3,048 research outputs found

    Transmission Expansion Planning Considering Energy Storage

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    In electricity transmission networks, energy storage systems (ESS) provide a means of upgrade deferral by smoothing supply and matching demand. We develop a mixed integer programming (MIP) extension to the transmission network expansion planning (TEP) problem that considers the installation and operation of ESS as well as additional circuits. The model is demonstrated on the well known Garver's 6-bus and IEEE 25-bus test circuits for two 24 hour operating scenarios; a short peak, and a long peak. We show optimal location and capacity of storage is sensitive not only to cost, but also variability of demand in the network

    Contributions in the field of palaeopalynology at the Bernard Price Institute, past, present and future

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    Main articleA brief chronological summary of the palynological research carried out by students and past members of the staff at the Bernard Price Institute for Palaeontological Research is presented. The contribution that each of these studies has made to the understanding of stratigraphic relationships in the southern African region is highlighted. A correlation chart of palynological biozones documented from South African localities is presented (Table 1).Non

    Multi-objective integer programming: An improved recursive algorithm

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    This paper introduces an improved recursive algorithm to generate the set of all nondominated objective vectors for the Multi-Objective Integer Programming (MOIP) problem. We significantly improve the earlier recursive algorithm of \"Ozlen and Azizo\u{g}lu by using the set of already solved subproblems and their solutions to avoid solving a large number of IPs. A numerical example is presented to explain the workings of the algorithm, and we conduct a series of computational experiments to show the savings that can be obtained. As our experiments show, the improvement becomes more significant as the problems grow larger in terms of the number of objectives.Comment: 11 pages, 6 tables; v2: added more details and a computational stud

    Generating and evaluating a ranked candidate gene list for potential vertebrate heart field regulators

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    The vertebrate heart develops from two distinct lineages of cardiomyocytes that arise from the first and second heart fields (FHF and SHF, respectively). The FHF forms the primitive heart tube, while adding cells from the SHF allows elongation at both poles of the tube. Initially seen as an exclusive characteristic of higher vertebrates, recent work has demonstrated the presence of a distinct FHF and SHF in lower vertebrates, including zebrafish. We found that key transcription factors that regulate septation and chamber formation in higher vertebrates, including Tbx5 and Pitx2, influence relative FHF and SHF contributions to the zebrafish heart tube. To identify molecular modulators of heart field migration, we used microarray-based expression profiling following inhibition of tbx5a and pitx2ab in embryonic zebrafish (Mosimann & Panakova, et al, 2015; GSE70750). Here, we describe in more detail the procedure used to process, prioritize, and analyze the expression data for functional enrichment

    Violence, uncertainty, and resilience among refugee women and community workers: An evaluation of gender-based violence case management services in the Dadaab refugee camps.

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    Reports of gender-based violence (GBV) are common in camps for refugees and displaced populations. In the Dadaab refugee camps in north-eastern Kenya, the International Rescue Committee (IRC) and CARE International (CARE) implement programmes that aim to both respond to and prevent GBV. A cornerstone of this work has been to train refugees, known as refugee community workers, to deliver aspects of GBV prevention and response work in order to develop a broader implementation of traditional GBV outreach, community mobilisation, and case management. To date, there has been limited rigorous research on this broader GBV case management plus task sharing approach in the context of a refugee camp setting. To address this key gap in evidence, the London School of Hygiene and Tropical Medicine (LSHTM) and the African Population and Health Research Centre (APHRC), in collaboration with IRC and CARE, have sought to assess this model to understand its feasibility, acceptability, and influence among female survivors of GBV accessing care. Data for this study, funded by UK aid, were collected in the Dadaab refugee camps between 2014 and 2017, which coincided with a temporary decision to close the camp and repatriate Somali refugees. The research confirms the magnitude and complexity of the violence that women and girls experience in the camps in Dadaab. In the year leading up to this study, 47% of women accessing the GBV centres for case management reported experiencing intimate partner violence and 39% reported experiencing non-partner violence. In addition, the study highlights the specific risks, challenges, opportunities and rewards experienced by refugee community workers in their dual role of community members and GBV activists living side-by-side with survivors and perpetrators of violence. Solely related to their work as GBV caseworkers, one in three refugee community workers reported experiencing non-partner violence in the last 12 months. Despite this, 93% of refugee community workers stated their work was rewarding or extremely rewarding. The majority of women (82%) accessing services reported that their interactions with refugee community workers had a positive effect, and that working with them was useful. However, having refugees deliver services to their own community was not without its challenges, and survivors raised issues on confidentiality, mistranslations, and perceived biases on clan differences. The study also provides an insight into the importance of contextual factors in case management, and the impact of the announcement of the (now-delayed) camp closure in Dadaab. Priorities of both the camp population and service providers (GBV and referral services) shifted greatly during this time of uncertainty and affected when and how women were accessing services

    (4-Hydr­oxy-3-nitro­benz­yl)methyl­ammonium chloride

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    The title compound, C8H11N2O3 +·Cl−, was synthesized as an inter­mediate in the development of a new sugar sensor. The structure displays N—H⋯Cl and O—H⋯O hydrogen bonding, as well as weak O—H⋯Cl inter­actions and π–π stacking (3.298 Å). There are two formula units in the asymmetric unit

    Non‐native species have multiple abundance–impact curves

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    The abundance–impact curve is helpful for understanding and managing the impacts of non‐native species. Abundance–impact curves can have a wide range of shapes (e.g., linear, threshold, sigmoid), each with its own implications for scientific understanding and management. Sometimes, the abundance–impact curve has been viewed as a property of the species, with a single curve for a species. I argue that the abundance–impact curve is determined jointly by a non‐native species and the ecosystem it invades, so that a species may have multiple abundance–impact curves. Models of the impacts of the invasive mussel Dreissena show how a single species can have multiple, noninterchangeable abundance–impact curves. To the extent that ecosystem characteristics determine the abundance–impact curve, abundance–impact curves based on horizontal designs (space‐for‐time substitution) may be misleading and should be used with great caution, it at all. It is important for scientists and managers to correctly specify the abundance–impact curve when considering the impacts of non‐native species. Diverting attention from the invading species to the invaded ecosystem, and especially to the interaction between species and ecosystem, could improve our understanding of how non‐native species affect ecosystems and reduce uncertainty around the effects of management of populations of non‐native species.The abundance–impact curve is a useful tool for understanding and managing the impacts of invasive species. Using models based on the impacts of the zebra mussel, I show that a single invasive species can have radically different abundance–impact curves in different habitats. This means that managers must be careful to use the correct abundance–impact curve and that scientists should avoid using space‐for‐time substitution to understand the impacts of invaders.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156222/2/ece36364.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156222/1/ece36364_am.pd
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