Dead Area Research Articles

Detection of Direct Sun Glare on Drivers from Point Clouds

Sunlight conditions can reduce drivers’ visibility, which is a safety concern on road networks. This research introduces a method to study sun glare incidence in road environments. Sun glare areas during daylight hours are automatically detected from mobile laser scanning (MLS) and aerial laser scanning (ALS) point clouds. The method comprises the following steps. First, the Sun’s position (solar altitude and azimuth) referring to a location is calculated. Second, the incidence of sun glare with the user’s angle of vision is analyzed based on human vision. Third, sun ray intersections with near obstacles (vegetation, building, etc.) are calculated utilizing MLS point clouds. Finally, intersections with distant obstacles (mountains) are calculated utilizing ALS point clouds. MLS and ALS data are processed in order to combine both data types, remove outliers, and optimize computational time for intersection searches (point density reduction and Delaunay triangulation). The method was tested on two real case studies, covering roads with different bearings, slopes, and surroundings. The combination of MLS and ALS data, together with the solar geometry, identify areas of risk for the visibility of drivers. Consequently, the proposed method can be utilized to reduce sun glare, implementing warnings in navigation systems.

Sward structure, morphological components and forage yield of massai grass in response to residual effect of swine biofertilizer

The present study aimed to evaluate the residual effects of the application of biofertilizer and mineral fertilizer on sward structure and morphological components of Panicum maximum cv. Massai. The experimental design comprised randomized blocks with six treatments consisting of increasing doses of swine biofertilizer (0, 10, 20, 30 and 40 Mg ha-1) and mineral fertilization (150 kg N ha-1, 33 kg P ha-1), with four replicates. The variables analyzed were pasture height, light interception, leaf area index, forage mass and morphological components. Plant height responded linearly and positively to biofertilizer levels in the three evaluations. The highest averages for light interception (51.63%) and leaf area index (1.64) were observed for the 240 days (40 Mg ha-1). Dry leaf mass was influenced by the increase in biofertilizer dose, with increments of 39.68%, 25.07% and 44.66% for the 240, 300 and 360 days, respectively, when compared to the control treatment. Mineral fertilization promoted lower mass of dead material and lower leaf area index but did not differ from biofertilizer for the other variables. The residual effect of swine biofertilizer was greater than that of mineral fertilization, with a minimum use of 20 Mg ha-1 a practical agronomic recommendation.

Velocity Gradient Optimization in a Perforated Tray-Type Flocculator using OpenFOAM: CFD as a Tool in Water Treatment

Analysis of the velocity gradient of flocculators through Computational Fluid Dynamics (CFD) simulation can be essential to the optimization of hydraulic conditions in Water Treatment Plants. This study aims to simulate the velocity field in the last tank of a perforated tray-type flocculator and quantify locally velocity gradient (G) through CFD. This stage of flocculation has a higher risk of flocs rupture when there are not adequate conditions. Thus, simulations occurred at the flocculator current operational flow rate (7 ls-1), and at full capacity (9 ls-1). An alternative cost-effective and easy to implement modification was tested by increasing the number of orifices in the flocculator trays. As result, the velocity field indicates the formation of dead zones at the edges of the tank for all simulations, which facilitates short circuit occurrences. This is an indicator of reductions in water treatment efficiency. After structural modifications, simulations indicate a reduction in dead zone areas. Plus, as the flow rate increases, the maximum G inside the structure increases considerably (184 to 266 s-1), causing a risk for floc rupture. However, changing the number of orifices from 22 to 33 creates conditions for the flocculator to operate at higher flow rates without increasing the velocity gradient.

MINAWISATA PERIKANAN AIR PAYAU DI DESA SUNGAI CUKA TANAH LAUT

The brackish water aquaculture area in Sungai Cuka Village used to be the location of a pond that produced a lot of brackish water fish such as Milkfish (Chanos chanos), Windu Shrimp (Penaeus monodon), Mullet (Mugil cephalus), Mangrove Crab (Scylla serrata), White Snapper ( Lates calcarifer), and others. Coal mining has begun to be opened upstream of the estuary so that coal waste is carried downstream and pollutes the pond water which causes the ponds to die. This has an impact on the income of the fishermen who began to decline, finally they decided to leave the pond to look for other livelihoods. So the problem raised is how to design a brackish water aquaculture educational recreation area with a regional locality approach? This writing aims to restore aquaculture activities in Sungai Cuka Tanah Laut Village as an effort to revive dead aquaculture areas and settlements supported by pond water conditions that are free from coal waste pollution. The step to achieve the goal is to design a brackish water fishery tourism area based on educational recreation tourism. The method applied is a contextual architectural approach which is expected to maintain the characteristics of the coastal area, can renew the image of the aquaculture area which is slowly disappearing, and become a recreational tourism and fisheries education area.

Head check resistance of B320 bainitic rail steel grade

This work focuses on the degradation mechanisms of a B320 carbide-free bainitic steel grade rail and of its weld after laboratory tests. The microstructure of the tested rails is investigated, focusing mainly on retained austenite. The Head Check resistance of B320 grade base material is high, notably due to the TRansformation Induced Plasticity (TRIP) effect, inducing a reduction in crack propagation speed. Inside the Heat Affected Zone, a few Head Check defects have been detected and are attributed to a lower retained austenite content coming with a higher Martensite-Austenite Compound content prior to rail testing. In this zone, the transformation process from austenite to martensite following TRIP effect is less pronounced. A novel degradation mechanism is proposed considering the phases contribution in the deformation process of B320 carbide free steel grade.

Inclusion Removements in a Bottom-Stirring Ladle with Novel Slot-Porous Matched Dual Plugs

The cleanness of steel has always been a big problem for secondary refining. In this work, a new method, which is coupled with slot and porous plugs, is proposed to improve the cleanness in steel. Water experiments and numerical simulations were performed to study this effect. Results revealed that when using slot-porous plugs, the flow field was obviously asymmetrical, and the circulation flow was pushed towards the porous side. Then, the removement of inclusions was increased to about 22.7% percent, comparing with traditional two-slot bottom stirring and reducing the dead zone area near the bottom of the ladle; however, the mixing time delay was 16%, comparing with traditional plugs. Then, in order to explain the reason for these phenomena, we established a mathematical model through large eddy simulation and discrete particle modeling (DPM). Results shows that the asymmetry flow field awoke the recirculation flow downwards after using slot-porous plugs, which would homogenize the flow at the bottom, promoting floating in steel. What is more, the velocity near the free surface was lowered; therefore, it could also stabilize the surface velocity as well, which is also beneficial for removing inclusions as well.

A comparison of daytime and nighttime pedestrian road-crossing behavior using an immersive virtual environment

Objective Reduced visibility for both drivers and pedestrians is a key factor underlying the higher risk of vehicle-pedestrian collisions in dark conditions. This study investigated the extent to which pedestrians adjust for the higher risk of road crossing at night by comparing daytime and nighttime pedestrian road crossing using an immersive virtual environment. Method Participants physically crossed a single lane of continuous traffic in an immersive pedestrian simulator. Participants were randomly assigned to either the daytime or the nighttime lighting condition. The primary measures were the size of the gap selected for crossing and the timing of crossing motions relative to the gap. Results The results showed that there were no significant differences in gap selection or movement timing in daytime vs. nighttime lighting conditions. However, there was a marginal increase in the time to spare after crossing the road when crossing in the dark, likely due to an accumulation of small differences in gap choices and movement timing. Conclusion This study suggests that pedestrians do not adjust their road crossing to account for greater risk at night. As such, this study adds to our understanding of the potential risk factors for pedestrian injuries and fatalities in nighttime conditions.

Design of The CRONE Automatic Headlight Leveling System

Automotive headlights system represents a safety key system when it comes to drive by night. It aims to increase the comfort of the driver by providing a clear visibility in order to anticipate obstacles and follow the right path. One of the main challenges that the lighting system is facing today is its automatic leveling adjustment. Variations of load of the vehicle, its dynamics and the environment are the main sources of disturbance to the leveling system. These disturbances causes variations of vehicle pitch angle and as a result the lighting cut-off level that may glare other road users and affect the driver's visibility range. This paper proposes an innovative automatic leveling system based on an ultrasonic motor which is able to dynamically reject such disturbances on the lighting cut-off level using a robust CRONE controller.

Expanding the speciation of terrestrial molybdenum: Discovery of polekhovskyite, MoNiP2, and insights into the sources of Mo-phosphides in the Dead Sea Transform area

Abstract Polekhovskyite, MoNiP2, is the first terrestrial Mo phosphide, a phosphorus-rich homolog of meteoritic monipite, MoNiP. The mineral represents a novel phosphide type of terrestrial Mo speciation. It was discovered among phosphide assemblages in pyrometamorphic rocks of the Hatrurim Formation (the Mottled Zone) in Israel, the area confined to the Dead Sea Transform fault system. Polekhovskyite occurs in the altered diopside microbreccia, as micrometer-sized euhedral crystals intimately intergrown with murashkoite, FeP and transjordanite, Ni2P, in association with Si-rich fluorapatite, hematite, and magnetite. In reflected light, the mineral has a bluish-gray color with no observable bireflectance and anisotropy. Chemical composition (electron microprobe, wt%): Mo 44.10, Ni 22.73, Fe 4.60, P 29.02, total 100.45, which corresponds to the empirical formula Mo0.99(Ni0.83Fe0.18)1.01P2.01 and leads to the calculated density of 6.626 g/cm. Polekhovskyite is hexagonal, space group P63/mmc, a = 3.330(1), c = 11.227(4) Å, V = 107.82(8) Å3, and Z = 2. The crystal structure has been solved and refined to R1 = 0.0431 based on 50 unique observed reflections. The occurrence of Mo-bearing phosphides at the Dead Sea Transform area is a regional-scale phenomenon, with the localities tracked across both Israel and Jordan sides of the Dead Sea. The possible sources of Mo required for the formation of Mo-bearing phosphides are herein reviewed; they are likely related to the processes of formation of the Dead Sea Transform fault system. The problem of anthropogenic contamination of geological samples with Mo and Ni is also discussed in the paper in the context of the general aspects of discrimination between natural and technogenic ultra-reduced phases.

ERGONOMIC DESIGN OF CAB STRUCTURE FOR WHEELED COMBINE HARVESTER

In view of the fact that the design of the cab structure of wheeled combine harvesters in China lacks ergonomic design parameters exclusive for Chinese drivers, there are generally problems such as high vibration and poor comfort of the whole machine structure during the harvesting process. Firstly, this paper designed the cab structure of a wheeled grain combine harvester based on ergonomics. Then, the driver's handling comfort and visibility were simulated and analyzed using Creo. Finally, the relevant dimensions of the driver's control device were optimized. The results show that the wheeled grain combine harvester cab based on ergonomic design better meets their driving comfort needs. In addition, it is found that the operating frequencies of the key components, such as the main shaft of the conveyor spindle, the vibrating screen, the threshing drum, and the intermediate shaft of the engine, partially overlap with the frequency of human discomfort. Therefore, modal planning is also needed for this harvester to meet human comfort requirements better. This paper provides the basic parameters for the design of the cab structure of the combine harvester with high comfort for the Chinese harvesting machinery driver.

Focus on Tank truck drivers Vision in ensuring Safe Road transportation of hazardous petroleum products

Focus on Tank truck drivers Vision in ensuring Safe Road transportation of hazardous petroleum products

Paper] Driver Visibility Improvement using Spatial Augmented Reality with Pixelated Headlights

Paper] Driver Visibility Improvement using Spatial Augmented Reality with Pixelated Headlights

Innovative Glass-Powder Paint Technology for Improving Driver Visibility at Night: Case Study CBD Access Road, East London, Eastern Cape Province South Africa

Driving at night or in low visibility regions along a transportation facility can be particularly dangerous. Related problems range from, reduction in visibility and the objects fading away into obscure darkness with reduced illumination. In scenarios as this, the road markings become blur and eventually disappear along the driving lane. Although, some drivers suffer from night vision deficiency (nearsightedness, cataracts, retinis pigmentosa); resulting to conditions that damage their vision at night. Sometimes reduced vision can be caused by wearing away of the road markings over time by rains and friction between tyre and the road marking lines. This study provides an alternative measure to improve driver visibility at night using glass-powder paint technology (GPPT). This method is proposed to be implemented as an innovation towards reducing glass waste from landfills and dump sites and recycling glass waste to improve road markings within urban cities and highway corridors. A case study section is introduced for testing in East London CBD drive way (Eastern Cape Province-South Africa) and compared with a different marked road using conventional road marking paint. The study was conducted using quantitative analysis (grouped multinomial logistics and non-parametric test) in quantum flow theory which proves that there exist a strong relationship between improved driver visibility on road markings with the introduction of the innovative Glass Powder Paint Technology. This further helps to improve glare and illumination at night while enhancing driver behavior with regards to perception and positioning of objects on the roadway and increased illumination index of road markings. This confidence level of 95% equivalent to a 0.05 null hypothesis significance level assumed in which the null hypothesis was rejected indicates improvement in driving behaviour at night on the test section with the introduction of the GPPT to enhance illumination index and reduce level of blur on the road markings and objects along the road section.

Enhancing driver visibility at night: an advanced glass-powder paint technology approach

Enhancing driver visibility at night: an advanced glass-powder paint technology approach

Structure simulation design of a cathode air filter for SO2 contamination on a 7 kW fuel cell sightseeing vehicle

Proton exchange membrane (PEM) fuel cell stacks can be severely poisoned by a trace amount of SO2 in the atmosphere, making it necessary to install an air filter to remove harmful contaminants from the cathode air. This study utilizes Computational Fluid Dynamics (CFD) to investigate the influence of the diverse filter structure design containing combinations of inlet diversion tube length and outlet deflector shape on the hydrodynamics and adsorption performance of a cathode air filter by Fluent. Simulation results show that the air filter performance is enhanced with decreases in diversion tube length. Compared with the horizontal porous plate, the conical one increases the pressure drop and the SO2 adsorption dead zone area. Besides, an air filter prototype made based on the simulation results was applied to a 7 kW fuel cell sightseeing vehicle for the field test. The maximum voltage value of the stack is 73.1 V, the minimum is 67.6 V, and the maximum difference is 5.5 V when the fuel cell sightseeing vehicle runs at a constant speed of 20 km/h 77% of the voltage value is stable between 69 and 71 V, which proves the stable operation of the stack.

800-MHz Bandwidth Signal Transmission with Radio over Multi-Mode-Fiber for Cascaded IFoF-Based C-RAN Mobile Fronthaul

Millimeter-wave band signals have the advantage of a high capacity and have been used in fifth-generation (5G) mobile services. An analog radio over multi-mode fiber (A-RoMMF) employing a directly modulated vertical cavity surface emitting laser is a promising technology for relaying millimeter-wave band signals to its dead area because of the advantages of low latency, low cost, and low power consumption. One of the applications of A-RoMMF is a cascaded intermediate-frequency-over-fiber (IFoF)-based centralized radio access network (C-RAN) mobile fronthaul (MFH) system. We conducted two studies on A-RoMMF to extend the transmission distance and bandwidth to adapt it to the system. First, we evaluated the effect of employing a single-mode vertical cavity surface emitting laser (VCSEL) and a multi-mode VCSEL on the transmission characteristics of A-RoMMF. Next, we evaluated the transmission characteristics of A-RoMMF using a cost-efficient bias-tee consisting of an electrical circuit pattern, the frequency response of which has a slope inverse to that of A-RoMMF at the 28-GHz band, to suppress the channel power difference of two component carrier signals for a wide-bandwidth signal transmission. We conducted these evaluations using A-RoMMF itself and herein demonstrate its adaption to a cascaded IFoF-based C-RAN MFH system at the 28-GHz band. When employing it with a 200-m long multi-mode fiber, the system achieves 400-MHz/CC and two component carrier signal transmissions.

Characterisation of the HEXITEC[formula omitted] X-ray spectroscopic imaging detector incorporating through-silicon via (TSV) technology

In this paper a new version of the HEXITEC spectroscopic imaging technology is presented. The HEXITEC4S ASIC maintains the same pixel electronics but, unlike the previous design, contains no I/O pads on the top surface of the ASIC. The I/O pads, used for control and readout, are now produced on the bottom metal layer of the ASIC and are accessed using a deep through-silicon via process (TSV) developed by TMicro (Japan). Wire bonding then takes place on a redistribution layer produced on the rear surface of the ASIC. The use of this TSV processing means that devices are four-side-buttable and can be used to produce detectors from multiple modules with minimal dead area. TSV processing was completed on two wafers of HEXITEC4S devices and probe testing demonstrated a working ASIC yield of 75% and 43% for the two wafers. In order to test the performance of detectors, a 100 mm diameter wafer of spectroscopic grade GaAs:Cr was fabricated by Tomsk State University (Russia). The wafer consisted of HEXITEC4S and standard HEXITEC devices which allows the performance of the TSV detectors to be compared to those of the standard system using sensor material with near-identical properties. A comparison of the spectroscopic performance of these devices demonstrated a relatively minor difference between the HEXITEC4S and HEXITEC devices with FWHM@60keV measured to be 4.1 keV and 4.5 keV respectively. These results demonstrate that this deep TSV processing for the redistribution of the detector I/O can be successfully used to produce flat panels of HEXITEC detectors with minimal dead area between modules.

Estimation of changes in the Dead Sea surface water area through multiple water indices and geospatial techniques

<p>The study calculated the changes in the Dead Sea surface area from 1984 to 2019. The satellite images of 1985, 1990, 2000, 2010, and 2019 were classified by applying four different methods to estimate the changes in the Dead Sea surface water area. The methods included normalized difference water index (NDWI), modified normalized differences water index (MNDWI), automated water extraction Index (AWEI), and ISO cluster unsupervised classification. The results revealed a decrease of 76.63 sq. km area that accounts for an average of 11.27% sea area. The statistical model predicted that the Dead Sea surface area will shrink by half within the next 143 years, and the sea will be completely dried by 2305 if appropriate measures are not taken by decision-makers to avoid further reduction of the surface area.</p>

Automotive Lighting Technology for Driver's Visibility Improvement Using Imperceptible Pattern Illumination

Automotive Lighting Technology for Driver's Visibility Improvement Using Imperceptible Pattern Illumination

Driving behavior at midblock crosswalks with Rectangular Rapid Flashing Beacons: Hidden Markov model approach using naturalistic data

Pedestrian fatalities have increased in the U.S. with the largest increase being observed on urban arterials and away from intersections. Rectangular Rapid Flashing Beacon (RRFB) has been widely implemented as a safety countermeasure to improve driver awareness and visibility of pedestrians, especially for midblock crosswalks. Studies show that drivers are more likely to yield to pedestrians at crosswalks with an RRFB. These studies are often based on a binary outcome of whether or not drivers yield to pedestrians. Nevertheless, it is also important to consider the drivers’ deceleration behavior as a dynamic process at these crosswalks and the impact of pedestrians being present or not. Understanding this dynamic behavior and the related circumstances can provide information on the design of alerting systems that help drivers make more appropriate decisions at these crosswalks to avoid a vehicle–pedestrian crash. This study examined this research topic using Hidden Markov Models (HMMs) and data from a naturalistic study. More specifically, four HMMs were applied to the naturalistic brake and jerk data from the Safety Pilot Model Deployment (SPMD) program given drivers’ intention to slow down, the RRFB activation status, and the presence of pedestrians. The time-based data sequence was converted to distance-based through a moving window to enhance result comparison and interpretation. Grid-search was used to select the best moving window parameters and the optimal number of hidden states. This study confirmed the high compliance at an activated RRFB when pedestrians were present. Even without pedestrians, one in five traversals showed drivers slowing down to less than 8.94 m/s (20 mph) within 35 m of the crosswalk. Model results further indicate that drivers started braking as far back as 180 m before the crosswalk and stopped braking from 70 m before the crosswalk at an activated RRFB without pedestrians. When there were pedestrians, drivers would start braking 20 to 30 m later but would brake more firmly and for longer. Finally, drivers were not likely to brake or decelerate when RRFB was off and no pedestrians were present.