查询词典 estimation of error

It is useful to solve accretion of estimation error and filter divergence in practice.

这将有助于解决卡尔曼滤波器在实际应用中估计误差增大和滤波发散等问题。

On the basis of analysis of the principle of TDOA location estimation and the feature of signal propagation in mobile communication environment, taking the system errors and environmental errors into account, we established the statistical model of TDOA error, and proved it is available by experiment.

针对公交车辆运行的特点，提出利用移动电话定位中的TDOA 定位技术对公交车辆进行定位。

Heating billet temperature cannot be detected in the hearth. Only by detecting temperatures of the stove side or hearth with estimation from mere experience could lead to great error on the measurement of billet temperature and affect the quality of post-processing accordingly; Overheating also exists in the heating process, and the quality of product is sway by overheating oxidation. Though infrared thermoscope is used to detect the temperature of billet when it is taken out of the stove, precision is still affected because of the oxide layer on the surface.

燃气与空气的配气量比例，一般通过人工调节，未实现按加热条件自动动态调节；无法在炉膛内检测被加热钢材的温度，只能通过检测炉壁或炉膛温度，再凭经验估计钢材温度，结果是钢板温度误差大，影响后续加工质量；钢材加热存在表面过烧现象，有时表面烧损、氧化严重，影响产品质量；尽管钢材出炉时，可用红外线测温仪来进行钢材表面温度检测，但因钢材表面存在氧化层，也影响钢材温度检测精度。

Through the stress calculation of a 3d jacket platform in wave, the change of load combination acting on the braces of multiplanar joints was observed, the influence of different load combination on the maximum stress and the location of hot spot was revealed, and the error in stress estimation caused by regarding multiplanar joint as uniplanar joint was analyzed, which shows the necessity of stress analysis to multiplanar joints.

本文通过一座波浪中的三维导管架平台结构的接头应力分析，考察了接头的载荷组合形式随波浪的变化，揭示了不同的载荷组合形式对接头最大应力及其热点位置的影响，分析了将空间接头作为平面接头来估算最大应力时引起的误差，从而说明了进行空间接头应力分析的必要性。

Density Functional Theory method was used to optimize the geometries of 209 PCDE molecules, 209 PBDE molecules and 75 PCDD molecules at the B3LYP/6-31G* level. Using computed structural parameters as theoretical descriptors, the forward stepwise multiple regression technique was adopted to obtain QSPR models of environmental partition properties for these POPs by using GQSARF 2.0 and SPSS12.0 for windows programs. The obtained QSPR models are as follows:(1) QSPR models for predicting subcooled liquid vapor pressure, n-octanol/water partition coefficients lgK_(ow and subcooled liquid water solubilities -lgS_(w,l of PCDEs, of which correlative coefficients (R~2) are 0.988, 0.958 and 0.959 and the root-mean-square-error of estimation are 0.134, 0.116 and 0.327 respectively.(2) QSPR models of lgPL and n-octanol/air partition coefficients lgK_(oa for PBDEs, which both contain three structural parameters. The values of R2 for the two models are both 0.997 while the values of RMSEE are 0.073 and 0.062 respectively.(3) QSPR models of lgKow and–lgS_ for PCDEs, which both have one variable (mean molecular polarizability,α). The values of R~2 for the two models are 0.978 and 0.866 and the values of RMSEE are 0.300 and 0.270 respectively.(4) The molecular structures of 24 substituted naphthaline compounds were optimized using Hartree-Fock and DFT methods at four different levels and the same means was used to obtain four three-parameter (EHOMO, q~+ andα) QSPR models of lgK_. The model at the HF/6-311G** level is the best one of which R2 is 0.9662 and RMSEE is 0.380.(5) QSPR study for environmental partition properties of PCDEs was also performed using position of Cl substitution method in which simple parameters of substitution position were taken as descriptors. The multiple linear regression was performed with GQSARF 2.0 and SSPS 12.0 for windows programs to obtain QSPR models of lgP_L, lgK_ and–lgS_ for PCDEs of which R~2 are 0.991, 0.983 and 0.965 and RMSEE are 0.311, 0.100 and 0.300 respectively.

采用密度泛函理论方法在B3LYP/6-31G*水平上对PCDEs、PBDEs和PCDDs的分子结构进行了全优化计算，以计算得到的量子化学参数作为理论描述符，采用GQSARF 2.0和SPSS 12.0 for windows统计程序进行正向逐步回归分析，建立了这些POPs的环境分配性质的QSPR模型：(1) PCDEs的过冷液体蒸汽压、正辛醇/水分配系数lgK_(ow和水溶解度-lgS_(w，l的QSPR模型，这3个QSPR模型的相关系数(R2)分别为0.988、0.958和0.959，估计的均方根误差分别为0.134、0.116和0.327；(2) PBDEs的lgPL和正辛醇/空气分配系数lgK_(oa的QSPR模型，这两个模型都包含三个分子结构参数，其R~2都为0.997，RSMEE分别为0.073和0.062；(3) PCDDs类化合物的lgK_和-lgS_w的QSPR模型，两个模型都只含一个变量，其R~2分别为0.978和0.866，RSMEE分别为0.300和0.270；(4)采用Hartree-Fock和DFT方法，在4种不同水平上优化计算了24个取代萘系列化合物的分子结构，采用上述同样的方法分别建立了四种水平上的三变量lgK_模型，通过比较得到，在HF/6-311G**水平计算得到的模型最好，R为0.966，RSMEE为0.380；(5)同时，采用氯原子取代位置方法对PCDEs的环境分配性质进行QSPR研究，建立了PCDEs的lgPL、lgK_和-lgS_的QSPR模型，其R~2分别为0.991、0.983和0.965，RSMEE分别为0.110、0.100和0.300。

It is one of the main methods to improve the performance o f strapˉdown inertial navigation system for compenˉ sating random drift and bias of MEMS IMU. For improving performance of MEMS IMU and that of the INS, the error estimation and compensation of MEMS IMU with autoregressive proces ses modeling method was deeply studied.

为了提高IMU精度，进一步提高惯性系统精度，采用时间序列理论中的AR模型对M EMS IMU的误差估计和补偿作了深入的研究，并与径向基神经网络建模方法分析比较。

The precise satellites clock error estimation algorithm of navigation satellites is studied in this paper. The computation of precise satellites clock error based on the non-difference phase is realized and the results are compared with the products provided by IGS analysis centers.

研究了导航卫星精密钟差的估计算法，编程实现了基于非差载波相位的精密卫星钟差的解算，并同IGS若干分析中心提供的精密钟差产品进行了比较。

The invention performs pseudo bit error rate statistic by utilizing the message of multi sampling points in each modulation symbol of discretization system, and again performs one-to-one mapping by utilizing corresponding relation between the pseudo bit error rate and the signal-to-noise ratio, thereby obtaining signal-to-noise ratio estimation value.

本发明利用了离散系统每个调制符号中多个采样点的信息进行伪误码率统计，再利用伪误码率与信噪比之间的对应关系进行一一映射，从而得到信噪比估计值。

The author briefly introduces the channel estimation methods and decision criterions of both SISO-OFDM system and MIMO-OFDM system, and gets the compared figures about performance of mean square error and bit error ratio.

作者简要介绍了传统SISO-OFDM系统和MIMO-OFDM系统信道估计的方法和判决准则，并给出了这些算法之间的均方误差和比特误码率的性能比较曲线。

For chirp radiator direction-finding using an ARM interferometer seeker, the cause of the direction-finding error using traditional direction angle estimation is studied, and the relationship between the direction-finding error and the integration time is analyzed, especially for the boundary condition that the integration time of phase discriminators gets the maximum value.

针对ARM干涉仪导引头对chirp信号辐射源的测角问题，从几何关系与信号分析两方面揭示了传统方向角估计方法产生测角误差的机理，分析了干涉仪测角误差随鉴相器积分时间变化的关系，重点对积分时间最长这一极端情况开展研究。

Since historical times,England ,where the early inhabitants were Celts, has been conquered three times .

从有历史以来，英国，在此地早期居住的是凯尔特人，已经被征服了三次。

Bluetooth OBEX File Transfer Enables the sending and receiving of files on your phone via Bluetooth.

蓝牙OBEX文件移动允许经过蓝牙传送和接受文件。。。。