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O2O外卖价格促销策略对消费者购买意愿的影响研究

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中国管理科学 2024年第2期32卷 254-264页

作者：钟琦曲冠桥唐加福东北财经大学管理科学与工程学院辽宁大连116025 国际商业机器全球服务(大连)有限公司辽宁大连116044

O2O外卖行业如何通过差异化促销策略提升用户体验、提高购买意愿,是O2O外卖平台和餐饮商家十分关注的问题。O2O外卖常见的价格促销方式有13种,本文将其梳理归纳为三类促销策略:优惠券类、折扣类和附加服务费优惠类。基于刺激-机体-反应... 详细信息

O2O外卖行业如何通过差异化促销策略提升用户体验、提高购买意愿,是O2O外卖平台和餐饮商家十分关注的问题。O2O外卖常见的价格促销方式有13种,本文将其梳理归纳为三类促销策略:优惠券类、折扣类和附加服务费优惠类。基于刺激-机体-反应模型(SOR模型),引入感知促销价值因素,建立O2O外卖价格促销策略对消费者购买意愿影响机制的理论模型;通过问卷星在线收集567份样本数据并进行结构方程模型分析,针对不同价格促销策略对潜在消费者购买意愿的影响路径和作用机制进行实证检验,并验证感知促销利益和感知促销成本的中介效应。研究结果表明,在三类价格促销策略中,优惠券类促销策略对潜在消费者购买意愿的影响最大;附加服务费优惠类促销策略对于O2O外卖消费者的购买意愿影响不大;与优惠券类促销策略直接促使消费者做出购买决策不同,折扣类促销策略下消费者需要对感知促销成本和感知促销利益进行权衡后做出最终购买决策。研究结论为O2O外卖平台和餐饮商家改进现有促销策略提供理论依据和参考。

关键词： O2O外卖价格促销策略 SOR模型购买意愿

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反向式行星滚柱丝杠副的螺纹牙修形设计

机械传动 2024年第4期48卷 109-115页

作者：乔冠郝志鹏廖荣张楠刘更内蒙古工业大学内蒙古自治区先进制造技术重点实验室内蒙古呼和浩特010051 西北工业大学陕西省机电传动与控制工程实验室陕西西安710072

基于反向式行星滚柱丝杠副(Inverted Planetary Roller Screw Mechanism,IPRSM)的螺纹牙载荷分布情况,分析了滚柱修形和丝杠修形对其载荷分布的影响。结果表明,丝杠-滚柱接触侧的载荷不均程度比长螺母-滚柱接触侧严重,对滚柱修形后,最... 详细信息

基于反向式行星滚柱丝杠副(Inverted Planetary Roller Screw Mechanism,IPRSM)的螺纹牙载荷分布情况,分析了滚柱修形和丝杠修形对其载荷分布的影响。结果表明,丝杠-滚柱接触侧的载荷不均程度比长螺母-滚柱接触侧严重,对滚柱修形后,最大接触应力以及最大载荷得到了有效降低,螺纹牙上的载荷分布更加均匀;而长螺母-滚柱接触侧对修形量变化较丝杠-滚柱接触侧更加敏感。同样,丝杠修形可有效降低最大载荷。研究对优化IPRSM的载荷分布具有一定的参考意义。

关键词：反向式行星滚柱丝杠副螺纹牙修形载荷分布有限元分析

同方期刊数据库博看期刊评论

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加工中心主轴关键热敏感点选取与热误差预测

组合机床与自动化加工技术 2024年第2期 169-174,181页

作者：田春苗季泽平郭世杰唐术锋乔冠内蒙古工业大学机械工程学院呼和浩特010051 内蒙古工业大学内蒙古自治区特殊服役智能机器人重点实验室呼和浩特010051

为探究数控机床主轴温度场信息与主轴热误差之间的非线性映射关系,提出一种基于人工蜂群优化算法(ABC)与广义回归神经网络的主轴热误差预测模型。首先,使用热成像技术布置温度传感器,并利用K-medoids算法对温度测点进行聚类分组,使用灰... 详细信息

为探究数控机床主轴温度场信息与主轴热误差之间的非线性映射关系,提出一种基于人工蜂群优化算法(ABC)与广义回归神经网络的主轴热误差预测模型。首先,使用热成像技术布置温度传感器,并利用K-medoids算法对温度测点进行聚类分组,使用灰色关联度分析方法计算温度与主轴热误差之间的相关程度,进而提取出最佳热敏感点;其次,引入调节因子优化ABC算法的寻优过程,使用改进后的ABC网络确定GRNN网络的最佳参数及光滑因子;最后,以三轴数控加工中心为研究对象,进行温度数据与热误差数据的采集,建立基于ABC-GRNN热误差预测模型并与优化前进行比较。热误差实验结果表明,K-medoids算法与灰色关联分析相结合,有效避免了温度测点之间的多重共线性;ABC-GRNN模型可以更准确地预测出主轴各项误差值。

关键词：数控机床主轴热误差 K-medoids算法热误差预测 ABC-GRNN模型

差动式行星滚柱丝杠副的运动特性与动力学分析

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机床与液压 2024年第13期52卷 156-163页

作者：乔冠张校民刘付乐郭世杰马尚君内蒙古工业大学内蒙古自治区先进制造技术重点实验室内蒙古呼和浩特010051 西北工业大学陕西省机电传动与控制工程实验室陕西西安710072

差动式行星滚柱丝杠副是一种将环槽传动与螺纹啮合相结合的机械传动机构。为了探究差动式行星滚柱丝杠副的动态特性,研究一种新型的差动式行星滚柱丝杠副的结构组成与运动原理,建立其三维模型,并将模型导入虚拟样机分析软件中,通过设置... 详细信息

差动式行星滚柱丝杠副是一种将环槽传动与螺纹啮合相结合的机械传动机构。为了探究差动式行星滚柱丝杠副的动态特性,研究一种新型的差动式行星滚柱丝杠副的结构组成与运动原理,建立其三维模型,并将模型导入虚拟样机分析软件中,通过设置合适的连接关系,对三维模型进行运动学及动力学仿真分析。结果表明:虚拟样机中差动式行星滚柱丝杠副的运动过程与运动分析相符合,验证了运动分析的合理性;当在螺母上施加负载时,滚柱与螺母之间的环槽设计使接触力波动更规律;随着负载的持续增大,丝杠与滚柱之间、螺母与滚柱之间的接触力波动也持续增大,加剧了机构内部的磨损情况,缩短了机构的运行寿命。

关键词：差动式行星滚柱丝杠副运动原理运动特性运动学分析动力学分析

Numerical Study on the Stress–Strain Cycle of Thermal Self-Compressing Bonding

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Chinese Journal of Mechanical Engineering 2018年第4期31卷 140-147页

作者： Yun-Hua Deng qiao guan Jun Tao Bing Wu Aeronautical Key Laboratory for Welding and Joining Technologies AVIC Beijing Aeronautical Manufacturing Technology Research Institute School of Mechanical Engineering and Automation Beihang University Science and Technology on Power Beam Process Laboratory AVIC Beijing Aeronautical Manufacturing Technology Research Institute

Thermal self-compressing bonding(TSCB) is a new solid-state bonding method pioneered by the authors. With electron beam as the non-melted heat source, previous experimental study performed on titanium alloys has proved the feasibility of TSCB. However, the thermal stress–strain process during bonding, which is of very important significance in revealing the mechanism of TSCB, was not analysed. In this paper, finite element analysis method is adopted to numerically study the thermal elasto-plastic stress–strain cycle of thermal self-compressing bonding. It is found that due to the localized heating, a non-uniform temperature distribution is formed during bonding, with the highest temperature existed on the bond interface. The expansion of high temperature materials adjacent to the bond interface are restrained by surrounding cool materials and rigid restraints, and thus an internal elasto-plastic stress–strain field is developed by itself which makes the bond interface subjected to thermal compressive action. This thermal self-compressing action combined with the high temperature on the bond interface promotes the atom diffusion across the bond interface to produce solid-state joints. Due to the relatively large plastic deformation, rigid restraint TSCB obtains sound joints in relatively short time compared to diffusion bonding.

关键词： Thermal self-compressing bonding Locally non-melted heating Thermal elasto-plastic stress–strain Atom diffusion Solid-state bonding Finite element analysis

Design and Dynamic Analysis of the Recirculating Planetary Roller Screw Mechanism

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Chinese Journal of Mechanical Engineering 2022年第4期35卷 240-255页

作者： guan qiao Rong Liao Shijie Guo Zhenghong Shi Shangjun Ma Inner Mongolia Key Laboratory of Advanced Manufacturing Technology Inner Mongolia University of TechnologyHohhot 010051China University of Cincinnati CincinnatiOH 45221USA Shaanxi Engineering Laboratory for Transmissions and Controls Northwestern Polytechnical UniversityXi’an 710072China

The recirculating planetary roller screw mechanism(RPRSM)is a transmission mechanism that engages the screw and nut threaded by multiple grooved *** this paper,frstly,the design method of RPRSM nut threadless area is proposed,and the equations related to the structural parameters of nut threadless area are *** this basis,the cross-section design method of roller,screw and nut is constructed according to the actual situation of engagements between the screw/nut and the *** adjusting the gap between the two beveled edges and that between the arc and the beveled edge,the accuracy of the thread engagements between the screw/nut and the roller can be ***,to ensure the engagements of the screw/nut and the roller,the distance equation from the center surface of the diferent rollers to the end surface of cam ring is ***,combined with the working principle and structural composition of RPRSM,the component model is established according to its relevant structural parameters,and the virtual assembly is ***,the 3D model is imported into the ADAMS simulation software for multi-rigid body *** dynamic characteristic is analyzed,and the simulated values are compared with the theoretical *** results show that the contact forces between the screw/nut and the roller are sinusoidal,mainly due to the existence of a small gap between the roller and the *** maximum collision forces between the roller and cam ring are independent from load ***,the collision force between the roller and the carrier increases as the load *** RPRSM is in the transmission process,the roller angular speed in nut threadless area begins to appear abruptly,and the position of the maximum change is at the contact between the roller and the convex platform of cam *** design of the nut threadless area and the proposed virtual assembly method can provide a theoretical guidance for RPRSM research,as well as

关键词： Recirculating planetary roller screw mechanism Nut threadless area Virtual assembly method Motion relationship Dynamic analysis

Correlation between microstructure and tensile behavior of metal–intermetallic laminate compound with different initial Ni foil thickness

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Rare Metals 2014年第2期33卷 196-202页

作者： Ya-Jie Guo Zhong-Qi Shi Yi-Ku Xu guan-Jun qiao Engineering Research Center of Transportation Materials of Ministry of Education School of Materials Science and Engineering Chang’an University State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and Engineering Xi’an Jiaotong University

Ni-base metal–intermetallic laminate composites were obtained from in situ reaction synthesis between Ni and Al foils by utilizing plasma activated sintering. The effects of Ni foil thickness on the microstructure and tensile properties of the composites were investigated. The results show that the phases forming during reaction synthesis are independent of the starting thickness of the Ni foils. However, thicker reacted layers are obtained in the samples fabricated from 100 lm Ni foils（Ni100） than those obtained in the samples from 50 lm Ni foils（Ni50）when treated at the same process. The tensile strength of Ni100 samples increases with the temperature increasing at the expense of ductility. Dissimilarly, Ni50 composites treated at higher temperatures exhibit enhanced strength and ductility. Both Ni50 and Ni100 laminate fracture in a similar mechanism. Cracking first occurs in the brittle intermetallic layers. These original cracks result in shear bands in Ni layers emitted from the crack tips, and thus producing local stress concentration, which initiates new cracks in adjacent intermetallic layers. The multiplication of cracks and shear bands leads to the failure of the laminates.

关键词： Laminates Layered composites Reaction synthesis Ni/Al

Microstructure and performance of AZ80D magnesium alloy by purification of chloride flux containing Er

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Rare Metals 2014年第5期33卷 541-546页

作者： Zhong-Jun Wang guan-qiao Su Wei-Ping Jia Qing-Xiang Yang School of Material and Metallurgy University of Science and Technology Liaoning Key Laboratory of Materials Forming and Microstructure and Properties Control Education Department in Liaoning Province State Key Laboratory of Metastable Materials Science and Technology College of Materials Science and EngineeringYanshan University

The purification effects of Er addition in chloride flux during smelting on microstructure, tensile properties, and corrosion resistance of as-cast AZ80 D magnesium alloy were carried out. The results show that Er addition in the flux can eliminate the MgO inclusions and improve the tensile properties and corrosion resistance of the alloy. Using chloride flux mixed with 8.0 wt% Er, σb and δ of the as-cast AZ80 D magnesium alloy can be improved from 150 MPa and 2.1 % to the maximum value of 230 MPa and 4.8 %, respectively. Meanwhile, the corrosion rate decreases from 1.10 to 0.12 mg·（cm^2·d）^-1 in 5 wt% NaCl solution. However, with increasing Er content in chloride flux further, φ-（Al7ErMn5） and τ-（Al66.7Mg23.3Er10） phase are formed, and the morphology of γ-（Mg17Al12） phase is modified. The coarse φ-（Al7ErMn5）phase along dendrite boundaries decreases cohesion force between dendrites, which results in the worse of tensile properties.

关键词： Er Chloride flux AZ80D Microstructure Magnesium alloy

结膜入路睑袋整复术切口缝合处理和未缝合处理的疗效分析研究

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中国医疗美容 2024年第6期14卷 1-4页

作者：邓乐曲陈威乔冠群蔡薇南京医科大学第二附属医院医疗美容科江苏南京210000

目的探讨结膜入路睑袋整复术后切口缝合处理与未缝合处理与切口并发症的关系。方法回顾性分析2018年-2022年南京医科大学第二附属医院医疗美容科160例接受结膜入路睑袋整复术的患者,对比术后切口缝合处理与切口未缝合处理的切口并发症... 详细信息

目的探讨结膜入路睑袋整复术后切口缝合处理与未缝合处理与切口并发症的关系。方法回顾性分析2018年-2022年南京医科大学第二附属医院医疗美容科160例接受结膜入路睑袋整复术的患者,对比术后切口缝合处理与切口未缝合处理的切口并发症发生情况及术后6个月恢复情况。切口并发症如延迟愈合、感染、手术3天后渗血、切口内软组织疝出、切口过长导致的对合不良、错位愈合及瘢痕不平整等。结果结膜入路睑袋整复术后切口进行缝合处理的患者缝合并未出现角膜磨损等不良反应,并且切口并发症发生率显著低于未行缝合处理的患者。结论结膜入路睑袋整复术后切口缝合与切口不缝合相比,无角膜损伤,且切口并发症发生率更低,术后6个月的愈合效果更佳,有临床推广应用价值。

关键词：睑袋结膜入路睑袋整复术结膜愈合切口缝合