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Biological structures have evolved to very efficiently generate, transmit, and withstand mechanical forces. These biological examples have inspired mechanical engineers for centuries and led to the development of critical insights and concepts. However, progress in mechanical engineering also raises new questions about biological structures. The past decades have seen the increasing study of failure of engineered structures due to repetitive loading, and its origin in processes such as materials fatigue. Repetitive loading is also experienced by some neurons, for example in the peripheral nervous system. This perspective, after briefly introducing the engineering concept of mechanical fatigue, aims to discuss the potential effects based on our knowledge of cellular responses to mechanical stresses. A particular focus of our discussion are the effects of mechanical stress on axons and their cytoskeletal structures. Furthermore, we highlight the difficulty of imaging these structures and the promise of new microscopy techniques. The identification of repair mechanisms and paradigms underlying long-term stability is an exciting and emerging topic in biology as well as a potential source of inspiration for engineers. [ABSTRACT FROM AUTHOR]

This paper concerns the identification of current communication technologies and software functionalities from the field of digitalization and Industry 4.0, from the point of view of benefits and applicability for the machine manufacturer. To identify the relevant technologies and functionalities, research was carried out in both the descriptive and statistical literature. As a result, both technologies that are currently the most widely distributed, as well as eleven IT functionalities relevant to mechanical engineers, were identified and described in terms of their application and implementation. Furthermore, a knowledge gap was identified in the area of industry transfer in the field of Industry 4.0/digitalization. [ABSTRACT FROM AUTHOR]

Although a crane is exposed to a wide range of loads, there is a growing need for a lighter, more slender design. As a result, double girder cranes are becoming single girder cranes, aiming to make the steel structure as light as possible. The optimization potential of the classic design as a hollow-box girder is approaching its end. In order to meet today's requirements, a new design was developed, which combines beams with curved panels into a new cross-section to be used as the crane's main girder. Compound cross-sections pose a challenge for the mechanical engineer as there are usually no comparative data available and designing using numerical methods is complex. For this reason, a scaled model was abstracted for which a load determination will be carried out in 2024. This article deals with the finite element calculations for the design of the test specimen. A global numerical analysis was used to determine the buckling load, and several imperfection patterns were investigated. The results revealed that the buckling loads are similar to each other. This finding may lead to the conclusion that the most damaging imperfection pattern has yet to be found, which supports the need for an accompanying series of tests. [ABSTRACT FROM AUTHOR]

Copyright of Ingeniería (0121-750X) is the property of Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Educación en Ingeniería is the property of Asociacion Colombiana de Facultades de Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The coefficient of friction (COF) is an important parameter for mechanical engineers to consider when designing frictional connections. Previous work has shown that a surface microstructuring of the harder friction partner leads to a significant increase in the COF. However, the impact of the changes in the tribological system on the COF are not known in detail. In this study, the tribological influence factors such as the nominal surface pressure, the material pairing, lubrication, and the surface properties of the counterbody are investigated. Microstructuring is applied by turn-milling of an annular contact surface of cylindrical specimens. A torsional test bench is used to measure the torque depending on the displacement of the two specimens, thus enabling the determination of the COF. All tests with the microstructured specimens result in higher COF than the reference test with unstructured samples. The manufacturing process of the counterbody surface, the nominal surface pressure, and the materials in contact have a significant influence on the COF. While lubrication reduces friction in the case of unstructured specimens, the COF does not change significantly for microstructured samples. This proves that the deformative friction component dominates over the adhesive. Microstructuring the harder friction partner increases the transmittable torque in frictional connections and reduces the sensitivity towards possible contamination with lubricants. [ABSTRACT FROM AUTHOR]

Dynamic contact and impact problems are widely applicable. An accurate solution method for these kinds of problems can be used in many fields of mechanical engineering (e.g., cutting metalwork, cogwheel drives, etc.). However, the proper handling of the contact is problematic, as there emerges a substantial amount of nonlinearity in the displacement field. Therefore, a spurious high frequency oscillation is present in the solution. These oscillations must be avoided, as divergence can easily occur in the contact algorithm due to them. In order to eliminate this effect, the applied numerical method must be chosen and set properly. In this study, a comprehensive guide is provided for the appropriate selection of the proper numerical method and its parameters. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) with superior mechanical properties are expected to play a role in the next generation of critical engineering mechanical materials. Crucial advances have been made in CNTs, as it has been reported that the tensile strength of defect-free CNTs and carbon nanotube bundles can approach the theoretical limit. However, the tensile strength of macro carbon nanotube fibers (CNTFs) is far lower than the theoretical level. Although some reviews have summarized the development of such fiber materials, few of them have focused on the controllable preparation and performance optimization of high-strength CNTFs at different scales. Therefore, in this review, we will analyze the characteristics and latest challenges of multiscale CNTFs in preparation and strength optimization. First, the structure and preparation of CNTs are introduced. Then, the preparation methods and tensile strength characteristics of CNTFs at different scales are discussed. Based on the analysis of tensile fracture, we summarize some typical strategies for optimizing tensile performance around defect and tube–tube interaction control. Finally, we introduce some emerging applications for CNTFs in mechanics. This review aims to provide insights and prospects for the controllable preparation of CNTFs with ultra-high tensile strength for emerging cutting-edge applications. [ABSTRACT FROM AUTHOR]

Prestressed anchor cable is widely used in geotechnical engineering to control the displacement or landslide of an unstable slope. However, the traditional cable anchor is made of steel material, which is easy to get rust in a corrosive environment. Basalt fiber-reinforced plastics (BFRP) are a kind of emerging compound material, with a good performance of high strength, low weight, and anticorrosion. Herein, an innovative large-tonnage pressure-type prestressed anchor is made with BFRP. This large-tonnage BFRP anchor cable has seven bunch structures of the "BFRP-connector-strand." In each bunch of the "BFRP-connector-strand," three BFRP tendons and one steel strand are connected inside a steel sleeve connector using the epoxy resin adhesive. The ultimate load-bearing capacity of this BFRP cable anchor can reach 202.38 tonnages. At the ultimate tensioning force condition, the strain of BFRP tendons for this large-tonnage BFRP anchor cable ranges from 1.51% to 1.76%. In the tensioning operation, there is a linear growth relationship between the tensioning force and the strain for this BFRP cable anchor. Once the tensioning force reaches the ultimate strength of this BFRP anchor cable, this cable will present system failure. This situation primarily results from the failure of the "BFRP-connector-strand." The failure modes of this BFRP anchor cable can be classified into three types: the steel strand rupture, the steel connector rupture, and the BFRP tendon rupture. During the tensioning operation, due to the length difference of the BFRP tendons, this large-tonnage BFRP cable anchor presents an end-off-axis effect. It makes the load bearing of the BFRP tendons 5.00~6.60 times larger than that of the no end-off-axis effect. Nevertheless, due to the plastic deformation of the end steel anchor sleeve, the influence of the end-off-axis effect decreases with the increase of applied tensioning force. The load-bearing capacity of this large-tonnage BFRP cable anchor reaches 87.70~91.50% of its theoretical value. [ABSTRACT FROM AUTHOR]

FMEA is a widely used tool for decades and is also used as an industrial standard. However, there are two main drawbacks of this analysis that have been specified from the beginning. The first one is risk prioritization, which is expressed by a risk priority number (RPN). The RPN is a product of three factors with equal weight: severity (S), occurrence (O), and detection (D), which may produce equal risk priority for different combinations of S, O, and D. The second is the uncertainties caused by converting linguistic terms into quantitative data. The essential data used in the FMEA strongly depend on subjective experts' opinions, knowledge, and experience. For decades, various attempts of overcoming these weaknesses have been made, not only by academics but also by industry. The Automotive Industry Action Group (AIAG) and Verband der Automobilindustrie (VDA) have created an FMEA handbook that defines action priority (AP) depending on the combination of severity, occurrence, and detection numbers. This study presents an alternative to risk prioritization in FMEA based on failures of the tasks which analyzed systems perform. The fundamental factors S, O, and D have been redefined in a way to minimize uncertainties. The proposed method has been implemented in the flow control valve and can be easily applied in mechanical engineering applications. [ABSTRACT FROM AUTHOR]

The goal of this paper is to extend the concept of complex-valued fuzzy metric space to complex-valued fuzzy b -metric spaces and to discuss various existence results for fixed points to ensure their existence and uniqueness. To demonstrate the viability of the proposed strategies, a nontrivial example is used. Finally, applications to integral equations and initial value problems in mechanical engineering are discussed to demonstrate the superiority of the obtained results. [ABSTRACT FROM AUTHOR]

The objective was to propose changes in subjects to improve the general knowledge of engineering and maintenance management in the Mechanical Engineering career of the Technical University of Manabi. Two surveys were designed to know how the graduates reflected their knowledge in the area of maintenance engineering and management knowledge as well as the requirements they were expected to have for the industrial sector of the province of Manabí, fundamentally as well as validating these tools through the Kuder-Richard method. Relationship matrices were implemented to know if the current subjects of the mechanical engineer's study plan complied with the requirements requested by the industrial sector. The main results obtained showed that they did not meet the requirements, so two new subjects and their objectives were proposed to solve the deficiencies detected. [ABSTRACT FROM AUTHOR]

Contribution: This article presents an innovative course sequence to integrate Electrical Engineering (EE) Fundamentals into the Mechanical Engineering (ME) Instrumentation and Data Acquisition (DAQ) course and reports students’ experience relevant to the sequence’s intended outcomes of helping students learn and connect EE concepts with ME applications and develop their engineering identities. Background: The ME Department at Seattle University was awarded a National Science Foundation Grant to revolutionize its undergraduate program. This project focuses on doing engineering to foster stronger engineering identities. This course sequence is part of the curriculum change for this project and includes open-ended, real-world labs incorporating both EE and DAQ. Research Questions: 1) Engineering Learning: What evidence is there that students learned EE and DAQ concepts and integrated them with ME? 2) Identity Development: How did the students connect the experience to their evolving identity as engineers? 3) Over-Time Experience: How did students experience the course? Methodology: A mix of quantitative and qualitative data was used: quantitative data (a standardized test) and qualitative data source (mini reflections that students provided over the course sequence) were analyzed to address the research questions that connect the educational design aspects and the intended outcomes. Findings: The new course sequence created an opportunity to do engineering in a rich way and provided fertile ground for developing engineering identities. Students understood and retained EE and DAQ concepts at a level equal to when the material was taught via separate courses. [ABSTRACT FROM AUTHOR]

An elastic wave in a physical beam naturally possesses many wave modes, such as flexural, longitudinal, and torsional. Therefore, suppression of all possible vibration modes has been rarely achieved in beam-shaped periodic systems, especially at low frequencies. Here we present a low-frequency complete bandgap mechanism by overlapping the flexural bandgap with the longitudinal-torsional bandgap. To strengthen the general framework, we enforce an extra degree of freedom (rotational and torsional-spring) on the spring-mass system for the flexural and coupled (longitudinal-torsional) modes. The low rotational stiffness provides a low flexural bandgap, whereas the torsional stiffness yields a coupled-mode bandgap. To meet these prerequisites in physical modeling, a chiral trabeated metabeam is conceived, which allows all wave modes to be suppressed by a complete bandgap. Apart from single-mode mitigation, our work provides a route to implementing a low-frequency complete bandgap in a periodic fashion, potentially enabling the use of chirality in elastic structures. Engineering the mechanical response of metamaterials allows control of mechanical modes, with potential application to vibrational isolation. Here, a general framework for achieving a complete band-gap by combining orthogonal flexural and longitudinal-torsional band-gaps is demonstrated analytically and experimentally. [ABSTRACT FROM AUTHOR]

We offer a neural network-based control method to control the vibration of the engineering mechanical arm and the trajectory in order to solve the problem of large errors in tracking the path when the engineering mechanical arm is unstable and under the influence of the outside world. A mechanical arm network is used to perform tasks related to learning the unknown dynamic properties of a engineering mechanical arms keyboard without the need for prior learning. Given the dynamic equations of the engineering mechanical arm, the dynamic properties of the mechanical arm were studied using a positive feedback network. The adaptive neural network management system was developed, and the stability and integrity of the closed-loop system were proved by Lyapunov's function. Engineering mechanical arm motion trajectory control errors were modeled and validated in the Matlab/Simulink environment. The simulation results show that the management of the adaptive neural network is able to better control the desired path of the engineering mechanical arm in the presence of external interference, and the fluctuation range of input torque is small. The PID control has a large error in the expected trajectory tracking of the engineering mechanical arm, the fluctuation range of the input torque is as high as 20, and the jitter phenomenon is more serious. The use of detailed comparisons and adaptive neural network monitoring can perform well in manipulating the trajectory of the engineering mechanical arm. The engineering mechanical arm uses an adaptive neural network control method, in which the control precision of engineering mechanical arm motion trajectory can be improved and the out-of-control phenomenon of mechanical arm motion can be reduced. [ABSTRACT FROM AUTHOR]

The mathematical modelling is an inseparable part of mechanical engineers’ activities. It is applied in design, optimization, verifying, as well as modifying of products. The approach of creating virtual models and their analyzing without having real products is applied in several domains. A mathematical model is given by equations of motion. The main objective of this work is to present the way how a mathematical model of a car powertrain operation is derived and applied in practical applications. A semi-trailer tractor with a standard powertrain was chosen as a reference car. The derived equations of motion are written in a matrix form and subsequently they are solved by means of a technical programming language Matlab. Parameters of the solved tractor mechanical system come from the real data and they are supplemented by the empirical data. [ABSTRACT FROM AUTHOR]

At conferences or meetings, West Point faculty are often asked, “What’s it like to teach at West Point?” Previously, we reported on this question within the context of the cadet’s West Point experience and how STEM courses and opportunities are integrated. Now we turn our focus to the West Point faculty and their unique position of both educating cadets in a traditional sense and helping with the cadets’ character development. In this article, we discuss who the West Point faculty are; what is expected of each faculty member; and how faculty members within chemistry, physics, mechanical engineering, and civil engineering educate and develop future leaders of character for the U.S. Army. [ABSTRACT FROM AUTHOR]

Teaching, in a pandemic, has been modified and distance processes have taken an important place. This work describes what strategies were generated to achieve learning with appropriate results, under these conditions. Various experiences and a group of proposals are reported for students of the mechanical engineering career, of two elective subjects (Surface Engineering, Selected Topics of Materials), online teaching. The resources used, the forms of evaluation used are described and evidence of the learning achieved is presented. With this, a growing participation of the students and an adequate level of learning were achieved. The purpose of this work is to contribute to the teaching work of teachers in the teaching of Materials, online education, sharing the alternatives described and used in these two subjects, which, to some extent, can be transferred to others and make a reflection about its strengths and limitations. [ABSTRACT FROM AUTHOR]

The design of a roll-type electrochemical membrane device, which makes it possible, in contrast to the known analogues, to increase the membrane area per unit volume of the device and to improve the quality and efficiency of separation of solutions of chemical, mechanical engineering, and agro-processing industries, is proposed. A method is proposed for calculating the parameters of the roll-type electrochemical membrane device, such as the total cooling and separation areas and individual and total area of cathode- and anode-adjoined membranes. [ABSTRACT FROM AUTHOR]

An improved design of a tubular electrochemical membrane apparatus where three cylindrical mesh agitators are used in the solution separation chamber for intensive mixing of the solution and threaded, instead of flanged, connections are used for pipeline fittings is proposed for effective separation of solutions of chemical, mechanical engineering, and agro-processing industries. A method is proposed for calculating the technological parameters of the tubular electrochemical apparatus, such as the total volume of the solution to be separated, the areas of the anode- and cathode-adjoined membranes and their total area, etc. [ABSTRACT FROM AUTHOR]

In order to strengthen the thermal conductivity of green cutting fluid and the influence of nano-cutting fluid from new cutting and forming processes on heat transfer performance of mechanical engineering, a research method was proposed based on the influence of nano-cutting fluid from new cutting and forming processes on heat transfer performance of mechanical engineering. The dispersion stability, thermal conductivity, and viscosity characteristics of the nanofluid were studied, and the effects of acidification treatment time, type and concentration of carbon tube particles, surfactants, and testing conditions on the above properties were analyzed. It was found that the filling rate of T321 was about 25% when CNTs were filled, and the optimal compounding ratio of the two surfactants, sodium dodecyl benzenesulfonic acid (SDBS) and Tween-80 (TW-80), for the preparation of stable dispersed nanofluids was 3 ∶ 7. The optimum ratio of compound active agent to carbon tube is 5 ∶ 1. When CNTs were acidified for about 9 h and dispersed in sufficient and stable condition, the thermal conductivity of the base liquid was increased by 110% by the composite, and the shape factor of CNTs had the most significant effect on the thermal conductivity. It was found that the composite nanofluids had higher thermal conductivity and lower viscosity than the nanofluids prepared by ordinary CNTs. This was due to the fact that surfaces of CNTs were chemically modified during the opening and internal filling process, so that the composite had better dispersion stability in the base fluid. [ABSTRACT FROM AUTHOR]

Featured Application: The proposed approach in this paper can help designers to generate novel design structure solutions from first principles in conceptual design (especially in the field of mechanical engineering). It could be regarded as a supplement to existing functional design approaches. (1) Background: Functional design is an activity that is part of conceptual design; it aims to clarify customer needs and develop the functional architecture and solution concepts for a product or system under development. The existing functional design approaches mainly focus on assisting designers in searching for design solutions to desired functions, which rely too much on established design knowledge. This type of approach is usually characterized by the relevant design analogy, especially case analogy, or structure analogy. However, this cannot help to generate new design solutions if there is little established design knowledge. (2) Methods: To overcome this limitation, working principle and property are designated as intermediate transformation variables. The corresponding mapping relationships, from function to working principle, and from working principle to property, are comprehensively discussed. Then, an extended functional design approach is proposed, which is characterized by the function (F)–working principle (WP)–property (P)–structure (S) mapping process. The conceptual design of a self-adaptive luggage transfer device is taken as an example to illustrate the proposed approach. (3) Conclusions: Based on the working principle and the desired property, how to generate a possible structure solution according to an expected function is clarified explicitly. The proposed approach could be regarded as a complement to the existing functional design approach. [ABSTRACT FROM AUTHOR]

A substructure hybrid test is an effective approach to reproduce the seismic behavior of engineering structures. The structure is partitioned into several substructures; those with complex behavior are analyzed experimentally, whereas the others are analyzed numerically, combining the merits of physical experiments and numerical simulations. Previous studies often loaded physical substructures in two or three translational directions. Simultaneous rotational loading in three Cartesian axes is difficult because the load testing device has to be configured spatially, resulting in control problems due to strong coupling. Special expertise in mechanical engineering is necessary to solve this problem. To this end, this study proposes an integrated load testing device suitable for physical loading in all six degrees-of-freedom simultaneously. The device is based on a Stewart platform and can provide a large axial force required by most gravity-bearing components. It also has a large inherent stiffness necessary to obtain the force-displacement curve from damage through complete failure. This paper describes the force-displacement mixed control based on the Stewart configuration, which is necessary for testing engineering structures. Control software is developed and interfaced with the mid-ware OpenFresco to coordinate the numerical substructure. A hybrid test is conducted using a small-scale, electronic-driven load testing device. The test ran smoothly without any malfunctions, demonstrating the excellent performance of the testing system. [ABSTRACT FROM AUTHOR]

Enhancing the stability and durability of metal-organic frameworks (MOFs) is vital for practical applications because many promising MOF materials suffer from phase transitions and/or structural decompositions with humidity being a particularly damaging condition. In mechanical engineering, the frame of buildings and furniture can be stabilized significantly by installing a truss beam. Employing the same principle, we functionalized the organic component of MOF-5 to contain a carbazole moiety that can act as a molecular truss beam by reaching across the corner and forming a stable π–π interaction with a phenyl group on the edge position of the MOF-skeleton. This structural support enhanced the stability of the MOF substantially, allowing the designed MOF to maintain compositional integrity under steam conditions at 90 °C for ~5 days. The unmodified MOF-5 shows clear signs of structural collapse after ~1 h. [ABSTRACT FROM AUTHOR]

Thin walled cold formed structures were, and still are, very popular structural elements used in mechanical engineering. Modern technology and the progress in materials engineering allow to fabricate various shapes of thin walled cold formed components. Therefore, combinations between technology possibilities, material properties, loads and engineering requirements are wide and unlimited for thin walled components. The aim of this paper is to perform an experimental study of cold formed C-channel steel beams under four-points bending loads based on the global and the local buckling phenomena. A test rig was developed with a specially designed support system to subject thin-walled steel beams to a four-point bending load, where the support and loads were applied to the shear center of the open section steel beam. It is shown that it is not possible to completely eliminate the torque load on a thin-walled beam with an open section where load and support are applied in the shear center because investigated beams weren't ideal made. Thin walled open section beams are very sensitive for boundary conditions and geometrical accuracy. The force of gravity is also working. The presented research methodology can be improved and do test with other open section thin walled beams. [ABSTRACT FROM AUTHOR]

This article reports on a qualitative multi-case study exploring the challenges mechanical engineering students experience during work placement. The study collected data from 34 purposively selected mechanical engineering students. It found that constraining learning environments, ineffective industry mentors, low quality work affordances and negative student characteristics can compromise students' work placement learning outcomes. It suggests that the coupling of ineffective mentors and constraining learning environments tends to be associated with low quality work affordances. Industry mentors were considered ineffective if they could not perform the dual role of work supervisors and teachers. It further suggests that some student attributes can also compromise work placement learning outcomes. It found that students who are not proactive or assertive often experience low quality work affordances. To remedy these shortcomings, universities should provide pre-placement training for students and industry mentors in the form of a seminar for industry mentors and simulated work placement for students. [ABSTRACT FROM AUTHOR]

The mechanical indices used to describe the anisotropy of layered rock mass are numerous and difficult to be measured. Take the medium - thick horizontal layered limestone rock mass as an example, rock mechanical tests, engineering geological survey, field tests, numerical back-analysis were done to obtain transverse isotropic deformation parameters and strength indices. Normal and transverse moduli of elasticity of rock mass could be preliminarily confirmed by rock uniaxial compression tests, RQD, and empirical formula. Then vertical compression testing of layered rock mass, vertical and horizontal plate bearing tests, and numerical back-analysis were conducted to determine the other deformation parameters. These parameters include normal and transverse moduli of elasticity, normal and transverse Poisson's ratio, and shear modulus of the rock mass. The cohesion and internal friction angle of the rock mass were then confirmed by direct shear and shear testing. Test results of bidirectional elasticity modulus showed the obvious anisotropy of the layered rock mass. Engineering application indicated that vault settlement was the main deformation mode of the horizontally layered surrounding rock. This differed from the homogeneous rock. Rock falling and delamination readily occurred in the arch of the tunnel. [ABSTRACT FROM AUTHOR]

Precision machining of automotive industrial parts is a highlighted topic in mechanical engineering due to the increased need for efficient and high-quality machining processes. This study is aimed to contribute to the field of surface topography evaluation by analyzing tribology-related topography parameters parallelly and finding connections between them. Hard machining experiments were carried out for the widely applied case-hardened material 16MnCr5 and the 3D topography of the machined surfaces was measured and analyzed. Based on a comprehensive design of experiments cubic response functions were determined for the analyzed parameters and the coefficients of determination were calculated. It was found that the cubic response function is reliable for predicting the topography parameter values and there are strong relationships between counterpart parameters under certain circumstances The findings could help clarify the roles of the analyzed parameters in some tribological properties within the analyzed cutting circumstances. [ABSTRACT FROM AUTHOR]

Industrial equipment is a dynamic system and has deformations not only during installation but also during operation. Under the influence of variable load and displacement of the center of gravity, the soil under the foundation settles unevenly, and accordingly, the equipment deforms unevenly, which is a threat to the equipment, the greater the load corresponds to more subsidence. Separation of partial deformations from full is important for determining the elements of straightening equipment for its uninterrupted and trouble-free operation. The presence of significant total deformation does not affect the performance of the equipment. The most critical deformations are partial deformations. Absolute vertical deformations are calculated as the difference in sediment between adjacent sediment marks, which are fixed on the equipment in the same measurement cycle. Comparing the values of deformations with the allowable technical conditions, decide on the need for straightening and adjustment of equipment. The accuracy of installation is characterized by a tolerance of 0.1÷0.5 mm on the relative position of the equipment, which is conjugate mounted at a distance of several tens or hundreds of meters. For installation of the equipment with such accuracy carry out special geodetic works with use of methods and technical means of measurements specially developed for this purpose in geodesy, metrology and mechanical engineering. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the scientific outputs and co-authorship patterns of Azarbaijan Shahid Madani University in the fields of electrical, civil, and mechanical engineering, based on Web of Science (2000-2019). The paper relied on both quantitative and scientometric methods. 1870 and 291 records were retrieved respectively for "Azarbaijan Shahid Madani University" and "the fields of electrical, civil, and mechanical engineering". The questions and assumptions were answered through descriptive and inferential statistics. VOSviewer and SPSS were used respectively for mapping and testing assumptions. The findings showed that the total scientific outputs of electrical engineering in the world, indexed by the Web of Science (2000-2019) were 2,973,902, of which 44,768 records (1.6%) belonged to Iran (rank 16). During the same period, the total civil engineering records was 395,649, of which 11,876 records (3%) belong to Iran (rank 10). In addition, the total scientific outputs of mechanical engineering were 941,586, of which 25,263 records (2.7%) belonged to Iran (rank 12). The findings showed that in Iran Azarbaijan Shahid Madani University in electrical engineering is ranked 36th (2000-2019). The findings showed that Ajami with 43 (17%), Hoveidae with 5 (23%), Gharraei and Mohammad pourfard, each with 10 records (17%), were the top authors in the fields of electrical, civil, and mechanical engineering (2000- 2019), respectively. Also, Ajami with 43 (1000 citations), Najafi with 42 (564 citations), Banaei with 41 records (473 citations), and Oskuee with 16 records (305 citations) have high co-authorship densities (37, 31, 22, and 29, respectively). Moreover, there was no meaningful difference between men and women in electrical, civil, and mechanical engineering in scientific outputs (Sig=0.0927). Furthermore, there was a significant difference in scientific outputs among electrical, civil, and mechanical engineering researchers in departments and university ranks. [ABSTRACT FROM AUTHOR]

This paper empirically analyzes the incidence of productive diversification on regional performance in Argentina between 2008 and 2018. Assuming that spillovers between productive activities requires proximity in the knowledge base, a distinction is made between related and unrelated productive diversification, which are estimated using entropy indicators. Econometric estimations are performed to explain the dynamics of employment and wages (as proxy for productivity) by the levels of related and unrelated regional diversification. Findings suggest that related diversification has a positive impact on employment and wage dynamics at the regional level, while unrelated diversification contributes to maintaining regional employment during macroeconomic contractions. No empirical evidence is found supporting that general purpose technology (such as mechanical engineering and ICTs) enhances the effects of related diversification on regional performance. It is observed, however, that the software sector enables the presence of externalities between technologically distant activities. [ABSTRACT FROM AUTHOR]

We apply a functional data approach for mixture model-based multivariate innovation clustering to identify different regional innovation portfolios in Europe, considering patterns of specialization among innovation types. We combine patent registration data and other innovation and economic data across 225 regions, 13 years, and eight patent classes. The approach allows us to form several regional clusters according to their specific innovation types and captures spatio-temporal dynamics too subtle for most other clustering methods. Consistent with the literature on innovation systems, our analysis supports the value of regionalized clusters that can benefit from flexible policy support to strengthen regions as well as innovation in a systematic context, adding technology specificity as a new criterion to consider. The regional innovation cluster solutions for IPC classes for 'fixed constructions' and 'mechanical engineering' are highly comparable but relatively less comparable for 'chemistry and metallurgy'. The clusters for innovations in 'physics' and 'chemistry and metallurgy' are similar; innovations in 'electricity' and 'physics' show similar temporal dynamics. For all other innovation types, the regional clustering is different. By taking regional profiles, strengths, and developments into account, options for improved efficiency of location-based regional innovation policy to promote tailored and efficient innovation-promoting programs can be derived. [ABSTRACT FROM AUTHOR]

Design of Mechanism is a standard subject in Mechatronics and Mechanical Engineering majors. Different methods and tools are used by lecturers to teach the subject. In this work, we investigate the impact on the competencies development by implementing a project-based learning methodology in a mechanism course. For this, we analyze the performance of students from two different groups. The first group is taught in a traditional fashion developing a final project just related to the discipline, and the second group is taught in a multidisciplinary context where the final goal is to develop a complex project where the mechanisms subject is one complementary subject with the others. The development of engineering competencies, declared for this course, is presented for both groups through the evaluation of different aspects; also, a survey of satisfaction from the students of both groups is presented. Overall, the results show that the multidisciplinary project-based learning method, having a nonacademic training partner as sponsor and solving a real nonacademic project, improves the development of competencies related to practical applications and increases the motivation and appreciation of the student towards the mechanism learning discipline. [ABSTRACT FROM AUTHOR]

In December 1921, Frank B. and Lillian Moller Gilbreth held a presentation entitled "Process Charts" at the Annual Meeting of The American Society of Mechanical Engineers. They presented a diagrammatic notation for depicting work processes. This was the reason for initiating a call for papers for a special edition of the EMISA Journal. The aim of this issue is to reflect on the history of graphical business process modelling as well as on current and future challenges. In this editorial, we will shortly introduce the ideas behind the Process Charts method. We realize that some ideas discussed 100 years ago still remain highly relevant while modern work environment raises issues that would be unthinkable a century ago. [ABSTRACT FROM AUTHOR]

Electrospun nanofibers have promising properties and serve an important role in various applications ranging from biomedical engineering to mechanical engineering. Although electrospun nanofibers are not used worldwide, the limited research conducted thus far provides a rudimentary understanding of nanofibers and explores the potential areas that have attracted attention for commercialization. However, the lack of a comprehensive understanding of the properties of nanofibers in various applications severely limits their functionality. This review provides clear insights into modifying the morphology of nanofibers by adjusting various parameters to meet specific application requirements. Various applications, including membrane distillation, reinforcement, and self‐healing, and the corresponding desired properties are discussed in detail. Approaches for enhancing the application‐specific properties of electrospun nanofibers are also discussed. This discussion provides significant guidance for the design of novel electrospun composites with excellent properties. Finally, the challenges in research and the opportunities for future development are presented. [ABSTRACT FROM AUTHOR]

Virtual assembly technology is of great significance to training of mechanical engineers. However, existing force rendering models for virtual assembly are not accurate enough with less consideration of geometrical properties of the parts, which may lead to unpractical perceptions during assembly. This paper presents a novel force rendering model for virtual assembly, which takes into account parts' geometrical properties according to the new generation of geometrical product specification (GPS). More specifically, skin model shapes of parts for force rendering are constructed and then the contact between the mating surfaces is analyzed. Based on which, the axial frictional and radial contact resistances are calculated and rendered. To verify the proposed model, two comparative case studies are designed using a shaft-bushing assembly as the example. The results have shown that with the proposed approach, the rendered assembly force is more realistic and can reflect different tolerances more precisely. [ABSTRACT FROM AUTHOR]

With Industry 4.0 and another round of scientific and technological reform and development, industrial reform and development, the latest economic development, and the escalating complexity of the upcoming problems faced by human beings all over the world, there is an urgent need for cross-compounding between disciplines and disciplines, resulting in emerging engineering majors. In response to these situations, the article analyzes the characteristics, necessity, and main problems faced by the construction and talent cultivation of emerging engineering majors with multidisciplinary cross-composite and discusses the new initiatives of building emerging engineering majors with multidisciplinary cross-composite and innovative talent cultivation to encourage the cultivation of brave exploration and innovation, cultivate innovative talents with unique insights, and promote innovation and breakthroughs in economic, social, and scientific and technological development needs. Finally, the article takes mechanical and electronic engineering as an example to explore how the crossover and integration between several important aspects of the construction of emerging engineering majors are effectively carried out in order to provide certain reference and reference for the construction of related emerging engineering disciplines and majors. [ABSTRACT FROM AUTHOR]

The objective of this article is to evaluate the effect that virtual teaching learning generates in the evaluation of teaching performance, from the perspective of the students, of the professional mechanical engineering school. During the development of the research, it has been determined that the planning, communication and overall performance factors of the teaching performance have experienced a positive variation of 63.64%, increasing by 3.8%, when moving from the face-to-face environment to the virtual teaching-learning environment. While the didactic strategies, organization and subject mastery factors have experienced a positive variation of 59.09%, this increase represents 1.92%. Although a positive effect has been generated on teacher performance, it has been determined that, of the 6 factors, it is the Communication factor which has presented the greatest negative variation, being of the total of 22 teachers, 11 who have decreased their qualification. [ABSTRACT FROM AUTHOR]

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The "target value" theory is a concept promoted in the field of mechanical engineering that can bring important benefits for the correct calibration of product quality that is perceived much better if the 6σ deviation and X deviation are minimized for a parameter value given by its target value. Through this work we aim to perform an exhaustive analysis and concrete experiments of this concept with the goal of achieving the Industrial Excellency's targets. For the case studies concrete measures and specifications are suggested. The viewpoint approached in this paper brings an extra value in orienting the technological processes and equipments with a view to achieving the products' quality and competitiveness. [ABSTRACT FROM AUTHOR]

Geometry, electrostatics, and single-electron tunneling contribute to the nonlinearity in the quantum dot embedded nanomechanical resonator, while "Duffing term" is a kind of mathematics describing the third-order nonlinearity of the system as a whole. We study theoretically the influence of a variation of a mathematical parameter Fuffing term on the actual physical effect. The position probability distribution, the average current, and the displacement fluctuation spectrum with the different Duffing parameter and electromechanical coupling are obtained through numerically calculating the Fokker Planck equation. The mechanical bistability has been described by these quantities under different electromechanical coupling and Duffing parameters. We conclude that the nonlinearities of the nanotube resonator contribute to the mechanical bistability, which induces the asymmetry of the position probability distribution, compresses the current, and softens or stiffens the mechanical resonance frequency as the same as the electromechanical coupling to use it in mechanical engineering. [ABSTRACT FROM AUTHOR]