Wieland Hill - Academia.edu (original) (raw)
Papers by Wieland Hill
Ullmann's Encyclopedia of Industrial Chemistry, 2000
A novel concept of a diode laser system developed by LIMO GmbH and called "ring-laser" ... more A novel concept of a diode laser system developed by LIMO GmbH and called "ring-laser" (patent pending) enables a very flexible, uncomplex, simultaneous welding of plastic parts with different shapes and with different sizes without any additional changes of the system. Another diode laser system, so called line generator (patent pending), which utilises LIMO-homogenisers can be used for contour or simultaneous welding of plastics. This system is characterized by its nearly top-hat beam profile with homogeneity better than +/-6 %. Additionally, its line length, line width and its operating distance can be adapted to the geometry of a process by the use of an appropriate type of homogenisers and lens systems. Due to its outstanding features this diode laser can be also used e.g. for simultaneous soldering, thermal surface treatment, transversal pumping of solid state lasers and also in the printing industry (computer-to-plate technology).A novel concept of a diode laser sys...
L'invention concerne un dispositif laser a semi-conducteur, comportant un element laser a sem... more L'invention concerne un dispositif laser a semi-conducteur, comportant un element laser a semi-conducteur (1, 21) ou une pluralite de lasers individuels montes en parallele, presentant une pluralite de surfaces de sortie (2, 3, 4, 5, 22, 23, 24), desquelles peut sortir une lumiere laser qui presente, dans une premiere direction (Y), une plus grande divergence que dans une deuxieme direction perpendiculaire a la premiere, ainsi qu'au moins un moyen de reflexion (7, 9, 16, 16', 28) place a distance des surfaces de sortie (2, 3, 4, 5, 22, 23, 24) a l'exterieur de l'element laser a semi-conducteur (1), comportant au moins une surface reflechissante (8, 10, 11, 12, 13, 17, 18, 19, 20, 29, 30, 31), qui peut reflechir au moins des parties de la lumiere laser sortant de l'element laser a semi-conducteur (1, 21) ou des lasers individuels a travers les surfaces de sortie (2, 3, 4, 5, 22, 23, 24) dans l'element laser a semi-conducteur (1, 21) ou dans les lasers indi...
Vorrichtung zur Erzeugung eines linienartigen Fokusbereichs (12) einer Laserlichtquelle, umfassen... more Vorrichtung zur Erzeugung eines linienartigen Fokusbereichs (12) einer Laserlichtquelle, umfassend mindestens einen Halbleiterlaser (1) mit mindestens einem emittierenden Abschnitt (2), wobei die Divergenz des von diesem mindestens einen emittierenden Abschnitt (2) ausgehenden Laserlichtes (3) in der Fast-Axis-Richtung (Y) groser ist als in der dazu senkrechten Slow-Axis-Richtung (X), Fast-Axis-Kollimationsmittel (4) fur die Kollimierung des aus dem mindestens einen emittierenden Abschnitt (2) austretenden Laserlichtes (3) hinsichtlich der Fast-Axis-Richtung (Y), Homogenisatormittel (8, 13) zur Homogenisierung des von den Fast-Axis-Kollimationmitteln (4) kollimierten Laserlichtes (3) sowie Fokussiermittel (11) zur Fokussierung des von den Homogenisatormitteln (8, 13) ausgehenden Laserlichtes (10) in einen linienartigen Fokusbereich (12), wobei die Homogenisatormittel (8, 13) derart gestaltet sind, dass sie das Laserlicht (3) nur hinsichtlich der Slow-Axis-Richtung (X) homogenisieren.
Given the increased awareness and sensitivity with regard to safety aspects in the transportation... more Given the increased awareness and sensitivity with regard to safety aspects in the transportation of hazardous media, advanced and (locally) precise monitoring of a pipeline’s condition is absolutely essential. Especially new pipeline projects always offer a good opportunity for installing a monitoring system that is precisely matched to the relevant needs. The present article describes and evaluates a technology that monitors strain and temperature by means of a fiber optic cable. This method, which was applied in conjunction with a test pipe string, was presented at the Oldenburg Pipeline Forum 2016. Unlike conventional monitoring or fiber-optic measuring methods, it determines strain and temperature changes directly on the coated pipe body with meter accuracy. It shows that the fiber optic cables used not only survive the cement coating process completely undamaged, but also, in conjunction with the measuring and analyzing unit, allow strain as a result of mechanical deformation to be determined with high accuracy. At the same time, the condition of a pipeline in terms of its residual load-bearing capacity can be assessed both over its service life as well as during and after unforeseen incidents. This can provide a valuable contribution towards the financial and ecological sustainability of pipeline operation in that damage incidents can be avoided or their impact reduced.
L'invention concerne un dispositif d'homogeneisation de la lumiere, comprenant au moins d... more L'invention concerne un dispositif d'homogeneisation de la lumiere, comprenant au moins deux mosaiques de lentilles cylindriques (17, 20) disposees l'une derriere l'autre et comportant dans chaque cas des lentilles cylindriques convexes et concaves (18, 19, 21, 22) disposees les unes a cote des autres de maniere alternee, dont les axes cylindriques sont alignes parallelement les unes aux autres. Dans la direction (X), dans laquelle les lentilles cylindriques (18, 19, 21, 22) sont disposees les uns a cote des autres, les lentilles cylindriques concaves (19) de la premiere mosaique de lentilles cylindriques (17) relevent d'une autre conception et presentent notamment une autre extension ou une autre courbure que les lentilles cylindriques concaves (22) de la seconde mosaique de lentilles cylindriques (20).
Optical Fiber Sensors Conference 2020 Special Edition, 2021
IEEE Transactions on Power Delivery, 2020
Угодою про асоціацію з Європейським Союзом Україна проголосила згоду на посилення співробітництва... more Угодою про асоціацію з Європейським Союзом Україна проголосила згоду на посилення співробітництва у сфері юстиції, свободи та безпеки з метою забезпечення верховенства права та поваги до прав і основоположних свобод людини, зміцнення судової влади, підвищення її ефективності, гарантування її незалежності та неупередженості. Таким чином міжнародні, зокрема європейські, стандарти у сфері судочинства повинні стати для нашої держави орієнтиром і пріоритетом під час проведення чергових реформ. the courts in the consideration of cases of administrative offenses disrespect for court with the introduction of appropriate changes or procedural codes, or the Code of Ukraine on Administrative Offenses.
26th International Conference on Optical Fiber Sensors, 2018
The Brillouin characteristics of two polyimide fibers have been measured down to liquid nitrogen ... more The Brillouin characteristics of two polyimide fibers have been measured down to liquid nitrogen temperature. An amplitude-based temperature measurement using spontaneous Brillouin scattering is demonstrated for a wide range of cryogenic temperatures.
Journal of Sensors and Sensor Systems
Gaining information on climatic conditions in subway tunnels is the key to predicting the propaga... more Gaining information on climatic conditions in subway tunnels is the key to predicting the propagation of smoke or toxic gases in these infrastructures in the case of a fire or a terrorist attack. As anemometer measurements are not economically suitable, the employment of alternative monitoring methods is necessary. High-resolution temperature sensing with Raman optical frequency domain reflectometry (OFDR) using optical communication fiber cables shows great potential as it allows the surveillance of several kilometers of underground transport facilities without the need for installing sensing equipment in the tunnels. This paper presents first results of a study using this approach for monitoring subway tunnels. In the Berlin subway, temperature data gathered from newly installed as well as pre-installed communication cables were evaluated and compared to reference data from temperature loggers. Results are very promising as high correlations between all data can be achieved showing the potential of this approach.
Analytical Chemistry, 1975
CIRED - Open Access Proceedings Journal
This paper presents a new approach for continuous safeguarding of the accuracy of real-time therm... more This paper presents a new approach for continuous safeguarding of the accuracy of real-time thermal rating (RTTR) predictions of power cables. Comparisons of RTTR predictions with (slow) finite element simulations are suited for an offline validation of thermal models before they are deployed in the field. However, the accuracy of RTTR predictions does not only depend on the accuracy of the models but also on variations of ambient parameters and other external influences such as heat sources. Therefore, an on-site real-time evaluation of the rating accuracy is required for safeguarding the quality of RTTR predictions and finally for relying on those predictions in the safe operation of power cables.
IEEE Transactions on Power Delivery
Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases
... Institute of Physical Chemistry, Academy of Sciences of the German Democratic Republic, Berli... more ... Institute of Physical Chemistry, Academy of Sciences of the German Democratic Republic, Berlin-1 199, German Democratic Republic Boris N. Shelimov ... Volume and Mass Spectroscopic Analysis The working volume of 365 cm3 consisted of a sample cell, a McLeod gauge, and ...
Laser Technik Journal
Refraktive Mikrooptiken ermöglichen die Kollimation, Homogenisierung und Formung der Strahlung vo... more Refraktive Mikrooptiken ermöglichen die Kollimation, Homogenisierung und Formung der Strahlung von Hochleistungslasern entsprechend den Erfordernissen verschiedener industrieller Anwendungsbereiche.
Sixth European Workshop on Optical Fibre Sensors, 2016
Proceedings of Spie the International Society For Optical Engineering, May 1, 2011
Distributed temperature sensing (DTS) of long distance power cables is shown to provide valuable ... more Distributed temperature sensing (DTS) of long distance power cables is shown to provide valuable information for cable design optimisation and proper operation of wind farms. The long range sensing is enabled by using the Raman-OFDR (optical frequency domain reflectometry) technology in single-mode fibres. Raman-OFDR uses a modulated continuous wave laser for detection. The low peak power minimizes stimulated Raman-scattering in
Applied Spectroscopy, Sep 1, 1997
ABSTRACT
Ullmann's Encyclopedia of Industrial Chemistry, 2000
A novel concept of a diode laser system developed by LIMO GmbH and called "ring-laser" ... more A novel concept of a diode laser system developed by LIMO GmbH and called "ring-laser" (patent pending) enables a very flexible, uncomplex, simultaneous welding of plastic parts with different shapes and with different sizes without any additional changes of the system. Another diode laser system, so called line generator (patent pending), which utilises LIMO-homogenisers can be used for contour or simultaneous welding of plastics. This system is characterized by its nearly top-hat beam profile with homogeneity better than +/-6 %. Additionally, its line length, line width and its operating distance can be adapted to the geometry of a process by the use of an appropriate type of homogenisers and lens systems. Due to its outstanding features this diode laser can be also used e.g. for simultaneous soldering, thermal surface treatment, transversal pumping of solid state lasers and also in the printing industry (computer-to-plate technology).A novel concept of a diode laser sys...
L'invention concerne un dispositif laser a semi-conducteur, comportant un element laser a sem... more L'invention concerne un dispositif laser a semi-conducteur, comportant un element laser a semi-conducteur (1, 21) ou une pluralite de lasers individuels montes en parallele, presentant une pluralite de surfaces de sortie (2, 3, 4, 5, 22, 23, 24), desquelles peut sortir une lumiere laser qui presente, dans une premiere direction (Y), une plus grande divergence que dans une deuxieme direction perpendiculaire a la premiere, ainsi qu'au moins un moyen de reflexion (7, 9, 16, 16', 28) place a distance des surfaces de sortie (2, 3, 4, 5, 22, 23, 24) a l'exterieur de l'element laser a semi-conducteur (1), comportant au moins une surface reflechissante (8, 10, 11, 12, 13, 17, 18, 19, 20, 29, 30, 31), qui peut reflechir au moins des parties de la lumiere laser sortant de l'element laser a semi-conducteur (1, 21) ou des lasers individuels a travers les surfaces de sortie (2, 3, 4, 5, 22, 23, 24) dans l'element laser a semi-conducteur (1, 21) ou dans les lasers indi...
Vorrichtung zur Erzeugung eines linienartigen Fokusbereichs (12) einer Laserlichtquelle, umfassen... more Vorrichtung zur Erzeugung eines linienartigen Fokusbereichs (12) einer Laserlichtquelle, umfassend mindestens einen Halbleiterlaser (1) mit mindestens einem emittierenden Abschnitt (2), wobei die Divergenz des von diesem mindestens einen emittierenden Abschnitt (2) ausgehenden Laserlichtes (3) in der Fast-Axis-Richtung (Y) groser ist als in der dazu senkrechten Slow-Axis-Richtung (X), Fast-Axis-Kollimationsmittel (4) fur die Kollimierung des aus dem mindestens einen emittierenden Abschnitt (2) austretenden Laserlichtes (3) hinsichtlich der Fast-Axis-Richtung (Y), Homogenisatormittel (8, 13) zur Homogenisierung des von den Fast-Axis-Kollimationmitteln (4) kollimierten Laserlichtes (3) sowie Fokussiermittel (11) zur Fokussierung des von den Homogenisatormitteln (8, 13) ausgehenden Laserlichtes (10) in einen linienartigen Fokusbereich (12), wobei die Homogenisatormittel (8, 13) derart gestaltet sind, dass sie das Laserlicht (3) nur hinsichtlich der Slow-Axis-Richtung (X) homogenisieren.
Given the increased awareness and sensitivity with regard to safety aspects in the transportation... more Given the increased awareness and sensitivity with regard to safety aspects in the transportation of hazardous media, advanced and (locally) precise monitoring of a pipeline’s condition is absolutely essential. Especially new pipeline projects always offer a good opportunity for installing a monitoring system that is precisely matched to the relevant needs. The present article describes and evaluates a technology that monitors strain and temperature by means of a fiber optic cable. This method, which was applied in conjunction with a test pipe string, was presented at the Oldenburg Pipeline Forum 2016. Unlike conventional monitoring or fiber-optic measuring methods, it determines strain and temperature changes directly on the coated pipe body with meter accuracy. It shows that the fiber optic cables used not only survive the cement coating process completely undamaged, but also, in conjunction with the measuring and analyzing unit, allow strain as a result of mechanical deformation to be determined with high accuracy. At the same time, the condition of a pipeline in terms of its residual load-bearing capacity can be assessed both over its service life as well as during and after unforeseen incidents. This can provide a valuable contribution towards the financial and ecological sustainability of pipeline operation in that damage incidents can be avoided or their impact reduced.
L'invention concerne un dispositif d'homogeneisation de la lumiere, comprenant au moins d... more L'invention concerne un dispositif d'homogeneisation de la lumiere, comprenant au moins deux mosaiques de lentilles cylindriques (17, 20) disposees l'une derriere l'autre et comportant dans chaque cas des lentilles cylindriques convexes et concaves (18, 19, 21, 22) disposees les unes a cote des autres de maniere alternee, dont les axes cylindriques sont alignes parallelement les unes aux autres. Dans la direction (X), dans laquelle les lentilles cylindriques (18, 19, 21, 22) sont disposees les uns a cote des autres, les lentilles cylindriques concaves (19) de la premiere mosaique de lentilles cylindriques (17) relevent d'une autre conception et presentent notamment une autre extension ou une autre courbure que les lentilles cylindriques concaves (22) de la seconde mosaique de lentilles cylindriques (20).
Optical Fiber Sensors Conference 2020 Special Edition, 2021
IEEE Transactions on Power Delivery, 2020
Угодою про асоціацію з Європейським Союзом Україна проголосила згоду на посилення співробітництва... more Угодою про асоціацію з Європейським Союзом Україна проголосила згоду на посилення співробітництва у сфері юстиції, свободи та безпеки з метою забезпечення верховенства права та поваги до прав і основоположних свобод людини, зміцнення судової влади, підвищення її ефективності, гарантування її незалежності та неупередженості. Таким чином міжнародні, зокрема європейські, стандарти у сфері судочинства повинні стати для нашої держави орієнтиром і пріоритетом під час проведення чергових реформ. the courts in the consideration of cases of administrative offenses disrespect for court with the introduction of appropriate changes or procedural codes, or the Code of Ukraine on Administrative Offenses.
26th International Conference on Optical Fiber Sensors, 2018
The Brillouin characteristics of two polyimide fibers have been measured down to liquid nitrogen ... more The Brillouin characteristics of two polyimide fibers have been measured down to liquid nitrogen temperature. An amplitude-based temperature measurement using spontaneous Brillouin scattering is demonstrated for a wide range of cryogenic temperatures.
Journal of Sensors and Sensor Systems
Gaining information on climatic conditions in subway tunnels is the key to predicting the propaga... more Gaining information on climatic conditions in subway tunnels is the key to predicting the propagation of smoke or toxic gases in these infrastructures in the case of a fire or a terrorist attack. As anemometer measurements are not economically suitable, the employment of alternative monitoring methods is necessary. High-resolution temperature sensing with Raman optical frequency domain reflectometry (OFDR) using optical communication fiber cables shows great potential as it allows the surveillance of several kilometers of underground transport facilities without the need for installing sensing equipment in the tunnels. This paper presents first results of a study using this approach for monitoring subway tunnels. In the Berlin subway, temperature data gathered from newly installed as well as pre-installed communication cables were evaluated and compared to reference data from temperature loggers. Results are very promising as high correlations between all data can be achieved showing the potential of this approach.
Analytical Chemistry, 1975
CIRED - Open Access Proceedings Journal
This paper presents a new approach for continuous safeguarding of the accuracy of real-time therm... more This paper presents a new approach for continuous safeguarding of the accuracy of real-time thermal rating (RTTR) predictions of power cables. Comparisons of RTTR predictions with (slow) finite element simulations are suited for an offline validation of thermal models before they are deployed in the field. However, the accuracy of RTTR predictions does not only depend on the accuracy of the models but also on variations of ambient parameters and other external influences such as heat sources. Therefore, an on-site real-time evaluation of the rating accuracy is required for safeguarding the quality of RTTR predictions and finally for relying on those predictions in the safe operation of power cables.
IEEE Transactions on Power Delivery
Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases
... Institute of Physical Chemistry, Academy of Sciences of the German Democratic Republic, Berli... more ... Institute of Physical Chemistry, Academy of Sciences of the German Democratic Republic, Berlin-1 199, German Democratic Republic Boris N. Shelimov ... Volume and Mass Spectroscopic Analysis The working volume of 365 cm3 consisted of a sample cell, a McLeod gauge, and ...
Laser Technik Journal
Refraktive Mikrooptiken ermöglichen die Kollimation, Homogenisierung und Formung der Strahlung vo... more Refraktive Mikrooptiken ermöglichen die Kollimation, Homogenisierung und Formung der Strahlung von Hochleistungslasern entsprechend den Erfordernissen verschiedener industrieller Anwendungsbereiche.
Sixth European Workshop on Optical Fibre Sensors, 2016
Proceedings of Spie the International Society For Optical Engineering, May 1, 2011
Distributed temperature sensing (DTS) of long distance power cables is shown to provide valuable ... more Distributed temperature sensing (DTS) of long distance power cables is shown to provide valuable information for cable design optimisation and proper operation of wind farms. The long range sensing is enabled by using the Raman-OFDR (optical frequency domain reflectometry) technology in single-mode fibres. Raman-OFDR uses a modulated continuous wave laser for detection. The low peak power minimizes stimulated Raman-scattering in
Applied Spectroscopy, Sep 1, 1997
ABSTRACT