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曲轴锻造模具Archard磨损模型系数修正及视觉验证

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锻压技术 2024年第1期49卷 202-209页

作者：李朝昆曾琦刘庆生中国机械总院集团北京机电研究所有限公司北京100083

热模锻模具在实际生产过程中由于受到交变应力的影响,受力情况复杂且服役环境相当恶劣。基于Archard磨损模型,通过典型曲轴锻造模具的有限元模拟结果与实际磨损量的对比,计算出磨损模型的磨损系数K值,从而获得适合曲轴热锻生产的修正Arc... 详细信息

热模锻模具在实际生产过程中由于受到交变应力的影响,受力情况复杂且服役环境相当恶劣。基于Archard磨损模型,通过典型曲轴锻造模具的有限元模拟结果与实际磨损量的对比,计算出磨损模型的磨损系数K值,从而获得适合曲轴热锻生产的修正Archard磨损模型;通过修正后的Archard磨损模型预测模具寿命,并基于机器视觉系统对模具的磨损失效进行判断。结果表明:K的修正值为1.425×10^(-7),与实际测量值的吻合度达91.47%,预测寿命为6351件,与实际生产情况6400件相吻合;对磨损失效模具进行了机器视觉判断,验证了机器视觉技术在锻造模具磨损检测方向的可行性。

关键词：曲轴 Archard模型磨损系数模具磨损机器视觉寿命预测

Modeling and simulation of material distribution in the sequential co-injection molding process

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Chinese Journal of Chemical Engineering 2022年第4期35卷 507-520页

作者： qingsheng liu Youqiong liu Chuntao Jiang School of Mathematics and Statistics Xinyang Normal UniversityXinyang 464000China

In co-injection molding,the properties and distribution of polymers will affect the application of *** focus of this work is to investigate the effect of molding parameters on the skin/core material distribution based on three-dimensional(3-D)flow and heat transfer model for the sequential coinjection molding process,and the flow behaviors and material distributions of skin and core melts inside a slightly complex cavity(dog-bone shaped cavity)are predicted *** governing equations of fluids in mold are solved by finite volume method and Semi-Implicit Method for Pressure Linked Equations(SIMPLE)algorithm on collocated meshes,and the domain extension technique is employed in numerical method for this cavity to assure that the numerical algorithm is implemented *** level set transport equation which is used to trace the free surfaces in co-injection molding is discretized and solved by the 5 th-order Weighted Essentially Non-Oscillatory(WENO)scheme in space and 3 rd-order Total Variation Diminishing Runger-Kutta(TVD-R-K)scheme in time *** simulations are conducted under various volume fraction of core melt,skin and core melt temperatures,skin and core melt flow *** predicted results of material distribution in length,width and thickness directions are in close agreement with the experimental results,which indicate that volume fraction of core melt,core melt temperature and core melt flow rate are principal factors that have a significant influence on material *** results demonstrate the effectiveness of the 3-D model and the corresponding numerical methods in this work,which can be used to predict the melt flow behaviors and material distribution in the process of sequential co-injection molding.

关键词： Co-injection molding Finite volume method Simulation Level set Material distribution

习近平文化思想的内涵特征、价值意蕴与践行理路

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盐城师范学院学报（人文社会科学版） 2024年第1期44卷 1-9页

作者：刘清生唐小涵江苏科技大学马克思主义学院江苏镇江212003

习近平文化思想是习近平新时代中国特色社会主义思想的重要组成部分,是一个系统完整、内涵丰富、逻辑严密、博大精深的科学理论体系,是中国共产党领导文化建设实践经验的智慧结晶,是推进中华民族伟大复兴的精神支撑。习近平文化思想赋... 详细信息

习近平文化思想是习近平新时代中国特色社会主义思想的重要组成部分,是一个系统完整、内涵丰富、逻辑严密、博大精深的科学理论体系,是中国共产党领导文化建设实践经验的智慧结晶,是推进中华民族伟大复兴的精神支撑。习近平文化思想赋予马克思主义文化思想时代意涵,提供新时代中国文化建设行动指南,贡献崭新的人类文明发展中国方案,具有广泛而又深远的时代意义和理论价值。新征程上,努力践行习近平文化思想,以“两个结合”担负起新的文化使命,以文化自信铸就社会主义文化强国,以开放包容姿态推进中华民族现代文明,不断开创新时代宣传思想文化工作新局面,为强国建设、民族复兴提供坚强的文化力量。

关键词：习近平文化思想社会主义文化文化价值文化自信文化建设

Monitoring desertification processes in Mongolian Plateau using MODIS tasseled cap transformation and TGSI time series

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Journal of Arid Land 2018年第1期10卷 12-26页

作者： liu qingsheng liu Gaohuan HUANG Chong State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100111China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China

Most remote sensing studies assess the desertification using vegetation monitoring method. But it has the insufficient precision of vegetation monitoring for the limited vegetation cover of the desertification region. Therefore, it offers an alternative approach for the desertificafon research to assess sand dune and sandy land change using remote sensing in the desertification region. In this study, the indices derived from the well-known tasseled cap transformation （TCT）, tasseled cap angle （TCA）, disturbance index （DI）, process indicator （PI）, and topsoil grain size index （TGSI） were integrated to monitor and assess the desertification at the thirteen study sites including sand dunes and sandy lands distributed in the Mongolian Plateau （MP） from 2000 to 2015. A decision tree was used to classify the desertification on a regional scale. The average overall accuracy of 2000, 2005, 2010 and 2015 desertification classification was higher than 90%. Results from this study indicated that integration of the advantages of TCA, DI and TGSI could better assess the desertification. During the last 16 years, Badain Jaran Desert, Tengger Desert, and Ulan Buh Desert showed a relative stabilization. Otindag Sandy Land and the deserts of Khar Nuur, Ereen Nuur, Tsagan Nuur, Khongoryn Els, Hobq, and Mu Us showed a slow increasing of desertification, whereas Bayan Gobi, Horqin and Hulun Buir sandy lands showed a slow decreasing of desertification. Compared with the other 11 sites, the fine sand dunes occupied the majority of the Tengger Desert, and the coarse sandy land occupied the majority of the Horqin Sandy Land. Our findings on a three or four years＇ periodical fluctuated changes in the desertification may possibly reflect changing precipitation and soil moisture in the MR Further work to link the TCA, DI, TGSI, and PI values with the desertification characteristics is recommended to set the thresholds and improve the assessment accuracy with field investigation.

关键词： desertification MODIS desert sand dune sandy land Mongolian Plateau

Effects of land use changes for ecological restoration on soil moisture on the Chinese Loess Plateau:a meta-analytical approach

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Journal of Forestry Research 2020年第2期31卷 443-452页

作者： Bowei Yu Gaohuan liu qingsheng liu State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Soil moisture is an important resource for plant growth on the arid and semi-arid Loess Plateau of China where the‘‘Grain for Green’’project was launched in 1999,but there has been no systematic evaluation of soil moisture from the effects of ecological restoration at a regional *** systematically assessed 63 published studies during 2000-2015,including 2050 observations at 68 sites on the Loess Plateau with the aim of determining soil moisture changes and the factors influencing those *** found that,after land use conversion,soil moisture decreased by 17%in the upper 100 cm soil layer and that tree plantations and shrub lands appeared to cause soil moisture depletion which became increasingly serious with soil *** decrease of soil moisture was significantly influenced by the planting species in all restoration types(tree plantations,shrub lands,and grasslands).We also found that tree plantations and grasslands converted from farmlands consumed more soil moisture than from wasteland(including bare land,abandoned land and wild grasslands).Artificial restoration led to significant soil moisture reduction,but natural restoration had little effect on soil ***,natural restoration should be an alternative restoration practice on the Loess *** results will provide helpful information for artificial afforestation and planning ecological restoration campaigns for policy makers on water-limited regions.

关键词： Soil moisture Ecological restoration Land conversion Vegetation type Artificial afforestation

ChatGPT赋能高校信息素养教育应用场景与实践研究

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农业图书情报学报 2024年第4期36卷 91-101页

作者：罗国锋刘清生江苏科技大学镇江212003

[目的/意义]随着人工智能技术的发展,以数智技术驱动高等教育创新已逐渐深入人心,ChatGPT为高等教育教学发展和教育生态重构带来了新的机遇和挑战。研究旨在将ChatGPT工具应用到高校信息素养教育教学过程中,以打造基于ChatGPT应用的高... 详细信息

[目的/意义]随着人工智能技术的发展,以数智技术驱动高等教育创新已逐渐深入人心,ChatGPT为高等教育教学发展和教育生态重构带来了新的机遇和挑战。研究旨在将ChatGPT工具应用到高校信息素养教育教学过程中,以打造基于ChatGPT应用的高校信息素养教育人机协同教学范式,推动高校信息素养教育创新改革并提升课程教学效果。为数智时代人工智能工具在高等教育领域的应用研究和高校高质量信息素养教育开展提供参考。[方法/过程]通过对国内外相关文献进行梳理,在综述ChatGPT全球教育应用现状并揭示ChatGPT教育理论的基础上,结合当前高校信息素养教育教学问题,综合分析ChatGPT在高校信息素养教育教师教学、学生学习过程中的应用场景。同时开展实践教学对比,并通过“访谈+问卷”形式调查师生的教学满意度,以检验ChatGPT教学应用效果、总结教学问题、提出教学改进策略。[结果/结论]ChatGPT能有效促进高校信息素养教育创新、提升教学效果,师生对ChatGPT的教学应用也反馈良好。ChatGPT应用能有效提升教师的教学效率、创新教学内容、优化教学过程、改善教学管理,并能赋予学生更多的学习选择权,提升学习能动性,催生高阶思维和科研创新力。同时,ChatGPT应用也会引发工具滥用、知识误导、信息安全、知识产权等诸多问题。为此,我们要辩证看待ChatGPT的教学应用,一方面要积极推广和应用ChatGPT;另一方面,也要关注ChatGPT可能引发的各类风险,并制定前瞻性的教学管理政策和准则来规范ChatGPT应用,以充分发挥ChatGPT的教育功能,进一步推动高校信息素养教育教学改革。

关键词： ChatGPT 人工智能高等教育信息素养教育 AI素养具身认知

New approach to develop a 3D non-isothermal computational framework for injection molding process based on level set method

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Chinese Journal of Chemical Engineering 2016年第7期24卷 832-842页

作者： Xin Zhuang Jie Ouyang Chuntao Jiang qingsheng liu Department of Applied Mathematics Northwestern Polytechnical University

The simulation of three-dimensional （3D） non-isothermal, non-Newtonian fluid filling process is an extremely difficult task and remains a challenging problem, which includes polymer melt flow with free surface coupled with transient heat transfer. This paper presents a full 3D non-isothermal two-phase flow model to predict the complex flow in melt filling process, where the Cross-WLF model is applied to characterize the rheological behav- ior of polymer melt. The governing equations are solved using finite volume method with SIMPLEC algorithm on collocated grids and the melt front is accurately captured by a high resolution level set method. A domain exten- sion technique is adopted to deal with the complex cavities, which greatly reduces the computational burden. To verify the validity of the developed 3D approach, the melts filling processes in two thin rectangular cavities （one of them with a cylindrical insert） are simulated. The predicted melt front interfaces are in good agreement with the experiment and commercial software prediction. For a case with a rather complex cavity, the dynamic filling process in a hemispherical shell is successfully simulated. All of the numerical results show that the developed numerical procedure can provide a reasonable orediction for injection molding process.

关键词： Injection moldingNon-isothermalFinite voIume/SIMPLEC methodDomain extension techniqueHigh resolution level set method

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论社会法的整体本位

福州大学学报（哲学社会科学版） 2024年第2期38卷 96-103,171,172页

作者：刘清生范炎鑫福州大学法学院福建福州350108

我国古代以整体为法律本位,经近代发展后转为现代以个体为法律本位。个体本位法律高扬个体权利,具有极大的历史进步意义,但是个体本位法律存在无法应对公共利益危机、社会达尔文效应,也存在无法有效规范整体权利等局限。整体本位社会法... 详细信息

我国古代以整体为法律本位,经近代发展后转为现代以个体为法律本位。个体本位法律高扬个体权利,具有极大的历史进步意义,但是个体本位法律存在无法应对公共利益危机、社会达尔文效应,也存在无法有效规范整体权利等局限。整体本位社会法肯定社会整体利益的独立性;个体基于整体成员身份共享整体权利,对整体利益享有管理和维护权;整体是独立的有机体,整体对个体负有生存维护义务,个体对整体的存在、发展负有社会义务;如此,整体本位法律与个体本位法律得以实现优势互补。

关键词：社会法整体本位个体本位社会利益

Remote Sensing Monitoring of Surface Characteristics in the Badain Jaran, Tengger, and Ulan Buh Deserts of China

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Chinese Geographical Science 2019年第1期29卷 151-165页

作者： liu qingsheng liu Gaohuan HUANG Chong LI He State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application

Deserts and sandy land in northern China are very susceptible to sandy desertification and are the main source of sand-dust storms of Asian dust. However, because of the complex factors involved, descriptions of the relationship between sandy desertification and surface characteristics in these regions are lacking. We monitored the surface characteristics and their changes in time using information about soil, vegetation, and landforms in the Badain Jaran Desert(BJD), Tengger Desert(TD), and Ulan Buh Desert(UBD) in the northern China. The monitoring was done using tasseled cap angle(TCA), disturbance index(DI), and topsoil grain size index(TGSI) from Moderate Resolution Imaging Spectroradiometer(MODIS) images combined with a decision tree classification. Results showed that the TD had higher topsoil fine sand content, and the ratio of non-vegetated to vegetated areas was similar with that in the UBD. Northeast-southwest coarse sand dunes with thin interdune(NECTI) dominated the BD, fine sand dunes(FSD) dominated the TD, and a combination of northeast-southwest coarse sand dunes with wide interdune(NECWI) and northwest-southeast coarse sand dunes with wide interdune(NWCWI) dominated the UBD. From 2000 to 2015, in the BJD the area of the NECTI, non-sand dune(Non) and potential sand sources(PSS) increased, whereas the area of the NECWI, FSD and NWCWI decreased, indicating a improve process in the BJD. In the TD, the area covered by Non increased, whereas the area covered by PSS, NECWI, NECTI, FSD, and NWCWI decreased from 2000 to 2015. The area covered by the various surface characteristic types fluctuated annually in the UBD from 2000 to 2015. Changes in surface characteristics reflect the combined effects of natural conditions and human activity. The findings of our study will assist scientists and policy makers in proposing different management techniques to combat sandy desertification for the different surface characteristics of these regions.

关键词： surface characteristics MODIS desert tasseled cap angle disturbance index topsoil grain size index