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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

In this paper, the effect mechanism of environmental temperature on the sensitivity of the airflow level posture sensor is explained. Using ANSYS-FLOTRAN CFD program, the temperature field and the stream field in sensing element of the sensor under the effect of the different temperatures with tilt angle of 10°/S, has been obtained by a series of procedure, such as model building, meshing, loads applying and equation solving. The results are as follow: In a constant input of tile angle, the temperature field and the stream field in sensing element of the sensor change in different ambient temperatures; With the increase in temperature, airflow rate in sensing element declines, Conversely, with the ambient temperature decreases, airflow rate in sensing element increases wholly; With the increase in temperature, the airflow rate difference of two detecting hot wires decreases, detecting bridge’s output voltage decreases, the sensitivity of the sensor reduces too; Conversely, with the ambient temperature decreases, the airflow rate difference of two detecting hot wires increases, detecting bridge’s output voltage increases, the sensitivity increases too; The sensitivity of the sensor with an average temperature change rate is 0.55mV/°/S/?. This paper provides the theoretical and experimental basises for the further temperature compensation , reducing the temperature drift of the airflow level posture sensor.

The temperature and fluid fields in a sense organ with different environmental temperatures are calculated by using Finite Element Method. The results are as follow: In a constant input of angular velocity, the temperature and fluid fields change with environmental temperature and fluid fields change with environmental temperature; The airflow rate difference of two detecting hot wires minishes with temperature increasing, and detection bridge’s output voltage decreases too, leading to impreciser sensitivity ; Conversely, the airflow rate difference of two hot wires increases with temperature decreasing, and the output voltage increases too, leading to preciser sensitivity; The average change rate of sensitivity with temperature is 0.0336mV/°/S/?, when the angular rate is 20°/S.

The sensitive mechanism of micro- machined airflow accelerometer is explained. Using the finite element method, the stream field by heat source, with different input accelerations, has been obtained. The numerical results are as follows: Without acceleration, the velocities of airflow at two thermistors are equal, so the current of both thermistors are also equal. The output of the bridge circuit is zero. With input acceleration, the velocity difference of airflow at two thermistors will change with the acceleration, so lead to changing of the current difference of both thermistors; the bridge outputs a voltage signal of corresponding to the acceleration. This calculated method provides a new road for optimization of micro-machined airflow accelerometer.

To investigate the effects of lycopene on T lymphocyte subpopulations and pulmonary alveolar macrophagic (PAM) functions in rats with acute lung injury (ALI).Rats were randomly divided into the following groups. (1) Control group, (2) ALI model group, (3) Low dose group,(4) Mid dose group and (5) High dose group. Control group and ALI model group were treated with solvent of lycopene, and the other groups were gastrically incubated with lycopene. Thirty-five days later, control group were given physiological saline, ALI model group and lycopene administrated groups were injected with lipopolysaccharide (LPS) (6.0 mg/kg) to induce ALI. One hour, four hours or six hours after LPS or physiological saline challenged, abdominal aorta blood for measuring lymphocyte subpopulations and bronchoalveolar lavage fluid for measuring function of PAM were gathered respectively.(1) At h 1, the percentages of CD3(+), CD4(+) and CD8(+) of lycopene administrated groups compared with control group were not significantly different. At h 4, the percentage of CD4(+) was similar to that at h 1. As for the percentages of CD3(+), except high dose group [(28.8+/-9.9)%] was significantly lower, low dose, mid dose and ALI model group showed no significant difference compared with control group[(39.5+/- 4.5)%]. The percentages of CD8(+) of ALI model and lycopene administrated rats, separately (10.2+/-3.9)%, (10.3+/-2.8)%, (9.8+/-2.8)%, (10.1+/-3.5)% , had been significantly reduced compared with control group[(15.1+/-2.5)%]; between ALI model and lycopene administrated groups there was no significant difference. The instance at h 6 was the same as that at h 4. The percentage ratios of CD4(+) T-lymphocyte to CD8(+) T-lymphocyte of ALI model rats were not significantly different compared with control group or lycopene administrated groups at h 1 and h 6. At h 4, the ratio of the CD4(+) and CD8(+) in Low dose and Mid dose groups had significant difference and ALI model, high dose hadn't when they were compared with control group. (2) Lycopene increased the phagocytic function of PAMs significantly at h 1(P0.01), the optical density of PAM of control group, ALI model group, low dose group, mid dose group, high dose group was 0.136+/-0.025, 0.215+/-0.095, 0.239+/-0.052, 0.275+/-0.068 and 0.297+/-0.049; what happened at h 4 was similar to that at h 1; Phagocytic function of PAM of lycopene administrated groups was increased compared with control group. (3) The concentrations of tumor necrosis factor-alpha (TNF-alpha) in control group, ALI model group, low dose group, mid dose group, high dose groups were 1.50+/-0.30, 1.87+/-0.30, 1.76+/-0.40, 1.74+/- 0.38,1.62+/-0.35 microg/L;and those of IL-8 were 0.82+/-0.08, 0.99+/-0.14, 0.82+/-0.16, 0.84+/-0.16, 0.83+/-0.11 microg/L. The concentrations of TNF-alpha and interleukin-8 (IL-8) in BALF were decreased by lycopene, especially the levels of IL-8 were reduced significantly.Lycopene might attenuate lipopolysaccharide-induced impairment of lungs and improve ALI prognosis by increasing the phagocytic function of PAMs significantly and restraining the secretion of TNF-alpha and IL-8.

Lp(a) receptor and LDL receptor on rhesus monkey liver cellular membrane were studied by Western blotting, to investigate whether Lp(a) and LDL metabolize through the same route. The experiment demonstrated Lp(a) receptor ( 300kD) and LDL receptor ( 185kD) to be different kinds of receptors. The result reveals that Lp(a) has its own metabolic pathway.