scholarly journals Comparative analysis of the chosen properties of filtrating type protective masks

2014 ◽  
Vol 68 (4) ◽  
pp. 457-464 ◽  
Author(s):  
Dusan Rajic ◽  
Zeljko Kamberovic ◽  
Radovan Karkalic ◽  
Maja Vitorovic-Todorovic ◽  
Negovan Ivankovic ◽  
...  
Keyword(s):  
Optical Properties ◽  
Comparative Analysis ◽  
Standardized Testing ◽  
Experimental Testing ◽  
Field Of View ◽  
Quality Level ◽  
Dynamic Resistance ◽  
Testing Methods ◽  
Protection Factor ◽  
Previous Generation

The results of comparative experimental testing of different filtrating type masks are presented in this study. Some of the most important functional properties have been tested on available models of Italian, French, British, Canadian, Swiss, American, and three models of Serbian military protective masks (M3 of the latest generation, as well as M2, and M2FV models of the previous generation). Using of the standardized testing methods, mask models have been tested on protection factor, dynamic resistance of the exhaust valve and its static permeability, the overall inhalation resistance of protective masks, field of view and optical properties. Based on experimental results obtained, it can be concluded that the Serbian mask M3 is on approximately same quality level as tested foreign masks, and above Serbian protective masks of the previous generation marked M2F and M2FV.

scholarly journals A comparative analysis of non­reference assessment methods

Connectivity ◽  
2020 ◽  
Vol 148 (6) ◽  
Author(s):  
V. V. Grebenyuk ◽  
◽  
O. A. Dibrivnyy ◽  
O. V. Nehodenko
Keyword(s):  
Comparative Analysis ◽  
Image Quality ◽  
Image Quality Assessment ◽  
Excellent Result ◽  
Video Quality ◽  
Mean Value ◽  
Performance Comparison ◽  
Quality Level ◽  
Reference Methods

A comparative analysis of functions to assess image quality in the absence of a sample: no-reference (NR) measure or NR-type methods. The availability of NR-methods is very important for assessing the quality of streaming video such as television, game streaming, online conferences, web-chatting, etc. (because on the side of the recipient of the video there is no standard for quality comparison) and assessing the results of transformations aimed at improving video, and choosing the parameters of these transformations (brightness change, semitone and others). The human visual system (HVS) is able to visually assessing video quality, but If required to visually assess the quality of dozens or hundreds of videos or ranking them by quality level it will be needed a huge amount of time. Six types of experiments were performed to analyze the correlation of calculated quantitative estimates with visual assessments of the quality of the tested video files. Three of them are fundamentally new: comparing video after gamma correction and changing the contrast with different parameters, as well as blurring, which may be the result of defocusing the camcorder. A hybrid method (or reduced-reference (RR) measure) and a full-reference (FR) measure or FR-type method were also added for comparison. It has been experimentally shown that none of the studied non-reference methods of image quality assessment is universal, and the calculated assessment cannot be converted into a quality scale without taking into account the factors influencing the distortion of image quality. Moreover, all NR-type methods could not cope with the experiment of changing the contrast, believing that the best result is the most contrasting image but the original. Instead, the reference methods showed an excellent result (except one, which showed partial ineffectiveness). Also, it has been shown performance comparison between methods. It is shown that most of the studied methods calculate local estimates for each frame, and their arithmetic mean value is an estimate of the quality of the entire video file. If the video is dominated by large areas of uniform evaluation, methods of this type may give incorrect quality evaluations that do not coincide with the visual evaluations.

scholarly journals Электронная структура и оптические спектры соединений GdFeAl и GdFeSi

2021 ◽  
Vol 63 (6) ◽  
pp. 700
Author(s):  
Ю.В. Князев ◽  
А.В. Лукоянов ◽  
Ю.И. Кузьмин ◽  
А.Г. Кучин ◽  
С.П. Платонов
Keyword(s):  
Optical Properties ◽  
Electronic Structure ◽  
Comparative Analysis ◽  
Optical Conductivity ◽  
Electronic States ◽  
Wavelength Interval ◽  
Correlation Effects ◽  
Calculated Density ◽  
Density Of Electronic States ◽  
Conductivity Spectra

Results of investigations of electronic structure and optical properties of GdFeAl and GdFeSi compounds are presented. Spin-plarized density of states and interband optical conductivity spectra were calculated in frame of DFT+U technique with a correction for strong correlation effects in 4f shell of Gd. Optical properties were measured by ellipsometric technique in wavelength interval of 0.22 – 16 μm. Nature of quantum light absorption is discussed on the base of comparative analysis of experimental and calculated spectra. It is shown that main features of frequency dependencies of the optical conductivity are interpret qualitatively by the calculated density of electronic states.

scholarly journals Selected Problems of Experimental Testing Marine Stern Tube Bearings

2019 ◽  
Vol 26 (2) ◽  
pp. 142-154
Author(s):  
Agnieszka Barszczewska ◽  
Ewa Piątkowska ◽  
Wojciech Litwin
Keyword(s):  
Experimental Testing ◽  
Experimental Tests ◽  
Main Shaft ◽  
Testing Methods ◽  
Wide Range

Abstract This paper presents typical methods for conducting experimental tests on main shaft slide bearings. There are described their possible testing capabilities, advantages, drawbacks and limitations. Various testing methods were analyzed to find a solution able of providing a wide range of possible investigations at possibly acceptable limitations.

scholarly journals IMPROVEMENT OF THEORETICAL COMPETENCE OF BEGINNER ATHLETES IN CYCLIC SPORTS

2020 ◽  
Author(s):  
Viktoriia Bohuslavska ◽  
Іvan Hlukhov ◽  
Maryn Pityn
Keyword(s):  
Theoretical Analysis ◽  
Experimental Testing ◽  
Training System ◽  
General Level ◽  
Initial Training ◽  
Testing Methods ◽  
Interactive Tools ◽  
Literary Sources ◽  
Legislative Framework ◽  
Effectiveness Of Training

Introduction. Despite the constant modernization of the athletes’ training system, as well as the existing legislative framework aimed at innovative transformations in the field of physical education and sports, currently, there is no information on the use of interactive tools in the theoretical training of athletes in cyclic sports, and it does not meet modern requirements for training athletes. The study aimed to compare the effectiveness of training with the use of traditional and author’s interactive tools of theoretical training of beginner athletes in cyclic sports. Material and methods. In this work, the following research methods were used: theoretical analysis and generalization of literary sources, pedagogical observation, pedagogical experiment, pedagogical testing, methods of mathematical statistics. The study included 36 people involved in kayaking and canoeing at the stage of initial training. The sports experience of the subjects was 1-2 years, qualification at the level of III sports categories. Classes on the developed programs were conducted in the preparatory period of the macrocycle. Results. Training, in which only the theoretical training tools recommended by the curriculum were used, proved to be ineffective in most sections of knowledge at the stage of initial training of athletes. Training sessions with the use of interactive tools proved to be more effective than classes that used only the theoretical training tools recommended by the curriculum. Conclusions. Classes with the use of interactive theoretical training tools contributed more to the increase of the general level of theoretical training of young rowers at the stage of initial training - up to 57,4 % (p < 0.05) than classes using only theoretical training tools recommended by the curriculum. - up to 40,8 % (p < 0.05). Prospects for further research in this direction include the development and experimental testing of the author’s interactive tools for theoretical training, which will increase the level of theoretical training of athletes at different stages of training in cyclical sports.

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