bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination wear intensity of electrical brushes in DC machines considering impact of collector’s surface
Authors: Kharlamov V V , Popov D I , Baysadykov M F 
Published: September 2019

Abstract
One of the most loaded units affecting the reliability of DC machines is the collector-brush unit. There is a continuous process of mechanical, electrical and chemical interaction of the electric brushes with the collector during operation of the DC motor, which increases the wear of the electric brushes. In a result of the analysis of the works, devoted to the study of the operation of the collector-brush unit’s elements, the authors proposed a mathematical model for determining the intensity of wear of electric brushes, which allows taking into account the effect of the collector profile on the electric brushes wear intensity. The basic data and dependencies for modelling the movement of the electric brush on the collector surface, which based on the design scheme, are presented. A distinctive feature of the developed scheme is that the elastic force at the contact of the brush with the surface of the collector is determined from the side of each collector plate. For the above scheme, a system of differential equations is compiled, allowing simulating the movement of the brush in the radial and tangential direction during its interaction with the surface of the collector. The resulting mathematical model allows us to determine the trajectory of the brush and the oscillations of the elastic force that occurs at the point of contact of the brush with the collector, with different parameters of the collector-brush unit’s elements and modes of operation of the machine, causing a certain frequency of rotation of the armature. Taking into account the above mathematical model, a software product has been developed for calculating the wear rate of DC motor electric brushes during its operation. The practical value of the work is that the use of the developed software allows you to find more optimal operating parameters for the collector-brush unit of DC motor with a minimum of time.
Probabilistic forecasting of sudden power supply interruptions of electromechanical and heat-power equipment of regionally isolated electrotechnical complex
Authors: Kovalev V Z , Vyazigin V L , Arhipova O V , Yesin S S 
Published: September 2019

Abstract
There is considered probabilistic forecasting of the most important characteristics of sudden power supply interruptions — damage and downtime of electromechanical and heat-and-power equipment — for process plants typical for installations of a regionally isolated electrotechnical complex. These specifications are considered as random functions of the power supply interruptions duration. A feature of the specifications considered is the presence of finite jumps when the power supply exceeds the critical values. Generalized theoretical equations are obtained for continuous functions of mathematical expectation and variance of process downtime and damage when there is any number of finite jumps of certain implementations and there is consideration of the discontinuity points as random variables with different distribution laws. The obtained specifications are used to optimize the cost of creating power supply systems considering their reliability.
Multicomponent Biofuels for Agricultural Diesel Machines
Authors: Markov V A , Kamaltdinov V G , Zykov S A , Savastenko A A 
Published: September 2019

Abstract
Biofuels derived from vegetable oils are increasingly used in diesel engines. The article analyzes the physicochemical properties of petroleum diesel fuel and biofuels of various compositions. A technique has been developed to optimize the composition of multicomponent composite biofuels for diesel engines of agricultural machinery. The optimal composition of a mixture of petroleum diesel fuel, rapeseed oil and rapeseed oil methyl ester has been determined, providing the best combination of fuel efficiency and exhaust emissions. The optimization calculations made it possible to select the composition of a multicomponent mixed biofuel for the D-245.12S engine installed on domestic agricultural machines.
Analysis of Temperature Conditions Influence on Cables Insulation Operation Life
Authors: Pugach V N , Polyakov D A , Nikitin K I , Zakharov I L , Petukhova N N 
Published: September 2019

Abstract
Electrical equipment fault current interruptions reduce is one of the most important problems of electrical power engineering and diagnostics. Power cables operation life is one of the parameters mostly affecting fault current interruptions on cables. The paper describes the research on thermal degradation of low voltage cables insulating materials and its influence on insulation operation life. The known mathematical models of the insulation aging depending on its temperature are considered. Low voltage cables have an insignificant electrical aging influence, so it is assumed that such cables aging mostly caused by their thermal operating conditions. Experimental research of cables insulation temperature monitoring is performed. Seven weeks of the experiment showed a temperature change between 17˚C and 27˚C. The mean temperature was 21.9˚C. Assuming that cable has normal operation life with an average temperature of 20˚C and accounting thermal conditions cable insulation operation life is reduced for about 20%. Such operation life reduce is significant and shows a considerable influence of insulating material thermal deterioration.
Mathematical modeling of the magnetic field of a low-speed synchronous generator with permanent magnets
Authors: Tatevosyan A A 
Published: September 2019

Abstract
Increased scientific and practical interest in the development, design, research and implementation of low-speed synchronous generators with permanent magnets (SGPM) is caused by the need to completely equip various sectors of the economy with efficient renewable energy sources based on the principles of wind, hydro and pneumatic power. The impetus for the creative thinking of Russian and foreign science to create and introduce into production and operation new types of designs of magnetoelectric machines with excitation from permanent magnets was the emergence in the consumer market a wide range of available for use high-coercive permanent magnets based on rare earth elements of the alloy neodymium-iron-boron (NdFeB). In this paper we propose a design of low-speed synchronous generator with permanent magnets, taking into account the full list of requirements for renewable energy sources, accumulated in the practical experience of developing such electromechanical converters. The article presents the results of mathematical modeling of the magnetic field of low-speed synchronous generator using the package Ansoft Maxwell 16.0.
Experimental method for identifying high-coercive permanent magnets
Authors: Tatevosyan A S , Tatevosyan A A , Pedder V V , Zaharova N V 
Published: September 2019

Abstract
A bench was developed and a method for identifiying a pilot batch of high-coercive permanent magnets (HcPM) made of the same brand of neodymium-iron-boron alloy (NdFeB) was proposed. The tested samples from the trial amount of HcPM have the shape of a disk, a rectangular prism and an axial direction of magnetization. The criterion for the identification of the HcPM in each trial amount is their identical volume magnetization, which is taken into account by the standard deviation of the constructed experimental curves of the interaction electromagnetic force for each test sample of a permanent magnet from the trial amount with a magnetic reflector when the distance between them changes. As a magnetic reflector, a more powerful permanent magnet with a disk shape and a height exceeding the height of the permanent magnet test sample is used. Neglecting the procedure of identification of the HcPM from the trial amount leads to disruption of the electromagnetic systems incorporating them, for example, during the development of synchronous electric machines inductors based on permanent magnets, shaft beating, increased vibration of the operating elements, an increase in radial and axial load on the bearings, reduced service life and failure of electric machines during operation are observed.
Reconstruction of Terrain based on corrected Digital Elevation Models
Authors: Korotin A S , Popov E V 
Published: September 2019

Abstract
The paper describes the method of reducing the errors, primarily caused by vegetation, in open digital models like Aster and SRTM. These models do not usually meet the requirements of hydrological correctness due to the errors of different origin. The main errors of DEM are the distortion of the tilt angles and the absolute altitude component in the areas occupied by forest vegetation. We propose the method for eliminating vegetation cover by a local interpolation function and Lagrange polynomial interpolation. The paper also considers the comparison of the proposed method with other methods such as Triangulation Irregular Network (TIN), Inverse Distance Weighting (IDW), Natural Neighbor, Kriging, Radial Basis Functions.
Method of determining minimum area of residential development at different angles of rotation of buildings with allowance for insulation time length
Authors: Pritykin F N , Kurysheva E A 
Published: September 2019

Abstract
The paper proposes an analytical method for constructing the shadows of buildings and structures with the aim of using them in residential development planning. This method based on generalized coordinates and small movement synthesis of residential facilities allows finding the minimum construction area that meets the requirements of insulation regime. With this method the position of shadows relative to buildings is investigated at all iterations.
Modelling for the integer optimization of the production resources of the organization in the conditions of warranty support of goods
Authors: Ivanov V N 
Published: September 2019

Abstract
The article describes the economic and mathematical model to optimize the distribution of production resources of the organization in conditions of warranty support of goods. The model allows the integer assignment of such resources as, for example, equipment. The mathematical apparatus allows in a single system to consider the production of all goods from the nomenclature of the organization for each technological operation for each year of the project together with the warranty support of the goods. The system of limitations of the model, in addition to taking into account all items of possible costs, assumes the possibility of taking into account the impact of additional efforts aimed at ensuring quality in production on the subsequent volumes of work associated with the warranty.
Assortment analysis of shutter valves for spark ignition engines timing systems
Authors: Matla J 
Published: September 2019

Abstract
Continually tightened emission restrictions together with limited crude oil resources are factors driving more efficient fuel management strategies implementation. Such operations results in increase of internal combustion engine efficiency due to change in geometry and materials of existing systems as well as introducing new solutions. Over the years many approaches were taken. One of them was timing valve geometry optimization, which in case of conventional poppet valves is burden with number of restrictions. At this place some nonconventional designs might be introduced and one of them is so called shutter valve. Construction of shutter valve finds its roots in photographic industry where it is commonly used for exposition of photosensitive material for exactly determined period, enforcing very fast operation of mechanism similar like in case of valve train, which makes it suitable to adapt in engine timing system.
Study on the classification of actions aimed to reduce the fuel consumption of road vehicles in service
Authors: Luca L , Pasare M M , Dimitrov R , Luca T O 
Published: September 2019

Abstract
This paper addresses the major global problem of reducing fuel consumption in the transport sector. The authors present the results of a study on the use of a quality management tool - tree diagram. The actions aimed at reducing the fuel consumption of the road vehicles in operation have been identified and classified. A three-level tree diagram was developed to answer the question: How can fuel consumption be reduced? The chart provides a complete and suggestive picture of the actions to be taken to solve the proposed problem. The actions have been grouped into three corresponding categories for three specific objectives: the acquisition of a vehicle suitable for the needs; proper use of the vehicle (eco-driving); proper maintenance. The authors of the paper believe that the tree diagram obtained is a good tool for informing and raising the driver’s awareness of his role in reducing fuel consumption.
Study of the potential for reducing CO2 emissions from road transport in Bulgaria
Authors: Hristov R , Stefanov S 
Published: September 2019

Abstract
Environmental issues take an extremely important place in the life of modern society and the measures which individual states and organisations take to reduce the harmful effect of transport are essential. The report examines the legal framework and the actions taken by one of the European Union states - Bulgaria. As regards CO2 emissions, comparative results from a test of internal combustion engine fuelled with Petrol, LPG and CNG are shown. A survey was conducted to obtain the opinion of vehicle drivers on environmental issues and on introduction of cleaner vehicles - hybrid and electric vehicles. The results show that the reason for small electric vehicle sales is the lack of recharging points and the high price. The production, life and recycling of batteries are the other major issues noted in the survey. At present, the predominant production of electricity from thermal power stations using coals as a fuel does not give an advantage to electric transport, except to improve ecology in urban environment.
General Motors 6T automatic gearboxes - problems and methods for their removal
Authors: Stefanov S , Hristov R 
Published: September 2019

Abstract
Nowadays, with increased environmental requirements to improve fuel economy, it is important to work with both the ICE and the other elements of propulsion. This report describes how to operate automatic gearboxes and specially General Motors 6T. They are very widespread throughout the world and are used by many automotive manufacturers. The deficiencies encountered during the operation and the reasons for this are discussed. There was considered the opportunities for diagnosis, emerging operational problems and the options for their removal. It is suggested to replace parts exchange details of the construction in order to improve performance and reliability. The solenoids that control the switching are ON / OFF type or pressure regulators (with a progressive or regressive characteristic). A stand test of solenoids - pressure regulators has been done under cold and warm conditions. The test results are shown in tabular and graphical form. Using this method reduces the repair time of an automatic gearbox.
Analysis of the Capabilities of Pistons Design using SOLIDWORKS models
Authors: Petkov Delyan 
Published: September 2019

Abstract
The difficulty in designing internal combustion piston is determined by complex operating conditions. Piston is the busiest engine part. Combined mechanical and thermal loads work on it. Profiling the piston in two mutually perpendicular planes is a major part of its design. The shape of the piston in a cold state is quite different from the cylindrical one. The aim is, despite the varying amount of material in the various zones, when the working temperature reaches the piston to take cylindrical form, thus providing minimal clearance to the engine cylinder. Because it is a moving part, the parameters at work are hard to determine. There are studies of the piston temperature state, some of which are described and analysed.
Consequentialism in infinite worlds
Authors: Jonsson Adam , Peterson Martin 
Published: September 2019

Abstract
We show that in infinite worlds the following three conditions are incompatible: (1) The spatiotemporal ordering of individuals is morally irrelevant. (2) All else being equal, the act of bringing about a good outcome with a high probability is better than the act of bringing about the same outcome with a low probability. (3) One act is better than another only if there is a nonzero probability that it brings about a better outcome. The impossibility of combining these conditions shows that it is more costly to endorse (1) than has been previously acknowledged.
Maltreatment and Delinquency: Examining the Contexts of Offending Amongst Child Protection-Involved Children
Authors: Baidawi Susan , Sheehan Rosemary 
Published: September 2019

Abstract
Child protection-involved children experience disproportionately high criminal justice system contact, yet little is known about the circumstances in which such children offend. This study sought to identify the contexts in which this group of children offend and factors associated with children being charged in each context. A mixed-methods analysis of Children’s Court case files was conducted utilising a cross-sectional sample of 300 children who came before three Children’s Criminal Courts in Victoria, Australia, and who also had statutory Child Protection involvement. Three key contexts of offending were identified: adolescent family violence (AFV), residential care-based offending and group-based offending. A total of 33 per cent of children had engaged in AFV (23 per cent had AFV-related charges), 36 per cent of children ever placed in residential care acquired charges relating to their behaviour in these settings, while 44 per cent of children had engaged in group-based offending. More than one-third of children (38 per cent) also had criminal charges stemming from justice system interactions (e.g. resisting arrest). Children’s cumulative neurodevelopmental, mental health and substance abuse challenges correlated with offending in each context. Strategies to reduce youth justice contact amongst child protection-involved children should consider systems responses to AFV and behavioural challenges in residential care.
Development of New Antimicrobials for Urogenital Gonorrhea Therapy: Clinical Trial Design Considerations
Authors: Hook Edward W , Newman Lori , Drusano George , Evans Scott , Handsfield H Hunter , Jerse Ann E , Kong Fabian Y S , Lee Jeannette Y , Taylor Stephanie N , Deal Carolyn 
Published: September 2019

Abstract
Gonorrhea remains a major public health challenge, and current recommendations for gonorrhea treatment are threatened by evolving antimicrobial resistance and a diminished pipeline for new antibiotics. Evaluations of potential new treatments for gonorrhea currently make limited use of new understanding of the pharmacokinetic and pharmacodynamic contributors to effective therapy, the prevention of antimicrobial resistance, and newer designs for clinical trials. They are hampered by the requirement to utilize combination ceftriaxone/azithromycin therapy as the comparator regimen in noninferiority trials designed to seek an indication for gonorrhea therapy. Evolving gonococcal epidemiology and clinical trial design constraints hinder the enrollment of those populations at the greatest risk for gonorrhea (adolescents, women, and persons infected with antibiotic-resistant Neisseria gonorrhoeae). This article summarizes a recent meeting on the evaluation process for antimicrobials for urogenital gonorrhea treatment and encourages the consideration of new designs for the evaluation of gonorrhea therapy.
Frequent drinking is a more important risk factor for new-onset atrial fibrillation than binge drinking: a nationwide population-based study
Authors: Kim Yun Gi , Han Kyung-Do , Choi Jong-Il , Boo Ki Yung , Kim Do Young , Lee Kwang-No , Shim Jaemin , Kim Jin Seok , Kim Young-Hoon 
Published: September 2019

Abstract

Aims
Heavy consumption of alcohol is a known risk factor for new-onset atrial fibrillation (AF). We aimed to evaluate the relative importance of frequent drinking vs. binge drinking.

Methods and results
A total of 9 776 956 patients without AF who participated in a national health check-up programme were included in the analysis. The influence of drinking frequency (day per week), alcohol consumption per drinking session (grams per session), and alcohol consumption per week were studied. Compared with patients who drink twice per week (reference group), patients who drink once per week showed the lowest risk [hazard ratio (HR) 0.933, 95% confidence interval (CI) 0.916–0.950] and those who drink everyday had the highest risk for new-onset AF (HR 1.412, 95% CI 1.373–1.453), respectively. However, the amount of alcohol intake per drinking session did not present any clear association with new-onset AF. Regardless of whether weekly alcohol intake exceeded 210 g, the frequency of drinking was significantly associated with the risk of new-onset AF. In contrast, when patients were stratified by weekly alcohol intake (210 g per week), those who drink large amounts of alcohol per drinking session showed a lower risk of new-onset AF.

Conclusion
Frequent drinking and amount of alcohol consumption per week were significant risk factors for new-onset AF, whereas the amount of alcohol consumed per each drinking session was not an independent risk factor. Avoiding the habit of consuming a low but frequent amount of alcohol might therefore be important to prevent AF.
Health literacy and hypertension outcomes in a multi-ethnic population: the HELIUS study
Authors: Miranda R , Meeks K A C , Snijder M B , van den Born B J , Fransen M P , Peters R J , Stronks K , Agyemang C 
Published: September 2019

Abstract

Background
Hypertension disproportionately affects ethnic minority groups. Although health literacy may play role in these ethnic inequalities, little is known about the extent to which health literacy affects hypertension prevalence, awareness, treatment and control in different ethnic groups. Therefore, we assessed these associations in a multi-ethnic population.

Methods
Baseline data from the HELIUS study were used including participants of Dutch (n = 1948), South-Asian Surinamese (n = 2054) and African Surinamese (n = 1932) origin aged 18–70 years, who lived in Amsterdam, the Netherlands, were fluent in Dutch and underwent health literacy assessment through the Rapid Estimate of Adult Literacy in Medicine–Dutch (REALM-D). The REALM-D was categorized either as low (&lt;60 sumscore) or adequate (≥60 sumscore) health literacy. Participants completed questionnaires and underwent physical examination.

Results
After adjusting for confounding variables, Dutch [odds ratio (OR) 2.02; 95% confidence interval (CI), 1.11–3.64] and African Surinamese (OR 1.36; 1.03–1.79) with low health literacy were more likely than those with adequate health literacy to have hypertension, whereas in South-Asian Surinamese this association was not significant. No significant associations were found between health literacy and hypertension awareness, treatment and control in any of the ethnic groups.

Conclusion
Findings indicate that health literacy is associated with hypertension prevalence in selected ethnic groups, but not with hypertension awareness, treatment and control. Targeting health literacy might be an entry point for tackling ethnic inequalities in hypertension prevalence. To substantially reduce these inequalities, further research is needed to explore other factors and pathways through which health literacy may impact hypertension outcomes in different ethnic groups.