全驱动六轮悬挂摇臂式机器人的设计及其越障性能分析

设计了一种全驱动六轮悬挂摇臂式智能移动机器人,对机器人的硬件和软件设计进行了介绍,并制做出了实验样机。通过对机器人结构的建模和理论分析,对其越障性能进行了深入的研究;实验证明,该机器人具有良好的越障能力,可作为执行搜救、信息探测和排爆等特殊任务的移动平台,具有良好的发展前景。     

Safety effects of exclusive and concurrent signal phasing for pedestrian crossing

This paper describes the estimation of pedestrian crash count and vehicle interaction severity prediction models for a sample of signalized intersections in Connecticut with either concurrent or exclusive pedestrian phasing. With concurrent phasing, pedestrians cross at the same time as motor vehicle traffic in the same direction receives a green phase, while with exclusive phasing, pedestrians cross during their own phase when all motor vehicle traffic on all approaches is stopped. Pedestrians crossing at each intersection were observed and classified according to the severity of interactions with motor vehicles. Observation intersections were selected to represent both types of signal phasing while controlling for other physical characteristics. In the nonlinear mixed models for interaction severity, pedestrians crossing on the walk signal at an exclusive signal experienced lower interaction severity compared to those crossing on the green light with concurrent phasing; however, pedestrians crossing on a green light where an exclusive phase was available experienced higher interaction severity. Intersections with concurrent phasing have fewer total pedestrian crashes than those with exclusive phasing but more crashes at higher severity levels. It is recommended that exclusive pedestrian phasing only be used at locations where pedestrians are more likely to comply.     

探索“交界空间”的可持续发展——“港珠澳大桥·香港口岸国际概念设计竞赛”的启示

“港珠澳大桥·香港口岸国际概念设计竞赛”是香港特别行政区路政署筹划的国际设计竞赛,是一次粤、港、澳三地多元文化融合的可持续探索.通过对竞赛的评述,结合对获奖和入围方案的分析,不仅阐述了香港政府对口岸建设地标化、模块化、生态化等理念的探索,同时分析了中国口岸建筑的设计变化趋势——从单一化向多元化转变,最后探讨了本次竞赛对中国口岸建设可持续发展的借鉴意义.     

架空供热管道AutoPSA软件设计计算

结合工程实例,采用AutoPSA应力分析软件,对某段跨越河流架空供热管道的一次应力、二次应力、热位移、支座反力进行了分析计算。     

矩阵变换器直接转矩控制系统的电网故障跨越能力

矩阵变换器由于其自身结构的特殊性,易受输入侧电源异常的影响。针对电网对地短路的情况,建立电网故障下的系统等效数学模型。提出一种新的开关控制策略,通过分时赋值9组双向开关的控制信号来确保矩阵变换器安全度过电网故障期。利用Matlab/Simulink来模拟矩阵变换器直接转矩控制系统在电网正常和电网故障情况下的工作状态,编写基于C语言的DSP程序和VHDL语言的FPGA程序来实现提出的控制策略。最后,设计出一套高度集成的矩阵变换器实验装置,通过实验平台验证提出的开关控制策略。仿真和实验结果表明了所提控制策略的正确性,验证了设计的矩阵变换器直接转矩控制硬件和软件系统具有电网故障跨越的能力。     

2.5维碳纤维机织酚醛树脂基摩擦材料的力学性能

以碳纤维为原料,设计织造碳纤维体积含量约50%的浅交弯联和深交联两种典型的2.5维(2.5D)机织物,优选基体材料组分和配方,采用溶液浸渍、真空辅助相结合的成型工艺,制备出新型2.5D碳纤维机织物酚醛树脂基摩擦材料。测试了预制体的密度、摩擦材料的孔隙率和密度;研究了摩擦材料弯曲、剪切性能,并分析其细观形态及破坏机理。结果表明:浅交弯联碳布密度为0.79g/cm3,深交联碳布密度为0.84g/cm3;对应的复合材料密度分别为1.44和1.37g/cm3。相同碳纤维体积含量的深交联摩擦材料的孔隙率略大于浅交弯联。在纤维体积含量相同的情况下,相较于浅交弯联摩擦材料,深交联结构具有较大的剪切强度和抗弯强度;而在弯曲载荷作用下,浅交弯联摩擦材料表现为缓慢破坏,具有较好的稳定性。     

大面积深淤泥地带管沟开挖技术

冀东油田南堡3号构造外输管道大开挖穿越石化路6 m深淤泥带,管道挖沟时淤泥回淤快,管沟无法成型。现场施工中,采用在管沟两侧打钢板桩阻止周围淤泥向管沟涌入,同时将开挖区域附近淤泥置换成山皮石后挖沟的施工方案。当用山皮石换填深度至3 m后,因淤泥回淤太快无法继续向下换填,最终采用抛石挤淤结合强夯置换处理的方法,完成了更深层淤泥的置换,实现了管沟的开挖。     

忠武输气管道襄樊支线汉江大开挖穿越施工技术

采用主河道大开挖和底拖牵引技术,成功地完成了规格为D406.4mm×9.5mm的输气管道的汉江穿越工程,文章介绍了该项工程的管沟大开挖、水下管沟测量、发送小平车及其回收、牵引力计算、浮筒结构、鹅头结构、牵引设备布置等技术要点。实践证明,管沟的准确测量、牵引力的准确计算与牵引钢丝绳的准确入沟,是汉江穿越成功的技术关键。     

Pedestrian behavior and safety on a two-stage crossing with a center refuge island and the effect of winter weather on pedestrian compliance rate

Despite a burgeoning research effort directed at understanding the effects of age, gender, disability, group size, traffic control condition and street width on pedestrian safety and compliance rate as they cross a signalized intersection, remarkably little is known about the compliance rate at a signal controlled two-stage crossing and how pedestrians react to different weather conditions. The purpose of this study was to determine whether pedestrian behavior becomes more risky in inclement weather through the investigation of street crossing behavior and compliance under different weather and road surface conditions at a busy two-stage crossing. Road crossing behavior was filmed at one eight-lane divided road strip at a downtown site in Toronto metropolitan area. The intersection was filmed unobtrusively from a rooftop by one camera set to record both oncoming near-side traffic and pedestrian movements. Pedestrian behavior and compliance rate were scored for a number of determinants of safe road crossing actions. Overall, the results show that road crossing behavior in inclement weather conditions was less safe than in fine weather. The designs of signal timing and configuration of the center refuge island also adversely influenced pedestrian behavior at this crossing, and adverse weather conditions further exacerbated the noncompliance rate. This paper presents new information on compliance rate at a two-stage crossing that emphasizes the need to consider the influence of traffic signal design and weather conditions on pedestrians’ behavior. More studies are needed to develop traffic control techniques to allow pedestrians to cross wide two-stage crossings in safety.     

米村矿28041炮放工作面过断层技术研究

针对28041炮放工作面的断层情况,研究、制定了三种过断层方案,分别论述了其优缺点。通过比较,选择出最佳过断层方案。实践证明该方案安全、经济,具有一定的借鉴价值。