1,142 research outputs found

    Estimating Autonomous Vehicle Localization Error Using 2D Geographic Information

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    Accurately and precisely knowing the location of the vehicle is a critical requirement for safe and successful autonomous driving. Recent studies suggest that error for map-based localization methods are tightly coupled with the surrounding environment. Considering this relationship, it is therefore possible to estimate localization error by quantifying the representation and layout of real-world phenomena. To date, existing work on estimating localization error have been limited to using self-collected 3D point cloud maps. This paper investigates the use of pre-existing 2D geographic information datasets as a proxy to estimate autonomous vehicle localization error. Seven map evaluation factors were defined for 2D geographic information in a vector format, and random forest regression was used to estimate localization error for five experiment paths in Shinjuku, Tokyo. In the best model, the results show that it is possible to estimate autonomous vehicle localization error with 69.8% of predictions within 2.5 cm and 87.4% within 5 cm

    Evaluating the Capability of OpenStreetMap for Estimating Vehicle Localization Error

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    Accurate localization is an important part of successful autonomous driving. Recent studies suggest that when using map-based localization methods, the representation and layout of real-world phenomena within the prebuilt map is a source of error. To date, the investigations have been limited to 3D point clouds and normal distribution (ND) maps. This paper explores the potential of using OpenStreetMap (OSM) as a proxy to estimate vehicle localization error. Specifically, the experiment uses random forest regression to estimate mean 3D localization error from map matching using LiDAR scans and ND maps. Six map evaluation factors were defined for 2D geographic information in a vector format. Initial results for a 1.2 km path in Shinjuku, Tokyo, show that vehicle localization error can be estimated with 56.3% model prediction accuracy with two existing OSM data layers only. When OSM data quality issues (inconsistency and completeness) were addressed, the model prediction accuracy was improved to 73.1%

    On Ultrasmall Silicate Grains in the Diffuse Interstellar Medium

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    The abundance of both amorphous and crystalline silicates in very small grains is limited by the fact that the 10 micron silicate emission feature is not detected in the diffuse ISM. On the basis of the observed IR emission spectrum for the diffuse ISM, the observed ultraviolet extinction curve, and the 10 micron silicate absorption profile, we obtain upper limits on the abundances of ultrasmall (a < 15 Angstrom) amorphous and crystalline silicate grains. Contrary to previous work, as much as ~20% of interstellar Si could be in a < 15 Angstrom silicate grains without violating observational constraints. Not more than ~5% of the Si can be in crystalline silicates (of any size).Comment: Submitted to ApJ Letters, 11 pages, 4 figures, Late

    A Case of Mycobacterial Skin Disease Caused by Mycobacterium peregrinum, and a Review of Cutaneous Infection

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    An 83-year-old Japanese man presented with a 2-month history of symptomatic nodules on the left hand. He was not in an immunocompromised condition and reported no causal events. A biopsy specimen demonstrated granulomatous tissue with mixed cell infiltration consisting of neutrophils, histiocytes, lymphocytes, and multinuclear giant cells. No bacillus was detected by PAS, acid-fast stain, immunofluorescent stain or polymerase chain reaction analysis. The isolate was found to be a rapidly growing mycobacterium after 4 weeks of incubation at 25°C on an Ogawa egg slant. Mycobacterium peregrinum was isolated by DNA-DNA hybridization analysis, 16S rRNA gene sequence, and by its production of 3-day arylsulfatase. The patient received 200 mg oral minocycline for 28 weeks. The lesion disappeared after 10 weeks of this treatment

    Significance of chemokine receptor expression in aggressive NK cell leukemia

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    ArticleLEUKEMIA. 19(7): 1169-1174 (2005)journal articl

    COVID-19-Related Factors Delaying Dental Visits of Workers in Japan

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    BACKGROUND: The aim of this research was to investigate the factors associated with postponing dental attendance amongst Japanese workers during the coronavirus disease 2019 (COVID-19) pandemic. METHODS: We conducted an internet-based survey in Japan from November 24 to 29, 2021. The participants were selected from people registered with an online research company. The inclusion criteria for this study were full-time or part-time workers aged 20 to 69 years. Participants filled out a questionnaire about their oral health, behaviour, and working conditions. RESULTS: A total of 1840 participants were included in the analysis. Three hundred ninety-eight participants (21.5%) answered that they postponed dental attendance due to COVID-19. Multiple logistic regression showed that women were more likely to postpone dental attendance (odds ratio [OR], 1.74; 95% confidence interval, 1.33–2.26). Moreover, employment status, household income, changes in income, working at home, interdental cleaning device use, regular dental attendance, awareness of untreated teeth, and dental pain were also associated with postponing dental attendance. The results of decision tree analysis showed that regular dental attenders with dental pain were the most likely to postpone dental attendance. CONCLUSIONS: The characteristics of postponed dental visits for Japanese workers differ depending on whether one is a regular dental attender or not. Amongst regular dental attenders, worsening oral health due to interruptions in dental attendance is concerning. Meanwhile, untreated teeth might be neglected amongst nonregular dental attenders. Preventing patients from refraining from dental attendance, regardless of whether or not they are regular dental attenders, is important during the COVID-19 pandemic

    Comparison between esophageal and intestinal temperature responses to upper-limb exercise in individuals with spinal cord injury

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    Objective: Individuals with spinal cord injuries (SCI) may present with impaired sympathetic control over thermoregulatory responses to environmental and exercise stressors, which can impact regional core temperature (Tcore) measurement. The purpose of this study was to investigate whether regional differences in Tcore responses exist during exercise in individuals with SCI. Setting: Rehabilitation centre in Wakayama, Japan. Methods: We recruited 12 men with motor-complete SCI (7 tetraplegia, 5 paraplegia) and 5 able-bodied controls to complete a 30-minute bout of arm-cycling exercise at 50% V̇ O2peak. Tcore was estimated using telemetric pills (intestinal temperature; Tint) and esophageal probes (Teso). Heat storage was calculated from baseline to 15 and 30 minutes of exercise. Results: At 15 minutes of exercise, elevations in Teso (Δ0.39±0.22°C; P<0.05), but not Tint (Δ0.04±0.18°C; P=0.09), were observed in able-bodied men. At 30 minutes of exercise, men with paraplegia and able-bodied men both exhibited increases in Teso (paraplegia: Δ0.56±0.30°C, P<0.05; able-bodied men: Δ0.60±0.31°C, P<0.05) and Tint (paraplegia: Δ0.38±0.33°C, P<0.05; able-bodied men: Δ0.30±0.30°C, P<0.05). Teso began rising 7.2 min earlier than Tint (pooled, P<0.01). Heat storage estimated by Teso was greater than heat storage estimated by Tint at 15 minutes (P=0.02) and 30 minutes (P=0.03) in men with paraplegia. No elevations in Teso, Tint, or heat storage were observed in men with tetraplegia. Conclusions: While not interchangeable, both Teso and Tint are sensitive to elevations in Tcore during arm-cycling exercise in men with paraplegia, although Teso may have superior sensitivity to capture temperature information earlier during exercise
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