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The aim of this paper is to propose a design procedure based on the impedance boundary condition in order to simplify the design of inductors for domestic induction heating systems.

An electromagnetic description of the inductor system is performed to substitute the effects of a component, named system load, for a mathematical condition, the so‐called impedance boundary condition. This is suitable to be used in electromagnetic systems involving high conductive materials at medium frequencies, as it occurs in an induction heating system. Applying this approach, a simplified electrical model arises from the general system.

A considerable reduction in the efforts devoted to design a coil for induction heating purposes is achieved, because the solution considering the variation of three physical parameters are projected to a one‐dimensional space only depending on a single parameter named corrected penetration depth. This proposal assesses the working conditions of standard induction systems.

This work is performed to achieve a better understanding of the fundamentals involved in the electromagnetic modeling of an induction heating system. The main goal is the definition of a better coil design process because it is probably the most time‐consuming task in the construction of a complete induction system.

In this paper, the so‐called corrected penetration depth is defined. This single parameter allows explaining the influence of the physical parameter of the inductor load and the excitation frequency in the equivalent of the complete inductor system. The numerical results carried out considering the corrected penetration depth instead of the physical load properties have been validated experimentally.

Polyamide 12 (PA12) properties meet specific requirements for various applications in the automotive and aerospace industries. Bulk specimens made of PA12 and processed via the additive manufacturing technique such as selective laser sintering (SLS) present a layered structure. In case of structural applications, the fatigue performance of SLS PA12 parts is of vital importance and fatigue response studies in these type of materials are still scarce. Therefore, the purpose of this paper is to analyse the effect of the applied load orientation on the fatigue crack propagation behaviour of the layered structure of SLS PA12.

With the aim of understanding the effect of the applied load with respect to the layer orientation on the fatigue crack growth of SLS PA12, fatigue crack growth tests were carried out at two orientations. The specimens called PARA were orientated in such a way that the applied force direction belongs to the layer plane while in the group called PERP, the tensile force direction is coincident with the build direction, that is, perpendicular to the slice. Besides, special attention has been paid to the analysis of the fracture surfaces of the specimens, linking the micromechanisms of failure with the microstructure of the material.

The SLS PA12 specimens tested with the load applied parallel to the layered structure show a little better fatigue response than those tested at perpendicular orientation. The fracture surfaces of the specimens tested at perpendicular orientation are slightly smoother than those tested at parallel orientation. Crazes are the main micromechanism of failure with a crater size of 50 microns, which coincide with the spherulite size. This indicates that the void nucleation of the crazes takes places between lamellae inside the spherulites, and consequently, the craze growth and rupture occurs mainly in a transspherulitic mode.

PA12 parts manufactured via SLS are becoming more valuable in structural elements in the automative and aeronatical fields. In such applications, fatigue performance is vital for design. Fatigue studies are scarce in literature and even more when dealing with fatigue crack growth behaviour. The value of this work is the analysis of the fatigue crack growth response of these materials taking into account the anisotropic microstructure and to get a better understanding, this behaviour is explained taking into account the micromechanisms of failure and the microstructure of the material.

A summary of the economic impact resulting from the celebration of a sporting mega-event in the city of Cali, Colombia, is carried out in this article.

The impacts are estimated by means of the systematic effects produced by the activities of investment/expenditure of the identified agents and the consequent multiplying effects captured from an input-output model.

The World Games represented a new income flow to the city of Cali of $101.036 million pesos (≡US$53.4 mill.) and 9.598 jobs were created (≡7,711 full-time jobs). Additionally, 2,174 foreign tourists and 11,250 national tourists were attracted to the city.

The article contributes with innovative aspects methodologically speaking, useful for future studies of economic impact in cities with low tourism located in developing countries.

This chapter's objective is to analyze, with a long-term perspective, the formation of an entrepreneurial culture in Mexico's Midwest, specifically in the state of Jalisco, in terms of the geographical environment, the culture in general, and the local economic institutions that, when viewed interconnectedly, will globally impact the practices, representations, and imaginaries of persons who at a given time have made the decision to undertake profitable economic activities – individual and collective entrepreneurs, in other words. To this end, we have divided the text into two sections. In the first, we conceptually review what we understand as entrepreneurial culture; in principle, we deconstruct its terms and then conjugate them from a social science perspective. We also emphasize the importance of studying the milieu as a scenario of action with different arenas, where a variety of agents have been involved. In the second part, without sidelining conceptual analysis, we present concrete empirical evidence of the role played by culture and local economic institutions that shape entrepreneurial culture in Midwestern Mexico over time, specifically in Jalisco. The text ends with some final considerations.

Taking as reference a sample of around a hundred biographical materials on entrepreneurs in Mexico and Colombia, the purpose of this chapter is dual. Both to show the relevance and varied modalities that the biographical approach has enjoyed in business history research since the 1990s, and to display the intrinsic potential this modality of scholarship entails for entrepreneurship endeavors. In particular, it discusses the prospects to incorporate this body of empirical works into the large Latin American audience attending undergraduate, graduate and executive education programs in business, economic history and related fields. The chapter is organized into three sections. The first two are devoted to illustrate relevant patterns in the entrepreneurial trajectory of individuals and entrepreneurial families studied in each of the two countries under consideration. The last section identifies some conceptual issues that may impact current debates on Latin American business development as exemplified in recent business and economic history journal venues and scholarly conferences.

The purpose of this paper is to analyze a new structural design applied in industrial frames using two type of steels (S275 and fire resistant (FR)) with different mechanical resistance against fire. To do it, the authors have taken into account variables such as intrinsic metallic design, span length, intumescent paint thickness, and fire time exposure, which offers information about new scenarios of design in industry.

The key methodology followed has taken into account a modeling program that uses the following variables: 25 and 35 m of span, 45 and 60 fire exposure times, and seven different intumescent paint thickness. An optimum structural design has been evaluated by discretization of each scenario with the particular type of steel, S275 and FR. The obtained approach could be a good guideline for future designs.

The results and analysis have shown a very good and valid idea of a new structural typology using optimum intumescent paint thickness into the final design of the industrial frame considering that it has two different types of steel. It is in realty a handicap since usually mechanical engineers employ structural steel without paying attention to this new feature.

Cheaper structural designs could be obtained using the two different types of steel considering the proper positioning into the full building.

The validity of design of two types of steel plus intumescent paint in building construction has been shown, and this study will encourage designers to use it, in particular in buildings with high fire risk.

Induction heating processes need to adapt to complex geometries or variable processes that require a high degree of flexibility in the induction heating setup. This is usually done using complex inductors or adaptable resonant tanks, which leads to costly and constrained implementations. This paper aims to propose a multi-level, versatile power supply able to adapt the output to the required induction heating process.

This paper proposes a versatile multilevel topology able to generate versatile output waveforms. The methodology followed includes simulation of the proposed architecture, design of the power electronics, control and magnetic elements and laboratory tests after building a 10-level prototype.

The proposed converter has been designed and tested using an experimental prototype. The designed generator is able to operate at 1 kVpp and 100 A at 250 kHz, proving the feasibility of the proposed approach.

The proposed converter enables versatile waveform generation, enabling advanced tests and processes on induction heating system. The proposed system allows for multifrequency generation using a single inductor and converter, or advanced tests for inductive and capacitive components used on induction heating systems. Unlike previous multifrequency proposals, the proposed generator enables a significantly improved versatility in terms of operational frequency and amplitude in a single converter.