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Comparison between the Roles of Low-Level Jets in Two Heavy Rainfall Events over South China

Journal of Meteorological Research 2022年第2期36卷 326-341页

作者： Xinyu ZHOU Zhengquan CHENG haowen li Dongming HU Guangzhou Meteorological Observatory Guangzhou 511430 Guangdong Meteorological Observatory Guangzhou 510080

Two heavy rainfall events occurred over the Pearl River Delta during 20-22 May 2020:the first was a warm-sector event and the second a frontal *** on ERA5 reanalysis data and observations from wind profilers and Doppler weather radars,the structures and roles of low-level jets(LLJs)during these two heavy rainfall events were *** results show that:(1)South China was affected by a low-level vortex and a low-level shear line during the two *** two heavy rainfall events were both associated with a synoptic-system-related low-level jet(SLLJ)and a boundary layer jet(BLJ).The coupling of the convergence at the exit of the BLJ and the divergence at the entrance of the SLLJ produced strong lifting for the warm-sector heavy rainfall,and the strong convergence between the LLJs and northerly winds as the cold front moved southwards was the main lifting reason for the frontal heavy rainfall.(2)The BLJ was the main transport of water vapor during the two *** coupling of the BLJ and SLLJ caused the water vapor convergence to be concentrated in the boundary layer during the first process,whereas the strong convergence between the LLJs and northerly winds led to the lower and middle troposphere having strong water vapor convergence during the second process.(3)During the period of these two heavy rainfall events,the lower and middle troposphere remained *** analysis show that the differences in the intensity,location,and direction between the BLJ and SLLJ resulted in the pseudo-equivalent potential temperature advection in the boundary layer being significantly larger than in the lower and middle troposphere,which compensated for the energy loss caused by heavy rainfall and maintained the convective *** findings add to our knowledge on the roles of LLJs in the pre-summer rainfall over South China.

关键词： pre-summer heavy rainfall South China low-level jets water vapor convective instability

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Efficient defect-controlled photocatalytic hydrogen generation based on near-infrared Cu-In-Zn-S quantum dots

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Nano Research 2018年第3期11卷 1379-1388页

作者： Xiao-Yuan liu Guozhen Zhang Hao Chen haowen li Jun Jiang Yi-Tao Long Zhijun Ning School of Physical Science and Technology ShanghaiTech University Shanghai 201210 China Key Laboratory for Advanced Materials & School of Chemistry and Molecular Engineering East China University of Science and Technology Shanghai 200237 China School of Chemistry and Materials Science Hefei National Laboratory for Physical Sciences at the Microscale and CAS Key Laboratory of Mechanical Behavior and Design of Materials (LMBD) University of Science and Technology of China (USTC) Hefei 230026 China

The development of photocatalysts that can effectively harvest visible light is essential for advances in high-efficiency solar-driven hydrogen generation. Herein, we synthesized water soluble CuInS2 （CIS） and Cu-In-Zn-S （CIZS） quantum dots （QDs） by using one-pot aqueous method. The CIZS QDs are well passivated by glutathione ligands and are highly stable in aqueous conditions. We subsequently applied these QDs as a light harvesting material for photocatalytic hydrogen generation. Unlike most small band gap materials that show extremely low efficienc36 these new QDs display remarkable energy conversion efficiency in the visible and near-infrared regions. The external quantum efficiency at 650 nm is - 1.5%, which, to the best of our knowledge, is the highest value achieved until now in the near-infrared region.

关键词： quantum dots photocatalysis hydrogen generation surface defect

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Pertussis toxin–induced inflammatory response exacerbates intracerebral haemorrhage and ischaemic stroke in mice

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Stroke & Vascular Neurology 2022年第1期7卷 29-37页

作者： Ming Zou Yan Feng Yuwhen Xiu Yan li Ying Zhang Junwan Fan haowen li Jingli Cao Wenyan He Wei-Na Jin Tianjin Neurological Institute Tianjin Medical University General HospitalTianjinChina China National Clinical Research Center for Neurological Diseases/Advanced Innovation Center for Human Brain Protection Beijing Tiantan HospitalBeijingChina

Background Stroke is a devastating disease,including intracerebral haemorrhage(ICH)and ischaemic *** evidences indicate that systemic inflammatory cascades after stroke contribute to brain ***,the direct effects and features of systemic inflammation on brain injury,especially comparing between ischaemic and haemorrhagic stroke,are still *** Pertussis toxin(PT)was used to build a pro-inflammatory milieu after ICH and ischaemic stroke in mouse *** neurodeficits,stroke lesion,immune response and blood–brain barrier(BBB)destruction were *** In ICH mouse model,PT-induced systemic inflammation exacerbated neurological deficits,and enlarged haemorrhage lesion and perihaematomal *** also found promoted leucocyte infiltration and inflammatory cytokine release into the brain after PT ***,the integrity of the BBB was further disrupted after receiving ***,we demonstrated that PT enhanced brain inflammation and aggravated stroke severity in middle cerebral artery occlusion mouse *** Our results suggest that PT increases inflammatory response that exacerbates brain injury after ICH or ischaemic stroke in mouse model.

关键词： inflammatory inflammation intracerebral

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Electronic properties of 2H-stacking bilayer MoS_(2)measured by terahertz time-domain spectroscopy

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Frontiers of physics 2023年第5期18卷 161-171页

作者： Xingjia Cheng Wen Xu Hua Wen Jing Zhang Heng Zhang haowen li Francois M.Peeters Qingqing Chen Key Laboratory of Materials Physics Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Micro Optical Instruments Inc. Shenzhen 518118China School of Physics and Astronomy and Yunnan Key Laboratory of Quantum Information of Yunnan Province Yunnan UniversityKunming 650091China Department of Physics University of AntwerpGroenenborgerlaan 171B-2020 AntwerpenBelgium

Bilayer (BL) molybdenum disulfide (MoS_(2)) is one of the most important electronic structures not only in valleytronics but also in realizing twistronic systems on the basis of the topological mosaics in moiré superlattices. In this work, BL MoS_(2) on sapphire substrate with 2H-stacking structure is fabricated. We apply the terahertz (THz) time-domain spectroscopy (TDS) for examining the basic optoelectronic properties of this kind of BL MoS_(2). The optical conductivity of BL MoS_(2) is obtained in temperature regime from 80 K to 280 K. Through fitting the experimental data with the theoretical formula, the key sample parameters of BL MoS_(2) can be determined, such as the electron density, the electronic relaxation time and the electronic localization factor. The temperature dependence of these parameters is examined and analyzed. We find that, similar to monolayer (ML) MoS_(2), BL MoS_(2) with 2H-stacking can respond strongly to THz radiation field and show semiconductor-like optoelectronic features. The theoretical calculations using density functional theory (DFT) can help us to further understand why the THz optoelectronic properties of BL MoS_(2) differ from those observed for ML MoS_(2). The results obtained from this study indicate that the THz TDS can be applied suitably to study the optoelectronic properties of BL MoS_(2) based twistronic systems for novel applications as optical and optoelectronic materials and devices.

关键词： terahertz time-domain spectroscopy bilayer MoS_(2) optoelectronics

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Cellular and molecular imaging for stem cell tracking in neurological diseases

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Stroke & Vascular Neurology 2021年第1期6卷 121-127页

作者： Xiaoxia Yang De-Cai Tian Wenyan He Wei Lv Junwan Fan haowen li Wei-Na Jin Xia Meng China National Clinical Research Center for Neurological Diseases Capital Medical UniversityBeijing Tiantan HospitalBeijingChina Department of Neurology Tianjin Neurological InstituteTianjin Medical University General HospitalTianjinChina

Stem cells(SCs)are cells with strong proliferation ability,multilineage differentiation potential and self-renewal *** transplantation represents an important therapeutic advancement for the treatment strategy of neurological diseases,both in the preclinical experimental and clinical *** and breakthrough SC labelling and tracking technologies are widely used to monitor the distribution and viability of transplanted cells non-invasively and *** we summarised the research progress of the main tracers,labelling methods and imaging technologies involved in current SC tracking technologies for various neurological ***,the applications,challenges and unresolved problems of current SC tracing technologies were discussed.

关键词： neurological diseases clinical

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Fast Steering Mirror Sliding Mode Control Based on Prescribed Performance

Fast Steering Mirror Sliding Mode Control Based on Prescribe...

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第43届中国控制会议

作者： haowen li liang li Zhibin li College of Electrical Engineering and Automation Shandong University of Science and Technology

In order to improve the control performance of the fast steering mirror in laser communication,a prescribed performance control method is studied. First,the fast steering mirror system is analyzed,and the model parameters are obtained according to the open-loop step response. Then,the fixed-time extended state observer is used to estimate the angular velocity and disturbance in real time. Next,error transformation function and performance constraint function are introduced to construct a fast nonsingular terminal sliding mode surface,realizing constrained control of the system output error. Furthermore,the stability of the designed controller is proven through Lyapunov theorem. Finally,the effectiveness and feasibility of the proposed method is verified through experiments.

关键词： fast steering mirror extended state observer prescribed performance sliding mode control

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Automatic Coil Delivery for Uncoiling Machine Based on Image Processing

Automatic Coil Delivery for Uncoiling Machine Based on Image...

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第32届中国控制与决策会议

作者： Gang Zheng Zewen Wang haowen li Siyu liu Xi’an University of Technology Automation and Information Engineering

In order to automate the coil delivery for the cold rolling process and reduce manual operation error,this paper presents a method to locate and track the steel coil using monocular camera and image processing,and the core circle of coil is used as the tracking *** proposed method firstly determines the initial target location information by RHT,then configure the qualification conditions of detection for the next time step based on the target parameters from the last time *** edge detection is used to detect initial contour candidates,limited domain method,contour separation method,quadrant method are adopted to separate contour candidates and filter interference,then fit the target,and track the target by dynamic window *** the theoretical motion trajectory of the target by process a large number of video data,accurately mark the falling point and alignment point of the coil delivery *** has been verified in the industrial field that this method has high accuracy,good tracking stability and real-time performance in the case of sufficient *** with the traditional key-points detection methods based on sensor array,this system requires only a monocular camera,and realize the real-time location tracking,with higher accuracy and controllability,convenient for later maintenance.

关键词： Automatic coil Delivery Image Processing limited Domain Method Contours Separation Method Quadrant Method Target Tracking

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Current research status of immunology in the genomic era

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Science China(life Sciences) 2009年第1期52卷 43-49页

作者： li haowen1,li JinZhi1,ZHAO GuoPing2 & WANG Ying1,2 1 Shanghai Institute of Immunology,Institute of Medical Science,Shanghai Jiaotong University School of Medicine,Shanghai 200025,China 2 Shanghai-MOST Key Laboratory of Health and Disease Genomics,Chinese National Human Genome Center,Shanghai 201203,China 1. Shanghai Institute of Immunology Institute of Medical Science Shanghai Jiaotong University School of Medicine Shanghai 200025 China 2. Shanghai-MOST Key Laboratory of Health and Disease Genomics Chinese National Human Genome Center Shanghai 201203 China

This review updates the current status of immunology research under the influence of genomics,both conceptually and *** particularly highlights the advantages of employing the high-throughput and large-scale technology,the large genomic database,and bioinformatic power in the immunology *** fast development in the fields of basic immunology,clinical immunology(tumor and infectious immunology) and vaccine designing is illustrated with respect to the successful usage of genomic *** also speculate the future research directions of immunology in the era of genomics and post-genomics.

关键词： genomics immunology clinical immunology vaccine design

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Rapid Detection of Accelerants in Fire Debris Using a Field Portable Mid-Infrared Quantum Cascade Laser Based Analyzer

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Open Journal of Applied Sciences 2023年第5期13卷 746-757页

作者： Hao Huang Yongfeng Zhang Fuqiang Dai Xiaobo Yan Altayeb Hamdalnile liyun Wu Tingting Zhang haowen li Frank Inscore Shanghai Fire Research Institute of MEM Shanghai China Micro Optical Instruments Shenzhen China Key Laboratory of Materials Physics Institute of Solid State Physics Chinese Academy of Sciences Hefei China University of Science and Technology of China Hefei China

Arson presents a challenging crime scene for fire investigators worldwide. Key to the investigation of suspected arson cases is the analysis of fire debris for the presence of accelerants or ignitable liquids. This study has investigated the application and method development of vapor phase mid-Infrared (mid-IR) spectroscopy using a field portable quantum cascade laser (QCL) based system for the detection and identification of accelerant residues such as gasoline, diesel, and ethanol in fire debris. A searchable spectral library of various ignitable fluids and fuel components measured in the vapor phase was constructed that allowed for real-time identification of accelerants present in samples using software developed in-house. Measurement of vapors collected from paper material that had been doused with an accelerant followed by controlled burning and then extinguished with water showed that positive identification could be achieved for gasoline, diesel, and ethanol. This vapor phase mid-IR QCL method is rapid, easy to use, and has the sensitivity and discrimination capability that make it well suited for non-destructive crime scene sample analysis. Sampling and measurement can be performed in minutes with this 7.5 kg instrument. This vibrational spectroscopic method required no time-consuming sample pretreatment or complicated solvent extraction procedure. The results of this initial feasibility study demonstrate that this portable fire debris analyzer would greatly benefit arson investigators performing analysis on-site.

关键词： Quantum Cascade Laser (QCL) Mid-Infrared Spectroscopy Fire Debris Analysis Gasoline Vapor Detection Ignitable liquids

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基于多孔卷积神经网络的图像深度估计模型

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计算机应用 2019年第1期39卷 267-274页

作者：廖斌李浩文湖北大学计算机与信息工程学院武汉430062

针对在传统机器学习方法下单幅图像深度估计效果差、深度值获取不准确的问题,提出了一种基于多孔卷积神经网络(ACNN)的深度估计模型。首先,利用卷积神经网络(CNN)逐层提取原始图像的特征图;其次,利用多孔卷积结构,将原始图像中的空间信... 详细信息

针对在传统机器学习方法下单幅图像深度估计效果差、深度值获取不准确的问题,提出了一种基于多孔卷积神经网络(ACNN)的深度估计模型。首先,利用卷积神经网络(CNN)逐层提取原始图像的特征图;其次,利用多孔卷积结构,将原始图像中的空间信息与提取到的底层图像特征相互融合,得到初始深度图;最后,将初始深度图送入条件随机场(CRF),联合图像的像素空间位置、灰度及其梯度信息对所得深度图进行优化处理,得到最终深度图。在客观数据集上完成了模型可用性验证及误差估计,实验结果表明,该算法获得了更低的误差值和更高的准确率,均方根误差(RMSE)比基于机器学习的算法平均降低了30. 86%,而准确率比基于深度学习的算法提高了14. 5%,所提算法在误差数据和视觉效果方面都有较大提升,表明该模型能够在图像深度估计中获得更好的效果。

关键词：多孔卷积卷积神经网络条件随机场深度估计深度学习

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