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| 1 | Spatiotemporal characteristics, patterns, and causes of land-use changes in China since the late 1980s显示文摘Land-use/land-cover 变化(LUCC ) 有连接到人和自然相互作用。瓷器 Land-Use/cover 数据集(CLUD ) 从 1980 年代末在 5 年的间隔定期被更新到 2010,与基于 Landsat TMETM+ 图象的标准过程。陆地使用动态区域化方法被建议分析主要陆地使用变换。在国家规模的陆地使用变化的空间与时间的特征,差别,和原因然后被检验。主要调查结果如下被总结。越过中国的陆地使用变化(LUC ) 在最后 20 年(19902010 ) 里在空间、时间的特征显示了一个重要变化。农田变化的区域在南方减少了并且在北方,而是仍然是的全部的区域增加了几乎未改变。回收农田从东北被转移到西北。布满建筑物陆地很快膨胀了,主要在东方被散布,并且逐渐地展开到中央、西方的中国。树林首先减少了,然后增加但是荒芜的区域是反面。草地继续减少。在中国的 LUC 的不同空间模式被发现在之间迟了第 20 世纪并且早第 21 世纪。原版 13 个 LUC 地区在一些地区被边界的变化由 15 个单位代替。包括的这些变化(1 ) 的主要空间特征加速的扩大布满建筑物在 Huang-Huai-Hai 区域,东南的沿海的区域,长江的中流区域,和四川盆登陆;(2 ) 从东北中国和东方内部蒙古在北方转移了陆地开垦到绿洲在西北中国的农业区域;(3 ) 从在到稻的东北中国的喂雨的农田的连续转变回答;并且(4 ) 为在内部蒙古,黄土高原,和西南的多山的区域的南部的农业牧剧的交错群落的格林工程的谷物的有效性。在最后二十年,尽管在北方的气候变化在农田影响了变化,政策规定和经济驱动力仍然是越过中国的 LUC 的主要原因。在第 21 世纪的第一十年期间,在陆地使用模式驾驶了变化的人为的因素从单程的陆地开发转移了强调到开发和保存。动态区域化方法被用来在单位的 zoning 边界,地区的内部特征,和生长和减少的空间模式分析变化。结果揭示了变化过程的模式,也就是 LUC 的过程和在在不同阶段的特征的地区性的差别。地区的生长和减少在这动态 LUC zoning,在统一边界的变化,和在前者和后者十年之间的变化紧张的特征期间被检验。在为在不同类型和陆地使用的不同区域的变化的陆地使用和原因的模式和过程之间的其他的转变的模式被探索。 | LIU Jiyuan KUANG Wenhui ZHANG Zengxiang XU Xinliang QIN Yuanwei NING Jia ZHOU Wancun ZHANG Shuwen LI Rendong YAN Changzhe WU Shixin SHI Xuezheng JIANG Nan YU Dongsheng PAN Xianzhang CHI Wenfeng | 2014 | Journal of Geographical Sciences2014，24，2： | 245 |
| 2 | Mitochondrial PKM2 regulates oxidative stress-induced apoptosis by stabilizing Bcl2显示文摘 | Ji Liang Ruixiu Cao Xiongjun Wang Yajuan Zhang Pan Wang Hong Gao Chen Li Fan Yang Rong Zeng Ping Wei Dawei Li Wenfeng Li Weiwei Yang | 2017 | Cell Research2017，27，3： | 39 |
| 3 | Review on monolayer CBN superabrasive wheels for grinding metallic materials显示文摘A state-of-the-art review on monolayer electroplated and brazed cubic boron nitride(CBN) superabrasive wheels for grinding metallic materials has been provided in this article. The fabrication techniques and mechanisms of the monolayer CBN wheels are discussed. Grain distribution, wheel dressing, wear behavior, and wheel performance are analyzed in detail. Sample applications of monolayer CBN wheel for grinding steels, titanium alloys, and nickel-based superalloys are also provided. Finally, this article highlights opportunities for further investigation of monolayer CBN grinding wheels. | Ding Wenfeng Barbara Linke Zhu Yejun Li Zheng Fu Yucan Su Honghua Xu Jiuhua | 2017 | Chinese Journal of Aeronautics2017，30，1： | 24 |
| 4 | Agriculture Green Development: a model for China and the world显示文摘Realizing sustainable development has become a global priority.This holds,in particular,for agriculture.Recently,the United Nations launched the Sustainable Development Goals(SDGs),and the Nineteenth National People’s Congress has delivered a national strategy for sustainable development in China—realizing green development.The overall objective of Agriculture Green Development(AGD)is to coordinate'green'with'development'to realize the transformation of current agriculture with high resource consumption and high environmental costs into a green agriculture and countryside with high productivity,high resource use efficiency and low environmental impact.This is a formidable task,requiring joint efforts of government,farmers,industry,educators and researchers.The innovative concept for AGD will focus on reconstructing the whole crop-animal production and food production-consumption system,with the emphasis on high thresholds for environmental standards and food quality as well as enhanced human well-being.This paper addresses the significance,challenges,framework,pathways and potential solutions for realizing AGD in China,and highlights the potential changes that will lead to a more sustainable agriculture in the future.Proposals include interdisciplinary innovations,whole food chain improvement and regional solutions.The implementation of AGD in China will provide important implications for the countries in developmental transition,and contribute to global sustainable development. | Jianbo SHEN Qichao ZHU Xiaoqiang JIAO Hao YING Hongliang WANG Xin WEN Wen XU Tingyu LI Wenfeng CONG Xuejun LIU Yong HOU Zhenling CUI Oene OENEMA William JDAVIES Fusuo ZHANG | 2020 | Frontiers of Agricultural Science and Engineering2020，7，1： | 18 |
| 5 | Cropland redistribution to marginal lands undermines environmental sustainability显示文摘Cropland redistribution to marginal land has been reported worldwide;however,the resulting impacts on environmental sustainability have not been investigated sufficiently.Here we investigated the environmental impacts of cropland redistribution in China.As a result of urbanization-induced loss of high-quality croplands in south China(~8.5 t ha^(-1)),croplands expanded to marginal lands in northeast(~4.5 t ha^(-1)) and northwest China(~2.9 t ha^(-1)) during 1990-2015 to pursue food security.However,the reclamation in these low-yield and ecologically vulnerable zones considerably undermined local environmental sustainability,for example increasing wind erosion(+3.47%),irrigation water consumption(+34.42%),fertilizer use(+20.02%) and decreasing natural habitats(-3.11%).Forecasts show that further reclamation in marginal lands per current policies would exacerbate environmental costs by 2050.The future cropland security risk will be remarkably intensified because of the conflict between food production and environmental sustainability.Our research suggests that globally emerging reclamation of marginal lands should be restricted and crop yield boost should be encouraged for both food security and environmental benefits. | Wenhui Kuang Jiyuan Liu Hanqin Tian Hao Shi Jinwei Dong Changqing Song Xiaoyong Li Guoming Du Yali Hou Dengsheng Lu Wenfeng Chi Tao Pan Shuwen Zhang Rafiq Hamdi Zherui Yin Huimin Yan Changzhen Yan Shixin Wu Rendong Li Jiuchun Yang Yinyin Dou Wenbin Wu Liqiao Liang Bao Xiang Shiqi Yang | 2022 | National Science Review2022，9，1： | 13 |
| 6 | A multicenter,retrospective.epidemiologic survey of the clinical features and management of bone metastatic disease in China显示文摘Background:Bone metastases are common in patients with advanced cancer.Bisphosphonates(BPs) could prevent or delay the development of skeleton-related events(SREs).The present study aimed to identify the clinical features of and treatment strategies for Chinese patients with bone metastases.Methods:Consecutive cancer patients who had bone metastases and received BP treatment were enrolled.A questionnaire was developed to collect the patients' clinical data,as well as information on the diagnosis and management of bone metastases.Physicians' awareness of the guidelines and knowledge of the application of BP were also assessed.Results:A total of 3223 patients with lung cancer(36.5%),breast cancer(30.9%),prostate cancer(8.5%),and gastrointestinal cancer(5.7%) were included in this study.The sites of bone metastases were the thoracic spine(56.0%),lumbar spine(47.1%),ribs(32.6%),and pelvis(23.2%).The SRE frequency was the highest in patients with multiple myeloma(36.6%),followed by those with lung cancer(25.9%),breast cancer(20.2%),prostate cancer(18.2%),and gastrointestinal cancer(17.3%).Irradiation to the bone was the most frequent SRE(58%in lung cancer patients,45%in breast cancer patients,and 48%in prostate cancer patients).Our survey also showed that 45.5%of patients received BP within 3 months after their diagnosis of bone metastases,whereas the remaining 54.5%of patients did not receive BP treatment until at least 3 months after their diagnosis of bone metastases.The SRE frequency in the former group was significantly lower than that in the latter group(4.0%vs.42.3%,P < 0.05).In patients with more than 6 months of continuous BP treatment,the mean time to the first SRE was significantly longer than that in patients with less than 6 months of continuous BP treatment(7.2 vs.3.4 months,P < 0.05).In addition,12.2%of the physicians were not aware of the efficacy of BP in preventing and delaying SRE.Only half(52.3%) of the physicians agreed that the BP treatment should persist for at least 6 months unless it was intolerable.Conclusions:Our study suggested that prompt and persistent BP treatment was associated with a reduced risk of SREs.However,our survey also revealed that the proper application of BP was not as common as expected in China. | Yunpeng Yang Yuxiang Ma Jin Sheng Yan Huang Yuanyuan Zhao Wenfeng Fang Shaodong Hong Ying Tian Cong Xue Li Zhang | 2016 | Chinese Journal of Cancer2016，35，5： | 13 |
| 7 | Deformation mechanism and stability control of roadway along a fault subjected to mining显示文摘It is difficult to maintain the roadway around a fault because of the fractured surroundings,complex stress environment,and large and intense deformation in the mining process.Based on a tailgate of panel S2205 in Tunliu colliery,in Shanxi province,China,we investigated the evolution of stress and displacement of rocks surrounding the roadway during the drivage and mining period using theoretical analysis,numerical simulation and field trial methods.We analyzed the deformation and failure mechanisms of the tailgate near a fault.The deformation of surrounding rock caused by unloading in the drivage period is large and asymmetric,the roadway convergence increases with activation of the fault and secondary fracture develops in the mining period.Therefore,we proposed a specific control technique of the roadway along a fault as follows:(1) High-strength yielding bolt not only supports the shallow rock to loadbearing structures,but also releases primary deformation energy by use of a pressure release device in order to achieve high resistance to the pressure retained;(2) Grouting of near-fault ribside after initial stabilization of the rock deformation is used to reinforce the broken rock,and to improve the integral load-bearing capacity of the roadway.The research results were successfully applied to a field trial. | Yan Shuai Bai Jianbiao Li Wenfeng Chen Jigang Li Lei | 2012 | International Journal of Mining Science and Technology2012，22，4： | 11 |
| 8 | Advances in fabrication of ceramic corundum abrasives based on sol–gel process显示文摘Corundum abrasives with good chemical stability can be fabricated into various free abrasives and bonded abrasive tools that are widely used in the precision machining of various parts.However,these abrasives cannot satisfy the machining requirements of difficult-to-machine materials with high hardness,high strength,and strong wearing resistance.Although superhard abrasives can machine the above-mentioned materials,their dressing and manufacturing costs are high.By contrast,ceramic corundum abrasives fabricated by sol–gel method is a costeffective product between conventional and superhard abrasives.Ceramic corundum abrasives exhibit self-sharpening and high toughness.In this review,the optimization methods of ceramic corundum abrasive properties are introduced from three aspects:precursor synthesis,particle shaping,and sintering.Firstly,the functional mechanism of seeds and additives on the microstructural and mechanical properties of abrasives is analyzed.Specifically,seeds can reduce the phase transition temperature and improve fracture toughness.The grain size and uniformly dense structure can be controlled by applying an appropriate amount of multicomponent additives.Then,the urgent need of engineering application and machinability of special shape ceramic corundum abrasives is reviewed,and three methods of abrasive shaping are summarized.The micromold replication technique is highly advanced and can be used to prepare functional abrasives.Additionally,the influence of a new sintering method,namely,two-step sintering technique,on the microstructural and mechanical performance of ceramic corundum abrasives is summarized.Finally,the challenge and developmental trend of the optimization of ceramic corundum abrasives are prospected. | Baoteng HUANG Changhe LI Yanbin ZHANG Wenfeng DING Min YANG Yuying YANG Han ZHAI Xuefeng XU Dazhong WANG Sujan DEBNATH Muhammad JAMIL Hao Nan Li Hafiz Muhammad ALI Munish Kumar GUPTA Zafar SAID | 2021 | Chinese Journal of Aeronautics2021，34，6： | 11 |
| 9 | Comparative investigation on high-speed grinding of TiCp/Ti–6Al–4V particulate reinforced titanium matrix composites with single-layer electroplated and brazed CBN wheels显示文摘In order to develop the high-efficiency and precision machining technique of Ti Cp/Ti–6Al–4V particulate reinforced titanium matrix composites(PTMCs), high-speed grinding experiments were conducted using the single-layer electroplated cubic boron nitride(CBN) wheel and brazed CBN wheel, respectively. The comparative grinding performance was studied in terms of grinding force, grinding temperature, grinding-induced surface features and defects. The results display that the grinding forces and grinding temperature obtained with the brazed CBN wheel are always lower than those with the electroplated CBN wheel. Though the voids and microcracks are the dominant grinding-induced surface defects, the brazed CBN wheel produces less surface defects compared to the electroplated wheel according to the statistical analysis results. The maximum materials removal rate with the brazed CBN wheel is much higher than that with the electroplated one. All above indicate that the single-layer brazed CBN super-abrasive wheel is more suitable for high-speed grinding of PTMCs than the electroplated counterpart. | Li Zheng Ding Wenfeng Shen Long Xi Xinxin Fu Yucan | 2016 | Chinese Journal of Aeronautics2016，29，5： | 11 |
| 10 | Analysis of Low Frequency Oscillation and Source Location in Power Systems显示文摘The major problem in current online diagnosis and analysis for power system oscillation is mainly concerned with finding the oscillation source in a fast and correct way using the data collected by the Wide Area Measurement System(WAMS).This paper for the first time proposes a scheme of cut set energy based on WAMS.Independent of accurate parameters,the scheme can make full use of WAMS data based on cut set energy construction and fast calculation to locate the source during oscillation.Afterwards,a scheme of torque decomposition is proposed,based on which the controller’s torque can be divided into damping torque and synchronous torque by calculation through WAMS data,and this paper puts forward the abnormal response and simulation models calibration of influential controllers.Analysis of an oscillation case shows how the cut set energy scheme and the torque decomposition scheme are applied in a real-world power system,and the schemes are proven to be reliable and practical in identifying and locating oscillation sources. | Yinbiao Shu Xiaoxin Zhou Wenfeng Li | 2018 | CSEE Journal of Power and Energy Systems2018，4，1： | 11 |
| 11 | Resistance reduction by bionic coupling of the earthworm lubrication function显示文摘Based on the biological coupling theory, the resistance reduction characteristic of the surface morphology and surface wettability of the earthworm were studied in this paper. The parameters of surface dorsal pore and corrugation were extracted. According to these parameters, the lubrication mechanism of the earthworm surface was analyzed. The distribution of the pores and surface morphology were designed and the bionic coupling samples were prepared. The positive pressure, lubricant flow rate and advancing velocity were selected as the experiment factors while the soil friction resistance as observed object. According to the obtained data of bionic coupling samples from the testing system of biologic signal for tiny soil adhesion test, the optimal samples from the bionic coupling resistance reduction tests were selected through the range analysis. Compared to the normal ones, the soil resistance of bionic coupling samples was reduced by 76.8%. This is of great significance and offers bright prospects for reducing energy loss in terrain mechanics. | LI JianQiao*, KOU BingXue, LIU GuoMin, FAN WenFeng & LIU LinLin Key Laboratory of Bionic Engineering (Jilin University), Ministry of Education of China, Changchun 130022, China | 2010 | Science China(Technological Sciences)2010，53，11： | 10 |
| 12 | The Ghd7 transcription factor represses ARE1 expression to enhance nitrogen utilization and grain yield in rice显示文摘The genetic improvement of nitrogen use efficiency(NUE)of crops is vital for grain productivity and sustainable agriculture.However,the regulatory mechanism of NUE remains largely elusive.Here,we report that the rice Grain number,plant height,and heading date7(Ghd7)gene genetically acts upstream of ABC1 REPRESSOR1(ARE1),a negative regulator of NUE,to positively regulate nitrogen utilization.As a transcriptional repressor,Ghd7 directly binds to two Evening Element-like motifs in the promoter and intron 1 of ARE1,likely in a cooperative manner,to repress its expression.Ghd7 and ARE1 display diurnal expression patterns in an inverse oscillation manner,mirroring a regulatory scheme based on these two loci.Analysis of a panel of 2656 rice varieties suggests that the elite alleles of Ghd7 and ARE1 have undergone diversifying selection during breeding.Moreover,the allelic distribution of Ghd7 and ARE1 is associated with the soil nitrogen deposition rate in East Asia and South Asia.Remarkably,the combination of the Ghd7 and ARE1 elite alleles substantially improves NUE and yield performance under nitrogen-limiting conditions.Collectively,these results define a Ghd7–ARE1-based regulatory mechanism of nitrogen utilization,providing useful targets for genetic improvement of rice NUE. | Qing Wang Qingmei Su Jinqiang Nian Jian Zhang Meng Guo Guojun Dong Jiang Hu Rongsheng Wang Changshuo Wei Guanwen Li Wan Wang Hui-Shan Guo Shaoyang Lin Wenfeng Qian XianzhiXie Qian Qian Fan Chen Jianru Zuo | 2021 | Molecular Plant2021，14，6： | 10 |
| 13 | Prediction on grinding force during grinding powder metallurgy nickel-based superalloy FGH96 with electroplated CBN abrasive wheel显示文摘In this article,a grinding force model,which is on the basis of cutting process of single abrasive grains combined with the method of theoretical derivation and empirical formula by analyzing the formation mechanism of grinding force,was established.Three key factors have been taken into accounts in this model,such as the contact friction force between abrasive grains and materials,the plastic deformation of material in the process of abrasive plowing,and the shear strain effect of material during the process of cutting chips formation.The model was finally validated by the orthogonal grinding experiment of powder metallurgy nickel-based superalloy FGH96 by using the electroplated CBN abrasive wheel.Grinding force values of prediction and experiment were in good consistency.The errors of tangential grinding force and normal grinding force were 9.8%and 13.6%,respectively.The contributions of sliding force,plowing force and chip formation force were also analyzed.In addition,the tangential forces of sliding,plowing and chip formation are 14%,19%and 11%of the normal forces on average,respectively.The pro-posed grinding forcemodel is not only in favor of optimizing the grinding parameters and improving grinding efficiency,but also contributes to study some other grinding subjects(e.g.abrasive wheel wear,grinding heat,residual stress). | Benkai LI Chenwei DAI Wenfeng DING Changyong YANG Changhe LI Olga KULIK Vyacheslav SHUMYACHER | 2021 | Chinese Journal of Aeronautics2021，34，8： | 10 |
| 14 | STUDY ON THE DYNAMIC PROCESS OF RILL EROSION OF LOESS SLOPE SURFACE显示文摘Rill erosion is a dominant process of morphological evolution of the Loess Plateau in China, and deliveries much loess sediment to rivers. Data from two flume experiments conducted on the bare and glass-covered beds indicated that the till flow develops into a series of rolling waves. The shear stress on the rill bed distributes unevenly both spatially and temporally. A new method based on the energy conservation law is proposed in this study. Thus the relationship between the runoff energy consumption from the interaction of water flow and slope bed and soil detachment is formulated. The results showed that the data for the soil detachment rate on slope (Dr) and the energy consumption of runoff (E1) fitted well with newly-developed function. The till erosion occurs when the runoff energy consumption exceeds a critical value. | Zhanbin LI 1.2 Kexin LU2 and Wenfeng DING1 1 The State key Laboratory of Loess Plateau and Dry Land Farming, 712100, Yangling, Shaanxi, P.R.China. 2 Xi’an University of Technology, 710048, Xi’an, Shaanxi, P.R.China. | 2001 | International Journal of Sediment Research2001，16，2： | 9 |
| 15 | Effect of the graphitic degree of carbon supports on the catalytic performance of ammonia synthesis over Ba-Ru-K/HSGC catalyst显示文摘A series of high surface area graphitic carbon materials(HSGCs) were prepared by ball-milling method. Effect of the graphitic degree of HSGCs on the catalytic performance of Ba-Ru-K/HSGC-x(x is the ball-milling time in hour) catalysts was studied using ammonia synthesis as a probe reaction. The graphitic degree and pore structure of HSGC-x supports could be successfully tuned via the variation of ball-milling time. Ru nanoparticles of different Ba-Ru-K/HSGC-x catalysts are homogeneously distributed on the supports with the particle sizes ranging from 1.6 to 2.0 nm. The graphitic degree of the support is closely related to its facile electron transfer capability and so plays an important role in improving the intrinsic catalytic performance of Ba-Ru-K/HSGC-x catalyst. | Wei Jiang Ying Li Wenfeng Han Yaping Zhou Haodong Tang Huazhang Liu | 2014 | Journal of Energy Chemistry2014，23，4： | 8 |
| 16 | Single-cell transcriptome atlas of the leaf and root of rice seedlings显示文摘As a multicellular organism,rice flourishes relying on gene expression diversity among cells of various functions.However,cellular-resolution transcriptome features are yet to be fully recognized,let alone cell-specific transcriptional responses to environmental stimuli.In this study,we apply single-cell RNA sequencing to both shoot and root of rice seedlings growing in Kimura B nutrient solution or exposed to various abiotic stresses and characterize transcriptomes for a total of 237,431 individual cells.We identify 15 and 9 cell types in the leaf and root,respectively,and observe that common transcriptome features are often shared between leaves and roots in the same tissue layer,except for endodermis or epidermis.Abiotic stress stimuli alter gene expression largely in a cell type-specific manner,but for a given cell type,different stresses often trigger transcriptional regulation of roughly the same set of genes.Besides,we detect proportional changes in cell populations in response to abiotic stress and investigate the underlying molecular mechanisms through single-cell reconstruction of the developmental trajectory.Collectively,our study represents a benchmark-setting data resource of single-cell transcriptome atlas for rice seedlings and an illustration of exploiting such resources to drive discoveries in plant biology. | Yu Wang Qing Huan Ke Li Wenfeng Qian | 2021 | Journal of Genetics and Genomics2021，48，10： | 8 |
| 17 | Boolean functions of an odd number of variables with maximum algebraic immunity显示文摘In this paper, we study Boolean functions of an odd number of variables with maximum algebraic immunity. We identify three classes of such functions, and give some necessary conditions of such functions, which help to examine whether a Boolean function of an odd number of variables has the maximum algebraic immunity. Further, some necessary conditions for such functions to have also higher nonlinearity are proposed, and a class of these functions are also obtained. Finally, we present a sufficient and necessary condition for Boolean functions of an odd number of variables to achieve maximum algebraic immunity and to be also 1-resilient. | LI Na QI WenFeng | 2007 | Science in China(Series F)2007，50，3： | 8 |
| 18 | Simultaneous determination of 74 pesticide residues in Panax notoginseng by QuEChERS coupled with gas chromatography tandem mass spectrometry显示文摘This study established a method for the simultaneous determination of 74 pesticide residues in Panax notoginseng by QuEChERS pretreatment method coupled with GC-MS/MS,and carried out pesticide residue analysis on 20 batches of market samples in China.The samples were extracted with acetonitrile,cleaned up with primary secondary amine(PSA)and octadecylsilane(C18)and determined by GC-MS/MS in multiple reaction monitoring(MRM)mode.Matrix-matched calibration was recommended to combat the matrix effect.A good linearity was observed in the range of 10−500 ng/mL with correlation coefficients≥0.9950.The mean recoveries for most of the pesticides were in the range of 70%−120%with RSD<20%.The limits of detection ranged 0.28–2.00μg/kg,while the limits of quantification were 0.94–6.65μg/kg.Following the application of“top-down”approach,the expanded measurement uncertainty for all the analytes was<30%.The proposed method was successfully applied to determine pesticide residues in 20 market samples in China,where 9 pesticides were detected and quintozene exceeded the criteria domestically and abroad. | Huijun Li Jieshan Wu Chao Chen Wenfeng Xin Wensheng Zhang | 2021 | Food Science and Human Wellness2021，10，2： | 8 |
| 19 | Study on Ecological Risk of Land Use in Urbanization Watershed Based on RS and GIS:A Case Study of Songhua River Watershed in Harbin Section显示文摘By using RS and GIS technology,the ecological risk index ( ERI) was constructed based on the analysis of land use change and structural characteristics in urbanization watershed of Songhua River in Harbin section. Afterwards,the spatial distribution and change characteristics maps of ERI obtained by using block Kriging were analyzed to reveal the spatial and temporal evolution characteristics,change rules and formation mechanisms of ecological risk based on land use under the background of urbanization,and to minimize land use risk during urbanization process. The results showed that during the past 18 years,moderate ecological risk level was major,while proportion of high ecological risk was the lowest,and the area of higher and lower ecological risk region changed most greatly; high and higher ecological risk were focused on urban region and the transition zone from urban to suburban region,while low and lower ecological risk mainly distributed in forestland with higher vegetation coverage,water bodies,grassland,shrub land and so on. Meanwhile,the transition zone from high to low ecological risk was very obvious. In addition,ecological risk became slightly worse in some region due to the transformation from cropland to residential and urban land,while it became slightly better in other regions because of the transformation from cropland to forestland; the center of gravity in lower ecological risk region shifted most greatly,while the shift was the smallest in high ecological risk region,namely 12. 31 and 0. 57 km respectively. | Li YUAN Wenfeng GONG Yongfeng DANG Zexu LONG | 2013 | Asian Agricultural Research2013，5，3： | 7 |
| 20 | Quantum-inspired evolutionary tuning of SVM parameters显示文摘The most commonly used parameters selection method for support vector machines (SVM) is cross-validation, which needs a long- time complicated calculation. In this paper, a novel regularization parameter and a kernel parameter tuning approach of SVM are pre- sented based on quantum-inspired evolutionary algorithm (QEA). QEA with quantum chromosome and quantum mutation has better global search capacity. The parameters of least squares support vector machines (LS-SVM) can be adjusted using quantum-inspired evo- lutionary optimization. Classification and function estimation are studied using LS-SVM with wavelet kernel and Gaussian kernel. The simulation results show that the proposed approach can effectively tune the parameters of LS-SVM, and the improved LS-SVM with wavelet kernel can provide better precision. | Zhiyong Luo Ping Wang Yinguo Li Wenfeng Zhang Wei Tang Min Xiang | 2008 | Progress in Natural Science:Materials International2008，18，4： | 7 |
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