bluuebunny/crossref_metadata_2025 huggingface dataset:
The Use of the Powtoon Application in Learning Videos for Elementary School Students
Authors: Pratiwi Melly Siska , Zulherman  , Amirullah Gufron
Published: February 2021

One of the learning media that needs to be developed is the powtoon application-based learning media. This basic concept puts the idea of the teaching and learning process using animated videos. The purpose of this research is to determine the results of the powtoon application-based learning process in science lessons about energy, in fourth grade elementary schools. The use of this media is very effective during these times because when the researcher began her research about the usage of this media, home learning was being carried out due to Coronavirus outbreak (Covid-19), so the teaching and learning process was carried out using the internet. The research method used survey method of research, using the ADDIE development model. The learning media test was carried out by 3 media experts, 3 subject experts and 3 teachers from different schools. The product trials were conducted by 79 students from three different schools. The data was collected using the Likert scale with a range of score from 1 to 5. The results of this research show that the powtoon application-based learning media is very good for teaching and learning in schools about energy in elementary schools, because the Powtoon application is able to develop students’ imagination and common sense in learning thus increasing their learning achievement. Further research by combining learning strategies during the pandemic through online learning.
Examining Resource Based Learning and Individual Learning Capabilities in Todays’ Scenario
Authors: Sadasivan Usha , Balachander Bhuvaneswari , Vijayalakshmi S.
Published: February 2021

The immense use of web based resources is an undeniable truth in today’s learning scenario. Resource-based learning has gained momentum in leaps and bounds. Resource-based learning aids in the academic and holistic development of students by taking into account their capabilities, their styles of learning and their needs. RBL empowers the student to analyze and organize digital material. It also enables the learner to develop critical thinking skills and gives them the confidence to sift from the plethora of information available, the skill to ferret out what they need and what is needed for them. This skill will go a long way in empowering them to utilize the varied resources that is available on hand in various forms be it print or electronic. Such training in thinking will help them to approach any topic in a number of learning styles. The authors of this research paper, have attempted to understand the impact of resource based learning on teachers, keeping in view Gagne’s (1985) theory of levels of learning. Teachers from traditional background of teaching methods involving classroom interface, were approached and their views on the new methods popularized by RBL were obtained by means of a self-administered online questionnaire. The objective of the study was to analyze the attitudinal responses of the teachers towards RBL and whether they viewed it as a beneficial exercise for students as against traditional methods of learning.
Application of Learning Using Online Media During the New Normal
Authors: Jasiah  , Rakhman Arif , Arifin Ardian , Safitri Riana , Perdana Indra , Khaidir Abdul Wahab M.
Published: February 2021

The purpose of this research is to be able to know the implementation of learning during the New Normal period, the readiness of educators in carrying out learning activities and to find out how distance learning activities are carried out in middle schools and colleges, especially whether this learning can be achieved or not. In order to obtain the desired data, this study uses a survey method. The data that has been received will be carried out by quantitative descriptive analysis. In this study, primary data types were taken by taking individual or respondent responses as many as 121 respondents from West Kalimantan Province, both from private and public schools or colleges. The results of this research are the provision of learning materials using online learning media that have been carried out by educators showing various kinds of obstacles used by educators and the use of social media is the most widely used as well as presentation-based learning media and Youtube videos. The achievement of learning outcomes in online learning in the New Normal Era was not significant because there were still challenges faced by educators.
Eating healthy or wasting less? Reducing resource footprints of food consumption
Authors: Helander Hanna , Bruckner Martin , Leipold Sina , Petit-Boix Anna , Bringezu Stefan
Published: February 2021

To feed future populations on ever-scarcer natural resources, policy initiatives aim to decrease resource footprints of food consumption. While adopting healthier diets has shown great potential to reduce footprints, current political initiatives primarily address strategies to reduce food waste, with the target of halving food waste at retail and consumption levels by 2030. Using Germany as a case study, we compare the resource-saving potential of this political target with three scenarios of nutritionally viable, plant-based dietary patterns and investigate interactions and trade-offs. By using the Food and Agriculture Biomass Input–Output model, we capture biomass, cropland, and blue water footprints of global supply chains. The results show that dietary changes are particularly effective in reducing biomass and cropland footprints, showing a decrease of up to 61% and 48%, respectively, whereas halving food waste decreases biomass and cropland footprints by 11% and 15%, respectively. For blue water savings, halving food waste is more effective: water use decreases by 14% compared to an increase of 6% for dietary change with the highest water consumption. Subsequently, a combination of the scenarios shows the highest total reduction potential. However, our findings reveal that despite reduced footprints, a dietary shift can lead to an increased amount of food waste due to the rising consumption of products associated with higher food waste shares. Therefore, policy strategies addressing both targets might be contradicting. We conclude that international and national policies can be most effective in achieving higher resource efficiency by exploiting the reduction potentials of all available strategies while simultaneously considering strategy interactions.
Characterising port-based teleportation as universal simulator of qubit channels
Authors: Pereira Jason , Banchi Leonardo , Pirandola Stefano
Published: February 2021

Port-based teleportation (PBT) is a teleportation protocol that employs a number of Bell pairs and a joint measurement to enact an approximate input-output identity channel. Replacing the Bell pairs with a different multi-qubit resource state changes the enacted channel and allows the PBT protocol to simulate qubit channels beyond the identity. The channel resulting from PBT using a general resource state is consequently of interest. In this work, we fully characterise the Choi matrix of the qubit channel simulated by the PBT protocol in terms of its resource state. We also characterise the PBT protocol itself, by finding a description of the map from the resource state to the Choi matrix of the channel that is simulated by using that resource state. Finally, we exploit our expressions to show improved simulations of the amplitude damping channel by means of PBT with a finite number of ports.
Assessment of the risk of poisoning by combustion products from domestic gas-fired appliance using CFD modeling
Authors: Czerski G , Śpiewak K
Published: February 2021

Gas-fired appliances, including water heaters, are widely used in households and may have a significant impact on their gas atmosphere, i.e. reduction of oxygen concentration and appearance of toxic oxides (especially CO). Therefore, the paper deals with the assessment of the risks of poisoning by combustion products from a gas appliance using CFD modeling. A three-dimensional numerical CFD (Computational Fluid Dynamics) model of a real apartment was developed, in which the gas-fired instantaneous water heater with a standard power of 20 kW works in the bathroom. The model enabled the performance of transient simulation calculations for various air inflows (ventilation) to the abovementioned apartment (30 - 120 m3/h) as well as for various concentrations of carbon monoxide in combustion gases (0.1 - 1%). It was assumed that combustion gases inflow entirely into the room for 10 minutes. Based on the calculations performed, it was shown that the main threat occurs in the room where gas-fired water heater is located, i.e. in the bathroom. Moreover, changes in concentration of carbon monoxide and oxygen over time, and depending on the room height, were analysed. In addition, an analysis of the impact of combustion gases inflow on the temperature in the bathroom and the whole apartment was made.
Polluted Landfill adaptation into agricultural soil: heavy metal phytoremediation with Indian Black Mustard (Brassica Nigra) and Dolomitic Lime Fertilizer.
Authors: HariharaSudhan C , Anuradha B , Jayadevsivani S , Gokul K
Published: February 2021

Bio-medical and electronic waste accumulation from industry and anthropogenic sources is deposited at landfill sites over the years, possessing waste degradation into heavy metal deposition in soil such as Cd, Ni, Pb, which is detrimental to the developing embryo development and affects respiratory function. The hyper-accumulator herb, such as Indian mustard ( Brassica Nigra), which was able to absorb heavy metals from the soil and water and wipe out soil after a period of time and disposed of it. Dolomitic Lime Fertilizer is a Inorganic compound derived from mixture of calcium carbonate (caco3) and magnesium carbonate (mgco3) are used for the sustained agriculture. The Extraction of heavy metals along with Dolomitic lime helps to increase the nitrogen fixation rate in soil and reduce the acidity nature of the soil also acts as a soil conditioners. They provide eco-friendly, cheap and renewable resource for the subsequent years. Phytoremediation of contaminated sites is requires low cost and more renewable compared to remediation strategies that involve removing polluted soil constituents.
Experimental Investigation of Recycled Coarse Aggregates on Partial Replacement of Cement with Silica Fume
Authors: Manivel S , Pannirselvam N , Rajprasad J , Hemanarayanan T.S.
Published: February 2021

Coarse aggregate utilized majorly in concrete to reach the ultimate quantity in larger proportion. The structural and non-structural elements in the construction utilize majorly the concrete. Due to the mass availability of concrete during the demolition process and hence absorbing the same material to replace the coarse aggregate with recycled aggregate is the emerging field and it is sustainable. The experimental work involving the replacement of coarse aggregates with recycled aggregates and cement with silica fumes to improve the properties of concrete and eliminate the difficulties in construction field paves way for the further researches. The experimental study concentrates in the strength properties of the concrete with recycled aggregates and silica fume and compared with the conventional concrete.
Study of Fibre Reinforced Concrete Using Sustainable Materials
Authors: Uma Maguesvari M , Muthaiyan P , Yugasini S , Ammaiappan M
Published: February 2021

Our current generation is a pillar of this developing world in construction field, which also leads to decrease in natural raw materials and increase in production of many industrial waste materials creating an impact to living life through flaming and landfilling. Concrete is one of high production material in our daily life and have most probable way to substitute the waste materials. In this present work waste material are used for replacement of materials in developing the fibre reinforced concrete. Workable and mechanical characteristics of fibre reinforced concrete have assessed by substitution of coarse aggregate with recycled aggregate at(0%,10%,20%,30%, and 40%), and fine aggregate as M- sand, waste foundry sand and bottom ash and binder is replaced with silica fume 7% in addition to that fibre content as 0%,0.5%,1% and 1.5% of micro steel fibre and Basalt Fibre by weight of cement. Workability decreases with rise in incorporation of recycled aggregate and also it diminishes workability with the inclusion of fibres. The concrete mixture with replacement of coarse aggregate including micro steel and basalt fibre content have exhibited higher mechanical strength.
Experimental Study On Partially Replaced Concrete With Automobile Industries Wastes
Authors: Kalpana Ms.M. , Sudharson Mr.G.
Published: February 2021

In recent days, the major threat to our environment is waste management. As a contribution to save our environment many research works are happening to utilize waste in their manufacturing process to reduce waste as well as reducing the cost involved in the process. Waste utilization will partially help us to protect our environment. In this paper, for manufacturing concrete with partially replaced fine aggregate is experimented. The objective is to reuse the locally available polypropylene fibre generated as waste by automobile industries. The adhesion between polypropylene fibre and cement matrix is considered as an important factor. To give proper matrix between the fibre and cement, shredded polypropylene fibre is used as partially replaced fine aggregate. The replacement percentages used are 20%, 40% and 60%. The specimens were prepared with water cement ratio 0.5 and tested after 7days and 24 days of curing period. The influences of polypropylene fibre in concrete in fresh and hardened state are compared with conventional concrete properties. The results obtained shows increase in the strength and workability property for 20% replacement of polypropylene fibre as fine aggregate in concrete. Hence the disposal of polypropylene waste from automobile industry can effectively be used in shredded form as partial replacement of fine aggregate in concrete.
A multibody model of a wheel loader with pneumatic boom suspension and proving ground testing
Authors: Pavlov N L , Dacova D I
Published: February 2021

In this paper a multibody dynamic model of a wheeled tractor-front-end loader system with pneumatic boom suspension is created. A front-end loader was designed and manufactured to validate the dynamic model and to conduct proving ground tests. Comparisons of some simulation results with the measured data revealed that the proposed dynamics model can well describe the vibrations of the tested compact wheel loader. In addition, the results of tests for RMS acceleration and spectral densities at different speeds are presented.
Solutions for increasing the comfort in road vehicles based on improving the construction of the seats
Authors: Pavlov N L , Dacova D I
Published: February 2021

To reduce the harmful vibrations to which passengers and drivers are exposed when traveling in road vehicles, various suspension systems for the vehicle, chassis or seats may be used. Most research and development is focused on reducing vertical vibrations. When the vehicle is cornering, lateral acceleration occurs, which causes discomfort to passengers. According to a number of studies, the value of lateral acceleration can be reduced if the vehicle or seats lean towards the center of the turn. This study looks at some solutions to increase comfort in road vehicles based on improving the design of the seats. New design solutions for a child tilting seat, which were developed by the authors, are presented. Road experiments have been carried out to demonstrate that the use of these seats when the vehicle is cornering can reduce the value of lateral acceleration.
NDVI, chlorophyll and carotenoids content of leaves of Rosa damascena Mill under organic and conventional farming
Authors: Todorova M , Petkova N , Grozeva N , Gerdzhikova M , Lazarova S , Lozanova L , Mladenov A
Published: February 2021

The aim of our study was to compare NDVI index, total nitrogen, chlorophyll and carotenoids content of leaves of oil-bearing roses cultivated under organic and conventional agricultural systems in order to find impact of farm management on the physiology status of Rosa damascena leaves. The experiment was conducted on six private arable areas with Rosa damascena Mill in Rose valley, Southern Bulgaria. The selected study area size was 5000 m2 from each private territory. Three of the oil-bearing rose plantations are certified as organic farming and have been applied an organic agriculture system and the rest of them are characterized as conventional farming. NDVI index of the leaves of Rosa damascena was measured with Plant Pen 310 device in the field. The same leaves were picked up for future laboratory analysis. The total chlorophyll and carotenoids, μg/g dw content of leaves in the 80 % acetone were determined, total nitrogen by Kjeldahl method as well. Linear discriminant analysis (LDA) was performed to classify Rosa damascena leaves on the base of NDVI and photosynthetic pigment content according to relevant farm management. The results from conventional rose bushes leaves contained statistically proven higher total chlorophyll and lower total carotenoids than leaves belonging to organic oil-bearing roses cultivation. It is worthwhile to continue investigations with NDVI leaves measurements as a promising tool for recognition organic or conventional farm production.
3D printing on warp-knitted fabrics
Authors: Ayvali M , Bussieweke L , Druzinin G , Korkmaz M , Ehrmann A
Published: February 2021

While 3D printing was in former times mostly used for rapid prototyping, nowadays it is also used for rapid manufacturing. To overcome the problems of relatively low production speed and in several cases insufficient mechanical properties of 3D printed objects, 3D printing can be combined with larger-scale production processes, e.g. by directly printing on textile fabrics. To combine the advantages of both materials, e.g. tensile strength of a woven fabric with stiffness of an imprinted layer, the adhesion between both partners under mechanical load has to be investigated. Here, we use tensile tests to examine maximum forces, elongation at break, wearing out of the composites and the adhesion under maximized or repeated tensile stress to examine the applicability of such composites for sports shoes etc.
Method of optimization of geometric transformations of design surfaces of a man’s jacket
Authors: Slavinska A L , Mytsa V V , Syrotenko O P , Dombrovska O M
Published: February 2021

The article considers the mechanism of combining 3D and 2D-design methods based on the combination of modules of 3D-digital modification of the morphological structure of the body and 2D-generation of sweep details of the jacket. The mechanism of formation of the integrated design system for transformation of a surface of a body into silhouette designs on the basis of geometrical modeling has been offered. The selection of optimal divisions of the mannequin surface on the basis of identification of zones of stable deformations of the grid with regular topology is theoretically substantiated. Has been shown that the maximum compression deformation in the range of overall dimensions characterizes the parametric levels of darts in the product design. The affine transformations by the operation “shift” of the mannequin surface scan into three basic silhouettes of the jacket design were experimentally investigated. Parametrical transformation of silhouette designs have been realized by schemes of designs and the reference book of standard movements. Homogeneity of details’ construction of the sketch project of interchangeable models system has been estimated by coefficients of constructive homogeneity of silhouette designs and technological homogeneity of model functional knots. The algorithm of formation of the integrated design system of 3D and 2D-design is developed and its practical application on an example of the development of a series of interchangeable models of a jacket is shown.
A study on pattern making of sleeves with curved shoulders
Authors: Kazlacheva Zlatina , Radieva Krasimira
Published: February 2021

The paper presents a study on pattern making of a constructional base for designing of sleeves with rounded shoulders for ladies’ dresses and jackets: kimono, raglan, semi raglan and sloped shoulders ones. The developed constructional model gives possibilities of facilitating and correct pattern making of a base of design of ladies’ dresses and jackets sleeves with curved shoulders: kimono, raglan, semi raglan and sloped shoulders ones. The use of obtained dependence between additional height in the rounded shoulders and the additional height in the armhole makes the geometrical sequence of pattern making easier. A similar study can be made for ladies’ outerwear.
Research on the relation between the percentage of elastomeric threads in the yarn and the stretch of punto di roma jersey
Authors: Peneva Tania P , Balabanova Diana R , Dolapchieva Galia G , Krastev Krasimir
Published: February 2021

The last few years have shown a tendency for an increase in the production of knitting fabrics made of yarns containing elastomeric threads. A main point of the construction of such garments is the determination of their deformation properties, which change depending on the type of the knit and the composition of the yarn. Determining these properties requires textile testing which takes time and requires additional expenditures which necessitates the development of new methods for their evaluation. The aim of this work is to examine the relation between the distortion features of elastic knit fabrics and the percentage of elastomeric threads in the yarn. The subject of the study is a group of knit fabrics with the Punto di Roma stitch structure containing elastomeric threads from 2% to 6%. Based on the proven statistical significance of the correlation coefficients, a regression analysis was performed. A mathematical model of the studied dependence is presented, regression equations are derived. The analysis of the model proved that it works. The results obtained from the study aim to optimize a method for constructing a garment from a knitted fabric containing elastomeric threads.
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

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

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

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

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

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

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

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

The 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

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

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

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

Many 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

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

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

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

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

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

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

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.
Performance & Emission Characteristics of Diesel Engine fueled with Bio-Diesel along with Additives (NM, MTBE)
Authors: Ravula Eshwaraiah , Saikumar Cherku , Mahender Bonakurthi , Adarsh Bachewale , Vijayaraj S , kumar Shiva
Published: February 2021

The significant quantity of power is expensive in transportation segment & industrial sector and also a critical command in meeting through CI engine in all over the world due to their greater performance as contrast to the conventional diesel fuels. However, there was a tremendous alarm regarding the crude oil products which are going to be depleted in near future. So, in this connection it is necessary to reach, the suitable fuels other than the fossil fuels and also on the other hand it is mandatory to control the expense of the both fuels. In this work an attempt is to be made to investigate the commercial use of suitable and non-toxic additives in order to improve the performance of an engine without sacrificing the functionality parameters. The main concern of this work is to utilize the maximum effective way to control the asserted parameters like emissions and combustion characteristics. This investigation carried out on a diesel engine fuelled with B100 (jatropha) with two additives, Nitro methane (Nm) and Methyl Tetra Butyl Ether (MTBE) are tested in kirloskar computerized diesel engine. Jatropha bio-diesel is a biodegradable, non-toxic, renewable fuel, environment friendly and do not build on globalwarming. Additives selected are based on the biodiesel characteristics, and economic feasibility. Additive MTBE is used for oxygenated and the other additive Nm is used as cetane booster.