Superconducting fault current limiter application in a power-dense marine electrical system

Power-dense, low-voltage marine electrical systems have the potential for extremely high fault currents. Superconducting fault current limiters (SFCLs) have been of interest for many years and offer an effective method for reducing fault currents. This is very attractive in a marine vessel in terms of the benefits arising from reductions in switchgear rating (and consequently size, weight and cost) and damage at the point of fault. However, there are a number of issues that must be considered prior to installation of any SFCL device(s), particularly in the context of marine applications. Accordingly, this study analyses several such issues, including: location and resistance sizing of SFCLs; the potential effects of an SFCL on system voltage, power and frequency; and practical application issues such as the potential impact of transients such as transformer inrush. Simulations based upon an actual vessel are used to illustrate discussions and support assertions. It is shown that SFCLs, even with relatively small impedances, are highly effective at reducing prospective fault currents; the impact that higher resistance values has on fault current reduction and maintaining the system voltage for other non-faulted elements of the system is also presented and it is shown that higher resistance values are desirable in many cases. It is demonstrated that the exact nature of the SFCL application will depend significantly on the vessel’s electrical topology, the fault current contribution of each of the generators, and the properties of the SFCL device, such as size, weight, critical current value and recovery time

MetricsVis: A Visual Analytics Tool for Evaluating Multidimensional Data

Visualization for multidimensional data is a popular topic and many methods have been created to visualize this type of data. We developed a visual analytics tool to visualize multidimensional data for two distinct fields: resource allocation in law enforcement departments and phenotype traits of sorghum crops. For law enforcement departments, we designed a visualization tool to measure and compare police officer’s experience in different types of crimes. Our tool supports the analysis of the amount of experience each officer has in each crime category. Meanwhile, the field crop modeling project requires the visualization of the measured value of multiple traits of each sorghum category. In general, our visualization tool is now able to represent these multidimensional data in multiple graphs and charts, with a rich interaction set of selecting, grouping, and filtering. MetricsVis has been expanded this summer with the addition of 6 new graphs, the ability to use the sorghum crops dataset, and more data manipulation features. By being able to explore the data through several graphs and charts at the same time, this allows the user to easily query the data or find peculiarities in the data that they would have otherwise missed. We describe several case studies to validate the importance of our tool in analyzing the data in both projects. In the future, we would like to expand our tool for other similar datasets

Application of Additive Manufacturing to the Digital Restoration of Archaeological Artifacts

AbstractThis paper reports a substantial body of work that has been done in this area, which has been used to determine how Additive Manufacturing (AM) and subsequent processes should be optimally applied, and introduces a series of process maps that have been generated to guide future practical work with a combination of questionnaires and expert interviews for validating the process maps. The outputs from the research should prove to be valuable to anyone working in this field. The main contribution to knowledge is the characterisation of archaeological artefacts and the resultant process maps derived from this characterization

Visualization Tools for Design Support in SFF 437

When considering the use of SFF, there are many questions a designer might ask. What model orientation should be used, will the model have adequate aesthetic and functional properties, is the STL file suitable for transfer to the SFF machine? These questions could be answered by a comprehensive design support system for SFF. This paper addresses a number of components for such a system that can be met through the use of visualization tools. These include: 1. Visualization of surface roughness 2. Visualization of characteristic features (e.g. surface macro-texture) 3. Visual simulation of fabrication Example applications of these tools are presented together with a status review of their implementation to date. It is envisaged that these tools will be incorporated into an already existing network-based preprocessor used for visualization, repair and slicing of STL files. The direction of future work is also discussed which will include the visual representation of functionally graded materials (connected with FEM results).Mechanical Engineerin

Total syntheses of 11-acetoxy-4-deoxyasbestinin D, 4-deoxyasbestinin C, asbestinin-10, -20, -21 and -23

Six members of the asbestinin family of marine diterpene natural products have been synthesized in an efficient and stereoselective manner from a single oxa‐bridged intermediate. Five of these natural products have not been synthesized previously and the structures of four of them have been confirmed as those proposed originally or following revisions to the original structures. The fifth natural product—asbestinin‐21—has been shown to be a diastereomer of the compound that had been proposed previously

Bed-load effects on hydrodynamics of rough-bed open-channel flows

Peer reviewedPublisher PD

Broadband and low loss high refractive index metamaterials in the microwave regime

Copyright © 2013 American Institute of PhysicsA broadband, low-loss, isotropic, high refractive index metamaterial comprising an array of close-packed cubic elements of cross-linked square metal plates is demonstrated in the microwave regime. The structuring of the cubic elements reduces the diamagnetic response exhibited by arrays of solid metal cubes, whilst maintaining the strongly enhanced permittivity arising from capacitative coupling between adjacent metal elements. The corresponding increase in refractive index can be tailored through appropriate structuring of the faces and/or spacing of the cubes

Development and evaluation of AGNI : a distributed netgraph data collection and analysis tool

Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998.Includes bibliographical references (leaves 46-47).AGNI is a tool developed to facilitate the analysis of communication networks between people in large organizations. Determining patterns of communication within organiza­tions is critical to the analysis of the effectiveness of their structure. Until recently, large organizations presented a special problem. The copious amounts of data that had to be analyzed made the process slow and tedious. AGNI makes the job easier by automating many of the tasks involved in this process. It provides a user friendly graphical environ­ment in which data can be collected and analyzed. It also provides an easy way to display the data in a graphical format so that it is easy to visualize.by Ian J.C. Duggan.M.Eng

Enriching the Summer Palace’s cultural experience

Cultural Heritage occurs when visitors tell stories of exceptional experiences at historic sites - after their visit occurs. For the Summer Palace’s directors to create exceptional experiences, exhibition designers must understand how to tell stories that have great meaning to the Summer Palace’s national and international visitors. Our research targets this question – we propose developing innovative and unique storytelling methods through interactive exhibitions throughout the Summer Palace to suspend the visitor’s sense of reality; increasing their sense of flow, suggestion, and engagement. We suggest the Summer Palace for this research project due to its status as a UNESCO World Heritage Site seeking to increase its international reputation. If directors and exhibition designers understand how advanced technology, including immersive exhibitions and augmented reality, can meet educational, enjoyment, and emotional needs of the Summer Palace’s diverse visitors during festivals and tourist visits, we may increase existing visitor’s engagement, and capture new tourist groups - who previously ignored the Palace. We hope our work shall ultimately contribute to making the Summer Palace China’s foremost Cultural Heritage Site and festival epicentre

Palliative care needs in patients hospitalized with heart failure (PCHF) study: rationale and design

Abstract Aims The primary aim of this study is to provide data to inform the design of a randomized controlled clinical trial (RCT) of a palliative care (PC) intervention in heart failure (HF). We will identify an appropriate study population with a high prevalence of PC needs defined using quantifiable measures. We will also identify which components a specific and targeted PC intervention in HF should include and attempt to define the most relevant trial outcomes. Methods An unselected, prospective, near-consecutive, cohort of patients admitted to hospital with acute decompensated HF will be enrolled over a 2-year period. All potential participants will be screened using B-type natriuretic peptide and echocardiography, and all those enrolled will be extensively characterized in terms of their HF status, comorbidity, and PC needs. Quantitative assessment of PC needs will include evaluation of general and disease-specific quality of life, mood, symptom burden, caregiver burden, and end of life care. Inpatient assessments will be performed and after discharge outpatient assessments will be carried out every 4 months for up to 2.5 years. Participants will be followed up for a minimum of 1 year for hospital admissions, and place and cause of death. Methods for identifying patients with HF with PC needs will be evaluated, and estimates of healthcare utilisation performed. Conclusion By assessing the prevalence of these needs, describing how these needs change over time, and evaluating how best PC needs can be identified, we will provide the foundation for designing an RCT of a PC intervention in HF