HEC-RAS在河道整治工程方案优化中的应用

为分析论证绣源河景观整治方案的可行性和合理性,尽可能减少景观工程对河道行洪能力的影响,利用HEC -RAS软件对整治后的河道水面线进行了多方案分析计算.结果表明:原8#滚水坝设计方案存在一定问题,造成上游水位壅高值偏大,给河道两岸堤防及跨河桥梁的防洪安全带来隐患;若将8#滚水坝加长至300 m,坝顶高程和坝前河底高程不变,则经十东路桥和章丘大道桥梁底标高均能满足100 a一遇洪水防洪要求,但待建桥的梁底标高不能满足50 a一遇洪水防洪要求,需对其进行调整.     

天津宝钢钢材配送有限公司厂区地面沉降分析

通过对天津宝钢钢材配送有限公司厂房C跨、办公楼大厅、办公楼散水坡、踏步台阶、厂区院内等地面的不均匀沉降现状调查,及对厂区前期勘探资料、设计资料、生产现状的研究,采用地面沉降监测及地下水位观测的方法,从南水北调施工降水、厂区地基土体特性、使用情况及厂房内施工降水等几个方面对天津宝钢地面沉降进行综合分析,找出了厂区地面沉降...     

毛细式透排水带排水能力试验研究

主要介绍了毛细式透排水带和不同渗透特性土壤组合,在不同倾角布置时的反滤排水试验成果,为毛细式透排水带应用于土坝坡脚反滤排水体改造提供科学依据。     

采用多曲线拟合的柔性体建模仿真方法

提出了一种多曲线拟合的数学建模方法,用于在仿真中快速建立柔性物体受力的形变模型。该方法根据柔性体的形变特性将其外形轮廓分为多个部分;然后使用不同的简单曲线拟合各部分轮廓的形状,并通过改变拟合曲线的参数使得曲线形状改变,以此定量仿真出轮廓的受力形变;最后将曲线拼接起来构成物体的整体形变模型。文中讨论了常见的方体和板块体在挤压、拉伸和扭转这三种非常普遍受力下的形变特性,并使用多曲线拟合方法建立了形变模型。多曲线拟合方法虽然在表现精度上存在一定误差,但建模形式简单、计算速度快,为仿真中表现速度与表达精度的矛盾提供了一种有效的解决手段。     

基于ADAMS二次开发软件的星箭分离分析平台研究

基于ADAMS二次开发软件的星箭分离分析平台是适用于星箭分离系统设计中分离分析的软件,可验证分离方案的合理性及可行性。分离分析平台具有建立分离结构的功能,在标称仿真、极限仿真以及蒙特卡洛仿真三种状态下,以曲线和列表的形式计算并输出各个分离体的角速度、角度、速度、位移,分离体之间的相对速度、相对位移、最小间隙等。该分离分析平台具备通用性和规范性,实现了分离仿真中模型的参数化和智能化设计,达到了快速反映分离参数状态变化的目的。     

Skeleton-based intrinsic symmetry detection on point clouds

We present a skeleton-based algorithm for intrinsic symmetry detection on imperfect 3D point cloud data. The data imperfections such as noise and incompleteness make it difficult to reliably compute geodesic distances, which play essential roles in existing intrinsic symmetry detection algorithms. In this paper, we leverage recent advances in curve skeleton extraction from point clouds for symmetry detection. Our method exploits the properties of curve skeletons, such as homotopy to the input shape, approximate isometry-invariance, and skeleton-to-surface mapping, for the detection task. Starting from a curve skeleton extracted from an input point cloud, we first compute symmetry electors, each of which is composed of a set of skeleton node pairs pruned with a cascade of symmetry filters. The electors are used to vote for symmetric node pairs indicating the symmetry map on the skeleton. A symmetry correspondence matrix (SCM) is constructed for the input point cloud through transferring the symmetry map from skeleton to point cloud. The final symmetry regions on the point cloud are detected via spectral analysis over the SCM. Experiments on raw point clouds, captured by a 3D scanner or the Microsoft Kinect, demonstrate the robustness of our algorithm. We also apply our method to repair incomplete scans based on the detected intrinsic symmetries.     

Performance modeling and analysis of message-oriented event-driven systems

Message-oriented event-driven systems are becoming increasingly ubiquitous in many industry domains including telecommunications, transportation and supply chain management. Applications in these areas typically have stringent requirements for performance and scalability. To guarantee adequate quality-of-service, systems must be subjected to a rigorous performance and scalability analysis before they are put into production. In this paper, we present a comprehensive modeling methodology for message-oriented event-driven systems in the context of a case study of a representative application in the supply chain management domain. The methodology, which is based on queueing Petri nets, provides a basis for performance analysis and capacity planning. We study a deployment of the SPECjms2007 standard benchmark on a leading commercial middleware platform. A detailed system model is built in a step-by-step fashion and then used to predict the system performance under various workload and configuration scenarios. After the case study, we present a set of generic performance modeling patterns that can be used as building blocks when modeling message-oriented event-driven systems. The results demonstrate the effectiveness, practicality and accuracy of the proposed modeling and prediction approach.     

通用型无线数据监测模型设计

针对现有无线数据监测方案大多基于各专业领域,数据需求、处理方法和安全标准各异,开发应用成本较高等问题,提出了一种通用型无线数据监测模型设计方案,介绍了模型的总体设计及关键技术实现。该模型采用STC89C52RC作为主控芯片;采用通用集成型无线传输模块,通过射频芯片nRF24L01实现数据的发射和接收;总线模块采用RS232串口数据通信方式。测试结果显示,该模型中现场节点数据监测模块功率为8.58mW,区域数据集中模块功率为29.7mW,模型收发距离大于30m,能够完成可靠、稳定的无线数据通信。     

城市雨水利用技术体系构建研究

结合城市降雨与径流特点和下垫面特点,从城市降雨径流的产生、地面与管网的汇流、河道的行洪与调节和城乡之间的上下游区域关系与应用条件等多方面综合考虑,构建小区、城市河湖、城乡联调3个层面的城市雨水利用技术体系框架,为城市雨水科学、合理的利用提供参考和借鉴。     

贵州卵砾石土地基承载力的分析与研究

为满足建筑物自身的要求,根据贵州省地质地貌的特点,结合工程地质勘察的资料,分析贵州卵砾石土的一般特征及力学性质,研究贵州卵砾石土的地基承载力,评价贵州典型卵砾石的承载性能及其工程地质特性,为选择卵砾石土作为建筑物地基提供参考依据。