and axial flow velocities, shear stress and the first normal stress differences of melt were all obtained. Numerical results show that the diameter swell or shrinkage phenomenon occurs when the inner assisted gas length mismatches the outer assisted gas length. The deformations are generated by the unbalance axial flow velocity of melt induced by the mismatch of two assisted gases lengths, especially at the outlet of assisted gases. At the same time, the shear stress focus and first normal stress difference focus of melt are also existed at the outlet of assisted gases. In practice, the lengths of two assisted gases should be equal in the gas-assisted extrusion of plastic micro-tube.

In this paper, the effect of viscous flow activation energy on the gas-assisted extrusion (GAE) forming of the plastic micro-tube was investigated by numerical method. The three-phase fluids geometric model was built and same boundary conditions were imposed in the model. Under different viscous flow activation energies (VFAE), the influence of VFAE on the size changes of plastic micro-tube in the GAE were obtained. Moreover, the flow velocities, pressure, temperature, and viscosity distributions of melt were also gotten and analyzed. Results show that with the increase of viscous flow activation energy, the inner and outer radiuses all synchronously increase due to the increase of radial velocity and axial velocity. In addition, the temperature distribution slightly increases, which results in the decrease of the pressure and viscosity of melt.

To overcome the extrusion problems of plastic pipes, the double gas-assisted extrusion method was used in this paper. To investigate the effect of gas flow rate on the double gas-assisted extrusion forming of the plastic pipes, the numerical simulations based on the finite element method were performed. Numerical results show that with the increase of the gases flow rate, the inner radius increases and the outer radius decreases, which lead to decrease the wall thickness of plastic pipes. At the same time, the flow velocity changes of melt under the different gases’ flow rate were obtained and compared. To ascertain the mechanisms of shrinkage phenomenon of wall thickness, the normal stress and first normal stress difference distribution nephograms of melt under the different gases flow rates were obtained. Results show that the normal stress effect of assisted gases on the melt is the main reason that the wall thickness is decreased by the larger assisted gases flow rates.

Oil-contained solid wastes subsidiary produced in process of oil and gas exploration and production are classified as hazardous wastes. Oily solid waste is necessary to reduce the total petroleum hydrocarbon (TPH) content to required targets before discharging. A thermal desorption test equipment of electromagnetic heating in moving bed was set up, and estimated processing parameters of thermal desorption unit (TDU) based on thermal calculation. Constant wall temperature of heating bed was helpful for rapid thermal desorption disposal, and power output of heating bed was not constant on each section. Rapid thermal desorption tests of two samples were carried out on pilot equipment. Under the residence time of 12.5 minutes, sample #1 was processed at bed wall temperature of not less than 450 °C, TPH content could be reduced to 1%, and to achieve the same disposal effect, sample #2 should be processed at bed wall temperature of not less than 500 °C. The residence time was reduced to 7.2 minutes, TPH content of treated sample #1 could be reduced to less than 1% at bed wall temperature of 500°C, while the disposal effect of sample #2 was fail to reach the standard.

To ascertain the effect of annual width on the extradite swell of plastic tube, the 3D extrusion forming of plastic tube was numerically studied. The geometric models and finite element meshes with different annual widths were established. Under the same material properties, boundary conditions, and numerical methods, the extradite swell situations of plastic tube (i.e., inner radius, outer radius, and wall thickness) were obtained. Numerical results show that the extradite swell ratio of plastic tube decreases with the increasing of the annual width.

In this study, gas-assisted extrusion method was introduced into the extrusion of the hollow profiles. To validate the feasibility of the new extrusion method, 3D numerical simulation of the hollow profiles based on gas-assisted technique was carried out by using the finite element method. The Phan-Thien-Tanner (PTT) mode was selected as the construction equation. In the simulations, the physical field distributions of four different extrusion modes were obtained and analyzed. Results showed that the extrudate effect of traditional no gas- assisted mode was poor because the extrudate swell phenomenon is obvious and the physical field values are larger. For the gas-assisted of the inner wall, the extrudate swell of the melt was more obvious than that of the traditional no gas-assisted mode on account of the no-slip boundary condition on the outer wall. For the gas-assisted of the outer wall, the dimple effect of the inner wall is more obvious owing to the no-slip boundary condition on the inner wall. However, the extrusion effect of the double walls gas-assisted mode is very good because of the full-slip effect on the both walls.

A noncontact wireless passive pressure sensor based on alumina ceramic for pressure measurement is presented in this paper. A faithful pressure signal in harsh environment is captured through wireless sensing, and a novel antenna design method is developed to increase the measurement distance between the antenna and the sensor. The sensor is fabricated using a novel no-co-fired technology, and the properties of the alumina ceramic and platinum ensure the feasibility of the sensor in high-temperature environments. The experimental results show that the coupled distance between the antenna and the sensor can be up to 5.5 cm, and the designed sensor, featuring improved structural parameters, has a high responsivity (15.5 kHz kPa−1) in a pressure environment at room temperature. The sensor can be coupled with the antenna at 850 °C, which verifies the feasibility in high-temperature environments.

Traditional traffic emission inventory models aim to provide overall emissions at regional level which cannot meet planners' demand for detailed and accurate traffic emissions information at the road segment level. Therefore, a road segment-based emission model for estimating light duty vehicle emissions is proposed, where floating car technology is used to collect information of traffic condition of roads. The employed analysis framework consists of three major modules: the Average Speed and the Average Acceleration Module (ASAAM), the Traffic Flow Estimation Module (TFEM) and the Traffic Emission Module (TEM). The ASAAM is used to obtain the average speed and the average acceleration of the fleet on each road segment using FCD. The TFEM is designed to estimate the traffic flow of each road segment in a given period, based on the speed-flow relationship and traffic flow spatial distribution. Finally, the TEM estimates emissions from each road segment, based on the results of previous two modules. Hourly on-road light-duty vehicle emissions for each road segment in Shenzhen's traffic network are obtained using this analysis framework. The temporal-spatial distribution patterns of the pollutant emissions of road segments are also summarized. The results show high emission road segments cluster in several important regions in Shenzhen. Also, road segments emit more emissions during rush hours than other periods. The presented case study demonstrates that the proposed approach is feasible and easy-to-use to help planners make informed decisions by providing detailed road segment-based emission information.

The classical surface-embossed plane and concave grating are usually used as the diffraction grating in some spectrophotometers. But the minute cracks are produced on the surface of the gratings' grooves, which leads to generate the stray-light and decrease the efficiency of instrument. Therefore, a novel custom-built spectrophotometer for BCA is developed in this paper. Meanwhile, the volum holography transmissive(VHT) grating is used as the diffraction grating in this spectrophotometer. Additionally, a high resolution CCD and data acquisition (DAQ) card with combined the virtual software platform based on LabVIEW are used to design the spectral acquisition and analysis system. Experimental results show that the spectral range and the diffraction efficiency of the spectrophotometer for BCA are greatly increased. The spectral range of the spectrophotometer for BCA can reach 300-1000 nm, its wavelength resolution can reach 1nm. And, it uses the back-splitting-light technology and multi-channel parallel analysis. Compared with other same types, this spectrophotometer has many advantages, such as, higher efficiency, simpler algorithm, higher accuracy, cheaper cost and fewer stray-light and higher imaging quality, etc. Therefore, this spectrophotometer for BCA based on VHT grating will has the greatly potential values in the fields of the biochemical or medical research.

Breast cancer can be detected by B-mode ultrasonic imaging, X-mammography, CT imaging, and MRI. But some drawbacks existed in these methods, their applications was limited in some certain. So, a novel high resolution breast cancer detector (BCD) is developed in this paper. Meanwhile, an improved holography concave grating imaging spectrometer (HCGIS) is designed. In this HCGIS, the holography concave grating is used as the diffraction grating. Additionally, CCD with combined image acquisition (IAQ) card and the 3D scan platform are used as the spectral image acquisition component. This BCD consists of the light source unit, light-path unit, check cavity, splitting-light unit, spectrum acquisition and imaging unit, signal processing unit, computer and data analysis software unit, etc. Experimental results show that the spectral range of the novel BCD can reach 300-1000 nm, its wavelength resolution can reach 1nm, and this system uses the back-split-light technology and the splitting-light structure of holography concave grating. Compared with the other instruments of breast cancer detection, this BCD has many advantages, such as, compacter volume, simpler algorithm, faster processing speed, higher accuracy, cheaper cost and higher resolution, etc. Therefore, this BCD will have the potential values in the detection of breast disease.