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    <title>Transport Research International Documentation (TRID)</title>
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    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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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>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
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    <item>
      <title>State-of-Charge Estimation of Supercapacitors: A Switched Systems Approach</title>
      <link>https://trid.trb.org/View/2511814</link>
      <description><![CDATA[State-of-charge (SOC) estimation of supercapacitors has been extensively studied in the literature, with most of the existing studies focusing on the SOC estimation of a single supercapacitor cell. However, in practical applications, supercapacitors are often connected to balancing circuits to eliminate cell imbalances. When the balancing circuit is activated, the system dynamics of the cell switches to a new mode, implying that the existing SOC estimation methods cannot be applied directly. In this article, the authors propose a switched systems approach to estimate the SOC of the cells. They model the switching system for the RC model of the supercapacitor with a switched resistor balancing circuit and carefully study the continuity of the state and the observability of the switched system. Then, the authors propose a switching observer and analyze its convergence property. They have also developed an experimental platform to verify the effectiveness of the proposed method, and the performance of the different observers is compared. The design of the observer gain is explained in the discussion.]]></description>
      <pubDate>Fri, 25 Apr 2025 16:12:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/2511814</guid>
    </item>
    <item>
      <title>Road Test of Selected Electrical Parameters of the Hybrid Vehicle Accumulation System</title>
      <link>https://trid.trb.org/View/1770772</link>
      <description><![CDATA[Increasing energy efficiency in hybrid electric vehicles is associated with the possibility of recovering some of the kinetic energy in the delayed movement phase and converting it to electricity, which can be used to charge batteries. It is structurally possible to implement by using an electric machine operating as a generator and an energy accumulation system. In addition to the widely used lithium-ion energy storage systems, nickel-metal hydride energy accumulation solutions are also an alternative. Battery systems are characterized by specific electrical parameters which include, among others: electrical capacity, open circuit voltage (cells), discharge/charge current, battery state of charge or power of the energy storage system. The article was aimed at determining these parameters of the nickel-metal hydride energy storage system. The actual characteristics of the above-mentioned electric battery indicators were obtained through the measurements carried out during road and bench tests with the use of research apparatus and research object (Toyota Prius the third generation). The tests showed that the battery voltage varied slightly from 203.42 … 203.98 V (cell voltage -14.49 … 14.57 V, link voltage -1.211 … 1.214 V). On the other hand, the values of the charge/discharge current were in a wide range (-87.57 … 132.74 A) and depended on road conditions. This parameter was largely dependent on the torque balance of electric machines (generator, electric motor), but it also had an impact on the battery state of charge and power. To determine the parameters, an electric model of the Three RC Network Model, powered from an open-circuit voltage source and consisted of three resistors and three capacitors, was used. This electric model was characterized by high accuracy (up to 2.93%) and described the behavior of the nickel-metal hydride system of energy accumulation in real conditions in a good way.]]></description>
      <pubDate>Mon, 22 Feb 2021 10:20:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/1770772</guid>
    </item>
    <item>
      <title>Low-cost bus seating information technology system</title>
      <link>https://trid.trb.org/View/1741212</link>
      <description><![CDATA[Public transport operators often struggle to provide a reliable and efficient transport service. A lack of comprehensive real-time operational data is often cited as a major cause for this state of things. In this study, the authors report on the design, implementation and testing of an Internet of Things-based system, named Bus Seating Information Technology system, which dynamically determines vehicle occupancy while the bus is in service. It uses an array of sensors for detecting events in the vehicle: infrared sensors ascertain whether passengers are entering or leaving the bus; force-sensitive resistors facilitate seat-occupancy detection; a Global Positioning System shield in conjunction with a Raspberry Pi microcomputer enables real-time tracking of the bus; and a USB camera connected to the same Raspberry Pi assist in cross-checking and validating the preceding information. The data collected is uploaded to an online IoT platform (thinger.io), through 3G or 4G if available, and can be visualised via an android app as well as through a desktop computer user interface. The planned functions of the system were tested in a 20-seater bus. Results showed that the system can track the vehicle location, as well as vehicle occupancy in real-time in most cases.]]></description>
      <pubDate>Tue, 29 Sep 2020 09:58:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/1741212</guid>
    </item>
    <item>
      <title>Emulation of Loss Free Resistor for Single-Stage Three-Phase PFC Converter in Electric Vehicle Charging Application</title>
      <link>https://trid.trb.org/View/1695361</link>
      <description><![CDATA[In this article, the modular three-phase ac–dc converter using single-phase isolated Ć uk rectifier modules for charging of electric vehicles is discussed. The converters are designed and analyzed for the continuous conduction mode (CCM). This article is based on a new concept of adaptive sliding-mode-based loss-free resistor (ASLFR). ASLFR is a control scheme, which allows dual aim of power factor correction along with tight voltage regulation; hence, the adopted topology serves as a fitting single-stage solution for balanced three-phase systems. Complete theory is developed for the application, and the effectiveness of the scheme is well-established. Various studies to confirm the robustness of the system to any load and line variation are carried out. Moreover, a qualitative analysis is also made to show the expediency of the proposed ASLFR. Simulation as well as experimental studies are claimed theoretically.]]></description>
      <pubDate>Mon, 27 Apr 2020 09:10:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/1695361</guid>
    </item>
    <item>
      <title>Imbalanced Load Regulation Based on Virtual Resistance of A Three-Phase Four-Wire Inverter for EV Vehicle-to-Home Applications</title>
      <link>https://trid.trb.org/View/1593841</link>
      <description><![CDATA[As a new application area of electric vehicles, vehicle to home (V2H) recently becomes one of the most attractive research areas. In this paper, a three-phase four-wire inverter using four half-bridge legs is adopted to realize the V2H functionality. Such three-phase inverter acts as the grid-side ac/dc part of the battery charger. In order to deal with the imbalanced load, an independently controlled neutral module has been adopted to form the neutral line and provide the path for the zero-sequence current, together with split dc-bus capacitors. Each phase employs the independent sinusoidal pulse width modulation control with the virtual resistor paralleled with the load, namely, notch-filter-incorporated capacitor voltage feedback control, which damps harmonics around the resonant frequency at various load conditions. In addition, this paper quantifies the load imbalance versus the dc-link voltage oscillation and provides the guidance for the selection of the dc-link capacitance. Finally, a 10-kW three-phase four-wire inverter working at the V2H mode is built and tested, with the three-phase imbalanced load imposed to validate the proposed design and control strategy.]]></description>
      <pubDate>Mon, 29 Apr 2019 09:28:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/1593841</guid>
    </item>
    <item>
      <title>Impact of Heating System on the Range of an Electric Vehicle</title>
      <link>https://trid.trb.org/View/1471748</link>
      <description><![CDATA[For an accurate evaluation of the driving range of an electric vehicle (EV), many conditions must be considered (road profile, traffic influence, etc.). However, a cabin heating system is not often considered despite its significant impact. In this paper, the impact of the cabin heating system is studied on the driving range of an EV. A real EV is used as a reference. A multidomain model is developed and validated by experimental results on the vehicle. From this validated model, the impact of the heating system on the range is evaluated up to 30% in cold climatic conditions. In a classical approach, an ecodriving mode enables an increase in the range by reducing the vehicle acceleration and velocity. When considering the heating system, the energy balance is more complex: the eco-driving mode can lead to an over-consumption of energy. A better compromise is required as a function of the climatic condition.]]></description>
      <pubDate>Tue, 29 Aug 2017 11:58:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/1471748</guid>
    </item>
    <item>
      <title>Numerical Simulation of a Road Deicing System Based on Resistor Network</title>
      <link>https://trid.trb.org/View/1477872</link>
      <description><![CDATA[This paper investigated the mechanism of resistor network for road deicing with finite element analysis. It also derived the differential equations and boundary conditions of a mathematical model during numerical analysis, applied load, achieved pavement and distribution temperatures, and observed the warming law within the structural layer at different power and environmental conditions. The temperature of the pavement and its structural layer was observed under the same experimental conditions with finite element analysis. Furthermore, the connecting network of the device was designed, and the temperature of the pavement and its structural layer obtained under the same experimental conditions with the finite element analysis. The experimental and numerical simulation results were in good agreement when compared, although a certain degree of error between the numerical simulation and experimental processes was found. Thus, finite element analysis and ANSYS were suitable for simulating the resistor network process of deicing, which is an unsteady heat conduction process. Results showed that this simulation provides a new method and basis for guiding the resistor network for road deicing engineering design and temperature control. The application prospects of this approach are broad.]]></description>
      <pubDate>Mon, 31 Jul 2017 16:33:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/1477872</guid>
    </item>
    <item>
      <title>Thin-Film Air Flow Sensors for Automotive using the MEMS Technologies</title>
      <link>https://trid.trb.org/View/1434327</link>
      <description><![CDATA[This paper presents two newly developed technologies of optimizing impurity diffusion concentration for silicon semiconductor material and controlling internal stress of the top SiN (Silicon Nitride) layer on a membrane of a silicon substrate to apply them to the manufacturing process of MEMS (Micro Electro Mechanical Systems) type air-flow sensor chips. Until today, in MEMS-type airflow sensors, poly-crystalline silicon (poly-Si) and platinum were widely used as a resistor material of key functional elements on a membrane of air-flow-rate measurement portion. The functional resistors on the membrane are required to monitor high temperatures of about 300 °C and to perform the self-heating operations at that temperature range because of the suppression of contaminant deposition by means of evaporation or incineration. However, the use of those resistor materials at such high-temperatures is very difficult because high-temperature use causes the problems of the sensing error expansion, the resistor material layer delamination etc. Therefore, we have developed a new MEMS-type air-flow sensor with high-temperature usable resistors which are formed in a single-crystal-semiconductor silicon of SOI (Single-crystal Si on insulator) substrate by applying a technique to optimize impurity diffusion concentration. In addition to the high-temperature use problem above, MEMS-type air-flow sensors have another problem that the membrane is fragile towards internal and external stress due to its extremely thin thickness. To solve this problem, we have developed a new technique to control the internal stress of the SiN layer of the membrane top surface using the LP-CVD (Low Pressure Chemical Vapor Deposition) method. Consequently, we have realized a new MEMS-type air-flow sensor with structurally strong membrane by making the SiN layer thicker.       ]]></description>
      <pubDate>Thu, 05 Jan 2017 16:23:09 GMT</pubDate>
      <guid>https://trid.trb.org/View/1434327</guid>
    </item>
    <item>
      <title>Battery State-of-Power Peak Current Calculation and Verification Using an Asymmetric Parameter Equivalent Circuit Model</title>
      <link>https://trid.trb.org/View/1412641</link>
      <description><![CDATA[In this paper, a higher fidelity battery equivalent circuit model incorporating asymmetric parameter values is presented for use with battery state estimation (BSE) algorithm development; particular focus is given to state-of-power (SOP) or peak power availability reporting. A practical optimization-based method is presented for model parameterization fitting. Two novel model-based SOP algorithms are proposed to improve voltage-limit-based power output accuracy in larger time intervals. The first approach considers first-order extrapolation of resistor values and open-circuit voltage (OCV) based on the instantaneous equivalent circuit model parameters of the cell. The second proposed approach, which is referred to as multistep model predictive iterative (MMPI) method, incorporates the cell model in a model predictive fashion. Finally, a SOP verification methodology is presented that incorporates drive cycle data to realistically excite the battery model. Simulation results compare the proposed SOP algorithms to conventional approaches, where it is shown that higher accuracy can be achieved for larger time horizons.]]></description>
      <pubDate>Tue, 28 Jun 2016 16:16:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/1412641</guid>
    </item>
    <item>
      <title>Perspectives on Logistics vs. SCM: A Survey of SCM Professionals</title>
      <link>https://trid.trb.org/View/813572</link>
      <description><![CDATA[There are multiple perspectives on the concept of supply chain management (SCM), despite some movement toward consensus on its definition, and SCM's association with logistics. The authors discuss results of a survey in which views of SCM in general, its barriers, and its facilitators, were given by SCM professionals. Broad, multi-functional SCM perspectives are generally preferred by those surveyed over narrower SCM perspectives. Rather than being technological, leading SCM implementation facilitators are relational. Additionally, rather than external (supplier and customer) resistance, employee or internal resistance appears to be the larger SCM implementation barrier.]]></description>
      <pubDate>Wed, 25 Jul 2007 07:39:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/813572</guid>
    </item>
    <item>
      <title>SUBWAY ENVIRONMENTAL SIMULATION PROGRAM AND SUBWAY ENVIRONMENTAL DESIGN HANDBOOK VALIDATION THROUGH FIELD TESTING. PART II OF IV: COMPUTER SIMULATION PROGRAMS. FINAL REPORT</title>
      <link>https://trid.trb.org/View/275655</link>
      <description><![CDATA[This technical report is Part II of IV of a project to validate by field tests specific portions of the Subway Environmental Simulation (SES) Computer Program and the Subway Environmental Design Handbook (SEDH) as they relate to underplatform exhaust systems; train-borne, naturally-convected resistor grid banks; stratification of air in high domed-roof subway stations; gravity-type, station dome relief vents; and the heat sink effect in stations. This report covers the description of the computer simulation programs being utilized; sources of program input data including data from previous field testing; typical computer input and output data; and specific comparisons of field-measured and computer-simulated data relative to train car resistor grid temperatures and station platform ambient air temperatures. General correlation was found between the measured and simulated resistor grid temperatures with the measured temperatures ranging to 20% below the simulated temperatures for current operating conditions. For 1990 conditions (higher train speeds, shorter station dwell times), the maximum difference reduced to about 15%. Less than a degree difference was found at one station between average field-measured and computer-simulated platform air temperatures. At a second station, the difference was five degrees with the measured temperature being the higher. Recomendations will be included in the final report.]]></description>
      <pubDate>Sat, 28 Aug 2004 04:41:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/275655</guid>
    </item>
    <item>
      <title>SUBWAY ENVIRONMENTAL SIMULATION PROGRAM AND SUBWAY ENVIRONMENTAL DESIGN HANDBOOK VALIDATION THROUGH FIELD TESTING. PART IV OF IV: FINAL REPORT</title>
      <link>https://trid.trb.org/View/273893</link>
      <description><![CDATA[This technical report is Part IV of IV of a project to validate by field tests specific portions of the Subway Environmental Simulation (SES) Computer Program and the Subway Environmental Design Handbook (SEDH).  No changes to the SEDH or SES computer program are recommended as a result of the testing programs covered by this project.  It was found that, in general, the high-domed, blunt-ended WMATA stations were sufficiently different from the station configurations used in developing the SEDH and SES computer program that field data relative to station air temperatures, velocities and direction did not correlate closely with calculated or computer-simulated data.  Since the WMATA station designs tend to be exceptions, it is not recommended that the SEDH and SES computer program be revised just to improve their applicability to these special designs.  While correlation was found relative to underplatform exhaust system efficiencies and train resistor grid temperatures, the field tests were not sufficiently conclusive to support changes to the SEDH of SES computer program.]]></description>
      <pubDate>Sat, 28 Aug 2004 04:14:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/273893</guid>
    </item>
    <item>
      <title>SUBWAY ENVIRONMENTAL SIMULATION PROGRAM AND SUBWAY ENVIRONMENTAL DESIGN HANDBOOK VALIDATION THROUGH FIELD TESTING. PART III OF IV: STATION STRATIFICATION AND HEAT SINK TESTS. FINAL REPORT</title>
      <link>https://trid.trb.org/View/273892</link>
      <description><![CDATA[This technical report is Part III of IV of a project to validate by field tests specific portions of the Subway Environmental Simulation (SES) Computer Program and the Subway Environmental Design Handbook (SEDH) as they relate to stratification of air in high, domed-roof subway stations; gravity-type, station dome relief vents; and the heat sink effect in stations. This report covers the field testing program and comparative computer simulations relative to air stratification in high, domed stations; effectiveness of station air conditioning systems; effectiveness of gravity-type dome reliefs; and the impact of the heat sink effect on station temperatures. The anticipated stratification of the air in the stations did not occur. The gravity-type dome relief systems were found to be not effective with actual air flows generally being much less than simulated flows. Tests of powered-type dome relief systems found air flows close to design flows with train piston action having little effect on these flows. The net heat sink effect over the ten-month test period was found to be almost nil. The net flow was .04 BTU/SF from the structure to the air. During evening rush hour, the heat sink effect amounted to approximately 4% (14 tons) of the station air conditioning load.]]></description>
      <pubDate>Sat, 28 Aug 2004 04:13:59 GMT</pubDate>
      <guid>https://trid.trb.org/View/273892</guid>
    </item>
    <item>
      <title>SUBWAY ENVIRONMENTAL SIMULATION PROGRAM AND SUBWAY ENVIRONMENTAL DESIGN HANDBOOK VALIDATION THROUGH FIELD TESTING. PART I OF IV: UNDERPLATFORM EXHAUST SYSTEM AND TRAIN BORNE RESISTOR GRID TEST PROGRAM. FINAL REPORT</title>
      <link>https://trid.trb.org/View/273891</link>
      <description><![CDATA[This technical report is Part I of IV of a project to validate by field tests specific portions of the Subway Environmental Simulation (SES) Computer Program and the Subway Environmental Design Handbook (SEDH) as they relate to underplatform exhaust systems; train-borne, naturally-convected resistor grid banks; stratification of air in high domed-roof subway stations; gravity-type, station dome relief vents; and the heat sink effect in stations.  This report covers the testing of the underplatform exhaust systems and train-borne, resistor grid banks.  To evaluate the performance of the exhaust systems, tests were performed on the installed systems in typical, operating stations in the WMATA subway system.  Data was concurrently collected on the resistor grid banks of the test train--their being the primary source of train-generated heat rejected to the stations.  This report describes the facility design and experimental program.  A presentation of test results and interpretations is included.  Test results are compared with corresponding SEDH data.  That a relationship exists between underplatform exhaust system efficiency and length of train dwell was confirmed.  However, the actual efficiencies were found to be much less than predicted by the SEDH.  Measured resistor grid temperatures were found to be within 15% of those predicted by the SEDH.  Recommendations will be included in the final report.]]></description>
      <pubDate>Sat, 28 Aug 2004 04:13:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/273891</guid>
    </item>
    <item>
      <title>THERMAL BEHAVIOR OF TRANSIT VEHICLE RESISTOR GRIDS</title>
      <link>https://trid.trb.org/View/10554</link>
      <description><![CDATA[The report was prepared under the Institute for Rapid Transit (IRT) project, 'Ventilation and Environment Control in Subway Rapid Transit Systems,' and is one of the many such reports leading to the final product -- a 'Subway Environmental Design Handbook.' The report describes a mathematical model and a corresponding computer subroutine which characterize the thermal behavior of transit vehicle acceleration and deceleration resistor grids. This subroutine is part of the Subway Environmental Simulation (SES) computer program and computes the instantaneous heat rejection rate from transit vehicle resistor grids. (Modified author abstract)]]></description>
      <pubDate>Fri, 31 Jan 2003 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/10554</guid>
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