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Application of Singular Value Decomposition(SVD)to the Extraction of Gravity Anomalies Associated with Ag-Pb-Zn-W Polymetallic Mineralization in the Bozhushan Ore Field,Southwestern China

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Journal of Earth Science 2021年第2期32卷 310-317页

作者： Lingfen Guo Yongqing Chen binbin zhao School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China College of Geographic Science Harbin Normal UniversityHarbin 150025China Sinomine Resource Group Co. Ltd.Beijing 100089China

The Bozhushan Ore Field,located at the western margin of the South China Block,is an important area for Ag-Pb-Zn-W polymetallic mineralization which may be associated with the Late Cretaceous granitic *** this paper,the singular value decomposition(SVD)was effectively applied to decompose gravity data at scale of 1:50000 within the Bozhushan Ore Field to extract deep ore-finding *** gravity anomaly images displaying different scales of the ore-controlling factors were obtained.(1)The low-pass filtered image may reflect the deeply buried geological structures,hidden intrusions and concealed ore *** negative gravity anomaly may reflect the overall distribution of granite bodies in the Bozhushan Ore *** negative gravity anomaly area may correspond to the exposed part of the Baozhushan granitic intrusion and the other corresponds to the concealed part of the granitic *** granitic intrusions are the main ore-controlling factors in this ore district.(2)The band-pass filtered image depicts the shallow concealed geological structures and geological bodies within this study *** are two obvious negative gravity anomalies,which may be created by the hidden granites at different depths at both northwestern and southeastern sides of the exposed granitic *** the two negative gravity anomalies are favorable prospecting areas for various type of polymetallic ore deposits at *** gravity anomalies extracted by using the SVD exactly reflect the distribution of the ore deposits,structures and intrusions,which will give new insights for further mineral exploration in the study area.

关键词： singular value decomposition(SVD) gravity anomaly Ag-Pb-Zn-W polymetallic deposits Bozhushan granitic complex southwestern China

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Identification of the anomaly component using BEMD combined with PCA from element concentrations in the Tengchong tin belt, SW China

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Geoscience Frontiers 2019年第4期10卷 1561-1576页

作者： Yongqing Chen Lina Zhang binbin zhao School of the Earth Sciences and Resources China University of GeosciencesBeijing 100083China CNPC Logging Application Research Institute CNPC LoggingXi’an 710000China Sinomine Resource Group Co. Ltd.Beijing 100089China

Concentration of elements or element groups in a geological body is the result of multiple stages of rockforming and ore-forming geological *** ore-forming element group can be identified by PCA(principal component analysis)and be separated into two components using BEMD(bi-dimensional empirical mode decomposition):(1)a high background component which represents the ore-forming background developed in rocks through various geological processes favorable for mineralization(***,sedimentation and/or metamorphism);(2)the anomaly component which reflects the oreforming anomaly that is overprinted on the high background component developed during *** components are used to identify ore-finding targets more effectively than ore-forming element *** steps of data analytical procedures are described in this paper;firstly,the application of PCA to establish the ore-forming element group;secondly,using BEMD on the o re-forming element group to identify the anomaly components created by different types of mineralization processes;and finally,identifying ore-finding targets based on the anomaly *** method is applied to the Tengchong tin-polymetallic belt to delineate ore-finding targets,where four targets for Sn(W)and three targets for Pb-Zn-Ag-Fe polymetallic mineralization are identified and defined as new areas for further *** is shown that BEMD combined with PCA can be applied not only in extracting the anomaly component for delineating the ore-finding target,but also in extracting the residual component for identifying its high background zone favorable for mineralization from its oreforming element group.

关键词： Bi-dimensional empirical mode decomposition(BEMD) Principal component analysis(PCA) Anomaly components Ore-forming element groups Sn(W)and Pb-Zn-Ag-Fe polymetallic deposits Tengchong tin-polymetallic belt

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Nestedness of waterbird assemblages in the subsidence wetlands recently created by underground coal mining

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Current Zoology 2019年第2期65卷 155-163页

作者： Chunlin LI binbin zhao Yanping WANG School of Resources and Environmental Engineering Anhui University Hefei 230601 China Jiangsu Key Laboratory for Biodiversity and Biotechnology College of Life Sciences Nanjing Normal University Nanjing 210023 China College of Life Sciences Zhejiang University Hangzhou 310058 China

Nestedness has been a research focus in fields of island biogeography and community ecology in recent decades. Although nestedness of faunal assemblages has been investigated in natural wetlands, it remains largely unknown whether and why waterbird communities in artificial wetlands follow n ested patter ns. We exami ned the existence of n ested ness and un derlyi ng drivers in waterbird comm un ities in subside nee wetlands that are recently created by large-scale un derground coal mining in the North China Plain. Twelve point-count surveys for waterbirds were undertaken approximately every 2 weeks in 55 subside nee wetla nds from September 2016 to April 2017. We used the metric WNODF to estimate nestedness of the assemblages. Partial Spearman rank correlations were performed to examine the association between the nestedness and habitat variables (wetland area, landscape connectivity, wetland age, and habitat diversity) as well as life-history traits (body size, clutch size, dispersal ratio, geographical range size, and migrant status) related to species exti notion risk and colon izati on rate. Waterbird assemblages in the subside nee wetla nds were significantly nested. After controlling for other independent variables, the magnitude of nestedness was significantly and negatively correlated with wetland area and species trait linked to extinction risk (i.e., geographical range size). Our results indicate that selective extinction may be the main driver of the nestedness of waterbird assemblages in our study system. However, the nestedness was not due to passive sampling, selective colonization, or habitat diversity. From a conservation viewpoint, both large wetlands and waterbirds with a small geographic range should be protected to maximize the preserved species richness.

关键词： geographical range size nested pattern selective extinction waterbirds WNODF

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A Statistical Estimation Model for the Impact Force of Dry Granular Flow Against Rigid Barrier

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Earthquake Research in China 2020年第1期34卷 110-120页

作者： zhao binbin JIANG Yuanjun Faculty of Engineering China University of GeosciencesWuhan430074China China Electric Power Research Institute Co. Ltd.Beijing 100055China Institute of Mountain Hazards and Environment CASChengdu 610041China

The impact force on retaining structure,which is caused by granular flow comprised of dry particles originated from shallow landslide failure,still lacks systematic *** order to support the potential design requirement of structure used to resist this kind of impact,a series of dry granular impact experiments are conducted on one rigid barrier *** to parametric analysis results,one nonlinear regression model is proposed to correlate total normal impact force at critical time(Fcr)with its influential ***,we complete a systematic statistics analysis and obtain a subsequent optimum regression equation based on the proposed *** to experience and dimension balance,the equation is modified and finally transformed into one non-dimensional equation,which shows good agreement between predicted and observed results.

关键词： Granular flow Impact force Rigid barrier

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Zero-oxidation state precursor assisted fabrication of highly dispersed and stable Pt catalyst for chemoselective hydrogenation ofα,β-unsaturated aldehydes

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Nano Research 2023年第5期16卷 6085-6093页

作者： Yu Liang Mark Douthwaite Xiaoyang Huang binbin zhao Qiong Tang Lei Liu Jinxiang Dong College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024China Cardiff Catalysis Institute School of ChemistryCardiff UniversityMain BuildingPark PlaceCardiffCF103ATUK

The chemoselective hydrogenation ofα,β-unsaturated aldehydes is a key strategy for the synthesis of fine ***,we developed an efficient method of depositing Pt particles on FeO_(x)/*** strategy is dependent on using a platinumdivinyltetramethyldisiloxane complex(Pt^(0)-DVTMS)as the precursor,which we demonstrate can be removed through a H_(2)-treatment under mild ***,in turn,allowed for the synthesis of catalysts with well dispersed Pt *** presence of FeO_(x) species also aided Pt dispersion;when coated onto SBA-15,FeO_(x) strongly interacted with dissociated Pt species,inhibiting both Pt aggregation and metal *** cinnamaldehyde as a modelα,β-unsaturated aldehyde,it was demonstrated that this catalyst was highly selective towards the unsaturated alcohol and no obvious loss in activity was observed over five *** catalyst was determined to be significantly more effective than an analogous catalyst prepared using chloroplatinic acid as a precursor,evidencing the importance of using the Pt0-DVTMS *** corroborate the excellent catalytic performance to highly dispersed Pt-species,whereby Pt0 and Pt^(2+) play a critical role in activating H_(2) and the C=O *** research demonstrates that the Pt precursor can have a significant impact on the physicochemical properties and thus,the performance of the final *** also evidences how metal support interactions can dramatically influence selectivity in such hydrogenation *** novel catalyst preparation protocol,using a DVTMS ligand for Pt impregnation,offers a facile approach to the design of multi-component heterogeneous catalysts.

关键词： platinum catalyst zero-oxidation state stability chemoselective hydrogenation α,β-unsaturated aldehydes

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Development of a Haploid-Inducer Mediated Genome Editing System for Accelerating Maize Breeding

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Molecular Plant 2019年第4期12卷 597-602页

作者： Baobao Wang Lei Zhu binbin zhao Yongping zhao Yurong Xie Zhigang Zheng Yaoyao Li Juan Sun Haiyang Wang Biotechnology Research Institute Chinese Academy of Agricultural Sciences Beijing 100081 China School of Life Sciences State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources South China Agricultural University Guangzhou 510642 China

Crop breeding aims to generate pure in bred lines with multiple desired traits. Doubled haploid (DH) and genome editing using CRISPR/Cas9 are two powerful game-changing technologies in crop breeding. However, both of them still fall short for rapid generation of pure elite lines with integrated favorable traits. Here, we report the development of a Haploid-Inducer Mediated Genome Editing (IMGE) approach, which utilizes a maize haploid inducer line carrying a CRISPR/Cas9 cassette targeting for a desired agronomic trait to pollinate an elite maize in bred line and to generate genome-edited haploids in the elite maize background. Homozygous pure DH lines with the desired trait improvement could be generated within two generations, thus bypassing the lengthy procedure of repeated crossing and backcrossing used in conventional breeding for integrating a desirable trait into elite commercial backgrounds.

关键词： maize, doubled haploids (DH) CRSIPR/Cas9 haploid-inducer mediated genome editing (IMGE) crop breeding

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Green-Naghdi Theory,Part A:Green-Naghdi(GN) Equations for Shallow Water Waves

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Journal of Marine Science and Application 2011年第3期10卷 253-258页

作者： William C. Webster Wenyang Duan binbin zhao Department of Civil ＆ Environmental Engineering University of California Berkeley CA 94720-1710 USA College of Shipbuilding Engineering Harbin Engineering University 150001 Harbin China

In this work, Green-Naghdi （GN） equations with general weight functions were derived in a simple way. A wave-absorbing beach was also considered in the general GN equations. A numerical solution for a level higher than 4 was not feasible in the past with the original GN equations. The GN equations for shallow water waves were simplified here, which make the application of high level （higher than 4） equations feasible. The linear dispersion relationships of the first seven levels were presented. The accuracy of dispersion relationships increased as the level increased. Level 7 GN equations are capable of simulating waves out to wave number times depth kd 〈 26. Numerical simulation of nonlinear water waves was performed by use of Level 5 and 7 GN equations, which will be presented in the next paper.

关键词： Green-Naghdi (GN) equations dispersion relation wave-absorbing beach shallow-water waves

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Towards Understanding the Security of Modern Image Captchas and Underground Captcha-Solving Services

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Big Data Mining and Analytics 2019年第2期2卷 118-144页

作者： Haiqin Weng binbin zhao Shouling Ji Jianhai Chen Ting Wang Qinming He Raheem Beyah College of Computer Science and Technology Zhejiang University Department of Computer Science and Engineering Lehigh University School of Electrical and Computer Engineering Georgia Institute of Technology

Image captchas have recently become very popular and are widely deployed across the Internet to defend against abusive programs. However, the ever-advancing capabilities of computer vision have gradually diminished the security of image captchas and made them vulnerable to attack. In this paper, we first classify the currently popular image captchas into three categories: selection-based captchas, slide-based captchas, and click-based captchas. Second, we propose simple yet powerful attack frameworks against each of these categories of image captchas. Third, we systematically evaluate our attack frameworks against 10 popular real-world image captchas,including captchas from ***, ***, and ***. Fourth, we compare our attacks against nine online image recognition services and against human labors from eight underground captcha-solving services. Our evaluation results show that(1) each of the popular image captchas that we study is vulnerable to our attacks;(2) our attacks yield the highest captcha-breaking success rate compared with state-of-the-art methods in almost all scenarios; and(3) our attacks achieve almost as high a success rate as human labor while being much *** on our evaluation, we identify some design flaws in these popular schemes, along with some best practices and design principles for more secure captchas. We also examine the underground market for captcha-solving services, identifying 152 such services. We then seek to measure this underground market with data from these services. Our findings shed light on understanding the scale, impact, and commercial landscape of the underground market for captcha solving.

关键词： image captchas captcha security captcha-solving service underground market

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Rock joint detection from borehole imaging logs using a convolutional neural networks model

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Journal of Earth Science 2024年

作者： Yunfeng Ge Geng Liu Haiyan Wang Huiming Tang binbin zhao Faculty of Engineering， China University of Geosciences Hunan Earthquake Agency Badong National Observation and Research Station of Geohazards， China University of Geosciences Research Institute of Transmission and Transformation Projects， China Electric Power Research Institute Co.， Ltd， State Grid Corporation of China

To map the rock joints in the underground rock mass， a method was proposed to semi-automatically detect the rock joints from borehole imaging logs using a deep learning algorithm. First， 450 images containing rock joints were selected from borehole ZKZ01 in the Rumei hydropower station. These images were labeled to establish ground truth which was subdivided into training， validation， and testing data. Second， the YOLO v2 model with optimal parameter settings was constructed. Third， the training and validation data were used for model training， while the test data was used to generate the Precision-Recall curve for prediction evaluation. Fourth， the trained model was applied to a new borehole ZKZ02 to verify the feasibility of the model. There were 12 rock joints detected from the selected images in borehole ZKZ02 and four geometric parameters for each rock joint were determined by sinusoidal curve fitting. The average precision of the trained model reached 0.87.

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An Integrated Multi-Level Early Warning Method for Rainfall-Induced Shallow Landslides

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Earthquake Research in China 2020年第1期34卷 136-156页

作者： zhao binbin KONG Xiao'ang OU Wenhao LIU Yi YANG Zhi Faculty of Engineering China University of GeosciencesWuhan 430074China China Electric Power Research Institute Co. Ltd.Beijing 100055China

Rainfall-induced landslides have occurred frequently in Southwestern China since the Wenchuan earthquake,resulting in massive loss of people’s life and ***,landslide early-warning is one of the most important tools for landslide hazard prevention and ***,the accumulation of historical data of the landslides induced by rainfall is limited in many remote mountain areas and the stability of the slope is easily affected by human engineering activities and environmental changes,leading to difficulties to accurately realize early warning of landslide hazards by statistical *** proposed warning method is divided into rainfall warning component and deformation warning component because the deformation induced by rainfall has the characteristic of hysteretic ***,tilted angle and crack width are chosen as monitoring *** grade level that contains rainfall intensity and duration information is graded according to the variation of the safety factor calculated by 3-D finite difference numerical simulation method,and then is applied using the strength reduction method and unascertained information theory to obtain the deformation grade level of several monitored ***,based on the system reliability theory,we establish a comprehensive landslide warning level method that provides four early warning levels to reflect the safety factor reductions during and post rainfall *** application of this method at a landslide site yield generally satisfactory results and provide a new method for performing multi-index and multi-level landslide early warnings.

关键词： Landslides Early warning Rainfall Deformation Unascertained degree theory

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