矿山微差爆破和新型起爆系统

根据本人这几年从事露天、地下矿山爆破技术研究和实践的经验,对矿山爆破的目标、微差爆破作用方式、微差间隔时间选择和新型低能导爆索微差起爆系统作了一些分析,特别介绍了一种新型起爆系统的工业试验情况,以此为矿山应用提供参考。     

A Method for Estimating the Synchronization of a Mild Multipoint Synchronous Initiation Circuit

Multipoint synchronous initiation has widespread applications in the aerospace and defense fields. However, dispersion is always present in the function time of multipoint synchronous initiation systems. This dispersion could significantly affect weapon efficiency or aerospace mission success; as a result, determining how to estimate and control the function time dispersion of multipoint initiation systems makes considerable sense. In this work, a method for estimating the synchronization of a mild multipoint synchronous initiation circuit was proposed. This method is based on the calculations of detonation velocity dispersion and interface propagating time dispersion from the dispersion relationship and the experimental results of “one input, two outputs” initiation circuits. The obtained estimation of the synchronization of a higher level multipoint initiation circuit coincides well with the experiment test result. The good coincidence shows that the method proposed in this work can be used to predict the synchronization of mild multipoint initiation circuits.     

麻子坑采场410及420台阶基建工程硐室爆破

分析冯家峪铁矿麻子坑采场矿岩爆破条件，介绍了其４１０及４２０台阶基建工程硐室爆破的药室设计、导硐布置、起爆及硐室填塞方案，并对爆破效果进行了综合评价。     

V型多排深孔逐孔延时后倾式起爆技术与应用

基于炸药管制政策问题和岩石资源特征,湖州新开元碎石有限公司设计了V型多排深孔逐孔延时后倾式起爆的爆破方案。实践表明该方案有效地降低了炸药单耗,改善了爆破效果,值得推广。     

An active direction control method in rotating detonation combustor

rotating direction of detonation waves is one of the essential characteristics of the unsteady flow fields in the rotating detonation combustors (RDCs). However, it changes over time and is challenging to predict. Pre-detonator is commonly used to initiate the RDC in experiments. Intuitively, the detonation wave should continue in the direction of the pre-detonator. Unfortunately, experimental results often contradict this expectation. Three-dimensional numerical simulations of a rotating detonation combustor installed with a pre-detonator are performed in the present study. The numerical experiments show that the pre-detonator induces two counter-rotating detonation waves in the annular chamber and fails in fixed-direction initiation. Furthermore, we propose an active direction control method in the present study. This method utilizes the pre-detonator as a control device and successfully regulates the detonation waves along the pre-detonator direction. The active direction control method allows adjusting the propagating direction of detonation waves anytime during the RDC operation. By this method, multiple waves tend to be produced in the flow field, enhancing the stability of the rotating detonation combustor.     

定制加权公平队列调度下的SIP DoS攻击防御机制

SIP由于协议的开放性而容易受到DoS洪泛攻击,队列调度方案可以大大减轻洪泛攻击对SIP服务器的影响。通过对SIP消息特征和现有队列调度方案的分析,提出了一种基于定制加权公平队列调度的SIP DoS洪泛攻击防御机制,并对该机制进行了性能仿真。仿真结果显示该方案在防御INVITE洪泛攻击方面比单队列和优先级队列更为有效。     

一种融合GPS信息的手机流媒体通信和传输系统

针对目前智能手机定位监控和实时视频指挥系统分散无法整合的问题,在Android平台上提出一种融合GPS定位数据基于无线网络的流媒体通信架构。采用H.264格式和基于RTP/RTCP协议进行流媒体的压缩、分包和管理,把GPS定位等复合信息存储在RTP扩展包内与音频数据组包传输,智能终端既能完成视频通话也能同步传输和展示GPS定位信息。实践证明融合GPS信息对音视频传输延迟影响小、集成度高,并可扩展融合图片和文字数据,应用广泛。     

一台1000m3液化石油气球罐裂纹的成因分析及裂纹修复

本文采用磁粉探伤技术对1000m3液化石油气球罐进行无损检测,并结合金相试验结果对球罐横向裂纹萌生及扩展原因进行了分析。分析表明,现场安装时组对和焊接工艺控制不严格、焊后热处理未达预期目标是造成焊缝产生大量延迟裂纹的主要原因。     

构建基于SIP与嵌入式多核架构的流媒体服务器

结合当前最流行且得到业界广泛认可的嵌入式数字视频系统框架——达芬奇技术框架,基于达芬奇技术典型处理器TMS20DM6446平台构建流媒体服务器,用AVS、H.264和MPEG4做视频压缩,用G.711和G.728做音频压缩算法,用SIP做访问控制协议,用RTP/RTCP和UDP等做媒体控制和传输协议;完成具有完整实时编码、录像存储、实时监控、远程控制等功能的网络音视频监控系统。该系统具有高性能、高编码效率、低成本、低延迟、强实时性等特点,能够在广域网上流畅运行。     

燃爆诱导水力压裂多裂缝耦合起裂规律

为了明确多相位裂缝组合下的应力干扰作用及其对后续水力压裂裂缝起裂压力的影响,基于原有预存单条诱导裂缝的应力场计算模型建立预存多条诱导裂缝的耦合应力场计算模型,分析诱导应力影响下的井周周向应力场变化规律,再结合断裂力学判据计算后续水力压裂预存裂缝的起裂压力,并对预存裂缝长度、相位、水平主应力差异系数及预存裂缝条数等4个因素对预存裂缝起裂压力的影响进行了分析。研究结果表明:(1)预存裂缝后近裂缝区域周向应力差明显增大,甚至出现水平主应力反转;(2)随新增预存裂缝长度增加,原预存裂缝起裂压力先增后降,在新增预存裂缝长度增加到原预存裂缝长度时,原预存裂缝起裂压力迅速降低,而后下降趋势变平缓;(3)高相位裂缝的起裂压力大于低相位裂缝的起裂压力;(4)随着裂缝条数的增加,新增预存裂缝起裂压力逐渐降低,但起裂压力差减小的趋势不明显;(5)多相位裂缝的应力干扰作用影响裂缝的起裂压力,较长高相位裂缝和较短低相位裂缝均有利于多相位裂缝的同时起裂;(6)多裂缝同步延伸会产生更为复杂的应力干扰作用,激发水力压裂复杂缝网的演化,实现均衡的压裂改造。结论认为,该研究成果可为燃爆诱导压裂射孔相位、诱导裂缝规模及后续水力压裂施工泵压等压裂施工设计提供理论指导。