科创中国

Vehicle mass is an important parameter in vehicle dynamics control systems.Although many algorithms have been developed for the estimation of mass,none of them have yet taken into account the different types of resistance that occur under different conditions.This paper proposes a vehicle mass estimator.The estimator incorporates road gradient information in the longitudinal accelerometer signal,and it removes the road grade from the longitudinal dynamics of the vehicle.Then,two different recursive least square method(RLSM)schemes are proposed to estimate the driving resistance and the mass independently based on the acceleration partition under different conditions.A 6 DOF dynamic model of four In-wheel Motor Vehicle is built to assist in the design of the algorithm and in the setting of the parameters.The acceleration limits are determined to not only reduce the estimated error but also ensure enough data for the resistance estimation and mass estimation in some critical situations.The modification of the algorithm is also discussed to improve the result of the mass estimation.Experiment data on a sphalt road,plastic runway,and gravel road and on sloping roads are used to validate the estimation algorithm.The adaptability of the algorithm is improved by using data collected under several critical operating conditions.The experimental results show the error of the estimation process to be within 2.6%,which indicates that the algorithm can estimate mass with great accuracy regardless of the road surface and gradient changes and that it may be valuable in engineering applications.This paper proposes a recursive least square vehicle mass estimation method based on acceleration partition.

Durning the design process of hydrostatic rotary worktable,the processing and assembly tolerance,(the offset of worktable and the gap of the oil film's thickness)is ignored.But it will cause that the real bearing of oil pocket deviates from the initial design value,and then the performance of rotary worktable will be reduced significantly.Up to now,no effort is found toward the research of influence of the processing and assembly tolerance on the performance of the rotary worktable.So the hydrostatic oil film is assumed as the elastomer in this paper,and then the bearing capacity of the oil pocket is studied with and without the mass offset of the worktable by taking an expression between the bearing capacity and the oil film's thickness of the oil pocket as the deform compatibility equation.The influence of the processing tolerance of the oil sealing belt's gap on the bearing capacity of the oil pocket is analyzed.In the light of the liquid hydrostatic worktable of Gantry Moving Milling Center using on the scene,the oil pocket's pressure of the worktable is tested using Rotary Worktable Test System under the circumstance of the mass offset of the worktable and the gap tolerance of the oil sealing belt,and then the equivalent offset of worktable,the average pressure of the oil pocket and the actual thickness of the oil film are analyzed respectively.The test results show that the bearing capacity component of the oil pocket caused by G is consistent,and the component caused by M is relative to the position of the oil pocket.When the oil sealing belt's gap is larger than the theoretical value,the bearing capacity of the oil pocket is smaller than the others;whereas the bearing capacity of the oil pocket is larger than the others.The maximum and minimum equivalent offsets are 0.256 4 mm and 0.047 5 mm,respectively,and the average oil pocket pressure varies from 0.345 MPa to 0.460 MPa,the maximum and minimum value of the actual oil film thickness are 109.976?m(No.7 oil pocket)and 93.467?m(No.10 oil pocket),respectively.The research results can be used to detect the offset of the worktable and the actual thickness of the oil film under processing and assembly tolerance,and provides a basis way for detecting the processing and assembly tolerance of rotary worktable signing reasonably of Gantry Moving Milling Center.

建立了茶叶中34种农药多残留的气相色谱质谱分析方法.茶叶样品用乙腈一次性提取后,经Carb/PsA固相萃取小柱净化,气相色谱质谱定性定量.添加回收试验的结果表明:34种农药的平均回收率70%124%,相对标准偏差为0.2%-14.9%.方法的检出限为0.1-25.0μg/kg.该方法的灵敏度、准确度和精密度均符合农药残留测定的技术要求.

针对当前交叉口信号灯模糊控制器结构参数固定的缺陷,提出了一种新的分级模糊控制器用于交叉路口交通流的控制与优化,该控制器能有效地减少规则数,易于提取模糊规则,能够显著改善交叉路口的通行能力.仿真实验结果证明该模型是有效的.

利用第一性原理计算方法密度泛函理论的局域密度近似计算了纤锌矿氮化铝(AlN)、氮化镓(GaN)、氮化铟(InN)及其合金在双轴应变下的电子有效质量.对于GaN和AlN,张应变使电子有效质量增大而压应变使电子有效质量减少,但却使InN电子有效质量在张应变和压应变下都增大.由于三元合金(AlxGa1-xNx InxGa1-xN和AlxIn1-xN)与GaN异质结的新颖特性,同时计算了三元合金在松弛和应变下电子有效质量的变化趋势.受制于GaN基板的平面应力,外延AlxGa1-xN和AlxIn1-xN电子有效质量将减少,而InxGa1-xN电子有效质量增大,且随着In含量变大而更显著.对铟氮化合物应变下电子有效质量异常的机制也做了讨论.

建立了蔬菜干制品中18种有机磷农药和拟除虫菊酯农药残留的在线凝胶渗透色谱一气相色谱/质谱(GPC-GC/MS)分析方法.样品以乙腈为提取剂超声波高速匀浆提取,提取液经ENVI.Carb固相萃取柱净化,除去样品中大部分的色素等干扰基质,再经在线GPC进一步净化除去大分子干扰物质,有效降低了样品基质带来的背景干扰.采用外标法定量,在质量浓度为0.02mg/kg,-0.5mg/kg有良好的线性关系,加标水平为0.4mg/kg时,18种农药的回收率基本都在80%-130%,相对标准偏差小于10%,检出限为0.001mg/kg-0.026mg/kg.经实验证明,该方法是一种快速,准确,灵敏度高的同时检测梅菜干中多种农药残留的检测方法.