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Off-Site Modular Construction (OSMC) research has been a growing research area over the past two decades because of low productivity in construction. Tools are superior in factories and productivity is much higher compared to a stick built site. This has spawned the development small, factory built, rapidly deployable and flexible process plants to take advantage of the gains in OSMC productivity. Chemical process plant research is studying fast, automated design and configuration. In this paper, a literature review was performed on modular factory manufactured process plants. The literature review found that moving to small scale OSMC plant systems could enable cost and schedule savings and months of design time compared to the previous on-site assembly design. It was also found that while automation has been applied in earlier stages of the plant design process, a layout optimisation methodology has not been applied to small OSMC process plants. The paper then proposes to utilise a mathematical layout optimisation model to help design and construct modular process plants and considers how this may fit into the process plant design process, as well as considering the transport requirements for modules.

The Small Modular Reactor (SMR) concept is designed such that it will solve some of the construction problems of large reactors. SMRs are designed to be “shop fabricated and then transported as modules to the sites for installation” (IAEA, 2018). As a consequence they theoretically have shorter build schedules and require less capital investment (Locatelli et al., 2014). Factory built modules can also increase safety and productivity, due to higher quality tools and inspection available. A literature review has highlighted substantial work has been undertaken in the research, development and construction of different types of reactors and reactor modules but the design of balance of plant modules has not been extensively researched (Wrigley et al., 2018). The focus of this paper is a case study for balance of plant modules in a light water reactor which also could have applications to other reactor types. Modules that are designed for factory build and transport may be built in a standardized module approach. By maximizing module size for transport, this maximizes work offsite, to achieve the cost and schedule savings associated. A design method needs to be developed to help support this approach. To enable this, a three step method is proposed: group components into modules, layout the modules and arrange components inside the modules. The Shearon Harris nuclear power plant was chosen for its publically available data. A previous study on this plant used matrix reordering techniques to group components and heuristically assign them to large modules, built for construction in an assembly area on site, highlighting a potential capital cost savings of 15%. This paper utilizes the same allocation of components to modules as the previous study but aims to undertake the challenge of how balance of plant modules should be arranged. The literature review highlighted that although the facility and plant layout problem has been extensively researched, mathematical layout optimization has not been applied to nuclear power plants. Many techniques for layout optimization have been developed for facilities and process plants however. The work in this paper develops an optimization model using a genetic algorithm for module layout and allocation within a nuclear power plant. This paper analysed two configurations of modules, where balance of plant modules are located on either one or two sides of the nuclear island. The objective function was to minimise pipe length. In the original research, where the plant was configured for assembly on site, the balance of plant modules are located around three sides of the nuclear island. The objective function was calculated at 14,914. As the distances are calculated rectilinearly, this number would be higher in reality as pipework has to be routed around containment. The optimization reduced the objective function by 33.9% and 37.8% for the three and four floor layouts respectively when balance of plant modules are located on two sides of the nuclear island. Furthermore, when modules are located on one side of the nuclear island, the objective function was reduced by 45.4% and 46.1% for three and four floor layouts respectively. This will reduce materials used, reduce build time and hence reduce the cost of a nuclear power plant. This method will also save design time when developing the layout of modules around the plant.

Off-Site Modular Construction (OSMC) research has been a burgeoning research area over the past two decades due to low productivity of traditional construction methods. Some large Gen 3 reactors may employ an on-site assembly area similar to shipbuilding techniques. This OSMC productivity has attracted the interest of the nuclear industry with over 50+ designs in commercial development. Off-site modular construction has been estimated to reduce the capital cost of an SMR by up to 37.98% compared to a stick-built method. The IAEA highlights the first commercial SMR “shop built and road transported to site” has an earliest operation date of 2026 (IAEA, 2018). This research paper aims to understand the current state of modular design in nuclear power by reviewing current literature with a systematic literature review. What can new small modular reactor designs learn from modularisation in large nuclear. What design and analysis techniques have been developed that may aid the design considering design, schedule, transportation and supply chain? What is the state of the art in the module design process? The research provides knowledge gaps and recommendations for further research.

Interspecialty referrals are an essential part of most inpatient stays. With over 130 referrals occurring per week at the Royal Devon and Exeter Hospital, the process must be efficient and safe. The current paper-based ’white card' system was felt to be inefficient, and a Trust incident highlighted patient safety concerns. Questionnaires reinforced the need for improvement, with concerns such as a lack of referral traceability and delays in the referral delivery due to workload. The aims of the project were to improve patient safety and junior doctor efficiency in the referral process. Through appreciative enquiry and the PDSA (Plan-Do-Study-Act) model, an electronic referral system was developed, piloted within two specialties and later expanded to others with improvements made along the way based on user feedback. The system includes novel features including specialties ’acknowledging' a referral to allow referral progress to be tracked. The system stores all referrals, creating a fully auditable inpatient referral pathway. Qualitative data indicated improvement to patient safety and user experience (n=31). Timings for referrals were measured over a 6-month period; referrals became faster with the electronic system, with average time from decision to refer to referral submission improving from 2.1 hours to 1.9 hours, with a noted statistically significant improvement in timings on a statistical process control chart. An unexpected benefit was that patients were also reviewed faster by specialties. Measuring these changes presented a significant challenge due to the complexity of the referral process, and this was a big limitation. Overall, the re-design of a paper-based referral system into an electronic system has been proven to be more efficient and felt to be safer for patients. This is a sustainable change which is being rolled out Trust-wide. We hope that the reporting of this project will help others considering reviewing their inpatient referral pathways.

The UK Small Modular Reactor (UKSMR) programme has been established to develop an SMR for the UK energy market. Developing an SMR is a multi-disciplinary technical challenge, involving nuclear physics, electrical, mechanical, design, management, safety, testing to name but a few. In 2016 Upadhyay & Jain performed a literature review on modularity in Nuclear Power. They concluded that although modularisation has been utilised in nuclear to reduce costs, more work needs to be done to “create effective modules”. Hohmann et al also concluded the same for defining modules in the chemical process plant industry. The aim of this paper is to further define modules with a particular focus on an SMR for the UK market, the UKSMR. The methods highlighted may be relevant and applied to other international SMR designs or other types of plant. An overview and examination of modularisation work in nuclear to date is provided. The different configurations are defined for the Nuclear Steam Supply System (NSSS) in primary circuits and then for Balance of Plant (BOP) modules. A top level design process has been defined to aid in the understanding of design choices for current reactors and to further assist designing balance of plant modules. The paper then highlights areas for additional research that may further support module design and definition.

This paper presents a new type of series ac-processing pickup used in inductive-power-transfer applications. The proposed pickup uses an ac switch operating under zero-current-switching conditions in series with a resonant network to produce a controllable ac voltage source suitable for driving incandescent lights. When a rectifier is cascaded onto this pickup, it can also produce a precisely controlled dc voltage. This topology eliminates the need to use an extra buck converter after the traditional series pickup for controlling the output load voltage to a desired value, which may be different from the induced voltage of the pickup. Furthermore, this pickup has the ability to control the inductor current directly, and hence, eliminate the transient inrush current at startup for the series-tuned resonant tank. The circuit is analytically analyzed and the maximum efficiency for a 1.2-kW prototype is measured to be 93%.

Treatment delivery with active beam scanning in proton radiation therapy introduces the problem of interplay effects when pencil beam motion occurs on a similar time scale as intra-fractional tumor motion. In situations where fractionation may not provide enough repetition to blur the effects of interplay, repeated delivery or 'repainting' of each field several times within a fraction has been suggested. The purpose of this work was to investigate the effectiveness of different repainting strategies in proton beam scanning. To assess the dosimetric impact of interplay effects, we performed a series of simulations considering the following parameters: tumor motion amplitude, breathing period, asymmetry in the motion trajectory for the target and time required to change the beam energy for the delivery system. Several repainting strategies were compared in terms of potential vulnerability to a dose delivery error. Breathing motion perpendicular to the beam direction (representing superior-inferior type tumor motion in patients) was considered and modeled as an asymmetric sine function with a peak-to-peak amplitude of between 10 and 30 mm. The results show that motion effects cause a narrowing of the high-dose profile and widening of the penumbra. The 90% isodose area was reduced significantly when considering a large motion amplitude of 3 cm. The broadening of the penumbra appears to depend only on the amplitude of tumor motion (assuming harmonic motion). The delivered dose exhibits a shift of 10-15% of the tumor amplitude (or 1-5 mm) in the caudal direction due to breathing asymmetry observed for both sin(4)(x) and sin(6)(x) motion. Of the five repainting techniques studied, so-called 'breath sampling' turned out to be most effective in reducing dose errors with a minimal increase in treatment time. In this method, each energy level is repainted at several evenly spaced times within one breathing period. To keep dose delivery errors below 5% while minimizing treatment time, it is recommended that breath sampling repainting be employed using 5-10 paintings per field for an assumed tumor volume of 8.5 x 8.5 x 10 cm(3). For smaller tumor volumes more repaintings will be required, while for larger volumes five repaintings should be sufficient to achieve the required dose accuracy.

We report on the first measurement of 39Ar in argon from underground natural gas reservoirs. The gas stored in the US National Helium Reserve was found to contain a low level of 39Ar. The ratio of 39Ar to stable argon was found to be, 6 pages, 2 figures, 2 tables

A new rectifier with combined power flow control capability has been developed to simplify a series-tuned power receiver in inductive power transfer (IPT) applications. Since the traditional IPT receiver usually employs two separate stages (rectifier and power flow regulator) after the tuning circuit to obtain a required DC output voltage, the receiver circuit is often complicated and large. A big DC inductor often needs to be used in the power flow regulator, which further increases the size of the receiver circuit, especially for heavy current applications, because the DC inductor is often the largest component in such a circuit. The proposed rectifier using two MOSFETs and one blocking diode in a series-tuned IPT receiver eliminates the DC inductor, and a new control strategy with combined rectification and power flow control is developed to further reduce the complexity and size of the power receiver. The theoretical analysis of the proposed rectifier has been verified by simulation and experimental study, and a prototype series tuned power receiver has been built to receive about 50 watts of power when it is coupled to a push-pull resonant transmitter. The overall power efficiency of the full system has reached about 80%.

Traditional stage lighting systems inherently suffer significant cost in materials/installation and can be affected by audible noise when operating at mains frequency. A new circuit for stage lighting is introduced to mitigate these issues; it comprises a series tuned IPT pickup with a new AC control topology. This topology builds on previous work by improving the waveform across the load & pickup and by lowering the switch ratings. The circuit is analyzed, simulated and a working system is measured and presented herein, including the relationship between the switch and the reactive elements for the design. A 1.2 kW 240V Philips Broadway lamp is successfully powered by this controller. The waveforms across the load are sinusoidal which lower the peak values for a given RMS voltage or current level, reducing noise and simplifying the design. The output voltage is regulated to 1% by implementing closed loop control on the system.

This paper introduces a modified IPT pickup AC topology for stage lighting applications. The topology improves on previous work enabling lower switch ratings and improved waveform quality across the pick-up and at the light. Circuit analysis, simulations and measurements are presented that establish the relationship between the switch and the reactive elements for design. The circuit is shown to provide sinusoidal output waveforms across the load with lower peak values for a given RMS voltage or current level reducing noise and THD significantly while also improving efficiency. The new controller is implemented and used to power a 1.2kW 240V Philips Broadway lamp. Either feedback or feed-forward voltage control can used to control the output within 1% of that desired.

This paper presents a 1.2 kW Inductive Power Transfer (IPT) lighting system using the parallel AC processing pickup. The AC processing pickup has been shown as an efficient and economic approach for producing high frequency AC outputs. IPT technology provides electrical power in a contactless manner, allowing multiple 1.2kW stage lights to be configured anywhere along the IPT track. This significantly reduces the setup time and improves the flexibility of such a system. The first description of a feedback control system with the AC processing pickup is proposed to improve the performance. Experimental results are given for the 1.2kW lighting system.

The Data Quality Objective Procedure (DQOP) method aids implementing environmental polices, as engineering solutions. Pollution control issues identified and addressed through new environmental legislation need to be implemented. The metal matrix encapsulation (MME) treatment works as a toxicity reduction exercise that can legally control disposal of fly ashes from waste-to-energy plants. The MME process aids with the implementation of European Union (EU) legislation such as the Waste Incineration Directive by allowing fly ashes to be disposed of in landfill sites. By using the DQOP, as shown with the MME fly ash treatment, complex issues can be clearly identified and effectively controlled. The method considers various steps into which different activities can be addressed, agreed upon and allows engineering, financial and legal teams to cooperate. The EU is the world’s second largest economy with many waste management requirements. The DQOP can aid entry into this complex but rich economic opportunity.Copyright © 2005 by ASME

Mr Daniel Robertson Censaur Sea Consulting Services Ltd, 6th Floor, Ninnal House, 22 Sir William Newton St, Port Louis, Mauritius Dr Rod Barratt Department of Environmental and Mechanical Engineering Faculty of Technology, Open University Milton Keynes, United Kingdom The current situation for fly ash management and policy regulation in the United Kingdom / European Union, has developed the need for new toxicity reduction exercises. New EU wide policies are changing the type of treatment methods that can be legally used for the residues from waste-to-energy plants. In particular the disposal of flue gas treatment residues, which are classified as a hazardous waste, will not be acceptable to landfill according to the Waste Acceptance Criteria without a pre-treatment by 2007. This has raised a number of interesting engineering questions that need to be addressed. The novel TRE of metal matrix encapsulation has been designed based upon the principles of separation, isolation and treatment to meet these new criteria. Metal matrix encapsulation is a treatment program that employs existing industrial infrastructure to improve its usability and legal compliance.

The ownership of mobile telephones is now almost universal amongst the teenage population of the United Kingdom. Such telephones are a potential source of electromagnetic interference to medical equipment. We describe a case of troublesome interference with an electrocardiogram recording in a teenage patient whose mobile telephone was left switched on during a visit to hospital. This is likely to be a common reason for poor quality electrocardiographic recordings.