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水电站水库库容特性解析与建模研究

长江科学院院报 2024年第2期41卷 37-43页

作者：贾本军汤正阳曹辉郭乐张海荣任家朋中国长江电力股份有限公司智慧长江与水电科学湖北省重点实验室湖北宜昌443133 华中科技大学土木与水利工程学院湖北宜昌430074 中国三峡武汉科创园工业控制系统科技创新中心武汉430070

针对水库库容特性的函数化表征问题,通过对水库的形态特征进行抽象,构建了描述水库一般性形态特征的三棱锥模型和不规则锥体模型,在此基础上采用数学积分方法推导出表征水库库容特性的三参数幂函数模型,并根据水库库容特性的数学性质,... 详细信息

针对水库库容特性的函数化表征问题,通过对水库的形态特征进行抽象,构建了描述水库一般性形态特征的三棱锥模型和不规则锥体模型,在此基础上采用数学积分方法推导出表征水库库容特性的三参数幂函数模型,并根据水库库容特性的数学性质,给出了三参数幂函数的参数取值范围,最后以长江中上游流域37座水库为研究对象,通过合理性分析和拟合优度评价,证明了三参数幂函数是一种适用性广、可靠性高、物理意义明确的水库库容特性表征函数。研究成果可为水电站水库发电精细化调度提供基础函数曲线支撑。

关键词：水电站水库水库库容特性函数拟合拟合优度分析三参数幂函数

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发达国家青少年体育赛事体系建设经验及启示

体育文化导刊 2024年第7期 75-81页

作者：夏锐张梓正张朕苏家本王燕巢湖学院体育学院合肥238024 浙江工商大学体育工作部杭州310018

运用文献资料、逻辑分析等方法,从服务对象、治理主体、治理内容和价值功能剖析发达国家青少年体育赛事体系建设概况、经验,并提出对我国的启示。经验:始终坚持赛事面向人人理念,着力推进多元主体共治机制,提倡强化重点体育要素治理,注... 详细信息

运用文献资料、逻辑分析等方法,从服务对象、治理主体、治理内容和价值功能剖析发达国家青少年体育赛事体系建设概况、经验,并提出对我国的启示。经验:始终坚持赛事面向人人理念,着力推进多元主体共治机制,提倡强化重点体育要素治理,注重释放多元价值功能。启示:持续优化青少年体育赛事系统,着重构建多元主体合力,重新定位要素治理需求,科学开发体育赛事功能。

关键词：竞技体育青少年体育赛事体系建设发达国家

Revealing the interlaminar shear failure behavior of unidirectional laminate under combined compression-shear loads

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Journal of Materials Science & Technology 2023年第26期157卷 110-119页

作者： Yueran Zhao jian Zang ben jia Junchao Yang Xiaopeng Wan Wenzhi Wang Xiangming Chen School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Aircraft Strength Research Institute of China Xi’an 710065China

Due to the coupling effects between stresses in different directions,the mechanical behavior of an ad-vanced composite material under multiaxial loading is extremely *** this study,the influence of through-thickness compressive stress on the interlaminar shear performance of a carbon fiber-reinforced composite was experimentally *** cylindrical unidirectional laminate specimens were fabricated to conduct combined compression-shear tests,and the fracture morphologies of the specimens were characterized to reveal their failure *** results indicate that a moderate compression load significantly enhanced the shear properties of the laminate by inhibiting crack propagation and improv-ing the friction *** shear strength and modulus of a laminate specimen subjected to combined stresses improved up to a maximum of 76%and 231%,respectively,over those of an equivalent specimen subjected to pure ***,as the applied through-thickness load approached the compressive strength of the laminate,the specimen shear capacity began to decline owing to the transition of frac-ture ***,the specimens exhibited mixed failure modes corresponding to the different stress states,which were induced by the combined effects of through-thickness compressive and shear *** the applied through-thickness compressive stress increased,the dominant failure mode of the laminate specimen changed from fiber-matrix debonding to fiber shearing and then to fiber break-age,resulting in various shear performances.

关键词： Fiber-reinforced composites Mechanical behavior Multiaxial loading Failure analysis

基于神经网络的天文台址长期白日视宁度变化估算

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天文学报 2024年第4期65卷 79-86页

作者：胡兴杨尚斌邓元勇林佳本包星明王全中国科学院国家天文台北京100101 中国科学院大学北京100049

视宁度好坏是影响天文观测图像质量的一个决定性因素,目前白日视宁度数据主要是通过太阳差分像运动视宁度检测仪(Solar Differential Image Motion Monitor,SDIMM)或者谱比法获得.由于SDIMM和实际观测所用仪器不同,其测得的视宁度无法... 详细信息

视宁度好坏是影响天文观测图像质量的一个决定性因素,目前白日视宁度数据主要是通过太阳差分像运动视宁度检测仪(Solar Differential Image Motion Monitor,SDIMM)或者谱比法获得.由于SDIMM和实际观测所用仪器不同,其测得的视宁度无法反映数据获取时刻的实际视宁度情况,也无法回溯历史既有观测数据对应的大气视宁度.而使用谱比法需要海量短曝光数据,计算成本巨大.基于以上天文观测面临的困难,提出了一种基于神经网络的白日视宁度估算方法,该方法首先对获得的短曝光数据使用谱比法计算对应的视宁度r_(0),构建数据集;然后采用主成分分析的方法对数据进行降维,通过神经网络建立起窄带滤光器太阳光球观测图像和视宁度之间的非线性回归关系,训练集和测试集实验的结果表明该方法可以用于估算视宁度.使用该方法对怀柔观测基地2020年的视宁度进行估算,视宁度中值为2.89 cm,对1989年到2010年连续22 yr的历史观测数据进行长周期的视宁度统计分析,结果表明怀柔基地发布的历史数据对应的视宁度中值在3 cm左右,40%以上数据对应的视宁度超过3 cm,一年中9月份的视宁度最好,该结果验证了怀柔基地视宁度的长期稳定性.此外,该方法也可以从视宁度r_(0)的快速判断出发,为采集到的高质量短曝光图像甄选提供判断依据.

关键词：湍流:视宁度方法:数据分析方法:神经网络

High-strength hydrogels:Fabrication,reinforcement mechanisms,and applications

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Nano Research 2023年第2期16卷 3475-3515页

作者： Heyuan Huang Zhicheng Dong Xiaoyang Ren ben jia Guowei Li Shaowen Zhou Xin Zhao Wenzhi Wang School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China School of Civil Aviation Northwestern Polytechnical UniversityXi’an 710072China State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China Department of Periodontology College of StomatologyXi’an Jiaotong UniversityXi’an 710049China

With the continuous appearance and expansion of high-strength hydrogels in emerging fields such as industry,medicine,and green development,the synthesis and application of high-strength hydrogels have developed dramatically and achieved remarkable results from the aspects of raw materials,preparation methods,and reinforcement ***,there is still a lack of systematic reviews on high-strength ***,we first discuss the advantages of natural and synthetic materials,and the characteristics of high-strength hydrogels prepared from different raw materials;we then expound on the influence mechanism of physical interactions or chemical bonds on the strength of the hydrogel from three aspects:physical cross-linking,chemical cross-linking,and dynamic chemical cross-linking;at last,we systematically expound the strengthening strategies,including double network/multi-network,nanocomposite,topology,supramolecular polymerization,and characteristics and strengthening mechanisms of such high-strength *** addition,based on the development status of high-strength hydrogels,we combined the application requirements and the existing drawbacks of high-strength hydrogels to propose their possible development directions in the future.

关键词： high-strength hydrogels raw materials for hydrogels cross-linking methods strengthening strategies applications

A New Multiplicity Formula for the Weyl Modules of Type B and C

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Journal of Mathematical Research and Exposition 2010年第4期30卷 675-686页

作者： jia Chen YE ben Sheng YUN jia ZHAN Department of Mathematics Tongji University Shanghai 200092 P. R. China

A monomial basis and a filtration of subalgebras for the universal enveloping algebra U（gl） of a complex simple Lie algebra gl of type Bl and Cl are given, and the decomposition of the Weyl module V （λ） as a U（gl）-module into a direct sum of Weyl modules V （μ）’s as U（gl-1）modules is described. In particular, a new multiplicity formula for the Weyl module V （λ） is obtained in this note.

关键词： simple Lie algebra multiplicity formula weight irreducible module.

Research on the principle of space high-precision temperature control system of liquid crystals based Stokes polarimeter

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Research in Astronomy and Astrophysics 2021年第1期21卷 97-104页

作者： Xin-Wei Zhang Yang Zhang jia-ben Lin Jun-Feng Hou Yuan-Yong Deng Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 101408China

The magnetic field is one of the most important parameters in solar physics,and a polarimeter is the key device to measure the solar magnetic *** crystals based Stokes polarimeter is a novel technology,and will be applied for magnetic field measurement in the first space-based solar observatory satellite developed by China,Advanced Space-based Solar ***,the liquid crystals based Stokes polarimeter in space is not a mature ***,it is of great scientific significance to study the control method and characteristics of the *** retardation produced by a liquid crystal variable retarder is sensitive to the temperature,and the retardation changes 0.09°per 0.10℃.The error in polarization measurement caused by this change is 0.016,which affects the accuracy of magnetic field *** order to ensure the stability of its performance,this paper proposes a high-precision temperature control system for liquid crystals based Stokes polarimeter in *** order to optimize the structure design and temperature control system,the temperature field of liquid crystals based Stokes polarimeter is analyzed by the finite element method,and the influence of light on the temperature field of the liquid crystal variable retarder is analyzed *** analyzing the principle of highprecision temperature measurement in space,a high-precision temperature measurement circuit based on integrated operational amplifier,programmable amplifier and 12 bit A/D is designed,and a high-precision space temperature control system is developed by applying the integral separation PI temperature control algorithm and PWM driving heating *** experimental results show that the effect of temperature control is accurate and stable,whenever the liquid crystals based Stokes polarimeter is either in the air or *** temperature stability is within±0.0150℃,which demonstrates greatly improved stability for the liquid crystals based Stokes polarim

关键词： liquid crystals based Stokes polarimeter high-precision temperature measurement space high-precision temperature control temperature field analysis PID control

腹腔镜胃袖状切除术治疗肥胖合并2型糖尿病及脂肪胰的临床研究

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中华普外科手术学杂志（电子版） 2024年第5期18卷 554-557页

作者：李猛姜腊董磊吴情贾犇黎皖北煤电集团总医院胃肠外科安徽宿州234000 皖北煤电集团总医院中心实验室安徽宿州234000 安徽医科大学第二附属医院胃肠外科合肥230601

目的:探究腹腔镜胃袖状切除术(LSG)治疗肥胖合并2型糖尿病及脂肪胰的临床效果。方法:回顾性分析2021年1月至2022年10月行LSG治疗的63例肥胖合并2型糖尿病及脂肪胰患者临床资料,分析手术前后减重效果、代谢指标及胰腺功能指标变化情况,... 详细信息

目的:探究腹腔镜胃袖状切除术(LSG)治疗肥胖合并2型糖尿病及脂肪胰的临床效果。方法:回顾性分析2021年1月至2022年10月行LSG治疗的63例肥胖合并2型糖尿病及脂肪胰患者临床资料,分析手术前后减重效果、代谢指标及胰腺功能指标变化情况,统计术后12个月患者2型糖尿病、脂肪胰及其他合并症缓解情况。采用SPSS 25.0分析数据。物理指标、血糖和血脂代谢指标等计量资料以(x±s)表示,采用配对样本t检验;合并症情况等计数资料以[例(%)]表示。P<0.05为差异有统计学意义。结果:与术前比较,术后6个月、12个月患者体重、体重指数(BMI)、多余体重减轻百分比(EWL%)、腰围、臀围、收缩压、舒张压等物理指标及空腹血糖(FPG)、糖化血红蛋白(HbA1c)、空腹胰岛素(FINS)、总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白(LDL-C)、高密度脂蛋白(HDL-C)等血糖、血脂代谢指标呈下降趋势,且术后12个月各指标水平显著低于术后6个月(P<0.05);与术前比较,术后6个月、12个月患者胰岛素抵抗指数(Homa-IR)明显降低,胰岛β细胞功能(Homa-β)水平明显升高,且术后12个月Homa-IR显著低于术后6个月,术后12个月Homa-β水平明显高于术后6月(P<0.05)。至术后12个月,2型糖尿病的缓解率为71.4%,合并症脂肪胰、高血压、高血脂症缓解率分别达到了82.5%、77.8%、81.8%。结论:LSG治疗肥胖合并2型糖尿病及脂肪胰安全有效,可达到明显的减重效果,同时可改善血糖、血脂等代谢情况及胰腺功能,且术后多数患者可达到糖尿病缓解和脂肪胰缓解。

关键词：腹腔镜胃袖状切除术肥胖 2型糖尿病脂肪胰

Evolution of isolated G-band bright points: size, intensity and velocity

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Research in Astronomy and Astrophysics 2014年第6期14卷 741-752页

作者： Yun-Fei Yang jia-ben Lin Song Feng Kai-Fan Ji Hui Deng Feng Wang Faculty of Information Engineering and Automation/Yunnan Key Laboratory of Computer Technology Application Kunming University of Science and Technology Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences Key Laboratory of Modern Astronomy and Astrophysics Nanjing University Ministry of Education

We study the evolution pattern of isolated G-band bright points （GBPs） in terms of their size, intensity and velocity. Using a high resolution image sequence taken with the Hinode/Solar Optical Telescope （SOT）, we detect GBPs in each image by the Laplacian and Morphological Dilation algorithm, and track their evolutions by a 26-adjacent method in a three-dimensional space-time cube. For quantifying the evolution, we propose a quantification method based on lifetime normalization which aligns the different lifetimes to common stages. The quantification results show that, on average, the diameter of isolated GBPs changes from 166 to 173 km, then down to 165 km; the maximum intensity contrast changes from 1.012 to 1.027, then down to 1.011; however, the velocity changes from 1.709 to 1.593 km s-1, then up to 1.703 km s-i. The results indicate that the evolution follows a pattern such that the GBP is small, faint and fast-moving at the birth stage, becomes big, bright and slow-moving at the middle stage, then gets small, faint and fast-moving at the decay stage until disappearance. Although the differences are very small, a two-sample t-test is used to demonstrate there are significant differences in means between the distri- butions of the different stages. Furthermore, we quantify the relationship between the lifetimes of GBPs and their properties. It is found that there are positive correlations between the lifetimes and their sizes and intensities with correlation coefficients of 0.83 and 0.65, respectively; however, there is a negative correlation between the life- times and velocities with a correlation coefficient of-0.49. In summary, the longer the GBP persists, the bigger, brighter and slower it will be.

关键词： techniques: image processing -- Sun: photosphere -- methods: dataanalysis -- methods: statistical