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Affine-invariant matching is one of the challenging fields for image matching. Although several algorithms (ASIFT, Fair-SURF) have been proposed and achieved expressive performance, all these method need to simulate perspective changes and exhaust all possible match which is of high computation complexity (O(N2)). In this paper, we proposed a new method to introduce global descriptor to filter out much unnecessary coarse matches for the matching procedure. Specially, the computation complexity of matching procedure in our method reduces significantly to O(N). But, the experiment result shows that the proposed method can achieve comparable performance to ASIFT at much lower cost.

A unified control structure for two-stage power converter system (PCS) is proposed which incorporates both charging and discharging modes within the same controller. Detailed modeling process is presented using sub-system approach. Power feed-forward compensation with direct battery current reference is engaged to enable fast response to power change on battery side, thus reducing DC bus voltage fluctuation during transients. Simulation and experiments show that the proposed control structure can effectively improve dynamic response without compromising steady-state performance.

The effect of metal ions in dyebath on the color of wool fabrics dyed with six kinds of common wool dyes was investigated. The dyes chosen were acid mordant dyes, Palatin dyes, Acidol dyes, Polar dyes, Lanasol dyes, and Lanaset dyes. The dyes were divided into 23, and fabrics were treated separately with these dyes according to the corresponding dyeing process. The metal ion of Cr6+, Cr3+, Cu2+, Fe3+, and Al3+was added separately into the dyebath, the content of which was 3 mg/L, 30 mg/L, and 300 mg/L. The differences in color between the fabrics dyed using the metal-contain-process and the metal-free-process were compared. The color difference is positively correlated with the metal ion content. When the metal ion content was 3 mg/L, the color difference values (ΔE) of most dyed fabrics were less than 1.7±0.3 of CIELAB. Moreover, color fastness was greater than 4, which means that the effect of the metal ions to color difference is acceptable. When the metal ion content was 300 mg/L, the ΔE values of most dyes were greater than 13.6±1.0 of CIELAB, which means that the metal ions have obvious effects on color difference. When the metal ion content was 30 mg/L, the ΔE values ranged from 1.7±0.313.6±1.0 of CIELAB. Based on the recommendation of theGB250-1995 Gray Scale for Assessing Change in Color(equivalent to the ISO 105/A02-1993 Textile-tests for Color Fastness-grey Scale for Assessing Change in Color), the ΔE value 1.7±0.3 of CIELAB and Grade 4 color fastness were used as the threshold to assess the results. When the metal ion content was 3 mg/L, Cu2+and Fe3+had low influence on the Palatin dyes, in which the color difference and the color fastness were less than the threshold. Meanwhile, Cu2+and Fe3+had excessive effects on the other kinds of dyes, with the ΔE values beyond the threshold. However, Cr3+had excessive influence on the Palatin dyes, with the color difference and the color fastness exceeding the threshold. In contrast, Cr3+had a smaller effect on the other kinds of dyes, with the ΔE values conforming to the threshold. Al3+had a significant effect on the acid mordant dyes, with the ΔE values beyond the threshold. In contrast, Al3+had a smaller effect on the other kinds of dyes, which were within the threshold. Cr6+had no significant effect on the kinds of dyes, in which the ΔE values did not exceed the threshold. When the metal ion content was 30 mg/L or 300 mg/L, we obtained mixed results. The color difference and color fastness values of kinds of dyes in the present study met the threshold, whereas some kinds of dyes were not within the threshold. The result has practical utility for setting the standards for water recycling in the wool dyeing industry.

In this study, the image definition of animal fibers captured by Axioskop 2 MOT PLUS differential interference contrast (DIC) light microscope using 1-bromonaphthalene, diethylene glycol, n-decyl alcohol, and ethylene glycol monomethyl ether as embedding medium, respectively, is compared with the image definition obtained using paraffin wax, the reference embedding medium. The effects of the four kinds of embedding media on the image definition of camel cashmere, yak cashmere, wool, and cashmere are also analyzed. Results show that topographical feature, scale structure, and pigmentation are better visualized when n-decyl alcohol is used as embedding medium compared to when the other kinds of embedding media are used. This meets the requirement of computer image analysis method for the identification of camel cashmereand yak cashmere fibers. Furthermore, the image definition of wool and cashmere is clearly improved when n-decyl alcohol is used as the embedding medium compared to when paraffin wax is used in the same condition.

Using ANSYS-FLOTRAN CFD program, the finite element simulation is conducted by means of a series of procedures, such as three-dimensional model building of airflow level posture sensor, network modifying, loads applying equation solving, the flow field in three-dimensional hermetic chamber of sensitive element of airflow level posture sensor in different acceleration and inclination is Calculated, The numerical results show that for the sensor of airflow level posture sensor, the effect of acceleration and inclination is similar. Both of them can change the flow field of sensor, and will output a corresponding voltage. The simulation result of three-dimensional modeling is more comprehensive and accurate, which provides more reliable basis for practical research of the airflow level posture sensor.

Based on operation computation of signal chip MSC1214, Output signal processing of air level posture sensor is carried on, including temperature –zero voltage compensation, temperature-sensitive voltage. The results show that the change quantity of sensitivity drops to ≤1%; the operating temperature scope expands from the normal temperature to 30°C; in this temperature range, the change quantity of zero voltage drops from ≤0.23V to ≤0.01V, depressing the influence caused by temperature and improving the measurement accuracy of air level posture sensor.

Using ANSYS program, the finite element simulation based on thermoelectric coupling is conducted by a series of procedures, such as three-dimensional model building of airflow level posture sensor according to the actual size of the proportion, network modifying, loads applying and equation solving. The sensitive mechanism of airflow level posture sensor is explained by finite element method. The numerical results show that compared with two-dimensional modeling, the simulation result of three-dimensional modeling and thermoelectric analysis methods are more comprehensive and accurate, which provides more reliable basis for practical research of the airflow level posture sensor.

Micro mechanical airflow level posture sensor, combined with micro mechanical skill and air pendulum, the volume is small, the structure is compact, the craft is simple and uniformity of sensitive component is good. But it can be only sensitive to tilt posture around the specific sensitive axle. In order to realize the omni-directional survey, this article utilizes the MEMS tilt-sensitive component to withdraw omni-directional and carries on sensitivity compensation of omni-directional signal. The results show that: resolution is better than 0.1 °; nonlinear is small than 1.2%; range of angle measurement is from 0 °to360 °, realizing survey of omni-directional level measurement.

Using ANSYS-FLOTRAN CFD program, the finite element simulation is conducted by a series of procedures, such as three-dimensional model building of airflow inclination sensor, network modifying, loads applying and equation solving. The flow field caused by the two heats in three-dimensional hermetic chamber of sensitive element of airflow level posture sensor is Calculated, FEM analysis has been obtained. The numerical results show that compared with two-dimensional modeling, the simulation result of three-dimensional modeling are more comprehensive and accurate, which provides more reliable basis for practical research of the airflow inclination sensor.

Using ANSYS program, the finite element simulation based on Fluid-Solid coupling is conducted by a series of procedures, such as three-dimensional model building of airflow level posture sensor according to the actual size of the proportion, network modifying, loads applying and equation solving. The flow field in three-dimensional hermetic chamber of sensitive element of airflow level posture sensor is calculated. The numerical results show that: 1) The velocity difference of air flow at two heat source changes with the tilt angle, the difference between airflow velocity increases with the increase of the tilt angle. 2)Compared with two-dimensional modeling, the simulation result of three-dimensional modeling and fluid-solid analysis methods are more comprehensive and accurate, which provides more reliable basis for practical research of the airflow level posture sensor.

The method of interpolation was used in the process of software compensation of temperature in order to improve the environmental performance of air level posture sensor. Two algorithms including Lagrange interpolation and piecewise linear interpolation were calculated and compared in Matlab software, and then the optimization scheme could be achieved. The result showed that although the curse of Lagrange interpolation included all the given data positions, the Runge phenomenon in polynomial interpolation made the accuracy of interpolation lower. Piecewise linear interpolation reflected the relationship between environment and zero voltage more accurately. Piecewise linear interpolation not only can be used to improve the accuracy of software compensation of air level posture sensor.

In order to improve linearity of output signal of air level posture sensor, this article do the research about linearity to output signal based in the operation function of single chip of MSC1214, uses the ORIGIN software to process experiment data to get the linearity curve. The result indicates that misalignment of sensor drops to ≤1% in full scale scope, linearity between output voltage and the input angle has the enormous improvement, depressing the influence caused by angle approximation and improving the measurement accuracy of air level posture sensor.

Using ANSYS-FLOTRAN CFD program, the finite element simulation is conducted by a series of procedures, such as three-dimensional model building of airflow inclination sensor, network modifying, loads applying and equation solving. The flow field in three-dimensional hermetic chamber of sensitive element of airflow level posture sensor is calculated, FEM analysis has been obtained. The numerical results show that under the buoyancy lift affecting, the direction of nature convection gas always keeps the vertical upward in two-dimensional enclosure, nature convection gas has the pendulum characteristic, and when the dimensional enclosure is inclined, temperature distribution at the several points in dimensional enclosure will change with the tilt angle. The pendulum characteristic can be utilized to measure the level posture by the airflow level posture sensor.

Sensitive principle of air level posture sensor is introduced and test to the actual manufacture's sensor is carried on. The test result indicates that the temperature’s influence to the sensitivity is suppressed basically; the operating temperature scope expands from the normal temperature to 30°C; the resolution surpasses over 0.1°; misalignment of air level posture in full scale scope is smaller than 1%，measuring range the angle of tilt may achieve to 20°.

The paper firstly introduced the sensitive mechanism of micromachined airflow omnibearing level posture, and compare several sense organ’s structure schematic design, and the best structure design is proposed. At last, it is testified that the design of micromachined airflow omnibearing level postrue sensor achieved the following performances: resolution

The paper firstly introduced the sensitive mechanism of micromachined airflow omnibearing level posture. Adopt micro-machine technology, octagonal sense organ is sensitive to omnibearing level posture. Signal processing circuit is composed by pre-signal circuit and digital circuit, to obtain voltage, omnibearing signal synthesis and resolution compensation of omnibearing tile angle signal. It is testified that: resolution

Micromachine airflow tilt sensor which can be sensitive to tilt angle is described. Adopt micro-machined technique two deep groove are corroded on the silicon plate, and two cantilever beams of metal film heated hot wire is set up at each deep groove. Semicircle airtight space forms sense elements. Through Wheatstone bridge, we get the tilt output voltage. Single-chip computer and temperature sensor constitute compensation circuit to achieve temperature compensation and linear compensation. The test showed the sensor’s performance is as follow: measuring range is ±30,resolution

The paper firstly introduced the sensitive mechanism of micromachined airflow omnibearing level posture. There is a non-closure annulus heat source in the airtight space, and around the heat source, there are eight parallel heat resistance wire composed omnibearing level posture sense organ. Signal processing circuit is composed by pre-signal circuit and digital circuit, to obtain voltage, omnibearing signal synthesis and resolution compensation of omnibearing tile angle signal. It is testified that: resolution

Two-dimension level posture sensor which can be sensitive to two vertical-directional tilt angle at one time is described. Adopt micro-machined technique two deep groove are corroded on the silicon plate, and two cantilever beams of metal heated hot wire is set up at each deep groove. Semicircle airtight space forms sense elements. Through two Wheatstone bridge, we get the tilt output voltage of x axis and y axis. To overcome environmental factors, a series of signal processing methods are proposed ,such as: zero temperature compensation, sensitive temperature compensation and linear compensation. The test about the sensor showed the sensor’s performance is as follow: resolution