It is anticipated that current and future preventive therapies will likely be more effective in the early stages of dementia, when everyday functioning is not affected. Accordingly the early ...identification of people at risk is particularly important. In most cases, when subjects visit an expert and are examined using neuropsychological tests, the disease has already been developed. Contrary to this cognitive games are played by healthy, well functioning elderly people, subjects who should be monitored for early signs. Further advantages of cognitive games are their accessibility and their cost-effectiveness.
The aim of the investigation was to show that computer games can help to identify those who are at risk. In order to validate games analysis was completed which measured the correlations between results of the 'Find the Pairs' memory game and the volumes of the temporal brain regions previously found to be good predictors of later cognitive decline.
34 healthy elderly subjects were enrolled in the study. The volume of the cerebral structures was measured by MRI. Cortical reconstruction and volumetric segmentation were performed by Freesurfer.
There was a correlation between the number of attempts and the time required to complete the memory game and the volume of the entorhinal cortex, the temporal pole, and the hippocampus. There was also a correlation between the results of the Paired Associates Learning (PAL) test and the memory game.
The results gathered support the initial hypothesis that healthy elderly subjects achieving lower scores in the memory game have increased level of atrophy in the temporal brain structures and showed a decreased performance in the PAL test. Based on these results it can be concluded that memory games may be useful in early screening for cognitive decline.
Accuracy is an important factor in air traffic management which is why high requirements are necessary for each navigation system. The aim of this article is to describe the principles of the RelNav ...system and telemetry and their accuracy. We present the algorithms of the relative navigation system, which could be used for air traffic control in the case of the unavailability of satellite navigation system signals. This article sums up the different positioning methods, and deals with the accuracy of the relative navigation system (RelNav). Furthermore, the article considers the factors that influence the positioning accuracy. For this task, a computer simulation was created to evaluate the accuracy of the telemetric method. Next, we discuss the principles of telemetry and algorithms for calculating the position of the flying object (FO).
The article is devoted to process mapping and the design of a process map of the air transport process using available open-source online software/tools. The air transport process is a complex ...process that requires mutual coordination of individual activities to meet the process's objectives. At the input of this process are the requirements of the passenger, which enter the provision of the flight, and at the output is the measurement of customer satisfaction. Processes usually have duplication and inefficiencies, that can be effectively corrected once the process is appropriately documented. The process map provides a holistic view of the processes, describes their relationships, stakeholders involved and clearly explains them. At the same time, it enables the subsequent modification of the process, which is based on the needs of the air carrier and the fulfilment of the requirements of the customer. There is currently very little research on mapping the air transport process, and such a process map is a new perspective.
The article aims to support the Safety Management System’s implementation in the Visegrad Four (V4) countries by introducing supporting documentation at the national level or national legislation. ...The research subjects are the V4 countries (Poland, Hungary, the Czech Republic, Slovakia), where 39 air carriers operate. Safety management in today’s world is already necessary, yet introducing a Safety Management System (SMS) is voluntary in many areas, including some transport modes. In air transport, it is mandatory, and the general principles and guidelines of this system are set out in the International Civil Aviation Organization (ICAO), which has issued several regulations and recommendations. The lists of ICAO standards and essential translations can be considered a minimum, which is also approached by different authorities. The article points out the primary differences in SMS in individual V4 countries and presents which country provides the strongest support in implementing this system.
Presented work is primarily oriented on the experimental verification of the influence of fatigue on the psychological condition of the flying personnel, using psychological and performance tests. ...For the evaluation of a pilot performance, the 24 hours experiment was conducted. In total, eight subjects participated in the experimental measurements. Eight participants went through several tests, including simulator flights, to investigate the effects of the fatigue on the results of psychological measurements. Measurements included workload evaluation, using NASA task load evaluation concept and performance testing, using the so-called OR-test. Significant statistical differences between measurements performed during 24 hours were not found in the case of NASA task load Scores. In the case of OR-test, Friedman ANOVA and subsequent post-hoc analysis show that the greatest decrease in performance was observed in approximately 22 hours of wakefulness, i.e. approximately in half of the measuring process. The concept of 24-hour measurements for the quantification of fatigue is not commonly used yet as well as objectivization using performance testing. As the apparent effect of fatigue is mainly on performance testing results, it can be argued that this work could serve as a basis for further studies on fatigue. Also, it could serve as a support for introducing new pilots' psychological testing procedures in the future, which could contribute to current efforts to improve aviation safety.
Context.
On 2022 October 9 the brightest gamma-ray burst (GRB) ever observed lit up the high-energy sky. It was detected by a multitude of instruments, attracting the close attention of the GRB ...community, and saturated many detectors.
Aims.
GRBAlpha, a nano-satellite with a form factor of a 1U CubeSat, detected this extraordinarily bright long-duration GRB, GRB 221009A, without saturation but affected by pile-up. We present light curves of the prompt emission in 13 energy bands, from 80 keV to 950 keV, and performed a spectral analysis to calculate the peak flux and peak isotropic-equivalent luminosity.
Methods.
Since the satellite’s attitude information is not available for the time of this GRB, more than 200 incident directions were probed in order to find the median luminosity and its systematic uncertainty.
Results.
We find that the peak flux in the 80 − 800 keV range (observer frame) was
F
ph
p
= 1300
−200
+1200
ph cm
−2
s
−1
, or
F
erg
p
= 5.7
−0.7
+3.7
× 10
−4
erg cm
−2
s
−1
, and the fluence in the same energy range of the first GRB episode, which lasted 300 s and was observable by GRBAlpha, was
S
= 2.2
−0.3
+1.4
× 10
−2
erg cm
−2
, or
S
bol
= 4.9
−0.5
+0.8
× 10
−2
erg cm
−2
for the extrapolated range of 0.9 − 8690 keV. We infer the isotropic-equivalent released energy of the first GRB episode to be
E
iso
bol
= 2.8
−0.5
+0.8
× 10
54
erg in the 1 − 10 000 keV band (rest frame at
z
= 0.15). The peak isotropic-equivalent luminosity in the 92 − 920 keV range (rest frame) was
L
iso
p
= 3.7
−0.5
+2.5
× 10
52
erg s
−1
, and the bolometric peak isotropic-equivalent luminosity was
L
iso
p,bol
= 8.4
−1.5
+2.5
× 10
52
erg s
−1
(4 s scale) in the 1 − 10 000 keV range (rest frame). The peak emitted energy is
E
p
∗
=
E
p
(1+
z
)
= 1120 ± 470 keV. Our measurement of
L
iso
p,bol
is consistent with the Yonetoku relation. It is possible that, due to the spectral evolution of this GRB and the orientation of GRBAlpha at the peak time, the true values of peak flux, fluence,
L
iso
, and
E
iso
are even higher.
Aims. Since it launched on 22 March 2021, the 1U-sized CubeSat GRBAlpha operates and collects scientific data on high-energy transients, making it the smallest astrophysical space observatory to ...date. GRBAlpha is an in-orbit demonstration of a gamma-ray burst (GRB) detector concept suitably small to fit into a standard 1U volume. As was demonstrated in a companion paper, GRBAlpha adds significant value to the scientific community with accurate characterization of bright GRBs, including the recent outstanding event of GRB 221009A. Methods. The GRB detector is a 75 × 75 × 5 mm CsI(Tl) scintillator wrapped in a reflective foil (ESR) read out by an array of SiPM detectors, multi-pixel photon counters by Hamamatsu, driven by two separate redundant units. To further protect the scintillator block from sunlight and protect the SiPM detectors from particle radiation, we applied a multi-layer structure of Tedlar wrapping, anodized aluminium casing, and a lead-alloy shielding on one edge of the assembly. The setup allows observations of gamma radiation within the energy range of 70–890 keV with an energy resolution of ~30%. Results. Here, we summarize the system design of the GRBAlpha mission, including the electronics and software components of the detector, some aspects of the platform, and the current semi-autonomous operations. In addition, details are given about the raw data products and telemetry in order to encourage the community to expand the receiver network for our initiatives with GRBAlpha and related experiments.
The discrepancy between stored energies measured by calorimetry and residual electrical resistivity, and calculated from dislocation densities measured either by transmission electron microscopy or ...X-ray line broadening in copper, is interpreted in terms of vacancies produced during plastic deformation. The presence of excess vacancies is further substantiated by concomitant measurements of residual electrical resistivity. Diffuse X-ray scattering is correlated with excess vacancy concentrations in the grain interior and grain boundary regions in polycrystalline copper. Grain boundaries are suggested to be the main sites for vacancy storage probably in the form of voids or free volume. This would support the concept that grain boundaries are distorted regions with considerable fractions of free volume. The vacancy storage rate is shown to depend on the mode of deformation.
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