<rss version="2.0" xmlns:atom="https://www.w3.org/2005/Atom">
  <channel>
    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
    <description></description>
    <language>en-us</language>
    <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>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
    </image>
    <item>
      <title>Analysis of marketing efficiency on the example of Faraday future (Manufacturer of electronic machines)</title>
      <link>https://trid.trb.org/View/1867915</link>
      <description><![CDATA[Currently, in conditions of competition, high information load, the emergence of new consumer segments, differentiation of consumer requirements, the importance of identifying and forming competitive advantages that will provide a company with better market positioning, increased profits and customer loyalty increases. In a period of tougher market competition, the main task of companies is to create competitive goods or services; this corresponds to the modern provisions of the marketing concept. In this regard, modern companies have an increasing need to apply marketing tools for sustainable market behaviour and business efficiency. The purpose of this article is to analyse the current marketing activities of the company and develop proposals for the development of a real marketing model, taking into account the requirements of the modern market. The research target was Faraday Future, a growing electric vehicle company. This article explores the financial activities of Faraday Future, analyses the media activity of Lucid, Tesla, Faraday, presents an analysis of marketing results, presents the calculation of the coefficient of variation of sales for Faraday Future products, analyses the organizational structure of the marketing department, and proposes solutions to improve certain areas of marketing activities companies.]]></description>
      <pubDate>Tue, 24 Aug 2021 11:16:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/1867915</guid>
    </item>
    <item>
      <title>Detection Model for Unbalanced Bidding in Railway Construction Projects: Considering the Risk of Quantity Variation</title>
      <link>https://trid.trb.org/View/1848422</link>
      <description><![CDATA[The application of a unit-price contract is nascent in railway construction projects in China. The investment risks for owners arising from unbalanced bidding in unit-price contracts should be given significant attention. Many models have been developed to help contractors place unbalanced bids, making the work of detecting unbalanced bidding even more difficult, especially the quantity error exploitation type of unbalanced bidding. Most detection models fail to consider the risks of quantity variation, a frequent occurrence in railway construction projects. Accordingly, this study developed a model for detecting unbalanced bidding based on an unascertained measurement theory and a analytic hierarchy process–fuzzy comprehensive evaluation method. The proposed model considers the risks in quantity variations. A hierarchical structure model was established to calculate the risks in quantity variations from different line items. A case study was presented to demonstrate the use of the proposed models for identifying and detecting quantity error exploitation unbalanced bids in railway construction projects. The model proposes a method for detecting the quantity error exploitation type of unbalanced bidding in railway construction projects, and can effectively improve accuracy without requiring a large amount of data from previous projects.]]></description>
      <pubDate>Tue, 25 May 2021 16:20:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/1848422</guid>
    </item>
    <item>
      <title>Testing microsimulation uncertainty of the parcel-based space development module of the Baltimore PECAS demo model</title>
      <link>https://trid.trb.org/View/1756300</link>
      <description><![CDATA[A precise and stable microsimulation space development module is fundamental for supporting various policy decision-making exercises related to land development. This paper studies the dynamics or uncertainty of outputs of the parcel-based space development module of an integrated land-use and transport forecasting model—the Baltimore PECAS Demo Model. It is tested with two sub-studies: (1) running the model three times over the entire planning window from 2000 to 2030; and (2) running the model 30 times just one year ahead from 2000 to 2001. The outputs obtained are used to analyze such dynamics or uncertainty. Study results from the first sub-study show that, in general, the system is stable and consistent over runs and time, as supported by a set of paired t-tests. However, the coefficient of variation (COV) measuring the variation of estimated space quantity by category over four cross-section years indicates that the differences among runs are increasing over time through the planning window. The COV test over the second sub-study indicates the estimated space quantity is stable for most of the zones, except for a small portion of zones with a small space quantity.]]></description>
      <pubDate>Thu, 14 Jan 2021 13:39:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/1756300</guid>
    </item>
    <item>
      <title>Extreme responses and associated uncertainties for a long end-anchored floating bridge</title>
      <link>https://trid.trb.org/View/1714832</link>
      <description><![CDATA[Very-long floating bridges represent an innovative marine structure for crossing wide and deep fjords. During the design of a floating bridge, extreme structural responses at a specified probability of exceedance are required to be properly evaluated for ultimate limit state (ULS) design check. This study addresses the estimation of extreme structural responses due to wind and wave loads and associated uncertainties. An end-anchored floating bridge, about 4600 m, is considered in a case study. The long-term extreme responses are estimated by using a simplified engineering approach, in which the long-term extreme response is approximated by the one-hour short-term extreme responses at a high fractile (90% in this study) for selected short-term sea states. The extreme responses are expressed as μ+κ·σ, where μ and σ are the ensemble mean and standard deviation, and κ is a multiplying factor. Statistical analyses indicate that the structural responses, including axial force, strong and weak axis bending moments of the bridge girder, are close to follow a Gaussian distribution. A simplified analytical method, the Gumbel method and the mean upcrossing rate (MUR) method are employed to estimate the multiplying factor κ and extremes. The κ estimated by these three methods are generally close, varying in the vicinity of 4. The κ and extremes estimated by the simplified method have a much smaller variation than the Gumbel and MUR methods. Statistical uncertainties and model uncertainties in the extreme value prediction are also addressed. Based on the results of 10 sets of 10 1-h ensembles, the mean and coefficient of variation (CoV) of μ,κ,σ and extremes of structural responses of 10 1-h simulations under two selected sea states are evaluated. The CoV of σ is less than 0.045, but the CoV of κ is relatively large, mainly between 3.5×10-2 and 6.5×10-2. The CoV of extremes estimated by the simplified analytical method is fairly small, less than 0.035. While the CoV of extremes estimated by the Gumbel and MUR methods are much larger and can reach 0.137 and 0.158, respectively. In practical design of floating bridge, only a limited number of simulations (e.g. 10 1-h) are conducted to predict the extreme structural responses. This will introduce statistical uncertainties and should be corrected by a factor for a conservative estimate. A simplified procedure to derive the correction factor is presented in this study. For the floating bridge considered with 10 1-h simulations, the correction factor is recommended to be 1.1 when the absolute value of mean μ is smaller than σ, and be 1.2 when the absolute value of mean μ is larger than σ, in order to achieve a 90% conservative estimation of extreme.]]></description>
      <pubDate>Thu, 23 Jul 2020 16:16:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/1714832</guid>
    </item>
    <item>
      <title>Modeling and Optimization Algorithms in Ship Weather Routing</title>
      <link>https://trid.trb.org/View/1488309</link>
      <description><![CDATA[Efficient and sustainable sea transport is a key aspect to ensure cost competitive ship operation. The constant need to increase economic feasibility, energy efficiency and safety while complying with emission regulations motivates further developments and improvements in voyage optimization and weather routing systems. These systems optimize a voyage based on meteorological and oceanographic information taking into account ship characteristics and routing information. The quality of the provided route not only depends on the quality of this data, but also on the modeling of the optimization problem and the algorithm chosen to solve it. Due to the wide range of mathematical approaches and consequently challenges in decision making, this paper aims to give a comprehensive and comparative overview of the existing state-of-the-art methods by a thorough literature review and elaboration of different modeling approaches, optimization algorithms, and their application in weather routing systems. The research shows that approaches range from modeling the weather routing problem as a constrained graph problem, a constrained nonlinear optimization problem or as combination of both. Based on the formulation of the ship weather routing optimization problem different methods are used to solve it ranging from Dijkstra's algorithm, dynamic programming and optimal control methods to isochrone methods or iterative approaches for solving nonlinear optimization problems. However, it can be concluded that the determination whether an approach is suitable, produces sufficient results and may be recommended, strongly depends on the specific requirements concerning optimization objectives, control variables and constraints as well as the implementation.]]></description>
      <pubDate>Fri, 29 Dec 2017 09:59:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/1488309</guid>
    </item>
    <item>
      <title>Reliability Estimate of the Compaction Characteristics of Iron Ore Tailings Treated Tropical Black Clay as Road Pavement Sub-Base Material</title>
      <link>https://trid.trb.org/View/1419681</link>
      <description><![CDATA[A FORTRAN based first-order reliability program was employed to evaluate the suitability of tropical black clay (black cotton soil, BCS) - iron ore tailings (IOT) mixture compacted with British Standard light, BSL or standard Proctor (relative compaction = 100%) energy as road pavement sub-base material. Using regression models for compaction characteristics, and established distributions for the relevant soil parameters, reliability indices were computed. The results indicate that for the laboratory-based model, reliability index is sensitive to variability in all the soil parameters. Observed trends indicate that IOT content, silt content, sand content and specific gravity are greatly influenced by the coefficient of variation (COV) and therefore must be strictly controlled in IOT treated BCS for use as sub-base material. Clay content has little effect. Stochastically, the compactive effort used did not produce acceptable safety index value. Therefore, higher compaction energy and more potent additives such as cement or lime are recommended to model compaction characteristics of BCS-IOT mixtures for use as sub-base material in road pavement.]]></description>
      <pubDate>Wed, 21 Sep 2016 14:44:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/1419681</guid>
    </item>
    <item>
      <title>Simulation of mixed traffic flow on four-lane divided highways</title>
      <link>https://trid.trb.org/View/1114507</link>
      <description><![CDATA[This paper presents a complete methodology for analyzing mixed traffic on four-lane divided highways in India. An appropriate parameter for defining vehicle arrival patterns is found to be Coefficient of Variation (COV). The speed distributions are successfully defined by the concept of unimodal and bimodal distributions. Speed Dispersion Ratio (SDR) is a new parameter, which is introduced to quantify the effects of vehicular interactions in a mixed traffic stream on the speed distribution curves. Showing a significant influence on lane-usage, placement behaviour, and acceleration behavior of vehicles is the factor of shoulder conditions. In order to determine the capacity of four-lane divided highways for homogeneous types of traffic and for two vehicle categories at a time, a simulation program is also developed and runs were performed. Also estimated are Passenger Car Unit (PCU) values, and in order to determine the capacity of traffic mix for different shoulder conditions, a general equation is proposed. The effect on capacity and stream speed of traffic mix is discussed, in addition.]]></description>
      <pubDate>Mon, 29 Aug 2011 07:43:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/1114507</guid>
    </item>
    <item>
      <title>Solution Methods for Dynamic Offline Relaxation-Based O-D Estimation Problem</title>
      <link>https://trid.trb.org/View/847501</link>
      <description><![CDATA[The relaxation-based method was recently proposed to estimate origin-destination (O-D) travel demands from limited traffic measurements.  This method does not enforce the user equilibrium condition so that the difficulties associated with the traditional bi-level programming method are avoided.  This paper proposed a column generation procedure for solving the dynamic off-line relaxation-based O-D estimation problem which is formulated as a variational inequality (VI).  The VI problem encapsulates traffic flow dynamics through a dynamic network loading model.  It is shown that a space-time expanded network can be constructed to generate paths needed for solving the VI formulation optimally.   Algorithms for solving two key sub-problems: namely the restricted VI problem and the time-dependent minimum cost path problem, are presented and their implementation issues are addressed.  Numerical results based on synthetic data are also presented.]]></description>
      <pubDate>Tue, 03 Jun 2008 07:26:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/847501</guid>
    </item>
    <item>
      <title>Class of Normative Link Flow Control Problems in Transportation Networks</title>
      <link>https://trid.trb.org/View/848714</link>
      <description><![CDATA[It is well known that a general network economic equilibrium problem can be formulated as a variational inequality (VI) and solving the VI will result in a description of network equilibrium state. This paper, however, introduces a new class of normative control problem that requires the network equilibrium link flow to satisfy physical and/or environmental constraints, but without explicit definition of system optimal objectives. By applying the duality principle, this paper will formulate the problem as an inverse variational inequality (IVI) because the variables and the mappings in the IVI are in the opposite positions of a classical VI. The economics meaning of the dual variables (or Larangian multipliers) explains that the optimal solutions for such problems represent the shadow prices of the binding constraints. Since the solution algorithm of IVI only relies on the link-flow information, perfect knowledge of network demand and supply is not required for such problem. The problem is practical appealing since management authority is often required to maintain link-based level of services for paid users and explicit knowledge of network demand and supply is not available. We demonstrate the formulation and solution algorithms of such problems using an example of link-based road pricing.]]></description>
      <pubDate>Wed, 21 May 2008 07:05:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/848714</guid>
    </item>
    <item>
      <title>An Analytical Solution for the Finite-Horizon Pavement Resurfacing Planning Problem</title>
      <link>https://trid.trb.org/View/792863</link>
      <description><![CDATA[This paper presents an analytical approach for planning highway pavement resurfacing activities in the case of continuous pavement state and continuous time. It solves for the optimal resurfacing frequency and intensity that minimize life-cycle costs in a finite horizon. Optimality conditions are derived analytically, and a simple algorithm is developed to solve for the exact optimal solution. The optimal resurfacing strategy is found to be consistent with findings previously obtained by using an approximate approach and the strategy obtained for the infinite-horizon problem.]]></description>
      <pubDate>Tue, 07 Nov 2006 11:03:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/792863</guid>
    </item>
    <item>
      <title>Cordon-Based Congestion Pricing in a Continuum Traffic Equilibrium System</title>
      <link>https://trid.trb.org/View/759558</link>
      <description><![CDATA[In this study, a continuum equilibrium traffic assignment model is presented to identify cordon locations and charging levels for a cordon-based congestion pricing scheme for a monocentric city.  The traffic equilibrium model treats densely spaced roads as a continuum over which commuters are continuously dispersed. Suppose in the morning peak-hour, all commuters travel to the central business district (CBD) by taking their individual shortest routes. Their user-optimal route choice behavior, with or without toll pricing, can be formulated as a calculus of variations problem and solved efficiently by the modern finite element method. By plotting the numerical results in a two-dimensional space in the form of contour lines of travel cost to the CBD, one can intuitively identify the level of congestion and the external cost anywhere in the city.  The continuum model and two-dimensional numerical representation presented here allow a traffic planner to select easily one or multiple toll cordon(s) in the city and evaluate the impact of cordon toll charges on the resultant economic and user benefits.   A hypothetical example is used to demonstrate that the initial-cordon scheme, though undercharging the users, attains a net economic benefit that is very close to the first-best scenario.]]></description>
      <pubDate>Thu, 25 Aug 2005 14:24:51 GMT</pubDate>
      <guid>https://trid.trb.org/View/759558</guid>
    </item>
    <item>
      <title>THEORETICAL ANALYSIS ON THE VARIATION OF VALUE OF TRAVEL TIME SAVINGS</title>
      <link>https://trid.trb.org/View/742776</link>
      <description><![CDATA[Few theoretical studies have analyzed the variation mechanism of the concept of the value of time.  As a result it is not clear how travel and individual socioeconomic environments affect value of travel time savings (VTTS), making it difficult to explain the varied results observed in empirical studies.  This paper presents a theoretical examination on whether and how the VTTS changes with the travel and individual socioeconomic environments.  Following a review of basic theories of the value of time, a time allocation model for the general case of travel behavior is proposed.  Changes of VTTS with travel time, travel costs, wage rate, and work time are examined by the comparative static analysis under some general assumptions. The results provide the variation mechanisms of the value of time in general travel behavior, but also verify some results of empirical case studies. Differences between the variation of the VTTS and value of time as a resource are also discussed.  In addition to clearly distinguishing the two concepts, this research also shows that the two values might not be evaluated in the same way.  In some cases, the VTTS decreases although the value of time as a resource increases.]]></description>
      <pubDate>Thu, 21 Oct 2004 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/742776</guid>
    </item>
    <item>
      <title>THREE DIMENSIONAL ANALYSIS OF A MARINE RISER WITH LARGE DISPLACEMENTS</title>
      <link>https://trid.trb.org/View/440552</link>
      <description><![CDATA[A formulation to analyse the large displacement problem of a marine riser with two unequal principal moments of inertia of cross sections in three dimensional space is presented.  The method involves the utilisation of the equilibrium equations in the axial direction and the stationary condition of an energy functional.  The stationary condition of an energy functional. The co-ordinates X and Y, twisting angle F, and tension T are the four dependent variables, while the arc length s in the equilibrium state is the independent variable which is changed to depth Z in the numerical implementation.  A finite element method was developed to solve the problem of a riser with equal principal cross sectional moments of inertia.  An example is given.]]></description>
      <pubDate>Mon, 14 Aug 1995 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/440552</guid>
    </item>
    <item>
      <title>OPTIMIZATION OF VARIATIONAL METHODS</title>
      <link>https://trid.trb.org/View/450353</link>
      <description><![CDATA[Lord Rayleigh proposed his now classical method (based on a one-term deflection function) in 1870.  On the other hand, he suggested in 1894 the possibility of optimizing the eigenvalues (natural frequencies or buckling loads) by minimizing them with respect to an exponential parameter contained in the coordinate function.  This optimization approach has become increasingly popular in the last decade an it has been extended to other variational methods and bounding conditions.  This paper reviews recent developments in this area which consists, essentially, a nonlinear optimization process of the coordinate functions in a global sense.  The technique is applicable in a large variety of applied mechanics problems of considerable interest to ocean engineers dealing with the analysis of mechanical systems.]]></description>
      <pubDate>Mon, 14 Aug 1995 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/450353</guid>
    </item>
    <item>
      <title>A STUDY ON THE MINIMUM FUEL CONSUMPTION ROUTE</title>
      <link>https://trid.trb.org/View/388399</link>
      <description><![CDATA[Weather routing is one of the most effective approaches to the problem of saving fuel oil. In this paper, the optimal control laws of course and engine power to minimize the fuel consumption are derived from calculus of variations. Using those control laws, the performance curve of a container ship and simple wave field, and the properties of minimum fuel consumption route are investigated by numerical simulations.]]></description>
      <pubDate>Thu, 21 Jul 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/388399</guid>
    </item>
  </channel>
</rss>