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机械设计专家系统中的知识表示和知识库结构的研究

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微电子学与计算机 1989年第9期6卷 1-8页

作者：尹立东王复车广东深圳南头科技工业园总公司电脑部西安交通大学计算机科学与工程系

本文分析了机械设计领域MDD之知识的特征,提出了集可变框架、产生式和表技术于一体的混合知识表示方法;研究了MDD之基本知识元和学习知识元.借助于知识元不仅能有效地和完整地表达MDD知识,而且还解决了具有自动进行方案评估、指出再设... 详细信息

本文分析了机械设计领域MDD之知识的特征,提出了集可变框架、产生式和表技术于一体的混合知识表示方法;研究了MDD之基本知识元和学习知识元.借助于知识元不仅能有效地和完整地表达MDD知识,而且还解决了具有自动进行方案评估、指出再设计方向和自动实施再设计能力的机械设计专家系统之知识表示.另外,本文还讨论了知识元的组织方法及相应的知识库之结构;最后给出了知识元的表现和应用实例.

关键词：机械设计专家系统知识表示

Human neural stem cell-derived extracellular vesicles protect against ischemic stroke by activating the PI3K/AKT/mTOR pathway

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Neural Regeneration Research 2025年第11期20卷 3245-3258页

作者： Jiayi Wang Mengke Zhao dong fu Meina Wang Chao Han Zhongyue Lv Liang Wang Jing Liu Stem Cell Clinical Research Center The First Affiliated Hospital of Dalian Medical UniversityDalianLiaoning ProvinceChina Dalian Innovation Institute of Stem Cell and Precision Medicine DalianLiaoning ProvinceChina Institute(College)of Integrative Medicine Dalian Medical UniversityDalianLiaoning ProvinceChina

Human neural stem cell-derived extracellular vesicles exhibit analogous functions to their parental cells,and can thus be used as substitutes for stem cells in stem cell therapy,thereby mitigating the risks of stem cell therapy and advancing the frontiers of stem cell-derived *** lays a foundation for the development of potentially potent new treatment modalities for ischemic ***,the precise mechanisms underlying the efficacy and safety of human neural stem cell-derived extracellular vesicles remain unclear,presenting challenges for clinical *** promote the translation of therapy based on human neural stem cell-derived extracellular vesicles from the bench to the bedside,we conducted a comprehensive preclinical study to evaluate the efficacy and safety of human neural stem cell-derived extracellular vesicles in the treatment of ischemic *** found that administration of human neural stem cell-derived extracellular vesicles to an ischemic stroke rat model reduced the volume of cerebral infarction and promoted functional recovery by alleviating neuronal *** human neural stem cell-derived extracellular vesicles reduced neuronal apoptosis by enhancing phosphorylation of phosphoinositide 3-kinase,mammalian target of rapamycin,and protein kinase B,and these effects were reversed by treatment with a phosphoinositide 3-kinase *** findings suggest that human neural stem cell-derived extracellular vesicles play a neuroprotective role in ischemic stroke through activation of phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin signaling ***,we showed that human neural stem cell-derived extracellular vesicles have a good in vivo safety ***,human neural stem cell-derived extracellular vesicles are a promising potential agent for the treatment of ischemic stroke.

关键词： behavior exosome extracellular vesicles ischemic stroke mammalian target of rapamycin(mTOR) middle cerebral artery occlusion neural stem cells neuronal apoptosis phosphoinositide 3-kinase(PI3K) protein kinase B(AKT)

Single-cell omics: experimental workflow, data analyses and applications

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Science China Life Sciences 2025年第1期68卷 5-102页

作者： Fengying Sun Haoyan Li dongqing Sun Shaliu fu Lei Gu Xin Shao Qinqin Wang Xin dong Bin Duan Feiyang Xing Jun Wu Minmin Xiao Fangqing Zhao Jing-dong J.Han Qi Liu Xiaohui Fan Chen Li Chenfei Wang Tieliu Shi Department of Clinical Laboratory the Affiliated Wuhu Hospital of East China Normal University (The Second People's Hospital of Wuhu City) Pharmaceutical Informatics Institute College of Pharmaceutical SciencesZhejiang University Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration (Tongji University) Ministry of EducationOrthopaedic DepartmentTongji HospitalBioinformatics DepartmentSchool of Life Sciences and TechnologyTongji University Frontier Science Center for Stem Cells School of Life Sciences and TechnologyTongji University Translational Medical Center for Stem Cell Therapy and Institute for Regenerative Medicine Shanghai East HospitalBioinformatics DepartmentSchool of Life Sciences and TechnologyTongji University Research Institute of Intelligent Computing Zhejiang Lab Shanghai Research Institute for Intelligent Autonomous Systems Center for Single-cell Omics School of Public HealthShanghai Jiao Tong University School of Medicine National Key Laboratory of Chinese Medicine Modernization Innovation Center of Yangtze River DeltaZhejiang University Center for Bioinformatics and Computational Biology Shanghai Key Laboratory of Regulatory Biologythe Institute of Biomedical Sciences and School of Life SciencesEast China Normal University Beijing Institutes of Life Science Chinese Academy of Sciences Peking-Tsinghua Center for Life Sciences Academy for Advanced Interdisciplinary StudiesCenter for Quantitative Biology (CQB)Peking University Zhejiang Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases Women's HospitalZhejiang University School of Medicine Key Laboratory of Advanced Theory and Application in Statistics and Data Science-MOE School of StatisticsEast China Normal University

Cells are the fundamental units of biological systems and exhibit unique development trajectories and molecular features. Our exploration of how the genomes orchestrate the formation and maintenance of each cell, and control the cellular phenotypes of various organismsis, is both captivating and intricate. Since the inception of the first single-cell RNA technology, technologies related to single-cell sequencing have experienced rapid advancements in recent years. These technologies have expanded horizontally to include single-cell genome, epigenome,proteome, and metabolome, while vertically, they have progressed to integrate multiple omics data and incorporate additional information such as spatial sc RNA-seq and CRISPR screening. Single-cell omics represent a groundbreaking advancement in the biomedical field,offering profound insights into the understanding of complex diseases, including cancers. Here, we comprehensively summarize recent advances in single-cell omics technologies, with a specific focus on the methodology section. This overview aims to guide researchers in selecting appropriate methods for single-cell sequencing and related data analysis.

关键词： single-cell sequencing genome epigenome proteomics metabolomics multimodal spatial transcriptomics CRISPR screening

基于遗传优化的模糊PID控制在智能除草中的应用研究

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计算机应用研究 2011年第2期28卷 591-593页

作者：赵跃华闫玮陈树人尹东富江苏大学计算机科学与通信工程学院江苏镇江212013 江苏大学现代农业装备与技术省部共建教育部重点实验室江苏镇江212013

针对当前智能除草控制系统的非线性、时滞性及喷施精度过低等问题,设计了一种基于超代遗传算法(HG-GA)优化的模糊PID控制方案。在该方案中,针对智能除草装置的特点,设计了对应的模糊PID控制器,并对控制器的各因子进行遗传优化,从而提高... 详细信息

针对当前智能除草控制系统的非线性、时滞性及喷施精度过低等问题,设计了一种基于超代遗传算法(HG-GA)优化的模糊PID控制方案。在该方案中,针对智能除草装置的特点,设计了对应的模糊PID控制器,并对控制器的各因子进行遗传优化,从而提高系统的控制效果,同时加快了优化速度。实验结果表明这是一种有效的控制策略,尤其是在处理非线性及外部干扰方面有更好的鲁棒性。

关键词：模糊PID控制器精确喷施遗传优化

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连翘基因组大小的流式细胞仪测定

时珍国医国药 2019年第3期30卷 758-760页

作者：樊慧杰柴智殷福栋黄浩楹陈乐乐山西中医药大学山西晋中030619

目的采用流式细胞术测定连翘的基因组大小。方法摘取连翘新鲜嫩叶,以大豆品种William 82为内标,用GPB裂解液提取细胞核悬液,依次经过RNase和PI处理后,上流式细胞仪检测。结果变异系数均小于5%,表明数据可信,进而分析出连翘基因组大小约... 详细信息

目的采用流式细胞术测定连翘的基因组大小。方法摘取连翘新鲜嫩叶,以大豆品种William 82为内标,用GPB裂解液提取细胞核悬液,依次经过RNase和PI处理后,上流式细胞仪检测。结果变异系数均小于5%,表明数据可信,进而分析出连翘基因组大小约为0.74Gb。结论该研究探索了流式细胞术测定连翘基因组大小的方法,同时明确了连翘的基因组大小。

关键词：连翘基因组大小流式细胞术

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热压成形零件料片多工步连续落料工艺应用

模具技术 2017年第1期 53-55页

作者：刘丽艺傅东旭陈懋剑重庆宝钢汽车钢材部件有限公司重庆401122

热成形料片多工步连续落料工艺具有排样复杂、精度要求高且出料方式多样化三大特点。指出其落料模具具有级进模特征,R型定位销定位不易折断;滚珠导向导套导向可靠性高,面积小;工作台前面侧面可单独或同时收料,实现"一出一"、"一出二"及... 详细信息

热成形料片多工步连续落料工艺具有排样复杂、精度要求高且出料方式多样化三大特点。指出其落料模具具有级进模特征,R型定位销定位不易折断;滚珠导向导套导向可靠性高,面积小;工作台前面侧面可单独或同时收料,实现"一出一"、"一出二"及"一出多"出料时顺利堆垛。依靠细节设计合理性,保障高效、稳定落料的生产。

关键词：热成形料片连续落料级进模具

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磷酸单酯偶联剂对羟基磷灰石的表面改性研究

四川大学学报（工程科学版） 2003年第4期35卷 45-48页

作者：罗庆平李晓东尹光福周大利郑昌琼杨为中四川大学材料科学与工程学院四川成都610065

通过熔化共混等工艺制备了羟基磷灰石(HA)粉末的磷酸单酯(PL)偶联剂表面改性复合物。用水的浸润高度、疏水性保持率、润湿角等手段对改性粉末的性能进行了表征,用IR图谱对复合物的结构进行了分析。对HA粉末的煅烧温度、改性粉末的偶联... 详细信息

通过熔化共混等工艺制备了羟基磷灰石(HA)粉末的磷酸单酯(PL)偶联剂表面改性复合物。用水的浸润高度、疏水性保持率、润湿角等手段对改性粉末的性能进行了表征,用IR图谱对复合物的结构进行了分析。对HA粉末的煅烧温度、改性粉末的偶联剂加量对改性效果的影响以及改性粉末的稳定性进行了研究,初步探讨了偶联剂对粉末表面改性的作用机理。结果表明PL是一种高效的表面改性偶联剂,与羟基磷灰石的反应活性高,能与羟基磷灰石形成稳固的键合。所制备的HA-PL复合物具有良好的疏水性,稳定性。用此改性HA粉末与高聚物共混,制取HA/高聚物复合材料时将可能大大改善HA与高聚物的结合性能。

关键词：磷酸单酯偶联剂表面改性复合物

Effect of Dynamic Pressure Feedback Orifice on Stability of Cartridge-Type Hydraulic Pilot-Operated Relief Valve

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Chinese Journal of Mechanical Engineering 2023年第4期36卷 227-241页

作者： Yaobao yin dong Wang Junyong fu Hong-chao Jian School of Mechanical Engineering Tongji UniversityShanghai 201804China Shanghai Aerospace Control Technology Institute Shanghai 201109China China North Vehicle research institute Beijing 100072China

Current research on pilot-operated relief valve stability is primarily conducted from the perspective of system dynamics or stability criteria,and most of the existing conclusions focus on the spool shape,damping hole size,and pulsation frequency of the ***,the essential factors pertaining to the unstable vibration of relief valves remain *** this study,the dynamic behavior of a pilot-operated relief valve is investigated using the frequency-domain *** result suggests that the dynamic pressure feedback orifice is vital to the dynamic characteristics of the valve.A large orifice has a low flow *** this case,the fluid in the main spring chamber flows freely,which is not conducive to the stability of the relief ***,a small orifice may create significant flow resistance,thus restricting fluid *** this case,the oil inside the main valve spring chamber is equivalent to a high-stiffness liquid *** main mass-spring vibration system has a natural frequency that differs significantly from the operating frequency of the relief valve,which is conducive to the stability of the relief *** agreement is obtained between the theoretical analysis and *** results indicate that designing a dynamic pressure feedback orifice of an appropriate size is beneficial to improving the stability of hydraulic pilot-operated relief *** addition,the dynamic pressure feedback orifice reduces the response speed of the relief *** study comprehensively considers the stability,rapidity,and immunity of relief valves and expands current investigations into the dynamic characteristics of relief valves from the perspective of classical control theory,thus revealing the importance of different parameters.

关键词： Pilot-operated relief valve Dynamic pressure feedback orifice Stability Rapidity Immunity

Discovery of a new family member of arsenic–vanadium polyoxometalates with high catalytic performance for one-pot coupling of CO2, epoxides and amines

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Tungsten 2025年第1期 80-87页

作者： Fang-Qian Wang yin Zhang Wei-Wei Wang Mei-Qian fu Hong-Bing Mo Wei-dong Yu Chao Liu Jun Yan College of Chemistry and Chemical Engineering Central South University Junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[N（CH3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mechanism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

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