scholarly journals Analytical and Measured Effects of Short and Heavy Rail Cars on Railway Bridges in the USA

2021 ◽  
Vol 11 (7) ◽  
pp. 3126
Author(s):  
Anna M. Rakoczy ◽  
Duane E. Otter ◽  
Stephen M. Dick
Keyword(s):  
Unit Length ◽  
Railway Bridges ◽  
The North ◽  
Deck Plate ◽  
The Usa ◽  
Load Effects ◽  
The Difference ◽  
Truss Bridge ◽  
Bridge Spans ◽  
Main Bridge

The overall number of railcars recorded in the North American railcar fleet from 2010 to 2015 increased about 5%; the number of all 130 tonne (286,000 lb) gross weight railcars (heavy axle load (HAL) railcars) increased 19%. The increase in shipments in short railcars increases the loading on railway bridges, especially the 12.8-m railcars, commonly used to ship sand and cement, which is approximately a 25% increase in load per unit length compared to 16.2-m coal cars. Significant differences between maximum effects of shorter railcars and common 16.2-m railcars were predicted in analysis for bridge spans longer than 18.3 m. The differences were more prominent on spans 24.4 m and longer. This study presents analytical and measured effects of freight railcars on a two-span truss bridge, with spans of 61 m and 33.5 m, and a 35-m riveted steel deck plate girder (DPG) bridge. The investigation confirmed that short railcars cause higher load effects on main bridge components: the 35-m riveted steel DPG has 28% higher stresses at mid-span, while in the truss, the difference in stresses depends on the location of the member and ranges from 15 to 35%.

Heavy Axle Load Effects on Fatigue Life of Steel Bridges

2003 ◽  
Vol 1825 (1) ◽  
pp. 38-47 ◽  
Author(s):  
John F. Unsworth
Keyword(s):  
Fatigue Life ◽  
North American ◽  
Steel Bridges ◽  
Class I ◽  
Life Extension ◽  
Railway Bridges ◽  
The Past ◽  
The North ◽  
Safety And Reliability ◽  
Load Effects

Heavy axle railway loads (freight equipment with more than a 100-ton capacity and gross vehicle weights exceeding 263,000 lb) have been introduced extensively on North American Class I freight railroads in the past decade. An overview is presented of the effects of heavy axle loads on the fatigue life of steel bridges in the North American freight railroad infrastructure. Also outlined are life extension and rehabilitation techniques typically used to maintain the safety and reliability of existing steel railway bridges.

scholarly journals Tracking a Coastal Wave Buoy, Lost from the Southern Coast of Jeju Island, Using Lagrangian Particle Modeling

2021 ◽  
Vol 9 (8) ◽  
pp. 795
Author(s):  
Seongbong Seo ◽  
Young-Gyu Park
Keyword(s):  
Japan Sea ◽  
Jeju Island ◽  
East China ◽  
Northwest Pacific ◽  
Southern Coast ◽  
Lagrangian Particle ◽  
The North ◽  
Particle Modeling ◽  
The Usa ◽  
Tracking Model

A coastal wave buoy was lost near Jeju Island, Korea, in late July 2014 and found at Cape Mendocino, USA, in April 2020. The buoy’s journey was simulated with a Lagrangian particle tracking model using surface ocean currents and wind data at 10 m above sea level. Experiments were conducted with windage values of 0, 2, and 4%. Particles were released along the southern coast of Jeju Island from 31 July to 8 August 2014. When the windage was 0 or 2%, most particles reached the northwest Pacific via the East/Japan Sea or East China Sea, respectively. With 4% windage, very few particles entered the North Pacific. Under 0% windage, particles accumulated in the Great Pacific Garbage Patch (GPGP) and never reached the USA. Under 2%, particles were able to escape the GPGP and started to reach the USA coast 2 years and 7 months after the release. The trajectory of the buoy was deduced from the trajectories of particles with a similar travel time. The buoy likely moved to East China and then to the subtropical convergence zone, where it must have circulated for approximately 2 years before being pushed toward Cape Mendocino by the intensified winter westerlies.

scholarly journals A “Smart” Biosensor-Enabled Intravascular Catheter and Platform for Dynamic Delivery of Propofol to “Close the Loop” for Total Intravenous Anesthesia

2021 ◽  
Vol 186 (Supplement_1) ◽  
pp. 370-377
Author(s):  
Edward Chaum ◽  
Ernő Lindner
Keyword(s):  
Real Time ◽  
Drug Distribution ◽  
Population Based ◽  
Pharmacokinetic Data ◽  
Drug Infusion ◽  
Blood Concentrations ◽  
The Usa ◽  
The Difference ◽  
Automated Delivery

ABSTRACT Background Target-controlled infusion anesthesia is used worldwide to provide user-defined, stable, blood concentrations of propofol for sedation and anesthesia. The drug infusion is controlled by a microprocessor that uses population-based pharmacokinetic data and patient biometrics to estimate the required infusion rate to replace losses from the blood compartment due to drug distribution and metabolism. The objective of the research was to develop and validate a method to detect and quantify propofol levels in the blood, to improve the safety of propofol use, and to demonstrate a pathway for regulatory approval for its use in the USA. Methods We conceptualized and prototyped a novel “smart” biosensor-enabled intravenous catheter capable of quantifying propofol at physiologic levels in the blood, in real time. The clinical embodiment of the platform is comprised of a “smart” biosensor-enabled catheter prototype, a signal generation/detection readout display, and a driving electronics software. The biosensor was validated in vitro using a variety of electrochemical methods in both static and flow systems with biofluids, including blood. Results We present data demonstrating the experimental detection and quantification of propofol at sub-micromolar concentrations using this biosensor and method. Detection of the drug is rapid and stable with negligible biofouling due to the sensor coating. It shows a linear correlation with mass spectroscopy methods. An intuitive graphical user interface was developed to: (1) detect and quantify the propofol sensor signal, (2) determine the difference between targeted and actual propofol concentration, (3) communicate the variance in real time, and (4) use the output of the controller to drive drug delivery from an in-line syringe pump. The automated delivery and maintenance of propofol levels was demonstrated in a modeled benchtop “patient” applying the known pharmacokinetics of the drug using published algorithms. Conclusions We present a proof-of-concept and in vitro validation of accurate electrochemical quantification of propofol directly from the blood and the design and prototyping of a “smart,” indwelling, biosensor-enabled catheter and demonstrate feedback hardware and software architecture permitting accurate measurement of propofol in blood in real time. The controller platform is shown to permit autonomous, “closed-loop” delivery of the drug and maintenance of user-defined propofol levels in a dynamic flow model.

scholarly journals Development of a Novel Damage Detection Framework for Truss Railway Bridges Using Operational Acceleration and Strain Response

Vibration ◽  
2021 ◽  
Vol 4 (2) ◽  
pp. 422-445
Author(s):  
Md Riasat Azim ◽  
Mustafa Gül
Keyword(s):  
Damage Detection ◽  
Damage Identification ◽  
Numerical Study ◽  
Damage Index ◽  
Strain Analysis ◽  
Time History ◽  
Principal Component ◽  
Element Model ◽  
Railway Bridges ◽  
Truss Bridge

Railway bridges are an integral part of any railway communication network. As more and more railway bridges are showing signs of deterioration due to various natural and artificial causes, it is becoming increasingly imperative to develop effective health monitoring strategies specifically tailored to railway bridges. This paper presents a new damage detection framework for element level damage identification, for railway truss bridges, that combines the analysis of acceleration and strain responses. For this research, operational acceleration and strain time-history responses are obtained in response to the passage of trains. The acceleration response is analyzed through a sensor-clustering-based time-series analysis method and damage features are investigated in terms of structural nodes from the truss bridge. The strain data is analyzed through principal component analysis and provides information on damage from instrumented truss elements. A new damage index is developed by formulating a strategy to combine the damage features obtained individually from both acceleration and strain analysis. The proposed method is validated through a numerical study by utilizing a finite element model of a railway truss bridge. It is shown that while both methods individually can provide information on damage location, and severity, the new framework helps to provide substantially improved damage localization and can overcome the limitations of individual analysis.

Art book publishing in Canada

1992 ◽  
Vol 17 (3) ◽  
pp. 34-37
Author(s):  
Melva J. Dwyer
Keyword(s):  
Book Publishing ◽  
Book Production ◽  
Government Grants ◽  
The North ◽  
Quebec French ◽  
The Usa ◽  
Publishing Houses ◽  
Added Benefit ◽  
The Cost ◽  
Inuit Peoples

Canadian publishing was inhibited from the beginning by Canada’s colonial origins and dependence on Great Britain and the USA. Few art books were published until quite recently; the relatively small, scattered population, the flooding of the market with British, American and (in Quebec) French books, and limited (at best) or non-existent sales outside Canada continue to be constraining factors. The necessity to include both English and French texts adds to the cost of book production in Canada. The publication of art books, and of exhibition catalogues, depends on the availability of government grants. Publications on the art of the North American Indian and Inuit peoples are an exception, attracting widespread interest and leading in some instances to co-publishing initiatives. In addition to the larger publishing houses, a number of small presses produce occasional art books, thanks to grants and in a few cases with the added benefit of sales abroad achieved through international networking. A government programme of support for Canadian publishing, launched in 1986, is continuing.

Design of the Murray and Wolverine River rail bridges

1984 ◽  
Vol 11 (4) ◽  
pp. 701-708 ◽  
Author(s):  
G. W. Taylor
Keyword(s):  
Single Cell ◽  
Key Words ◽  
Continuous Steel ◽  
Box Girder ◽  
Railway Bridges ◽  
Branch Line ◽  
Steel Box Girder ◽  
Deck Plate ◽  
Bridge Steel

This paper describes the design of the Murray and Wolverine River rail bridges, two of the largest river crossings on British Columbia's Tumbler Ridge branch line. These unique railway bridges feature a single-cell, continuous steel box girder superstructure supported by pairs of steel delta legs. The top flange of the box girder is an orthotropic deck plate that is a part of the ballast containment trough. Stability of the delta legs is provided by posttensioning of their bases to the concrete substructure. Key words: rail bridge, steel box girder, steel delta legs, orthotropic deck, posttensioning.

scholarly journals Barotropic Regeneration of Upper-Level Synoptic Disturbances in Different Configurations of the Zonal Weather Regime

2008 ◽  
Vol 65 (10) ◽  
pp. 3159-3178 ◽  
Author(s):  
Gwendal Rivière
Keyword(s):  
Large Scale ◽  
Deformation Field ◽  
Regeneration Process ◽  
Barotropic Model ◽  
Weather Regime ◽  
The North ◽  
The Difference ◽  
Upper Level ◽  
Composite Maps ◽  
Large Scale Flow

Barotropic dynamics of upper-tropospheric midlatitude disturbances evolving in different configurations of the zonal weather regime (i.e., in different zonal-like large-scale flows) were studied using observational analyses and barotropic model experiments. The contraction stage of upper-level disturbances that follows their elongation stage leads to an increase of eddy kinetic energy that is called the barotropic regeneration process in this text. This barotropic mechanism is studied through notions of barotropic critical regions (BtCRs) and effective deformation that have been introduced in a previous paper. The effective deformation field is equal to the difference between the square of the large-scale deformation magnitude and the square of the large-scale vorticity. Regions where the effective deformation is positive correspond to regions where the large-scale flow tends to strongly stretch synoptic disturbances. A BtCR is an area separating two large-scale regions of positive effective deformation, one located upstream and on the south side of the jet and the other downstream and on the north side. Such a region presents a discontinuity in the orientation of the dilatation axes and is a potential area where the barotropic regeneration process may occur. Winter days presenting a zonal weather regime in the 40-yr ECMWF Re-Analysis dataset are decomposed, via a partitioning algorithm, into different configurations of the effective deformation field at 300 hPa. A six-cluster partition is obtained. Composite maps of the barotropic generation rate for each cluster exhibit a succession of negative and positive values on both sides of the BtCRs. It confirms statistically that the barotropic regeneration mechanism occurs preferentially about BtCRs. Numerical experiments using a forced barotropic model on the sphere are performed. Each experiment consists of adding a synoptic-scale perturbation to one of the zonal-like jet configurations found in observations, which is kept fixed with time. The combined effects of the effective deformation and nonlinearities are shown to be crucial to reproduce the barotropic regeneration process about BtCRs.

FDA’s reduced exposure marketing order for IQOS: why it is not a reliable global model

2021 ◽  
pp. tobaccocontrol-2020-056316
Author(s):  
Lauren Kass Lempert ◽  
Stella Bialous ◽  
Stanton Glantz
Keyword(s):  
Public Relations ◽  
Tobacco Control ◽  
Scientific Evidence ◽  
Tobacco Product ◽  
Tobacco Products ◽  
Sales And Marketing ◽  
Philip Morris ◽  
The Us ◽  
The Usa ◽  
The Difference

The US Food and Drug Administration (FDA) issued orders in July 2020 authorising Philip Morris Products S.A. to market its heated tobacco product (HTP) IQOS inside the USA with claims that it reduces exposure to some dangerous substances. FDA’s ‘reduced-exposure’ orders explicitly prohibit the marketing of IQOS with claims that IQOS will reduce harm or the risk of tobacco-related diseases. Under US law, FDA’s IQOS orders are problematic because FDA disregarded valid scientific evidence that IQOS increases exposure to other dangerous toxins and that Philip Morris Products S.A. failed to demonstrate that consumers understand the difference between reduced-exposure and reduced-harm claims. Unfortunately, both ‘reduced-exposure’ and ‘reduced-harm’ are classified as ‘modified risk tobacco products’ under US law. Exploiting this confusion, Philip Morris International used the FDA decision as the basis for marketing and public relations campaigns outside the USA to press governments to reverse policies that ban or regulate the sales and marketing of HTPs, including IQOS. Parties to the WHO Framework Convention on Tobacco Control should reject tobacco companies’ unsubstantiated explicit or implied claims of reduced harm associated with HTPs and resist Philip Morris International’s and other companies’ calls to relax HTP regulations based on the FDA’s actions. Instead, parties should adopt policies aligned with the Framework Convention on Tobacco Control when dealing with HTPs and other novel tobacco products.

United Front: Partisans of the Leningrad Region and their connections with the Central Asian Soviet Republics

2021 ◽  
Vol 2021 (02) ◽  
pp. 214-225
Author(s):  
Sergey Kulik ◽  
Аnatoliy Kashevarov ◽  
Zamira Ishankhodjaeva
Keyword(s):  
World War Ii ◽  
Weather Conditions ◽  
Leningrad Region ◽  
World War ◽  
North West ◽  
The North ◽  
Occupied Territory ◽  
Central Asian ◽  
The Difference ◽  
Almost All

During World War II, representatives of almost all the Soviet Republics fought in partisan detachments in the occupied territory of the Leningrad Region. Among them were many representatives of the Central Asian republics: Kazakhstan, Kyrgyzstan and Uzbekistan. Many Leningrad citizens, including relatives of partisans, had been evacuated to Central Asia by that time. However, representatives of Asian workers’ collectives came to meet with the partisans. The huge distance, the difference in cultures and even completely different weather conditions did not become an obstacle to those patriots-Turkestanis who joined the resistance forces in the North-West of Russia.

The Effect of COVID-19 as an Economic Shock on the Gender and Ethnic Gap in Labour Market Outcomes

2021 ◽  
pp. 232102222110464
Author(s):  
Stefani Milovanska-Farrington
Keyword(s):  
Labour Market ◽  
Ethnic Groups ◽  
Global Economy ◽  
Policy Decision ◽  
Jel Classification ◽  
Market Outcomes ◽  
The Usa ◽  
Economic Shock ◽  
Labour Market Outcomes ◽  
The Difference

With more than 29 million confirmed cases of COVID-19 in the USA and 119 million cases worldwide, the pandemic has affected companies, households and the global economy. We explore the effect of the economic shock which resulted from this specific health event on labour market outcomes, and the changes in labour market disparities between ethnic groups and genders. The results provide evidence of an adverse effect of COVID-19 on labour market outcomes of all demographic groups, a widening gap between the employment prospects of minorities and whites, but no change in the earnings gaps between ethnic groups. We also do not find a deterioration of the differentials between genders, except the increase in the difference in the duration of unemployment between women and men with children. The findings have implications related to the priorities of policy decision-makers when implementing policies to combat ethnic and gender gaps in the labour market. JEL Classification: J70, J71, J01, J15, J23

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