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Effective transmittance of Fabry–Perot cavity under non-parallel beam incidence

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Chinese Physics B 2024年第1期33卷 449-457页

作者：吕寅生谢品华徐晋李友涛张华荣 School of Environmental Science and Optoelectronic Technology University of Science and Technology of ChinaHefei 230026China Key Laboratory of Environment Optics and Technology Anhui Institute of Optics and Fine MechanicsHFIPSChinese Academy of SciencesHefei 230031China University of Chinese Academy of Sciences Beijing 100049China

The Fabry–Perot(FP) resonant cavity is widely used in laser and spectroscopic measurements due to its unique interference transfer function(ITF). In the ideal case of parallel incident light, the ITF of the FP resonant cavity can be expressed by the Airy function. However, in reality, it is difficult to achieve perfect parallelism with collimated beams. In this article, a theoretical model is established for non-parallel light incidence, which assumes that the non-parallel incident light is a cone-shaped beam, and the cone angle is used to quantify the non-parallelism of the beam. The transmittance function of the FP resonant cavity under non-parallel light incidence is derived. The accuracy of the model is experimentally verified. Based on this model, the effects of divergence angle, tilt angle and FP cavity parameters(reflectivity, cavity length)on the ITF are studied. The reasons for the decrease in peak value, broadening and asymmetry of the interference peak under non-parallel light incidence are explained. It is suggested that a fine balance between the interference peak and the collimation effect of the incident light should be considered in the design and application of FP resonant cavities, especially for tilted applications such as angle-scanned spectroscopy. The research results of this article have certain significance for the design and application of FP resonant cavities.

关键词： Fabry–Pérot(FP)resonant cavity interference transfer function Airy function non-parallel beam incidence

Intelligent pavement condition survey: Overview of current researches and practices

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Journal of Road Engineering 2024年第3期 257-281页

作者： Allen A.zhang Jing Shang Baoxian Li Bing Hui Hongren Gong Lin Li You Zhan Changfa Ai Haoran Niu Xu Chu Zilong Nie Zishuo Dong Anzheng He Hang zhang Dingfeng Wang Yi Peng Yifan wei Huixuan Cheng School of Civil Engineering Southwest Jiaotong University School of Transportation and Geomatics Engineering Shenyang Jianzhu University School of Highway Chang'an University College of Transportation Engineering Tongji University College of Transportation Engineering Nanjing Tech University School of Civil Engineering Central South University

Automated pavement condition survey is of critical importance to road network management. There are three primary tasks involved in pavement condition surveys, namely data collection, data processing and condition evaluation. Artificial intelligence(AI) has achieved many breakthroughs in almost every aspect of modern technology over the past decade, and undoubtedly offers a more robust approach to automated pavement condition survey. This article aims to provide a comprehensive review on data collection systems, data processing algorithms and condition evaluation methods proposed between 2010 and 2023 for intelligent pavement condition survey. In particular, the data collection system includes AI-driven hardware devices and automated pavement data collection vehicles. The AI-driven hardware devices including right-of-way(ROW) cameras,ground penetrating radar(GPR) devices, light detection and ranging(LiDAR) devices, and advanced laser imaging systems, etc. These different hardware components can be selectively mounted on a vehicle to simultaneously collect multimedia information about the pavement. In addition, this article pays close attention to the application of artificial intelligence methods in detecting pavement distresses, measuring pavement roughness, identifying pavement rutting, analyzing skid resistance and evaluating structural strength of pavements. Based upon the analysis of a variety of the state-of-the-art artificial intelligence methodologies, remaining challenges and future needs with respect to intelligent pavement condition survey are discussed eventually.

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综合物探方法在伊犁盆地采空区探测中的应用

地质论评 2024年第S1期70卷 131-132页

作者：李英宾张伟李江坤核工业航测遥感中心石家庄050002 中核集团铀资源地球物理勘查技术中心(重点实验室) 石家庄050002 河北省航空探测与遥感技术重点实验室石家庄050002

为了满足经济快速发展的需求,中国每年的矿石开采量达到数十亿吨,矿石的开采将形成大面积的采空区。如果采空区没有及时有效地回填和灌浆,上覆岩层将在重力作用下坍塌,最终成为采空区塌陷区。采空塌陷区将导致地下水枯竭,农田破坏,生态... 详细信息

为了满足经济快速发展的需求,中国每年的矿石开采量达到数十亿吨,矿石的开采将形成大面积的采空区。如果采空区没有及时有效地回填和灌浆,上覆岩层将在重力作用下坍塌,最终成为采空区塌陷区。采空塌陷区将导致地下水枯竭,农田破坏,生态环境恶化,房屋等建筑物受损,威胁人民生命财产安全。因此,有效探测采空区对环境治理具有重要意义(张键桥等,2021)。

关键词： AMT 磁法采空区

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基于参与因子的储能电站一次调频控制策略

电气工程学报 2024年第2期19卷 200-209页

作者：任立腾张学军闫来清范晟山西大学电力与建筑学院太原030031

为使电池储能高效安全地参与电网一次调频过程,考虑储能电站内部组成构造,提出一种储能电站各储能单元动态参与一次调频的控制策略。首先在系统频率跃出调频死区时,基于参与因子确定参与一次调频的主辅出力单元,提高荷电状态(State of c... 详细信息

为使电池储能高效安全地参与电网一次调频过程,考虑储能电站内部组成构造,提出一种储能电站各储能单元动态参与一次调频的控制策略。首先在系统频率跃出调频死区时,基于参与因子确定参与一次调频的主辅出力单元,提高荷电状态(State of charge,SOC)保持效果,同时协调虚拟正/负惯性与虚拟下垂3种控制方法依据Logistic函数特性出力,改善一次调频效果;其次当系统频率进入调频死区时,依据超短期负荷预测对储能单元荷电状态进行预恢复,提高储能电站调频容量利用率;最后在两种系统工况下仿真验证,结果表明所提控制策略的有效性。

关键词：储能电站一次调频参与因子荷电状态预恢复

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Identifying defect energy levels using DLTS under different electron irradiation conditions

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Nuclear Science and Techniques 2017年第12期28卷 262-268页

作者： Chun-sheng Guo Ruo-Min Wang Yu-wei zhang Guo-Xi Pei Shi-wei Feng Zhao-Xian Li College of Electronic Information and Control Engineering Beijing University of TechnologyBeijing 100124China Wuxi EL Pont Group Wuxi 214151China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Electron beams of 0.5, 1.5, 2.0, and 5.0 MeV were used to irradiate n-Si diodes to fluences of5.5×10^(13), 1.7×10^(14), and 3.3×1014 e cm^(-2). The forward voltage drop, minority carrier lifetime, and deep level transient spectroscopy(DLTS) characteristics of silicon p–n junction diodes before and after irradiation were compared. At the fluence of 3.3×10^(14) e cm^(-2), the forward voltage drop increased from 1.25 V at 0.5 MeV to 7.96μs at 5.0 MeV, while the minority carrier lifetime decreased significantly from 7.09 ls at 0.5 MeV to 0.06μs at 5.0 MeV. Six types of changes in the energy levels in DLTS spectra were analyzed and discussed.

关键词： Electron irradiation Deep level transient spectroscopy (DLTS) Minority carrier life time Silicon diode

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水冷型高功率动力电池包冷却结构优化

机械设计与制造 2024年第9期 223-227页

作者：张威罗仁宏方超武汉交通职业学院汽车学院湖北武汉430065 武汉商贸职业学院现代工业技术学院湖北武汉438401 浙吉利汽车研究院有限公司浙江杭州315336

车用高功率动力电池放电倍率大、产热快,易出现电芯过热问题,以优化水冷型高功率电池模组放电散热能力为研究目的,对电池模组冷却参数进行组合探究。搭建模组放电-产热耦合仿真模型,以冷却液温度T、流速V,冷管宽度W、高度H为优化边界建... 详细信息

车用高功率动力电池放电倍率大、产热快,易出现电芯过热问题,以优化水冷型高功率电池模组放电散热能力为研究目的,对电池模组冷却参数进行组合探究。搭建模组放电-产热耦合仿真模型,以冷却液温度T、流速V,冷管宽度W、高度H为优化边界建立四因素-四水平正交试验,利用极差分析法完成了各因素对响应目标影响的权重计算,结果显示:对模组最高温度和最大温差影响最大的因素分别是冷却液温度和流速。在权重计算结果基础上结合响应目标直方图和电芯表面温度分布图确定了全组最优解,较优方案Ι台架试验结果与仿真值相吻合,验证了本次优化方法的正确性。

关键词：水冷型电池包温控能力电-热耦合模型正交试验

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A direct coupling analysis method of hydroelastic responses of VLFS in complicated ocean geographical environment

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Journal of Hydrodynamics 2019年第3期31卷 582-593页

作者： Jun Ding You-sheng Wu Ye Zhou Zhi-wei Li Chao Tian Xue-feng Wang Zheng-wei zhang Xiao-long Liu China Ship Scientific Research Center Wuxi 214082 China School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200240 China

In this paper a direct coupling analysis method (DCAM) of hydroelastic responses of a very large floating structures (VLFS) in complicated geographical environment is presented. In this method the three-dimensional hydroelasticity theory of floating bodies is combined with the shallow water wave theory, to allow for proper description of the influence of uneven seabed and sheltering effect of islands on the hydroelastic responses of a VLFS deployed near island and reefs in shallow sea. This method and the numerical procedures were verified and validated by comparison-between the predictions and the model test results of a 3-module VLFS and an 8-module VLFS in two simulated shallow sea regions with different seabed topography.

关键词： Direct coupling analysis method very large floating structure (VLFS) hydroeiasticity complicated environment

Protein tyrosine phosphatase 1B inhibitory activities of ursane-type triterpenes from Chinese raspberry, fruits of Rubus chingii

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Chinese Journal of Natural Medicines 2019年第1期17卷 15-21页

作者： zhang Xiang-Yu LI wei WANG Jian LI Ning CHENG Mao-sheng KOIKE Kazuo Key Laboratory of Structure-Based Drug Design&Discovery Ministry of EducationShenyang Pharmaceutical University School of Pharmaceutical Engineering Shenyang Pharmaceutical University Faculty of Pharmaceutical Sciences Toho University

Protein tyrosine phosphatase 1 B(PTP1 B) has led to an intense interest in developing its inhibitors as anti-diabetes, anti-obesity and anti-cancer agents. The fruits of Rubus chingii(Chinese raspberry) were used as a kind of dietary traditional Chinese medicine. The methanolic extract of R. chingii fruits exhibited significant PTP1 B inhibitory activity. Further bioactivity-guided fractionation resulted in the isolation of three PTP1 B inhibitory ursane-type triterpenes: ursolic acid(1), 2-oxopomolic acid(2), and 2α, 19α-dihydroxy-3-oxo-urs-12-en-28-oic acid(3). Kinetics analyses revealed that 1 was a non-competitive PTP1 B inhibitor, and 2 and 3 were mixed type PTP1 B inhibitors. Compounds 1-3 and structurally related triterpenes(4-8) were further analyzed the structure-activity relationship, and were evaluated the inhibitory selectivity against four homologous protein tyrosine phosphatases(TCPTP, VHR, SHP-1 and SHP-2). Molecular docking simulations were also carried out, and the result indicated that 1, 3-acetoxyurs-12-ene-28-oic acid(5), and pomolic acid-3β-acetate(6) bound at the allosteric site including α3, α6, and α7 helix of PTP1 B.

关键词： Protein tyrosine phosphatase 1B Raspberry Rubus chingii Triterpene Ursane

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胶西北海岸带海底基岩矿床开采海水入浸防治

现代矿业 2024年第3期40卷 203-207页

作者：盛建华张颖卫茂萱韩代成烟台市自然资源和规划局烟台市社会保险服务中心山东省地质科学研究院

海底基岩矿床顶部分布着大面积的海水,开采过程中存在海水突入矿坑问题。以胶西北海岸带区域为研究背景,对矿坑涌突水的影响因素及涌水量进行分析,并提出防治措施。结果表明,自然灾害、开采活动、孔隙含水层是导致矿坑涌突水主要原因;... 详细信息

海底基岩矿床顶部分布着大面积的海水,开采过程中存在海水突入矿坑问题。以胶西北海岸带区域为研究背景,对矿坑涌突水的影响因素及涌水量进行分析,并提出防治措施。结果表明,自然灾害、开采活动、孔隙含水层是导致矿坑涌突水主要原因;提出了留设保安护顶矿(岩)柱,钻孔注浆,加强地表防海水入浸配套设施建设,提高井下排水系统能力,构筑防水闸门等措施。胶西北海岸带海底金矿开采时-165m标高以上设为保安护顶矿柱是安全的,北皂煤矿-200m以上设为保安护顶矿柱是安全的;海底金矿极限开采高度为-65~-87.2m,北皂煤矿极限高度为-120~-160m,可以作为整个海底矿床开采完毕后回采保安护顶矿柱时的参考依据。

关键词：海底金矿海底煤矿保安护顶矿(岩)柱矿柱回采