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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第3期35卷 449-454页

作者： Li Chenlu Sun Yufa wang zhonggen wang Guohua Key Laboratory of Intelligent Computing & Signal Processing Ministry of EducationAnhui University College of Electrical and Information Engineering Anhui University of Science and Technology

The multilevel characteristic basis function method(MLCBFM)with the adaptive cross approximation(ACA)algorithm for accelerated solution of electrically large scattering problems is studied in this paper.In the conventional MLCBFM based on Foldy-Lax multiple scattering equations,the improvement is only made in the generation of characteristic basis functions(CBFs).However,it does not provide a change in impedance matrix filling and reducing matrix calculation procedure,which is time-consuming.In reality,all the impedance and reduced matrix of each level of the MLCBFM have low-rank property and can be calculated efficiently.Therefore,ACA is used for the efficient generation of two-level CBFs and the fast calculation of reduced matrix in this study.Numerical results are given to demonstrate the accuracy and efficiency of the method.

关键词： multilevel characteristic basis function method(MLCBFM) adaptive cross approximation(ACA) characteristic basis functions(CBFs) electromagnetic scattering

Assessing the impacts of climate variability and human activities on streamflow in the water＇ source area of Baiyangdian Lake

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Journal of Geographical Sciences 2012年第5期22卷 895-905页

作者： HU Shanshan LIU Changming ZHENG Hongxing wang zhonggen YU Jingjie Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100049 China College of Water Sciences Beijing Normal University Beijing 100875 China

As the largest wetland in the North China Plain （NCP）, the Baiyangdian Lake plays an important role in maintaining water balance and ecological health of NCP. Ir the past few decades, the decreasing streamflow in the Baiyangdian Basin associated with climate vari- ability and human activities has caused a series of water and eco-environmer,tal issues. In this study, we quantified the impacts of climate variability and human activities on streamflow in the water source area of the Baiyangdian Lake, based on analyses of hydrologic changes of the upper Tanghe river catchment （a sub-basin of the Baiyangdian Basin） from 1960 to 2008. Climate elasticity method and hydrological modeling method were used to distinguish the effects of climate variability and human activities. The results showed that the annual streamflow decreased significantly （P〉0.05） by 1.7 mm/a and an abrupt change was identi- fied around the year 1980. The quantification results indicated that climate variations ac- counted for 38%-40% of decreased streamflow, while human activities accounted for 60%--62%. Therefore, the effect of human activities played a dominant role on the decline of the streamflow in the water source area of the Baiyangdian Lake. To keep the ecosystem health of the Baiyangdian Lake, we suggest that minimum ecological water demand and in- tegrated watershed management should be guaranteed in the future.

关键词： climate variability human activities climate elasticity hydrological model Baiyangdian Lake Tanghe River

Spatial and temporal variability of daily precipitation in Haihe River basin, 1958-2007

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Journal of Geographical Sciences 2010年第2期20卷 248-260页

作者： CHU Jianting XIA Jun XU Chongyu LI Lu wang zhonggen Key Laboratory of Water Cycle ＆ Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100039 China Institute of Physics ＆ Meteorology University of Hohenheim Garbenstr. 30 D-70955 Stuttgart Germany Department of Geosciences University of Oslo P O BOX 1047 Blindern N-0316 Oslo Norway

The seasonal variability and spatial distribution of precipitation are the main cause of flood and drought events. The study of spatial distribution and temporal trend of precipitation in river basins has been paid more and more attention. However, in China, the precipitation data are measured by weather stations （WS） of China Meteorological Administration and hydrological rain gauges （RG） of national and local hydrology bureau. The WS data usually have long record with fewer stations, while the RG data usually have short record with more stations. The consistency and correlation of these two data sets have not been well understood. In this paper, the precipitation data from 30 weather stations for 1958-2007 and 248 rain gauges for 1995-2004 in the Haihe River basin are examined and compared using linear regression, 5-year moving average, Mann-Kendall trend analysis, Kolmogorov-Smirnov test, Z test and F test methods. The results show that the annual precipitation from both WS and RG records are normally distributed with minor difference in the mean value and variance. It is statistically feasible to extend the precipitation of RG by WS data sets. Using the extended precipitation data, the detailed spatial distribution of the annual and seasonal precipitation amounts as well as their temporal trends are calculated and mapped. The various distribution maps produced in the study show that for the whole basin the precipitation of 1958-2007 has been decreasing except for spring season. The decline trend is significant in summer, and this trend is stronger after the 1980s. The annual and seasonal precipitation amounts and changing trends are different in different regions and seasons. The precipitation is decreasing from south to north, from coastal zone to inland area.

关键词： climate change spatial and temporal variability of precipitation Mann-Kendall method Kolmogorov-Smirnov test Z test F test Haihe River basin

Development of Hydro-Informatic Modelling System and its application

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Science China(Technological Sciences) 2008年第4期51卷 456-466页

作者： LIU ChangMing wang zhonggen ZHENG HongXing ZHANG Lu WU XianFeng Key Laboratory of Water Resources and Related Land Surface Processes Institute of Geographical Sciences and Natural ResourcesChinese Academy of SciencesBeijing 100101China College of Water Sciences Beijing Normal UniversityBeijing 100875China CSIRO Land and Water Christian LaboratoryGPO Box 1666CanberraA.C.T.2601Australia Environmental Protection Administration Beijing 100101China

The understanding of hydrological cycle is the core of hydrology and the scientific base of water resources management. Meanwhile, simulation of hydrological cycle has long been regarded as an important tool for the assessment, utilization and protection of water resources. In this paper, a new tool named Hydro-Informatic Modelling System (HIMS) has been developed and introduced with case studies in the Yellow River Basin in China and 331 catchments in Australia. The case studies showed that HIMS can be employed as an integrated platform for hydrological simulation in different regions. HIMS is a modular based framework of hydrological model designed for different utilization such as flood forecasting, water resources planning and evaluating hydrological impacts of climate change and human activities. The unique of HIMS is its flexibility in providing alternative modules in the simulation of hydrological cycle, which successfully overcome the difficulties in the availability of input data, the uncertainty of parameters, and the difference of rainfall-runoff processes. The modular based structure of HIMS makes it possible for developing new hydrological models by the users.

关键词： HIMS model customization hydrological cycle water resources

Evapotranspiration estimation methods in hydrological models

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Journal of Geographical Sciences 2013年第2期23卷 359-369页

作者： ZHAO Lingling XIA Jun XU Chong-yu wang zhonggen SOBKOWIAKLeszek LONG Cangrui KeyLaboratoryofWaterCycle&RelatedLandSurfaceProcesses.InstituteofGeographicSciencesandNaturalResourcesReseamh GASBeijing100101China GraduateUniversityofChineseAcademyofSciences Beijing100049China StateKeyLab.ofWaterResources&HydropowerEngineeringScience WuhanUniversityWuhan430072China DepartmentofGeosciences UniversityofOsloOsloNorway DepartmentofHydrologyandWaterManagement InstituteofPhysicalGeogmphyandEnvironmentalPlanningAdamMickiewiczUniversityPoznanPoland PuyangWaterConservancyBureau Puyang457000HenanChina

Actual evapotranspiration is a key process of hydrological cycle and a sole term that links land surface water balance and land surface energy balance. Evapotranspiration plays a key role in simulating hydrological effect of climate change, and a review of evapotranspiration estimation methods in hydrological models is of vital importance. This paper firstly summarizes the evapotranspiration estimation methods applied in hydrological models and then classifies them into the integrated converting methods and the classification gathering methods by their mechanism. Integrated converting methods are usually used in hydrological models and two differences exist among them： one is in the potential evaporation estimation methods, while the other in the function for defining relationship between potential evapora tion and actual evapotranspiration. Due to the higher information requirements of the Pen- man-Monteith method and the existing data uncertainty, simplified empirical methods for calculating potential and actual evapotranspiration are widely used in hydrological models. Different evapotranspiration calculation methods are used depending on the complexity of the hydrological model, and importance and difficulty in the selection of the most suitable evapotranspiration methods is discussed. Finally, this paper points out the prospective de velopment trends of the evapotranspiration estimating methods in hydrological modeling.

关键词： hydrological model actual evaporation potential evaporation function of soil moisture

Bayesian-combined wavelet regressive modeling for hydrologic time series forecasting

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Chinese Science Bulletin 2013年第27期58卷 3796-3805页

作者： SANG YanFang SHANG LunYu wang zhonggen LIU ChangMing YANG ManGen Key Laboratory of Water Cycle & Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Chinese Academy of Sciences School of Geographical Sciences Fujian Normal University

Wavelet regression(WR)models are used commonly for hydrologic time series forecasting,but they could not consider uncertainty evaluation.In this paper the AM-MCMC(adaptive Metropolis-Markov chain Monte Carlo)algorithm was employed to wavelet regressive modeling processes,and a model called AM-MCMC-WR was proposed for hydrologic time series forecasting.The AM-MCMC algorithm is used to estimate parameters’uncertainty in WR model,based on which probabilistic forecasting of hydrologic time series can be done.Results of two runoff data at the Huaihe River watershed indicate the identical performances of AM-MCMC-WR and WR models in gaining optimal forecasting result,but they perform better than linear regression models.Differing from the WR model,probabilistic forecasting results can be gained by the proposed model,and uncertainty can be described using proper credible interval.In summary,parameters in WR models generally follow normal probability distribution;series’correlation characters determine the optimal parameters values,and further determine the uncertain degrees and sensitivities of parameters;more uncertain parameters would lead to more uncertain forecasting results and hard predictability of hydrologic time series.

关键词：时间序列预测水文时间序列回归建模小波线性回归模型贝叶斯 MCMC算法合并

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基于变速趋近律的PMSM复合速度控制

制造技术与机床 2024年第6期 95-101页

作者：朱小兵王仲根高晓嵩安徽理工大学电气与信息工程学院安徽淮南232001

为了提高永磁同步电机速度控制器的性能,文章提出一种新型变速趋近律滑模控制策略。变速趋近律在传统指数趋近律的基础上引入关于系统状态的幂次项和关于滑模函数的变速项,并采用双曲正切函数来减小高频切换项的影响。该控制策略有利于... 详细信息

为了提高永磁同步电机速度控制器的性能,文章提出一种新型变速趋近律滑模控制策略。变速趋近律在传统指数趋近律的基础上引入关于系统状态的幂次项和关于滑模函数的变速项,并采用双曲正切函数来减小高频切换项的影响。该控制策略有利于减小电流和转矩脉动,提高了系统运行的稳定性和响应速度。另外,针对系统受未知干扰影响的问题,设计了一种滑模扰动观测器来估计系统的总扰动,并将估计的扰动补偿到复合速度控制器中。最后,利用Matlab/Simulation仿真和电机实验平台对所提出的控制策略进行验证。仿真和实验结果表明,复合速度控制器与扰动观测器相结合的控制策略具有更快的收敛速度、更小的抖振和更好的抗扰性能。

关键词：永磁同步电机滑模控制变速趋近律扰动观测器

CFRP-木结构波纹钢填板螺栓节点力学性能正交试验研究

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浙江大学学报（工学版） 2024年第4期58卷 847-856页

作者：郭轩徐忠根赵亚涛钟丹云广州大学土木工程学院广东广州510006

为了明确异型截面钢填板对节点性能的影响,为木结构异型钢填板螺栓节点提供安全性的设计经验,提出CFRP-木结构波纹钢填板螺栓节点,在正交试验设计条件下开展单轴顺纹拉伸试验研究.试验发现,节点具有多种受力特征,包括木构件剪切破坏、... 详细信息

为了明确异型截面钢填板对节点性能的影响,为木结构异型钢填板螺栓节点提供安全性的设计经验,提出CFRP-木结构波纹钢填板螺栓节点,在正交试验设计条件下开展单轴顺纹拉伸试验研究.试验发现,节点具有多种受力特征,包括木构件剪切破坏、顺纹向张开型断裂(TL断裂)、端部顺纹压溃、CFRP断裂和螺栓弯折等形式;节点在受力过程中没有明显屈服阶段,主要经历线弹性阶段、断裂失效过渡阶段和断裂失效阶段.通过正交参数分析得到不同因素对所提节点主要力学性能的影响程度及规律.结果表明:各因素对极限强度和延性的影响比对弹性刚度的影响显著,且波角和波高为主要影响因素.极限强度与波角负相关且随着波高的增大呈波动变化,延性与波角和波高负相关.

关键词：木结构波纹钢填板螺栓节点 CFRP 正交试验

高职院校服务技能型社会建设的困境、动力与机制

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教育与职业 2024年第8期1056卷 30-36页

作者：陈新文陈忠根襄阳职业技术学院湖北襄阳441050

在技能型社会建设中,高职院校被赋予重要的责任和使命。当前高职院校服务技能型社会建设面临思想与文化的桎梏、实践与政策的局限、主体与要素的缺失等问题。高职院校服务技能型社会建设的重点在于在发展目标中寻找共同点、在发展路径... 详细信息

在技能型社会建设中,高职院校被赋予重要的责任和使命。当前高职院校服务技能型社会建设面临思想与文化的桎梏、实践与政策的局限、主体与要素的缺失等问题。高职院校服务技能型社会建设的重点在于在发展目标中寻找共同点、在发展路径中寻找契合点、在发展重点中寻找融合点。其内生动力主要表现在三个方面:体现本质性的技能供给力、突出类型化的跨界融合力和增强适应性的质量保障力。其需要的有效服务机制包括多元协同、市场响应、职能再建和主体优先四种,从而凝聚内外合力,提升供给效能,强化育训一体,凸显终极价值。

关键词：高职院校技能型社会建设内生动力有效机制

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量子思维应用于音位研究初探

外国语文 2024年第3期40卷 30-40页

作者：于中根张学丽北京语言大学外国语学部英语学院北京100083 河北科技师范学院外国语学院河北秦皇岛066004

量子思维与音位研究的历史可以追溯到20世纪初量子力学的发现。随着时间的推移,这两个领域的研究逐渐联系起来,形成了量子音位学理论。量子思维为音位研究提供了一种新的分析和解释方式。然而,国内外仍欠缺关注量子思维应用于音位的研... 详细信息

量子思维与音位研究的历史可以追溯到20世纪初量子力学的发现。随着时间的推移,这两个领域的研究逐渐联系起来,形成了量子音位学理论。量子思维为音位研究提供了一种新的分析和解释方式。然而,国内外仍欠缺关注量子思维应用于音位的研究。通过引入连续性、不确定性、超位置、纠缠和相干等量子思维的概念,传统的二分法对音位的理解可以得到深化和扩展。量子力学的数学模型和工具可以更好地描述音位之间的连续性和交叉现象,更好揭示复杂语言中音位的组织方式,并探索语言中微观规律和特征,并为音位学研究提供新的视角。然而,量子思维在音位研究中的应用尚处于初级阶段,仍需进行更多的实证研究和理论探索来验证和完善这一方法。

关键词：音位连续性不确定性超位置纠缠

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