高压注水在防治14~#煤层采煤工作面煤与瓦斯突出的可行性分析

通过对防治煤层瓦斯及煤与瓦斯突出治理方法的比较,分析煤层高压注水的作用机理及优点,得出了煤层高压注水方法在防治轿子山煤矿14#煤层采煤工作面煤与瓦斯突出是可行的。     

预钻式旁压试验在哈尔滨地铁一期工程中的应用

本文通过哈尔滨地铁一期工程的实例,介绍了预钻式旁压试验在工程中的现场操作,成果分析及应用。     

谈桥梁建设中高性能混凝土的应用

高性能混凝土是近期混凝土技术发展的主要方向,这种采用优质材料配制,便于浇捣、不离析、力学性能稳定、早期强度高、具有韧性和体积稳定性等性能的耐久的混凝土,特别适用于高层建筑、路桥以及暴露在严酷环境中的建筑结构。     

油气生产与生态环境协调发展的对策建议

生态环境的可持续发展是制约我国经济社会可持续发展的一大"瓶颈"。我国石油工业的发展不可避免地对生态环境产生了一定的负面影响和破坏,在未来的发展过程中,应不断以创新的理念引领社会责任,加大环保力度,大力实施节能减排、清洁生产、安全生产和节约生产,扎实推进资源节约型、环境友好型企业建设,促进人与自然的和谐发展。     

三元复合驱原油脱水技术试验研究

采出液的有效处理是制约强碱三元复合驱工业化推广的瓶颈之一。针对现场试验出现的采出液乳化、油水分离困难、悬浮固体含量过高等问题进行了研究攻关,开发了新型的游离水脱除器、电脱水供电设备和电化学脱水器,实现采出液的有效处理。     

大功率电子发射管的正确使用及延长其寿命的方法

大功率电子发射管广泛应用于广播电视发射设备及其他电子通信设备,文章介绍了采用冷打压老炼、灯丝电压调整、谐振匹配等技术方法延长电子管的使用寿命。     

Selection of influential variables in ordinal data with preponderance of zeros

Presence of excess zero in ordinal data is pervasive in areas like medical and social sciences. Unfortunately, analysis of such kind of data has so far hardly been looked into, perhaps for the reason that the underlying model that fits such data, is not a generalized linear model. Obviously some methodological developments and intensive computations are required. The current investigation is concerned with the selection of variables in such models. In many occasions where the number of predictors is quite large and some of them are not useful, the maximum likelihood approach is not the automatic choice. As, apart from the messy calculations involved, this approach fails to provide efficient estimates of the underlying parameters. The proposed penalized approach includes ?₁ penalty (LASSO) and the mixture of ?₁ and ?₂ penalties (elastic net). We propose a coordinate descent algorithm to fit a wide class of ordinal regression models and select useful variables appearing in both the ordinal regression and the logistic regression based mixing component. A rigorous discussion on the selection of predictors has been made through a simulation study. The proposed method is illustrated by analyzing the severity of driver injury from Michigan upper peninsula road accidents.     

Status quo and countermeasures of energy audit in oil and gas field enterprises

To develop energy audits in oil and gas field enterprises has important and realistic significance. Chinese energy audit in oil and gas field enterprises is still in the exploratory stage, the paper puts forward some countermeasures and proposals through the analysis on status quo to identify the shortcomings.     

国际油价波动对中国宏观经济影响的实证分析

运用格兰杰因果检验结合脉冲响应函数,来实证分析国际油价波动分别对中国宏观经济的五个变量——消费(C)、投资(I)、政府支出(G)、出口(EX)、进口(IM)的影响;同时,针对油价波动对国民经济各方面产生的影响,提出了一些建议和对策。     

越南昆江2水电站埋藏式压力钢管设计

越南昆江2水电站二级电站为典型的高水头水电站,其埋藏式压力钢管段是该电站设计施工重点部位.文章就管径管材选用、高压管道钢衬起点位置、抗内外压力稳定以及灌浆排水等方面进行了计算分析。