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Journal of Iron and Steel Research International 2024年第4期31卷 894-908页

作者： yan-li xin Zhi-ying Gao Bo Tian Qing-dong Zhang School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China

In the high-speed cold tandem rolling process of thin plate,chatter or slip instability gives rise to the deterioration of equipment and product *** instability behavior is closely related to interfacial friction-lubrication con-dition which is generally characterized by the friction ***,with higher and higher speed requirements,the commonly used model of friction coefficient is no longer applicable and accurate.A novel approach is suggested to calculate the speed-dependent friction coefficient,in which the viscosity-pressure-temperature effects of the lubricant,surface roughness states of work rolls and rolled piece are comprehensively involved and the mixed flm lubrication theory is ***,the influences of friction coefficient on the instability of slip and chatter are investigated for a five-stand cold tandem rolling *** one side,the critical friction coefficient for each stand is determined by calculating the corresponding slip factor;on the other hand,the friction coefficient varying with rolling speed is combined with the model of theoretical critical rolling speed presented under constant friction coefficient,so that the speed threshold is ***,the stable and unstable regions corresponding to the rear three stands are individually discussed,and the technical strategies are proposed to suppress both slip and chatter frequently occurring in the actual rolling process.

关键词： Cold tandem rolling:Oil film thickness Speed-dependent friction coefficient-Slip:Chatter

不同险态情景下共驾型智能车辆接管行为特征分析

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吉林大学学报（工学版） 2024年第3期54卷 683-691页

作者：严利鑫冯进培郭军华龚毅轲华东交通大学交通运输工程学院南昌330013

为提高驾驶人在不同险态交通情景下接管智能车辆的安全性,在模拟驾驶平台上分别研究了高速公路、山区道路和城市道路3类典型险态环境下驾驶人接管行为的特征和差异性。试验采集并分析了16名驾驶人在3类典型险态环境下的驾驶行为数据。... 详细信息

为提高驾驶人在不同险态交通情景下接管智能车辆的安全性,在模拟驾驶平台上分别研究了高速公路、山区道路和城市道路3类典型险态环境下驾驶人接管行为的特征和差异性。试验采集并分析了16名驾驶人在3类典型险态环境下的驾驶行为数据。结果表明:①驾驶人在接管车辆时采取的应急操作包括制动、转向、同时转向制动3种,各行为占比分别为71.4%、16.7%和11.9%。②不同险态交通情景下驾驶人接管反应时间无显著差异(P>0.05);在高速-城市险态情景下车辆最大纵向减速度存在显著差异(P=0.002<0.05),在山区-城市险态情景下车辆最大纵向减速度存在显著差异(P=0.048<0.05);在城市-山区险态情景下车辆最大转向盘转角存在显著差异(P=0.015<0.05);在山区-高速险态情景下车辆最大转向盘转角存在显著差异(P=0.000<0.05)。说明在不同险态交通情景下应采用不同的接管措施以提升接管的安全性和有效性。本文研究结果可为不同险态环境下的智能车辆接管系统研发提供参考。

关键词：交通运输系统工程智能车辆接管行为险态场景警报方式

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Distributed QoS multicast routing in networks with imprecise state information

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Journal of Systems Engineering and Electronics 2005年第4期16卷 866-874页

作者： yan xin li Layuan Dept. of Computer Science Wuhan Univ. of Technology Wuhan 430063 P.R. China

The goal of quality-of-service （QoS） multicast routing is to establish a multicast tree which satisfies certain constraints on bandwidth, delay and other metrics. The network state information maintained at every node is often im- precise in a dynamic environment because of non-negligible propagation delay of state messages, periodic updates due to overhead concern, and hierarchical state aggregation. The existing QoS multicast routing algorithms do not provide satisfactory performance with imprecise state information. We propose a distributed QoS multicast routing scheme based on traffic lights, called QMRI algorithm, which can probe multiple feasible tree branches, and select the optimal or near-optimal branch through the UR or TL mode for constructing a multicast tree with QoS guarantees if it exists. The scheme is designed to work with imprecise state information. The proposed algorithm considers not only the QoS requirements but also the cost optimality of the multicast tree. The correctness proof and the complexity analysis about the QMRI algorithm are also given. In addition, we develop NS2 so that it is able to simulate the imprecise network state information. Extensive simulations show that our algorithm achieves high call-admission ratio and low-cost multicast trees with modest message overhead.

关键词： quality-of-service muting multicast imprecise state traffic lights simulation.

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“赶考”视域下“三个务必”的时代内涵探析

山西大同大学学报（社会科学版） 2024年第4期38卷 7-11页

作者：李艳馨王怡亮太原科技大学马克思主义学院山西太原030000

习近平总书记在党的二十大提出了“三个务必”的全新论断,对“两个务必”进行了思想升华和理论深化,对“赶考”精神进行了接续发展,有其深远的科学内涵。其中,“不忘初心、牢记使命”是中国共产党必须坚守的正确立场,是“赶考”的价值遵... 详细信息

习近平总书记在党的二十大提出了“三个务必”的全新论断,对“两个务必”进行了思想升华和理论深化,对“赶考”精神进行了接续发展,有其深远的科学内涵。其中,“不忘初心、牢记使命”是中国共产党必须坚守的正确立场,是“赶考”的价值遵循;“谦虚谨慎、艰苦奋斗”体现了中国共产党的优良品质,是“赶考”的作风保障;“敢于斗争、善于斗争”彰显了中国共产党的实践品格,是“赶考”的动力支撑。这三部分既相互贯通又自成体系,为中国共产党走好新时代赶考路提供了理论指引和行动指南。

关键词： “三个务必” “赶考” 党的二十大

修正q-Szász-Kantorovich算子在紧圆盘的复逼近(q>1)

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数学杂志 2024年第3期44卷 247-258页

作者：闫丽新韩领兄内蒙古民族大学数学科学学院内蒙古通辽028000

本文给出了修正q-Szász-Kantorovich算子在复空间的定义,参照Gal S G等人在文献[10]的方法,研究了当q>1时修正q-Szász-Kantorovich算子在紧圆盘对解析函数的逼近性质,获得了Voronovskaja结果,并给出其精确估计,丰富了修正q-Szász-Kan... 详细信息

本文给出了修正q-Szász-Kantorovich算子在复空间的定义,参照Gal S G等人在文献[10]的方法,研究了当q>1时修正q-Szász-Kantorovich算子在紧圆盘对解析函数的逼近性质,获得了Voronovskaja结果,并给出其精确估计,丰富了修正q-Szász-Kantorovich算子在复空间的逼近性质.

关键词：修正q-Szász-Kantorovich算子逼近性质 Voronovskaja型结果

Influencing factors on elastic-plastic deformation of multi-layered surfaces under sliding contact

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 472-477页

作者： yan li PAN xin-xiang XU Jiu-jun CHENG Dong Institute of Materials and Technology Dalian Maritime University China Institute of Materials and Technology Dalian Maritime University China Institute of Materials and Technology Dalian Maritime University China Institute of Materials and Technology Dalian Maritime University China

Stress distribution in the gradient multi-layered surface under a sliding contact was investigated using finite element method(FEM). The main structure parameters of layered surface discussed are total layer thickness,layer number and elastic modulus ratio of layer to the substrate. A model of multi-layered surface contact with rough slider was studied. The effect of the surface structure parameters on the elastic-plastic deformation was analyzed.

关键词： gradient multi-layered surface elastic-plastic deformation surface structure parameter FEM

CliNICOPATHOLOGICAL SIGNIFICANCE OF PTEN AND CASPASE-3 EXPRESSIONS IN BREAST CANCER

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Chinese Medical Sciences Journal 2008年第2期23卷 95-102页

作者： Xue-fei yang yan xin li-li Mao The Fourth Laboratory of Cancer Institute ＆ Department of Tumor Pathology of General Surgery Institute the First Hospital of China Medical University Shenyang 110001

Objective To investigate the expressions of PTEN and Caspase-3 proteins in human breast carcinoma,and to evaluate their clinicopathological implications during the tumorigenesis and progression of breast *** The expressions of PTEN and Caspase-3 proteins in 95 cases of breast cancer and 15 cases of benign breast diseases were investigated *** between the expression of PTEN protein,Caspase-3 protein,and clinicopathological features of breast cancers were *** The loss expression rate of PTEN protein in tumor tissues was significantly higher than that in benign breast diseases(33.7% vs.0,Plinicopathological features showed that PTEN expression level was negatively correlated with TNM stage,histological grade,axillary lymph node status,recurrence,and metastasis(P0.05).In addition,the expression of PTEN protein had significantly positive correlation with the expression of Caspase-3 protein in breast cancer(P<0.01).Conclusion The combination detection of PTEN and Caspase-3 may serve as an important index to estimate the pathobiological behavior and prognosis of breast cancer.

关键词： breast cancer tumor suppressor gene PTEN Caspase-3 prognosis

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群众性水上运动高质量发展探析

体育文化导刊 2024年第9期 56-61页

作者：张毅恒毛蕾唐家晨李彦新牛小洪中国地质大学(武汉)体育学院武汉430074 武汉体育学院竞技体育学院武汉430079

运用文献资料、逻辑分析等方法,探析群众性水上运动高质量发展的价值、困境,并提出高质量发展路径。价值:拓展水上消费空间,驱动产业模式创新;加快资源要素流动,促进区域经济协调;强化公众环保意识,引领行业绿色低碳;深化国际交流合作,... 详细信息

运用文献资料、逻辑分析等方法,探析群众性水上运动高质量发展的价值、困境,并提出高质量发展路径。价值:拓展水上消费空间,驱动产业模式创新;加快资源要素流动,促进区域经济协调;强化公众环保意识,引领行业绿色低碳;深化国际交流合作,推进传统文化开放;满足群众多元需求,实现成果全民共享。困境:行业标准亟待完善;有效供给需要提升;品牌活动有待扩展;专业人才培养不足。路径:制定行业标准,推动项目持续发展;发挥特色优势,推动项目合理布局;挖掘赛事效益,打造绿水青山品牌;整合优化资源,夯实人才培养体系。

关键词：群众体育水上运动群众性高质量发展

Expression of BMP Receptors in Porcine Granulosa Cells (GCs) and Their Regulation by Luteinizing Hormone (LH)

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Agricultural Sciences in China 2011年第2期10卷 289-295页

作者： WANG Wei ZHANG Hai-yan HE Yu ZHAO Yong-yan WANG li li xin-xiu CHEN Xia XU Yin-xue College of Animal Science ＆ Technology Nanjing Agricultural UniversityNanjing 210095P.R.China

Bone morphogenetic proteins（BMPs） play critical roles in follicle growth and *** initiate signaling by assembling BMP receptors and activating Smads,which in turn alter expression of target *** mechanism underlying the regulation of the expression of BMP receptors and Smads during follicle development in pigs is still *** quantitative real-time PCR,the mRNA expression of BMP receptors and Smads in granulosa cells（GC） was *** were obtained from small porcine follicles（SF;3 mm diameter） and dominant follicles（DF;6 mm diameter）;ActR1A and BMPR2 mRNA levels in DF were significantly higher（P0.05） than that in SF,whereas BMPR1B,Smad4 and Smad7 expression tended to decrease（P0.05）.The levels of BMPR1A,ActR2,Smad1,Smad5,and Smad8 mRNA did not differ between DFs and *** investigate the effect of LH on BMP receptors in GC,cells obtained from porcine DFs were cultured in medium supplemented with different doses of luteinizing hormone（LH）.High doses of LH（4 IU mL-1） significantly decreased the concentration of estradiol（E2） and progesterone（P4） in medium and the expression of Cyp19a1（P450 aromatase,P450arom） and Cyp11a1（cholesterol side-chain cleavage enzyme P450,P450scc）,while significantly increased viable cell numbers and up-regulated expression of cyclin dependent kinase-4（CDK4） and cyclin ***,LH had no effect on the expression of BMP receptor ***,the present study indicates that the expression of members of the BMP signaling pathway in porcine GC is regulated during follicle development and the expression of BMP receptors are not regulated by LH in porcine GCs.

关键词： porcine GCs mRNA expression BMP receptors Smads LH E2 P4

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陈皮牛肉预制菜品质的研究

中国调味品 2024年第6期49卷 135-142页

作者：钱敏李焱鑫梁杰强董浩赵文红白卫东毕思远仲恺农业工程学院轻工食品学院广州510225 深圳市金阅检测科技有限责任公司广东深圳518120

预制菜是采用各种食材配以辅料,依据现代化标准加工制作而成的成品或半成品,经简易处理便可食用。将传统菜肴陈皮牛肉制作成预制菜不仅能适应当前社会发展的需要,而且能丰富现有预制菜的种类,对预制菜的长远发展具有重要意义。为探究陈... 详细信息

预制菜是采用各种食材配以辅料,依据现代化标准加工制作而成的成品或半成品,经简易处理便可食用。将传统菜肴陈皮牛肉制作成预制菜不仅能适应当前社会发展的需要,而且能丰富现有预制菜的种类,对预制菜的长远发展具有重要意义。为探究陈皮牛肉预制菜的可行性,文章通过感官评价、脂肪氧化程度、质构、挥发性风味成分等研究陈皮牛肉预制菜的不同包装方式、储存方式、货架期及品质。结果表明,陈皮牛肉预制菜在料液混合包装方式下冷冻保存3 d时感官评价最佳,脂肪氧化程度低,保持较高的食用品质,在此条件下测得其风味物质种类繁多,主要包括醛类、酯类、酮类、醇类、烯烃类等化合物,硫代巴比妥酸反应物值接近于1.0 mg/kg,预制菜的质构等品质接近于传统陈皮牛肉菜肴。

关键词：陈皮牛肉预制菜感官品质货架期