摩托车和轻便摩托车用喇叭性能测试分析

摩托车和轻便摩托车用喇叭的性能测试主要包括基本声学性能和耐久性能测试,建立并执行统一、科学、合理的测试标准,是检测和评价喇叭品质的先决条件,是喇叭产品设计开发、合格检测及调试的基础,不同的试验方法,会给喇叭单品或装车性能的检测带来不同的结果,会给摩托车产品的生产、销售和出口造成一定的影响。     

思南东互通管理区大型滑坡变形机理分析与治理措施

思南东互通管理区滑坡发生后，进行了多种手段的地质勘察工作，但勘察结果似有多处矛盾，难以对这一危害巨大的滑坡做出准确定性和评价。对此，全面分析了该滑坡的变形机理，指出看似矛盾的数据其实是该滑坡变形过程和机理的真实反映，是掌握该滑坡特点的基础资料。分析结果证明:在分析滑坡变形机理的基础上，有针对性地提出了治理滑坡的措施，治理结果表明，治理措施取得了明显效果。研究成果对同类型滑坡的勘察评价及治理具有参考价值。     

A new methodology for incident detection and characterization on surface streets

In this paper, a new methodology is presented for real-time detection and characterization of incidents on surface streets. The proposed automatic incident detection approach is capable of detecting incidents promptly as well as characterizing incidents in terms of time-varying lane-changing fractions and queue lengths in blocked lanes, lanes blocked due to incidents, and incident duration. The architecture of the proposed incident detection approach consists of three sequential procedures: (1) Symptom Identification for identification of incident symptoms, (2) Signal Processing for real-time prediction of incident-related lane traffic characteristics and (3) Pattern Recognition for incident recognition. Lane traffic counts and occupancy are the only two major types of input data, which can be readily collected from point detectors. The primary techniques utilized in this paper include: (1) a discrete-time, nonlinear, stochastic system with boundary constraints to predict real-time lane-changing fractions and queue lengths and (2) a pattern-recognition-based algorithm employing modified sequential probability ratio tests (MSPRT) to detect incidents. Off-line tests based on simulated as well as video-based real data were conducted to assess the performance of the proposed algorithm. The test results have indicated the feasibility of achieving real-time incident detection using the proposed methodology.     

Simulation of dynamic interaction between train and railway turnout

Dynamic train–track interaction is more complex in railway turnouts (switches and crossings) than that in ordinary tangent or curved tracks. Multiple contacts between wheel and rail are common, and severe impact loads with broad frequency contents are induced, when nominal wheel–rail contact conditions are disturbed because of the continuous variation in rail profiles and the discontinuities in the crossing panel. The absence of transition curves at the entry and exit of the turnout, and the cant deficiency, leads to large wheel–rail contact forces and passenger discomfort when the train is switching into the turnout track. Two alternative multibody system (MBS) models of dynamic interaction between train and a standard turnout design are developed. The first model is derived using a commercial MBS software. The second model is based on a multibody dynamics formulation, which may account for the structural flexibility of train and track components (based on finite element models and coordinate reduction methods). The variation in rail profile is accounted for by sampling the cross-section of each rail at several positions along the turnout. Contact between the back of the wheel flange and the check rail, when the wheelset is steered through the crossing, is considered. Good agreement in results from the two models is observed when the track model is taken as rigid.     

工程造价人员做好工程经济工作的新思路

工程造价控制是一项涉及立项、设计、施工、结算等内容的系统工程，采取的预防措施和控制手段应贯穿于工程项目建设的全过程。此文针对工程建设领域多年来存在的工程技术与经济分离的现象，从工程造价人员整体素质不高，在项目建设过程中参与的深度和广度不够，创新服务能力弱，急需改进和提高等方面进行分析与探讨，并提出工程造价人员要不断学习和掌握一定的工程技术，与设计人员密切配合，在提高编制概预算水平的基础上，向工程经济与技术相结合的模式发展，开创新理念的工作思路，这一思路可促使工程投资效益最大化。     

路政管理为工程建设服务的体会

阐述提前介入容量县至岑溪一级公路梧州工程建设的路政管理，对推动施工顺利进行和确保良好的路容路貌的体会。     

论独立董事和监事会在上市公司监督机制中的关系

独立董事和监事会制度在我国上市公司的并存中存在职能定义不清、职能交叉等问题,两种制衡机制在运行的过程中产生许多矛盾。文中分析了我国上市公司的独立董事制度和监事会制度在并存过程中存在的冲突,并对其如何角色定位和如何进行职能协调提出了相应的对策。     

地铁垂直交叉隧道工程施工

研究目的:随着越来越多的城市都将地下交通网线作为解决交通拥挤的最为有效手段,地铁隧道线路垂直交叉施工情况日益增多,这给地铁隧道施工带来更多的风险和挑战。本文就垂直交叉施工中的重难点及施工中应采取的措施进行研究,以供地铁隧道施工参考。研究结论:交叉隧道施工中,超前预报、爆破控制、监控量测等施工手段是极为有效的方法,三者缺一不可、相辅相成,其中爆破控制是关键,超前预报与监控量测是重点。只有通过超前预报提前了解掌子面内部实际地质情况,并根据监控量测数据及时掌握地面沉降变化情况,才能够制定出最为合理有效的爆破控制参数,排除潜在风险,保证交叉隧道顺利施工。     

铁路综合视频监控系统设计的用户需求研究

结合武汉铁路局京广北线综合视频监控系统工程设计,整理、归纳并对用户需求进行研究,仅供工程设计参考。     

基于hyperworks的前桥有限元分析

汽车前桥工字梁是汽车中的重要部件，应具有足够的强度和刚度。首先按照厂家所提供的AUTOCAD图纸在UG中建立桥壳几何模型，然后在Hyperworks软件中进行网络划分，并进行加载和约束，完成有限元计算分析。