Mechanical Engineers Research Articles

Novel Fabrication of 3-D Cell Laden Micro-Patterned Porous Structure on Cell Growth and Proliferation by Layered Manufacturing.

This study focuses on developing and characterizing a novel 3-dimensional cell-laden micro-patterned porous structure from a mechanical engineering perspective. Tissue engineering holds great promise for repairing damaged organs but faces challenges related to cell viability, biocompatibility, and mechanical strength. This research aims to overcome these limitations by utilizing gelatin methacrylate hydrogel as a scaffold material and employing a photolithography technique for precise patterned fabrication. The mechanical properties of the structure are of particular interest in this study. We evaluate its ability to withstand external forces through compression tests, which provide insights into its strength and stability. Additionally, structural integrity is assessed over time to determine its performance in in vitro and potential in vivo environments. We investigate cell viability and proliferation within the micro-patterned porous structure to evaluate the biological aspects. MTT assays and immunofluorescence staining are employed to analyze the metabolic activity and distribution pattern of cells, respectively. These assessments help us understand the effectiveness of the structure in supporting cell growth and tissue regeneration. The findings of this research contribute to the field of tissue engineering and provide valuable insights for mechanical engineers working on developing scaffolds and structures for regenerative medicine. By addressing challenges related to cell viability, biocompatibility, and mechanical strength, we move closer to realizing clinically viable tissue engineering solutions. The novel micro-patterned porous structure holds promise for applications in artificial organ development and lays the foundation for future advancements in large soft tissue construction.

The contribution of the Stephenson Company, engine manufacturers to the genesis of the British railway industry c.1823-1840

The paper investigates the Stephenson Company’s contribution to genesis of the railway industry by exploring its business model in its formative years. The Company capitalised on a well-developed business and technological infrastructure in the North-east of England that provided the building blocks for the creation of a new industry. It gained from its linkages with two social networks which provided it with a financial safety-net during the locomotive development phase and the mechanical expertise it required: the closed Quaker network and the regional network of colliery and mechanical engineers. Whilst bridging between and across these social networks facilitated the Company’s development, it was not central to its strategic decision-making. This was shaped by the externalities of market conditions, which the Com­pany sought to influence by producing a viable product that would convince customers of its utility, and investors of the potential gains to be had through investing in railway construction.

A CFD-FEM analysis for Anaconda WEC with mooring lines

Anaconda wave energy converter (WEC) [1] is a typical flexible tube WEC design. In the past decade, the hydro-elastic performance of Anaconda model has been studied through experiments [2-3] and reduced-order numerical simulations [4-5]. However, to date, most of the undertaken research assumes that both ends of the tube are fixed, neglecting mooring lines that exist at designed conditions. The tube is allowed to move freely head to waves when mooring lines are considered. This is evident by an experiment conducted by Checkmate Flexible Engineering Ltd., where they observed a significant heave motion of Anaconda WEC, which may impact the dynamic response of WEC and further the energy conversion [6]. In our previous work [7], supported by the EPSRC project BASM-WEC (No. EP/V040553/1), a coupled numerical analysis tool using computational fluid dynamics (CFD) and finite element method (FEM) has been proposed to perform a numerical study for an Anaconda WEC model without considering mooring lines.In this paper, the coupled fluid-structure interaction (FSI) analysis tool [7] based on CFD-FEM method will be used to investigate Anaconda WEC with mooring lines. To account for the effects of free motion of WEC, we develop a sub-module to be embedded into the existing tool. The fluid and structure are solved by a two-phase CFD solver developed based on OpenFOAM and a three-dimensional FEM code CalculiX, respectively. The strong coupling between OpenFOAM and CalculiX is achieved by a multi-physics coupling tool preCICE.For the flexible tube, a commercial Natural Rubber material is studied. The hyper-elastic model YEOH is utilized to describe the nonlinear behaviour of material, and the model constants are calculated from the bi-axial tests. With the tool developed, numerical simulations are performed for different given regular waves. The flow details, velocity and pressure variation, structure deformation and stress distribution will be fully examined to better understand energy conversion performance of Anaconda WEC with mooring lines.
 References[1] Farley F J M D, Rainey R C T. Distensible tube wave energy converter: U.S. Patent 7,980,071[P]. 2011-7-19.[2] Chaplin J R, Heller V, Farley F J M, et al. Laboratory testing the Anaconda[J]. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2012, 370(1959): 403-424.[3] Heller V, Chaplin J R, Farley F J M, et al. Physical model tests of the anaconda wave energy converter[C]//Proc. 1st IAHR European Congress. 2000.[4] Farley F J M, Rainey R C T, Chaplin J R. Rubber tubes in the sea[J]. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2012, 370(1959): 381-402.[5] Babarit A, Singh J, Mélis C, et al. A linear numerical model for analysing the hydroelastic response of a flexible electroactive wave energy converter[J]. Journal of Fluids and Structures, 2017, 74: 356-384.[6] Checkmate Flexible Engineering, https://www.checkmateukseaenergy.com/, accessed 15th December 2022.[7] Huang Y, Xiao Q, Idarraga G, et al. Numerical analysis of flexible tube wave energy converter using CFD-FEA method[C]//International Conference on Offshore Mechanics and Arctic Engineering. American Society of Mechanical Engineers, 2023 (submitted).

Badanie czynników warunkujących stopień zużycia i zniszczenia zębów w mechanizmach przekładni zębatych

Transmission gears are very widely used in the modern construction of the machine. Even though electrical transmissions are used, mainly mechanical transmissions are widely used in the machine building industry as they are independent and better than other transmissions. Distributing power between the transmission mechanisms and working units of various machines, by changing the angle of momentum by adjusting the speed of the parts, it is possible to change the type of movement, turn the mechanism on and off, and change the direction of the transmission mechanisms. One of the most widespread types of transmission technology is gear transmission. Tens of thousands of kilowatt-hours of gears can be transmitted. The advantages of gear transmission in comparison with others are their ability to maintain their reliability and long-term functioning of the teeth, high value of the working coefficient (0.90–0.99), simple construction, lack of special service, simplicity of the transmission number and compactness of dimensions. The missing aspects of these transmissions are high precision in their preparation and installation, and low noise level. The main criterion for the working ability of the closed gear transmissions is the contact endurance of the active surface of the tooth. For this reason, the main dimensions of the transmission are determined by the contact tension and by teeth bending.

РЕСУРСОЗБЕРІГАЮЧИЙ БЕЗПЕРЕРВНИЙ ОПТИЧНИЙ КОНТРОЛЬ ТЕМПЕРАТУРИ РІДКОГО МЕТАЛУ В МЕТАЛУРГІЇ ЕНЕРГЕТИЧНОГО МАШИНОБУДУВАННЯ

The article is devoted to the problem of the most effective and non-alternative continuous optical temperature control of metallurgical aggregates in machine building metallurgy. The aim of the article is to develop and investigate the technologies of continuous temperature control on the base of classical and spectral (multicolor) thermometry. To achieve thе aim, the next methods have been used: analysis of literature sources; experimental investigations of influence regularities of sighting zones, time of tapping, intensity of mixing and liquid metal temperature on one color radiation temperature of liquid metal in visible and infrared spectrum ranges under industrial conditions; statistical processing of the results of direct and indirect measurements with their errors estimation. It has been found the main role of thermometry in the metrological support structure of metallurgical plants. The production volumes of world machine building metallurgy have been analyzed, particularly, the part of metallurgy of energy machine building in it. Metallurgical equipment to be used for liquid metal obtaining and treatment has been classified from thermometric position. The stability of radiation characteristics of liquid metal in cupola, arc and induction furnaces has been investigated under conditions of different impact factors. The methodical errors of optical temperature measurements of liquid metal during tapping from cupola and arc furnaces on the base of classical energy thermometry have been estimated. In special determined сases these errors don’t exceed 1,0–1,5% with confidence level 0,997. Under another conditions these errors reaches 8% and this fact stimulates transition to the spectral thermometry. With the use of modern elemental base, the technologies of spectral measurements of temperature and emissivity have been developed. The technologies include: symmetric-wave, two-color compensative, as well as based on nonlinearity equation of emissivity spectral distribution. The temperature measurement errors of new technologies are lower than the same ones of known spectral, as well as classical energy and spectral ratio thermometry in 2,3; 11,7–20,0 and 6,1–7,6 times. Keywords: metallurgy of machine building, continuous optical temperature control, cupola furnace, arc furnace, classical and spectral thermometry.

Actual problems of creating digital twins of machine engineering products in terms of durability assessment

The global digitalization of production opens new opportunities for predictive diagnostics of the technical condition of mechanical engineering products. The issues attributed to assessing their technical condition, primarily to the determination of the residual life of mechanical engineering products, are considered. Currently, a class of virtual models, digital twins of the residual life is distinguished. Apart from the functions of monitoring and predicting the stability of structures, they can possess a feedback and control the durability by simulating and optimizing the real technological process, taking into account the possibility of achieving the limit state of the structure. The problems of existing methods of assessing the durability in time and frequency domains are considered in detail from the viewpoint of using the residual resource of structures as the basis of an algorithmic support of digital twins. We also marked the possible variety of obtaining initial data for assessing the durability, namely fatigue diagrams of materials for different types and schemes of loading. The fatigue diagram is greatly affected by the loading process (regular, random or mixed), while in the actual work the non-stationary random loading prevails. The methods used for assessing the durability of non-stationary loading are poorly studied and often resolve into simplification of a non-stationary process. The study is focused on non-stationary loading processes, since the creation of digital twins implies a continuous analysis of the durability of the structure for real operational loads. Other problems that can arise when developing digital twins of structures are also considered and discussed.

Vertically integrated project based method applied to small satellite technology development

Small satellite missions and technology development presents a unique platform for preparing undergraduate engineering students for future careers. University based small satellite projects provide students access to hands-on opportunities to apply theory learned in classes through computational analysis, hardware experimentation, and product design. They also allow students to gain project management skills and see systems engineering and design life cycle from a perspective few semesters long courses and lectures can provide. Since 2017, undergraduates have been involved in the Purdue University team investigating the Film Evaporation MEMS Tunable Array (FEMTA), a novel microthruster that evaporates ultra-pure deionized water to generate thrust and is intended for use as active attitude control on small satellites. This technology development project is well suited for including undergraduates, as the system operation can be easily understood by a student with only an introductory understanding of fluid mechanics. Undergraduates initially investigated single axis rotation control of a model CubeSat and now focus a suborbital payload to test the propellant management system. Undergraduates earn degree credit for aiding the faculty and graduate students in this long-term, multidisciplinary, and vertically-integrated – including students from freshmen to seniors -research project team. Vertically integrating allows students to participate for their entire undergraduate studies, while providing projects with stability and a knowledge base shared amongst many students. While this method can be applied to projects that are not aerospace related, small satellite projects allow students to add a breadth and depth of subject matter to their professional development. This project has included mechanical engineers, aerospace engineers, electrical and computer engineers, and computer science majors. This environment grants students the ability to learn new perspectives and problem-solving techniques from their peers. By requiring students to earn degree credit for project work, students become more invested and develop better professional habits such as proper documentation and communication. Student testimonials have cited this project as an asset while talking with company recruiters and for graduate school applications. The same methods developed on the FEMTA project are also being applied to the Purdue student team that is developing the camera system for the NASA Solar Cruiser mission, with similar success.

COOPERATION BETWEEN GOSNITI
 AND CHGAU IN RESEARCH ACTIVITIES

The end of the 90 – the beginning of the 2000 s can be characterized as a period in which there was a critical situation related to the financing of research in agroengineering universities. An important role in the system of agroengineering training was played by educational and experimental farms, which performed the function of technical equipment of the educational and scientific-production process. With the termination of the allocation of budget allocations for the development of educational and experimental farms, the number of scientific developments has decreased. (Research purpose) The research purpose is studying the experience of organizing new forms of support for educational, scientific and production activities based on the integration of the GOSNITI research Center with the Chelyabinsk State Agroengineering University on the basis of the Department of Machine Repair, initiated by Vyacheslav Ivanovich Chernoivanov. (Materials and methods) The main directions and results of the activity of Sector 18 related to the issues of improving the technical equipment of the agro-industrial complex of the Southern Urals are considered. (Results and discussion) It is shown that the main activities of Sector 18 were the development of technologies for the non-disassembly extension of the post-repair life of internal combustion engines and agricultural machinery units using nanomaterials; development of technologies for sharpening the working bodies of tillage agricultural machines using electrophysical processing methods; improvement of the production process with the development and implementation of QMS according to GOST R ISO 9001-2008 during the modernization of tractors and combines; renovation repair and technological equipment; restoration of parts by electrophysical methods. The important contribution of scientists to improving the quality of education in the training of engineers of technical service of agricultural machinery was noted. (Conclusions) The training of competitive mechanical engineers in universities with the necessary professional knowledge, competencies and practical skills is impossible without close scientific cooperation of the graduating departments of universities with the relevant laboratories of leading research institutes.

Integration of Deep Learning for Automatic Recognition of 2D Engineering Drawings

In an environment where manufacturing precision requirements are increasing, complete project plans can consist of hundreds of engineering drawings. The presentation of these drawings often varies based on personal preferences, leading to inconsistencies in format and symbols. The lack of standardization in these aspects can result in inconsistent interpretations during subsequent analysis. Therefore, proper annotation of engineering drawings is crucial as it determines product quality, subsequent inspections, and processing costs. To reduce the time and cost associated with interpreting and analyzing drawings, as well as to minimize human errors in judgment, we developed an engineering drawing recognition system. This study employs geometric dimensioning and tolerancing (GD&T) in accordance with the ASME (American Society of Mechanical Engineers) Y14.5 2018 specification to describe the language of engineering drawings. Additionally, PyTorch, OpenCV, and You Only Look Once (YOLO) are utilized for training. Existing 2D engineering drawings serve as the training data, and image segmentation is performed to identify objects such as dimensions, tolerances, functional frames, and geometric symbols in the drawings using the network model. By reading the coordinates corresponding to each object, the correct values are displayed. Real-world cases are utilized to train the model with multiple engineering drawings containing mixed features, resulting in recognition capabilities surpassing those of single-feature identification. This approach improves the recognition accuracy of deep learning models and makes engineering drawing and image recognition more practical. The recognition results are directly stored in a database, reducing product verification time and preventing errors that may occur due to manual data entry, thereby avoiding subsequent quality control issues. The accuracy rates achieved are as follows: 85% accuracy in detecting views in 2D engineering drawings, 70% accuracy in detecting annotation groups and annotations, and 80% accuracy in text and symbol recognition.

Discipline differences in mental models: How mechanical engineers and automation engineers evaluate machine processes

AbstractInterdisciplinary collaboration frequently comes into play when existing problems cannot be solved by one discipline alone. However, the interlocking of contributions from different disciplines is by no means trivial. This exploratory study examines one foundation of successful teamwork, namely shared mental models. To this end, we compared the contents of mental models between members of different but interdependent disciplines who collaboratively solve knowledge‐intensive, creative tasks. Five automation and five mechanical engineers were recruited from a company that produces packaging machines. In semi‐structured interviews, participants reported their approach to evaluating the process behavior of a packaging machine, and their mental models were represented in concept maps. Quantitative analyses revealed that the maps of automation engineers were smaller than those of mechanical engineers. In qualitative analyses, the focus on different levels of abstraction and on contents from the two disciplines was examined. Automation engineers represented a large proportion of rather abstract machine functions, whereas mechanical engineers additionally represented the physical implementation of these functions. The disciplinary focus also differed in the sense that automation engineers mainly attended to automated machine processes, while mechanical engineers attended to both mechanical and automated processes. Overall, automation engineers' focus was narrower than that of mechanical engineers. We explain these results by considering typical tasks and reasoning processes in both disciplines, and discuss how shared mental models can aid the integration of different disciplinary perspectives, for instance, during Systems Engineering.

Analysis of the Frictional Performance of AW-5251 Aluminium Alloy Sheets Using the Random Forest Machine Learning Algorithm and Multilayer Perceptron.

This paper is devoted to the determination of the coefficient of friction (COF) in the drawbead region in metal forming processes. As the test material, AW-5251 aluminium alloys sheets fabricated under various hardening conditions (AW-5251-O, AW-5251-H14, AW-5251-H16 and AW-5251H22) were used. The sheets were tested using a drawbead simulator with different countersample roughness and different orientations of the specimens in relation to the sheet rolling direction. A drawbead simulator was designed to model the friction conditions when the sheet metal passed through the drawbead in sheet metal forming. The experimental tests were carried out under conditions of dry friction and lubrication of the sheet metal surfaces with three lubricants: machine oil, hydraulic oil, and engine oil. Based on the results of the experimental tests, the value of the COF was determined. The Random Forest (RF) machine learning algorithm and artificial neural networks (ANNs) were used to identify the parameters affecting the COF. The R statistical package software version 4.1.0 was used for running the RF model and neural network. The relative importance of the inputs was analysed using 12 different activation functions in ANNs and nine different loss functions in the RF. Based on the experimental tests, it was concluded that the COF for samples cut along the sheet rolling direction was greater than for samples cut in the transverse direction. However, the COF's most relevant input was oil viscosity (0.59), followed by the average counter sample roughness Ra (0.30) and the yield stress Rp0.2 and strength coefficient K (0.05 and 0.06, respectively). The hard sigmoid activation function had the poorest R2 (0.25) and nRMSE (0.30). The ideal run was found after training and testing the RF model (R2 = 0.90 ± 0.028). Ra values greater than 1.1 and Rp0.2 values between 105 and 190 resulted in a decreased COF. The COF values dropped to 9-35 for viscosity and 105-190 for Rp0.2, with a gap between 110 and 130 when the oil viscosity was added. The COF was low when the oil viscosity was 9-35, and the Ra was 0.95-1.25. The interaction between K and the other inputs, which produces a relatively limited range of reduced COF values, was the least relevant. The COF was reduced by setting the Rp0.2 between 105 and 190, the Ra between 0.95 and 1.25, and the oil viscosity between 9 and 35.

The Ever-Expanding Toolbox

Abstract Enhancements to engineering software platforms are purported is to make life easier for mechanical engineers, who are increasingly being asked to do more on shorter timelines. While these upgrades are powerful, it is uncertain whether working engineers know what’s available and how to use it.

Cooperation and Competition in Synchronous Open Quantum Systems.

Synchronization between limit cycle oscillators can arise through entrainment to an external drive or through mutual coupling. The interplay between the two mechanisms has been studied in classical synchronizing systems, but not in quantum systems. Here, we point out that competition and cooperation between the two mechanisms can occur due to phase pulling and phase repulsion in quantum systems. We study their interplay in collectively driven degenerate quantum thermal machines and show that these mechanisms either cooperate or compete depending on the working mode of the machine (refrigerator or engine). The entrainment-mutual synchronization interplay persists with an increase in the number of degenerate levels, while in the thermodynamic limit of degeneracy, mutual synchronization dominates. Overall, our work investigates the effect of degeneracy and multilevel scaling of quantum synchronization and shows how different synchronizing mechanisms can cooperate and compete in quantum systems.

Impact of the interface on the fatigue life of steel-based explosively welded heterostructured plates

Melted zones, microcracks, shear bands, and elastic incompatibility of explosively welded materials are features that may initialize cracks at the interface and reduce fatigue strength. This study aims to determine the effect of interfacial defect-like structures on the fatigue strength of explosively welded corrosion-resistant plates. Cyclic axial loading was applied to seven distinct layer-by-layer compositions of Ti Gr 1, Zr 700 alloys, and carbon steels. The interfacial wave height as a metric of potential fatigue life influencing factors along with measured strain amplitude was applied as the input quantities for the Machine Learning based model, i.e. the Gaussian process for regression (GPR). This is a novel and successful application of GPR to estimate the effect of interfacial wave height on the fatigue life of explosively welded plates. For the first time, the effect of the interface feature on fatigue life was estimated quantitatively. The Digital Image Correlation technique was applied to measure the field of cyclic strain for the purpose of verifying if a single strain amplitude is representative of a heterostructured plate. It was found that interfacial wave height is an important feature and its increase by 100 µm reduces the fatigue life of analysed plates by 36%. Additionally, to validate the applicability of explosively welded plates to engineering structures under cyclic loading, the experimental fatigue lives were compared with the design curve of the American Society of Mechanical Engineers (ASME) code.

Computational physiological models for individualised mechanical ventilation: a systematic literature review focussing on quality, availability, and clinical readiness

BackgroundIndividualised optimisation of mechanical ventilation (MV) remains cumbersome in modern intensive care medicine. Computerised, model-based support systems could help in tailoring MV settings to the complex interactions between MV and the individual patient's pathophysiology. Therefore, we critically appraised the current literature on computational physiological models (CPMs) for individualised MV in the ICU with a focus on quality, availability, and clinical readiness.MethodsA systematic literature search was conducted on 13 February 2023 in MEDLINE ALL, Embase, Scopus and Web of Science to identify original research articles describing CPMs for individualised MV in the ICU. The modelled physiological phenomena, clinical applications, and level of readiness were extracted. The quality of model design reporting and validation was assessed based on American Society of Mechanical Engineers (ASME) standards.ResultsOut of 6,333 unique publications, 149 publications were included. CPMs emerged since the 1970s with increasing levels of readiness. A total of 131 articles (88%) modelled lung mechanics, mainly for lung-protective ventilation. Gas exchange (n = 38, 26%) and gas homeostasis (n = 36, 24%) models had mainly applications in controlling oxygenation and ventilation. Respiratory muscle function models for diaphragm-protective ventilation emerged recently (n = 3, 2%). Three randomised controlled trials were initiated, applying the Beacon and CURE Soft models for gas exchange and PEEP optimisation. Overall, model design and quality were reported unsatisfactory in 93% and 21% of the articles, respectively.ConclusionCPMs are advancing towards clinical application as an explainable tool to optimise individualised MV. To promote clinical application, dedicated standards for quality assessment and model reporting are essential.Trial registration number PROSPERO—CRD42022301715. Registered 05 February, 2022.

Ecosystem approach to the strategic management of foreign trade activities of machine–building enterprises

The article presents the results of the analysis of the main trends in the innovative development of domestic machine–building enterprises, the export potential of domestic special–purpose products and machine–building products in general is considered. The main trends that must be taken into account in the strategic management of foreign trade activities of machine–building enterprises are identified. The necessity of forming an ecosystem, which includes both directly machine–building enterprises and enterprises that provide their activities, is shown, as well as its characteristics and role in improving the efficiency of strategic management of foreign economic activity in this sector of the economy. An ecosystem approach to the strategic management of foreign trade activities of machine–building enterprises is presented. The main functions and results of the functioning of the ecosystem formed in the machine–building complex are formulated. The main factors that must be taken into account when choosing strategies for foreign economic activity in the machine–building complex are determined. The direction of private and complex alternative solutions is revealed, which should include the strategy of foreign trade activities implemented in the machine–building complex. In view of the presence of many different alternative solutions related to the strategic management of foreign trade activities of machine–building enterprises within the ecosystem, the necessity of forming a controlling system is justified, which involves the creation of a single consultative structure with the participation of representatives of foreign partner companies.

Financial and credit support of market-oriented management of transport engineering enterprises

Purpose. To determine the priorities of the financial and credit support of transport machine building taking into consideration the needs of the national economy, state of marketing environment, and requirements of corporate management. Methodology. The information basis of the study is represented by the statistic data formed according to the classification of economic activity types KVED-2010 in terms of section C “Processing industry”, divisions 29 “Production of motor vehicles, trailers, and semitrailers” and 30 “Production of other transport means”. The research methodology involves analysis of dynamics and structure of production volumes, net profit of the transport engineering enterprises, formalization of trends, evaluation of credit capacity of the industry, and marketing and financial diagnostics. Findings. Key trends in the development of the transport machine-building market within the period of 2012–2020 are generalized: reduction of total production volumes and identification of subindustries-drivers of its growth. Structural shifts in the national economy owing to the growing specific weight of the production of motor vehicles, trailers, semitrailers in terms of prevalence of other transport means (first of all, railway and air ones) are identified. The priorities of financial and credit support of the transport machine building are specified taking into account the needs of civil national economy (railway locomotives and rolling stock, motor vehicles, air- and spacecraft, accompanying facilities) and military economy (military vehicles). To evaluate the objects of credit support, it is proposed to use a concept of credit capacity of an enterprise as its ability of accumulating banking credits on its balances in terms of certain currencies, terms, designated purpose, interest rates etc. as well as their timely servicing and payment. Originality. The scientific and methodological foundations of determining the priorities of financial and credit programme of the transport engineering enterprises are substantiated in the context of market-oriented corporate management, whose advantages are as follows (compared with the current ones): highlighting the time lags of production crisis and after-crisis renovation in the context of industries; determining structural shifts in the field of transport machine building, and identifying the economic activity types being leaders or outsiders in the sphere of financial and credit support of the expanded reproduction on this industry; defining polarization of business entities, being different in their size, according to the financial state and solvency with the focus on competitive advantages or crisis. Practical value. Proposals as for restructuring the activities of the transport engineering enterprises are substantiated basing on marketing diagnostics of the state of their internal and external environment, threats and possibilities in terms of war time, Ukraine’s getting a status of the member for the EU accession, and post-war renovation of the economy. In the framework of market-oriented management of the transport engineering enterprises, certain tendencies in the financial and credit support of their complex innovative development are substantiated.

ANALISIS PENGENDALIAN KUALITAS CACAT DIMENSI PADA HEADER BOILER MENGGUNAKAN METODE FMEA DAN FTA DI PT. IHI POWER SERVICE INDONESIA (IPSI)

IHI Power Service Indonesia is a company engaged in the Boiler Pressure Part Industry (Fabrication) in every production activity it always strives to produce quality products according to ASME standards (American Society of Mechanical Engineers). Production results are less than the maximum. In the 2020 period the total production was 28,527 tons and the number of defects was 364 tons, in the 2021 period the total production was 22,703 tons and the number of defects was 301 tons. The author uses the Failure Mode And Effect Analysis (FMEA) method and the Failure Tree Analysis (FTA) method. From the results of data processing using a Pareto diagram based on the RPN value obtained from the FMEA method, the dominant type of defect is obtained, namely Hole Distance with an RPN value of 364.5 and Dimension Length with a value of 351.17, then analyzed using FTA, at the proposed improvement stage it is proposed to use the 5W+1H method. Factors that cause defects include inaccurate and faded measuring instruments, rare maintenance on radial drilling machines and blades that are rarely replaced. Proposed improvements to reduce defects include requesting replacement of measuring instruments, carrying out regular maintenance of radial drilling drilling machines, holding shift schedules for operators, conducting training for operators.

EEG-BASED COGNITIVE LOAD INDICATORS IN CAD MODELLING TASKS OF VARYING COMPLEXITY

AbstractAs an initial step towards a better understanding of cognitive load in computer-aided design (CAD), the herein presented study investigated cognitive load imposed on 24 mechanical engineers during two CAD modelling tasks of intentionally different complexity levels. The cognitive load has been rarely studied in the CAD context, which resulted in the lack of understanding if and how the EEG-based indicators available from the literature reflect the changes in cognitive load imposed on engineering designers in CAD activities. Therefore, cognitive load was measured and analysed using three EEG-based indicators to explore insights that might be obtained from them. The initial analysis revealed different cognitive load results from the employed indicators for the same EEG data. In addition, the study implies that the cognitive load results obtained through the used indicators are only partially coherent with the CAD modelling task complexity. Hence, the results imply that the chosen EEG-based indicator matters when measuring and analysing cognitive load in CAD modelling tasks and that its adjustment for CAD context might be needed.

Design and Analysis of a Typical Vertical Pressure Vessel Using ASME Code and FEA Technique

This study aims to address the hazards associated with the design and manufacture of pressure vessels used for storing dangerous liquids, specifically focusing on the increased demand for liquefied petroleum gas (LPG) worldwide. The construction of more LPG facilities necessitates the implementation of safer pressure vessels to mitigate risks such as explosions and leakage. The primary objective of this project is to design a vertical pressure vessel, in accordance with the American Society of Mechanical Engineers (ASME) code, capable of safely storing 10 m3 of pressurised LPG. To ensure the safety of the pressure vessel, the researchers employed Autodesk Inventor Professional 2023 for geometric modelling and utilised Inventor Nastran for finite element analysis (FEA) to investigate displacements, deflections, and von Mises stresses. The vessel is cylindrical in shape and features two elliptical heads, two nozzles, a manway, and four leg supports. The FEA analysis conducted using Autodesk Inventor Nastran enabled the researchers to identify areas where structural modifications were necessary to reduce stress within the vessel. The results revealed an inverse relationship between the displacement and the tank section shell thickness. Additionally, the factor of safety exhibited a linear increase as the shell thickness increased. The researchers carefully considered permissible pressures and determined the required wall thickness to maintain acceptable maximum stresses. The findings indicate that the design of the pressure vessel is safe from failure. Among the components, the manway experiences the highest stresses, followed by the shell, while the heads, nozzles, and leg supports experience lower stresses. The researchers also conducted theoretical calculations for the entire model and ensured that the results fell within acceptable limits, further validating their design approach. The research emphasised the importance of designing pressure vessels in compliance with ASME codes to ensure safety and prevent hazards associated with improper design and manufacturing. The combination of Autodesk Inventor Professional and Inventor Nastran proved to be an effective approach for simulating and evaluating the performance of the pressure vessel. Through the analysis, the researchers found that changes to the pressure vessel structure were necessary to reduce stress. They observed an inverse relationship between displacement and tank section shell thickness, while the factor of safety increased linearly with shell thickness. Stress distribution analysis revealed that the manway and shell experienced the highest stresses, while the heads, nozzles, and leg support exhibited lower stresses. Employing the finite element method, potential stress points within the pressure vessel were identified, enabling necessary modifications to enhance its safety.