摘要：When the variable geometry hypersonic inlet is sealed with ceramic wafers,the cavity flows inside the sealing chamber can be affected by the boundary layer near the side *** study the influence of the boundary layer thickness near the side wall on the flow and leakage characteristics in sealing chamber,the numerical calculation of the cavity flow in the sealing chamber under different inflow boundary layer thicknesses is carried *** results show that three-dimensional cavity flow structures are close to being asymmetric,and the entrance pressure of the leakage path can also be affected by asymmetry;with the increase of the thickness of the boundary layer,the pressure at the cavity floor and the seal entrance ***,the existing leakage prediction model is modified according to the distribution rule of the cavity floor and the flow properties in the leakage path.

摘要：报表生成功能是管理信息系统(MIS)中必不可少的、重要的组成部分。该文针对MIS中报表的特点与共性,研制开发了一个高度通用的、可继承的报表窗口类,该窗口具有通用性强、使用方便等特点。

摘要：阐述信息化对铁路现代化的重要意义,介绍广深线路和运输作业的复杂性,以及广深线CTC系统的主要功能。针对广深线CTC系统功能创新,进行详细的分析。最后,总结和讨论CTC系统的应用前景。

摘要：We demonstrate a simple and controllable way to synthesize large-area, few-layer graphene on iron substrates by an optimized chemical vapor deposition （CVD） method using a mixture of methane and hydrogen. Based on an analysis of the Fe-C phase diagram, a suitable procedure for the successful synthesis of graphene on Fe surfaces was designed. An appropriate temperature and cooling process were found to be very important in the synthesis of highly crystalline few-layer graphene. Graphene-based field-effect transistor （FET） devices were fabricated using the resulting few-layer graphene, and showed good quality with extracted mobilities of 300-1150 cm2/（V.s）.

摘要：以热光型器件的热学模型和温度场解析表达式为基础,运用射线法,通过计算位于芯区不同子午面内的光线反射轨迹,对热光效应下光束经全内反射后展宽的原因和规律进行了分析,并且给出了具体光束展宽值的理论计算方法;设计了高反射率的全内反射型有机聚合物热光开关。在设计中应用所提出的规律,理论上计算出了具体的展宽波导宽度、芯区的掩埋深度、扩大的反射区宽度等结构参量。软件的模拟结果表明,该结构在反射态和直通态时的效率分别为82.6%和84.4%,串扰均大于30dB,并且对这些结构参量的模拟优化结果与理论计算结果基本一致。

摘要：根据昆虫扑翼飞行节律运动的原理,设计一个压电驱动的两自由度扑翼机构。在建立扑翼物理模型的基础上,研究了其模态特征,并结合主动控制构建了一个范德波尔(van derPol)类型的自激振动扑翼系统,使扑翼产生稳定的极限环运动。通过研究系统的响应,分析了控制力中各参数变化对系统特性的影响。在此基础上,利用交叉反馈选择出系统的第一阶模态振动,并调节各参数使扑翼飞行器实现不同的飞行模式。

摘要：针对现有谣言检测方法在微调大语言模型时导致的高内存占用,以及提示学习方法对初始点选择敏感的问题,提出一种基于元多任务提示学习的零样本谣言检测方法。首先,基于提示学习范式调整零样本谣言检测任务目标,通过设计提示模板使这一任务目标与大语言模型的训练任务目标保持一致,以充分利用大语言模型积累的先验知识。其次,利用元学习的参数更新策略以定位适用于零样本谣言检测任务的提示模板初始点,从不同的元任务中学习通用知识来实现参数优化。最后,引入情感分析作为辅助元任务进一步调整和优化模型参数。在多个公开数据集上的对比实验结果表明,所提方法在零样本谣言检测任务中表现出色,其性能指标优于基准方法。

摘要：The development of a high performance wideband radio frequency （RF） transceiver used in the next generation mobile communication system is presented. The developed RF transceiver operates in the 6 to 6.3 GHz band and the channel bandwidth is up to 100 MHz. It operates in the time division duplex （TDD） mode and supports the multiple-input multipleoutput （MIMO） technique for the international mobile telecommunications （IMT）-advanced systems. The classical superheterodyne scheme is employed to achieve optimal performance. Design issues of the essential components such as low noise amplifier, power amplifier and local oscillators are described in detail. Measurement results show that the maximum linear output power of the RF transceiver is above 23 dBm, and the gain and noise figure of the low noise amplifier is around 24 dB and below 1 dB, respectively. Furthermore, the error vector magnitude （EVM） measurement shows that the performance of the developed RF transceiver is well beyond the requirements of the long term evolution （LTE）-advanced system. With up to 8 x 8 MIMO configuration, the RF transceiver supports more than a 1 Gbit/s data rate in field tests.

摘要：设计了一种新型的广义圆锥倒角V型柔性铰链,铰链切口由圆锥曲线及其切线构成,铰链具体类型包括抛物线倒角V型、椭圆倒角V型、双曲线倒角V型、抛物线型、椭圆弧型、双曲线型和直梁型。以极角θ作为变量推导此类柔性铰链的柔度方程。通过有限元分析和实验研究验证了理论模型的正确性和有效性。分析了设计参数对柔性铰链柔度的影响规律,结果表明:柔度因子随着设计参数e(离心率)和p(焦点与准线间的距离)的增大而增大,随着设计参数φ(切线部分与x轴夹角)、t(切口部分最小厚度)和w(铰链宽度)的增大而减小;在设计参数e、p、t和w相同的情况下,圆锥倒角V型柔性铰链比传统圆锥曲线型柔性铰链具有更高的柔度。

摘要：本文设计了一种新的具有可变节流面积的空气静压气浮支承并建立了气浮支承CFD模型,基于标准的k-ε湍流模型,借助仿真模拟分析了径向狭缝高度(Hb)、轴向狭缝宽度(Hn)、均压腔深度(Hf)和供气压力(Ps)对气浮支承静态性能的影响。根据刚度优先的设计原则,兼顾承载力,确定了较理想的参数取值范围。