摘要：An improved design method of pervious concrete was proposed to lower the deviation between the designed and actual porosity and maintain both mechanical property and permeability of pervious concrete. The improved design method is mainly based on the optimal volume ratio of paste to aggregate(VRPA), which was determined by testing the average thickness of cement paste coating aggregate. The performances of pervious concrete designed by the traditional method and the improved one were compared. The results show that with the increase of designed porosity, the reduction of compressive strength and flexural strength of pervious concrete designed by the improved method is significantly smaller than those designed by the traditional one. The maximum deviation between the designed and actual porosity of the pervious concrete by the improved method is only 1.54%, which is far less than 8.7% obtained by the traditional one. Micro-structural analysis shows that the porous distribution of pervious concrete designed by improved method exhibits better uniformity.

摘要：Non-pillar mining technology with automatically formed roadway is a new mining method without coal pillar reservation and roadway *** stability control of automatically formed roadway is the key to the successful application of the new *** order to realize the stability control of the roadway surrounding rock,the mechanical model of the roof and rib support structure is established,and the influence mechanism of the automatically formed roadway parameters on the compound force is *** this basis,the roof and rib support structure technology of confined lightweight concrete is proposed,and its mechanical tests under different eccentricity are carried *** results show that the bearing capacity of confined lightweight concrete specimens is basically the same as that of ordinary confined concrete *** bearing capacity of confined lightweight concrete specimens under different eccentricities is 1.95 times higher than those of U-shaped steel *** comparing the test results with the theoretical calculated results of the confined concrete,the calculation method of the bearing capacity for the confined lightweight concrete structure is *** design method of confined lightweight concrete support structure is established,and is successfully applied in the extra-large mine,Ningtiaota Coal Mine,China.

摘要：针对实际场景中动态物体、场景纹理、相机曝光等诸多影响,深度图提取结果广泛存在细节模糊和丢失等问题,同时因基于深度学习的网络没有传统算法中的捆集优化策略,无法对相机累积的误差进行分摊,这些都影响着深度图的精度.因此本文提出一种融合空洞卷积的DispNet深度网络,同时加入误差分摊策略给网络更强的约束条件.在DispNet的结构设计中,模型中加入空洞卷积设计新的卷积模块,使其扩大感受野,更多的提取上下文信息;模型中引入误差分摊损失函数减少相机误差的累积,以此提高相机位姿估计精度,得到高质量的重建视图;视频帧输入网络前先进行限制对比度直方图均衡化运算再输入模型.本研究在公开数据集KITTI上设计了实验,结果表明空洞卷积和误差分摊损失函数的引入对深度图恢复精度有明显的提升效果.

摘要：城市公交电动化可以有效缓解燃油车带来的空气污染和对化石能源的依赖,是公交行业发展的必然趋势。为此,将电动公交车队置换与充电设施布局进行统筹优化,以公交车队全生命周期成本和充电设施布局成本之和最小化为目标,基于时间和空间维度,构建电动公交车队置换与充电设施布局协同优化模型。根据模型特点,通过等价线性变换,将协同优化模型转换为混合整数线性规划模型。为验证协同优化模型的有效性,以江苏省江阴市公交网络为例,设计不同参数值情形下的数值试验。研究结果表明:在本案例参数设置下,协同优化决策获得的公交车队置换方案和充电设施布局方案比单独优化方案的总成本减少467 044.3元,具有较好的成本效益。在预算有限且排放限制要求不严格的情况下,公交运营商通常会购买更有价格优势的燃油公交车。随着电池技术的进步,电动公交车的采购价格有望下降,公交运营商会逐渐减少燃油车和混合动力车的购买,转而选择更环保的电动公交车。此外,公交车队的电动化进程需要与充电设施的建设相协调匹配,确保充电设施能够满足电动公交车的充电需求。政府可以通过增加CO_(2)的社会成本,促使运营商加速公交车队的电动化进程。研究成果为城市公交车队运营管理和充电基础设施建设提供了决策支持,为推进城市公交电动化进程提供了政策建议。

摘要：本文根据神经网络本身的错误弹性和层内过滤器相似性提出了一种近似容错设计,把过滤器划分成不同校验组进行不精确校验,保证严重错误被检出并恢复。通过优化过滤器-计算单元映射使校验流程与脉动阵列数据流契合,相较于传统双模冗余,本文提出的容错设计可以降低73.39%的性能开销。

摘要：针对传统单斜式模数转换器(Analog-to-Digital Converter,ADC)和串行两步式ADC在面向大面阵CMOS(Complementary Metal Oxide Semiconductor)图像传感器读出过程中的速度瓶颈问题,本文提出了一种用于高速CMOS图像传感器的全并行ADC设计方法.该方法基于时间共享和时间压缩思想,将细量化时间提前到粗量化时间段内,解决了传统方法的时间冗余问题;同时采用插入式时间差值TDC(Time-to-Digital Converter),实现了全局低频时钟下的快速转换机制.本文基于55-nm 1P4M CMOS工艺对所提方法完成了详细电路设计和全面测试验证,在模拟电压3.3 V,数字电压1.2 V,时钟频率250 MHz,输入电压1.2~2.7 V的情况下,将行时间压缩至825 ns,ADC的微分非线性和积分非线性分别为+0.6/-0.6LSB和+1.6/-1.2LSB,信噪失真比(Signal-to-Noise-and-DistortionRatio,SNDR)为68.271 dB,有效位数(Effective Numbers Of Bits,ENOB)达到11.0489 bit,列不一致性低于0.05%.相比现有的先进ADC,本文提出的方法在保证低功耗、高精度的同时,ADC转换速率提高了87.1%以上,为高速高精度CMOS图像传感器的读出与量化提供了一定的理论支撑.

摘要：目的通过微流控法制备载卵母细胞海藻酸钠微球,在低浓度保护剂下实现卵母细胞玻璃化保存。方法采用流动聚焦型微流控芯片,通过调整芯片结构、海藻酸钠溶液浓度和流速比,制备大小均匀、空包率低、低温耐受的载卵母细胞海藻酸钠水凝胶微球。在低浓度低温保护剂下将微球玻璃化保存,复温后检测存活率,采用细胞松弛素B和氯化锶孤雌激活卵母细胞,与Cryotop玻璃化法对比卵母细胞存活率和卵裂率、囊胚率。结果制备的海藻酸钠微球在冷冻复温前后的体积稳定且结构完整,在将卵母细胞包封在海藻酸钠水凝胶中后,空包率低,存活率、卵裂率和囊胚率与新鲜组相比无显著差异。在低浓度低温保护剂10%DMSO+10%乙二醇(EG)+0.5 mol/L海藻糖中玻璃化冻存后卵母细胞的存活率达到92.48%,卵裂率70.80%,囊胚率20.42%,与高浓度保护剂15%DMSO+15%EG+0.5 mol/L海藻糖中Cryotop玻璃化法相比无显著性差异。结论本文设计制作了三通道内部交联芯片并用于卵母细胞玻璃化保存的微流控系统,可生成大小均匀、空包率低、低温耐受的载卵母细胞海藻酸钠水凝胶微球,在低浓度保护剂下实现玻璃化保存,为卵母细胞玻璃化保存方法提供新思路。

摘要：被动柔性防护网是一种常见的落石灾害防治措施。针对当前落石被动柔性防护网尚无适用的工程化设计方法的现状,以非线性计算过程中结构内能与设计防护能级相等作为加载完成的判别准则,建立了落石被动柔性防护网的非线性静力设计方法。基于LS-DYNA对250~5000 kJ共8种常用能级的被动柔性防护网开展非线性动力分析,明确了冲击力的分布范围及相对大小,形成了适用于不同能级落石被动柔性防护网非线性静力设计的荷载模式。为了有效模拟被动柔性防护网特殊的受力特征,开发了由索单元与受拉弹簧单元组成的非线性耗能单元用于耗能器模拟,开发了内部由多段索单元组成的滑移索单元用于滑移边界以及网环单元模拟。基于对网片冲击试验的反演和3500 kJ被动柔性防护网的设计及足尺冲击试验检验,验证了所提出的落石被动柔性防护网非线性静力设计方法的有效性。

摘要：介绍了配电网远程事故呼叫系统的设计与实现过程。并详细讨论了语音处理程序软件设计的要点，ＯＤＢＣ访问数据库技术及进程间通信技术ＤＤＥ。

摘要：作为飞机防火系统的重要组成部分,机载灭火系统管网因其恶劣的工作环境、短时间内实现全淹没灭火的高性能要求以及尽可能小的装置重量而成为飞机火灾工程领域的重难点研究对象。为设计出高效的机载灭火系统管网,对机载灭火系统管网的结构、机制及输运动态进行了详尽分析,对影响灭火剂输运释放的设计要素与优化方法进行了分类综述,并总结了优化设计机载灭火系统管网的关键要点,指出将计算流体力学(CFD)与实验相结合的方式,是当前兼具可靠性与经济性的主流设计方法,为机载灭火系统管网未来的设计趋势与深入研究提供一定的参考。