真空快速润麦工艺参数的试验研究

通过实验室试验,探索影响真空快速润麦的主要因素,对真空快速润麦工艺参数进行研究分析,为建设工业自动化生产线成套装备的设计提供技术支撑。     

Statistical modelling of runway incursion occurences in the United States

Runway incursions are an important aviation safety concern; between 2002 and 2015 there were 16,785 runway incursions at United States airports ranging in size from small general aviation (GA) to large commercial airline hubs. When examining airports with the 50 highest incursion count over the past 5 years, the predominant categories were large hubs, which accounted for 21 airports and general aviation (GA) airports which accounted for 16 airports. In June 2015, the Federal Aviation Administration (FAA) announced the Runway Incursion Mitigation (RIM) program to identify airport risk factors that might contribute to a runway incursion and develop strategies to help airport stakeholders mitigate those risks. Different size airports serve different aircraft fleets, serve different operating volumes, and have different resources available (both funds and technologies) for incursion mitigation. Therefore, it is valuable to determine the correlating factors that affect incursions at different size airports. This paper uses econometrics based modelling techniques to identify statistically significant factors in data provided by the (FAA) public web sites on runway incursions. The model identified statistically significant variables that correlate with incursions, based on severity, for airports categories defined by the National Plan of Integrated Airport Systems (NPIAS).The model results indicate that operational incidents (OI) are more likely at large hub airports. In contrast, at GA/non-hub airports, pilot deviations (PD) were significant for less severe incursions (severity C and D). Only one variable, “number of years since 2002”, was found to be significant for all the three airport categories; this variable was correlated with severity A incursions and indicated a statistically significant reduction in severity A incursions, despite an overall 80% increase in incursions between 2002 and 2015.     

Econometrics and equilibrium models

In Rational Econometric Man, Edward Nell and Karim Errouaki present a welcome and timely case for the view that econometrics and econometric model-building may not be the magic tools to solve all empirical questions despite what many seem to have thought they were in the 1960s. Here I examine some possible problems with econometric models that have to do with their usually taking the form of equilibrium models. Some of these problems were recognized by Trygve Haavelmo decades ago. And as Aris Spanos has recently discussed, the problems are often the result of what we say in our textbooks. Some problems have to do with what we mean by econometric parameters and others with how we use probabilities.     

利用逐步判别分析方法识别碳酸盐岩地层岩性的方法探讨——以川东上余家坝构造石炭系地层为例

碳酸盐岩储层岩性组成复杂,仅仅依靠少量的岩心、岩屑和几条常规的测井曲线资料很难准确地展现储层岩性的纵向及横向分布特征,从而影响对储层空间分布的预测。本文以上余家坝石炭系石炭系地层的岩心、岩屑录井资料为分析样本,结合对应的常规测井资料并对其进行数学处理,处理后共有12个参数供逐步判别函数筛选,经过多次的引入与剔除,建立了各类岩石的判别函数。其中灰岩、灰质云岩、云岩选择了9个参数;云质灰岩选择了10个参数。将岩性判别结果与取心井段的岩性对照,每类岩性的判别符合率都在85.39%以上,综合符合率为91.49%。说明本方法对目的层段碳酸盐岩储层岩性的识别是可行的。     

上市公司财务参数与其股价波动性关系探究

本文探究了上市公司年度股价波动性与其上一年公开财务指标的相关关系。公开财务指标主要包括六项,从不同维度反映了公司规模、资本结构、偿债能力、盈利状况、管理状况和股东情况。通过分析结果发现,若干财务指标与上市公司的股价波动性都有显著的相关关系,大部分符合预期及常识。有一些财务指标与上市公司的股价波动性长时期内表现出稳定、显著的关系。文中尝试探讨了造成这种相关性的因素。     

机构投资者对证券市场价格波动性的影响——基于Topview数据的实证研究

本文在完整的市场结构数据基础上,研究了市场波动性与机构投资者之间的相互关系。在研究数据方面,我们采用了深度、高频的Topview数据,既避免了前人在研究数据方面的以偏概全,也让我们可以采用更为先进、稳健的实证方法。我们设定了恰当的波动性度量指标,运用了稳健的因果推断方法。并用脉冲响应和方差分解的方法细腻刻画两者之间的相互关系。本文的主要结论是:机构投资者持股比率的波动对上证指数波动有显著的影响,是导致上证指数波动最为主要的原因,法人投资者和个人大户投资者持股比率的变动对上证指数的波动几乎没有影响,机构投资者持股比率波动还会向法人投资者、个人大户投资者持股比率溢出,这些表明在上海证券市场上机构投资者是市场波动的主要来源和主要原因。机构投资者的多元化、坚决推进市场的规范化改革应当成为未来政策关注的重点。     

热风炉自动控制系统的分析与实践

本文阐述了热风炉自动化控制系统中的设备,工艺和流程相关控制的要求,研究了其自动控制系统的实施步骤,以实际工作经验为例,提出了解决相关问题的措施和办法,为同行在解决此类问题时提供了相关参考。     

断面法储量计算在某金矿的应用分析

文章以断面法在胶东某金矿的应用为例,对断面法计算储量进行了详细的介绍。实例说明断面法是一种应用比较方便的储量计算方法,也能保证计算精度。分析总结断面法的优缺点,并从理论上分析了储量计算误差来源及储量计算的精度。     

高炉煤气在活性石灰回转窑中节能降耗的探讨

文章主要介绍活性石灰回转窑生产过程中,高炉煤气管网波动对生产的影响。通过增设稳压站平衡管网压力波动,稳定管网压力,增加低热值煤气用量,进而置换煤粉,降低产品能耗,保证生产稳定的使用效果。为业内通过利用低热值高炉煤气用量、降低能耗,稳定生产提供一些实践经验。     

高压风式清扫器在洗煤厂中的应用

邢台煤矿洗煤厂用风量较大,风源较多,而传统清扫器自身重量较大,使用时聚氨酯板磨损快,不易安装和进行日常维护,且维护成本较高。本文对传统清扫器进行改造升级,介绍一种利用高压风去除皮带运输机返程皮带上的残余物料的清扫装置,解决了传统清扫器的问题,大幅度节省了运行成本,效果上有明显的优点。