910 research outputs found

    Cycle life of lithium ion batteries after flash cryogenic freezing

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    Growing global sales of electric vehicles (EVs) are raising concerns about the reverse logistics challenge of transporting damaged, defective and waste lithium ion battery (LIB) packs. The European Union Battery Directive stipulates that 50% of LIBs must be recycled and EV manufacturers are responsible for collection, treatment and recycling. The International Carriage of Dangerous Goods by Road requirement to transport damaged or defective LIB packs in approved explosion proof steel containers imposes expensive certification. Further, the physical weight and volume of LIB packaging increases transport costs of damaged or defective packs as part of a complete recycling or repurposing strategy. Cryogenic flash freezing (CFF) removes the possibility of thermal runaway in LIBs even in extreme abuse conditions. Meaning damaged or defective LIBs may be transported safely whilst cryogenically frozen. Herein, LIBs are cycled until 20% capacity fade to establish that CFF does not affect electrical performance (energy capacity and impedance) during ageing. This is demonstrated on two different cell chemistries and form factors. The potential to remanufacture or reuse cells/modules subjected to CFF supports circular economy principles through extending useful life and reducing raw material usage. Thereby improving the environmental sustainability of transitioning from internal combustion engines to EVs

    Accelerated internal resistance measurements of lithium-ion cells to support future end-of-life strategies for electric vehicles

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    Industrial and academic communities have embarked on investigating the sustainability of vehicles that contain embedded electrochemical energy storage systems. Circular economy strategies for electric vehicle (EV) or hybrid electric vehicle (HEV) battery systems are underpinned by implicit assumptions about the state of health (SOH) of the battery. The internal resistance of battery systems is the essential property for determining available power, energy efficiency, and heat generation. Consequently, precise measurement is crucial to estimate the SOH; however, the international standards and best practice guides that exist to define the measurements include long preconditioning and rest times that make the test duration prohibitive. The aim of this research is to critically evaluate whether test duration times for internal resistance measurements can be reduced to values that may facilitate further end-of-life (EOL) options. Results reveal a newly developed technique using pulse-multisines is two to four times faster to perform when compared to the standard protocol whilst maintaining accuracy for battery electric vehicle (BEV) and HEV cells, respectively. This novel method allows different stakeholders to rank the relative importance of test accuracy verses experimental test time when categorising used Li-ion cells for different EOL applications. View Full-Tex

    Supporting the externalisation of thinking in criminal intelligence analysis

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    At the end of the criminal intelligence analysis process there are relatively well established and understood approaches to explicit externalisation and representation of thought that include theories of argumentation, narrative and hybrid approaches that include both of these. However the focus of this paper is on the little understood area of how to support users in the process of arriving at such representations from an initial starting point where little is given. The work is based on theoretical considerations and some initial studies with end users. In focusing on process we discuss the requirements of fluidity and rigor and how to gain traction in investigations, the processes of thinking involved including abductive, deductive and inductive reasoning, how users may use thematic sorting in early stages of investigation and how tactile reasoning may be used to externalize and facilitate reasoning in a productive way. In the conclusion section we discuss the issues raised in this work and directions for future work

    How analysts think: how do criminal intelligence analysts recognise and manage significant information?

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    The Criminal Intelligence Analyst's role is to create exhibits which are relevant, accurate and unbiased. Exhibits can be used as input to assist decision-making in intelligence-led policing. It may also be used as evidence in a court of law. The aim of this study was to determine how Criminal Intelligence Analysts recognise and manage significant information as a method to determine what is relevant for their attention and for the creation of exhibits. This in turn may provide guidance on how to design and incorporate loose and flexible argumentation schemas into sense-making software. The objective is to be informed on how to design software, which affords Criminal Intelligence Analysts with the ability to effortlessly determine the relevance of information, which subsequently could assist with the process of assessing and defending the quality of exhibits

    Understanding 3D mid-air hand gestures with interactive surfaces and displays: a systematic literature review

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    3D gesture based systems are becoming ubiquitous and there are many mid-air hand gestures that exist for interacting with digital surfaces and displays. There is no well defined gesture set for 3D mid-air hand gestures which makes it difficult to develop applications that have consistent gestures. To understand what gestures exist we conducted the first comprehensive systematic literature review on mid-air hand gestures following existing research methods. The results of the review identified 65 papers where the mid-air hand gestures supported tasks for selection, navigation, and manipulation. We also classified the gestures according to a gesture classification scheme and identified how these gestures have been empirically evaluated. The results of the review provide a richer understanding of what mid-air hand gestures have been designed, implemented, and evaluated in the literature which can help developers design better user experiences for digital interactive surfaces and displays

    Peel and peel again

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    Aim: To determine if the internal limiting membrane (ILM) was present in the epiretinal membrane (ERM) when we deliberately tried to perform a "double peel" for macular pucker. Methods: Pars-plana vitrectomy and a "double peel" were carried out. The ERM and ILM were stained with Trypan Blue and peeled separately over the same area. The amount of ERM present in ILM specimens and the amount of ILM present in ERM specimens were evaluated by histological examination. Results: Seventeen eyes in 17 patients were included. It was possible to double peel in all cases. Five of 17 ERM specimens (29%) contained ILM fragments. When ILM was present on the ERM, it represented less than 50% of the sample. One ILM specimen was lost as result of an administrative error; of the remaining 16 specimens, residual ERM was found in six, and cellular remnants were observed on the vitreous surface in a further six of the ILMs. Clinically, no recurrence of ERM was found. Conclusion: ILM was present in some ERM specimens seemingly over the same area that an intact ILM was subsequently peel. We speculate that the ILM in the ERM represent a secondary basement membrane and that the surgical plane of dissection for most ERM peel is between the ERM and the native ILM, making it feasible to double peel routinely.published_or_final_versio

    Finding needles in haystacks: linking scientific names, reference specimens and molecular data for Fungi

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    DNA phylogenetic comparisons have shown that morphology-based species recognition often underestimates fungal diversity. Therefore, the need for accurate DNA sequence data, tied to both correct taxonomic names and clearly annotated specimen data, has never been greater. Furthermore, the growing number of molecular ecology and microbiome projects using high-throughput sequencing require fast and effective methods for en masse species assignments. In this article, we focus on selecting and re-annotating a set of marker reference sequences that represent each currently accepted order of Fungi. The particular focus is on sequences from the internal transcribed spacer region in the nuclear ribosomal cistron, derived from type specimens and/or ex-type cultures. Re-annotated and verified sequences were deposited in a curated public database at the National Center for Biotechnology Information (NCBI), namely the RefSeq Targeted Loci (RTL) database, and will be visible during routine sequence similarity searches with NR_prefixed accession numbers. A set of standards and protocols is proposed to improve the data quality of new sequences, and we suggest how type and other reference sequences can be used to improve identification of Fungi

    A hierarchy of factors influence discontinuous gas exchange in the grasshopper Paracinema tricolor (Orthoptera: Acrididae)

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    The evolutionary origin and maintenance of discontinuous gas exchange (DGE) in tracheate arthropods are poorly understood and highly controversial. We investigated prioritization of abiotic factors in the gas exchange control cascade by examining oxygen, water and haemolymph pH regulation in the grasshopper Paracinema tricolor. Using a full-factorial design, grasshoppers were acclimated to hypoxic or hyperoxic (5% O2, 40% O2) gas conditions, or dehydrated or hydrated, whereafter their CO2 release was measured under a range of O2 and relative humidity (RH) conditions (5%, 21%, 40% O2 and 5%, 60%, 90% RH). DGE was significantly less common in grasshoppers acclimated to dehydrating conditions compared with the other acclimations (hypoxia, 98%; hyperoxia, 100%; hydrated, 100%; dehydrated, 67%). Acclimation to dehydrating conditions resulted in a significant decrease in haemolymph pH from 7.0±0.3 to 6.6±0.1 (mean ± s.d., P=0.018) and also significantly increased the open (O)-phase duration under 5% O2 treatment conditions (5% O2, 44.1±29.3 min; 40% O2, 15.8±8.0 min; 5% RH, 17.8±1.3 min; 60% RH, 24.0±9.7 min; 90% RH, 20.6±8.9 min). The observed acidosis could potentially explain the extension of the O-phase under low RH conditions, when it would perhaps seem more useful to reduce the O-phase to lower respiratory water loss. The results confirm that DGE occurrence and modulation are affected by multiple abiotic factors. A hierarchical framework for abiotic factors influencing DGE is proposed in which the following stressors are prioritized in decreasing order of importance: oxygen supply, CO2 excretion and pH modulation, oxidative damage protection and water savings
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