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2022 ◽  
pp. 1373-1387
Author(s):  
Irudaya Rajan S. ◽  
Sunitha S.

Aging is a natural phenomenon in which widowhood and disability are the major characteristics of concern. The main objective of the chapter is to sift the relationship between widowhood and disability by gender. It examines the factors affecting female elderly with the disability and measures both subjective and objective disabilities. This study is evidenced from the Kerala Ageing Survey (KAS), 2013, with a sample of 7668 elderly in which 58% are females. Three major physical disabilities, namely vision, hearing, and walking, and mental disabilities, such as cognitive impairment and depression, are to be analyzed through the data. Before that, disability trends and prevalence of both India and Kerala by age and sex are closely examined through census figures. It is revealed that elderly women are at risk of many factors compared to their male counterparts. They are vulnerable to multiple disabilities. The prevalence of disability is more among elderly females after the age of 70. The main physical problem of elderly is vision followed by movement and hearing impairment.


2021 ◽  
pp. 1-34
Author(s):  
Jannik Dreier ◽  
Jean-Guillaume Dumas ◽  
Pascal Lafourcade ◽  
Léo Robert

In 1968, Liu described the problem of securing documents in a shared secret project. In an example, at least six out of eleven participating scientists need to be present to open the lock securing the secret documents. Shamir proposed a mathematical solution to this physical problem in 1979, by designing an efficient k-out-of-n secret sharing scheme based on Lagrange’s interpolation. Liu and Shamir also claimed that the minimal solution using physical locks is clearly impractical and exponential in the number of participants. In this paper we relax some implicit assumptions in their claim and propose an optimal physical solution to the problem of Liu that uses physical padlocks, but the number of padlocks is not greater than the number of participants. Then, we show that no device can do better for k-out-of-n threshold padlock systems as soon as k ⩾ 2 n , which holds true in particular for Liu’s example. More generally, we derive bounds required to implement any threshold system and prove a lower bound of O ( log ( n ) ) padlocks for any threshold larger than 2. For instance we propose an optimal scheme reaching that bound for 2-out-of-n threshold systems and requiring less than 2 log 2 ( n ) padlocks. We also discuss more complex access structures, a wrapping technique, and other sublinear realizations like an algorithm to generate 3-out-of-n systems with 2.5 n padlocks. Finally we give an algorithm building k-out-of-n threshold padlock systems with only O ( log ( n ) k − 1 ) padlocks. Apart from the physical world, our results also show that it is possible to implement secret sharing over small fields.


2021 ◽  
Vol 29 ◽  
Author(s):  

The aim of the current research is to identify the extent to which secondary school physics teachers possess the skills to solve physical problems and to identify the differences in their physical problem solving skills according to the gender variables. The research identified physics teachers in secondary schools affiliated with the Directorate of Education in Al-Diwaniyah, for the academic year 2020-2021, and the sample size was (160) teachers who were randomly selected, and by reviewing some studies that dealt with physical problem solving skills, such as the study of (Islami et al., 2018). and study (Prasetyo, 2020). It was found that these studies share a number of points with the current research, but they did not provide a tool for measuring physical problem solving skills. Therefore, the researcher designed a scale of physical problem solving skills, which consisted of (32) items. After the exploratory application, the validity and stability of the study tool was confirmed by appropriate methods, and the correlation of the item’s degree with the total score was calculated, and after applying the test to the sample, the data was processed statistically, as the researcher used the equation of the t-test for one sample to verify that physics teachers possess the skills of solving Physical problems, and the results showed that teachers of physics possess the skills to solve physical problems, and the statistical method was used to verify the differences in the skills of solving physical problems according to gender variables (male and female), and the results showed that there are differences in favor of (male) and the researcher recommended in the light of Results Preparing special training programs by the Ministry of Education to develop physical problem solving skills among physics teachers, and suggested the need to focus on the diversity of solving processes based on physical problem solving skills.


2021 ◽  
Vol 2070 (1) ◽  
pp. 012042
Author(s):  
Mykhailo Seleznov

Abstract The paper proposes an algorithm for forming a small training set, which will provide a reasonable quality of a surrogate ML-model for the problem of elastoplastic deformation of a metal rod under the action of a longitudinal load pulse. This dynamic physical problem is computationally simple and convenient for testing various approaches, but at the same time it is physically quite complex, because it contains a significant range of effects. So, the methods tested on this problem can be further applied to other areas. This work demonstrates the possibility of a surrogate ML-model to provide a reasonable prediction quality for a dynamic physical problem with a small training set size.


Author(s):  
Sergey Shevchenko ◽  
Vladimir Tokarevsky

This article is the review of results that were obtained at 2007-2021 years development of “The Information as Absolute” concept and the informational physical model, which is based on the concept; including a number of fundamental physical problems are briefly considered in framework of the conception and the model. Recently in physics there are several publications, that present lists of the problems. However, those lists are essentially incomplete, for at least two reasons. Firsts of all, a number of phenomena are studied traditionally by philosophy, and so corresponding problems are usually considered to be “metaphysical”. However, they relate also to some concrete physical phenomena. For example, physics evidently studies Matter, and so the metaphysical problems “what is ontology of Matter”, “what is “Space”, “Time” and a few other physical phenomena and notions as well, are really a Meta-physical problem “what does physics study?” There are other fundamental physical problems, which are not considered as such in physics, and are absent in the “fundamental problems lists”. Those include the problems, which really exist, yet are incorporated into standard physical theories, and so are fundamental “implicitly”, which in physics are “solved by default”. Note, though, that a number of “Meta-physical”, and concrete fundamental, problems in detail are considered in the paper “The Informational Conception and Basic Physics”, arXiv:0707.4657, v5 (2021), so in this paper some selected common physical problems are considered, and, besides, the problems “What is Life” and “Cosmology”.


Quantum ◽  
2021 ◽  
Vol 5 ◽  
pp. 548
Author(s):  
Zhenyu Cai

Even with the recent rapid developments in quantum hardware, noise remains the biggest challenge for the practical applications of any near-term quantum devices. Full quantum error correction cannot be implemented in these devices due to their limited scale. Therefore instead of relying on engineered code symmetry, symmetry verification was developed which uses the inherent symmetry within the physical problem we try to solve. In this article, we develop a general framework named symmetry expansion which provides a wide spectrum of symmetry-based error mitigation schemes beyond symmetry verification, enabling us to achieve different balances between the estimation bias and the sampling cost of the scheme. We show that certain symmetry expansion schemes can achieve a smaller estimation bias than symmetry verification through cancellation between the biases due to the detectable and undetectable noise components. A practical way to search for such a small-bias scheme is introduced. By numerically simulating the Fermi-Hubbard model for energy estimation, the small-bias symmetry expansion we found can achieve an estimation bias 6 to 9 times below what is achievable by symmetry verification when the average number of circuit errors is between 1 to 2. The corresponding sampling cost for random shot noise reduction is just 2 to 6 times higher than symmetry verification. Beyond symmetries inherent to the physical problem, our formalism is also applicable to engineered symmetries. For example, the recent scheme for exponential error suppression using multiple noisy copies of the quantum device is just a special case of symmetry expansion using the permutation symmetry among the copies.


2021 ◽  
Vol 26 (3) ◽  
pp. 211-223
Author(s):  
V. F. Pushin ◽  
◽  
L. F. Chernogor ◽  

Purpose: The ionospheric channel is widely used for the communication, radio navigation, radar, direction finding, radio astronomy, and remote radio probing systems. The radio channel parameters are characterized by nonstationarity due to the dynamic processes in the ionosphere, and therefore their study is one of the topical problems of space radio physics and earth-space radio physics of geospace. This work aims at presenting the results of synthesis of temporal variations in the Doppler spectra obtained by the Doppler probing of the ionosphere at vertical and quasi-vertical incidence. Design/methotology/approach: One of the most effective methods of ionosphere research is the Doppler sounding technique. It has a high time resolution (about 10 s), a Doppler shift resolution (0.01–0.1 Hz), and the accuracy of Doppler shift measurements (~0.01 Hz) that permits monitoring the variations in the ionospheric electron density (10–4–10–3) or the study of the ionospheric plasma motion with the speed of 0.1-1 m/s and greater. The solution of the inverse radio physical problem, consisting in determination of the ionosphere parameters, often means solving the direct radio physical problem. In the Doppler sounding technique, it belongs with the construction of variations in Doppler spectra and comparing them with the Doppler spectra measurements. Findings: For the radio wave ordinary component, three echoes being produced by three rays are observed. Influence of the geomagnetic fi eld and large horizontal gradients in the electron density of δ≥10 % give rise to complex ray structures with caustic surfaces. The ionospheric disturbances traveling along the magnetic meridian form the skip zones. The longitudinal and transverse displacement of the ray reflection point attains a few tens of kilometers along the vil. Haidary to vil. Hrakove quasi-vertical radiowave propagation path, for which the great circle range is 50 km. For the vertical incidence, the signal azimuth at the receiver coincides with the traveling ionospheric disturbance azimuth. The synthesis of temporal variations in the HF Doppler spectra has been made and compared with the temporal variations in the Doppler spectra recorded with the V. N. Karazin Kharkiv National University radar. The estimate of δ=15 % obtained confirms the existence of large horizontal gradients in electron density. Conclusions: Temporal variations in Doppler spectra and in azimuth have been calculated for the vertical and quasi-vertical incidence with allowance for large horizontal gradients of the electron density caused by traveling ionospheric disturbances. Key words: ionosphere, Doppler sounding at oblique incidence, synthesis of temporal variations in HF Doppler spectra, traveling ionospheric disturbances, electron density


2021 ◽  
Author(s):  
Kelsey R Allen ◽  
Kevin Smith ◽  
Laura-Ashleigh Bird ◽  
Joshua B. Tenenbaum ◽  
Tamar Makin ◽  
...  

'Embodied cognition' suggests that our experience in our bodies -- including our motor experiences -- shape our cognitive and perceptual capabilities broadly. Much work has studied how differences in the physical body (either natural or manipulated) can impact peoples' cognitive and perceptual capacities, but often these judgments relate directly to those body differences. Here we focus instead on how natural embodied experience affects what kinds of abstract physical problem-solving strategies people use in a virtual task. We compare how groups with different embodied experience -- children and adults with congenital limb differences versus those born with two hands -- perform on this task, and find that while there is no difference in overall accuracy or time to complete the task, the groups use different meta-strategies to come to solutions. Specifically, both children and adults born with limb differences take a longer time to think before acting, and as a result take fewer overall actions to reach solutions to physical reasoning problems. Conversely, the process of development affects the particular actions children use as they age regardless of how many hands they were born with, as well as their persistence with their current strategy. Taken together, our findings suggest that differences in embodied experience drive the acquisition of different meta-strategies for balancing acting with thinking, deciding what kinds of actions to try, and deciding how persistent to be with a current action plan.


2021 ◽  
Vol 39 (2) ◽  
pp. 433-440
Author(s):  
Mohammed Aissa ◽  
Azzedine Boutelhig

Only scarce studies that were adopted have considered two properties, the structure safety and energy, where the aero-dynamic and energetic phenomena were taken into account simultaneously in the agricultural greenhouses area. In fact, in this numerical study, the response of the greenhouse has been investigated in outside climate conditions, by considering the orientation relatively to the wind direction velocity and solar trajectory. A resolution of the physical problem combined between the thermal and dynamical fluid flow equations have been based on the Ansys Fluent software. The results showed that the difference between inside and outside air temperature of greenhouse has been strongly affected by the reorientation of the tunnel greenhouse structure, or by the design of the tunnel structure that was adopted in the dome and chapel shape. Moreover, the safety properties of greenhouse structure linked to the drag stress can be developed when based on the interaction fluid-structure analysis. In this view, a temperature profile evolution versus different heights inside greenhouse was highlighted. As well as like continues of our previous study of the drag evolution over tunnel design body proved by the results found in the literature will be compared with chapel and dome designs.


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