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Reconstruction algorithm for cross-waveband optical computing imaging

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Chinese Physics B 2024年第10期33卷 233-239页

作者： Jin-Tao Xie Shu-Hang Bie Ming-Fei Li Yuan-Jin Yu Yi-Fei Li Jin-Guang Wang Bao-Gang Quan Ling-An Wu Institute of Physics Chinese Academy of SciencesBeijing 100190China school of Physical sciences University of Chinese Academy of SciencesBeijing 100049China school of Automation Beijing Institute of TechnologyBeijing 100081China

In a single-pixel fast imaging setup,the data collected by the single-pixel detector needs to be processed by a computer,but the speed of the latter will affect the image reconstruction *** we propose two kinds of setups which are able to transform non-visible into visible light imaging,wherein their computing process is replaced by a camera integration *** image captured by the camera has a low contrast,so here we present an algorithm that can realize a high quality image in near-infrared to visible cross-waveband *** scheme is verified both by simulation and in actual *** setups demonstrate the great potential for single-pixel imaging and high-speed cross-waveband imaging for future practical applications.

关键词： optical computing imaging single-pixel imaging

Provenance of Conglomerate and Sandstone from Early Permian Shoushangou Formation in Xi Ujimqin,Inner Mongolia:Implications for Understanding Paleo-Asian Ocean Subduction

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 10-31页

作者： ZHANG Yingli GUO Xianqing MA Shouxian MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesCAGSBeijing 100037China Chinese Academy of geological sciences Beijing 100037China

During the Late Carboniferous to Early Permian,a rift was formed by post-collisional extension after ocean closure or an island arc-related basin formed by Paleo-Asian Ocean(PAO)subduction in the Xi Ujimqin ***,the closure time of the PAO is still under ***,to identify the origin of the PAO,the geochemistry and U-Pb age of zircons were analyzed for the extra-large deep marine,polymict clastic boulders and sandstones in the Shoushangou Formation within the *** analyses revealed magmatic activity and tectonic *** conglomerates include megaclasts of granite(298.8±9.1 Ma)and granodiorite porphyry(297.1±3.1 Ma),which were deposited by muddy debris *** of this study demonstrated that the boulders of granitoids have the geochemistry of typical I-type granite,characterized by low Zr+Nb+Ce+Y and low Ga/Al *** granitoid boulders were formed in island arc setting,indicating the presence of arc magmatism in the area that is composed of the Late Carboniferous to Early Permian subduction-related granitoid in southern Xi *** diagrams for determining sedimentary provenance using major and trace elements indicate that Shoushangou sediments originated from continental island arc-related felsic *** zircon U-Pb age cluster of 330–280 Ma was obtained,indicating input from granite,ophiolite,Xilin Gol complex,and Carboniferous sources to the *** basin was geographically developed behind the arc during the Early Permian period because the outcropped intrusive rocks in the Late Carboniferous to Early Permian form a volcanic *** comprehensive analyses of source areas suggest that Shoushangou sediments developed in a backarc basin in response to the northward subduction of the *** backarc basin and intrusive rocks,in addition to previously published Late Carboniferous to Early Permian magmatic rocks of arc unit in Xilin Gol,confirm the presence of an Early Permian trencharc-basin system in the region,r

关键词： provenance analysis backarc basin Shoushangou Formation Early Permian Central Asian Orogenic Belt

Dynamic-based model for calculating the boulder impact force in debris flow

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Journal of Mountain Science 2024年第6期21卷 1930-1940页

作者： YANG Chaoping ZHANG Shaojie YIN Yueping YANG Hongjuan WEI Fangqiang State Key Laboratory of Mountain Hazards and Engineering Resilience Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610299China University of Chinese Academy of sciences Beijing 100049China China Institute of geological Environment Monitoring Beijing 100081China Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China Chongqing school University of Chinese Academy of SciencesChongqing 400714China

The boulder impact force in debris flow is generally calculated by static methods such as the cantilever beam ***,these methods cannot describe the dynamic scenario of boulder collision on structures,so the inertia and damping effects of the structures are not involved causing an overestimation on the boulder impact *** order to address this issue,a dynamic-based model for calculating the boulder impact force of a debris flow was proposed in this study,and the dynamic characteristics of a cantilever beam with multiple degrees of freedom under boulder collision were *** using the drop-weight method to simulate boulders within debris flow,seven experiments of drop-weight impacting the cantilever beam were used to calibrate the error of the dynamicbased *** indicate that the dynamic-based model is able to reconstruct the impact force history on the cantilever beam during impact time and the error of dynamic-based model is 15.3%in calculating boulder impact force,significantly outperforming the cantilever beam model’s error of 285%.Therefore,the dynamic-based model can overcome the drawbacks of the static-based models and provide a more reliable theoretical foundation for the engineering design of debris flow control structures.

关键词： Debris flow Impact force Boulder collision Dynamic-based model Engineering design

Geochemistry and Zircon U-Pb and Hf Isotopes of Early Devonian Hardawu Granites in the Eastern Segment of the Ultrahigh-Pressure Metamorphic Belt, Northern Qaidam Basin

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Journal of Earth Science 2024年第3期35卷 866-877页

作者： Hua Li Ming Wang Jiqing Li Haikui Tong Jiaxiang Dong Minggang Tian Xiaolin Chen Leguang Li Ting Xie Xiong Li Yuying Che Qinghai geological Survey Xining 810000China Technology Innovation Center for Exploration and Exploitation of Strategic Mineral Resources in Plateau Desert Region Ministry of Natural ResourcesXining 810000China Qinghai geological Survey Institute Xining 810000China geological Exploration Institute of Shandong Zhengyuan Jinan 271000China school of Earth Science China University of GeosciencesWuhan 430074China

The Hardawu granites in the eastern segment of the ultrahigh-pressure metamorphic belt,the northern Qaidam Basin,were studied by whole-rock major and trace elements and in-situ zircon U-Pb geochronology and Hf isotopes to discuss the petrogenesis and tectonic *** results show that the granites have a crystallization age of 401±3 Ma,suggesting that they were formed in the Early *** granites have SiO2 contents of 75.32 wt.%-76.05 wt.%,total alkali contents of 8.23 wt.%-8.36 wt.%,and K2O/Na2O ratios of *** were rich in K2O,poor in TiO2,MnO,MgO,and P2O5,and have A/CNK values of 1.05-1.07,Rittmann indexδvalues of 2.05-2.14,and differentiation index(DI)values of *** are high potassium calc-alkaline,weakperaluminum,and highly differentiated I-type *** granites also show enrichment of large ion lithophile elements(LILE)such as Rb,Ba,and Th,and depletion of high field strength elements(HFSE)such as Nb,Ta,and *** total REE concentrations range from 169 ppm to 232 ppm,with enrichments of light rare earth elements and negative Eu anomalies(δEu=0.39-0.55).The zirconεHf(t)values range from-0.65 to-2.29,and the two-stage model ages(tDM2)changed within a small range of 1.44 to 1.54 Ga,indicating that the magma of the Hardawu granites was originated from the partial melting of Mesoproterozoic lower crustal *** with previous studies,we suggest that the Hardawu granites were formed in the extensional tectonic setting after the collision between the Qaidam Block and the central and southern Qilian Block in the Early Devonian.

关键词： granite Early Devonian petrogenesis tectonic implication Qaidam Basin geochemistry

Comparison of debris flow susceptibility assessment methods:support vector machine,particle swarm optimization,and feature selection techniques

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Journal of Mountain Science 2024年第2期21卷 397-412页

作者： ZHAO Haijun WEI Aihua MA Fengshan DAI Fenggang JIANG Yongbing LI Hui Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China Hebei Province Key Laboratory of Sustained Utilization&Development of Water Recourse Hebei GEO UniversityShijiazhuang 050031China school of Water Resources and Environment Hebei GEO UniversityShijiazhuang 050031China The Sixth geological Brigade of geological Mineral Exploration and Development Bureau of Hebei Province Shijiazhuang 050085China

The selection of important factors in machine learning-based susceptibility assessments is crucial to obtain reliable susceptibility *** this study,metaheuristic optimization and feature selection techniques were applied to identify the most important input parameters for mapping debris flow susceptibility in the southern mountain area of Chengde City in Hebei Province,China,by using machine learning *** total,133 historical debris flow records and 16 related factors were *** support vector machine(SVM)was first used as the base classifier,and then a hybrid model was introduced by a two-step ***,the particle swarm optimization(PSO)algorithm was employed to select the SVM model ***,two feature selection algorithms,namely principal component analysis(PCA)and PSO,were integrated into the PSO-based SVM model,which generated the PCA-PSO-SVM and FS-PSO-SVM models,*** statistical metrics(accuracy,recall,and specificity)and the area under the receiver operating characteristic curve(AUC)were employed to evaluate and validate the performance of the *** results indicated that the feature selection-based models exhibited the best performance,followed by the PSO-based SVM and SVM ***,the performance of the FS-PSO-SVM model was better than that of the PCA-PSO-SVM model,showing the highest AUC,accuracy,recall,and specificity values in both the training and testing *** was found that the selection of optimal features is crucial to improving the reliability of debris flow susceptibility assessment ***,the PSO algorithm was found to be not only an effective tool for hyperparameter optimization,but also a useful feature selection algorithm to improve prediction accuracies of debris flow susceptibility by using machine learning *** high and very high debris flow susceptibility zone appropriately covers 38.01%of the study area,where debris flow may occur under intens

关键词： Chengde Feature selection Support vector machine Particle swarm optimization Principal component analysis Debris flow susceptibility

Crack mechanism of ground fissures in loess layer of Fenwei Basin, China

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Journal of Mountain Science 2024年第5期21卷 1683-1696页

作者： LI Cong LU Quanzhong WANG Feiyong LUO Wenchao XU Qiang school of geological Engineering and Geomatics Chang’an UniversityXi’an 710054China Key Laboratory of Western Mineral Resources and geological Engineering Ministry of EducationXi’an 710054China Observation and Research Station of Ground Fissure and Land Subsidence Ministry of Natural ResourcesXi’an 710054China school of Engineering and Technology China University of GeosciencesBeijing 100083China

The Fenwei Basin, covered by loess, experiences severe ground fissure disasters. These disasters disrupt the continuity of the loess and pose significant threats to engineering construction safety along transportation routes. Nevertheless, the crack characteristics and the influence zone of ground fissures in the loess layer remain inadequately investigated. To effectively prevent and control ground fissure disasters, physical model tests and the PFC(particle flow code) numerical simulation method are used to investigate the crack mechanism of buried ground fissures in the loess layer. The results show that there are two main cracks in the layer profile, which have a Y-shape morphology. As the dip angle of the preset cracks increased from 60° to 90°, the main deformation zone at the surface gradually shifted towards the footwall. The process of crack propagation from depth to surface is divided into five stages. Additionally, the results confirm the accuracy of the width of the rupture zone d2in the footwall calculated by the cantilever beam theory. These findings can offer theoretical guidance for determining the avoidance distance of ground fissures in loess regions, as well as for implementing disaster prevention and corresponding control measures for various stages of buried ground fissure propagation.

关键词： Ground fissure Fenwei Basin Physical model test Particle flow code Crack propagation

Effect of external magnetic field on the instability of THz plasma waves in nanoscale graphene field-effect transistors

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Chinese Physics B 2024年第4期33卷 683-689页

作者：张丽萍孙宗耀李佳妮苏俊燕 school of sciences Lanzhou University of TechnologyLanzhou 730050China

The instability of plasma waves in the channel of field-effect transistors will cause the electromagnetic waves with THz *** on a self-consistent quantum hydrodynamic model,the instability of THz plasmas waves in the channel of graphene field-effect transistors has been investigated with external magnetic field and quantum *** analyzed the influence of weak magnetic fields,quantum effects,device size,and temperature on the instability of plasma waves under asymmetric boundary conditions *** results show that the magnetic fields,quantum effects,and the thickness of the dielectric layer between the gate and the channel can increase the radiation ***,we observed that increase in temperature leads to a decrease in both oscillation frequency and instability *** numerical results and accompanying images obtained from our simulations provide support for the above conclusions.

关键词： graphene field-effect transistors external magnetic field radiation frequency instability increment

The Strategic Analysis of Demand Forecast-Sharing in a Hybrid-Format Online Platform Supply Chain

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Journal of Systems Science and Systems Engineering 2024年第3期33卷 281-310页

作者： Jing Zhao Zijun Yin Guobiao Zhou school of Mathematical sciences Tiangong UniversityTianjin300387China

This paper examines the optimal forecast-sharing strategy in a hybrid-format online platform supply chain where a supplier sells a product through agency format and reselling format provided by a platform retailer who possesses demand forecasts from two *** asymmetry and co-opetitive relationship arise between the platform retailer and the supplier,which affect their operational decisions and the supply chain’s *** improve supply chain efficiency,we compare different forecast-sharing strategies(i.e.,no forecast sharing,sharing a single forecast,and sharing two forecasts),and analyze the effects of co-opetitive parameters on the optimal forecast-sharing *** analysis shows that forecast sharing is always beneficial to the supplier,and sharing two forecasts is more beneficial than sharing a single *** for the platform retailer and the whole supply chain,forecast sharing is beneficial only under certain conditions,depending on the co-opetitive *** optimal forecast-sharing strategy is the result of a combination of the negative effect of double marginalization in reselling channel and the positive effect of responding pricing to demand uncertainty in agency *** illustrate the parameter regions of the platform retailer’s voluntary sharing,contract sharing,and no sharing,and also find that higher channel competition intensity,higher market share of agency channel,and higher commission rate can promote the platform retailer’s voluntary *** study extends the research scope of demand forecast-sharing and sheds light on the decision-making processes for managing a hybrid-format online platform supply chain.

关键词： Supply chain management hybrid-format online platform demand forecast-sharing co-opetitive relationship channel competition intensity

Sedimentary and Heavy Mineral Records for the Oligocene-Miocene Exhumation of the Easternmost Tianshan

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Journal of Earth Science 2024年第2期35卷 449-461页

作者： Yan Ding Tianyi Shen Guocan Wang Junliang Ji school of Earth sciences Center for Global TectonicsChina University of GeosciencesWuhan430074China State Key Laboratory of geological Processes and Mineral Resources China University of GeosciencesWuhan430078China Hubei Key Laboratory of Critical Zone Evolution School of Geography and Information EngineeringChina University of GeosciencesWuhan430074China

The topography of the Harlik Mountain has a strong impact on the formation of current arid climate in the Turpan-Hami ***,it is still controversial if Harlik Mountain experienced significant exhumation during the Middle to Late Cenozoic according to the previous thermochronology *** features of the Oligocene to Miocene sediments in the foreland basin could provide productive information for resolving the *** peak ages of detrital apatite fission track analysis of the Oligocene–Miocene sandstone in the Turpan-Hami Basin are well comparable with the cooling age records of the Harlik Mountain rocks,indicating that the Oligocene–Miocene Taoshuyuanzi Formation in the basin was mostly derived from the Harlik *** stratigraphic sequence exhibits coarsening upward,reflecting that the source area was in a tectonically active period during the deposition *** mineral assemblages also suggest that the unstable minerals in the sediment increased significantly at the end of the ***,the proportion of apatite increased up-section,while the garnet content decreased significantly,indicating that the Carboniferous metamorphic rocks have been gradually eroded out and more intrusive rocks have been exposed to the *** observations suggest that the Harlik Mountain experienced exhumation during the Oligocene to Miocene,and the denudation depth afterward was probably less than 2.5 km according to the previously apatite(U-Th)/He *** Oligocene–Miocene exhumation probably acted as one of the triggers for the heavy drought of the Turpan-Hami Basin during the Middle–Late Neogene.

关键词： Turpan-Hami Basin Harlik Mountain Taoshuyuanzi Formation Oligocene–Miocene uplift sedimentology structural geology