bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical simulation of material failure in single point incremental forming process
Authors: Rusu G P , Popp M O , Oleksik M , Rodean C
Published: October 2019

The sheet metal parts obtained through single point incremental forming process show a thinning and also there is a high possibility of material failure. In order to avoid the failure of the material during the process, it is a good practice to use numerical simulation through finite element method to prevent this phenomenon. The aim of this paper is to investigate the prediction of the failure moment of the aluminium sheet metal using various failure criteria. Commonly used failure criteria are: Tresca or maximum shear stress criterion, von Mises yield criterion, Hill yield criteria and various invariants of the Cauchy stress tensor. For the numerical simulation of the single point incremental forming process, the semi-finished part is discretized using shell elements which allow determination of material thinning and also it is possible to observe the moment of material failure. This paper will treat also the influence of the wall angle over the moment of material failure.
Robust design application for optimizing ABS fused filament fabrication process: A case study
Authors: Tsiolikas A , Mikrou T , Vakouftsi F , Aslani K E , Kechagias J
Published: October 2019

The current paper is a case study of optimizing fused filament fabrication (FFF) process using robust design. FFF process is a low cost 3d printing process that uses ABS (Acrylonitrile-Butadiene-Styrene) filament in order to build progressive layer by layer, physical prototypes. Four (4) parameters having three levels each ones is used (Deposition angle, Layer thickness, Infill ratio, Infill pattern). The quality indicator that used for the optimization process is the dimensional accuracy. It was found that the layer thickness is the most important parameter in the reported experimental area.
An internal combustion engine visualization physical prototype applying digital manufacturing
Authors: Kitsakis K , Aslani K E , Vaxevanidis N , Kechagias J
Published: October 2019

Nowadays computers have invaded all levels of production, thus improving the quality and quantity of products. Digital manufacturing involves all tools for design, simulate, and programming machine tools in order to manufacture prototypes or tools for production use. This project is a case study of digital manufacturing for prototyping of an internal combustion engine visualization model. Solidworks is used for 3D modeling of all parts of the engine. Fused filament fabrication (FFF) is used for physical modeling of the engine parts. Pros and cons of the manufacturing process are discussed. It is concluded that parameter optimization is needed in order to improve quality indicators of the 3D printed engine parts.
Simulated 3-axis versus 5-axis Processing Toolpaths for Single Point Incremental Forming
Authors: Racz G S , Breaz R E , Oleksik V S , Bologa O C , Brîndașu P D
Published: October 2019

Accuracy and productivity of the parts manufactured by single point incremental forming (SPIF) are influenced by the proper selection of toolpaths. CAM software packages are often used for generating the toolpaths for the process. Literature survey have revealed that contour curves and spatial spirals are the most used toolpaths for SPIF. These toolpaths are generated using 3-axis approaches, meaning that the tool axis is maintained parallel to the vertical axis. The 3-axis approach was justified using 3-axis CNC milling machines as the main technological equipment for SPIF. However, nowadays, the wide spreading of both 5-axis CNC milling machines and industrial robots, with far superior kinematic capabilities justifies the research of more complex toolpaths for unfolding SPIF. In this paper, 5-axis toolpaths, where the tool is oriented by normal to machining surfaces are proposed and compared with 3-axis toolpaths, by means of simulation.
Selection of effective equipment for shotcrete
Authors: Stepanov M A , Kaitukov B A
Published: October 2019

The analysis of technological equipment used in the shotcrete. Defines the main technical characteristics of mixer applications in the preparation of the mixture. With regard to the technical parameters and characteristics of the mixture determined the Reynolds number. Between the Reynolds number and the rotation frequency of the drum there is a positive correlation, increasing the dependence has a linear character. The Reynolds number is found that mode-mixing of the concrete is turbulent. Analysis of technical characteristics of sprayed plants were allowed to establish the dependence of their output power
Computational fluid dynamics in RTM method of the carbon composites molding
Authors: Paździor P , Szczepanik M
Published: October 2019

The article focuses on simulating flow of epoxy resin in injection mold with carbon fiber fabric inside. Performed simulations were based on the process of manufacturing composite elements using modern RTM method. RTM method is used in production of high-end and sports car parts, and other lightweight products requiring high strength. It consists in injecting the resin under pressure into a closed mold with reinforcement. One of major problems in this method is providing adequate flow of the resin in injection mold and a complete supersaturation of reinforcement with a thermosetting resin. These aspects depend strongly on the direction of the fibers in the carbon fabric and porosity of the reinforcement. Information about proper construction of the mold and influence of fiber orientation and porosity can be obtained by numerical simulations using CFD commercial software Moldex3D. Research was based on actual process of manufacturing car mirror covers. Analysis of obtained results focused on the impact of changes in process input parameters. In particular, parameters such as the porosity and direction of fibers in the reinforcement were investigated. Test results are compared in terms of the degree of reinforcement supersaturation in the mold. Based on performed tests, appropriate conclusions were drawn.
Studies and Research on the Stress – Strain Analyses of the Polyethylene Pipe-Fitting Assemblies Accidentally Subjected to an External Force
Authors: Avrigean E , Filip S M
Published: October 2019

The paper aims at analyzing the behavior of the polyethylene pipe - fitting assembly in the case of accidental stress due to the accidentally occurring external forces (mechanized excavation in the assembly area). The study will identify the necessary computing relationships and the minimum value of the force to which the analyzed assembly breaks, as well as some solutions for avoiding these accidental stresses. A three-dimensional model of the assembly will be made by applying the external forces on three main directions, following the maximum stresses for the same value of the external force. Also, a welding of a polyethylene pipe-fitting assembly will be carried out and it will be subjected to three stresses on the three directions so that a parallel can be made between the results. The study will also observe the way in which the temperature is distributed throughout the assembly and the areas where the obtained temperature reaches the highest value during welding.
Study of the opto – electronic coupling in some complementary metallic – dielectric metamaterials used as biosensors
Authors: Ionescu D , Apreotesei G
Published: October 2019

Using of the metamaterials improves the sensitivity and resolution of sensor devices, having multiple applications in biomedicine (imaging, biomarkers, telemedicine, etc.). We have studied the effect of different types of ordering in the lattices of nanostructures inside the metamaterial samples. Structures consisting of metallic atoms (tens of nanometers diameter) arranged relative periodically in a dense dielectric matrix have been analyzed by simulation methods. We have focused on the opto-electronic coupling phenomena and the interactions between plasmons and the applied field. A study of the electron scattering processes was performed, the simulational data being used to calculate the reflectance and permittivity in function of the wavelength, in the range of 500…2300 nm. The electromagnetic properties of the metamaterial samples depending on particles shape, dimensions and on the reports between metallic inclusions dimensions and the dimensions of the dielectric matrix where are included have been studied and new configurations were proposed in order to improve the metamaterial sensors performance. We expect an increment in the response to the exciting field of about 7%, in a more dense state of spins characterising the new material samples.
Microwave absorption and reflection properties of a composite dielectric absorber
Authors: Shorstkii I , Sosnin M
Published: October 2019

Microwave assisted technologies and its application are widely used in different research fields. One of the main difficulty of this area is to design a treatment chamber. The aim of this paper is to measure power absorption and calculate average surface microwave power density of composite dielectric materials, based on plant particles. Obtained microwave-absorbing characteristics of composite plant material can be used in microwave assisted processes and high-performance microwave treatment chambers design to facilitate the research in microwave assisted drying and extraction. The research includes experiments with different positioning of the composite materials from reflective metal screen inside the chamber-waveguide.
SEM, EDS and XPS studies of AC & DC PEO coatings obtained on titanium substrate
Authors: Rokosz K , Hryniewicz T , Dudek Ł , Pietrzak K , Raaen S , Malorny W , Ciuperca R
Published: October 2019

The porous coatings may be fabricated on titanium substrate by Plasma Electrolytic Oxidation (PEO), known also as Micro Arc Oxidation (MAO), under AC or DC regimes. The obtained surfaces were characterized by Scanning Electron Microscope (SEM), Energy-dispersive X-ray spectroscopy (EDS), and X-ray Photoelectron Spectroscopy (XPS). This work has discussed the influence of electrolyte composition and of PEO type (AC-PEO or DC-PEO) on chemical composition of fabricated porous coatings as well as on their surface stereometry. The recorded results show clearly that the external porosity and roughness of obtained surfaces as well as metal-to-phosphorus ratios are different for different solutions and PEO processes, but for all PEO surfaces the bindings energies of titanium (Ti 2p), oxygen (O 1s), phosphorus (P 2p) may suggest that all the top nano-layers consist of Ti4+ and groups PO4
3–, and/or HPO4
2–, and/or H2PO4
–, and/or P2O7
2–.
Comparative analysis of the morphology of doped zinc and copper oxide nanopowders
Authors: Modan E M , Ducu C M , Moga S G , Negrea A D , Plăiaşu A G
Published: October 2019

Nano-oxides attracted the attention of the reserchers due to their numerous applications. From this point of view, the development of new synthesis methods has become equally important for industry. The use of solar energy can become one of the ecological methods of obtaining nano-powders. Our paper presents the comparison of the morphology of nanopowders of Al-doped zinc oxide and Mn-doped copper oxide, obtained by physical vapour deposition using solar energy (SPVD), at different pressure and solar flux. The morphological characterization of doped oxide nanopowders synthesized by SPVD was performed by scanning electron microscopy.
Analysis and impact of different ambiguities in industrial technical product drawings
Authors: Oezden R , Popa M S , Danho S
Published: October 2019

The declaration of conformity of a workpiece to the technical product drawing is absolutely essential in modern industrial product development. Today, the dimensioning of the technical product drawing features many ambiguities, which are indicated unconsciously by the construction and development departments. Not least, the reason for this can be found within the steady changes of the international standards, which are controlled by the system of Geometrical Product Specification (GPS). As soon as the planning, concept and development stage within classical industries is largely completed and a no longer modifiable drawing status has been attained, suitable tools have to be built on the basis of the technical product drawing in order to start production. Once the tools are available, the results of the pilot series can be assessed via initial sample analysis. During this stage, the assessment via measurement technology equipment ensues in order to ascertain the requirements of the technical product drawing. The assessment of the negative measurement values ensues within the project team, which is difficult since it can yield many divergent assertions. This paper analytically shows the impact of ambiguities resulting from technical product drawings and contributes to the solution of a precise geometrical quality assurance through its clarity.
Path planning optimization for mechatronic systems with the use of genetic algorithm and ant colony
Authors: Tsagaris A , Mansour G
Published: October 2019

Path planning optimization of mechatronic systems is a very important field of research that has been growing rapidly in recent years. Coordinate measuring machines (CMM), robotic arms, CNC machines, are often using a big amount of points to control the path planning. Within these efforts, some encouraging results are presented in this work on the optimization of path planning. By integrating ant colony techniques into genetic algorithm, path optimization can be reached up to 50% instead of the simple genetic algorithm. At the same time, the calculation of the optimal solution that makes this technique even more efficient is accelerated. From measurements made in a simulation model, reductions in overall trajectories were recorded up to 40% in cases where the number of points exceeded 500 while the optimal path planning time was reduced by up to 20%. In real-system implementation these values are slightly reduced due to the real-time execution of the movements. This integration makes the proposed technique particularly attractive in cases where are path planning between a large number of points and the calculation time is required to be small.
Analysis of shape deviations of technical polyamide workpieces in different defined time intervals
Authors: Aclan M , Popa M S , Oezden R
Published: October 2019

Engineering grade plastics gain importance across the industry and have become indispensable today. Machine operators must concern themselves among others with environmental and manufacturing influences that can affect the geometrical properties of plastic articles daily. In practice, these are declared as check gauges in the inspection drawing and are checked in accordance with quality standards. Based on experience, plastic articles made from polyamide start to grow after a certain time span. Even manufacturers of plastic granulate indicate this in their fact sheets. Here, the geometry of the plastic articles themselves plays a crucial role, especially in how far it can be altered. Additionally, in globally aligned companies with several production facilities, certain ecological influences such as temperature and humidity are different. The effect this has on plastic articles in terms of growth has been investigated in a different research paper [1]. This paper is primarily concerned with the evaluation of geometrical alteration by means of warpage formation. Thereby, an experimental part is demonstrated and constituted in comparison with two different climate simulations, of standard climate and one of extreme climate, over the course of a defined period of two months.
A comparative study about some application packages used in Photogrammetry
Authors: Nedelcu D , Gillich G-R , Malin-Tatian C
Published: October 2019

Photogrammetry is the technique used to convert a real geometry of a part into a 3D computer file starting from images. The paper aims to compare some free and commercial application packages used in Photogrammetry, based on the same images taken from an axial turbine blade. The blade geometry can be included in a bounding box with the following dimensions: 233 x 125 x 82 mm. The geometrical entities generated with these applications will be compared through Cloud Compare software.
Determination of the shape of a beam obtained by fused deposition material with general loads
Authors: Stănescu N D , Beșliu–Gherghescu M L , Rizea A
Published: October 2019

In this paper, we develop a general procedure for the obtaining of the shape of a beam obtained by FDM and having arbitrary loads. The beam is subjected to bending loads and because of its small elasticity modulus the approximate theory presented in the strength of materials cannot be applied. We used the general equation for the deformation of the beam resulting non-linear equations for the bending moment, the shear force, the rotation, the elongation and the deflection. These relations are solved by numerical methods. An example will highlight the theory.
State machines simulator for distributed decision system
Authors: Savu T , Jugravu B A
Published: October 2019

The amount of computing power assigned to the intelligent components of a production system must be justified by the benefits brought following the decisions these components are taking. The paper proposes a state machines and messages exchange based model for developing simulators used to estimate the system’s behavior and performance in different configurations. A simple system was modeled and simulations were performed for different numbers of electric transporters in the system, different charging times and for different degrees of independence concerning the decisions taken by the manufactured products. It was possible to determine the most effective number of transporters, a value which is increasing, as expected, with the charging time. A second conclusion was that allowing the manufactured products to decide themselves concerning the transporter to use at a certain moment does not necessarily increase the overall system’s performance.
Particular features of the load-bearing elements of rigging lifting systems
Authors: Verschinskiy A , Gorokhov P , Shubin A
Published: October 2019

The problems of deformability of a large-capacity metal support beam are considered. The results of experimental studies and numerical analysis of beam deformability are presented. These studies take into account the specific interaction of stresses arising from the impact of loads on the product at operation, and residual welding stresses. Recommendations on stabilization of form deflections of metal construction of beams are given.
Modelling and improvement of the design of hinged centralizer for casing
Authors: Shatskyi I , Vytvytskyi I , Senyushkovych M , Velychkovych A
Published: October 2019

We have researched an important problem for the oil-and-gas field, which is the problem of centralizing of cases in wellbores with a complex profile. Usually this problem is solved by equipping the case in problematic areas with special centralizing devices. Centralizers have mutually competing requirements: low stiffness in order not to slow down the descent of the case into wellbore and high stiffness in order to provide proper clearance gap for high-quality cementing of the annular space. The aim of the paper is to solve this problem by means of the construction of a hinged-rod centralizer, additionally equipped with a thrust ring. To model the arch-shaped link of the centralizer, the classical theory of the flat rods is used. On the basis of analytical solution of contact problems with unilateral connections, we investigated the stress-strain state of the rod in two cases: before and after the interaction with the axial obstruction. We have determined the non-linear dependencies between the contact force and the mutual approach of the case and the wall of the wellbore, and also the expressions of the acceptable contact loadings that provide structural integrity of the construction.
Analysis of the influence of the aspect ratio on the vertical axis wind rotor performance
Authors: Rabei I , Guțu M
Published: October 2019

The aspect ratio (AR) of the vertical axis wind rotors defined in this paper as the ratio between the height and the diameter of the rotor is an important factor when considering the performance of the rotors. However, choosing the most appropriate AR when designing a wind rotor, based on literature review, is not fully reliable as different sources point out contradictory data. This paper presents an analysis regarding the influence of the AR on rotors performance based on experimental data.
Adaptive drive and adaptive mechanisms of technological machines
Authors: Lemeshko M A , Kozhemiachenko A V , Iliev A G
Published: October 2019

Examples of the development and application of mechanisms and machines endowed with the properties of self-adjustment (adaptation) to changing operating conditions, in particular machines for mining operations, are presented. It is shown that adaptive mechanisms and machines have a number of advantages in variable operating conditions. At the same time, the area of knowledge on the creation and use of adaptive machines and mechanisms to date, remains poorly understood. The purpose of the work is to present the concept of adaptation of mechanisms and machines to operating conditions, the Executive bodies of which work with variable loads. The results of the paper can be useful for machines and mechanisms design with self-adjusting and self-regulating characteristics. Adaptive mining tunneling, drilling machines and adaptive cutting tools reveal the concept of adaptive machines and mechanisms characteristics to changing operating conditions. The principle of operation of an adaptive drilling machine designed for drilling operations is described. It is shown that the feedback between the torque of the resistance to rotation on the drill rod and the force of the rod feeding on the face is carried out through the force-torque connections with the optional use of electronic automation tools.
Study to increase the quality of the scientific research process
Authors: Ghimisi S S , Nicula D
Published: October 2019

At present, increasing attention is paid to the quality of products and processes in different fields of activity. Currently, universities and other institutions with research activities scientifically, are increasingly concerned with the implementation of quality management through different one’s methods and tools. Quality Management provides a range of tools that can be used to find solutions when it comes to improving quality. In this paper the authors present a study on the tree diagram determination, for quality improvement the scientific research process. The important measures to be taken have been identified for the successful completion of a scientific research process. To increase the quality of the scientific research process, has grouped the identified measures and thus leads to an orientation to three specific objectives: the organization’s management adequately assures the necessary resources; the head of the research collective adequately organizes the research activity; the research collective chooses and applies an adequate research methodology on the theme. A measure from the third specific objective is considered to be a secondary objective, and for it specific actions are provided which constitute level 4 of the tree diagram. A diagram has been developed that includes: the general objective, the specific objectives, the measures identified for the achievement of the objects. The paper presents a tree diagram that can be used in the quality management within the frame of the organizations which desire to improve the quality of the scientific research activities. The use of this diagram offers the advantage to examine in a chronological and logical sense the causes which determine the quality of a scientific research process
A neural network application for the estimation of the probability of leaving a working place
Authors: Ene A , Stirbu C
Published: October 2019

This article is about a topical theme, namely that of leaving a workplace, by an employee. The paper proposes that on the basis of input data, to make an estimate of the probability of leaving a job by a particular employee. In order to make such a prediction, the authors of the paper propose the use of artificial intelligence elements, namely artificial neural networks. Artificial neural networks have the ability to generalize, based on a history. The probability of abandonment of a job, is determined empirically, because there is not an exact mathematical formula. When we do not know the equation after which a particular process takes place, to make an estimation, neural networks are excellent tools.
Use of structural design and analysis software for master degree education in mechanical engineering fields
Authors: Debeleac C
Published: October 2019

In this paper the author deals a presentation of modern teaching methods applied in higher education process (master degree) at Dunarea de Jos University of Galati, Engineering and Agronomy Faculty of Braila. This paper describes main courses that are laid out in order to achieve the desired goals and haw the virtual laboratory experiments should fit into the courses to promote interdisciplinary understanding. A practical example of master degree studies will be provided as a case of good practices in supporting of National education process to become harmonized with European Area of Higher Education.
Development of the production system through lean management tools
Authors: Plakhin A E , Al-Ogaili S M M , Semenet I I , Kochergina T V , Mihajlovskij P V
Published: October 2019

Lean management or lean manufacturing is a fairly new practice for Russian enterprises. The introduction of lean management systems into Russian realities began in the 2000s. The main problem is that domestic enterprises, starting from the state of the economy and mentality, cannot use foreign experience without changes. In this paper, the main tools of lean manufacturing are considered and a step-by-step method of system implementation is proposed using the example of Uralelectromed JSC. Currently, only large Russian enterprises have the practice of introducing lean production systems. In this paper, we consider the method of implementing the system on the example of a small group of employees of the enterprise. This technique can be successfully applied to small enterprises. The aim of this work was to develop a concept for the development of the production system through lean management tools.
A graphical software application for the ergonomic design of a working place
Authors: Ene A
Published: October 2019

A working place has to be designed in order to offer with minimum cost adequate working conditions. The labor yield is much influenced by environmental measurable parameters like temperature, humidity, noise and the luminosity at the working place. In this paper we present a graphical application that could be used to investigate which is the best combination for the values of these input parameters from the point of view of work efficiency. The relationship between the input parameters and the work efficiency is nonlinear. Therefore, we used a neural network to model these nonlinearities. The neural network is simulated using Java programming language.
Costs calculation of an work accident in a production hall for metallic confections
Authors: Cojocaru D , Solomon Ghe , Dijmărescu M C
Published: October 2019

Work accidents and occupational illnesses are subjected to a strict and distinct part of the legislation regarding health and safety at work. Each year, in the all world, a significant number of workers get ill, are injured or lose their lives at work. From this situation results, first of all, the generation of human costs, and second, a number of financial costs. Therefore, the total cost of work accidents and occupational illnesses includes both financial costs and an assessment of the human costs which will be borne by economic organizations and businesses. Work accidents, generated and quantified in Romania, lead to economic losses that are not negligible. Therefore an expert procedure needs to be adopted to determine their cost and consequently to determine the impact they have on the enterprise or organization. This paper presents a cost calculation model, using the method PREVENT-MATRIX, in the case of a work accident in a production hall for metallic confections.
The development of a methodology of learning to use simulation in the analysis of production system performances
Authors: Gavriluță A , Gavriluță C A , Pascu I , Neacșu C
Published: October 2019

Considering the dynamic environment in which the present companies work, global market, fierce competition, frequent changes of techniques and technologies, more diverse demand from clients, changing norms and ethics, it is a pressure that rises. To cope with these complex factors, the modelling and simulation of production systems became a main approach in the middle of 20th century. To develop a model and to later use it in simulation is an “artistic” balancing of opposites that demand finesse and skills; on one side the model must be easy to use, that meaning it must involve a level of abstraction from reality, on the other side the model must be a faithful representation of the system it mimics. Therefore, in this article we will develop a learning platform for a methodology to use the modelling and simulation in the analysis of production systems performances. The platform and the methodology will be later experimented and validated, leading to a higher level of research quality.
Experimentation of a methodology to use modelling and simulation in the analysis of performances of an automotive industry production system
Authors: Gavriluță A , Gavriluță C A , Neacșu C , Pascu I
Published: October 2019

The simulation is almost always used as an integrated part of a system design process, as method to identify the improvements of an existing process, to evaluate an already developed model to find alternative solution for it or to compare working hypothesis. It represents an experimental technique that allows experimentation on models of the real system created using a specific simulation language. The knowledge accumulated during the experimentation on the model can be useful and applicable on the real system. Considering that, when it comes to talking about modelling and simulation it is talked about building a model of a real system and the experimentation possible on it. In this paper we will experiment a methodology to simulate the operating mode of a production system from the automotive industry, formed of several interconnected stages. The techniques and instruments used to make the activities in this methodology are in the fields of flow analysis and comparative analysis.
Risk-cost model for FMEA approach through Genetic algorithms – A case study in automotive industry
Authors: Belu N , Ionescu L M , Rachieru N
Published: October 2019

Failure mode and effects analysis (FMEA) is a proactive method for eliminating the potential failures emerged from various systems such as products, processes, designs, or systems. FMEA utilizes the risk priority number (RPN) to determine the risk priority order of failure modes. RPN is calculated by multiplying the values of three risk factors: severity (S), detection (D) and occurrence (O) Although FMEA techniques are used in different industries in many situations when multiple experts give their opinions about one failure mode, the risk evaluations can be vague and imprecise, which could arise conflicting evidence that is hard to manage. This paper presents a risk-cost analysis model that uses Genetic algorithms to generate an FMEA for the raw materials and finished parts reception process, in automotive industry. Unlike the classic FMEA analysis, in our model the risk factors D and O are determined by resources cost analysis involved in their improvement. Here comes the Genetic algorithm that will determine the optimal cost under an acceptable risk. The proposed solution uses modern information technology for data acquisition (complex event processing), automation of analysis process (artificial intelligence) and long-term support for quality staff in FMEA analysis (real time and batch data analytics).
Numerical study on the influence of suspension damping on the bogie vertical vibration
Authors: Dumitriu M , Gheți M A
Published: October 2019

The paper presents a study on the influence of suspension damping (SD) on bogie vertical vibrations generated by vertical track irregularities. The study is based on the results of the numerical simulations developed on the basis of a linear model with seven-degree of freedom of the bogie-track system, that takes into account the rigid vertical vibration modes of the bogie – bounce and pitch, vertical displacements of the wheels and rails, and the wheel-rail contact elasticity. The bogie vibration behaviour is assessed based on the dynamic response of the bogie chassis, expressed as the power spectral density of the vertical acceleration (PSD acceleration) at three reference points – at the bogie chassis centre and over the axles, and root mean square of vertical acceleration (RMS acceleration). It is highlighted the main characteristics of the bogie vibration behaviour according to the SD in correlation with the speed and quality of the railway track.
The influence of multi-speed transmissions on electric vehicles energy consumption
Authors: Rențea C , Oprean M , Bățăuș M , Frățilă G
Published: October 2019

The electric vehicle (EV) represents an important option in the process of road transport decarbonization. The limited driving range and high speed performances are obstacles for EV customer acceptance. While until now the emphasis for the improvement was on battery, power electronics and motor technologies, it becomes obvious that the transmission must be also addressed. The extensively used single-ratio transmission can satisfy the demands of city use, but do not attain other important functional needs that are ensured by conventional and hybrid electric vehicles. The aim of this paper is to analyse the energy consumption of an EV with multi-speed transmission in five test cycles among which Worldwide Harmonized Light duty Test Cycle (WLTC) is considered. This study is done by means of simulation using a model specifically developed in a simulation environment. In the interest of analysing the performances in several test cycles, one needs to compare global parameters such as: vehicle speed fluctuation (VSF), overall transmission efficiency, energy consumption ratio (ECR). A comparison between test cycles is made taking into consideration a relative parameter (ECR). The correlation between ECR and VSF is investigated as well. The results are also compared with those produced for a vehicle with diesel engine.
The influence of the roof frame on the stiffness of a bus structure
Authors: Iozsa M D , David V C , Manea A M
Published: October 2019

In order to respect the more stringent emissions regulations, the weight of the bus must be optimized. The bus structures weight can be lowered by decreasing the thickness of the its components. By doing so, the stiffness of the structure will be affected. A deeper understanding of how different elements influence the stiffness is necessary, for optimizing the bus structure. The aim of this paper is to study the influence of the roof frame on the stiffness of the bus structure. Two cases are studied, one in which the roof frame forms a common body with the side frames, and one in which the roof frame is a standalone component, attached to the side frames via connecting elements and steel plates. The stiffness and the weight of the two bus structures are compared. Using a standalone roof frame gives a better flexibility for optimizing the structure, by choosing a different thickness or material for the frame, increasing the stiffness and reducing the weight.
An analysis of the required energy consumption to tow a classical passenger train with an electric locomotive
Authors: Arsene S , Popa G
Published: October 2019

Ensuring a transport system to increase the mobility of goods and people is one of the great challenges of the modern world. This mobility directly affects the environment. At international level, the regulations adopted in recent years are increasingly stricter with regard to reducing the level of carbon dioxide (CO2). In this context, in many countries, the rail transport system has drawn attention to its performance. This paper seeks to carry out an estimation of electricity consumption in a railway sector in Romania. Taking into account the constructive characteristics of the towing section, the motor vehicle (locomotive) and the at vehicles towed (wagons) that are part of the train, an estimate of the electric power consumption required for the train movement can be made.
Telemetric System for Silesian Greenpower’s Vehicle
Authors: Stalica A , Błachuta M , Baier A , Żur P , Kołodziej A , Konopka P , Komander M
Published: October 2019

The paper presents stages of creating a measurement system for a light-weight electric vehicle of the Silesian Greenpower team. The aim of the work was to design a measuring device and mobile application for drivers and the team. The system itself consists of a measuring device, applications for Android and Windows. The purpose of the device was to provide information about the car in real time. The collected data is saved and displayed on the driver’s phone. At the same time, the data is stored in a database, which allows the whole team to observe current parameters. Working of the measurement system has been described in the paper. Screenshots from individual applications, a specification of selected sensors and source code of the created applications have been presented. The summary of the project are graphs showing the smooth operation of the measurement system during races taking place on the Rockingham circuit in the UK.
Designing and verifying the concept of Silesian Greenpower electric bolide structure
Authors: Baier A , Komander M , Nowak A , Konopka P , Kołodziej A , Żur P
Published: October 2019

The purpose of the following paper is to demonstrate the thought processes behind the design and verification of the electric race car structure. The developed structures were modelled in the CAD environment of Siemens NX 10.0 program. The main aim of inventing different solutions was to improve the characteristics of the car. These characteristics include, for instance, aerodynamic drag and gearbox friction. After the framework was established, work on the shape of the body began. The body alterations are understood as reducing the overall width of the car, decreasing the cross-section area and tilting the sides of the sheathing in order to minimise the generated aerodynamic drag. All elements were verified computationally to check whether they can be improved by altering their geometry. Main condition upon which every modification was made was to switch from the previous belt transmission to the newly designed chain transmission. The most significant change in the frame was reducing the back-section width in order to accommodate the chain transmission. Furthermore, it was required to enable easy switching of the transmission from chain to belt. Next step of the project was adding the mechanism enabling the tilting of wheels rotational axis in relation to the ground.
An overview on the Miller-Atkinson over-expansion thermodynamic cycle
Authors: Niculae M , Clenci A , Iorga-Simăn V , Niculescu R
Published: October 2019

The tightening of pollution and greenhouse gas regulations generated a change in the homologation procedure, i.e., a far more dynamic driving cycle and the testing of the vehicle in real driving conditions are now part of the type approval procedure. In order to cope with these new challenges, the car manufacturers must adopt new technologies such as Miller-Atkinson cycle, which lately started to grow in popularity. This being the context, our paper’s main purpose is to present the particularities of this over-expansion thermodynamic cycle, mainly underlining its effect on the internal aerodynamic of the spark ignition engine.
Simulation of heat exchange between a digital instrument transformer and its environment for operation in emergency and unfavorable weather conditions
Authors: Gotovkina E E , Lebedev V D , Parfenov G I , Smirnov N N , Tyutikov V V
Published: October 2019

Reliable functioning of electric power grids to a large extent depends on the serviceability of each unit in the given power system, subject to the impact of various unfavorable factors, namely grid operation mode and weather conditions, such as elevated ambient temperatures, insolation and no-wind. These environmental parameters have a significant negative impact on the process of heat removal from electrical equipment, which may result in its overheating and breakdown. ISPEU staff have developed and put into operation innovative design digital current and voltage instrument transformers. The purpose of the present study is to examine the impact of insolation, ambient temperature and emergency operating modes on the thermal state of transformers. A mathematical model of heat exchange for a 6(10) kV transformer was developed and verified with the results of physical experiments conducted in an environmental chamber. Heat exchange between the transformer and its environment was simulated for a July day in Sochi in nominal and emergency operating modes, and also with various values of heat conductivity of electrical insulation sealant used. It was discovered that maximum influence on transformer thermal state is exerted by self-heating of instrument resistors at elevated voltage levels.
Comparison of electric powers measured with digital devices relative to powers associated with distinctive physical phenomena
Authors: Zajkowski K , Rusica I
Published: October 2019

The article discusses the methods of measuring electrical powers in general-purpose digital devices. Based on the described algorithms, the measured values were classified and compared with the powers determined from the Currents’ Physical Component (CPC) power theory for single-phase and three-phase circuits. The results of calculations for an example measuring circuit were compared. The criticism of the measurement methods used today is presented. The method of measuring the CPC powers has been outlined.
Hardware error estimation model of signal reception in the task of monitoring the tightness of gas engineering systems
Authors: Malysheva A A , Gnezdilova O A , Pavlova A A , Ovsienco A S
Published: October 2019

We propose a solution of the task of improving the accuracy of estimates of gas flow in gas engineering systems. Performed an analytical review of works of leading scientists in the field of the theory of supply. It has been established that the question of control and to prevent gas leaks remains relevant now. It is proved, that for engineering systems use gas for domestic purposes, where low pressure set leaks quite difficult due to the large spread of points of vulnerability, also the greatest risk are low-intensity gas leaks, that hardly controlled by hardware due to accounting errors. The analysis of constructive solutions to the engineering supply systems of low pressure. Installed geometric variety. Accepted hypothesis about the impact of the quantity and type of butt joints leak gas pipeline systems engineering in General. An algorithm is presented for vulnerability assessment elements engineering gas supply systems for leaks. The mathematical model for the evaluation of measuring error of parametric parameter of gas flow in the system. The technique for monitoring the tightness of gas systems engineering with the rationale for selecting the method of evaluation of error results.
Developing affordable housing for low-income households in developing countries using participative payment
Authors: Berawi M A , Aulidtyo R , Miraj P , Gunawan
Published: October 2019

The government of Indonesia attempt to increase the standard living of the low-income households by providing affordable housing. The concept is implemented in Jakarta-the capital city of Indonesia as the pilot project in the past years. However, the operation faces several obstacles, and one of them is the debt of rental fees from the households from 2013 to 2017 about US$ 2,013,888.89 for all affordable housing exist in Jakarta. This research attempt to evaluate the potential business that can be implemented on the site to improve the payment capability from users. Marunda Affordable Housing in North Jakarta and Cipinang Besar Selatan in East Jakarta will be used as the case studies. Pairwise comparison and life-cycle cost approach are adopted to achieve the targeted objectives. The result shows a different type of business that can be applied to both case studies. One is related to marine processing industry, while the other is suitable with the manufacturing industry. Both business proposals generate a significant rate of return above minimum attractiveness rate of return in the related industry.
Developing port-city conceptual design to improve regional industry competitiveness
Authors: Berawi M A , Muljono T E , Miraj P , Gunawan
Published: October 2019

As an archipelago country, Indonesia continues to face significant problems with port infrastructures and coastal area including financial shortage, complex bureaucracy not to mention development priority. Port-city is one of a city concept aims to facilitate the regional development by taking port as the hub for economic activities and mobility. This research use Dumai port in Riau Province, the Republic of Indonesia as the case study to evaluate the potential implementation of the port-city concept. Two methods are being used to evaluate the project feasibility namely life-cycle cost approach and public-private partnership scheme. It will regulate the division of responsibility between identified parties. The result shows three components to develop the concept including the port, industrial area and supporting infrastructure. This concept may generate 10.37% of the internal rate of return. This research also suggest public-private partnership scheme to generate optimum division of responsibility between each parties in the project.
The Permeability of Portland Cement-Stabilized Clay Shale
Authors: Diana W , Hartono E , Muntohar A S
Published: October 2019

Research on the effect of Portland cement on the improvement of problematic soil has been extensively studied in many years and many places. Soil stabilization using cement has improved the strength and durability, enhanced the performance of the problematic soil such as clay shale. However, most studies in the field of Portland cement-stabilized soil have only focused on strength and durability improvement and the information on permeability characteristic has not adequately provided. This study aimed to investigate the effect of Portland cement stabilization on the consistency limits and permeability of the clay shale. The Portland cement content was varied from 2% to 10% by weight of dry soil. The stabilized clayshale specimens were cured for seven days before the testing. Constant head permeability method (method A) of the ASTM D5084 was used to determine the coefficient of permeability. The result shows that both the liquid limits and plastic limits decrease with increased Portland cement content, hence the plasticity index of the soil-PC mixing decrease. The permeability coefficient of the soil mixed with 2% of cement increased about 14 times greater than the untreated soil. Increase in cement content tends to decrease the coefficient of permeability.