5,350 research outputs found
Kink Chains from Instantons on a Torus
We describe how the procedure of calculating approximate solitons from
instanton holonomies may be extended to the case of soliton crystals. It is
shown how sine-Gordon kink chains may be obtained from CP1 instantons on a
torus. These kink chains turn out to be remarkably accurate approximations to
the true solutions. Some remarks on the relevance of this work to Skyrme
crystals are also made.Comment: latex 17 pages, DAMTP 94-7
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Image Transformations and Printing of Plaster Layers in Spiral Growth Manufacturing
Spiral growth manufacturing (SGM) is a high speed rapid manufacturing technique in
which objects are built up, layer by layer, by simultaneously depositing, levelling and selectively
consolidating thin powder layers onto a rotating build platform. The size and position of the
jetted droplets are mapped by the position and greyscale level of pixels within an 8 bit greyscale
bitmap image. This paper reports on the development of software in which mathematical
algorithms apply geometric transformations to images in preparation for printing onto a rotating
substrate. In support of this work, dimensional accuracy measurements of printed images and
methods to correct radial print density variations are reported. The accuracy of printed images
were found to be within ±0.2mm of their predicted size. The experimental work is briefly
extended to the direct printing of plaster layers, formed by mixing two reactive ink solutions.Mechanical Engineerin
An Insurance-based Approach to Improving SME Cyber Security
There has been increasing concern in recent years about the lack of urgency in SMEs regarding security of their information. Concern stems not only from the risks the SMEs are taking not only with their own data, but also with the data they share with supply chain partners. Current surveys have shown that the situation is getting worse with human error compounded by cybercriminals exploiting weaknesses in SME systems and using them to hack supply chain hubs.
In this paper, a researcher and a practitioner from the UK investigate possible reasons for SME apparent lack of interest in securing data, or developing information security management systems (ISMSs). In the absence of UK legislation, the only way SMEs are likely en masse to improve their information security is through pressure from supply chain partners and particularly supply chain hubs. The authors present an interesting development in cyber liability insurance which provides the basis for a cost-effective solution that will encourage good information assurance across the supply chain.
The solution offered in association with a major International insurer is explained in detail in this paper. It has the dual advantages for participating SMEs of ensuring that they achieve a level of information assurance that will offer them actual protection, and at the same time provide them with insurance that will protect them financially against data breaches or other costly consequences of weak information security. The scheme used will provide actuarial evidence for the insurer to further refine the model. Clients that cannot show evidence of a base level of security will not get insurance cover; by contrast those assessed as being more secure will be eligible for a discount. The tool used in this model is a self-assessed version of the IASME or Cyber Essentials information assurance standards, both recently developed in the UK to meet the needs of SMEs wishing to safeguard their precious information but not possessing the resources to achieve the ISO27001 standard
BRAND EXTENSIONS IN CONFECTIONARY; THE MARS DELIGHT
The concept of brand extension has been considered for several decades, drawing of work by Tauber (1981). Effective branding requires an understanding of areas such as segmentation, targeting and positioning which are critical in developing a successful brand management strategy. This research has focused on the unique nature of the highly competitive confectionery market, looking at recent brand activity by Masterfoods with emphasis on the launch of the Mars Delight, a brand extension recently launched in the UK and Ireland. The methodology utilised both qualitative and quantitative techniques to satisfy the research objectives. Initially the core purpose of this study was to investigate the alternative brand strategies available to drive growth in the competitive UK confectionery market. However, in conducting the initial research it became apparent that a particular model used as a basis to support brand strategy development was not adequate for this highly competitive, dynamic market sector. Therefore this study strove for a better understanding of brand management with the aim of providing an updated framework to guide brand strategy. The proposed Jigsaw Brand Matrix aims to extend the existing literature on brand portfolio strategy, and is hoped that it will be a valuable contribution to marketing theory
Reducing the energy consumption of heavy goods vehicles through the application of lightweight trailers: Fleet case studies
Reducing the empty weight of articulated heavy goods vehicle trailers is one avenue that needs to be explored in reducing the carbon footprint of the road freight industry as a whole. A statistical analysis of two heavy goods vehicle fleets operating in the United Kingdom has helped to identify double-deck trailers used in grocery haulage and 'walking-floor' trailers used in bulk haulage as two examples of trailers that can benefit significantly from lightweighting. Energy consumption of numerous articulated heavy goods vehicles is quantified through an idealised drive cycle analysis reflecting a long haul journey over a highway. This energy analysis allows for a mass energy performance index to be established. The analysis has shown that reducing the empty weight of trailers by 30% can cause reductions of up to 18% and 11% in mass energy performance index for double-deck trailers and 'walking-floor' trailers respectively. Using this approach, trailers that will benefit the most from weight reduction can be identified systematically, allowing for lightweighting strategies to be implemented more effectively. Strategies to reduce empty trailer weight and improve vehicle utilisation are also discussedThe authors would like to acknowledge the financial support from the members of the Centre for Sustainable Road Freight and from the Engineering and Physical Sciences Research Council (Grant Reference EP/K00915X/1).This is the final version of the article. It first appeared from Elsevier via http://dx.doi.org/10.1016/j.trd.2015.09.01
Analysis of industrial reactive powders flow properties at high temperature
Changes of bulk flow properties of two different types of titanium dioxide powders were measured at room temperature and 500 °C using the High Temperature Annular Shear Cell. A significant increase of the macroscopic bulk flow properties was observed with increasing temperature, in particular with regard to the unconfined yield strength. A theoretical modelling procedure was proposed with the aim to relate the measured properties to the microscopic interactions between particles. The results indicated that the model might provide a good match with the experimental data if proper values for the model's parameters are taken into account
Flavor Symmetry and Topology Change in Nuclear Symmetry Energy for Compact Stars
The nuclear symmetry energy figures crucially in the structure of asymmetric
nuclei and, more importantly, in the equation of state (EoS) of compact stars.
At present it is almost totally unknown, both experimentally and theoretically,
in the density regime appropriate for the interior of neutron stars. Basing on
a strong-coupled structure of dense baryonic matter encoded in the skyrmion
crystal approach with a topology change and resorting to the notion of
generalized HLS (hidden local symmetry) in hadronic interactions, we address a
variety of hitherto unexplored issues of nuclear interactions associated with
the symmetry energy, i.e., kaon condensation and hyperons, possible topology
change in dense matter, nuclear tensor forces, conformal symmetry and chiral
symmetry etc in the EoS of dense compact-star matter. One of the surprising
results coming from the hidden local symmetry structure that is distinct from
what is given by standard phenomenological approaches is that at high density,
baryonic matter is driven by RG flow to the "dilaton-limit fixed point (DLFP)"
constrained by "mended symmetries." We further propose how to formulate kaon
condensation and hyperons in compact-star matter in a framework anchored on a
single effective Lagrangian by treating hyperons as the Callan-Klebanov
kaon-skyrmion bound states simulated on crystal lattice. This formulation
suggests that hyperons can figure in the stellar matter -- if at all -- when or
after kaons condense, in contrast to the standard phenomenological approaches
where the hyperons appear as the first strangeness degree of freedom in matter
thereby suppressing or delaying kaon condensation. In our simplified
description of the stellar structure in terms of symmetry energies which is
compatible with that of the 1.97 solar mass star, kaon condensation plays a
role of "doorway state" to strange-quark matter.Comment: 48 pages, 6 figures, version for publicatio
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Robotic path planning using NDT ultrasonic data for autonomous inspection
Copyright © M. Zhang et al. 2023. Robot deployed ultrasonic inspection for Non-Destructive Testing (NDT) offers several advantages including time efficiency gains, the reducing of repetitive manual workloads for operators and the enabling of inspection of environments hazardous to human health. Due to accuracy requirements, NDT robotic inspection has traditionally used the concept of digital twins for path planning activities. Recent development has sought to automate this process through visual feedback using low-cost camera sensors. However, these methods do not take into account the use of NDT data itself as part of the robot path planning process. As a consequence, poor path planning accuracy can result due to the inability of conventional cameras to capture internal defects or geometric features. This paper introduces a novel concept of using the NDT ultrasonic data as part of a robotic path planning feedback loop. Firstly, the robot is manually positioned near the start of a weld, and the ultrasonic data is collected. Next, algorithms are implemented to monitor changes in the weld geometry, to determine the robot's movement and pose based on real-time monitoring data, and to enable the robot to autonomously scan a weld with a minimum of operators input, path planning or digital twin. This is advantageous to NDT as visual sensors are unable to monitor geometric features within the weld. The ability to use the NDT data ensures the inspection continues at the optimal configuration (e.g. correct stand off and limiting probe skew), and achieves optimal path planning for NDT robots. The experimental results have shown that the tracking algorithm can effectively and accurately track defects in the sample during the ultrasonic probe detection process with an error rate within ±1 mm.This project was part of an initiative known as AEMRI (Advanced Engineering Material Research Institute which is funded by the Welsh European Funding Office (WEFO) using European Regional Development Funds (ERDF)
Hopf solitons in the Nicole model
The Nicole model is a conformal field theory in a three-dimensional space. It has topological soliton solutions classified by the integer-valued Hopf charge, and all currently known solitons are axially symmetric. A volume-preserving flow is used to construct soliton solutions numerically for all Hopf charges from 1 to 8. It is found that the known axially symmetric solutions are unstable for Hopf charges greater than 2 and new lower energy solutions are obtained that include knots and links. A comparison with the Skyrme–Faddeev model suggests many universal features, though there are some differences in the link types obtained in the two theories
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