Long-distance Vehicles Research Articles

Online calibration method for SINS/LDV integrated navigation system based on left group error definition

The integration of strapdown inertial navigation system (SINS) and laser Doppler velocimeter (LDV) is a reliable technology for land vehicle positioning. To ensure the best positioning performance of the SINS/LDV integrated navigation system, it is necessary to calibrate it accurately. However, the accuracy of the error model of the traditional calibration method is seriously affected by the large misalignment angle, which in turn affects the accuracy and consistency of the filtering, and eventually leads to the decline of the calibration accuracy. Therefore, this paper introduces the Lie group theory for the first time into the calibration study of the SINS/LDV integrated navigation system. Based on the error state vector defined by the left group error definition in the Lie group, the three calibration models of the SINS/LDV integrated navigation system are derived in the Earth-centered Earth-fixed frame, using velocity, displacement increment, and dead reckoning (DR) position, which are the three common observation information. The most significant advantage of these calibration models is their ability to handle large initial misalignment angles. The calibration models proposed in this paper are comprehensively evaluated by two long-distance vehicle experiments. The test results show that under normal conditions (no large attitude misalignment angle and all sensors are working properly), the Lie group-based calibration methods have similar performance to the traditional calibration method, but they have significant advantages in the case of large initial attitude deviation. In addition, using displacement increment and DR position as observations improves calibration performance compared to velocity.

Multiple Aerial Videos-based Long-Distance Vehicle Trajectory Construction with Spatiotemporal Continuity

Multiple Aerial Videos-based Long-Distance Vehicle Trajectory Construction with Spatiotemporal Continuity

Use of passive data for determining link level long distance trips

Long-distance trips include a high value of time compared to short-distance trips; thus, capturing long-distance trips contributes to substantial economic and social benefits. This study utilizes privacy-protected travel data collected from mobile devices in Maryland to identify the link-level proportion of long-distance vehicle trips. We propose applying existing econometric frameworks, i.e., the generalized linear and beta regression models, to predict these link-level long-distance trips. Among the covariates, we utilize highway network-level attributes from the Maryland statewide travel demand model (MSTM), employment, and other open-source datasets available for the state of Maryland. Both the econometric models were compared for their performance in multiple measures like validation, behavioral interpretation, and goodness of fit. The best model results indicate a positive relationship between the proportion of long-distance trips and link attributes, like functional class, speed, and surrounding household density. The proposed framework will provide useful insights and key inputs for practitioners in demand modeling in capturing long-distance travel in a roadway network.

Research on vehicle detection based on improved YOLOX_S

Aiming at the problem of easy misdetection and omission of small targets of long-distance vehicles in detecting vehicles in traffic scenes, an improved YOLOX_S detection model is proposed. Firstly, the redundant part of the original YOLOX_S network structure is clipped using the model compression strategy, which improves the model inference speed while maintaining the detection accuracy; secondly, the Resunit_CA structure is constructed by incorporating the coordinate attention module in the residual structure, which reduces the loss of feature information and improves the attention to the small target features; thirdly, in order to obtain richer small target features, the PAFPN structure tail to add an adaptive feature fusion module, which improves the model detection accuracy; finally, the loss function is optimized in the decoupled head structure, and the Focal Loss loss function is used to alleviate the problem of uneven distribution of positive and negative samples. The experimental results show that compared with the original YOLOX_S model, the improved model proposed in this paper achieves an average detection accuracy of 77.19% on this experimental dataset. However, the detection speed decreases to 29.73 fps, which is still a large room for improvement in detection in real-time. According to the visualization experimental results, it can be seen that the improved model effectively alleviates the problems of small-target missed detection and multi-target occlusion.

Long-Distance Vehicle Dynamic Detection and Positioning Based on Gm-APD Lidar and LIDAR-YOLO

Aiming at the problems of long-distance night dynamic object detection in military operations, such as difficult imaging of traditional equipment, a small number of object pixels, a large difference in object size at different distances, and poor real-time performance. A long-distance vehicle detection method based on the LIDAR-YOLO network for Gm-APD (Geiger mode avalanche photodiode) lidar image is proposed. This method is improved based on YOLOv5s, which can detect long-distance vehicles and accurately locate motion trajectories in real-time. Firstly, the intensity image I of the lidar is preprocessed and combined with the distance image R, the BC_IIR image is obtained, and the vehicle detection data set is established. Then, according to the obvious vehicle features in the BC_IIR image, the low-complexity backbone network LIDARNet is redesigned, and several attention mechanism modules are added. The network feature extraction ability is enhanced by comparing and selecting the CA attention mechanism module. In the network prediction layer, context-aware feature map fusion is added to improve the detection precision of vehicles at different distances. Next, a GIOU loss is introduced to improve the detection precision of occluded vehicles. Finally, the method can depict the trajectory of the vehicle in 3D space based on distance information. After testing, the network achieves a detection speed of 62.67 frames per second (FPS), recall rate (R) = 98.19%, precision rate (P) = 95.53%, and F1 is 0.9675. The results show that the algorithm has better performance than other methods.

Analysis of Antenna Types on the Effect of GSM Module Signals as Remote Vehicle Safety

The National Police revealed that in 2018 there were 165,918 cases of crime in Indonesia, with 19,380 cases of theft due to the lack of additional safety in vehicles. Thus, remote vehicle safety is needed to turn off the vehicle in the event of an act of theft. However, this remote security is still difficult to work if the signal quality from the BTS is weak. Because it needs a signal amplifier in the GSM module. The purpose of this paper is to analyze the effect of the GSM module signal on the injector response time as an android-based long-distance vehicle safety. The signal booster is useful so that this long-distance vehicle safety can work properly when the signal quality from the BTS is weak. The research method used is the two-way Anova method. There are two independent variables, namely: (1) BTS signal quality; (2) the antenna material is copper and aluminum. The dependent variable uses the injector response time. The test results show that in testing the BTS signal quality, copper antennas have the fastest response time compared to aluminum antennas. -60 dBm is 4.402 second and -113 dBm is 5.472 second. The conclusion of this study is that copper antennas respond faster than aluminum antennas, because copper has a higher conductivity than aluminum. 
 Keywords: Vechicle Safety, GSM Module, Remote Vehicle Safety

An Analysis of Effect GSM Signal Type on Android-Based Vehicle Injector Response Time

The crime of motor vehicle theft is increasing, the automotive industry continues to develop security systems to reduce the number of thefts that occur in Indonesia through the development of sophisticated features. The addition of a global positioning system (GPS) feature on a vehicle is an alternative to supporting a security system by providing vehicle location information when theft occurs. GPS provides location information by providing microcontroller input data. GPS on the vehicle becomes very important because with the GPS module the vehicle can be found by knowing an accurate location. However, the addition of a GPS module is often difficult to find because the distance changes frequently and it takes a long time to find it. The purpose of this paper is to detect vehicle position accurately using GPS U-Blox NEO 6M and to analyze the effect of GSM signal type on the response time of long-distance vehicle injectors based on android. The research method is data analysis to make conclusions, namely the two-way factor quantitative experimental method. The independent variables used are (1) different signal types, and (2) the distance from the signal source to the gasoline engine injector response time. The conclusion obtained is that vehicle position detection using GPS U-Blox NEO 6M is accurate with the results of data analysis shifting 8.3113 meters and the interaction between distance and GSM signal types has no significant effect with the results of data analysis from the three types of Telkomsel GSM signals which are the fastest with a distance of 200 meters from the signal source with a response time of 4.956 seconds and the slowest is XL at a distance of 500 meters from the signal source with a response time of 8.5 seconds.
 Keywords: Android-Based Vehicle Injector, GSM Signal Type, Vehicle Injector

Lipidomics Analysis of Outer Membrane Vesicles and Elucidation of the Inositol Phosphoceramide Biosynthetic Pathway in Bacteroides thetaiotaomicron.

ABSTRACTApproximately one-third of the human colonic microbiome is formed by bacteria from the genus Bacteroides. These bacteria produce a large amount of uniformly sized outer membrane vesicles (OMVs), which are equipped with hydrolytic enzymes that play a role in the degradation of diet- and host-derived glycans. In this work, we characterize the lipid composition of membranes and OMVs from Bacteroides thetaiotaomicron VPI-5482. Liquid chromatography-mass spectrometry (LC-MS) analysis indicated that OMVs carry sphingolipids, glycerophospholipids, and serine-dipeptide lipids. Sphingolipid species represent more than 50% of the total lipid content of OMVs. The most abundant sphingolipids in OMVs are ethanolamine phosphoceramide (EPC) and inositol phosphoceramide (IPC). Bioinformatics analysis allowed the identification of the BT1522–1526 operon putatively involved in IPC synthesis. Mutagenesis studies revealed that BT1522–1526 is essential for the synthesis of phosphatidylinositol (PI) and IPC, confirming the role of this operon in the biosynthesis of IPC. BT1522–1526 mutant strains lacking IPC produced OMVs that were indistinguishable from the wild-type strain, indicating that IPC sphingolipid species are not involved in OMV biogenesis. Given the known role of sphingolipids in immunomodulation, we suggest that OMVs may act as long-distance vehicles for the delivery of sphingolipids in the human gut.IMPORTANCE Sphingolipids are essential membrane lipid components found in eukaryotes that are also involved in cell signaling processes. Although rare in bacteria, sphingolipids are produced by members of the phylum Bacteroidetes, human gut commensals. Here, we determined that OMVs carry sphingolipids and other lipids of known signaling function. Our results demonstrate that the BT1522–1526 operon is required for IPC biosynthesis in B. thetaiotaomicron.

Traffic incident detection based on a global trajectory spatiotemporal map

Traffic incidents endanger the smooth running of vehicles. Congestion caused by traffic incidents has caused a waste of time and fuel and seriously affected transportation efficiency. At present, most methods use manual judgment or image features to detect traffic incidents, but these methods lack timeliness, leading to secondary incidents. For dangerous road sections such as ramp-free and long downhills, this paper proposes an algorithm to quickly detect traffic incidents based on a spatiotemporal map of vehicle trajectories. First, a vehicle dataset from the monitoring perspective is constructed, and an improved YOLOv4 detection algorithm is used to detect images organized as batches. Based on the detection result, the multi-object tracking method of vehicle speed prediction in key frames is used to obtain the vehicle trajectory. Then according to the vehicle trajectory obtained in a single scene, the vehicle trajectory is reidentified and associated in the continuous monitoring scene to construct a long-distance vehicle trajectory spatiotemporal map. Finally, according to the distribution and generation status of the trajectory in the spatiotemporal map, traffic incidents such as vehicle parking, vehicle speeding, and vehicle congestion are analyzed. Experimental results show that the proposed method greatly increases the speed of vehicle detection and tracking and obtains high mAP, MOTA, and MOTP indicators. The global spatiotemporal map constructed by trajectory reidentification can achieve high detection rates for traffic incidents, reduce the average elapsed time, and avoid the problems of the inaccuracy of analyzing image features.

Feasibility assessment of hydrogen-rich syngas spark-ignition engine for heavy-duty long-distance vehicle application

The feasibility of syngas-fueled engine was assessed in numerical simulation using the single-cylinder engine experiment and on-road driving data. A 6-cylinder, 1841-cm3, spark-ignition engine was designed for a highway express bus in South Korea. Firstly, a one-dimensional engine model was constructed on a basis of the single-cylinder engine experimental data. The valve timings were optimized for maximizing the intake air flow at each engine speed. Then, the vehicle simulation model was built for the highway express bus equipped with the syngas engine and 10-speed automatic transmission. A parametric investigation was performed to optimize the gear shift schedule for the best fuel economy under on-road driving condition. The driving data was acquired from an actual highway express bus traveled from Daejeon to Seoul in South Korea. The syngas engine bus exhibited the trip fuel economy of 412 g/km in the driving simulation. The estimated travel distance was 194 km using the stock fuel tank employed for 20-MPa compressed natural gas.

RSU-Aided Remote V2V Message Dissemination Employing Secure Group Association for UAV-Assisted VANETs

Nowadays, the research on vehicular ad hoc networks (VANETs) remains a hot topic within the Internet of Things (IoT) scenarios. Diverse studies and techniques regarding all aspects of VANETs have been investigated thoroughly. Particularly, the wireless characteristic of heterogeneous vehicular communication, along with the complicated and dynamic connection topology among participating VANET entities, have severely affected the secure and stable data exchange. Specifically, the spontaneous vehicle-to-vehicle (V2V) message dissemination, as the essential functionality of VANET, plays a significant role for instant and real-time data sharing for vehicles within a certain vicinity. However, with the short-time interaction and high mobilization of vehicular connections, the remote V2V message delivery intended for long-distance vehicles in the range of different roadside units (RSUs) has not been properly researched. Meanwhile, both V2V and V2R (Vehicle-to-RSU) communication are highly restricted by environmental factors such as physical obstructions or signal interferences, thus drastically reducing the wireless connectivity in practical VANET implementations. In this case, the unmanned aerial vehicles (UAVs), as the auxiliary facilities, can provide the VANET with substitute wireless routes, so that the transmission quality and availability can be improved. In this paper, the authenticated UAV group association design is proposed at first. On this basis, the remote V2V message dissemination method is enabled, where the decentralized V2V connections involving all RSUs along the way are provided. The analysis regarding crucial security properties is presented accordingly, where the formal proofs and comparison are conducted. Moreover, the performance evaluation in terms of storage and time consumption during RSU authentication process is illustrated, respectively. Comparison results with the state-of-the-art prove that superiority on the major performance factors can be achieved.

Atmospheric and Turbocharged Experimental Investigation of Heavy Vehicle Compressor Air Inlet Line

Reciprocating compressors, which come from the past to the present and whose development is parallel to internal combustion engine technolo-gies, find themselves a large share in this field in line with the innovative studies on it. The stored compressed air demanded in the heavy vehicle segment, where almost all diesel engines are used, is serviced for two main tasks such as brake and suspension system. Therefore, the engine to be used during the compressor selection; efficiency, performance and service maintenance period are very important while meeting the de-mands and what applications are used such as long-distance vehicle, construction site vehicle, transport vehicle, garbage truck, coach.In this paper, experimental studies were carried out on a Scania brand diesel vehicle by feeding the air brake compressor from the engine tur-bocharger intercooler with an improved interconnection and convention-al atmospheric feeding. Temperature and pressure values obtained via sensors from the data collection system, performance information ob-tained from the vehicle CAN module and exhaust emission measurement results measured by opacimeter for both cases are presented.

Molecular Dynamics Characteristics and Model of Vehicle-Following Behavior

The vehicle-following behavior is a self-organizing behavior that restores dynamic balance under the stimulation of external environmental factors. In fact, there are asymmetric problems in the process of acceleration and deceleration of drivers. The existing traditional models ignored the differences between acceleration and deceleration of vehicles. In order to solve this problem, the vehicles driving on the road are compared to interacting molecules. Vehicle-following characteristics are studied, and the molecular following model is established based on molecular dynamics. The model parameters under different conditions are calibrated considering the required safety distance by the vehicle and the reaction time of the driver. With the help of the vehicle running track graphs, speed, and acceleration graphs, the numerical simulations of the molecular following model and the classical optimal speed vehicle-following model are carried out. The results of the comparative analysis show that the acceleration in the process of acceleration and deceleration is not constant but more sensitive to the deceleration of the preceding vehicle than to the acceleration and more sensitive to the acceleration/deceleration of the short-distance vehicle than to the acceleration/deceleration of the long-distance vehicle. Therefore, the molecular following model can better describe the vehicle-following behavior, and the research results can provide a theoretical basis and a technical reference for the analysis of traffic flow dynamic characteristics and adaptive cruise control technology.

Secretion of Salmonella Pathogenicity Island 1-Encoded Type III Secretion System Effectors by Outer Membrane Vesicles in Salmonella enterica Serovar Typhimurium.

Outer membrane vesicles (OMVs) are spherical membranous structures released by Gram-negative bacteria. Several bacterial pathogens utilize OMVs as vehicles for the delivery of virulence factors into host cells. Results of our previous study on proteomic analysis revealed that OMVs isolated from Salmonella enterica serovar Typhimurium had virulence effectors that are known to be translocated by Salmonella pathogenicity island 1 (SPI-1)-encoded type III secretion system (T3SS1) into the host cell. In the present study, immunoblot analysis confirmed the secretion of the six T3SS1 effector proteins, namely SipB and SipC (translocators of T3SS1), and SipA, SopA, SopB, and SopE2 (effectors translocated by T3SS1), by OMVs. Results of proteinase K treatment revealed the localization of these T3SS1 effector proteins on the outer surface of OMVs. SipC and SopE2 were secreted by OMVs independent of the three secretion systems T3SS1, T3SS2, and flagella, signifying OMVs to be an alternative delivery system to T3SSs. T3SS1 effectors SipA, SipC, and SopE2 were internalized into the cytoplasm of the host cell by OMVs independent of cellular Salmonella–host cell contact. In epithelial cells, addition of OMVs harboring T3SS1 effectors stimulated the production of F-actin, thereby complementing the attenuated invasion of ΔsopE2 into host cells. These results suggest that S. Typhimurium might exploit OMVs as a long-distance vehicle to deliver T3SS1 effectors into the cytoplasm of the host cell independent of bacteria–host cell interaction.

Microvesicles and intercellular communication in the context of parasitism

There is a rapidly growing body of evidence that production of microvesicles (MVs) is a universal feature of cellular life. MVs can incorporate microRNA (miRNA), mRNA, mtDNA, DNA and retrotransposons, camouflage viruses/viral components from immune surveillance, and transfer cargo between cells. These properties make MVs an essential player in intercellular communication. Increasing evidence supports the notion that MVs can also act as long-distance vehicles for RNA molecules and participate in metabolic synchronization and reprogramming eukaryotic cells including stem and germinal cells. MV ability to carry on DNA and their general distribution makes them attractive candidates for horizontal gene transfer, particularly between multi-cellular organisms and their parasites; this suggests important implications for the co-evolution of parasites and their hosts. In this review, we provide current understanding of the roles played by MVs in intracellular pathogens and parasitic infections. We also discuss the possible role of MVs in co-infection and host shifting.

Psychoactive Substance Use Among Long Distance Vehicle Drivers In Ilorin, Nigeria

Background Globally, the association between psychoative substance use and accidental injury or death has been acknowledged, with efforts being made to reduce accident rates in all means of transportation. While many studies have examined the use of psychoactive substances among many occupational groups, including drivers, not many has focused on substances use among long distance vehicle drivers. Aim We determined the prevalence, pattern and factors associated with the use of psychoactive substances among long distance vehicle (LDV) drivers in Ilorin, Nigeria. Method All consecutive consenting LDV drivers seen at the study period were interviewed using a modified, pilot-tested, semi-structed self-report questionnaire based on the World Health Organisation\'s guideliness for student\'s substance use survey. Result It was found that the most currently used psychoactive substances were mild stimulants (31.9%), cigrattes (30.4%), anabolic steroids (27.5%) and alcohol (15.9%). Except for cigrattes, the other substances were used mainly for instrumental purposes. Only about 50% of the respondents had ever attended a health talk on drug abuse. High level of religiousity was less likely to be associated with current use of mild stimulants and sedatives. Current use of sedatives was also significantly associated with poor mental health. Conclusion With only 50% exposure to drug abuse campaign among drivers, we suggest that more efforts should be made to enlighten LDV drivers on the dangers of substances use and abuse. Such campaigns should take advantage of religion and the strong influence of the Driver\'s Unions on member. These efforts, we hope, will go a long way in reducing loss of lives and properties on our roads. Though no significant association was found between current drug use and rate of accidents, we suggest a larger scope study be conducted to corroborate or refute this finding. Nigerian Journal of Psychiatry Vol. 5 (1) 2007: pp. 14-18