网络防火墙技术探讨

网络技术是高职教育教学的一个基础内容。本文就网络技术安全范畴中的网络防火墙技术做些探讨。     

双键位置对分子隧道结电子传输特性的影响

采用金属镓作为电极材料,利用分子自组装技术构筑了C7H15OH、C4H9CH=CHCH2OH、C3H7CH=CHC2H4OH、C2H5CH=CHC3H6OH和CH3CH=CHC4H8OH共5种有机分子的毛细管隧道结.在常温下,可以测得分子隧道结的I-V曲线和dI/dV-V曲线.研究表明:分子隧道结明显地体现出非线性的电子传输特性,具有整流的性能;饱和有机分子的隧道结比不饱和有机分子的隧道结更难进行电子传输;结构相似但双键位置不同的有机分子,双键位置的变化对分子隧道结电子传输特性的影响不大.     

论巴什拉元素诗学中的火

文章主要通过巴什拉的《火的精神分析》和《烛之火》这两部著作来重点探讨其中火的意象。“火”在巴氏笔下,实现了理性与感性、客观与主观的完美融合,既有清晰的不断升华的轨迹,也有因各种原因产生的混乱形象,还有其“想象哲学”生发出的多种深层意蕴。     

Test and Analysis of an Existing Tunnel Vibration Induced by Blasting Construction of Diaphragm Wall

According to the blasting construction of the diaphragm wall of Puxi approaching section of East Fuxing Road river-crossing tunnel, the monitoring project of the vibration of the existing tun-nel induced by the blasting construction is put forward, which includes the sensors’ location, moni-tor method and the vibration monitoring system. Based on the monitoring data of the explosion vibration, the vibration wave forms, velocities, acceleration responses, main frequencies and fields of measure points are analyzed under the conditions of three locations and different charge quanti-ties. According to the safety-judging standard of explosion vibration, the conclusion that the exist- ing tunnel is safe under the explosion vibration is then drawn. Furthermore, the spectrum character-istics of three explosion vibrations and the spectrum changing properties of explosion vi-bration wave transmitting in different directions are concluded, which can provide reference to similar projects.     

Simplified analysis for reflective overpressure on walls of rectangle-section tunnel due to its inner-explosion

Based on the constructing thought of the displacement model of isoparametric finite element, an extended interpolating algorithm is deduced for calculating the overpressure history of an optional point on the walls of the rectangle-section tunnel under an optional point-explosion in its internal space. According to the working principle, the overpressure histories of all nodes on the walls of a tunnel with the equal width and height of 2 m, induced by a reference-charge explosion at each node in this tunnel's cross section, are computed using the LS-DYNA software, and then are gathered to establish a reference database, which makes it possible to set optionally the positions of the explosive and the overpressure-observed point. In addition, some variation factors of peak values and durations of overpressure on the walls, reflecting some changes on the charge weight and the sizes of width and height of the section, are included in this algorithm in order to simulate approximately the overpressure responses on the walls under the optional charge weight and cross-section size. Some example analyses indicate the rapidity and validity of this method, and therefore this will bring it a good prospect in engineering application.     

大梁山隧道围岩稳定性研究

在野外隧道工程地质条件调查的基础上，通过岩体结构分析判断潜在破坏方式，经验估算方法获取节理抗剪强度参数，运用块体理论评价了大梁山隧道的围岩稳定性。     

基于多特征融合的视频火灾检测方法

相较于传统单点传感器检测火灾的方法,采用视频检测火灾更快、更可靠,而且可以提供火灾大小、增速等直观的图像信息。结合图像处理技术,设计一种可以同时检测火焰和烟雾的视频火灾检测方法。首先,通过提取移动区域的方式,并利用改进的火灾颜色模型提取出疑似火灾区域;然后,选出抗干扰能力强的火灾特征并对提取各特征的方法进行设计;最后,将火焰特征输入支持向量机进行火焰判别,将烟雾各特征与阈值比较后的结果输入可调节检测灵敏度的逻辑运算器进行烟雾判别,结合火焰与烟雾判别结果决定是否进行火灾预警。大量实验结果表明,该方法不仅可以检测明火,而且可以检测阴燃火,在检测准确率、误报率及反应时间上都有更好的表现。     

流场可视化的便携式烟风洞装置

文章介绍了一种整体长度为0.64m,重约为4kg,轻巧、便携的烟风洞装置的特点.该装置有着良好的烟气发生装置和烟气流动质量,方便的燃油补充机构和试件磁力固定结构,是流体力学学科中一种较完美的教学工具.轻巧的结构使得这种烟风洞装置可以很方便地携入教室用于教学演示.各种研究对象在风洞中的绕流情况可以很好地用高质量的数字照片显示出来,这些照片如圆柱绕流,平面叶栅的流线分布,都能较好地反映了流体力学流动基本规律;同时,通过对一个模型汽车所进行的流体力学数值计算（FLUENT）与实验对比,其结果显示出它们的流动状态吻合较好,说明这种便携式烟风洞的良好性能.     

综采工作面风巷沿空留巷技术的探讨

通过对某矿324综采工作面风巷的围岩变形规律、沿空留巷相对于综采工作面的位置在距离工作面不同位置的矿压显现特点进行分析，提出了沿空留巷的基本设计思路，为沿空留巷的设计、施工提供了理论基础。     

低氮燃烧技术在东胜烟煤锅炉中的应用

结合低氮燃烧器改造技术在北方联合电力达拉特发电厂330MW机组#3炉的应用,对低氮燃烧技术在东胜烟煤锅炉中的应用进行分析研究,为低氮燃烧的技术发展和应用提供参考。