基于土拱效应的筒仓土压力研究   总被引：1，自引：0，他引：1  

蒋波  应宏伟  谢康和 《科技通报》2005,21(5):624-627,632

对筒仓小主应力拱形状进行了理论分析,发现墙土摩擦角部分发挥时的小主应力拱形状较充分发挥时平缓。根据土拱形状的理论分析计算平均竖向应力,由此得到了对应不同内摩擦角和墙土摩擦角的侧土压力系数,以及筒仓侧土压力的理论公式。  相似文献   

打叶复烤二次静电除杂工艺参数仿真与验证     

秦建  张腾健  彭小冬  卢敏瑞  潘峰  秦华 《福建工程学院学报》2023,(1):14-19

建立了杂物在静电场中的运动轨迹模型,运用多物理场耦合模型对静电辊表面的电场分布、杂物在电场中的运动轨迹进行仿真分析;采用单因素实验法研究各种摩擦式静电除杂样机除杂率的影响。结果表明：试验效果与仿真结果的趋势基本一致,在环境湿度为60%RH、静电辊转速为25 r/min时,杂物的挑出率为98.77%,相较于最初的工艺参数平均挑出率提高了20.51%。研究为提高摩擦式静电除杂机的除杂率提供参考。  相似文献   

Innovative path dependence: Making sense of product and service innovation in path dependent innovation processes     

Sof Thrane  Steen Blaabjerg  Rasmus Hannemann Møller 《Research Policy》2010,39(7):932-944

This paper analyses path dependence and path creation in firm innovation focusing on the effect of cognitive frames and organisational processes. A Northern European medical device firm is analysed through a detailed assessment of the structural and processual elements of cognitive path dependence. Cognitive schemas are analysed through development of ideal typical views on innovation and through an investigation of two specific innovation projects.Drawing on sensemaking and actor network theory the paper adds to the literature in three respects. First, it provides a more systematic analysis than available in the existing literature of how cognitive frames enable and constrain firm innovation. Second, it presents an empirical analysis that contributes to a differentiation of the concept of path dependence, distinguishing between innovative path dependence and technological path dependence. Third, the paper analyses the timing of constraints and path dependence. In the cases studied the innovation approach frames the innovation problem and constraints in relation to technologies have an impact on the innovation processes later, after new technologies have been thoroughly researched.The paper illustrates how the case firm is cognitively locked into an innovation path focused on generating ever-new product versions on different technological platforms, regardless of cannibalisation among the firm's different product versions. Despite the cognitive lock-in to an innovation path the firm is unconstrained in its choice of technological platforms and paths. Firms’ innovation processes may thus simultaneously be characterised by unrestrained search processes and myopic behaviour.  相似文献   

基于UG数控加工技术在锥度弯头模具制造中的应用     

姜永梅 《黑龙江科技信息》2010,(14):36-37

锥度弯头模具精度要求高,加工难度大。基于UG软件进行数控加工设计,优化切削参数,选择合理的工件夹具,确定多次装夹的定位基准,优化了加工工艺。有效地提高了加工质量,提高加工的效率,为锥度弯头模具的精确加工提供了先进的加工方法,可供生产加工人员参考借鉴。  相似文献   

影响铝合金高速切削已加工表面粗糙度的关键因素     

温志远 《广东轻工职业技术学院学报》2006,5(3):5-7

高速切削（HSC）以高的加工效率和高的加工质量为主要特征。工件已加工表面粗糙度为评价工件表面质量的重要指标。机床、刀具与工件材料是影响高速切削已加工表面粗糙度的外在关键因素,通过对铝合金高速切削条件下工件表面粗糙度形成过程及影响因素的深入分析研究、对降低工件已加工表面粗糙度方法和手段的探索,系统地分析了切削过程中表面粗糙度的控制因素。  相似文献