bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative technical and economic analysis of the Trombe wall use in the heat supply system at different climatic conditions
Authors: Kostikov S , Grinkrug M , Yiqiang J 
Published: September 2020

Abstract
This article is devoted to the problems of using any solar heating systems, the Trombe wall in particular, in modern heating systems and various climatic conditions. The main problem in solar heating systems is that the climatic conditions can be very different in one latitude, while the appropriateness of the Trombe wall using in heat supply systems will depend on the ratio between the incident solar energy and the room heat load. The main goal of this work is to determine the most effective climate divide for the Trombe wall using. This paper presents an algorithm for the technical and economic analysis of the Trombe wall effectiveness. The calculation results showed that the most appropriate Trombe wall use in the heat supply system is observed in the range of latitudes from 55° to 40° N. At the same time, the payback period of the Trombe wall is in the range from 3.5 to 10 years.
Liquid Sn-20Li alloy as a heat transfer fluid
Authors: Krasin V P 
Published: September 2020

Abstract
The purpose of present study was to obtain information on the solubility of components of structural materials in liquid Sn-20Li alloy in the temperature range of practical interest. To solve this problem, a thermodynamic simulation method was used, which included the following steps: (1) selection of models for the Gibbs energy functions; (2) selection and evaluation of input data; (3) optimization of model parameters; (4) calculations and comparisons. Using information on the excess Gibbs energies for the liquid phase in the form of Redlich-Kister polynomial expansions, for the corresponding binary systems, the temperature dependencies of solubility of nickel, iron, chromium, molybdenum and tungsten in the liquid Sn-20Li are calculated. The results of the calculations are in satisfactory agreement with the experimental data known from the literature.
Virtual thermal tests of heating devices
Authors: Pukhkal V 
Published: September 2020

Abstract
To determine the values of the nominal indicators of heating devices, thermal tests are carried out. Analysis of the literature data has shown that, despite the widespread use of mathematical modeling for the study of heat transfer processes in heating devices, there is no comparison of test data and modeling. The purpose of this study is to test a heating device in a chamber (an indoor convector with a natural impulse of air movement) and compare it with the results of modeling. To assess the possibility of using and accuracy of modeling tests of heating devices, the data of tests of the indoor convector with natural convection “Golfstream” KRK 20.11.150 (LLC “Izoterm”), performed by the Institute “HLK Stuttgart” (Germany), were accepted. Modeling of the test chamber and convector is based on the FloEFD software package of “Axis Engineering” company. During virtual thermal tests of the convector, a heat flow was obtained that differs from the data of the convector tests on the test stand by 4.9%. It is concluded that it is possible to conduct virtual tests to optimize the design of heating devices and obtain the thermal characteristics of heating devices under all operating conditions and modes.
Statistical testing of hypotheses about the form of the factor law of influence by the Kolmogorov criterion
Authors: Tumanov A , Sabanaev A , Solovyov A , Tumanov V 
Published: September 2020

Abstract
When affected by the impact of emergency sources on the same type of elementary objects, the depth of the introduction of shrapnel into the barrier changes randomly. It is necessary to determine the law of distribution of random depth of inserting fragments into the barrier. In the course of the work, hypotheses about three distribution laws were tested. Based on the results of experimental studies, it is proposed to assess the suitability of the law of distribution, the statistics of which, according to the Kolmogorov criterion, is intended to check the alignment of empirical distribution with this continuous theoretical distribution. With a small number of tests on the criterion Kolmogorov confirmed the consent of even clearly incompatible samples. However, with a large number of observations (more than 50) the Kolmogorov Criterion is able to detect any deviation from the hypothesis.
Geometric and mechanical parameters for the adjustment of the preload of differential bearings in gearboxes of automobile axles
Authors: Vasiliev A , Bulavin I , Samoilova A 
Published: September 2020

Abstract
This article discusses the construction of bearing units of different cars differentials and provides the analysis of technical requirements for the adjustment of the preload of bearings. There are four most commonly used methods for the adjustment of the preload. This paper defines a method for the adjustment of the preload based on deformation of bearing seats, which is the most acceptable in production and which is characterized by the least indirect adjustment and consequently the least number of failures. A formula is given for the calculation of the required preload force based on the failure in opening the joint in the unloaded bearing. A description of industrial equipment for the implementation of this method is presented.
Study of the influence of the brake shoe temperature and wheel tread on braking effectiveness
Authors: Ivanov P , Khudonogov A , Dulskiy E , Manuilov N , Khamnaeva A , Korsun A , Treskin S 
Published: September 2020

Abstract
This article considers the coefficient of friction between the brake shoe and the wheel of the railway rolling stock. It conducts a review of the works on the study of the interaction of the brake shoe and wheel, considers a method for obtaining the calculated value of the friction coefficient used in the Russian Federation and in many countries, and indicates a drawback of this method that leads to errors in the calculations. The paper specially focuses on the study of heating of brake shoes during braking as a factor in changing the coefficient of friction between the wheel and the brake shoe. The FEM model of heating the brake shoes during braking is constructed taking into account changes in the mass and shape of the brake shoes during wear. Brake shoe wear is considered as a factor in changing the effectiveness of train brakes.
The problem spreading acoustic waves in a porous environment with air bubbles on por walls
Authors: Sitdikova L F , Gimaltdinov I K 
Published: September 2020

Abstract
The propagation of acoustic waves in a porous medium with air bubbles on the pore walls is numerically studied. Based on the equations of mechanics of multiphase media, a dispersion relation is obtained that describes the dependence of the complex wave vector on frequency, on the basis of which the dependence of the phase velocity and attenuation coefficient on frequency for “fast” and “slow” waves is studied. The calculation results make it possible to evaluate the effect of gas bubbles on the propagation of sound waves in a porous medium with bubbles on the pore walls. The study was carried out with the financial support of the Russian Federal Property Fund in the framework of the scientific project No. 19-31-60015.
Biomechanics, physics and energy modelling of motion control
Authors: Pomerantsev A 
Published: September 2020

Abstract
Free throws in basketball were chosen to search for regularities of motion control. Ten female basketball students took part in the experiment, each of whom performed a series of throws up to 10 hits. Using the method of high-speed video shooting and numerical simulation, the analysis of kinematic characteristics of the throws, biomechanics, physics and energy modelling of motion control was performed. As a result of the study the regularity was revealed, consisting in the fact that during repeated throws the motion control is carried out by correcting ballistic parameters from the boundary of the effective hit zone to the central zone of the most reliable hit. Sportswomen with a high degree of accuracy determined the direction of correction, but they could hardly determine the quantitative value of the correction itself. By analyzing the parameters of each individual throw directly, the second general regularity of motion control was found. A throw as a movement regularity is divided into two parts: preparatory – when an athlete from any game situation strives to take a standard (maximally familiar and maximally stereotypical) position with minimal uncertainty; and the main one – when from a standard position, based on motor memory according to the principle of the “reflex ring”, targeted movement correction is carried out. The second part of the movement allows for the possibility of random errors and excessive corrections occurrence.
Analytical solution of the Navier-Stoks equations reduced to the third-order equation for the problem of fluid motion in a round pipe
Authors: Khudjaev M 
Published: September 2020

Abstract
The paper defines a rheological law that takes into account the molecular and molar transfer of fluid particles between the layers of the flow; the equation of fluid motion, taking into account two mechanisms of molecular and molar exchange of momentum in the flow; the form of the obtained new equations in the form of an equation of the boundary layer, neglecting the terms whose order is much lower than the order held in the equations; statement of the problem of stationary fluid flow in cylindrical coordinates with the corresponding boundary conditions using the transition to new dimensionless variables; a technique for solving the Navier-Stokes equation reduced to a third-order differential equation for studying the motion of a fluid in a round pipe; analytical solution of the formulated problem; the role of the newly introduced molar transfer coefficient in describing the flow pattern. An analytical solution of the problem of fluid motion in a cylindrical pipe is obtained, taking into account these two transfer mechanisms where third-order terms are formed in the Navier-Stokes equations. For small Reynolds numbers, the influence of the newly introduced term on the flow pattern is a shortening of the length of the initial segment of motion. A decrease in the value of the new number is associated with an increase in this region.
Improving the resistance of road pavements to rutting
Authors: Aleksandrov A , Dolgih G , Aleksandrova N 
Published: September 2020

Abstract
The aim of the article is to analyze the types of ruts formed on the surface of coatings, to study the causes of their appearance and develop construction of pavements with increased resistance to rutting. A technique is described for an experimental study of the distribution of tire passes over the width of a lane. During the experiment on existing roads, accounting points of the distribution of tire passes were organized. At each registration point, numbered strips are applied to the roadway, separating numbered sections 30 cm wide. Based on the results of an experimental study, empirical distributions of tire passes along the width of the roadway are established. The empirical data made it possible to establish discrete distributions of tire passes in width, with the help of which a correction factor was introduced into the calculation of the total number of repeated design loads. This coefficient allows calculating the number of passes in longitudinal sections located at different distances from you to the edge of the roadway or the axis of the road. As a result, central and edge parts that perceive the largest number of passages of the twin tires of the rear axles of the cars are highlighted on the tracks. To increase the resistance of pavements to rutting, constructions with unequal strength in width are proposed. The greatest strength and resistance to rutting belong to longitudinal sections on which the largest number of tires of the rear axles pass. In longitudinal sections between the ruts, the pavement is less strong. The increased strength of sections prone to rutting is achieved by creating hidden (secret) elements. Such elements are arranged in sump hole of either a subgrade or a base of granular material. Drawings of pavement construction are given.
Solving a dynamic routing problem using an optimization algorithm
Authors: Lebedeva O A , Poltavskaya J O , Gozbenko V , Mikhailov A 
Published: September 2020

Abstract
Optimizing the configuration of the freight transport network is a challenge. The search for the optimal route solution in a dynamic urban multimodal transport network is aimed at minimizing the cost based on accurate forecasting of traffic flows and cost estimation. The purpose of the study is to review a methodology that can be applied centrally, by an organization that develops solutions for routing shippers, minimizing the total cost, assuming that all shippers involved in transportation send their requirements to a single coordinating center. Evaluation of a multimodal cargo routing system with restrictions on the number of vehicles is based on a hierarchical approach. It consists of several stages: prognostic modeling of the state of the traffic load of the road network and cost estimation for optimization, which includes a methodology for finding the optimal load to accelerate the convergence of the algorithm.
Precise clock synchronization for radio frequency positioning system based on White Rabbit PTP
Authors: Fedotov A , Orlov I , Antonov A 
Published: September 2020

Abstract
Use case of the White Rabbit Precision Time Protocol (PTP) sub-nanosecond clock synchronization system in complex with Time-to-Digital Converter (TDC) is examined for precise time of RF signal arrival capture. Implemented WR PTP core port on target hardware platform is explained. TDC placement method for Intel Quartus Prime tool is also shown.
Energy-efficient Managing of Data Transmission in Socio-Cyberphysical System at Critical Facility
Authors: Ofitserov A , Budkov V , Letenkov M , Usina E 
Published: September 2020

Abstract
This paper describes information management exchange processes in data transmission network of a socio-cyberphysical system of a critical facility, ensuring secure data transmission. The lock-free routing approach, developed on the basis of this model, includes a number of methods, the implementation of which allows to meet reliability requirements as when designing of an energy-efficient data transmission network of a socio-cyberphysical system on a critical facility from scratch, as when modifying an already existing one. A composite efficiency measure gain is presented here, as well practical suggestions concerning practical application of the developed methods are given.
Breath testing for intra-abdominal infection: appendicitis, a preliminary study
Authors: Andrews B T , Das P , Denzer W , Ritchie G A , Peverall R , Hamade A M , Hancock G 
Published: September 2020

Abstract
In the current pilot study we aimed to determine whether breath analysis could be used to help recognise intra-abdominal infection, using acute appendicitis as an exemplar condition.
Our study included 53 patients (aged 18–88 years) divided into three groups: appendix group, 26 (13 male) patients suffering from acute appendicitis; control group 20 (seven male) patients undergoing elective abdominal surgery; normal group, seven patients who were clinically diagnosed with appendicitis, but whose appendix was normal on histological examination. Samples of breath were analysed using ion molecule reaction mass spectroscopy measuring the concentration of volatile compounds (VCs) with molecular masses 27–123. Intraperitoneal gas samples were collected from a subset of 23 patients (nine diagnosed with acute appendicitis).
Statistically significant differences in the concentration of VCs in breath were found between the three groups. Acetone, isopropanol, propanol, butyric acid, and further unassigned VCs with molecular mass/charge ratio (m/z) 56, 61 and 87 were all identified with significant endogenous contributions. Principle component analysis was able to separate the control and appendicitis groups for seven variables: m/z = 56, 58, 59, 60, 61, 87 and 88. Comparing breath and intraperitoneal samples showed significant relationships for acetone and the VC with m/z = 61.
Our data suggest that it may be possible to help diagnose acute appendicitis by breath analysis; however, factors such as length of starvation remain to be properly accounted for and the management or mitigation of background levels needs to be properly addressed, and larger studies relating breath VCs to the causative organisms may help to highlight the relative importance of individual VCs.
Water Quality Status of Pergau Reservoir Water Catchment and Lake, Jeli, Kelantan
Authors: Samsudin Mohamad Fikri , Mohd Amin Mohamad Faiz , Syed Omar Sharifah Aisyah , Yusoff Abdul Hafidz , Sulaiman Mohd Sofiyan 
Published: September 2020

Abstract
A study has been conducted in Pergau Reservoir water intake in Jeli Kelantan. Pergau reservoir is a man-made lake that uses to generate electricity for Kelantan State. Tenaga Nasional Berhad (TNB) was organized the Pergau Scientific Expedition 2019 on 28th October 2019 until 3rd November 2019 in order to check the current status of water catchment of Pergau lake as the intake for the reservoir. In this study, 12 sampling sites was identified by TNB which seven in water catchment area and five stations in lake. During sampling works, water sample were collected for ex-situ analysis and for in-situ analysis, water quality reading was taken using YSI multiparameter. During this study, greater reading was recorded in lake compared to river due to altitude and canopy cover that affect water quality. Greater reading on water turbidity and temperature in lake because affect by natural process and human activity while in river, canopy layer reduces the sunlight penetration. Based on Malaysia Department of Environment, water quality index for both river and lake were identified at 93.3 and 95.1 respectively which classified as clean. Based on this study, clean water quality index will ensure the water safe to be used and environment was healthy.
A Development of a ‘ArcSWAT’ Surface Runoff Model for Estimating Urban Precipitation Recharge
Authors: Jamil Rohazaini Muhammad 
Published: September 2020

Abstract
Groundwater recharge estimation is a fundamental part of groundwater resources management and may need to be estimated at a variety of spatial and temporal scales. Recharge is variable in time, responding to changes in land use and subsurface infrastructure as well as to climatic changes. Howevera, estimating recharge in urban environments is more complex than rural environments as it has many sources and pathways for recharge. Buildings, roads, land cover permeability, and other surface infrastructure combine with man-made drainage networks to influence recharge. Thus, this study is trying out an existing GIS-based system (ArcSWAT) to model and estimate urban recharge. The unconfined Triassic sandstone aquifer that underlies part of the city of Birmingham, United Kingdom (UK) was used as the study area for this project (occupies around 94.2km2 area). The results from this study show that SWAT model correlates better with 4RH (RMSE=17.78) as compared to UGif (RMSE=38.89) and 4ReH (RMSE=28.08). This is due to the reason that mains leakage factor has been included in 4RH and SWAT model. In summary, SWAT model produced a satisfactory result of urban precipitation recharge to the previous study that includes mains leakage factor during the modelling process.
Statistical and Spatial Analyses of the Kelantan Big Yellow Flood 2014
Authors: Achmad Bahar Arham Muchtar , Muhammad Marinah , Ali Khan Mohammad Muqtada , Naim Jemali Noor Janatun 
Published: September 2020

Abstract
Flooding is a yearly phenomenon which is mostly reflected in the Kelantan River basin during the northeast monsoon season due to the heavy rainfall. The December 2014 flood in Kelantan known as ‘Kelantan big yellow flood’ was unprecedented and the largest recorded flooding event in the century. Flood mitigation, especially in massive floods, should focus on minimizing the risk of severe flooding in one area. A reliable flood extent map is essential to plan proper flood mitigation measures by authorities prior to the extreme flood event (say 1 in 1000 years event). This study is an attempt to resolve the issue of severe flooding in a given area by preparing a map of zones prone to flooding. This was achieved mainly by site visits to the flood-prone area and gathering primary data from face to face interview with local people who were the victims of this flooding. This primary data is also crucial in determining flood vulnerability with respect to economic and social impacts. The integration of primary data with secondary data from several related agencies has resulted in preparing a reliable flood extent map which is slightly different from other such maps developed by Government, NGOs and active researchers in this field. The empirical findings using frequency analysis also helped in preparing a flood vulnerability index based on primary data gathered from the local people who were the flood victims.
Properties and Occurrences of Rock Coatings in Jeli, Kelantan As A Record of Environmental Processes
Authors: Abdul Rahim Nurul Aina Halimah , Ismail Roniza 
Published: September 2020

AbstractRock coatings can be defined as a product material deposition from surroundings. It is resulted from the wide variety of reactions which occur at the interface between the lithosphere and the biosphere. The coatings are biochemically and mineralogically complex and have the potential to record changes in their immediate environment. The changing of the coating gives information about the factors involved during the process which include dissolution and chemical reaction. The range of their activities and their proper significance in the environment as well as their relationship with the microorganisms that inhibit rocks and minerals provide a lot of information of the process involved. Types of coatings that have been identified on the outcrops around Kampung Kalai, Jeli are case hardening, iron film, dust film, rock varnish and lithobiontic coatings. The environmental exposures and inputs to the coatings, determines the coating mineralogy that formed on the parent rock. Scanning Electron Microscope (SEM) was used to analyse the microscopic properties of the coating samples. The presence of iron oxides have been found on the brick orange coating which potentially occurred from chemical weathering such as oxidation and the leaching of iron-bearing minerals. Besides that, geochemical analyses using X-Ray Fluorescence (XRF) on selected samples have shown limited information about the changing elemental composition. Iron, aluminium and silica are the major elements composition in the rock coatings reflecting the similar elemental composition of the existing parent rock.