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For repairing turbine blades or die and mold forms, additive manufacturing processes are commonly used to build-up new material to damaged sections. Afterwards, a subsequent re-contouring process such as 5-axis ball end milling is required to remove the excess material restoring the often complex original geometries. The process design of the re-contouring operation has to be done virtually, because the individuality of the repair cases prevents actual running-in processes. Hard-to-cut materials e.g. titanium or nickel alloys, parts prone to vibration and long tool holders complicate the repair even further. Thus, a fast and flexible material removal simulation is needed. The simulation has to predict suitable processes focusing shape deviations under consideration of process stability for arbitrary complex engagement conditions. In this paper, a dynamic multi-dexel based material removal simulation is presented, which is able to predict high-resolution surface topography and stable parameters for arbitrary processes such as 5-axis ball end milling. In contrast to other works, the simulation is able to simulate an unstable process using discrete cutting edges in real-time. © 2020, The Author(s).

For repairing turbine blades or die and mold forms, additive manufacturing processes are commonly used to build-up new material to damaged sections. Afterwards, a subsequent re-contouring process such as 5-axis ball end milling is required to remove the excess material restoring the often complex original geometries. The process design of the re-contouring operation has to be done virtually, because the individuality of the repair cases prevents actual running-in processes. Hard-to-cut materials e.g. titanium or nickel alloys, parts prone to vibration and long tool holders complicate the repair even further. Thus, a fast and flexible material removal simulation is needed. The simulation has to predict suitable processes focusing shape deviations under consideration of process stability for arbitrary complex engagement conditions. In this paper, a dynamic multi-dexel based material removal simulation is presented, which is able to predict high-resolution surface topography and stable parameters for arbitrary processes such as 5-axis ball end milling. In contrast to other works, the simulation is able to simulate an unstable process using discrete cutting edges in real-time. © 2020, The Author(s).

[EN] One of the ways to increase students' motivation and participation in the classroom is to propose a wide variety of resources and activities so that the teaching materials to be used are suitable for the largest possible number of students. Today's students have grown up in an environment where technological supports are part of their daily lives. For this reason, this work proposes the incorporation of Information and Communication Technologies (TIC) together with other quality materials as a medium for information on teaching content. The main objective of this methodology is that the proposed tools allow learning the subject in a more attractive and enjoyable way, as well as promoting communication between students and teachers. This model has been implemented within the Mathematics I classes of the Degree in Industrial Electronic and Automatic Engineering, both in theory and in classroom and computer practices., [ES] Una de las maneras de aumentar la motivación y la participación en las aulas por parte de los alumnos es el planteamiento de una gran variedad de recursos y actividades de forma que los materiales docentes a trabajar se adecuen al mayor número de alumnos posible. Los alumnos de hoy en día han crecido en un ámbito donde los soportes tecnológicos forman parte de su vida cotidiana. Por ello, en este trabajo se propone la incorporación de las Tecnologías de la Información y la Comunicación (TIC), junto con otros materiales de calidad obtenidos en la web, como soporte de información de los contenidos docentes. El objetivo principal es que las herramientas propuestas permitan profundizar en la materia de forma más atractiva y amena, así como fomentar la comunicación entre alumnos y profesores. Este modelo se ha implementado dentro de las clases de Matemáticas I del Grado en Ingeniería Electrónica Industrial y Automática, tanto en la teoría como en las prácticas de aula e informáticas.

[EN] One of the ways to increase students' motivation and participation in the classroom is to propose a wide variety of resources and activities so that the teaching materials to be used are suitable for the largest possible number of students. Today's students have grown up in an environment where technological supports are part of their daily lives. For this reason, this work proposes the incorporation of Information and Communication Technologies (TIC) together with other quality materials as a medium for information on teaching content. The main objective of this methodology is that the proposed tools allow learning the subject in a more attractive and enjoyable way, as well as promoting communication between students and teachers. This model has been implemented within the Mathematics I classes of the Degree in Industrial Electronic and Automatic Engineering, both in theory and in classroom and computer practices., [ES] Una de las maneras de aumentar la motivación y la participación en las aulas por parte de los alumnos es el planteamiento de una gran variedad de recursos y actividades de forma que los materiales docentes a trabajar se adecuen al mayor número de alumnos posible. Los alumnos de hoy en día han crecido en un ámbito donde los soportes tecnológicos forman parte de su vida cotidiana. Por ello, en este trabajo se propone la incorporación de las Tecnologías de la Información y la Comunicación (TIC), junto con otros materiales de calidad obtenidos en la web, como soporte de información de los contenidos docentes. El objetivo principal es que las herramientas propuestas permitan profundizar en la materia de forma más atractiva y amena, así como fomentar la comunicación entre alumnos y profesores. Este modelo se ha implementado dentro de las clases de Matemáticas I del Grado en Ingeniería Electrónica Industrial y Automática, tanto en la teoría como en las prácticas de aula e informáticas.

[EN] One of the ways to increase students' motivation and participation in the classroom is to propose a wide variety of resources and activities so that the teaching materials to be used are suitable for the largest possible number of students. Today's students have grown up in an environment where technological supports are part of their daily lives. For this reason, this work proposes the incorporation of Information and Communication Technologies (TIC) together with other quality materials as a medium for information on teaching content. The main objective of this methodology is that the proposed tools allow learning the subject in a more attractive and enjoyable way, as well as promoting communication between students and teachers. This model has been implemented within the Mathematics I classes of the Degree in Industrial Electronic and Automatic Engineering, both in theory and in classroom and computer practices., [ES] Una de las maneras de aumentar la motivación y la participación en las aulas por parte de los alumnos es el planteamiento de una gran variedad de recursos y actividades de forma que los materiales docentes a trabajar se adecuen al mayor número de alumnos posible. Los alumnos de hoy en día han crecido en un ámbito donde los soportes tecnológicos forman parte de su vida cotidiana. Por ello, en este trabajo se propone la incorporación de las Tecnologías de la Información y la Comunicación (TIC), junto con otros materiales de calidad obtenidos en la web, como soporte de información de los contenidos docentes. El objetivo principal es que las herramientas propuestas permitan profundizar en la materia de forma más atractiva y amena, así como fomentar la comunicación entre alumnos y profesores. Este modelo se ha implementado dentro de las clases de Matemáticas I del Grado en Ingeniería Electrónica Industrial y Automática, tanto en la teoría como en las prácticas de aula e informáticas.

[EN] One of the ways to increase students' motivation and participation in the classroom is to propose a wide variety of resources and activities so that the teaching materials to be used are suitable for the largest possible number of students. Today's students have grown up in an environment where technological supports are part of their daily lives. For this reason, this work proposes the incorporation of Information and Communication Technologies (TIC) together with other quality materials as a medium for information on teaching content. The main objective of this methodology is that the proposed tools allow learning the subject in a more attractive and enjoyable way, as well as promoting communication between students and teachers. This model has been implemented within the Mathematics I classes of the Degree in Industrial Electronic and Automatic Engineering, both in theory and in classroom and computer practices., [ES] Una de las maneras de aumentar la motivación y la participación en las aulas por parte de los alumnos es el planteamiento de una gran variedad de recursos y actividades de forma que los materiales docentes a trabajar se adecuen al mayor número de alumnos posible. Los alumnos de hoy en día han crecido en un ámbito donde los soportes tecnológicos forman parte de su vida cotidiana. Por ello, en este trabajo se propone la incorporación de las Tecnologías de la Información y la Comunicación (TIC), junto con otros materiales de calidad obtenidos en la web, como soporte de información de los contenidos docentes. El objetivo principal es que las herramientas propuestas permitan profundizar en la materia de forma más atractiva y amena, así como fomentar la comunicación entre alumnos y profesores. Este modelo se ha implementado dentro de las clases de Matemáticas I del Grado en Ingeniería Electrónica Industrial y Automática, tanto en la teoría como en las prácticas de aula e informáticas.

Spacecraft are expected to traverse enormous distances over long periods of time without an opportunity for maintenance, re-fueling, or repair, and, for interplanetary probes, no on-board crew to actively control the spacecraft configuration or flight path. Nevertheless, space technology has reached the stage when mining of space resources, space travel, and even colonization of other celestial bodies such as Mars and the Moon are being seriously considered. These ambitious aims call for spacecraft capable of self-controlled, self-adapting, and self-healing behavior. It is a tough challenge to address using traditional materials and approaches for their assembly. True interplanetary advances may only be attained using novel self-assembled and self-healing materials, which would allow for realization of next-generation spacecraft, where the concepts of adaptation and healing are at the core of every level of spacecraft design. Herein, recent achievements are captured and future directions in materials-driven development of space technology outlined.

Circular economy (CE) has been promoted worldwide as a strategy to reduce material use and to increase the material use efficiency by closing material loops at the societal level. The core concept of CE is to improve the circularity of material use through turning materials at the end of their service life into resources for others, however, there is very little information about the role of manufacturing in achieving CE. Using the concepts of dynamic material flow analysis and stock dynamics, this paper proposes a methodological approach to help understand the role of manufacturing in achieving CE. A number of other strategies such as material efficiency in conjunction with CE are also tested using the case of global steel use to draw conclusions.

Dynamic materials are artificially constructed in such a way that they may vary their characteristic properties in space or in time, or both, by an appropriate arrangement or control. These controlled changes in time can be provided by the application of an external (non-mechanical) field, or through a phase transition. In principle, all materials change their properties with time, but very slowly and smoothly. Changes in properties of dynamic materials should be realized in a short or quasi-nil time lapse and over a sufficiently large material region. Wave propagation is a characteristic feature for dynamic materials because it is also space and time dependent. As a simple example of the complex behavior of dynamic materials, the one-dimensional elastic wave propagation is studied numerically in periodic structures whose properties (mass density, elasticity) can be switched suddenly in space and in time. It is shown that dynamic materials have the ability to dynamically amplify, tune, and compress initial signals. The thermodynamically consistent high-resolution finite-volume numerical method is applied to the study of the wave propagation in dynamic materials. The extended analysis of the influence of inner reflections on the energy localization in the dynamic materials is presented.

A method for annual evaluation of recycling rates in material flows was established to enable a consistent analysis of resource utilizations. The algorithm to calculate the time-varying losses was derived based on a sound statistical approach that would be viable for both historical data and future predictions. This method eliminates the need for adjustable parameters and is solely based on input data of the material consumption and scrap collection. This article describes the model methodology and the calculation procedures to classify the societal scrap reserve from the amounts of losses, based on statistics. These statistical models contribute to establish a standardized method to obtain consistent results. Based on the method the lifetime of steel data was for the first time calculated on an annual basis for the steel usage as well as for the end of life scrap amount. This was done for the Swedish steel consumption and the global steel consumption between 1900 and 2013 as well as for future predictions between 2013 and 2060. The lifetime of steel was calculated to be higher in an industrialized country such as Sweden compared to the global average value. More specifically, the service lifetimes of EOL steel in Sweden and in the World were calculated to be 35 and 28 years in 2012, respectively. This novel approach of using system specific data on the lifetime of steel on an annual basis enables a possibility to evaluate recycling trends and potentials to increase the recycling rate., QC 20161121

This dissertation is composed of seven chapters, detailing advances within the area of sulfur polymer chemistry and processing, and highlights the relevance of the work to the fields of polymer science, energy storage, and optics that are enabled through the development of novel high sulfur-content copolymers as discussed in the following chapters. The first chapter is a review summarizing both the historical forays into utilization of elemental sulfur in high sulfur-content materials and the current research on the incorporation of sulfur into novel copolymers and composites for high value added applications such as energy production/storage, polymeric optical components, and dynamic/self-healing materials. Although recent efforts by the materials and polymer chemistry communities have afforded innovative sulfur containing materials, many studies fail to take advantage of the low cost and incredible abundance of sulfur by incorporating only minimal quantities into the end products. A fundamental challenge in the preparation of sulfur-containing polymers is simultaneous incorporation of high sulfur-content through facile chemical methods, to truly use the element as a novel feedstock in copolymerizations. Contributing to the challenge are the intrinsic limitations of sulfur (i.e., low miscibility with organic solvents, high crystallinity, and poor processability). The emphasis in chapter 1 is the critical development of utilizing sulfur as both a reagent and solvent in a bulk reaction, termed inverse vulcanization. Through this methodology we can directly prepare materials which retain the advantageous properties of elemental sulfur (i.e., high electrochemical capacity, high refractive index, and liable bond character), obviate the processing challenges, and enable precise control over composition and properties in a facile manner. The second chapter focuses on advancement in colloid synthesis, specifically an example mediated by in-situ reduction of organometallic

As a preliminary study to more complex situations of interest in small-scale technology, this paper envisages the elementary propagation properties of elastic waves in one-spatial dimension when some of the properties (mass density, elasticity) may vary suddenly in space or in time, the second case being of course more original. Combination of the two may be of even greater interest. Toward this goal, a critical examination of what happens to solutions at the crossing of pure space-like and time-like material discontinuities is given together with simple solutions for smooth transitions and numerical simulations in the discontinuous case. The effects on amplitude, speed of propagation, frequency changes and the appearance of a Doppler-like effect are demonstrated although the whole physical system remains linear.