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A systematic resilience and flexibility analysis of future power systems to address the impacts of climate change and Renewable Energy penetration is becoming increasingly important, as it is expected to have a great effect on the demand and supply portfolios. Depending on the intrinsic characteristics of each power system, different aspects have to be considered in the analysis since this cannot be universal for all power systems. To highlight this, the paper presents two different case studies pertaining to the Great Britain and Cyprus networks respectively. Firstly, the resilience of the Great Britain transmission network to future demand and supply scenarios (2020, 2030 and 2050) is evaluated using a reduced version of the current Great Britain transmission network. Subsequently, the future flexibility requirements of the isolated network of Cyprus are appropriately benchmarked against future energy mix scenarios that involve conventional generation and renewable energy penetration.

The reclosing time of a transmission line has a distinct influence on system stability. A new method of calculating the optimal reclosing time based on the transient energy function (TEF) is presented in this paper. It has been shown that an optimal reclosing time can be used to set the autoreclosing device so that the system stability or power-transfer capability can be significantly improved. Though power-system TEF is based on classical models, the results from simulation studies of a real system (46 generators and 230 buses) with complex models show that the optimal reclosing time calculated using TEF can be used effectively.

Progress is reported on understanding the interfacial processes that influence the surface treatment and finishing of aluminium and its alloys for practical application, i.e. in the aerospace sector. Using model and commercial alloys, the effects of alloying elements in the matrix and as separate phases on the anodising behaviour may be separated. The insight gained enables informed control of the anodizing conditions for the tailoring of porous anodic film growth in environmentally-friendly electrolytes for protection of the aerospace alloy substrate; further outer, open pore morphologies may also be readily developed for adhesive bonding applications, whilst maintaining protection of the alloy. Progressing further, anodizing conditions have been developed that offer the required control, but with much reduced energy costs and carbon footprint; the previous have been assisted by rapid screening using electrochemical approaches.

AbstractNitrous oxide (N2O) is a potent greenhouse gas and causes stratospheric ozone depletion. While the emissions of N2O from soil are widely recognized, recent research has shown that terrestrial plants may also emit N2O from their leaves under controlled laboratory conditions. However, it is unclear whether foliar N2O emissions are universal across varying plant taxa, what the global significance of foliar N2O emissions is, and how the foliage produces N2O in situ. Here we investigated the abilities of 25 common plant taxa, including trees, shrubs and herbs, to emit N2O under in situ conditions. Using 15N isotopic labeling, we demonstrated that the foliage‐emitted N2O was predominantly derived from nitrate. Moreover, by selectively injecting biocide in conjunction with the isolating and back‐inoculating of endophytes, we demonstrated that the foliar N2O emissions were driven by endophytic bacteria. The seasonal N2O emission rates ranged from 3.2 to 9.2 ng N2O–N g−1 dried foliage h−1. Extrapolating these emission rates to global foliar biomass and plant N uptake, we estimated global foliar N2O emission to be 1.21 and 1.01 Tg N2O–N year−1, respectively. These estimates account for 6%–7% of the current global annual N2O emission of 17 Tg N2O–N year−1, indicating that in situ foliar N2O emission is a universal process for terrestrial plants and contributes significantly to the global N2O inventory. This finding highlights the importance of measuring foliar N2O emissions in future studies to enable the accurate assigning of mechanisms and the development of effective mitigation.

Bike-sharing schemes have dramatically expanded in recent years and it now can be seen in more than 28 countries. Especially in the European countries, people consider riding a bike as a healthy, environment-friendly and low cost travel mode. This paper aims to address the current issues within “smart” bike-sharing project by applying project management approaches. The focus is on the perspective of design management, and use of agile style to conduct the whole phases of project. Meanwhile, the bike-sharing project plays a very important role in the city's transportation system in cities, and from the perspective of urban development, how this project can integrate into the city's intelligent transportation system is worth exploring as well.

AbstractIn order to avoid autoreclosure onto a permanent fault, a new numerical algorithm for fault type determination is presented. It estimates the fault distance, as well, and can be utilized in the field of distance protection. The new approach, mathematical model and the solution for the earthless faults is given. For the purpose of unknown fault distance and arc voltage amplitude estimation, the Least Error Squares Method is used. The new algorithm is tested through numerous computer simulations and in the laboratory environment.

AbstractExtreme weather events can have strong negative impacts on species survival and community structure when surpassing lethal thresholds. Extreme, short‐lived, winter warming events in the Arctic rapidly melt snow and expose ecosystems to unseasonably warm air (for instance, 2–10 °C for 2–14 days) but upon return to normal winter climate exposes the ecosystem to much colder temperatures due to the loss of insulating snow. Single events have been shown to reduce plant reproduction and increase shoot mortality, but impacts of multiple events are little understood as are the broader impacts on community structure, growth, carbon balance, and nutrient cycling. To address these issues, we simulated week‐long extreme winter warming events – using infrared heating lamps and soil warming cables – for 3 consecutive years in a sub‐Arctic heathland dominated by the dwarf shrubsEmpetrum hermaphroditum, Vaccinium vitis‐idaea(both evergreen) andVaccinium myrtillus(deciduous). During the growing seasons after the second and third winter event, spring bud burst was delayed by up to a week forE. hermaphroditumandV. myrtillus, and berry production reduced by 11–75% and 52–95% forE. hermaphroditumandV. myrtillus, respectively. Greater shoot mortality occurred inE. hermaphroditum(up to 52%),V. vitis‐idaea(51%), andV. myrtillus(80%). Root growth was reduced by more than 25% but soil nutrient availability remained unaffected. Gross primary productivity was reduced by more than 50% in the summer following the third simulation. Overall, the extent of damage was considerable, and critically plant responses were opposite in direction to the increased growth seen in long‐term summer warming simulations and the ‘greening’ seen for some arctic regions. Given the Arctic is warming more in winter than summer, and extreme events are predicted to become more frequent, this generates large uncertainty in our current understanding of arctic ecosystem responses to climate change.