‘Connecting the unconnected’: a critical assessment of US satellite Internet services

2019 ◽  
Vol 42 (2) ◽  
pp. 260-276 ◽  
Author(s):  
Matthew Graydon ◽  
Lisa Parks
Keyword(s):  
High Speed ◽  
Small Mass ◽  
Production Costs ◽  
Internet Technology ◽  
Internet Services ◽  
Internet Industry ◽  
Industry Research ◽  
History Of ◽  
Synchronous Orbit ◽  
Time And Energy

An estimated 4 billion people worldwide still lack reliable access to the Internet, with the majority concentrated in developing countries. It is within this context that a significant expansion of the satellite Internet industry is taking place, bringing grand visions of social and economic growth through connectivity. Previously dismissed as a limited technology due to high operating costs and latency, as well as the failure of early ventures like Teledesic, satellite Internet has re-emerged in recent years as a viable alternative to the time and energy-intensive practice of laying thousands of miles of fiber optic cable. Utilizing innovative non-synchronous orbit constellations of small, mass-produced satellites that lower production costs and improve latency to better compete with broadband, new Silicon Valley–related companies such as OneWeb, SpaceX, and O3b have promised cheap, high-speed Internet access throughout the world. Drawing upon industry research, site visits, and interviews with technical specialists, development experts, and other actors, this article briefly explores the history of satellite Internet services, analyzes the promises of emerging satellite Internet companies, and argues that without serious commitments from governments and the private sector to follow through on this rhetoric, satellite Internet technology could fail to reach the communities that need it most.

Multiple phase transitions investigated by high-speed TEM

1990 ◽  
Vol 48 (4) ◽  
pp. 550-551
Author(s):  
Oleg Bostanjoglo ◽  
Peter Thomsen-Schmidt
Keyword(s):  
Phase Transitions ◽  
High Speed ◽  
Short Exposure ◽  
Semiconductor Film ◽  
Time Resolved ◽  
Short Exposure Time ◽  
Multiple Phase ◽  
Model Substance ◽  
History Of ◽  
Electron Image

Thin GexTe1-x (x = 0.15-0.8) were studied as a model substance of a composite semiconductor film, in addition being of interest for optical storage material. Two complementary modes of time-resolved TEM were used to trace the phase transitions, induced by an attached Q-switched (50 ns FWHM) and frequency doubled (532 nm) Nd:YAG laser. The laser radiation was focused onto the specimen within the TEM to a 20 μm spot (FWHM). Discrete intermediate states were visualized by short-exposure time doubleframe imaging /1,2/. The full history of a transformation was gained by tracking the electron image intensity with photomultiplier and storage oscilloscopes (space/time resolution 100 nm/3 ns) /3/. In order to avoid radiation damage by the probing electron beam to detector and specimen, the beam is pulsed in this continuous mode of time-resolved TEM,too.Short events ( <2 μs) are followed by illuminating with an extended single electron pulse (fig. 1c)

THE 35TH ANNIVERSARY OF PRODUCTION OF THE DT-175S "VOL-GAR" TRACTOR

2021 ◽  
Vol 1 (142) ◽  
pp. 163-177
Author(s):  
Vyacheslav V. Kosenko ◽  
◽  
Vladimir V. Sharov ◽  
Yuliya S. Tsench ◽  
◽  
...  
Keyword(s):  
High Speed ◽  
Research Purpose ◽  
Mechanical Transmission ◽  
Machine Operators ◽  
History Of ◽  
Close Cooperation ◽  
The Creation ◽  
Agricultural Tractors ◽  
Tractor Driver ◽  
Tractor Plant

The article, dedicated to the 35th anniversary of the start of production at the Volgograd Tractor Plant of the tracked agricultural tractor DT-175S "Volgar", tells about the history of the creation of this unique machine in its own way. (Research purpose) The research purpose is in analyzing the history of the creation and production, the effectiveness of the use of the DT- 175S "Volgar" tractor, considering the stages and directions of its improvement. (Materials and methods) The article de-scribes the history of the creation of the high-speed energy-saturated tractor "Volgar", gave its design features, technical characteristics in comparison with its predecessors, the results of tests in various soil and climatic zones, on various agricultural operations. (Results and discussion) In the DT-175S "Volgar" tractor, the designers, in close cooperation with scientists, embodied the results of research aimed at increasing the working speeds of machine-tractor units, and the most advanced technical solu-tions in the field of tractor construction at that time. The main of these solutions is an automatic continuously variable hydro-mechanical transmission. The combination of a powerful (125 kilowatt) engine with a similar transmission allowed not only signifi-cantly increase the working speed and productivity of the tractor, up to 9-15 kilometers per hour, but also significantly reduce the labor intensity of the tractor driver. The article presents the information about the improvement, modernization of the tractor, the creation of various specialized modifications on its basis. DT-175S "Volgar" be-came the most powerful serial machine of the Volgograd Tractor Plant, rightfully earned the respect of specialists of farms and machine operators. (Conclusions). Further development of the application of the automatic hydro-mechanical transmission on agricultural tractors was to receive the VT-200D tractor of 5th traction class with a capacity of 147 kilowatts. Due to the complication of the economic situation, the production of this tractor was lim-ited to only a small experimental batch.

The Impact of Gender on Use of Cybercafé: A Survey of Cybercafé Users

2018 ◽  
Vol 8 (1) ◽  
pp. 80-86
Author(s):  
S. U. Shiva Kumara ◽  
B. T. Sampath Kumar
Keyword(s):  
Internet Services ◽  
Noisy Environment ◽  
Male And Female ◽  
Internet Connection ◽  
History Of ◽  
The Impact

The study aims to know the Impact of gender on the use of cybercafé. The study focused on the frequency and purpose of using cybercafé by male and female users. It also focused on the problems encountered by male and female users while using Internet at cybercafé. An aggregate of 450 copies of questionnaires were circulated to the cybercafé user, of which 416 properly filled questionnaires were returned. Data was analyzed using SPSS 21.0 version. It was observed that male users had a long history of using cybercafé than female counterparts (p<.000). The data also indicate that there is an association between the frequency of visit to the cybercafé and the gender (p<.000). High cost of Internet services (74.2%), noisy environment in and around the cybercafé (55.76%) and slow Internet connection (49.75%) at cybercafé were major problems faced by the cybercafé users.

Investigation of Hybrid Fuel Cell (HFC) Technology Applications on the Future Passenger Railroad Transportation

Joint Rail ◽  
2003 ◽  
Author(s):  
H. Moghbelli ◽  
Y. Gao ◽  
R. Langari ◽  
M. Ehsani
Keyword(s):  
Fuel Consumption ◽  
Fuel Economy ◽  
High Speed ◽  
High Efficiency ◽  
New Technologies ◽  
Positive Impact ◽  
Weak Link ◽  
Transportation System ◽  
Production Costs ◽  
Passenger Railroad

Due to the consideration of fragile security, and longer check-in times and inconveniences due to increased air travel security examination since September 11th 2001, more and more people have turn to ground transportation. Unfortunately, the inefficient, environment-unfriendly and unsafe passenger cars and buses are the only choices available for middle distance trips. Development of high efficiency, clean and high speed railroad passenger transportation system has become more necessary to overcome this weak link. In this paper, the applicability of hybrid drive train technologies for middle-distance passenger train locomotives will be investigated. A systematic design of the diesel based hybrid locomotive helps to increase efficiency, improve fuel economy, reduce emissions and also reduce mass production costs. Furthermore, professional management and maintenance of railroad train locomotives make such new technologies more practical than for road vehicles. The success of such transportation system will have a great positive impact on our social activities, quality of life, energy supply, environment and economy. A diesel based hybrid electric locomotive (HEL) with batteries or an ultracapacitor is an option to reduce fuel consumption and emissions and provide better performance and fuel economy. The reduced fuel consumption helps reduce the amount of pollutants released. Engineering estimation indicate that emissions will be reduced by 70% and fuel efficiency will be increased by at least 30% in hybrid locomotives.

High Speed Locomotive Development: A European Experience

2010 ◽  
Author(s):  
Janis Vitins
Keyword(s):  
Power Unit ◽  
High Speed ◽  
Propulsion System ◽  
European Experience ◽  
History Of ◽  
And Performance

Europe has a long history of high speed locomotive and power unit development. This paper focuses on these developments in Sweden, Germany, Switzerland and Spain starting from high speed locomotives for 125 mph and ending with the AVE S112 high speed power unit for 206 mph. The major technical objectives starting in the 1970’s were to increase the speed and performance, while reducing the axle load from typically 21t at 125 mph to 17t at ≥ 156 mph. Developments of the propulsion system and vehicle concepts took place in many incremental steps, constantly improving the performance of high speed services. It is shown how American high speed locomotives relate to these developments and how one can learn from the European experience going forward.

scholarly journals The history of national constructions of 1940 (by the example of the Ferghana Valley)

2020 ◽  
Vol 9 (1) ◽  
pp. 189-192
Author(s):  
Kabulzhan Makhamadzhanovich Nasritdinov
Keyword(s):  
20Th Century ◽  
High Speed ◽  
Hydraulic Structures ◽  
Irrigated Agriculture ◽  
Irrigation Canals ◽  
Soviet Government ◽  
Ferghana Valley ◽  
History Of ◽  
Agricultural Areas

Based on scientific, historical and archival sources the author of the paper analyzes the history of developing plans aimed at irrigation of virgin lands in the central part of the Ferghana Valley in the first half of the 20th century by large Russian scientists and specialists. The author also shows a historical picture of the construction of the irrigation facilities of the Ferghana Valley using the high-speed hashar folk method in 1940. With the construction of hydraulic structures such as the northern and southern Ferghana canals, a new stage began in the development of irrigated agriculture in the Ferghana Valley, since the water of these hydraulic structures made it possible to irrigate new virgin lands in the central part and foothill areas of the Ferghana Valley. But it should be noted that these large and complex irrigation canals were constructed by the peoples of Uzbekistan mainly with the use of primitive tools such as a hoe, a crow, a shovel, a stretcher and pickaxes. For nearly 80 years, these hydraulic structures have provided agricultural areas with life-giving water. The author of the paper also summarizes the essence of economic measures carried out by the Soviet government on the development of irrigated agriculture in the valley.

Railway Territorialities

Transfers ◽  
2020 ◽  
Vol 10 (2-3) ◽  
pp. 230-249
Author(s):  
Mateusz Laszczkowski
Keyword(s):  
Social Relations ◽  
High Speed ◽  
Social Space ◽  
Participant Observation ◽  
High Speed Rail ◽  
Ethnographic Fieldwork ◽  
History Of ◽  
Local Residents ◽  
Traffic Corridor ◽  
Transnational Space

This article examines transportation infrastructures’ capacity to produce and transform social space through a focus on the contested history of railway development in Valsusa, Italy. I draw on participant observation and interviews with local residents and activists during ethnographic fieldwork in 2014–2015. I first describe how railways helped form modern sociality in Valsusa in the twentieth century. Subsequently, I explore contrasting topological effects of a projected high-speed rail through the valley. For planners envisioning a trans-European space of exchange, the railway is a powerful way to “shrink” space; for local residents, this implies reducing Valsusa to a traffic “corridor.” Yet their protest generates new social relations and knowledges, giving rise to a notion of “territory” as unbound and connected to a transnational space of resistance to capitalist expansion.

Railway Territorialities

Transfers ◽  
2020 ◽  
Vol 10 (2-3) ◽  
pp. 230-249
Author(s):  
Mateusz Laszczkowski
Keyword(s):  
Social Relations ◽  
High Speed ◽  
Social Space ◽  
Participant Observation ◽  
High Speed Rail ◽  
Ethnographic Fieldwork ◽  
History Of ◽  
Local Residents ◽  
Traffic Corridor ◽  
Transnational Space

Abstract This article examines transportation infrastructures’ capacity to produce and transform social space through a focus on the contested history of railway development in Valsusa, Italy. I draw on participant observation and interviews with local residents and activists during ethnographic fieldwork in 2014–2015. I first describe how railways helped form modern sociality in Valsusa in the twentieth century. Subsequently, I explore contrasting topological effects of a projected high-speed rail through the valley. For planners envisioning a trans-European space of exchange, the railway is a powerful way to “shrink” space; for local residents, this implies reducing Valsusa to a traffic “corridor.” Yet their protest generates new social relations and knowledges, giving rise to a notion of “territory” as unbound and connected to a transnational space of resistance to capitalist expansion.

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