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Spatial heterogeneity of the driving forces of cropland change in China

Science China Earth sciences 2005年第12期48卷 2231-2240页

作者： LIU Xuhua1,2, WANG Jinfeng1, LIU Mingliang4.1 & MENG Bin1,2,3 1. Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, China 2. Graduate school of the Chinese Academy of sciences, Beijing 100039, China 3. College of Arts and sciences of Beijing Union university, Beijing 100083, China 4. school of forestry and wildlife sciences, auburn university, auburn, alabama, al36849, usa 1. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate school of the Chinese Academy of sciences 100039 Beijing China 3. school of forestry and wildlife sciences Auburn University Auburn AL36849 Alabama USA 4. College of Arts and sciences of Beijing Union university 100083 Beijing China

By using digital satellite remote sensing data acquired in 1987―1989 and 1999―2000 and GIS combined with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in China. The results indicated that the cropland change in the study period was constrained by geographical factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of China, natural condition changes and geographical background were the main constraints and drivers, while in Eastern China, social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in China recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, China.

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Soil Inorganic Nitrogen and Microbial Biomass Carbon and Nitrogen Under Pine Plantations in Zhanggutai Sandy Soil

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Pedosphere 2008年第6期18卷 775-784页

作者： YU Zhan-Yuan CHEN Fu-Sheng ZENG De-Hui ZHAO Qiong CHEN Guang-Sheng Daqinggou Ecological Station Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 （China）. Life College Nanchang University Nanchang 330029 （China） Ecosystem sciences and Regional Analysis （ESRA） Lab. School of Forestry ＆Wildlife Science Auburn University Alabama 36849 （USA）

The dynamics of soil inorganic nitrogen （NH4.＋ -N and NO3^- -N） and microbial biomass carbon （Cmic） and nitrogen （Nmic） under 30-year-old fenced Pinus sylvestris L. var. mongolica Litvin （SF）, unfenced P. sylvestris L. var. mongolica Litvin （SUF）, and unfenced Pinus densiflora Siebold et Zucc. （DUF） plantations in the Zhanggutai sandy soil of China were studied during Apr. to Oct. 2004.by the in situ closed-top core incubation method. all mentioned C and N indices in each stand type fluctuated over time. The ranges of inorganic N, Cmic, and Nmic contents in the three stand types were 0.7-2.6, 4..0-128.9, and 5.4.15.2 μg g^-1, respectively. The average contents of soil NH4.＋ -N and Cmic under the three 30-year-old pine plantations were not different. However, soil NO3^ -N and total inorganic N contents decreased in the order of SUF ≥ SF ≥ DUF, the Nmic content was in the order of SF = SUF 〉 DUF, and the Cmic：Nmic ratio was in the order of SUF = DUF 〉 SF. Seasonal variations were observed in soil inorganic N, microbial biomass, and plant growth. These seasonal variations had certain correlations with microbe and plant N use in the soil, and their competition for NH4.＋ -N was mostly regulated by soil N availability. The influence of tree species on inorganic N and Nmic were mainly because of differences in litter quality. Lack of gazing decreased the Cmic：Nmic ratio owing to decreased carbon output and increased the ability of soil to supply N. The soil N supply under the P. sylvestris var. mongolica plantation was lower than under the P. densiflora plantation.

关键词： ecosystem management Horqin sandy land soil nitrogen availability Pinus densiflora Pinus sylvestris vat. mongoliea

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Efficient estimation for additive hazards regression with bivariate current status data

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Science China Mathematics 2012年第4期55卷 763-774页

作者： TONG XingWei 1,,HU Tao 2 & SUN JianGuo 3,4.1 school of Mathematical sciences,Beijing Normal university,Beijing 100875,China 2 school of Mathematical sciences,Capital Normal university,Beijing 10004.,China 3 school of Mathematics,Jilin university,Changchun 130012,China 4.Department of Statistics,university of Missouri,Columbia,MO 65211,usa 1. school of Mathematical sciences Beijing Normal University Beijing 100875 China2. School of Mathematical Sciences Capital Normal University Beijing 100048 China3. School of Mathematics Jilin University Changchun 130012 China4. Department of Statistics University of Missouri Columbia MO 65211 USA

This paper discusses efficient estimation for the additive hazards regression model when only bivariate current status data are available. Current status data occur in many fields including demographical studies and tumorigenicity experiments （Keiding, 1991; Sun, 2006） and several approaches have been proposed for the additive hazards model with univariate current status data （Linet M., 1998; Martinussen and Scheike, 2002）. For bivariate data, in addition to facing the same problems as those with univariate data, one needs to deal with the association or correlation between two related failure time variables of interest. For this, we employ the copula model and an efficient estimation procedure is developed for inference. Simulation studies are performed to evaluate the proposed estimates and suggest that the approach works well in practical situations. An illustrative example is provided.

关键词： bivariate current status data copula model counting processes efficient estimation joint survivalfunction

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Adaptive Cloud Intrusion Detection System Based on Pruned Exact Linear Time Technique

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Computers, Materials & Continua 2024年第6期79卷 3725-3756页

作者： Widad Elbakri Maheyzah Md.Siraj Bander ali Saleh al-rimy Sultan Noman Qasem Tawfik al-Hadhrami Faculty of Computing Universiti Teknologi MalaysiaJohor BahruJohor81310Malaysia Computer Science Department College of Computer and Information SciencesImam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11432Saudi Arabia school of Science and Technology Nottingham Trent UniversityNottinghamNG118NSUK

Cloud computing environments,characterized by dynamic scaling,distributed architectures,and complex work-loads,are increasingly targeted by malicious *** threats encompass unauthorized access,data breaches,denial-of-service attacks,and evolving malware *** security solutions often struggle with the dynamic nature of cloud environments,highlighting the need for robust Adaptive Cloud Intrusion Detection Systems(CIDS).Existing adaptive CIDS solutions,while offering improved detection capabilities,often face limitations such as reliance on approximations for change point detection,hindering their precision in identifying *** can lead to missed attacks or an abundance of false alarms,impacting overall security *** address these challenges,we propose ACIDS(Adaptive Cloud Intrusion Detection System)-*** novel Adaptive CIDS framework leverages the Pruned Exact Linear Time(PELT)algorithm and a Support Vector Machine(SVM)for enhanced accuracy and ***-PELT comprises four key components:(1)Feature Selection:Utilizing a hybrid harmony search algorithm and the symmetrical uncertainty filter(HSO-SU)to identify the most relevant features that effectively differentiate between normal and anomalous network traffic in the cloud environment.(2)Surveillance:Employing the PELT algorithm to detect change points within the network traffic data,enabling the identification of anomalies and potential security threats with improved precision compared to existing approaches.(3)Training Set:Labeled network traffic data forms the training set used to train the SVM classifier to distinguish between normal and anomalous behaviour patterns.(4.Testing Set:The testing set evaluates ACIDS-PELT’s performance by measuring its accuracy,precision,and recall in detecting security threats within the cloud *** evaluate the performance of ACIDS-PELT using the NSL-KDD benchmark *** results demonstrate that ACIDS-PELT outperf

关键词： Adaptive cloud IDS harmony search distributed denial of service(DDoS) PELT machine learning SVM ISOTCID NSL-KDD

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Split-plot designs with general minimum lower-order confounding

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Science China Mathematics 2010年第4期53卷 939-952页

作者： WEI Jialin 1,4.YANG JianFeng 1,LI Peng 3 & ZHANG RunChu 1,2,1 school of Mathematical sciences and LPMC,Nankai university,Tianjin 300071,China 2 KLAS and school of Mathematics and Statistics,Northeast Normal university,Changchun 130024.China 3 school of Mathematical sciences,Capital Normal university,Beijing 100037,China 4.school of sciences,Tianjin university of Commerce,Tianjin 300134.China 1. school of Mathematical sciences and LPMC Nankai University Tianjin 300071 China4. School of Sciences Tianjin University of Commerce Tianjin 300134 China3. School of Mathematical Sciences Capital Normal University Beijing 100037 China2. KLAS and School of Mathematics and Statistics Northeast Normal University Changchun 130024 China

Split-plot designs have been widely used in industrial *** to now,most methods for choosing this kind of designs are based on the minimum aberration (MA) ***,by introducing a new pattern,called aliased effect-number pattern (AENP),Zhang et *** a general minimum lowerorder confounding (denoted by GMC for short) criterion and established a general minimum confounding (also denoted by GMC for saving notations) *** is proved that,the GMC criterion selects optimal designs in a more elaborate manner than the existing ones,and when an experimenter has a prior about the importance ordering of factors in experiments the GMC designs are better than other optimal *** this paper we extend the GMC criterion to the split-plot design case and give a GMC-FFSP criterion for ranking split-plot *** comparisons of the new criterion with the MA-MSA-FFSP criterion are given,and the optimal 32-run split-plot designs up to 14.factors under the two criteria are tabulated for comparison and application.

关键词： fractional factorial design GMC criterion minimum aberration split-plot

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Customized Convolutional Neural Network for Accurate Detection of Deep Fake Images in Video Collections

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Computers, Materials & Continua 2024年第5期79卷 1995-2014页

作者： Dmitry Gura Bo Dong Duaa Mehiar Nidal al Said Department of Cadastre and Geoengineering Kuban State Technological UniversityKrasnodar350072Russian Federation Department of Geodesy Kuban State Agrarian UniversityKrasnodar350072Russian Federation school of Innovation and Entrepreneurship Liaoning UniversityLiaoning110031China Department of IT Middle East UniversityAmman11831Jordan College of Mass Communication Ajman UniversityP.O Box 346AjmanUnited Arab Emirates

The motivation for this study is that the quality of deep fakes is constantly improving,which leads to the need to develop new methods for their *** proposed Customized Convolutional Neural Network method involves extracting structured data from video frames using facial landmark detection,which is then used as input to the *** customized Convolutional Neural Network method is the date augmented-based CNN model to generate‘fake data’or‘fake images’.This study was carried out using Python and its *** used 24. films from the dataset gathered by the Deep Fake Detection Challenge,of which 199 were made up and the remaining 53 were *** seconds were allotted for each *** were 318 videos used in all,199 of which were fake and 119 of which were *** proposedmethod achieved a testing accuracy of 91.4.%,loss of 0.34.,and AUC score of 0.92,outperforming two alternative approaches,CNN and ***,our method succeeded in greater accuracy than contemporary models such as XceptionNet,Meso-4.EfficientNet-BO,MesoInception-4.VGG-16,and *** novelty of this investigation is the development of a new Convolutional Neural Network(CNN)learning model that can accurately detect deep fake face photos.

关键词： Deep fake detection video analysis convolutional neural network machine learning video dataset collection facial landmark prediction accuracy models

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Tuning the reactivity of TiO_(2)layer with uniform distribution of Sub-5 nm Fe_(2)O_(3)particles via in situ voltage-assisted oxidation for robust catalytic reduction

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Nano Materials Science 2024年第2期6卷 223-234页

作者： Nisa Nashrah Abdelkarim Chaouiki Wail al Zoubi Young Gun Ko Integrated Materials Chemistry Laboratory School of Materials Science and EngineeringYeungnam UniversityGyeongsan38541Republic of Korea

The trade-off between efficiency and stability has limited the application of TiO_(2)as a catalyst due to its poor surface ***,we present a modification of a TiO_(2)layer with highly stable Sub-5 nm Fe_(2)O_(3)nanoparticles(NP)by modulating its structure-surface reactivity relationship to attain efficiency-stability balance via a voltage-assisted oxidation *** situ simultaneous oxidation of the Ti substrate and Fe precursor using high-energy plasma driven by high voltage resulted in uniform distribution of Fe_(2)O_(3)NP embedded within porous TiO_(2)*** surface characterizations with density functional theory demonstrated an improved electronic transition in TiO_(2)due to the presence of surface defects from reactive oxygen species and possible charge transfer from Ti to Fe;it also unexpectedly increased the active site in the TiO_(2)layer due to uncoordinated electrons in Sub-5 nm Fe_(2)O_(3)NP/TiO_(2)catalyst,thereby enhancing the adsorption of chemical functional groups on the *** unique embedded structure exhibited remarkable improvement in reducing 4.nitrophenol to 4.aminophenol,achieving approximately 99%efficiency in 20 min without stability decay after 20 consecutive cycles,outperforming previously reported TiO_(2)-based *** finding proposes a modified-electrochemical strategy enabling facile construction of TiO_(2)with nanoscale oxides extandable to other metal oxide systems.

关键词： Titanium dioxide Oxide nanoparticle Electrochemical oxidation Surface reactivity Efficiency Stability

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Analysis and application of automatic deformation monitoring data for buildings and structures of mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 516-522页

作者： XIAO Jie1, 2, 3, ZHANG Jin4.1. Institute of Geodesy and Geophysics, Chinese Academy of sciences, Wuhan 4.0077, China 2. Key Laboratory of Dynamic Geodesy, Institute of Geodesy and Geophysics, Chinese Academy of sciences, Wuhan 4.0077, China 3. Graduate school of Chinese Academy of sciences, Beijing 10004., China 4. Department of Surveying and Mapping, Taiyuan {4. of Technology, Taiyuan 030024. China Taiyuan Univ Technol Dept Surveying & Mapping Taiyuan 030024 Peoples R China Chinese Acad Sci Inst Geodesy & Geophys Key Lab Dynam Geodesy Wuhan 430077 Peoples R China Chinese Acad Sci Grad Sch Beijing 100049 Peoples R China

The buildings and structures of mines were monitored automatically using modern surveying technology. Through the analysis of the monitoring data, the deformation characteristics were found out from three aspects containing points, lines and regions, which play an important role in understanding the stable state of buildings and structures. The stability and deformation of monitoring points were analysed, and time-series data of monitoring points were denoised with wavelet analysis and Kalman filtering, and exponent function and periodic function were used to get the ideal deformation trend model of monitoring points. Through calculating the monitoring data obtained, analyzing the deformation trend, and cognizing the deformation regularity, it can better service mine safety production and decision-making.

关键词： wavelet analysis Kalman filtering deformation monitoring data analysis mine

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Origin of the synergistic effects of bimetallic nanoparticles coupled with a metal oxide heterostructure for accelerating catalytic performance

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SusMat 2024年第3期4卷 227-239页

作者： Wail al Zoubi Abdullah al Mahmud Farah Hazmatulhaq Mohammad R.Thalji Stefano Leoni Jee-Hyun Kang Young Gun Ko Integrated Materials Chemistry Laboratory School of Materials Science and EngineeringYeungnam UniversityGyeongsanRepublic of Korea school of Chemical Engineering Yeungnam University280 Daehak-roGyeongsanGyeongbukRepublic of Korea Korea Institute of Energy Technology(KENTECH) 200 Hyeokshin-roJeollanam-doNajuRepublic of Korea Cardiff university School of ChemistryCF103AT CardiffUnited Kingdom

Precisely tuning bicomponent intimacy during reactions by traditional methods remains a formidable challenge in the fabrication of highly active and stable catalysts because of the difficulty in constructing well-defined catalytic systems and the occurrence of agglomeration during *** overcome these limitations,a PtRuPNiO@TiO_(x)catalyst on a Ti plate was prepared by ultrasound-assisted low-voltage plasma *** method involves the oxidation of pure Ti metal and co-reduction of strong metals at 3000◦C,followed by sonochemical ultrasonication under ambient conditions in an aqueous *** intimacy of the bimetals in PtRuPNiO@TiOx is tuned,and the metal nanoparticles are uniformly distributed on the porous titania coating via strong metal-support interactions by leveraging the instantaneous high-energy input from the plasma discharge and ultrasonic *** intimacy of PtRuPNiO@TiO_(x)increases the electron density on the Pt ***,the paired sites exhibit a high hydrogen evolution reaction activity(an overpotential of 220 mV at a current density of 10 mA cm^(−2)and Tafel slope of 186 mV dec^(−1)),excellent activity in the hydrogenation of 4.nitrophenol with a robust stability for up to 20 cycles,and the ability to contrast stated catalysts without ultrasonication and plasma *** study facilitates industrially important reactions through synergistic chemical interactions.

关键词： bimetals nanoparticles oxides heterostructures hydrogenation

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The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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Science China Earth sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2, CAI Qiangguo1, YUE Zhongqi3, LU Zhongchen4. LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic sciences and Natural Resources Re-search, Chinese Academy of sciences, Beijing 100101, China 2. Institute of forestry, Chinese Academy of forestry sciences, Beijing 100091, China 3. Department of Civil Engineering, university of Hong Kong, Hong Kong, China 4. Eco-environmental Research Center, Chinese Academy of sciences, Beijing 100085, China 5. College of Resources and Environment, Southwest Agricultural university, Chongqing 4.0716, China Correspondence should be addressed to Chen Hao 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Institute of forestry Chinese Academy of Forestry Sciences 100091 Beijing China 3. Department of Civil Engineering University of Hong Kong Hong Kong China 4. Eco-environmental Research Center Chinese Academy of Sciences 100085 Beijing China 5. College of Resources and Environment Southwest Agricultural University 400716 Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 530 mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4. less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2, it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 30%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

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