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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>
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      <title>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>RAPID TRANSIT--THERE'S AN ELECTRIC BILL TO PAY</title>
      <link>https://trid.trb.org/View/27058</link>
      <description><![CDATA[This paper presents an argument for total system planning, prior to introducing new vehicles into a rapid transit system.  The electric bill can be overlooked in planning, but soon becomes a shocking reality.  Benefits and detriments to the electric system through operation of vehicles with various characteristics is discussed.]]></description>
      <pubDate>Sat, 19 Dec 1981 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/27058</guid>
    </item>
    <item>
      <title>TRANSIT SYSTEM ENERGY REQUIREMENTS</title>
      <link>https://trid.trb.org/View/31495</link>
      <description><![CDATA[The importance of energy conservation has been recognized by the engineering profession for some time, although this has been apparent to the general public only in recent months. As an alternative to the private automobile, the more extensive use of public transit is recognized as a conservation measure.  This paper analyzes various transit systems as to energy required per Passenger-kilometer, based on average trip length, both on a theoretical basis and from operating statistics.  An equivalent is developed for comparing energy from fuels and electrical power supplies.]]></description>
      <pubDate>Wed, 15 Jul 1981 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/31495</guid>
    </item>
    <item>
      <title>NEW YORK CITY TRANSIT AUTHORITY DESIGN GUIDELINES. POWER</title>
      <link>https://trid.trb.org/View/41450</link>
      <description><![CDATA[The Power Standards for new lines provide the basic concepts for the design of traction power systems for new routes. The Standards describe the criteria used for the determination of the power requirements, the parameters used in the selection of substation sites and the types of electrical equipment employed for the conversion of High Tension AC power to DC traction power. They include the techniques used to control the power system from one control point and the means by which each substation can be controlled in the event of a supervisory cable failure. The Standards also describe the methods employed to give maximum safety in the substations and on the railroad in case of faults or emergencies. These guides should prove helpful in the design of traction power systems for new routes.]]></description>
      <pubDate>Tue, 23 Jun 1981 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/41450</guid>
    </item>
    <item>
      <title>A NOVEL ICEBREAKER CONCEPT</title>
      <link>https://trid.trb.org/View/164531</link>
      <description><![CDATA[With the new concept the icebreaking process differs considerably from that with conventional icebreakers.  The main feature is the flat bottomed bow with a beam greater than that of the ship and with sharp edges at the sides. Curves of ice resistance and power required show the advantages of the new hull form.  The results of the model tests in open waters are compared with those of vessels with conventional shapes.  Order from NSFI as No. 22357.]]></description>
      <pubDate>Fri, 12 Jun 1981 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/164531</guid>
    </item>
    <item>
      <title>FAST, WIDE-BEAM GENERAL CARGO SHIPS</title>
      <link>https://trid.trb.org/View/167166</link>
      <description><![CDATA[In a recent research and development project, completed in 1979, Blohm and Voss AG, Hamburg, has investigated the possibility of reducing building costs by the adoption of short, broad ship forms of L/B = 5, B/T = 3, C sub B around 0.6 and Froude number around 0.25 for general cargo ships, taking as example a "favourable" and well systematised containership design.  Extensive and detailed hydrodynamic, structural and cost studies were carried out to determine the most suitable principal particulars i.e. shortest length and least power requirement for a given transportation performance.  The results of model tests of hull forms with low power requirement and good propeller flow properties are presented and discussed.  An objective cost comparison shows that a wide-beamed ship of C sub B = 0.65 and length about 160 m could be built about 20% cheaper than conventional designs of equivalent transportation capacity.  Order from BSRA as No. 54,847.]]></description>
      <pubDate>Thu, 21 May 1981 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/167166</guid>
    </item>
    <item>
      <title>ENERGY CONSIDERATIONS STUDY ON NAVAL SHIP FUEL CONSUMPTION VARIATIONS</title>
      <link>https://trid.trb.org/View/168463</link>
      <description><![CDATA[Speed-Power Margins are applied during the preparation of powering performance estimates for new U.S. Navy ship design.  This paper describes a study which was carried out in support of the U.S. Navy's Energy Conservation Program. The primary purpose of the study was to estimate, for new naval ships, the savings in ship fuel consumption and ship acquisition costs which might be achieved by the use of design power margin values which are smaller than those in the current Naval Sea Systems Command's Margin Policy.  A second, related purpose was to determine the risks, in terms of reduced probabilities of achieving design speed, that would be associated with the use of reduced power margin values.  The results of the study indicate that reductions in fuel consumption and acquisition cost can be achieved if a projected new naval ship is redesigned with a smaller value of power margin.  However, the results are shown to be dependent upon ship size constraints and upon the type of propulsion system.  The results of the study also indicate that, for a projected new naval ship, the use of a reduced design power margin value will be accompanied by a substantial decrease in the probability of achieving the design speed.]]></description>
      <pubDate>Thu, 21 May 1981 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/168463</guid>
    </item>
    <item>
      <title>MARINE DIESEL APPLICATION IMPEDIMENTS--AN ASSESSMENT OF SHIPOWNER OPINION</title>
      <link>https://trid.trb.org/View/156911</link>
      <description><![CDATA[This report, based on interviews with representatives of some twenty shipowners and operators, identifies and analyze problem areas in the wider application of diesel propulsion for U.S. flag oceangoing cargo vessels.  Factors discussed with the shipowners relate to shipyards, engine builders, cost assessment, fuel quality, power requirements, maintenance practices, reliability, automation, noise and vibration, auxiliary machinery and personnel.  The report is intended as the first phase of a larger study.]]></description>
      <pubDate>Sat, 29 Nov 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/156911</guid>
    </item>
    <item>
      <title>CURRENT DESIGN AND PERFORMANCE REQUIREMENTS--MEDIUM SPEED DIESELS FOR MARINE SERVICE</title>
      <link>https://trid.trb.org/View/151858</link>
      <description><![CDATA[The cost and decreasing availability of oil fuel have made American shipowners and operators realise that Diesel propulsion must be considered for most new shipbuilding programmes.  The power requirement for the new ships would appear to be generally under 25,000 shp, and thus well suited to the geared medium-speed Diesel installation with one or more engines driving one or more shafts. Controllable-pitch propellers would be advantageous in such installations, but fixed-pitch propellers may also be successfully applied.  The Author, of Transamerica Delaval Inc., briefly discusses this interest in the U.S. market for medium-speed Diesel installations, and describes in some detail his company's engines, the Enterprise R and RV, which were first introduced in 1954.  They now cover the power range from 3,000 shp to (in twin installations) 26,000 shp.]]></description>
      <pubDate>Wed, 08 Oct 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/151858</guid>
    </item>
    <item>
      <title>A NEW PROPULSION SYSTEM FOR SHIPS</title>
      <link>https://trid.trb.org/View/156186</link>
      <description><![CDATA[Contents: Executive Summary; Introduction--Limitation of Existing Propulsion Systems, Trends in Ship Power Requirements, Propeller Configuration, Supercavitating Propellers, Water Jet Propulsion, Integrate Ship and Propeller into a Single System; The New Propulsion System -- The Hydraulic Axial Flow Transmission, Pump -- Specific Speed and Efficiency, The Inverted Turbine, Integrated Transmission Turbine and Propeller, The Thrust Reaction System, Thrust Reversal, Combined Propulsion Efficiency and Transmission Ratio.  The Low Cavitation Pump, Boundary Layer Control on Propeller and Ship.  The Total System and Contra-Rotation; The Air Models; The Water Model; Propulsion System Performance; Propulsion Applications and System Improvements; Conclusions -- Proof of Concept, Future Applications and the Total Ship System.]]></description>
      <pubDate>Wed, 08 Oct 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/156186</guid>
    </item>
    <item>
      <title>ELECTRIC PROPULSION FOR OFFSHORE VESSELS</title>
      <link>https://trid.trb.org/View/151848</link>
      <description><![CDATA[This paper draws attention to recent developments in propulsion systems on specialty vessels dedicated to operations such as: a.  oil exploration; b. construction of ocean structures; c. pipelaying; d.  ocean mining; e. fire fighting and special services.  For very particular reasons the majority of these vessels are electrically powered in all major functions.  Critical to the successful performance of these vessels are a high degree of maneuverability and maximum operating economy.  Other important considerations in design of the total propulsion system are reliability, ease of operation and a minimum of maintenance.  A number of additional factors must be considered to develop an optimum integration of power generation, power consumption and power control systems.]]></description>
      <pubDate>Tue, 16 Sep 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/151848</guid>
    </item>
    <item>
      <title>MODEL TESTS IN ICE TO CONFIRM EFFECTIVENESS OF THE 140-FOOT WYTM AIR BUBBLER SYSTEM</title>
      <link>https://trid.trb.org/View/150933</link>
      <description><![CDATA[A 1/24th scale model of the 150 FT. WYTM was equipped with an air bubbler system. The bubbler system was operated at various flow rates from no flow to twice the nominal system capacity. Tests were performed in both solid ice and brash to determine the effectiveness of the bubbler system in reducing the power required to transit ice fields. In all cases, a flow was found which reduced the total power from that required for a ship without the air system. This model test formed the basis for designing the air bubbler system for the Coast Guard 140' class of icebreaking tugs. (Author)]]></description>
      <pubDate>Wed, 27 Aug 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/150933</guid>
    </item>
    <item>
      <title>NOTES ON THE THEORY OF HEAVE ATTENUATION</title>
      <link>https://trid.trb.org/View/155416</link>
      <description><![CDATA[This note examines the power required for heave attenuation of SEV, using either cushion air damping or flow modulating fans. Shortage of time has prevented a complete analysis of some aspects, particularly for the modulated flow case which is of most practical interest. Power requirements have been calculated for 100% heave attenuation only in the latter case and the values obtained are naturally very large. More work needs to be done on the partial alleviation case, which is of more practical interest. (Author)]]></description>
      <pubDate>Tue, 22 Jul 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/155416</guid>
    </item>
    <item>
      <title>INTEGRATED SHIP MACHINERY SYSTEMS WHICH RESULT IN SMALL, EFFICIENT DESTROYERS</title>
      <link>https://trid.trb.org/View/154057</link>
      <description><![CDATA[The use of properly selected integrated ship machinery systems can sharply reduce the size, installed power, and fuel consumption of future Destroyers without reducing payload, speed, range, margins, or stability.  One properly chosen subsystem opens the way to using a second superior subsystem, thus a third one, et cetra, forming a sort of beneficient chain reaction.  The superior subsystems themselves provide highly leveraged effects on the displacement of the ship.  Synergism of this entire chain can result in ships with markedly reduced initial and operating costs.  The most essential elements of this system are: aircraft derivative gas turbines; compact, lightweight electric transmissions; large battery energy storage systems; and contrarotating propellers.  Adoption of these systems permit secondary high-leverage subsystems to be used, including efficient ship service power from propulsion turbines and light-weight maintainable propulsion pods. These changes make total ship rearrangement possible, resulting in major decreases in turbine ducting, propulsion shafting, electric power distribution, and propulsion auxiliaries.  Similar benefits in the auxiliary machinery system result from adoption of reverse-osmosis fresh water production, heat pumps for space heating, glass-reinforced plastic piping, controllable-speed, high-efficiency pump motors, et cetera.]]></description>
      <pubDate>Thu, 26 Jun 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/154057</guid>
    </item>
    <item>
      <title>OPERATION OF A 2000 GALLON PER DAY REVERSE OSMOSIS DESALINATION SYSTEM ABOARD MONOB (YAG-61)</title>
      <link>https://trid.trb.org/View/150566</link>
      <description><![CDATA[A seawater reverse osmosis desalination plant rated for 2000 gallons per day output was installed and operated aboard the MONOB (YAG-61) for shipboard evaluation. The reverse osmosis plant produced 2200 to 3200 gallons per day of potable water when operated between pressures of 650 and 800 pounds per square inch gage, respectively. The diatomaceous earth prefilter performed reliably providing sufficiently high quality seawater filtrate to the reverse osmosis module. The overall reverse osmosis plant data after 480 operating hours showed no evidence of performance decline due to particulate fouling or calcium carbonate scaling. The reverse osmosis desalination plant power requirements aboard MONOB varied between 4.98 and 6.77 watt-hour per pound of freshwater produced. The fuel heat input requirements for a reverse osmosis plant were calculated to be 56 British thermal units per pound of freshwater for a ship that utilizes diesel electric generators, 91 British thermal units per pound for a ship that utilizes steam turbine generators, and 95.9 British thermal units per pound for a vessel that utilizes gas turbine generators. Procurement of a 12,000 gallon per day desalination plant is recommended along with a continuing technical effort on filtration and high-pressure pumps to achieve specific advanced performance goals. (Author)]]></description>
      <pubDate>Thu, 26 Jun 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/150566</guid>
    </item>
    <item>
      <title>TECHNICAL REQUIREMENTS FOR HIGH POWERED SINGLE SCREW PROPULSION OF MERCHANT SHIPS. VOLUME 1, EXECUTIVE SUMMARY</title>
      <link>https://trid.trb.org/View/138064</link>
      <description><![CDATA[MarAd announces the availability of a report prepared by Hydronautics, Inc. which describes the work done in assessing the technical requirements for high powered single screw propulsion of merchant ships.  Areas of investigation included the maximum power currently in use in single screw ships, the availability of high power components for ships, and problems encountered in service.  A complete bibliography is provided.  The collected data were analyzed, problem areas identified and the state-of-the-art determined.  Also identified was research necessary to extend the state-of-the-art allowing the design and construction of single screw ships of higher horsepower.]]></description>
      <pubDate>Wed, 07 Nov 1979 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/138064</guid>
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