bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determining the deformation properties of jacquard single jersey for pattern designing dresses, by the percentage of Elastane in the yarn
Authors: Peneva Tania P , Balabanova Diana R , Dolapchieva Galia G 
Published: February 2021

Abstract
The article presents a method for determining for deformation properties of knitted fabrics in the process of pattern making of women’s outerwear, by the percentage of elastomeric threads in their composition. To develop the method, a study of the deformation properties of a group of jacquard single jersey fabrics was performed, depending on their content of elastomeric threads. A model for their determination in the process of clothing design pattern through reduction factors is proposed. The dependence on the reduction factors and the percentage of elastomeric threads in the composition of the knitted fabrics was studied. Strong statistically significant dependences were found. Using the method of linear regression, mathematical models have been developed, by which the reduction factor is determined on the basis of the percentage of elastomeric threads in the knitted fabrics. The obtained results are applied to improve the methodology for pattern designing women’s dresses.
An application of analytical data research in e-learning system
Authors: Orozova Daniela , Hristova Nely 
Published: February 2021

Abstract
Algorithms for extracting information from big data today are very useful in e-learning systems. The main functions of these algorithms are the application of various methods to detect and retrieve models of stored data. Different machine learning techniques are used and rules for association, classifications, clusters, etc. are derived. Open knowledge is used to make predictions about: admission of students in a particular course, forecasting grades in online tests, finding inaccurate grades, predictions for graduation of students and more.
Accelerometer-based human activity recognition using 1D convolutional neural network
Authors: Tsokov S , Lazarova M , Aleksieva-Petrova A 
Published: February 2021

Abstract
Human activity recognition (HAR) is an important research field with a variety of applications in healthcare monitoring, fitness tracking and in user-adaptive systems in smart environments. The performance of the activity recognition system is highly dependent on the features extracted from the sensor data which makes the selection of appropriate features a very important part of HAR. A 1D CNN model trained on accelerometer data is suggested in the paper for automatic feature extraction in a HAR system. A semi-automatic approach is used that effectively and efficiently determines the number of convolutional layers in the network, the number of kernels and the size of the kernels. The experimental results show that the suggested model outperforms several existing recognition approaches that use the same data set.
Action model of Angiotensin II receptors on smooth muscle ileum preparations
Authors: Vasilev M D , Yankov K B 
Published: February 2021

Abstract
This paper presents an approach using control theory methods to monitor the effect of Angiotensin II (Ang II), AT1 and AT2 receptor subtypes on the visceral smooth muscle in ileum preparations. Since AT1 and AT2 are involved in feedback during the regulatory action of Ang II, it is convenient to block them with a suitable antagonist. In this way, three transients were obtained, which were identified by a second-order differential equation. The individual identification vector was calculated for each of the processes. The analysis of the models showed that when the PD 123319 blocker was applied, the amplitude of the responses to smooth muscle contractions increased. From this, it can be concluded that the AT2 type receptors have an AT1 antagonistic effect during the contractile process.
Algorithms for optimizing packet propagation latency in software-defined networks
Authors: Ivanov I G , Hristov G V , Stoykova V D 
Published: February 2021

Abstract
With the development of technology in recent years, it is clear that the potential in traditional networks has been exhausted. Software defined network (SDN) is emerging network, which provides a global centralized view, separating the control plane from the data plane. This article discusses the potential for determining the optimal latency in SDN networks with capital cost optimization-CapEx. A mathematical formulation for solving the problem is considered. Following this approach will speed up routing and improve QoS.
On Convolutional Neural Networks for Chest X-ray Classification
Authors: Naskinova I 
Published: February 2021

Abstract
Pneumonia is an infectious disease accounting for one fifth of the deaths of children under five worldwide. It is also a cause for adult hospital admissions with mortality rate of almost 25% in patients over 75 years. Pneumonia is curable and mortality can be prevented if it is diagnosed. Preferred diagnostic technique is chest X-ray image examination. The lack of radiology equipment of trained clinicians reduces the chance of the majority of people to be properly diagnosed. In the paper we propose a shallow convolutional neural network architecture, further fine-tuned with chose of the Adam optimizer which is split tested in the current experimental work. We showed that the automatic detection of pneumonia in chest X-ray images is possible with accuracy higher than 90% using 3 blocks of 2 convolutional 2D layers with max-pooling for feature extraction and a flatten output block comprising two dense layers, trained over 10 epochs. Therefore, the application for CNN is a viable solution as a supplement to the decision-making process of pneumonia X-ray diagnostics.
Phytochemical composition of leaves and stems of Solanum nigrum L. and Solanum dulcamara L. (Solanaceae) from Bulgaria
Authors: Popova V T , Stoyanova M A , Ivanova T A , Stoyanova A S , Dimitrova-Dyulgerova I Z 
Published: February 2021

Abstract
The objective of this study was the determination of certain phytochemical indices (cellulose, protein, amino acids, ash, minerals) of the leaves and stems of two Solanum species, S. dulcamara L. and S. nigrum L., collected from their natural habitats in Bulgaria. Both species, naturally occurring in many regions of Bulgaria, are important plants in folk medicine and fall under the regulations of the Medicinal Plant Act. The analysis of cellulose, protein and ash content in the dried leaves and stems revealed differences on a plant part basis. Stems contained higher amounts of cellulose (S. dulcamara, 29.4%; S. nigrum, 39.2%) than the leaves (14.9% in both species). The stems of S. nigrum contained nearly twice as much protein than the leaves (15.3% vs 8.1%); the ratio was reversed in S. dulcamara (12.3% vs 21.3%). The dominant macroelements in S. dulcamara were K (25925 and 14514 mg.kg-1, respectively in the leaves and stems), Ca (3588 and 326 mg.kg-1) and Mg (2561 and 308 mg.kg-1). In S. nigrum, the same macrominerals showed relatively less variation on a plant part basis. The dominant microminerals were Fe, Zn and Mn; reasonably, higher concentrations were found in the leaves. The dominant amino acids in S. dulcamara leaves were phenylalanine, glutamine, asparagine, tyrosine, and serine (2.2-2.5 mg.g-1); in the stems-proline (7.3 mg.g-1), alanine (7.2 mg.g-1), asparagine (5.0 mg.g-1), and lysine (4.6 mg.g-1). The dominant amino acid in S. nigrum leaves and stems was asparagine, 5.0 mg.g-1 and 20.6 mg.g-1, respectively. The results supported the assumption that the studied aerial parts contained valuable phytochemicals, which could provide grounds for their practical use in specific areas, such as human and animal nutrition, cosmetics, phytopharmacy or others.
Application of biomass from Greek juniper needles (Juniperus excelsa M. Bieb) for removal of Cr (VI) from aqueous solution
Authors: Nikolova M I , Prokopov T V , Stankov S S , Bozadzhiev B V , Stoyanova A S 
Published: February 2021

AbstractThe main goal of present study was to examine the performance of biomass from Greek juniper needles(Juniperus excelsaM. Bieb), obtained after distillation of the raw material, for its ability to remove Cr (VI) ions from aqueous solution. The used biomass was characterized by FT-IR analysis. Batch experiments were conducted and the effects of different biosorption process parameters were determined. Maximum removal efficiency (99.58 ± 0.31 %) was obtained at pH = 1.0, adsorbent dose 0.5 g L-1, agitation speed 250 rpm, initial Cr (VI) concentration 50 mg L-1, temperature 30.0 ± 1.0°C and contact time of 30 min. The pseudo-second order model was found to provide the best fit to experimental kinetics data (R2= 1.000) and the calculated value of equilibrium metal uptake agree quite well with the experimental value. Results indicated that the Freundlich (R2= 0.975) and the Langmuir (R2= 0.976) isotherm models correlated very well to the experimental equilibrium data for Cr (VI) removal. Finally, the applied biomass could be used as a cheap biosorbent for the removal of Cr (VI) ions from aqueous solutions with high maximum adsorption capacity (qmax = 143.0 mg g-1), compared to other biosorbents reported in the literature.
Study of the changes in the chemical composition of Bulgarian dill essential oils
Authors: Dobreva K Z , Dimov M D 
Published: February 2021

Abstract
The chemical composition and therefore the quality of essential oils can vary depending on several factors like the time of harvest, the location of the crop, the part of the plant, the geographical and climatic conditions as well as the production method. The aim of this work is to study the change in the composition of the Bulgarian dill essential oils of known origin during the different harvest years and its storage. Plant parts of dill (Anethum graveolens L.) from the region of village Gavrailovo, Bulgaria were investigated. Significant qualitative and quantitative differences in the chemical composition of the studied oils and the data in the literature were detected. It has been established that the essential oils from the herb and the fruits of the dill in the region of village Gavrailovo contains significant amounts of methyl chavicol (32,90 – 62,96 %) which is the reason to be considered as a new methyl chavicol chemotype.
Edible coatings enriched with Malva sylvestris L. extract
Authors: Alexieva I N , Baeva M R , Popova A T , Petrova I V , Fidan H N , Milkova-Tomova I V , Mihov R B 
Published: February 2021

Abstract
Edible coatings can play a leading role in food storage. In baked goods, attention is focused on inhibiting the processes of mold development and moisture loss. Adding functional ingredients to coatings can slow the spoilage process thus increasing shelf-life. The purpose of this study was to prepare edible coatings with polysaccharides and coconut oil enriched with an ethanol extract of Malva sylvestris L. flowers (mallow) and to characterize its physico-chemical and antibacterial properties. A computerized method for analysis of the digital dispersions images was used to further describe the enriched coatings. The rheological characteristics of the coatings were determined by structural mechanical analysis. All developed model emulsion coatings demonstrated a polydisperse character-the diameter of the globules in the studied volume ranged from 1.5 μm to 12 μm. All enriched coatings with mallow extract had better dispersion characteristics. The results showed that the presence of a mallow extract had a positive effect on the antibacterial activity of the xanthan food coating by increasing the zone of inhibition against Escherichia coli ATCC 8739. The pectin coating with mallow extract exhibited antibacterial activity against Salmonella NCTC 6017, while a suppressive effect on tests pathogen did not characterize the control sample.
Application of information and communication technologies and simulators to train future specialists in navigation and ship handling
Authors: Danylenko O B , Soroka O M , Dukov D F , Soshnikov S G , Kramarenko V V 
Published: February 2021

Abstract
The article presents the experience of using information and communication technologies and simulators in training future specialists in navigation and ship handling in maritime institutions of higher education. During the research a wide range of information and communication technologies and training tools were used in order to simulate scenarios of professional activity, emergency situations that are as close as possible to real conditions. The study was conducted from May 2015 to May 2019. The academic disciplines were enriched with separate components of simulator-based training for developing skills to work with electronic mapping systems, radio and electronic navigation equipment of ships, as well as skills related to maritime safety. Academic disciplines were delivered both in specialized laboratories equipped with the necessary training equipment and information and communication technologies in accordance with international requirements for training of marine specialists and the employers’ requirements, and also the training process included e-learning technologies. Comparison of research data before and after the experiment indicates a positive impact of information and communication technologies and simulators on the quality of training future specialists in navigation and ship handling.
Review on assessment of corrosion of mild steel in alkaline environment by using plant extract
Authors: Baitule P K , Victoria S N , Manivannan R 
Published: February 2021

AbstractMany industries face corrosion caused by the alkaline medium. There are various techniques to minimize the corrosion such as anodic protection, cathodic protection, coatings and green corrosion inhibitor. To minimize the effect of corrosion in an alkaline medium, green technology i.e. green corrosion inhibitor has been widely used. Natural plant-based extract is used as green corrosion inhibitor to mitigate the problem of corrosion. It is naturally occurring, non-expensive, safe and ecologically acceptable. The plant origin extract contains tannins, alkaloids, organic, amino acids which are main functional groups in mitigating the corrosion. The present review paper summarizes the various plant-based green corrosion inhibitor used for minimizing the corrosion of mild steel in an alkaline medium. Also, the plausible mechanism for the inhibition of corrosion in alkaline medium is explained comprehensively.
Dynamic Stability Investigation of a Sandwich Beam Tapered along width and thickness with Temperature Gradient
Authors: Pradhan Madhusmita , Nayak Dipesh Kumar , Dash Pusparaj 
Published: February 2021

Abstract
The investigation to analyze a sandwich beam's dynamic stabilitywith asymmetric configuration, tapered along the thickness and width, and influenced by an alive axial load with temperature gradient is executed for several boundary conditions employing computational method. Use of Hamilton’s principle results in the equations of motion and related boundary conditions. Hill’s equations are achieved using non-dimensionalized equations of motion with the Galerkin’s method. Then, the influence ofseveral parameterson the dynamic stability for different boundary conditions are attained by applying Saito-Otomi conditions. The impact of differentparameters on the regions of instabilities observed and is showcased in a sequence of graphs using the appropriate MAT LAB program.
Modeling of two link manipulator used for 3D printing
Authors: Navaneetha K , Anjaneya Prasad B , Bhargavi M , Singaravel B 
Published: February 2021

Abstract
Additive manufacturing/Rapid prototyping is one of the emerging areas in the field of Mechanical Engineering. 3D printing is also known as additive manufacturing. It is a latest and interesting technology used for developing a 3- dimensional solid object from a digital model. Fused Deposition Modeling (FDM) is one of the additive manufacturing techniques used with three linear axes for producing components. A two link (revolute) manipulator consists of two joints separated in space by the links. It provides planned trajectory by programming and relationships between joint variables. The idea of the present paper is to replace and analyze the three mutually perpendicular linear axes of FDM with two link (revolute) manipulator. The complete dimensional, mass data along with the maximum size of the manufacturing component and work volume are selected from the existing FDM. Two link (Revolute) manipulator, work volume and nozzle are modeled in Computer Aided Design (CAD) software. The results have shown that the proposed two link (Revolute) manipulator is used to reduce the number of motors involved in the existing FDM.
Application Of Energy Harvesting In The Field Of Mechanical Vibrations
Authors: Behara Naga Sudha Rani , Rao Prof. Putti Srinivasa 
Published: February 2021

Abstract
Energy harvesting (EH) is the most upcoming technology which is defined as a process where the environmental energy sources such as load, mechanical vibrations, temperature changes, light energy, wind energy etc. are captured and transformed to acquire quite small levels of power within the of range of Nano Watts - Milliwatts. This method is used to power an installed system by accumulating energy from ambient sources such as solar, wind, thermal and radio frequency waves. It is also called Energy Scavenging. The purpose of energy harvesting is to power electronic devices where there are no conventional power sources. The energy harvesting device has design goals and the three main elements are energy Source, Energy harvesting IC, Energy storage. In particular the energy harvesting used in charging of rechargeable batteries on site, low power electronic devices like traditional and super capacitors. Common energy harvesting systems include a lot of applications in many remote locations, distant locations, undersea where batteries and conventional power are not in used practically. In this paper the research that has been carried away in the field of energy scavenging of vibration analysis was discussed. In this scenario different type of energy harvesting methods like Thermo electric harvesting, Piezo electric energy harvesting, Pyro electric Energy Harvesting, PVDF Films are studied and focused on the method which is relatively used to enhance the performance and transformation efficiency in the analysis of vibrations. From all the above methods the piezo electric energy harvesting is the one which is suitable for analysis of vibration since the deflection of a specimen using piezo electric material results in an electric displacement. This electricity can be used in storage of power in batteries or used to power portable devices.
Dynamic Mechanical Analysis of 3D Printed PETG Material
Authors: Subbarao Ch V , Srinivasa Reddy Y , Inturi Vamsi , Indra Reddy M 
Published: February 2021

Abstract
3D printing technology through fused filament fabrication has found various industrial applications in the field of rapid manufacturing to fabricate prototypes and concept models. However, being the most popular technology, fused filament fabrication requires through understanding about the influence of the process parameters on resulting products. This investigation attempts to provide the terse behavior of the viscoelastic properties of fused filament fabrication processed with Poly Ethylene Terephthalate Glycol (PETG) samples considering the impact of fused filament fabrication process parameters. Dynamic mechanical analyzer is used to perform the dynamic mechanical analysis (DMA) and the dynamic response of fused filament fabrication PETG specimens is studied while they are subjected to dual cantilever loading under periodic stress. The fused filament fabrication process parameters such as, feed rate, layer thickness and infill density are considered. PETG parts are fabricated using 100% infill density at a feed rate of 50 mm/sec with three different layer thicknesses of 0.17 mm, 0.23 mm and 0.3 mm. DMA is performed with temperature ranging from room temperature to 130°C at five different frequency values of 1 Hz, 2 Hz, 5 Hz, 7 Hz & 10 Hz. The effect of process parameters of fused filament fabrication and frequencies on the viscoelastic properties of 3D printed PETG specimens is explored. The results reveled that, the storage module and loss module values are better for the specimens prepared with a layer thickness of 0.17 mm irrespective of the variation in the frequency values.
Experimental Investigations on Schleichera Oleosa (SO) based biodiesel operated Indirect injection (IDI) diesel engine for Performance Enhancement and Reduction in Emissions
Authors: Ranjit P S , Kamesh Vinjamuri Venkata , Saravanan A , Dash Santosh Kumar , Bhurat Swapnil Sureshchandra , Sreeramulu Mahesh G 
Published: February 2021

Abstract
With India's demographic demand for more energy on the one hand and its deficit imports much oil to meet its demand, it is placing India under enormous economic sanctions. Exponential extraction and pollution of fossil fuel inspire and motivates researchers and scientists to explore the various alternatives. Schleichera Oleosa based biodiesel is one such fuel of its physical and chemical characteristics near conventional diesel to investigate its performance and emissions of the 4S, water-cooled, naturally aspired IDI CI engine. The same findings were also compared with the SO straight vegetable oil and conventional diesel operation. Biodiesel output based on Schleichera Oleosa is similar to diesel operations with marginal pollution penalties.
Use of Nahar biodiesel-diesel blend in a agricultural diesel engine
Authors: Dash S K , Das P K , Ranjit P S , Kumar A , Papu N H , Lingfa P 
Published: February 2021

Abstract
This paper presents the features of a non-edible feedstock Nahar oil derived B15 blend of Nahar biodiesel powered single cylinder DI diesel engine. Various output parameters such as thermal efficiency of the engine, specific fuel consumption and temperature of the exhaust gas; different emission parameters such as specific CO, specific HC, NOx, smoke opacity and combustion parameters such as ignition delay have been studied. The experimental investigation reveals that the thermal efficiency slightly reduced. At highest load, the BTE for the blend is 31.56% and for the diesel it is 32.49%. All pollutant emissions significantly reduced, and ignition delay also reduced for the B15 blend. CO and HC emission observed to be 3.11 and 0.035 g/kWh. Overall, it is suggested to use Nahar biodiesel blend as a diesel supplement in engine.
Weight optimization of Piston using CREO parametric and ANSYS
Authors: Ravikiran MSSR , Prasad Saidge Akhil , Srujana Vaddepally , Abhhimanyu Korlepara Shanmukh Sai 
Published: February 2021

Abstract
The Piston is a crucial element of an I.C engine. The Piston is a reciprocating component of the I.C engine that converts thermal energy and pressure energy liberated by the ignition of the air-fuel into mechanical work. The design of the Piston and selection of material is a challenging assignment for the designer. This paper describes the design procedure for a piston of a four-stroke petrol engine. The optimization of Piston with different materials was carried out in the present work. The analysis is done by considering two designs, one is primary, and the other is an optimized one. The modelling is achieved by utilizing the Creo parametric and further investigation in ANSYS workbench. The design process involves the evaluation of varied piston measurements using the analytical technique at the maximum power condition. While computing various aspects, the cumulative impact of mechanical stress and thermal distribution are considered. Three different materials are considered for designing the Piston, and their performances are scrutinized. The Aluminium cast alloy is the most used in manufacturing the pistons. However, the analysis done in this project has given better results for Aluminium Silicon Carbide. All the results for it have turned out to be better than the Aluminum Cast alloy.