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Microhabitat Effect on Iron Distribution and Transfer in Carex pseudocuraica in Sanjiang Plain Wetlands

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Chinese Geographical Science 2010年第4期20卷 363-371页

作者： zou Yuanchun LU Xianguo jiang ming YU Xiaofei Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China

Ten clonal units of Carex pseudocuraica growing in four different microhabitats (perennial flooded ditch water,perennial flooded ditch sediment,seasonal flooded ditch sediment and perennial flooded soil) of the Sanjiang Plain,Northeast China,were collected randomly for phenotypic plasticity *** content,chemical and physical properties of substrates and the total Fe of nine plant modules were measured as *** results show that the performance of the *** is affected by the microhabitat,with the greatest performance score in perennial flooded ditch water,and the lowest in perennial flooded *** biomass allocation indexes indicate that much more mass is allocated to stems and roots to expand colonization *** distribution of the total Fe in plant modules appears as pyramids from the tip to the root,while marked differences are observed in the distribution proportion of stems,tillering nodes and roots that are allometrically *** transfer from substrates to the plant is mainly controlled by the substrate *** differences of iron distribution and transfer in the plant in different microhabitats are attributed to the iron contents of the substrates as well as the phenotypic plasticity of the plant.

关键词： iron distribution iron transfer Carexpseudocuraica Sanjiang Plain

Multi-objectives nonlinear structure optimization for actuator in trajectory correction fuze subject to high impact loadings

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Defence Technology（防务技术） 2021年第4期17卷 1338-1351页

作者： jiang-hai Hui Min Gao ming Li ming-rui Li Hui-hui zou Gang Zhou Northwest Institute of Nuclear Technology Xi’an710025China shijiazhuang Campus Army Engineering UniversityShijiazhuang050003China

This paper presents an actuator used for the trajectory correction fuze,which is subject to high impact loadings during launch.A simulation method is carried out to obtain the peak-peak stress value of each component,from which the ball bearings are possible failures according to the ***,three schemes against impact loadings,full-element deep groove ball bearing and integrated raceway,needle roller thrust bearing assembly,and gaskets are utilized for redesigning the actuator to effectively reduce the bearings’***,multi-objectives optimization still needs to be conducted for the gaskets to decrease the stress value further to the yield *** gasket’s structure parameters and three bearings’peak-peak stress are served as the four optimization variables and three objectives,*** Latin hypercube design is used for generating sample points,and Kriging model selected according to estimation result can establish the relationship between the variables and objectives,representing the simulation which is ***,two optimization algorithms work out the Pareto solutions,from which the best solutions are selected,and verified by the simulation to determine the gaskets optimized structure *** can be concluded that the simulation and optimization method based on these components is effective and efficient.

关键词： Actuator Trajectory correction fuze Impact loadings Optimized Latin hypercube design Kriging model Optimization algorithm

Bibliometrics-based Research Hotspots and Development Trends in Eco-hydrology of Dammed Rivers

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Chinese Geographical Science 2023年第6期33卷 1153-1164页

作者： CHEN Yingyi FENG mingming shi Guoqiang jiang Mengyu jiang ming Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun130102China University of Chinese Academy of Sciences Beijing100049China Changbai Mountain Academy of Science Antu133613JilinChina Jilin Provincial Joint Key Laboratory of Changbai Mountain Biocoenosie and Biodiversity Antu133613JilinChina Changbai Mountain Biodiversity Conservation National Long-term Scientific Research Base Antu133613JilinChina College of Geographical Sciences Changchun Normal UniversityChangchun130102China

Water conservation initiatives satisfy the demand for water supply,electricity generation,irrigation,and flood *** helping humanity,they have also altered the ecosystem of natural rivers,impacted river ecology,disrupted river continuity,and jeopardized the existence of aquatic creatures in *** the impacts of dam construction on rivers can enhance our knowledge of river ecological and environmental concerns and help sustain the health of river ecosystems,thereby realizing the harmony between humans and water in both theoretical and practical *** study used bibliometrics and constructed an author-keyword 2-mode matrix network using Co-Occurrence software to identify the hotspots and research trend in eco-hydrology of dammed *** identified‘FLOW’‘SEDIMENT’‘QUALITY’and‘MODEL’as the research hotspots in the ecological impact of dammed rivers,and combined the related literatures,we highlight the research progress in the four *** the research shortcomings and prospect were discussed,including strengthening the monitoring and analysis of critical ecological variables,enhancing the hydrological monitoring density for small rivers,strengthening the research of relationship between eutrophication and zooplankton,establishing multiscale approaches,and combining multi-sources information technologies to improve parameter accuracy in the model research.

关键词： dammed river eco-hydrology bibliometrics ecological impact Co-Occurrence software

Joint salient object detection and existence prediction

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Frontiers of Computer Science 2019年第4期13卷 778-788页

作者： Huaizu jiang ming-ming CHENG shi-Jie LI Ali BORJI Jingdong WANG College of Information and Computer Sciences University of Massachusetts Amherst Amherst MA 01003 USA CCCE Nankai University Jinnan Campus Tianjin 300353 China Center for Research in Computer Vision University of Central Florida Orlando FL 32816 USA Microsoft Research Beijing 100080 China

Recent advances in supervised salient object detection modeling has resulted in significant performance improvements on benchmark datasets. However, most of the existing salient object detection models assume that at least one salient object exists in the input image. Such an assumption often leads to less appealing saliency maps on the background images with no salient object at all. Therefore, handling those cases can reduce the false positive rate of a model. In this paper, we propose a supervised learning approach for jointly addressing the salient object detection and existence prediction problems. Given a set of background-only images and images with salient objects, as well as their salient object annotations, we adopt the structural SVM framework and formulate the two problems jointly in a single integrated objective function: saliency labels of superpixels are involved in a classification term conditioned on the salient object existence variable, which in turn depends on both global image and regional saliency features and saliency labels assignments. The loss function also considers both image-level and regionlevel mis-classifications. Extensive evaluation on benchmark datasets validate the effectiveness of our proposed joint approach compared to the baseline and state-of-the-art models.

关键词： salient object detection existence prediction joint inference saliency detection

Transfer and Transformation of Soil Iron and Implications for Hydrogeomorpholocial Changes in Naoli River Catchment, Sanjiang Plain, Northeast China

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Chinese Geographical Science 2011年第2期21卷 149-158页

作者： jiang ming LU Xianguo WANG Hongqing zou Yuanchun WU Haitao Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China National Wetland Research Center USGS Lafayette Louisiana 70506 USA

Wetland soils are characterized by alternating redox process due to the fluctuation of waterlogged conditions. Iron is an important redox substance, and its transfer and transformation in the wetland ecosystem could be an effective indicator for the environment changes. In this paper, we selected the Naoli River catchment in the Sanjiang Plain, Northeast China as the study area to analyze the dynamics of transfer and transformation of soil iron, and the relationship between iron content change and environmental factors. The results show that the total and crystalline iron contents reach the peak in the depth of 60 cm in soil profile, while the amorphous iron content is higher in the topsoil. In the upper reaches, from the low to high landscape positions, the total and crystalline iron contents decrease from 62.98 g/kg to 41.61 g/kg, 22.82 g/kg to 10.53 g/kg respectively, while the amorphous iron content increases from 2.42 g/kg to 8.88 g/kg. Amorphous iron content has positive correlation with organic matter and soil water contents, while negative correlation with pH. Moreover, both the crystalline and amorphous iron contents present no correlation with total iron content, indicating that environmental factors play a more important role in the transfer and transformation of iron other than the content of the total iron. Different redoximorphic features were found along the soil profile due to the transfer and transformation of iron. E and B horizons of wetland soil in the study area have a matrix Chroma 2 or less, and all the soil types can meet the criteria of American hydric soil indicators except albic soil.

关键词： wetland soil landscape position hydrogeomorpholocial condition redoximorphic feature iron

Entanglement Dynamics of Arbitrary Two-Qubit Pure States under Amplitude and Phase Damping Channels

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Chinese Physics Letters 2011年第2期28卷 51-54页

作者： jiang Feng-Jian shi ming-Jun DU jiang-Feng Department of Modern Physics University of Science and Technology of China and Hefei National Laboratory for Physical Sciences at MicroscaleHefei 230026

Analytic results are presented for the entanglement evolution for arbitrary two-qubit pure state under amplitude damping and particularly phase damping *** disentanglement time and the relationship between it and the form of initial state are given *** lower bounds of disentanglement time are obtained and shown to be the monotone functions of initial concurrence.

关键词： monotone bounds arbitrary

S4Net: Single stage salient-instance segmentation

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Computational Visual Media 2020年第2期6卷 191-204页

作者： Ruochen Fan ming-ming Cheng Qibin Hou Tai-jiang Mu Jingdong Wang shi-Min Hu BNRist Tsinghua UniversityBeijing100086China Nankai University Tianjin300071China MSRA Beijing100086China

In this paper, we consider salient instance segmentation. As well as producing bounding boxes,our network also outputs high-quality instance-level segments as initial selections to indicate the regions of interest. Taking into account the category-independent property of each target, we design a single stage salient instance segmentation framework, with a novel segmentation branch. Our new branch regards not only local context inside each detection window but also the surrounding context, enabling us to distinguish instances in the same scope even with partial *** network is end-to-end trainable and is fast(running at 40 fps for images with resolution 320 × 320). We evaluate our approach on a publicly available benchmark and show that it outperforms alternative solutions. We also provide a thorough analysis of our design choices to help readers better understand the function of each part of our network. Source code can be found at https://***/Ruochen Fan/S4 Net.

关键词： salient-instance segmentation salient object detection single stage region-of-interest masking

Large Deviation Principle for the Fourth-order Stochastic Heat Equations with Fractional Noises

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Acta Mathematica Sinica,English Series 2010年第1期26卷 89-106页

作者： Yi ming jiang Ke Hua shi Yong Jin WANG School of Mathematical Sciences and LPMC Nankai University Tianjin 300071 P. R. China

In this paper, we shall study a fourth-order stochastic heat equation driven by a fractional noise, which is fractional in time and white in space. We will discuss the existence and uniqueness of the solution to the equation. Furthermore, the regularity of the solution will be obtained. On the other hand, the large deviation principle for the equation with a small perturbation will be established through developing a classical method.

关键词： fourth-order stochastic heat equation fractional noise existence and uniqueness regularity large deviation principle

Voidage correction method for DEM study of 3D pebble flows in a bed of cycloidal base

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Particuology 2024年第10期93卷 30-40页

作者： Zirui Xia minglei shi Quan zou Nan Gui Xingtuan Yang Jiyuan Tu Shengyao jiang Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy TechnologyKey Laboratory of Advanced Reactor Engineering and SafetyMinistry of EducationTsinghua UniversityBeijing100084China Department of Engineering Physics Tsinghua UniversityBeijing100084China Department of Automation Tsinghua UniversityBeijing100084China School of Engineering RMIT UniversityMelbourneVIC3083Australia

Voidage(porosity or void fraction)in packed particles(or pebbles)is of fundamental importance in calculating the pressure drop,obtaining the drag,predicting the bed permeability,estimating the neutron streaming,*** the case when particles are deformed,a method of voidage correction during the packing state is proposed using a Discrete Element Method(DEM)simulation of 3D pebble flow inside a bed of cycloidal base.A function to evaluate the remaining volume of a pebble intercepted by horizontal and vertical planes is proposed for voidage *** that,the process of solving voidage distribution is provided in *** this method,the voidage inside the cycloidal-base pebble bed is obtained to refer to reported similar data for *** method can be potentially used for dynamical voidage calculation in CFD-DEM simulation which can get suitable voidage distribution after the correction.

关键词： Voidage Pebbleflow Packed bed Discreteelementmethod Cycloidal base KD-Tree Volume correction