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足式机器人SLIP模型向上跳跃台阶的运动控制

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控制理论与应用 2024年第4期41卷 631-637页

作者：肖乐伞红军孙海杰陈久朋昆明理工大学机电工程学院云南昆明650500 云南省先进装备智能制造技术重点实验室云南昆明650500

由于存在地势起伏,台阶对足式机器人运动稳定性会带来较大挑战.弹簧负载倒立摆模型(SLIP)作为研究足式机器人的优良模板,能否完成向上跳跃台阶的动作与其腿部摆角,起跳位置和跳跃高度都有密切的关系.由于调整模型腿部摆角规律容易引发... 详细信息

由于存在地势起伏,台阶对足式机器人运动稳定性会带来较大挑战.弹簧负载倒立摆模型(SLIP)作为研究足式机器人的优良模板,能否完成向上跳跃台阶的动作与其腿部摆角,起跳位置和跳跃高度都有密切的关系.由于调整模型腿部摆角规律容易引发运动失效,故本文在算法中引入虚拟弹簧腿,根据虚拟弹簧腿的运行规律确定合理起跳位置,根据起跳位置来控制系统跳跃高度进而完成跳跃台阶的动作.最后利用仿真软件进行多组仿真,结果表明本文算法对起跳区间划分合理,对起跳高度控制精准,能够实现SLIP模型跳跃台阶前后的稳定运动.

关键词：足式机器人运动控制 SLIP模型台阶地形能量补充

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钙基脱氯剂脱除重整高温烟气中HCl的研究

辽宁化工 2024年第1期53卷 65-67,73页

作者：刘聪单红飞沈阳三聚凯特催化剂有限公司辽宁沈阳110144

重整催化剂的再生过程主要为:卸料、烧焦、氧氯化、焙烧、冷却、隔离等步骤,其中烧焦和氧氯化为关键步骤。重整催化剂运行一定时间因表面积碳结焦而失活,“烧焦”是在氧气存在和高温条件下将催化剂上的积碳转化为二氧化碳,随着循环气带... 详细信息

重整催化剂的再生过程主要为:卸料、烧焦、氧氯化、焙烧、冷却、隔离等步骤,其中烧焦和氧氯化为关键步骤。重整催化剂运行一定时间因表面积碳结焦而失活,“烧焦”是在氧气存在和高温条件下将催化剂上的积碳转化为二氧化碳,随着循环气带走,此过程中也伴随着催化剂上的关键组分氯的脱附,并以氯化氢的形式存在于循环气中。钙系脱氯剂使用精度高,脱氯效果好,在市场上广泛应用。实验以氢氧化钙和碳酸钙为主要活性组分,辅助加入其他提高脱氯效果的金属元素,增加金属直接协同作用,达到提高脱氯效果的目的。采用滚球成型的方式,对脱氯剂进行成型,可以有效保护活性组分的孔结构,通过脱氯评价对实验结果验证,使用后样品的氯含量可达36%以上。

关键词：高温烟气脱氯剂钙基

小学班级管理中的不当标签行为:表现、危害、成因与对策

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黄冈师范学院学报 2024年第2期44卷 58-63页

作者：童三红翟文静黄冈师范学院教育学院湖北黄冈438000

小学阶段是学生身心快速发展的关键期,然而在班级管理中却存在着“嘲讽化”“分层化”“圈层化”“污名化”等各式各样贴不当标签的现象。这些不当标签行为影响学生身心健康发展、破坏班级集体氛围、降低学校声誉。分析认为,教师教育理... 详细信息

小学阶段是学生身心快速发展的关键期,然而在班级管理中却存在着“嘲讽化”“分层化”“圈层化”“污名化”等各式各样贴不当标签的现象。这些不当标签行为影响学生身心健康发展、破坏班级集体氛围、降低学校声誉。分析认为,教师教育理念陈旧,管理方式落后;归因倾向不合理,价值取向不良;评价机制不健全、评价主体单一是造成小学班级中不当标签的成因。要解决不当标签问题,需要班级管理者更新教育理念,转变管理方式;提高教师素养,纠正归因偏差;健全评价机制,倡导多元评价。

关键词：小学班级管理标签理论不当标签行为

Quantum chemical study on the thermal rearrangements of HNCRCR'CO

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Chinese Journal of Chemistry 1996年第2期14卷 105-108页

作者： LI,Yong-hong hong,san-GuoDepartment of Chemistry,Jiangxi Normal University,Nanchang,Jiangxi 330017,China Department of Chemistry Jiangxi Normal University Nanchang Jiangxi 330027 China

MINDO/3 molecular orbital theory has been used to study the thermal rearrangements of HNCRCR'*** results obtained show that the activation energy of this rearrangement depends on the migrating group R and the group R'.

关键词： Thermal rearrangement MINDO/3 MO method transition state intrinsic reaction coordinate (IRC)

A seismic elastic moduli module for the measurements of low-frequency wave dispersion and attenuation of fluid-saturated rocks under different pressures

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Petroleum Science 2024年第1期21卷 162-181页

作者： Yan-Xiao He Shang-Xu Wang Gen-Yang Tang Chao Sun hong-Bing Li san-Yi Yuan Xian Wei Li-Deng Gan Xiao-Feng Dai Qiang Ge Peng-Peng Wei Hui-Qing Zhang National Key Laboratory of Petroleum Resources and Engineering CNPC Key Lab of Geophysical ExplorationCollege of GeophysicsChina University of Petroleum(Beijing)Beijing102249China School of Resources and Geosciences China University of Mining and TechnologyXuzhou221116JiangsuChina Research Institute of Petroleum Exploration and Development CNPCBeijing100083China Beijing Vocational College of Labour and Social Security Beijing100029China PetroChina Dagang Oilfield Exploration and Development Research Institute CNPCTianjin300280China

Knowledge about the seismic elastic modulus dispersion,and associated attenuation,in fluid-saturated rocks is essential for better interpretation of seismic observations taken as part of hydrocarbon identification and time-lapse seismic surveillance of both conventional and unconventional reservoir and overburden performances.A Seismic Elastic Moduli Module has been developed,based on the forced-oscillations method,to experimentally investigate the frequency dependence of Young's modulus and Poisson's ratio,as well as the inferred attenuation,of cylindrical samples under different confining pressure *** with three standard samples showed that the measured elastic moduli were consistent with the published data,indicating that the new apparatus can operate reliably over a wide frequency range of f∈[1-2000,10^(6)]*** Young's modulus and Poisson's ratio of the shale and the tight sandstone samples were measured under axial stress oscillations to assess the frequency-and pressure-dependent *** dry condition,both samples appear to be nearly frequency independent,with weak pressure dependence for the shale and significant pressure dependence for the *** particular,it was found that the tight sandstone with complex pore microstructure exhibited apparent dispersion and attenuation under brine or glycerin saturation conditions,the levels of which were strongly influenced by the increased effective *** addition,the measured Young's moduli results were compared with the theoretical predictions from a scaled poroelastic model with a reasonably good agreement,revealing that the combined fluid flow mechanisms at both mesoscopic and microscopic scales possibly responsible for the measured dispersion.

关键词： Low-frequency measurements Dispersion and attenuation Rock physics Fluid flow

Megafossils of Betulaceae from the Oligocene of Qaidam Basin and their paleoenvironmental and phytogeographic implications

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Plant Diversity 2024年第1期46卷 101-115页

作者： Tao Yang Jia-Hao Cai Yan-Zhi Dai hong-Yu Chen Lei Han Li Zhang Wei-Yu Liang Xu-Jun Li Wen-Jia Li Jing-Yu Wu san-Ping Xie De-Fei Yan School of Earth Sciences and Key Laboratory of Mineral Resources in Western China(Gansu Province) Lanzhou UniversityLanzhou 730000China Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008China Center for Research and Education on Biological Evolution and Environments School of Earth Sciences and EngineeringNanjing UniversityNanjing 210023China

Understanding the paleoenvironment and phytogeographical history of the Tibetan Plateau,China relies on discovering new plant *** Qaidam Basin has long been regarded as an ideal‘field laboratory’to investigate the paleoclimate and paleobiological evolution of the northern Tibetan ***,fossil angiosperms from the Qaidam Basin are rare,and our knowledge of its paleovegetation is ***,we report fossil leaves and fruits of Betulaceae found from the Oligocene Shangganchaigou Formation of northwestern Qaidam Basin(Huatugou area).Comparative morphological analysis led us to assign the fruits to the Betula subgenus Betula and the leaves to Carpinus *** findings,together with other reported fossil plants from the same locality,reveal a close floristic linkage between the Qaidam Basin and Europe during the *** northern pathway of this floristic exchange may have crossed through the Qaidam Basin during the late *** floristic linkage may have been facilitated by the continuous narrowing of the Turgai Strait and stronger westerlies,which transported moisture and provided favorable climatic ***,fossil plants collected from the Qaidam Basin suggest that during the Oligocene this region had warm and humid deciduous broad-leaf forest,which differs from the region’s modern vegetation and indicates that the Qaidam Basin may have been a suitable region for these plants to flourish and spread during the Oligocene.

关键词： Paleoenvironment Biogeography Betulaceous fossil Qaidam basin Tibetan Plateau Oligocene

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基于因子分析的板带热轧产品质量缺陷诊断

东北大学学报（自然科学版） 2022年第6期43卷 809-814页

作者：彭文辛洪伞李旭东孙杰东北大学轧制技术及连轧自动化国家重点实验室辽宁沈阳110819 东北大学低碳钢铁前沿技术研究院辽宁沈阳110819 首钢集团有限公司技术研究院北京100043

板带热轧生产过程中,产品质量影响因素与质量指标间的关系不明确,影响产品质量缺陷追溯和后续产品质量提升.将因子分析(factor analysis,FA)方法引入热轧产品质量诊断过程中,并以穿带过程宽度质量缺陷为例,采用GT;统计量对生产过程进行... 详细信息

板带热轧生产过程中,产品质量影响因素与质量指标间的关系不明确,影响产品质量缺陷追溯和后续产品质量提升.将因子分析(factor analysis,FA)方法引入热轧产品质量诊断过程中,并以穿带过程宽度质量缺陷为例,采用GT;统计量对生产过程进行监控,通过因子得分表征各生产因素对产品宽度质量指标的影响程度,得到了各因素对产品宽度缺陷的贡献率,最终实现了轧件宽度缺陷的原因定位.实际应用结果表明,以因子分析的诊断结果为基础对关键参数进行修正,能有效提升后续产品的宽度控制精度,为生产过程的稳定性和产品质量的提高提供了保证.

关键词：板带热轧因子分析质量缺陷质量诊断溯源分析

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A quantum chemical study on the mechanism of the consecutive addition of HCN to propionitrile

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Chinese Journal of Chemistry 1994年第6期12卷 490-494页

作者： hong, san-Guo WANG, Sheng Department of Chemistry, Jiangxi Normal University, Nanchang, Jiangxi 330027, China Department of Chemistry Jiangxi Normal University Nanchang Jiangxi 330027 China

MINDO/3 MO method has been used to study the mechanism of the consecutive addition of HCN to propionitrile. The results obtained for the first five steps show that the reaction is exothermic, and step 1 is the rate de... 详细信息

关键词： MINDO/3 method transition state the intrinsic reaction coordinate(IRC).

Comparison of Body Mass Index with Body Fat Percentage in the Evaluation of Obesity in Chinese

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Biomedical and Environmental Sciences 2010年第3期23卷 173-179页

作者： CHEN WANG Xu-hong HOU MING-LIANG ZHANG Yu-QIAN BAO Yu-HUA ZOU WEN-hong Zhong KUN-san XIANG WEI-PING JIA Department of Endocrinology and Metabolism Shanghai Jiao Tong University Affiliated Sixth People's Hospital Shanghai Diabetes Institute Shanghai Clinical Center for Diabetes Shanghai 200233 China Caoyang Health Center Shanghai 200062 China CHuayang Health Center Shanghai 200442 China

Objective To evaluate the present Chinese body mass index （BMI） criteria with body fat percentage （BF%） in determining obesity in Chinese population. Methods A total of 4 907 subjects （age： 20-90 yrs） were enrolled in the baselirie survey of a longitudinal epidemiological study, and 2 638 of them were reevaluated in 5.5 years later. The Chinese BMI and WHO BF% were used to define obesity, respectively. Results The diagnostic agreement between the Chinese BMI and WHO BF% definitions for obesity was poor for both men （kappa： 0.210, 95% CI： 0.179-0.241） and women （kappa： 0.327, 95% CI： 0.296-0.358）. However, BMI had a good correlation with BF% both in men （r： 0.785, P〈0.01） and women （r： 0.864, P〈0.01）. The age and sex-adjusted relative risks （RR） for incidence of type 2 diabetes （T2DM） were significantly higher in subjects with intermediate BF% （BF%：20.1%-25% for men, 30.1%-35% for women）（RR： 2.35, 95% CI： 1.23-4.48） and high BF%（BF%〉25% for men and 〉35% for women）（RR： 2.89, 95% CI： 1.43-5.81）, or in subjects with high BMI （BMI≥ 28 kg/m2）（RR： 2.46, 95% CI： 1.31-4.63） when compared to those with low BF% （BF%≤20% for men ands〈30% for women） or low BMI （BMI〈24 kg/m^2） respectively. No difference in risk could be found in those with intermediate BMI （BMI： 24-27.9 kg/m^2）（RR： 1.44, 95% CI： 0.86-2.40）, as compared to those with low BMI （BMI〈24 kg/m^2）, whose BF% ranged widely from 7.8 to 50.3%. Conclusion BMI was correlated with BF%. Both BMI and BF% were associated with high risk for T2DM. However, BMI had its limitations in the interpretation of subjects with BMI between 24 and 27.9 kg/m^2.

关键词： BMI BF% Obesity