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High rate (<100kW) electric vehicle chargers (HREVCs) are crucial for achieving the benefits of reduced CO 2 and particulate emissions promised by electric vehicles by enabling journey distances greater than the range of the vehicle. A method for predicting the expected demand pattern at these HREVCs is presented in this paper. This is critical to planning a network of chargers. This novel method uses freely available traffic flow data and travel patterns extracted from the open street map combined with a novel EV battery capacity prediction method, to find future HREVC usage patterns in the UK and their dependence on location and EV characteristics. This planning method can be replicated to find HREVC power demand for any location on the strategic road network in the UK and can be used in analysis of the role of high rate EV charging in the wider energy system. Index Terms Vehicles, Battery chargers, Power system modeling, Load modeling I. INTRODUCTION The use of fossil fuel vehicles contributes to climate change through the release of CO 2 , nitrous oxides and unburnt hydrocarbons, and causes harmful levels of pollution to be present in cities around the world [1]. The removal of fossil fuels from the transport industry is therefore of clear importance. One method to achieve this which is currently gaining traction is the introduction of electric vehicles (EVs). EVs have the advantage of zero local gaseous emissions and improved

A transformer-less Buck-Boost direct current–direct current (DC–DC) converter in use for the fast charge of electric vehicles, based on powerful high-voltage isolated gate bipolar transistor (IGBT) modules is analyzed, designed and experimentally verified. The main advantages of this topology are: simple structure on the converter’s power stage; a wide range of the output voltage, capable of supporting contemporary vehicles’ on-board battery packs; efficiency; and power density accepted to be high enough for such a class of hard-switched converters. A precise estimation of the loss, dissipated in the converter’s basic modes of operation Buck, Boost, and Buck-Boost is presented. The analysis shows an approach of loss minimization, based on switching frequency reduction during the Buck-Boost operation mode. Such a technique guarantees stable thermal characteristics during the entire operation, i.e., battery charge cycle. As the Buck-Boost mode takes place when Buck and Boost modes cannot support the output voltage, operating as a combination of them, it can be considered as critically dependent on the characteristics of the semiconductors. With this, the necessary duty cycle and voltage range, determined with respect to the input-output voltages and power losses, require an additional study to be conducted. Additionally, the tolerance of the applied switching frequencies for the most versatile silicon-based powerful IGBT modules is analyzed and experimentally verified. Finally, several important characteristics, such as transients during switch-on and switch-off, IGBTs’ voltage tails, critical duty cycles, etc., are depicted experimentally with oscillograms, obtained by an experimental model.

We describe three contributions for distributed resource allocation in scienti c applications. First, we present an abstract model in which di erent resources are represented as tokens of di erent colors processes acquire resources by acquiring these tokens. Second, we present distributed scheduling algorithms that allow m ultiple resource managers to determine custom policies to control allocation of the tokens representing their particular resources. These algorithms allow m ultiple resource managers, each with its own resource management policy, to collaborate in providing resources for the whole system. Third, we present a n i mplementation of a distributed resource scheduling algorithm framework using our abstract model. This implementation uses Infospheres, which are Internet communication packages written in Java, and shows the bene ts of distributing the task of resource allocation to multiple resource managers. Hierarchical session infrastructure.

Despite progress in the treatment of acute lymphoblastic leukemia (ALL), T-cell ALL (T-ALL) has limited treatment options, particularly in the setting of relapsed/refractory disease. Using an unbiased genome-scale CRISPR-Cas9 screen we sought to identify pathway dependencies for T-ALL which could be harnessed for therapy development. Disruption of the one-carbon folate, purine and pyrimidine pathways scored as the top metabolic pathways required for T-ALL proliferation. We used a recently developed inhibitor of SHMT1 and SHMT2, RZ-2994, to characterize the effect of inhibiting these enzymes of the one-carbon folate pathway in T-ALL and found that T-ALL cell lines were differentially sensitive to RZ-2994, with the drug inducing a S/G2 cell cycle arrest. The effects of SHMT1/2 inhibition were rescued by formate supplementation. Loss of both SHMT1 and SHMT2 was necessary for impaired growth and cell cycle arrest, with suppression of both SHMT1 and SHMT2 inhibiting leukemia progression in vivo. RZ-2994 also decreased leukemia burden in vivo and remained effective in the setting of methotrexate resistance in vitro. This study highlights the significance of the one-carbon folate pathway in T-ALL and supports further development of SHMT inhibitors for treatment of T-ALL and other cancers.

Abstract:The purpose of the presented flyback converter is to equalise the voltage between the cells in a series string within a battery pack providing an active cell-balancing system. This would be an important part of a battery management system (BMS) for charging li-ion batteries in electric vehicles. The converter is based on primary side current sensing, where the conventional feedback circuit is omitted. The purpose of this converter is to improve efficiency by decreasing losses and to increase battery power density by decreasing the number of elements which constitute the power electronics; these are important factors for the future development of electric vehicle battery packs. Analysis of the circuit and the design procedure of the DC-DC flyback converter with primary current sensing is presented in this paper. Finally, several experimental converters have been built and tested to validate the authors' approach.