scholarly journals Method for analysis and comparison in planning urban surface transport systems

2012 ◽  
Author(s):  
R. Bozzo ◽  
M. Canepa ◽  
C. Carnevali ◽  
R. Genova ◽  
G. Priano
Keyword(s):  
Urban Surface ◽  
Transport Systems ◽  
Surface Transport

STOL Aircraft—A Perspective

1968 ◽  
Vol 72 (685) ◽  
pp. 11-33 ◽  
Author(s):  
R. D. Hiscocks
Keyword(s):  
High Performance ◽  
Transport Systems ◽  
Total System ◽  
Operating Environment ◽  
Surface Transport ◽  
Transport Aircraft ◽  
Air Space ◽  
The Cost ◽  
Lifting System ◽  
Design And Manufacture

Summary The interest in Canada in the design and manufacture of utility aircraft with a short take-off and landing (STOL) performance may be traced back to the difficulties of surface transport in the early development of the country and the widespread use of bush aircraft. The leading characteristics of the STOL aircraft are examined with particular reference to design features essential to a short take-off and landing. The choice of powerplants and lifting systems is discussed with emphasis on the requirements for powered lift in the larger sizes of aircraft. The augmentor-wing is described as an example of an integrated propulsion lifting system with promise of a high performance. The phases of the take-off, transition, climb and landing manoeuvre are reviewed to illustrate the relative importance of various parameters in design and operation. The importance is stressed of good stability characteristics and effective controls for manoeuvring in a confined air space and a consistent landing performance. The requirements of a para-military mobile force tor a rapid response, deployment overseas and transportation in an area are examined. Some estimates are given of the probability of finding suitable airstrips in a particular region and the cost of constructing new airfields in a dynamic situation. The operating environment in potentially troubled areas of the world is examined briefly to provide guidance in design. The costs of a military supply system are discussed using various modes of transport which include trucks, helicopters, STOL and conventional transport aircraft with results which suggest that the system employing STOL aircraft in the tactical theatre has advantages in cost and effectiveness. Attention is drawn to the growing requirement for shorthaul, commuter and air taxi aircraft with STOL characteristics. Reference is made to the increases in air travel and the widespread use of large transport aircraft which have encouraged the movement of airports from urban centres at a time when city growth and congestion render surface transport increasingly difficult. The relative costs of commercial systems using the helicopter and STOL aircraft are examined. It is shown that the cost of STOL ports is not an excessive portion of total system costs when all factors are taken into account. Some forecasts are made as to future development trends in transport systems using STOL aircraft.

Airflow problems related to surface transport systems

1971 ◽  
Vol 269 (1199) ◽  
pp. 327-333 ◽  
Keyword(s):  
Ground Plane ◽  
Aircraft Design ◽  
Modern Society ◽  
Transport Systems ◽  
Transient Effects ◽  
Surface Transport ◽  
High Speeds ◽  
Moving Vehicles ◽  
Railway System ◽  
New Applications

Until comparatively recently surface transport engineering managed to get along reasonably well while paying only slight attention to aerodynamic problems. Speeds were low, and on the whole designs were determined by other considerations. But recent increases in the power, speed and size of vehicles, and the increasing dependence of modern society on transport systems that are completely reliable, have begun to focus attention on the need to devote more effort to understanding the movement of the atmosphere past moving vehicles, and over or through stationary portions of transport systems such as roads, bridges and tunnels. This paper aims to illustrate the problems that can arise in the field of surface transport. They tend to be in some ways more awkward than those encountered in the design of aircraft. The proximity of the ground plane, the frequent inability to introduce symmetry or two-dimensional geometry as simplifying factors and the emphasis on transient effects all make the analysis difficult to handle theoretically, or in some cases to explore experimentally. This being so, it is hardly a matter for surprise that the surface transport field is still relatively neglected, particularly in comparison with the more obviously glamorous field of aircraft design. Nevertheless, the sums involved in making an existing railway system perform satisfactorily at high speeds from an aerodynamic viewpoint may well be substantial. Tunnel ventilation will certainly become of increasing significance as tunnelling technology improves and as the falling cost of tunnelling opens up new applications for city transport and for road crossings of water and mountain barriers. And motorways in exposed places must be made as safe and weather-proof as knowledge permits. A case can certainly be made out for reconsidering our priorities in aerodynamic research.

The influence of operating loads on the state of stress and strain in selected load-bearing elements of a tower-type headgear structure / Wpływ obciążeń eksploatacyjnych na stan naprężenia oraz przemieszczenia wybranych elementów nośnych konstrukcji basztowej wieży szybowych

2012 ◽  
Vol 57 (3) ◽  
pp. 497-515
Author(s):  
Stanisław Wolny
Keyword(s):  
The State ◽  
Transport Systems ◽  
Load Bearing ◽  
Surface Transport ◽  
State Of Stress ◽  
Design Loads ◽  
Technical Specifications ◽  
Service Conditions ◽  
Safety Features ◽  
Actual Shape

Abstract The headgear structure allows the conveyance to be moved over the shaft top to the loading (unloading) point, at the same time it keeps in place the rope pulleys while tower-type headgear structures also accommodate the entire winder installations. The headgear is where the final stage of the hoisting installation is located and where the surface transport systems begin. These aspects strongly impact the actual shape of the tower, its height and in some cases determine the design of the entire winding gear. In order that all the headgear functions should be provided, it is required that the ultimate state conditions should be maintained throughout its entire service life. In order to assess the critical service conditions, the computation procedure should be applied based on design loads and fatigue endurance parameters. The computations of characteristic loads acting on the headgear structure use the developed model of the system based on the dynamic analysis carried out for a specific case: a hoisting installation operated in one of the underground collieries in Poland. The maximal and minimal loads acting on a Koepe pulley and those required for the system operation are determined accordingly. The laws of dynamics provide a background for finding the forces and moments of forces acting in the components of the driving system (including the electric motors and pulley blocks) for the specified loading of the Koepe pulley. Underlying the numerical FEM model of the tower-type headgear structure are the technical specifications of the analysed object and FEM calculations followed by endurance analysis to find the state of stress in structural elements of the headgear under the typical service conditions. The results help in assessing how the design of the hoisting installation should impact on safety features of load-bearing elements in the headgear structure.

Mars surface transport systems utilizing in situ hydrogen

2014 ◽  
Author(s):  
Robert L. Ash ◽  
Sean M. Hancock ◽  
Jake Tynis
Keyword(s):  
Transport Systems ◽  
Surface Transport

scholarly journals Mycobacterium abscessus Genetic Determinants Associated with the Intrinsic Resistance to Antibiotics

2021 ◽  
Vol 9 (12) ◽  
pp. 2527
Author(s):  
Mylene Gorzynski ◽  
Tiana Week ◽  
Tiana Jaramillo ◽  
Elizaveta Dzalamidze ◽  
Lia Danelishvili
Keyword(s):  
Gene Knockout ◽  
Efflux Pumps ◽  
Mycobacterium Abscessus ◽  
Transport Systems ◽  
Nontuberculous Mycobacterium ◽  
Genetic Determinants ◽  
Intrinsic Resistance ◽  
Surface Transport ◽  
Knockout Mutants ◽  
Molecule Transport

Mycobacterium abscessus subsp. abscessus (MAB) is a fast-growing nontuberculous mycobacterium causing pulmonary infections in immunocompromised and immunocompetent individuals. The treatment of MAB infections in clinics is extremely challenging, as this organism is naturally resistant to most available antibiotics. There is limited knowledge on the mechanisms of MAB intrinsic resistance and on the genes that are involved in the tolerance to antimicrobials. To identify the MAB genetic factors, including the components of the cell surface transport systems related to the efflux pumps, major known elements contributing to antibiotic resistance, we screened the MAB transposon library of 2000 gene knockout mutants. The library was exposed at either minimal inhibitory (MIC) or bactericidal concentrations (BC) of amikacin, clarithromycin, or cefoxitin, and MAB susceptibility was determined through the optical density. The 98 susceptible and 36 resistant mutants that exhibited sensitivity below the MIC and resistance to BC, respectively, to all three drugs were sequenced, and 16 mutants were found to belong to surface transport systems, such as the efflux pumps, porins, and carrier membrane enzymes associated with different types of molecule transport. To establish the relevance of the identified transport systems to antibiotic tolerance, the gene expression levels of the export related genes were evaluated in nine MAB clinical isolates in the presence or absence of antibiotics. The selected mutants were also evaluated for their ability to form biofilms and for their intracellular survival in human macrophages. In this study, we identified numerous MAB genes that play an important role in the intrinsic mechanisms to antimicrobials and further demonstrated that, by targeting components of the drug efflux system, we can significantly increase the efficacy of the current antibiotics.

City Competitiveness and Airport

2013 ◽  
pp. 61-83
Author(s):  
Maria Nadia Postorino
Keyword(s):  
Economic Growth ◽  
Information Science ◽  
Transport Systems ◽  
High Quality ◽  
Surface Transport ◽  
Capacity Enhancement ◽  
Space And Time ◽  
The City

Transport systems allow people to take part in social and working activities, which are variously spread in space and time. Cities where transport systems are widely developed benefit from a high-quality accessibility, which makes them more attractive both to users and investors. As a consequence, they can gain in competitiveness and economic growth. Particularly, an airport can play an important role in assuring the development of the city best linked to it, as it enlarges its external accessibility and attractiveness. As information science applications can be used to obtain more reliable, efficient and safer systems, with reference to these latter aspects this chapter describes the importance of improvements concerning surface transport systems linking cities to their nearest airports as well as improvements assuring safer operations and capacity enhancement at the city airport airside.

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