Olaf Gelsen - Profile on Academia.edu (original) (raw)
Papers by Olaf Gelsen
computationally efficient methods. To address this, we have implemented a parallel Markov Chain M... more computationally efficient methods. To address this, we have implemented a parallel Markov Chain Monte Carlo scheme for sampling the posterior distribution.
ITE Technical Report, 1999
Las monografías originales remitidas para su publicación en esta colección deberán ser inéditas. ... more Las monografías originales remitidas para su publicación en esta colección deberán ser inéditas. El comité editorial, de acuerdo con la opinión del comité de redacción, decidirá sobre si procede o no la publicación, o bien propondrá modificaciones a los autores, notificándoles la fecha de admisión del trabajo. Los originales en castellano deberán llevar palabras clave y resumen en inglés. Deberán entregarse escritos en papel por duplicado y grabados en un disco de ordenador PC-compatible, de 3,5 (740 Kb) ó 5,25 pulgadas (360 Kb). El archivo en disco podrá corresponder a cualquiera de los siguientes formatos o programas: ASCII, DisplayWrite 4, DCA, RFT, Works, WordStar, WordPerfect, MS-Word, Multimate, XyWriter, PC-Tools, Ventura (indicar en la etiqueta del disco el procesador o formato empleado). Es preferible no incluir negrillas, cursivas, subrayados, paginación o cualquier otro tipo de formato en el documento grabado. No deben ponerse puntos y aparte vacíos para separar párrafos en el documento. En el texto que se entregará impreso en papel se incluirá un subrayado sencillo para los nombres de géneros y especies. Los apellidos de los autores citados en el texto se escribirán en MAYUSCULAS. La bibliografía irá al final del original y del archivo en disco, y deberá limitarse a los autores citados en el texto. Se dispondrán por orden alfabético de apellidos de autores citados y, dentro de cada autor, por orden cronológico. La referencia debe dar, por este orden, el apellido y a continuación las iniciales de los nombres propios del autor o autores, año de publicación, título completo del trabajo nombre de la revista, en abreviaturas usuales con subrayado sencillo, tomo y páginas primera y última. En el caso de libros se subrayará el título de los mismos y a continuación se pondrá la editorial, número de páginas y lugar de edición. Los esquemas y gráficos se realizarán con tinta china sobre papel vegetal en tamaño A4. Se incluirá escala gráfica si es necesario. Deberán llevar en el reverso escrito con lápiz el nombre del autor, número de orden y título resumido del trabajo. Los cuadros o tablas deberán ir numerados de forma independiente a los dibujos. En el archivo en disco, las columnas de las tablas o cuadros deberán separarse con un único tabulador entre cada dos columnas, y con punto y aparte al final de la última columna. En la copia en papel, las tablas y cuadros deberán tener el aspecto deseado. Los autores indicarán en el original el lugar en donde deben intercalarse las figuras y cuadros. Las leyendas de las figuras deberán ir en una hoja aparte, y después de la bibliografía en el documento en disco. Los autores recibirán un juego de pruebas de Imprenta para su corrección. Las modificaciones posteriores que se hicieran al texto original serán las de tipo gramatical o errores de impresión. Las correcciones que pudieran hacerse al texto del original serán con cargo a los autores. Las pruebas de imprenta deberán ser firmadas y devueltas en el plazo de quince días.
ITE Technical Report, 2000
Social acceptance and peer and romantic relationship self-efficacy were examined as salient facto... more Social acceptance and peer and romantic relationship self-efficacy were examined as salient factors related to social development among emerging adult (ages 18 to 25) survivors of pediatric cancers. Using a cross-sectional, within-groups methodology, relationships between cancer treatment intensity and peer and romantic relationship self-efficacy and social acceptance were assessed. Perceived health vulnerability, situational coping style, parent and peer attachment, and perceived physical attractiveness were explored as moderators of peer and romantic relationship self-efficacy and social acceptance. Additionally, social acceptance was examined within a cancer stereotyping framework. Fifty-two emerging adult survivors of pediatric cancers (54% male; mean (M) age = 21.38 years, standard deviation (SD) age = 3.11 years) completed self-report questionnaires. Participants were diagnosed between ages 5 and 19 (M age = 12.59 years, SD age = 4.57 years) and were at least six months post-active treatment (M time = 7.32 years, SD time = 4.46 years). Simultaneous regression analyses indicated that health vulnerability, coping style, parent and peer attachment, and physical attractiveness together accounted for a significant amount of variance in peer and romantic relationship self-efficacy and self-perceived social acceptance. There were significant main effects of perceptions of physical attractiveness and peer attachment on peer relationship self-efficacy and self-perceived social acceptance. There was also a main effect of perceived physical attractiveness on romantic relationship selfefficacy. However, treatment intensity was not significantly related to peer or romantic relationship self-efficacy or social acceptance. Furthermore, there were no significant moderating effects of health vulnerability, coping, parent or peer attachment, or physical attractiveness on the relationship between treatment intensity and peer or romantic relationship self-efficacy or social acceptance. In terms of social acceptance, participants believed that others" viewed them as more socially accepted than they viewed themselves. Participants also rated a hypothetical peer with cancer as less socially accepted than healthy peers. Results suggest greater perceived physical attractiveness and stronger attachment to peers may be strongly related to greater relationship confidence and feelings of being socially accepted. Survivors may also hold stereotyped views of their own level of social acceptance and the social acceptability of peers diagnosed with cancer. Future research and interventions implications are considered.
Le Journal de Physique Colloques, 1989
Resume : On decrit un appareil de diffusion qui perrnet 1'6tude des gels et des aerogels dans l a... more Resume : On decrit un appareil de diffusion qui perrnet 1'6tude des gels et des aerogels dans l a lumibre visible. Les formules permettant de corriger les resultats pour divers types de gbrn4ries sont explicitees. Nous reportons les resultats de diffusion obtenus pour des aerogels de silice ayant des densites de 71, 105 et 143 Kg/m3 ; les longueurs de correlation ac varient entre 10 et 25nm ; ces valeurs diminuent lorsque la densite augmente. Nous reportons aussi les resultats de diffusion de lumiere realises tors de la transformation sol-gel. Abstract -A scattering apparatus is described which allows the investigation of gels and aerogels with visible light. The correction formulas for various typical geometries are derived. Scattering data for silica aerogels with densities 71, 105 and 143 kg/mA3 are provided; the derived correlation lenghts a, are in the range 10 to 25 nm; they show a systematic decrease with increasing density. We also provide results for light scattering in a sol-gel process.
OLEDs & plastic electronics start to get serious
Speciality Chemicals, 2004
Comment on ‘‘Observation of the photorefractive effect in a polymer’’
Physical Review Letters, 1991
51.1: Invited Paper : Polymers for Efficient OLEDs
SID Symposium Digest of Technical Papers, 2000
Polymer light-emitting diodes (PLEDs) and displays based on polymer technology have made dramatic... more Polymer light-emitting diodes (PLEDs) and displays based on polymer technology have made dramatic progress during the last years. In particular, efficiency and device lifetime have improved to such a significant extent that first products will commercialized within this year. We report here on the technical status of materials and devices upon which this success is based. Efficiency and especially operational stability are now at a level which easily meets the requirements for a variety of applications, namely power efficiencies are well above 10 lm/W, operational lifetimes are exceeding 20000 hours at display brightness levels and room temperature). This progress has been achieved by the careful analysis of failure mechanisms and the systematic improvement of materials. The first products, i. e. back-lights (for LCD-displays), segmented displays, and finally passive-matrix-addressed low-information-content (LIC) graphical displays are described. Light emitting polymerss are now manufactured on industrial scale under high purity conditions; filling and packaging is done under a class 10 clean room condition. For details see H. Becker Paper 46.1.
Femtosecond Optical Absorption in Conjugated Polymers
Springer Series in Solid-State Sciences, 1992
We report transient absorption measurements using the pump and probe technique on poly(2,5 dimeth... more We report transient absorption measurements using the pump and probe technique on poly(2,5 dimethoxy-p-phenylene vinylene), DMPPV, and poly(p-phenylene vinylene), PPV. We observe a transient absorption in both materials, although a transient bleaching would be expected, and we discuss possible explanations for this behaviour.
Synthetic Metals, 2000
Ž .Ž. Poly p-phenylene vinylene s PPVs are promising materials for optoelectronic applications, e... more Ž .Ž. Poly p-phenylene vinylene s PPVs are promising materials for optoelectronic applications, especially for displays based on polymer Ž. light emitting diodes PLEDs. We report here our findings concerning defect structures in this class of materials and the implications of the discovered irregularities on important material properties, that is, the operational life in a PLED. Recent improvements, which were deduced from this findings, are presented: optimized PPVs with a lower amount of defects result in a strong increase of operational lifetime.
Electro-Absorption Spectroscopy on Poly(Arylene Vinylene)s
Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals, 1992
We report spectrally resolved electroabsorption (EA) measurements on poly(arylene vinylene)s. The... more We report spectrally resolved electroabsorption (EA) measurements on poly(arylene vinylene)s. The materials poly(thienylene vinylene), PTV, and poly(p-phenylene vinylene), PPV, are particularly attactive as they can be prepared from soluble precursors which allow ready fabrication of films. The subsequent thermal conversion of the precursor yields samples with good optical and mechanical properties and environmental stability. Both materials give a strong electro-optic
Electro-Optic Spectroscopy of Poly(3-Octylthiophene)
Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals, 1994
Abstract Electric field induced changes in the optical properties of poly (3-octylthiophene) in t... more Abstract Electric field induced changes in the optical properties of poly (3-octylthiophene) in the spectral region of the lowest π-π* electronic transition are reported. The electroabsorption [EA] resembles the first energy derivative of the unperturbed spectrum, scales quadratically with the applied electric field, and its lineshape is field invariant, all consistent with a DC Kerr effect whose origin is the Stark shift of a singlet exciton. In addition, a transition that does not appear in the unperturbed absorption spectrum is detected and ...
Spectroscopic investigation of the electro‐optic nonlinearity in poly(2,5‐thienylene vinylene)
Journal of Applied Physics, 1992
We report the results of a spectroscopic investigation of the quadratic electro‐optic nonlinearit... more We report the results of a spectroscopic investigation of the quadratic electro‐optic nonlinearity in poly(2,5‐thienylene vinylene). Electroabsorption spectra closely resemble the second energy derivative of the unperturbed π‐π* absorption and show oscillations associated with the strong vibronic features present therein. The dispersion of both the real and imaginary parts of χ(3) (−ω;0,0,ω) has been determined and we find that Re{χ(3)} has a peak value of 7.5×10−9 esu at 1.83 eV and Im{χ(3)} has a peak value of 6.2×10−9 esu at 1.78 eV. This nonlinearity is responsible for a photorefractive effect under resonant photoexcitation.
Large changes in optical response through chemical pre-ordering of poly(p-phenylenevinylene)
Advanced Materials, 1993
Halliday, DA, Burn, PL, Bradley, DDC, Friend, RH, Gelsen, OM, Holmes, AB, Kraft, A., Martens, JHF... more Halliday, DA, Burn, PL, Bradley, DDC, Friend, RH, Gelsen, OM, Holmes, AB, Kraft, A., Martens, JHF and Pichler, K.(1993), Large changes in optical response through chemical pre-ordering of poly (p-phenylenevinylene). Advanced Materials, 5: 4043. doi: 10.1002/ ...
computationally efficient methods. To address this, we have implemented a parallel Markov Chain M... more computationally efficient methods. To address this, we have implemented a parallel Markov Chain Monte Carlo scheme for sampling the posterior distribution.
ITE Technical Report, 1999
Las monografías originales remitidas para su publicación en esta colección deberán ser inéditas. ... more Las monografías originales remitidas para su publicación en esta colección deberán ser inéditas. El comité editorial, de acuerdo con la opinión del comité de redacción, decidirá sobre si procede o no la publicación, o bien propondrá modificaciones a los autores, notificándoles la fecha de admisión del trabajo. Los originales en castellano deberán llevar palabras clave y resumen en inglés. Deberán entregarse escritos en papel por duplicado y grabados en un disco de ordenador PC-compatible, de 3,5 (740 Kb) ó 5,25 pulgadas (360 Kb). El archivo en disco podrá corresponder a cualquiera de los siguientes formatos o programas: ASCII, DisplayWrite 4, DCA, RFT, Works, WordStar, WordPerfect, MS-Word, Multimate, XyWriter, PC-Tools, Ventura (indicar en la etiqueta del disco el procesador o formato empleado). Es preferible no incluir negrillas, cursivas, subrayados, paginación o cualquier otro tipo de formato en el documento grabado. No deben ponerse puntos y aparte vacíos para separar párrafos en el documento. En el texto que se entregará impreso en papel se incluirá un subrayado sencillo para los nombres de géneros y especies. Los apellidos de los autores citados en el texto se escribirán en MAYUSCULAS. La bibliografía irá al final del original y del archivo en disco, y deberá limitarse a los autores citados en el texto. Se dispondrán por orden alfabético de apellidos de autores citados y, dentro de cada autor, por orden cronológico. La referencia debe dar, por este orden, el apellido y a continuación las iniciales de los nombres propios del autor o autores, año de publicación, título completo del trabajo nombre de la revista, en abreviaturas usuales con subrayado sencillo, tomo y páginas primera y última. En el caso de libros se subrayará el título de los mismos y a continuación se pondrá la editorial, número de páginas y lugar de edición. Los esquemas y gráficos se realizarán con tinta china sobre papel vegetal en tamaño A4. Se incluirá escala gráfica si es necesario. Deberán llevar en el reverso escrito con lápiz el nombre del autor, número de orden y título resumido del trabajo. Los cuadros o tablas deberán ir numerados de forma independiente a los dibujos. En el archivo en disco, las columnas de las tablas o cuadros deberán separarse con un único tabulador entre cada dos columnas, y con punto y aparte al final de la última columna. En la copia en papel, las tablas y cuadros deberán tener el aspecto deseado. Los autores indicarán en el original el lugar en donde deben intercalarse las figuras y cuadros. Las leyendas de las figuras deberán ir en una hoja aparte, y después de la bibliografía en el documento en disco. Los autores recibirán un juego de pruebas de Imprenta para su corrección. Las modificaciones posteriores que se hicieran al texto original serán las de tipo gramatical o errores de impresión. Las correcciones que pudieran hacerse al texto del original serán con cargo a los autores. Las pruebas de imprenta deberán ser firmadas y devueltas en el plazo de quince días.
ITE Technical Report, 2000
Social acceptance and peer and romantic relationship self-efficacy were examined as salient facto... more Social acceptance and peer and romantic relationship self-efficacy were examined as salient factors related to social development among emerging adult (ages 18 to 25) survivors of pediatric cancers. Using a cross-sectional, within-groups methodology, relationships between cancer treatment intensity and peer and romantic relationship self-efficacy and social acceptance were assessed. Perceived health vulnerability, situational coping style, parent and peer attachment, and perceived physical attractiveness were explored as moderators of peer and romantic relationship self-efficacy and social acceptance. Additionally, social acceptance was examined within a cancer stereotyping framework. Fifty-two emerging adult survivors of pediatric cancers (54% male; mean (M) age = 21.38 years, standard deviation (SD) age = 3.11 years) completed self-report questionnaires. Participants were diagnosed between ages 5 and 19 (M age = 12.59 years, SD age = 4.57 years) and were at least six months post-active treatment (M time = 7.32 years, SD time = 4.46 years). Simultaneous regression analyses indicated that health vulnerability, coping style, parent and peer attachment, and physical attractiveness together accounted for a significant amount of variance in peer and romantic relationship self-efficacy and self-perceived social acceptance. There were significant main effects of perceptions of physical attractiveness and peer attachment on peer relationship self-efficacy and self-perceived social acceptance. There was also a main effect of perceived physical attractiveness on romantic relationship selfefficacy. However, treatment intensity was not significantly related to peer or romantic relationship self-efficacy or social acceptance. Furthermore, there were no significant moderating effects of health vulnerability, coping, parent or peer attachment, or physical attractiveness on the relationship between treatment intensity and peer or romantic relationship self-efficacy or social acceptance. In terms of social acceptance, participants believed that others" viewed them as more socially accepted than they viewed themselves. Participants also rated a hypothetical peer with cancer as less socially accepted than healthy peers. Results suggest greater perceived physical attractiveness and stronger attachment to peers may be strongly related to greater relationship confidence and feelings of being socially accepted. Survivors may also hold stereotyped views of their own level of social acceptance and the social acceptability of peers diagnosed with cancer. Future research and interventions implications are considered.
Le Journal de Physique Colloques, 1989
Resume : On decrit un appareil de diffusion qui perrnet 1'6tude des gels et des aerogels dans l a... more Resume : On decrit un appareil de diffusion qui perrnet 1'6tude des gels et des aerogels dans l a lumibre visible. Les formules permettant de corriger les resultats pour divers types de gbrn4ries sont explicitees. Nous reportons les resultats de diffusion obtenus pour des aerogels de silice ayant des densites de 71, 105 et 143 Kg/m3 ; les longueurs de correlation ac varient entre 10 et 25nm ; ces valeurs diminuent lorsque la densite augmente. Nous reportons aussi les resultats de diffusion de lumiere realises tors de la transformation sol-gel. Abstract -A scattering apparatus is described which allows the investigation of gels and aerogels with visible light. The correction formulas for various typical geometries are derived. Scattering data for silica aerogels with densities 71, 105 and 143 kg/mA3 are provided; the derived correlation lenghts a, are in the range 10 to 25 nm; they show a systematic decrease with increasing density. We also provide results for light scattering in a sol-gel process.
OLEDs & plastic electronics start to get serious
Speciality Chemicals, 2004
Comment on ‘‘Observation of the photorefractive effect in a polymer’’
Physical Review Letters, 1991
51.1: Invited Paper : Polymers for Efficient OLEDs
SID Symposium Digest of Technical Papers, 2000
Polymer light-emitting diodes (PLEDs) and displays based on polymer technology have made dramatic... more Polymer light-emitting diodes (PLEDs) and displays based on polymer technology have made dramatic progress during the last years. In particular, efficiency and device lifetime have improved to such a significant extent that first products will commercialized within this year. We report here on the technical status of materials and devices upon which this success is based. Efficiency and especially operational stability are now at a level which easily meets the requirements for a variety of applications, namely power efficiencies are well above 10 lm/W, operational lifetimes are exceeding 20000 hours at display brightness levels and room temperature). This progress has been achieved by the careful analysis of failure mechanisms and the systematic improvement of materials. The first products, i. e. back-lights (for LCD-displays), segmented displays, and finally passive-matrix-addressed low-information-content (LIC) graphical displays are described. Light emitting polymerss are now manufactured on industrial scale under high purity conditions; filling and packaging is done under a class 10 clean room condition. For details see H. Becker Paper 46.1.
Femtosecond Optical Absorption in Conjugated Polymers
Springer Series in Solid-State Sciences, 1992
We report transient absorption measurements using the pump and probe technique on poly(2,5 dimeth... more We report transient absorption measurements using the pump and probe technique on poly(2,5 dimethoxy-p-phenylene vinylene), DMPPV, and poly(p-phenylene vinylene), PPV. We observe a transient absorption in both materials, although a transient bleaching would be expected, and we discuss possible explanations for this behaviour.
Synthetic Metals, 2000
Ž .Ž. Poly p-phenylene vinylene s PPVs are promising materials for optoelectronic applications, e... more Ž .Ž. Poly p-phenylene vinylene s PPVs are promising materials for optoelectronic applications, especially for displays based on polymer Ž. light emitting diodes PLEDs. We report here our findings concerning defect structures in this class of materials and the implications of the discovered irregularities on important material properties, that is, the operational life in a PLED. Recent improvements, which were deduced from this findings, are presented: optimized PPVs with a lower amount of defects result in a strong increase of operational lifetime.
Electro-Absorption Spectroscopy on Poly(Arylene Vinylene)s
Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals, 1992
We report spectrally resolved electroabsorption (EA) measurements on poly(arylene vinylene)s. The... more We report spectrally resolved electroabsorption (EA) measurements on poly(arylene vinylene)s. The materials poly(thienylene vinylene), PTV, and poly(p-phenylene vinylene), PPV, are particularly attactive as they can be prepared from soluble precursors which allow ready fabrication of films. The subsequent thermal conversion of the precursor yields samples with good optical and mechanical properties and environmental stability. Both materials give a strong electro-optic
Electro-Optic Spectroscopy of Poly(3-Octylthiophene)
Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals, 1994
Abstract Electric field induced changes in the optical properties of poly (3-octylthiophene) in t... more Abstract Electric field induced changes in the optical properties of poly (3-octylthiophene) in the spectral region of the lowest π-π* electronic transition are reported. The electroabsorption [EA] resembles the first energy derivative of the unperturbed spectrum, scales quadratically with the applied electric field, and its lineshape is field invariant, all consistent with a DC Kerr effect whose origin is the Stark shift of a singlet exciton. In addition, a transition that does not appear in the unperturbed absorption spectrum is detected and ...
Spectroscopic investigation of the electro‐optic nonlinearity in poly(2,5‐thienylene vinylene)
Journal of Applied Physics, 1992
We report the results of a spectroscopic investigation of the quadratic electro‐optic nonlinearit... more We report the results of a spectroscopic investigation of the quadratic electro‐optic nonlinearity in poly(2,5‐thienylene vinylene). Electroabsorption spectra closely resemble the second energy derivative of the unperturbed π‐π* absorption and show oscillations associated with the strong vibronic features present therein. The dispersion of both the real and imaginary parts of χ(3) (−ω;0,0,ω) has been determined and we find that Re{χ(3)} has a peak value of 7.5×10−9 esu at 1.83 eV and Im{χ(3)} has a peak value of 6.2×10−9 esu at 1.78 eV. This nonlinearity is responsible for a photorefractive effect under resonant photoexcitation.
Large changes in optical response through chemical pre-ordering of poly(p-phenylenevinylene)
Advanced Materials, 1993
Halliday, DA, Burn, PL, Bradley, DDC, Friend, RH, Gelsen, OM, Holmes, AB, Kraft, A., Martens, JHF... more Halliday, DA, Burn, PL, Bradley, DDC, Friend, RH, Gelsen, OM, Holmes, AB, Kraft, A., Martens, JHF and Pichler, K.(1993), Large changes in optical response through chemical pre-ordering of poly (p-phenylenevinylene). Advanced Materials, 5: 4043. doi: 10.1002/ ...