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高水平摔跤运动员关键技战术指标特征研究

体育科技文献通报 2024年第1期32卷 39-42,73页

作者：白银川陈辉许奎元周胜银刘卫军国家体育总局体育科学研究所北京100061 长沙医学院体育健康学院湖南长沙410219 重庆第二师范学院重庆400065 北京体育大学北京100084

采用录像分析法、数理统计法对2019年世界摔跤锦标赛、2020东京奥运会和2022年世界摔跤锦标赛冠军运动员的关键技战术指标进行统计和分析,揭示冠军运动员关键技战术指标对运动成绩的影响程度,归纳关键技战术指标的特征,为摔跤运动训练... 详细信息

采用录像分析法、数理统计法对2019年世界摔跤锦标赛、2020东京奥运会和2022年世界摔跤锦标赛冠军运动员的关键技战术指标进行统计和分析,揭示冠军运动员关键技战术指标对运动成绩的影响程度,归纳关键技战术指标的特征,为摔跤运动训练实践提供参考。结果表明:(1)双肩获胜(VT)次数与运动成绩似乎无关(r=0.134,p=0.183>0.05),技术优势获胜(ST)次数(r=0.368,p<0.01)和防守效率(r=0.412,p<0.01)与运动成绩呈显著正相关,进攻效率(r=-0.326,p=0.001<0.01)和技术全面性(r=-0.552,p<0.01)与运动成绩呈显著负相关。(2)男子、女子自由式和男子古典式冠军运动员在比赛中均表现出了较高的技术优势获胜(ST)次数、进攻、防守和全面的技术动作使用能力,进攻效率、防守效率和技术全面性呈现出整体上升的态势。(3)在进攻能力和技术动作使用能力相当时,防守能力和技术动作成功率是决定运动员最终运动成绩的关键。

关键词：高水平摔跤项目技战术指标运动成绩关联性

Experimental Study on Purification Efficiency of Air Purifier for the Indoor Total Volatile Organic Compounds

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Meteorological and Environmental Research 2016年第3期7卷 38-41页

作者： Xiao Jiangrong zhou shengyin Peng Tianyou Li Liangliang Hubei Provincial Supervision Inspection Research Institute for Products Quality Wuhan 430061 China College of Chemistry and Molecular Sciences Wuhan University Wuhan 430072 China

By using total volatile organic compounds （TVOC） as the objective volatile pollutant, the purification efficiency of some representative air purifiers bought in the market was determined under the relatively independent and stable environmental conditions supplied by the self-made multi- functional environmental test chamber. Various evaluation parameters of TVOC were calculated based on the tested results, such as purification ef- ficiency and removal rate. The results showed that the TVOC purification efficiency increased with enhancing the temperature or lessening the rela- tive humidity, but this effect is not obvious. The air purifiers which use photocatalytic technology have higher TVOC purification efficiency than those which only use some adsorption technology. The purification efficiency and removal rate can be more accurate to evaluate the purification efficiency of air purifiers.

关键词： Air purifier Environmental test chamber Purification efficiency TVOC China

The Application of the Steel Slag in the Radiation Shield Heavy Concrete

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The Application of the Steel Slag in the Radiation Shield He...

Design And Preparation Of Cement-based Composite with Electromagnetic Protection

中国材料大会2012

作者： Ruguang Li shengyin zhou Kun Tian Peng Yao National Energy-Saving Construction Material Quality Supervision Inspection Center

ISBN: (纸本)9783037856062

The steel slag was broken into steel slag powders and sands. The performance of the radiation shield heavy concrete was studied in this work by mixing different content of steel slag sand and powder. The results showed that the water requirement of normal consistency and setting time increased with the increase of the content of the steel slag powder. The strength reduced in the early stage of the experiment. The strength increased firstly and decreased later. The optimal content of steel slag powder for strength was 20%. For the steel slag powder and sand, whether the concrete added one or two components, the concrete slump loss increased and strength reduced at 3 days. The steel slag powder and sand added into concrete improved the performance of the concrete effectively, solved the heavy aggregate subsidence and improved the concrete homogenous.

关键词： Steel slag powder Steel slag sand Working performance Homogeneous.

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Design And Preparation Of Cement-based Composite with Electr...

热处理对烧结NdFeB磁体微观结构和磁性能的影响

中国材料大会2012

作者： Kun Tian shengyin zhou Jiangrong Xiao Ruguang Li Peng Yao National Energy-Saving Construction Material Quality Supervision Inspection Center

ISBN: (纸本)9783037856062;3037856068

Using space electromagnetic wave propagation principle, environment requirements of building protective engineering structure and performance characteristics of cement-based composites, a design idea of cement-based composite with electromagnetic protection is presented in the present study. This design idea was tested and verified. According to the proposed new designed method, by optimizing and selecting the wave-transparent aggregate and absorbing agent material, the absorbing composite materials of cement-based electromagnetic protection, electromagnetic wave absorbent, energy saving and environmental protection can be improved. A new cement-based composite with electromagnetic protection and microwave absorbing properties （the minimum reflectivity is -8.4dB）, wide frequency bandwidth, and letter mechanical properties was prepared by using a 20 mm sample between 8-18 GHz. The results provide a basis design and preparation of cement-based composite with electromagnetic protection.

关键词： Electromagnetic protection Cement-based Composite.

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稀有金属材料与工程 2006年第6期35卷 1006-1008页

作者：周圣银周廉陈绍楷罗建军陕西科技大学陕西咸阳712081 西北有色金属研究院陕西西安710016

系统研究了热处理对烧结NdFeB磁体微观结构和磁性能的影响。结果表明:二级回火热处理后,磁体微观组织结构得到明显改善,晶界变得更加规整、平滑,富Nd相均匀弥散地分布于晶粒周围,晶界相成分趋于稳定、均匀;磁体的内禀矫顽力显著提高,剩... 详细信息

系统研究了热处理对烧结NdFeB磁体微观结构和磁性能的影响。结果表明:二级回火热处理后,磁体微观组织结构得到明显改善,晶界变得更加规整、平滑,富Nd相均匀弥散地分布于晶粒周围,晶界相成分趋于稳定、均匀;磁体的内禀矫顽力显著提高,剩磁及最大磁能积也有一定程度的提高,极大地改善了磁体的热稳定性。

关键词：热处理微观结构磁性能烧结NdFeB磁体热稳定性

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关于女子摔跤运动员体能训练的探讨

当代体育科技 2021年第34期11卷 34-37页

作者：周胜银北京体育大学北京100084

摔跤运动作为我国奥运赛场的主要夺金点,需要相关团队做好竞技体育重点项目训练工作。近年来国际摔跤比赛规则发生了改变,为了适应当前的比赛规则,摔跤训练需要作出适当调整,对体能训练模式作出创新与改变,使体能训练方式与女子摔跤的... 详细信息

摔跤运动作为我国奥运赛场的主要夺金点,需要相关团队做好竞技体育重点项目训练工作。近年来国际摔跤比赛规则发生了改变,为了适应当前的比赛规则,摔跤训练需要作出适当调整,对体能训练模式作出创新与改变,使体能训练方式与女子摔跤的特点更加适应,全面提高女子摔跤运动员的体能。该文主要分析新规则对女子摔跤体能训练产生的影响,根据新规则对女子摔跤运动员提出的全新要求,为体能训练模式的优化提出建议。

关键词：女子摔跤体能训练运动员力量速度

关于GB/T23936-2018工业氟硅酸钠含量测定的改进

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当代化工研究 2019年第12期 1-3页

作者：周胜银周亮周茜湖北省产品质量监督检验研究院湖北430061 湖北特种设备检验检测研究院湖北430077

通过化学反应原理和实验条件推导出国家现行有效标准中计算公式引用的系数错误所在,并加以纠正;系统分析了测试过程关键控制点,提出了改进措施;全面规范了标准中公式不规范描述所带来的困惑;解决了检测人员检测难、检不准问题.通过试样... 详细信息

通过化学反应原理和实验条件推导出国家现行有效标准中计算公式引用的系数错误所在,并加以纠正;系统分析了测试过程关键控制点,提出了改进措施;全面规范了标准中公式不规范描述所带来的困惑;解决了检测人员检测难、检不准问题.通过试样验证,改进方法切实可行,已用于检测一线实际操作.

关键词：氟硅酸钠含量改进

Parallel Physics-Informed Neural Networks Method with Regularization Strategies for the Forward-Inverse Problems of the Variable Coefficient Modified KdV Equation

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Journal of Systems Science & Complexity 2024年第2期37卷 511-544页

作者： zhou Huijuan School of Science Shanghai Maritime UniversityShanghai 201306China

This paper mainly introduces the parallel physics-informed neural networks(PPINNs)method with regularization strategies to solve the data-driven forward-inverse problems of the variable coefficient modified Korteweg-de Vries(VC-MKdV)*** the forward problem of the VC-MKdV equation,the authors use the traditional PINN method to obtain satisfactory data-driven soliton solutions and provide a detailed analysis of the impact of network width and depth on solving accuracy and ***,the author finds that the traditional PINN method outperforms the one with locally adaptive activation functions in solving the data-driven forward problems of the VC-MKdV *** for the data-driven inverse problem of the VC-MKdV equation,the author introduces a parallel neural networks to separately train the solution function and coefficient function,successfully addressing the function discovery problem of the VC-MKdV *** further enhance the network’s generalization ability and noise robustness,the author incorporates two regularization strategies into the *** amount of numerical experimental data in this paper demonstrates that the PPINNs method can effectively address the function discovery problem of the VC-MKdV equation,and the inclusion of appropriate regularization strategies in the PPINNs can improves its performance.

关键词： Data-driven forward-inverse problems parallel physics-informed neural networks regularization strategies variable coefficient modified KdV equation

Influence of stearic acid surface modification on flowability and agglomeration of battery grade Li_(2)CO_(3)powder

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Particuology 2024年第9期92卷 263-277页

作者： Ming zhou Lithium Industry Center Zhejiang New Era Zhongneng Technology Co.Ltd.Shaoxing312000China

This work investigates the flow and agglomeration behaviors of battery grade Li_(2)CO_(3)powder and the influence of stearic acid surface *** degree of agglomeration is directly related to the uniformity of Li_(2)CO_(3)and its powder *** to the Chinese National Nonferrous Metal Industry Standard,battery grade Li_(2)CO_(3)powder has D50 equal to 3–8μm which belongs to a micron-sized superfine ***,with the extension of storage time,the serious agglomeration phenomenon occurs due to the large specific surface area and rough and irregular powder *** Hausner ratio(HR)of the unmodified sample increases from 1.14 to 1.41,and the corresponding flowability is classified as good to ***,among samples with doping stearic acid,the optimum amount of it is 0.10 wt%which exhibits an extremely stable HR value from 1.14 to ***,after 156 days,the repose angle(AR)obtained for samples without surface modification and using 0.10 wt%stearic acid are calculated to be 49°and 28°,*** on the values of HR and AR,the flowability of the unmodified sample is poor while the sample modified with 0.10 wt%of stearic acid still maintain excellent powder flow ***,The LiMn_(2)O_(4)cathode material synthesized from modified Li_(2)CO_(3)powder with a stearic acid content of 0.10 wt%exhibits good crystallinity and comparable electrochemical performance to that prepared by commercial Li_(2)CO_(3).These results indicate that stearic acid has the potential to be an ideal modifier for battery grade Li_(2)CO_(3)powder that needs to be kept for a long time.

关键词： Battery grade Li_(2)CO_(3)powder Flowability Surface modification Stearic acid