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In this study, the effects of heatwaves (HWs) on liquefied petroleum gas (LPG) leaks were analyzed using the Areal Locations of Hazardous Atmospheres (ALOHA) program. For this purpose, data from an accident at a gas station in the Eryaman District of Ankara in January 2024 were utilized. Approximately 40 m3 of LPG was released during the incident, but no explosion occurred. The accident was simulated using atmospheric data from the accident date in the ALOHA program. In the simulations, emissions of propane and butane—the primary components of LPG—were modeled separately. To simulate the LPG leak during a HW, a HW was first defined based on daily maximum temperature data. The threshold was set at the 90th percentile, and temperatures persisting for three or more consecutive days were classified as a HW. Using this definition, a four-day HW in Ankara in July 2024 was identified. The atmospheric conditions during this HW were input into the ALOHA program for simulation. The study compared the simulation results of the LPG leak in January with those during the HW period. The findings showed that the sub-explosion areas for propane and butane during the HW were 2% (95% CI: 0.91–1.15, p > 0.05) and 9% (95% CI: 0.84–1.42, p < 0.05) larger, respectively, than those during the accident in January. As a result, the study highlights the need for stricter safety measures during summer months when transporting explosive materials.
Öztürk, Yunus
The paper presents the results of investigations on the exhaust emissions carried out under real-world operating conditions of gasoline engines used in lawnmowers and power generators. During the operation of these engines, the authors measured the emissions of the following exhaust gaseous components: CO, HC, NOx, and CO2. For the measurements, the authors used Axion R/S+, a PEMS (Portable Exhaust Emission System) analyzer. The presented method is a new approach to exhaust emissions measurements performed on small engines. The emission coefficient, as a related value of the emission of harmful compounds and CO2, was proposed. Additionally, some remarks related to the measurement method were made. The paper presents the modal analysis of the investigations of the exhaust emissions from engines and the total mass of gaseous compounds. Moreover, the obtained results of the exhaust emissions from the power generator engine were compared with the applicable emission standards, and the real emissions of CO and HC+NOx were, respectively, about 10% and 38% higher than Stage II standards. Based on the investigation results, the authors considered the possibilities of using the said measurement method in real-world operating conditions, applying the PEMS equipment for small gasoline engines.
Lijewski, Piotr, Markiewicz, Filip, Fuć, Paweł, Dobrzyński, Michał, Wiśniewski, Sławomir
Bicycle computers and apps record, at minimum, positional data over time, and these data are commonly used in accident reconstruction to understand the behavior of the bicycle and rider prior to an incident in question. These positional data are obtained using the Global Positioning System (GPS), and while their absolute positional accuracy has been the subject of prior research, their accuracy at detecting and reporting particular movements is less studied. To improve the accident reconstruction industry’s understanding of these devices’ performance, this research aims to statistically quantify the temporal and positional accuracy of these devices reporting the onset of a lateral deviation or lane change. Controlled testing was performed and recorded with several commercially available bicycle GPS computers and apps, which were compared to a RaceLogic VBox 3i ADAS with Real-Time Kinematics (RTK) corrections from a RaceLogic Base Station. Three separate test bouts were performed, with each test bout consisting of 30 or 32 repeats of three different lateral deviation maneuvers. The bicycle GPS computers were individually synchronized to the RaceLogic data by offsetting their time to minimize the mean-square positional error across the entire test bout, which enabled calculation of the 50th percentile and 95th percentile absolute positional errors for each device. A custom script was then used to programmatically detect the start of each lateral deviation, and then, confidence intervals were calculated to estimate the probability of each GPS device reporting the start of the lateral deviation with zero lead or lag, with 1 s of lag, or with 0 or 1 s of lag based on the relative timestamps and positional data. All three of the tested bicycle GPS computers had a probability of at least 0.5 of reporting the onset of sharp lateral movements with zero lead or lag based on the time data, while only two of the devices maintained a similarly high probability for the position-based data. The iPhone 17 Pro had a probability greater than 0.6 of detecting the onset of both gradual and sharp lateral movements with 1 s of lag for both the time-based and position-based data. And across all lateral movement types, all devices had a probability of at least 0.6 of reporting the onset of lateral movement with either 0 or 1 s of lag.
Sweet, David Michael, Bretting, Gerald, Wilhelm, Chris, O’Brien, Nathan
The purpose of this document is to expressly describe the required diagnostics (DIAG) related to the on-road traction battery management systems (BMS). This document will attempt to clearly educate and explain four key areas of BMS DIAG: (1) fault identification, (2) fault classification, (3) system reaction, and (4) diagnostic data and reporting.
Battery Management Systems Committee
The purpose of this document is to expressly describe the method of calculating state of charge (SOC) related to the on-road traction battery management systems (BMS). This document will attempt to clearly educate and explain four key areas of BMS SOC: (1) basic SOC definition, (2) SOC calculation methods, (3) influence items for SOC, and (4) SOC warnings.
Battery Management Systems Committee
The purpose of this document is to expressly describe the method of calculating state of health (SOH) related to the on-road traction battery management systems (BMS). This document will attempt to clearly educate and explain four key areas of BMS SOH: (1) basic SOH definition, (2) SOH calculation methods, (3) influence items for SOH, and (4) SOH reporting.
Battery Management Systems Committee
This specification covers a fuel-resistant polythioether sealing compound with low specific gravity, supplied as a two-component system which cures at room temperature.
AMS G9 Aerospace Sealing Committee
This SAE Recommended Practice contains dimensions and their tolerances concerning disc wheel to hub or drum interface areas for truck and bus applications. Disc wheels designed only for single wheel applications (not dual wheels) for light trucks and special or less common applications are not covered in this document.
Truck and Bus Wheel Committee
SAE J3113 provides principles and a process for developing icons for use in electronic displays related to off-road work machines as stated defined in SAE J1116. Following the process ensures that icons are derived from ISO-registered graphical symbols or ISO-compliant non-registered graphical symbols.
HFTC2, Machine Displays and Symbols
This SAE Aerospace Standard (AS) specifies the characteristics of screw threads - UNJ profile, inch, series, including a mandatory controlled radius as specified in Table 1 at the root of the external thread. The minor diameter of both external and internal threads provides a basic thread height of .5625H to accommodate the external thread maximum root radius. The following detailed design requirements are included: Screw threads - UNJ basic profile and design profiles. Standard series of diameter-pitch combinations for nominal thread diameters from 0.060 to 6.000 inches. Standard thread classes and form tolerances. Formulae for thread dimensions and tolerances. Method of designating UNJ threads. Tables for selected diameter-pitch combinations for close tolerance mechanical thread applications. Tables for screw thread - UNJ profile thread limit dimensions.
E-25 General Standards for Aerospace and Propulsion Systems
This specification contains requirements for, and applies to, commercial and military aircraft external/ground electrical power cable assemblies, using either overmolded or attachable plug connectors used to connect external/ground electrical power to aircraft and to attachable plugs used as replacements for plugs damaged in service.
AE-8A Elec Wiring and Fiber Optic Interconnect Sys Install
This SAE Aerospace Standard (AS) establishes guidelines for enhancement to IEEE 1394-2008 Beta (formerly IEEE 1394b) PHYsical (PHY) layer. It encompasses enhancements to the IEEE 1394-2008 Beta PHY to reduce port connection times and increase port connection reliability. Therefore, this document contains extensions/restrictions to “off-the-shelf” IEEE 1394 standards and assumes that the reader already has a working knowledge of IEEE 1394. The enhancements covered in this document include: Detect loss of descrambler synchronization Fast-ReTrain (FRT) Fast Power-on Re-connect (FPR) Fast Connection Tone Debounce (FTD) Programmable invalidCount Bus Reset Cause This document does not identify specific environmental requirements (electromagnetic compatibility, temperature, vibration, etc.); such requirements will be vehicle-specific and even LRU-specific. One should refer to the appropriate sections of MIL-STD-461E for their particular LRU and utilize handbooks such as MIL-HDBK-454A and MIL-HDBK-5400 for guidance. This document is referred to as a “slash sheet” and accompanies the AS5643B base standard.
AS-1A Avionic Networks Committee
G-3, Aerospace Couplings, Fittings, Hose, Tubing Assemblies
This SAE Aerospace Recommended Practice (ARP) addresses aeronautical Propulsion System Health Management. Aircraft propulsion systems are broader than gas turbine engines and include electric and hybrid propulsion systems. Furthermore, health management of auxiliary systems such as for thermal management of electric propulsion modules is also included in the scope. This document uses the term Engine Health Management (EHM) to include health management of propulsion systems and related equipment such as electric motors and heat exchangers for thermal management in an integrated power and propulsion system (IPPS). This keystone document gives a top-level view and addresses EHM description, benefits, and capabilities, and provides examples. This ARP purposely addresses a wide range of EHM architectures to demonstrate possible EHM design options. This ARP is not intended as a legal document and does not provide detailed implementation steps but does address potential benefits and general implementation issues. Other SAE documents (aerospace standards, aerospace recommended practices, and aerospace information reports) address specific component specifications, procedures, and “lessons learned.”
E-32 Aerospace Propulsion Systems Health Management
This specification covers a corrosion-resistant steel in the form of bars, wire, forgings, and forging stock.
AMS F Corrosion and Heat Resistant Alloys Committee
This specification covers a corrosion-resistant steel in the form of plate up to 3.00 inches (76.2 mm), inclusive, in nominal thickness.
AMS F Corrosion and Heat Resistant Alloys Committee
This specification covers an aluminum alloy in the form of sheet and plate up to 2.000 inches (50.80 mm), inclusive, in thickness. (see 8.5)
AMS D Nonferrous Alloys Committee
This document recommends criteria for the layout and for the design, installation, and operation of flight deck facilities for transport aircraft.
S-7 Flight Deck Handling Qualities Stds for Trans Aircraft
This specification covers a premium aircraft-quality steel in the form of bars, forgings, mechanical tubing, flash-welded rings up through 10.000 inches (254.00 mm), inclusive, in diameter or least distance between parallel sides, and stock of any size for forging or flash-welded rings.
AMS E Carbon and Low Alloy Steels Committee