A study on digital eye strain among patients attending at one of the tertiary care hospitals of Saurashtra region, Gujarat

Digital Eye Strain (DES) is a group of eye and vision-related problems that result from prolonged computer, tablet, e-reader and cell phone use. Majority of scientific literature available for DES has targeted only youth/young people, overlooking rest age-groups.Aim of this study was to assess the prevalence of DES and its various risk factors of digital device usage pattern and to correlate them statistically with clinical features. The study was conducted at medical college attached hospital in Amreli district, Gujarat, India during June – September 2020. Total 320 study participants were included in research. All patients attending ophthalmic OPD during study –period were screened for DES related symptoms and history of digital device usage. Information collected for socio-demographic profile, pattern of device usage and reported clinical features. Data were entered in MS Excel and analyzed through SPSS software. Majority of study participants (47.81%) belonged to 18-30 years’ age-group, 186(58.13%) were males. Major symptoms of DES reported were: Headache (77.81%) dry-eye (61.56%), Temporary Difficulty in gaze (51.25%), Red-eye (49.37%) and blurred vision (44.68%). Of total, 59.06% and 9.06% respectively used digital device for 4-6 hours and >6 hours per day. Approximate screen distance <50 cm. from eyes was preferred by 192(60%) participants. Bright contrast setting was preferred by majority (253, 79.05%). Taking break after 30 minutes of continuous usage was preferred by 84 (26.25%) participants. Role of age and gender was found statistically significant in occurrence of many of symptoms of DES. Approximate distance of digital device from eyes revealed significant association with burning, dry and red eyes, headache and temporary difficulty in gaze. Taking preferred break after 30 minutes of continuous usage of digital device, all clinical symptoms revealed significant association except double vision. Dry eyes, temporary difficulty in gaze and blurred vision revealed comparatively more risk with pattern optical aid usage.

Precise clustering analysis of Internet financial credit reporting dependent on multidimensional attribute sparse large data

Given that the traditional methods cannot perform clustering analysis on the Internet financial credit reporting directly and effectively, a kind of precise clustering analysis of internet financial credit reporting dependent on multidimensional attribute sparse large data is proposed. By measuring the overall distance between Internet financial credit reporting through the sparse large data with multidimensional attributes, the multidimensional attribute sparse large data are used to perform clustering analysis on the overall distance matrix and the component approximate distance matrix between the data, respectively. The correlation relationship between the Internet financial credit reporting under these two perspectives is taken into comprehensive consideration. Multidimensional attribute sparse large data pairs are used to reflect the comprehensive relationship matrix of the original Internet financial credit reporting to achieve clustering with relatively high quality. Numerical experiments show that compared with the traditional clustering methods, the method proposed in this paper can not only reflect the overall data features effectively, but also improve the clustering effect of the original Internet financial credit reporting data through the analysis of the correlation relationship between the important component attribute sequences.

A Hybrid Approach for Shape Retrieval Using Genetic Algorithms and Approximate Distance

This article describes how the classical algorithm of shape context (SC) is still unable to capture the part structure of some complex shapes. To overcome this insufficiency, the authors propose a novel shape-based retrieval approach that is called HybMAS-GA using a multi-agent system (MAS) and a genetic algorithm (GA). They define a new distance called approximate distance (AD) to define a SC method by AD, which called approximate distance shape context (ADSC) descriptor. Furthermore, the authors' proposed HybMAS-GA is a star architecture where all shape context agents, N, are directly linked to a coordinator agent. Each retrieval agent must perform either a SC or an ADSC method to obtain a similar shape, started from its own initial configuration of sample points. This combination increases the efficiency of the proposed HybMAS-GA algorithm and ensures its convergence to an optimal images retrieval as it is shown through experimental results.

Roads and Communication Routes in the South of Western Siberia in the 18th Century in the Coverage of Russian Historiography

The article is devoted to the analysis of degree and nature of reflection of the problem of the genesis and evolution of transport communications in the south of Western Siberia in the 18th century in Russian historical research. The source base of the research was the Siberian studies literature of the 18th - early 21st centuries, devoted to or concerning the formation of communication routes in Altai and the Irtysh region, which is chronologically divided into three periods (pre-revolutionary, Soviet and modern), the presentation of the last two arranged problem-chronologically. In pre-revolutionary works, information about the region's roads was isolated (sporadic), usually in the context of personal observations of a traveler, calculations of the approximate distance between administrative objects or mentions of existed trade routes. Studies of the Soviet period affected on major overland and water routes, their role in colonization of the territory, and their relationship to population movements. Modern historiography presents some experiences of wide coverage of the history of communication routes in the south of Western Siberia, the region's roads are traditionally considered either as departmental tracks or in the context of expedition itineraries of individual detachments.

Uitsiton: wearable for mobility of the visually impaired

This article explains the development of the Uitsiton system, capable of detecting obstacles to alert visually impaired users, increasing their mobility and confidence when moving. Uitsiton is made up of a portable electronic device (wearable) and a mobile application (App) that operates under the Android platform. The wearable is integrated into a vest-like garment. It is used to compute the approximate distance between the visually impaired user and the obstacles that they can find in their path. The wearable covers a range of 180 degrees vertically and horizontally with respect to the center of the torso, and reaches a maximum distance of 120 cm. The App works synchronously with the wearable, it receives a series of data corresponding to the measurements of the distance between the user and the obstacle, and it triggers a sound pattern and a vibration pattern according to the proximity of the obstacle.

The white dwarf planet WD J0914+1914 b: barricading potential rocky pollutants?

An ice giant planet was recently reported orbiting white dwarf WD J0914+1914 at an approximate distance of 0.07 au. The striking non-detection of rocky pollutants in this white dwarf’s photosphere contrasts with the observations of nearly every other known white dwarf planetary system. Here, I analyse the prospects for exterior extant rocky asteroids, boulders, cobbles, and pebbles to radiatively drift inward past the planet due to the relatively high luminosity ($0.1 \, \mathrm{L}_{\odot }$) of this particularly young (13 Myr) white dwarf. Pebbles and cobbles drift too slowly from Poynting–Robertson drag to bypass the planet, but boulders and asteroids are subject to the much stronger Yarkovsky effect. In this paper, I (i) place lower limits on the time-scales for these objects to reach the planet’s orbit, (ii) establish 3 m as the approximate limiting radius above which a boulder drifts too slowly to avoid colliding with the planet, and (iii) compute bounds on the fraction of boulders that succeed in traversing mean motion resonances and the planet’s Hill sphere to eventually pollute the star. Overall, I find that the planet acts as a barrier against rather than a facilitator for radiatively driven rocky pollution, suggesting that future rocky pollutants would most likely originate from distant scattering events.

A Simple Approach for Vortex Core Visualization

We propose a method to visualize vortex cores based on manipulation of the pressure field produced by isolated vortices in incompressible flow. Under ideal conditions, the function D=2|∇p|/∇2p yields an approximate distance to vortex centerlines. As opposed to local methods to identify coherent structures, isosurfaces of D produce a field of vortex tubes equidistant to the vortex core center which, ideally, are independent of vortex intensity or size. In contrast to other line-vortex identification methods, which typically rely on algorithms to detect vortex core lines and frequently need complex implementations, the proposed method can be computed from the local Eulerian velocity and pressure fields as easily as vortex identification methods such as the Q and λ2 criteria. D=2|∇p|/∇2p results in the exact distance to the core center for a Rankine vortex and is in general valid for the region of a vortex where there is pure rotation, yielding an approximation to the distance farther from the core in other simple one-dimensional vortex models. The methodology performs well in all tests we attempted, though limitations are presented and discussed. The method is demonstrated for a canonical Burgers vortex, a Bodewadt vortex, homogeneous isotropic turbulent flow, the wake of a propeller, a heaving plate, and a turning containership. The proposed method helps to better visualize vortical flow fields by displaying vortex cores, complementing methods like Q and λ2 which display vortical volumes.