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Journal of Landscape Research 2020年第4期12卷 53-57页

作者： ZHANG Lvshui yin Zhongjian CHEN Chen hu huixia LIU Hao College of Landscape Architecture and Arts Jiangxi Agricultural UniversityNanchangJiangxi 330045China

Urban park is one of the few green spaces that retain natural traces and are easy for the elderly to reach,and it has become the main place for the elderly to carry out leisure,entertainment,physical fi tness and interpersonal *** reasonable layout of urban parks is of great signifi cance to improve the quality of life of the elderly in old *** this article,using the network analysis method in ArcGIS software,the accessibility of urban parks in Xihu District of Nanchang City based on elderly walking was evaluated and analyzed,and three strategies for optimizing the layout of the urban parks were proposed,including increasing the number of urban parks,improving the urban traffic network,and strengthening urban greenway planning and *** research results can provide reference for the optimal layout of urban parks in Xihu District,Nanchang City,so that the urban parks can better meet the outdoor leisure needs of the elderly,and the elderly’s sense of well-being and gain is enhanced.

关键词： The elderly Accessibility Urban park Layout optimization ArcGIS

Evaluating students' learning situations using “Four-quadrant law”

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计算机教育 2018年第12期 28-35页

作者： Jinze Liu Dongyang hu Xunhui Zhang Tao Wang Yue Yu Gang yin College of Computer National University of Defense Technology

Evaluation is widely acknowledged as a powerful means of improving the quality of education and it is a very important component of the education system. However, the current mainstream evaluation method is based on the examination as the common way, which has very limited help to instructors' teaching. In this paper, based on an online learning platform named "educoder", we design an evaluation method by using "Four-quadrant law", which divides students' learning situations into four types. In addition, we provide some suggestions for instructors about how to give targeted teaching to different students in each type. We verify that our method is useful by setting up experiments. The experiment results show that our method can effectively improve the quality of instructors' teaching.

关键词： evaluation four-quadrant law classification

Hologenomic insights into mammalian adaptations to myrmecophagy

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National Science Review 2023年第4期10卷 24-36页

作者： Shao-Chen Cheng Chun-Bing Liu Xue-Qin Yao Jing-Yang hu Ting-Ting yin Burton K.Lim Wu Chen Guo-Dong Wang Cheng-Lin Zhang David M.Irwin Zhi-Gang Zhang Ya-Ping Zhang Li Yu State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan School of Life SciencesYunnan University State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of Sciences Department of Natural History Royal Ontario Museum Guangzhou Zoo Center for Excellence in Animal Evolution and Genetics Kunming Institute of ZoologyChinese Academy of Sciences Beijing Zoo Department of Laboratory Medicine and Pathobiology University of Toronto

Highly specialized myrmecophagy(ant-and termite-eating) has independently evolved multiple times in species of various mammalian orders and represents a textbook example of phenotypic evolutionary convergence. We explored the mechanisms involved in this unique dietary adaptation and convergence through multi-omic analyses, including analyses of host genomes and transcriptomes, as well as gut metagenomes, in combination with validating assays of key enzymes’ activities, in the species of three mammalian orders(anteaters, echidnas and pangolins of the orders Xenarthra, Monotremata and Pholidota, respectively) and their relatives. We demonstrate the complex and diverse interactions between hosts and their symbiotic microbiota that have provided adaptive solutions for nutritional and detoxification challenges associated with high levels of protein and lipid metabolisms, trehalose degradation, and toxic substance detoxification. Interestingly, we also reveal their spatially complementary cooperation involved in degradation of ants’ and termites’ chitin exoskeletons. This study contributes new insights into the dietary evolution of mammals and the mechanisms involved in the coordination of physiological functions by animal hosts and their gut commensals.

关键词： myrmecophagy adaptive evolution hologenome genomics metagenomics convergent evolution

A NEW DAMAGE MECHANICS BASED APPROACH TO FATIGUE LIFE PREDICTION AND ITS ENGINEERING APPLICATION

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Acta Mechanica Solida Sinica 2015年第5期28卷 510-520页

作者： Fei Shen Weiping hu Qingchun Meng Miao Zhang Institute of Solid Mechanics School of Aeronautics Science and Engineering Beihang University Institute of Manned Space System Engineering China Academy of Space Technology

An approach based on continuum damage mechanics to fatigue life prediction for structures is proposed. A new fatigue damage evolution equation is developed, in which the pa- rameters are obtained in a simple way with reference to the experimental results of fatigue tests on standard specimens. With the utilization of APDL language on the ANSYS platform, a finite element implementation is presented to perform coupling operation on damage evolution of mate- rial and stress redistribution. The fatigue lives of some notched specimens and a Pitch-change-link are predicted by using the above approach. The calculated results are validated with experimental data.

关键词： fatigue damage model damage mechanics fatigue life finite element method

Time-Dependent Demographic Prediction Based on Time-Back-Propagation Method

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Chinese Journal of Electronics 2018年第1期27卷 35-40页

作者： KE Yuyang XIONG Yan hu Yiqing LIU Shichen School of Computer Science University of Science and Technology of China Department of Computer Science Hefei University

In various applications like personalized search and recommendation, full demographic information is a precondition for many applications’ well performance,but such ideal dataset rarely exists in practical ***’s worse, absence of key characteristics(e.g., baby’s age in maternal and infant commodity recommendation)makes these applications struggle. We design a novel solution to solve the problem of time-dependent demographic prediction. The key insight behind our approach is, we leverage a Time-back-propagation(TBP) method to take the internal time correlation of historical behaviours into consideration and collect all available data to train a classifier, which is a mapping from user’s historical behaviours to the demographic information. We demonstrate the effectiveness of our method through experiments of baby’s age prediction. Our algorithm performs more balanced on each age group, and can predict Baby’s age(BA) accurately in 78.2% on a real-world dataset with 2,058,909 items of a ma jor E-commerce site.

关键词： Time-back-propagation(TBP) Time series Time-dependent demographic prediction

Classification of rice seed variety using point cloud data combined with deep learning

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International Journal of Agricultural and Biological Engineering 2021年第2期14卷 206-212页

作者： Yan Qian Qianjin Xu yingying Yang hu Lu hua Li Xuebin Feng Wenqing yin College of Artificial Intelligence Nanjing Agriculture UniversityNanjing 210031China College of Engineering Nanjing Agriculture UniversityNanjing 210031China

Rice variety selection and quality inspection are key links in rice *** with two-dimensional images,three-dimensional information on rice seeds shows the appearance characteristics of rice seeds more comprehensively and *** study proposed a rice variety classification method using three-dimensional point cloud data of the surface of rice seeds combined with a deep learning network to achieve the rapid and accurate identification of rice ***,a point cloud collection platform was set up with a Raytrix light field camera as the core to collect three-dimensional point cloud data on the surface of rice seeds;then,the collected point cloud was filled,filtered and smoothed;after that,the point cloud segmentation is based on the RANSAC algorithm,and the point cloud downsampling is based on a combination of random sampling algorithm and voxel grid filtering ***,the processed point cloud was input to the improved PointNet network for feature extraction and species *** improved PointNet network added a cross-level feature connection structure,made full use of features at different levels,and better extracted the surface structure features of rice *** testing,the improved PointNet model had an average classification accuracy of 89.4%for eight varieties of rice,which was 1.2%higher than that of the PointNet *** method proposed in this study combined deep learning and point cloud data to achieve the efficient classification of rice varieties.

关键词： rice seed variety classification point cloud data deep learning light field camera

FORMATION LAW OF PHASES IN ULTRAFINE POWDERS OF Al-Cu ALLOY PREPARED BY GAS EVAPORATION PROCESS

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中国有色金属学会会刊：英文版 1999年第2期9卷 128-133页

作者： Yan, Hongge Chen, Zhenhua hu, Xiang huang, Peiyun Central South Univ of Technology Changsha China

１ＩＮＴＲＯＤＵＣＴＩＯＮＵｌｔｒａｆｉｎｅｐｏｗｄｅｒｓｗｉｔｈａｐａｒｔｉｃｌｅｓｉｚｅｌｅｓｔｈａｎ１００ｎｍｈａｖｅｅｘｃｅｌｅｎｔｐｒｏｐｅｒｔｉｅｓｉｎｃｏｎｔｒａｓｔｔｏｃｏａｒｓｅｇｒａｉｎｍａｔｅｒ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＵｌｔｒａｆｉｎｅｐｏｗｄｅｒｓｗｉｔｈａｐａｒｔｉｃｌｅｓｉｚｅｌｅｓｔｈａｎ１００ｎｍｈａｖｅｅｘｃｅｌｅｎｔｐｒｏｐｅｒｔｉｅｓｉｎｃｏｎｔｒａｓｔｔｏｃｏａｒｓｅｇｒａｉｎｍａｔｅｒｉａｌｓ［１，２］ａｎｄｈａｖｅｗ...

关键词： gas evaporationvapor condensationultrafine powdersalloy powder

Application of a green coagulant with PACl in efficient purification of turbid water and its mechanism study

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Journal of Environmental Sciences 2019年第7期31卷 168-180页

作者： Yuxiang Xue Zhouzhou Liu Aimin Li hu Yang State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University

The applications of natural polymeric flocculants due to their green feature has been recently received much more attention. In this work, the combined usages of a cationic starch-based coagulant and polyaluminum chloride(PACl) were extensively evaluated for various addition sequences in the coagulation of both raw(surface water from the Jiuxiang River) and synthetic turbid water(two kaolin suspensions with different initial turbidities).Two typical cationic starch-based coagulants with different structures(St-G and St-E) were tried. In comparison to St-G, St-E and PACl used individually as well as St-G and St-E dosed after PACl, the combination of the starch-based coagulants fed before PACl showed higher turbidity removal efficiency, which featured not only less optimal doses of both inorganic and organic coagulants but also lower residual turbidity. On the basis of a detailed analysis of the particle size and its distribution in solution supernatants before and after coagulation by two starch-based coagulants and PACl, polymeric coagulants preferentially coagulate the small-sized colloids due to their distinct long-chain structures, but PACl preferentially coagulates the medium-sized ones. Thus, the medium-sized particles that were previously formed by the starch-based coagulants would be collectively and effectively removed by the subsequent addition of PACl. The addition sequence of the inorganic and organic coagulants in their combined usage is an important factor for improvement of the turbidity removal efficiency in practice.

关键词： Cationic starch-based green coagulants Polyaluminum chloride Combined coagulation Synergistic coagulation effects Synergistic mechanisms

Arsenic uptake, accumulation and phytofiltration by duckweed (Spirodela polyrhiza L.)

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Journal of Environmental Sciences 2011年第4期23卷 601-606页

作者： Xin Zhang ying hu Yunxia Liu Baodong Chen State key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

This study investigates arsenic （As） accumulation and tolerance of duckweed Spirodela polyrhiza L. and its potential for As phytofiltration. S. polyrhiza was able to survive in high concentration of As（V） solution. The EC 50 values （± SE） based on the external As（V） were （181.66 ± 20.12） μmol/L. It accumulated （999 ± 95） mg As/kg dw when exposed in 320 μmol/L As（V） solution for one week, and was able to take up appropriately 400 mg As/kg dw in tissues without a significant biomass loss. The EC 50 values （the effective concentration of As（V） in the nutrient solution that caused a 50% inhibition on biomass production） was （866 ± 68） mg/kg dw for the tissues, indicating that S. polyrhiza had a high capability of As accumulation and tolerance. The uptake kinetic parameters V max was （55.33 ± 2.24） nmol/（g dw·min） and K m was （0.144 ± 0.011） mmol/L. Within 72 hr, S. polyrhiza decreased As concentration in the solution from 190 to 113 ng/mL with a removal rate of 41%. The study suggested that this floating aquatic plant has some potential for As phytofiltration in contaminated water bodies or paddy soils.

关键词： arsenic duckweed phytofiltration Spirodela polyrhiza L.

High-precision RCS measurement of aircraft's weak scattering source

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Chinese Journal of Aeronautics 2016年第3期29卷 772-778页

作者： hu Chufeng Li Nanjing Chen Weijun Zhang Linxi Science and Technology on UAV Laboratory Northwestern Polytechnical University

The radar cross section （RCS） of weak scattering source on the surface of an aircraft is usually less than -40 dBsm. How to accurately measure the RCS characteristics of weak scattering source is a technical challenge for the aircraft＇s RCS measurement. This paper proposes separating and extracting the two-dimensional （2D） reflectivity distribution of the weak scattering source with the microwave imaging algorithm and spectral transform so as to enhance its measurement preci- sion. Firstly, we performed the 2D microwave imaging of the target and then used the 2D gating function to separate and extract the reflectivity distribution of the weak scattering source. Secondly, we carried out the spectral transform of the reflectivity distribution and eventually obtained the RCS of the weak scattering source through calibration. The prototype experimental results and their analysis show that the measurement method is effective. The experiments on an aircraft＇s low-scattering conformal antenna verify that the measurement method can eliminate the clutter on the surface of aircraft. The precision of measuring a -40 dBsm target is 3 5 dB better than the existing RCS measurement methods. The measurement method can more accurately obtain the weak scattering source＇s RCS characteristics.

关键词： Microwave imaging RCS measurement Reftectivity distributionSpectral transform Weak scattering source