三维叠前深度偏移处理技巧与应用

结合研究区的地质资料，着重就研究区的速度深度模型的人工控制进行了研究；基于研究区断裂系统复杂，为了解所用处理方法对复杂构造的适用性，设计了2个模型来检验叠前深度偏移效果的有效性；与时间偏移相比，叠前深度偏移高质量地解决了复杂断块区的成像问题。     

The Synthesis of Sulfated Titanium Oxide Nanotubes

TiO₂ nanotubes can be prepared in gram quantities by treating anatase TiO₂ powder with concentrated NaOH solution. These TiO₂ nanotubes acquired strong acidity after being impregnated with sulfuric acid solution and calcined at 300 °C. The anatase TiO₂ powder used to prepare the nanotube did not catalyze the esterification between cyclohexanol and acetic acid, while sulfated TiO₂ nanotubes were very reactive toward the esterification reaction.     

用于机器人轨迹定位纠正系统的回声状态神经网络研究

循环神经网络(RecurrentNeuralNetworks)是人工神经网络(ArtificialNeuralNetworks)中重要的分支,与前馈神经网络(ForwardNeuralNetworks)相比具有更好的时间序列学习能力。但长期以来其学习法一直不能脱离前馈神经网络而自成一体,回声状态神经网络(EchoStateNetworks(ESN))是打破这一局面的全新学习方法。其独特的结构,良好的短期记忆能力,方便的学习方法,不俗的非线性特性是以前循环神经网络所不可比的。本文在介绍了回声状态神经网络之后将其用于四轮机器人的位置测量系统中,有良好的表现。     

兰州重离子加速器大型真空室

已建成的兰州重离子加速器的真空室是一个大型整体结构的超高真空容器,直径约10m,高4.5m,重65000kg,内表面积211m~2,容积100m~3,工作真空度为5×10~(-5)Pa。采用有限单元法在计算机上用SAP-5C程序对真空室受力分析进行了计算。真空室结构材料选用瑞典Uddeholm钢厂生产的316 L 超低碳不锈钢。承制此大型容器的是航天工业部风华机器厂。由于结构庞大,首先将真空室分成八大块和几小块在工厂制造,然后运至现场焊制成一整体容器并进行机械加工。所有密封焊缝均用着色渗透液,X-射线探伤和氦质谱探漏仪进行检查和探漏。     

Fabrication of multi-walled carbon nanotube reinforced polyelectrolyte hollow nanofibers by electrospinning

Hybrid hollow multi-walled carbon nanotubes (MWCNTs)/polyelectrolytes (PE) nanofibers were prepared by a combination of the electrospinning method and layer-by-layer (LbL) technique. The mixed polystyrene (PS)/MWCNTs nanofibers were obtained by electrospinning method, which were employed as templates to self-assembly multilayered polyelectrolytes by LbL technique. Hollow MWCNTs/PE nanofibers were obtained by selectively removed part of the template: PS, which is confirmed by Raman spectra, transmission electron microscopy (TEM) and scanning electron microscopy (SEM).     

现代数值计算与模拟技术在大学物理中的应用

讨论了现代数值计算与模拟技术在大学物理中的应用，并给出了两个具体应用的实例．     

Dynamic bandwidth allocation for multimedia traffic with rate guarantee and fair access in WCDMA systems

Packet scheduling in a WCDMA system poses a new challenge due to its nature of variable bit rates and location-dependent, time-varying channel conditions. In this work, three new downlink scheduling algorithms for a WCDMA base station are proposed to support multimedia transmissions. Using a credit management and a compensation mechanism, our algorithms provide rate guarantee and fair access to mobile terminals. In particular, we propose to allow a user to simultaneously use multiple OVSF codes in a time-sharing manner, which we call a multicode, shared model. Using multiple codes allows us to compensate those users suffering from bad communication quality or even errors. The proposed schemes can tolerate a multistate link condition (compared to the typically assumed two-state, or good-or-bad, link condition) by adjusting the number of OVSF codes and the spreading factor of each code. Simulation results show that the proposed schemes do achieve higher bandwidth utilization while keeping transmission delay low.     

3Cr-3Mo二次硬化钢的回火组织和力学性能

研究了3cr—3Mo二次硬化钢淬火回火后的组织和力学性能。结果表明：随回火温度的升高，试验钢中先后析出M3c、M2c和M7C3等碳化物，在575℃回火时硬度达到峰值；400一575℃回火后试验钢的抗拉强度约为l600MPa，冲击韧性为30J／cm^2；回火温度高于600℃时，强度和硬度迅速下降，冲击韧性增加；640℃回火时，以M2C型碳化物为主，抗拉强度为1100MPa，冲击韧性增加至55J／cm^2。     

卧式厚箔剪切机下刀摆动的消除方法

介绍了一种当前铝加工设备中常见的卧式厚箔剪切机.重点分析了其中剪切装置的工作原理,并就其缺陷提出改进方案.     

延长测井电缆使用寿命的方法探讨

由于对测井电缆机械性能缺乏了解,使用不规范,使测井电缆使用寿命降低.通过对测井电缆结构、制造工艺进行分析,进一步掌握其性能,提出通过正确安装、使用前需进行稳定化处理、在使用中注意控制起下速度、日常清洁润滑、定期对电缆进行维护保养等方法维持铠装层正常状态,减少层间摩擦力,不扭曲,缆芯通断良好等方法,从而延长电缆的使用寿命.