摘要：单通道包含的信息非常有限使得单通道语音分离是一个非常具有挑战性的研究领域。文中提出一种基于深度神经网络(DNN)的监督学习算法,将混合语音信号从单通道中分离出来。首先,将原始信号混合并提取特征,输入到分离网络中输出分离后的信号。通过设计实验,对网络的最佳参数进行选择,并确定特征向量和上下文窗口大小。最后采用TIMIT语料库来评估提出的算法,与基于非负矩阵分解(NMF)的模型相比,基于DNN的模型在SDR指标上提高了1.67d B。

摘要：Synthetic polymer hydrogel nanoparticles(NPs)were developed to function as abiotic affinity reagents for *** NPs were made using both temperature-sensitive N-isopropyl acrylamide(NIPAm)and L-amino acid *** kinds of L-amino acids were acryloylated to obtain functional monomers:L-phenylalanine(Phe)and L-leucine(Leu)with hydrophobic side chains,L-glutamic acid(Glu)with negative charges,and L-lysine(Lys)and L-arginine(Arg)with positive *** incubating the NPs with fibrinogen,g-globulin,and human serum albumin(HSA)respectively,the NPs that incorporated Nacryloyl-Arg monomers(AArg@NPs)showed the strongest and most specific binding affinity to fibrinogen,when compared with g-globulin and ***,the fibrinogen-AArg binding model had the best docking scores,and this may be due to the interaction of positively charged AArg@NPs and the negatively charged fibrinogen D domain and the hydrophobic interaction between *** specific adsorption of AArg@NPs to fibrinogen was also confirmed by the immunoprecipitation assay,as the AArg@NPs selectively trapped the fibrinogen from a human plasma protein ***@NPs had a strong selectivity for,and specificity to,fibrinogen and may be developed as a potential human fibrinogen-specific affinity reagent.

摘要：The concept of“robust dynamics”describes the incorporation of mechanically interlocked molecules(MIMs)into metal-organic framework(MOF)materials such that large amplitude motions(e.g.,rotation or translation of a macrocycle)can occur inside the free volume pore of the *** aid in the preparation of such materials,reticular synthesis was used herein to design rigid molecular building blocks with predetermined ordered structures starting from the well-known MOF *** linkers were synthesized that have a T-shape,based on a triphenylene tetra-carboxylate strut,and their incorporation into Cu(II)-based MOFs was *** single-crystal structures of three new MOFs,UWCM-12(fof),β-UWCM-13(loz),UWCM-14(lil),with naked T-shaped linkers were determined;β-UWCM-13 is the first reported example of the loz topology.A fourth MOF,UWDM-14(lil)is analogous to UWCM-14(lil)but contains a[2]rotaxane ***-temperature,^(2)H solid-state NMR was used to probe the dynamics of a 24-membered macrocycle threaded onto the MOF skeleton.

摘要：Breaching of embankments has recently drawn more and more attention due to its importance in the development of early warning systems for embankment failures,in the evacuation plans of people at risk,in the design method of embankments based on a risk-approach,etc. The erosion process observed during embankment breaching tests in the laboratory and the analysis of the results are described in this paper. Five embankments,one constructed with pure sand,four with different sand-silt-clay mixtures were tested. The height of the embankments was 75 cm and the width at the crest was 60 cm. Examination of the data from these tests indicated that headcut erosion played an important role in the process of breach growth in the embankments made of cohesive soil mixtures. Flow shear erosion,fluidization of the headcut slope surface,undermining of the headcut due to impinging jet scour and discrete soil mechanical slope mass failure from the headcut were all observed during these tests. For the embankment constructed with pure sand,the breach erosion process was dominated by shear erosion,which led to a gradual and relatively uniform retreat of the downstream slope. The cohesive proportion in the sand-silt-clay mixtures strongly slowed down the erosion process.

摘要：针对可重构生产系统不足以支持面向产品的交钥匙生产系统的快速构建,特别是尚未形成公认的标准及认证应用范例的现状,基于工业4.0参考架构模型(RAMI 4.0)设计能实现系统快速构建的交钥匙工程的信息参考体系架构。结合数字孪生、第五代移动通信技术(5G)、OPC统一架构(OPC UA)等信息技术,从信息视图的角度建立以可重构生产系统为核心的交钥匙工程的信息参考体系架构,以及系统配置与重构平台、数字孪生平台等关键使能工具,为设计与生产的信息交互、不同层级之间的通信、系统的快速构建与验证等提供参考解决方案,并以某阀体类零件的交钥匙工程为例进行了实例验证。

摘要：为了准确地获取矿井瓦斯/空气预混气体爆燃流场的内部微观结构信息,能够从基元反应层面认识爆燃流场的演化过程以及惰性介质阻燃剂抑制作用的机理,在已经建成的中尺度激波管道上继续搭建高速激光纹影测试系统,结合实验室几何空间约束条件,提出纹影测试系统'Z'字型光路的设计方案。以激光纹影系统代替传统的压力火焰测试系统,将爆燃流场的研究重心从宏观的单一点源信息向微观的多重结构信息转化。研究表明,在60,100,125,212ms时火焰阵面的化学反应变强,伴随着产生了冲击波,在75ms左右火焰发生断裂,该点处的压力下降,325ms火焰阵面扫过该测点以后,压力迅速下降。该结果为寻求预混气体爆燃高速摄影、压力火焰速度测试手段之外的方法提供了新的研究思路。

摘要：Wastewater treatment is a process that is vital to protecting both the environment and human health. At present, the most cost-effective way of treating wastewater is with biological treatment processes such as the activated sludge process, despite their long operating times. However, population increases have created a demand for more efficient means of wastewater treatment, Fluidization has been demonstrated to in- crease the efficiency of many processes in chemical and biochemical engineering, but it has not been widely used in large-scale wastewater treatment. At the University of Western Ontario, the circulating fluidized-bed bioreactor （CFBBR） was developed for treating wastewater. In this process, carrier particles develop a biofilm composed of bacteria and other microbes. The excellent mixing and mass transfer characteristics inherent to fluidization make this process very effective at treating both municipal and industrial wastewater. Studies of lab- and pilot-scale systems showed that the CFBBR can remove over 90% of the influent organic matter and 80% of the nitrogen, and produces less than one-third as much biological sludge as the activated sludge process. Due to its high efficiency, the CFBBR can also be used to treat wastewaters with high organic solid concentrations, which are more difficult to treat with conventional methods because they require longer residence times; the CFBBR can also be used to reduce the system size and footprint. In addition, it is much better at handling and recovering from dynamic loadings （i.e., varying influent volume and concentrations） than current systems. Overall, the CFBBR has been shown to be a very effective means of treating wastewa- ter, and to be capable of treating larger volumes of wastewater using a smaller reactor volume and a shorter residence time. In addition, its compact design holds potential for more geographically localized and isolat- ed wastewater treatment systems.

摘要：目的:研发一种用于完全丧失或部分丧失运动功能的上肢进行被动运动康复治疗的持续被动运动机。方法:根据上肢生物运动力学特性,利用机械原理、机构与传动、电气控制的知识,完成持续被动运动机的结构设计、外形设计和电气控制设计。结果:完成了圆周转动型上肢持续被动运动机的设计。该持续被动运动机,在结构上把电机的转动通过变速、柔性传动变为摇臂的圆周转动运动,患者上肢在与摇臂相连托架的带动下,使上肢的手心位置随摇臂做圆周转动,从而带动整个上肢做持续被动运动。在电气控制上,可实现变速、定时的功能。该机转动半径200～300mm可调,转速30～100r/min可调。上肢的弯曲程度,通过人机之间的距离进行调节。患者可以坐式、仰卧式进行被动运动。结论:持续被动运动机可使患者上臂整体同时进行持续被动运动。由于设计了托架,比较适合上肢完全失去运动功能的患者。前臂相对固定在托架上,保证了完全失去运动功能的上肢在运动过程中,始终保证其生物运动力学特性。

摘要：在选区激光熔融成形过程中,飞溅与熔池包含了能够体现加工质量的重要特征信息,从成形过程采集到的熔池图像中,获得这些信息,实现选区激光熔融的过程监测是近年来研究的重点之一。为了更加精确且有效地从图像中提取熔池和飞溅的信息,提出了一种基于YOLOv5目标检测模型,实现了对成形过程图像中飞溅与熔池的实时定位与捕获。首先,以YOLOv5s目标检测网络为基础,调整骨干网络的深度与宽度,修改检测头的数量。之后,引入自校正卷积与CBAM注意力机制模块,设计了新的特征整合结构,通过上述步骤,提升了网络的检测性能。将工业相机采集到的图像制作为目标检测数据集,进行模型的训练与测试,结果表明该网络能够从原始图像中对飞溅与熔池目标进行准确的定位,在具有良好的检测精度的同时,网络模型的参数量极少,更加符合工业应用的需求。网络的检测精度mAP@0.5:0.95达到了0.466,为基于图像的选区激光熔融过程监测提供了一种新的方法。

摘要：疫苗的公共卫生意义在于疫苗的群体保护效应，即当疫苗接种率达到一定水平时，疫苗接种将会直接保护接种人群和间接保护未接种人群。扩大疫苗接种率达到足够的群体保护是预防甚至是根除某些传染性疾病的基本策略。此外，群体保护的评价在制定公共卫生策略方面具有十分重要的作用。近年来，国外关于疫苗群体保护的研究El益增多，包括人群观察性研究和群随机对照临床研究，但国内还未见相关的文献报道。本文旨在对评价疫苗群体保护的研究设计及方法进行阐述，为我国在该领域的相关研究提供参考。