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Atmospheric Sulfur Deposition on Farmland in East China

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Pedosphere 2005年第1期15卷 120-128页

作者： WANGTi-Jian YANGHao-Ming GAOLi-Jie ZHANGYan HUZheng-Yi XUCheng-Kai DepartmentofAtmosphericScience NanjingUniversityNanjing210093China DepartmentofAtmosphericScience NanjingUniversityNanjing210093China／／KeyLaboratoryofMeteorologicalDisasterandEnvironmentalVariationNanjingInstituteofMeteorologyNanjing210044China StateKeyLaboratoryofSoilandSustainableAgriculture InstituteofSoilScienceChineseAcademyofScienceNanjing210008China

Atmospheric sulfur deposition onto typical farmland in East China was investigated using both field measurements and numerical modeling. The field measurements were conducted at the Experiment Station of Red Soil Ecology, Chinese Academy of Sciences, 10 km from Yingtan, Jiangxi Province, East China, between November 1998 and October 1999, and at the Changshu Ecological Experiment Station, Chinese Academy of Sciences, in a rapidly developing region of Jiangsu Province, East China, between April 2001 and Marc…

关键词： atmospheric sulfur deposition East China farmland

Total control-based unified allocation model for allowable basin water withdrawal and sewage discharge

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Science China(Technological Sciences) 2010年第5期53卷 1387-1397页

作者： HU SiYi1,2,WANG ZongZhi1,WANG YinTang1 & ZHANG LingLing3.1 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,nanjing Hydraulic Research institute,nanjing 210029,China 2 Ministry of Water Resources,the People’s Republic of China,Beijing 100053.China 3.School of Public Administration,HoHai University,nanjing 210098,China 1. State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute Nanjing 210029 China2. Ministry of Water Resources the People’s Republic of China Beijing 100053 China3. School of Public Administration HoHai University Nanjing 210098 China

In this paper,a new model with a total amount control target of allowable water withdrawal based on initial water right is built for the implementation of initial water right allocation scheme as well as unified allocation for allowable water withdrawal and sewage *** model couples the water allocation simulation model and the computational model of permissible pol-lution bearing *** view of the model complexity,a new technology which synthesizes system simulation,iterative reservoir turns and intelligent computation is proposed to improve the operability of allocation scheme and computational *** the Beijiang River Basin in the Pearl River Basin as an example,the study explains the model establishment,solution and application,and draws an optimized operation graph of large-scale *** study also obtains a long-term operation strategy of river basin water resources system,the allocation schemes of allowable water withdrawal and sewage discharge in a typical year and the flow hydrographs of trans-boundary *** validity of the model and the allocation rationality are analyzed as well.

关键词： water resources management total control unified control of water withdrawal and sewage discharge optimized regulation integration technology

Paddy Soil Stability and Mechanical Properties as Affected by Long-Term Application of Chemical Fertilizer and Animal Manure in Subtropical China

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Pedosphere 2007年第5期17卷 568-579页

作者： LI Jiang-Tao ZHANG Bin School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 （China） institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）

Wet stability, penetration resistance （PR）, and tensile strength （TS） of paddy soils under a fertilization experiment for 22 years were determined to elucidate the function of soil organic matter in paddy soil stabilization. The treatments included no fertilization （CK）, normal chemical fertilization （NPK）, double the NPK application rates （2NPK）, and NPK mixed with organic manure （NPK＋OM）. Compared with CK, Fertilization increased soil organic carbon （SOC） and soil porosity. The results of soil aggregate fragmentation degree （SAFD） showed that fast wetting by water was the key fragmentation mechanism. Among the treatments, the NPK＋OM treatment had the largest size of water-stable aggregates and greatest normal mean weight diameter （NMWD）（P ≤ 0.05）, but the lowest PR and TS in both cultivated horizon （Ap） and plow pan. The CK and 2NPK treatments were measured with PR 〉 2.0 MPa and friability index 〈 0.20, respectively, in the Ap horizon, suggesting that the soils was mechanically unfavourable to root growth and tillage. In the plow pan, the fertilization treatments had greater TS and PR than in CK. TS and PR of the tested soil aggregates were negatively correlated to SOC content and soil porosity. This study suggested that chemical fertilization could cause deterioration of mechanical properties while application of organic manure could improve soil stability and mechanical properties.

关键词： soil aggregate stability chemical fertilization organic matter penetration resistance tensile strength

NUMERICAL SIMULATION OF SCOURING PROCESS UNDER SPILLWAY

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Journal of Hydrodynamics 2001年第4期13卷 55-59页

作者： Yang Jian-ming, Wu Jian-hua nanjing Hydraulic Research institute, nanjing 210029, China nanjing Hydraulic Res. Inst. Nanjing 210029 China

The scour problem under spillway has received a lot of attention in the past decades. For such a complicated problem, most numerical modeling presented only dealt with the water flows in equilibrium scour pools without considering the changing topography of the riverbed. In this paper, the dynamic process is handled with moving grids, and the governing equations are solved using finite volume method with colocated variable arrangement on boundary-fitted non-orthogonal grids. The results show that the given method is efficient, with which the variation of flow parameters, such as mean velocity and mean pressure, etc., can be computed correctly.

关键词： scour pool numerical simulation space conservation law moving grids

An output delay approach to fault estimation for sampled-data systems

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Science China(Information Sciences) 2012年第9期55卷 2128-2138页

作者： WEN ChengLin 1,QIU AiBing 2 & JIANG Bin 3.1 institute of Information and Control,Hangzhou Dianzi University,Hangzhou 3.0018,China 2 School of Electrical Engineering,Nantong University,Nantong 226019,China 3.College of Automation Engineering,nanjing University of Aeronautics and Astronautics,nanjing 210016,China 1. institute of Information and Control Hangzhou Dianzi University Hangzhou 310018 China2. School of Electrical Engineering Nantong University Nantong 226019 China3. College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

The problem of fault estimation for a class of non-uniformly sampled-data systems is investigated from the time delay point of view in this ***,the output delay approach is employed to model the sampled-data system as a continuous-time one with time-varying delay ***,based on the analysis of the inapplicability of the adaptive fault diagnosis observer in such class of time-delay systems,a novel augmented fault estimation observer design method is proposed to guarantee the exponential convergence of the estimation ***,an extension to the case of time varying fault estimation for the noisy sampled-data systems is ***,simulation results of a flight control system are presented to demonstrate the effectiveness of the proposed method.

关键词： fault estimation non-uniformly sampled-data augmented observer output delay

Pollen records of Holocene vegetation and climate changes in the Longzhong Basin of the Chinese Loess Plateau

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Progress in Natural Science:Materials International 2007年第12期17卷 1445-1456页

作者： Tang Lingyu1 and An Chengbang2(1. nanjing institute of Geology and Paleontology, Chinese Academy of Sciences, nanjing 210008, China 2. Key Laboratory of Western China’s Environment Systems, MOE, Lanzhou University, Lanzhou 73.000, China) nanjing institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China Key Laboratory of Western China’s Environment Systems MOE Lanzhou University Lanzhou 730000 China

Pollen records with an average time resolution of 20-200 years from Holocene loess sections at Dingxi, Qin'an, and other localities of Gansu Province reveal a detailed history of vegetation and climate changes in the western Loess Plateau. For most time of the Holocene, the landscape was dominated by grasslands or forest steppes. However, during the middle Holocene (7.5-5.8 ka BP), relatively dense forests developed, and the endemic vegetation flourished, suggesting a much warmer and more humid climate condition than the present. Superimposed upon this general pattern are several dry intervals marked by the episodic expansion of grasslands or forest steppe. Xeric vegetation expanded after 3.8 ka BP, indicating a trend towards dry conditions.

关键词： pollen records glasslands coniferous forests Holocene Loess Plateau.

One-step estimation for varying coefficient models

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Science China Mathematics 2005年第2期48卷 198-213页

作者： TANG Qingguo & WANG Jinde Department of Mathematics, nanjing University, nanjing 210093. China institute of Sciences, PLA University of Science and Technology, nanjing 210007, China 1. Department of Mathematics Nanjing University 210093 Nanjing China 2. institute of Sciences PLA University of Science and Technology 210007 Nanjing China

A one-step method is proposed to estimate the unknown functions in the varying coefficient models, in which the unknown functions admit different degrees of smoothness. In this method polynomials of different orders are used to approximate unknown functions with different degrees of smoothness. As only one minimization operation is employed, the required computation burden is much less than that required by the existing two-step estimation method. It is shown that the one-step estimators also achieve the optimal convergence rate. Moreover this property is obtained under conditions milder than that imposed in the two-step estimation method. More importantly, as only one minimization operation is employed, the full asymptotic properties, not only the asymptotic bias and variance, but also the asymptotic distributions of the estimators can be derived. The asymptotic distribution results will play a key role for making statistical inference.

关键词： varying coefficient model, one-step estimation, asymptotic distribution, optimal convergence rate.

Covarying modes of the Pacific SST and northern hemispheric midlatitude atmospheric circulation anomalies during winter

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Progress in Natural Science:Materials International 2008年第10期18卷 1261-1270页

作者： Yimin Zhu~(a,b,*) Xiuqun Yang~a Qian Xie~b Yongqiang Yu~c ~a Department of A tmospheric Science,nanjing University,nanjing 210093.China ~b institute of {3.,PLA University of Science and Technology,nanjing 211101,China ~c LASG,institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China Department of Atmospheric Science Nanjing University Nanjing 210093 China institute of meteorology PLA University of Science and Technology Nanjing 211101 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The interannual-to-interdecadal relationship between the Pacific sea surface temperature (SST) and the northern hemispheric midlati- tude’s atmosphere represented by the circumpolar vortex was documented with the global oceanic and atmospheric reanalysis data of recent 50 *** covarying modes of the Pacific SST and northern circumpolar vortex anomalies during winter were examined using the sin- gular value decomposition and wavelet analysis *** is the interannual,ENSO-related mode and the other is the interdecadal, North Pacific SST-related mode with a period of around 20 *** two modes exhibit distinct spatial *** the interannual mode,the SST anomaly is characterized by a typical ENSO pattern with the principal signature in the tropical eastern Pacific and secondary one in the central North Pacific,while the atmospheric anomaly is regional,characterized by a Pacific-North American *** the inter- decadal mode,large SST anomaly is located in the central North Pacific,while the atmospheric anomaly is zonally global,associated with the midlatitute’s standing long-wave *** the central North Pacific is colder,the long-wave is stronger,and vice *** investigations suggest that the interdecadal mode could involve an interaction between "two oceans and an atmosphere".

关键词： Sea surface temperature Atmospheric circulation ENSO Decadal variability

Experimental Study on Superficial Sliding of a New Type of Offshore Platform

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China Ocean Engineering 1996年第1期11卷 121-128页

作者： Wang Zhaojing Zhang Ling Senior Engineer, Geotechnical Engineering Department, nanjing Hydraulic Research institute, nanjing 210024 Engineer, Geotechnical Engineering Department, nanjing Hydraulic Research institute, nanjing 210024 Geotechnical Engineering Department Nanjing Hydraulic Research Institute Nanjing 210024

In order to verify the theoretical design and computation of a new type of platform, laboratory model test of the superficial sliding of the platform is carried out. Test results show that the requirement for the stability of the platform can be satisfied, and the API-82 criterion can be met. It is also suggested that, in order to enhance the stability of the platform, a buried- pad with porous holes and a long apron-board should be adopted in the design of the new type of platform.

关键词： superficial sliding model test offshore platform