基于修正线粗糙度法的岩石节理粗糙度估值

考虑了节理形态的层次性,提出了用修正的线粗糙度法表征节理轮廓线粗糙度（JRC）,即用节理轮廓线的起伏度表示节理的一级波状形态,用伸长率代表节理的次级精细结构。通过对Barton给出的10条典型节理轮廓线的特征参数计算,并与相应的JRC值进行回归分析,给出了JRC值计算公式。另外,要获得节理轮廓线的伸长率,节理全迹长是一个很重要的参数。在工程实践中,针对全迹长量测存在的困难,研究以摄影测量为基础,借助数字图像处理技术,在VC⁺⁺平台下开发了节理轮廓线特征参数计算程序,实现了节理全迹长的快速量测,并对该方法在工程实践中的方便应用做了有益的探索。     

面向石化企业间物流集成计划优化的模型及应用

在石油化工行业,上下游企业的联合生产是供应链优化的主要途径和重要手段。但由于石化企业的生产工艺过程复杂且设计相互独立,企业间的协同生产往往仅存在于大型石化集团统一设计、建造的炼化联合生产系统中。本文提出了适用于独立运营的石化企业集成的前提条件和建模方法,以独立生产的炼油厂和烯烃厂为研究对象,基于其生产物流计划模型,建立统一的联合生产计划优化模型。该集成优化模型为混合整数线性规划模型,以生产效益最大化作为优化求解目标,并分析了市场需求平稳、萎缩和旺盛3种不同的案例场景。实例计算表明,同独立生产相比较,石化企业的集成优化和联合生产能够降低物料存储成本和总成本,节省优化求解所需的计算资源,并促进经济效益的提升。     

机械手在制药生产线上的应用

介绍了机械手的设计方案和特点,对单片机最小系统模块、电源模块、时钟与复位模块、开关与键盘模块、显示模块和驱动模块进行了详细的阐述,同时说明了机械手在制药生产线上的实际应用,满足了制药企业的需求。     

Ⅱ类水体光学分类方法研究进展

鉴于Ⅱ类水体本身光学性质的复杂性及其与人类生产活动的密切关系,对其进行光学分类以提高水色参数反演精度和监测Ⅱ类水体水质有着重要意义.本文对近年来使用的Ⅱ类水体光学分类方法进行了归纳和评价,主要有:基于光谱形状的水体分类法;监督分类法;聚类分析法;多波段比值法.针对目前分类方法存在的问题,提出未来的研究需要加强对光谱反射...     

降混剂对二氧化碳在稠油中的溶解度和最小混相压力的影响

针对CO₂ 驱油过程中,稠油体系与CO₂ 难混相,最小混相压力高于地层破裂压力的问题,对CO₂ 与原油的混合体系进行了分子模拟,考察了降混剂种类和加量、温度、压力的影响。由径向分布函数得到混相过程中CO₂ 分 子及沥青质分子的聚集程度,进而明确各类分子的分散状态,分析其作用机理。在此基础上,开展高温高压PVT 相态实验,测定CO₂ 与原油混合体系中添加不同降混剂后的体积膨胀系数和CO₂ 溶解度,对分子模拟结果进行验证。最后,对柠檬酸三甲酯、苯甲醇、苯甲酸乙酯3种降混剂进行优选,得到最优复配配方,并通过细管实验评价其降混性能。分子模拟结果表明,柠檬酸三甲酯的降混效果最为显著,可有效增大CO₂ 分子间的聚集程度,降低 沥青质分子间的聚集程度;在高压（6.90MPa）低温（308.15K）的条件下,降混剂更能发挥其作用。PVT相态实验 结果表明,0.23%柠檬酸三甲酯的增溶与增膨作用最佳,与分子模拟结果一致。降混剂最优复配配方为80%柠檬 酸三甲酯+20%苯甲酸乙酯。在原油-CO₂ 体系中加入0.23%复配降混剂,最小混相压力降幅为21.47%,CO₂ 溶解 度和原油采收率提高。降混剂含有亲油的烃类基团和亲CO₂ 的酯基,不仅能与原油体系中的极性分子结合,拆散各沥青分子的聚集体,同时在双亲性能作用下,能吸附在原油与CO₂ 的界面上,降低原油与CO₂ 的界面张力,进而降低最小混相压力。     

基于时空上下文模型的RGB-D序列目标跟踪方法

为了实现更为精确的视频目标跟踪,提出一种以时空上下文模型为基础的RGB-D序列目标跟踪算法.通过引入更新模板的深度信息,该模型精准地区分了输入序列的目标区域与背景区域,实现了深度权值和颜色权值的融合;基于目标序列的深度及目标动量计算,该模型有效地实现了尺度更新与遮挡处理.通过在RGB-D图像序列数据集上的详细实验评估,该时空上下文模型相对于其他先进的同类方法表现出更好的性能.因此,该方法实现了更为精确可靠的视频目标跟踪.     

时频电磁(TFEM)技术:数据采集参数设计

时频电磁法（TFEM）是一种应用于油气勘探领域、探测深度较大的可控源电磁方法。本文以Q地区探测目标地层为模型,基于探区噪声分析,对地质目标进行三维模拟,分析目标体电磁异常特征及规律,并对TFEM采集参数的设计进行了研究与分析。提出了等腰梯形区域测网布设、测点信号平衡的接收系统设计方法,以及基于目标异常对比分析的发射系统优化设计,同时提出针对目标的激发周期和叠加次数设置的激发参数设计方法,为TFEM勘探采集设计提供科学的借鉴和参考。     

Solid-state transformer-based new traction drive system and control

A new type of traction drive system consisting of solid-state traction transformer (SSTT), inverter unit, auxiliary inverter, traction motor and other key components is built in order to suit the demand of developing the next-generation electric traction system which will be efficient and lightweight, with high power density. For the purpose of reducing system volume and weight and improving efficiency and grid-side power quality, an efficient SSTT optimized topology combining high-voltage cascaded rectifiers with high-power high-frequency LLC resonant converter is proposed. On this basis, an integrated control strategy built upon synchronous rotating reference frame is presented to achieve unified control over fundamental active, reactive and harmonic components. The carrier-interleaving phase shift modulation strategy is proposed to improve the harmonic performance of cascaded rectifiers. In view of the secondary pulsating existing in a single-phase system, the mathematical model of secondary power transfer is built, and the mechanism of pulsating voltage resulting in beat frequency of LLC resonant converter is revealed, so as to design optimum matching of system parameters. Simulation and experimental results have verified that the traction system and control scheme mentioned in this paper are reasonable and superior and that they meet the future application requirements for rail transit.     

Numerical Investigation on the Vortex-Flow Characteristics in Rod Bundles with Mixing-Vane Spacer Grids

In nuclear reactor fuel assemblies, spacer grids are installed among the rod bundles to support the fuel rods and affect the flow field between rods. Mixing vanes, as a swirling device, are set on the upper apex of the spacer grid. Vortexes produced by mixing vanes move along the axial direction in subchannels and enhance the forced convection heat transfer between the rods and cooling-fluid medium. In this paper, a numerical simulation method was used to investigate vortex motion produced by typical AFA-3G spacer grids in a 5×5-rod bundle by Star-CCM+ software. The shear-stress transport k-ω model was used to simulate turbulence phenomena. A dimensionless parameter, Se, based on the absolute vorticity flux, was reported to specify the intensity of secondary flow. Its physical meaning is the ratio of inertial force to viscous force induced by secondary flow. The results are helpful to take advantage of spacer grids in a much more effective way in pressurized water reactors.     

A Contact-Sliding-Triboelectrification-Driven Dynamic Optical Transmittance Modulator for Self-Powered Information Covering and Selective Visualization

Triboelectrification-enabled self-powered flexible electronic/optical systems have aroused a new surge of interest in recent years. All-in-one integration of such a system, which could significantly improve its adaptability, operability, and portability, still remains a challenge due to the absence of suitable architectures and integration schemes. Herein, a previously reported self-powered optical switch (OS) is thoroughly remolded and upgraded to a fully integrated contact-sliding-triboelectrification-driven dynamic optical transmittance modulator (OTM). The OTM is constructed with a multilayered structure, comprising a transparent triboelectrification top layer, a SiO₂-spaced polymer dispersed liquid crystal (PDLC) intermediate layer, and a flexible transparent conductive substrate. The working mechanism is that an alternating electric field can be induced once contact-sliding occurs upon the OTM, rendering the PDLC layer immediately switching its initial translucent state to an instantaneous transparent state. As such, a decent dimming range with the relative transmitted light intensity from 0.17 to 0.72 can be achieved at low mechanical thresholds of contact pressure (≈20 kPa) and sliding velocity (≈0.3 m s⁻¹). Moreover, for practical applications, demonstrations of information covering and selective visualization are successfully implemented without any extra optical elements nor external power supplies, explicitly showing great potential for the OTM in various self-powered optical interactive applications.