Canadian university students in wireless classrooms: What do they do on their laptops and does it really matter?

Two studies were conducted to examine what undergraduate students do on their laptops during class time and the extent to which laptop usage behaviors are associated with academic success. In Study 1, a sample of 1129 students from a Canadian university completed a survey measuring prototypical behaviors emitted on laptops during class time. Results of factor analyses indicated that laptop behaviors can be regrouped in two dimensions: School related and school unrelated laptop utilization. School unrelated laptop behaviors were significantly associated with lower levels of self-reported academic achievement and satisfaction. School related laptop behaviors were positively associated with academic satisfaction. These results were invariant across different faculties on campus. In Study 2, another sample of 88 students was recruited to examine the longitudinal association between laptop behaviors and semester grade point average obtained at the end of the semester. Results of Study 2 showed that school unrelated laptop behaviors were prospectively associated with lower semester grade point average, even after controlling for a series of potentially confounding influences (i.e., self-regulation failure, motivational deficit, disorganized learning, internet addiction, and school disenchantment). Overall, these results provide theoretically important support to suggest that in-class laptop utilization is a unique and contemporary mode of learning that should not be treated as an epiphenomenon merely accountable and reducible to other sources of psychological influences.     

Trennfunktion für den stationären Siebprozess

A new grade efficiency function T(x, α′, β) for the stationary screening process is presented. It is a function of particle size x, separation sharpness α′, and the newly introduced separation efficiency β. With this new grade efficiency, the screening classification process can be described exactly. Especially in the fine and coarse material range, a very good correlation with the measured values can be observed. A comparison of the grade efficiency function with separation sharpness α′, separation efficiency β and only with the measure for separation efficiency has shown that the new grade efficiency allows a significant improvement in the characterization of the stationary screen classification process. The new model of the grade efficiency function T(x, α′, β) shows a significant higher correlation with the measured values compared to other models, and is therefore very well suited to describe a grade efficiency for the stationary screening process.     

基于等级变异的克隆选择算法

提出一种克隆选择算法--基于等级变异的克隆选择算法. 为提高进化中变异的有效性, 算法将变异尺度分成若干等级, 低等级变异有利于跳出局部最优解, 实现全局寻优; 高等级变异有利于局部的高精度寻优.此外, 算法在进化过程中记忆父抗体的变异尺度等级等信息, 并制定有效的变异策略运用这些信息以指导后续进化过程. 采用标准函数测试并与其它优化算法进行对比． 实验结果表明,该算法具有收敛速度快、全局搜索能力强、精度高和鲁棒性好的优点．     

锌精矿再磨再选降硅浮选试验研究

针对乌拉根铅锌矿生产现场锌精矿含硅(指二氧化硅)高的问题,进行了相关试验研究,确定了锌精矿再磨后,分两步产出锌精矿的工艺流程(药剂制度:锌精1水玻璃30g/t,硫酸铜20 g/t;锌精2丁黄药5 g/t,松醇油1 g/t)锌作业回收率98.13%,品位从53.46%提高到60.95%,锌精矿含硅从11.62%降低到3.74%,为该铅锌选矿厂提质降硅提供了技术参考依据     

无线传感网基于梯度的非均匀分簇算法研究

为了缓解在无线传感网“多对一”的数据收集流量模式下,产生的近SINK的“热区”问题,提出一种基于梯度的非均匀分簇算法。首先,分析此种数据汇集模式的数据流量特性,给出节点至Sink跳数（梯度）与其负担的流量的关系,接着,从不同梯度的簇头负载与相同梯度的负载两方面着手,设计了负载平衡的非均匀分簇调整算法（WUC）,节点依据自身的梯度确定分簇的规模,以多权值优化的方式成簇。仿真结果表明,在本文的仿真场景设置下,网络中不同梯度的簇头的流量负载标准差降低了9倍左右。网络的负载平衡有了显著的改善。     

矿石品位指标优化方法在二峰山铁矿的应用

阐述在实用磁滑轮预选工艺条件下对入选品位，截止出矿品位，边界品位进行优化的方法和依据，介绍二峰山铁矿选矿厂进行矿石品位优化的实际情况，实践证明优化矿石品位不但可以提高经济效益，而且可以充分利用矿资源。     

基于三维地质统计学的矿床建模实践研究

结合一个实际的铜铁共生矿床，对应用三维地质统计学方法研究矿床建模工作涉及的若干技术与方法。首先进行了合理而有效的样品组合计算，同时研究了该矿铜，铁样品品位的分布规律，通过交叉验证工作，得出了相应铁原样品位及铜的对数转换品位进行矿床建模的结论，并分析建立了这2种元素的品位模型，然后对建模结果与实际矿床进行了比较，其结果表明了建模的准确性，最后得出了应用地质统计学方法进行矿床建模工作的一些有意义的结论和建议。     

工业低品位余热应用于城市集中供热的技术途径与潜力研究

本文以国内某钢铁厂为例,探讨了工业余热梯级综合利用方式问题,并研究了将钢铁厂低品位余热进行回收并用于城镇集中供热的技术途径及经济性,对国内钢铁行业内低品位余热资源的种类与规模进行了初步评估,指出钢铁厂等高耗能企业通过低品位余热供热可为大规模解决我国北方地区城镇集中供热提供一种具有循环经济属性的新型供热方式,并具有重要的节能减排、降耗增效的意义.     

低配棉36．4tex转杯纺产品的工艺研究

在对转杯纺工艺理论和试验研究基础上,探讨了低配棉36．4tex转杯纺产品的工艺流程设计和各工序的主要技术措施。在生产中,各工序通过优化配置工艺参数,保证了纺纱的顺利进行,提高了成纱质量。