南方山区风电场场内道路优化设计探讨

针对南方山区风电自然地形与地质条件的特点,本文论述了选择特种运输车辆及便捷经济的运输方案,部分路段采用道路的技术参数的极限值,并通过平面选线多方案比较,达到减少道路的土石方工程量降低工程造价的目的.     

机械零件加工路线的影响因素研究

针对机械零件的特点,分析了机械零件不同特征的加工方法,实现了零件特征要素加工方法,研究了零件一次装夹的优化、决策和工步排序,最终得到了机械零件在加工中心上的最优工艺路线。     

既有建筑拆除物碎砖类骨料再生混凝土的可行性研究

文章介绍了利用既有建筑拆除物碎砖作为骨料,制备再生混凝土的研究背景及目的,并对既有建筑拆除物中的碎砖作为骨料,制备再生混凝土的研究内容、步骤、技术路线等方面做了可行性研究。     

IXIA单端口百万级BGP随机路由测试解决方案

随着网络IP化进程的推进,核心网路由器间交互的路由条目每年都在成倍增长,总数已经接近百万。如何判断路由器是否有能力承载那么巨大的路由容量,如何测试它的转发能力,以及当主备倒换发生时,能多快地完成业务的收敛,一直是路由器BGP协议性能测试的瓶颈。IXIA作为顶级的测试设备厂商,一直致力于提供超高性能的硬件解决方案。我们在路由器测试领域以超高的端口能力,提供客户单端口、百万级BGP路由测试解决方案。该方案可以提供对现网路由的测试,也可根据现网路由扩展大量的随机路由,从而在最大强度、最接近真实网络的情况下,挑战被测设备的路由处理能力,同时提供硬件级的收敛测试方案。这相比于传统软件后分析的收敛测试,测试精度得到了大幅提高。     

城市群旅客协同运输线路边际效益分析及优选

为适应城市群旅客出行需求并实现系统整体效益的最大化,提出基于边际效益理论的城市群协同范围及协同线路优化选择问题。基于超网络理论构建城市群多方式交通系统的超网络模型,考虑客流关联强度和换乘设施等因素生成协同线路备选集;将超网络的路径分为在乘段与换乘段,提出多方式出行路径的广义出行费用计算方法;利用3层巢式Logit模型构建旅客城市群出行路径选择行为。在此基础上,提出以系统效益最大化为优化目标的双层规划模型,采用遗传算法和相继平均法求解上下层模型,并基于边际效益递减理论确定协同运输范围及协同线路。最后以京津冀城市群为例对模型构建的合理性进行验证并应用于问题分析。结果表明：协同运输线路的规模存在边际效益且优选出的协同线路能够基本满足京津冀城市群旅客出行需求,以线路为导向的多方式联运模式拓展了联程运输模式,为城市群多模式协同运输的实施提供了途径。     

无线传感网移动数据收集路径规划算法

针对无线传感网中能源高效的实时数据收集问题,提出了包含节点聚簇、路径规划、合并路径和数据收集4个阶段的移动数据收集协议和节省开销及近邻2个启发式路径规划算法,构建了满足时延且移动开销最小的数据收集路径.仿真结果表明,提出的路径规划算法在节约网络能耗、保证时延要求和减少移动开销等方面都更具优势.     

Synthesis of magnesium aluminate spinel—An overview

Magnesium aluminate spinel (MAS) is a remarkable ceramic material known for its unique combination of beneficial properties. But due to volume expansion associated with spinel formation, and the high cost of production, MAS was not commercially successful till last century. However, environmental friendliness and superior properties have helped MAS to substitute magnesia-chrome refractories and are commercially acceptable with time. From an industrial perspective, solid-oxide reaction route or conventional oxide mixing route is the most popular method used for the synthesis of MAS. Although there have been myriad other common routes-coprecipitation, sol–gel, auto-ignition, molten technique, and so forth to produce spinel, solid-oxide reaction route is still the principal route from the industrial point of view owing to its ease of bulk production and low cost of production for refractory applications. This report attempts to accumulate the information on different synthesis techniques used for the synthesis of MAS for easy and ready reckoning.     

Transition Metal Phosphide Nanoarchitectonics for Versatile Organic Catalysis

Transition metal phosphides (TMP) posses unique physiochemical, geometrical, and electronic properties, which can be exploited for different catalytic applications, such as photocatalysis, electrocatalysis, organic catalysis, etc. Among others, the use of TMP for organic catalysis is less explored and still facing many complex challenges, which necessitate the development of sustainable catalytic reaction protocols demonstrating high selectivity and yield of the desired molecules of high significance. In this regard, the controlled synthesis of TMP-based catalysts and thorough investigations of underlying reaction mechanisms can provide deeper insights toward practical achievement of desired applications. This review aims at providing a comprehensive analysis on the recent advancements in the synthetic strategies for the tailored and tunable engineering of structural, geometrical, and electronic properties of TMP. In addition, their unprecedented catalytic potential toward different organic transformation reactions is succinctly summarized and critically analyzed. Finally, a rational perspective on future opportunities and challenges in the emerging field of organic catalysis is provided. On the account of the recent achievements accomplished in organic synthesis using TMP, it is highly anticipated that the use of TMP combined with advanced innovative technologies and methodologies can pave the way toward large scale realization of organic catalysis.     

Synthesis and optimization strategies of nanostructured metal oxides for chemiresistive methanol sensors

Thanks to the merits such as high specific surface areas, superior electronic conduction and unique gas diffusion path derived from the nanoscales, the demand for detecting methanol has contributed to the rapid expansion of gas sensors based on metal oxide nanostructures. In this review, the “process-structure-performance” correlations of metal oxide nanostructures utilized in the detection of methanol are analyzed. The sensing mechanisms of nanostructured metal oxides operated at different temperatures for methanol monitoring are first introduced. Subsequently, various synthesis processes (e.g. hydrothermal, sol-gel and electrospinning) utilized to modulate the structure and morphology of metal oxide nanostructures are discussed. Given the limitations that existed in methanol gas sensors, numerous optimization strategies including doping, surface modifications, newly designed structures and morphologies, the self-doping defects are enumerated to dramatically enhance the sensing properties represented by the improvement of sensitivity, the reduction of working temperature, the decrease of detection limit, etc. Additionally, the challenges and future research directions of advanced methanol sensors based on metal oxide nanostructures are proposed. It is ultimately expected that this review will help break the bottleneck of nanostructured metal oxides gas sensors in the field of methanol detection, and further promote the actual application of chemiresistive methanol sensors.