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High Voltage 2019年第4期4卷 316-323页

作者： Mohammed Amer jeff Laninga William McDermid David R.Swatek Behzad Kordi Department of Electrical and Computer Engineering University of Manitoba75 Chancellor's CircleWinnipegManitobaCanada R3T 5V6 Manitoba Hydro WinnipegManitobaCanada R3M 3T1

This research provides conclusions that can partially cover the lack of knowledge related to the effects of ambient atmospheric conditions on DC electric power *** polymer insulating materials are used for completing this research *** a climate chamber,the relative humidity is controlled and adjusted from 20%to 80%***,the samples are charged with positive or negative charges by applying±20 kV to the corona-generating ring of *** surface potential is measured using an electrostatic voltmeter and is converted into surface charge density later by applying the probe response matrix *** pre-charged samples are then stressed with high-voltage negative or positive DC values inside the climate chamber over a range of controlled values of the surrounding air humidity until flashover takes *** space charges,which can drift in the air gap to reach the solid surface,are highly affected by the level of the relative humidity of the surrounding ***,increasing humidity results in a reduction of the DC flashover inception voltage and a shorter time to flashover regardless of the voltage ***,the positive or negative flashover inception voltage of both materials increases with pre-deposited negative charges while it decreases with pre-deposited positive charges.

关键词： charges flash humidity

Coastal eutrophication, land use changes and Ceratium furca (Dinophyceae) blooms in Pago Pago Harbor, American Samoa 2007-2009

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Chinese Journal of Oceanology and Limnology 2011年第4期29卷 790-794页

作者： Steve L. MORTON Andrew SHULER jeff PATERNOSTER Sharon FANOLUA Don VARGO NOAA/National Ocean Service Marine Biotoxins Program Charleston SC 29412 USA American Samoa Community College Community and Natural Resources Pago Pago American Samoa 96799 USA

The bloom forming dinoflagellate, Ceratium furca, has been linked with coastal eutrophication worldwide in tropical and subtropical locations. During the summer of 2007, an unusual 6-month long bloom of C. furca was observed in Pago Pago Harbor, Tutuila Island, American Samoa. Incidents of dinoflagellate blooms in this area have not been previously reported. The bloom was first reported in May and dissipated in November 2007. In February-March 2009, a similar C. furca bloom was observed. During both blooms, no fish mortality events were reported. Maximum cell counts were observed on September 20, 2007 at 9 200 cell/mL. At this time, total nitrogen was measured at 1.2 mg/L while total phosphate was below detection limits. Changes in land use practices may have been the primary driver of these blooms. Intense fertilization of athletic fields coupled with ineffective management strategies is hypothesized to have a direct link to the increase in nutrients found in the Pago Pago Harbor and may have been the trigger for the initialization of these blooms. During 2008, the fields were not used due to an infestation of the fire ant, Solenopsis geminata. Once controlled, the fields were opened again in 2009 and fertilizers were applied in January, a month before the bloom was observed.

关键词： eutrophication American Samoa Ceratium furca

Funnel testing in webpage optimisation:representation,design and analysis

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Statistical Theory and Related Fields 2017年第1期1卷 3-14页

作者： Heng Su C.F.jeff Wu School of Industrial and Systems Engineering Georgia Institute of TechnologyWells Fargo BankCharlotteNCUSA

When optimizingwebpages in order to achieve the best conversion rate,the traditional approach is to isolate and analyze themseparately through a sequence of *** thispaper,wepropose a new framework to study a systemofwebpages simultaneously through the use of directed graph,fractional factorial design and simple optimization *** illustrative example shows that such complicated web systems can be easily studied and optimized by using the proposed methodology.

关键词： Conversion rate optimization webgraph factorial design design of experiment

A rare case of anal tumor: Anal carcinosarcoma

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World Journal of Gastrointestinal Oncology 2010年第12期2卷 446-448页

作者： Christos Mikropoulos Timothy Williams Lamios Munthali jeff Summers Kent Oncology Center Maidstone HospitalHermitage LaneKentME16 9QQUnited Kingdom Kent Oncology Center Maidstone HospitalHermitage LaneKentME16 9QQUniteCASE REPORTd Kingdom

Sarcomatoid carcinoma is a rare tumor with a poor prognosis,otherwise known as *** origin is very rare and only a limited number of anal carcinosarcomas have been reported in the *** management of this rare cancer type is *** aim of this case report was to conf irm that by combining treatment modalities we can achieve long disease free *** chemoradiotherapy led to a good partial response and this was followed by a consolidation surgical endo-anal excision.

关键词： Carcinosarcoma Spindle cell Chemoradio-therapy Endo-anal excision Anal tumour

Concept development and testing of the UK’s first hydrogenhybrid train(HydroFLEX)

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Railway Engineering Science 2021年第3期29卷 248-257页

作者： Charles Calvert jeff Allan Peter Amor Stuart Hillmansen Clive Roberts Paul Weston Birmingham Centre for Railway Research and Education School of EngineeringUniversity of BirminghamEdgbastonBirmingham B152TTUK jeff Vehicles Ltd BeavercreekUSA

In October 2018,Porterbrook and the University of Birmingham announced the HydroFLEX project,to demonstrate a hydrogen-hybrid modified train atRail Live *** concept of modifying a Class 319 Electric Multiple Unit was developed,with equipment including a fuel cell stack,traction battery,24 V control system and hydrogen storage elements to be mounted inside one of the *** was followed by procurement of a fuel cell stack,traction batteries,and control equipment,which was then installed inside the train,being fixed to the seat *** substantial change from the concept was the provision of considerably more hydrogen storage than the minimum necessary,providing the train with more potential to be further modified to allow for higher speed mainline *** the Rail Live exhibition where HydroFLEX was demonstrated,numerous modifications were performed to increase the reliability and power of the HydroFLEX train,primarily concerned with modifying the base train logic,with the aim of a successfulmainline *** this effort was a multitude of documentation concerning safety,operations,and approvals to gain approvals from the relevant approvals *** project demonstrated the feasibility of using hydrogen fuel cells as an autonomous fuel for railway propulsion systems,which has the potential for full decarbonisation.

关键词： Hydrogen Fuel cell Hybrid Systems engineering

Variability scaling and capacity planning in Covid-19 pandemic

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Fundamental Research 2023年第4期3卷 627-639页

作者： L.jeff Hong Guangwu Liu Jun Luo Jingui Xie School of Management and School of Data Science Fudan UniversityShanghai 200433China College of Business City University of Hong KongKowloon TongHong Kong 999077China Antai College of Economics and Management Shanghai Jiao Tong UniversityShanghai 200030China School of Management Technical University of MunichHeilbronn 74076Germany Munich Data Science Institute Technical University of MunichMunich 80333Germany

Capacity planning is a very important global challenge in the face of Covid-19 *** order to hedge against the fluctuations in the random demand and to take advantage of risk pooling effect,one needs to have a good understanding of the variabilities in the demand of ***,Covid-19 predictive models that are widely used in capacity planning typically often predict the mean values of the demands(often through the predictions of the mean values of the confirmed cases and deaths)in both the temporal and spatial *** seldom provide trustworthy prediction or estimation of demand variabilities,and therefore,are insufficient for proper capacity *** by the literature on variability scaling in the areas of physics and biology,we discovered that in the Covid-19 pandemic,both the confirmed cases and deaths exhibit a common variability scaling law between the average of the demand μ and its standard deviationσ,that is,σ ∝ μ^(β),where the scaling parameterμis typically in the range of 0.65 to 1,and the scaling law exists in both the temporal and spatial *** on the mechanism of contagious diseases,we further build a stylized network model to explain the variability scaling *** finally provide simple models that may be used for capacity planning in both temporal and spatial dimensions,with only the predicted mean demand values from typical Covid-19 predictive models and the standard deviations of the demands derived from the variability scaling law.

关键词： Covid-19 Capacity planning Variability scaling Demand aggregation Network model Risk pooling effect

Pregnancy in Patients with Shone Complex: A Single-Center Case Series

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Congenital Heart Disease 2022年第2期17卷 147-160页

作者： Rachel Gardner Emily Durbak Rachael Baird Katherine Singh jeff Chapa David Majdalany Department of Cardiology Cleveland ClinicCleveland44195USA Department of Obstetrics Cleveland ClinicCleveland44195USA Department of Cardiology Mayo ClinicPhoenix85054USA

Background:There is limited literature written on the course and outcomes for pregnant mothers with Shone ***:We describe a case series of five pregnancies in four women with Shone complex within a multidisciplinary cardio-obstetrics clinic from 2016–***:Maternal age ranged from 21–39 *** patients had preserved left ventricular function while one had moderately decreased *** age at presentation ranged from 6–15 *** were three successful pregnancies(mean gestational age=37 weeks,range 35–39 weeks)with one patient accounting for two unsuccessful *** infants were delivered via Cesarean *** infant required a NICU stay,but all other infants delivered were ***:Patients with Shone complex can have successful pregnancies although complications can occur for both the mother and the *** prenatal care,coordinated and consistent management during pregnancy,and tertiary care support can promote positive maternal and fetal outcomes.

关键词： Shone complex pregnancy cardiac disease in pregnancy women’s cardiovascular health

The need for a new framework for the economic evaluation of health services in a national health scheme

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Health 2010年第9期2卷 1120-1133页

作者： jeff R. Richardson John McKie Kompal Sinha Centre for Health Economics Monash University

The normative theory of economic evaluation and its welfare theoretic basis are deeply problematical and result in recommendations which are potentially unfair. The root cause of the problem is the set of assumptions behind the theory which posit behaviours and motivations that are not universal, and which exclude other behaviours and motivations that are potentially important. As falsification of assumptions may be evaded indefinitely this paper presents an alternative critique. We commence with six an- omalies with the theory which are attributable to the assumptions. The first three—the net present value criterion, the willingness to pay criterion and moral hazard—arise from welfare theory. The remaining three are associated with the present definition of cost, the concept of efficiency and the omission of sharing, which are common to most economic evaluation. We argue that these anomalies are indicative of a defective core theory and that they are equivalent to observations that conflict with a positive theory. In the final section we outline and illustrate a more general framework for decision making that is capable of overcoming the ano- malies we discuss.

关键词： Economic Evaluation Economic Costs Welfare Theory Empirical Ethics Cost Benefit Analysis

Emergency evacuation system for mines

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Journal of Coal Science & Engineering(China) 2011年第3期17卷 281-284页

作者： QIAN Qing-yi BUDIMAN jeff SHEN Jay Department of Civil Architecture ＆ Environmental Engineering Illinois Institute of Technology Chicago 1L60616 USA

There are many potential hazards in the underground mining these include fire, explosion, inundation, roof collapse, toxic gases, chemical pollution, etc. Over past centuries, in US alone, more than 100 000 miners lost their life in different accidents. The primary safety methods used in underground mines concentrate on the monitoring of the hazardous gases, fire detection and ventilation. Using advanced instruments and monitoring techniques have significantly reduced the accidents in the modem mines. However despite the advancement of these monitoring facilities, accidents still occur in underground mining annually in the world, and many miners were killed because they were trapped and unable to escape due to blocked of exit access. Described a new development for the emergency evacuation system in underground mines and analyzed the advantages and disadvantages of the system. It is expected that the new system will greatly improve the emergency exit methods and save more lives in the future.

关键词： evacuation system mine shaft elevators shaft lining

Development of a field enhanced photocatalytic device for biocide of coliform bacteria

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Journal of Environmental Sciences 2016年第6期28卷 38-44页

作者： jeff M.Huber Krista L.Carlson Otakuye Conroy-Ben Mano Misra Swomitra K.Mohanty Departments of Civil Engineering University of Utah Departments of Metallurgical Engineering University of Utah Departments of Chemical Engineering University of Utah

A field enhanced flow reactor using bias assisted photocatalysis was developed for bacterial disinfection in lab-synthesized and natural waters. The reactor provided complete inactivation of contaminated waters with flow rates of 50 mL/min. The device consisted of titanium dioxide nanotube arrays, with an externally applied bias of up to 6 V. Light intensity, applied voltage, background electrolytes and bacteria concentration were all found to impact the device performance. Complete inactivation of Escherichia coli W3110（- 8 × 10^3CFU/mL） occurred in 15 sec in the reactor irradiated at 25 mW/cm^2 with an applied voltage of 4 V in a 100 ppm NaCl solution. Real world testing was conducted using source water from Emigration Creek in Salt Lake City, Utah. Disinfection of natural creek water proved more challenging, providing complete bacterial inactivation after 25 sec at 6 V. A reduction in bactericidal efficacy was attributed to the presence of inorganic and organic species, as well as the increase in robustness of natural bacteria.

关键词： Titanium dioxide Nanotubes Immobilized Photocatalysis Escherichia coli Inactivation