bluuebunny/crossref_metadata_2025 huggingface dataset:
Estimation of the electric force effect on dispersed additives in the heterogenous combustion flame plasma in the electrostatic field presence
Authors: Zyryanov I A , Budin A G , Pozolotin A P , Kargapoltsev V V
Published: October 2019

In the work, the influence of the electric force from the external electric field on the charged dispersed particles in the flame was evaluated. It is assumed that changes in the effect of the field on the combustion rate in the presence of dispersed additives in the gas phase take place due to the heat flux into the burning polymer condensed phase changes. However, as it turned out, the flame front moving towards the fuel under the action of field forces does not allow to fully explain the combustion rate increase.
Dual-program impulse modulation of plasmatron power in processes of plasma spraying
Authors: Kadyrmetov A. M. , Sharifullin S.N. , Buhtoyarov V.N. , Snyatkov Ye.V. , Pustovalov A.S.
Published: October 2019

On the basis of analysis of plasma coating processes the influence of electrical parameters modulation of the remote arc on the temperature field in the “coating-base” system in the local scale, proportional to the diameter of the arc binding spot to the surface, and in the macro scale of sprayed surface is valued. Dual-program impulse modulation of plasmatron power, providing uniform distribution of the coating connection strength with the substrate layer based on uniform distribution of surface thermal activation and local zones of coating penetration on the sprayed surface is offered.
Propagation of compression wave in the liquid at collapse of a spherical gas cavity under non-isothermal conditions
Authors: Morenko I V
Published: October 2019

The problem of the collapse of a spherical gas cavity in a fluid under non-isothermal conditions is considered. Numerical simulation of the motion of a two-phase medium is based on the volume of fluid method (VOF). The numerical results of fluid pressure history at control points located at different distances from the center of the cavity during the process are obtained.
Classification of time series using the Hurst exponent
Authors: Nazarychev S A , Zagretdinov A R , Ziganshin Sh G , Vankov Yu V
Published: October 2019

The Hurst exponent allows to classify time series according to the level of their stochasticity. To calculate it, the rescaled range analysis (R/S analysis) is applied. The article presents the R/S analysis algorithm. A program has been developed in the LabView programming environment. Performance check program carried out on the model signals.
The application of pulsed discharge for sterilization of freeze-dried product
Authors: Ya Asadullin T , Galeev I G , Sofronitskiy A O
Published: October 2019

Freeze-dried products are food products prepared by using the freeze-drying method. Freeze-drying is a technology of removing water from fresh products by vacuum method. In the production of food products it allows almost completely preserve their nutrients, vitamins, minerals, even the original form, natural smell, taste, color under a various of storage conditions. During the drying process, the residual water content reaches a value of about 10%. For safe and secure preservation of dehydrated products, it is necessary to sterilize them and the package proper during the packaging process. For the purpose, it is convenient to use a pulsed gas discharge, which will be ignited inside the package during the vacuuming process. The pulsed nature of the discharge provides high efficiency of creating sterilizing agents in the form of ozone and ultraviolet radiation at low heat deposition. Air exhaust removes gaseous reaction products caused by the discharge. The porosity and dielectric properties of freeze-dried products provide high quality sterilization.
Heat and mass transfer in different multiphase environments
Authors: Sultanov V A , Karataev O R
Published: October 2019

Annotation text: the paper presents a method for studying the process of heat and mass transfer, dividing it into three elementary types: thermal conductivity, convection and thermal radiation, as well as examples of these types occurring in reality in multiphase media.
Surface activation of polyamide fibers by radio-frequency capacitive plasma for application of functional coatings
Authors: Timoshina Y A , Voznesensky E F , Tskhay E S , Sysoev V A , Krasina I V , Kulevtsov G N
Published: October 2019

The results of experimental researches on the modification of polyamide fibrous materials for technical purposes by low-pressure radio-frequency capacitive discharge plasma are presented. The effect of plasma modification on the wettability of polyamide fibers and their adhesive properties was studied.
About the role of tribroplasma in the process of water extract from the exhaust tract of the engine of internal combustion when treating them by tribosettes
Authors: Sharifullin S N , Dunaev A V
Published: October 2019

The abundant water release during the processing of ICE by tribosystems was observed by many practitioners of PBC repair. The hypotheses of its causes are ambiguous. Some say that the source of water is motor oil or decomposition of pollution of ICE. Others believe that the source of water is humid air. Still others emphasize that water emission is concealed in the exhaust tract of the engine with neutralizers and turbochargers. There is a saying that this is just a condensate discharge from the engine exhaust tract. However, abundant water release occurs only with the introduction of the PBC drug in the friction unit. It is believed that the main reason is associated with the presence of triboplasma, which is formed when the contact spots of the friction site mating surfaces come off. In the area of triboplasm, the tribopreparation undergoes a plasma-chemical reaction, is split with the release of high thermal energy, which creates other conditions for moist air, fuel, engine oil and ICE pollution. All interpretations of the causes of water emission may be erroneous, since it contradicts the prevailing ideas about the work of the internal combustion engine.
Research of mechanical characteristics thin coating
Authors: Yakupov S N , Yakupov N M
Published: October 2019

To solve many technical and economic problems, thin-walled coated structures are created. Coatings are usually formed directly on curved surfaces of structural elements and have a complex structure and complex surface relief. At the same time, some coatings are almost impossible to dismember from the substrate.

An approach to study the stiffness properties of non-separable coatings on a thin-walled substrate of complex shape, based on the fact that the tensile stiffness of the coating is equal to the difference in the stiffness of the substrate with the coating minus the stiffness of the thin-walled substrate. The experimental-theoretical method is used to estimate the stiffness. A formula for estimating the Poisson’s ratio for the initially flat version of the substrate in the elastic formulation for cases of small deflection is obtained. An example of an assessment of the hardness of the coating with the flat substrate. It was found that the stiffness of the coating is 53.3 % of the substrate stiffness.

The approach is effective in the study of the mechanical properties of coatings, especially when the stiffness of the coating and the substrate of the same order.
Application of the New Generation Large Capacity Synchronous Condenser in HVDC System
Authors: Guo Zhilin , Hao Liangliang , Wu Junyong
Published: October 2019

The AC dynamic reactive power compensation in high voltage direct current (HVDC) still remains an unsolved problem. Owing to its flexible and rapid reactive power output, synchronous condenser (SC) has a broad application prospect on sending and receiving ends of HVDC transmission system. Firstly, the system structure of a new large capacity SC is introduced. Secondly, reactive power dynamic characteristics of SC in sub-transient and transient are studied theoretically. Then its supporting effect on low bus voltage is analyzed and verified. On this basis, the reactive power application requirements of SC in DC system are studied. An actual transmission system model is established by PSCAD/EMTDC. The simulation verifies the suppression effect of SC on commutation failure and bus transient overvoltage, which provides a theoretical basis for the application of SC in HVDC system.
Smoothing Control Strategy of Wind Power Based on Adaptive Adjustment of Fluctuation Coefficient
Authors: Yi Luo , Kunlin Su , Jiye Yin
Published: October 2019

Due to the strong randomness and fluctuation of wind power, a direct access to the power grid will be an adverse effect on the quality of the power. The energy storage system can not only reduce the phenomenon of abandoned wind power, but also improve the quality of the power grid. In order to smooth the fluctuation of wind power, we propose a smooth control strategy of wind power based on adaptive adjustment of fluctuation coefficient is optimized. The optimal model is designed which is based on minimize the energy storage capacity. The method of sliding window and particle swarm optimization (PSO) is used to solve the problem The wind power grid-connected power value is obtained.
Digital Twin and AAS in the Industry 4.0 Framework
Authors: Bradac Z , Marcon P , Zezulka F , Arm J , Benesl T
Published: October 2019

The paper goes out from the state of the art in the area of Industry 4.0 initiative of the most developed countries. There are also discussed reasons of Industry 4.0 development and implementation into existing still developed technologies. According to the last development, the term digital twin became a very often-used word. Authors explain differences in the content of the digital twin and recommend to use for the Industry 4.0 area the more appropriate and precise specified term – the Asset Administration Shell (AAS). Next parts of the contribution therefore deal with the Asset Administration Shell (AAS) in details to enable engineers, technicians and informatics from the praxis much more simple introduction in the Industry 4.0 problems and their solution. There is introduced and explained the structure of the AAS, the model and sub-models architecture, parameters and features in the contribution.
A Stable Control Algorithm for Multi Robot Formation
Authors: Shakev Nikola , Topalov Andon V , Ahmed Sevil A , Popov Vasil L
Published: October 2019

This paper presents the developed trajectory tracking controller for a formation of nonholonomic robots, which combines features from the leader-follower and virtual-structure approaches. The implemented decentralized control strategy allows the robots to be relatively independent and to switch easily between the executed individual tasks and the collective tasks. Convergence is thoroughly analyzed and guarantied using the Lyapunov approach.
Combination of Virtual Private Network and Wireless Sensor Network: Protection Against The Interference Problem of IOT
Authors: Majumdar Pramathesh , Jain Rachna , Pandey Ayushi , Majumdar Rana , Khatri Sunil Kumar
Published: October 2019

As the era of the Internet of Things (IoT) is emerging rapidly, the interference problem is also increasing at the same pace. In IoT based connections, as we know that devices share a common communication channel to interact with each other, the interference problem arises as all the devices are connected. Once an attacker gains access to any of the devices in an IoT enabled network, the whole IoT network becomes susceptible to breach. The biggest example of it is the IoT enabled CCTV hacking. In this work, we are proposing the usage of Virtual Private Network (VPN) and Wireless Sensor Network (WSN) to create a virtual environment and to protect each device from IP address breach that is connected to an IoT network. Using VPN, each IoT device will gain their own virtual environment which will enable it for using a dynamic IP address to connect to another IoT device’s virtual environment. Using WSN, the virtual environments will be able to identify any signal interference that can cause any security breach.
Deposition and tribomechanical study of nanolaminate Ti/TiN/AlTiSiN/(AlTiSiN/TiAlSiN)n/AlTiSiN hard coating
Authors: Rupetsov Velko , Kolaklieva Lilyana , Chitanov Vassiliy , Angelov Milko , Raychev Raycho , Zlatanov Zlatko , Pashinski Chavdar
Published: October 2019

The application of Physical Vapor Deposition (PVD) hard coatings is one time-tested practice in the modern industry. Two of the main tendencies that promise a progress in this area are the combination of more chemical elements in one coating and the creation of nanolaminate structures. Since many combinations are possible in the design of the coatings, it could be expected they would have many different properties which are difficult to predict. In an attempt to work simultaneously in both of these directions, one nanolaminate Ti/TiN/AlTiSiN/(AlTiSiN/TiAlSiN)n/AlTiSiN coating was developed and its mechanical properties were tested. The results obtained give a reason to believe that it could be widely practically applied.
Lowering the noise level in the transport flows through reduction of the traffic barrier reflected noise
Authors: Kralov I , Nedelchev K
Published: October 2019

Reflected noise from traffic barriers usually leads to increasing of the noise level excited by the automobiles and trains. This effect requires the design of transport noise barriers for effective noise reduction behind them as well as to produce small level of reflected noise in source direction. This will effect in better noise environment for many passengers especially in case of busy traffic in rush hours. People affected by this effect are usually far more than the affected ones behind the barrier. One of the existed solutions is the use of expensive combined noise barriers with high degree of absorption. In this study a new passive transport noise barrier is designed, tested and analysed for a good reduction level of the reflected noise. It is done by appropriate design of the barrier profile performing source and reflected acoustic waves interference in small volumes near the barriers. The barrier construction, made by repeated, equally profiled elements, allows even the existence of acoustic bandgaps especially behind the barrier.
A method for determining the constant DC/AC motor power range and main technological spindle unit parameters
Authors: Guergov S
Published: October 2019

The article offers an original method for determining the constant DC/AC motor power range and basic technological parameters of the main spindle unit for multifunctional machine tools at the design stage. The method allows them to be determined, both in terms of the strength characteristics of the gearbox (or the strength characteristics of the system “machine-equipment-tool-work piece”) and in order to obtain the maximum spindle torque needed to ensure maximum machine productivity. The graphical interpretation of the method can be used both for designing new and for operating existing machines.
Selecting a location for establishing a rail-road intermodal terminal by using a hybrid SWOT/MCDM model
Authors: Stoilova Svetla D , Martinov Svetoslav V
Published: October 2019

The study proposes a methodology based on the combination of Strengths-Weaknesses-Opportunities-Threats (SWOT) analysis and Multi-Criteria Decision Making (MCDM) methods for selecting the most appropriate location for establishing an intermodal terminal. Analytic Hierarchy Process (AHP) and Preference Ranking Organization Method for Enrichment of Evaluations (PROMETHEE) are the MCDM methods used in the paper. The methodology contains four steps. In the first step we determine the alternatives variants of the location of intermodal terminal. In the second step the SWOT analysis have been applied to identify strengths, weaknesses, opportunities, and threats related to the surveyed system. The sub-criteria for each SWOT group have been defined. A total of 33 criteria are included in the study. Third step includes determination of weights of main criteria and sub-criteria by applying AHP method. The results of weights given in this step are used in the four step to ranking the alternative variants of the intermodal terminal location by using PROMETHEE method. The methodology has been approved for choosing the location of intermodal terminal in the city of Ruse. Five alternative locations of intermodal terminal have been studied. The results show that main importance of SWOT group has the strengths group criteria (0.471). It was found that the internal factors including the strengths and weaknesses have more important compared to the external factors including the opportunities and threats when studying the location of intermodal terminal. It was found that the main importance of all sub-criteria have the quantity of manipulated containers (9%), connectivity to road infrastructure (6%), rail connection with a port (5%) and average useful length of railway tracks used for loading/unloading activities (5%). The study shows that location that is situated in the place of the suspended Ruse-East railway yard is the best alternative for intermodal terminal location.
Study on the critical speeds of car’s movement with low and ultra-low profile tires in a turn
Authors: Taneva S , Ambarev K , Katsov D
Published: October 2019

This work proposes an improved algorithm for determining the critical speeds of car’s movement with low and ultra-low profile tires in a turn, where sliding of its axles occurs and overturning. The critical speeds are determined by the characteristics of the lateral slipping calculated for their critical normal loading. On the basis of the algorithm an interactive programming system in the MATLAB environment is developed. Graphic dependencies for the radius of the turn are presented, taking into account the slip of the tires with different speeds of a car Honda Civic Aerodeck 1.5iLS with low profile tires of size185/60R14. Results have been obtained on critical speeds against sliding in the front and rear axles and against the car’s overturning. Critical speed against overturning are determined in the absence of normal reactions for the inner steered wheels in a turn. The critical speeds of sliding are found to be lower than the overturning, and thus appear to be decisive.
The role of information and communication technologies as a part of business intelligence in improving the wealth of nations
Authors: Evseeva S , Kalchenko O , Plis K , Evseeva O
Published: October 2019

The paper is devoted to the task of determining the role of ICT as a part of business intelligence in improving wealth as the resultant factor in the development of the country and society. The authors consider the development of the wealth concept in a historical retrospective. The role of information and technologies as a part of business intelligence in the development of countries has been studied and generalized, digital transformation has been identified as the leading factor in ensuring the country’s economic growth. The paper presents data on the development of the digital economy for the period from 2010 to 2016 in developed countries and analyzes the state of the digitalization process in Russia. The authors put forward and test the hypothesis about the impact of ICT as a part of business intelligence on the Human Development Index, which determines the level of the country’s wealth according to the current concept adopted in the world community. The results of the research in Russia showed that there is a close relationship between the HDI as a result of the wealth indicator and the majority of indicators characterizing the virtual - digital environment - the Internet, computers, global virtual networks and mobile communications. In conclusion, the paper presents promising directions for further deeper analysis of revealing the degree of influence of each of the identified indicators, as well as the possibility of improving the country’s wealth based on the identified role of ICT as a part of business intelligence.
Data Management for Solving the Problem of Sequential Shaping Simulation
Authors: Mikheev V , Grechnikova A , Agafonova D , Klochkov Y
Published: October 2019

The publication presents the results of a study of the process of investing in the innovation of the Russian manufacturing industry (sample 2009-2017). Factors of economic efficiency of investment projects of the industry are revealed. It is proved that the efficiency of investment is determined by external factors, primarily by the level of economic concentration (CR3) of the market of innovative products. The coordination of the scientific result with the industry consolidation dynamics model (A.T. Kearney) is presented.
Microscopic and surface analyses of corroded Mg alloys
Authors: Marcheva Y , Loukaycheva M , Dimova B , Tsonev V , Kuzmanov N
Published: October 2019

Using optical and SEM microscopic observations and EDX analysis, the corroded surfaces of AZ91, AM50 and AE42 Mg-alloys in 3.5%NaCl were studied at condition of open circuit potential. Different surface composition, morphology, density and characteristics of the surface films were established. The corrosion potential, recorded for 5 days in the case of AE was studied and specific behaviour was observed. EDX analysis established the presence of Mg and Al in the corrosion products of the three alloys and Ce for AE42 and formation of oxides and/or hydroxides of these elements was assumed. A mechanism of dissolution of Mg alloys at OCP condition in NaCl solutions was discussed.
Innovation diffusion process in the Australian construction industry
Authors: Wipulanusat W , Panuwatwanich K , Stewart R A , Sunkpho J
Published: October 2019

Innovation diffusion process is an important component for construction companies to remain competitive in today’s changing business environment. The aim of this study is to examine how innovations in the Australian construction industry can be understood through innovation diffusion theories and empirical works. To achieve this goal, the author reviewed theoretical frameworks, and then analysed empirical works to shed light on the innovation diffusion in practice. The review found that effective innovation diffusion has played an important role in providing organizations with competitive advantages. From a socio-psychological perspective, leadership and team climate have had a direct effect on organizational culture, which indirectly impacts on innovation diffusion outcomes and business performance. Emphasizing the drivers and obstacles of innovation diffusion is also necessary to effectively develop a conceptual framework of innovation diffusion at project level which begins with knowledge and idea generation, and progresses to implementation and confirmation.
Design and construction monitoring and deformation analysis of super-large deep foundation pit
Authors: Zhou Junshu , Fang Guangxiu
Published: October 2019

Using the large and deep foundation pit of Metro Line 1 of Jinan west railway station as an example, this paper elaborated the design scheme of its retaining structure, formulated a monitoring scheme for foundation pit. In addition, through the real-time on-scene monitoring of horizontal displacement of pile top and pile body, and the monitoring data, we found the law of displacement of deep foundation pit supporting structure. The maximum horizontal displacement of pile body moves down gradually with the advancement of excavation support and the main construction. The maximum displacement occurs around 0.684H. This study has implications for similar engineering geological conditions of foundation pit supporting structure.
Model for predicting cost of rural road projects in Thailand
Authors: Lin Wai Phyo , Techapeeraparnich Wasaporn
Published: October 2019

Nowadays, construction cost plays an essential role in various projects, which are buildings, roads, railways, and bridges projects. Conceptual cost estimation in feasibility study is require high accuracy and less validation error especially in construction projects at early stages. The more improvement of estimation techniques, it would lead to the lesser problems of cost overrun, and extra expenses. This paper developed a cost estimation model for new constructed rural road projects. Considering the estimation methods for predicting the cost model, parametric method based on regression learner and NN method are applied. Previously, many researchers studied the cost applicable model by using various computer applications, so that this paper differed to compare these methods based on MATLAB. Accordingly, 44 road projects were compiled from DRR database, after that identifying the effective cost parameters referred on collected data. Subsequently, the data implementation process was focusing with regression learner based on automated regression training, and lastly, with NN toolbox concentrated on nftool for simulating the cost models. Another 7 road projects are tested with holdout validation process for these models. Due to this validation, we compare the predicted cost models within these methods. Finally, the developed models are reliable for not only the conceptual phase of future rural road projects but also the related construction fields can be recovered about the cost model creation.
Variation Prognostic Model on Port Infrastructures: Employment of Principal Component Analysis for Factor Extraction Instigating Disparity on Planning and Implementation Phase
Authors: Cabalag Maria Virginia , Silva Dante L.
Published: October 2019

Port is a transportation and communication marine infrastructure that is established for ship berthing and dockage, loading and unloading of passenger, storage of goods and other operational agendas that would impact a region or country in terms of social and economic aspects. Variation order is the modification on the design whilst construction is on-going. This is inevitable in a project. Through the utilization of Principal Component Analysis with a Cronbach’s Alpha of 0.930 and Kaiser-Meyer-Olkin Value of 0.763, nine components weighted, these are Actual Concreting and Precasting on-site for Structure formation, Meteorological Conditioning affecting Weather and Tides, Test Pile Apportionment on Both design and construction, Off-shore soil in-situ Properties, Behaviour and Suitability on fills, Inaccuracy of Geotechnical, Topographical and Hydrographical surveys, Project Release and Initiation Timing on engineering departments, Sudden unforeseen Turbulences during Pile Driving, Coordination of Planning and Implementation Departments, and Unavailability of Material Specification to Actual site from design. After extracting the regressor, assessment of completed port projects with variation and multiple linear regression was then employed to generate the model. The model had an R2 of 0.777 and an R of 0.882. Finally, the model was evaluated and has shown a significant value. Hence, a satisfactory breakthrough in an attempt to develop a model regarding variation order on port projects was established.
Development of construction blocks from alkaline activated basic oxygen furnace slag and Fly Ash
Authors: Sithole .N.T , Mashifana TP
Published: October 2019

The objective of this study was to develop basic oxygen furnace slag (BOFS) blended with Fly Ash (FA) based masonry blocks that can be used in building and construction. The effect of variation of FA, potassium hydroxide (KOH) concentration, curing temperature, solid-liquid ratio on the Unconfined Compressive Strength (UCS) was investigated. The optimum conditions for synthesis of BOFS/FA based masonry blocks was found to be 9 M KOH concentration, 20% Solid- liquid (S/L) and 1:5, FA:BOFS mixing ratio and curing temperature 80 °C. The masonry block prepared under aforementioned optimum condition achieved unconfined compressive strength (UCS) of 9.67 MPa. Characterization of the masonry blocks was done using X-Ray Diffraction (XRD) analysis, X-Ray Fluorescene (XRF) analysis. The major phase identified in XRD pattern for BOFS was larnite whereas for FA was glassy aluminosilicate. Optimum BOFS/FA masonry block had new phase which is zeolite (Philipsite) responsible for higher UCS of the construction block. The produced construction block met the minimum requirements for ASTM C34-13, C129-14a and South African standard (SANS227: 2007).
Sparse modeling for the geotechnical observation data
Authors: Kurita T
Published: October 2019

In the geotechnical engineering, it is a significant issue to construct the numerical models for simulation analysis based on the observation data. In this study, sparse modeling used as an effective modeling method in the field of machine learning and image processing was applied to the geotechnical engineering and its effectiveness was examined. Aa a case study based on the field observation data, the fused lasso which is a typical method of the sparse modeling was applied to model the velocity structure of the subsurface ground using the PS logging data. As a result of examination, it was found that simplified models can be obtained by increasing the value of the regularization parameter.
A review of the existing models to evaluate the ultimate bending moment of corroded reinforced concrete beam
Authors: Wang H J
Published: October 2019

Premature failure caused by steel corrosion is one of the most prominent durability problems of the reinforced concrete (RC) beams. Efficient evaluation of the ultimate bending moment of the corroded RC (CRC) beams is important for engineering practice. A great number of researches have been carried out, and various evaluation models have been proposed. However, the advantages and disadvantages of the existing models are still unclear, and less comparison studies among these models have been conducted. Therefore, the objective of this study is to review the existing models and clarify the merits and deficiencies of each model. Six empirical models for evaluating the ultimate bending moment of CRC beams are analyzed. Comparison study among these models is conducted based on 177 sets of experimental data collected from published literatures. According to the comparative analysis results, the advantages and disadvantages of each model are discussed. The comparison results show each existing model can exhibit good performance in evaluating a particular kind of experimental data. However, when the experimental data are out of the applicable range of each model, the existing empirical models may result in significant derivations.
Analysis of Geometry Effect on Laterally-loaded Large Diameter Bored Pile Deflection in Soft Soil
Authors: Tamara K , Ilyas T
Published: October 2019

A bored pile is one of the foundation type widely used in construction because of its design flexibility. For a laterally-loaded bored pile, additional pile and pile cap play an important role in influencing the lateral capacity. Large diameter bored pile with a 3.5 m diameter then proposed to substitute group piles in order to simplify the construction method aiming the same capacity. This study examines laterally-loaded large diameter bored pile deflection on soft soil as parametric studies with different pile length of 7 m, 14 m, and 21 m. Thick soft soil layer interpreted through soil testing data at Ancol, North Jakarta with the domination of silt. A thorough analysis of this system is modelled using a three-dimensional numerical method, PLAXIS 3D Foundation using push-over analysis that the deflection of laterally-loaded foundation reaches its tolerable deflection according to Indonesian National Standardization (SNI).
Effect of time dependent corrosion rate on residual capacity of corroded RC beam
Authors: Kioumarsi M , Baghban MH , Imperatore S
Published: October 2019

Corrosion is the most commonly severe defect in reinforced concrete (RC) structures and it mainly causes reduced rebar cross-section. The corrosion rate is the determining parameter of the progress of corrosion-induced damage. The present work is focused on the application of finite element (FE) analysis, using DIANA, to predict the residual capacity of reinforced concrete beam with different degree of corrosion. To this aim, existing experimental data is used to develop a FE model of corroded beams and to investigate their behaviour. This model is validated to predict the impact of time and current rate of corrosion on the residual load carrying capacity of corroded RC beams.
Development of new wood-concrete connectors
Authors: Khelil A. , Kiniagi C. , Boissière R.
Published: October 2019

The application of timber-concrete composites (TCC) connections in structures has increased over the past decades. The mechanical behaviour of these connections is largely influenced by the stiffness of the joints, both with regard to deformations and strength. This paper presents laboratory experiments and numerical simulations using ABAQUS performed on TCC with a new connector that has been developed in our laboratory. Collapse tests of Shear (push-out) tests, four-point bending tests on beams with different configuration and spacing are carried out within the serviceability load range to verify the slip modulus of connections which were derived from the push-out tests. Although the new connection is applied on notched timber, both experiments and 3D FEM simulations showed that the new connector exhibits stronger stiffness and has a significantly higher peak force performance.in constructing both.
The Potential of Enzyme in Reducing the Maturation Time and the Use of Ammonia in Concentrated Natural Rubber Latex
Authors: Wongkhat Jiraporn , Pattamaprom Cattaleeya
Published: October 2019

One of the most important parameters for indicating colloidal stability of concentrated natural rubber latex (CNRL) is the mechanical stability time (MST). The MST of CNRL after centrifugation is always low and slowly increases with storage time due to gradual hydrolysis of phospholipid on the surface of rubber particles into fatty acid soap. In this work, enzymatic approach was investigated to increase the colloidal stability of CNRL by using different grades and amounts of enzymes. The enzymes were tested with 2 grades of CNRL, which are the high-ammonia latex (HA latex) and low-ammonia latex (LA latex). We found that the MST of LA latex treated with 0.004% and 0.04% of Lipex reach the acceptable value (at least 600 sec.) within 14 and 10 days, respectively. In case of HA latex, the MST reached the acceptable value faster than that of LA latex (within 10 and 3 days at amount 0.004% and 0.04% of Lipex, respectively) while, the MST of commercial laurate-treated latex only increased slightly and could not pass the acceptable value after 31 days. In addition, the use of enzyme instead of laurate soap could reduce the use of ammonia in CNRL production.
Performance of Alum Sludge as partial replacement for cement adding superplasticizer
Authors: Vasudevan Gunalaan
Published: October 2019

The production of alum sludge from waste water treatment plant is increasing all over the world. Disposal of alum is becoming a serious environmental problem. Another alarming issue is attributed to the high usage of concrete in the construction industry where concrete is one of its main material. This will lead to increased cement production and emission of carbon dioxide emission. Hence, the research for replacement of cement by alum sludge is essential to reduce both the emissions of carbon dioxide and the disposal problem of alum sludge. An attempt has been made to investigate the use of sewage sludge ash as partial cement replacement in concrete. The alum sludge is incinerated at the temperature of 600 and a duration of 3hours. The incinerated alum sludge is sieved through size of 150. Four different percentages of 5%, 10%, 15% and 20% of alum sludge (AS) is used to replace the cement in the concrete. XRD and XRF tests were carried out to determine the similarity component present in the AS. Water absorption test and slump test has also been carried out to check the capacity of water absorption, durability and workability of the AS concrete. The compressive strength of AS concrete is also determined through rebound hammer and compression test. Result show that AS has the potential to replace cement as the major chemical component of AS is similar to that of cement.10% of AS concrete shows a lower absorption value than the control sample which shows that 10% SSA would have a better durability. However, an increase in the percentage of AS decrease the workability and compressive strength and yet, the 10% AS concrete possesses compressive strength higher than 25N/mm2 which can be applied in structural application. The findings suggested that the suitability of alum sludge concrete in different cement replacement ratio is applicable for different usage. The application of alum sludge in concrete will directly reduce the quantity of the cement used which also decreases the emission of carbon dioxide and solving the disposal problem of alum sludge.
Voids distribution of pavement filters subjected to permeating fines: a coupled DEM-statistical inference
Authors: Dassanayake Sandun M. , Mousa Ahmad , Kong Daniel
Published: October 2019

Granular soils in pavement systems, insidiously experience fines migration during their expected lifespan. Experimental monitoring of particles movement in a granular matrix is extremely challenging due to its concealed nature. Numerically modelling the permeation process demands a high computational power and requires additional conditions, which are frequently difficult to be obtained. This paper proposes an integrated numerical approach to estimate the conditional probability of observing a given voids ratio of a filter subjected to different fractions of permeating fines. The discrete element method (DEM) has been used for developing numerical samples of random voxels to estimate the void ratio distribution of the fines-free filter (i.e. virgin filter). Qualitative results obtained from a pilot scale experimental program have been presented to validate the hypotheses on which the novel methodology has been developed. The results further show that the distribution of the voids ratio in the filters subjected to permeating fines follow a gamma distribution, with a 0.9 probability of observing a voids ratio lower than the average value in the virgin filter.
Calculation of the maximum endurance of a small unmanned aerial vehicle in a hover
Authors: Hnidka J , Rozehnal D
Published: October 2019

Optimizing the flight performance, chiefly maximum endurance, of small unmanned aerial vehicles (SUAVs) relying on propellers powered by an electric motor/s as a form of propulsion is key challenge in SUAV development. Choosing the correct combination of propellers, electric motors and batteries is necessary and knowledge of characteristics of all three factors is of a great help. The paper presents a simple blade element model (BEM), which can be used to calculate the propeller performance characteristics. This model is further validated by measurements in the wind tunnel. The paper also presents measurements of electric motor and battery discharge characteristics. Finally, the paper presents a method of calculation of maximum endurance in hover.
Research of the impact of geometric unevenness of the railway track on the dynamic parameters of the railway rolling stock with two-stage spring suspension
Authors: Kuzyshyn A , Kostritsa S , Ursulyak L , Batig A , Sobolevska J , Voznyak O
Published: October 2019

The paper studies the possibility of using previously developed by the authors spatial mathematical model of the modern diesel train DPKr-2 for parameters determination, with the help of which the dynamic properties of the mechanical part are evaluated. The dependences of maximum accelerations of the body in the vertical and horizontal planes, the coefficients of vertical and horizontal dynamics both in the primary and in the secondary suspension on the speed of the car movement, the amplitude and the length of geometrical unevenness of the railway track were obtained. It is established at what speeds, depending on the parameters of geometrical unevenness of the railway track, the phenomenon of resonance and danger for the diesel train car movement appears. For a particular length of geometrical unevenness, the maximum permissible value of its amplitude over the entire range of speed movement, where the coefficients of vertical and horizontal dynamics in the primary suspension do not exceed permissible limits, has been studied. The adequacy of the mathematical model is checked by comparing the results obtained during calculations with the experimental ones.
Study of the prospect of k-Li lubricant for axle boxes of the railway rolling stock
Authors: Kravets Andrii , Yevtushenko Andrii , Kozar Leonid , Kravets Anna , Kovalov Maksym
Published: October 2019

The use of various types of plastic lubricants (such as LZ-TsNII, ZhRO, etc.) in the axle boxes of locomotives, cars and track machines in the Ukrainian railway network causes technological inconveniences at the stage of procurement, supply and regulation of this process, moreover, their operational capabilities do not quite satisfy modern operating conditions of axle boxes of the railway rolling stock. The paper proposes to solve this problem by using a single brand of modern multi-purpose lubricant on lithium complex basis (k-Li) – MZT – in axle boxes of all types of railway rolling stock. The presented results of the comparative analysis of the physical and chemical properties of the mentioned lubricants demonstrate that the MZT lubricant completely meets the operating conditions of the axle bearings and can provide their high-quality lubrication under any conditions of operation. The tribological studies of lubricants on frictional testing machines, with simulation of their operation with rolling friction and sliding friction, demonstrated that anti-wear, antifriction and anti-cuffing properties of the MZT lubricant are much better than those of LZ-TsNII and ZhRO lubricants. It has been found out that the properties of the MZT lubricant are most effectively used under high load in friction pairs. The paper presents the results of testing the MZT lubricant in the actual conditions of operation of locomotives, railway cars and multiple unit rolling stock, which demonstrated its high efficiency and operation capacity.
Methods for forming interfacial heat-mass exchange surface in flowing air contact with water
Authors: Averkin A.G. , Eremkin A.I. , Kiselev S.O.
Published: October 2019

A review of methods for forming interfacial heat-mass exchange surface in contact devices for air steam treatment is given. An effective method for creation of heat-mass exchange surface in air flow contact with water in the course of adiabatic wetting in air conditioning systems is proposed: by use of a plate head-piece with a mechanical vibration exciter. A method of defining area of the interfacial heat-mass exchange surface for these conditions is developed on the base of number of transfer units. The criterion equations to describe heat and mass transfer which occur when a plate head-piece with a vibration exciter is used for adiabatic air wetting are obtained. Use of a plate head-piece with vibration exciter as a contact device reduces energy consumption due to reduction of aerodynamic resistance of the air path and process intensification.
Aluminate spinel-based SHS pigments for fire-resistant protective and decorative coatings
Authors: Radishevskaya N I , Nazarova A Yu , Kasatsky N G
Published: October 2019

In the work, color spinel-based inorganic pigments obtained by the SHS method are used in fire-resistant protective and decorative aluminophosphate-bonded coatings. X-ray diffraction (DRON-UM1 diffractometer, filtered CuKα radiation) and IR spectroscopic (Nicolet 5700 FTIR spectrometer) analyzes revealed that the coating contained AlPO4, Al2(PO3)3 and Al(H2PO4)3 phases and spinel. Thermal analysis performed on an SDT Q600 thermal analyzer showed a slight mass loss related to the polymerization of phosphates and the formation of P2O7
2-anion in the range of 500-550 °C, which was also confirmed by IR spectroscopy. The color of protective and decorative coatings is maintained at temperatures of up to 1000 °C. Optical studies (Axiovert 200M) showed that color coatings subjected to heat treatment at 300 °C have a uniform structure that does not contain cracks, and therefore they can be used for metal, concrete and brick surfaces.
Use of Additive Technologies to Optimize Design of Classifying Devices
Authors: Romashev A O
Published: October 2019

The article considers perspectives of the use of additive technologies to optimize the design of classifying devices. A brief overview of the solutions developed using 3D printing of for mining industry is given. It is stated that creation of models is impossible without knowledge of the laws of distribution of flows and expressions describing them. For this purpose, the influence of the pulp viscosity on classification in a hydrocyclone on an experimental unit has been studied. A modified Plitt model was proposed to predict the separation grain. The proposed model takes into account the pulp viscosity and predicts the size of the boundary grain more accurately.
Creation mechanism of Devil’s Staircase surface and unstable and stable periodic orbits in the anisotropic Kepler problem
Authors: Shimada T , Sumiya K , Kubo K
Published: October 2019

In the two-dimensional Anisotropic Kepler Problem (AKP), a longstanding question concerns the uniqueness of an unstable periodic orbit (PO) for a given binary code (modulo symmetry equivalence). In this paper, a finite-level (N) surface defined by the binary coding of the orbit is considered over the initial-value domain D
0. A tiling of D
0 by base ribbons of the surface steps is shown to be proper, i.e., the surface height increases monotonously when the ribbons are traversed from left to right. The mechanism of creating a level-(N+1) tiling from the level-N tiling is clarified in the course of the proof. There are two possible cases depending on the code and the anisotropy. (A) Every ribbon shrinks to a line as

N
→
∞

. Here, the uniqueness holds. (B) When future (F) and past (P) ribbons become tangential to each other, they escape from the shrinking. Then, the initial values of a stable PO (S) and an unstable PO (U) sharing the same code co-exist inside the overlap of the F and P non-shrinking ribbons. This corresponds to Broucke’s PO. When the anisotropy is high, only case A is observed; however, as the anisotropy decreases, a bifurcation of the form

U
(
R
)
→
S
(
R
)
+
U
′
(
NR
)

occurs along with the emergence of a non-shrinking ribbon. (Here, R and NR denote self-retracing and non-self-retracing POs, respectively). We conjecture that, from a classification based on topology and symmetry, case B occurs only for odd-rank, Y-symmetric POs. We report two applications. First, the classification is applied successfully to the successive bifurcation of a high-rank PO (n = 15), where the above bifurcation is followed by

S
(
R
)
→
S
′
(
R
)
+
S
″
(
NR
)

. Second, enhancing the sensitivity to the co-existence of S and U POs through ribbon tiling, we examine the high-anisotropy region. A new symmetry-type POs (O-type) are found and, at γ = 0.2, all POs are shown to be unstable and unique. An investigation of 13648 POs at rank 10 verifies that Gutzwiller’s action formula works with amazing accuracy.