光测遥测数据联合计算速度的方法

提出了利用遥测的过载、俯仰角信息和光测的坐标联合计算弹道关机段速度的方法，从遥测结果的系统误差、随机误差和数值积分的截断误差三万面对剩余误差的影响进行了精度分析，并给出了速度精度的算法。     

Efficient model reduction in non-linear dynamics using the Karhunen-Loève expansion and dual-weighted-residual methods

 We look at the task of computing the time-evolution of a non-linear system for a long time, in our case under random external influences. Our specific example is the fatigue evaluation of a wind turbine. To facilitate such a computation, we look at a reduction of the computational effort by projecting everything on a low-dimensional basis. In this case we take the Karhunen-Loève basis generated from running the model a little while under the random loading. It is important that the error which is caused by this reduction process can be controlled. We estimate the error by dual or adjoint methods. This in turn allows the process of model reduction to be performed adaptively. Dedicated to the memory of Prof. Mike Crisfield, for his cheerfulness and cooperation as a colleague and friend over many years.     

Design Errors: Inefficiency or Carelessness of Designer?

Design defects are experienced in many projects; the difference is only in the extent of occurrence. This technical note discusses a design error case in a building project in Nepal, where the designer made the wrong assumptions in roof treatment work for waterproofing as well as for heat insulation purposes. From the investigation of the problem, it was found that the waterproofing polymer was not applied directly over concrete slab top. Use of heavy concrete block as a heat insulation material also helped to increase the leakage problem. The problem evoked loss of prestige for project officials, the design consortium, and the contractor.     

微波着陆导引系统测角误差分析

某型无人机的导引系统需要具备可靠、精密、可用等特点。文中首先对比了现行的三种导引系统，接着说明微波着陆系统（MLS）和所有的无线电测量系统一样，不可避免地存在系统误差。从微波着陆系统工作原理出发，分析讨论了角度测量过程中存在的误差源，及其所影响到的角度计算因子。进而给出了来自不同误差源的误差概算，最终结合系统测角精度要求，得出了相关设备的参数选择参考。     

工艺过程中假废品的研究

对机械零件加工过程中出现的假废品现象进行了分析和研究,并提出了判别的方法.     

精镗孔尺寸误差预测补偿技术的研究概况与趋势

提出了精镗孔尺寸误差预测补偿技术存在的主要问题，指出了今后所需研究的主要内容及关键技术。     

多量程数据采集记录装置的设计

通常的数据采集与记录装置不易实现多量程测量。通过对标度方程进行分析得知,要改变量程只须改变两个参数——标度因子和量程下限。我们设计了一个使用单片机的多量程数据采集和记录装置,能处理多达256种量程。本文叙述了算法分析、硬件和软件的设计以及该装置的性能指标。     

Error Concealment Based on Semantic Prioritization with Hardware‐Based Face Tracking

With video compression standards such as MPEG‐4, a transmission error happens in a video‐packet basis, rather than in a macroblock basis. In this context, we propose a semantic error prioritization method that determines the size of a video packet based on the importance of its contents. A video packet length is made to be short for an important area such as a facial area in order to reduce the possibility of error accumulation. To facilitate the semantic error prioritization, an efficient hardware algorithm for face tracking is proposed. The increase of hardware complexity is minimal because a motion estimation engine is efficiently re‐used for face tracking. Experimental results demonstrate that the facial area is well protected with the proposed scheme.     

岩屑泊松比实验测定仪

针对目前地层泊松比测定方法的局限 ,提出了利用上返岩屑压实测定地层泊松比的设想 ,并研制出岩屑泊松比实验测定仪。某油田已有的压实岩屑泊松比与实际声波测井资料计算泊松比对比发现 ,运用岩屑泊松比实验测定仪所得的实验结果与原始地层的泊松比有很好的一致性(两者的误差在± 5 %之间 )。利用该测定仪 ,可实现对钻井过程中上返岩屑的连续快速测定 ,大大降低工程取心所增加的钻井成本 ,还可为钻井施工在第一时间提供相关的地层信息     

Quality assessment of SRTM C- and X-band interferometric data: Implications for the retrieval of vegetation canopy height

The Shuttle Radar Topography Mission distinguished itself as the first near-global spaceborne mission to demonstrate direct sensitivity to vertical vegetation structure. Whether this sensitivity is viewed as exploitable signal or unwanted bias, a great deal of interest exists in retrieving vegetation canopy height information from the SRTM data. This study presents a comprehensive application-specific assessment of SRTM data quality, focusing on the characterization and mitigation of two primary sources of relative vertical error: uncompensated Shuttle mast motion and random phase noise. The assessment spans four test sites located in the upper Midwestern United States and examines the dependence of data quality on both frequency, i.e., C-band vs. X-band, and the number of acquired datatakes. The results indicate that the quality of SRTM data may be higher than previously thought. Novel mitigation strategies include a knowledge-based approach to sample averaging, which has the potential to reduce phase noise error by 43 to 80%. The strategies presented here are being implemented as part of an ongoing effort to produce regional- to continental-scale estimates of vegetation canopy height within the conterminous U.S.