bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation of bacteria from old corrugated container slime and characterization of their biofilm-forming properties
Authors: Chen Hua , Yang Rendang , Wang Jianhua , Zhao Huifang , Wang Bin , Wo Qizhong , Zheng Bingbing
Published: March 2023

With the continuously increasing demand for paper and cardboard products, there is growing concern about the bacteria of the papermaking process. Bacterial growth not only affects normal manufacturing, but it also results in paper products with a total number of bacteria that exceeds the acceptable range, and thus poses a risk to the health of consumers. In this study, 99 pure bacterial strains were isolated from old corrugated containers (OCC) slime. The morphological, physiological, and biochemical properties of the bacterial strains were examined. Furthermore, the isolated strains were tested for their ability to form biofilms. The strains that could form biofilms were identified using 16S rDNA sequencing. The results revealed that some bacteria could form both a biofilm that adhered to the smooth tube wall, as well as abundant flocs at the bottom of the test tube. Conversely, the other bacteria could not form a noticeable biofilm. The bacteria with the most powerful biofilm-forming ability were identified as Proteus penneri, Klebsiella variicola, Klebsiella sp., and Proteus mirabilis.
Yields analysis and structural characterizations of lignin extracted from Eucalyptus globulus with catalyzed ethanol systems
Authors: Zhang Hao , Xin Changzheng , Hong Liang , Zhu Ming , Wang Na
Published: March 2023

A mild and successive method was proposed and evaluated for fractionating lignin samples from Eucalyptus globulus. The extraction efficiency and structural features of the extracted lignin samples were comprehensively investigated by a yields analysis, 1H-nuclear magnetic resonance (NMR), 13C-NMR, and two-dimensional heteronuclear single quantum coherence (2D-HSQC) NMR. The catalyzed ethanol systems consisting of ethanol, 4-methyl-2-pentanone, dimethyl sulfoxide (DMSO), formic acid, and distilled water were effective for extracting lignin from Eucalyptus globulus, and the yield of lignin was 75.2% when the extraction process was held at 145 °C for 180 min. Compared with that of the milled wood lignin (MWL), the NMR spectra of the extracted lignin fractions supported the destruction of β-O-4 units for the disappearance of Hα signals. Moreover, the striking characteristics of the extracted lignin were the destruction of ether bonds of S3,5 and the condensation of syringyl (S) and guaiacyl (G) units. In short, lignin fractions with relatively complete structures were effectively extracted with the catalyzed ethanol systems.
Fiber surface chemistry in relation to the efficiency of chlorine dioxide bleaching
Authors: Zhang Kun , Lin Xuejiao , Xing Jinghao , Zhang Haichuang , Wang Shuangfei , Nie Shuangxi
Published: March 2023

Relationships between fiber surface chemical components and the efficiency of chlorine dioxide bleaching were studied using chemical analysis in combination with attenuated total reflectance-Fourier transform infrared spectrscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). The amount of surface lignin decreased quickly at the beginning of the bleaching, and the brightness increased during the bleaching. Surface oxidation took place immediately, and the amount of lignin on the fiber surface decreased during the bleaching, especially in the first 5 min. The ratio of aromatic carbons to aliphatic carbons also decreased, which indicated that the lignin was degraded and new aliphatic carbons formed that might noticeably deposit on the surface of the fiber. The aliphatic carbons reacted with the in-situ formed hypochlorous acids, and thus affected the bleaching efficiency. Further bleaching led to the deposition of more acidic functional groups on the fiber surface with increased acidity-basicity ratios, which also affected the whole efficiency of bleaching.
Influence of a biological soaking in the presence of microbes on the tensile strength of açaí fibers
Authors: Mesquita Antonio de Lima , Arroyo Felipe Nascimento , Christoforo André Luis , Lahr Francisco Antônio Rocco , Barrero Nubia Garzon , Santana Elza Brandão , Faria Lênio José Guerreiro de
Published: March 2023

In order to contribute to the dissemination of lignocellulosic residues in the composite materials manufacturing, this study aimed to investigate the influence of a soaking in the presence of natural bacteria and fungi on the resistance to axial traction of açaí fibers (Euterpe oleracea Mart.). The stipulated factors and levels were the source of water, i.e., Rio Guamá, Pará Sanitation Company COSANPA and Cassava, as a catalyst and the mass concentration of water on the açaí cores, i.e., 2%, 4%, 6%. In this way, 9 different experimental conditions were performed, together with the reference condition, i.e., açaí fibers without the soaking. In all, 200 specimens were cast, with 10 of each composition. The analysis of variance results revealed that the individual factors were not significant in obtaining the axial tensile strength, providing equivalent results regardless of the concentration and type of water. However, the interaction between the factors was considered significant, showing that the best treatment for the fibers came from the use of 2% cassava scraps. The axial tensile strength was 47% greater than the axial tensile strength obtained from the reference sample. Furthermore, 59% surpassed the reference sample, showing the efficiency of the soaking in the presence of natural bacteria and fungi treatment.
Thermal and mechanical properties of bleached pulp-filled poly(lactic acid) composites fabricated with an internal mixing process
Authors: She Yanan , Xu Xinwu
Published: March 2023

Bioderived poly(lactic acid) (PLA) is a promising alternative for fossil-based polymers, but its poor hydrophilicity, high brittleness, and low heat-resistance are problems for its utilization. In this work, bleached softwood kraft pulp (BSKP) fiber was adopted to modify PLA with MAPP as the coupling agent, with BSKP accounting for 10 wt% to 50 wt%. Internal mixing (IM) was applied to mix the PLA/fiber blend instead of screw grinding. The thermal and mechanical properties of the composites were assessed. The IM process was proven qualified for its effective dispersion of BSKP fibers in the PLA matrix. At a fiber loading of 50 wt%, IM-processed composites acquired satisfactory tensile strength (50.49 MPa, slightly higher than PLA) and Young’s modulus (2.56 GPa, 45.8% higher than PLA). The pulp fillers matched PLA matrix well for the characteristic temperatures in thermal decomposition. The BSKP/PLA composites were thermally strengthened by pulp fibers characterized by higher content of residues. The fibers improved the interfacial crystallinity of PLA in the composites (i.e., from 5.22% to 11.86%). The increased crystallinity resulted in enhanced stiffness or weaker damping performance of the composites. In conclusion, natural plant fibers are a feasible option to modify PLA for extended applications.
Freedom of religion in Ukraine: challenges during the russian-ukrainian war
Authors: KOLODNYI Anatolii , FYLYPOVYCH Liudmyla
Published: March 2023

The article is updated by several circumstances, which the authors reflect on. In their opinion, there are 1) obvious and external threats — violations of freedom of conscience in the temporarily occupied Ukrainian territories, including Crimea, which arose as a result of the Russian-Ukrainian war, and 2) internally hidden and potential dangers for freedom of religions of Ukrainian citizens. The well-known examples of discrimination of believers of certain faiths in the so-called DPR-LPR and Crimea given by the authors are constantly updated. Relevant monitoring and analytical reports are prepared by both Ukrainian and international experts. They submitted these reports to international human rights organizations, including the rights for Freedom of Religion and Belief. Despite such convincing documented materials, separate accusations have recently appeared against Ukraine, which allegedly violates freedom of religion in the territory under its control. Some are trying to prove that Ukraine, taking advantage of the war situation and referring to the spiritual dangers for Ukraine from those religious organizations whose centers are in the aggressor country, threatens some churches, thereby violating the Constitution and the Law on Freedom of Conscience, which guarantee for all citizens, regardless of from their religious affiliation, freedom of religion. The authors refute these narratives lashed out by Russia and the Russian Orthodox Church. Such negative conclusions, which express concern about the situation in Ukraine regarding freedom of conscience and religion, influence on the world public, experts on issues of freedom of conscience, religious organizations, spoil the image of Ukraine as a country with high level of freedom of conscience even among European countries. Religious freedom, as the authors conclude, needs protection today, but they call for separating real threats from imaginary ones and clearly defining who persecutes, whom he/she persecutes and where persecutes. Ukraine is consistent in its intentions to protect the rights of people and communities, to protect the freedoms of believers and their organizations.
First record of a natural hybrid of the genus Gongora (Stanhopeinae) and comments on the parent species
Authors: Jiménez-Vázquez Alexander , Vega Hermes , Alvarado Alexander , Mó Edgar
Published: March 2023

The first natural hybrid of the genus Gongora is described for the department of Copán in Honduras, between the species Gongora truncata and Gongora batemanii (synonym: Gongora cassidea). The nothospecies described here presents intermediate characteristics between both species, such as setaceous projections on the lip, a large callus, spatulate epichile, and a cucullate hard dorsal sepal. The identity of a specimen from the Herbarium Jany Renz Botanical Institute, University of Basel, Switzerland, corresponds to the same hybrid described here and erroneously determined as Gongora saccata, a synonym of Gongora seideliana, is considered. The clarification of the synonymy of Gongora saccata and relevant aspects regarding the pollination mechanisms and reproductive barriers of both parent species are also discussed.
Orchids of the Southern Cone (1830–2000) – Part II. The Philippi dynasty: Plantarum Novarum Chilensium and Catalogus Plantarum Chilensium
Authors: Ossenbach Carlos
Published: March 2023

Bernhard Eunom Philippi (1811–1852), his brother Rudolph Amandus Philippi (1808–1904), and the latter’s son Federico Philippi (1836–1910) must be considered the main actors in the history of the natural sciences in Chile between 1840 and 1910. While Bernhard was responsible for convincing the rest of his family to emigrate to Chile (and in fact, became the initiator of German immigration to southern Chile), Rudolph became the leading Figure in Chile’s scientific community, becoming the first director of the National Museum of Natural History, a post he held from 1853 to 1897. The description of many new orchid species in the series Plantarum novarum Chilensium (1856–1864) during this time is only one of his merits. His son Federico took over the direction of the Museum after his father’s retirement until he died in 1910. Catalogus plantarum Chilensium (1881) stands out among his numerous publications.
Microsporogénesis y ultraestructura de los granos de polen en la planta del cacao, Theobroma cacao (Malvaceae)
Authors: Rincón-Barón Edgar Javier , Torres-Rodríguez Gerardo Andrés , Cuarán Viviana Lucia , Carreño-Olejua René , Passarelli Lilian M.
Published: March 2023

Introducción: Estudios sobre la microsporogénesis de la planta del chocolate son inexistentes y poco se conoce sobre la ultraestructura de los granos de polen. Objetivos: se describe por primera vez y de manera pormenorizada el proceso de microsporogénesis, destacándose aspectos ultraestructurales de los granos de polen en T. cacao.  Métodos: Se procesaron más de 30 flores por cada uno de los estadios del desarrollo floral de acuerdo con los protocolos para embeber y seccionar en parafina. Las secciones obtenidas se tiñeron con Safranina-Azul de Alcian, PAS-Amidoblack y Lacmoid. Se procesaron muestras adicionales en resina y se tiñeron con azul de toluidina y se observaron secciones ultrafinas con microscopía electrónica de transmisión (TEM). Para la observación con microscopía electrónica de barrido (SEM), el material se fijó y deshidrató en 2,2 dimetoxipropano, luego se secó hasta un punto crítico y se recubrieron con oro. Resultados: las anteras se diferencian de una masa celular en los extremos distales de los filamentos estaminales. Durante el desarrollo la pared de las anteras presenta varios estratos celulares y al madurar se reducen a la epidermis y al endotecio. Las células madre de microsporas se dividen por mitosis y luego experimentan meiosis para formar tétrades. El tapete es secretor y se mantiene hasta antes de la liberación de los granos de polen, posteriormente degenera. Durante la formación de la esporodermis, primero se deposita la exina y luego la intina. Los granos de polen son isopolares, pequeños, esferoidales, tricolpados. La esporodermis es semitectada, con ornamentación reticulada, retículos heterobrochados, los muros sin ornamentación. Los orbículas son individuales, lisas y de diferentes tamaños. La ultraestructura muestra que los granos de polen son semitectados, la ectexina formada por tectum, columelas y capa basal que constituye la ornamentación reticulada y una endexina muy delgada y compacta. El polenkit es abundante sobre el tectum y entre las columelas. La intina es muy delgada, pero se desarrolla ampliamente en las zonas de los colpos formando una intina compacta interna y una inusual intina externa de apariencia columelada. Conclusión:  La estructura y desarrollo de las anteras sigue los patrones conocidos de las angiospermas. La microsporogénesis simultánea y el depósito centrípeto de la esporodermis se han descrito previamente para Malvaceae. Las características de la intina son novedosos para la familia.
Flowering time and harvest on floral morphology and production of hermaphrodite flowers in the cashew tree Anacardium occidentale (Anacardiaceae)
Authors: Pereira Jéssica Soares , DoVale Júlio César , Machado Ingrid Pinheiro , Melo José Wagner Silva , Vidal Neto Francisco das Chagas , Melo Dheyne Silva , Barros Levi de Moura
Published: March 2023

Introduction: Morphological parameters of flowering are fundamental in the reproductive process of plants, but this subject is poorly explored in the cashew tree Anacardium occidentale. Objective: To determine the influence of the flowering and harvest period on floral parameters, and to identify association with hermaphrodite flowers in the dwarf cashew. Methods: For the 2018 and 2019 harvests in 120 samples we measured number of male/hermaphrodite/abnormal flowers; panicle biomass, length, maximum width, and ramifications at 30, 45 and 60 days for 360 samples in total, for each season (2018 and 2019). Results: The harvest effect was not significant. Panicle length and width (at 30 days), had the greatest contributions to the production of hermaphrodite flowers. The presence of male flowers (at 45 days), and the panicle length and number of primary branches (at 60 days) were the main factors at their respective periods. Conclusions: The emission of hermaphrodite flowers responds negatively to male flowers. Variations in flowering compromise the production of hermaphrodite flowers and the flowering structure.
Determination of antioxidant, anticancer, antidiabetic and antimicrobial activities of Turkish red pine (Pinus brutia Ten.) bark ultrasound-assisted extract as a functional food additive
Authors: Erol K.F. , Kutlu G. , Tornuk F. , Guzel M. , Donmez I.E.
Published: March 2023

Turkish red pine (Pinus brutia Ten.) is an important tree species that grows widely in Türkiye. In this study, Box-Behnken experimental design was created and optimised for ultrasound assisted extraction of bioactive components of Turkish red pine waste bark. Extraction yield, total phenolic content (TPC), total concentrated tannin (TCT), ferric reducing antioxidant power (FRAP), and 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) were determined at experimental points. As a result of the optimisation process, optimum parameter values were found at 34.8 °C temperature, 6.5 min time and 116.3 W ultrasonic power. Under optimum conditions, the extraction efficiency was 13.16%, TPC 103.09 mg GAE/g, TCT 13.29 mg CE/g, FRAP 602.14 mg TEAC/g, and ABTS 624.51 mg TEAC/g activity results were obtained. The extracts obtained showed low in vitro toxicity against healthy cell lines (HEK-293, human embryonic kidney), proliferation of CaCo-2 (human colorectal adenocarcinoma) and MIA PaCa-2 (human pancreatic adenocarcinoma) cancer cells was significantly reduced. It was also determined that this extract has lower activity against Alzheimer's disease (AD)-associated AChE (acetylcholinesterase)-BChE (butyrylcholinesterase) than diabetes disease associated ɑ-glucosidase and ɑ-amylase. The extracts also showed significant antibacterial activity against Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes, Salmonella Typhimurium, and Escherichia coli.
Le culte de sainte Agathe entre Catane et Constantinople
Authors: Nonveiller Elena
Published: March 2023

This paper aims to examine some aspects of the history of the official cult of Saint Agatha in Sicily and Constantinople, starting with the Greco-Roman cults of Isis, and then focusing in particular on the unofficial or the initiatory women's festival, celebrated in Constantinople, attested by only one literary source from the 11th century AD. This source, consisting of a short philosophical treatise ascribed to Michael Psellos, informs us about some interesting aspects of the religious and social life of women in Constantinople in the mid-Byzantine era.
Hospital Chaplains as Interlocutors on Existential Themes with Patients at Risk of Suicide
Authors: Søberg Ane Inger Bondahl , Danbolt Lars Johan , Haug Sigrid Helene Kjørven , Sørensen Torgeir
Published: March 2023

This qualitative study focuses on how hospital chaplains encounter and explore existential themes in their conversations with patients at risk of suicide. Hospital chaplains from three of the four health regions in Norway participated in focus group interviews. The interviews were analysed by systematic text condensation. We found that the participants emphasized support and being a witness to patients’ narratives, exploring existential themes regarding life and death, guilt and shame, relatedness and loneliness, faith and hope. The chaplains understood their role as representing life. Their theological perspectives, pastoral clinical education and experiences were seen as being important in these conversations. Further research may investigate how the hospital chaplains’ role and existential competence can contribute to interdisciplinary teams working with patients at risk of suicide, examining how conversations about existential themes affect patients’ health, and whether these conversations prevent suicide.
Determination of the average size of preliminary grinded wet feed particles in hammer grinders
Authors: Abilzhanuly Tokhtar , Iskakov Ruslan , Abilzhanov Daniyar , Darkhan Orazakhin
Published: March 2023

In the conditions of farms, it becomes necessary to grind feed that has a different degree of moisture. Therefore, the choice of universal working bodies is the object of research, and the theoretical determination of the average size of pre-crushed feed particles is of great scientific and practical importance and is a problem that needs to be solved. Proceeding from this, a constructive-technological scheme of a grinder with a universal grinding working body is proposed. The grinding apparatus is equipped with a hammer working body which has cutting edges. In this case, hammers with cutting edges crush the wet mass, and also create an air flow and work as flow accelerators at high speed. As a result of theoretical studies, the steps for arranging these working bodies were determined. Analytical expressions are obtained for determining the average length of pre-crushed feed particles depending on the distance between the faces of replaceable knife working bodies, i.e. from the step of arranging them in rows. At the same time, the calculation results showed that with a distance between the faces of replaceable hammers of 20 mm, the value of the average length of the grinded particles was 38.38 mm. The average size of pre-crushed particles from feed raw materials intended for farm animals was 37.64 mm, i. e. the difference between theoretical and actual value is only 2.0 %. This proves the reliability of the obtained analytical expression, which provides the determination of the main parameter of the grinding working body, i. e. spacing of radial knives in rows. The proposed method of determining the average length of crushed particles allows theoretically finding and planning the required particle size
Selection of welding robot by multi-criteria decision-making method
Authors: Son Nguyen Hong , Hieu Tran Trung
Published: March 2023

Welding is a method to join parts together by a stable connection. Welding is used in many different fields. The limitations of manual welding methods are gradually eliminated when using welding robots. The selection of a welding robot has a great influence on the efficiency of the welding process. Choosers (customers) often encounter problems when choosing among many products that are available in the market. During this study, seven types of robots were given to make a choice including AR700, AR900, AR1440, AR1730, AR2010, MA3120, VA1400 II. These seven options are commonly used in welding processes. There are a variety of different parameters (criteria) used to evaluate each of these robots. However, the value of the criteria in the robots is very different. The selection of a robot that is considered the best should be based on all those criteria. At this point, the selection of robots is called MCDM (Multi-Criteria Decision-Making). In this research, two MCDM methods were used to rank the types of robots: MARCOS (Measurement of Alternatives and Ranking according to COmpromise Solution) and PSI (Preference Selection Index). The determination of important quantities for the criteria has been carried out by various methods, including the MEREC (MEthod based on the Removal Effects of Criteria), EQUAL, ROC (Rank Order Centroid) and RS (Rank Sum) methods. The MARCOS method was used four times corresponding to four different sets of weights. Meanwhile, when using the PSI method, we do not need to calculate the weights for the criteria. All five ranking results indicate the same best alternative. The results indicate that MA3120 is the best one. The two methods MARCOS and PSI are reliable enough to be used when multi-criteria decision-making is required, firstly, in the selection of welding robots.
Optimization of technical and technological indicators of kefir added with defatted sesame flour and rice bran
Authors: Qin Xuanxuan , Samilyk Maryna , Luo Yanghe
Published: March 2023

Defatted sesame cake and rice bran are all by-products of agricultural processing. The aim of the study was to optimize the recipes of kefir added with defatted sesame flour and rice bran. The previous study has yielded some results including dietary fiber content, pH values and sensory evaluation values of kefir samples added with 0, 2 %, 4 %, 6 %, 8 % DSC and 0, 0.1 %, 0.3 %, 0.5 %, 0.7 % RB, but made no optimization of kefir products. Based on these data, formulation optimization was done using a mathematical model. Two central composite designs for the two-factor analysis (x1x2 and x1x3, respectively) and one three-factor design (x1x2x3) were drawn up to predict the optimal formulation and reduce the number of future experiments. After studying the results of mathematical modeling, the optimal prescription composition corresponds to the 2 % DSC or 0.1 % rice bran content or 2 % DSC and 0.4 % RB content in the recipe. Through mathematical optimization, products with high dietary fiber content, suitable acidity and excellent sensory quality can be obtained. The products meet the current social demand for healthy food and have very good research value. In practical use, three kinds of kefir can be developed:
1. DSC should be ground separately before used, 2 % DSC was introduced into cow milk (m/v), fermented at 28°C for 22 h until pH reached 4.7, then stored at 4 °C;
2. RB should be ground before used, 0.4 % RB was introduced into cow milk (m/v), fermented at 28°C for 22 h until pH reached 4.7, then stored at 4°C; 
3. DSC and RB should be ground before used, 2 % DSC and 0.4 % RB were introduced into cow milk (m/v), fermented at 28 °C for 22 h until pH reached 4.7, then stored at 4 °C
Production of yogurt from goat and sheep milk with a fruit and berry concentrate
Authors: Velyamov Shukhrat , Ospanov Assan , Tlevlessova Dinara , Makeeva Raushan , Tastanova Raushan
Published: March 2023

The production and use of fruit and berry concentrates in combination with fermented milk products is attractive for many manufacturers because as a result it is possible to obtain unique recipes with a bright and attractive taste for consumers, and high functional properties. However, the use of fruit and berry concentrates in combination with fermented milk products leads to a reduction in the shelf life or absolute spoilage of products. Thus, after the initial analysis of modern technologies, the method of encapsulation of juice concentrates will create unique products – fruit and berry concentrates in the form of soft capsules for a safe combination with yogurt.
The creation of culinary delights of molecular cuisine is already using methods for preparing alginate capsules containing a juice-containing filler. However, there are no regularities for establishing a widespread production of capsules from alginate and a filler from the juice of fruits and berries to this day. In turn, it should be noted that this method makes it possible to obtain a product with high functional properties and pronounced taste.
The results of the research confirmed the successful possibility of mixing plant ingredients with yogurt and ultimately the possibility of obtaining a natural and healthy product with a pronounced and original taste.
The effect of capsules with fruit and vegetable extract on the organoleptic and structurally mechanical properties of yogurt was investigated. Recipes of fruit and berry concentrates were considered. In total, 3 varieties of one-component concentrates (apple, cherry, grape) were selected, which can be encapsulated in the alginate shell in their original form. 3 varieties of concentrates (raspberry, strawberry, currant) were obtained, which can be used as an additional component to the main ones to create a wide range of capsules for different age categories
Determining the influence of irradiation swelling on creep and damage in elements with orthotropic material properties
Authors: Breslavsky Dmytro , Mietielov Volodymyr , Tatarinova Oksana
Published: March 2023

This paper reports a method that numerically models the deformation and accumulation of hidden damage in structural elements that are in an inhomogeneous thermal field and are exposed to radiation. Materials considered are those exhibiting orthotropy (transversal isotropy) of long-term properties. The problem is stated as an boundary – initial value one. To solve it, the finite element method and the initial-difference method of time integration are used. To simulate the anisotropy of the process of accumulation of hidden damage, a damage tensor is applied. The development of irradiation swelling strains is described using the equation for a limited temperature range and a specific fluence value. The results of numerical modeling of creep and damage in plates in tension with circular notches, which are in an inhomogeneous temperature field, are considered. The material of the plates is a titanium alloy VT1-0. It was found that the effect of irradiation significantly, up to 6‒7 %, increases the level of deformation in the plate. Radiation significantly, by almost 4 times, reduces the time until the completion of the hidden fracture of the plates. It was found that orthotropy of radiation swelling properties leads to redistribution of areas with significant strains and damage values. It has been established that the effect of irradiation swelling also qualitatively changes the nature of the distribution of maximum damage in the plate, which extends to a fairly large area. Such results are due to the additional effect of irradiation swelling strains on the rate of general irreversible deformation and redistribution of stresses
Justification of the method for determining the dynamic parameters of the mobile fire fighting installation operator
Authors: Abramov Yuriy , Basmanov Oleksii , Sobyna Vitaliy , Kovalov Oleksandr , Feshchenko Andrey
Published: March 2023

The object of this study is the process of functioning of the "man-robot" system. The task to coordinate parameters of the human operator and the robot is investigated. Aligning these parameters is based on the method of determining the dynamic parameters of the human operator using mathematical models that describe two types of relative errors. The first type includes relative errors in determining the dynamic parameters of the operator, which depend on the error in determining the signals characterizing his response to the test impact. The second type of relative errors is the methodical error, which is due to the approximation of partial derivatives.
The formation of a test impact on the operator is carried out using an interactive whiteboard. The method is based on finding the roots of a linear system of algebraic equations, for the construction of which an approximation of partial derivatives from signals characterizing the operator's response to the test effect is used. The parameters of this system of algebraic equations depend on time parameters. Determination of time parameters is carried out using tolerance criteria and using nomograms. When justifying the main parameter of the test impact on the operator – the speed of movement of the fire front on the interactive whiteboard screen, the properties of the angular eye control system of the mobile fire installation operator are used. These properties are formalized as a mathematical model of dynamic error, which occurs in the process of tracking by the operator the image of a fire on the interactive whiteboard screen. To verify the obtained results, a test problem has been solved; it is shown that the error in determining the dynamic parameters of the operator does not exceed 1.0 %.
The results reported here could be used for designing mobile fire installations of a new generation, the structure of which is based on the use of segways
Analysis of compositions and fuel specifications of the aqueous emulsion fuels of gasoline (RON 90)-ethanol-water in stable emulsions at low temperatures
Authors: Sangian Hanny Frans , Pasau Guntur , Tamuntuan Gerald Hendrik , Widjaja Arief , Purwadi Ronny , Agnesty Silvya Yusnica , Sriana Tun , Nurrahman Arif , Tuhuloula Abubakar , Thahir Ramli
Published: March 2023

Many countries worldwide encounter the greatest difficulties in improving people's life quality since fossil fuel reserves are decreasing, causing fuel prices to rise drastically. This problem has made many countries, including Indonesia, struggle to import them from producers in the Middle East. Adding a small part of ethanol to gasoline is one of the solutions that has been investigated and developed.
The previous works relating to blended fuels, gasoline and ethanol, generally employed absolute alcohol, which was expensive. A small surfactant was added to the mixture to stabilize the emulsion, and the blending was conducted in normal conditions (room temperature). If the composition of gasoline and aqueous ethanol is not precise, the components can be separated at a specific temperature.
The present study is aimed to report the analysis of compositions and fuel specifications of aqueous emulsions of gasoline (RON 90)-ethanol-water in a single phase without using a synthetic surfactant in the temperature range of 0–25 °C. The procedures were as follows: fermentation, ethanol distillation and purification, cooling, blending, and characterization of fuel specifications. Components of gasoline (RON 90)-ethanol-water formed a stable emulsion in the composition range of 28.00‒99.79 %, 0.20‒67.97 %, and 0.01‒3.58 %. The observation found that continually increasing the amount of aqueous ethanol and temperature after one phase was attained would not lead to the separation of components. Therefore, gasoline and aqueous ethanol can form a single phase functioning as a surfactant binding water and fossil fuel. The decrease in temperature after the emulsion is stabilized can separate the components whereby it is caused by the faster density change of aqueous ethanol than gasoline
Revealing the peculiarities of average bicoherence of frequencies in the spectra of dangerous parameters of the gas environment during fire
Authors: Pospelov Boris , Andronov Vladimir , Rybka Evgenіy , Chubko Larysa , Bezuhla Yuliia , Gordiichuk Svitlana , Lutsenko Tatiana , Suriadna Nataliia , Hryshko Svitlana , Kushchova Tetyana
Published: March 2023

The object of this study is a change in the hazardous parameters of the gas environment when materials are ignited in the premises. The subject is the features of the average bicoherence of the frequencies of the spectra of changes in the hazardous parameters of the gas environment when materials are ignited. The importance of such studies is based on the fact that the examined features can be used for the early detection of fires. The value of the average bicoherence is proposed to be determined for each frequency, taking into account the average value of the cosine argument of the complex bispectrum for a given frequency interval. It was established that the values of the average bicoherence of the spectrum of changes in the temperature of the gaseous medium in the interval of no ignition of the materials, averaged by frequency in the range of 0–2 Hz, lie in the range from ‒0.052 to ‒0.35. At the same time, the frequency-averaged values of mean bicoherence at the ignition interval of materials lie in the range of ‒0.128 to +0.155. Averaged in the frequency range of 0–2 Hz, the value of the mean bicoherence of the spectrum of changes in smoke density in the interval of absence of ignition of materials lies in the range from ‒0.018 to +0.568. In the presence of fires, this value is in the range from –0.244 to +0.23. At the same time, the average value of the average bicoherence of the spectrum of changes in the concentration of carbon monoxide of the gas medium for test materials, averaged in the range from 0 to 2 Hz, ranges from +0.016 to +0.109. In the case of ignition of materials, the average values range from +0.0007 to +0.053, except for ignition of wood (+0.117). In general, the revealed features of the average bicoherence of the frequency components of the spectra of changes in the hazardous parameters of the gas environment indicate the possibility of their use to identify fires and prevent fires
Computer analysis of multiple measurements with the sensor's quadratic transformation function
Authors: Shcherban’ Volodymyr , Korohod Hanna , Chuprynka Nataliia , Kolysko Oksana , Shcherban’ Yury , Shchutska Ganna
Published: March 2023

The object of research is multiple measurements. The research aims to improve the accuracy of multiple measurements with a non-linear and unstable sensor transformation function. It is proved that the redundant measurement equation ensures the independence of the measurement result from the parameters of the transformation function and their deviations from the nominal values. It was found that the result of redundant measurements is affected by the reproduction errors of normalized temperatures T1 and T2. It is shown that the best accuracy results are obtained with a reproduction error of normalized temperature T2 within ±1.0 % and temperature T1 within ±0.1 %. This makes it possible to reduce the accuracy requirements for the source of reproduction of normalized temperature Т2.
The possibility of processing the results of multiple measurements by two approaches is presented. Computer modeling using the first approach found that with a reproduction error of normalized temperature T2 within ±0.5 %, the relative measurement error is 0.003 %. When modeling the second approach, the relative error is 0.05 %. It was also found that with an increase in the reproduction error of normalized temperature T2 to ±1.0 %, the value of the relative error is 0.04 %. Due to this, when applying the second approach, it becomes possible to choose a non-high-precision source of reproduction of normalized temperature T2. In addition, the sensitivity of the second approach to the digit range of measuring devices was found, which leads to the dependence of the measurement result on their accuracy.
There are reasons to assert the possibility of increasing the accuracy of multiple measurements by processing the results of intermediate measurements according to redundant measurement equations using two approaches
Developing microphone-based audio commands classifier using convolutional neural network
Authors: Mahdi Shakir Mahmood , Hussein Sabreen Ali , Salman Hayder Mahmood , Sfayyih Alyaa Hamel , Sulaiman Nasri Bin
Published: March 2023

Audio command recognition methods are essential to be recognized for performing user instructions, especially for people with disabilities. Previous studies couldn’t examine and classify the performance optimization of up to twelve audio commands categories. This work develops a microphone-based audio commands classifier using a convolutional neural network (CNN) with performance optimization to categorize twelve classes including background noise and unknown words. The methodology mainly includes preparing the input audio commands for training, extracting features, and visualizing auditory spectrograms. Then a CNN-based classifier is developed and the trained architecture is evaluated. The work considers minimizing latency by optimizing the processing phase by compiling MATLAB code into C code if the processing phase reaches a peak algorithmically. In addition, the method conducts decreasing the frame size and increases the sample rate that is also contributed to minimizing latency and maximizing the performance of processing audio input data. A modest bit of dropout to the input to the final fully connected layer is added to lessen the likelihood that the network will memorize particular elements of the training data. We explored expanding the network depth by including convolutional identical elements, ReLu, and batch normalization layers to improve the network's accuracy. The training progress demonstrated how fast the accuracy of the network is increasing to reach about 98.1 %, which interprets the ability of the network to over-fit the data of training. This work is essential to serve speech and speaker recognition such as smart homes and smart wheelchairs, especially for people with disabilities
Formation of economic and legal measures for the development of the market of intellectual property objects
Authors: Maslak Mariya , Pererva Petro
Published: March 2023

The problems of intellectual property market development have been investigated. It is proved that without the successful functioning of this market it is impossible to ensure the innovative development of the country. The characteristics of the intellectual property market, as well as the factors restraining its development, have been determined. The most important of them are significant volumes of outflow of Ukrainian scientists to foreign countries, low quality of Ukrainian patents, high level of counterfeiting and piracy, corruption pressure on the development and use of intellectual property, insufficient level of material support, etc. Therefore, the purpose of this study is to develop measures to strengthen the factors that contribute to the development of the intellectual property market and reduce the negative impact of factors on the Ukrainian technological market. To achieve the goal, it is proposed to introduce organizational and legal measures to improve the working conditions of employees of the main scientific institution of the country, the National Academy of Sciences (NAS) of Ukraine, the institutes of which produce most intellectual developments, as well as to form special financial and material mechanisms to support innovation at the expense of budget funds.
Using the example of reforming the institutes of NAS, according to the proposed measures, proposals have been formed to preserve scientific personnel, intensify the cooperation of scientific institutions with business, built on the interest of all parties in the field of technology commercialization. Counteraction to counterfeiting is proposed to be carried out taking into account a more accurate calculation of the commercial risks to which business entities are exposed in the manufacture and use of innovations. It is recommended to strengthen the level of legal protection of exclusive rights. Legislative initiatives on the development of the intellectual property market have been formed, which relate to changes in patent legislation regarding utility models and bringing it to EU conditions
A method for assessing the productivity trends of collective scientific subjects based on the modified PageRank algorithm
Authors: Andrashko Yurii , Kuchanskyi Oleksandr , Biloshchytskyi Andrii , Pohoriliak Oleksandr , Gladka Myroslava , Slyvka-Tylyshchak Ganna , Khlaponin Dmytro , Chychkan Ivan
Published: March 2023

The task of calculating the productivity of collective scientific subjects is a relevant issue in scientometrics. This study formalized the problem of assessing productivity trends of collective scientific subjects. The TWPR-CI method for calculating the performance based on the modified PageRank algorithm is described. Formulas for calculating productivity have been derived that make it possible to take into account a change in the productivity of collective scientific subjects over time. The indicators of the basic average absolute change in performance and the chain average relative change in performance were chosen as the basis. To select promising, from the point of view of scientific work, collective subjects, preference is given to those whose basic average absolute change in productivity is positive or the chain average relative change in productivity exceeds unity. Verification of the method for assessing performance trends of collective scientific entities based on the modified PageRank algorithm using the public dataset Citation Network Dataset was carried out. The dataset includes more than 5 million scientific publications and 48 million citations. The citation of scientific publications of 27,500 collective scientific subjects for the period from 2000 to 2022 was analyzed. For this period, for 15 selected collective scientific subjects, performance is calculated using the TWPR-CI method, as well as estimates of productivity trends based on their average relative change. There are three classes of collective scientific subjects according to productivity trends. The results indicate the relevance of the proposed method for quantifying the productivity trends of collective scientific entities (higher education institutions, scientific institutes, laboratories, and other institutions engaged in scientific activities)
Development of a cropping resilient watermarking scheme based on contourlet transform for secure IoT communication
Authors: Idham Yahya , Alsaydia Omar , Abdullah Mohammed A. M. , Mohammed Ahmed , Elbasi Ersin
Published: March 2023

The objective of this work is to propose a robust watermarking method as watermarking techniques are widely used today for preventing image altering and duplication. With the growth of image-based IoT applications nowadays, the need for developing robust digital watermarking techniques is of high demand. In this work, a robust yet highly perceptible watermarking scheme is proposed. The proposed scheme is based on the Contourlet Transform (CT) and Singular Value Decomposition (SVD) as the embedding domain in which the high-frequency components are chosen for embedding. The frequency domain is selected in order to make the watermarking scheme resists image attacks as the watermark is spreaded across different frequency bands in the cover image and hence the possibility of altering all the embedded bands is not possible as it will results in destroying the cover image. On the other hand, the Arnold transformation was used to insure secure IOT communication where the Arnold transform is applied to the binary logo watermark before embedding for a more secure design. In this context, the host image has been decomposed into the first level of contourlet transform and the highest frequency sub-bands are selected for embedding after performing the SVD on those bands where the SVD matrix is chosen to be the embedding domain. Moreover, This work aims to resist the cropping attack on images where PSNR values were above 52 dB and NC values ranged from 0.8 to 0.9 under various types of cropping attacks. In addition, the proposed method demonstrates its ability to resist various geometric and noise attacks such as JPEG compression, histogram equalization, gaussian noising and image brightening. Comparisons with state-of-the-art work demonstrate the proposed scheme's efficienc
Fatigue determination of the kenaf/PLA composite structure using fatigue specimen (ASTM D7791): a computational analysis
Authors: Abbu Muthana Adil Najim , Hashim Doaa Talib , Albegmprli Hasan Mohammed Ahmed , Mezaal Mustafa Ridha
Published: March 2023

In this investigation, a kenaf/PLA composite specimen was subjected to the fatigue load, and the results were analyzed numerically. Some of the most significant fatigue tool aspects that were looked into were life expectancy, damage, alternative stress, and biaxiality indication. The static structural tool was utilized in order to predict the numerical analysis, and the calculations were performed with the GoodMan theory of fatigue. The loading was completely reversed so that it was equal to 30 kN. When it was discovered that the system could continue to function even after 1e6 cycles had been completed. After applying the alternative load of 30 kN, the biaxiality indication was found to be 0.425, with a minimum value of 0.9. It has been determined how much damage has occurred. The minimum amount of cycles necessary to reach the maximum damage potential is 1000, while the maximum amount of cycles necessary to reach the maximum damage potential is 1.7662·106. It has been established that there is another stress that is comparable to this one. Based on the findings of the investigation, it was determined that the fillet regions of the specimen were subjected to a maximum alternative stress of 716.4 MPa. The alternative stress cannot drop below 31.276 MPa under any circumstances. It has been determined that 106cycles have been spent living in total by the calculation. It has been found out that there is not going to be any damage regardless of the number of cycles that pass due to the fact that that number is 1. It was found that the alternative stress could reach a maximum value of 716.4 MPa, so that was the value that was used for the alternative stress