基于变胞原理的变自由度机构拓扑型分析

变自由度机构是一类具有特殊用途的机构。根据自由度的变化规律对变自由度机构进行了分类;利用变胞机构原理和拓扑理论对变自由度机构自由度的变化过程进行了构态变换描述。提出了一种对不同类型的变自由度机构进行拓扑型分析的“杆-杆”合并的新方法,由于把机构的型分析问题转化为矩阵计算,该方法可推广应用于更复杂的问题,并有利于在计算机上进行机构型分析。通过实例对该方法进行了验证。     

物流服务供应链模式特性及其绩效评价研究

在深入分析物流服务供应链模式特性的基础上,提出了基于供应链的物流服务模式模型,并从运行域、层次域、构成域三个属性域给出了评价物流服务供应链模式的指标体系,最后利用熵技术和层次分析法对该模式进行了绩效评价。     

多目标的供应链集成优化及数值仿真

针对供应链设计中的供应链优化这个关键问题,建立了一个多目标的供应链集成优化模型。该模型将供应链三个层次的优化内容集成在一起进行优化,采用成本、柔性、客户服务水平以及向用户承诺的产品交付时间四个度量指标。针对多目标优化模型,提出了一种改进的多群体遗传算法。最后,利用一个具体实例进行了数值仿真。     

可重构制造系统建模方法

对可重构制造系统建模方法,包括基于Petri网的可重构制造系统建模、基于排队网络的可重构制造系统建模、基于马尔可夫链的可重构制造系统建模、基于多Agent理论的可重构制造系统建模等方法的研究现状进行了系统的介绍,并进行了分析和比较,最后给出了可重构制造系统建模的发展方向。     

A TPDP-MPM-based approach to understanding the evolution mechanism of landslide-induced disaster chain

With complex topographic and hydrological characteristics, the landslide-induced surge disaster chain readily develops in mountainous and gorge areas, posing a huge challenge for infrastructure construction. This landslide-induced surge disaster chain involves a complex fluid-solid coupling between the landslide mass and a water body and exhibits complex energy conversion and dissipation characteristics, which is challenging to deal with using traditional finite element analysis. In this study, the energy evolution characteristics in the whole process of the disaster chain were first investigated, and the momentum-conservation equations for different stages were established. Then, the two-phase double-point material point method (TPDP-MPM) was used to model the landslide-induced surge disaster chain, and an experiment involving block-induced surge was modeled and simulated to validate this method. Finally, three generalized models were established for the landslide-induced surge process in a U-shaped valley, including subaerial, partly submerged, and submarine scenarios. The interaction mechanism between the landslide mass and the water body in the disaster chain was revealed by defining the system energy conversion ratio and the mechanism of evolution of the disaster chain from the perspective of energy. The results help further evaluate the secondary disasters, given the submerged position of the landslide mass.     

连续箱梁挂篮施工监理要点初探

通过连续箱梁挂篮施工监理全过程论述,分析了连续箱梁挂篮施工监理中的要点及难点,并结合实践叙述了连续箱梁挂篮施工控制要点,供同行参考。     

斜置安装挂篮施工工艺总结

结合西汉高速公路47合同段金水河特大桥实例,详细介绍三角挂篮安装的几种工艺,同时提出斜置安装挂篮的施工方案,为同类型桥的三角挂篮安装提供借鉴经验。     

精益建筑供应链下建筑企业核心竞争力分析

精益建筑供应链管理是一种新的建设项目管理模式,该模式对建筑企业核心竞争力的构建起到促进作用。文章分析了精益建筑供应链模式下建筑企业核心竞争力,指出了该模式能使建筑企业更好管理建设工程,能使企业在工程项目质量、工期和成本方面获得相应的核心竞争力。提出了在精益建筑供应链下建筑企业核心竞争力的构建要点。     

液化天然气产业链安全技术研究

针对液化天然气易燃、易爆、低温等特性以及产业链长的特征,介绍了产业链各环节、各类用户的安全技术特点与要求,论述了LNG泄漏引发的安全风险及防范措施,提出了实施全面安全管理的建议。     

Current condition and future directions for lean construction in highways projects: A small and medium-sized enterprises (SMEs) perspective

The aim of this study is to identify the parameters defining how Lean Construction (LC) is being implemented (current condition) and how LC can be further promoted (future direction) from a Small-Medium Sized Enterprises (SMEs) perspective. Although SMEs constitute the largest group in construction supply chains, LC, as an emerging phenomenon in civil construction project management, has been rarely investigated from an SMEs perspective. Also, overlooking the more macro factors like project governance and supply chain management, LC deployments have been mainly discussed from a production process perspective to date. After a review of the extant literature and 20 interviews with managers from the highways sector, a list of 31 current condition and 40 future direction statements were produced, classified under the delivery, process, training, project governance and supply chain related headings and used in a questionnaire survey with 110 responses. The current condition highlights problems like a short-term relations structure, competitive tendering mechanisms, fragmentation, problems in engaging with SMEs for LC, unstandardised LC techniques, and issues with convincing SMEs to deploy LC by demonstrating the business case on mutual benefits. Action items relating to the current project delivery structure were given the highest importance by the supply chain, alongside the LC training and project governance issues for the future of LC at highways SMEs. Additionally, a statistically significant correlation was identified among many future action items.