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The purpose of this paper is to show a possibility of how new functions can be integrated in parts, created by the powder-bed-based 3D-printing technology. One big advantage of additive manufacturing technologies is the possibility to create function-integrated parts during the manufacturing process. This applies to mechanical functions like movable elements, thermodynamic functions like contour near cooling channels in a part as well as electrical functions like conductive lines and electrical components.

A powder-bed-based 3D-printer is utilized to process polymethyl methacrylate (PMMA) as base material. To enable new functionalities, an automated exhausting mechanism was implemented into the test system. The created cavities can be filled with new components or rather new materials.

Three different approaches are shown in this paper. The first one was the integration of screw nuts to enhance bolted joints compared to threads, directly created in the part. The average tensile strength could be raised from 200 to 430 N/mm. The second approach was the integration of different reinforcement elements like carbon or metallic fibers. Here again a reinforcement of the tensile strength of approximately 27 per cent could be reached. The last approach shows a method to integrate conductive material as well as electrical components in a part to create simple electrical circuits.

The paper demonstrates how to extend an additive powder-bed-based technology with a powder-exhausting mechanism. The possibilities of this technology are illustrated by three examples, integrating mechanical as well as electrical functions in a part.

Defective parts in manufacturing is a serious issue faced by every manufacturer. Even after proper care in design, material selection and manufacturing of product, there exists a defective part. The purpose of this paper is to explore the quality of the manufacturing, and find the use of effective quality tools to reduce the part defect rate in an electrical parts manufacturing unit, thereby, reducing the replaced cost of defective parts.

With the help of quality initiatives, like total quality management (TQM) and Lean Six Sigma (LSS), the firms can produce quality product in each stage of production. The paper focuses on the primary data collected from the XYZ electric manufacturer.

The main finding of this case analysis is that by the effective use of quality tools, the defective part return rate can be reduced, because of which the firm can observe reduction in replaced cost of almost INR24 lakh. In addition, 10A switch part contributes more in replacement cost. Further, it adds to the 35 percent of the overall part rejection.

The study is more focused on particular type of switch product and can extend to other types of products. In addition, the analysis reveals the results of only 88 percent of the defective products.

The study provides results of the improved quality by effective use of quality tools and discusses the different types of defects in the electrical parts manufacturing. Introducing TQM and LSS to manufacturing can reduce the customer return rate to 1,300 parts per million (PPM) and even to 1,000 PPM in future.

The paper discusses the quality issues in the electrical manufacturer. Moreover, the case analysis briefs effective ways to improve the product quality and reduce the rejection rate.

The purpose of this exploratory paper is to analyze how complexity of an artifact affects designing processes of its mechanical, electric, and software sub‐systems.

Based on existing empirical research and frameworks of axiomatic design, product architecture, and product development process, the paper proposes a simple model of functional and structural design to examine how engineers' ways of thinking differ among mechanical, electric and software engineers.

This paper argues that products and artifacts tend to become complex (often with integral architecture) when customers' functional requirements become more demanding and societal/technological constraints become stricter, and that complex mechanical products are often accompanied by electronic control units with complex functions. This implies that designing complex mechanical products often requires intensive coordination among mechanical, electric and software engineers. This, however, is not easy, as engineers' way of thinking is often different among the three areas: mechanical engineers want to complete structural design information first to build prototypes; electrical and software engineers (the latter in particular) request complete functional information first.

In order to solve the above‐mentioned mechanical‐electrical‐software coordination problem, engineers need to share basic design concept of the product in question. Heavy‐weight product managers who infuse the product concept to the project members might be the key to this coordination. Companies may need to make sure that their product development processes are friendly to all of the three groups of engineers.

Although designing complex artifacts has been a popular research theme since H. Simon's seminal work, issues of organizational coordination for developing complex products, with increasing managerial importance, need further research. With an empirical case of the automobile and electronic products, the present paper is unique in that it combines frameworks of product development processes, product architectures, and organizational capabilities.

The purpose of this study is to create an extended equivalent circuit model for a compound DC motor, consisting completely of electrical parameters and quantities.

The dynamic model of the compound DC motor is obtained by establishing the voltage equations for the armature and excitation circuit and the mechanical equation for the mechanical part. The mechanical parameters in the dynamic model are converted into electrical parameters with an electrical circuit proposed for the mechanical part. By combining the armature and excitation circuits with the electrical circuit created for the mechanical part, the extended equivalent circuit model of the compound DC motor is obtained. Because the proposed extended equivalent model is completely an electrical circuit, simulations can be made in the circuit simulation programme. Simulations of the proposed compound DC motor circuit were carried out, and the accuracy of the proposed circuit was verified by performing experimental studies with an existing compound motor.

When comparing speed and current profiles in experiments and simulations, it is seen that compound DC motor can be modelled with the proposed equivalent circuit including completely electrical elements in a simulation programme for the circuits. The results show that the proposed equivalent circuit satisfies the dynamic model of the compound motor.

In DC machine models, armature and excitation circuits are given as an electrical circuit, and mechanical part of the machine is modelled by only mechanical equations. The originality of this study is converting the dynamic model of an electrical machine consisting of electrical and mechanical equations into a completely electrical circuit. With the proposed method, the dynamic model of many motors can be converted into a completely electrical circuit. In this way, motors can be simulated as an electrical circuit in simulation programmes for the circuits, and the dynamic behaviour of motors can be obtained.

This paper presents a method for estimating the macro‐economic cost of a firm‐level information system disruption within a supply chain.

The authors combine field study estimates with a Leontief‐based input‐output model to estimate the macro‐economic costs of a targeted internet outage that disrupts the supply chain.

The authors find that supply chain vulnerability or resiliency to cyber disruptions is not necessarily dependent on the types of technology employed, but rather how the technology is used to enable supply chain processes and the type of attack experienced. The authors find that some supply chains like oil and gas could be significantly impacted by certain cyber disruptions. However, similar to other causes of supply chain disruptions such as labor disputes or natural disasters, the authors find that firms can be very resilient to cyber disruptions.

The validity of the approach is limited by the accuracy of parameters gathered through field studies and the resolution of government economic data.

Managers should examine how information technology is used to enable their supply chain processes and develop capabilities that provide resilience to failures. Lean supply chains that focus on minimizing inventory may be more vulnerable to major information system failures unless they take special steps to build resilience.

This paper provides a new approach to estimating economic vulnerability due to supply chain information failures.

The purpose of this study is to provide means of reflection on the skill acquired during accidents occurring in normal and disorganized situations as well as to draw the consequences, memorize and reuse them in order to avoid them in the future.

We perceive the external and familiar manifestations of the use of electricity such as light, heat and motion. The lack of a direct visual perception of this type of energy often leads to serious consequences caused by either ignored or underestimated risks. The severity of accidents related to electrical risk remains high: nearly 1 in 100 deaths was caused by electricity in 2010. In Algeria, nearly 180 deaths per year are electricity-related; electricity is also the cause of 20 per cent of fires. As the prevention of this risk affects many sectors, apart from power generation and power distribution networks, workers in all types of work areas, from construction to maintenance, are likely to be exposed to electrical hazards.

The results of this study imply that any workplace can face an electrical accident. Therefore, in this work, the authors have attempted to create a memory of risks, based on the feedback of fatal adverse events manifested in a national company, Sonelgaz, in Algeria. Asystematic analysis of these three fatal accidents allows prediction of possible dangerous situations and helps to better plan the objective prevention of such future incidents.

The lack of direct visual perception of this type of energy often leads to serious consequences caused by ignored or underestimated risks. The severity of accidents related to electrical risk remains high: nearly one over 100 deaths are because of electricity in 2010. In Algeria, the authors recorded nearly 180 deaths per year; it is also the cause of 20 per cent of fires. As now, because the prevention of this risk affects many sectors, apart from power generation and power distribution networks, all types of work, from construction to maintenance are likely to expose workers to electrical hazards. This implies that any company can face an electrical accident. Therefore, in this work the authors try to create a memory of risks, based on the feedback of fatal adverse events manifested in the national company Sonelgaz in Algeria.

This paper deals with the collaborative design of electromagnetic devices over the internet network. The design is made by both mechanical and electrical engineers. So, the paper tries to show the importance but also constraints to size such a system using a collaborative optimisation process.

The paper compares two approaches in order to size an electromechanical actuator between mechanical and electrical engineers. In the first one, each profession designs its part, and only common constrained are negotiated. This can result in a design process with many iterations. In the second one, electrical and mechanical engineers built together a common model of the structure and a common list of specifications: this allows a global optimisation that is more efficient.

The main result of the paper is that the second approach in which a global model is built between electrical and mechanical engineers is more efficient.

The originality of the paper is to explore the problems and difficulties of an optimisation of an electromechanical device between engineers of different culture working together over the internet network.

Based on the framework of Krylov subspace-based model order reduction (MOR), compact models of the piezoelectric energy harvester devices can be generated. However, the stability of reduced piezoelectric model often cannot be preserved. In previous research studies, “MOR after Schur,” “Schur after MOR” and “multiphysics structure preserving MOR” methods have proven successful in obtaining stable reduced piezoelectric energy harvester models. Though the stability preservation of “MOR after Schur” and “Schur after MOR” methods has already been mathematically proven, the “multiphysics structure preserving MOR” method was not. This paper aims to provide the missing mathematical proof of “multiphysics structure preserving MOR.”

Piezoelectric energy harvesters can be represented by system of differential-algebraic equations obtained by the finite element method. According to the block structure of its system matrices, “MOR after Schur” and “Schur after MOR” both perform Schur complement transformations either before or after the MOR process. For the “multiphysics structure preserving MOR” method, the original block structure of the system matrices is preserved during MOR. 

This contribution shows that, in comparison to “MOR after Schur” and “Schur after MOR” methods, “multiphysics structure preserving MOR” method performs the Schur complement transformation implicitly, and therefore, stabilizes the reduced piezoelectric model.

The stability preservation of the reduced piezoelectric energy harvester model obtained through “multiphysics structure preserving MOR” method is proven mathematically and further validated by numerical experiments on two different piezoelectric energy harvester devices.

To prevent the coil from burning or getting damaged, it is necessary to estimate the duration of its operation as long as its temperature does not exceed the permissible limit. This paper aims to investigate the effect of switching on the thermal behavior of impregnated and nonimpregnated windings. Also, the safe operating time for each winding is determined.

The power loss of the winding is expressed as a function of the winding specifications. Using homogenization techniques, the equivalent thermal properties for the homogenized winding are calculated and used in a proposed thermal equivalent circuit for winding modeling and analysis. The validity and accuracy of the proposed model are determined by comparing its analysis results and simulation and measurement results.

The results show that copper windings have better thermal behavior and lower temperature compared to aluminum windings. On the other hand, by impregnating or increasing the packing factor of the winding, the thermal behavior is improved. Also, by choosing the right duty cycle for the winding current source, it is possible to prevent the burning or damage of the winding and increase its lifespan. Comparing the measurement results with the analysis results shows that the proposed equivalent circuit has an error of less than 4% in the calculation of the winding center temperature.

In this paper, the effect of temperature on the electrical resistance of the coil is ignored. Also, rectangular wires were not investigated. Research in these topics are considered as future work.

By calculating the thermal time constant of the winding, its safe operation time can be calculated so that its temperature does not exceed the tolerable value (150 °C). The proposed method analyzes both impregnated and nonimpregnated windings with various schemes. It investigates the effects of switching on their thermal behavior. Additionally, it determines the safe operating time for each type of winding.

Metamaterials are artificially tailored complex media with extraordinary properties, not available in nature. Due to their unique performance, they are considered as a crucial component of modern radio-frequency technology, especially in the THz regime. However, their lack of wide spectral bandwidths introduce constraints for realistic applications. The purpose of this paper is to propose piezoelectric micro-electromechanical systems (MEMS) actuators to modify the shape of electric field-driven LC (ELC) resonators. A THz modulation capability is revealed by connecting/disconnecting the associated metal parts.

Piezoelectric MEMS actuators are proposed to provide the desired bandwidth enhancement along with THz modulation. Two setups with different degrees of freedom in altering the behaviour of the novel modulator are investigated. A variety of numerical data, acquired via the finite element method, substantiate the advantageous characteristics of the proposed structures.

The novel devices enable the modification of the structural features of an ELC-based complex medium, unveiling in this manner a significant THz modulation capability along with improved bandwidth tunability. Two discrete cases are presented involving different degrees of freedom to shape the overall performance of the metamaterial modulator.

Development of a THz modulator, which utilises metamaterials as its fundamental component. Incorporation of tunable piezoelectric metamaterials into THz technology allowing increased reconfigurability. Bandwidth enhancement of metamaterial systems and alternative design via multiple controllable gaps enabling more degrees of freedom for design purposes.