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1.
Stapp Car Crash J ; 67: 180-201, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38662625

ABSTRACT

Understanding left-turn vehicle-pedestrian accident mechanisms is critical for developing accident-prevention systems. This study aims to clarify the features of driver behavior focusing on drivers' gaze, vehicle speed, and time to collision (TTC) during left turns at intersections on left-hand traffic roads. Herein, experiments with a sedan and light-duty truck (< 7.5 tons GVW) are conducted under four conditions: no pedestrian dummy (No-P), near-side pedestrian dummy (Near-P), far-side pedestrian dummy (Far-P) and near-and-far side pedestrian dummies (NF-P). For NF-P, sedans have a significantly shorter gaze time for left-side mirrors compared with light-duty trucks. The light-duty truck's average speed at the initial line to the intersection (L1) and pedestrian crossing line (L0) is significantly lower than the sedan's under No-P, Near-P, and NF-P conditions, without any significant difference between any two conditions. The TTC for sedans is significantly shorter than that for trucks with near-side pedestrians (Near-P and NF-P) and far-side pedestrians in Far-P. These insights can contribute to the ongoing development of accident-prevention safety systems for left-turning maneuvers at intersections.


Subject(s)
Accidents, Traffic , Automobile Driving , Pedestrians , Humans , Male , Motor Vehicles , Manikins , Adult , Female
2.
Sci Total Environ ; 892: 164349, 2023 Sep 20.
Article in English | MEDLINE | ID: mdl-37236450

ABSTRACT

The implementation of circular economy (CE) strategies has facilitated a comprehensive approach to waste management (WM) in university campuses. Composting food waste (FW) and biomass can mitigate negative environmental impacts and be part of a closed-loop economy. The compost can be used as a fertilizer, thereby closing the waste cycle. Implementing nudging strategies to promote effective waste segregation can help the campus move closer towards achieving neutrality and sustainability goals. The research was conducted at the Warsaw University of Life Sciences - WULS (SGGW). The University Campus is located in the south of Warsaw (Poland) and covers an area of 70 ha with 49 buildings. The SGGW campus generates selectively collected (glass, paper, plastic and metals, and biowaste) and mixed waste. Data were collected through a year-long report from the university administration. For the survey, waste data from 2019 to 2022 were obtained. The CE efficiency indicators of CE were measured. The indicators of CE efficiency for compost (Ic,ce) and plastic (Ipb,ce) showed Ic,ce at 21.05 %, which means that 1/5th of the waste generated on the campus can be introduced into the CE paradigm through composting, and the resulting value Ipb,ce of 19.96 % indicates that this amount can be reintroduced into the CE paradigm through its reuse. The results of the seasonality study showed that there were no statistically significant differences in the generated biowaste between the separated periods of the year, and the Pearson correlation coefficient (r = 0.068) provided additional confirmation. The weak correlation between the amount of biowaste generated and the average for each year (r = 0.110) also indicates a stable biowaste generation system that does not require a reduction or increase in the efficiency of waste processing, such as composting. By implementing CE strategies, university campuses can improve WM practices and achieve sustainability goals.


Subject(s)
Refuse Disposal , Waste Management , Humans , Universities , Food , Plastics
3.
Sci Total Environ ; 859(Pt 1): 160160, 2023 Feb 10.
Article in English | MEDLINE | ID: mdl-36375549

ABSTRACT

Composting facilities are habitats where biological materials are bio-oxidized. Biological waste represents a source of plant species diaspores and may promote changes in the species composition of the surrounding. The studied composting facility is situated in the Bohemian-Moravian Highlands, Czech Republic. Four sites, the composting pile and three habitats nearby were chosen of different use and disturbance conditions. Phytosociological plots were recorded in each of the habitat and the results were processed using multivariate analyses of ecological data. The information about plant species indication values was also analysed: (i) the relationship between soil disturbance and plant species occurrence, (ii) seed dormancy, (iii) seed bank, and (iv) vector of seed dispersion. During the research, 119 plant taxa were found in total. Conditions of the composting process (frequent disturbances, excessive available nutrients, enough water, and supply of new diaspores) represent a challenge for plant species. The presence of plant diaspores in the biowaste is a reason why the fundamental principle of appropriate composting process has to be adhered to. Another important task is to give attention to the methods determining the share of living diaspores in the final compost, which is still missing in practice. Compost might become a vehicle for spreading weeds. The capacity of vegetation to survive and multiply on the premises of composting facilities increases the importance of vegetation monitoring and control of the adjacent areas. The usual occurrence of rural brownfields near composting facilities increases the risk of diaspores being transmitted into biowaste or compost, thus increasing the share of undesirable viable diaspores. Composting facilities generate specific synanthropic conditions for the vegetation. Therefore, the composting facility projects should take into consideration the surrounding areas and vegetation management. It is recommended that the project should include semi-natural vegetation, which can create efficient barriers to the spreading of undesirable ruderal plant species. The novelty of this study is the confirmation that composting facilities and compost become a new factor affecting vegetation, which has been disregarded so far. The link between composting facilities and vegetation has to be included in the legislation related to parameters of compost quality. Moreover, the issue of weeds, their reproductive organs and their spread should be considered in the guidelines for the design, location, construction, and operation of composting facilities.


Subject(s)
Composting , Soil , Czech Republic
4.
Behav Sci (Basel) ; 12(11)2022 Oct 28.
Article in English | MEDLINE | ID: mdl-36354394

ABSTRACT

We investigated the effect of driver posture on driving control following a takeover request (TOR) from autonomous to manual driving in level 3 autonomous vehicles. When providing a TOR, driving behaviors need to be investigated to develop driver monitoring systems, and it is important to clarify the effect of driver postures. Experiments were conducted using driver postures that are likely to be adopted in autonomous driving. Driver postures were set based on combinations of two types of upper-body posture and three types of foot posture. The driver's upper body and head were set to either a forward or sideways orientation. For each of these there were three types of foot posture: both feet on the floor, crossed legs, and cross-legged sitting. Following a TOR, we compared the braking and steering maneuvers of subjects driving normally and examined the effects of posture on driver reaction time. The results show that both the upper-body and foot postures of the driver affect the steering and braking reaction time. The driver monitoring system should be able to detect posture and activate a TOR warning, and detection times up to 2 and 1.3 times faster than those for normal postures should be considered for different upper-body and foot postures, respectively.

5.
Stapp Car Crash J ; 66: 217-238, 2022 Nov.
Article in English | MEDLINE | ID: mdl-37733827

ABSTRACT

In Japan, where vehicles drive on the left side of the road, pedestrian fatal accidents caused by vehicles traveling at speeds of less than or equal to 20 km/h, occur most frequently when a vehicle is turning right. The objective of the present study is to clarify the driving behavior in terms of eye glances and driver speeds when drivers of two different types of vehicles turn right at an intersection on a left-hand traffic road. We experimentally investigated the drivers' gaze, vehicle speed, and distance on the vehicle traveling trajectory from the vehicle to the pedestrian crossing line, using a sedan and a truck with a gross vehicle weight of < 7.5 tons (a light-duty truck) during right-turn maneuver. We considered four different conditions: no pedestrian dummy (No-P), right pedestrian dummy (R-P), left pedestrian dummy (L-P), and right and left pedestrian dummies (RL-P). Regarding the gazing characteristics, there was no significant difference in the average total gaze time at each AOI between the two vehicles under different conditions, which suggests that the total gaze time was not affected by the vehicle type. All participants gazed at the pedestrian dummies in R-P, L-P, and RL-P. However, the average total gaze time at the right pedestrian dummy (0.63-0.72 s) in R-P was significantly shorter than that at the left pedestrian dummy (1.46-1.57 s) in L- P for both vehicles. The average vehicle speed at the entrance line to the intersection (L1) of the light-duty truck (16.8-18.2 km/h) was lower than that of the sedan (18.8-19.7 km/h). The average vehicle speed at the pedestrian crossing line (L0) of the light-duty truck (15.5-16.0 km/h) was lower than that of the sedan (16.0-17.8 km/h). There was no significant difference in the average vehicle speeds at L1 and L0 between them under any two conditions. We investigated the estimated time to collision (TTC), calculated from the distance on the vehicle traveling trajectory from the vehicle to the pedestrian crossing line and the vehicle speed at the moment when the drivers first gazed at the pedestrian dummies. The average TTC of the right pedestrian dummy in R-P for the sedan (3.5 s) was significantly shorter than that for the light-duty truck (4.0 s). Similarly, the average TTC of the left pedestrian dummy in L-P for the sedan (3.7 s) was significantly shorter than that for the light-duty truck (4.8 s). The driving characteristics obtained in this study may contribute to the development of advanced driver support systems, particularly for vehicles turning right at intersections.


Subject(s)
Accidents, Traffic , Automobile Driving , Pedestrians , Humans , Japan
6.
Water Res ; 206: 117735, 2021 Nov 01.
Article in English | MEDLINE | ID: mdl-34673461

ABSTRACT

Treatment of wastewater for potable reuse is increasingly becoming a suitable alternative water source to meet the growing urban water needs worldwide. Potable reuse requires reduction of enteric viruses to levels at which they do not pose a risk to human health. Advanced water treatment trains (e.g., microfiltration (MF), ultrafiltration (UF), reverse osmosis (RO), and ultraviolet light and advanced oxidation process (UV/AOP)) provide significant protection and reduce virus loads in highly treated final product waters. Even though viruses are a principal concern, the performance of virus removal by membrane processes is not easily determined. The objective of this study was to evaluate the applicability of Aichi virus (AiV), pepper mild mottle virus (PMMoV), cucumber green mottle mosaic virus (CGMMV), and cross-assembly phage (crAssphage) removal as possible process indicators for MF, UF, and RO. Virus log reduction values (LRVs) based on gene copies measured using molecular methods were determined for MF and UF. The median LRVs of all viruses obtained after MF and UF were 2.9 and 3.1, respectively. The LRVs of the proposed indicators were lower than those of human enteric viruses. The morphological and physicochemical difference among indicators was not found to affect LRVs. Therefore, all proposed indicator viruses were determined to be suitable candidates as process indicators for MF and UF. Regarding RO, most of the viruses measured in this study were undetectable in permeate. Only PMMoV and CGMMV were detected showing median LRVs of 2.8 and 2.5, respectively. PMMoV and CGMMV are recommended as good process indicators of physical virus removal for the overall water treatment process.


Subject(s)
Enterovirus , Tobamovirus , Water Purification , Humans , Ultrafiltration
7.
Asian J Pharm Sci ; 16(2): 253-262, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33995618

ABSTRACT

We presented a control strategy for tablet manufacturing processes based on continuous direct compression. The work was conducted by the experts of pharmaceutical companies, machine suppliers, academia, and regulatory authority in Japan. Among different items in the process, the component ratio and blended powder content were selected as the items requiring the control method specific to continuous manufacturing different from the conventional batch manufacturing. The control and management of the Loss in Weight (LIW) feeder were deemed the most important, and the Residence Time Distribution (RTD) model were regarded effective for setting the control range and for controlling of the LIW feeder. Based on these ideas, the concept of process control using RTD was summarized. The presented contents can serve as a solid fundament for adopting a new control method of continuous direct compression processes in and beyond the Japanese market.

8.
Accid Anal Prev ; 156: 106131, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33873133

ABSTRACT

The incidence of traffic accidents in Japan has been decreasing annually. Nineteen percent of all accidents involve bicycles, with 51 % of these accidents being at road crossing intersections. Therefore, to reduce the number of accidents, this study analyses driving and cycling characteristics and proposes suitable collisions prevention methods. First, the study measured traffic environment variables using video cameras at a target non-signalized intersection and analyzed the speed and time to intersection of bicycles and motor vehicles. Thus, 47 dangerous situations were observed via the video analysis, and most of these situations occurred when the vehicle's time to intersection ranged from 0.50 to 0.75 s and the bicycle's speed ranged from 2.0-3.0 m/s. Second, using the results of video camera analysis as experimental parameters (e.g., the speed and timing of the presence of the bicycle), this study conducted an experiment with a driving simulator to investigate the effect of warning drivers about the risk of collision. A driver support system was then utilized to provide acoustic and optical warnings to drivers. The experiments revealed that the motor vehicle time to the anticipated collision point (V-TTC) increased with the use of a driver support system. Significant differences between experiments with and without driver support systems were observed when the calculated time between the bicycle and the motor vehicle was 0.25 and 0.50 s. Therefore, when the calculated time was 0.25 and 0.50 s, a driver support system, indicating the presence of a bicycle, was effective in preventing an intersection collision.


Subject(s)
Automobile Driving , Bicycling , Accidents, Traffic/prevention & control , Humans , Japan , Motor Vehicles
9.
Stapp Car Crash J ; 65: 163-187, 2021 11.
Article in English | MEDLINE | ID: mdl-35512788

ABSTRACT

Vehicles that start moving from a stationary position can cause fatal traffic accidents involving pedestrians. Ultrasonic sensors installed in the vehicle front are an active technology designed to alert drivers to the presence of stationary objects such as rigid walls in front of their vehicles. However, the ability of such sensors to detect humans has not yet been established. Therefore, this study aims to ascertain whether these sensor systems can successfully detect humans. First, we conducted experiments using four vehicles equipped with ultrasonic sensor systems for vehicle-forward moving-off maneuvers and investigated the detection distances between the vehicles and a pipe (1 m long and having a diameter of 75 mm), child, adult female, or adult male. The detections of human volunteers were evaluated under two different conditions: front-facing and sidefacing toward the front of each vehicle. Front-facing is defined as the condition where the human faces the vehicle front, while side-facing is that where the side of the human faces it. For both the front-facing and side-facing conditions, the results indicated that the sensor-detection distances for a child were shorter than those for the pipe, whereas those for adults were less than or approximately equivalent to those for the pipe. These results revealed that ultrasonic sensor systems for vehicle-forward movingoff maneuvers can detect not only stationary objects but also humans, indicating that ultrasonic sensors installed in the vehicle front could possibly reduce the risk of vehicle-forward moving-off accidents involving pedestrians.


Subject(s)
Pedestrians , Accidents, Traffic , Adult , Child , Female , Humans , Male , Motor Vehicles , Ultrasonics
10.
Opt Lett ; 45(12): 3337-3339, 2020 Jun 15.
Article in English | MEDLINE | ID: mdl-32538977

ABSTRACT

We demonstrate a direct-modulation and direct-detection system with a back-to-back line rate of 411.6 (net bit rate of 337.5) Gb/s using a 65 GHz DFB+R laser. The O-band laser with a chirp parameter of 0.6 supports dispersion-tolerant transmissions up to 15 km without an optical amplifier.

11.
Stapp Car Crash J ; 64: 269-289, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33636007

ABSTRACT

This paper examines how vehicle backing technologies affect driver performance during backing maneuvers. We conducted experiments using sport utility vehicles (SUV) with four technological variations: a baseline vehicle (B-L), a vehicle equipped with a parking sensor (PS-V), a vehicle equipped with a backup camera (hereafter BC-V), and a vehicle equipped with both technologies (BCPS-V). Two reverse parking maneuvers were tested: backing straight and backing diagonally into a parking space. For each vehicle, we measured the parameters of the driver's gaze, vehicle speed, the distance between the stopped vehicle and an object behind it, and the presence or absence of contact with the object. Fifteen drivers participated in the experiment. For backing straight, the B-L and PS-V drivers gazed at the driver-side mirror the longest; BC-V and BCPS-V drivers gazed at the monitor the longest. There was no significant difference in maximum speed among the four backing technology conditions. The PS-V was the farthest from the object when stopped, followed by the BCPS-V, the BC-V, and the B-L. Regarding the rate of noncontact, the BCPS-V ranked highest (67%, 95% confidence of interval [CI] [38%, 88%]), followed by the PS-V (60%, 95% CI [32%, 84%]), the BC-V (53%, 95% CI [27%, 79%]), and the B-L (20%, 95% CI [4%, 48%]). For backing diagonally, the B-L and PS-V drivers gazed at the passenger-side mirror the longest; BC-V and BCPS-V drivers gazed at the monitor the longest. The vehicles' maximum speed showed no significant difference between the four backing technologies. However, the presence of backing technologies significantly reduced the vehicle speed at the object location. Once stopped, the BCPS-V had the longest distance from the object behind it, followed by the PS-V, the BC-V, and the B-L. The rate of non-contact was the highest for the PS-V (73%, 95% CI [45%, 92%]), followed by the BCPS-V (67%, 95% CI [38%, 88%]), the BC-V (60%, 95% CI [32%, 84%]), and the B-L (20%, 95% CI [4%, 48%]). These results indicate that the backing technologies in this study reduced the probability of direct impact with objects situated behind the vehicles. However, focusing on backing diagonally, which requires more complicated driving, vehicles equipped with a sonar backing system appear, in this study, to perform better in terms of stopping distance than those that did not have sonar.


Subject(s)
Accidents, Traffic , Automobile Driving , Automobiles , Humans , Motor Vehicles , Technology
12.
Traffic Inj Prev ; 20(sup1): S1-S6, 2019.
Article in English | MEDLINE | ID: mdl-31381444

ABSTRACT

Objective: This study aimed to investigate the situational characteristics of fatal pedestrian accidents involving vehicles traveling at low speeds in Japan. We focused on vehicles with 4 or more wheels. Such characteristics included daytime or nighttime conditions, road type, vehicle behaviors preceding the accident, and vehicle impact locations. Methods: Pedestrian fatality data on vehicle-pedestrian accidents were obtained from the Institute for Traffic Accident Research and Data Analysis of Japan (ITARDA) from 2005 to 2014. Nine vehicle classifications were considered: Trucks with gross vehicle weight (GVW) ≥7.5 tons and <7.5 tons, buses, box vans, minivans, sport utility vehicles (SUVs), sedans, light passenger cars (LPCs), and light cargo vans (LCVs). We compared the situational daytime or nighttime conditions, road type, vehicle behaviors preceding the accident, and vehicle impact locations for accident-involved vehicles traveling at low and higher speeds across all vehicle types. Results: The results indicate that pedestrian fatalities involving vehicles traveling at low speeds occurred more often under daytime conditions across all vehicle types. At signalized intersections, the relative proportions of pedestrian fatalities were significantly higher when vehicles were traveling at low speed, except when the accidents involved box vans or SUVs. Similarly, when vehicles turned right, the relative proportions of pedestrian fatalities were significantly higher when vehicles traveling at low speed were involved across all vehicle types. In terms of the frontal right vehicle impact location, the relative proportions of pedestrian fatalities were significantly higher when trucks with GVW ≥7.5 tons or <7.5 tons, sedans, or LCVs traveling at low speed were involved. Conclusions: The situational characteristics of fatal pedestrian accidents involving vehicles traveling at low speeds identified in this study can guide targeted development of new traffic safety regulations or technologies specific to vehicle-pedestrian interactions at low vehicle travel speeds (i.e., driver alert devices or automated emergency braking systems). Ultimately, these developments can improve pedestrian safety by reducing the frequency or severity of vehicle-pedestrian accidents for vehicles turning right at intersections and/or reducing the number of resultant pedestrian fatalities.


Subject(s)
Accidents, Traffic/mortality , Deceleration , Motor Vehicles , Pedestrians , Accidents, Traffic/statistics & numerical data , Humans , Japan/epidemiology
13.
Chem Pharm Bull (Tokyo) ; 67(8): 801-809, 2019.
Article in English | MEDLINE | ID: mdl-31366829

ABSTRACT

Granules prepared by a continuous twin screw granulator (TSG) were analyzed by X-ray micro-computed tomography (X-ray µCT) and the relationships between porosity of granules and granule properties were investigated. A model formulation containing ibuprofen, lactose monohydrate, microcrystalline cellulose, and hydroxypropyl cellulose was used. The porosity of granules was measured by X-ray µCT and mercury porosimetry. The data sets obtained by both methods showed linear correlation despite different values, which were attributed to the resolution of X-ray µCT and a low-signal-to-noise ratio of the original cross-sectional images. The porosity of granules measured by X-ray µCT decreased from 11-14 to 6-7% as liquid-to-solid ratio (L/S) increased, while the standard deviation (S.D.) of the porosity of individual granules decreased from 4-5 to 2%. L/S affected the porosity of granules. By contrast, the effect of screw speed was not significant. Pressure transmission, G, which indicates the liquid dispersion in wet kneaded masses, increased as the porosity of granules and the S.D. decreased. The cross-sectional images showed that granules were densified as L/S increased. Based on these results, the effect of L/S on the porosity of granules can be explained by liquid dispersion and densification of the wet granules. The porosity of granules measured by X-ray µCT showed good linear correlation with friability and drug dissolution rate (R2 = 0.9107 and 0.8834, respectively). This study revealed that the drug dissolution rate was regulated by a disintegration step in which the porosity of granules plays an important role.


Subject(s)
Bone Screws , Technology, Pharmaceutical , X-Ray Microtomography , Particle Size , Porosity , Surface Properties , X-Rays
14.
Stapp Car Crash J ; 63: 343-358, 2019 Nov.
Article in English | MEDLINE | ID: mdl-32311064

ABSTRACT

Ultrasonic parking sensors are an active technology designed to alert drivers to the presence of objects behind their vehicle but not the presence of a human. The purpose of this study was therefore to ascertain if these sensor systems can successfully detect a human subject. We accordingly conducted experiments using four vehicles equipped with both rear-facing center and corner ultrasonic parking sensor systems to determine the detection distance between the vehicle and a 1-m tall, 75-mm diameter pipe, a child, an adult woman, and an adult man. The detection of human subjects was evaluated under front-facing and side-facing conditions behind each vehicle. The results indicate that for a front-facing and side-facing child, the center sensor detection distances were 50-84% and 32-64%, respectively, shorter than that of the pipe. For front-facing and side-facing adults, the center sensor detection distances were just less than or roughly equivalent to that of the pipe at 89-102% and 78-97%, respectively. A similar trend was seen for the corner sensors. Notably, under the side-facing condition, the sensor detection distances were slightly shorter for all subjects than under the front-facing condition. These results reveal that ultrasonic parking sensor systems can not only detect objects but also humans, indicating that ultrasonic sensors are an available countermeasure to prevent backover accidents involving pedestrians. To address the shorter detection distance of children, a combination of ultrasonic parking sensors with other systems, such as backup cameras, may be more effective for avoiding backover collisions.


Subject(s)
Accident Prevention , Accidents, Traffic , Pedestrians , Ultrasonics , Adult , Automobiles , Child , Female , Humans , Male
16.
Traffic Inj Prev ; 19(7): 773-777, 2018.
Article in English | MEDLINE | ID: mdl-30001152

ABSTRACT

OBJECTIVE: To assess the effect of wearing a bicycle helmet using an adult headform in terms of the head injury criterion (HIC) when the frontal and lateral parts of the helmet impact a vehicle body and also when the frontal part of the helmet impacts the road surface. METHODS: The adult headform was made to impact the hood, windscreen, roof top, and roof side rail of a vehicle body at an impact velocity of 35 km/h, which is a common head-to-vehicle impact velocity in real-world cyclist-vehicle collisions, in which the vehicle impacts the cyclist at 40 km/h. For the road surface impact experiments, we set a drop height of 1.5 m (impact velocity of 20 km/h). RESULTS: Helmet usage helped to reduce the HIC when the frontal and lateral parts of the helmet impacted vehicle parts other than the hood. The HIC reduction for the frontal impact was greater than that for the lateral impact. Moreover, the higher the stiffness index of the vehicle structure, the greater was the HIC reduction. However, helmet usage was ineffective for reducing skull fracture risk (HIC 2558) when the lateral part of the helmet impacted stiffer parts of the vehicle, such as the roof side rail close to the B-pillar. Helmet usage helped to reduce the HIC by 91% when the frontal part of the helmet impacted the road surface. CONCLUSIONS: Wearing a helmet reduces skull fracture risk when the frontal and lateral parts of the helmet impact vehicle parts (excluding the hood) at 35 km/h and the road surface at 20 km/h. However, when the lateral part of the helmet impacts the B-pillar, the helmet cannot effectively reduce the skull fracture risk at these real-world velocities.


Subject(s)
Bicycling/injuries , Craniocerebral Trauma/prevention & control , Head Protective Devices , Accidents, Traffic , Adult , Craniocerebral Trauma/etiology , Equipment Design , Equipment Safety/methods , Humans , Materials Testing/methods
17.
Sensors (Basel) ; 18(2)2018 Feb 20.
Article in English | MEDLINE | ID: mdl-29461473

ABSTRACT

The paper presents an emerging issue of fine-grained pedestrian action recognition that induces an advanced pre-crush safety to estimate a pedestrian intention in advance. The fine-grained pedestrian actions include visually slight differences (e.g., walking straight and crossing), which are difficult to distinguish from each other. It is believed that the fine-grained action recognition induces a pedestrian intention estimation for a helpful advanced driver-assistance systems (ADAS). The following difficulties have been studied to achieve a fine-grained and accurate pedestrian action recognition: (i) In order to analyze the fine-grained motion of a pedestrian appearance in the vehicle-mounted drive recorder, a method to describe subtle change of motion characteristics occurring in a short time is necessary; (ii) even when the background moves greatly due to the driving of the vehicle, it is necessary to detect changes in subtle motion of the pedestrian; (iii) the collection of large-scale fine-grained actions is very difficult, and therefore a relatively small database should be focused. We find out how to learn an effective recognition model with only a small-scale database. Here, we have thoroughly evaluated several types of configurations to explore an effective approach in fine-grained pedestrian action recognition without a large-scale database. Moreover, two different datasets have been collected in order to raise the issue. Finally, our proposal attained 91.01% on National Traffic Science and Environment Laboratory database (NTSEL) and 53.23% on the near-miss driving recorder database (NDRDB). The paper has improved +8.28% and +6.53% from baseline two-stream fusion convnets.


Subject(s)
Automobile Driving , Databases, Factual , Pedestrians , Safety , Accidents, Traffic , Humans , Time Factors , Video Recording , Walking
18.
Stapp Car Crash J ; 62: 393-413, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30609002

ABSTRACT

Accident emergency calling systems (AECSs) are signaled by the deployment of airbags, which causes them to automatically emit information providing the location of the accident site to a public service answering party (PSAP). In some realworld accidents, airbags have failed to deploy. This study clarifies the factors that influence the nondeployment of front airbags in vehicle-vehicle collisions, investigating nondeployment of the driver-side front airbags in sedans and light passenger cars (LPCs) from Japanese accident data. The component rates of deployment for front airbags tend to be higher than those of nondeployment at higher values of pseudo-ΔV in vehicle-vehicle frontal impacts. For both sedans and LPCs, the transition zones between nondeployment and deployment of the front airbag occur at pseudo-ΔV values of 30-50 km/h (ΔV ≈ 21-35 km/h). For mutual impact locations where sedans and LPCs impact opponent vehicles at pseudo-ΔV ≥ 40 km/h (ΔV ≈ 28 km/h) in frontal impacts, the component rate of front airbag nondeployment is higher than that of deployment in right-to-right impacts. The results indicate that factors influencing front airbag nondeployment in vehicle-vehicle collisions are ΔV, impact offset configuration, and crossing angle. Considering front airbag nondeployment in real-world accidents, AECSs should have other functions, such as a manual button, to emit information in addition to automatic emission via airbag signaling.


Subject(s)
Accidents, Traffic , Air Bags , Air Bags/statistics & numerical data , Automobiles , Japan
19.
Traffic Inj Prev ; 19(1): 60-65, 2018 01 02.
Article in English | MEDLINE | ID: mdl-28581829

ABSTRACT

OBJECTIVE: The purpose of this study was to identify and better understand the features of fatal injuries in cyclists aged 75 years and over involved in collisions with either hood- or van-type vehicles. METHODS: This study investigated the fatal injuries of cyclists aged 75 years old and over by analyzing accident data. We focused on the body regions to which the fatal injury occurred using vehicle-bicycle accident data from the Institute for Traffic Accident Research and Data Analysis (ITARDA) in Japan. Using data from 2009 to 2013, we examined the frequency of fatally injured body region by gender, age, and actual vehicle travel speed. We investigated any significant differences in distributions of fatal injuries by body region for cyclists aged 75 years and over using chi-square tests to compare with cyclists in other age groups. We also investigated the cause of fatal head injuries, such as impact with a road surface or vehicle. RESULTS: The results indicated that head injuries were the most common cause of fatalities among the study group. At low vehicle travel speeds for both hood- and van-type vehicles, fatalities were most likely to be the result of head impacts against the road surface. The percentage of fatalities following hip injuries was significantly higher for cyclists aged 75 years and over than for those aged 65-74 or 13-59 in impacts with hood-type vehicles. It was also higher for women than men in the over-75 age group in impacts with these vehicles. CONCLUSIONS: For cyclists aged 75 years and over, wearing a helmet may be helpful to prevent head injuries in vehicle-to-cyclist accidents. It may also be helpful to introduce some safety measures to prevent hip injuries, given the higher level of fatalities following hip injury among all cyclists aged 75 and over, particularly women.


Subject(s)
Accidents, Traffic/mortality , Accidents, Traffic/statistics & numerical data , Bicycling/injuries , Wounds and Injuries/mortality , Adolescent , Adult , Age Distribution , Aged , Craniocerebral Trauma/etiology , Craniocerebral Trauma/mortality , Female , Head Protective Devices/statistics & numerical data , Hip Injuries/etiology , Hip Injuries/mortality , Humans , Japan/epidemiology , Male , Middle Aged , Wounds and Injuries/etiology , Young Adult
20.
Stapp Car Crash J ; 61: 53-65, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29394435

ABSTRACT

This study aims to clarify the relation between axonal deformation and the onset of axonal injury. Firstly, to examine the influence of strain rate on the threshold for axonal injury, cultured neurons were subjected to 12 types of stretching (strains were 0.10, 0.15, and 0.20 and strain rates were 10, 30, 50, and 70 s-1). The formation of axonal swellings and bulbs increased significantly at strain rates of 50 and 30 s-1 with strains of 0.15 and 0.20, respectively, even though those formations did not depend on strain rates in cultures exposed to a strain of 0.10. Then, to examine the influence of the strain along an axon on axonal injury, swellings were measured at every axonal angle in the stretching direction. The axons that were parallel to stretching direction were injured the most. Finally, we proposed an experimental model that subjected an axon to more accurate strain. This model observed the process of axonal injury formation by detecting the same neuron before and after stretching. These results suggest that the strain-rate dependency of axonal tolerance is induced by a higher magnitude of loading strain and an experiment focusing on axonal strain is required for obtaining more detailed injury criteria for an axon.


Subject(s)
Axons/physiology , Brain Injuries, Traumatic/physiopathology , Diffuse Axonal Injury/physiopathology , Stress, Mechanical , Animals , Cells, Cultured , Mice , Mouse Embryonic Stem Cells , Neural Stem Cells , Neurons/physiology
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