煤矿井巷工程质量控制的系统特性分析

我国煤矿的工程质量一直是社会关注的焦点,因为最近几年我国煤矿频频发生重大的安全事故,这就使得许多的矿井作业安全问题日益的暴露了出来。而且在煤矿开采过程中其本身就是一个高危作业,再加之许多的人为操作的失误,很容易造成重大的安全事故,所以安全作业系数根本就不好控制。文章主要从煤矿的安全生产和维护工程质量方面分析。     

煤矿工程造价竞标的高效研究

本文在分析和研究煤矿工程造价的基础上,介绍了其含义与职能,并进一步探讨了煤矿工程造价竞标的意义和作用。     

浅析软煤层中顶层综采工作面回采初期技术管理

目前正处于煤炭行业的寒潮时期,各地煤炭企业亏损严重。为了响应国家的安全生产方针,煤炭企业在该时期生产过程中安全方面更不敢出一丝的问题。由于综采工艺相比其他采煤工艺而言大大提高了施工人员的安全系数。所以,综采工艺往往是工作面回采的首选。河南能源化工集团焦煤公司中马村矿同样采用了综采工艺对211021工作面进行回采。211021综采工作面为顶层工作面,并且所采煤层煤质较软,初采初放期间遇到了三条断层。下面就211021综采工作面回采初期的技术管理进行简要的分析总结。     

大倾角综采工作面撤除工艺优化与应用

大倾角综采工作面设备快速撤除一直是煤矿生产的技术难题。本文针对刘庄煤矿121106俯采工作面撤除难题,通过合理优化工作面设备撤除整体路线以及撤除施工工艺,实现了工作面设备的安全快速撤除。     

基于多维频谱地图的干扰规避

针对复杂电磁环境下卫星移动通信系统可靠通信需求，利用频谱地图多维数据呈现优势，提出了基于多维频谱地图的干扰规避方法。通过建立卫星移动通信系统波束、时隙、子频带、干扰强度等多维信息关联的频谱地图，利用数据挖掘方法对频谱可用情况进行预测，基于预测结果及用户QoS(Quality of Service)需求生成干扰规避策略，通过星地联合频谱资源调配实现系统干扰规避。该方法为卫星移动通信系统干扰规避提供了一种全新的思路，可提升卫星移动通信系统干扰防护能力。     

Incorporating textual information in customer churn prediction models based on a convolutional neural network

This study investigates the value added by incorporating textual data into customer churn prediction (CCP) models. It extends the previous literature by benchmarking convolutional neural networks (CNNs) against current best practices for analyzing textual data in CCP, and, using real life data from a European financial services provider, validates a framework that explains how textual data can be incorporated in a predictive model. First, the results confirm previous research showing that the inclusion of textual data in a CCP model improves its predictive performance. Second, CNNs outperform current best practices for text mining in CCP. Third, textual data are an important source of data for CCP, but unstructured textual data alone cannot create churn prediction models that are competitive with models that use traditional structured data. A calculation of the additional profit obtained from a customer retention campaign through the inclusion of textual information can be used by practitioners directly to help them make more informed decisions on whether to invest in text mining.     

Employing structural topic modelling to explore perceived service quality attributes in Airbnb accommodation

This study employs the structural topic model to extract service quality attributes from 242,020 Airbnb reviews in Malaysia. 22 service related topics were extracted from the corpus and four topics have not appeared in previous Airbnb studies. A widely used modified SERVQUAL questionnaire (MSQ) is cross-validated in this study by comparing its service quality attributes with the results of the topic modelling, which indicates that this MSQ can cover general Airbnb service quality attributes. This study also examines the different preferences of Malaysian and international Airbnb users and the changing patterns of the top six service quality attributes during a five-year period. The findings reveal that Malaysian Airbnb users care more about the appearance and location of the property, and international Airbnb users pay more attention to whether the property can accommodate a group of people. In addition, communication with the host is found to play an increasingly important role in Airbnb users’ lodging experiences.     

以煤为原料的甲醇制备工艺研究

本文对以煤为原料的甲醇制备工艺研究,有利于指导煤制甲醇生产工艺实践,有助于煤制甲醇生产工艺的改进和提高。