Journal articles: 'Rail electrification'

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Allen, John G., and Gregory L. Newmark. "The Life and Death of North American Rail Freight Electrification." Transportation Research Record: Journal of the Transportation Research Board 2672, no. 10 (April 10, 2018): 166–75. http://dx.doi.org/10.1177/0361198118768532.

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Although completely dieselized today aside from certain commuter and intercity passenger routes, U.S. railroads were world leaders in electrification in the early 20th century. The Pennsylvania Railroad and the Milwaukee Road had the most extensive electrifications, but several other railroads electrified largely for freight service. This paper explores the decisions to electrify freight railroads in the U.S., Canada, and Mexico (largely for short tunnels where steam locomotives were not practicable, mountain grades, and busy traffic districts), and why electrifications were discontinued (underpowered installations, aging electric infrastructure, and changes in ownership that made electrification geographically obsolete). Energy shortfalls and price spikes since the 1970s have provoked interest in electrification from freight railroads, but this interest has subsided whenever fuel prices decline. Although it is possible that environmental considerations may lead to electrification in some contexts, as long as fossil fuel prices remain low, electrification is unlikely to play a major role on North American railroads.

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Allen, John G. "Reasons for Commuter Rail Electrification: Early 20th Century and Since 2000." Transportation Research Record: Journal of the Transportation Research Board 2673, no. 7 (April 17, 2019): 227–38. http://dx.doi.org/10.1177/0361198119840621.

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Commuter rail electrification is a complex, capital-intensive matter requiring careful study. Between 1905 and 1931, North American railroads inaugurated electrifications for commuter trains that survive today in New York; Philadelphia, Pennsylvania; Chicago, Illinois; and Montréal, Québec, Canada, as well as for intercity passenger trains between New Haven, Connecticut, and Washington, D.C. A renaissance in electrification is taking hold once more. Since 2000, three new-start electrifications have been placed in service: one for intercity passenger trains (between Boston, Massachusetts, and New Haven, Connecticut), and two others for commuter rail (in Mexico City, Mexico, and Denver, Colorado). Two more are proceeding forward (in Toronto, Ontario, Canada, and San Francisco, California). Despite the great changes caused throughout the railroad industry by the mid-20th century switch from steam to diesel, there is little change in the reasons for commuter railroad electrification in the two eras. Although the justification threshold is higher today than in the early 20th century, it has lowered somewhat as various considerations again converge in favor of electric traction. This is important, because electrification both requires and reinforces heavy ridership, and today’s resurgence of electrification is happening amid a sustained upswing in commuter rail ridership.

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Hobbs, I. "High speed power [rail electrification]." Power Engineer 21, no. 2 (2007): 32. http://dx.doi.org/10.1049/pe:20070204.

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Allen, John G. "Redesigning Main Lines for Commuter Rail Electrification." Transportation Research Record: Journal of the Transportation Research Board 2648, no. 1 (January 2017): 33–41. http://dx.doi.org/10.3141/2648-04.

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After decades of relative inactivity, interest in commuter rail electrification is growing. Long limited to already electrified systems in New York City; Philadelphia, Pennsylvania; Chicago, Illinois; and Montreal, Quebec, Canada, commuter rail electrification is increasingly being recognized as a way to increase speed and train throughput on busier properties. Several commuter railroads are planning or implementing new electrification, which presents challenges as well as opportunities. Installing overhead wires and support structures will make track alignments essentially final for the foreseeable future. Therefore, railroads should make any proposed changes to track layout and elevation before electrification. Other right-of-way considerations are also noted. As interest in commuter rail electrification grows, best practices from early 20th-century projects will be relevant for future installations. Between the 1900s and the 1930s, railroads electrifying their suburban and intercity passenger operations found ways to accommodate different types of trains, meet the needs of peak-period service, and keep different types of trains out of each other’s way, to the maximum extent possible. Alternatives for track arrangements are examined in the context of operating and right-of-way needs of the railroads implementing each configuration.

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Wilson, Roger. "Electrification of US opening rail bridges." Proceedings of the Institution of Civil Engineers - Civil Engineering 156, no. 2 (May 2003): 86–93. http://dx.doi.org/10.1680/cien.2003.156.2.86.

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Glickenstein, Harvey. "Freight Rail Electrification Extended [Transportation Systems]." IEEE Vehicular Technology Magazine 7, no. 3 (September 2012): 18–22. http://dx.doi.org/10.1109/mvt.2012.2203989.

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Streuling, Christoph, Johannes Pagenkopf, Moritz Schenker, and Kim Lakeit. "Techno-Economic Assessment of Battery Electric Trains and Recharging Infrastructure Alternatives Integrating Adjacent Renewable Energy Sources." Sustainability 13, no. 15 (July 23, 2021): 8234. http://dx.doi.org/10.3390/su13158234.

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Battery electric multiple units (BEMU) are an effective path towards a decarbonized regional rail transport on partly electrified rail lines. As a means of sector coupling, the BEMU recharging energy demand provided through overhead line islands can be covered from decentralized renewable energy sources (RES). Thus, fully carbon-free electricity for rail transport purposes can be obtained. In this study, we analyze cost reduction potentials of efficient recharging infrastructure positioning and the feasibility of covering BEMU energy demand by direct-use of locally produced renewable electricity. Therefore, we set up a model-based approach which assesses relevant lifecycle costs (LCC) of different trackside electrification alternatives comparing energy supply from local RES and grid consumption. The model-based approach is applied to the example of a German regional rail line. In the case of an overhead line island, the direct-use of electricity from adjacent wind power plants with on-site battery storage results in relevant LCC of EUR 173.4 M/30a, while grid consumption results in EUR 176.2 M/30a whereas full electrification results in EUR 224.5 M/30a. Depending on site-specific factors such as existing electrification and line lengths, BEMU operation and partial overhead line extension can lead to significant cost reductions of recharging infrastructure as compared to full electrification.

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Mun,Jin-Su and 김덕광. "Evaluation of the Benefits of Rail Electrification." Journal of Transport Research 17, no. 4 (December 2010): 13–25. http://dx.doi.org/10.34143/jtr.2010.17.4.13.

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You, Wei. "The Economics of Speed: The Electrification of the Streetcar System and the Decline of Mom-and-Pop Stores in Boston, 1885–1905." American Economic Journal: Applied Economics 13, no. 4 (October 1, 2021): 285–324. http://dx.doi.org/10.1257/app.20180795.

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Small firms dominated the American economy in the nineteenth century, and they still dominate in many developing economies today. This paper tests whether geographic market segmentation due to underdeveloped intracity transportation technology precludes the emergence of large retail/wholesale stores. I exploit the natural experiment of Boston’s rapid electrification from its previous horse-drawn streetcar system, which occurred between 1889 and 1896. Analyzing newly digitized data, I find that rail-connected locations experienced a sharp decline in the share of sole proprietorships among food retail/wholesale establishments after the electrification relative to off-rail locations. Changes in market access due to streetcar electrification can explain this effect. (JEL L25, L81, L92, N71, N91, R41)

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Walter, Stefan, and Martin Fellendorf. "Long-Term Upgrade Strategy for Light Rail and Regional Rail." Transportation Research Record: Journal of the Transportation Research Board 2534, no. 1 (January 2015): 38–47. http://dx.doi.org/10.3141/2534-06.

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Suburban light rail transit (LRT) and regional rail systems face similar challenges when it comes to upgrade perspectives. A particular planning process is required for upgrade measures apart from conventional alignment modifications. This study investigated the similarities between LRT and regional rail characteristics and developed a robust decision framework that linked demand modeling, timetable construction, and infrastructure design in an integrated approach. The study applied a three-stage planning process for a regional railway system in a midsized Austrian city. A multimodal travel demand model that included demographic changes over the next 2 decades was used. Travel demand was calculated with the current timetable and forecasted changes in regional planning. Within a sensitivity analysis, the impact of alternative timetables on modal shift was checked. A detailed analysis of these results was undertaken to optimize the best-ranked timetable model. Different infrastructure measures such as electrification, double-track sections, road grade crossings, station layout, and alignment changes were identified to match the optimal target timetable with fixed hub-to-hub travel times. Various stakeholders were involved in deciding the political objectives of modal shares, transit headways, and regional rail infrastructure. A well-defined planning process with fixed milestones led to a common agreement on a stepwise upgrade plan for the next 25 years. The proposed method can be applied to regional rail as well as LRT.

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Gorbunov, Mykola, Kateryna Kravchenko, Gintautas Bureika, Juraj Gerlici, Olena Nozhenko, Gediminas Vaičiūnas, Vytautas Bučinskas, and Stasys Steišūnas. "Estimation of sand electrification influence on locomotive wheel / rail adhesion processes." Ekspolatacja i Niezawodnosc - Maintenance and Reliability 21, no. 3 (June 20, 2019): 460–67. http://dx.doi.org/10.17531/ein.2019.3.12.

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Palacin, Roberto. "Hyperloop, the Electrification of Mobility, and the Future of Rail Travel [Viewpoint]." IEEE Electrification Magazine 4, no. 3 (September 2016): 4–51. http://dx.doi.org/10.1109/mele.2016.2584918.

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Antoš, Jan. "Energy saving in rail transport." Acta Polytechnica CTU Proceedings 31 (July 14, 2021): 1–4. http://dx.doi.org/10.14311/app.2021.31.0001.

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Aim of this article is to introduce and present advantages and possibilities of using simulation tools to calculate energy flows of tractive vehicle in all phases of its ride. The focus is on the braking phase, especially on the braking energy recuperation that offers the highest energy saving potential.Energetic simulation was carried out as a part of a current railway reconstruction study, which is a good example of possible energetic calculation use. Energetic calculation in the simulation are performed using so called "exact method" developed at the Faculty of Transportation. The advantage of the method is that it provides a high degree of accuracy. Due to the simulation calculation being performed in real-time, the user can enter the calculation even during the simulation. Crucial part ofevery simulation are quality input data, such as vehicle braking characteristic (including all working points below the envelope line together with the efficiency characteristics of the power train parts (engine, transmission, convertor and others)). Also, sufficiently precise (with a precision of 1 meter) railway track details (detailed geometrical and other information on the current and reconstructed railway track or on the railway track proposal.To present savings during the ride, the railway track section on the track Montreál-Sherbrooke was chosen. On this track, (especially electrification and partial reconstruction of the superstructure) is planned. Reconstruction level will be dependant on the local economical and social conditions. However, in the most optimistic case, total electrification of the track will be undertaken, or lower level of the reconstruction when the vehicles that have very similar characteristics. The railway track section is located between the cities of Montreál and Sherbrooke, that are 160 km apart. To compare the current, and possible future, state, comparison of energy consumption of the vehicle was conducted on the same track with the same geometrical characteristics.We can assume that the overall energy intensity of the ride on the newly reconstructed track (eg. with greater radius of the arches) will be lower than the overall energy intensity of the ride on the track before reconstruction. Current data on energetic consumption are not available, therefore they were obtained by simulation and verified by calculations and considered sufficiently accurate.Presumably, the input simulation parameters required for the simulation will not always be delivered in the sufficient quality or will be partly missing completely. In these cases they will be substituted by various algorithms, that can be machine-processed and that are part of the simulation calculations. One of the crucial algorithms is so called "moment efficiency". Its machine processingis not entirely developed and therefore, this simulation will be conducted without its usage. For financial reasons, simulation calculation was verified only by the theoretical physical calculation method. Based on several partial results, emergent computing tool is functional and sufficiently accurate. The simulation program is supposed to be experimentally verified after its finishing.The outcomes presented in this article are calculated by simulated computation and were not confronted with the real situation in any way. However, relevant calculation algorithms, processes and theoretical background of the simulation were already verified on the older software versions. Therefore, the simulated outcomes are supposed to be at least sufficiently accurate to provide preliminary study for the railway reconstruction. Presented calculations were executed by using author’s simulation software.Part of the methodology was taken from the previous, already verified, versions of the software for vehicle ride simulation.

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Chua, Kein Huat, Dick Sang Hoo, Yun Seng Lim, Mohammad BabrdelBonab, Li Wang, and Pei Yin Wong. "Harmonic Analysis of a Third Rail Systems: A Case Study in Malaysia." Journal of Electronics and Advanced Electrical Engineering 1, no. 2 (May 3, 2021): 26–33. http://dx.doi.org/10.47890/jeaee/2020/keinhuatchua/11120010.

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Harmonic distortion is one of the most important power quality issues in third rail electrification systems. The use of rectifiers and inverters in the third rail system can inject a significant amount of harmonic distortion to the electrical network. This paper aims to investigate the harmonic distortions for a DC urban third rail system at various operating conditions. The electrical network of Mass Rapid Transit Line 2 (MRT 2) Malaysia is modelled using ETAP software. The model had considered the effect of the inter-phase transformer in the 12-pulse rectifier. The current injection method is used to measure harmonic distortion at Point of Common Coupling (PCC) at the 132 kV and 33 kV buses. A normal and degraded operating conditions of power supply are investigated. From the simulation results, it is found that the 11th and 13th order harmonics have exceeded the statutory limit at 33 kV network for the normal operating condition. For the degraded operating condition, only the 11th harmonic order has exceeded the statutory limit. Keywords: Harmonic Distortion; DC Urban Rail; Various Operating Conditions

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Wiles, Peter, Andrew Walker, and David Idle. "The Auckland rail electrification project, New Zealand: accelerated bridge construction in seismic zones." Proceedings of the Institution of Civil Engineers - Civil Engineering 166, no. 5 (May 2013): 50–56. http://dx.doi.org/10.1680/cien.12.00031.

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Rajkumar, P., and B. Vijay Bhaskar. "A Study on Recycling of Saw Dust and Pollution-Free Indian Railways." Shanlax International Journal of Arts, Science and Humanities 8, no. 1 (July 2, 2020): 172–79. http://dx.doi.org/10.34293/sijash.v8i1.3140.

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The Madurai Kamaraj University is situated in Madurai town, Tamil Nadu state, India is an urban area has geographical Location of Latitude 9.941418, Longitude 78.008896 and GPS Latitude coordinates - 9° 56’ 29. 1048 “N and Longitude 78° 0’ 32.0256 “E. The population in Madurai metropolitan town is around 14, 65,625 Lakhs (in 2011 census)-[Male-7, 33,821 Lakhs and female-7, 31,804 Lakhs]. The study of air pollution in this paper consist of two parts- One part deals with (1): The survey of Improved air quality dedicated to nation by Indian Rail Transport (98.5%), in outdoor air pollution control, which is done by a conversion process of electrification implemented in all rail tracks in India - and other part deals with (2): Indoor air pollution generated in a saw mill may be handled by best solid waste recycling process of – compost method for agricultural usage. This study of saw dust recycling is come under the Indoor air quality engineering .The Indoor air pollution is very important because the outdoor air pollution is lower than Indoor air pollution. Also, the outdoor air is a source of supply of air to indoor environment in a house/ Industry. In general, the saw mill generates more amount of saw dust per year. The solid waste of saw dust is disposed by open firing method, creates air pollution in local atmosphere and creates lot of health problems to working people inside and surrounding living people nearby saw mill in an urban area. The saw dust mixed with (cow + goat dung) is completely converted into natural fertilizer for agriculture. This study also focus on The Indian railway introduces electrification in rail track (except Rameshwaram) in several routes and ensure air pollution free zone that is zero percentage carbon emission zone.

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Riego‐Martinez, Jesus, Marcelo Perez‐Alonso, and Oscar Duque‐Perez. "Influence of the rail electrification system topology on the energy consumption of train trajectories." IET Renewable Power Generation 14, no. 18 (December 2020): 3589–98. http://dx.doi.org/10.1049/iet-rpg.2020.0119.

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Abd Rahman, Farah Asyikin, Mohd Zainal Abidin Ab Kadir, Ungku Anisa Ungku Amirulddin, and Miszaina Osman. "Electrical Performance of Polymer-Insulated Rail Brackets of DC Transit Subjected to Lightning Induced Overvoltage." Materials 14, no. 7 (March 29, 2021): 1684. http://dx.doi.org/10.3390/ma14071684.

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The fourth rail transit is an interesting topic to be shared and accessed by the community within that area of expertise. Several ongoing works are currently being conducted especially in the aspects of system technical performances including the rail bracket component and the sensitivity analyses on the various rail designs. Furthermore, the lightning surge study on railway electrification is significant due to the fact that only a handful of publications are available in this regard, especially on the fourth rail transit. For this reason, this paper presents a study on the electrical performance of a fourth rail Direct Current (DC) urban transit affected by an indirect lightning strike. The indirect lightning strike was modelled by means of the Rusck model and the sum of two Heidler functions. The simulations were carried out using the EMTP-RV software which included the performance comparison of polymer-insulated rail brackets, namely the Cast Epoxy (CE), the Cycloaliphatic Epoxy A (CEA), and the Glass Reinforced Plastic (GRP) together with the station arresters when subjected by 30 kA (5/80 µs) and 90 kA (9/200 µs) lightning currents. The results obtained demonstrated that the GRP material has been able to slightly lower its induced overvoltage as compared to other materials, especially for the case of 90 kA (9/200 µs), and thus serves better coordination with the station arresters. This improvement has also reflected on the recorded residual voltage and energy absorption capacity of the arrester, respectively.

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Uzuka, Tetsuo. "Faster than a Speeding Bullet: An Overview of Japanese High-Speed Rail Technology and Electrification." IEEE Electrification Magazine 1, no. 1 (September 2013): 11–20. http://dx.doi.org/10.1109/mele.2013.2271839.

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Bradwell, A., and G. A. Bates. "Analysis of dielectric measurements on switchgear bushings in British Rail 25 kV electrification switching stations." IEE Proceedings B Electric Power Applications 132, no. 1 (1985): 1. http://dx.doi.org/10.1049/ip-b.1985.0001.

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Azadeh, A., V. Salehi, and M. Kianpour. "Performance evaluation of rail transportation systems by considering resilience engineering factors: Tehran railway electrification system." Transportation Letters 10, no. 1 (July 11, 2016): 12–25. http://dx.doi.org/10.1080/19427867.2016.1207928.

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Marin, G. D., G. F. Naterer, and K. Gabriel. "Rail transportation by hydrogen vs. electrification – Case study for Ontario Canada, I: Propulsion and storage." International Journal of Hydrogen Energy 35, no. 12 (June 2010): 6084–96. http://dx.doi.org/10.1016/j.ijhydene.2010.03.098.

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Kirkwood, L., L. Giuntini, E. Shehab, and P. Baguley. "Development of a Whole Life Cycle Cost Model for Electrification options on the UK Rail System." Procedia CIRP 47 (2016): 1–5. http://dx.doi.org/10.1016/j.procir.2016.03.067.

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Marin, G. D., G. F. Naterer, and K. Gabriel. "Rail transportation by hydrogen vs. electrification – Case study for Ontario, Canada, II: Energy supply and distribution." International Journal of Hydrogen Energy 35, no. 12 (June 2010): 6097–107. http://dx.doi.org/10.1016/j.ijhydene.2010.03.095.

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Cha, Yingying, Saeed Abbasi, and Ulf Olofsson. "Indoor and outdoor measurement of airborne particulates on a commuter train running partly in tunnels." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 232, no. 1 (April 7, 2016): 3–13. http://dx.doi.org/10.1177/0954409716642492.

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Wear processes from mechanical braking, rail/wheel contact, the railway electrification system and re-suspended materials due to the turbulence of passing trains in tunnels and stations have been suggested to be the main contributors to particulate matter levels inside trains. In this study, onboard monitoring was performed on a commuter train stopping at underground and aboveground stations. The concentration and size distribution of particulates were monitored for both indoor and outdoor levels. The results show that the levels of PM10 and PM2.5 inside the train were about one-fifth of the outdoor levels. Significant increases in indoor particulate number concentrations were observed in tunnel environments and there was a slight increase when the doors were open. Differences in the size distributions of micro- and nano-sized particulates could be identified for different tunnels.

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Sharma, Rohit. "Financing Indian Urban Rail through Land Development: Case Studies and Implications for the Accelerated Reduction in Oil Associated with 1.5 °C." Urban Planning 3, no. 2 (April 24, 2018): 21–34. http://dx.doi.org/10.17645/up.v3i2.1158.

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Urban travel demand and oil dependence need dramatic change to achieve the 1.5 °C degree target especially with the electrification of all land-based passenger transport and the decarbonizing of electric power. In this article we investigate the transition of ‘oil-based automobile dependence’ to ‘urban rail plus renewable energy’ to cater for transport demand in Indian cities. India is perceived to be a key driver of global oil demand in coming decades due to the potential increase in car use driven by a fast growing national average income. However, it is possible that India could surprise the world by aggressively pursuing an electrified transit agenda within and between cities and associated supporting local transport with electric vehicles, together with renewable power to fuel this transport. The changes will require two innovations that this article focuses on. First, innovative financing of urban and intercity rail through land-based finances as funding and financing of such projects has been a global challenge. Second, enabling Indian cities to rapidly adopt solar energy for all its electrified transport systems over oil plus car dependence. The article suggests that Indian cities may contribute substantially to the 1.5 °C agenda as both policies appear to be working.

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Choi, Z. H., C. L. Toh, and M. H. Z. Hilmi. "Comparative study of two potential recuperating converters in DC railway electrification system for harmonic mitigation." International Journal of Power Electronics and Drive Systems (IJPEDS) 10, no. 3 (September 1, 2019): 1157. http://dx.doi.org/10.11591/ijpeds.v10.i3.pp1157-1166.

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<span>The regenerative braking energy produced by Light-Rail-Transit (LRT) train is commonly transferred back to power grid via a conventional three-phase inverter (recuperating converter). Although this is a cost saving solution but the ac grid current and voltage waveforms were distorted. Hence passive filters are integrated to mitigate the harmonics. This paper proposed to replace the conventional inverter system with a multilevel converter. Cascaded H-Bridge (CHB) converter and Modular Multilevel Converter (MMC) are selected to be evaluated in this paper due to their modularity structures. The aim of this study is to determine the most potential multilevel converter to be implemented without additional passive filters. Nine-level CHB and nine-level MMC converters are modeled with MATLAB/Simulink simulation tool. Both converters are modulated with Level-Shifted Pulse Width Modulation technique. The output voltage and current waveforms generated by CHB and MMC are presented with full analysis. It is concluded that MMC converter is more suitable to be used as a recuperating converter. It produces a clean voltage and current waveforms. The voltage and current Total Harmonic Distortion (THD) indexes are found approximate to 8% and 3%.</span>

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Tang, Yongming, Xiangshen He, and Jiawei Cao. "Fast calculation method of transient temperature rise of motor for electro-mechanical braking." Science Progress 104, no. 2 (April 2021): 003685042110245. http://dx.doi.org/10.1177/00368504211024553.

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Electro-mechanical braking is a new braking mode of rail vehicles, which has the advantages of compact structure, fast response speed, and high precision. It is a new braking technology that conforms to the development trend of full electrification and full intelligence of rail transit brake devices. Due to the special power demand of the electro-mechanical braking device, the electro-mechanical braking motor has a short-time and intermittent working mechanism and is in the state of blocking during working, resulting in its high-temperature rise. Therefore, it is necessary to calculate the temperature rise of the motor quickly and accurately at the beginning of its design. To address this problem, based on the coupling calculation of the equivalent thermal circuit method and the equivalent magnetic circuit method, a fast temperature rise calculation method of the motor is proposed. Then, using the fast calculation method, the temperature rise of the electro-mechanical brake motor under different working periods and wind speed is calculated. By function fitting the calculated results, the motor temperature rise curve fitting function is obtained, which can accurately predict the temperature rise of the motor under different working conditions. It provides a theoretical basis for the use of electro-mechanical braking motor in different working conditions and also provides a reference for the design of the electro-mechanical braking motor.

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Zenith, Federico, Raphael Isaac, Andreas Hoffrichter, Magnus Skinlo Thomassen, and Steffen Møller-Holst. "Techno-economic analysis of freight railway electrification by overhead line, hydrogen and batteries: Case studies in Norway and USA." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 234, no. 7 (August 15, 2019): 791–802. http://dx.doi.org/10.1177/0954409719867495.

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Two non-electrified railway lines, one in Norway and the other in the USA, are analysed for their potential to be electrified with overhead line equipment, batteries, hydrogen or hydrogen-battery hybrid powertrains. The energy requirements are established with single-train simulations, including the altitude profiles of the lines, air and rolling resistances, and locomotive tractive-effort curves. The composition of the freight trains, in terms of the number of locomotives, battery wagons, hydrogen wagons, etc. is also calculated by the same model. The different technologies are compared by the criteria of equivalent annual costs, benefit–cost ratio, payback period and up-front investment, based on the estimated techno-economic parameters for years 2020, 2030 and 2050. The results indicate the potential of batteries and fuel cells to replace diesel on rail lines with low traffic volumes.

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Kirsch, David A., and Gijs P. A. Mom. "Visions of Transportation: The EVC and the Transition from Service- to Product-Based Mobility." Business History Review 76, no. 1 (2002): 75–110. http://dx.doi.org/10.2307/4127752.

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The Electric Vehicle Company (EVC) and its affiliated operating entities (1897–1912), along with similar electric taxicab ventures in London and Paris, figured prominently in the early history of the automobile industry. Long dismissed as a quintessential instance of business failure resulting from the choice of inferior technology, the picture of EVC that emerges from new archival evidence suggests a different view. Seen within the continuing electrification of urban transit, traditional centralized approaches to transportation management, and genuine uncertainty about future automotive technology, EVC constituted a significant, if incremental, extension of traditional, service-based concepts of transportation. The goal of the owners of EVC was to offer an integrated, all-electric urban transportation service that included road- and rail-based components. The failure of EVC represented not simply the victory of internal combustion over electric propulsion but also the triumph of a decentralized, product-centered view of mobility, in which individuals owned and operated their own vehicles.

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Kurtulus and Cetin. "Assessing the Environmental Benefits of Dry Port Usage: A Case of Inland Container Transport in Turkey." Sustainability 11, no. 23 (November 29, 2019): 6793. http://dx.doi.org/10.3390/su11236793.

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Inland transportation of maritime freight conducted by trucks creates extensive emissions. These emissions can be mitigated by using intermodal-rail transport through dry ports. In that regard, this study evaluated the environmental benefits of dry port usage by using discrete event simulation modelling. The results show that the current level of dry port-based intermodal transportation decreases greenhouse gas (GHG) emissions by 5.79% compared to transportation of all containers on the road. Evaluating the impact of the electrified railway line on the GHG emissions revealed unexpected results; the electrification of the railway line would decrease GHG emissions only by 0.06%. The improvements in empty container movement and scheduling slightly reduced GHG emissions by 0.69% and 0.63% respectively, however, highest GHG emissions reduction resulted from modal shift by 6.56%. This study extended the previous literature by assessing not only the environmental benefits of dry port usage but also its effects on train capacity usage, while taking the empty container movement into account.

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Baker, C. J., L. Chapman, A. Quinn, and K. Dobney. "Climate change and the railway industry: A review." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 224, no. 3 (May 22, 2009): 519–28. http://dx.doi.org/10.1243/09544062jmes1558.

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This article considers the issues surrounding climate change and the rail industry in two ways. First, it discusses the role that railways could play in reducing overall greenhouse gas (GHG) emissions and thus help to reduce and mitigate the global temperature increase that will occur over the coming decades. It is argued that, while railways in general have lower emissions than other modes, if a significant decrease in emissions is to be attained, then the capacity of the current rail network needs to be greatly increased to encourage a significant modal shift from road and domestic air travel. Electrification and the provision of high-speed lines can also play a role in this regard, but only if the power that is drawn from the grid is supplied by low carbon sources. Second, the article considers the effect of climate change on the operation of the railway in the next few decades and the adaptations that will be required. The main effects of such changes are likely to be an increase in the track buckling problem, severe strain on railway drainage systems, and the increased likelihood of disruption because of extreme weather events. Ongoing work in this field, aimed at making the railways more resilient, is discussed. It is concluded that, for each of the two areas considered, there is a need for overall system modelling, both to fully evaluate possible mechanisms to reduce GHG emissions, taking account of transfer between modes, capacity limitations, and the national energy mix; and to properly evaluate the major climate change risks to railway operation and to prioritize the use of resources in tackling these issues.

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Pinon Pereira Dias, Joao, and Masafumi Miyatake. "Increase in Robustness against Effects of Coil Misalignment on Electrical Parameters Using Magnetic Material Layer in Planar Coils of Wireless Power Transfer Transformer." Energies 11, no. 8 (July 30, 2018): 1970. http://dx.doi.org/10.3390/en11081970.

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Utilization of wireless power transfer in light rail transits is seen as one solution for electrification of lines. The main advantage of this supply system is the reduction of installation; moreover, the alignment between the transmitter coil in the track and the receiver coil in the train should be perfect in order not to affect the power transfer. To reduce the effects of misalignment on the input and output electric parameters of the system, a new planar core and coil design, called hybrid intercore coil, is proposed. The proposed design uses a magnetic material layer between the windings in the inner half of the coil to create a non-uniform magnetic field distribution, which makes the system more robust against the effects of coil misalignment on the system current and voltage. Simulations with finite element method software were conducted to compare designs. The results show that the proposed design is less susceptible to the effects of misalignment and is more efficient. Prototype cores were constructed to verify the simulation results. Measurements show a smaller input overcurrent and output overvoltage when operating in resonance mode. The proposed design reduced the effects of coil misalignment on electrical parameters.

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Khalili, Siavash, Eetu Rantanen, Dmitrii Bogdanov, and Christian Breyer. "Global Transportation Demand Development with Impacts on the Energy Demand and Greenhouse Gas Emissions in a Climate-Constrained World." Energies 12, no. 20 (October 12, 2019): 3870. http://dx.doi.org/10.3390/en12203870.

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The pivotal target of the Paris Agreement is to keep temperature rise well below 2 °C above the pre-industrial level and pursue efforts to limit temperature rise to 1.5 °C. To meet this target, all energy-consuming sectors, including the transport sector, need to be restructured. The transport sector accounted for 19% of the global final energy demand in 2015, of which the vast majority was supplied by fossil fuels (around 31,080 TWh). Fossil-fuel consumption leads to greenhouse gas emissions, which accounted for about 8260 MtCO2eq from the transport sector in 2015. This paper examines the transportation demand that can be expected and how alternative transportation technologies along with new sustainable energy sources can impact the energy demand and emissions trend in the transport sector until 2050. Battery-electric vehicles and fuel-cell electric vehicles are the two most promising technologies for the future on roads. Electric ships and airplanes for shorter distances and hydrogen-based synthetic fuels for longer distances may appear around 2030 onwards to reduce the emissions from the marine and aviation transport modes. The rail mode will remain the least energy-demanding, compared to other transport modes. An ambitious scenario for achieving zero greenhouse gas emissions by 2050 is applied, also demonstrating the very high relevance of direct and indirect electrification of the transport sector. Fossil-fuel demand can be reduced to zero by 2050; however, the electricity demand is projected to rise from 125 TWhel in 2015 to about 51,610 TWhel in 2050, substantially driven by indirect electricity demand for the production of synthetic fuels. While the transportation demand roughly triples from 2015 to 2050, substantial efficiency gains enable an almost stable final energy demand for the transport sector, as a consequence of broad electrification. The overall well-to-wheel efficiency in the transport sector increases from 26% in 2015 to 39% in 2050, resulting in a respective reduction of overall losses from primary energy to mechanical energy in vehicles. Power-to-fuels needed mainly for marine and aviation transport is not a significant burden for overall transport sector efficiency. The primary energy base of the transport sector switches in the next decades from fossil resources to renewable electricity, driven by higher efficiency and sustainability.

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Kim, Min-Kyeong, Duckshin Park, Minjeong Kim, Jaeseok Heo, Sechan Park, and Hwansoo Chong. "A Study on Characteristic Emission Factors of Exhaust Gas from Diesel Locomotives." International Journal of Environmental Research and Public Health 17, no. 11 (May 27, 2020): 3788. http://dx.doi.org/10.3390/ijerph17113788.

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Use of diesel locomotives in transport is gradually decreasing due to electrification and the introduction of high-speed electric rail. However, in Korea, up to 30% of the transportation of passengers and cargo still uses diesel locomotives and diesel vehicles. Many studies have shown that exhaust gas from diesel locomotives poses a threat to human health. This study examined the characteristics of particulate matter (PM), nitrogen oxides (NOx), carbon monoxide (CO), and hydrocarbons in diesel locomotive engine exhaust. Emission concentrations were evaluated and compared with the existing regulations. In the case of PM and NOx, emission concentrations increased as engine output increased. High concentrations of CO were detected at engine start and acceleration, while hydrocarbons showed weakly increased concentrations regardless of engine power. Based on fuel consumption and engine power, the emission patterns of PM and gaseous substances observed in this study were slightly higher than the U.S. Environmental Protection Agency Tier standard and the Korean emission standard. Continuous monitoring and management of emissions from diesel locomotives are required to comply with emission standards. The findings of this study revealed that emission factors varied based on fuel consumption, engine power, and actual driving patterns. For the first time, a portable emission measurement system (PEMS), normally used to measure exhaust gas from diesel vehicles, was used to measure exhaust gas from diesel locomotives, and the data acquired were compared with previous results. This study is meaningful as the first example of measuring the exhaust gas concentration by connecting a PEMS to a diesel locomotive, and in the future, a study to measure driving characteristics and exhaust gas using a PEMS should be conducted.

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Jackson, Kenneth T. "Review: The Port of New York: A History of the Rail and Terminal System from the Beginnings to Pennsylvania Station by Carl W. Condit; The Port of New York: A History of the Rail and Terminal System from the Grand Central Electrification to the Present by Carl W. Condit." Journal of the Society of Architectural Historians 46, no. 2 (June 1, 1987): 198–99. http://dx.doi.org/10.2307/990199.

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Zapata, Christina B., Chris Yang, Sonia Yeh, Joan Ogden, and Michael J. Kleeman. "Estimating criteria pollutant emissions using the California Regional Multisector Air Quality Emissions (CA-REMARQUE) model v1.0." Geoscientific Model Development 11, no. 4 (April 11, 2018): 1293–320. http://dx.doi.org/10.5194/gmd-11-1293-2018.

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Abstract. The California Regional Multisector Air Quality Emissions (CA-REMARQUE) model is developed to predict changes to criteria pollutant emissions inventories in California in response to sophisticated emissions control programs implemented to achieve deep greenhouse gas (GHG) emissions reductions. Two scenarios for the year 2050 act as the starting point for calculations: a business-as-usual (BAU) scenario and an 80 % GHG reduction (GHG-Step) scenario. Each of these scenarios was developed with an energy economic model to optimize costs across the entire California economy and so they include changes in activity, fuels, and technology across economic sectors. Separate algorithms are developed to estimate emissions of criteria pollutants (or their precursors) that are consistent with the future GHG scenarios for the following economic sectors: (i) on-road, (ii) rail and off-road, (iii) marine and aviation, (iv) residential and commercial, (v) electricity generation, and (vi) biorefineries. Properly accounting for new technologies involving electrification, biofuels, and hydrogen plays a central role in these calculations. Critically, criteria pollutant emissions do not decrease uniformly across all sectors of the economy. Emissions of certain criteria pollutants (or their precursors) increase in some sectors as part of the overall optimization within each of the scenarios. This produces nonuniform changes to criteria pollutant emissions in close proximity to heavily populated regions when viewed at 4 km spatial resolution with implications for exposure to air pollution for those populations. As a further complication, changing fuels and technology also modify the composition of reactive organic gas emissions and the size and composition of particulate matter emissions. This is most notably apparent through a comparison of emissions reductions for different size fractions of primary particulate matter. Primary PM2.5 emissions decrease by 4 % in the GHG-Step scenario vs. the BAU scenario while corresponding primary PM0.1 emissions decrease by 36 %. Ultrafine particles (PM0.1) are an emerging pollutant of concern expected to impact public health in future scenarios. The complexity of this situation illustrates the need for realistic treatment of criteria pollutant emissions inventories linked to GHG emissions policies designed for fully developed countries and states with strict existing environmental regulations.

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Allen, John G., and Herbert S. Levinson. "Former Electrified Commuter Railroads." Transportation Research Record: Journal of the Transportation Research Board 2275, no. 1 (January 2012): 102–10. http://dx.doi.org/10.3141/2275-12.

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During the first third of the 20th century, 16 commuter rail operations in major North American metropolitan areas adopted electric traction. Ten of these electrifications survive. The other six were discontinued between 1929 and 1949, although parts of the alignments of some properties have been returned to regional transit use. With a comparison of the histories of the former electric railroads with those of operations that survived, the reasons for their discontinuance are investigated. Perhaps unexpectedly, the Great Depression does not solely account for the demise of most of these lines. Instead, major geographic barriers precluding direct downtown service and the construction of new highway links appear to have been at least as important. Furthermore, all surviving electrifications addressed practical operating needs. However, no installations undertaken as technological test beds or in response to competing lines have survived.

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Liu, Weisheng, and Boqiang Lin. "Electrification of rails in China: Its impact on energy conservation and emission reduction." Energy 226 (July 2021): 120363. http://dx.doi.org/10.1016/j.energy.2021.120363.

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Pereira, Rebeca Fonseca de Oliveira, and Rachel Albrecht. "EVOLUÇÃO TEMPORAL DA PRECIPITAÇÃO E ATIVIDADE ELÉTRICA DE UMA TEMPESTADE COM OCORRÊNCIA DE TEMPO SEVERO." Ciência e Natura 38 (July 20, 2016): 532. http://dx.doi.org/10.5902/2179460x20291.

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This study aimed to analyze the spatial and temporal evolution of rainfall and electrification of a Convective System, which occured on March 12, 2012 over the city of São Paulo, during the time interval from 1830 to 1945 UTC. An analysis was made of the behavior of the three dimensional structure of radar reflectivity and lightning type Intra-cloud (IN) and Cloud-Solo (NS), based on two lightning detection networks installed in the region during the RAIN Project, in order to correlate the occurrence of severe weather to the evolution of cloud ascending current, precipitation formation and electrification of this storm. It was observed by the reflectivity of the FCTH Radar images that, at times, the SC showed high values of reflectivity, with over 70 dBZ and indicating the presence of hail within the system. Through the behavior of electrical discharges, it is also noted that these accompany the displacement and intensity of the updraft and through the lightning jump, it is possible to detect in advance whether if the storm is intensifying or not. If so, this storm could possibly become a severe weather and cause serious damage to society.

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Fierro, Alexandre O., Edward R. Mansell, Conrad L. Ziegler, and Donald R. MacGorman. "Explicitly Simulated Electrification and Lightning within a Tropical Cyclone Based on the Environment of Hurricane Isaac (2012)." Journal of the Atmospheric Sciences 72, no. 11 (November 1, 2015): 4167–93. http://dx.doi.org/10.1175/jas-d-14-0374.1.

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Abstract This work analyzes a high-resolution 350-m simulation of the electrification processes within a hurricane in conjunction with available total lightning observations to augment the general understanding of some of the key cloud-scale electrification processes within these systems. The general environment and trends of Hurricane Isaac (2012), whose lightning activity was observed by the Earth Networks Total Lightning Network, were utilized to produce a reasonable tropical cyclone simulation. The numerical model in this work employs explicit electrification and lightning parameterizations within the Weather Research and Forecasting Model. Overall, simulated storm-total flash origin density rates remain comparable to the observations. Because simulated reflectivities were larger and echo tops were higher in the eyewall than observed, the model consistently overestimated lightning rates there. The gross vertical charge structure in the eyewall resembled a normal tripole or a positive dipole, depending on the location. The negative charge at middle levels and positive at upper levels arose primarily from noninductive charging between graupel and ice crystals/snow. As some graupel melted into rain, the main midlevel negative charge region extended down to the surface in some places. The large volume of positively charged snow aloft caused a radially extensive negative screening layer to form on the lighter ice crystals above it. Akin to continental storms and tropical convection, lightning activity in the eyewall was well correlated with the ice water path (r > 0.7) followed by the graupel + hail path (r ≈ 0.7) and composite reflectivity at temperatures less than −10°C and the snow + ice path (r ≈ 0.5). Relative maxima in updraft volume, graupel volume, and total lightning rates in the eyewall all were coincident with the end of an intensification phase.

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Gorgucci, Eugenio, V. Chandrasekar, and Gianfranco Scarchilli. "Radar and Surface Measurement of Rainfall during CaPE: 26 July 1991 Case Study." Journal of Applied Meteorology 34, no. 7 (July 1, 1995): 1570–77. http://dx.doi.org/10.1175/1520-0450-34.7.1570.

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Abstract Conventional usage of multiparameter radar measurements for rainfall estimation has been associated with tracking the variability of the raindrop size distribution. The use of multiparameter radar measurements in a statistical framework to estimate rainfall is presented in this paper. The techniques developed in this paper are applied to the radar and rain gauge measurement of rainfall observed on 26 July 1991, during the Convection and Precipitation Electrification program. Conventional pointwise estimates of rainfall are also compared. The probability matching procedure, when applied to the radar and surface measurements shows that multiparameter radar algorithms can match the probability distribution functions better than the reflectivity based algorithms, thereby indicating the potential of multiparameter radar measurements for statistical approach to rainfall estimation.

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Mansell, Edward R., Conrad L. Ziegler, and Eric C. Bruning. "Simulated Electrification of a Small Thunderstorm with Two-Moment Bulk Microphysics." Journal of the Atmospheric Sciences 67, no. 1 (January 1, 2010): 171–94. http://dx.doi.org/10.1175/2009jas2965.1.

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Abstract Electrification and lightning are simulated for a small continental multicell storm. The results are consistent with observations and thus provide additional understanding of the charging processes and evolution of this storm. The first six observed lightning flashes were all negative cloud-to-ground (CG) flashes, after which intracloud (IC) flashes also occurred between middle and upper levels of the storm. The model simulation reproduces the basic evolution of lightning from low and middle levels to upper levels. The observed lightning indicated an initial charge structure of at least an inverted dipole (negative charge above positive). The simulations show that noninductive charge separation higher in the storm can enhance the main negative charge sufficiently to produce negative CG flashes before upper-level IC flashes commence. The result is a “bottom-heavy” tripole charge structure with midlevel negative charge and a lower positive charge region that is more significant than the upper positive region, in contrast to the traditional tripole structure that has a less significant lower positive charge region. Additionally, the occurrence of cloud-to-ground lightning is not necessarily a result of excess net charge carried by the storm, but it is primarily caused by the local potential imbalance between the lowest charge regions. The two-moment microphysics scheme used for this study predicted mass mixing ratio and number concentration of cloud droplets, rain, ice crystals, snow, and graupel. Bulk particle density of graupel was also predicted, which allows a single category to represent a greater range of particle characteristics. (An additional hail category is available but was not needed for the present study.) The prediction of hydrometeor number concentration is particularly critical for charge separation at higher temperatures (−5° < T < −20°C) in the mixed phase region, where ice crystals are produced by rime fracturing (Hallett–Mossop process) and by splintering of freezing drops. Cloud droplet concentration prediction also affected the rates of inductive charge separation between graupel and droplets.

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Laporte, Stéphane, Gérard Coquery, Virginie Deniau, Alexandre De Bernardinis, and Nicolas Hautière. "Dynamic Wireless Power Transfer Charging Infrastructure for Future EVs: From Experimental Track to Real Circulated Roads Demonstrations." World Electric Vehicle Journal 10, no. 4 (November 24, 2019): 84. http://dx.doi.org/10.3390/wevj10040084.

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In a context of growing electrification of road transport, Wireless Power Transfer (WPT) appears as an appealing alternative technology as it enables Electric Vehicles (EVs) to charge while driving and without any mechanical contact (with overhead cables or rails in the ground). Although the WPT technology background dates from the end of 20th century, recent advances in semiconductor technologies have enabled the first real demonstrations. Within the FABRIC European project, the French research Institute VEDECOM and its partners implemented a whole prototype wireless power transfer charging infrastructure. The first demonstrations of Inductive WPT in different real driving conditions (up to 20 kW, from 0 to 100 km/h, with one or two serial vehicles) were provided. This paper describes the prototype equipment and its instrumentation and provides the system characterization results. The future of the Inductive WPT technology is further discussed considering its different technical and economic challenges. In parallel, how this technology could be part of future generation road infrastructures is discussed. Future research and demonstration steps are presented in the conclusion.

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Mansell, Edward R., and Conrad L. Ziegler. "Aerosol Effects on Simulated Storm Electrification and Precipitation in a Two-Moment Bulk Microphysics Model." Journal of the Atmospheric Sciences 70, no. 7 (July 1, 2013): 2032–50. http://dx.doi.org/10.1175/jas-d-12-0264.1.

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Abstract The effects of cloud condensation nuclei (CCN) concentrations are found to strongly affect the microphysical and electrical evolution of a numerically simulated small multicell storm. The simulations reproduce the well-known effects of updraft invigoration and delay of precipitation formation as increasing CCN from low to intermediate concentrations causes droplet sizes to decrease. Peak updrafts increased from 16 m s−1 at the lowest CCN to a maximum of 21–22 m s−1 at moderate CCN, where condensation latent heating is maximized. The transition from low to high CCN first maximizes warm-rain production before switching over to the ice process as the dominant precipitation mechanism. Average graupel density stays fairly high and constant at lower CCN, but then drops monotonically at higher CCN concentration, although high CCN also foster the appearance of small regions of larger, high-density graupel with high simulated radar reflectivity. Graupel production increases monotonically as CCN concentration rises from 50 to about 2000 cm−3. The lightning response is relatively weak until the Hallett–Mossop rime-splintering ice multiplication becomes more active at CCN > 700 cm−3. At very high CCN concentrations (>2000 cm−3), graupel production decreases slowly, but lightning activity drops dramatically when the parameterization of Hallett–Mossop rime-splintering ice multiplication is based on the number of large cloud droplets collected by graupel. Conversely, lightning activity remains steady at extremely high CCN concentration when the Hallett–Mossop parameterization is based simply on the rate of rime mass accumulation. The results lend support to the aerosol hypothesis as applied to lightning production, whereby greater CCN concentration tends to lead to greater lightning activity, but with a large sensitivity to ice multiplication.

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Hu, Jiaxi, Daniel Rosenfeld, Alexander Ryzhkov, and Pengfei Zhang. "Synergetic Use of the WSR-88D Radars, GOES-R Satellites, and Lightning Networks to Study Microphysical Characteristics of Hurricanes." Journal of Applied Meteorology and Climatology 59, no. 6 (June 2020): 1051–68. http://dx.doi.org/10.1175/jamc-d-19-0122.1.

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AbstractThis study analyzes the microphysics and precipitation pattern of Hurricanes Harvey (2017) and Florence (2018) in both the eyewall and outer rainband regions. From the retrievals by a satellite red–green–blue scheme, the outer rainbands show a strong convective structure while the inner eyewall has less convective vigor (i.e., weaker upper-level reflectivities and electrification), which may be related to stronger vertical wind shear that hinders fast vertical motions. The WSR-88D column-vertical profiles further confirm that the outer rainband clouds have strong vertical motion and large ice-phase hydrometeor formation aloft, which correlates well with 3D Lightning Mapping Array source counts in height and time. From the results from this study, it is determined that the inner eyewall region is dominated by warm rain, whereas the external rainband region contains intense mixed-phase precipitation. External rainbands are defined here as those that reside outside of the main hurricane circulation, associated with surface tropical storm wind speeds. The synergy of satellite and radar dual-polarization parameters is instrumental in distinguishing between the key microphysical features of intense convective rainbands and the warm-rain-dominated eyewall regions within the hurricanes. Substantial amounts of ice aloft and intense updrafts in the external rainbands are indicative of heavy surface precipitation, which can have important implications for severe weather warnings and quantitative precipitation forecasts. The novel part of this study is to combine ground-based radar measurement with satellite observations to study hurricane microphysical structure from surface to cloud top so as to fill in the gaps between the two observational techniques.

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Fierro, Alexandre O., and Edward R. Mansell. "Electrification and Lightning in Idealized Simulations of a Hurricane-Like Vortex Subject to Wind Shear and Sea Surface Temperature Cooling." Journal of the Atmospheric Sciences 74, no. 6 (June 1, 2017): 2023–41. http://dx.doi.org/10.1175/jas-d-16-0270.1.

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Abstract Relationships between intensity fluctuations, cloud microphysics, lightning variations, and electrical structures within idealized tropical cyclones are investigated with the cloud-resolving Collaborative Model for Multiscale Atmospheric Simulation (COMMAS). An initial strong tropical cyclone is subjected to either steady-state control conditions (CTRL), increased wind shear (SHEAR), or a reduction in sea surface temperature (SST). In CTRL, nearly all the lightning (>95%) occurred in the outer region (100 < r ≤ 300 km) and was overall very episodic in the inner core (r ≤ 100 km), consistent with observations. The inner-core updrafts were weaker and experienced greater depletion of cloud water by warm rain processes, which, in contrast to the deeper updrafts in the rainband convection, reduced the mixed-phase cloud depth and confined the bulk of the charging and lightning initiations to lower levels. Notably, larger flash rates were produced in the asymmetric inner core of the SHEAR case, with the majority of the flashes located in the downshear left quadrant, consistent with prior observational works. In contrast to CTRL, the more vigorous inner-core convection in SHEAR resulted in the formation of a prominent negative charge region and enhanced production of negative ground flashes. With a nearly identical filling rate as SHEAR, the introduction of cooler sea surface temperature in the SST case caused lightning activity to fade rapidly in both the inner core and rainbands.

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Defer, E., J. P. Pinty, S. Coquillat, J. M. Martin, S. Prieur, S. Soula, E. Richard, et al. "An overview of the lightning and atmospheric electricity observations collected in southern France during the HYdrological cycle in Mediterranean EXperiment (HyMeX), Special Observation Period 1." Atmospheric Measurement Techniques 8, no. 2 (February 9, 2015): 649–69. http://dx.doi.org/10.5194/amt-8-649-2015.

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Abstract. The PEACH project (Projet en Electricité Atmosphérique pour la Campagne HyMeX – the Atmospheric Electricity Project of the HyMeX Program) is the atmospheric electricity component of the Hydrology cycle in the Mediterranean Experiment (HyMeX) experiment and is dedicated to the observation of both lightning activity and electrical state of continental and maritime thunderstorms in the area of the Mediterranean Sea. During the HyMeX SOP1 (Special Observation Period) from 5 September to 6 November 2012, four European operational lightning locating systems (ATDnet, EUCLID, LINET, ZEUS) and the HyMeX lightning mapping array network (HyLMA) were used to locate and characterize the lightning activity over the northwestern Mediterranean at flash, storm and regional scales. Additional research instruments like slow antennas, video cameras, microbarometer and microphone arrays were also operated. All these observations in conjunction with operational/research ground-based and airborne radars, rain gauges and in situ microphysical records are aimed at characterizing and understanding electrically active and highly precipitating events over southeastern France that often lead to severe flash floods. Simulations performed with cloud resolving models like Meso-NH and Weather Research and Forecasting are used to interpret the results and to investigate further the links between dynamics, microphysics, electrification and lightning occurrence. Herein we present an overview of the PEACH project and its different instruments. Examples are discussed to illustrate the comprehensive and unique lightning data set, from radio frequency to acoustics, collected during the SOP1 for lightning phenomenology understanding, instrumentation validation, storm characterization and modeling.

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Rosenfeld, D., M. Fromm, J. Trentmann, G. Luderer, M. O. Andreae, and R. Servranckx. "The Chisholm firestorm: observed microstructure, precipitation and lightning activity of a pyro-cumulonimbus." Atmospheric Chemistry and Physics 7, no. 3 (February 9, 2007): 645–59. http://dx.doi.org/10.5194/acp-7-645-2007.

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Abstract. A fire storm that occurred on 28 May 2001 and devastated the town of Chisholm, ~150 km north of Edmonton, Alberta, induced a violent fire-invigorated cumulonimbus cloud. This pyro-cumulonimbus (pyro-Cb) had overshooting tops of 2.5–3 km above the tropopause, and injected massive amounts of smoke into the lower stratosphere. Fortunately, this event occurred under good coverage of radar, rain gauge, lightning and satellite measurements, which allowed in-depth documentation of the event, and gave us an opportunity to study the cloud top morphology and microstructure, precipitation and cloud electrification of the pyro-Cb. The combination of heat and smoke created a cloud with extremely small drops, which ascended rapidly in violent updrafts. There appeared to be little freezing up to the homogeneous freezing isotherm level of −38°C. A cloud with such small and short-lived highly supercooled drops is incapable of producing precipitation except for few large graupel and hail, which produced the observed radar echoes and charged the cloud with positive lightning. The small cloud drops froze homogeneously to equally small ice particles, for which there is no mechanism to aggregate into precipitation particles, and which hence remain in the anvil. The lack of significant precipitation implies that only a small fraction of the smoke is scavenged, so that most of it is exhausted through the anvil to the upper troposphere and lower stratosphere. Comparisons with other cases suggest that a pyro-Cb does not have to be as violent as the Chisholm case for precipitation to be strongly suppressed. However, this level of convective vigor is necessary to create the overshooting updraft that injects the smoke into the lower stratosphere.

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Sarmad, Khwaja. "B. M. Bhatia. Indian Agriculture: A Policy Perspective. New'Delhi: Sage Publications India Pvt. Ud., 1988.191 pp.Rupees (Indian) 140.00 (Hardbound Edition)." Pakistan Development Review 28, no. 2 (June 1, 1989): 164–67. http://dx.doi.org/10.30541/v28i2pp.164-167.

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India is self-sufficient in the production of foodgrains, and in good years has substantial exportable surpluses. This is no small achievement for a country which, in the late Sixties, had to import as much as 13 percent of its requirements of foodgrains. The turnaround came as a result of the distribution of high-yielding seeds, fertilizer, modern agricultural technology, and provision of extension services. But agricultural growth has remained concentrated in the north-west of the country, which is well-endowed with infrastructures like irrigation, rural electrification, roads, markets, etc. By one estimate, these areas, which account for less than 15 percent of the total area under foodgrains cultivation in the country, have contributed as much as 56 percent of the increase in foodgrain production in the post-green· revolution period. No doubt, this has led to an increase in the regional disparities as well. Another serious imbalance in Indian agriculture has arisen because of cropwise disparities in growth, between foodgrains and non-foodgrains on the one hand, and among different foodgrains on the other. About 70 percent of the total cultivated area in the country is rain-fed, which contributes a large proportion of the total output of important crops like cereals, pulses, oilseeds, and cotton; and over 40 percent of the total food grains production of the country. But productivity in these areas is low and fluctuates according to the amount of rainfall. Dr Bhatia shows that stagnation in the agriculture sector has coincided not only with adverse weather conditions but also with adverse inputoutput price ratios, particularly between fertilizer and procurement prices of cereals.

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Journal articles on the topic 'Rail electrification'

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