热轧齿轮齿形拉尖的影响因素

针对工艺参数对热轧齿轮齿形拉尖的影响,采用有限元数值模拟分析方法,引入无量纲量影响因子,对不同工况下热轧齿轮齿顶相对拉高进行了方差分析,并对不同影响因素进行了显著性分析.结果表明,轧辊转速和摩擦系数对齿形拉尖的影响最为显著,其次为进给速度和轧辊齿顶圆角,而轧制温度和坯料材料对齿形拉尖的影响并不显著.通过提高坯料材料的变形抗力或减小摩擦系数,均可以削弱热轧齿轮的齿形拉尖现象,且减小摩擦系数的影响效果更为明显,进一步验证了影响因素显著性分析的准确性.     

基于FANP的私用飞行驾驶员安全驾驶行为评价模型

为了正确评价私用飞行员的安全驾驶行为,在系统分析飞行运行全过程的基础上,建立了基于模糊网络分析法(FANP)的私用驾驶员安全驾驶行为评价模型.针对模型中三角模糊数互补判断矩阵一致性检验过于复杂的问题,引入了最小方差的非线性规划模型,通过求取最优解以简化计算,获得可信度较高的评价指标权重.以某航校飞行学员的评价为实例进行实证分析,结果表明,该模型较传统评价方式更全面、客观,有助于飞行员的安全驾驶行为训练.     

基于用户分层的手持工具感知差异的研究

为探索设计者、供应商和终端用户对手持工具的感知差异,以钳子为研究对象,进行视觉感官试验、触觉感官试验和操作体验测试,运用因子分析法和方差分析法进行对比分析,得出用于钳子评价的语义因子,发现设计者和终端用户对钳子的可用性和便携性方面的感知差异较显著,在使用前后的复杂性和弹性的评价差异较大。     

A discrete-event model to simulate the effect of truck bunching due to payload variance on cycle time,hauled mine materials and fuel consumption

Data collected from truck payload management systems at various surface mines shows that the payload variance is significant and must be considered in analysing the mine productivity,energy consumption,greenhouse gas emissions and associated cost.Payload variance causes significant differences in gross vehicle weights.Heavily loaded trucks travel slower up ramps than lightly loaded trucks.Faster trucks are slowed by the presence of slower trucks,resulting in‘bunching’,production losses and increasing fuel consumptions.This paper simulates the truck bunching phenomena in large surface mines to improve truck and shovel systems’efficiency and minimise fuel consumption.The study concentrated on completing a practical simulation model based on a discrete event method which is most commonly used in this field of research in other industries.The simulation model has been validated by a dataset collected from a large surface mine in Arizona state,USA.The results have shown that there is a good agreement between the actual and estimated values of investigated parameters.     

粗纱工艺参数的优化配置研究

对粗纱工序影响成纱质量的工艺参数进行了全方位的分析,发现影响粗纱成纱质量的工艺参数主要有锭翼速度、前区隔距、主牵伸区隔距、后区隔距、后区牵伸倍数、上下销钳口隔距和捻系数等.针对这些工艺参数在粗纱机上进行正交试验,纺制普梳纯棉18.2 tex纱线,对产生的数据进行极差和方差分析,优选出能够获得最佳粗纱成纱质量的工艺参数.对得到的工艺参数上机试验并纺制成细纱测试其质量,其成纱质量数值在乌斯特2007年公报5%水平以内,说明优选的工艺参数可以应用于生产实践,对生产企业探索其他品种的工艺参数配置具有理论和实践指导意义.     

关于减法补数复合函数的均值估计

用初等方法和解析方法研究类似于Smarandache减法补数的复合函数性质,获得了3个较强的均值公式,完善了加法补函数与减法补函数在数论中的研究和运用。     

复杂系统平均寿命的估计和性质

根据已知的基于最小路径或最小割集复杂系统可靠度函数的解析表达式,给出当子系统寿命分布服从指数分布时,系统平均寿命的表达式.利用这一表达形式,在子系统寿命变量服从指数分布条件下,分别就完全数据和截尾数据两种情况,给出了系统平均寿命的估计,并对估计性质进行了研究.并在完全数据下,给出了估计的渐近分布.     

水平切片解释方法在焦作井田构造复杂区的应用

河南焦作某矿地处焦作煤田东部,该矿东三盘区地质构造复杂,主采的2号煤层底板与L_8灰岩平均间距仅20m,与奥灰顶界面平均间距约100m,因此断层的存在极易导通奥灰水,形成较大的水患事故。故查明区内构造分布情况十分必要。本文重点介绍了用三维地震常规解释方法结合偏移及方差数据体水平切片解释方法在构造复杂区的应用情况,具有一定的推广意义。     

采用锥型砧座测定微小钢球的硬度及其方差分析

在WELSON－A653T洛氏硬度计上,采用自制凹锥形砧座测试微小钢球的硬度,解决了微小钢球在常用平面砧座和V形砧座上易打滑,不易固定,致使压头打在砧座上,损坏压头和砧座的难题,并采用方差分析的方法,将该法与传统试验方法相比较,验证其检测结果与传统法所获得检验结果无显著性差异。     

Insight into spontaneous recurrent calcium waves in a 3-D cardiac cell based on analysis of a 1-D deterministic model

Calcium dynamics in a cardiac cell are described by a system of 3-D non-linear stochastic partial differential equations. To obtain solutions that have biophysical properties, it is necessary to explore the model parameter space. To decrease the complexity of the parameter search, we reduce the 3-D stochastic model to a 1-D deterministic model. The reduction of the problem from 3-D to 1-D is done through an asymptotic approximation after non-dimensionalization and based on rational biophysical assumptions of the 3-D domain; the stochastic to deterministic transformation is based on the regular property of the 3-D solution. The result of the model reduction proves very effective in reducing the time required to get qualitative as well as quantitative information about parameter regions in the 3-D stochastic model including calcium dynamics (sparks, wave propagation, and recovery) observed in cardiac cells.