经纬仪工业测量系统直接坐标传递后的点位坐标及精度分析

对经纬仪工业测量系统应用于亚毫米级的大型工件的测量 ,提出了一种快速坐标转换的方法。利用定向参数作为坐标转换参数 ,导出了在统一坐标系下点位坐标的计算公式 ,并对转换后的坐标进行了精度分析。     

应力波在平台-桩系统中传播的实验研究

分析了应力波在平台－桩系统中的传播图案。对有限尺寸的平台来说，应力波在平台边界面上会发生反射，反射波不仅有同类波同时还有转换波，除此之外，平台表面的响应还受桩及桩土相互作用的影响。除非桩身反射波走时较长，可以避开平台上的各种干扰波，否则，由平台实测波形特征来分析平台下桩的完整性是很困难的。通过对平台上完整桩实测波形与异常桩波形进行比较，可以提高波形识别的准确度，此外，根据桩侧面测点及平台表面测点走时，相位、幅值间关系，将两者信号进行比较，可以从复杂的信号中辨别出桩身反射波信号。     

Conversion of sedimentary fatty acids from extractable (unbound + bound) to tightly bound form during mild heating

Prolonged heating (1–248 days) of a recent sediment was conducted under mild conditions (65 and 83°C) to understand the thermal behavior of extractable (unbound and bound) fatty acids (C_12C32). In the course of the heating, the concentrations of saturated and monounsaturated fatty acids first decreased, and then increased. This indicates that extractable fatty acids can be converted to a tightly bound form upon heating, before fatty acids are extensively released from sediment matrices. Changes in molecular distributions of extractable fatty acids upon heating were also observed. The higher molecular weight fatty acids (?C₂₀) are more likely to become tightly bound than are lower molecular weight (<C₂₀). Monounsaturated fatty acids (C_16:1 and C_18:1) are more easily converted to the tightly bound form than polyunsaturated fatty acids (C_18:2 and C_18:3). These differences probably reflect their mode of occurrence in sediments, which are closely related to their origin.     

对里特曼岩石化学换算法的一些改进和补充

本文根据国内、外详细研究过的部分岩石,通过判别、回归分析,编制了选择计算相的S指令程序和蚀变风化岩恢复原岩成分的调整程序,以克服里特曼法对岩石含水情况估计的人为性等缺点。同时,编制了标准矿物子程序、校正程序及向量投影制图程序,使里特曼法能在微型计算机上实施,并实现成果绘图自动化,为该法的推广普及创造了条件。     

Verification studies for a z-coordinate primitive-equation model: Tidal conversion at a mid-ocean ridge

We document the accuracy and convergence of solutions for a z-coordinate primitive-equation model of internal tide generation and propagation. The model, which is based on MOM3 numerics, is linearized around a state of rest to facilitate comparison with analytic estimates of baroclinic generation at finite-amplitude topography in a channel forced by barotropic tidal flow at its boundaries. Unlike the analytical model, the numerical model includes mixing of both buoyancy and momentum, and several definitions of “baroclinic conversion” are possible. These are clarified by writing out the energetics of the linearized equations in terms of barotropic kinetic energy, baroclinic kinetic energy, and available potential energy. The tidal conversion computed from the model, defined as the rate of conversion of barotropic kinetic energy into available potential energy, agrees well with analytical predictions. A comparison of different treatments of bottom topography (full-cells, partial-cells, and ghost-cells) indicates that the partial-cell treatment is the most accurate in this application. Convergence studies of flow over a smooth supercritical ridge show that the dissipation along tidal characteristics is, apparently, an integrable singularity. When the ocean bottom is not smooth, the accuracy and convergence of the model depend on the power spectrum of the topography. A numerical experiment suggests that the power spectrum of the resolved topography must roll off faster than k⁻² to obtain convergent results from a linear numerical model of this type.     

船载海洋生态环境现场监测集成示范系统硬件平台设计

提出了利用快速以太网技术实现“船载海洋生态环境现场监测集成示范系统”硬件平台的设计方案 ,阐述了将船载设备集成于以太网协议转换器的软硬件设计与实现。协议转换器采用 Rabbit2 0 0 0微处理器及 Dynamic C语言开发 ,主要完成 RS2 32标准串口协议与 TCP/ IP协议之间的转换 ,利用协议转换器不但可以使原本不具备以太网接口的船载串行设备方便地联入到网络中 ,还可以延伸设备和主机之间的联接距离 ,并由此搭建船载集成系统的硬件平台。     

三轴不等应力场下剪切破裂趋势面方向探析

文章在弹性力学和库仑-摩尔破裂理论基础上,用数学解析方法剖析三轴不等应力状态,以及三轴全拉、三轴全压和最大最小主应力一拉一压三种情况下,斜截面上剪应力与抗剪阻力之差——"剪切差函数"的极值。进而探讨了剪切破裂趋势面方向与三主应力轴,及岩石(体)内摩擦角φ和内聚力C的关系。给出了不同应力状态下发生剪切破裂面的可能方向。在全压状态下,剪切破裂趋势面与最大主压应力轴夹角γ=±(45°-φ/2),即共轭角χ=±(90°-φ)。在一拉一压状态下,±(45°-φ/2)≤γ≤±45°,具体数值视拉主应力与压主应力比值确定。以上三种不等主应力下的剪切破裂面都是平面,且平行于中间主应力轴。构造拉张力的存在是无可争议事实,通过一拉一压状态下剪切破裂面趋势面分析,给出了构造地质实践中为什么有时剪切面共轭角χ>±(90°-φ),甚至接近90°的理论分析。     

深层致密砂岩储层脆性指数评价新方法

储层岩石脆性评价是储层压裂改造方案设计的重要基础工作,对储层压裂改造效果有着重要影响。以准中地区深层致密砂岩储层为研究对象,开展了0~90 MPa多级围压下的岩石三轴试验,分析了围压变化对于岩石脆性的影响。针对现有脆性指数对目标储层岩石脆性评价效果不理想的情况,基于应力-应变曲线中的能量转化关系建立了新的脆性指数模型,包括岩石峰前峰后脆性指数和综合脆性指数。研究结果表明:试验围压对岩石脆性评价有着显著影响;岩石峰前脆性随围压增大先增加后减小,峰后脆性和综合脆性随围压增大而递减;研究区储层含砾细砂岩的脆性较细砂岩的脆性小,脆性差异主要表现在峰后脆性。      

基于模糊信息优化理论的平面相似变换建模技术研究

运用模糊信息优化理论(信息扩散估计)导出各项模型精度估算指标.利用近似t-检验构造模型精度判研依据,以判断模型的可靠性.以小东江坐标系统变换为实例,演示、验证了建模技术的可操作性.     

在大气运动中考虑重力加速度空间变化的问题

给出了在旋转坐标系中考虑重力加速度g的空间变化的大气控制方程组,并证明了大气总质量和总能量的守恒性,以及和取常值g时得到的结果相一致的动、位能和动、内能之间的转换关系.还讨论了在球坐标系中应用方程组时可能出现的困难,给出了在高度近似下在该系中考虑g的空间变化的方案,它可以用来建立完全弹性的非静力模式.