1,321 research outputs found
Characteristics of Errors in Open and Closed Trilateration Nets
Distance measurements have been more and more easy and accurate to carry out, and it is expected that distance mesurements may provide rather accurate results than angle measurements. Under these circumstances, caracteritics of errors in typical trilateration nets are investigated. The nets investigated are as follows: From single row of chains to pranimetrically extended nets in figure, open and closed networks with respect to external constraint, and with and without as to internal constraint. Computations are performed by use of the method of condition equations, and behaviours of error propagation and errors of coordinates of stations in the nets are shown in case of typical nets. For example, effects for decrease in error by composing a double row of chains and by enforcing external constraints are explained
A Prospective Study of Long-term Outcomes in Female Patients with Nonalcoholic Steatohepatitis Using Age- and Body Mass Index-matched Cohorts
In patients with nonalcoholic steatohepatitis (NASH), the prevalence of cirrhosis is higher among women than men, and hepatocellular carcinoma (HCC) develops mainly in the cirrhotic stage among women. However, the long-term outcomes in female patients with NASH have not been fully elucidated, and age, gender and BMI were not simultaneously adjusted in previous studies on the prognosis of NASH. To elucidate the outcomes in female patients with NASH, we prospectively compared NASH patients with advanced fibrosis (advanced NASH) with hepatitis C virus-related advanced fibrosis (advanced CHC) patients and NASH patients with mild fibrosis (mild NASH) using study cohorts that were adjusted for body mass index (BMI) in addition to age. The median follow-up period was 92.5 months. Liver-related complication-free survival was significantly reduced in the advanced NASH group compared to the mild NASH group. No liver-related complications developed in the mild NASH group. The overall survival, liver-related complication- and cardiovascular/cerebrovascular disease-free survival were not significantly different between the advanced NASH and CHC groups. Female patients with NASH and advanced fibrosis may have a less favorable prognosis for liver-related complications than the matched cohorts with NASH and mild fibrosis, but may have a similar prognosis to the matched cohorts with CHC
Conservative Estimation of Perception Relevance of Dynamic Objects for Safe Trajectories in Automotive Scenarios
Having efficient testing strategies is a core challenge that needs to be
overcome for the release of automated driving. This necessitates clear
requirements as well as suitable methods for testing. In this work, the
requirements for perception modules are considered with respect to relevance.
The concept of relevance currently remains insufficiently defined and
specified. In this paper, we propose a novel methodology to overcome this
challenge by exemplary application to collision safety in the highway domain.
Using this general system and use case specification, a corresponding concept
for relevance is derived. Irrelevant objects are thus defined as objects which
do not limit the set of safe actions available to the ego vehicle under
consideration of all uncertainties. As an initial step, the use case is
decomposed into functional scenarios with respect to collision relevance. For
each functional scenario, possible actions of both the ego vehicle and any
other dynamic object are formalized as equations. This set of possible actions
is constrained by traffic rules, yielding relevance criteria. As a result, we
present a conservative estimation which dynamic objects are relevant for
perception and need to be considered for a complete evaluation. The estimation
provides requirements which are applicable for offline testing and validation
of perception components. A visualization is presented for examples from the
highD dataset, showing the plausibility of the results. Finally, a possibility
for a future validation of the presented relevance concept is outlined
SURE-Val: Safe Urban Relevance Extension and Validation
To evaluate perception components of an automated driving system, it is
necessary to define the relevant objects. While the urban domain is popular
among perception datasets, relevance is insufficiently specified for this
domain. Therefore, this work adopts an existing method to define relevance in
the highway domain and expands it to the urban domain. While different
conceptualizations and definitions of relevance are present in literature,
there is a lack of methods to validate these definitions. Therefore, this work
presents a novel relevance validation method leveraging a motion prediction
component. The validation leverages the idea that removing irrelevant objects
should not influence a prediction component which reflects human driving
behavior. The influence on the prediction is quantified by considering the
statistical distribution of prediction performance across a large-scale
dataset. The validation procedure is verified using criteria specifically
designed to exclude relevant objects. The validation method is successfully
applied to the relevance criteria from this work, thus supporting their
validity.Comment: Accepted at Uni-DAS e.V. Workshop Fahrerassistenz und automatisiertes
Fahre
Design of characteristics of optical filter set for prediction and visualization of fat content in raw beef cuts
超音波断層法を用いた嚥下運動評価法
The aim of this study is to develop an index to assess swallowing function by ultrasonography in order to evaluate the relationship between movements of the hyoid bone and the larynx while swallowing water. Forty-two younger participants (mean age, 20.3 ± 3.4 years) and 42 older participants (mean age, 75.1 ± 10.6 years) with normal swallowing function were included in the study. Movements of the hyoid bone and the larynx while swallowing 5 mL of water were observed using ultrasonography. Two-dimensional distances from the starting points of the hyoid bone and the larynx to their points of maximum movement were measured as displacements. The hyoid bone–laryngeal motion ratio was defined as the hyoid bone displacement divided by the laryngeal displacement. Parameters were compared among four groups: younger male, younger female, older male, and older female. The hyoid bone displacement differed significantly between the younger and older groups, and the laryngeal displacement differed significantly between age groups and sexes. The hyoid bone–laryngeal motion ratio was not significantly correlated with age, height, or body weight, and did not show a significant difference between the four groups. Thus, the hyoid bone–laryngeal motion ratio is an index that evaluates swallowing movement and is independent of physique and physiological changes associated with aging
Global Radiation-Magnetohydrodynamic Simulations of Black Hole Accretion Flow and Outflow: Unified Model of Three States
Black-hole accretion systems are known to possess several distinct modes (or
spectral states), such as low/hard state, high/soft state, and so on. Since the
dynamics of the corresponding flows is distinct, theoretical models were
separately discussed for each state. We here propose a unified model based on
our new, global, two-dimensional radiation-magnetohydrodynamic simulations. By
controlling a density normalization we could for the first time reproduce three
distinct modes of accretion flow and outflow with one numerical code. When the
density is large (model A), a geometrically thick, very luminous disk forms, in
which photon trapping takes place. When the density is moderate (model B), the
accreting gas can effectively cool by emitting radiation, thus generating a
thin disk, i.e., the soft-state disk. When the density is too low for radiative
cooling to be important (model C), a disk becomes hot, thick, and faint; i.e.,
the hard-state disk. The magnetic energy is amplified within the disk up to
about twice, 30%, and 20% of the gas energy in models A, B, and C,
respectively. Notably, the disk outflows with helical magnetic fields, which
are driven either by radiation pressure force or magnetic pressure force, are
ubiquitous in any accretion modes. Finally, our simulations are consistent with
the phenomenological alpha-viscosity prescription, that is, the disk viscosity
is proportional to the pressure.Comment: 5 pages, 2 figures, accepted for publication in PASJ Letter
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