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Optimal control and energy storage for DC electric train systems using evolutionary algorithms

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Railway Engineering Science 2021年第4期29卷 327-335页

作者： Sam Nallaperuma David Fletcher robert harrison University of Cambridge CambridgeUK University of Sheffield SheffieldUK

Electrified railways are becoming a popular transport medium and these consume a large amount of electrical *** concerns demand reduction in energy use and peak power demand of railway ***,high transmission losses in DC railway systems make local storage of energy an increasingly attractive *** optimisation framework based on genetic algorithms is developed to optimise a DC electric rail network in terms of a comprehensive set of decision variables including storage size,charge/discharge power limits,timetable and train driving style/trajectory to maximise benefits of energy storage in reducing railway peak power and energy *** results for the considered real-world networks show a reduction of energy consumption in the range 15%–30%depending on the train driving style,and reduced power peaks.

关键词： Autonomous control Intelligent transport systems Energy optimisation DC railway systems Energy regeneration

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Carbon Stock Changes in Soil and Aboveground Biomass from House Lot Development in King County, Washington, USA

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Open Journal of Forestry 2012年第1期2卷 1-8页

作者： Stephen Porder Deborah Lipson robert harrison 不详

Fossil fuel burning and deforestation have driven dramatic increases in atmospheric CO2 since the industrial revolution. However, forests in the northern temperate region sequester a substantial (~0.6 Pg?yr–1) amount of carbon (C), largely through the regrowth of secondary forests that were originally cleared for timber over one hundred years ago. In the United States, however, some regions are approaching a maximum regrowth as forests are cleared again, this time for suburban and exurban development. Here we explore the effects of such development on C stocks in King County, WA, an area with high forest cover but rapid suburban expansion. We measured soil and biomass C on 18 paired-house/forest lots, and found house lots stored ~80 Mg?C?ha–1 less soil C, and between 130 and 280 Mg?C?ha–1 less above-ground biomass C than adjacent forest lots. Combining soil C losses with estimates of C emissions from forest products yields average C emissions of 130 - 280 Mg?C?ha–1, with the majority of losses occurring at the time of lot conversion. As a comparison, suburban dwellers drive ~30% more than city residents, but this increase in annual emissions from increased driving is 1% - 2.5% of the losses of C associated with converting forests to house lots. If forestland conversion in the Seattle area continues apace, in the coming decades C emissions each year from that land-use conversion will equal ~4% of King County’s 2008 C emissions.

关键词： Land-Use Change Carbon Urban Soils Emissions Urban Growth Development

Environmental Risk Imposed by Diverted Flood Waters on Water and Soils in Emergency Retention Basins

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Journal of Environmental Protection 2010年第2期1卷 129-135页

作者： Karl Erich Lindenschmidt robert harrison Martina Baborowski 不详

Emergency retention basins (ERB) are diked enclosures alongside rivers into which water from the main river channel is diverted during extreme floods. If the basins are operated during extreme flooding, two negative environmental impacts may occur: 1) contamination of the soils due to their transport by suspended sediments to the basin and 2) depletion of dissolved oxygen in the basin water. A computer-based methodology is presented which was used to assess the environmental risk exhibited by the operation of an ERB system proposed for the Elbe River in Germany. The August 2002 extreme flood event was used as a test case. For such a flood, the results showed that there is a 77% risk that dissolved oxygen levels fall below 2 mg/L in the water and a 48% chance of exceeding the inspection value of 500 mg zinc/kg in the soil.

关键词： Environmental Risk Inundation Retention Basins Water Quality Contaminated Soils Quasi-2D Model

Measuring Ice Thicknesses along the Red River in Canada Using RADARSAT-2 Satellite Imagery

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Journal of Water Resource and Protection 2010年第11期2卷 923-933页

作者： Karl-Erich Lindenschmidt Gerry Syrenne robert harrison 不详

The spring flood of 2009 in the Red River Valley was exacerbated with severe ice breakup and ice jamming. To assist ice jam mitigation by cutting and breaking up the river ice cover before the flood season and to support the operation of the Red River Floodway, Manitoba Water Stewardship is striving to model the occurrence of ice breakup and simulate the behaviour of ice jamming along the river. An important parameter in ice breakup forecasting is the ice thickness. RADARSAT-2 standard satellite images were collected along the course of the Red River in Manitoba during the 2009-2010 winter to help determine ice thicknesses along the river. Standard images can have transmit-receive polarizations in the horizontal-horizontal (HH) or horizontal-vertical (HV) configurations. Ice thickness measurements were taken in the field during the same time frame when the satellite passed over the Red River Valley. Good correlations were obtained between the HH-backscatter readings and the surveyed ice thicknesses. HV-backscatter readings correlate better with fresh snow depth measurements. Additionally, using same sensor incident angle and flight geometry allows ice thickening rate behavior over the course of the winter to be determined.

关键词： Ice Jams RADARSAT-2 Red River River Ice Thickness Snow Cover Depth

Ice Jam Modelling of the Lower Red River

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Journal of Water Resource and Protection 2012年第1期4卷 1-11页

作者： Karl-Erich Lindenschmidt Maurice Sydor Rick Carson robert harrison 不详

The lower reach of the Red River between Winnipeg and Lake Winnipeg is very prone to ice jam flooding. The one- dimensional ice jam model RIVICE was implemented for this reach to better understand the processes leading to such events and to provide a tool to evaluate strategies for ice jam mitigation. The most downstream portion of this river stretch flows through a delta and marsh system which poses challenges in modelling ice jams in such an area of low-lying topography and river banks. Solutions to overcome these challenges are discussed in this paper and results of one such solution using water abstractions from the main channel are also presented. Abstractions are inserted in the model to represent under-ice leakage from the main channel to side channel storage and diversions (up to 65% in the Red River delta) and spillage into the delta floodplain.

关键词： Ice Jam Modeling Netley Creek Letley-Libau Marsh Red River Delta RIVICE

Amplicon-based metagenomics identified candidate organisms in soils that caused yield decline in strawberry

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Horticulture Research 2015年第1期2卷 201-213页

作者： Xiangming Xu Thomas Passey Feng Wei robert Saville Richard J.harrison East Malling Research East MallingWest MallingKentME196BJUK

A phenomenon of yield decline due to weak plant growth in strawberry was recently observed in non-chemo-fumigated soils,which was not associated with the soil fungal pathogen Verticillium dahliae,the main target of ***-based metagenomics was used to profile soil microbiota in order to identify microbial organisms that may have caused the yield decline.A total of 36 soil samples were obtained in 2013 and 2014 from four sites for metagenomic studies;two of the four sites had a yield-decline problem,the other two did *** than 2000 fungal or bacterial operational taxonomy units(OTUs)were found in these *** abundance of individual OTUs was statistically compared for differences between samples from sites with or without yield decline.A total of 721 individual comparisons were statistically significant–involving 366 unique bacterial and 44 unique fungal *** on further selection criteria,we focused on 34 bacterial and 17 fungal OTUs and found that yield decline resulted probably from one or more of the following four factors:(1)low abundance of Bacillus and Pseudomonas populations,which are well known for their ability of supressing pathogen development and/or promoting plant growth;(2)lack of the nematophagous fungus(Paecilomyces species);(3)a high level of two non-specific fungal root rot pathogens;and(4)wet soil *** study demonstrated the usefulness of an amplicon-based metagenomics approach to profile soil microbiota and to detect differential abundance in microbes.

关键词： soil straw soils

Physical mechanism of “slow light” in stimulated Brillouin scattering

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Frontiers of Optoelectronics 2010年第1期3卷 22-32页

作者： Valeri I.KOVALEV robert G.harrison Nadezhda E.KOTOVA Department of Physics Heriot-Watt University P.N.Lebedev Physical Institute Russian Academy of Sciences

We show from analytical analysis of the basic stimulated Brillouin scattering(SBS) equations in the time domain that the SBS amplification process does not amplify an external Stokes pulse and therefore cannot induce group delay of the Stokes pulse as claimed in the literature. Rather, the delayed output Stokes pulse is the pump radiation reflected by the induced acoustic wave, the amplitude of which determines the rate of the amplification process and time delay of the pulse. The latter is predominantly a consequence of the SBS buildup process determined by the inertia of the acoustic wave *** solutions of the SBS equations in the frequency domain show that spectral broadening of the pump radiation leads to only negligible broadening of the SBS spectral bandwidth and so does not provide an effective means to achieve broadband pulse delay.

关键词： stimulated Brillouin scattering (SBS) pulse delay acoustic wave inertia spectral bandwidth

Lack of hepcidin expression attenuates steatosis and causesfibrosis in the liver

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World Journal of Hepatology 2016年第4期8卷 211-225页

作者： Sizhao Lu robert G Bennett Kusum K Kharbanda Duygu Dee harrison-Findik Department of Biochemistry University of Nebraska Medical CenterOmahaNE 68198-5870United States Division of Endocrinology Department of Internal MedicineUniversity of Nebraska Medical CenterOmahaNE 68198-4130United States Nebraska-Western Iowa VA Health Care System OmahaNE 68105United States Division of Gastroenterology and Hepatology Department of Internal MedicineUniversity of Nebraska Medical CenterOmahaNE 68198-2000United States

AIM: To investigate the role of key iron-regulatory protein, hepcidin in non-alcoholic fatty liver disease(NAFLD). METHODS: Hepcidin(Hamp1) knockout and floxed control mice were administered a high fat and high sucrose(HFS) or a regular control diet for 3 or 7 mo. Steatosis, triglycerides, fibrosis, protein and gene expression in mice livers were determined by histological and biochemical techniques, western blotting and realtime polymerase chain reaction. RESULTS: Knockout mice exhibited hepatic iron accumulation. Despite similar weight gains, HFS feeding induced hepatomegaly in floxed, but not knockout, mice. The livers of floxed mice exhibited higher levels of steatosis, triglycerides and c-Jun N-terminal kinase(JNK) phosphorylation than knockout mice. In contrast, a significant increase in fibrosis was observed in knockout mice livers within 3 mo of HFS administration. The hepatic gene expression levels of sterol regulatoryelement-binding protein-1c and fat-specific protein-27, but not peroxisome proliferator-activated receptoralpha or microsomal triglyceride transfer protein, were attenuated in HFS-fed knockout mice. Knockout mice fed with regular diet displayed increased carnitine palmitoyltransferase-1a and phosphoenolpyruvate carboxykinase-1 but decreased glucose-6-phosphatase expression in the liver. In summary, attenuated steatosis correlated with decreased expression of lipogenic and lipid storage genes, and JNK phosphorylation. Deletion of Hamp1 alleles per se modulated hepatic expression of beta-oxidation and gluconeogenic genes. CONCLUSION: Lack of hepcidin expression inhibits hepatic lipid accumulation and induces early development of fibrosis following high fat intake. Hepcidin and iron may play a role in the regulation of metabolic pathways in the liver, which has implications for NAFLD pathogenesis.

关键词： Hamp Iron Non-alcoholic steatohepatitis Metabolic genes Steatosis non-alcoholic fatty liverdisease Steatohepatitis

Effect of organic acid on Cd toxicityin tomato and bean growth

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Journal of Environmental Sciences 1995年第4期7卷 399-406页

作者： Xue Dongsen robert B. harrison Charles L. Henry(University of Washington , ARIO Seattle . WA 98195 , USA)

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关键词： admium pollution phytotoxicity oxalic acid tomato: bean.

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