bluuebunny/crossref_metadata_2025 huggingface dataset:
Hypolimnetic Aeration: An Overview
Authors: McQueen D.J. , Lean D.R.S.
Published: March 2019

Hypolimnetic aerators are now being widely used throughout Europe and are beginning to appear in small and medium sized eutrophic lakes in temperate North America. This activity has produced approximately 42 published reports dealing with experiments conducted at 16 lakes. Taken together, the evidence from these experiments suggests that well designed aerators do not cause significant destratification or warming of hypolimnetic water, but do result in measurable Increases in hypolimnetic oxygen concentration and decreases in dissolved hydrogen sulfide, methane and ammonia. Early experiments suggested that phosphorus sedimentation was unpredictable, but recent work has demonstrated that when the ratio of total iron to soluble reactive phosphorus exceeds 10:1 and pH is < 7.5, phosphorus sedimentation is assured and internal loading greatly reduced. Early experiments also showed that ammonia volatilization was unpredictable, but at pH > 8.0, ammonia volatilization will occur. Because both phosphorus sedimentation and nitrogen reduction are pH dependent, both cannot be optimally removed during the same period of time and so the experimenter is advised to select for the maximum removal of one or the other through pH manipulation. Hypolimnetic aeration induces oxygen consumption and this must be considered when choosing an appropriate compressor size. Most studies show little impact on phytoplankton blomass, but one recent experiment showed that aeration during spring turnover resulted in reduced concentrations of chlorophyll a and TP. Zooplankton populations are, for the most part, unaffected and a number of American studies have shown that hypolimnetically aerated lakes can support cold water fish populations. The aggregate practical and experimental experience suggests that well designed hypolimnetic aeration systems yield measurable improvements in water quality and will almost certainly prove to be one of the major methods used for future in situ lake restoration.
Anaerobic and Aerobic Treatability of High-Yield Sulphite Spent Liquor
Authors: Schnell A. , Hall E.R. , Skog S.
Published: March 2019

Several higher-yield sulphite pulp mills in Canada discharge untreated spent cooking liquor containing substantial amounts of dissolved organic pollutants. The Wastewater Technology Centre has conducted a study on the chemical characterization and biotreatability of spent liquor from a high-yield sulphite (HYS) and an ultra-high-yield sulphite (UHYS) pulping operation. Batch bioassays revealed a high degree of aerobic treatability, including filterable COD removals of 60-65% and 70–75% from HYS and UHYS waste liquor, respectively. Anaerobic treatment was found to be much less suitable as evidenced by severely inhibited methane production rates and impaired treatment efficiencies during batch serum bottle testing of 5-20% v/v spent liquor. Anaerobic bioassays over a 70-day incubation period with 5% HYS waste liquor produced relatively low filt-COD and filt-BOD5 removals of 30% and 75%, respectively. Even poorer performance results were observed at increased test concentrations. Although the degree of anaerobic treatment was somewhat better for the lower-strength UHYS liquor, a high level of dilution (i.e., 10-20 fold) was still required. The elevated concentrations of total sulphur and particularly sulphite-sulphur of 13.5 and 4.8 g/L respectively in HYS spent liquor, and of 3.6 and 1.3 g/ L in UHYS liquor, were apparently responsible for much of the toxic effects on the unacclimated anaerobic biomass.
Technical Review of Methods to Enhance Biological Degradation in Sanitary Landfills
Authors: Warith M.A. , Sharma R.
Published: March 2019

Biological processes are known to reduce the organic fraction of municipal solid waste, but current landfilling practices have not been altered to reflect this knowledge. The advantages of enhancing degradation of solid waste are as follows: reduced period of leachate treatment, increased methane production, expedited landfill site reclamation through stabilized waste mining, and accelerated subsidence permitting recovery of valuable landfill air space. The techniques that can be used to enhance biological degradation include leachate recirculation, addition of nutrients, shredding, sludge addition, lift design, temperature and moisture content management. Manipulation of these variables promotes a more conducive environment for microbial activity. Research on landfill management strategies through laboratory and full-scale studies has shown the validity of applying the enhancement techniques with regards to reducing leachate strength and increasing methane production. These practices focus on the use of landfills as bioreactors, which enables long-term flexibility and assures compliance with future regulations and discharge standards.
Tamarix articulata (T. articulata) - An Important Halophytic Medicinal Plant with Potential Pharmacological Properties
Authors: Alnuqaydan Abdullah M. , Rah Bilal
Published: March 2019

Background:

Tamarix Articulata (T. articulata), commonly known as Tamarisk or Athal in Arabic region, belongs to the Tamaricaece species. It is an important halophytic medicinal plant and a good source of polyphenolic phytochemical(s). In traditional medicines, T. articulata extract is commonly used, either singly or in combination with other plant extracts against different ailments since ancient times.

Methods:

Electronic database survey via Pubmed, Google Scholar, Researchgate, Scopus and Science Direct were used to review the scientific inputs until October 2018, by searching appropriate keywords. Literature related to pharmacological activities of T. articulata, Tamarix species, phytochemical analysis of T. articulata, biological activities of T. articulata extracts. All of these terms were used to search the scientific literature associated with T. articulata; the dosage of extract, route of administration, extract type, and in-vitro and in-vivo model.

Results:

Numerous reports revealed that T. articulata contains a wide spectrum of phytochemical(s), which enables it to have a wide window of biological properties. Owing to the presence of high content of phytochemical compounds like polyphenolics and flavonoids, T. articulata is a potential source of antioxidant, anti-inflammatory and antiproliferative properties. In view of these pharmacological properties, T. articulata could be a potential drug candidate to treat various clinical conditions including cancer in the near future.

Conclusion:

In this review, the spectrum of phytochemical(s) has been summarized for their pharmacological properties and the mechanisms of action, and the possible potential therapeutic applications of this plant against various diseases discussed.
Plant Thaumatin-like Proteins: Function, Evolution and Biotechnological Applications
Authors: de Jesús-Pires Carolline , Ferreira-Neto José Ribamar Costa , Pacifico Bezerra-Neto João , Kido Ederson Akio , de Oliveira Silva Roberta Lane , Pandolfi Valesca , Wanderley-Nogueira Ana Carolina , Binneck Eliseu , da Costa Antonio Félix , Pio-Ribeiro Gilvan , Pereira-Andrade Genira , Sittolin Ilza Maria , Freire-Filho Francisco , Benko-Iseppon Ana Maria
Published: March 2019

Thaumatin-like proteins (TLPs) are a highly complex protein family associated with host defense and developmental processes in plants, animals, and fungi. They are highly diverse in angiosperms, for which they are classified as the PR-5 (Pathogenesis-Related-5) protein family. In plants, TLPs have a variety of properties associated with their structural diversity. They are mostly associated with responses to biotic stresses, in addition to some predicted activities under drought and osmotic stresses. The present review covers aspects related to the structure, evolution, gene expression, and biotechnological potential of TLPs. The efficiency of the discovery of new TLPs is below its potential, considering the availability of omics data. Furthermore, we present an exemplary bioinformatics annotation procedure that was applied to cowpea (Vigna unguiculata) transcriptome, including libraries of two tissues (root and leaf), and two stress types (biotic/abiotic) generated using different sequencing approaches. Even without using genomic sequences, the pipeline uncovered 56 TLP candidates in both tissues and stresses. Interestingly, abiotic stress (root dehydration) was associated with a high number of modulated TLP isoforms. The nomenclature used so far for TLPs was also evaluated, considering TLP structure and possible functions identified to date. It is clear that plant TLPs are promising candidates for breeding purposes and for plant transformation aiming a better performance under biotic and abiotic stresses. The development of new therapeutic drugs against human fungal pathogens also deserves attention. Despite that, applications derived from TLP molecules are still below their potential, as it is evident in our review.
Malaria Hybrids: A Chronological Evolution
Authors: Marella Akranth , Verma Garima , Shaquiquzzaman Md. , Khan Md. Faraz , Akhtar Wasim , Alam Md. Mumtaz
Published: March 2019

Malaria, an upsetting malaise caused by a diverse class of Plasmodium species affects about 40% of the world’s population. The distress associated with it has reached colossal scales owing to the development of resistance to most of the clinically available agents. Hence, the search for newer molecules for malaria treatment and cure is an incessant process. After the era of a single molecule for malaria treatment ended, there was an advent of combination therapy. However, lately there had been reports of the development of resistance to many of these agents as well. Subsequently, at present most of the peer groups working on malaria treatment aim to develop novel molecules, which may act on more than one biological processes of the parasite life cycle, and these scaffolds have been aptly termed as Hybrid Molecules or Double Drugs. These molecules may hold the key to hitherto unknown ways of showing a detrimental effect on the parasite. This review enlists a few of the recent advances made in malaria treatment by these hybrid molecules in a sequential manner.
Review: Phytochemicals of the Seriphidium, Economically and Pharmaceutically Important Genus of Asteraceae Family
Authors: Shafiq Nusrat , Shafiq Sahrish , Rafiq Naila , Parveen Shagufta , Javed Irum , Majeed Humara Naz , Mahmood Ayesha , Noor Nadia , Anjum Abrar
Published: March 2019

Seriphidium plants were reported to be utilized by local communities to cure their ailments
in the form of paste, tincture, tea, nutraceuticals due to their medicinal properties. Most of the species
are used as food, forage and ornamentals, etc. Due to the significant properties of the Seriphidium
plants, the present article was designed to compile the data of major aspects and chemical constituents
of genus Seriphidium responsible for their significant uses. This review article comprehensively
covers the biological potential of different plants with their secondary metabolites and describes an
overview of the biological activities of the different species belonging to genus Seriphidium. The
main secondary metabolites isolated from different species of the genus Seriphidium are triterpenoid,
sesquiterpenes, flavonoids, coumarins, chromones, anthraquinones, polyphenols and their glycosides,
phenolic derivatives, balchanins, costunolides, Vulgarin, pyridine derivatives, ceramides, biphenyls,
isoflavones. All these compounds are used in the drug industry.
Development of Radiofrequency Saturation Amplitude-independent Quantitative Markers for Magnetization Transfer MRI of Prostate Cancer
Authors: Huang Xunan , Schurr Ryan N. , Wang Shuzhen , Miao Qiguang , Li Tanping , Jia Guang
Published: March 2019

Background:

In the United States, prostate cancer has a relatively large impact on men's health. Magnetic resonance imaging (MRI) is useful for the diagnosis and treatment of prostate cancer.

Introduction:

The purpose of this study was to develop a quantitative marker for use in prostate cancer magnetization transfer (MT) magnetic resonance imaging (MRI) studies that is independent of radiofrequency (RF) saturation amplitude.

Methods:

Eighteen patients with biopsy-proven prostate cancer were enrolled in this study. MTMRI images were acquired using four RF saturation amplitudes at 33 frequency offsets. ROIs were delineated for the peripheral zone (PZ), central gland (CG), and tumor. Z-spectral data were collected in each region and fit to a three-parameter equation. The three parameters are: the magnitude of the bulk water pool (Aw), the full width at half maximum of the water pool (Gw), and the magnitude of the bound pool (Ab), while, the slopes from the linear regressions of Gw and Ab on RF saturation amplitude (called kAb and kGw) were used as quantitative markers.

Results:

A pairwise statistically significant difference was found between the PZ and tumor regions for the two saturation amplitude-independent quantitative markers. No pairwise statistically significant differences were found between the CG and tumor regions for any quantitative markers.

Conclusion:

The significant differences between the values of the two RF saturation amplitudeindependent quantitative markers in the PZ and tumor regions reveal that these markers may be capable of distinguishing healthy PZ tissue from prostate cancer.
Brain Tissue Segmentation from Magnetic Resonance Brain Images Using Histogram Based Swarm Optimization Techniques
Authors: Thiruvasagam Priya , Palanisamy Kalavathi
Published: March 2019

Background and Objective:

In order to reduce time complexity and to improve the
computational efficiency in diagnosing process, automated brain tissue segmentation for magnetic
resonance brain images is proposed in this paper.

Methods:

This method incorporates two processes, the first one is preprocessing and the second
one is segmentation of brain tissue using Histogram based Swarm Optimization techniques. The
proposed method was investigated with images obtained from twenty volumes and eighteen volumes
of T1-Weighted images obtained from Internet Brain Segmentation Repository (IBSR), Alzheimer
disease images from Minimum Interval Resonance Imaging in Alzheimer's Disease (MIRIAD)
and T2-Weighted real-time images collected from SBC Scan Center Dindigul.

Results:

The proposed technique was tested with three brain image datasets. Quantitative evaluation
was done with Jaccard (JC) and Dice (DC) and also it was compared with existing swarm optimization
techniques and other methods like Adaptive Maximum a posteriori probability (AMAP),
Biased Maximum a posteriori Probability (BMAP), Maximum a posteriori Probability (MAP),
Maximum Likelihood (ML) and Tree structure K-Means (TK-Means).

Conclusion:

The performance comparative analysis shows that our proposed method Histogram
based Darwinian Particle Swarm Optimization (HDPSO) gives better results than other proposed
techniques such as Histogram based Particle Swarm Optimization (HPSO), Histogram based Fractional
Order Darwinian Particle Swarm Optimization (HFODPSO) and with existing swarm optimization
techniques and other techniques like Adaptive Maximum a posteriori Probability
(AMAP), Biased Maximum a posteriori Probability (BMAP), Maximum a posteriori Probability
(MAP), Maximum Likelihood (ML) and Tree structure K-Means (TK-Means).
Antioxidant, Antitumor and Bactericidal Activities of Ethyl Gallate Quinoxalines
Authors: Lima Rafaely N. , Gonçalves Jaqueline R. , Silva Valdenizia R. , de S. Santos Luciano , Bezerra Daniel P. , Soares Milena B.P. , Leitão Andrei , Porto André L.M.
Published: March 2019

Background:

Quinoxaline, a fused heterocycle of benzene and pyrazine rings are becoming
recognized as a potent class of anti-cancer compounds, such as, in a wide array of pharmacological
activities.

Methods:

We evaluate the three gallate quinoxalines (G-A1, G-A2, and G-A3) as c-Met kinase inhibitors
using a docking study, in vitro anticancer potential measurements, antioxidant and bactericidal activities.

Results:

The docking study showed hydrogen bond linkage of quinoxalines with amino acids at active
site of c-Met kinase structures, indicating a possible cancer inhibition cell proliferation. Therefore, the
three quinoxalines were analyzed against four in vitro cancer cell lines, and G-A1 demonstrated cytotoxicity
against HL-60 and HCT116 cell lines (IC50= 9.55 and IC50= 16.67 μmol L-1, respectively). In
HepG2 and MCF-7 cells, the IC50 were 22.48 and 33.42 μmol L-1, respectively. For G-A2 and G-A3,
cytotoxic activity ranged from 61.22 to >101.21 μmol L-1. Potent antioxidant activities were also obtained
for G-A2>G-A1>G-A3 (IC50= 4.5-8.4 μmol L-1 and AAI= 8.8-17.8). Six different Bacillius
strains showed growth inhibition (11.33 to 13.33 mm) in the presence of quinoxaline G-A1 (500 μg).

Conclusion:

The present work showed the biological potential of quinoxalines G-A1, G-A2 and G-A3
in inhibiting four cancer cells proliferation, in addition to a very strong antioxidant activity.
Combined Effects of Thermal Radiation and Magnetohydrodynamic on Peristaltic Flow of Nanofluids: Applications to Radiotherapy and Thermotherapy of Cancer
Authors: Hasona Wahed , Almalki Nawal , ElShekhipy Abdelhafeez , Ibrahim Mohamed
Published: March 2019

Background:

Cancer is deadly to most of its patients. Consequently, researchers and modelers studies show that there are many ways to cure and destroy it. One of the effective ways is to inject the blood vessel close to the tumor with magnetic nanoparticles. Another way called the radiation therapy or radiotherapy, which eradicates cancer cells through high doses of radiation.

Objective:

This paper opts to investigate the influences of thermal radiation and variable electrical conductivity on peristaltic flow of Carreau Nanofluids. First order chemical reaction, Dufour and Soret effects are taken into consideration.

Methods:

The resulting system of partial differential equations is solved numerically with the aid of Parametric-NDSolve. Results for velocity, temperature and concentration distributions are obtained in the analytical two-dimensional and three-dimensional forms. The streamlines graphs are offered in the terminus, elucidating the trapping bolus phenomenon.

Results:

It has been found that thermal radiation is a decreasing function in the temperature of the fluid. As the temperature decreases, the diameter of the nanoparticles increases i.e., the volume of nanoparticle and its concentration increases and become more effective near tumor tissues.

Conclusion:

Radiotherapy and Thermotherapy are effective methods to cure and damage the tumor tissues.
Dynamic Sliding Mode Control Based on Fractional Calculus Subject to Uncertain Delay Based Chaotic Pneumatic Robot
Authors: Gholipour Sara , Shandiz Heydar Toosian , Alizadeh Mobin , Minagar Sara , Kazemitabar Javad
Published: March 2019

Background & Objective:

This paper considers the chattering problem of sliding mode control in the presence of delay in robot manipulator causing chaos in such electromechanical systems. Fractional calculus was used in order to produce a novel sliding mode to eliminate chatter. To realize the control of a class of chaotic systems in master-slave configuration, a novel fractional dynamic sliding mode control scheme is presented and examined on the delay based chaotic robot. Also, the stability of the closed-loop system is guaranteed by Lyapunov stability theory.

Methods:

A control scheme is proposed for reducing the chattering problem in finite time tracking and robust in presence of system matched disturbances.

Results:

Moreover, delayed robot motions are sorted out for qualitative and quantitative study. Finally, numerical simulations illustrate feasibility of the proposed control method.

Conclusion:

The control scheme is viable.
Spectral Efficient and Reliable Irregular QC-LDPC Channel Coding Scheme for 5G Vehicular Applications
Authors: Arora Komal , Singh Jaswinder , Randhawa Yogeshwar Singh
Published: March 2019

Background and Objective:

Today’s wireless systems i.e. 4G systems are facing major
issues of spectral inefficiency, and unreliability for high speed applications. To address these issues,
5G systems have chosen LDPC codes and replaced earlier used Turbo Codes for the purpose of
Channel encoding. This paper proposes a design method for Irregular QC- LDPC codes with better
spectral efficiency and reliability that too at higher speed.

Methods:

This paper describes the analysis of LDPC codes and their comparison with different encoding
techniques. Also, it describes the design method for Irregular QC- LDPC codes and elaborates
its applications in high-pace vehicular 5G scenario.

Conclusion:

This paper focuses on the design method for irregular QC-LDPC codes and using
MATLAB simulations illustrated that these codes have better reliability and spectral efficiency as
compared with conventional LDPC codes in high-speed environments.
Grammatical errors of writing in EFL class
Authors: Latupeirissa David Samuel , Sayd Anastasia Imelda
Published: March 2019

The current paper is descriptive qualitative research which aimed at describing grammatical errors of students’ writing in English as a Foreign Language (EFL) Class. Data were gained from documents written by students of State Polytechnic in Kupang City, East Nusa Tenggara- Indonesia. The results have shown that the highest percentage of grammatical errors occurred in using the verb group. It consisted of 65.0 %. Following these errors, students made errors in the use of prepositions (12.8 %). The third errors that were usually made by students were the errors in the use of pronouns. It took 9.8 %. After errors in the use of pronouns, students made errors in pluralization (5.1 %). The next lower frequency of errors made by students were errors in the use of articles. It took 4.3 % of the whole text. Following that, students made errors in the use of conjunctions. The errors occurred at 1.7 %. The last errors made by students were errors in the use of subject-verb agreement. The errors occurred only 1.3 %. The results of the current analysis are hoped to be a reflection of EFL lecturers in Indonesia. Furthermore, EFL lecturers of State Polytechnic Kupang are hoped to focus more on teaching the use of verbs in writing class.
Simulation modelling in the sizing of city logistics systems – a study for concentrated delivery points
Authors: Bóna Krisztina , Sárdi Dávid
Published: March 2019

Nowadays, urban freight traffic is causing significant noise and air pollution, so it is in the focus of green logistics developments, both in technology and system organization. Based on experiences within city logistics, significant problems are caused by the so-called concentrated sets of delivery points, where there are several delivery points with heavy freight traffic in a relatively small area. Since the summer of 2015, we collected lots of data about stores of these delivery points to support the modelling and the simulation of the new green solutions for the examined city logistics systems. Based on our results we can say, there are significant savings in these systems, so it is worth to deal with developing new, gateway-concept-based and consolidation-based solutions.
Surface activation of High Impact Polystyrene substrate using dynamic atmospheric pressure plasma
Authors: Juhász Gergely , Berczeli Miklós , Weltsch Zoltán
Published: March 2019

Over the last decade, the number of researches has increased in the field of bonding technologies. Researchers attempt to improve surface adhesion properties by surface treatments. Adhesive bonding is one of these bonding techniques, where it is important to see what surfaces will be bonded. One such surface property is wetting, which can be improved by several types of surface treatment. In recent years, atmospheric pressure plasmas have appeared, with which research is ongoing on surface treatments. In our research, we will deal with the effects of plasma surface treatment at atmospheric pressure and its measurement. In addition, we summarize the theoretical background of adhesion, surface tension and surface treatment with atmospheric pressure plasma. Our goal is to improve adhesion properties and thus the adhesion quality.
Development of Efficient Drive Based on Self-help
Authors: Németh Géza , Péter József
Published: March 2019

The efficiency and the life rating are essential characteristics of mechanical drives. The traction drives with proper geometry can avoid the geometrical slip and their efficiency can exceed that of the gear drives. The elements has hardened steel surfaces, the lubricant is rheopectic. There is no danger for thinning the oil film and consequently for connecting the asperities. The traction drives are relatively noiseless, they are applicable for increasing speed in particular. There are some problems to be solved in friction drive. This is the necessity of clamping force. A simple machine element usually make a constant clamping force, a tensioning mechanism can be too complicated. The ideal solution is a simple design which assure a clamping force that is proportional to the instantaneous external load requirements. The authors suggest a modified machine element – a helical torsion spring, an elastic one, instead of the original, rigid annular wheel – that comprises both the driving and clamping functions, and the latter one is proportional to the external load, so that the principle of self-help operates.
Analysis of Vibration During Turning Process of Different Materials
Authors: Sarankó Ádám , Kalácska Gábor , Keresztes Róbert
Published: March 2019

In this article, we would like to introduce the problems caused by vibrations in case of polymer turning processes. Nowadays there is a lot of research in this topic, to avoid the unnecessary phenomena of vibrations. The two most common methods are the Spindle Speed Variation (SSV), and the Vibration Assisted Machining (VAM). In case of SSV, the CNC machine can increase and decrease the speed of spindle continuously during turning which can significantly reduce the effects of chatter. This method is beneficial for longer workpieces when there is not any support except the chuck. Vibration-assisted machining can be used to minimise the problems caused by vibrations. VAM combines precision machining with small-amplitude tool vibration to improve the fabrication process. It has been applied to some processes ranging from turning, drilling to grinding. Based on the enumerated above we made some trial measurements about the basic vibrations of the turning tool shank. The tests were done on an NCT EUROturn-12B CNC machine which can found in the workshop of our institute. The tested material was Polyamide 6 because this is the most commonly used polymer in the industry. In the future, we would like to test some other basic and composite polymer materials too. The equipment was served by a specialist from SPM Budapest Kft. With these tests, our goal was to make sure that the equipment and the measuring setup are suitable for our future research.
Testing of Micro Switches for Garden Tools
Authors: Sipkás Vivien , Bodnár Gabriella
Published: March 2019

The aim of this paper is to introduce the design of testing method for the prediction of the life and acceleration methods of the micro switches applied in different type of garden tools. These products will be tested for complex stressing, for example higher temperature, humidity, current load and so on. Therefore, the most important information and multi-factor acceleration models are summarized, the Weibull, the lognormal and the exponential distributions which are suitable for performing and evaluating tests.
The Mechanical Properties of 3D Printed CuZn28 Brass Specimens with Different Orientations
Authors: Szakál Zoltán , Kári-Horváth Attila , Pataki Tamás , Odrobina Miklós
Published: March 2019

In this paper, the properties of CuZn28 brass raw material were presented. The 3D printed metal specimens are made from this material with different orientations. Their mechanical properties (tensile strength, yield strength) and elongation were investigated according to MSZ EN 6892-1: 2012 standard. The strength of the different printing directions is analyzed and it is determined which printing direction is the most favourable. Finally, the effect of the different printing directions upon the structure of the material is studied.
Introduction to Design and Analysis of Torsional Vibration Dampers in Vehicle Industry
Authors: Venczel Márk , Veress Árpád
Published: March 2019

The crankshaft of today’s internal combustion engines with high performance output are exposed to harmful torsional oscillations originated from the unbalanced gas and inertial forces. To avoid the fatigue damage of engine components, caused by the undesired vibrations, torsional vibration dampers can be applied. Viscodampers are one type of the torsional vibration dampers, which operational fluid is silicone oil. For cost-effective R&D activities and production, finite element and finite volume numerical discretization methods based calculation techniques must be involved into the engineering work supported by the modern computer technology. The aim of this paper is to provide an insight into the multidisciplinary design and development process of visco-dampers in vehicle industry applications. Four different examples as structural, fatigue, CFD analyses and structural optimization have been introduced in the present work. It turned out from the static structural and fatigue analyses, that the investigated damper has safety factor over the limit for both static structural and fatigue analyses, so it is suitable for the given load conditions. In the structural optimization process 34.36% mass reduction has been achieved. According to the coupled fluid dynamic and heat transfer simulations a rather stagnating air zone evolved between the engine and the damper during the operation, which can cause efficiency reduction of cooling fins mounted onto the housing. In light of the numerical results, the suitable damper position has been determined for the highest heat transfer.
Development and Characterization of Sisal Fiber Reinforced Polypropylene Composite Materials
Authors: Gerezgiher Alula Gebresas , Bsrat Halefom Aregay , Simon Andrea , Szabó Tamás
Published: March 2019

In most of the developing countries, plastic polypropylene is not fully recycled and converted in-to use after it is once used. Sisal fiber is also widely available in different developing countries like Ethiopia. Adding this two materials and developing automotive interior part was taken as a primary motive for it reduces cost and is environmentally friendly. Thus, the main purpose of this research is to develop composite material from natural fibre (sisal fiber) reinforced with recycled plastic waste (polypropylene) for interior automobile accessories specifically for internal door trim panel application. This research examines effect of fiber length, fiber loading and chemical treatment of fiber on the physical and chemical properties of the sisal fiber reinforced polypropylene (SFRPP) composite material. The waste polypropylene and the treated and untreated sisal fiber with variable length and weight ratio (fiber/matrix ratio) were mixed. Flammability of sisal fiber reinforced Polypropylene (SFRPP) composites material was examined by a horizontal burning test according to ASTM D635 and chemical resistance of the sisal fibre reinforced PP composites was studied using ASTM D543 testing method. The result on the flammability test shows that treated fiber has lower burning rate than untreated fiber and decreases with increase in fiber length and fiber loading. The resistance of the composites to water has increased as the fiber length increases and decreased as the fiber loading increase. Generally, SFRPP composite is found to have better resistance to water than NaOH and H2SO4 and treating the fiber has brought considerable improvement on chemical resistance of the composite. Fiber loading and fiber length has positive and negative effect on the flammability of the SFRPP composite respectively.
Measuring the dynamic characteristics of electric motors
Authors: Szíki Gusztáv Áron , Szántó Attila , Sarvajcz Kornél
Published: March 2019

In our previous publications [1, 2], we described our vehicle dynamics simulation program which was developed in MATLAB environment. We also discussed its use for optimizing the technical parameters of electric driven vehicles. We detailed the model and simulation of the series wound DC motor which is part of the program. Besides, we described the experimental procedure by which we can determine the electromagnetic characteristics of the motor from the input parameters of the simulation program. In the present publication we deal with the determination of the dynamic characteristics of the motor (the moment of inertia of the rotor, bearing and brush resistance torques) experimentally. Knowing the above mentioned electromagnetic and dynamic characteristics, we can carry out the simulation of the motor and the results of the simulation can be compared to the results of the test measurements.
Development of a small-scale plastic recycling technology and a special filament product for 3D printing
Authors: Oussai Alaeddine , Bártfai Zoltán , Kátai László , Szalkai István
Published: March 2019

In our days, the fight against pollution has become a real challenge for the state. recycling is one of the solutions that is adopted in several nations to reduce the rate of plastic discarded in nature. The amount of plastic waste has been increasing for decades contributing to the environmental pollution that is one of the most serious problem of the mankind. according to the statistics not only the household plastic waste, but the industry discharge is increasing because the utilization of plastic as a raw material is more and more extending. plastic can be found in a lot of products, huge number of bottles, plastic bags, computers, auto parts are sold every day. The current applications for using recycled plastics in fabrication and design are fairly limited, on a small scale, plastics (such as abs, HDPe1, or Pe2t) are shredded and formed into pellets, and then either extruded into lament to be used in existing 3d printers, or injection molded into small parts and pieces of larger components. at a large scale, recycled HDpE is melted into sheets and either used directly as sheets in construction, or then heat formed from a sheet into components for construction. these methods of fabrication using recycled plastics are the norm because of their straightforward processes. nevertheless, each method leaves some complexity to be desired. This paper we study the types of plastics and diagnose the pollution caused by the latter. this allowed us to design and size a recycling station of plastic into filaments for three-dimensional printers. this station which will contribute to the fight against pollution. the station consists of two machines for grinding of the plastic and the other for the extrusion of the desired filaments. we were able to make a theoretical academic study on both machines and also we designed with solidworks 2015. The theoretical study is spread of the mechanical calculations necessary to the design and validation of the structure using the tools. as the prospect of this project, we want to complete the achievement of this station while completing the crusher and extruder mechanically. then switch to electric and electronic parts (introduction of engines, sensors and wiring...). In the case of waste plastics that are recyclable and reusable. the most widely used are polyethylene terephthalate (pet, used for synthetic fibers and water bottles), and second high-density polyethylene (hdpe, used for jugs, bottle caps, water pipes).
Improvement of High Strength Automotive Steels Wettability Properties Using CO2 Laser Surface Treatment
Authors: Tajti Ferenc , Berczeli Miklós , Weltsch Zoltán
Published: March 2019

As a result of stricter environmental and safety standards, vehicle manufacturers have to reduce the weight of the vehicles, because 10% weight loss cause 8-10% reduction of fuel consumption. To reduce car’s weight and increase safety, vehicle manufacturers use high-strength steels. Further weight reduction can be achieved by using corresponding bonding technology (soldering, sticking) and optimizing these technologies can increase the strength of the joints. According to literature research, the improvement of interface properties has a large effect on bonding technologies. In order to improve interface properties, we can use multiple surface treatments. In our research we investigate the effects of CO2 laser surface treatment on high strength steels, because CO2 lasers are often used in the vehicle industry. In order to detect the effect of surface treatment, we investigate the wettability of the treated and untreated steels. In our research we measure the surface tension of treated and untreated steels. Our main goal is to improve wettability properties thus the bonding technology. In our research we used DP 600 high strength steel sheet with the thickness of 1 mm. We cut the steel sheet to 25mm wide and 55mm long workpieces. Before the surface treatment, the workpieces had to be cleaned and degreased using methanol. We searched for parameters that do not cause any visible changes on the surfaces. Among the parameters of the treatment we were able to change the output power of the laser. We used contact angle measurement to examine the wettability.
A Slurry-Pot Abrasive Wear Test Device for Several Composite Materials
Authors: Muhandes Hasan , Kalácska Gábor
Published: March 2019

To choose the proper material for agricultural machinery we tested several materials with abrasive cloth on the pin-on-plate test device. After having the pre-results, we launched more complex abrasive testing (slurry-pot) simulating more realistic mode with soils to investigate the abrasive wear mechanism and resistance of the selected up-to-date polymeric structural materials. for this, we developed a modified slurry-pot test machine that ensures the comparability of the materials over a wide range of conditions. Through this device, several parameters could be controlled like speed, the soil particle’s hit angle on the tested surface.
Modeling the Thermal Behavior of Permanent Magnet Synchronous Motors
Authors: Lotfi Abdelhakim , Marcsa Dániel , Horváth Zoltán
Published: March 2019

The aim of this study is to present a thermal analysis of a permanent magnet synchronous machine based on finite element method. The developed model can be used to predict temperature distribution inside the studied motor during the rated operation. Electromagnetic computation is carried out with the aid of two 2D finite-element (FE) simulations on the cross-section of the PM motor. To analyse the process of heat transfer in an electrical machine, empirical correlations are used to describe the convective heat transfer from the different surfaces of the PM motor. The heat transfer coefficient is determined using dimensionless numbers and Nusselt number. After the loss calculation, the temperatures of the machine are calculated by using 3D finite element method. The results obtained by the model are compared with experimental results from testing the prototype electric motor.
Digital Twin and Shadow in Smart Pork Fetteners
Authors: Erdélyi Viktor , Jánosi László
Published: March 2019

This paper introduces our ongoing research in the field of smart livestock farming. The base idea in this research is to take some industry based concepts, and adapt them into agriculture. In Industry we live the  fourth industrial revolution, which is not a technical, but an organization revolution. So in this concept there are two key ideas, which are digital twin, and digital shadow. This article is about creating digital twin and digital shadow of a modern pig fattener. These models are based on the literature, and are identified on the data shared in these. However, these models can’t be used on real systems before identifying them on the actual circumstances. At this stage of research only digital twin of the product was created, and only some aspects of it. This however can simulate an average porkers feed consumption, weight growth and calculate the weight on certain stages of breeding. Further development is ongoing and our target is to make a fully functional model of a pig fattener.
Рост твердых растворов InAs-=SUB=-x-=/SUB=-Sb-=SUB=-1-x-=/SUB=- на отклоненных подложках GaAs(001) методом молекулярно-лучевой эпитаксии
Authors: Емельянов Е.А. , Васев А.В. , Семягин Б.Р. , Есин М.Ю. , Лошкарев И.Д. , Василенко А.П. , Путято М.А. , Петрушков М.О. , Преображенский В.В.
Published: March 2019

The influence of substrate misorientation degree on
the composition and morphology of layers during molecular-beam
epitaxy of InAsxSb1−x solid solutions on the GaAs surface was
studied. The GaAs wafers with orientation (001), which were
miscuted in the [110] direction by 0, 1, 2 and 5◦, were used
as substrates. The growth of heterostructures was performed for
temperatures of 310◦C and 380◦C (lower and upper boundaries
for the temperature range of structurally perfect InAsx Sb1−x films
formation, respectively). The influence of the arsenic molecular
form (As2 or As4) on the composition of layers was studied.
Studies of composition and structural properties were carried
out using high-resolution X-ray diffractometry (HRXRD) and
atomic force microscopy (AFM). It was established that in the
series of misorientation from 0 to 5◦ the arsenic fraction x increases
consecutively with the use of both flux of As2 and flux of
As4 molecules. When the flux of As2 molecules is used, the
fraction x increases insignificantly (in 1.05 times) with a rise of
misorientation degree, but when using As4 molecules, x increases
in 1.75 times. The increase of the growth temperature leads to the
rise of the arsenic fraction in the solid solution. The morphology
of the surface improves during increasing of misorientation degree
at a low growth temperature and degrades at high temperatures.
Мощные оптоэлектронные коммутаторы нано- и пикосекундного диапазона на основе высоковольтных кремниевых структур с p-n-переходами III. Эффекты саморазогрева
Authors: Кюрегян А.С.
Published: March 2019

AbstractThe self-heating effects of optoelectronic switches based on vertical high-voltage structures with p – n junctions (Vertical Photoactivated Semiconductor Switches, VPSS) operating in the high-frequency mode are theoretically studied for the first time. It is shown that the strong temperature dependence of the control-radiation absorbance κ( T ) is a major factor controlling the maximum switching frequency f _max and the corresponding maximum crystal temperature T _max, as well as the temperature T and current density j distributions over the device area. Two-dimensional analysis of the simplest electrothermal model of a VPSS embedded into a double coaxial forming line shows that an increase in the switching frequency f leads to current displacement to the device periphery where the temperature is minimum. However, the T and j distributions over the device area remain stable at   f < f _max and T < T _max. Certainly,   f _max and T _max depend on the control-radiation pulse energy, pulse switching power, and heat-removal conditions. For the VPSS based on indirect-gap semiconductors (Si, SiC), they vary within 20–120 kHz and 120–160°C which is quite sufficient for practical applications. However, VPSSs based on direct-gap semiconductors (GaAs, InP) are in fact inapplicable to operation in high-frequency modes due to the fact that the dependence κ( T ) is too sharp.
Влияние коагуляции капель воды на их распределение по размерам в рабочей части аэрохолодильной установки
Authors: Тимофеева М.В.
Published: March 2019

AbstractMathematical simulation of coagulation of droplets of finite number of size fractions of a polydisperse mixture, injected by a nozzle into the region of an air-cooler unit along air flux motion direction, was performed. Sets of differential equations describing dependences of droplet fraction concentrations, their densities, as well as masses of droplets in each fraction on time, were solved using the fourth-order Runge–Kutta method. Negligibility of the impact of heat-mass exchange between the substance of droplets and surrounding air on changing their sizes during motion from the nozzle to the operating part of the device is shown. Decomposition of droplets is not simulated, since the critical Weber number is not reached in the considered operating regime of the air-cooler. Results of simulation of droplet coagulation in turbulent air flux show that distributions of droplets by sizes near the surface of a spraying nozzle do not coincide, which proves the necessity of accounting this process in simulation of ice coating of aircrafts in ground conditions.
Оценка термодинамической эффективности работы твердотельных охладителей и генераторов на мультикалорическом эффекте
Authors: Старков А.С. , Пахомов О.В. , Родионов В.В. , Амиров А.А. , Старков И.А.
Published: March 2019

AbstractThe efficiency of using the multicaloric effect (μCE) in solid-state cooling systems is investigated and compared with single caloric effects. The proposed approach is illustrated by the example of the Brighton cycle for μCE and the magnetocaloric effect. Based on the conducted experiments for the two-layer composite Fe_48Rh_52–PbZr_0.53Ti_0.47O_3, the dependence of relative efficiency on temperature is constructed and the temperature range is estimated, where μCE has an advantage over the magnetocaloric effect. The comparison of the developed theory of the μCE with the obtained experimental data is performed.
Определение отношения Mn/Fe в железомарганцевых конкрециях с помощью безэталонной лазерно-искровой эмиссионной спектроскопии
Authors: Ахметжанов Т.Ф. , Лабутин Т.А. , Зайцев С.М. , Дроздова А.Н. , Попов А.М.
Published: March 2019

AbstractThe Mn/Fe ratio in ferromanganese nodules is determined by calibration-free laser-induced breakdown spectroscopy based on the use of only the plasma temperature and electron density and the intensities of manganese and iron analytical lines (Mn I at 447.28 and 447.93 nm and Fe I at 447.65 nm). The plasma temperature was determined by the two-line method (Mn I at 447.28 and 447.93 nm), while the plasma electron density was determined by the Stark broadening of the Mg I line at 517.26 nm. The study was performed using both standard samples (OOPE series) and samples of ferromanganese nodules sampled during expeditions to the Kara and Laptev Seas. The possibility of semiquantitative determination of the Mn/Fe ratio within the range from 0.2 to 4.2, which is enough for determining this ratio in most types of nodules of different geographical origins, is demonstrated. The calibration-free analysis data correlate with the results of inductively coupled plasma atomic emission analysis.