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FY-2A与GMS-5红外通道遥感数据的辐射定标

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应用气象学报 2001年第1期12卷 79-84页

作者：谷松岩邱红范天锡国家暴雨实验室北京大学地球物理系北京大学地球物理系北京100871 国家卫星气象中心北京100081

该文通过辐射传输模拟计算和匹配数据统计分析实现了 FY- 2 A和 GMS- 5红外通道间的辐射定标 .以辐射定标为基础将 FY- 2 A红外通道和 GMS- 5红外 A通道的遥感资料融合应用 ,可以得到时间分辨率更高、空间视野更为广阔的静止卫星遥感资料 .

关键词：红外遥感数据辐射定标

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星载双频风场雷达热带气旋降雨区测风模拟

应用气象学报 2012年第4期23卷 467-477页

作者：窦芳丽卢乃锰谷松岩中国气象科学研究院北京100081 中国气象局中国遥感卫星辐射测量和定标重点开放实验室、国家卫星气象中心北京100081

基于大气辐射传输理论分别建立Ku波段和C波段的降雨模型,模拟热带气旋降雨区洋面的雷达回波并反演了洋面10 m风场,用于研究降雨对测风的影响以及风云三号双频风场雷达(WFR)的测风能力。分析表明:回波的衰减或增强取决于降雨衰减项和后... 详细信息

基于大气辐射传输理论分别建立Ku波段和C波段的降雨模型,模拟热带气旋降雨区洋面的雷达回波并反演了洋面10 m风场,用于研究降雨对测风的影响以及风云三号双频风场雷达(WFR)的测风能力。分析表明:回波的衰减或增强取决于降雨衰减项和后向散射项的相对大小;热带气旋的降雨使反演风速偏小,风向精度降低,Ku波段相对于C波段更易受影响,在高风速(超过30 m·s^(-1))条件下,可达5～20 m·s^(-1)的负风速偏差。反演结果表明:双频反演的新方法能够结合Ku波段与C波段的优势,双频最大似然估计(MLE)方法在分辨率上优于C波段单频反演,相对Ku单频反演能降低降雨对测风的衰减作用,结合双频MLE方法和C波段单频反演优势的分区反演方法可以显著减小降雨偏差,提高风速反演精度,在有风云三号湿度计同步观测的条件下,是提高热带气旋降雨区测风精度的有效手段。

关键词：降雨模型风场微波散射计辐射传输

青藏高原地区TRMM PR地面降雨率的修正

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应用气象学报 2015年第5期26卷 636-640页

作者：李嘉睿卢乃锰谷松岩中国气象科学研究院北京100081 国家卫星气象中心北京100081

为掌握并改进青藏高原地区TRMM卫星降水雷达(precipitation radar,PR)地面降雨率准确度,统计分析了2005—2007年TRMM PR 2A25资料和逐小时地面雨量计,结果表明:青藏高原地区TRMM PR地面降雨率在层云降水时平均偏低35%,在对流云降水时平... 详细信息

为掌握并改进青藏高原地区TRMM卫星降水雷达(precipitation radar,PR)地面降雨率准确度,统计分析了2005—2007年TRMM PR 2A25资料和逐小时地面雨量计,结果表明:青藏高原地区TRMM PR地面降雨率在层云降水时平均偏低35%,在对流云降水时平均偏高42%。Z-R关系的适用性是PR产生偏差的原因之一,研究将TRMM PR层云降水模型中20℃层Z-R关系的初始系数A和b分别修正为0.0288和0.6752,对流云降水模型中20℃层的初始系数A和b分别修正为0.0406和0.5809,得到两类降水模型0℃层与20℃层之间不同高度Z-R关系的更新系数。检验结果表明,修正降水模型后能够提高青藏高原地面降雨率测量的准确度。

关键词：青藏高原星载雷达雨量计地面降雨率 Z-R关系

Volume of fluid simulation of single argon bubble dynamics in liquid steel under RH vacuum conditions

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Journal of Iron and Steel Research International 2024年第4期31卷 828-837页

作者： gu-jun Chen Sheng-ping He College of Materials Science and Engineering Yangtze Normal UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

Single argon bubble dynamics in liquid steel under Ruhrstahl-Heraeus(RH)vacuum conditions were simulated using the volume of fluid method,and the ideal gas law was used to consider bubble growth due to heat transfer and pressure *** simulation with a constant bubble density was also performed to validate the numerical method,and the predicted terminal bubble shape and velocity were found to agree with those presented in the Grace diagram and calculated by drag correlation,*** simulation results under RH conditions indicate that the terminal bubble shape and velocity cannot be *** primary bubble growth occurs within a rising distance of 0.3 m owing to heating by the high-temperature liquid steel;subsequently,the bubble continues to grow under equilibrium with the hydrostatic *** the initial diameter is 8-32 mm,the bubble diameter and rising velocity near the liquid surface are 80-200 mm and 0.5-0.8 m/s,*** bubble rises rectilinearly with an axisymmetric shape,and the shape evolution history includes an initial sphere,(dimpled)ellipsoid,and spherical cap with satellite bubbles.

关键词： Bubble dynamics Liquid steel Volume of fluid Bubble growth Bubble shape Rising velocity

An internal ballistic model of electromagnetic railgun based on PFN coupled with multi-physical field and experimental validation

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Defence Technology（防务技术） 2024年第2期32卷 254-261页

作者： Benfeng gu Haiyuan Li Baoming Li National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyNanjing 210094China

To accelerate the practicality of electromagnetic railguns,it is necessary to use a combination of threedimensional numerical simulation and experiments to study the mechanism of bore *** this paper,a three-dimensional numerical model of the augmented railgun with four parallel unconventional rails is introduced to simulate the internal ballistic process and realize the multi-physics field coupling calculation of the rail gun,and a test experiment of a medium-caliber electromagnetic launcher powered by pulse formation network(PFN)is carried *** test methods such as spectrometer,fiber grating and high-speed camera are used to test several parameters such as muzzle initial velocity,transient magnetic field strength and stress-strain of *** the simulation results and experimental data,the damage condition of the contact surface is analyzed.

关键词： Internal ballistic modeling Electromagnetic rail gun Multi-physics field coupling Experimental validation PFN

Ultra-simplified diffraction-based computational spectrometer

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Light(Science & Applications) 2024年第6期13卷 1022-1031页

作者： Chuangchuang Chen Honggang gu Shiyuan Liu State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhanHubei430074China Optics Valley Laboratory WuhanHubei430074China

Miniaturizing spectrometers for compact and cost-effective mobile platforms is a major challenge in current spectroscopy research,where conventional spectrometers are impractical due to their bulky *** miniaturized designs primarily rely on precalibrated response functions of nanophotonic structures to encode spectral information captured in a snapshot by detector *** spectrum reconstruction is achieved through computational techniques,but this requires precise component design,high-precision fabrication,and *** propose an ultra-simplified computational spectrometer that employs a one-to-broadband diffraction decomposition strategy facilitated by a numerical regularized transform that depends only on the spectrum of the diffracted *** key feature of our design is the use of a simple,arbitrarily shaped pinhole as the partial disperser,eliminating the need for complex encoding designs and full spectrum *** spectrometer achieves a reconstructed spectral peak location accuracy of better than 1 nm over a 200 nm bandwidth and excellent resolution for peaks separated by 3 nm in a bimodal spectrum,all within a compact footprint of under half an ***,our approach also reveals a breakthrough in broadband coherent diffractive imaging without requiring any prior knowledge of the broadband illumination spectrum,assumptions of non-dispersive specimens,or correction for detector quantum efficiency.

关键词： simplified spectrum illumination

风云三号(02)批卫星微波氧气吸收通道降水特性

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应用气象学报 2012年第2期23卷 223-230页

作者：张淼卢乃锰谷松岩张文建中国气象科学研究院北京100081 中国气象局中国遥感卫星辐射测量和定标重点开放实验室国家卫星气象中心北京100081 世界气象组织综合观测与信息系统司瑞士日内瓦C．P．2300

我国新一代极轨业务气象卫星风云三号(02)批计划2012年发射。该文利用UWNMS模拟2005年Katrina飓风的结果作为基础数据集,借助VDISORT微波辐射传输模式对风云三号(02)批计划装载的微波探测仪器中50～60 GHz和新增的118.75 GHz频点的降水... 详细信息

我国新一代极轨业务气象卫星风云三号(02)批计划2012年发射。该文利用UWNMS模拟2005年Katrina飓风的结果作为基础数据集,借助VDISORT微波辐射传输模式对风云三号(02)批计划装载的微波探测仪器中50～60 GHz和新增的118.75 GHz频点的降水特性进行初步研究。首先通过晴空权重函数匹配,选择出50～60 GHz与118.75 GHz频点匹配关系较好的4对通道。敏感性分析表明:各通道对各种水凝物粒子均很敏感,可用于改进现有业务降水反演算法。分别选取50～60 GHz 4个通道、118.75 GHz 4个通道、50～60 GHz及118.75 GHz全部通道3种不同的通道组合进行反演试验。结果表明:将50～60 GHz及118.75 GHz通道联合起来进行降水反演可提高降水反演的精度,并可以更好地区分降水区与非降水区。

关键词：微波温度计微波湿度计降水反演

Prediction of liquid circulation flow rate in RH degasser:improvement of decarburization at low atmospheric pressure

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Journal of Iron and Steel Research International 2024年第7期31卷 1661-1667页

The two-fluid model coupled with population balance model was used for simulating the gas-liquid flow in the Ruhrstahl-Heraeus(RH)*** predicted circulation flow rate was compared with that measured from a water model experiment to validate the mathematical ***,influence of snorkel immersion depth on liquid circulation flow rate was numerically investigated under an atmospheric pressure of 101 and 84 kPa,*** result indicates that the circulation flow rate of the RH degasser in the high-altitude area was severely reduced because of the decrease in atmospheric ***,increasing the snorkel immersion depth from 0.5 to 0.7 m can compensate for the decrease in atmospheric *** test result indicates that decarburization rate is significantly enhanced by increasing the snorkel immersion *** optimization,the percentage of heats with a final carbon content less than 0.002 wt.%is significantly increased from 22.0%to 96.4%.

关键词： RH degasser Two-fluid model Population balance model-Circulation flow rate Decarburization Snorkel immersion depth

A Comparison of Four Neural Networks Algorithms on Locomotion Intention Recognition of Lower Limb Exoskeleton Based on Multi-source Information

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Journal of Bionic Engineering 2024年第1期21卷 224-235页

作者： Duojin Wang Xiaoping gu Hongliu Yu Institute of Rehabilitation Engineering and Technology University of Shanghai for Science and Technology516 Jungong RoadShanghai 200093China Shanghai Engineering Research Center of Assistive Devices 516 Jungong RoadShanghai 200093China

Lower Limb Exoskeletons(LLEs)are receiving increasing attention for supporting activities of daily *** such active systems,an intelligent controller may be *** this paper,we proposed a locomotion intention recognition system based on time series data sets derived from human motion *** of input data and Deep Learning(DL)algorithms,this framework enables the detection and prediction of users’movement *** makes it possible to predict the detection of locomotion modes,allowing the LLEs to provide smooth and seamless *** pre-processed eight subjects were used as input to classify four scenes:Standing/Walking on Level Ground(S/WOLG),Up the Stairs(US),Down the Stairs(DS),and Walking on Grass(WOG).The result showed that the ResNet performed optimally compared to four algorithms(CNN,CNN-LSTM,ResNet,and ResNet-Att)with an approximate evaluation indicator of 100%.It is expected that the proposed locomotion intention system will significantly improve the safety and the effectiveness of LLE due to its high accuracy and predictive performance.

关键词： Lower limb exoskeletons(LLEs) Locomotion intention ResNet Multi-source