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  • Other research product . Other ORP type . 2022
    Open Access German
    Country: Germany

    Die Enzyklopädie Recht und Literatur / Encyclopedia of Law and Literature erschließt die interdisziplinäre Forschung zu den Wechselwirkungen zwischen Recht und Literatur in internationaler, rechts- wie literaturvergleichender Perspektive in deutscher und in englischer Sprache. In ausführlicheren Sachartikeln werden zentrale Teilbereiche des Themenfeldes und wichtige Aspekte des Verhältnisses von Recht und Literatur historisch und systematisch beleuchtet. Diskursprägende literarische Texte sowie Forschungsbeiträge zum Themenfeld "Recht und Literatur" werden zudem durch Personenartikel zu einschlägigen Autoren erschlossen. Neben der durchgehenden Aufarbeitung der einschlägigen englisch- und deutschsprachigen Forschung legt die Enzyklopädie besonderes Augenmerk auf internationale Austauschprozesse im europäischen Rahmen sowie über diesen hinaus. The interdisciplinary Encyclopedia of Law and Literature provides a comprehensive, reliable and authoritative reference to accumulated and current knowledge and research in the field of law and literature. It explores this interdisciplinary research field in its full depth and from a comparative perspective including comparative law as well as comparative literature. Central areas in the field, major concepts and important aspects of the relation between law and literature will be covered in substantial articles, in a historical as well as in a systematic perspective. Relevant literary texts or authors, legal cases and influential research contributions will also be discussed. In addition to a continuous review of relevant research in English and German, the encyclopedia pays special attention to international exchange processes within as well as beyond the European framework.

  • Open Access English
    Authors: 
    Shkolnykova, Mariia; Steffens, Lasse; Wedemeier, Jan;
    Publisher: Universität Bremen
    Country: Germany

    Against the background of the current political developments in Central and Eastern European (CEE) countries, like Ukraine, Poland, and Romania, the question arises what role the transformation of the economy and the resulting innovation linkages have played in these countries. This paper addresses this issue by exploring the impact of economic and institutional dimensions on the development of CEE countries, thereby explicitly distinguishing between European Union (EU) members and non-members. First of all, the performance development of the Gross Domestic Product (GDP) of the CEE countries and Western European countries is observed. In a further analysis step, the development of EU members is compared with that of CEE countries that are non-members of the EU. This paper estimates the impact of such factors as innovation, institutions, and political practices on the economic development of 37 European countries for the period from 2000 until 2020 by using a panel regression. The results of the analysis show that institutions matter, especially for non-EU-member CEE countries. Stable institutions—such as freedom of the press, freedom of expression, but also high levels of the Human Development Index—help countries to achieve a higher income development over time. The role of the innovative ability of countries is also decisive for a positive development. 2209

  • Open Access German
    Authors: 
    Vöing, Nerea; Reisas, Sabine; Arnold, Maik;
    Country: Germany

    In den letzten Jahren hat sich an den Hochschulen und Universitäten im deutschsprachigen Raum eine große Vielfalt des Scholarship of Teaching and Learning (SoTL) herausgebildet. An der zunehmenden Verbreitung und Rezeption ist zu erkennen, dass SoTL vielfältige Potentiale für die (Weiter-)Entwicklung und engere Verzahnung fachspezifischer Lehre mit dem hochschuldidaktischen Gesamtanspruch aufweist. Ziel dieses Forschungsbands ist es, auf Basis einer Bestandsaufnahme ausgewählter aktueller SoTL-Projekte an deutschsprachigen Hochschulen eine forschungsgeleitete Auseinandersetzung mit der Hochschullehre zu führen, in der insbesondere Lehrende, Forschende und Hochschuldidaktiker*innen, aber auch Studierende involviert sind. Der Band versammelt Beiträge zu den Themenfeldern Entwicklung innovativer Lehrformate und Anwendungen, Förderung reflexiver Kompetenzen sowie SoTL und Gemeinschaft – Institutions-, disziplinen- und statusgruppenübergreifende Zusammenarbeit und richtet sich an Hochschullehrende und Forschende aller Fachdisziplinen.

  • Other research product . Other ORP type . 2022
    Open Access English
    Authors: 
    Simons, Marcel; Radel, Tim;
    Publisher: BIAS Verlag
    Country: Germany

    To meet the increasing trend of miniaturization, new (non-conventional) manufacturing processes are constantly being developed. The laser chemical process describes one of these non-conventional removal process in the microscale, based on the thermochemical dissolution of metals. To determine the influence of electrolyte concentrations, linear cavities were created in Titanium Grade 1 using phosphoric acid and sulfuric acid with different concentrations. The experimental results show that as the electrolyte concentration increases, the process window is reduced. One possibility for this is, as the electrolyte concentration increases, the viscosity increases, as well. With increasing viscosity, the electrolyte boiling process, which causes the shielding effect of the gas bubbles becomes more significant. Due to the increasing conductivity of the electrolyte at higher concentrations, the laser chemical removal rate increases within the process window at constant laser power. The maximum removal rate is observed at the maximum conductivity of the electrolyte. Deutsche Forschungsgemeinschaft DFG 32 36

  • Open Access English
    Authors: 
    Müller, Sven; Mattulat, Thorsten; Woizeschke, Peer;
    Publisher: BIAS Verlag
    Country: Germany

    For the thermal joining of aluminum and titanium, the approach of solely melting the aluminum joining partner, while the titanium partner stays in the solid form, has been commonplace since 1996. This is done to limit the formation of a brittle intermetallic compound layer in the interface. In case of additive manufacturing with titanium powder and aluminum substrates, this approach is not transferrable because the titanium powder has to be melted to create the part. In this study, titanium samples were additively manufactured onto aluminum substrates using a commercial laser powder bed fusion (LPBF) machine. The influences of the energy density during the process on the sample porosity, the characteristics of the interface between sample and substrate, as well as the interfacial tensile strength are analyzed. Despite the melting of both materials, a great potential for high interfacial tensile strength has been found. 41 46

  • Other research product . Other ORP type . 2022
    Open Access English
    Authors: 
    Valentino, Tobias; Jägle, Eric A.; Radel, Tim;
    Publisher: BIAS Verlag
    Country: Germany

    The identification of material properties at high strain rates is of considerable technical interest, e.g., in applications for passenger safety-related parts which are expected to absorb energy in case of collisions. To additionally meet the requirements of a rapid and resource-efficient materials characterization, a novel highspeed hardness testing method based on laser-induced shock waves was investigated. The principal applicability of this laser-induced shockwave indentation technique for materials characterization at high strain rates is shown. Deutsche Forschungsgemeinschaft DFG 15 17

  • Open Access English
    Authors: 
    Rathmann, Lewin; Beste, L. H.; Faue, P. J.; Richter, B.; Klingbeil, K.; Radel, Tim; Pfefferkorn, F. E.;
    Publisher: BIAS Verlag
    Country: Germany

    Despite notable improvements in the laser-based powder bed fusion of metals (PBF-LB/M) in recent years, residual porosity is still an issue. Near surface pores can affect the functional properties of PBF components, such as their fatigue life, yield strength, or corrosion behavior. To help address the challenge, this work shows that laser polishing decreases the surface roughness while also creating a highly dense sub-surface region of PBF parts with only microscale pores remaining. Deutsche Forschungsgemeinschaft DFG, U.S. National Science Foundation 37 40

  • Open Access English
    Authors: 
    Stephen, Andreas; Lenz, Bastian; Hellenbrand, Gerrit;
    Publisher: BIAS Verlag
    Country: Germany

    In the aircraft industry spline-joints are used for the connection of subassemblies in geared turbofans. Besides the power transmission, spline-joints are used to compensate deviations in the shaft system, such as angular or axial misalignments. By decoupling the subassemblies, constraining forces are reduced, which affects the dimensioning of the surrounding components. Increasing the load capacity of spline-joints enables a lean and efficient design of the components. The wear behavior of such heavily loaded splines can be improved by multi-layered coatings deposited e. g. by physical vapor deposi-tion (PVD). Further improvements can be realized by an additional laser structured surface topology, which includes an arrangement of semi-spheres in the coating system with diameters in the micrometer range. These semi-spheres can either serve as a micro pocket for lubrications or are applied before the final coating step to be replenished with a hard lubricant layer. This paper addresses this subject by presenting the manufacturing process of splines with focus on the laser texturing process. Clean Sky 2 initiative, Horizon 2020 European Union Funding for Research and Innovation 28 31

  • Open Access English
    Authors: 
    Langebeck, Anika; Bohlen, Annika;
    Publisher: BIAS Verlag
    Country: Germany

    Laser melt injection (LMI) is used to improve abrasive wear resistance by building a metal matrix composite (MMC) layer in highly loaded tool surfaces. But LMI for highly conductive and highly reflective materials like copper can be very challenging. Nowadays high-power laser beam sources with visible wavelengths are available enabling LMI in these materials. This paper shows a suitable process window for LMI with 515 nm wavelength laser in pure copper with spherical fused tungsten carbide as reinforcing phase. High-quality MMC can be manufactured by using laser power intensities in the range of 104 W/cm² and conduction heating of the matrix mate-rial between 300 °C and 400 °C. The microstructure exhibits only a few imperfections and has a high particle content of 44 %. Industrial Collective Research IGF, Forschungsvereinigung Schweißen und verwandte Verfahren e. V. DVS, Federal Ministry for Economic Affairs and Climate Action BMWK, Industrial Research Associations AiF 11 14

  • Open Access English
    Authors: 
    Pordzik, Ronald; Mattulat, Thorsten;
    Publisher: BIAS Verlag
    Country: Germany

    Laser brazing is a joining technique widely applied in industrial manufacturing such as automotive production. In order to establish a stable brazing process free of defects, it is necessary to support the process with a track control. Whereas conventional laser brazing processes rely on tactile track control based on the mechanical interaction between the brazing wire and the substrate surface, new approaches like the reflection-assisted laser brazing require vision-based detection of the joining interface for track control as the brazing wire is already molten when contacting the substrate surface. Especially in the case of brazing flange joints the visual detection of the interface position is challenging given the limited visual accessibility of the joint interface. Therefore, in order to reliably detect the interface position, a semi-analytic algorithm is introduced based on the signals from a laser triangulation sensor scanning the joint geometry ahead of the process zone. Hereby information about the joint geometry is used to extrapolate the surface contours of the joining partners into areas that are not visible to the sensor. The algorithm was successfully tested on 90° and 45° flange joints resulting in an uncertainty in the determination of the interface position of less than ±0.5 mm. Federal Ministry for Economic Affairs and Energy (BMWi), German Federation of Industrial Re-search Associations (AiF), Central Innovations of Medium-Sized 58 64

Advanced search in
Research products
arrow_drop_down
Searching FieldsTerms
Any field
arrow_drop_down
includes
arrow_drop_down
Include:
8,283 Research products, page 1 of 829
  • Other research product . Other ORP type . 2022
    Open Access German
    Country: Germany

    Die Enzyklopädie Recht und Literatur / Encyclopedia of Law and Literature erschließt die interdisziplinäre Forschung zu den Wechselwirkungen zwischen Recht und Literatur in internationaler, rechts- wie literaturvergleichender Perspektive in deutscher und in englischer Sprache. In ausführlicheren Sachartikeln werden zentrale Teilbereiche des Themenfeldes und wichtige Aspekte des Verhältnisses von Recht und Literatur historisch und systematisch beleuchtet. Diskursprägende literarische Texte sowie Forschungsbeiträge zum Themenfeld "Recht und Literatur" werden zudem durch Personenartikel zu einschlägigen Autoren erschlossen. Neben der durchgehenden Aufarbeitung der einschlägigen englisch- und deutschsprachigen Forschung legt die Enzyklopädie besonderes Augenmerk auf internationale Austauschprozesse im europäischen Rahmen sowie über diesen hinaus. The interdisciplinary Encyclopedia of Law and Literature provides a comprehensive, reliable and authoritative reference to accumulated and current knowledge and research in the field of law and literature. It explores this interdisciplinary research field in its full depth and from a comparative perspective including comparative law as well as comparative literature. Central areas in the field, major concepts and important aspects of the relation between law and literature will be covered in substantial articles, in a historical as well as in a systematic perspective. Relevant literary texts or authors, legal cases and influential research contributions will also be discussed. In addition to a continuous review of relevant research in English and German, the encyclopedia pays special attention to international exchange processes within as well as beyond the European framework.

  • Open Access English
    Authors: 
    Shkolnykova, Mariia; Steffens, Lasse; Wedemeier, Jan;
    Publisher: Universität Bremen
    Country: Germany

    Against the background of the current political developments in Central and Eastern European (CEE) countries, like Ukraine, Poland, and Romania, the question arises what role the transformation of the economy and the resulting innovation linkages have played in these countries. This paper addresses this issue by exploring the impact of economic and institutional dimensions on the development of CEE countries, thereby explicitly distinguishing between European Union (EU) members and non-members. First of all, the performance development of the Gross Domestic Product (GDP) of the CEE countries and Western European countries is observed. In a further analysis step, the development of EU members is compared with that of CEE countries that are non-members of the EU. This paper estimates the impact of such factors as innovation, institutions, and political practices on the economic development of 37 European countries for the period from 2000 until 2020 by using a panel regression. The results of the analysis show that institutions matter, especially for non-EU-member CEE countries. Stable institutions—such as freedom of the press, freedom of expression, but also high levels of the Human Development Index—help countries to achieve a higher income development over time. The role of the innovative ability of countries is also decisive for a positive development. 2209

  • Open Access German
    Authors: 
    Vöing, Nerea; Reisas, Sabine; Arnold, Maik;
    Country: Germany

    In den letzten Jahren hat sich an den Hochschulen und Universitäten im deutschsprachigen Raum eine große Vielfalt des Scholarship of Teaching and Learning (SoTL) herausgebildet. An der zunehmenden Verbreitung und Rezeption ist zu erkennen, dass SoTL vielfältige Potentiale für die (Weiter-)Entwicklung und engere Verzahnung fachspezifischer Lehre mit dem hochschuldidaktischen Gesamtanspruch aufweist. Ziel dieses Forschungsbands ist es, auf Basis einer Bestandsaufnahme ausgewählter aktueller SoTL-Projekte an deutschsprachigen Hochschulen eine forschungsgeleitete Auseinandersetzung mit der Hochschullehre zu führen, in der insbesondere Lehrende, Forschende und Hochschuldidaktiker*innen, aber auch Studierende involviert sind. Der Band versammelt Beiträge zu den Themenfeldern Entwicklung innovativer Lehrformate und Anwendungen, Förderung reflexiver Kompetenzen sowie SoTL und Gemeinschaft – Institutions-, disziplinen- und statusgruppenübergreifende Zusammenarbeit und richtet sich an Hochschullehrende und Forschende aller Fachdisziplinen.

  • Other research product . Other ORP type . 2022
    Open Access English
    Authors: 
    Simons, Marcel; Radel, Tim;
    Publisher: BIAS Verlag
    Country: Germany

    To meet the increasing trend of miniaturization, new (non-conventional) manufacturing processes are constantly being developed. The laser chemical process describes one of these non-conventional removal process in the microscale, based on the thermochemical dissolution of metals. To determine the influence of electrolyte concentrations, linear cavities were created in Titanium Grade 1 using phosphoric acid and sulfuric acid with different concentrations. The experimental results show that as the electrolyte concentration increases, the process window is reduced. One possibility for this is, as the electrolyte concentration increases, the viscosity increases, as well. With increasing viscosity, the electrolyte boiling process, which causes the shielding effect of the gas bubbles becomes more significant. Due to the increasing conductivity of the electrolyte at higher concentrations, the laser chemical removal rate increases within the process window at constant laser power. The maximum removal rate is observed at the maximum conductivity of the electrolyte. Deutsche Forschungsgemeinschaft DFG 32 36

  • Open Access English
    Authors: 
    Müller, Sven; Mattulat, Thorsten; Woizeschke, Peer;
    Publisher: BIAS Verlag
    Country: Germany

    For the thermal joining of aluminum and titanium, the approach of solely melting the aluminum joining partner, while the titanium partner stays in the solid form, has been commonplace since 1996. This is done to limit the formation of a brittle intermetallic compound layer in the interface. In case of additive manufacturing with titanium powder and aluminum substrates, this approach is not transferrable because the titanium powder has to be melted to create the part. In this study, titanium samples were additively manufactured onto aluminum substrates using a commercial laser powder bed fusion (LPBF) machine. The influences of the energy density during the process on the sample porosity, the characteristics of the interface between sample and substrate, as well as the interfacial tensile strength are analyzed. Despite the melting of both materials, a great potential for high interfacial tensile strength has been found. 41 46

  • Other research product . Other ORP type . 2022
    Open Access English
    Authors: 
    Valentino, Tobias; Jägle, Eric A.; Radel, Tim;
    Publisher: BIAS Verlag
    Country: Germany

    The identification of material properties at high strain rates is of considerable technical interest, e.g., in applications for passenger safety-related parts which are expected to absorb energy in case of collisions. To additionally meet the requirements of a rapid and resource-efficient materials characterization, a novel highspeed hardness testing method based on laser-induced shock waves was investigated. The principal applicability of this laser-induced shockwave indentation technique for materials characterization at high strain rates is shown. Deutsche Forschungsgemeinschaft DFG 15 17

  • Open Access English
    Authors: 
    Rathmann, Lewin; Beste, L. H.; Faue, P. J.; Richter, B.; Klingbeil, K.; Radel, Tim; Pfefferkorn, F. E.;
    Publisher: BIAS Verlag
    Country: Germany

    Despite notable improvements in the laser-based powder bed fusion of metals (PBF-LB/M) in recent years, residual porosity is still an issue. Near surface pores can affect the functional properties of PBF components, such as their fatigue life, yield strength, or corrosion behavior. To help address the challenge, this work shows that laser polishing decreases the surface roughness while also creating a highly dense sub-surface region of PBF parts with only microscale pores remaining. Deutsche Forschungsgemeinschaft DFG, U.S. National Science Foundation 37 40

  • Open Access English
    Authors: 
    Stephen, Andreas; Lenz, Bastian; Hellenbrand, Gerrit;
    Publisher: BIAS Verlag
    Country: Germany

    In the aircraft industry spline-joints are used for the connection of subassemblies in geared turbofans. Besides the power transmission, spline-joints are used to compensate deviations in the shaft system, such as angular or axial misalignments. By decoupling the subassemblies, constraining forces are reduced, which affects the dimensioning of the surrounding components. Increasing the load capacity of spline-joints enables a lean and efficient design of the components. The wear behavior of such heavily loaded splines can be improved by multi-layered coatings deposited e. g. by physical vapor deposi-tion (PVD). Further improvements can be realized by an additional laser structured surface topology, which includes an arrangement of semi-spheres in the coating system with diameters in the micrometer range. These semi-spheres can either serve as a micro pocket for lubrications or are applied before the final coating step to be replenished with a hard lubricant layer. This paper addresses this subject by presenting the manufacturing process of splines with focus on the laser texturing process. Clean Sky 2 initiative, Horizon 2020 European Union Funding for Research and Innovation 28 31

  • Open Access English
    Authors: 
    Langebeck, Anika; Bohlen, Annika;
    Publisher: BIAS Verlag
    Country: Germany

    Laser melt injection (LMI) is used to improve abrasive wear resistance by building a metal matrix composite (MMC) layer in highly loaded tool surfaces. But LMI for highly conductive and highly reflective materials like copper can be very challenging. Nowadays high-power laser beam sources with visible wavelengths are available enabling LMI in these materials. This paper shows a suitable process window for LMI with 515 nm wavelength laser in pure copper with spherical fused tungsten carbide as reinforcing phase. High-quality MMC can be manufactured by using laser power intensities in the range of 104 W/cm² and conduction heating of the matrix mate-rial between 300 °C and 400 °C. The microstructure exhibits only a few imperfections and has a high particle content of 44 %. Industrial Collective Research IGF, Forschungsvereinigung Schweißen und verwandte Verfahren e. V. DVS, Federal Ministry for Economic Affairs and Climate Action BMWK, Industrial Research Associations AiF 11 14

  • Open Access English
    Authors: 
    Pordzik, Ronald; Mattulat, Thorsten;
    Publisher: BIAS Verlag
    Country: Germany

    Laser brazing is a joining technique widely applied in industrial manufacturing such as automotive production. In order to establish a stable brazing process free of defects, it is necessary to support the process with a track control. Whereas conventional laser brazing processes rely on tactile track control based on the mechanical interaction between the brazing wire and the substrate surface, new approaches like the reflection-assisted laser brazing require vision-based detection of the joining interface for track control as the brazing wire is already molten when contacting the substrate surface. Especially in the case of brazing flange joints the visual detection of the interface position is challenging given the limited visual accessibility of the joint interface. Therefore, in order to reliably detect the interface position, a semi-analytic algorithm is introduced based on the signals from a laser triangulation sensor scanning the joint geometry ahead of the process zone. Hereby information about the joint geometry is used to extrapolate the surface contours of the joining partners into areas that are not visible to the sensor. The algorithm was successfully tested on 90° and 45° flange joints resulting in an uncertainty in the determination of the interface position of less than ±0.5 mm. Federal Ministry for Economic Affairs and Energy (BMWi), German Federation of Industrial Re-search Associations (AiF), Central Innovations of Medium-Sized 58 64

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