scholarly journals Recent studies on railway-track substructure at TTCI

2020 ◽  
Author(s):  
Dingqing Li ◽  
Stephen Wilk
Keyword(s):  
Cost Effective ◽  
Large Degree ◽  
Railway Track ◽  
Critical Element ◽  
Heavy Haul ◽  
Track Substructure ◽  
And Performance ◽  
Mud Pumping ◽  
Ground Penetrating ◽  
Good Drainage

Abstract Railway-track substructure is the foundation of the railway-track infrastructure and consists of four major components: ballast, sub-ballast, subgrade and drainage. Safety and performance of the track infrastructure, to a large degree, depends on the performance of the track substructure. Adequate support from the track substructure is the most critical element needed for good track performance. When properly constructed and maintained, the ballasted track is the most cost-effective track structure for railway operations, especially for heavy-haul freight operations. Good track-substructure support is characterized by good drainage and strong resistance of the ballast, sub-ballast and subgrade layers to excessive deformation and failures under repeated dynamic wheel loads. As the track substructure plays such important roles, research concerning track substructure has been broad and extensive around the world, with many universities and research institutes conducting various studies and investigations. This paper provides an overview of the recent research conducted at Transportation Technology Center, Inc. (TTCI), a subsidiary of the Association of American Railroads (AAR), in the following areas: ballast mud pumping and its effects on track performance, remediation of subgrade mud pumping, remediation of ballast pockets, ground-penetrating radar (GPR) for inspecting track substructure, and development of software tools with focus on track-substructure functions and management.

China will see off challengers in EV batteries

2021 ◽  
Keyword(s):  
Cost Effective ◽  
Government Support ◽  
Critical Element ◽  
Content Type ◽  
Car Industry ◽  
Mitigate Climate Change ◽  
And Performance ◽  
Critical Mineral ◽  
Wealth Generation ◽  
Global Transition

Significance The battery is the most expensive and performance-critical element of an electric vehicle (EV). China's dominance in the sector therefore has strategic implications, because the global transition towards EVs is key to achieving international targets to mitigate climate change, and to individual nations’ wealth generation prospects. Impacts The car industry worldwide will increasingly depend on access to cost-effective batteries, which in the short term means Chinese suppliers. China’s dominance of the battery supply chain and fast-growing EV market ties foreign automotive leaders to Chinese partners and markets. Extensive government support would be needed to compete with Chinese firms’ dominance in the battery and critical mineral supply chains.

scholarly journals Recent Advances in Conventional Methods and Electrochemical Aptasensors for Mycotoxin Detection

Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1437
Author(s):  
Jing Yi Ong ◽  
Andrew Pike ◽  
Ling Ling Tan
Keyword(s):  
Quantitative Analysis ◽  
Animal Feed ◽  
Cost Effective ◽  
Preventive Action ◽  
High Affinity ◽  
Recent Advances ◽  
Recognition Elements ◽  
Key Features ◽  
Pre Treatment ◽  
And Performance

The presence of mycotoxins in foodstuffs and feedstuffs is a serious concern for human health. The detection of mycotoxins is therefore necessary as a preventive action to avoid the harmful contamination of foodstuffs and animal feed. In comparison with the considerable expense of treating contaminated foodstuffs, early detection is a cost-effective way to ensure food safety. The high affinity of bio-recognition molecules to mycotoxins has led to the development of affinity columns for sample pre-treatment and the development of biosensors for the quantitative analysis of mycotoxins. Aptamers are a very attractive class of biological receptors that are currently in great demand for the development of new biosensors. In this review, the improvement in the materials and methodology, and the working principles and performance of both conventional and recently developed methods are discussed. The key features and applications of the fundamental recognition elements, such as antibodies and aptamers are addressed. Recent advances in aptasensors that are based on different electrochemical (EC) transducers are reviewed in detail, especially from the perspective of the diagnostic mechanism; in addition, a brief introduction of some commercially available mycotoxin detection kits is provided.

scholarly journals Using Aerial and Vehicular NFV Infrastructures to Agilely Create Vertical Services

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1342
Author(s):  
Borja Nogales ◽  
Miguel Silva ◽  
Ivan Vidal ◽  
Miguel Luís ◽  
Francisco Valera ◽  
...  
Keyword(s):  
Ad Hoc Network ◽  
Ad Hoc ◽  
Cost Effective ◽  
Network Services ◽  
Network Function Virtualization ◽  
Mobile Environments ◽  
Network Resources ◽  
The Public ◽  
Network Function ◽  
And Performance

5G communications have become an enabler for the creation of new and more complex networking scenarios, bringing together different vertical ecosystems. Such behavior has been fostered by the network function virtualization (NFV) concept, where the orchestration and virtualization capabilities allow the possibility of dynamically supplying network resources according to its needs. Nevertheless, the integration and performance of heterogeneous network environments, each one supported by a different provider, and with specific characteristics and requirements, in a single NFV framework is not straightforward. In this work we propose an NFV-based framework capable of supporting the flexible, cost-effective deployment of vertical services, through the integration of two distinguished mobile environments and their networks: small sized unmanned aerial vehicles (SUAVs), supporting a flying ad hoc network (FANET) and vehicles, promoting a vehicular ad hoc network (VANET). In this context, a use case involving the public safety vertical will be used as an illustrative example to showcase the potential of this framework. This work also includes the technical implementation details of the framework proposed, allowing to analyse and discuss the delays on the network services deployment process. The results show that the deployment times can be significantly reduced through a distributed VNF configuration function based on the publish–subscribe model.

Nondestructive Test on Typical Roadway Supports of a Mine via Drilling Core and Ground Penetrating Radar

2011 ◽  
Vol 368-373 ◽  
pp. 2411-2416
Author(s):  
Jian Ping Han ◽  
Hai Peng Liu
Keyword(s):  
Ground Penetrating Radar ◽  
Geological Structure ◽  
Surrounding Rock ◽  
Potential Threat ◽  
Real Performance ◽  
Design Requirements ◽  
And Performance ◽  
The Stability ◽  
Ground Penetrating ◽  
Drilling Core

Temporary or permanent supports are necessary in underground construction for maintaining the stability and limiting the damage of surrounding rock. Due to the uncertainty of geological structure, the specificity of the underground environment as well as other factors, the quality and performance of supporting structure are often difficult to satisfy the design requirements, which not only seriously affects the normal construction and operation of mines but also has the potential threat to the safety of underground production. In order to investigate the influence of the unfavorable geologic environment on supporting concrete and evaluate the real performance of roadway supports of a mine, 17 typical projects were chosen and the strength of supporting concrete was detected by nondestructive drilling core method. The result shows that the strength is widely less than the design value. Furthermore, 4 projects of them were investigated by the ground penetrating radar (GPR) in order to evaluate the feasibility of GPR in the performance investigation of the roadway supports of a mine. The results indicate that ground penetrating radar is capable of measuring the thickness of the support, the distribution of rebars and the defects of the surrounding rock.

scholarly journals WHEEL–RAIL WEAR INVESTIGATION ON A HEAVY HAUL BALLOON LOOP TRACK THROUGH SIMULATIONS OF SLOW SPEED WAGON DYNAMICS

Transport ◽  
2018 ◽  
Vol 33 (3) ◽  
pp. 843-852 ◽  
Author(s):  
Yan Quan SUN ◽  
Maksym SPIRYAGIN ◽  
Colin COLE ◽  
Dwayne NIELSEN
Keyword(s):  
Dynamic Behaviour ◽  
Railway Track ◽  
Contact Friction ◽  
Slow Speed ◽  
Wear Process ◽  
Contact Wear ◽  
Rail Wear ◽  
Heavy Haul ◽  
Curve Radius ◽  
Heavy Haul Railway

Heavy haul railway track infrastructure are commonly equipped with balloon loops to allow trains to be loaded/unloaded and/or to reverse the direction of travel. The slow operational speed of trains on these sharp curves results in some unique issues regarding the wear process between wheels and rails. A wagon dynamic system model has been applied to simulate the dynamic behaviour in order to study the wheel–rail contact wear conditions. A wheel–rail wear index is used to assess the wear severity. The simulation shows that the lubrication to reduce the wheel–rail contact friction coefficient can significantly reduce the wear severity. Furthermore, the effects of important parameters on wheel–rail contact wear including curve radius, wagon speed and track superelevation have also been considered.

Solar Photovoltaic Water Pumping to Alleviate Drought in Remote Locations

2006 ◽  
Author(s):  
Kala Meah ◽  
Steven Fletcher ◽  
Yu Wan ◽  
Sadrul Ula
Keyword(s):  
Performance Monitoring ◽  
Cost Effective ◽  
Small Scale ◽  
Solar Water ◽  
Small Water ◽  
Water Pumping ◽  
Western Us ◽  
Water Right ◽  
And Performance ◽  
The University

Many parts of the western US is rural in nature and consequently do not have electrical distribution lines in many parts of farms and ranches. Distribution line extension costs can run from $15,000 to $25,000 per mile, thereby making availability of electricity to small water pumping projects economically unattractive. Solar photo-voltaic (PV) powered water pumping is more cost effective in these small scale applications. Many western states including Wyoming are passing through fifth year of drought with the consequent shortages of water for many applications. Wyoming State Climatologist is predicting a possible 5–10 years of drought. Drought impacts the surface water right away, while it takes much longer to impact the underground aquifers. To mitigate the effect on the livestock and wildlife, Wyoming Governor Dave Freudenthal initiated a solar water pumping initiative in cooperation with the University of Wyoming, County Conservation Districts, Rural Electric Cooperatives, and ranching organizations. Solar water pumping has several advantages over traditional systems; for example, diesel or propane engines require not only expensive fuels, they also create noise and air pollution in many remote pristine areas. Solar systems are environment friendly, low maintenance and have no fuel cost. In this paper the design, installation and performance monitoring of the solar system for small scale remote water pumping will be presented.

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