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

服务质量要素体系的探讨

The study explored consumers' evaluation factor system and the zone of tolerance in the service quality, and the impact on consumer behavior in two branches of trade: the shopping center and the architectural material corporation, with the method of questionnaire survey. The main conclusions are as following: 1) The basic factors on service quality of shopping center are five, such as assurance、tangibles、the services of the post-selling、convenience and reliability. 2) There are also five factors on service quality of the architectural material corporation, such as the supplying of the products, the abilities of the salesmen, courtesy, package and the information. 3) The zones of tolerance of the factors in service quality are difference. In some way, they reflect the importance of the factors. 4) the service quality and its factors have positive impacts on the consumer behaviors. 5) In the branch of glass producing in our country, the service quality of a corporation is significant below the ideal level, even if it is a good one which the consumers expressed positive purchase intention on the corporate. The service quality of the coporate on which the consumers expressed uncertain purchase intention, is in nearby of the minimum acceptable level.

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.

Curriculum: directions, decisions and debate.

The purpose of this paper is to provide an overview of the factors which may effect, stimulate or be the cause of curriculum changes in higher education (HE) in Scotland. This overview leads to a series of questions which could be used to encourage debate within and across institutions on strategic developments, which may enhance and inform the development of and support for the curriculum. The paper will begin by offering a definition of the term 'curriculum' before identifying the current areas of influence on how the curriculum, in its broadest sense, is shaped and delivered. This paper will provide an outline of some of the different approaches to the design and delivery of the curriculum which enhance the student experience in Scottish higher education, but which will of course have a wider relevance to HE in the UK and perhaps beyond.

A avaliação da qualidade dos serviços em organizadores de feiras

Dissertação de Mestrado apresentada à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências da Comunicação, especialização em Marketing e Publicidade.

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.

Safe Compositional Specification of Networking Systems: TRAFFIC The Language and Its Type Checking

This paper formally defines the operational semantic for TRAFFIC, a specification language for flow composition applications proposed in BUCS-TR-2005-014, and presents a type system based on desired safety assurance. We provide proofs on reduction (weak-confluence, strong-normalization and unique normal form), on soundness and completeness of type system with respect to reduction, and on equivalence classes of flow specifications. Finally, we provide a pseudo-code listing of a syntax-directed type checking algorithm implementing rules of the type system capable of inferring the type of a closed flow specification.

Building effectiveness communication ratios (BECs): an integrated ‘life-cycle’ methodology for mitigating energy-use in buildings

Current building regulations are generally prescriptive in nature. It is widely accepted in Europe that this form of building regulation is stifling technological innovation and leading to inadequate energy efficiency in the building stock. This has increased the motivation to move design practices towards a more ‘performance-based’ model in order to mitigate inflated levels of energy-use consumed by the building stock. A performance based model assesses the interaction of all building elements and the resulting impact on holistic building energy-use. However, this is a nebulous task due to building energy-use being affected by a myriad of heterogeneous agents. Accordingly, it is imperative that appropriate methods, tools and technologies are employed for energy prediction, measurement and evaluation throughout the project’s life cycle. This research also considers that it is imperative that the data is universally accessible by all stakeholders. The use of a centrally based product model for exchange of building information is explored. This research describes the development and implementation of a new building energy-use performance assessment methodology. Termed the Building Effectiveness Communications ratios (BECs) methodology, this performance-based framework is capable of translating complex definitions of sustainability for energy efficiency and depicting universally understandable views at all stage of the Building Life Cycle (BLC) to the project’s stakeholders. The enabling yardsticks of building energy-use performance, termed Ir and Pr, provide continuous design and operations feedback in order to aid the building’s decision makers. Utilised effectively, the methodology is capable of delivering quality assurance throughout the BLC by providing project teams with quantitative measurement of energy efficiency. Armed with these superior enabling tools for project stakeholder communication, it is envisaged that project teams will be better placed to augment a knowledge base and generate more efficient additions to the building stock.

Tropospheric aerosol detection over Southern Ireland using a backscatter Raman lidar

Lidar is an optical remote sensing instrument that can measure atmospheric parameters. A Raman lidar instrument (UCLID) was established at University College Cork to contribute to the European lidar network, EARLINET. System performance tests were carried out to ensure strict data quality assurance for submission to the EARLINET database. Procedures include: overlap correction, telecover test, Rayleigh test and zero bin test. Raman backscatter coefficients, extinction coefficients and lidar ratio were measured from April 2010 to May 2011 and February 2012 to June 2012. Statistical analysis of the profiles over these periods provided new information about the typical atmospheric scenarios over Southern Ireland in terms of aerosol load in the lower troposphere, the planetary boundary layer (PBL) height, aerosol optical density (AOD) at 532 nm and lidar ratio values. The arithmetic average of the PBL height was found to be 608 ± 138 m with a median of 615 m, while average AOD at 532 nm for clean marine air masses was 0.119 ± 0.023 and for polluted air masses was 0.170 ± 0.036. The lidar ratio showed a seasonal dependence with lower values found in winter and autumn (20 ± 5 sr) and higher during spring and winter (30 ± 12 sr). Detection of volcanic particles from the eruption of the volcano Eyjafjallajökull in Iceland was measured between 21 April and 7 May 2010. The backscatter coefficient of the ash layer varied between 2.5 Mm-1sr-1 and 3.5 Mm-1sr-1, and estimation of the AOD at 532 nm was found to be between 0.090 and 0.215. Several aerosol loads due to Saharan dust particles were detected in Spring 2011 and 2012. Lidar ratio of the dust layers were determine to be between 45 and 77 sr and AOD at 532 nm during the dust events range between 0.84 to 0.494.

Development and assessment of new sensor systems in food packaging applications

The use of optical sensor technology for non-invasive determination of key quality pack parameters improved package/product quality. This technology can be used for optimization of packaging processes, improvement of product shelf-life and maintenance of quality. In recent years, there has been a major focus on O2 and CO2 sensor development as these are key gases used in modified atmosphere packaging (MAP) of food. The first and second experimental chapters (chapter 2 and 3) describe the development of O2, pH and CO2 solid state sensors and its (potential) use for food packaging applications. A dual-analyte sensor for dissolved O2 and pH with one bi-functional reporter dye (meso-substituted Pd- or Ptporphyrin) embedded in plasticized PVC membrane was developed in chapter 2. The developed CO2 sensor in chapter 3 was comprised of a phosphorescent reporter dye Pt(II)- tetrakis(pentafluorophenyl) porphyrin (PtTFPP) and a colourimetric pH indicator α-naphtholphthalein (NP) incorporated in a plastic matrix together with a phase transfer agent tetraoctyl- or cetyltrimethylammonium hydroxide (TOA-OH or CTA-OH). The third experimental chapter, chapter 4, described the development of liquid O2 sensors for rapid microbiological determination which are important for improvement and assurance of food safety systems. This automated screening assay produced characteristic profiles with a sharp increase in fluorescence above the baseline level at a certain threshold time (TT) which can be correlated with their initial microbial load and was applied to various raw fish and horticultural samples. Chapter 5, the fourth experimental chapter, reported upon the successful application of developed O2 and CO2 sensors for quality assessment of MAP mushrooms during storage for 7 days at 4°C.