bluuebunny/crossref_metadata_2025 huggingface dataset:
Tracking Intrinsic Properties of CH3NH3PbI3 Perovskite Thin Films Grown by Spin Coating Technique at Ambient Temperature
Authors: Mosiori Cliff Orori , Maera John
Published: March 2020

Methyl ammonium lead iodide has become a burgeoning class of hybrid halide perovskites of solution-processed semiconductors. Advancements in its processing and characterization underscore structural, optical, and electronic properties. They have led to the development of perovskite solar cells, photo detectors, lasers, and photo diodes with power conversion efficiencies mature to be classified as first and second-generation technologies. Characterizing forms an integral understanding the operating principles and fundamental limitations for optoelectronics applications. Studies outlined in this paper covers CH3NH3PbI3 using time-resolved pump-probe spectroscopy, X-ray diffractometry, spectrophotometry and other measurements. Thus this investigatiosn may serve as principle tool in analyzing excited state decay kinetics and optical nonlinearities in CH3NH3PbI3 thin films. It is demonstrated herein that non-resonant photoexcitation yields a large fraction of free carriers on a sub-picosecond time scale. If applied in practical optoelectronic applications then any photogenerated carriers may travel long carrier lengths before they are extracted to realize large external quantum efficiencies and efficient charge extraction. The optical constants of CH3NH3PbI3 are interpreted using ab initio calculations through models. Findings show good agreement between the optical constants derived from QSGW and those from related literature. Transition from the highest valence band (VB) to the lowest conduction band (CB) was found to be responsible for almost all the optical responses between 1.2 and 5.5 eV. It was concluded that optical constants and energy band diagrams of CH3NH3PbI3 can be used to simulate the contributions from different optical transitions to a typical transient absorption spectrum for many optoelectronic applications.
Using Markov Analysis to Study the Impact of Temperature in Bangladesh
Authors: Mahanta Janardan , Nath Soumen Kishor , Rashid Md. Haronur
Published: March 2020

In this paper has been studied the temperature trend in Bangladesh. Long-term changes of surface air temperature over Bangladesh have been studied using the available historical data collected by the Bangladesh meteorological Department (BMD). Daily temperature data is collected from BMD in Dhaka and Chittagong. Then month have been divided according to season and their descriptive statistics are computed. Maximum average temperature in pre-monsoon season and minimum average temperature in winter season have been shown in the paper. This study also reveals that temperature has increased over the time. Markov chain analysis has been applied for these data so as to find the stationary probability. After 26 and 13 days stationary probabilities in Dhaka and Chittagong stations respectively have observed.
Sources of Environmental Hazards Effects and Control
Authors: Iderawumi Abdulraheem Mukhtar
Published: March 2020

The entire world become village and whatever affects a country will ultimately affect the neighbouring ones.  Since the environment is being constantly polluted by man through its various activities such an acts constitutes hazard to man and its ecological being and a threat to public health. An environmental hazard is a substance, state or event which has the potential to threaten the surrounding natural environment and / or adversely affect people's health. This term incorporates topics like pollution and natural disasters such as storms and earthquakes. Human-made hazards while not immediately health-threatening may turn out detrimental to man's well-being eventually, because deterioration in the environment can produce secondary, unwanted negative effects on the human ecosphere. The effects of water pollution may not be immediately visible because of a sewage system that helps drain off toxic substances. If those substances turn out to be persistent (e.g. persistent organic pollutant), however, they will literally be fed back to their producers via the food chain: plankton -> edible fish -> humans. In that respect, a considerable number of environmental hazards are man-made (anthropogenic) hazards. This necessitate to this study of investigating, the sources, effects and controls of environment hazards. Data were gathered from Primary Health Care (P.H.C) department and from environment department through oral interview method. The findings from the data collected revealed that’s the people in the study area have negative attitude towards environmental hazards which make them to mismanage environmental resources such as land, water and air. Investigation also shows that, there were poor and inadequate system of refuse disposition and that the system most of the houses in the area are without adequate toilet facilities. Health education should be given to the people on the sources and effects of environmental hazards. It is therefore hoped that, if the recommendation made in this study is staffs strictly adhered to, it would go a long way in improving the environmental condition.
Impact the Temperature of Bangladesh: An Application of Markov Model
Authors: Mahanta Janardan , Hossain Syed Tanjim , Reza Imtiaz
Published: March 2020

Markov chain model has been used to analyze the temperature of Bangladesh. Different order Markov chain model has constructed and their significance has been tested. Using Cramer’s , strength the association of temperature with the order of Markov chain has been measured. Stationary probability has been calculated, and there have been employed whether the temperature is stationary or not.
Performance Evaluation of Single Slope Solar Still by Integrating with Solar Thermal Systems
Authors: Sivakumaran R. , Jdihesh P.
Published: March 2020

The world is facing the state of being scarce of fresh or drinking water and it is the major problem and global challenge. Along with air and food, water is a basic necessity for human. Solar energy is the biggest source of energy available on earth. A solar distillation is one of the methods for purifying salt water to drinking water. In this method fresh water is obtained by exposing a small layer of salt water to solar radiation and the water vaporized from the basin is condensed on the bottom side of a taper transparent cover. It can be collected in receiving troughs at the end of the still. For this research, a solar still has been designed, fabricated and tested under the climate condition of Coimbatore (11.01680 N, 76.9550 E), India from December 2016 to March 2017. The still basin area was 1m2 and the glass cover of still is inclined at 13 degree based on the city latitude. Solar still is integrated with thermal system such as solar photovoltaic system and then with solar pond in order to preheat the feed water thereby increasing the productivity considerably. Experiments were carried out on the still using different parameters and tested for performance. The results showed that the daily production of the conventional solar still was 2 Lit/m2/day and integrated with photovoltaic system and solar pond was 3.1 Lit/m2/day and 2.54 Lit/m2/day respectively.
A Parametric Study Of Window, Orientation And Shading to Minimize Energy Consuption in Mechanically Ventilated High Rise Office Buildings in Dhaka, Bangladesh
Authors: Hossain Md Shajjad
Published: March 2020

Vital statistics of a building, meaning geometric attributes, are very important design tool to manipulate energy performance of a building which is often neglected. Though a lot of recent researches focused on increasing capabilities of material and technology to build energy efficient buildings, design elements such as form, shape, window, orientation, etc. can play a very important and effective role to increase energy efficiency. The strategic design decisions about geometric attributes in the design phase costs almost nothing and can save energy bills through lifetime of the building, which is yet be specified in particular climatic region and particular building types where energy consumption matters in national scale. This paper investigates the critical proportion of façade glazing through parametric study by simulation to obtain optimum balance between luminous and thermal behavior as well as energy consumption. The context of the study is Dhaka, with tropical monsoon climate where heat and humidity is a big concern. The experiment is carried out and hence relevant to highrise office building due to its large vertical surface compared to insignificant roof area. The outcomes indicate that significant harvesting of daylight and reduction of total energy consumption by 50% comes with proper shading on large glazing on East and West facade; and 30% on South facade.
Performance Evaluation of Multiple Helical Tubes as a Receiver for Solar Parabolic Trough Collector
Authors: Lotake Swapnil N. , Wagh M. M.
Published: March 2020

Solar parabolic trough collector consists of a parabolic reflector with a central receiver at a focal point through which heat transfer fluid is passed. Parabolic trough collector is used mostly in solar thermal power plants for generating electricity. This paper describes the experimental results of two straight tubes wrapped over each other to form a helically shaped receiver. The receiver was tested with aluminium material with and without black paint over it. Also, the helical tube receiver was tested with a glass cover over it, at two different mass flow rates and, with and without manual tracking. The tested instantaneous thermal efficiency ranges from 31.26% to 45.28% and the overall thermal efficiency ranges from 14.9% to 31.41% during the experimental period. The instantaneous thermal efficiency increased by an average of 1.32 times for unpainted receiver and 1.36 times for black painted receiver with the increase in mass flow rate. By tracking the parabolic collector according to sun’s position, there is an average increase in instantaneous thermal efficiency by 1.1 times for unpainted receiver and 1.04 times for black painted receiver. The paper further reveals that the use of multiple helical tubes as a receiver for parabolic trough collector increases the overall efficiency of the collector in a substantial manner.
A Case Study Of The Environmental Impact Assessment Legislations In Sarawak, Malaysia
Authors: Ho Daniel Tang Kuok
Published: March 2020

Environmental Impact Assessment (EIA) is a planning tool used to identify, predict, evaluate and mitigate the environmental effects of development projects. In Sarawak, EIA is governed by the both the State and the Federal EIA Orders. This leads to ambivalence in determining the legislation under which a prescribed activity demanding an EIA falls. This case study aims to investigate the implications associated with the coexistence of both EIA Orders in the state of Sarawak from the viewpoints of practicing environmental consultants. The case study reviews the EIA legislations governing EIA practices in the State and includes a qualitative survey involving practicing EIA consultants to gather feedback on the implications associated with the EIA practices and recommendations to resolve the problems identified. The study shows that even though a prescribed activity is defined by the EIA legislations, different stages of the prescribed activity eventually become prescribed activities on their own, which demand fulfillment of different EIA legislation. Unclear demarcation of EIA jurisdiction and different requirements on the scope of an EIA particularly for earthworks also contribute to doubts among environmental consultants interviewed. Consultation, involvement and effective communication with environmental protection as priority are crucial to minimize any uncertainty resulted from co-implementation of both the EIA legislations. Future study can look into comparing perceptions on the effectiveness of the State and the Federal EIA legislations. The case study delves into a crucial issue related to EIA practices in Sarawak, Malaysia which has persisted without being formally addressed in any previous studies.
The Value of Solar Photovoltaics in an Isolated Competitive Electricity Market: a Case Study of Singapore
Authors: Finenko Anton , Jindal Gautam , Owen Anthony D , Tao Jacqueline , Xiying Liu
Published: March 2020

With a view of achieving its obligations under the global climate change regime, and low technical potential for other renewable energy technologies, solar photovoltaics (PV) is the main focus for Singapore to generate low carbon electricity. However, a high penetration of PV in Singapore’s electricity market would result in a number of costs and benefits that need to be quantified in order to ensure prudent government policies for “supporting” the widespread adoption of PV in Singapore. The quantification of these costs and benefits would allow policymakers to realize the true “value” of solar PV for Singapore and would address the limitations of relying on the levelised cost of electricity metric. This paper provides an assessment of the societal value that PV would bring to Singapore, essentially an isolated power system with a liberalized electricity market. For the purpose of this study, the determination of the value of solar involves quantifying the savings due to the merit order effect, costs due to additional frequency control services, and net avoidance of CO2 emissions.
Validación de un instrumento que estima la incidencia del aprendizaje cooperativo en el estatus sociométrico de los alumnos
Authors: Ruiz Palomo Esther , Luis Rico Isabel , De la Torre Cruz Tamara , Escolar Llamazares M. Camino , Huelmo García Jonathan , Palmero Cámara Carmen , Jiménez Eguizabal Alfredo
Published: March 2020

La dinámica social establecida en la actualidad demanda de los docentes la constante actualización a través de formación. Uno de los ámbitos formativos se centra en el desarrollo e implementación dentro del aula de metodologías activas que permitan al alumno construir su propio aprendizaje. El Aprendizaje Cooperativo (AC) incide de forma directa en la construcción propia del aprendizaje desde la dimensión social, ya que es en este ámbito donde tienen cabida los procesos de aprendizaje. Nuestra investigación se centra en la influencia del AC en el estatus sociométrico del alumnado de educación primaria y secundaria. Para ello se ha desarrollado una herramienta que permite delimitar el impacto de esta metodología activa a través de la variación producida en el estatus sociométrico del alumno dentro del grupo clase. Se presenta aquí el proceso de validación de la herramienta desarrollada.
Educación para la vida y literatura infantil en la red: el caso de Davide Cali
Authors: Selfa Sastre Moises , Balca Angela
Published: March 2020

En este artículo presentamos una lectura de tres álbumes ilustrados del escritor de Literatura Infantil Davide Cali que poseen mensajes relacionados con la educación para la vida. Además señalamos la presencia de estos álbumes en la red y las interacciones digitales que los lectores pueden tener con el mensaje literario que Cali propone. Así se destacan diferentes espacios digitales, como blogs, vídeos y podcasts, que facilitan el acceso al texto literario desde diferentes ópticas y perspectivas. La lectura de estos textos, que poseen mensajes subyacentes en cada una de sus páginas, contribuye a la educación para la vida del joven lector, ya que en ellos se presentan conceptos relacionados con esta Educación: el sentido de la vida, el porqué del cumplimiento de las obligaciones cotidianas y las consecuencias del incorrecto ejercicio del poder. A partir de mensajes sencillos y de las ilustraciones que acompañan al contenido textual, Cali y los ilustradores de estos tres álbumes pretenden que el lector tome partido por los ideales allí presentados y se posicione críticamente ante ellos, contribuyendo, de este modo, a su educación para la vida.
New trends in collocability based on the English collocations in fiction
Authors: Chernousova Anna O.
Published: March 2020

The language of fiction is probably not the most dynamically but still changing. These new trends in collacability are of a great interest to us. The definition of collocation is present in the text; the authors also distinguish the concepts of collocation and lexical function. This article will discuss the trends considered in synchrony and diachrony, which were highlighted on the material of John Grisham “Gray Mountain”, which is relatively new English-language material (2014), and a bit dated J. D. Salinger “Nine Stories” (1953 ) to track trends and their development in the language. 150 examples were reviewed and analyzed. 5 trends were highlighted on a given case. The authors use dictionaries, linguistic search on the Internet, the COCA (Grisham and Salinger are both from the USA). The authors conclude that the trends that have been considered are the most frequent for the language of fiction and deserve the attention of the researchers due to their productivity. The reasons why stable word combinations change: the emergence of new realities and the need for a new nomination and (which is more typical for the prose) the search for the new forms of self-expression of the writers.
Corporate reputation analysis in social media (e. g. Wildberries online store)
Authors: Kazanina Anastasia I. , Milyukova Anna G.
Published: March 2020

This article is devoted to analyzing the reputation of Wildberries and its leader in social networks using quantitative and qualitative indicators. The specificity of the concept of "reputation capital" has been defined. The relevance of reputation capital research for the online store Wildberries was determined. The analysis of reputation risks for the company and its manager is given, possible negative events in the sphere of relations with suppliers, employees, customers, legal risks, consequences of digitalization, changes in market conditions and customers' demands are defined. The ratio of potential and realized reputational risks for the company is analyzed. It was revealed that the majority of realized risks relate to the quality of goods, professionalism of the front-office personnel and working conditions. The company's CEO's reputation positioning is assessed and recommendations are given based on the current state of affairs. The analysis of social media showed that the company has a positive reputation, but there are shortcomings that need to be addressed and addressed by management. In general, the company carries out a whole range of procedures to maintain its reputation and a sound financial position, focusing on stakeholders. It was found that the non-publicity of the manager does not have a negative impact on the reputation of the company. To form a positive reputation of the company, it is recommended to think over the photocontent, texts and tone of communication depending on the purpose of the site used, to add personification of posts, to conduct regular monitoring of all components of the company's reputation in social media to make decisions on timely correction of reputation strategy.
Conflicts in the functioning process urban communities: current state of research
Authors: Kolba Alexey I.
Published: March 2020

The article discusses the current state of research on the problems of urban communities in conflict. The research base was the corpus of domestic and foreign scientific publications, formed on the basis of a search in scientometric databases. Based on the review and analysis of scientific literature, the author identifies the main problems that are in the focus of attention of specialists: the essence of urban communities themselves, the parameters of their participation in urban politics, as well as their actual participation in conflict processes. In accordance with this, research areas and main issues that are at the center of scientific discussions are highlighted. These include the identification of the essential features of urban communities at the present stage of their development, taking into account network technologies of interaction; the formation of civil and political subjectivity of urban communities; ways to include urban communities in the system of political management of urban conflicts. The latter direction involves various formats of participation: from protest actions to the creation of collaborative planning institutions. In foreign studies at this stage, relatively more attention is paid to this issue than in Russian. The further necessity of studying the functioning of urban communities in conflict situations is substantiated.
Features of collective action in modern Russia: dynamics, digitalization and results
Authors: Sokolov Alexander V.
Published: March 2020

The article deal with the analysis of the phenomenon of collective action. A review of modern ideas about the features of collective action, mass action in politics is made. The great importance of collective identity in the process of organizing and implementing of collective actions is indicated. The network nature of modern collective actions and the significant influence of information and communication technologies in the process of their organization are noted. To illustrate the features of collective action in Russia, the article presents the results of a longitudinal study of collective action conducted since 2014 by interviewing experts from various regions of the Russian Federation (annual sample of at least 14 Russian regions and at least 155 experts). The study allows us to identify the dynamics of the activity of collective actions, the features of their organization, the trends of cooperation, the intensity of protest actions. The conclusion is made about the slowdown in the growth of civic activism and collective action. Relative growth is observed only in their manifestation on the Internet. There is a gradual decrease in the politicization of collective action and youth involvement in mass action. At the same time, the role of Internet tools in organizing politicized collective actions is increasing. The article analyzes the actors of collective action. It is concluded that the development of the Internet is a factor contributing to the formation of wider coalitions in the process of organizing and carrying out of collective actions and the increasing activity of unregistered public associations. It is indicated that there is a tendency for the development of network characteristics of collective actions in modern Russia.
Theoretical and methodological grounds for critical approach to revolution
Authors: Kudrina Sofia A.
Published: March 2020

The article is devoted to the sociological approach to the phenomenon of revolution as a “pure type” free from political and historical content. It deals with socio-ontological, methodological, socio-psychological and ethical-axiological grounds for the critical approach to the phenomenon of revolution in classical and contemporary theories. Socio-ontological arguments are proposed by sociologists who regard revolutions as disaster because social systems (as “living organisms” or any complex systems, regardless of their origin) are certain to be in balance. According to the socio-psychological critical arguments, revolutions activate irrational aggressive crowds capable of destruction only. Besides, this approach is based on the study of false interpretations and the phenomenon of the “revolution of rising expectations”. Methodological criticism aims at social revolution as an inevitable integral element of Utopian engineering. The meaning of the confrontation is as follows: piecemeal technology versus holistic large-scale experiment. According to the ethical and axiological arguments, the revolution as a violent collective action, in the name of the desired equality and justice, leads to victims inevitably.
Solidarity of generations in everyday life through the eyes of youth
Authors: Lebedeva Ludmila G.
Published: March 2020

Solidarity refers not only to the socio-political sphere, but also to the sphere of intra-family relations. Solidarity and support of generations in everyday life is one of the natural traditions of inter-generational and intra-generational relationships. Solidarity is a structure of behavior inherited by individuals, fixed in the natural-historical process of succession of generations. The purpose of the article is to analyze the problems and trends in traditional relations of intra-family solidarity and mutual assistance of generations in everyday life. Sociological materials show that the modern young generation is, for the most part, completely or mostly independent in financial and economic terms. There is a noticeable trend that today's youth are noticeably less helpful in everyday life to older generations than older generations are helping young people. On the one hand, young people are largely separated from the parental family, become independent, less and less help parents in everyday life. On the other hand, a large part of parents finds themselves in a more difficult financial and economic situation and do not have real opportunities to help their children. It is necessary to recognize the paramount importance of the care of society and the state, especially in relation to two social groups - students and older people experiencing financial difficulties and in need of daily assistance. The manifestation of care on the part of society and the state, systematic targeted support for the most financially vulnerable groups of the population in its own way will support the modern meanings of traditional relations of solidarity and mutual assistance of generations in everyday life.
Influence of the level of socio-economic development of regions on demographic and migration processes
Authors: Chistyakov Alexander E. , Shustov Alexander V.
Published: March 2020

The article deals with the problem of the influence of the level of socio-economic development of Russian regions on demographic and migration processes. The relationship between economic indicators, the total population growth in the regions and its components-natural and migration growth during 2000-2017 are analyzed. The authors reveals the relationship between the dynamics of the gross regional product (GRP) and the population of the regions, as well as the factors that determine these processes. For the purposes of the study, a sample of “typical” regions was formed. In the process of its formation, national autonomies and remote territories with a more severe climate were excluded from the total number of subjects of the Russian Federation, where the development of demographic and migration processes may be determined by "atypical" factors for other regions of the Russian Federation (national-cultural, climatic, etc.). The article analyzes the causes of internal migration and features of socio-demographic development of subjects of the Russian Federation. The role of the Moscow region as an object of migration attraction is investigated, and the factors that deter and stimulate internal migration are considered. The official data of the Federal state statistics service for 2000-2017 were used as an information base for the study.
Culture generating texts: functions, genres, authors
Authors: Karasik Vladimir I.
Published: March 2020

The paper deals with culture generating texts treated as speech products corresponding to dominant features of civilization in cultural history. Three types of such texts - sacral regulations, mass circulation products and virtual net messages - have radically changed the idea of authorship and corresponding attitudes of public to texts. The first text type brought to life selected priests who were regarded as keepers of sacral knowledge to be transmitted to coming generations, the second text type initiated numerous artisans who produced various one-time texts suitable for everyday purposes, the third text type generated illusionists who launch secondary texts through the world electronic network for the sake of carnival play with life. The characteristics of three types of text as indicators of culture have been described on the material of aphorisms. Autosemantic sentences of the first type are usually expressed as manifestations of general truth or common norms of behavior, the second type phrases function as trivial observations or specific recommendations in particular situations, whereas the third type texts have a paradoxical nature or are used as banter expressions uttered to fill the gaps in conversation. Sentences of the first type make the core golden reserve of human wisdom, and they are often used in situations of social inequality when people demonstrate their experience and right to give lessons to others. Sentences of the second type are very important for everyday routine life, and they appear in corresponding habitual situations. Sentences of the third type are applied mainly in interactions which require a critical reaction to any type of edification, either moral or utilitarian, their aim is to establish equality as such by means of ridicule of any kind of self-admiration.
Video interview in new media
Authors: Antonova Lubov G. , Makhalova Alesya I.
Published: March 2020

The article is devoted to the analysis of video interviews in new media in the context of the complex, integrated concept of «hypergenre». The material of video interviews published in YouTube, attempts to characterize genres, a complex combination of which is modern video interviews in new media. Special parameters of the hypergenre should be characterized on the Internet platform, which provides additional tools in genre design, including hyperlinks, video podcasts, special technologies for illustrating and confirming factuality, specific video metaphors and video quotes. The authors believe that, unlike print or television media, this hypergenre on the Internet platform acts simultaneously as an informational, analytical, and as an artistic and journalistic, which provides an opportunity to «consider» the features of related genres included in the integrative genre complex: conversations, chronicle notes, surveys, commentary, investigative journalism and some other media genres. Another feature of modern video interviews, explaining the special role of non-verbal signs, implicitly transmitting semantic signals in the context of video interviews, which include gestures, facial expressions, pro-semitic speaker, his personal image signs and tone of speech. As a result of the study of the new model of video interviews, the authors of the article offer a generalized media toolkit of modern hypergenre education and explain the demand and popularity of such a model in the mass media.
Deep learning application for box-office evaluation of images
Authors:   Independent researcher, Efremtsev V.G. , Efremtsev N.G. ,   Independent researcher, Teterin E.P. ,   Kovrov State Technological Academy named after V.A.Degtyarev, Teterin P.E. ,   National Research Nuclear University "MEPhI", Gantsovsky V.V. ,   Independent researcher
Published: March 2020

The possibility of application a convolutional neural network to assess the box-office effect of digital images is reviewed. We studied various conditions for sample preparation, optimizer algorithms, the number of pixels in the samples, the size of the training sample, color schemes, compression quality, and other photometric parameters in view of effect on training the neural network. Due to the proposed preliminary data preparation, the optimum of the architecture and hyperparameters of the neural network we achieved a classification accuracy of at least 98%.
Limits of applicability of the direct ray approximation in modeling optical properties of liquid-crystal diffraction gratings
Authors:   Saratov State University, Yakovlev D.D. , Yakovlev D.A. ,   Saratov State University
Published: March 2020

Using computer modeling, we estimate limits of applicability of the direct ray approximation in modeling the optical properties of liquid-crystal diffraction gratings with continuous spatial modulation of the local optic axis orientation in a liquid crystal layer. The data presented concerning the influence of the spatial frequency and character of modulation of the local optic axis, as well as the magnitude of birefringence of the medium, on the accuracy of the results obtained in this approximation are also useful in considering birefringent layers with an aperiodic variation of the local optic axis.
Person tracking algorithm based on convolutional neural network for indoor video surveillance
Authors:   Polotsk State University, Bohush R. , Zakharava I. ,   Polotsk State University
Published: March 2020

In this paper, a person tracking algorithm for indoor video surveillance is presented. The algorithm contains the following steps: person detection, person features formation, features similarity calculation for the detected objects, postprocessing, person indexing, and person visibility determination in the current frame. Convolutional Neural Network (CNN) YOLO v3 is used for person detection. Person features are formed based on H channel in HSV color space histograms and a modified CNN ResNet. The proposed architecture includes 29 convolutional and one fully connected layer. As the output, it forms a 128-feature vector for every input image. CNN model was trained to perform feature extraction. Experiments were conducted using MOT methodology on stable camera videos in indoor environment. Main characteristics of the presented algorithm are calculated and discussed, confirming its effectiveness in comparison with the current approaches for person tracking in an indoor environment. Our algorithm performs real time processing for object detection and tracking using CUDA technology and a graphics card NVIDIA GTX 1060.
Highly reliable two-factor biometric authentication based on handwritten and voice passwords using flexible neural networks
Authors:   Omsk State Technical University, Sulavko A.E.
Published: March 2020

The paper addresses a problem of highly reliable biometric authentication based on converters of secret biometric images into a long key or password, as well as their testing on relatively small samples (thousands of images). Static images are open, therefore with remote authentication they are of a limited trust. A process of calculating the biometric parameters of voice and handwritten passwords is described, a method for automatically generating a flexible hybrid network consisting of various types of neurons is proposed, and an absolutely stable algorithm for network learning using small samples of “Custom” (7-15 examples) is developed. A method of a trained hybrid "biometrics-code" converter based on knowledge extraction is proposed. Low values of FAR (false acceptance rate) are achieved.
3D-generalization of impulse noise removal method for video data processing
Authors:   North-Caucasus Federal University, Chervyakov N.I. , Lyakhov P.A. ,   North-Caucasus Federal University, Orazaev A.R. ,   North-Caucasus Federal University
Published: March 2020

The paper proposes a generalized method of adaptive median impulse noise filtering for video data processing. The method is based on the combined use of iterative processing and transformation of the result of median filtering based on the Lorentz distribution. Four different combinations of algorithmic blocks of the method are proposed. The experimental part of the paper presents the results of comparing the quality of the proposed method with known analogues. Video distorted by impulse noise with pixel distortion probabilities from 1% to 99% inclusive was used for the simulation. Numerical assessment of the quality of cleaning video data from noise based on the mean square error (MSE) and structural similarity (SSIM) showed that the proposed method shows the best result of processing in all the considered cases, compared with the known approaches. The results obtained in the paper can be used in practical applications of digital video processing, for example, in systems of video surveillance, identification systems and control of industrial processes.
Mathematics and practice of color space invariants by the example of determining the gray balance for a digital printing system
Authors:   Ural Federal University, Tarasov D.A. , Milder O.B. ,   Ural Federal University
Published: March 2020

In modern printing, a large number of tasks are associated with the mutual transformation of color spaces. In particular, the most common pair of hardware-dependent color spaces is RGB and CMYK, the mutual transformation of colors in which is ambiguous, which creates significant problems in color reproduction. To solve this problem, we propose using color space invariants — gradation trajectories and gradation surfaces, which are analogs of gradation curves for initial colorants and their binary overlays, constructed in the absolute color space of the CIE Lab. Invariants are introduced on the basis of the mathematical apparatus of the differential geometry of spatial curves and surfaces. Practical application of color space invariants involves certain difficulties associated with their complex analytical description; moreover, for most practical problems, the high accuracy of the model is redundant. For the practical application of invariants, we propose a simpler approach using natural color sampling in digital printing systems. As an example, the procedure for determining the gray balance for an electrophotographic printing press is given.
Vortex energy flow in the tight focus of a non-vortex field with circular polarization
Authors:   IPSI RAS – Branch of the FSRC ", Kotlyar V.V. ,   Crystallography and Photonics",   RAS,   Samara National Research University, Stafeev S.S. ,   IPSI RAS – Branch of the FSRC "Crystallography and Photonics" RAS,   Samara National Research University, Nalimov A.G. ,   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS,   Samara National Research University
Published: March 2020

Using Richards-Wolf formulas, we show that an axisymmetric circularly polarized vortex-free field can be focused into a sharp subwavelength focal spot, around which there is a region where the light energy flow propagates along a spiral. This effect can be explained by the conversion of the spin angular momentum of the circularly polarized field into the orbital angular momentum near the focus, although the on-axis orbital angular momentum remains zero. It is also shown that a linearly polarized optical vortex with topological charge 2 forms near the focal plane an on-axis reverse energy flow (defined by the negative longitudinal component of the Poynting vector) whose amplitude is comparable with the direct energy flow.
An efficient algorithm for non-rigid object registration
Authors:   Chelyabinsk State University, Makovetskii A. , Voronin S. ,   Chelyabinsk State University, Kober V. ,   Chelyabinsk State University, Voronin A. ,   Chelyabinsk State University
Published: March 2020

An efficient algorithm for registration of two non-rigid objects based on geometrical transformation of the template object to target object is proposed. The transformation is considered as warping of the template onto the target. To choose the most suitable transformation from all possible warps, a registration algorithm should satisfy deformation constraints referred to as regularization of non-rigid objects. In this work, we use variational functionals for affine transformations. With the help of computer simulation, the proposed method for searching the optimal geometrical transformation is compared with that of common algorithms.
On a method for calculating generalized normal solutions of underdetermined linear systems
Authors:   Samara State Technical University, Zhdanov A.I. , Sidorov Y.V. ,   Samara State Technical University
Published: March 2020

The article presents a novel algorithm for calculating generalized normal solutions of underdetermined systems of linear algebraic equations based on special extended systems. The advantage of this method is the ability to solve very poorly conditioned (possibly sparse) underdetermined linear systems of large dimension using modern versions of the iterative refinement method based on the generalized minimum residual method (GMRES - IT). Results of applying the considered algorithm to solve the problem of balancing chemical equations (mass balance) are presented.
Threshold image target segmentation technology based on intelligent algorithms
Authors:   Hengshui University, Cai Y.X. , Xu Y.Y. ,   Hengshui University, Zhang T.R. ,   Hengshui University, Li D.D. ,   Hengshui University
Published: March 2020

This paper briefly introduces the optimal threshold calculation model and particle swarm optimization (PSO) algorithm for image segmentation and improves the PSO algorithm. Then the standard PSO algorithm and improved PSO algorithm were used in MATLAB software to make simulation analysis on image segmentation. The results show that the improved PSO algorithm converges faster and has higher fitness value; after the calculation of the two algorithms, it is found that the improved PSO algorithm is better in the subjective perspective, and the image obtained by the improved PSO segmentation has higher regional consistency and takes shorter time in the perspective of quantitative objective data. In conclusion, the improved PSO algorithm is effective in image segmentation.
Orbital angular momentum and topological charge of a Gaussian beam with multiple optical vortices
Authors:   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS, Kovalev A.A. ,   Samara National Research University, Kotlyar V.V. ,   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS,   Samara National Research University, Kalinkina D.S. ,   Samara National Research University
Published: March 2020

Here we study theoretically and numerically a Gaussian beam with multiple optical vortices with unitary topological charge (TC) of the same sign, located uniformly on a circle. Simple expressions are obtained for the Gaussian beam power, its orbital angular momentum (OAM), and TC. We show that the OAM normalized to the beam power cannot exceed the number of vortices in the beam. This OAM decreases with increasing distance from the optical axis to the centers of the vortices. The topological charge, on the contrary, is independent of this distance and equals the number of vortices. The numerical simulation corroborates that after passing through a random phase screen (diffuser) and propagating in free space, the beams of interest can be identified by the number of local intensity minima (shadow spots) and by the OAM.
Focusing a second-order cylindrical vector beam with a gradient index Mikaelian lens
Authors:   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS, Stafeev S.S. ,   Samara National Research University, Kozlova E.S. ,   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS,   Samara National Research University, Nalimov A.G. ,   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS,   Samara National Research University
Published: March 2020

In this paper, we numerically simulate the focusing of a second-order cylindrical vector beam with a gradient index Mikaelian lens. It is shown that the lens forms a region of the reverse energy flow near its output surface. If the lens has an on-axis micropit, the region of the direct energy flow can be confined within the lens material, whereas that of the reverse energy flow is put out in free space.
Modeling of image formation with a space-borne Offner hyperspectrometer
Authors:   Joint Stock Company ", Rastorguev A.A. ,   Rocket and Space Center",   Progress", Kharitonov S.I. ,   IPSI RAS – Branch of the FSRC "Crystallography and Photonics" RAS,   Samara National Research University, Kazanskiy N.L. ,   IPSI RAS – Branch of the FSRC "Crystallography and Photonics" RAS,   Samara National Research University
Published: March 2020

In this paper, we developed a mathematical model of image formation that allows a predictive hyperspectral image to be generated. The model takes into account the formation of an optical image using a matrix photodetector. The paper presents a numerical modeling of hyperspectral image formation and gives estimates of spatial and spectral resolution, as well as analyzing the adequacy of the results.
Experiment with a diffractive lens with a fixed focus position at several given wavelengths
Authors:   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS, Skidanov R.V. ,   Samara National Research University, Doskolovich L.L. ,   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS,   Samara National Research University, Ganchevskaya S.V. ,   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS,   Samara National Research University, Blank V.A. ,   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS,   Samara National Research University, Podlipnov V.V. ,   IPSI RAS - Branch of the FSRC “Crystallography and Photonics” RAS,   Samara National Research University, Kazanskiy N.L. ,   IPSI RAS - Branch of the FSRC “Crystallography and Photonics” RAS,   Samara National Research University
Published: March 2020

The paper presents results of the experimental investigation of “spectral” diffractive lenses the same focus position for several given wavelengths. Two spectral diffractive lenses designed to focus radiation of three and five specified wavelengths in the visible spectrum were investigated. Using a method of direct laser writing in photoresist with iterative correction of writing parameters, we fabricated a diffractive microrelief of the spectral lenses with the height deviation from the designed relief of less than 30 nm. Using a pinhole located at the focus of the fabricated lenses, we estimated the operation wavelengths. The point spread functions of the spectral lenses at the designed wavelengths were measured with the use of a tunable laser. The imaging properties of the spectral lenses were illustrated by the images of a reference color table.
Automatic highlighting of the region of interest in computed tomography images of the lungs
Authors:   Samara National Research University, Pashina T.A. , Gaidel A.V. ,   Samara National Research University,   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS, Zelter P.M. ,   Samara State Medical University, Kapishnikov A.V. ,   Samara State Medical University, Nikonorov A.V. ,   Samara National Research University,   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS
Published: March 2020

This article discusses the creation of masks for highlighting the lungs in computed tomography images using three methods – the Otsu method, a simple convolutional neural network consisting of 10 identical layers, and the convolutional neural network U-Net. We perform a study and comparison of methods used for automatically highlighting the region of interest (ROI) in computed tomography images of the lungs, which were provided as a courtesy from the Clinics of Samara State Medical University. The solution to this problem is relevant, because medical workers have to manually select the ROI as the first step of the automated processing of lung CT images. An algorithm for post-processing images based on the search for contours, which allows one to improve the quality of segmentation, is proposed. It is concluded that the U-Net highlights the ROI relating to the lung better than the other two methods. At the same time, the simple convolutional neural network highlights the ROI with an accuracy of 97.5%, which is better than the accuracy of 96.7% of the Otsu method and 96.4% of the U-Net.