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INDUSTRIAL catering is big business today with an annual turnover estimated at over £600 million per annum, of which half is paid in subsidies by employers. Because catering facilities are usually only one small part of most undertaking's activities and because it is a field about which most managers know little or nothing, it is frequently not supervised and controlled in the same way as most other departments. As a result, considerably more than is necessary is often spent on indifferent facilities. Instead, staff catering services can and should be treated as any other cost centre. Decisions affecting them and methods of controlling them should be reached in the same methodical, systematic way as for the rest of the undertaking. Here are key questions from a British Institute of Management checklist to help you assess your refreshment and meal facilities:

“It is generally accepted that the food industry must be scientifically based to cope with the problems, particularly of public health, which arise as new processes of growing, manufacturing, packaging and preserving food depart even further from traditional ways.”

The purpose of this paper is to analyze the limitations of conventional reactive and resistive filters employed in the open ports of microwave‐heating applicators, in order to know the limits of these filters as a function of the permittivity of the inner materials.

CST Studio Suite™ commercial electromagnetic software has been employed to simulate the behaviour of singly and doubly corrugated reactive filters. Additionally, several configurations for resistive filters implemented with water are assessed. Optimization procedures based on genetic algorithms have been used by modifying some geometric parameters of the filters in order to obtain the best possible bandstop response.

Results show the serious limitations of these filters depending on the electric permittivity of the inner materials.

These limitations restrict the type of the materials that can be processed, so there is a need for new structures which solve these problems.

Although extensively used in many applications, there are few works that analyze the behaviour of these filters as a function of the geometric parameters or the sample permittivity, and therefore this influence needs to be studied.

The purpose of this paper is to analyse some of the spectrum management policy implications of an evolving set of wireless technologies. Specially, deployment of heterogeneous networks (HetNets) as part of the rollout of long-term evolution networks and their expected use as the heart of next-generation services raises the question as to whether such networks should lead to any spectrum management policy changes.

The paper describes the use and variety of HetNets when using licensed and unlicensed or commons spectrum.

The paper demonstrates that there is little need to change current spectrum licensing regimes to deal with these networks in a licensed spectrum. However, it also shows that the deployment of HetNets other than WiFi in an unlicensed spectrum creates an information asymmetry, which means that spectrum regulators will find assessment of spectrum demand more difficult. The paper also highlights the problem facing spectrum regulators when there is a potential for interference to unlicensed services which are widely deployed but have no right to protection from interference.

Spectrum regulators will need to understand the extent to which an unlicensed spectrum is being used by mobile network operators to deliver wireless broadband services. This understanding is needed to be able to address potential interference with other services using an unlicensed spectrum and to be able to forecast spectrum demand.

The development of technologies that are designed to be used by existing mobile network operators for the delivery of wireless broadband services using an unlicensed spectrum creates novel regulatory challenges. This paper reviews some of these.

In the paper, a single-objective optimization problem characterized by high-frequency field analysis is investigated: the optimal design of a two-port microwave (MW) oven, taking into account the possibility of two independently controlled sources, with the aim of improving the efficiency is considered as the case study. The paper aims to discuss these issues.

A high-frequency field analysis has been coupled to a robust evolutionary-computing algorithm in order to create an appropriate procedure for the optimal design of a MW oven based on a cascade optimization: in the first step the optimized geometry has been identified, while in the second step the optimized electrical supply values have been synthesized. In particular, the direct problem has been faced by means of a 3D-FEM approach in order to obtain realistic results; the inverse problem has been faced by means of a derivative-free robust algorithm based on evolutionary strategy in order to get a fast convergence of the solution.

A new design procedure for high efficiency MW ovens for household application by means of the proposed numerical approach.

These results allow industrial designers to improve this kind of devices.

The original contribution of the paper is the systematic approach to the optimal design of a MW oven with multiple feeding, based on the link between an algorithm of evolutionary strategy optimization algorithm and a finite-element solver.

With the drastically changed pattern of the retail food trade in recent years in which the retailer's role has become little more than that of a provider of shelves for commodities, processed, prepared, packed and weighed by manufacturers, the defence afforded by the provisions of Section 113, Food and Drugs Act, 1955 has really come into its own. Nowadays it is undoubtedly the most commonly pleaded statutory defence. Because this pattern of trade would seem to offer scope for the use of the warranty defence (Sect. 115) in food prosecutions it is a little strange that this defence is not used more often.

To develop a method based on urea/microwave treatment for improving the dyeability of the flax fibre.

The treatment was carried out under a variety of conditions in terms of the power of the microwave, the time of microwave treatment and the use of urea in the treatment solution. The physical chemical properties of the treated flax fibres were characterised using a variety of techniques including scanning electron microscopy (SEM), X‐ray diffractometry, spectrophotometric measurement and tensile measurement.

It was found that the treated flax fibres had significantly improved dyeability. The causes to the improvement of the dyeability of the flax fibre were found to be the increased absorption of dye on the fibre and the increased reaction probability between the dye and the fibre. The procedure for optimum modification appeared to be soaking the flax fabrics in 10 per cent urea solution; treating the fabrics with microwave at 350 W for 2.5 minutes; and treating the fabrics with microwave at 700 W for one minute.

The treatment method developed addressed a problem of great concern in textile coloration, i.e. poor dyeability of flax fibre. The method developed provided a practical and effective solution to such a problem.

The method of treatment of flax fibre, involving soaking in urea and baking in microwave, for the improvement of dyeability was novel. The method could be adapted for use in industrial scale flax dyeing with satisfactory levels of exhaustion and fixation.

The new Hitachi factory producing microwave ovens employs a welding cell with robot handling. Anna Kochan reports from the Welsh Valleys.

The purpose of this paper is to based upon the joining and characterization (mechanical and metallurgical) of ferritic stainless steel (SS)-430 using a microwave hybrid heating (MHH) phenomenon.

The preliminary experiments were conducted using nickel-based powder as interface material using a domestic microwave oven at a frequency of 2.45 GHz and 900 W power for 720 s. The processed joint was metallurgically characterized by means of X-ray diffraction, Energy-dispersive X-ray spectroscopy and Field emission scanning electron microscopy. Mechanical characterization was done by means of tensile and Vickers’ microhardness testing to check the hardness and strength of the joint.

The metallurgical study revealed that the microstructure and formation of numerous phases of Fe₂Si₃ accompanied by chromium and nickel carbides. The average hardness of 359 Hv at the center of the joint and 637 Hv around the boundaries of the joint was observed. The tensile strength of the joint was observed to 471 MPa with an elongation of 9.02%. The worn surface of the joint signifies the presence of plastic deformation and it was limited due to the presence of harder phases such as Ni₃Si and Ni₃C.

The concept of microwave joining of metals is a very challenging task as the temperature can not be controlled in the inert atmosphere of the microwave. It has been also observed that at certain elevated temperatures, the material starts absorbing the microwaves; which is unknown. So, a more intensive study is required to overcome these kinds of limitations.

MHH technique can be used to process different materials such as ceramics, composites and polymers. SS-430 joined by microwave heating is highly corrosion resistive and has wide applications in refrigerators cabinet panels, dishwasher linings, chimney liners, lashing wires, etc.

As of the author’s best knowledge, no work has been reported on the joining of SS-430 which has huge potential in the industries. Also, no work has been reported on the characterization of microwave joined SS-430.

This paper aims to focus on the most popular technique nowadays, the use of microwave irradiation in organic synthesis; in a few years, most chemists will use microwave energy to heat chemical reactions on a laboratory scale. Also, many scientists use microwave technology in the industry. They have turned to microwave synthesis as a frontline methodology for their projects. Microwave and microwave-assisted organic synthesis (MAOS) has emerged as a new “lead” in organic synthesis.

Using microwave radiation for synthesis and design of fluorescent dyes is of great interest, as it decreases the time required for synthesis and the synthesized dyes can be applied to industrial scale.

The technique offers many advantages, as it is simple, clean, fast, efficient and economical for the synthesis of a large number of organic compounds. These advantages encourage many chemists to switch from the traditional heating method to microwave-assisted chemistry.

This review highlights applications of microwave chemistry in organic synthesis for fluorescent dyes. Fluorescents are a fairly new and very heavily used class of organics. These materials have many applications, as a penetrant liquid for crack detection, synthetic resins, plastics, printing inks, non-destructive testing and sports ball dyeing.

The aim value of this review is to define the scope and limitation of microwave synthesis procedures for the synthesis of novel fluorescent dyes via a simple and economic way.