共查询到18条相似文献,搜索用时 93 毫秒
1.
为了研究在不同工况下牙膏纸箱的堆码层数和堆码时间的关系,指导牙膏纸箱的储运,通过对样本的堆码试验,利用统计分析方法对其堆码中产生整体蠕变的时间数据进行处理,然后在一定置信度下进行参数和区间估计,从而得出牙膏纸箱堆码时产生蠕变的大小和堆码时间的关系,确保牙膏纸箱堆码整体蠕变时间确定的可靠性. 相似文献
2.
牙膏纸箱堆码抗压可靠性设计初探 总被引:1,自引:1,他引:0
模拟牙膏纸箱实际堆码进行长时间抗压试验,获得纸箱压溃临界蠕变变形量,采用数理统计方法确定了该种纸箱压溃临界蠕变变形量的概率分布及其数字特征,提出了牙膏纸箱堆码抗压可靠性设计参数。 相似文献
3.
4.
瓦楞纸箱堆码性能分析 总被引:3,自引:3,他引:0
以平齐堆码的瓦楞纸箱为对象,针对不同的存储周期,研究了堆码时间对瓦楞纸箱堆码强度的影响。运用静载荷堆码试验方法,研究了堆码时间与底层瓦楞纸箱变形量的关系,通过回归分析得到了关系方程,确定了堆码时间较长的纸箱的变形量的预测方法。研究了平齐堆码瓦楞纸箱承载耐久时间与固定载荷的关系,并绘制了其关系曲线,通过回归分析得到了瓦楞纸箱压溃时间的公式。 相似文献
5.
瓦楞纸板和纸箱蠕变关系的研究 总被引:2,自引:2,他引:0
通过运用马基公式和瓦楞纸板和纸箱的蠕变模型,分析得到瓦楞纸板和纸箱蠕变可持续时间之间是一种线性关系,并用实验对这一结论进行了验证。为瓦楞纸板和纸箱蠕变时间关系建立提供了一种新的方式。 相似文献
6.
7.
《软包装商情》2019,(4)
为研究石膏金蛋的动静态力学性能,优化运输包装结构,减少石膏金蛋在运输过程中破损的风险,通过压缩实验和跌落实验分析石膏金蛋的力学性能,选择合适的材料作为缓冲包装。以瓦楞纸箱作为外包装,设计纸箱尺寸,计算抗压强度。通过对瓦楞纸箱堆码强度进行校核计算,可知纸箱抗压强度远大于堆码载荷,设计安全。由此可以得出结论 :跌落高度和缓冲材料的厚度均对石膏金蛋的破损有明显的影响。采用瓦楞纸板隔条结构和聚乙烯泡沫材料(expandable polyethylene, EPE)作为内部包装、AB型瓦楞纸板作外包装的石膏金蛋整体运输包装设计具有可行性。研究结果对石膏金蛋包装规格标准化出厂以及产品装卸、运输、仓储的机械化、自动化有重要指导意义。 相似文献
8.
9.
瓦楞纸箱结构设计及其优化方法 总被引:8,自引:8,他引:0
为了有效解决瓦楞纸箱结构设计和选料问题,研究了结构设计的方法与流程,结构尺寸和选料的优化方法等.通过分析物品的排列方向、数目、纸箱体积与纸板用料面积的关系,研究了纸箱的理想尺寸比例的数学模型;通过抗压和堆码强度计算方法,研究了纸箱选料方法;在综合分析强度、美学等因素的基础上,研究了纸箱结构尺寸优化方法,同时提出了基于遗传算法的纸箱优化选料方法,建立了用料成本的经济性评价方法. 相似文献
10.
11.
Mathematical models and solution methods for optimal container terminal yard layouts 总被引:1,自引:1,他引:0
In this paper, we introduce an integer linear program for planning the layout of container yards. We concentrate on a special
layout class of container yards which we call yard layout with transfer lanes. For those layouts typically rubber tired gantry
cranes are used for stacking operations and trucks for horizontal transports. We show that the optimization model can be formulated
as a special type of a resource constrained shortest path problem for which the LP relaxation always has at least one integer
optimal solution. This model is restricted to a rectangular storage yard which allows a linear formulation. For an arbitrary
shaped container yard we adopt the model and develop a variable neighborhood descent (VND) heuristic for solving non-rectangular
instances. Concerning the rectangular case, we show that the VND heuristic achieves optimal solutions for 38% of the realistic
test instances. 相似文献
12.
Asynchronized automated material handling systems, e.g. automated electrified monorail systems and automated guided vehicle systems, have been playing important roles in manufacturing. Reliability becomes a critical issue as manufacturing enterprises are moving toward automation. In the past, reliability tissue has not been analysed explicitly for these types of systems. In this research, a new measure was proposed to specify reliability. A mixed integer programming model was developed to design flow paths for a special class of material handling systems, i.e. single-loop dual-rail systems. The model can be used to design systems with higher reliability. The model and application procedure in design and analysis were demonstrated through two case studies. 相似文献
13.
14.
Chunhong Chen 《Nanotechnology, IEEE Transactions on》2007,6(3):303-308
To make digital circuits with unreliable devices more reliable has been a design challenge, especially for today's nanometer-scale technologies. In this paper, we discuss gate replication architecture towards increasing the reliability of individual logic gates. While this architecture is similar to, and a special case of, conventional N-modular redundancy scheme, we provide more interpretation and extend it to the situation where N is an even integer by using threshold logic gate instead of majority voter. We also study the reliability models for generic gates with single-electron tunneling (SET) technology. Both analysis and numerical evaluation suggest that while more redundancy leads to higher reliability in general, the improvement rate depends on individual gate failure rates 相似文献
15.
16.
提高大型木包装箱堆码强度的侧立柱改进设计方法 总被引:1,自引:1,他引:0
结合材料力学的受力分析方法,以不同的底座形式及其对应的不同的包装箱尺寸为例,对包装箱分别承受均布载荷和集中载荷条件下的堆码强度进行受力分析,校核侧立柱的堆码强度,改进堆码强度的设计方法,为堆码强度的设计、分析研究提供参考依据. 相似文献
17.
A. M. Siddiqui 《Acta Mechanica》1998,129(3-4):263-271
Summary Inverse solutions for the plane steady creeping flow of a second-order fluid are obtained by assuming certain forms of vorticity and its Laplacian. Expressions for streamlines are given explicitly in each case. 相似文献
18.
目的 通过设计双头平推柱塞式灌装机构,进一步提升牙膏等黏稠膏体的灌装生产效率,同时研究牙膏流变特性对灌装推力的影响,以解决当前牙膏等粘稠膏体灌装速度、精度低等问题。方法 首先选取市场占有率较高的品牌牙膏进行流变试验,然后采用经典非牛顿流体本构方程拟合获得流变曲线,最后采用数值模拟物料灌装挤出过程,获得所需要的最大灌装推力。结果 研究表明,牙膏属于非牛顿流体且具有剪切稀化的流变特性,与幂律流变模型(Powder Law黏度模型)拟合相关性为0.999 2。在最大灌装容量为200 mL、最大灌装速度为0.337 m/s时,所需推力为1 681 N。结论 可为非牛顿流体的灌装机构设计提供理论指导。 相似文献