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Impact of EnKF assimilating Himawari-8 all-sky infrared radiance on the forecasting of a warm-sector rainstorm event

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Science china Earth sciences 2024年第10期67卷 3110-3127页

作者： Shanshan LOU Lei ZHU Xuexing QIU guangzhou CHEN Song YUAN Shengnan ZHOU Anhui Meteorological Observatory Hefei 230031China Key Laboratory of Meteorological Disaster Ministry of Education(KLME)Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Joint International Research Laboratory of Climate and Environment Change(ILCEC)Nanjing University of Information Science&TechnologyNanjing 210044China Huaihe River Basin Meteorological Center Hefei 230031China Shouxian National Climatology Observatory Huaihe River Basin Typical Farm Eco-Meteorological Experiment Field of CMAShouxian National Comprehensive Meteorological Observation Special Experimental OutfieldShouxian 232200China Anhui Province Key Laboratory of Atmospheric Science and Satellite Remote Sensing Hefei 230031China

Warm-sector rainstorms are highly localized events, with weather systems and triggering mechanisms are not obvious,leading to limited forecasting capabilities in numerical models. Based on the ensemble Kalman filter(PSU-En KF) assimilation system and the regional mesoscale model WRF, this study conducted a simulation experiment assimilating all-sky infrared(IR)radiance for a warm-sector rainstorm in East china and investigated the positive impact of assimilating the Himawari-8 moisture channel all-sky IR radiance on the forecast of the rainstorm. Results indicate that hourly cycling assimilation of all-sky IR radiance can significantly improve the forecast accuracy of this warm-sector rainstorm. There is a notable increase in the Threat Score(TS), with the simulated location and intensity of the 3-hour precipitation aligning more closely with observations. These improvements result from the assimilation of cloud-affected radiance, which introduces more mesoscale convective information into the model's initial fields. The adjustments include enhancements to the moisture field, such as increased humidity and moisture transport, and modifications to the wind field, including the intrusion of mid-level cold air and the strengthening of lowlevel convergent shear. These factors are critical in improving the forecast of this warm-sector rainstorm event.

关键词： Ensemble Kalman filter WRF model Himawari-8 All-sky radiance Warm-sector rainstorm

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A temporal framework for building up of healthy soils

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 292-296页

作者： Junling ZHANG Jiangzhou ZHANG Yunlong ZHANG guangzhou WANG State Key Laboratory of Nutrient Use and Management College of Resources and Environmental SciencesNational Academy of Agriculture Green DevelopmentChina Agricultural UniversityBeijing 100193China Inner Mongolia Key Laboratory of Soil Quality and Nutrient Resources College of GrasslandResources and EnvironmentInner Mongolia Agricultural UniversityHohhot 010018China Key Laboratory of Grassland Management and Utilization Ministry of Agriculture and Rural Affairs of the People’s Republic of ChinaCollege of Grassland Science and TechnologyChina Agricultural UniversityBeijing 100193China

Healthy soils are vital for the diverse services provided by ecosystems to human society~[1], such as provisioning(food,fiber, timber, and fuel), regulation(climate, disease, and natural hazards), waste treatment, nutrient cycling, and cultural services. Soil has a three phase system and the interactions between soil chemical, biological, and physical attributes determine functions(hydraulic, thermal, and gas fluxes).

关键词： soils soil cycling

Soils for food security

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 213-215页

作者： guangzhou WANG Qichao ZHU Junling ZHANG State Key Laboratory of Nutrient Use and Management National Academy of Agriculture Green DevelopmentCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China

Food security is among the most fundamental of national interests and productive farmland is essential for secure grain *** the increase of agricultural intensification and the impact of global climate change,the soil... 详细信息

关键词： farmland security earth

Identification and construction of Boolean functions with maximum algebraic immunity

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Science china(information sciences) 2010年第7期53卷 1379-1396页

作者： LIU MeiCheng, PEI DingYi & DU YuSong college of mathematics and information sciences, guangzhou university, guangzhou 510006, china college of mathematics and information sciences Guangzhou University

Boolean functions with maximum algebraic immunity have been considered as one class of cryptographically significant functions. It is known that Boolean functions on odd variables have maximum algebraic immunity if and only if a correlative matrix has column full rank, and Boolean functions on even variables have maximum algebraic immunity if and only if two correlative matrices have column full rank. Recently, a smaller matrix was used in the odd case. We find that one or two smaller matrices can be used in the even case and consequently present several sufficient and necessary conditions for Boolean functions with maximum algebraic immunity. This result advances the ability to identify whether Boolean functions on even variables achieve maximum algebraic immunity. We also present a construction algorithm for n-variable Boolean functions with maximum algebraic immunity, specially with the Hamming weights of ∑2 n i=0 -1 . It is easily realized for not too large n and helps construct balanced Boolean functions with maximum algebraic immunity on even variables. Furthermore, we present a sufficient and necessary condition for balanced Boolean functions to achieve maximum algebraic immunity and optimum algebraic degree, and modify the construction algorithm to con- struct Boolean functions on odd variables with maximum algebraic immunity, optimum algebraic degree and high nonlinearity.

关键词： Boolean functions MAI functions algebraic attacks algebraic immunity algebraic degree non-linearity

Construction of Boolean functions with maximum algebraic immunity and count of their annihilators at lowest degree

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Science china(information sciences) 2010年第4期53卷 780-787页

作者： DU YuSong* & PEI DingYi School of mathematics and information sciences, guangzhou university, guangzhou 510006, china School of mathematics and information sciences Guangzhou University

Boolean functions used in stream ciphers against algebraic attacks are required to have a necessary cryptographic property-high algebraic immunity (AI). In this paper, Boolean functions of even variables with the maximum AI are investigated. The number of independent annihilators at the lowest degree of Boolean functions of even variables with the maximum AI is determined. It is shown that when n is even, one can get an (n + 1)-variable Boolean function with the maximum AI from two n-variable Boolean functions with the maximum AI only if the Hamming weights of the two functions satisfy the given conditions. The nonlinearity of the Boolean functions obtained in this way is computed. Similarly, one can get an (n + 2)-variable Boolean function with the maximum AI from four n-variable Boolean functions with the maximum AI. The nonlinearity of a class of Boolean functions with the maximum AI is determined such that their Hamming weights are either the maximum or the minimum.

关键词： Boolean function algebraic attack algebraic immunity annihilator nonlinearity

Magmatic-hydrothermal Evolution and Mineralization Mechanisms of the Wangjiazhuang Cu(-Mo)Deposit in the Zouping Volcanic Basin,Shandong Province,china:Constraints from Fluid Inclusions

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 679-700页

作者： SHU Lei YANG Renchao SHEN Kun YANG Deping MAO guangzhou LI Min LIU Pengrui MA Xiaodong Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and TechnologyQingdaoShandong 266590China Key Laboratory of Gold Mineralization Processes and Resource Utilization MNR/Key Laboratory of Metallogenic Geological Processes and Resource UtilizationShandong Province/Shandong Institute of Geological SciencesJinan 250013China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdaoShandong 266237China

The Wangjiazhuang Cu(-Mo)deposit,located within the Zouping volcanic basin in western Shandong Province,china,is unique in this area for having an economic *** order to expound the metallogenetic characteristics of this porphyry-like hydrothermal deposit,a detailed fluid inclusion study has been conducted,employing the techniques of representative sampling,fluid inclusion petrography,microthermometry,Raman spectroscopy,LA-ICP-MS analysis of single fluid inclusions,as well as cathode fluorescence spectrometer analysis of host mineral *** deposit contains mainly two types of orebodies,***-dissemination-stockwork orebodies in the K-Si alteration zone and pegmatiticquartz sulfide veins above *** addition,minor breccia ore occurs *** types of fluid inclusions in the deposit and altered quartz monzonite are identified:L-type one-or two-phase aqueous inclusions,V-type vapor-rich inclusions with V/L ratios greater than 50%-90%,D-type multiphase fluid inclusions containing daughter minerals or solids and S-type silicate-bearing fluid inclusions containing mainly muscovite and *** petrography and fluid inclusion study has revealed a three-stage mineralization process,driven by magmatic-hydrothermal fluid activity,as ***,a hydrothermal fluid,separated from the parent magma,infiltrated into the quartz monzonite,resulting in its extensive K-Si alteration,as indicated by silicate-bearing fluid inclusions trapped in altered quartz *** is followed by the early mineralization,the formation of quartz veinlets and dissemination-stockwork *** the main mineralization stage,due to the participation and mixing of meteoric groundwater with magmatic-sourced hydrothermal fluid,the cooling and phase separation caused deposition of metals from the hydrothermal *** a result,the pegmatitic-quartz sulfide-vein ores *** the late mineralization stage,decreasing fluid salinity led to the formation of L-type aqueous

关键词： fluid inclusions fluid immiscibility mineralization mechanisms Wangjiazhuang Cu(-Mo)deposit

Saline-alkali soil reclamation and utilization in china:progress and prospects

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 216-228页

作者： guangzhou WANG Gang NI Gu FENG Haley MBURRILL Jianfang LI Junling ZHANG Fusuo ZHANG State Key Laboratory of Nutrient Use and Management(SKLNUM) College of Resources and Environmental SciencesNational Academy of Agriculture Green DevelopmentChina Agricultural UniversityBeijing 100193China The Institute of Ecology and Evolution University of OregonEugeneOR97403USA

Soil salinity is a global threat to the productivity of arable land. With the impact of population growth and development of social economy in china, the area of arable land has been shrinking in recent decades and is approaching a critical threshold of 120 Mha, the minimum area for maintaining the national food security. Saline-alkaline land, as important backup reserve, has been receiving increased attention as an opportunity to expand land resources. This review first summarizes the general principles and technologies of saline soil reclamation to support plant growth, including leaching salts or blocking the rise of salts, and soil fertility enhancement to improve the buffering *** the progress in this area in china is described including the customization of technologies and practices used in different saline-alkali regions. Following the soil management strategies, the concept of selecting crops for saline soil is proposed. This encompasses halophyte planting, salt-tolerant crop breeding and the application of saline-adapted functional microorganisms to improve the adaptation of crops. Finally, the current problems and challenges are evaluate, and future research directions and prospects proposed for managing this major soil constraint.

关键词： Food security land reserve reclamation saline-alkali soil utilization

A novel key pre-distribution scheme for wireless distributed sensor networks

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Science china(information sciences) 2010年第2期53卷 288-298页

作者： PEI DingYi 1 , DONG JunWu 1 & RONG ChunMing 2 1 college of mathematics and information Science, guangzhou university, guangzhou 510006, china 2 university of Stavanger, N-4036, Stavanger, Norway college of mathematics and information Science Guangzhou University university of Stavanger

A novel key pre-distribution scheme for sensor networks is proposed, which enables sensor nodes to communicate securely with each other using cryptographic techniques. The approach uses the rational normal curves in the projective space with the dimension n over the finite field F q . Both secure connectivity and resilience of the resulting sensor networks are analyzed. By choosing the parameters q and n properly, this key pre-distribution scheme has some advantages over the previous known schemes. In addition, if the number of the rational normal curves in the scheme becomes too large for an application, the size may be reduced by choosing a part of the curves randomly. This reduction has, shown by our experiments, only minimal impact on secure connectivity and resilience of the resulting sensor network.

关键词： sensor network key pre-distribution scheme combinatorial design rational normal curve projective space finite field

Entropy correction of BTZ black holes in a tunneling framework

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Science china(Physics,Mechanics & Astronomy) 2010年第8期53卷 1427-1433页

作者： ZHANG JingYi Center for Astrophysics, guangzhou university, guangzhou 510006, china guangzhou university Center for Astrophysics Guangzhou China (GRID:grid.411863.9) (ISNI:***)

In this paper, using the Parikh-Wilczek tunneling framework, we first calculate the emission rates of non-rotating BTZ black holes and rotating BTZ black holes to second order accuracy. Then, by assuming that the emission process satisfies an underlying unitary theory, we obtain the corrected entropy of the BTZ black holes. A log term emerges naturally in the expression of the corrected entropy. A discussion about the inverse area term is also presented.

关键词： Hawking radiation black hole tunneling black hole entropy correction quantum theory