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Autonomous truck platoons hold the potential for substantial economic and environmental advantages. However, there is a lack of comprehensive research on the interactions between drivers and different configurations of truck platoons at waving segments. This study aims to contribute to the literature by achieving three primary objectives: (1) examine the effects of various truck platoon configurations on merging and diverging behaviors [time to merge (TTM) and time to diverge (TTD)]; (2) explore the impact of individual characteristics such as age, gender, education level, and driving experience on TTM and TTD; and (3) investigate the decision-making associated with these maneuvers (merging or diverging in front of the platoon, behind the platoon or cut in through the platoon). A driving simulator study was conducted with 85 participants across 12 distinct scenarios, considering variations in platoon size, intraplatoon spacing, and platoon lane-change behavior. Several statistical methods were employed, including ANOVA, the Cox proportional hazards model, and machine-learning techniques, to analyze the factors impacting TTM and TTD. The results revealed that increasing the headway distances between trucks in a platoon to 13.72 m (45 ft) or 18.29 m (60 ft) substantially decreased TTM, enhancing traffic flow. Furthermore, splitting the truck platoon between two lanes of the freeway before the merging point significantly influenced other drivers' merging decisions. When half of the trucks in a platoon switched to the left lane before the merging point, a larger proportion of participants chose to merge ahead of the platoon. Age, gender, education level, and self-assessment of driving skills were all found to significantly influence merging and diverging behaviors. Drivers with higher degrees took longer to merge, whereas older, male, and experienced drivers merged faster. The lowest average TTD was observed when half the platoon switched to the left lane before the diverging point. [ABSTRACT FROM AUTHOR]

Lack of visibility is one of the challenges that impact drivers' ability to perform driving tasks at night. Although prior studies indicated that lighting increases nighttime safety, lighting at stop-controlled intersections is not mandatory according to many U.S. states' guidelines. This paper aims to investigate the impact of different lighting conditions on safety-related driving behavior during nighttime at stop-controlled intersections. The data were collected using a driving simulator experiment where participants drove through several intersections during daytime, nighttime without lighting, nighttime with partial lighting, and nighttime with full lighting. Collected measures included speed, time-to-collision (TTC), and post-encroachment time (PET). TTC/PET were used as safety surrogate measures to evaluate the impact of lighting on drivers' safety. The results indicated that TTC/PET were higher during daytime and nighttime with partial/full lighting. Furthermore, the findings revealed that lower speeds were recorded at nighttime with partial/full lighting. Kruskal–Wallis test revealed that TTC/PET medians for nighttime without lighting were statistically significantly different from TTC/PET medians of the remaining lighting conditions. Moreover, negative binomial modeling indicated that lack of lighting and speed had inverse correlation with TTC. In summary, the results revealed that street lighting at stop-controlled intersections provided 37% increase in TTC, 15% increase in PET, and 15% reduction in speed. [ABSTRACT FROM AUTHOR]

A multiparameter analysis was conducted to evaluate the impact of meteorological parameters, night sky brightness and seismic hazards on proposed sites for the new optical/infrared Egyptian astronomical telescope. The European Centre for Medium-Range Weather Forecasts (ECMWF) Reanalysis v5 (ERA5) data set is used to obtain the following meteorological parameters: total cloud coverage fraction, precipitable water vapour, relative humidity, wind speed and direction, and air temperature. To estimate the aerosol optical depth, we used the Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA-2). Light pollution over the candidate sites was measured using the Visible Infrared Imaging Radiometer Suite (VIIRS) day/night band. In order to assess the seismic hazards for the candidate sites, the seismic input in terms of maximum acceleration and response spectra was computed using a physics-based ground motion approach to assess the seismic hazards and, consequently, the designation of a seismic-resistant structure for the proposed sites. Of the seven nominated sites, two sites are found to have the best measurements and might be considered as future sites for the new Egyptian astronomical telescope. The first site is located in the south of the Sinai peninsula, while the second site is located in the Red Sea mountains region. [ABSTRACT FROM AUTHOR]

Introduction: Masonry minarets in Old Cairo are highly susceptible to earthquake damage, particularly those not designed or updated to withstand seismic loads. Therefore, regular monitoring is necessary to ensure their safety and detect any deterioration or reduction in seismic performance. The direct loss of a minaret can lead to the collapse or severe damage to the structure itself. The cascading impacts of partial or complete minaret failure can have significant consequences for the immediate vicinity and the broader community. By studying the effects of earthquakes on minarets and developing mitigation strategies, countries can take proactive measures to protect these structures and ensure the safety of people. Objective: This study focuses on a specific type of Islamic architecture: the historic minarets in Cairo. The research aims to evaluate the seismic vulnerability of eight cultural heritage minarets in Cairo, identifying the parameters influencing their seismic behaviour and susceptibility to earthquake damage. Methods: The research utilizes empirical seismic vulnerability methods and ambient vibration measurements on eight minarets. An empirical approach compatible with the nature and style of the minarets is employed to evaluate their vulnerability using index values and curves. The method's validity is assessed, and areas of conformity and limitations are identified. Ambient vibration tests (AVTs) are also conducted using a temporary seismic network installed at various heights inside each minaret to determine their dynamic characteristics. Results: The seismic vulnerability Index (I_V) is calculated for the selected minarets based on the state of each vulnerability parameter. The contribution of each parameter to the final I_V values of the minarets are presented. Vulnerability curves are developed for each minaret, interpreting the conventional vulnerability indexes in terms of mean damage grades for seismic events with varying intensity on the EMS-98 scale. These mean damage grades can also indicate the expected damage levels of structural and non-structural minaret elements for events with different seismic intensity levels. AVTs are conducted at various heights on the selected minarets, and the dynamic characteristics are extracted from the recorded data. Variations in these characteristics are considered significant for structural health monitoring analysis. The peak-picking method is employed to directly extract each minaret's natural frequencies and mode shapes, as changes in dynamic characteristics are relevant to health monitoring analyses. Conclusions: The recent study examined the seismic vulnerability assessment of eight masonry minarets in the historic Old Cairo district. The assessment revealed vulnerability index values ranging from 10.3 to 26.1, indicating a concerning susceptibility to seismic events among these structures. Vulnerability curves were constructed for each minaret, visually representing potential damage scenarios across different levels of the EMS-98 intensity scale. These outcomes are significant as they facilitate prioritizing interventions to safeguard the most vulnerable minarets. Additionally, a novel empirical period equation was introduced to estimate the fundamental period of minarets in Old Cairo based on their heights. The equation was validated against field measurements and data from the literature. The study is limited by its focus on a specific category of minarets, specifically the historical masonry minarets in Old Cairo. Furthermore, limitations arise from the need for detailed finite element models to capture these minarets' dynamic responses accurately. Therefore, ongoing research involves the development of detailed finite element models and calibrating fundamental periods for the selected minarets. The anticipated results hold the potential to enhance our understanding of the structural dynamics of historical minarets, ultimately guiding the formulation of tailored seismic retrofitting and preservation strategies. These strategies, aimed at preserving these cherished cultural heritage assets, represent our collective commitment to ensure the endurance of these timeless landmarks for future generations. [ABSTRACT FROM AUTHOR]

In this research, we have compiled a catalogue of the worst tsunami earthquakes that caused destruction and losses in the northern coastal region of Egypt. Variability in seismic source parameters reflects the level of cognitive uncertainty that exists because most of these destructive tsunamis, if not all, occurred in the pre-instrumental period. We also synthesized a set of hypothetical tsunamis constrained by seismotectonic knowledge of the area of influence to embrace the uncertainty. We also collected the topo-bathymetry information available to make a simulation on the scale of the Egyptian north coast. The multiple scenarios were computed considering references and hypothetical scenarios, and results were presented in maps and tables for wave heights, inundation depth, and estimated arrivals. Comparisons were made between the results calculated in this study and those from previous studies. These were done to identify and measure the reasons for the difference and similarities. The results may contribute to developing risk reduction strategies and a national early warning system. Variability in tsunami intensity measures is prepared for the hypothetical scenarios due to the difference in the fault's magnitude, location, and geometry. Also, for the first time, temporally based scenarios the sea-level rise and delta sinking were considered in order to highlight the importance of multi-risk analysis for the region of interest. The insight on incorporating other hazards of the temporal resolution indicates a significant increase in inundated areas and wave height. Therefore, proper and detailed estimation of multi-hazard maps for the coastal region of the Nile Delta is highly required to protect the ongoing sustainable development and protect the people and their assets. [ABSTRACT FROM AUTHOR]

In this research, we have compiled a catalogue of the worst tsunami earthquakes that caused destruction and losses in the northern coastal region of Egypt. Variability in seismic source parameters reflects the level of cognitive uncertainty that exists because most of these destructive tsunamis, if not all, occurred in the pre-instrumental period. We also synthesized a set of hypothetical tsunamis constrained by seismotectonic knowledge of the area of influence to embrace the uncertainty. We also collected the topo-bathymetry information available to make a simulation on the scale of the Egyptian north coast. The multiple scenarios were computed considering references and hypothetical scenarios, and results were presented in maps and tables for wave heights, inundation depth, and estimated arrivals. Comparisons were made between the results calculated in this study and those from previous studies. These were done to identify and measure the reasons for the difference and similarities. The results may contribute to developing risk reduction strategies and a national early warning system. Variability in tsunami intensity measures is prepared for the hypothetical scenarios due to the difference in the fault's magnitude, location, and geometry. Also, for the first time, temporally based scenarios the sea-level rise and delta sinking were considered in order to highlight the importance of multi-risk analysis for the region of interest. The insight on incorporating other hazards of the temporal resolution indicates a significant increase in inundated areas and wave height. Therefore, proper and detailed estimation of multi-hazard maps for the coastal region of the Nile Delta is highly required to protect the ongoing sustainable development and protect the people and their assets. [ABSTRACT FROM AUTHOR]

Copyright of Egyptian Journal of Botany is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, we outline the overview of the problem of intraplate seismicity and summarize our studies aimed at identifying potential earthquake sources in three regions located in continental environments. We study the French Massif Central situated within the West-European platform, the Gujarat area located at the northwestern edge of the Indian shield, and northeast Egypt located in the northeastern part of the African continent. These regions exhibit different levels of seismic activity. The French Massif Central reveals the lowest rate of seismicity, northeast Egypt exposes a low-to-moderate seismicity, and Gujarat reveals moderate seismicity with rare occurrence of strong events. We use a phenomenological approach for identifying possible locations of earthquakes, which is based on the pattern recognition applied to morphostructural data. The approach hypothesizes the nucleation of strong earthquakes at morphostructural nodes forming at the intersections of morphostructural lineaments, which are delineated by morphostructural zoning. Nodes are characterized by the pertinent geophysical and geological parameters, on the basis of which pattern recognition algorithm pinpoints capable nodes, i.e., the nodes where events of a certain sizes may occur. Seismic hazard assessment of continental regions is impeded because their seismic history is normally very pure. In such a situation, information on capable nodes is a necessary input for seismic hazard assessment. The example of northeast Egypt shows the exploiting capable nodes to assess seismic hazard by the Neo-Deterministic Seismic Hazard Assessment Methodology. [ABSTRACT FROM AUTHOR]

On 7th of August 2020, a Mw = 4.9 earthquake occurred in Mila province (Northeast Algeria). Consequently, more than 2000 houses were indirectly affected (partially damaged or collapsed) within 10 km from the earthquake's epicenter, in the locality of El Kherba. According to field surveys conducted 3 days after the earthquake, damages and casualties were directly linked to an earthquake-induced landslide that occurred after the main shock. This was evidenced by numerous cracks in the site's soil mainly perpendicular to the landslide direction. Local characteristics (i.e., geology, geomorphology) and anthropogenic activities expose this area to landslide hazard. This study shows the reliability of the ambient noise horizontal to vertical spectral ratio (HVSR) method in the characterization of an active landslide. Ambient noise records were processed through spectral ratio techniques to identify the landslide's geometry based on spectral responses analysis. The obtained results allowed the landslide's slip surface mapping and boundary delineation, which correlates well with the field observations. After the rotation of the signal's horizontal components, large variations in the experimental spectral ratios, in both amplitude and direction, revealed site effects (soil remoulding, crack network) on the soil dynamic behavior. [ABSTRACT FROM AUTHOR]

Fish semen cryopreservation is a valuable technique to sustain good quality sperm for fertilization, facilitating threatened species conservation and broodstock genetic development. The present investigation aimed to develop suitable standardized protocols to cryopreserve sea bass (Dicentrarchus labrax) semen. Thus, four experiments were conducted to determine the most effective extender (egg-yolk citrate, urea-egg-yolk, and 0.9% NaCl), cryoprotectant (DMSO, glycerol, ethylene glycol "EG", and methanol), sperm/cryodiluent dilution ratio (1:2, 1:4, 1:10, and 1:20) and equilibration time (0, 5, 15, or 30 min) to maintain the sperm content after cryopreservation. The consistency of post-thaw semen was assessed, with motility percentage, motility duration, and fertilization rate all being taken into account. When sperms were thawed, the consistency was at its best, especially when sperm was diluted with a ratio of 1:20 with egg-yolk citrate extender containing 10% DMSO, with a 15-min equilibration period before cryopreservation. Sea bass sperm cryopreserved using this protocol exhibited fertilisation rates, class motility, and motility duration close to fresh semen. Thus, the cryopreservation method developed in the present investigation proved to be an efficient and effective approach to augment the cryosurvival of sea bass spermatozoa. [ABSTRACT FROM AUTHOR]

Pasteurella (P.) multocida and Mannheimia (M.) haemolytica are the most two common pathogenic bacterial agents causing pneumonia in calves. Both bacteria are associated with significant economic losses in the cattle industry due to high morbidity and mortality rates, especially in the case of severe infections. The objectives of the present study were to perform serotyping and genotyping, as well as characterization of the virulence-associated genes in 48 bacterial isolates; 33 P. multocida and 15 M. haemolytica. All strains were isolated from pneumonic cattle calves showing respiratory manifestations such as fever, nasal discharges, and rapid breathing in North Upper Egypt governorates (Beni-Suef and El-Fayoum). PCR was applied as a confirmatory test using a specific universal gene, kmt1, and rpt2 for P. multocida and M. haemolytica, respectively. The results show that 29 (87.9%) P. multocida and 15 (100%) M. haemolytica isolates were positive for the corresponding universal gene. The results of serotyping indicate that 86.2% of P. multocida isolates belonged to serotype B:2, while 13.8% were untyped. Meanwhile, 60% and 40% of M. haemolytica isolates belonged to serotype 2 and serotype 1, respectively. Investigation of virulence-associated genes showed that all the tested P. multocida isolates harbored nanB, omp87, and toxA genes. Four M. haemolytica isolates harbored both gcp and lktC genes and of these, three isolates harbored the ssa gene. Sequencing of toxA gene of P. multocida and lktC gene of M. haemolytica in the current strains indicated a great homology with strains uploaded in gene banks from different hosts and localities worldwide. [ABSTRACT FROM AUTHOR]

Seismogenic nodes capable of generating shallow earthquakes with M ≥ 5.0 have been identified in the northeast part of Egypt using the pattern recognition approach. The study region includes the Sinai Peninsula and the northern part of the Eastern Desert between the Nile River and the Red Sea, which comprises the new capital of Egypt and Suez Canal projects and represents a place for much future development. We apply a phenomenological approach based on pattern recognition for identifying seismogenic nodes. The methodology is based on the idea that earthquakes nucleate at nodes: specific structures forming around fault intersections. Morphostructural zoning (MZ) is applied to map nodes over the entire study region without using a priori knowledge of regional seismicity. The pattern recognition is employed to pinpoint seismogenic nodes where earthquakes with M ≥ 5.0 may occur in the future. As a result, seismogenic nodes capable of generating earthquakes with M ≥ 5.0 have been defined in the Sinai Peninsula and the northern part of the Eastern Desert. We also found characteristic geological-geophysical features that discriminate seismogenic nodes (D) from non-seismogenic ones (N). Information on the potential seismic sources represents the main issue in seismic hazard evaluation. Seismogenic nodes prone to earthquakes with M ≥ 5.0, as described in this work, may contribute to the definition of earthquake source zones in the northeast of Egypt because some of the D nodes are potential sources of seismic risk for critical facilities (e.g., Ismailia Tunnels) and large metropolitan areas (e.g., Nile Valley). This information can contribute to the revision of seismic zoning or microzoning and improve the performance of seismic hazard studies of Egypt by adding a new source of information about seismogenic nodes to the seismogenic zones. [ABSTRACT FROM AUTHOR]

Many crashes occur every year that involve drivers who are unlicensed and underage. One of the main challenges for traffic safety authorities is the lack of detailed information about this alarming phenomenon. This study aims to investigate the rate of underage driving among high school teenagers and thoroughly examine their awareness, perception, and use of the seat belt as one of the main in-vehicle safety features. Data was obtained from a self-report questionnaire. The results indicated that 59% of the participants drive without having a driver's license, and 47% reported that they use seat belts as a driver or a passenger. The results of the logistic regression model indicated that four significant factors affected high school teenagers' use of seat belts: (1) driving a car to school or “being a driver,” (2) personal perception of the role of seat belts in saving lives, (3) keen to require back-seat passengers to buckle up, and (4) previous attendance in a safety campaign that emphasized the importance of using seat belts. [ABSTRACT FROM PUBLISHER]

Numerous studies have demonstrated that the human factor is the main contributing factor leading to traffic accidents, followed by vehicle and road factors. In addition, many earlier studies have indicated that young drivers are at a high risk of being killed in traffic accidents around the world. Compared to other age groups, young drivers tend to be over-represented in severe and fatal crashes considering their percentage of the population. One way to improve traffic safety on highways is to improve the driving behavior of drivers, especially teenager drivers. There is a lack of studies that strived to thoroughly examine the driving behavior of young drivers in the Kingdom of Saudi Arabia (KSA). Thus, this study aims at identifying and quantifying the significant factors associated with the involvement of young Saudi drivers in at-fault crashes. Another objective of this study is to provide in-depth insights concerning the types of traffic violations that young Saudi drivers commit while driving and the main reason(s) that they are involved in risky driving behaviors. The data used for the analyses were obtained from a self-reported questionnaire survey carried out among 242 young drivers in Riyadh, the capital of the KSA. To achieve these goals, the structural equation modeling (SEM) approach was adopted using SAS software package. The results indicated that exceeding the speed limit was the main reason for obtaining traffic citations by young Saudi drivers (stated by approximately 73% of participants). Additionally, running late was the main reason for being involved in risky driving behaviors while driving (62%), followed by testing the performance of the car or showing off (18%). Moreover, the results of the SEM model indicated that aggressive violations (pressing the brakes and gas pedal at the same time while driving) was the most significant factor affecting young Saudi drivers' involvement in at-fault crashes between ages 18 and 24, followed by ordinary violations (i.e., driving so close to the car in front that it would be difficult to stop in an emergency) and attitudes toward speeding. Practical suggestions on how to improve the driving behavior of young Saudi drivers and how to reduce their crash risk, along with recommendations for future studies, are also discussed. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article investigates the factors affecting drivers' stated behavior in adverse visibility conditions and examines whether drivers rely on and follow advisory or warning messages displayed on portable changeable message signs (CMS) and/or variable speed limit (VSL) signs in different visibility and traffic conditions, and on two types of roadways: freeways and two-lane roads. A multiple-approach survey was designed to collect opinions and stated data from Central Florida drivers. Categorical data analysis techniques such as conditional distribution, odds ratio, and chi-squared tests were applied. In addition, two modeling approaches, bivariate and multivariate probit models, were estimated. The results revealed that gender, age, road type, visibility condition, and familiarity with VSL sign were the significant factors affecting the stated likelihood of reducing speed following CMS/VSL instructions in reduced visibility conditions. Other objectives of this study were to determine the content of messages that would achieve the best-perceived safety and drivers' compliance and to examine the best way to improve safety during these adverse visibility conditions. The results indicated that respondents thought that "Caution--fog ahead--reduce speed" was the best message and that using that CMS and VSL signs together was the best way to improve safety during such inclement weather situations. Based on the findings of the present study, several recommendations are suggested as guidelines to improve safety in reduced visibility conditions. [ABSTRACT FROM AUTHOR]