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INTEGRAL-TYPE TESTS FOR GOODNESS-OF-FIT

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Journal of Systems Science & Complexity 2010年第4期23卷 784-795页

作者： junjian zhang Guoying LI College of Mathematics Guangxi Normal University Guilin 541004 China College of Applied Sciences Beijing University of Technology Beijing 100124 China Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

A family of integral-type goodness-of-fit tests is investigated. This family includes some existing tests, such as the Cramer-von Mises test and Anderson-Darling test, etc. The asymptotic distributions of the tests in the family under the null and local alternative hypotheses are established. The almost sure convergence under a fixed underlying distribution is obtained. Furthermore, simulations are conducted to compare the powers of the tests in the family. Simulation results show that for different alternatives, the more powerful tests are different, and the parameter ）, has great influence on the tests in small sample cases.

关键词： Asymptotic distribution goodness-of-fit integral-type tests power comparison.

SUMMATION OF ABSOLUTE VALUE TEST FOR MULTIPLE OUTCOME COMPARISON WITH MODERATE EFFECT

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Journal of Systems Science & Complexity 2013年第3期26卷 462-469页

作者： LI Zhengbang CAO Fan zhang junjian LI Qizhai School of Mathematics and Statistics Wuhan University Guangxi Normal University Academy of Mathematics and Systems Science Chinese Academy of Sciences

In biomedical research,in order to evaluate the effect of a drug,investigators often need to compare the differences between one treatment group and another one by using multiple *** rank-sum tests can handle the case where the outcome differences between two groups are in the same *** they are not,MAX can handle it and is very useful when one/some of the differences is/are relatively larger than the *** the individual outcome difference between two groups is moderate,a new method,summation of the absolute value of rank-based test for each outcome,is proposed in this *** comparison with the existing methods based on simulation studies and a real example show that the proposed test is a robust test,and works well when the difference for each outcome is *** authors also derive some theoretical results for comparing the power between MAX and the the proposed method.

关键词： Absolute value generalized inverse multiple outcomes rank-sum test

Rethinking multi-spatial information for transferable adversarial attacks on speaker recognition systems

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CAAI Transactions on Intelligence Technology 2024年第3期9卷 620-631页

作者： junjian zhang Hao Tan Le Wang Yaguan Qian Zhaoquan Gu Guangzhou University GuangzhouChina Department of New Networks Peng Cheng LaboratoryShenzhenChina Harbin Institute of Technology(Shenzhen) ShenzhenChina Zhejiang University of Science and Technology HangzhouChina

Adversarial attacks have been posing significant security concerns to intelligent systems,such as speaker recognition systems(SRSs).Most attacks assume the neural networks in the systems are known beforehand,while black-box attacks are proposed without such information to meet practical *** black-box attacks improve trans-ferability by integrating multiple models or training on multiple datasets,but these methods are *** by the optimisation strategy with spatial information on the perturbed paths and samples,we propose a Dual Spatial Momentum Iterative Fast Gradient Sign Method(DS-MI-FGSM)to improve the transferability of black-box at-tacks against ***,DS-MI-FGSM only needs a single data and one model as the input;by extending to the data and model neighbouring spaces,it generates adver-sarial examples against the integrating *** reduce the risk of overfitting,DS-MI-FGSM also introduces gradient masking to improve *** authors conduct extensive experiments regarding the speaker recognition task,and the results demonstrate the effectiveness of their method,which can achieve up to 92%attack success rate on the victim model in black-box scenarios with only one known model.

关键词： speaker recognition spoofing attacks

Volume and Surface Distribution Heterogeneity of Nano-pore in Coal Samples by CO2 and N2 Adsorption Experiments

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Acta Geologica Sinica(English Edition) 2020年第5期94卷 1662-1675页

作者： zhang junjian WEI Chongtao LUO Jinhui LU Guanwen QUAN Fangkai ZHENG Kai PENG Yujie College of Earth Sciences&Engineering Shandong University of Science and TechnologyQingdaoShandong 266590China School of Resources and Earth Science China University of Mining and TechnologyXuzhouJiangsu 221116China Construction Equipment College Guizhou Polytechnic of ConstructionGuiyang 551400China

In this paper,the heterogeneity of adsorption pores in middle and high rank coal samples were analyzed by using low temperature N2 and CO2 adsorption technology and fractal *** following results were achieved.1)According to the results of volume and surface fractal dimension,meso-pores can be classified into Mep-1,Mep-2,and Mep-3,***-pore can be classified into Mip-1,Mip-2,and Mip-3,respectively.2)Pore types play an important role in affecting the heterogeneity of *** volume heterogeneity(VHY)of Mep-1 is simpler than that of Mep-2 and Mep-3 in type A ***,the VHY of Mep-1 becomes gradually larger than that of Mep-2 and Mep-3 from type A to type B and *** VHY of open pore in the same diameter is higher than that of semi-open or closed ***,the surface heterogeneity(SHY)of types A and B samples is significantly larger than that of type C,the SHY of semi-open or closed pores is more complicated than that of open pores.3)Coal rank mainly affects the heterogeneity of *** heterogeneity of type A is always smaller than that of type B and *** VHY of Mip-1 is more complicated than that of Mip-2 and Mip-3 in the same samples,and the sensitivity of the VHY of Mip-1 and Mip-2 to the degree of coal rank is smaller than that of ***,the SHY of Mip-1 and Mip-2 is simpler than that of Mip-3 in the same sample,the SHY of micro-pores remains stable as the pore size decreases,and the affect of coalification level on SHY decreases with the decrease in pore ***-scale fractal characterization has enabled quantitative characterization of adsorption pore properties and provided useful information with regards to the similarity of pore features in different coal reservoirs.

关键词： pore volume and surface fractal dimension adsorption pore middle and high rank coal western Guizhou and eastern Yunnan area

Characteristics and classification of paleozoic tight reservoirs in the central uplift of the South Yellow Sea Basin

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Energy Geoscience 2022年第4期3卷 383-393页

作者： Yumao Pang Xingwei Guo Xiangchun Chang junjian zhang Jingqi Zhou Laixing Cai Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and TechnologyQingdaoShandong266590China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdaoShandong266237China Qingdao Institute of Marine Geology QingdaoShandong266071China Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of SciencesQingdaoShandong266071China

Several sets of Paleozoic tight reservoirs are developed in the Central Uplift of the South Yellow Sea Basin.A qualitative analysis of the microscopic pore structure of the tight reservoir rocks was carried out through cast thin slice and scanning electron microscopic image *** on reservoir pet-rophysical properties,thirty core samples in the Central Uplift of the South Yellow Sea Basin were selected for high-pressure mercury intrusion(HPMI)analysis,which was then combined with fractal calculation to classify and evaluate the tight *** analysis of the HPMI curves and related parameters shows that the Paleozoic tight reservoirs can be divided into three types:Type-A,Type-B and ***-A sandstone reservoirs contain pores with size mostly ranging between 0.01 and 0.1 mm,followed by pores with size range of 0.001-0.01 m m,and relatively fewer pores larger than 0.1 m *** Type-B reservoirs are carbonate rocks with extremely heterogeneous pore size distribution,which is closely related to the development of dissolution pores and ***-C sandstone reservoirs are dominated by nanopores and submicron pores that distribute more heterogeneously than pores in Type-A *** pore distribution in sandstone reservoirs shows significant fractal characteristics and is closely related to the pore *** heterogeneity of nanopore distribution has a negative cor-relation with porosity and median pressure and a relatively weak correlation with *** study has important implications for petroleum exploration in the South Yellow Sea Basin.

关键词： South Yellow Sea Basin Tight reservoir High-pressure mercury injection Fractal characteristics

Pore-Fracture Distribution Heterogeneity of Shale Reservoirs Determined by using HPMI and LPN_(2 )GA Tests

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Acta Geologica Sinica(English Edition) 2022年第5期96卷 1659-1672页

作者： zhang junjian QIN Zhengyuan HAN Yanning WANG Huaimeng HOU Maoguo YAN Gaoyuan FENG Guangjun zhang Xiaoyang YIN Tingting zhang Hainan WEN Shupeng College of Earth Sciences&Engineering Shandong University of Science and TechnologyQingdaoShandong 266590China School of Resources and Earth Science China University of Mining and TechnologyXuzhouJiangsu 221116China Nottingham Geospatial Institute Faculty of EngineeringUniversity of NottinghamNottinghamNG72TUUK The First Exploration Team of Shandong Province Coal Geology Bureau ShandongQingdaoShandong 266000 General Institute of Chemical Geology Survey of CCGMB Beijing 100013China School of Geosciences China’s University of Petroleum(East China)QingdaoShandong 266580China 113 Team of Guizhou Coal Geology Bureau Guiyang 550000China

The compressibility of shale matrix reflects the effects of reservoir lithology, material composition, pore structure and tectonic deformation. It is important to understand the factors that influence shale matrix compressibility(SMC) and their effects on pore size distribution(PSD) heterogeneity in order to evaluate the properties of unconventional *** this study, the volumes of pores whose diameters were in the range 6–100 nm were corrected for SMC for 17 shale samples from basins in China using high-pressure mercury intrusion and low-temperature nitrogen gas adsorption analyses,in order to investigate the factors influencing the SMC values. In addition, the variations in fractal dimensions before and after pore volume correction were determined, using single and multifractal models to explain the effects of SMC on PSD heterogeneity. In this process, the applicability of each fractal model for characterizing PSD heterogeneity was determined using statistical analyses. The Menger and Sierpinski single fractal models, the thermodynamic fractal model and a multifractal model were all used in this study. The results showed the following. The matrix compression restricts the segmentation of the fractal dimension curves for the single fractal Menger and Sierpinski models, which leads to a uniformity of PSD heterogeneity for different pore diameters. However, matrix compression has only a weak influence on the results calculated using a thermodynamic model. The SMC clearly affects the multifractal value variations, showing that the fractal dimension values of shale samples under matrix compression are small. Overall PSD heterogeneity becomes small for pores with diameters below 100 nm and the SMC primarily affects the PSD heterogeneity of higher pore volume areas. The comparison of fractal curves before and after correction and the variance analysis indicate that the thermodynamic model is applicable to quantitatively characterize PSD heterogeneity of shale col

关键词： shale reservoirs matrix compressibility pore structure fractal dimension multifractal

Methane adsorption effected by pore structure of overmature continental shale:Lower Cretaceous Shahezi Formation,Xujiaweizi Fault,Songliao Basin

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Frontiers of Earth Science 2024年第1期18卷 172-187页

作者： Pengfei zhang Shuangfang LU Nengwu ZHOU Zizhi LIN Xiangchun CHANG junjian zhang Guo CHEN Yumao PANG Junjie WANG Hongsheng HUANG Qi ZHI College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Sanya Offshore Oil&Gas Research Institute Northeast Petroleum UniversitySanya 572025China School of Geoscience China University of Petroleum(East China)Qingdao 266580China College of Resources and Environment Yangtze UniversityWuhan 430100China

Overmature continental shale is commonly developed,but few studies have given insight into its pore structure and sorption *** techniques,including SEM,helium porosity and permeability,N_(2)/CO_(2)adsorption,MICP,and NMR,were used to detect the pore structure of shale from the Shahezi Formation,Xujiaweizi Fault,Songliao *** excess methane adsorption volumes were measured by the volumetric method and modeled by the Langmuir *** on the findings,the most developed pores are intraparticle pores in clay minerals,followed by the dissolution pores in feldspar,but organic pores are *** selected shales have low helium porosity(mean 1.66%)and ultralow permeability(mean 0.0498×10^(−3)μm^(2)).The pore throats are at the nanoscale,and the pore-throat size distributions are unimodal,with most less than 50 *** studied shales are characterized by the lower specific surface area(SSA)and pore volume(PV)but the larger average pore *** total SSA is contributed by the micro-and mesopores,while the PV is dominated by meso-and *** pore structures are more complex and controlled by multiple factors,such as mineral compositions and diagenesis,but organic matter is not *** maximum absolute adsorption methane volume(VL)is 0.97−3.58 cm^(3)/g(mean 1.90 cm^(3)/g),correlating well with the total SSA,SSA,and pore volume of micropores,which indicates that methane is mainly adsorbed and stored in micropores,followed by mesopores.

关键词： continental shale pore structure methane adsorption Shahezi Formation Songliao Basin

Assessing site-safeguard effectiveness and habitat preferences of Bar-headed Geese (Anser indicus) at their stopover sites within the Qinghai-Tibet Plateau using GPS/ GSM telemetry

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Avian Research 2020年第4期11卷 433-445页

作者： junjian zhang Yanbo Xie Laixing Li Nyambayar Batbayar Xueqin Deng Iderbat Damba Fanjuan Meng Lei Cao Anthony David Fox State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China Northwest Institute of Plateau Biology Chinese Academy of SciencesXining 810008China Wildlife Science and Conservation Center B-802 Union BuildingSukhbaatar DistrictUlaanbaatar 14210Mongolia Institute of Biology Mongolian Academy of SciencesUlaanbaatar 13330Mongolia Department of Bioscience Aarhus UniversityKaløGrenåvej 14DK-8410 RøndeDenmark

Background:The Bar-headed Goose(Anser indicus)breeds across the high plains and plateau of Central Asia and winters in the Qinghai-Tibet Plateau(QTP),the Yunnan-Guizhou Plateau and the Indian *** the two recognized discrete flyways of the Bar-headed Goose,the Eastern Tibetan Flyway(ETF)is the larger,comprising at least six migration ***,we remain ignorant about their migratory connectivity,habitat use and effectiveness of site-safeguard mechanisms set in place for the ***:We tracked 30 ETF Bar-headed Geese from Chinese and Mongolian breeding areas to their wintering grounds using GPS/GSM transmitters,to determine their migration routes and stopover staging patterns within the QTP,overlaying these upon GIS layers of protected area status and habitat type,to model their habitat ***:In total,14 tagged Bar-headed Geese provided information on their entire autumn migration and 4 geese on their entire spring *** Lake marked birds overwintered in the QTP(n=2),geese tagged in Mongolia wintered either in the QTP(n=3)or in India/Bangladesh(n=9),representing three of the migration routes within the *** total,tagged birds staged at 79 different stopover sites within QTP in autumn and 23 in spring,of which 65%(autumn)and 59%(spring)of all fixes fell within the boundaries of either National Nature Reserves(NNRs)or Important Birds Areas(IBAs)in the ***-headed Geese predominantly occurred on four land-cover types:grassland(mostly by day),water bodies(at night),wetlands and bare substrates(salt flats,dry lake/river substrates and plough)with little change in *** linear mixed models comparing presence with pseudo-absence data suggested geese strongly selected for wetlands as staging habitat,avoiding bare substrates in ***:Based on our limited observations of these tagged geese,this study is the first to show that the current designated National Nature Reserves in place in the stag

关键词： Anser indicus Bar-headed goose Habitat use Habitat selection Important bird area National nature reserve

Seasonal and regional differences in migration patterns and conservation status of Swan Geese(Anser cygnoides)in the East Asian Flyway

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Avian Research 2021年第4期12卷 477-490页

作者： Iderbat Damba junjian zhang Kunpeng Yi Huashan Dou Nyambayar Batbayar Tseveenmyadag Natsagdorj Batmunkh Davaasuren Lei Cao Anthony David Fox State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Institute of Biology Mongolian Academy of SciencesUlaanbaatar 13330Mongolia Hulun Lake National Nature Reserve Administration Inner Mon-golia 021008China Wildlife Sciences and Conservation Center of Mongolia Union BuildingB-701UNESCO Str.Ulaanbaatar 14210Mongolia Depart-ment of Ecoscience Aarhus UniversityAarhusDenmark.

Background:The Swan Goose(Anser cygnoides)breeds across Mongolia and adjacent China and Russia and winters exclusively in *** is globally threatened,showing long-term major range contractions and declining abundance,linked to habitat loss and *** remain ignorant about the biogeographical subpopulation structure of the species and potential differences in their migration timing,stopovers and schedules,information that could be vital to effective conservation of different elements of the species population,which we address here with results from a telemetry ***:In 2017-2018,we attached GPS/GSM telemetry devices to 238 Swan Geese on moulting sites in three discrete parts of their summering area(Dauria International Protected Area,Central Mongolia and Western Mongolia),generating 104 complete spring and autumn migration episodes to compare migration speed and nature between birds of different summer ***:Birds from all three breeding areas used almost completely separate migration routes to winter sympatrically in the Yangtze River *** many features of the spring and autumn migrations of the three groups were similar,despite the significantly longer migration routes taken by Western Mongolian tagged birds,birds from Dauria Region arrived significantly later in winter due to prolonged staging in coastal areas and took longer to reach their breeding areas in *** birds of all breeding provenances,spring migration was approximately twice as fast as autumn *** used by staging Swan Geese(mainly wetlands)in autumn and spring almost never fell within national level protected areas,suggesting major site safeguard is necessary to protect these critical ***:This study showed the discreteness of migration routes taken by birds of different summer provenances and differences in their migratory patterns,highlighting key staging areas(Yalu River Estuary in China/North Korea for Dauria Region br

关键词： Anser cygnoides GPS/GSM telemetry Migration parameters Segmentation Stopover duration Swan Geese