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    <title>Transport Research International Documentation (TRID)</title>
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>LONDON'S CENTRAL LINE PROTOTYPES ARRIVE</title>
      <link>https://trid.trb.org/View/277568</link>
      <description><![CDATA[Three all-aluminium trains designated 1986 tube stock are starting test running on London's Jubilee line.]]></description>
      <pubDate>Sat, 28 Aug 2004 04:48:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/277568</guid>
    </item>
    <item>
      <title>THEORETICAL AERODYNAMIC CHARACTERISTICS OF VEHICLES IN CONFINED SPACES</title>
      <link>https://trid.trb.org/View/17067</link>
      <description><![CDATA[The report has been prepared under the Transit Development Corporation (TDC) project, 'Ventilation and Environmental Control in Subway Rapid Transit Systems,' and is one of many such reports leading to the final product--a 'Subway Environmental Design Handbook.' It describes the results of a theoretical effort pertaining to the non-steady flow in a tunnel induced by a moving vehicle. A study is made of the entry problem and the problem of a vented tube.]]></description>
      <pubDate>Thu, 31 Jul 2003 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/17067</guid>
    </item>
    <item>
      <title>DATA ACQUISITION FOR VEHICLES IN CONFINED SPACES (VICS-70) FACILITY</title>
      <link>https://trid.trb.org/View/7410</link>
      <description><![CDATA[Tests were conducted at the VICs-70 facility using scale models under a variety of simulated conditions.  Model test data reduction procedures for steady-state tube vehicle aerodynamics are described.  Sample calculations of equilibrium velocity, drag coefficients, tube pressure gradient, tube flow velocity ratio, effective tube length and effective friction factor in proximity to the model are included.  Results of the test program are presented with reference to: velocity history; effects of model nose and tail perturbations on drag; drag as a function of blockage ratio, vehicle length, tunnel length, Reynolds number, and vehicle roughness, drag coefficient sensitivity to blockage ratio; and tube length and tube flow velocity ratio as a function of blockage ratio, vehicle length and test section length.]]></description>
      <pubDate>Sun, 09 Mar 2003 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/7410</guid>
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    <item>
      <title>EXPERT SYSTEMS AID FAULT DIAGNOSIS</title>
      <link>https://trid.trb.org/View/289567</link>
      <description><![CDATA[London Underground's commissioning of Logica to conduct a study to determine what contribution expert system technology could make to on-board fault diagnosis on tube trains is described.  The study was to focus on the relay-based brake circuit and the electric traction equipment.  It was found that the use of expert systems was both viable and attractive.]]></description>
      <pubDate>Tue, 31 Oct 1989 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/289567</guid>
    </item>
    <item>
      <title>THE COST STRUCTURE OF TUBE VEHICLE SYSTEM FOR HIGH SPEED GROUND TRANSPORTATION</title>
      <link>https://trid.trb.org/View/41251</link>
      <description><![CDATA[This report examines the estimation of capital and operating costs for a range of general assumptions concerning the physical and cost features of tube vehicle systems. Costs are broken down as follows: costs of land acquisition (right of way, land prices, the cost of land), tunnels, at-grade construction, overhead construction, track and control (investment and maintenance), station, terminal and yard, vehicle and crew, vehicle power and evacuation systems, (electricity, aerodynamic drag, magnetic suspension drag, evacuation systems); total and unit costs are quoted together with vehicle capacity and headways. The costs of the above parameters are incorporated in the economic case study of a hypothetical tube vehicle system for which total annual and unit costs are compared /TRRL/]]></description>
      <pubDate>Tue, 13 Jul 1982 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/41251</guid>
    </item>
    <item>
      <title>THE AERODYNAMICS AND VENTILATION OF VEHICLE TUNNELS - A STATE OF THE ART REVIEW AND BIBLIOGRAPHY</title>
      <link>https://trid.trb.org/View/59379</link>
      <description><![CDATA[The publication presents a state of the art review and bibliography on the aerodynamics and ventilation of road and rail tunnels, and also of underground rapid transit systems. The review discusses the subject in the following sections: road tunnels - the nature of the problem; effects of air pollution; the quantity of air required for efficient road tunnel ventilation; systems of road tunnel ventilation; instrumentation and control; planning of ventilation stations; economic considerations.  Rail tunnels and rapid transit systems underground - classification of tunnel systems; the thermal environment; the pressure and environment for both main line tunnels and RTSU; air quality in both main-line tunnels and RTSU; tunnel exit noise and vibration; possible future tube vehicle systems.  The bibliography contains details of 588 publications in four sections: (a) general and related references; (b) road tunnels; (C) motor vehicle exhaust emission, and (D) rail tunnels and other tube-vehicle systems. Two indexes to the bibliography are provided, the first by subject, tunnel name and country and the second by author.  /TRRL/]]></description>
      <pubDate>Sun, 27 Dec 1981 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/59379</guid>
    </item>
    <item>
      <title>PRELIMINARY STEADY-STATE SUBWAY AERODYNAMIC ANALYSIS (INCOMPRESSIBLE) - INTERIM REPORT</title>
      <link>https://trid.trb.org/View/132105</link>
      <description><![CDATA[FIVE ANALYTICAL MODELS ARE DEVELOPED FOR USE IN AN EXAMINATION OF THE AERODYNAMIC CHARACTERISTICS OF VARIOUS TUBE-VEHICLE SYSTEMS. MODEL I IS THE BASIC STEADY-STATE, INCOMPRESSIBLE THEORY WHICH GIVES A DETAILED DESCRIPTION OF THE NEAR-FIELD REGION ABOUT A VEHICLE TRAVELING A TUBE WITH NO VENTS OR INTERCONNECTIONS WITH OTHER TUBES. A COMPUTER PROGRAM TO CALCULATE AERODYNAMIC CHARACTERISTICS WITHIN THESE PARAMETERS HAS BEEN OPERATIONALIZED. MODEL II ASSUMES TUBE-VEHICLE SYSTEMS IN UNSTEADY OPERATIONS IN AN INCOMPRESSIBLE FLUID. IN THIS SITUATION, THE FLUID MOTION LAGS THAT OF THE DYNAMIC VEHICLE, AND CONSEQUENTLY ALTERS THE DRAG FORCE EXPECTED FOR THE STEADY-STATE CASE. MODEL II IS CONSIDERED A MORE REALISTIC DESCRIPTION OF SUBWAY SYSTEM CHARACTERISTICS, AND A COMPUTER PROGRAM FOR ITS APPLICATION HAS BEEN OPERATIONALIZED. MODEL III CALCULATES THE AERODYNAMICS OF A VEHICLE IN A VENTED SINGLE-TUBE SUBWAY CONFIGURATION, ASSUMING INCOMPRESSIBLE, STEADY-STATE MOTION. THIS REPRESENTS THE TYPICAL SUBWAY TUBE SYSTEM AND IS AN EXTENSION OF THE MODEL I FORMULAE TO INCLUDE THE EFFECTS OF VENTS TO ATMOSPHERE ALONG A SINGLE TUBE SEGMENT. MODEL IV CALCULATES THE AERODYNAMICS OF A VEHICLE IN A TUBE INTERCONNECTED TO A PARALLEL TUBE (BUT NOT VENTED TO ATMOSPHERE). A FIFTH MODEL IS USED TO EXAMINE THE AERODYNAMIC EFFECTS OF MULTIPLE VEHICLES IN STEADY-STATE MOTION; IN THIS FORMULATION, AN EXTRA NEAR-FIELD FLOW CALCULATION MUST BE MADE FOR EACH ADDITIONAL VEHICLE. THE THEORETICAL FORMULATION OF THE FIVE BASIC ANALYTICAL MODELS ALONG WITH SUPPORTING ANALYSIS OF THE EXPERIMENTAL DATA ARE DISCUSSED IN THE REPORT. /UMTA/]]></description>
      <pubDate>Sat, 07 Nov 1981 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/132105</guid>
    </item>
    <item>
      <title>EXPERIMENTAL AERODYNAMIC CHARACTERISTICS OF VEHICLES TRAVELING IN TUBES</title>
      <link>https://trid.trb.org/View/30408</link>
      <description><![CDATA[A simplified theoretical model for a vehicle traveling through an unvented tube under equilibrium incompressible conditions was used to guide the test program, reduce the data, and determine the self-consistency of the results. The results were then used to establish values for the arbitrary coefficients in the theoretical model. Substantial progress was made in understanding the aerodynamic characteristics of vehicles traveling in tubes as exemplified by the good agreement of the theoretical model predictions with the experimental data throughout the Reynolds number range (three orders of magnitude, up to that for an actual full-scale system) and the many geometric variables tested. (Author)]]></description>
      <pubDate>Wed, 04 Feb 1981 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/30408</guid>
    </item>
    <item>
      <title>PNEUMATIC TUBE TRANSPORTATION</title>
      <link>https://trid.trb.org/View/35899</link>
      <description><![CDATA[The results of basic research on the pneumatic tube system are used to project significant operating characteristics of a prototype pneumatic tube transportation system.  The projections are based on an experimentally verified, numerically computed analysis and laws of similitude. Background and other pneumatic tube studies are noted. Vehicle speed variations on the guideway due to air friction and compressibility during a transit are shown for the prototype double-tube system to be acceptable at moderate speeds.  Guideway power is shown to be strongly affected by vehicle average speed, to be essentially directly proportional to guideway discharge pressure, and to be little influenced by the vehicle weight.  The technical feasibility of the investigated features of the concept is supported.]]></description>
      <pubDate>Wed, 10 Mar 1976 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/35899</guid>
    </item>
    <item>
      <title>EVACUATED TUBE TRANSPORTATION, ENERGY AND THE ENVIRONMENT</title>
      <link>https://trid.trb.org/View/26136</link>
      <description><![CDATA[This preliminary study compares the relative merits of a 966 km/h HSGT system employing permenent magnet (PM) suspension and a subterranean, evacuated tube guideway, with a 483 km/h atmospheric surface system being considered for the NEC route.  The results indicate that the increased patronage of the higher speed system, would much more than compensate for the tunneled guideway expense.  Greatly superior profitability is accompanied by environmental advantages and perhaps as much as an order of magnitude less energy consumption.  Additionally, various magnetic levitation approaches are compared for evacuated tube systems.  Levitation energy battery requirements approximate one-seventh the vehicle weight and magnetic drag losses greatly exceed that for PM.  If more extensive PM system studies confirm these preliminary results and that track magentization adjustment frequency is reasonable, as expected, and no major unforeseen problems develop, an evacuated tube system should best employ PM levitation.]]></description>
      <pubDate>Wed, 26 Mar 1975 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/26136</guid>
    </item>
    <item>
      <title>THE FLEXIBILITY OF A TUBULAR WELDED JOINT IN A VEHICLE FRAME</title>
      <link>https://trid.trb.org/View/139959</link>
      <description><![CDATA[Automotive frames frequently consist of thin-tube members thick enough for much of the structure to be modeled adequately by bar elements.  However, previous results show that a typical welded joint cannot be handled by the classical "rigid joint" assumption of frame analysis.  Those results include tests of a joint type common in passenger car frames, and establish errors of over 60% in analytical predictions for some of the lower natural frequencies.  The present paper attempts to see how much improvement can be achieved by simply accounting for the actual tubular shape in the vicinity of the joint, without allowing for the flexibility of the weld line itself.  The study uses the NASTRAN computer program.  The joint region is treated as a small substructure in a model otherwise composed of bar elements.  This procedure is economical because only those portions which really have to be analyzed using plate elements are so treated.]]></description>
      <pubDate>Tue, 31 Dec 1974 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/139959</guid>
    </item>
    <item>
      <title>AIRBORNE IN A TUBE</title>
      <link>https://trid.trb.org/View/138591</link>
      <description><![CDATA[An experimental, industrial, pneumatic tube containerized transport line built to carry gravel from a quarry to a concrete products plant is described. Economic and engineering computations show that this form of transport is very efficient. A development which is based on air cushion principle is outlined for unloading containers in pipelines. The specially designed collar seal enables utilizing the air not only for moving the containers or trains but also for the unloading. The pneumatic tube containerized systems are primarily for transporting free-flowing cargo such as construction material, fertilizers, ore, slag and ashes. The benefits of such transportation in agriculture are discussed and its promising application in other fields are reviewed. They may be utilized in the development of oil and gas fields in Siberia, for removal of 700 million cubic meters of peat from swamps, in the coal industry, for the transport of sand, for the pick up and delivery of trash, and in the ferrous and nonferrous industries, as well as in construction.]]></description>
      <pubDate>Fri, 11 Oct 1974 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/138591</guid>
    </item>
    <item>
      <title>PASSENGER COMFORT LIMITATIONS ON THE DESIGN OF HIGH SPEED TRANSPORTATION SYSTEMS</title>
      <link>https://trid.trb.org/View/129744</link>
      <description><![CDATA[This document reviews some of the available information on the subjective reaction of passengers to various parameters (including noise, vibration and acceleration) of the vehicle environment. The information is discussed in terms of the design of a tube vehicle system for high speed ground transportation. Temperature and lighting are also considered in an attempt to present an overall technological view of the problems involved in evaluating discomfort tolerance, and in defining design criteria for comfort. /TRRL/]]></description>
      <pubDate>Fri, 11 Oct 1974 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/129744</guid>
    </item>
    <item>
      <title>EXPERIMENTAL AERODYNAMIC CHARACTERISTICS OF VEHICLES IN CONFINED SPACES</title>
      <link>https://trid.trb.org/View/137380</link>
      <description><![CDATA[This report was prepared under the Transit Development Corporation, Inc. (TDC) project entitled, "Ventilation and Environmental Control in Subway Rapid Transit Systems," and is one of the many reports leading to the final product---a "Subway Environmental Design Handbook."  Described are the results of the experimental effort pertaining to the aerodynamics of vehicles traveling in tubes, conducted in the Vehicles In Confined Spaces (VICS) 70 foot and 120 foot high small-scale test facilities at the Jet Propulsion Laboratory.  The theoretical counterpart of this report is "Theoretical Aerodynamic Characteristics of Vehicles in Confined Spaces".  The purpose of the experimental investigations was to develop sufficient understanding of the scaling considerations of subway train system aerodynamics to make, with the use of the theoretical models, adequate predictions for full-scale systems.  A great deal of high quality data has been obtained during the 2 years of testing.  According to the authors, progress has been made in understanding the aerodynamic characteristics of vehicles traveling in tubes, exemplified by the good agreement of the theoretical model predictions with the experimental data throughout the entire Reynolds number range and geometric variables tested.  Operational aspects are discussed and data presented and analyzed.  References and a bibliography are included and appendices are "Data Reduction" and "Simplified Theoretical Model for Tube Vehicle Aerodynamics (Incompressible, Steady-State, Single Vehicle, Unvented Tube."]]></description>
      <pubDate>Sat, 05 Oct 1974 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/137380</guid>
    </item>
    <item>
      <title>NEW TRANSPORTATION TECHNOLOGY</title>
      <link>https://trid.trb.org/View/140872</link>
      <description><![CDATA[A review of new transportation technology is presented. The degrees of freedom offered by various forms of transport are discussed, together with developments in new high-speed ground transportation technology (rail, tracked air-cushion or air-film vehicles, tube vehicles) and automatically controlled small vehicle systems. Brief details are given of the suspension, propulsion and guideway-type of each of these systems. The author concludes that the circulation needs in the central business district do not seem to be satisfied by any existing technology.]]></description>
      <pubDate>Sat, 05 Oct 1974 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/140872</guid>
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