Detection of crowdedness in bus compartments based on ResNet algorithm and video images

Multimedia Tools and Applications - The crowding in bus is an important factor affecting passenger satisfaction and bus dispatching level. However, how to use video images to detect crowding...     

Broad-Spectral-Range Sustainability and Controllable Excitation of Hyperbolic Phonon Polaritons in α-MoO3

Hyperbolic phonon polaritons (HPhPs) in orthorhombic-phase molybdenum trioxide (α-MoO₃) show in-plane hyperbolicity, great wavelength compression, and ultralong lifetime, therefore holding great potential in nanophotonic applications. However, its polaritonic response in the far-infrared (FIR) range remains unexplored due to challenges in experimental characterization. Here, monochromated electron energy loss spectroscopy (EELS) in a scanning transmission electron microscope (STEM) is used to probe HPhPs in α-MoO₃ in both mid-infrared (MIR) and FIR frequencies and correlate their behaviors with microstructures and orientations. It is found that low structural symmetry leads to various phonon modes and multiple Reststrahlen bands (RBs) over a broad spectral range (over 70 meV) and in different directions (55–63 meV and 119–125 meV along the b-axis, 68–106 meV along the c-axis, and 101–121 meV along the a-axis). These HPhPs can be selectively excited by controlling the direction of swift electrons. These findings provide new opportunities in nanophotonic and optoelectronic applications, such as directed light propagation, hyperlenses, and heat transfer.     

Numerical Investigation of the Capture of Polydisperse Particles by Charged Droplets

The capture of particles by charged droplets was simulated by considering the electrostatic interactions of droplet-droplet and droplet-particle. The results indicate that the electrostatic repulsion between droplets leads to a dynamic accumulation mode of particles. However, the droplet spacing has an insignificant effect on the capture efficiency when the electrostatic deposition predominates. The increase of droplet charge remarkably improves the capture efficiency, in which the capture of fine particles accounts for the largest proportion. Compared to the droplet charge, the droplet size shows a limited improvement in the capture efficiency. Reducing the droplet velocity prolongs the capture time instead of enhancing the capture capacity per unit time, thereby improving capture efficiency.     

Decoder side information generation techniques in Wyner-Ziv video coding: a review

Multimedia Tools and Applications - In Wyner-Ziv (WZ) video coding, decoder side information (SI) takes a key role in a WZ video codec among other building blocks. In this paper, we review the...     

低渗低温低压水敏性储气层压裂改造技术研究与应用

低渗低温低压水敏性储气层因压裂液快速破胶困难、黏土膨胀水敏伤害严重和压后压裂液返排动力不足等因素，使得压裂增产面临诸多难题。针对上述难题进行了技术攻关，形成了弱交联、低温活化剂与超量破胶剂的低温储层快速破胶技术、有机盐与无机盐双元体系复合防膨技术以及高比例液氮全程助排的排液技术。该压裂增产改造技术使牛101井头屯河组首次获得工业油气流，扩展了三塘湖盆地勘探空间。     

高质量ZnO薄膜的退火性质研究

在LP－MOCVD中，我们利用Zn(C2H5)2作Zn源，CO2作氧源，在（0002）蓝宝石衬底上成功制备出皮c轴取向高度一致的ZnO薄膜，并对其进行500℃-800℃四个不同温度的退火。利用XRD、吸收谱、光致发光谱和AFM等手段研究了退火对ZnO晶体质量和光学性质的影响。退火后，（0002）ZnO的XRD衍射峰强度显著增强，c轴晶格常数变小，同时（0002）ZnOX射红衍射峰半高宽不断减小表明晶粒逐渐增大，这与AFM观察结果较一致。由透射谱拟合得到的光学带隙退火后变小，PL谱的带边发射则加强，并出现红移，蓝带发光被有效抑制，表明ZnO薄膜的质量得到提高。     

Memory-related changes of nitric oxide synthase activity and nitrite level in rat brain

The changes of nitric oxide synthase (NOS) activity and nitrite level in rat brain regions after spatial learning were investigated. NOS activity was assayed by conversion of [3H]L-arginine to [3H]L-citrulline, and a sensitive fluorometric assay for quantification of nitrite was used. Compared with sham-trained rats, NOS activity and nitrite level in hippocampus and cortex, and also the nitrite level in cerebellum, was elevated significantly one day after rats had learnt a water-rewarded spatial alteration task. These results suggest a spatial memory-related changes of endogenous NO in rat brain, and support the idea that NO participates in learning and memory processes.     

变结构变参数设计方法及其在机械CAD中的应用

提出了一种新颖的机械结构设计思想－变结构变参数设计方法，并结合实例，阐述了变结构变参数设计的概念、原则、实施措施和意义。由此对Ｉ－ｄｅａｓ软件包进行了二次开发，编制了发动机曲轴专用ＣＡＤ软件程序，并用某型号发动机曲轴进行了验证。     

实施取水定额管理的几个关键问题探讨

通过对全国23个省级单位出台的用水定额标准进行分析，指出目前定额管理存在6个主要问题：一是概念模糊，二是制定方法不统一、不规范，三是定额标准体系不完善，四是可操作性较差，五是计量系统不完善，六是缺乏取水定额管理信息化平台。提出应采用“取水定额”这一表述，并提出了取水定额的体系，包括基础计量体系、定额制定体系、信息链体系、定期更新体系4部分。明确了取水定额管理体系建设主要内容应包括：法律法规体系、定额制定体系、水价管理体系、信息通道体系。