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基于自适应几何约束ORB的红外双目测距方法

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红外技术 2024年第7期46卷 831-837页

作者：李淮周王帅军王宏曹祥红白振鹏李森郑州轻工业大学建筑环境工程学院河南郑州450001

针对传统特征匹配算法计算效率低、误匹配率高和双目视觉测量精度不足等问题,提出了一种基于自适应几何约束和随机抽样一致性方法的ORB(Oriented FAST and Rotated BRIEF)红外双目测距方法。首先,通过FAST(Features from Accelerated Se... 详细信息

针对传统特征匹配算法计算效率低、误匹配率高和双目视觉测量精度不足等问题,提出了一种基于自适应几何约束和随机抽样一致性方法的ORB(Oriented FAST and Rotated BRIEF)红外双目测距方法。首先,通过FAST(Features from Accelerated Segment Test)算法与BRIEF(Binary Robust Independent Elementary Features)算法检测并描述关键点,采用快速最近邻搜索的算法完成特征点初始匹配。然后,根据初始匹配点对的斜率与距离选择相应的阈值,构建基于斜率与距离的几何约束,剔除明显错误匹配点对。最后利用随机抽样一致性方法去除异常点完成精匹配,结合热像仪标定参数计算出目标物体的距离。实验结果表明,改进的ORB算法与传统算法相比,具有较好的特征点质量和较高的测量精度,测距平均绝对误差为1.64%,具有较好的实用价值。

关键词： ORB算法热红外双目测距自适应阈值几何约束

The P-wave velocity structure of the lithosphere of the North China Craton——Results from the Wendeng-Alxa Left Banner deep seismic sounding profile

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Science China Earth Sciences 2014年第12期57卷 2053-2063页

作者： wang shuaijun wang FuYun ZHANG JianShi JIA ShiXu ZHANG ChengKe ZHAO JinRen LIU BaoFeng Geophysical Exploration Center of China Earthquake Administration

For the first time on the Chinese mainland, long-range wide-angle seismic reflection/refraction profiling technology has been applied to seismic wave phases from different depths and with different attributes within the various blocks of the North China Craton to characterize the structure of the crust and upper mantle lithosphere. By comparative analysis of the seismic wave phase characteristics in each block across a 1500-km-long east-west profile, we have identified conventional Pg, Pci, PmP and Pn phases in the crust, made a clear contrast between PL1 and PL2 waves belonging to two groups of lithospheric-scale phases, and produced a model of crust-mantle velocity structures and tectonic characteristics after one- and two-dimensional calcula- tions and processing. The results show that the thickness of the crust and lithosphere gradually deepens from east to west along the profile. However, at the reflection/refraction interface, seismic waves in each group show obvious localized changes in each block. Also, the depth to the crystalline basement changes greatly, from as much as 7.8 km in the North China fault basin to only about 2 km beneath the Jiaodong Peninsula and Taihang-Ltlliang area. The Moho morphology as a whole ranges from shallow in the east to deep in the west, with the deepest point in the Ordos Block at 47 km; in contrast, the North China Plain Block is uplifting. The L1 interface of the lithosphere is observed only to the west of Taihang Mountains, at a relatively slowly changing depth of about 80 km. The L2 interface varies from 75 to 160 km and shows a sharp deepening to the west of Tai- hang Mountains, forming a mutation belt.

关键词： lithosphere velocity structure long observation distance crustal blocks North China Craton(NCC)

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限幅激励发电机设计及输出性能实验测试研究

防爆电机 2024年第4期59卷 13-15页

作者：王帅军高佳佳许昌电气职业学院电气工程系河南许昌461000

发电机在许多电气领域得到应用,设计了一种限幅激励发电机。通过非接触激励旋转磁铁来实现凸轮往复振动,通过凸轮为压电振子提供接触激励作用。开展实验测试分析,研究结果表明:逐渐提高弹簧刚度后形成更大最佳转速与带宽,凸轮限幅激励... 详细信息

发电机在许多电气领域得到应用,设计了一种限幅激励发电机。通过非接触激励旋转磁铁来实现凸轮往复振动,通过凸轮为压电振子提供接触激励作用。开展实验测试分析,研究结果表明:逐渐提高弹簧刚度后形成更大最佳转速与带宽,凸轮限幅激励满足有效性,大幅减小转速域中的电压波动幅度。输出电压与转速存在峰值最优转速,提高激振力可以使各输出电压下形成更大有效带宽,输出电压发生了大幅波动。该研究有助于增强发电机运行可靠性,改善转速适应能力。

关键词：限幅激励发电机旋磁激励凸轮限幅刚度

Response of soil respiration to environmental and photosynthetic factors in different subalpine forest-cover types in a loess alpine hilly region

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Journal of Forestry Research 2022年第2期33卷 653-665页

作者： Yuanhang Li Sha Lin Qi Chen Xinyao Ma shuaijun wang Kangning He School of Soil and Water Conservation Key Laboratory of State Forestry Administration On Soil and Water ConservationBeijing Forestry UniversityBeijing 100083People’s Republic of China Beijing Engineering Research Center of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083People’s Republic of China Engineering Research Center of Forestry Ecological Engineering Ministry of EducationBeijing Forestry UniversityBeijing 100083People’s Republic of China North China Power Engineering Co. Ltd.of China Power Engineering Consulting GroupChangchun 130021People’s Republic of China Power China Huadong Engineering Corporation Limited Hangzhou 311122People’s Republic of China

Soil respiration(Rs)is important for transport-ing or fixing carbon dioxide from the atmosphere,and even diminutive variations can profoundly influence the carbon ***,the R_(s) dynamics in a loess alpine hilly region with representative sensitivity to climate change and fragile ecology remains poorly *** study investigated the correlation and degree of control between R_(s) and its photosynthetic and environmental factors in five subalpine forest cover *** examined the correlations between R_(s) and variables temperature(T_(10)) and soil moisture content at 10 cm depth(W_(10)),net photosynthetic rate(P_(n))and soil properties to establish multiple models,and the variables were measured for diurnal and monthly vari-ations from September 2018 to August *** results showed that soil physical factors are not the main drivers of R_(s) dynamics at the diel scale;however,the trend in the monthly variation in R_(s) was consistent with that of T_(10)and P_(n).Further,R_(s) was significantly affected by pH,providing further evidence that coniferous forest leaves contribute to soil acidification,thus reducing R_(s).Significant exponential and linear correlations were established between R_(s) and T_(10)and W_(10),respectively,and R_(s) was positively correlated with P_(n).Accordingly,we established a two-factor model and a three-factor model,and the correlation coefficients(R_(2))was improved to different degrees compared with models based only on T_(10) and W_(10).Moreover,temperature sensitivity(Q_(10))was the highest in the secondary forest and lowest in the Larix principis-rupprechtii *** findings suggest that the control of R_(s) by the environment(moisture and tempera-ture)and photosynthesis,which are interactive or comple-mentary effects,may influence spatial and temporal homeo-stasis in the region and showed that the models appropriately described the dynamic variation in R_(s) and the carbon cycle in different forest *** add

关键词： Loess alpine hilly region Soil respiration Environmental factor Photosynthesis factor Q_(10) Two-factor model Three-factor model

Lithospheric structure and faulting characteristics of the Helan Mountains and Yinchuan Basin： Results of deep seismic reflection profiling

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Science China Earth Sciences 2017年第3期60卷 589-601页

作者： LIU BaoJin FENG ShaoYing JI JiFa wang shuaijun ZHANG JianShi YUAN HongKe YANG GuoJun Geophysical Exploration Center of China Earthquake Administration Zhengzhou 450002 China

The Helan Mountains and Yinchuan Basin （HM-YB） are located at the northern end of the North-South tectonic belt, and form an intraplate tectonic deformation zone in the western margin of the North China Craton （NCC）. The HM-YB has a complicated history of formation and evolution, and is tectonically active at the present day. It has played a dominant role in the complex geological structure and modem earthquake activities of the region. A 135-km-long deep seismic reflection profile across the HM-YB was acquired in early 2014, which provides detailed information of the lithospheric structure and faulting characteristics from near-surface to various depths in the region. The results show that the Moho gradually deepens from east to west in the depth range of 40-48 km along the profile. Significant differences are present in the crustal structure of different tectonic units, including in the distribution of seismic velocities, depths of intra-cmstal discontinuities and undulation pattern of the Moho. The deep seismic reflection profile further reveals distinct structural characteristics on the opposite sides of the Helan Mountains. To the east, The Yellow River fault, the eastern piedmont fault of the Helan Mountains, as well as multiple buried faults within the Yinchuan Basin are all normal faults and still active since the Quaternary. These faults have controlled the Cenozoic sedimentation of the basin, and display a ＂negative-flower＂ structure in the profile. To the west, the Bayanhaote fault and the western piedmont fault of the Helan Mountains are east-dipping thrust faults, which caused folding, thrusting, and structural deformation in the Mesozoic stratum of the Helan Mountains uplift zone. A deep-penetrating fault is identified in the western side of the Yinchuan Basin. It has a steep inclination cutting through the middle-lower crust and the Moho, and may be connected to the two groups of faults in the upper crest. This set of deep and shallow fault system con

关键词： North China Craton Deep seismic reflection profile Lithospheric structure Helan Mountains Yinchuan Basin

不同病原体致急性呼吸道感染患儿的炎症指标谱分析及建模应用

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贵州医药 2024年第6期48卷 853-857页

作者：李宝辉王玉高果果刘富迪王率军联勤保障部队第九八九医院检验科河南洛阳471031

目的探讨不同病原体致急性呼吸道感染患儿的炎症指标谱的差别并构建病原体预测模型方法选取2021年7月至2022年6月顺序收治的200例急性呼吸道感染患儿为观察组,另取同期体检健康儿童30名为对照组,(1)采集患儿的血、尿、痰、口咽拭子进行... 详细信息

目的探讨不同病原体致急性呼吸道感染患儿的炎症指标谱的差别并构建病原体预测模型方法选取2021年7月至2022年6月顺序收治的200例急性呼吸道感染患儿为观察组,另取同期体检健康儿童30名为对照组,(1)采集患儿的血、尿、痰、口咽拭子进行炎症指标检测及微生物分析;(2)应用秩和检验和模式识别方法进行炎症指标谱及病原体预测分析。结果(1)根据微生物鉴定结果将患者分为革兰阳性球菌感染组(GPC,52例)、革兰阴性杆菌感染组(GNB,56例)、病毒感染组(VIR,42例)、肺炎支原体/衣原体感染组(MPCP,50例)。(2)秩和检验和主成分分析显示不同病原体致呼吸道感染患儿表达不同的炎症指标谱:GPC组C反应蛋白(CRP)、降钙素原(PCT)、白介素(IL)-4、肿瘤坏死因子(TNF)-α水平较高,IL-2水平降低;GNB组的CRP、PCT、IL-6、IL-10、干扰素(IFN)-γ和白细胞计数(WBC)水平较高,IL-2水平降低;VIR组IL-2、TNF-α、IFN-γ表达水平较高;MPCP组PCT、WBC表达水平较高。(3)最小二乘—支持向量机(LS-SVM)模型的病原体预测效能最高:对GPC组、GNB组、VIR组、MPCP组、健康组的诊断灵敏度分别为84.6%、83.9%、83.3%、80.0%、93.3%,特异度高于93.8%(GPC组)。结论基于多炎症指标构建的病原体预测模型,可准确、快速预测急性呼吸道感染患儿的致病微生物类型,有一定的临床应用价值。

关键词：呼吸道感染炎症指标模式识别病因预测

Crustal P-wave velocity structure in the northeastern margin of the Qinghai-Tibetan Plateau and insights into crustal deformation

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Science China Earth Sciences 2018年第9期61卷 1221-1237页

作者： shuaijun wang Baojin LIU Xiaofeng TIAN Baofeng LIU Xianghui SONG Xiaoguo DENG Yinan SUN Cejun MA Yudong YANG Geophysical Exploration Center of China Earthquake Administration Zhengzhou 450002 China

The transitional area between the northeastern margin of the Qinghai-Tibetan Plateau, Ordos Block and Alxa Block, also being the northern segment of the North-South Seismic Belt, is characterized by considerably high seismicity level and high risk of strong earthquakes. In view of the special tectonic environment and deep tectonic setting in this area, this study used two seismic wide-angle reflection/refraction cross profiles for double constraining, so as to more reliably obtain the fine-scale velocity structure characteristics in both the shallow and deep crust of individual blocks and their boundaries in the study area, and further discuss the seismogenic environment in seismic zones with strong historical earthquakes. In this paper, the P-wave data from the two profiles are processed and interpreted, and two-dimensional crustal velocity structure models along the two profiles are constructed by travel time forward modeling. The results show that there are great differences in velocity structure, shape of intra-crustal interfaces and crustal thickness among different blocks sampled by the two seismic profiles. The crustal thickness along the Lanzhou-Huianbu-Yulin seismic sounding profile （L1） increases from -43 km in the western margin of Ordos Block to -56 km in the Qilian Block to the west. In the Ordos Block, the velocity contours vary gently, and the average velocity of the crust is about 6.30 km s^-1; On the other hand, the velocity structures in the crust of the Qilian Block and the arc-like tectonic zone vary dramatically, and the average crustal velocities in these areas are about 0.10 km s^-1 lower than that of the Ordos Block. In addition, discontinuous low-velocity bodies （LVZ1 and LVZ2） are identified in the crust of the Qilian Block and the arc-like tectonic zone, the velocity of which is 0.10-0.20 krn s^-1 lower than that of the surroundings. The average crustal thickness of the Ordos Block is consistently estimated to be around 43 km along both Pr

关键词： Northeastern margin of the Qinghai-Tibetan Plateau The Ordos Block Crustal velocity structure Deep seismicsounding

Application of S-transform threshold filtering in Anhui experiment airgun sounding data de-noising

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Geodesy and Geodynamics 2018年第4期9卷 320-327页

作者： Chenglong Zheng Xiaofeng Tian Zhuoxin Yang shuaijun wang Zhenyu Fan Geophysical Exploration Center China Earthquake Administration

As a relatively new method of processing non-stationary signal with high time-frequency resolution, S transform can be used to analyze the time-frequency characteristics of seismic signals. It has the following characteristics: its time-frequency resolution corresponding to the signal frequency, reversible inverse transform, basic wavelet that does not have to meet the permit conditions. We combined the threshold method, proposed the S-transform threshold filtering on the basis of S transform timefrequency filtering, and processed airgun seismic records from temporary stations in "Yangtze Program"(the Anhui experiment). Compared with the results of the bandpass filtering, the S transform threshold filtering can improve the signal to noise ratio(SNR) of seismic waves and provide effective help for first arrival pickup and accurate travel time. The first arrival wave seismic phase can be traced farther continuously, and the Pm seismic phase in the subsequent zone is also highlighted.

关键词： S transform Time-frequency filtering Airgun data Threshold filtering De-noising

Acidification and bubble template derived porous g-C_(3)N_(4) for efficient photodegradation and hydrogen evolution

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Chinese Chemical Letters 2020年第10期31卷 2668-2672页

作者： Yixuan wang Fengting He Lin Chen Jie Shang Jiajia wang shuaijun wang Huimin Song Jinqiang Zhang Chaocheng Zhao Shaobin wang Hongqi Sun State Key Laboratory of Petroleum Pollution Control China University of Petroleum(East China)Qingdao 266580China School of Engineering Edith Cowan University270 Joondalup DrivePerth WA 6027Australia China General Nuclear Power Hongda Environmental Science and Technology Co. Ltd.Jinan 250000China Dongying Municipal Bureau of Marine Development and Fisheries Dongying Municipal Marine and Fishery Environmental Monitoring CenterDongying 257091China School of Chemical Engineering and Advanced Materials The University of AdelaideAdelaide SA 5005Australia

Graphitic carbon nitride(g-C_(3)N_(4))as a metal-free candidate of photocatalyst has received worldwide attention because of its great potentials in solar light-induced degradation and hydrogen evolution,yet the industrial application is seriously hindered by the small specific surface area and rapid recombination rate of ***,we demonstrate that porous g-C_(3)N_(4)(HCl-CNU-X)can be prepared via the copolymerization of acidified melamine and a green bubble template(urea).Transmission electron microscopy and nitrogen sorption characterization results show that the prepared HCl-CNU-X possesses an in-plane porous structure and large specific surface area,enabling the exposure of more accessible active *** a result,HCl-CNU-X exhibits both enhanced photocatalytic tetracycline hydrochloride degradation and higher hydrogen evolution than bulk g-C_(3)N_(4).The boosted photocatalytic performance was ascribed to the formation of the porous structure,which dramatically promotes the separation of charge-carriers and facilitates the electron *** work demonstrates that the acidification of nitrogen-rich precursors combined with a bubble-template can develop a new paradigm of highly porous photocatalysts for environmental remediation and water splitting.

关键词： g-C_(3)N_(4) Porous structure Tetracycline hydrochloride Hydrogen evolution Acidification and bubble template Visible light