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基于达索3DE的选煤厂非标件参数化设计

煤矿机械 2024年第3期45卷 194-196页

作者：付宇别铜选郑伟生中煤西安设计工程有限责任公司西安710054

为解决选煤厂非标件使用三维装配式设计中设计效率低、修改不易等问题,在大海则选煤厂BIM正向设计中对非标件协同设计流程进行了研究。基于达索3DE平台KAC模块的流程化定制功能,建立选煤厂非标件溜槽三维模型,快速导出材料报表,完成溜... 详细信息

为解决选煤厂非标件使用三维装配式设计中设计效率低、修改不易等问题,在大海则选煤厂BIM正向设计中对非标件协同设计流程进行了研究。基于达索3DE平台KAC模块的流程化定制功能,建立选煤厂非标件溜槽三维模型,快速导出材料报表,完成溜槽二维出图。将此方法推广到选煤厂其他非标件三维建模中,不仅减少设计返工,而且显著提升选煤厂非标件的设计效率,具有推广价值。

关键词：非标件参数化设计达索3DE 溜槽

硬脆材料微磨削延性域复合临界条件建模及试验研究

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机械工程学报 2013年第23期49卷 191-198页

作者：程军巩亚东阎旭强郑伟生东北大学机械工程与自动化学院沈阳110004

分析硬脆材料微磨削表面形成机理并建立了微磨削槽磨未变形切屑厚度hm数学模型,引入微尺度效应系数Md、延性域系数与延-脆性域系数ζ0与ζ1,针对硬脆材料特性提出微磨削延性域,延-脆性域复合临界条件模型。基于精密微磨削机床进行钠钙... 详细信息

分析硬脆材料微磨削表面形成机理并建立了微磨削槽磨未变形切屑厚度hm数学模型,引入微尺度效应系数Md、延性域系数与延-脆性域系数ζ0与ζ1,针对硬脆材料特性提出微磨削延性域,延-脆性域复合临界条件模型。基于精密微磨削机床进行钠钙玻璃与单晶硅这两种典型材料的微尺度槽磨磨削试验,通过对试验结果分析得出两种材料微磨削表面裂纹变化规律。基于实际试验数据结果对提出的硬脆材料微磨削复合临界条件模型进行验证,证明了所提出模型的科学性。分别给出钠钙玻璃与单晶硅的延性域与延-脆性域微磨削加工参数a0与a1,为硬脆材料微磨削延性域临界磨削条件研究提供了理论参考与试验依据。

关键词：微磨削硬脆材料延性域复合临界条件

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功能延拓与价值重构:网络新闻跟帖演进研究

江西师范大学学报（哲学社会科学版） 2019年第3期52卷 115-121页

作者：熊茵项国雄郑为升江西师范大学新闻与传播学院

曾是新闻“衍生品”的跟帖至今已成为重要的互联网内容产品和蔚为壮观的媒介文化景观。这一现实与网络新闻跟帖在功能和价值上双重进阶发展密不可分。采用问卷调查和访谈等手段,对网民在跟帖阅读中“满足实得”开展探索性的实证研究。... 详细信息

曾是新闻“衍生品”的跟帖至今已成为重要的互联网内容产品和蔚为壮观的媒介文化景观。这一现实与网络新闻跟帖在功能和价值上双重进阶发展密不可分。采用问卷调查和访谈等手段,对网民在跟帖阅读中“满足实得”开展探索性的实证研究。研究发现,跟帖满足了网民在事实、知识、情绪、社交等多方面需求,跟帖的传播功能得以多维度延拓,实现了超越“碎片化”的价值重构,也对专业新闻“元叙事”带来巨大冲击和解构。

关键词：网络新闻跟帖传播功能价值满足实得

Plate tectonics in the Archean:Observations versus interpretations

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Science China Earth Sciences 2024年第1期67卷 1-30页

作者： YongFei zheng School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Key Laboratory of Crust-Mantle Materials and Environment Chinese Academy of SciencesHefei 230026China Center of Excellence for Comparative Planetology Chinese Academy of SciencesHefei 230026China

Plate tectonics theory,established in the 1960s,has been successful in explaining many geological phenomena,processes and events that occurred in the ***,the theory has often struggled to provide a coherent framework in interpreting geological records in continental interior and Precambrian *** dealing with the relationship between plate tectonics and continental geology,continental interior tectonics was often separated from continental margin tectonics in the inheritance and development of their structure and *** separation led to the illusion that the plate tectonics theory is not applicable to Precambrian geology,particularly in explaining the fundamental geological characteristics of Archean *** this illusion does not mean that the Archean continental crust did not originate from a regime of plate tectonics,it led to the development of alternative tectonic models,often involving vertical movements under a regime of stagnant lid tectonics,including not only endogenous processes such as gravitational sagduction,mantle plumes and heat pipes but also exogenous processes such as bolide *** vertical processes were not unique to the Archean but persisted into the *** result from mantle poloidal convection at different depths,not specific to any particular *** the plate tectonics theory from the traditional kinematic model in the 20th century to a holistic kinematic-dynamic model in the 21st century and systematically examining the vertical transport of matter and energy at plate margins,it is evident that plate tectonics can explain the common geological characteristics of Archean cratons,such as lithological associations,structural patterns and metamorphic *** deciphering the structure and composition of convergent plate margins as well as their dynamics,the formation and evolution of continental crust since the Archean can be divided into ancient plate tectonics in the Preca

关键词： Plate tectonics Archean geology Continental origin Crustal reworking Plate interior Plate margin

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论司马相如《封禅文》文体归属的变迁

中北大学学报（社会科学版） 2018年第4期34卷 52-57页

作者：郑伟生中山大学中文系广东广州510275

历代文人对司马相如《封禅文》文体归属的认识主要有封禅体、符命体、辞赋或颂赞体三种情况。刘勰注重封禅礼制与"立言不朽"观念,故《文心雕龙》将之归于封禅体;萧统关注魏晋南北朝兴盛的符命文化,《文选》将之归于符命体;姚鼐、曾国藩... 详细信息

历代文人对司马相如《封禅文》文体归属的认识主要有封禅体、符命体、辞赋或颂赞体三种情况。刘勰注重封禅礼制与"立言不朽"观念,故《文心雕龙》将之归于封禅体;萧统关注魏晋南北朝兴盛的符命文化,《文选》将之归于符命体;姚鼐、曾国藩等人将其归属辞赋或颂赞体,这与清代文体分类思想的发展有关。对《封禅文》文体归属不同观点及其成因的探析,既有文体学意义,也有政治文化意义。

关键词：司马相如《封禅文》封禅礼制符命文化文体归属

Discovery of the Significant Impacts of Swell Propagation on Global Wave Climate Change

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Journal of Ocean University of China 2024年第3期23卷 594-604页

作者： zheng Chongwei Dalian Naval Academy Dalian 116018China Marine Resources and Environment Research Group on the Maritime Silk Road Dalian 116018China

This study compared the differences in the wave climate in the South China Sea and North Indian Ocean under these two datasets:ERA-40 wave reanalysis and Mei’s hindcast wave *** the numerical calculation of regional ocean waves,the wave climate characteristics exhibited significant bias if the influence of external swells(swells from afar)was not fully considered,which may provide an incorrect basis for global climate change analysis.1)The trends of the significant wave height(SWH)obtained from the two datasets showed significant differences,such as those of the Bay of Bengal and the Java Sea in *** the past 45 years,SWH from ERA-40(SWH-ERA)exhibited a significant annual increase in low-latitude waters of the North Indian Ocean(0.2-0.6 cm yr^(-1))and South China Sea(0.2-0.8 cm yr^(-1)).2)In the Bay of Bengal,the SWH-ERA in each month was generally 0.5 m higher than the SWH from Mei’s hindcast wave data(SWH-Mei)and can reach 1.0 m higher in some months.3)In the Bay of Bengal,SWH-ERA and SWH-Mei increased significantly at annual rates of 0.13 and 0.27 cm yr^(-1),*** increasing trend was mainly reflected after ***-ERA showed a trough in 1975(1.33 m)and a crest in 1992(1.83 m),which were not reflected in SWH-Mei.

关键词： wave climate climatic trend monthly variation annual variation external swell

A positive trend in the stability of global offshore wind energy

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Acta Oceanologica Sinica 2024年第1期43卷 123-134页

作者： Chongwei zheng Dalian Naval Academy Dalian 116018China Marine Resources and Environment Research Group on the Maritime Silk Road Dalian 116018China Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100China

The recognition on the trend of wind energy stability is still extremely rare,although it is closely related to acquisition efficiency,grid connection,equipment lifetime,and costs of wind energy *** the 40-year(1979–2018)ERA-Interim data from the European Center for Medium-Range Weather Forecasts,this study presented the spatial-temporal distribution and climatic trend of the stability of global offshore wind energy as well as the abrupt phenomenon of wind energy stability in key regions over the past 40 years with the climatic analysis method and Mann-Kendall(M-K)*** results show the following 5 points.(1)According to the coefficient of variation(C_(v))of the wind power density,there are six permanent stable zones of global offshore wind energy:the southeast and northeast trade wind zones in the Indian,Pacific and Atlantic oceans,the Southern Hemisphere westerly,and a semi-permanent stable zone(North Indian Ocean).(2)There are six lowvalue zones for both seasonal variability index(S_(v))and monthly variability index(M_(v))globally,with a similar spatial distribution as that of the six permanent stable zones.M_(v) and S_(v) in the Arabian Sea are the highest in the world.(3)After C_(v),M_(v) and S_(v) are comprehensively considered,the six permanent stable zones have an obvious advantage in the stability of wind energy over other sea areas,with C_(v) below 0.8,M_(v) within 1.0,and S_(v) within 0.7 all the year round.(4)The global stability of offshore wind energy shows a positive climatic trend for the past four decades.C_(v),M_(v) and S_(v) have not changed significantly or decreased in most of the global ocean during 1979 *** is,wind energy is flat or more stable,while the monthly and seasonal variabilities tend to shrink/smooth,which is beneficial for wind energy utilization.(5)C_(v) in the low-latitude Pacific and M_(v) and S_(v) in both the North Indian Ocean and the low-latitude Pacific have an obvious abrupt phenomenon at the end of

关键词： global oceans wind energy stability spatial-temporal distribution climatic trend

Wind power and sand/dust storms

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 175-176页

作者： XiaoJing zheng Center for Particle-Laden Turbulence Lanzhou UniversityLanzhou 730000China

Sand/dust storms,a globally prevalent catastrophic weather phenomenon,can cause significant erosion to the climate and ecological *** high concentration of sand particles they carry not only impacts atmospheric qualit... 详细信息

关键词： Wind power and sand/dust storms

从东山县无障碍旅游岛建设谈无障碍环境建设设计

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江西建材 2023年第5期 418-420页

作者：郑为胜漳州市城市规划设计研究院有限公司福建漳州363000

文中主要探讨了无障碍环境建设的设计原则和技术要点,以及其在提升社会包容性和促进可持续发展方面的重要性,通过深入分析无障碍环境建设的背景和目标,提出了一些设计指导原则,并探讨了一些创新的技术和方法,以推动无障碍环境建设的进展。

关键词：无障碍环境建设设计原则技术要点社会包容性可持续发展