Testing of powders for sensitivity to air effect segregation

A loss of blend homogeneity through handling operations can have a major influence on the mechanical properties of sintered products. Plant optimisation to minimise the potential for segregation of blends can be undertaken through an audit of handling operations combined with an evaluation of the materials that are handled through the process. The correct identification of the mechanism of segregation is essential to support strategies to implement the most efficient and cost-effective counter measures. In support of this type of industrial activity, a piece of test apparatus has recently been developed to provide measurements of segregation potential for powders (metal and mineral) that are prone to loss of homogeneity (by composition or particle size) when subjected to counter-directional air displacements through equipment. The test equipment is described and examples given of its output in industrial application

Balancing throughput and latency for an aerial robot over a wireless secure communication link

With the requirement for remote control of unmanned aerial vehicles (UAV) becoming more frequent in scenarios where the environment is inaccessible or hazardous to human beings (e.g. disaster recovery); remote functionality of a UAV is generally implemented over wireless networked control systems (WNCS). The nature of the wireless broadcast allows attackers to exploit security vulnerabilities through passive and active attacks; consequently, cryptography is often selected as a countermeasure to the aforementioned attacks. This paper analyses simulation undertaken and proposes a model to balance the relationship between throughput and latency for a secure multi-hop communication link. Results obtained indicate that throughput is more influential up to two hops from the initial transmitting device; conversely, latency is the determining factor after two hops

Centrifugal tester versus a novel design to measure particle adhesion strength and investigation of effect of physical characteristics (size, shape, density) of food particles on food surfaces

A new experimental procedure has been established and a novel Impact Adhesion Tester has been designed and constructed. In the experiment, the amount of powder detached from one side of a crisp substrate by the impact forces (48, 77 and 102 g-force) generated by the tester was measured. In addition, a centrifuge tester was used along with specially designed tubes for substrate housing. Centrifugal speed applied varied from 300 up to 4000 rpm. Crisps (3 cm diameter and 3 mm thickness) and wood veneer pieces (1 x 2 cm and 2 mm thickness) were used as test substrates and salt particles (63–125, 125–180, and 180–250 lm) were used as coating material after applying oil on the surface. The comparison between results obtained from two methods was discussed. In addition, spherical and crushed glass particles (150–180, and 212–250 lm) were used to investigate the effect of shape on adhesion strength. Significant changes in adhesion strength have been observed for particles with different sizes and shapes

Brookfield powder flow tester - Results of round robin tests with CRM-116 limestone powder

A low cost powder flowability tester for industry has been developed at The Wolfson Centre for Bulk Solids Handling Technology, University of Greenwich in collaboration with Brookfield Engineering and four food manufacturers: Cadbury, Kerry Ingredients, GSK and United Biscuits. Anticipated uses of the tester are primarily for quality control and new product development, but it can also be used for storage vessel design. This paper presents the preliminary results from ‘round robin’ trials undertaken with the powder flow tester using the BCR limestone (CRM-116) standard test material. The mean flow properties have been compared to published data found in the literature for the other shear testers

Requirements for a Nutrition Education Demonstrator

[Context and Motivation] Development of innovative ICT-based applications is a complex process involving collaboration of all relevant disciplines. This complexity arises due to differences in terminology, knowledge and often also the ways of working between developers in the disciplines involved. [Question/problem] Advances in each discipline bring a rich design environment of theories, models, methods and techniques. Making a selection from these makes the development of distributed applications very challenging, often requiring a holistic approach to address the needs of the disciplines involved. This paper describes early stage requirements acquisition of a mobile nutrition education demonstrator which supports overweight persons in adopting healthier dietary behaviour. [Principal idea/results] We present a novel way to combine and use known requirements acquisition methods involving a two stage user needs analysis based on scenarios which apply a theory-based model of behavioural change and are onstructed in two phases. The first phase scenarios specify an indicative description reflecting the use of the transtheoretical model of behavioural change. In the second phase, a handshake protocol adds elements of optative system-oriented descriptions to the scenarios such that the intended system can support the indicative description. [Contribution] The holistic and phased approach separates design concerns to which each of the disciplines contributes with their own expertise and domain principles. It preserves the applied domain principles in the design and it bridges gaps in terminology, knowledge and ways of working

Geological notes and local details for 1:10,000 sheets SU60NE, SE, SU61SE, SU70NW, NE, SW, SE, SU71SW, SZ69NE and SZ79NW, NE: the south-east Hampshire district: Havant and surrounding areas: part of 1:50,000 sheets 316 (Fareham) and 331 (Portsmouth)

This report describes the geology of a group of eleven National Grid 1:10 000 sheet areas as follows: SU60NE, SE; SU61SE; SU70NW, NE, SW, SE; SU71SW; SZ69NE and SZ79 NW, NE. These cover the coastal area of Portsea, Hayling and Thorney Islands, the eastern part of the Forest of Bere and the eastern part of Portsdown. The area reported on includes parts of 1:50 000 Geological Sheets 316) (Fareham) and 331 (Portsmouth)

Ferrite-filled cavities for compact planar resonators

Copyright © 2014 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Applied Physics Letters, Volume 104 (2), article 022405, and may be found at http://dx.doi.org/10.1063/1.4811521Sub-wavelength metallic planar cavities, closed at one end, have been constructed by wrapping aluminium foil around teflon or ferrite slabs. Finite cavity width perturbs the fundamental cavity mode frequency of ferrite-filled cavities due to different permeability inside and outside of the cavity, in contrast to teflon-filled cavities, while the cavity length required to achieve a specific resonance frequency is significantly reduced for a ferrite-filled cavity. Ferrite-filled cavities may be excited by an in-plane alternating magnetic field and may be advantageous for high-frequency (HF) and ultra HF tagging and radio frequency identification of metallic objects within security, manufacturing, and shipping environments.Engineering and Physical Sciences Research Council (EPSRC)University of Exeter Open Innovation FundCrown Packaging UK PL

Laser gas-discharge absorption measurements of the ratio of two transition rates in argon

The ratio of two line strengths at 922.7 nm and 978.7 nm of argon is measured in an argon pulsed discharge with the use of a single-mode Ti:Sapphire laser. The result 3.29(0.13) is in agreement with our theoretical prediction 3.23 and with a less accurate ratio 2.89(0.43) from the NIST database.Comment: 5 pages, 2 figures, 1 tabl