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基于拓扑优化技术的压力机机身结构优化设计

机械设计与制造工程 2024年第8期53卷 5-9页

作者：张号高媛钱峰李相源姚伟佳大连理工大学机械工程学院辽宁大连116024

构造传动机构动态静力学模型,获取机身拓扑优化设计复杂载荷边界条件,结合带权重的折衷规划法定义机身多工况刚度优化模型。设定优化前后优化区域的体积比为约束条件,基于层次分析法决策矩阵确定权重因子,以静态刚度最大为优化目标进行... 详细信息

构造传动机构动态静力学模型,获取机身拓扑优化设计复杂载荷边界条件,结合带权重的折衷规划法定义机身多工况刚度优化模型。设定优化前后优化区域的体积比为约束条件,基于层次分析法决策矩阵确定权重因子,以静态刚度最大为优化目标进行机身多工况刚度拓扑优化。以优化结果材料密度云图为依据确定最优材料分布,结合结构工艺性设计压力机机身结构方案,实现机身结构性能轻量化设计,可为突破传统经验设计方法、探索现代结构设计技术提供理论依据。

关键词：压力机动态静力学层次分析法多工况拓扑优化

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过表达miRNA-424-5p靶向AKT3对奶牛子宫内膜上皮细胞凋亡的影响

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中国畜牧兽医 2024年第8期51卷 3635-3642页

作者：姚伟佳罗春海刘佳金王薇李丹阳刘炳琦付世新黑龙江八一农垦大学动物科技学院大庆163319

[目的]本试验通过过表达miRNA-424-5p,明确miRNA-424-5p与其靶基因丝氨酸/苏氨酸激酶3(AKT serine/threonine kinase 3,AKT3)对奶牛子宫内膜上皮细胞凋亡影响的机制,为阐明miRNA-424-5p在奶牛胎盘分离过程中的作用机制提供试验基础和理... 详细信息

[目的]本试验通过过表达miRNA-424-5p,明确miRNA-424-5p与其靶基因丝氨酸/苏氨酸激酶3(AKT serine/threonine kinase 3,AKT3)对奶牛子宫内膜上皮细胞凋亡影响的机制,为阐明miRNA-424-5p在奶牛胎盘分离过程中的作用机制提供试验基础和理论依据。[方法]试验分为3组:空白对照组(Control)、阴性对照组(miRNA-424-5p mimics NC)和过表达组(miRNA-424-5p mimics)。采用茎环法实时荧光定量PCR检测转染miRNA-424-5p mimics后奶牛子宫内膜上皮细胞miRNA-424-5p的表达变化;采用Western blotting及实时荧光定量PCR检测过表达后AKT3和凋亡相关因子的表达变化,采用Annexin V-FITC/PI法检测奶牛子宫内膜上皮细胞凋亡情况。[结果]与空白对照及阴性对照组相比,转染miRNA-424-5p mimics后子宫内膜上皮细胞miRNA-424-5p mRNA的表达量极显著升高(P<0.01),B淋巴细胞瘤-2(B-cell lymphoma-2,Bcl-2)相关X蛋白(Bax)、半胱氨酸天冬氨酸蛋白酶3(cysteinyl aspartate specific proteinase 3,Caspase3)和Caspase9的mRNA表达量极显著升高(P<0.01),AKT3和Bcl-2的mRNA表达量极显著降低(P<0.01);Bax和Caspase3蛋白表达量极显著升高(P<0.01),Caspase9蛋白表达量显著升高(P<0.05),AKT3和Bcl-2蛋白表达量极显著降低(P<0.01);细胞凋亡率极显著升高(P<0.01)。[结论]过表达miRNA-424-5p可通过靶向调控AKT3使奶牛子宫内膜上皮细胞凋亡因子Bax、Caspase3和Caspase9的表达量增加,使Bcl-2的表达量降低,进而促进细胞凋亡。

关键词：奶牛 miRNA-424-5p AKT3 子宫内膜上皮细胞凋亡

Distributed Encirclement Control with Arbitrary Spacing for Multiple Anonymous Mobile Robots

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Distributed Encirclement Control with Arbitrary Spacing for ...

胎衣不下奶牛miRNA-185靶向调控血管内皮生长因子A表达的研究

第36届中国控制会议

作者： weijia yao Zhiwen Zeng Xiangke Wang Huimin Lu Zhiqiang Zheng College of Mechatronics and Automation National University of Defense Technology

ISBN: (纸本)9781538629185

Encirclement control enables a multi-robot system to rotate around a target while they still preserve a circle formation,which is useful in real world applications such as entrapping a hostile *** this paper,a distributed control law is proposed for any number of anonymous and oblivious robots in random three dimensional positions to form a specified circular formation with any desired inter-robot angular distances(***) and encircle around the *** spacing is useful for a system composed of heterogeneous robots which,for example,possess different kinematics capabilities,since the spacing can be designed manually for any specific *** robots are modelled by single-integrator models,and they can only sense the angular positions of their two neighbouring robots,so the control law is *** analysis and simulation results are provided to prove the stability and effectiveness of the proposed control strategy.

关键词： encirclement distributed control multi-robot system arbitrary spacing heterogeneous robots

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中国畜牧兽医 2024年第3期51卷 916-925页

作者：罗春海郑程远张梦龙姚伟佳刘佳金刘炳琦王薇付世新黑龙江八一农垦大学动物科技学院大庆163319 齐齐哈尔大学食品与生物工程学院齐齐哈尔161000

【目的】通过体内和体外试验检测miRNA-185及血管内皮生长因子A(vascular endothelial growth factor A,VEGFA)在胎衣正常排出和胎衣不下(RFM)奶牛胎盘组织中的差异表达情况及VEGFA在奶牛母体胎盘组织中表达分布,验证及明确miRNA-185和V... 详细信息

【目的】通过体内和体外试验检测miRNA-185及血管内皮生长因子A(vascular endothelial growth factor A,VEGFA)在胎衣正常排出和胎衣不下(RFM)奶牛胎盘组织中的差异表达情况及VEGFA在奶牛母体胎盘组织中表达分布,验证及明确miRNA-185和VEGFA与奶牛胎衣不下发生密切相关并存在靶向调节关系,为深入研究miRNA-185在奶牛胎衣不下发生过程中的作用提供理论依据和试验基础。【方法】采用实时荧光定量PCR法检测胎衣正常排出及胎衣不下奶牛母体胎盘组织中miRNA-185及VEGFA基因表达情况,采用荧光原位杂交技术(FISH)检测VEGFA在母体胎盘组织的表达分布及mRNA的差异表达情况;采用双荧光素酶明确miRNA-185与VEGFA的靶向调节关系,采用实时荧光定量PCR及Western blotting检测体外转染miRNA185 mimics、miRNA-185 inhibitor及miRNA-185 NC后VEGFA mRNA及蛋白的差异表达情况。【结果】实时荧光定量PCR结果显示,与胎衣正常排出奶牛相比,胎衣不下奶牛体内miRNA-185及VEGFA的表达水平均极显著下调(P<0.01);荧光原位杂交结果显示,VEGFA mRNA主要在奶牛子宫内膜上皮细胞中表达。VEGFA是miRNA-185的靶向调节蛋白。与阴性对照组相比,转染miRNA-185 mimics后VEGFA的mRNA及蛋白表达水平均极显著下调(P<0.01),转染miRNA-185 inhibitor后VEGFA的mRNA及蛋白表达水平均极显著上调(P<0.01)。【结论】胎衣不下奶牛母体胎盘组织内miRNA-185及VEGFA表达显著降低,VRGFA主要在子宫内膜上皮细胞中表达,miRNA-185可通过靶向调控VEGFA的表达参与奶牛胎衣不下的发生发展。

关键词：奶牛胎衣不下 miRNA-185 血管内皮生长因子A 母体胎盘

Enhancing crystal integrity and structural rigidity of CsPbBr_(3) nanoplatelets to achieve a narrow colorsaturated blue emission

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Light(Science & Applications) 2024年第5期13卷 985-997页

作者： Qianqian Huang Wenxu Yin Bo Gao Qingsen Zeng Dong yao Hao Zhang Yinghe Zhao weijia Zheng Jiaqi Zhang Xuyong Yang Xiaoyu Zhang Andrey L.Rogach Key Laboratory of Automobile Materials MOE School of Materials Science&Engineeringand Jilin Provincial International Cooperation Key Laboratory of High-Efficiency Clean Energy MaterialsJilin UniversityChangchunChina. State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchunChina. State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhanHubeiChina. Department of Chemistry University of VictoriaVictoriaBCCanada. Key Laboratory of Advanced Display and System Applications of Ministry of Education Shanghai UniversityShanghaiChina. Department of Materials Science and Engineering and Centre for Functional Photonics(CFP)City University of Hong KongHong Kong S.A.RChina

Quantum-confined CsPbBr_(3) perovskites are promising blue emitters for ultra-high-definition displays,but their soft lattice caused by highly ionic nature has a limited ***,we endow CsPbBr_(3) nanoplatelets(NPLs)with atomic crystal-like structural rigidity through proper surface engineering,by using strongly bound N-dodecylbenzene sulfonic acid(DBSA).A stable,rigid crystal structure,as well as uniform,orderly-arranged surface of these NPLs is achieved by optimizing intermediate reaction stage,by switching from molecular clusters to mono-octahedra,while interaction with DBSA resulted in formation of a Cs_(x)O monolayer shell capping the NPL *** a result,both structural and optical stability of the CsPbBr3 NPLs is enhanced by strong covalent bonding of DBSA,which inhibits undesired phase transitions and decomposition of the perovskite phase potentially caused by ligand ***,rather small amount of DBSA ligands at the NPL surface results in a short inter-NPL spacing in their closely-packed films,which facilitates efficient charge injection and *** photoluminescence of the produced CsPbBr_(3) NPLs is bright(nearly unity emission quantum yield)and peaks at 457 nm with an extremely narrow bandwidth of 3.7 nm at 80 K,while the bandwidth of the electroluminescence(peaked at 460 nm)also reaches a record-narrow value of 15 nm at room *** value corresponds to the CIE coordinates of(0.141,0.062),which meets Rec.2020 standards for ultra-high-definition displays.

关键词： temperature stability narrow

Cooperative Encirclement Control for a Group of Targets by Decentralized Robots with Collision Avoidance

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Cooperative Encirclement Control for a Group of Targets by D...

叉车阀检测台项目中利用数据库技术实现组态王数据保存及与VB数据交换的方案

第37届中国控制会议

作者： Junchong Ma weijia yao Wei Dai Huimin Lu Junhao Xiao Zhiqiang Zheng Department of Automation National University of Defense Technology

This study focuses on multi-target capture and encirclement control problem for multiple mobile robots. With the distributed architecture, this problem involves a group of robots to encircle several moving targets in a coordinated circle formation. In order to efficiently allocate the targets to robots, a Hybrid Dynamic Task Allocation（HDTA） algorithm was proposed, in which a temporary "manager" robot was assigned to negotiate with other robots. For encirclement formation, a robust control law was introduced for any number of mobile robots to form a specific circle formation with arbitrary inter-robot angular spacing. In view of safety, an online collision avoidance algorithm combining the sub-targets and Artificial Potential Fields（APF） approaches was proposed,which ensures that the paths of robots are collision-free. To prove the validity and robustness of the proposed scheme, both theoretical analysis and simulation experiments were conducted.

关键词： Multi-robot Multi-target Encirclement Control Task Allocation Collision Avoidance

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机床与液压 2015年第4期43卷 144-146页

作者：刘俊姚伟嘉合肥工业大学机械与汽车工程学院安徽合肥230009

在叉车控制阀检测实验台的检测程序设计过程中,在运行用组态王编写的检测程序时,需要把更改的合格判定校核参数数值保存以便下次使用。利用数据库建立表格文件,把更改的变量数值存放在数据库表格当中,可以实现组态王数据存储;每次检测... 详细信息

在叉车控制阀检测实验台的检测程序设计过程中,在运行用组态王编写的检测程序时,需要把更改的合格判定校核参数数值保存以便下次使用。利用数据库建立表格文件,把更改的变量数值存放在数据库表格当中,可以实现组态王数据存储;每次检测时组态王程序会和VB程序进行检测油压数据交换,不同型号阀由不同的组态王检测主程序执行,把要交换的数据存放在同一个数据库表格中,每一个组态王检测主程序都可以通过访问相同的数据库表格和VB程序进行数据交换。

关键词：数据库组态王 VB 数据存储数据交换

非线性数据分析方法在基因芯片进行疾病诊断中的应用

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计算机与应用化学 2006年第3期23卷 214-218页

作者：姚微佳李通化同济大学化学系上海200092

随着人类基因组计划研究的深入,基因芯片技术应运而生,由此为生物医学领域的研究工作带来了新的契机。借助基因芯片技术,成功地对不同类别的癌症正确分类,对于癌症的早期诊断和及时治疗都有重要意义。针对芯片数据少样本多变量的特点,... 详细信息

随着人类基因组计划研究的深入,基因芯片技术应运而生,由此为生物医学领域的研究工作带来了新的契机。借助基因芯片技术,成功地对不同类别的癌症正确分类,对于癌症的早期诊断和及时治疗都有重要意义。针对芯片数据少样本多变量的特点,本文创新性地将非线性数据分析方法核映射应用于急性白血病基因芯片数据挖掘工作中,通过构筑核矩阵,在不进行变量选择的前提下,有效地将数据维数大幅度降低,同时利用自组织映射算法,成功地将两类白血病完全分开。此外与使用F-检验进行基因选择的方法进行了比较,最后利用方差分析对数据集的差异性进行了讨论。

关键词：基因芯片白组织映射核映射 F-检验方差分析

Reinforcement learning based adaptive control for uncertain mechanical systems with asymptotic tracking

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Defence Technology（防务技术） 2024年第4期34卷 19-28页

作者： Xiang-long Liang Zhi-kai yao yao-wen Ge Jian-yong yao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China College of Automation&College of Artificial Intelligence Nanjing University of Post and TelecommunicationNanjing210023China

This paper mainly focuses on the development of a learning-based controller for a class of uncertain mechanical systems modeled by the Euler-Lagrange *** considered system can depict the behavior of a large class of engineering systems,such as vehicular systems,robot manipulators and *** these systems are often characterized by highly nonlinear characteristics,heavy modeling uncertainties and unknown perturbations,therefore,accurate-model-based nonlinear control approaches become *** by the challenge,a reinforcement learning(RL)adaptive control methodology based on the actor-critic framework is investigated to compensate the uncertain mechanical *** approximation inaccuracies caused by RL and the exogenous unknown disturbances are circumvented via a continuous robust integral of the sign of the error(RISE)control *** from a classical RISE control law,a tanh(·)function is utilized instead of a sign(·)function to acquire a more smooth control *** developed controller requires very little prior knowledge of the dynamic model,is robust to unknown dynamics and exogenous disturbances,and can achieve asymptotic output ***,co-simulations through ADAMS and MATLAB/Simulink on a three degrees-of-freedom(3-DOF)manipulator and experiments on a real-time electromechanical servo system are performed to verify the performance of the proposed approach.

关键词： Adaptive control Reinforcement learning Uncertain mechanical systems Asymptotic tracking