Syntheses, crystal structures and magnetic properties of two heterometallic coordination polymers

Two heterometallic chain coordination polymers with the chemical formula {[Cu2Mn2L2(CH3OH)(H2O)] center dot 0.5CH(3)OH center dot 0.5CH(3)CH(2)OH}(n) (1) and {[Cu2Co2L2(H2O)(2)] center dot H2O}(n) (2) have been synthesized and characterized by IR, UV spectroscopy and single-crystal X-ray structural analysis, where H4L = 2-hydroxy-3-[(E)-({2-[(2-hydroxybetizoyl)amino]ethyl}imino)methyl] benzoic acid. Magnetic measurements showed that the two compounds exhibit antiferromagnetic coupling exchange interactions, and satisfactory fittings to the observed magnetic susceptibility data were obtained by assuming a linear four-spin arrangement with two isotropic magnetic exchange interactions.

Synthesis, crystal structure and magnetic properties of a chain coordination polymer {[Cu4L2(H2O)] center dot H2O}(n)

A chain coordination polymer with the chemical formula {[Cu4L2(H2O)] (.) H2O)(n), has been synthesized by the assembly reaction of K(2)CuL(.)1.5H(2)O and Cu(OAC)(2)(H2O)-H-. with a 1:1 mole ratio in methanol., where H4L=2-hydroxy-3-[(E)-({2-[(2-hydroxybenzoyl)imino]ethyl I imino)methyl] benzoic acid, OAC(-) = CH3COO-. The crystal structure was determined by single-crystal X-ray diffraction analysis, the compound has chain molecular structure formed by dissymmetrical tetranuclear units. The magnetic measurements showed that Cu-Cu of the complex exhibit antiferromagnetic interactions, and satisfactory fittings to the observed magnetic susceptibility data were obtained by assuming a binuclear system, and further using molecular field approximation to deal with magnetic exchange interactions between binuclear systems.

质子交换膜燃料电池在无缆水下机器人上的应用研究

质子交换膜燃料电池(PEMFC)作为一种新兴的能源,在汽车和航天器上已经获得成功的应用,本文针对水下环境和PEMFC的特点,对PEMFC在无缆水下机器人(UUV)上试验应用的关键技术进行讨论.

一种柔性冲压自动化生产线系统的研制

本文介绍了一种用于大型汽车覆盖件冲压生产的柔性自动化生产线，系统由６台压机、１２台上下料机械手、１台翻转传输装置、４台穿梭传输装置及１台磁力分层装置构成．给出了生产线的主要性能指标、机械手结构简图及单元控制系统框图，简要介绍了系统的工作原理。

变速箱试验环线集成控制系统

研究当前国内外变速箱试验系统的特点,基于现代汽车变速箱生产信息化、网络化和柔性化的要求,依托某变速箱装配线项目,针对其试验环线,提出一种具有并行结构的变速箱自动试验环线,并设计基于Device Net的控制系统,探究试验环线的智能控制。该系统已经进入实际应用,可较好地完成变速箱的性能检测以及试验后的数据分析。

基于数字化生产模型的在线故障诊断技术研究

提出了一种基于数字化的生产模型,使用控制图、故障树分析和专家知识,能够进行制造过程实时监控的诊断,该模型提高了故障诊断系统的可靠性,并提供了可实际操作的可视化建模工具。所开发的在线统计过程控制系统能够根据生产事件的监测,动态响应制造过程变化。该系统运用可视化建模工具,根据专家经验进行故障树建模,通过故障树自动生成专家系统诊断规则库,实现诊断知识的自动获取。将该系统应用于汽车变速箱装配过程的检测与故障诊断,验证了方法的有效性。

一种基于多特征融合的汽车变速箱螺栓在线视觉检测系统

本文根据汽车变速箱装配线螺栓检测的要求,结合检测现场的实际图像特点,采用融合灰度投影与颜色直方图两种特征的方法,利用相似性测度的计算方法,设计了一种变速箱螺栓在线装配质量检测系统,该系统用于实现螺栓的的缺失及漏拧检测,试验结果表明,方法具有良好的实用性,取得了比较理想的效果。

基于RFID的混流装配汽车生产线物料动态配送研究

针对混流装配的汽车自动化生产线提出了基于RFID的车辆追踪和基于条码的无线物料库存管理实现方法。在此基础上,设计了装配生产线的物料动态配送调度业务流程,给出了物料动态配送的规划依据,并进行了实例计算。

汽车变速箱性能检测系统设计与实现

本文从整体上论述了汽车变速箱性能检测系统的测试原理和设计方案,并从硬件和软件两方面详细阐述了汽车变速箱性能检测系统的组成。现场总线的采用,使本系统的结构更加简单,实施更加方便。实践证明,该方法是可行的,可靠的。

面向汽车变速器状态监测的虚拟仪器系统研究

摘要 变速器是汽车主要部件之一，其质量直接影响整车的性能和质量。对装配后的变速器进行下线检测是生产过程必需的步骤。目前我国汽车变速器的下线检测多数在变速器试验台上进行，由工人耳听变速器的振动噪声判断其是否合格。人工判断的方法存在精度低、随机性高和受工人经验、情绪影响大等缺点。因此，实现变速器状态监测的自动化，研究一种适用于汽车变速器下线检测的状态监测系统具有很大的现实意义。 虚拟仪器技术构建方式快速灵活、人机界面友好、具有强大的信号处理能力，而且可以充分利用变速器试验台已有的工控机平台。本论文研究开发了一套面向汽车变速器状态监测的虚拟仪器系统。 第一章介绍了课题来源和研究目的；综述了虚拟仪器的发展和变速器状态监测与故障诊断的研究现状。 第二章分析了面向振动信号的常用信号处理方法及其不足、介绍了时域同步平均和基于重采样的阶次分析方法，典型齿轮故障的时频域特征。 第三章根据变速器状态监测的要求设计并实现了状态监测的硬件系统，主要包括传感器、数据采集卡。 第四章开发了基于虚拟仪器的软件系统，完成了参数设置模块、数据采集模块、信号预处理模块、时域分析模块、频域分析模块、时域同步平均模块、阶次分析模块、文件管理模块和网络通信模块的具体设计，并将这些模块在主程序的程序框图中按照一定的逻辑关系组合起来，形成一个完整的变速器状态监测系统。 第五章对本文工作做了总结并对以后工作进行了展望

Design and analysis of kinetic energy recovery system for automobiles: a case study for commuters in Edinburgh.

Transport and its energetic and environmental impacts affect our daily lives. The transport sector is the backbone of the United Kingdom’s economy with 2.3 million people being employed in this sector. With a high dependency on transport for passengers and freight and with the knowledge that oil reserves are rapidly decreasing a solution has to be identified for conserving fuel. Passenger vehicles account for 61% of the transport fuel consumed in the U.K. and should be seen as a key area to tackle. Despite the introduction and development of electric powered cars, the widespread infrastructure that is required is not in place and has attributed to their slow uptake, as well as the fact that the electric car’s performance is not yet comparable with the conventional internal combustion engine. The benefits of the introduction of kinetic energy recovery systems to be used in conjunction with internal combustion engines and designed such that the system could easily be fitted into future passenger vehicles are examined. In this article, a review of automobile kinetic energy recovery system is presented. It has been argued that the ultracapacitor technology offers a sustainable solution. An optimum design for the urban driving cycle experienced in the city of Edinburgh has been introduced. The potential for fuel savings is also presented

Sustainable urban transport in Central America - a future without the car?

Is it conceivable to contemplate a future without the car as the center of an urban transportation system? Can emerging economies grow without concomitant growth in car usage? San Pedro Sula, Honduras, is one city at a critical decision point about the future of transportation and mobility. Will it be a sustainable transport future that balances economic, environmental and social needs or will it be the traditional “predict and provide” approach that attempts to expand the capacity of the road system to meet future travel demand. This paper provides some background into the issue for this Central American city by describing the current urban transport system, current plans for improvement and outlines a process for defining a vision for a sustainable transport future in San Pedro Sula. The paper concludes with a challenge to all cities that currently have low automobile ownership rates to consider a sustainable transport system in order to “thrive” with transport choices for all residents rather than “choke” on congestion and the negative side effects thereof.

The Jesus Chapel in St Paul's Cathedral, London: a reconstruction of its appearance before the Reformation

New, Elizabeth, 'The Jesus Chapel in St Paul's Cathedral, London: a reconstruction of its appearance before the Reformation', Antiquaries Journal (2005) 85, pp.103-124 RAE2008

Segmenting Foreground Objects from a Dynamic Textured Background via a Robust Kalman Filter

The algorithm presented in this paper aims to segment the foreground objects in video (e.g., people) given time-varying, textured backgrounds. Examples of time-varying backgrounds include waves on water, clouds moving, trees waving in the wind, automobile traffic, moving crowds, escalators, etc. We have developed a novel foreground-background segmentation algorithm that explicitly accounts for the non-stationary nature and clutter-like appearance of many dynamic textures. The dynamic texture is modeled by an Autoregressive Moving Average Model (ARMA). A robust Kalman filter algorithm iteratively estimates the intrinsic appearance of the dynamic texture, as well as the regions of the foreground objects. Preliminary experiments with this method have demonstrated promising results.

On trip planning queries in spatial databases

In this paper we discuss a new type of query in Spatial Databases, called Trip Planning Query (TPQ). Given a set of points P in space, where each point belongs to a category, and given two points s and e, TPQ asks for the best trip that starts at s, passes through exactly one point from each category, and ends at e. An example of a TPQ is when a user wants to visit a set of different places and at the same time minimize the total travelling cost, e.g. what is the shortest travelling plan for me to visit an automobile shop, a CVS pharmacy outlet, and a Best Buy shop along my trip from A to B? The trip planning query is an extension of the well-known TSP problem and therefore is NP-hard. The difficulty of this query lies in the existence of multiple choices for each category. In this paper, we first study fast approximation algorithms for the trip planning query in a metric space, assuming that the data set fits in main memory, and give the theory analysis of their approximation bounds. Then, the trip planning query is examined for data sets that do not fit in main memory and must be stored on disk. For the disk-resident data, we consider two cases. In one case, we assume that the points are located in Euclidean space and indexed with an Rtree. In the other case, we consider the problem of points that lie on the edges of a spatial network (e.g. road network) and the distance between two points is defined using the shortest distance over the network. Finally, we give an experimental evaluation of the proposed algorithms using synthetic data sets generated on real road networks.