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Higher education (HE) in the UK has recently suffered financial pressure due to reduced central funding, and the requirement to widen student access. The estate is typically the second highest revenue expense and is an obvious target for efficiency gains. Sector‐wide statistics show there are opportunities for improving efficiency and many influential bodies have advocated space charging as a way of achieving them. This paper aims to investigate space performance indicators for evidence that space charging improves space use efficiency.

The approach used is a statistical analysis of space performance indicators for space charging and other higher education institution (HEIs).

Approximately one‐quarter of HEIs in the UK operated space charging in 2000‐2001 but only ten out of 31 space‐related performance indicators for the period 1998‐2001 suggest that increased efficiency results. Scrutiny of the background data shows they predominantly reflect differences in institutional wealth and activities, rather than space use management. Efficiency measures relating space to use provide no evidence of efficiency gains, suggesting that the application of charging as a space management tool is ineffective.

The methodology does not reveal the reasons for the disparity between theory and results of space charging. Qualitative research into the application of charging systems is required to provide an explanation.

The conclusions are important for HE managers who are considering implementing expensive systems to improve space efficiency. The results also shed light on the usefulness of space performance indicators for HE estates.

Although there have been many assertions that space charging will improve space use efficiency in the HE sector, this research provides evidence to the contrary.

The electric stress profiles of a needle‐plane electrode system used in the laboratory for investigation of tree initiation and growth have been studied. Results from analytical solution based on a hyperboloid shaped needle tend to differ from those from experiments. One reason is that in practice it is difficult to produce a needle of such a shape. Moreover, researchers have used various shaped needles for their tests. Presents the effects of these needle parameters on the electric stress profile. To simulate the presence of space charge, examines two models, i.e. spherical and cylindrical regions around the tip. For simplicity, the space charge was assumed to be uniformly distributed in the confined region. Results show that space charges can enhance or reduce the electric stress adjacent to the needle tip depending on the nature of the applied voltage.

The purpose of this paper is to develop a numerical simulation method based on the transient upstream finite element method (FEM) and Schottky emission theory to reveal the distribution characteristics of space charge in oil-paper insulation.

The main insulation medium of the converter transformer in high voltage direct current transmission is oil-paper insulation. However, the influence of space charge is difficult to be fully considered in the insulation design and simulation of converter transformers. To reveal the influence characteristics of the space charge, this paper proposes a numerical simulation method based on Schottky emission theory and the transient upstream FEM. This method considers the influence of factors, such as carrier mobility, carrier recombination coefficient, trap capture coefficient and diffusion coefficient on the basis of multi-physics field coupling calculation of the electric field and fluid field.

A numerical simulation method considering multiple charge states is proposed for the space charge problem in oil-paper insulation. Meanwhile, a space charge measurement platform based on the electrostatic capacitance probe method for oil-paper insulation structure is built, and the effectiveness and accuracy of the numerical simulation method is verified.

A variety of models are calculated and analyzed by the numerical simulation method in this paper, and the distribution characteristics of the space charge and total electric field in oil-paper insulation medium with single-layer, polarity reversal of plate voltage and double-layer are obtained. The research results of this paper have the guiding significance for the engineering application of oil-paper insulation and the optimal design of converter transformer insulation.

A method is developed for calculating the power loss due to corona on three‐phase transmission lines in fair weather. In this method, emission of ions takes place from the coronating phase conductors into the surrounding space when the conductor surface field exceeds the corona onset value. The space charges are simulated by discrete line charges, and the charge simulation technique is used to calculate the charge emission from the phase conductors during corona periods over both the positive and negative half‐cycles. The displacement of the space charges is governed by the prevailing field, which sums the contributions of all discrete line charges in space and those simulating the phase conductor. The calculated corona power loss values agreed well with those measured experimentally.

In high voltage direct current (HVDC), power cables heat is generated inside the conductor and the insulation during operation. A higher amount of the generated heat in comparison to the dissipated one, results in a possible thermal breakdown. The accumulation of space charges inside the insulation results in an electric field that contributes to the geometric electric field, which comes from the applied voltage. The total electric field decreases in the vicinity of the conductor, while it increases near the sheath, causing a possible change of the breakdown voltage.

Here, the thermal breakdown is studied, also incorporating the presence of space charges. For a developed electro-thermal HVDC cable model, at different temperatures, the breakdown voltage is computed through numerical simulations.

The simulation results show a dependence of the breakdown voltage on the temperature at the location of the sheath. The results also show only limited influence of the space charges on the breakdown voltage.

The study is restricted to one-dimensional problems, using radial symmetry of the cable, and does not include any aging or long-term effect of space charges. Such aging effect can locally increase the electric field, resulting in a reduced breakdown voltage.

A comparison of the breakdown voltage with and without space charges is novel. The chosen approach allows for the first time to assess the influence of space charges and field inversion on the thermal breakdown.

The purpose of this paper is to optimize and improve a bipolar charge transport (BCT) model used to simulate charge dynamics in insulating polymer materials, specifically low-density polyethylene (LDPE).

An optimization algorithm is applied to optimize the BCT model by comparing the model outputs with experimental data obtained using two kinds of measurements: space charge distribution using the pulsed electroacoustic (PEA) method and current measurements in nonstationary conditions.

The study provides an optimal set of parameters that offers a good correlation between model outputs and several experiments conducted under varying applied fields. The study evaluates the quantity of charges remaining inside the dielectric even after 24 h of short circuit. Moreover, the effects of increasing the electric field on charge trapping and detrapping rates are addressed.

This study only examined experiments with different applied electric fields, and thus the obtained parameters may not suit the experimental outputs if the experimental temperature varies. Further improvement may be achieved by introducing additional experiments or another source of measurements.

This work provides a unique set of optimal parameters that best match both current and charge density measurements for a BCT model in LDPE and demonstrates the use of trust region reflective algorithm for parameter optimization. The study also attempts to evaluate the equations used to describe charge trapping and detrapping phenomena, providing a deeper understanding of the physics behind the model.

This paper aims to clarify the semi-conductive behavior of the passive layer formed in concrete environment without and with presence of chloride ions under different loading conditions. Passivation and depassivation of steel play an essential role in the subsequent stages of the corrosion process. Due to the nature of passive films on metals, they show electrochemical properties of a semi-conductor.

A C-ring model was proposed in this experiment to induce stress on the specimens. Specimens under different levels of compressive and tensile loadings were exposed to chloride-free and chloride-contaminated solutions and their semi-conductive behavior was investigated using Mott–Schottky technique.

Irrespective of the type and magnitude of the applied load, the passive film on rebars in simulated concrete pore solution is a highly disordered n-type semi-conductor. In all specimens, the presence of chloride ions decreases the slope of the Mott-Schottky plots, the donor density and the space charge layer thickness, which leads to a thinner passive film. Results indicate that steel specimens immersed in chloride-free pore solution under tensile loadings passivate more rapidly compared to those under compressive loadings. However, the situation in chloride-contaminated solution is different, and steel under tensile stress exhibits more corrosion than steel under compressive stress or under no load.

Reinforced concrete structures inevitably experience variable mechanical loads, and continuous degradation from aggressive environments. Therefore, it is imperative to study the synergic impact of different types of mechanical loadings and exposure to chloride ions on this process. This paper fulfils this need.

This chapter explains how and why local parking policies are developed, the sometimes conflicting relationship between parking, revenue raising and economic development and the circumstances in which it may be appropriate to use parking policy as a demand management tool.

This chapter offers a review of prior research and literature on the topic parking management and further explores the impacts and difficulties of parking management. Moreover, empirical data in this chapter comes from the authors’ own survey study of southern, eastern and southeastern European cities about their parking problems and policies.

The findings of this chapter show that there is a need to consider what parking solutions cities may choose and what solutions might work for them. It is difficult to say that very different solutions will suit cities of different sizes, but rather that the level of implementation of the solutions must be related to the scale of the problem in each city, and its citizens’ demands. In addition, each city must work within its particular legislative context, which is why certain solutions might not work in some cities.

Parking policy and parking management are key to urban mobility and to managing its negative effects. It is possible to develop a car parking policy that will manage the negative impacts of urban car use whilst also supporting business and the economy; but this is a balancing act, which is why it is important to learn from the experience of other places, as we have shown in this chapter. Parking demand and the response of different cities to it are very important when considering the rise of car use in Europe and other parts of the world. Future solutions for parking problems are detailed at the end of this chapter.

This chapter offers a comprehensive overview of prior research in parking management and connects this overview to findings of the authors own survey in south, eastern and southeastern European cities. Very few studies have made similar connections and provided in-depth insights into parking management in European cities. Moreover, the research provides useful information for planners and professionals dealing with parking issues and what solutions might work in their city.