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One standard to rule them all? : descriptive choices for open education
No full textDrawing on our experience of supporting a nationwide Open Educational Resources programme (the UKOER programme), this presentation will consider the diverse range of approaches to describing OERs that have emerged across the programme and their impact on resource sharing, workflows, and an aggregate view of the resources. Due to the diverse nature of the projects in the programme, ranging from individual educators to discipline-based consortia and institutions, it was apparent that no one technical or descriptive solution would fit all. Consequently projects were mandated to supply only a limited amount of descriptive information (programme tag, author, title, date, url, file format, file size, rights) with some additional information suggested (language, subject classifications, keywords, tags, comments, description). Projects were free to choose how this information should be encoded (if at all), stored, and shared. In response, the projects have taken many different approaches to the description and management of resources. These range from using traditional highly structured and detailed metadata standards to approaches using whatever descriptions are supported by particular web2.0 applications. This experimental approach to resource description offers the wider OER community an opportunity to examine and assess the implications of different strategies for resource description and management This paper illustrates a number of examples of projects' approaches to description, noting the workflows and effort involved. We will consider the relationship of the choice of tool (repository, web2.0 application, VLE) to the choice of standards; and the relationship between local requirements and those of the wider community. We will consider the impact of those choices on the dissemination and discoverability of resources. For example, the implications of resource description choices for discovery services which draw on multiple sources of OERs
Evaluation of an InP Mach-Zehnder modulator for high speed optical network system architectures and emerging photonically integrated optical modules
No full textThe realization of an Indium Phosphide material based Multi Quantum Well Mach-Zehnder modulator (InP MZ) provides many advantages compared to other contemporary optical modulator technologies available. Utilizing the Quantum Confined Stark Effect (QCSE) in a semiconductor Multi Quantum Well (MQW) it enables a small physical size modulator to be realized with comparatively low drive voltage and low power consumption. The development of a equivalent InP MZ model enables optical systems performance to be simulated and is a very important tool for system architects as part of a technology evaluation activity, enabling the performance of an optical component incorporating the InP MZ to be evaluated and overall systems performance and ultimate network topology to be quantified prior to committing financial expense and other resources. This paper discusses the realization of the model following a detailed analysis of the InP MZ modulator characteristics. A comparison of the simulated versus practical results of a fabricated InP MZ is presented
L. Gardner and Sons Limited: the history of a British industrial firm. A study with special reference to markets, workplace industrial relations, and manufacturing engineering technology, 1955-1986
No full textInvestigating a range of commonly asserted characteristics relating to British family firms, this study concluded that, although they retained ownership and control and did not adopt mass-production, no persuasive evidence was found to suggest that the family managers of L. Gardner and Sons behaved unprofessionally or irrationally during the first eighty-seven years of the firm?s existence.Analysed from the perspective of markets and workplace industrial relations, it was found that the Gardner family managers coped reasonably well with most of the macroenvironmental shifts that occurred between 1955 and 1975. However, two serious errors were made: the first, which caused a short-term loss of revenue and a long-term loss of market leadership, was a result of negligence, the second stemmed from an outdated authoritarian approach to industrial relations that resulted in intense discord in the workplace, alleviated only after the management was replaced by a more astute and enlightened regime.A third error occurred after Gardner was sold to Hawker Siddeley, a large British industrial group, in 1977. Based on a perception that Gardner's plant was outdated, the new owners invested in expensive computer controlled manufacturing systems, and increased the volume of subcontracted components, strategies that caused disruptions to production schedules, eroded quality standards, and failed to improve output. As a result, Gardner's superlative reputation for reliability and service became tarnished and its market share plummeted. In 1986, when mounting trading losses became unacceptable, the firm was sold-on to a competitor and production effectively ceased.This thesis asserts that, as a family firm, Gardner traded profitably and provided incomes for thousands of employees for more than a century. Moreover, the sale to Hawker Siddeley conferred wealth on the family shareholders and financial security on their descendents. Gardner was not therefore, a failure either between 1898 and 1955, or before 1978
Numerical and analytical modelling of multi-layer adhesive-film interface systems
No full textThis paper reports the use of Finite Element Modelling (FEM) simulations of the through-thickness Young?s and shear moduli of alternating film-adhesive multi-layer interface materials. The FEM results were compared with analytical modified Rule of Mixtures (RoM) predictions. Two representative adhesives ('low' and 'high' Young's moduli, with respect to the film Young's modulus) were used in combination with both conventional and auxetic films. Enhancements in the Young's modulus and shear modulus of the interface were predicted for the low modulus adhesive systems for both conventional and auxetic films. The auxetic film-low modulus adhesive systems showed enhancements by at least a factor of 2 in the through-thickness mechanical properties compared to the conventional film-low modulus adhesive systems. Of the high modulus adhesive systems, only the auxetic film system showed enhancements in through-thickness mechanical properties. The conventional film-high modulus adhesive systems showed a decrease in the through-thickness Young's and shear moduli
A New Approach on Spatio-temporal Scene Analysis for Driver Observation
No full textAdvanced Driver Assistance Systems are, due to their potentials regarding security and markets, in the focus of future developments within the automotive industry. The Visual observation of the car interior is gaining attention due to the increasing efficiency of methods and technologies in digital image processing. Special weight is put on the visual driver observation, which measures diversion and fatigue of the driver and notifies about endangering behavior. This is accomplished by utilizing complex image-processing systems. The spatial positions and orientations of head and eyes are measured and evaluated. This report presents in detail and coherently the motivation and the current status of available approaches and systems. Following, a new concept for spatio-temporal modeling and tracking of partially rigid objects is developed and described. This concept is based on methods for spatio-temporal scene analysis, graph theory, adaptive information fusion and multi-hypothesis tracking. Our original contributions are the detailed representation of the available procedure.,; and systems in this certain field and the development of a new concept and related prototypes
A General Modular Design Methodology for Flexible Smart Grid Inverters
No full textAt present, power supply systems all over the world are facing challenging situations where they have to be extremely flexible, reliable and expandable. Due to the growing proportion of distributed and renewable energy sources, existing grids have to be revised. Power electronic inverters are the grid interfaces for energy converting systems and a key component to control and manage the energy systems operation. To fulfill the requirements for tomorrow's energy systems, new concepts for flexible and adaptable inverter design are needed. In this paper an innovative concept for future oriented power system integration - the modular inverter design - is presented for three phase inverters. The introduced concept offers the required flexibility and adaptability for modern power supply systems. Modularity supports fast and simple custornization, while all inverter components still can be manufactured in mass production. Using up-to-date technologies and the introduced advanced inverter concept; modular, flexible, reliable and cost-effective power supply structures can be built with less effort in design and maintenance. Furthermore, modular systems can be changed, resealed and expanded even after implementation. The proposed design approach proved its strengths in a laboratory test installation. Results or test runs are given at the end if this paper
Thermal Degradation of Electroplated Nickel Thermal Microactuators
No full textIn this paper, the thermal degradation of laterally operating thermal actuators made from electroplated nickel has been studied. The actuators investigated delivered a maximum displacement of ca. 20 mum at an average temperature of ~ 450degC , which is much lower than that of typical silicon-based microactuators. However, the magnitude of the displacement strongly depended on the frequency and voltage amplitude of the pulse signal applied. Back bending was observed at maximum temperatures as low as 240degC. Both forward and backward displacements increase as the applied power was increased up to a value of 60 mW; further increases led to reductions in the magnitudes of both displacements. Scanning electron microscopy clearly showed that the nickel beams began to deform and change their shape at this critical power level. Compressive stress is responsible for nickel pileup, while tensile stresses, generated upon removing the current, are responsible for necking at the hottest section of the hot arm of the device. Energy dispersive X-ray diffraction analysis also revealed the severe oxidation of Ni structure induced by Joule heating. The combination of plastic deformation and oxidation was responsible for the observed thermal degradation. Results indicate that nickel thermal microactuators should be operated below 200degC to avoid thermal degradation