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Software Solutions for Antenna Design Exploration: A Comparison of Packages, Tools, Techniques, and Algorithms for Various Design Challenges
Get PDFNumerous software packages exist for solving antenna design optimization problems, with many of these employing a variety of approaches, leading, in turn, to variations in optimization performance. Antenna designers, often not fully schooled in optimization, can be confused as to which algorithm in which software package should be used. A wrong choice can cause the failure of the optimization or the expending of considerable time on the computationally expensive 3D electromagnetic (EM) simulations involved. While it is true that the various algorithms, combined with the variety of complex challenges found in different real-world scenarios make a direct comparison among tools difficult, a robust attempt at such an evaluation is overdue
Application of Ultrasonic Guided Waves for Surface Roughness Measurement
Get PDFSurface roughness is inherently a product of manufacturing process and is often undesirable. In surface metrology, the term “roughness” is typically applied to the highfrequency and short-wavelength parameters of a finished surface. In practical applications, the surface roughness is directly associated with the quality of the manufacturing. This study proposes the use of ultrasonic surface guided waves to characterize the surface roughness amplitude and frequency during the manufacturing process. Finite element modeling (FEM) of acoustic wave propagation along a rough surface has revealed that there is a cut-off threshold for Rayleigh wave propagation, which is indicative of the surface roughness description. This cut-off occurs for a particular ratio of the spatial surface waviness and the acoustic wavelength, and the detection of the resulting wave attenuation and decay characterizes the surface roughness. If such a measurement system can be used in-line with the production process then it could signal adjustment of the material deposition rate when needed to achieve the required product quality
Comparative study on foaming and emulsifying properties of different beta-lactoglobulin aggregates
Get PDFDifferent conditions in food processing lead to different aggregates of protein. β-Lactoglobulin nanoparticles (BLGNPs) and fibrils (BLGFs) were prepared by adjusting pH and temperature, and thereby their foaming and emulsifying properties were compared to native globular β-lactoglobulin (NGBLG) at pH 7.0 and pH 4.0. A foam analyser, a microparticle size analyser, an interfacial rheometer and an atomic force microscope (AFM) were used to characterise foaming/emulsifying functionalities and interfacial microstructures/mechanical properties. The foam and emulsion stabilities were assessed by measuring the decay of foam height and the variation of emulsion droplet size, and both were found to be in the order of BLGFs > NGBLG > BLGNPs. Foams were more stable at pH 4.0 while emulsions were more stable at pH 7.0. Surface dilatational modulus (E) of NGBLG and its aggregates at pH 4.0 was greater than that at pH 7.0, with BLGFs showing the highest value of E and thus the highest resistance to membrane damage. The emulsion prepared with NGBLG and its aggregates had more negative charges at pH 7.0 than at pH 4.0. The foaming stability seemed to be more controlled by interfacial elasticity while the emulsion stability was more determined by surface charges. AFM analysis demonstrated different microstructures at the air–water interface between pH 4.0 and 7.0 and among the different protein aggregates, which could well explain their foaming and emulsifying properties
The potential of Contribution Analysis to alcohol and drug policy strategy evaluation: an applied example from Wales
Get PDFContribution analysis (CA) is being increasingly favoured as a policy evaluation tool. This includes application to evaluate alcohol and drug policies. This paper reflects on one such example and begins by providing a brief overview of CA as an evaluative research method. It then describes the way in which CA was applied to evaluate alcohol and drug policy in Wales, one of the constituent countries of the UK. This paper reports on two issues. First, how the theory of CA was translated into practice. Second, the key learning points for us as evaluators that arose out of the utilisation of this method. The article highlights that our use of CA enabled a rich exploration of programmes within their contextual setting, and had a range of limitations and considerable challenges associated with identifying and explaining causalities. Within these methodological discussions, we also illustrate how the policy was more successful in elements closer to its nomenclature framing; i.e. harm reduction, than it was to other incorporated aims. The analysis presented in this paper will be useful across a range of jurisdictions where the need to evaluate drug and alcohol policy and practice initiatives may arise
An ANN-based temperature controller for a plastic injection moulding system
Get PDFThis paper proposes an approach to an ANN-based temperature controller design for a plastic injection moulding system. This design approach is applied to the development of a controller based on a combination of a classical ANN and integrator. The controller provides a fast temperature response and zero steady-state error for three typical heaters (bar, nozzle, and cartridge) for a plastic moulding system. The simulation results in Matlab Simulink software and in comparison to an industrial PID regulator have shown the advantages of the controller, such as significantly less overshoot and faster transient (compared to PID with autotuning) for all examined heaters. In order to verify the proposed approach, the designed ANN controller was implemented and tested using an experimental setup based on an STM32 board
The role of universities in peripheral regions: the case of the North Wales and Mersey Dee area
Get PDFThe purpose of this paper is to address how universities contribute through a helix model of partnership to regional development in a peripheral but functionally connected area which finds itself outside major conurbations. In doing so, it shows how local universities may collaborate with each other and with other institutional actors, including the private sector, to gather data on how their graduates contribute to the regional economy. A case study of the North Wales Mersey Dee area (the ‘NWMD’), a cross-border region within the UK, provides the evidence base. There are gaps in international studies into how universities contribute to the development of their cities and regions, because these studies typically assume that the university is part of an urban concentration with the impact of their development and engagement radiating out into the hinterland. This study explores a scenario with a more dispersed picture, requiring even more effort from key stakeholders, along with the universities, to effect positive change through a policy agenda of ‘place-based’ strategies. Recommendations are made for longitudinal studies in similarly peripheral and under-performing regions to gauge how universities can work within local partnerships, leveraging government-backed investment to drive improvements
Protein/polysaccharide intramolecular electrostatic complex as superior food-grade foaming agent
Get PDFHigh-performance foaming agents are widely required in the food industry. In this study, the relationship between electrostatic interaction of whey protein isolate (WPI)/alginate (ALG) and the resultant foaming properties were investigated systematically. The phase diagram of WPI/ALG was established in terms of protein/polysaccharide mixing ratio (r) and pH. The results show that the foaming capacity of WPI/ALG complexes is almost the same across different regions of the phase
diagram, while the foam stability varies significantly. At pHs 7.0 and 0.5 where no electrostatic complexation occurs, the foam stability is found to decrease monotonically with decreasing r. At pH 4.0 and particular mixing ratios, i.e., r = 1 and 2, intramolecular soluble complexes are formed and the particular WPI/ALG complexes yield the best foam stability, as compared to other electrostatic complexes or individual components. The half-life (t1/2) of the foams stabilized by the intramolecular electrostatic complexes is as long as 4000 s at a very low WPI/ALG concentration of 0.1% w/w. The foaming properties are in line with the foam viscosity, interfacial adsorption behavior and
microstructures of the complexes observed at the air-water interface. This demonstrates that the protein/polysaccharide intramolecular electrostatic complex, more specifically at the stoichiometry, could potentially act as a superior foaming agent in the food industry
A Miniaturized Wide Band Implantable Antenna for Biomedical Application
Get PDFIn this paper, a miniaturized high gain antenna was designed for biomedical applications. The designed antenna operates on the industrial, medical, and scientific(2.40 - 2.4835) GHz band. The proposed antenna consists of the radiating element having rectangular, and circular slots, and a ground plane with rectangular slots. The total volume of the designed antenna is (7x7xO.2) mm 3 , and the thickness of the superstrate and substrate is 0.1 mm. The Rogers ULTRALAM (e , = 2.9, tanD = 0.0025) material is used for substrate and superstrate. The proposed antenna is placed inside the different phantoms of the human body. The maximum gain achieved by the simulations of the proposed antenna is -12 dBi at 2.45 GHz. The designed antenna has better results than the antennas discussed in the literature in term of size, gain, and bandwidth
Assessment of engineering mathematics in the context of distance learning
Get PDFMathematics is a crucial component of programmes on engineering, science and technology. In the context of computerised distance learning education, the subject of engineering mathematics is often delivered and assessed through a digital learning environment. This paper gives an overview of the history of distance learning education and its mathematics component. It also discusses the most popular on-line automated technologies applied to the assessment and evaluation of engineering mathematics including problems of the on-line representation of mathematical graphs and equations in the assessment material
The Basic Social Process of Perceptive Familiarizing: Making a Difference with Scenario Assessment in Executive Education
Get PDFStakeholder data gathered during the pre-validation stage of an Executive MBA programme revealed a skill deficit from the perspective of both sponsoring employers and students. The omission is practitioner application and behavioural techniques expected in a corporate setting. This extended abstract summarises a solution to this problem.
Relevant literature, of which a summary is provided, indicates support for the problem. A basic social process, a technique from classic grounded theory, is used to indicate a sense of progression in solving the problem and is conceptualised as perceptive familiarizing.
Recommendations to develop scenario assessment with increased frequency conclude the extended abstract