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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>
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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>A Helical Compression Spring Fracture under Impact Velocity in Pump Operation by Theoretical Study and FEA</title>
      <link>https://trid.trb.org/View/2691988</link>
      <description><![CDATA[Helical compression springs have been used widely in various industries from automotive, aerospace and construction to electronics and medical devices. In the automotive industry, they appear in many places such as suspension, valvetrain, etc., as well in the discharge check valve of Gasoline Direct Injection (GDI) pump, which is the subject of study due to a recent fracture in lab testing.A theoretical study is conducted first to establish the equation governing spring dynamic motion under impact velocity, which can be in high magnitude with surging shock wave along spring axis. A new spring shock wave equation is developed for spring axial motion coupled with coil torsional effect. This newly derived shock wave equation has a broader term than the classic spring formula found in most engineering books. In this paper, it shows that the classic spring shock wave equation is only a special case for the general wave equation newly discovered. Then, a theoretical formula on spring shock wave propagation speed and natural frequency are presented, validated by a numerical simulation result by FEA on the spring natural frequency.Next, a FEA tool is employed to study the spring system under transient impact velocity, the spring dynamic stress at fracture location is obtained. It compares closely with the analytical approximate solution. Finally, a fatigue life assessment is performed, back up by the fractured part photo as well as the fatigue life cycles observed in testing. They are found in good agreement.]]></description>
      <pubDate>Tue, 14 Apr 2026 15:11:22 GMT</pubDate>
      <guid>https://trid.trb.org/View/2691988</guid>
    </item>
    <item>
      <title>Optimisation Model of SPD Supply Chain for Medical Consumables under DRG Background Based on Mixed Integer Programming</title>
      <link>https://trid.trb.org/View/2582661</link>
      <description><![CDATA[In the context of diagnosis related groups (DRG) payment systems, hospitals are facing dual pressures of controlling medical costs and improving service quality. The supply, processing and distribution (SPD) process of medical consumables is an important component of hospital operations, and optimising this supply chain can help achieve cost savings and efficiency improvements. This article proposed a medical consumables SPD supply chain optimisation model based on mixed integer programming (MIP), aiming to optimise the procurement, inventory and transportation strategies of medical consumables through scientific decision-making methods. The model construction comprehensively considered the cost control requirements and various constraints under the DRG system, including demand fulfilment, inventory capacity, supplier supply capacity and logistics transportation capacity. By using the solver CPLEX to solve the model, the results showed that the optimised supply chain strategy could significantly reduce total costs while improving supply chain service levels, with a demand fulfilment rate of up to 97%. The research in this article provides an effective optimisation tool for hospitals’ medical consumables supply chain management under the DRG payment system, with significant theoretical significance and practical application value.]]></description>
      <pubDate>Fri, 19 Sep 2025 16:58:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/2582661</guid>
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    <item>
      <title>Optimization of the distribution of hospital supplies during the Covid-19 pandemic under uncertainties</title>
      <link>https://trid.trb.org/View/2567442</link>
      <description><![CDATA[The novel coronavirus pandemic, a biological disaster, has increased the demand for medical supplies. In response, humanitarian logistics has become an important component in disaster management efforts, essential to relieving the suffering of those affected. The unpredictable nature of such crises makes planning these operations a challenge. In this context, mathematical models are crucial tools that support decision-making processes, ensuring effective logistics responses in disaster scenarios. This paper introduces a robust mathematical model designed to optimize the distribution of hospital supplies in scenarios with varying demand. The model serves as a strategic decision support tool by integrating facility location and vehicle allocation, incorporating parameters such as facility opening costs, transportation, travel times, urgency levels, fleet heterogeneity, and the optimal number of trips. Real-world data from five municipalities in Rio de Janeiro, Brazil, were used to validate the model during the Covid-19 pandemic. Computational experiments demonstrated that the robust model effectively balances costs and logistics performance, with total costs increasing by up to 42.7% in medium demand scenarios and decreasing by up to 15.4% in high demand scenarios, depending on the probability of occurrence and risk aversion. The model presents a conservative solution that accommodates different demand scenarios and provides better performance compared to deterministic solutions obtained from the average demand.]]></description>
      <pubDate>Mon, 21 Jul 2025 08:51:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/2567442</guid>
    </item>
    <item>
      <title>Buying from a rival: The effect of knowledge sharing, co-opetition and signal inference</title>
      <link>https://trid.trb.org/View/2567339</link>
      <description><![CDATA[The COVID-19 pandemic has put tremendous pressure on the global supply of critical medical devices such as ventilators, driving automakers to cross over to manufacture ventilators. However, it is not easy for these entrants to suddenly switch to the high-end medical devices (e.g., high-end ventilators) manufacturing since they lack the critical knowledge and key components. Interestingly, the authors observe that the entrants may be helped by the incumbent manufacturers, resulting in a co-opetition relationship where the former acquires the critical knowledge and key components from the latter. Intuitively, knowledge sharing may be rewardful for both the incumbent and entrant manufacturers because this strategy benefits the incumbents’ key components wholesaling business and induces the entrants to be informed as well. However, this intuition may be altered in a co-opetitive structure because of the signal inference. Being aware of this, in a co-opetitive supply chain comprising an incumbent manufacturer and an entrant manufacturer, they study the incumbent manufacturer’s preference over knowledge sharing. Furtherly, they also identify both “win–win” zones and “lose-lose” dilemmas for the two co-opetitive manufacturers.]]></description>
      <pubDate>Mon, 30 Jun 2025 09:19:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/2567339</guid>
    </item>
    <item>
      <title>Optimization and Regression Modeling of Fused Deposition Modeling for TPU Material Used in Automotive Instrument Panels</title>
      <link>https://trid.trb.org/View/2511113</link>
      <description><![CDATA[Fused Deposition Modeling (FDM) is a widely recognized additive manufacturing method that is highly regarded for its ability to create complex structures using thermoplastic materials. Thermoplastic Polyurethane (TPU) is a highly versatile material known for its flexibility and durability. TPU has several applications, including automobile instrument panels, caster wheels, power tools, sports goods, medical equipment, drive belts, footwear, inflatable rafts, fire hoses, buffer weight tips, and a wide range of extruded film, sheet, and profile applications.. The primary objective of this study is to enhance the FDM parameters for TPU material and construct regression models that can accurately forecast printing performance. The study involved conducting experimental trials to examine the impact of key FDM parameters, such as layer thickness, infill density, printing speed, and nozzle temperature, on critical responses, including dimensional accuracy, surface quality, and mechanical properties. The utilization of design of experiments (DOE) methodology enabled a methodical exploration of parameters. Statistical techniques were employed to develop regression models that establish relationships between process parameters and performance indicators. These models offer a prognostic instrument for optimizing FDM parameters and attaining desired printing results. The results demonstrated the effectiveness of the regression models in accurately forecasting the printing performance for TPU material. The models provide valuable insights into the optimal parameter configurations for maximizing printing efficiency, quality, and mechanical robustness. This study enhances the comprehension of Fused Deposition Modeling (FDM) for Thermoplastic Polyurethane (TPU) material and provides useful techniques for optimizing the manufacturing process. Manufacturers can improve printing productivity and quality by utilizing regression models, thereby promoting the wider use of FDM technology in industries that need flexible and durable components.]]></description>
      <pubDate>Tue, 18 Feb 2025 14:58:47 GMT</pubDate>
      <guid>https://trid.trb.org/View/2511113</guid>
    </item>
    <item>
      <title>Effect of Single Vacancy Defect on Fundamental Frequency of Single Walled Carbon Nanotube</title>
      <link>https://trid.trb.org/View/2511080</link>
      <description><![CDATA[This paper studies the effect of single vacancy defect on the fundamental frequency of carbon nanotube using finite element method. Cantilevered and bridged boundary conditions have been used for carbon nanotube with and without attached mass. There is less effect on the frequency of cantilevered structure due to presence of defect at center rather than its presence at other positions. Presence of defect near to fixed end shows more effect on fundamental frequency of bridged structure as opposed to other positions. Cantilevered structure with mass attached shows increase in effect due to presence of defect when mass ranges from 10-3 to 10-6 femtogram, while it seems to remain constant with further decrease in mass. This paper is mainly concerned about the overall effect of single vacancy defect at the different positions and with different parameters of carbon nanotube with and without attached mass on the frequency and frequency shift. Nano materials are playing a vital role in all the sectors. Particularly nano materials are used in automotive industries in a wide range such as as reinforcement materials in vehicle Production, fuel component system to increase the fuel efficiency etc. Use of SWCNTs and DWCNTs in tires allows significant improvement in their stiffness, tear resistance, fuel efficiency and grip, printable, thermoform able, capacitive touch sensors for replacing membrane switches in automotive interiors (as well as in white goods and medical equipment and devices).]]></description>
      <pubDate>Tue, 18 Feb 2025 14:58:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/2511080</guid>
    </item>
    <item>
      <title>Recommendations for Updates to Emergency Medical Kits for Commercial Aviation</title>
      <link>https://trid.trb.org/View/2447211</link>
      <description><![CDATA[Emergency medical kits (EMK) are provided to clinicians who volunteer on commercial aircraft during a medical emergency. The contents of the EMKs are mandated by the Federal Aviation Administration in the United States and, internationally, by the International Civil Aviation Organization and the country of airline origin. The mandatory contents of the kits have not been updated by the Federal Aviation Administration since 2006, and the EMKs continue to lack key equipment such as automated blood pressure cuffs, glucometers, pulse oximeters, and epinephrine autoinjectors. Of further concern is a lack of standardized and centralized reporting for in-flight medical events that, if it existed, could better inform the contents of the kits. This commentary is intended to advocate for an update to the EMKs in the United States given the authors’ experiences with in-flight medical events.]]></description>
      <pubDate>Fri, 22 Nov 2024 14:27:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/2447211</guid>
    </item>
    <item>
      <title>Coast Guard: Information on Medical Facilities</title>
      <link>https://trid.trb.org/View/2441684</link>
      <description><![CDATA[The U.S. Coast Guard, a military service within the Department of Homeland Security (DHS), is responsible for 11 statutory missions, including drug interdiction and search and rescue. In support of its missions, the Coast Guard provides certain health care services, such as annual physical examinations and immunizations, to approximately 47,000 active-duty and reserve personnel. The Coast Guard provides these services in coastal locations and on certain ships, such as vessels that deploy for multiday operations to help ensure Coast Guard personnel medical readiness. The majority of Coast Guard medical facilities are managed as part of its shore infrastructure. The shore infrastructure includes piers, docks, and boat stations at more than 20,000 government-owned or - leased Coast Guard onshore facilities at more than 3,000 locations. A smaller number of Coast Guard medical facilities are located on vessels and are thus managed as part of such vessels. The James M. Inhofe National Defense Authorization Act for Fiscal Year 2023 includes a provision for the Government Accountability Office (GAO) to study Coast Guard medical facilities. GAO is providing information on the overall condition and management of Coast Guard medical facilities and how it manages the medical equipment for each medical facility.]]></description>
      <pubDate>Thu, 07 Nov 2024 14:55:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/2441684</guid>
    </item>
    <item>
      <title>Rad Bett Sessel–An Integrated Wheelchair Bed for Incorporating
          Ergonomics into Mobility and Rest</title>
      <link>https://trid.trb.org/View/2348426</link>
      <description><![CDATA[The “Integrated Wheelchair Bed” is an innovative assistive technology designed to                     address the unique needs of individuals with mobility challenges. This duality                     concept is born out of a deep understanding of the daily challenges faced by                     those who require mobility aids for transportation and also need to rest                     periodically throughout the day, allowing for seamless transitions between                     mobility and rest. This dichotomy promotes both physical well-being and                     emotional independence, enhancing the overall quality of life for users. The                     need for a new wheelchair bed hybrid arises from evolving user requirements,                     such as improved comfort, compactness, customization, safety, technology                     integration, cost-efficiency, durability, versatility, aesthetics, healthcare                     integration, and sustainability. To overcome these problems, we have proposed a                     wheelchair that can be transformed into a bed using a two-bar linkage with a                     slot lock mechanism. The two-bar linkage facilitates the easy conversion system                     without much effort and any assistance. The slot lock mechanism is used to                     adjust and arrest the backrest which ensures the user’s safety during positional                     transitions. In addition to this, Castor wheels with braking systems are used to                     keep the wheelchair from moving on uneven terrain. Rigorous feasibility testing                     and user feedback gathered at medical camps underscore our commitment to                     user-centric innovation, ultimately aimed at enhancing the independence and                     overall quality of life for individuals with mobility challenges.]]></description>
      <pubDate>Mon, 04 Mar 2024 16:07:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/2348426</guid>
    </item>
    <item>
      <title>A Cold Chain Medical Device Distribution Path Optimization Method</title>
      <link>https://trid.trb.org/View/2319855</link>
      <description><![CDATA[The continuous development of the medical device industry has brought about strong demand for medical device logistics. Medical device transportation enterprises are faced with the dual tasks of cost and distribution time in their development. In this paper, a targeted cold chain distribution path optimization model is established based on the timeliness of medical device cold chain transportation for two types of customers. The model’s objective is to optimize the combination of cost and customer time satisfaction, considering the refrigeration energy cost and the carbon emissions cost of vehicle fuel combustion in the cold chain transportation process. In this paper, a fast non-dominated ranking algorithm with an elite strategy is chosen and solved for a real case, and the corresponding sensitivity analysis is performed. The results show that the time windows will significantly impact the overall distribution cost. This can be used to propose targeted management advice for actual cases.]]></description>
      <pubDate>Tue, 27 Feb 2024 16:40:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/2319855</guid>
    </item>
    <item>
      <title>Optimization of Multi-Cycle Distribution Center Location in the Context of an Epidemic</title>
      <link>https://trid.trb.org/View/2319838</link>
      <description><![CDATA[Due to its strong infectivity and pathogenicity, the outbreak of public health, such as plague, has exerted a great impact on the global human life and economic development. However, such measures will greatly affect the transportation and distribution of residents’ basic living supplies and epidemic-related medical supplies. Therefore, it is necessary to establish corresponding emergency distribution centers within the city to meet residents’ living and epidemic prevention needs. This paper analyzes the influencing factors and characteristics of the emergency distribution center in the outbreak, considers the periodic period of the change in the demand of the material, creates the multi-cycle distribution center location model of the situation, and discusses the algorithm of the problem and the application of the present situation in the present situation. In the process of the application, the disease control and control situation of Hefei city is divided into four periods, and the corresponding location is made for different requirements of each period of the virus, a large-scale outbreak, taking the effective isolation method such as traffic control after improvement, as confirmed cases of rehabilitation for dynamic zero finally.]]></description>
      <pubDate>Fri, 23 Feb 2024 16:23:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/2319838</guid>
    </item>
    <item>
      <title>Risk Assessment of Epidemic Prevention Materials Delivery Based on Bayes-OWA</title>
      <link>https://trid.trb.org/View/2237751</link>
      <description><![CDATA[This study aims to identify the risk factors in delivering epidemic prevention materials in the post-epidemic era and propose a method to estimate the risk probability and consequence. The risk assessment system with different characteristics of epidemic prevention materials was identified, and the Bayes-OWA method was applied to identify the key risk factors. Bayesian network (Bayes) is applied to characterize the causal hierarchical relationship between risk factors. Based on posterior probability and conditional probability analysis, the Ordered Weighted Average operator (OWA) is introduced to describe and rank the multiple attributes of risk factors. The model was carried out by ShuYu Civilian Pharmacy Corp. Ltd. The results showed that the risk of disinfection and cleaning in the delivery process is the key factor affecting the delivery risk. It provides a new idea for delivery risk management in the post-epidemic era and is significant to logistics safety management during the epidemic.]]></description>
      <pubDate>Tue, 30 Jan 2024 09:23:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/2237751</guid>
    </item>
    <item>
      <title>Identification of priority areas for public-access automated external defibrillators (AEDs) in metropolitan areas: A case study in Hangzhou, China</title>
      <link>https://trid.trb.org/View/2157481</link>
      <description><![CDATA[Out-of-hospital cardiac arrest (OHCA) is a major health concern in China. The use of automated external defibrillators (AEDs) has received great attention from Chinese public healthcare departments as a useful intervention to address OHCA, and there is a growing need to place AEDs throughout the urban built environment. However, due to the lack of a publicly available, geocoded dataset of historical OHCA cases, there is not a coherent approach for identifying priority areas for AEDs placement in this country. This study attempts to fill this gap by examining the spatial disparity of OHCA risk in Hangzhou, China, and then proposing a Geographic Information Systems(GIS) based model that incorporates the urban land cover, vulnerable groups, and transportation accessibility to identify priority areas at the hexagon level for future AEDs placement. Results show that: (1) the hexagons with the highest level of OHCA risk (ranked Group 1) are accounting for 9.87%–16.71% and are spatially dispersed. (2) A large high-risk cluster was identified in the western region of the Qiantang district. (3) Nearly one-fifth of the new AEDs are recommended to install in Phase I, more than 60% in Phase II, and the remainder in Phase III. (4) Xiaoshan district requires the most AEDs, while Linping district requires the fewest. Ultimately, these results guide future placement of the AED facilities in the cities, particularly those with no geocoded OHCA historical data.]]></description>
      <pubDate>Thu, 22 Jun 2023 09:49:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/2157481</guid>
    </item>
    <item>
      <title>Evaluation on the use of COVID-19 single-use face masks to improve the properties of hot mix asphalt</title>
      <link>https://trid.trb.org/View/2144243</link>
      <description><![CDATA[With the outbreak of the coronavirus (COVID-19) and the spread of this virus, the use of medical equipment, like 3-layerface masks, has increased dramatically. The proliferation of polymer-based face masks has become an environmental problem as it takes years to completely decompose. The lack of proper management and collection causes environmental pollution. Therefore, considering the polymer base of the face masks and with the aim of improving the asphalt mixtures, in this article, the face mask and its different layers are added to the asphalt mixtures in 4 different weight percentages and in two different sizes, and Marshall test, Resilient modulus, Indirect tensile, Moisture damage, Rutting and Fatigue test were performed on the samples. The experimental results show that the addition of these materials to the asphalt mixtures improves the performance of asphalt and 12mm long fibers yielded better results than the results of 8mm long fibers.]]></description>
      <pubDate>Wed, 31 May 2023 10:58:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/2144243</guid>
    </item>
    <item>
      <title>Design and analysis of a two-tier stretcher frame</title>
      <link>https://trid.trb.org/View/2145998</link>
      <description><![CDATA[In the current market, commercial aircraft carry stretchers in single tiers. This requires approximately three seat rows to be rendered unusable, which can be costly for airlines, resulting in fewer airlines providing the service. An alternative mode of transport for stretcher bound patients is to travel via air ambulances, which is not only costly, but with distance limitations. In this paper, a solution to this is explored by the introduction of a two-tier stretcher frame, capable of carrying two stretcher bound patients on a selected commercial aviation stretcher. Three conceptual designs are generated and modelled on solidworks. The stress analysis of the design is simulated via Abaqus CAE and validated with theoretical calculations. Furthermore, a design failure modes and effects analysis and cost analysis of the design are carried out. It is concluded that all the requirements identified for the design are met and it is fit for use on the aircraft.]]></description>
      <pubDate>Thu, 25 May 2023 17:41:09 GMT</pubDate>
      <guid>https://trid.trb.org/View/2145998</guid>
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