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Power system planning is essential for ensuring development of a safe and stable power system. Articles on power system planning have been published in recent decades. In this paper, bibliometric analysis is applied to power system planning to identify its basic characteristics, and to summarize the research hotspots and trends. A total of 4562 publications were obtained from the Web of Science during 1971–2020. The 4562 publications cover 8136 keywords, 1526 journals, 107 countries/territories, and 2519 institutions. IEEE Transactions on Power Systems is the key journal in power system planning; USA, China, and England are the countries that dominate publication production. Research hotspots and trends were analyzed using author-keyword co-occurrence analysis and keyword burst detection. Four clusters were identified and topics from Cluster I (central nodes as power system stability and transient stability) and Cluster IV (central nodes as power system simulation and economics) are important for power system planning research. However, their relative popularities have declined over the past two decades. This indicates that Cluster II (central nodes as renewable energy, wind power, and energy storage) and Cluster III (central nodes as distributed generation and smart grids) will be the focus of future research. [ABSTRACT FROM AUTHOR]

In Part I of this paper we have introduced the closed-form conditions for guaranteeing regional frequency stability in a power system. Here we propose a methodology to represent these conditions in the form of linear constraints and demonstrate their applicability by implementing them in a generation-scheduling model. This model simultaneously optimises energy production and ancillary services for maintaining frequency stability in the event of a generation outage, by solving a frequency-secured Stochastic Unit Commitment (SUC). We consider the Great Britain system, characterised by two regions that create a non-uniform distribution of inertia: England in the South, where most of the load is located, and Scotland in the North, containing significant wind resources. Through several case studies, it is shown that inertia and frequency response cannot be considered as system-wide magnitudes in power systems that exhibit inter-area oscillations in frequency, as their location in a particular region is key to guarantee stability. In addition, securing against a medium-sized loss in the low-inertia region proves to cause significant wind curtailment, which could be alleviated through reinforced transmission corridors. In this context, the proposed constraints allow to find the optimal volume of ancillary services to be procured in each region. [ABSTRACT FROM AUTHOR]

This article presents information regarding a workshop organized by the Information Processing in Medical Imaging (IPMI), in 2003. IPMI occupies an important position in the scientific calendar. Every two years it brings together leading researchers in medical image formation, analysis and interpretation, for an international workshop that allows extensive, in-depth discussion of new ideas. IPMI 2003 was held over five days in July 2003 at St Martin' s College, Ambleside-in the heart of the English Lake District. Full papers were invited on any aspect of information processing in medical imaging, with particular emphasis on exploring generic mathematical or computational principles.

This paper describes the application of an interactive theorem-proving assistant and specification support tool called mural in the specification and verification of a small VDM development. The paper's intention is to give a feel for how mural works and of mural's applicability as a tool in specifying and verifying software. [ABSTRACT FROM AUTHOR]

Very short-term load forecasting predicts the loads in electric power system one hour into the future in 5-min steps in a moving window manner. To quantify forecasting accuracy in real-time, the prediction interval estimates should also be produced online. Effective predictions with good prediction intervals are important for resource dispatch and area generation control, and help power market participants make prudent decisions. We previously presented a two level wavelet neural network method based on back propagation without estimating prediction intervals. This paper extends the previous work by using hybrid Kalman filters to produce forecasting with prediction interval estimates online. Based on data analysis, a neural network trained by an extended Kalman filter is used for the low-low frequency component to capture the near-linear relationship between the input load component and the output measurement, while neural networks trained by unscented Kalman filters are used for low-high and high frequency components to capture their nonlinear relationships. The overall variance estimate is then derived and evaluated for prediction interval estimation. Testing results demonstrate the effectiveness of hybrid Kalman filters for capturing different features of load components, and the accuracy of the overall variance estimate derived based on a data set from ISO New England. [ABSTRACT FROM PUBLISHER]

This paper presents an empirical model for the statistical prediction of site diversity gain on earth space propagation paths. A modelling approach is described which incorporates 46 months of Nimrod rain radar data recorded in South England. The dual site diversity (SD) gain is developed as a function of several parameters, including time percentage of average year, site separation, baseline orientation, link frequency and path elevation angle. The model performs with an overall root mean square error of 1.87 dB computed over a wide variety of link configurations with elevation angles ranging from 10^\circ to 50^\circ and transmission frequencies from 16 to 50 GHz. The performance of the new model is checked against satellite beacon measurements as well as the empirical and physical models recommended by ITU-R. [ABSTRACT FROM PUBLISHER]

Cybernetics is a broad subject, encompassing many aspects of electrical, electronic, and computer engineering, which suffers from a lack of understanding on the part of potential applicants and teachers when recruiting students. However, once the engineering values, fascinating science, and pathways to rewarding, diverse careers are communicated, appropriate students can be very interested in enrolling. At the University of Reading, Reading, U.K., a key route for outreach to prospective students has been achieved through the use of robots in interactive talks at schools, competitions (often funded by Public Understanding of Science projects), a collectable fortnightly magazine, exhibitions in museums, open days at the University, and appearances in the media. This paper identifies the interactive engagement, anthropomorphic acceptability, and inspirational nature of robots as being key to their successful use in outreach activities. The statistical results presented show that the continued popularity of degrees at Reading in cybernetics, electronic engineering, and robotics over the last 20 years is in part due to the outreach activities to schools and the general public. [ABSTRACT FROM AUTHOR]

This paper describes a novel adaptive battery model based on a remapped variant of the well-known Randles' lead-acid model. Remapping of the model is shown to allow improved modeling capabilities and accurate estimates of dynamic circuit parameters when used with subspace parameter-estimation techniques. The performance of the proposed methodology is demonstrated by application to batteries for an all-electric personal rapid transit vehicle from the Urban Light TRAnsport (ULTRA) program, which is designated for use at Heathrow Airport, U.K. The advantages of the proposed model over the Randles' circuit are demonstrated by comparisons with alternative observer/estimator techniques, such as the basic Utkin observer and the Kalman estimator. These techniques correctly identify and converge on voltages associated with the battery state-of-charge (SoC), despite erroneous initial conditions, thereby overcoming problems attributed to SoC drift (incurred by Coulomb-counting methods due to overcharging or ambient temperature fluctuations). Observation of these voltages, as well as online monitoring of the degradation of the estimated dynamic model parameters, allows battery aging (state-of-health) to also be assessed and, thereby, cell failure to be predicted. Due to the adaptive nature of the proposed algorithms, the techniques are suitable for applications over a wide range of operating environments, including large ambient temperature variations. Moreover, alternative battery topologies may also be accommodated by the automatic adjustment of the underlying state-space models used in both the parameter-estimation and observer/estimator stages. [ABSTRACT FROM AUTHOR]

The Alpha Magnetic Spectrometer (AMS) isa particle physics experiment based on the International Space Station (ISS). At the heart of the detector is a large superconducting magnet, cooled to a temperature of 1.8 K by superfluid helium. The magnet and cryogenic system have been designed and built by Scientific Magnetics (formerly Space Cryomagnetics) of Culham, England. This paper describes the results from magnet testing, and the final assembly of the magnet and flight cryostat. [ABSTRACT FROM AUTHOR]

This paper investigates the utility of different parameters from polarimetric interferometric synthetic aperture radar (InSAR) data for the identification of ground pixels in a woodland area to enable accurate digital terrain model (DTM) generation from the InSAR height of the selected ground hit pixels. The parameters assessed include radar backscatter, interferometric coherence, surface scattering proportion (based on Freeman-Durden decomposition), and standard deviation of the interferometric height. The method is applied to Monks Wood, a small seminatural deciduous woodland in Cambridgeshire, U.K., using airborne E-SAR data collected in June 2000. The 1428 variations of SAR-derived terrain models are validated with theodolite data and a light detection and ranging-derived DTM. The results show that increasing the amount of data used in the DTM creation does not necessarily increase the accuracy of the final DTM. The most accurate method, for the whole wood, was a fixed-window minimum-filtering algorithm, followed by a mean filter. However, for a spatial subset of the area using the v3 backscattering coefficient to identify ground pixels outperforms the minimum filtering method. The findings suggest that backscatter information may often be undervalued in estimating terrain height under forest canopies. [ABSTRACT FROM AUTHOR]

The article presents the message of the chairman of the COMPUMAG 2003 Committee. The author states that he is glad to present the selected papers presented at the COMPUMAG Saratoga Springs conference. Those papers are published in the March 2004 issue of the journal "IEEE Transactions of Magnetics." The author also states that the first COMPUMAG conference was held in 1976 in Oxford, England. Since then the society and its conferences have continued to grow in numbers, in significance, in international renown and respect. The author is honored to carry on the tradition of presenting the leading research and thought in the area of computational electromagnetics.

An advanced model-based control technique for regulating the blood glucose for patients with Type 1 diabetes is presented. The optimal insulin delivery rate is obtained off-line as an explicit function of the current blood glucose concentration of the patient by using novel parametric programming algorithms, developed at Imperial College London. The implementation of the optimal insulin delivery rate, therefore, requires simple function evaluation and minimal on-line computations. The proposed framework also addresses the uncertainty in the model due to interpatient and intrapatient variability by identifying the model parameters which ensure that a feasible control law can be obtained. The developments reported in this paper are expected to simplify the insulin delivery mechanism, thereby enhancing the quality of life of the patient. [ABSTRACT FROM AUTHOR]

The article offers information about the 36th European Microwave Conference that was held at the International Conference Center in Manchester, England on September 10-15, 2006. The event has become truly international event with papers submitted from 52 countries. During the event, all the meetings were well attended with the most popular sessions in the field of metamaterials.