基于GPS基线向量的舰载火箭弹姿态测量方法

提出一种利用GPS载波信号相位差测量技术进行实时确定弹体姿态的方法。通过对载波相位差测量航向和姿态原理的分析,建立GPS姿态确定的单差模型,推导采用GPS多天线姿态测量技术实时获取弹体飞行姿态的解算算法,应用最小二乘法估计解算基线向量,然后对GPS姿态估计算法进行仿真计算。仿真结果验证了模型、算法的正确性和有效性。     

基于MEMS加速度计和陀螺仪的姿态检测系统

本文根据微机电系统(MEMS)加速度传感器的工作原理和特点,对姿态检测系统的原理、组成以及数据采集进行了研究.提出了一种基于MEMS三轴加速度传感器和陀螺仪的倾角检测系统的实现方法.采用加速度计和陀螺仪的数据融合,有效地提高姿态检测系统的检测精度.     

浅埋矩形顶管群密贴施工的顶推力分析研究

为明确矩形顶管群密贴施工中顶管顶推力的发展规律与影响因素,以圆形顶管顶推力计算理论为基础,依托实际的试验工程背景,分7个工况分别进行顶推力的统计分析。通过多工况理论估算与实测数据对比,验证管顶推力的实测值与理论值在规律上的一致性,同时得出该理论值较实测值偏小的结论。针对试验工程中出现的减摩失效、顶管背土、姿态异常等问题展开研究,通过对比分析不同工况实测顶推力发展规律,最终得出: 就本工程而言,减摩泥浆的减摩效果明显,顶推力减小约38.2％; 顶管背土与顶管姿态对顶推力具有较大的负面影响,其中,顶管背土导致每节顶推力增加约16.7％,顶管姿态异常引起顶推力额外增加17.8节的理论推力。     

DGPS RTK技术进行天津港潮位测量的应用分析

针对天津港水深测量的实际情况,对DGPS RTK技术能否应用于天津港潮位测量进行试验分析,为近海海域的潮位观测提供了一种新的方法。     

GPS航姿测定方案及误差分析

该文提出了用两台ＧＰＳ接收机测量同一颗卫星所得的伪距差求算舰船的航向角和姿态角的方法，推证了航向角和姿态角的计算公式。通过误差分析，讨论了影响ＧＰＳ航姿测定的各项误差，提出了ＧＰＳ航姿测量方案。     

反射波初至时刻判断中的信号对比法

在地表波动测试中,若不考虑上部岩层不均匀性,与发射点距离相等的测点上测得的振动信号理应吻合,而当某测点最先有节理面反射纵波传播至时,其振动信号就与其它测点振动信号发生偏离,故可通过信号对比判断出该测点处节理反射波初至时刻,该方法应用于实测信号,判断出的节理反射波初至时刻误差<1%.     

Estimating metro passengers’ path choices by combining self-reported revealed preference and smart card data

With the help of automated fare collection systems in the metro network, more and more smart card (SC) data has been widely accumulated, which includes abundant information (i.e., Big Data). However, its inability to record passengers’ transfer information and factors affecting passengers’ travel behaviors (e.g., socio-demographics) limits further potential applications. In contrast, self-reported Revealed Preference (RP) data can be collected via questionnaire surveys to include those factors; however, its sample size is usually very small in comparison to SC data. The purpose of this study is to propose a new set of approaches of estimating metro passengers’ path choices by combining self-reported RP and SC data. These approaches have the following attractive features. The most important feature is to jointly estimate these two data sets based on a nested model structure with a balance parameter by accommodating different scales of the two data sets. The second feature is that a path choice model is built to incorporate stochastic travel time budget and latent individual risk-averse attitude toward travel time variations, where the former is derived from the latter and the latter is further represented based on a latent variable model with observed individual socio-demographics. The third feature is that an algorithm of combining the two types of data is developed by integrating an Expectation-Maximization algorithm and a nested logit model estimation method. The above-proposed approaches are examined based on data from Guangzhou Metro, China. The results show the superiority of combined data over single data source in terms of both estimation and forecasting performance.     

Research on integrated navigation method for AUV

The principles of the SINS/DVL integrated navigation system are introduced, and the compass status accuracy is compared. When the heading is changed, the dead reckoning algorithm using the heading information of the SINS （Strapdown inertial navigation systems） and DVL （doppler velocity log） is adopted to substitute the SINS/DVL integrated system. The simulation results show that the method can improve the accuracy of integrated navigation system when AUV （autonomous underwater vehicle） is in motion.     

Group attitude and hybrid sanctions: Micro-econometric evidence from traffic law

In many legal domains hybrid sanctions – i.e. the joint use of both monetary and non-monetary sanctions – are usually applied. We suggest that one possible rationale behind this form of sanction is targeting group-specific deterrence. For some groups of agents, hybrid sanctions act indeed as a self-selection mechanism such that deterrence is obtained only after a critical threshold of infractions is reached. We apply our model to traffic law infractions and further test it, performing a micro-econometric analysis on a unique dataset of a representative sample of 50,000 Italian drivers, over six years (2003–2009), after the introduction of a penalty points system. Our findings empirically confirm our theoretical predictions. When repeated infractions are at stake, well-designed hybrid sanctions, such as the penalty point system designed for traffic law enforcement, may indeed increase overall deterrence. Our results shed new light on the role of the combined monetary and non-monetary sanctions to perform general and specific deterrence.     

基于新型卡尔曼滤波器的组合导航系统

对SINS/DGPS/Magnetometer全组合导航系统进行分析,建立了相应的误差模型和系统观测模型,并提出了一种新的扩展卡尔曼滤波方法对其进行处理,仿真结果表明,该设计改善了系统性能,提高了导航定位的精度、可靠性。