<?xml version="1.0" encoding="utf-8"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>TRB Publications Index</title><link>http://pubsindex.trb.org/</link><atom:link href="http://pubsindex.trb.org/common/TRIS Suite/feeds/rss.aspx?tc=NN%3ACyma%2A" rel="self" type="application/rss+xml" /><description></description><language>en-us</language><copyright>Copyright © 2015. 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>TRB Publications Index</title><url>http://pubsindex.trb.org/Images/PageHeader-wTitle.png</url><link>http://pubsindex.trb.org/</link></image><item><title>A Tale of Two Cities: The Impact of Airline Mergers and Consolidation at London and New York</title><link>http://pubsindex.trb.org/view/1493054</link><description><![CDATA[This paper considers the changes to airline networks, service patterns, and competition that have taken place as a result of recent airline mergers on both sides of the North Atlantic as well as through transatlantic alliances. Capacity, frequency and the competitive position are studied at London and New York with the use of schedule data within different markets in which measures of market concentration are evaluated. International Civil Aviation Organization data is employed to examine load factors on international routes, and UK Civil Aviation Authority data to consider the distribution of traffic between airports in London. It is shown that the effectiveness of the hubs has increased, with enhanced efficiency for surviving airlines, through fewer competitors, an enlarged network and greater control of capacity. Potential concerns are identified however, regarding passenger choice, pricing, and service options that suggest the industry is moving toward an oligopoly. Smaller cities are also seen to be the losers from consolidation with slot divestments favoring increased service in the dense markets, with many regional links being axed altogether. The paper supplements the literature on airline consolidation, with a particular focus on the two biggest markets in the world—London and New York—which demonstrate some similar but also some different issues. Both airline network impacts and choice, and service for local consumers are considered.]]></description><pubDate>Mon, 25 Jun 2018 13:49:45 GMT</pubDate><guid>http://pubsindex.trb.org/view/1493054</guid></item><item><title>Airline Consolidation: Monopoly Power or Mature Industry?</title><link>http://pubsindex.trb.org/view/1426222</link><description><![CDATA[Market concentration in the U.S. airline industry today raises concerns about the airlines having too much market power, undoing the benefits that consumers have gained in the past three decades. Nevertheless, the U.S. Department of Justice (DOJ) had allowed five major airline mergers in the past 11 years, despite expressing concerns in some of the cases. The concerns expressed by DOJ and others have centered around five aspects of the U.S. airline industry: scope of consolidation, prices, output, profits, and market barriers. This article first describes each of these aspects and then explores the confounding factors behind them. Confounding factors include price transparency and ancillary fees; improved network efficiencies; market saturation; changes in U.S. income distribution; and increases in airline productivity.]]></description><pubDate>Fri, 21 Oct 2016 16:34:59 GMT</pubDate><guid>http://pubsindex.trb.org/view/1426222</guid></item><item><title>Airline Consolidation and Hub Abandonment: The Impact on Regional Economies</title><link>http://pubsindex.trb.org/view/1337617</link><description><![CDATA[Since the United States' 1978 Airline Deregulation Act, the legacy commercial air transport industry followed two significant and interdependent trends: hub-and-spoke network operations and air carrier consolidation. However, as airlines merge operations through consolidation, they rationalize routes, aircraft fleet and facilities to maximize efficiency and reduce costs. This includes abandoning redundant hub airports. This paper develops research to examine the question; What is the regional impact of hub abandonment due to airline consolidation? This paper utilizes a case study analysis of two abandoned airlines hubs, Pittsburgh International Airport and Lambert-Saint Louis International Airport, contrasted with two viable airline hubs, Minneapolis-Saint Paul International Airport and Charlotte/Douglas International Airport. Due to data availability covering a period of legacy airline consolidation the analysis includes 2000 through 2012 and utilizes three methods: input-output model, fixed-effects panel analysis and econometric comparison. A unique dataset is created from sources including airline passengers, air carrier flights, airport operations, air transport employment and regional gross domestic product. Further, the paper develops recommendations for airport operators and regional planners to understand and predict the economic impact of hub abandonment and develop policies to mitigate or leverage the regional impact.]]></description><pubDate>Fri, 16 Jan 2015 08:28:49 GMT</pubDate><guid>http://pubsindex.trb.org/view/1337617</guid></item><item><title>Capacity Discipline and the Consolidation of Airport Connectivity in the United States</title><link>http://pubsindex.trb.org/view/1288086</link><description><![CDATA[Airlines reduced available domestic capacity at airports across the United States from 2007 to 2012 in response to a global economic downturn and high and volatile fuel prices. More recently, despite an economic recovery and more stable fuel prices, airlines have continued to keep capacity low relative to historical levels in a strategy that has been referred to as "capacity discipline."  The effects of these shifts in capacity on airport connectivity to the global air transportation network remain unclear. This paper introduces an intuitive index to compute airport connectivity as a function of both the quantity and quality of scheduled nonstop and connecting service. Connectivity scores were computed for 462 U.S. airports; medium-hub and small-hub airports were found to have lost more connectivity on average than large-hub airports from 2007 to 2012. In multiairport regions, losses in connectivity at secondary and tertiary airports outpaced losses at primary airports. With lower levels of connectivity, smaller airports in these regions will need to employ creative strategies to prevent passengers from leaking to primary hubs. Whether these airports can recover from connectivity consolidation will also depend on how long the capacity discipline equilibrium remains in effect among U.S. airlines.]]></description><pubDate>Fri, 28 Feb 2014 13:32:28 GMT</pubDate><guid>http://pubsindex.trb.org/view/1288086</guid></item><item><title>North American Carsharing: 10-Year Retrospective</title><link>http://pubsindex.trb.org/view/882415</link><description><![CDATA[Carsharing (or short-term auto use) organizations provide members access to a fleet of shared vehicles on an hourly basis, reducing the need for private vehicle ownership. Since 1994, 50 carsharing programs have been deployed in North America—33 are operational and 17 defunct. As of July 1, 2008, there were 14 active programs in Canada and 19 in the United States, with approximately 319,000 carsharing members sharing more than 7,500 vehicles in North America. Another six programs were planned for launching in North America by January 2009. The four largest providers in the United States and Canada support 99% and 95.2% of total membership, respectively. A 10-year retrospective examines North America’s carsharing evolution from initial market entry and experimentation (1994 to mid-2002) to growth and market diversification (mid-2002 to late 2007) to commercial mainstreaming (late 2007 to present). This evolution includes increased competition, new market entrants, program consolidation, increased market diversification, capital investment, technological advancement, and greater interoperator collaboration. Ongoing growth and competition are forecast. Rising fuel costs and increased awareness of climate change likely will facilitate this expansion.]]></description><pubDate>Tue, 28 Apr 2009 08:08:59 GMT</pubDate><guid>http://pubsindex.trb.org/view/882415</guid></item><item><title>Freight Systems</title><link>http://pubsindex.trb.org/view/842280</link><description><![CDATA[This collection of 13 papers on freight systems addresses the following topics:  electronic freight theft management system; estimating freight volume shift in an international intermodal corridor; product recovery network design; multiproduct distribution network design; delivery consolidation in urban areas; estimating truck trip origin-destination; single allocation hub network design; integrated origin-destination synthesis model for freight; shipper preferences suggest strong mistrust of rail; rail freight as a means of reducing roadway congestion; dedicated truck facilities; spring highway load restrictions effect on freight flow; and impact of wide-base tires.]]></description><pubDate>Thu, 27 Dec 2007 09:30:45 GMT</pubDate><guid>http://pubsindex.trb.org/view/842280</guid></item><item><title>Evaluation of Delivery Consolidation in U.S. Urban Areas with Logistics Cost Analysis</title><link>http://pubsindex.trb.org/view/802192</link><description><![CDATA[One of the most promising strategies for reducing truck traffic in urban centers is the consolidation of consignments through cooperation and coordination among multiple businesses. However, various factors—including existing infrastructure systems, institutional and regulatory environments, socioeconomic and geographical characteristics, political climates, past and future changes in logistics and supply chain management, and market forces—will determine whether such a strategy can be adopted and function effectively in the United States. In this paper, the cost-effectiveness of a common type of consolidation scheme used in foreign countries is examined against the peddle-run system commonly used in the United States. The analysis results indicate that the current U.S. distribution system has substantial cost advantages. Demographic factors, population density, and urban area size, while having some effect on the logistics cost under the consolidation system, do not reverse the cost advantage of the peddle-run system within the range tested. The advantage of the peddle-run system will not be overcome without drastic policy changes, the imposition of truck size and weight restrictions, or investments in public terminals.]]></description><pubDate>Fri, 30 Mar 2007 07:02:16 GMT</pubDate><guid>http://pubsindex.trb.org/view/802192</guid></item><item><title>HAWAII'S EXPERIENCE WITH VERTICAL SAND DRAINS</title><link>http://pubsindex.trb.org/view/122590</link><description><![CDATA[SETTLEMENT OBSERVATIONS TAKEN ON TWO SAND-DRAIN PROJECTS WERE PLOTTED AND COMPARED WITH THE ESTIMATED TIME RATE OF SETTLEMENT. SETTLEMENT CALCULATIONS WERE MADE BY COMBINING THE SEPARATE PERCENT CONSOLIDATIONS DUE TO THE VERTICAL DRAINAGE AND THE RADIAL DRAINAGE OF THE PORE WATER. THE COEFFICIENT OF CONSOLIDATION FOR THE VERTICAL DRAINAGE OF THE PORE WATER WAS DETERMINED BY MEANS OF A LABORATORY CONSOLIDATION TEST. THE COEFFICIENT FOR THE RADIAL DRAINAGE OF WATER WAS COMPUTED FROM THE RESULTS OF FIELD PERMEABILITY TESTS AND FROM OBSERVATIONS ON THE RATE OF SETTLEMENT SHORTLY AFTER THE INSTALLATION OF SAND DRAINS. /AUTHOR/]]></description><pubDate>Sun, 15 Aug 2004 02:44:05 GMT</pubDate><guid>http://pubsindex.trb.org/view/122590</guid></item><item><title>LABORATORY INVESTIGATION ON THE USE OF HIGH MOISTURE CONTENT SOILS IN HIGH FILLS</title><link>http://pubsindex.trb.org/view/122468</link><description><![CDATA[A LABORATORY INVESTIGATION ON THE USE OF HIGH MOISTURE CONTENT SOILS IN HIGH FILLS IS DESCRIBED. THE PURPOSES WERE TO INVESTIGATE (1) THE EFFECT OF THIXOTROPY, INITIAL MOISTURE CONTENT AND DENSITY, AND CONSOLIDATION ON THE SHEAR STRENGTH OF CLAY-LIKE SOILS WITH MOISTURE CONTENTS UP TO 8 PERCENTAGE POINTS ABOVE OPTIMUM, (2) THE EFFECT OF INITIAL MOISTURE CONTENT AND DENSITY ON THE CONSOLIDATION CHARACTERISTICS OF THESE SOILS, AND (3) THE POSSIBILITY OF USING THESE SOILS IN HIGH FILLS AND THE MANNER IN WHICH THEY SHOULD BE USED. TWO SOILS - A DUNMORE SILT LOAM AND A CLARKESVILLE CLAY LOAM - WERE INVESTIGATED. SOIL SPECIMENS WERE FABRICATED BY STATIC COMPACTION AND LATER INVESTIGATED FOR SHEAR STRENGTH BY THE DIRECT SHEAR TEST AND FOR CONSOLIDATION CHARACTERISTICS BY THE CONVENTIONAL CONSOLIDATION TEST. THE RESULTS SHOW THAT, WHEN A SOIL IS CONSOLIDATED UNDER HIGH PRESSURES, THE INITIAL MOISTURE CONTENT AND DENSITY HAVE LITTLE EFFECT ON THE FINAL SHEAR STRENGTH. THIS LEADS TO THE CONCLUSION THAT HIGH MOISTURE CONTENT SOILS CAN BE USED IF THEY ARE PLACED IN THE LOWER PART OF A HIGH FILL AND IF SUFFICIENT TIME IS ALLOWED FOR THEM TO CONSOLIDATE. A PROCEDURE FOR USING THESE SOILS IN HIGH FILLS IS ALSO SUGGESTED. /AUTHOR/]]></description><pubDate>Sun, 15 Aug 2004 02:43:35 GMT</pubDate><guid>http://pubsindex.trb.org/view/122468</guid></item><item><title>PERFORMANCE STUDY OF CALCIUM CHLORIDE-TREATED ROADS</title><link>http://pubsindex.trb.org/view/122030</link><description><![CDATA[A SIXTEEN-YEAR PERFORMANCE STUDY WAS CONDUCTED OF CALCIUM- CHLORIDE-TREATED GRAVEL ROADS. A GRAVEL LOSS OF 23.5 CU. YD. PER MI. PER YR. FOR ROADS CARRYING FROM 41 TO 216 VEHICLES PER DAY WAS SHOWN. COMPARING THIS WITH LOSS REPORTED BY OTHERS FOR UNTREATED GRAVEL ROADS, IT APPEARS LOGICAL TO ASSUME A SAVING OF AT LEAST 50 CU. YD. OF GRAVEL PER MI. PER YR. BY MAINTENANCE WITH CALCIUM CHLORIDE. SAVINGS IN ANNUAL BLADING COSTS ARE ALSO REPORTED. THE CALCIUM-CHLORIDE, TREATED ROADS ARE STABLE IN ALL KINDS OF WEATHER, AND AT SIMILAR DRIVING SPEEDS PROVIDE A DEGREE OF SECURITY AND SAFETY EQUAL TO THAT PROVIDED BY OTHER TYPE SURFACES. A BRIEF HISTORY IS PRESENTED OF THE GRAVEL ROADS AND THE MEASUREMENTS MADE IN THIS PERFORMANCE STUDY. MAINTENANCE PRACTICES ON THESE ROADS ARE REVIEWED SHOWING: (1) THE CLEANING CULVERTS AND DRAINAGE DITCHES, (2) THE MAINTENANCE OF A SMOOTH MODIFIED A-SHAPED CROWN OF AT LEAST 0.5 IN. PER FT. TO PERMIT RAPID DRAINAGE OF SURFACE WATER TO THE DITCHES, (3) THE MAINTENANCE OF A CONSOLIDATED SURFACE FREE FROM FLOATING MATERIAL, AND (4) THE TREATMENT WITH CALCIUM CHLORIDE AS REQUIRED TO MAINTAIN A COMPACTED MOIST SURFACE.]]></description><pubDate>Sun, 15 Aug 2004 02:41:48 GMT</pubDate><guid>http://pubsindex.trb.org/view/122030</guid></item><item><title>CALCIUM CHLORIDE SURFACE-CONSOLIDATED ROADS</title><link>http://pubsindex.trb.org/view/122028</link><description><![CDATA[A DESCRIPTION IS PRESENTED OF THE CONSTRUCTION AND MAINTENANCE METHODS NECESSARY TO OBTAIN A SURFACE CONSOLIDATED ROAD. THE SURFACE STABILIZATION ROAD IS DENOTED BY MANY DIFFERENT TERMS INCLUDING PARTIAL STABILIZATION, SEMI-STABILIZATION, ACCELERATED TRAFFIC BOUND, MAINTENANCE WITH CALCIUM CHLORIDE, SURFACE COMPACTION, AND SURFACE CONSOLIDATION. NECESSARY CONSTRUCTION OPERATIONS ARE DESCRIBED WHEN ROADS LACK BINDER, AGGREGATE, MOISTURE, NEW ROADS, AND DRAINAGE AND CROWN. THE ADVANTAGES OF THIS TYPE OF SURFACE CONSOLIDATION ARE: (1) A VARIETY OF LOCAL SURFACING MATERIALS AVAILABLE IN MOST REGIONS CAN BE UTILIZED, (2) SPECIAL TECHNICAL KNOWLEDGE IS NOT REQUIRED IN THE SELECTION OF THESE MATERIALS, (3) THE COST IS LOW, AND (4) THIS ROAD TYPE FITS WELL INTO A STAGE CONSTRUCTION PROGRAM. /AUTHOR/]]></description><pubDate>Sun, 15 Aug 2004 02:41:48 GMT</pubDate><guid>http://pubsindex.trb.org/view/122028</guid></item><item><title>CONSTRUCTION ON MARSHLAND DEPOSITS: TREATMENTS AND RESULTS</title><link>http://pubsindex.trb.org/view/121703</link><description><![CDATA[FOUR FIELD CASES ARE EXAMINED OF POST-CONSTRUCTION SETTLE- MENTS OF STRUCTURES /BUILDINGS AND PAVED AREAS/ BUILT OVER COMPRESSIBLE ORGANIC SOIL DEPOSITS /MARSHLANDS/. LABORATORY TESTS SHOW THAT THESE SOILS EXHIBIT SUBSTANTIAL RATES OF SECONDARY COMPRESSION. ALL SITES WERE STABILIZED BY SURCHARGE FILLS, ONE SITE INVOLVED THE USE OF SAND DRAINS. TWO ADJOINING BUILDINGS ARE COMPARED, ONE WITH SAND DRAINS AND ONE WITHOUT. SURCHARGE SETTLEMENT RECORDS AND PIEZOMETER DATA ARE EVALUATED TO ESTIMATE THE EFFECTIVE CONSOLIDATION PRESSURES WHICH WERE ACHIEVED DUE TO SURCHARGING.]]></description><pubDate>Sun, 15 Aug 2004 02:40:28 GMT</pubDate><guid>http://pubsindex.trb.org/view/121703</guid></item><item><title>CONSOLIDATION PROPERTIES OF AN ORGANIC CLAY DETERMINED FROM FIELD OBSERVATIONS</title><link>http://pubsindex.trb.org/view/121347</link><description><![CDATA[A PROGRAM OF OBSERVATIONS OF SETTLEMENT AND PORE WATER PRESSURES WAS UNDERTAKEN IN A SOFT ORGANIC SILTY CLAY FOR CONTROL OF CONSTRUCTION OF A SECTION OF THE CHRISTINA RIVER INTERCHANGE OF DELAWARE INTERSTATE ROUTES I-95, I-495, AND I-295 NEAR WILMINGTON, DELAWARE. THE ROADWAY EMBANKMENT WAS STABILIZED BY USE OF VERTICAL SAND DRAINS PLUS SURCHARGE. VALUES OF COMPRESSION INDEX AND COEFFICIENT OF CONSOLIDATION COMPUTED FROM FIELD OBSERVATIONS WERE COMPARED WITH LABORATORY TEST DATA. UNDISTURBED SAMPLES OBTAINED AT A LATER TIME WHEN PRIMARY CONSOLIDATION WAS LARGELY COMPLETE WERE UTILIZED TO EVALUATE THE GAIN IN THE STRENGTH OF THE ORGANIC CLAY STRATUM. CONDITIONS DISCLOSED BY FIELD OBSERVATIONS AGREED REASONABLY WELL WITH THOSE ASSUMED FOR DESIGN. /AUTHOR/]]></description><pubDate>Sun, 15 Aug 2004 02:39:01 GMT</pubDate><guid>http://pubsindex.trb.org/view/121347</guid></item><item><title>COMPARISON OF LABORATORY AND FIELD VALUES OF CV FOR BOSTON BLUE CLAY</title><link>http://pubsindex.trb.org/view/121346</link><description><![CDATA[LABORATORY VALUES OF THE COEFFICIENT OF CONSOLIDATION FOR SWELLING FOR BOSTON BLUE CLAY ARE COMPARED WITH THE VALUE BACK-FIGURED FROM PIEZOMETER OBSERVATIONS AT A LARGE BUILDING EXCAVATION. THE FIELD VALUE IS SHOWN TO BE SIX TIMES LARGER THAN THE AVERAGE LABORATORY VALUE. POSSIBLE REASONS FOR THE LARGE DISCREPANCY BETWEEN THE LABORATORY AND FIELD VALUES ARE SAMPLE DISTURBANCE, ERRORS IN LABORATORY TEST PROCEDURES, ERRORS IN FIELD MEASUREMENT, AND THREE- DIMENSIONAL CONSOLIDATION EFFECTS. OF THESE FOUR ITEMS, ERRORS IN LABORATORY TEST PROCEDURES, PARTICULARLY THE DIFFICULTY OF MEASURING THE COEFFICIENT OF CONSOLIDATION FOR SWELLING FROM OEDOMETER TESTS, CAN CONTRIBUTE SIGNIFICANTLY TO THE DISCREPANCY. IN ADDITION, IT IS SHOWN THAT THREE- DIMENSIONAL CONSOLIDATION EFFECTS CAN ACCOUNT FOR THE DIFFERENCES BETWEEN LABORATORY AND FIELD VALUES. /AUTHOR/]]></description><pubDate>Sun, 15 Aug 2004 02:39:00 GMT</pubDate><guid>http://pubsindex.trb.org/view/121346</guid></item><item><title>HEURISTIC ANALYSIS OF IMPACTS OF COMMUTER RAIL STATION CONSOLIDATION ON PEDESTRIAN ACCESS</title><link>http://pubsindex.trb.org/view/729487</link><description><![CDATA[A mode-of-station-access survey at the Milwaukee District North Line Grayland and Mayfair Stations in Chicago is described.  The study was conducted to determine the impacts of consolidating these two stations into a single new station.  Patterns of different station access modes were studied.  The analysis focused on the most sensitive market segment--walkers.  Two different methods were used to determine how current walkers would be affected by such a station change.  The first estimate was based on changes in walking distances.  A heuristic procedure was developed to estimate the number of walkers currently using the system who would possibly walk to the proposed new station. This estimate assumed that stations would attract walkers from a circular area referred to as the catchment area.  The average walking distance to each station determined its catchment area size.  Further assumptions were made to predict those walkers who were not currently in the catchment areas but who would decide to walk to the new station.  This study provides intuitive results and methodology that show promise for use in similar situations.]]></description><pubDate>Wed, 24 Dec 2003 00:00:00 GMT</pubDate><guid>http://pubsindex.trb.org/view/729487</guid></item></channel></rss>