Safe Passage Research Articles

Timing is everything; operational changes at a pumping station with a gravity sluice to provide safe downstream passage for silver European eels and deliver considerable financial savings

Catadromous European eel (Anguilla anguilla) are a critically endangered fish species due in part to in-river anthropogenic barriers (e.g., pumping stations, weirs, hydropower facilities). European legislation stipulates that safe downstream passage must be provided at hazardous intakes. Where present, gravity sluices have the potential to act as safe and low-cost downstream passage for seaward migrating silver eels at pumping station, but operational changes are required. This study used catchment-wide and fine-scale acoustic telemetry to investigate if operational changes (OC) at a pumping station (PS) with a co-located gravity sluice (GS) facilitated safe downstream passage for silver European eels. Specifically, night-time pump operations were ceased, river levels prior to sluicing were elevated and the GS was opened during key eel migration windows, i.e., at night during the new moon phase in autumn. No tagged eels passed through any pumps and the majority (2018 = 87.5%, 2020 = 88.9%) that approached the PS during OC passed downstream through the GS. Most eels approached during the first period of night sluicing after release (2018 = 73.9% and 2020 = 76.5%) and passed downstream during the first sluice event they experienced at the PS (2018 = 66.7% and 2020 = 75.0%). During the final approach prior to passage, very few retreats back upstream occurred at a median (IQR) distance of 34 (7.25) m from the GS and were predominantly a short distance (1–8 m). Overall, OC at a PS with a GS are considered a win-win-win, despite opening the sluice for <3% of the study period, given safe downstream passage was maximised, the financial benefits of sluicing water (∼£14,670 in direct operational costs over two years) and the relative ease of implementation.

Nocturnal selective pressures on the evolution of human musicality as a missing piece of the adaptationist puzzle.

Human musicality exhibits the necessary hallmarks for biological adaptations. Evolutionary explanations focus on recurrent adaptive problems that human musicality possibly solved in ancestral environments, such as mate selection and competition, social bonding/cohesion and social grooming, perceptual and motor skill development, conflict reduction, safe time-passing, transgenerational communication, mood regulation and synchronization, and credible signaling of coalition and territorial/predator defense. Although not mutually exclusive, these different hypotheses are still not conceptually integrated nor clearly derived from independent principles. I propose The Nocturnal Evolution of Human Musicality and Performativity Theory in which the night-time is the missing piece of the adaptationist puzzle of human musicality and performing arts. The expansion of nocturnal activities throughout human evolution, which is tied to tree-to-ground sleep transition and habitual use of fire, might help (i) explain the evolution of musicality from independent principles, (ii) explain various seemingly unrelated music features and functions, and (iii) integrate many ancestral adaptive values proposed. The expansion into the nocturnal niche posed recurrent ancestral adaptive challenges/opportunities: lack of luminosity, regrouping to cook before sleep, imminent dangerousness, low temperatures, peak tiredness, and concealment of identity. These crucial night-time features might have selected evening-oriented individuals who were prone to acoustic communication, more alert and imaginative, gregarious, risk-taking and novelty-seeking, prone to anxiety modulation, hedonistic, promiscuous, and disinhibited. Those night-time selected dispositions may have converged and enhanced protomusicality into human musicality by facilitating it to assume many survival- and reproduction-enhancing roles (social cohesion and coordination, signaling of coalitions, territorial defense, antipredatorial defense, knowledge transference, safe passage of time, children lullabies, and sexual selection) that are correspondent to the co-occurring night-time adaptive challenges/opportunities. The nocturnal dynamic may help explain musical features (sound, loudness, repetitiveness, call and response, song, elaboration/virtuosity, and duetting/chorusing). Across vertebrates, acoustic communication mostly occurs in nocturnal species. The eveningness chronotype is common among musicians and composers. Adolescents, who are the most evening-oriented humans, enjoy more music. Contemporary tribal nocturnal activities around the campfire involve eating, singing/dancing, storytelling, and rituals. I discuss the nocturnal integration of musicality's many roles and conclude that musicality is probably a multifunctional mental adaptation that evolved along with the night-time adaptive landscape.

Innovations in Micropile Testing Using Distributed Optical Fibre Sensors

Micropiles are primarily used in situations where traditional foundation methods, such as large-diameter bored piles or driven piles, are not feasible due to various constraints, including limited access, low headroom, or the need to work in environmentally sensitive areas. They are often employed in urban areas with restricted space or for underpinning existing structures. Two case studies of instrumented micropiles are presented in this paper, with the aim to showcase innovations in pile testing using Distributed Optical Fibre Sensing (DOFS). In the first project, micropiles were installed as part of an underpinning work where several existing piles were removed to allow safe passage of Tunnel Boring Machine (TBM) underneath the building. An experiment pile was instrumented with conventional and DOFS sensors to measure pile responses due to tunnelling in proximity. In the second project, the micropile was tested to determine its load carrying capacity for buildings constructed in hilly area. In both cases, API pipes were applied and socketed into bedrocks. Optical cables were attached on four sides of the steel pipes and subsequently grouted. During the load tests, DOFS data were able to display precisely the shaft distribution of micropiles when subjected to vertical loads as well as bending behaviour due to the close proximity tunnelling. Interpretations of distributed strain profiles from DOFS have contributed to a better understanding of API-reinforced micropile performance under complex geological and loading conditions.

EP15.03: Alcohol exposure before and during pregnancy is associated with reduced fetal growth: the Safe Passage Study

EP15.03: Alcohol exposure before and during pregnancy is associated with reduced fetal growth: the Safe Passage Study

Move it or lose it: Predicted effects of culverts and population density on Mojave desert tortoise (Gopherus agassizii) connectivity.

Roadways and railways can reduce wildlife movements across landscapes, negatively impacting population connectivity. Connectivity may be improved by structures that allow safe passage across linear barriers, but connectivity could be adversely influenced by low population densities. The Mojave desert tortoise is threatened by habitat loss, fragmentation, and population declines. The tortoise continues to decline as disturbance increases across the Mojave Desert in the southwestern United States. While underground crossing structures, like hydrological culverts, have begun receiving attention, population density has not been considered in tortoise connectivity. Our work asks a novel question: How do culverts and population density affect connectivity and potentially drive genetic and demographic patterns? To explore the role of culverts and population density, we used agent-based spatially explicit forward-in-time simulations of gene flow. We constructed resistance surfaces with a range of barriers to movement and representative of tortoise habitat with anthropogenic disturbance. We predicted connectivity under variable population densities. Simulations were run for 200 non-overlapping generations (3400 years) with 30 replicates using 20 microsatellite loci. We evaluated population genetic structure and diversity and found that culverts would not entirely negate the effects of linear barriers, but gene flow improved. Our results also indicated that density is important for connectivity. Low densities resulted in declines regardless of the landscape barrier scenario (> 75% population census size, > 97% effective population size). Results from our simulation using current anthropogenic disturbance predicted decreased population connectivity over time. Genetic and demographic effects were detectable within five generations (85 years) following disturbance with estimated losses in effective population size of 69%. The pronounced declines in effective population size indicate this could be a useful monitoring metric. We suggest management strategies that improve connectivity, such as roadside fencing tied to culverts, conservation areas in a connected network, and development restricted to disturbed areas.

P-VERSE: Prioritization of Vehicles to Enhance Road Safety in IoT Environment

In this paper, we propose a scheme, named P-VERSE, to prioritize the emergency vehicles in the absence of a traffic signal at a multiway intersection point on a road. We consider the emergency vehicles, such as ambulance, fire trucks, or police vehicles, as prioritized vehicles and provide them safe and quick passage. The traffic signal is a traditional approach to minimize congestion, avoid collision among the vehicles, and reduce accidents. However, this results in the repetitive interruption of vehicles, thereby increasing their waiting time. To address these issues, we formulate a scheme that executes in two stages. In the first stage, we use Markov Chain to predict the future path of each vehicular nodes. Based on the predicted path, the common and emergency vehicles cooperatively form groups to avoid collision and congestion at the intersection point. On the other hand, in the second stage, we apply a cooperative coalition-based game-theoretic approach to design the strategic interactions among the vehicular nodes. These vehicular nodes act as players and dynamically form coalitions among them. Depending upon the utility of the coalition, the vehicular nodes either merge with or split out from a coalition. These nodes form a coalition to provide safe passage to the emergency vehicles. Further, we constrain our optimization problem to the Karush-Kuhn-Tucker (KKT) conditions and compute the optimal distance between the vehicular nodes. Extensive simulation-based analysis of our proposed scheme, P-VERSE, demonstrates that the energy consumption is reduced and utility is improved by 31.37% and 42.28% compared to the existing schemes proposed by Das et al. [1] and Xie et al. [2].

Timing co-evolutionary path optimisation method for emergency vehicles considering the safe passage

Emergency vehicles encounter traffic accidents at intersections of the network frequently, which seriously threatens the lives of rescue teams and patients. To improve the driving safety and travel efficiency of emergency vehicles, this study proposes a new method of timing co-evolutionary path optimisation for emergency vehicles based on the safety evaluation of intersections in an uncertain environment. First, the associated benefit calculation of emergency priority for vehicles passing through the nodes and road sections is provided then. Second, a mathematical description of the emergency vehicle path optimisation model is proposed, and its primary optimisation objective is to minimise travel time. A secondary optimisation objective based on a flexible time window is proposed to optimise the risk coefficient of the rescue path. Finally, an improved ripple-spreading algorithm is designed to find the optimal path. The findings can help to provide auxiliary decision support for the path selection of emergency rescue actions.

Editorial

This special edition curated by George Bouvier, the chair of the Luxury Plus Summit in 2022, delves into the imperative for the luxury industry to find safe passage through a perfect storm of challenging sociocultural events and shifting consumer behaviour. As the curtains rise one more time on the grand stage of fashion and luxury, contrasting viewpoints on brand purpose emerge, igniting spirited debates between worthy aspirations and the unyielding protection of the bottom line, critiques on brand heritage, social responsibility, environmental sensitivity and the elusive pursuit of consumer trust, weaving a tapestry of thought-provoking notions. With their intellectual finesse, these articles offer tantalizing glimpses into what appears to be the chrysalis phase of a metamorphosing industry, beckoning intrepid scholars and lovers of luxury alike to embark on a fascinating journey into the new unchartered frontiers of luxury.

Time for “environmentarian corridors”? Investigating the concept of safe passage to protect the environment during armed conflict

AbstractActors engaging in a diverse set of environmental protection activities are experiencing serious difficulties executing their mandates during armed conflict, leading to environmental harm that could otherwise have been mitigated. This article examines to what extent the international legal and policy framework can ensure the protection of environmental protection actors during armed conflict. It is argued that environmental protection actors can be seen either as part of civil defence organizations or as humanitarian relief actors, and are therefore covered by special protections under international humanitarian law. However, two main challenges remain: (1) despite these existing provisions, environmental protection actors may still face access and safety issues during armed conflict, and (2) within this framework, environmental protection activities must be linked to civilian needs and cannot be conducted based on ecocentric motivations. To overcome these challenges, the article introduces the concept of “environmentarian corridors”. Environmentarian corridors would allow for the unimpeded movement of environmental protection workers and resources through contested territory and into emergency areas to protect the environment. They would also serve to increase awareness about obligations to protect the environment and would help to ensure the safety of environmental protection actors during armed conflict, as the role and mandate of these actors is explicitly accepted by stakeholders. Additionally, environmentarian corridors offer potential for conducting environmental protection activities on ecocentric grounds. The article concludes by advocating for stakeholders to employ the provisions and concepts articulated herein as a means to further promote and strengthen initiatives aimed at protecting the environment during armed conflict.

Alcohol exposure before and during pregnancy is associated with reduced fetal growth: the Safe Passage Study

BackgroundPrenatal alcohol exposure (PAE) is a worldwide public health concern. While PAE is known to be associated with low birth weight, little is known about timing and quantity of PAE on fetal growth. This study investigated the association between periconceptional and prenatal alcohol exposure and longitudinal fetal growth, focusing on timing and quantity in a high exposure cohort.MethodsThe Safe Passage Study was a prospective cohort study, including 1698 pregnant women. Two-dimensional transabdominal ultrasound examinations were performed to measure fetal femur length, abdominal and head circumference, and biparietal diameter, at three time points during pregnancy. Estimated fetal weight and Z-scores of all parameters were calculated. Trimester-specific alcohol exposure was assessed using the Timeline Followback method. To investigate the associations of specific timing of PAE and fetal growth, two models were built. One with alcohol exposure as accumulative parameter over the course of pregnancy and one trimester specific model, in which PAE was separately analyzed. Linear mixed models adjusted for potential confounders were applied with repeated assessments of both alcohol exposure and fetal growth outcomes.ResultsThis study demonstrated that periconceptional and prenatal alcohol exposure were associated with reduced fetal growth. Effect sizes are displayed as estimated differences (ED) in Z-score and corresponding 95% confidence intervals (95% CIs). When investigated as accumulative parameter, PAE was related to a smaller femur length (ED30; − 0.13 (95% CI; − 0.22; − 0.04), ED36; − 0.14 (95% CI; − 0.25; − 0.04)) and a smaller abdominal circumference (ED36; − 0.09 (95% CI; − 0.18; − 0.01)). Periconceptional alcohol exposure was associated with a smaller abdominal circumference (ED30; − 0.14 (95% CI; − 0.25; − 0.02), ED36; − 0.22 (95% CI; − 0.37; − 0.06)) and a smaller estimated fetal weight (ED36; − 0.22 (95% CI; − 0.38; − 0.05)). Second trimester alcohol exposure was associated with a smaller abdominal circumference (ED30; − 0.49 (95% CI; − 0.86; − 0.12), ED36; − 0.70 (95% CI; − 1.22; − 0.17)) and estimated fetal weight (ED30; − 0.54 (95% CI; − 0.94; − 0.14), ED36; − 0.69 (95% CI; − 1.25; − 0.14)). No additional association of binge drinking was found besides the already observed association of PAE and fetal growth.ConclusionsThis study demonstrated that PAE negatively affects fetal growth, in particular when exposed during the periconception period or in second trimester. Our results indicate that potential negative consequences of PAE are detectable already before birth. Therefore, healthcare providers should actively address and discourage alcohol use during pregnancy.

Associations between prenatal alcohol and tobacco exposure on Doppler flow velocity waveforms in pregnancy: a South African study

BackgroundThe negative impact of prenatal alcohol and tobacco exposure (PAE and PTE) on fetal development and birth outcomes are well described, yet pathophysiologic mechanisms are less clear. Our aim was to investigate (1) the associations between quantity, frequency and timing (QFT) of PAE and PTE with blood flow velocities in arteries of the fetal-placental-maternal circulation and (2) the extent to which combined effect of QFT of PAE and/or PTE and Doppler flow velocity waveforms (FWV) predict infant birth weight.MethodsThe Safe Passage Study is a cohort based in urban Cape Town, South Africa. Recruitment occurred between 2007 and 2015. Information on QFT of PAE and PTE was collected prospectively at up to 4 occasions during pregnancy using a modified Timeline Follow-Back approach. Ultrasound examinations consisted of Doppler flow velocity waveforms of the uterine, umbilical (UA) and fetal middle cerebral arteries for the pulsatility index (PI) at 20–24 and 34–38 weeks. Exclusion criteria included: twin pregnancies, stillbirths, participants exposed to other drugs. The sample was divided into three groups (controls, PAE and PTE) and included 1396 maternal-fetal-dyads assessed during the second trimester; 1398 assessed during the third trimester.ResultsPTE was associated with higher UA PI values in second and third trimesters (p < 0.001), compared to the PAE and control group. The total amount of cigarettes smoked during pregnancy was positively correlated with UA PI values (r = 0.087, p < 0.001). There was a positive correlation between cigarettes smoked per day in trimester one (r = 0.091, p < 0.01), and trimester two (r = 0.075, p < 0.01) and UA PI (in trimester two), as well as cigarettes smoked per day in trimester two (r = 0.058, p < 0.05) and trimester three (r = 0.069, p < 0.05) and the UA PI in trimester three. Generalized additive models indicated that PAE in trimester two, PTE in trimester one and Doppler FWV in trimester three were significant predictors of birth weight in this sample.ConclusionIn our study, PTE in trimesters two and three resulted in increased vascular resistance of the placenta. These findings highlight nuance in associations between PAE, PTE and blood flow velocities in arteries of the fetal-placental-maternal circulation and birth weight, suggesting that quantity and timing are important factors in these relationships.

Cognitive models for mentally visualizing a sharp instrument in a blind procedure.

Our objective was to understand the cognitive strategies used by surgeons to mentally visualize navigation of a surgical instrument through blind space. We conducted semi-structured interviews with 15 expert and novice surgeons following simulated retropubic trocar passage on 3D-printed models of pelvises segmented from preop MRIs. Midurethral sling surgery involves blind passage of a trocar among the urethra, bladder, iliac vessels, and bowel while relying primarily on haptic feedback from the suprapubic bone (SPB) for guidance. Our conceptual foundation was based on Lahav's study on blind people's mental mapping of spaces using haptic cues. Participants detailed how they mentally pictured the trocar's location relative to vital anatomy. We coded all responses and used constant comparative analysis to generate themes, confirmed with member checking. Expert and novice participants utilized multiple cognitive strategies combined with haptic feedback to accomplish safe trocar passage. Some used a step-by-step route strategy, visualizing sequential 2D axial images of anatomy adjacent to the SPB. Others used a map strategy, forming global 3D pictures. Although these mental pictures vanished when they were "lost," a safe zone could be reestablished by touching the SPB. Experts were more likely to relate their body position to the trocar path and rely on minor variations in resistance. Novices were more inclined toward backtracking of the trocar. Our findings may be extended to any blind surgical procedure. Teaching visualization strategies and incorporating tactile feedback can be used intraoperatively to help learners navigate their instrument safely around vital organs.

Counter-maps of body-territory: Gender-based violence in Mexico

This paper is an exercise in counter-mapping gender-based violence, both its lived experience and the need for safe passage. Building on the concept of body-territory introduced by feminist geographers in Latin America, gender-based violence is plotted by its would be objects: female/feminized bodies. Each counter-map is drawn by those immediately moved by violence, by those forced to navigate its deadly consequences. William James offers insight into the spatio-temporal implications of this experience, revealing how the extensive lines of a counter-map are born of intensities felt in sensation and later reflected on in thought. Counter-maps are drawn by thinking-feeling bodies to break with any fixed domain: plotted are individual memories and shared pieces of advice that are accumulated across time to give the map a unique history, and that encompass diverse events to give the map a unique spatiality. Mapped is the experience of gender-based violence in Puebla, Mexico, so as to challenge official cartographic practices and rework their deadly effects.

Risk of Injury to Retroperitoneal Structures in Prone and Lateral Decubitus Transpsoas Approaches to Lumbar Interbody Fusion: A Pilot Cadaveric Anatomical Study.

Introduction The retroperitoneal approach for lateral lumbar interbody fusion (LLIF) originally described an initial posterolateral fascial incision enabling finger dissection from behind the peritoneum and guidance of instruments through a second direct-lateral fascial incision. It has since become common for single direct-lateral incisional access to the retroperitoneum. This study attempted to quantify the distance of the peritoneum from posterior landmarks in the space, assess the risk of peritoneal violation in each access trajectory (i.e., posterolateral versus direct lateral retroperitoneal dissection), and determine whether there are differences based on patient position (prone versus lateral decubitus). Methods In three prone cadaveric torsos, Steinman pins were percutaneously placed mid-disc at each level L2-5 bilaterally (for a total of 18 prone approaches). Open dissections exposed the retroperitoneum including the quadratus lumborum and psoas muscles, maintaining the natural reflection of the peritoneum. Visual assessment qualified whether any pin violated any retroperitoneal structure. Distance from the anterior border of the quadratus lumborum to the posterior-most reflection of the peritoneum was measured. For comparison, three additional torsos were positioned in lateral decubitus, and the above steps were repeated, only unilaterally (for a total of nine lateral decubitus approaches). Results In prone, no pin violated the peritoneum; three (3/18 total approaches) violated the kidney, all at L2-3 (3/6 approaches at L2-3). In lateral decubitus, all three L2-3 pins violated the kidney (3/3 approaches at L2-3); five of the six remaining pins from L3-5 violated the peritoneum (totaling eight violations in the nine total approaches). The incidence of any violation was significantly greater in lateral decubitus vs. prone (8/9 vs. 3/18, p=0.0006). The structure at risk (kidney vs. peritoneum) was significantly associated with disc level (p=0.0041): all kidney violations occurred at L2-3 and all peritoneal violations occurred at L3-4 or L4-5. Distance from the quadratus lumborum to the posterior-most reflection of the peritoneum averaged 8.7 cm (range: 6-10) in prone, and 2.9 cm (range: 2.5-3.2) in lateral decubitus (p=0.0129). Conclusion A cadaveric study of retroperitoneal anatomy demonstrates that there is an increased distance from the quadratus lumborum to the peritoneum in prone versus lateral decubitus and that the trajectory of approach to the lumbar discs risks violation of the peritoneum more frequently when accessing directly laterally versus posterolaterally. In either approach, care should be taken to identify and release the peritoneal reflection to create a safe passage to the lumbar discs.

A multi-objective optimisation strategy for ice navigation under ship safety-following scenarios

Shipping activities in the Northern Sea Route (NSR) are increasing. However, due to the complex sea ice conditions, ships still need assistance of icebreakers when sailing through most Arctic waters. Icebreaker escort operations are important to ensure the safe passage of ships through ice-covered waters, but the speed of following ships will be limited, thus creating challenges for NSR sailing economics and emission reduction issues. Optimizing the sailing speed of following ships can reduce NSR ship emissions and improve navigation economy while safeguarding their sailing safety. In this paper, a green, economical and safe optimization approach under ship-following navigation has been developed by drawing on similarities with the car-following phenomenon. Then, three ship-following scenarios are designed for simulating the actual ice navigation conditions. Finally, a cost-eco-efficiency multi-objective optimisation model for ice navigation is established, and the performance of the proposed model is demonstrated by the navigation case of “Tian You”. The results show that the proposed model can effectively reduce navigation costs and control navigation emissions while ensuring navigation safety. This study also demonstrates that there is still room for a 20% improvement in the optimised speed and a 4.8% reduction in the ship-following distance compared to the actual situation.

Dynamic Inversion Model of the Mooring Force on a Floating Bollard of a Sea Lock

Sea locks that connect inland canals and rivers to the open sea are crucial links that ensure the efficient navigation of ships. Floating bollards (FBs) are significant components of sea locks, and they are affected by factors such as large ships, speed of entry, and irregular mooring lines coupled with corrosion by chloride salts from seawater intrusion from the environment. These factors aggravate damage to metal structures, which seriously threatens the safety of FBs. Overloading of FBs by mooring forces caused by the illegal use of FBs for the braking of large ships that enter locks at excessive speed is the main cause of structural damage and overload failure for FBs. Controlling the dynamic mooring force acting on the FB is an important prerequisite to ensure the safe passage of a ship through a lock. It is impossible to perform real-time monitoring of the magnitude and direction of the mooring force on an FB by installing load-measuring equipment on the mooring line. Therefore, in this study, the structure of an FB in a sea lock project was taken as an example, and the mathematical relationships between the strain in the load-sensitive area of the FB and the mooring force and the mooring angle were quantified. A dynamic inversion model of the ship mooring force on an FB was proposed. This model used real-time feedback from the strain signal in the load-sensitive region of the FB structure to obtain information about the mooring force. The accuracy of the model was verified by conducting tests with a physical model of the topside structure of the FB and comparing the predicted results with the test data. The research results can lay a theoretical foundation for real-time monitoring of the structural response of an FB under the action of mooring forces and promote the development of intelligent methods for the operation and maintenance of a sea lock, which have important scientific significance and engineering value.

Assessment of the Attractiveness and Passage Efficiency of Different Fish Passage Solutions at a Hydropower Plant by Combining Fine Scale 2D-Telemetry and Hydraulic Numerical Modelling

Mitigation measures for downstream-migrating Atlantic salmon smolts (Salmo salar L.) are commonly insufficiently attractive to enable safe entrance and passage with no delay. Combining 2D telemetry with hydrodynamic modelling has been shown to be a good tool to better understand the influence of hydrodynamic factors on the migration route choice of fishes. In this study, we investigated the smolt downstream migration at a hydropower plant in Belgium that offers five migration routes, including two Archimedes screws and one nature-like fishway. At the hydropower plant, the Archimedes screws were the most used migration routes, due to higher discharges and more important water depths at their entrance. The weir and the canal intake were less used by the smolts. The nature-like fishway turned out to be less used, with 23% of the smolts. Its associated crossing time was significantly longer, probably due to shallow water depths and high flow velocities. The nature-like fishway had the potential to become a good migration route for salmon smolts after improvements to increase attractiveness and passage efficiency. Moreover, the Archimedes screws were not detrimental to the smolts and did not cause any significant delays to the crossing time.

Vehicular Visible Light Communication for Intersection Management

An innovative treatment for congested urban road networks is the split intersection. Here, a congested two-way–two-way traffic light-controlled intersection is transformed into two lighter intersections. By reducing conflict points and improving travel time, it facilitates smoother flow with less driver delay. We propose a visible light communication system based on Vehicle-to-Vehicle (V2V), Vehicle-to-Infrastructure (V2I) and Infrastructure-to-Vehicle (I2V) communications able to safely manage vehicles crossing through an intersection, leveraging Edge of Things (EoT) facilities. Headlights, street lamps, and traffic signals are used by connected vehicles to communicate with one another and with infrastructure. Through internally installed Driver Agents, an Intersection Manager coordinates traffic flow and interacts with vehicles. For the safe passage of vehicles across intersections, request/response mechanisms and time and space relative pose concepts are used. A virtual scenario is proposed, and a “mesh/cellular” hybrid architecture used. Light signals are emitted by transmitters by encoding, modulating, and converting data. Optical sensors with light-filtering properties are used as receivers and decoders. The VLC request/response concept uplink and downlink communication between the infrastructure and the vehicles is tested. Based on the results, the short-range mesh network provides a secure communication path between street lamp controllers and edge computers through neighbor traffic light controllers that have active cellular connections, as well as peer-to-peer communication, allowing V-VLC ready cars to exchange information.

Decomposition of the induced magnetism degaussing problem for fast determination of currents in demagnetization coils wrapped outside an object under arbitrary external field conditions

Safe passage of ships in the presence of sea mines can be ensured by limiting or reducing the ship’s magnetic footprint. For vessels with plastic hulls, the main component that requires magnetic damping is the engine. Demagnetization of such an object can be achieved by wrapping it with coils and setting the direct current appropriately. For each specific geographic location, the currents in the coils can be determined iteratively from measurements of the magnetic signature in the cardinal directions. In this paper the magnetic signatures are calculated using decomposition-based approach for each coil and each component of the external field separately. Hence the overall magnetic signature of the object can be reproduced in arbitrary external magnetic field (i.e. anywhere on the Earth). Knowing the influence of each coil, it is possible to formulate the optimization task (signature minimization) and determine the currents. The presented method is verified in FEM software with the use of engine models of both symmetrical and asymmetrical shapes. Since the determination of the currents takes place as a result of solving the optimization problem, the effectiveness of obtaining the results, the speed of convergence and the dependence on initial conditions is under investigation. The effect of the model mesh size on the quality of object signature reduction is also analyzed. The developed method can be used for a real object. In that case acquiring the data then requires the measurements of the object placed inside the Helmholtz coils.

Mechanism of adult emergence in Xanthopimpla pedator (Fabricius)- a major pupal parasitoid of Tasar silkworm

Aim: The study was conducted to elucidate the mechanism involved in adult emergence behavior of Xanthopimpla pedator a pupal parasitoid of tasar silkworm. Methodology: Behavioral observations were made to study the mechanical approaches used during emergence and SDS-PAGE analysis was carried to know the possibility of proteases in the digestive secretions. Results: The findings of the study suggest that X. pedator uses physical and chemical to achieve safe passage from the host pupae and cocoons. It was observed that during the process of emergence, X. pedator breaks host pupae by means of mandibular action (by biting the pupal shell). Further, it was noticed that to make emergence hole on host cocoon X. pedator found to employ digestive secretion to soften and disintegrate the silken shell, besides it also deploys mandibles to spread out the secretion on intended place of exit hole. SDS-PAGE analysis showed the presence of series of enzymes, possibly involved in cocoon softening. Interpretation: Findings of this study forms the basis that X. pedator, a major pupal parasitoid of tasar silkworm, uses both physical and chemical approaches to achieve safe passage from the host pupae and protective silken cocoon. Key words: Digestive secretion, Mandibular action, Parasitization, Xanthopimpla pedator