Σκοπός αυτής της διπλωματικής είναι η μελέτη, σχεδίαση και εξομοίωση κεραιών σχισμής τα χαρακτηριστικά των οποίων τις καθιστούν κατάλληλες για φορητές τερματικές συσκευές. Στο πρώτο κεφάλαιο γίνεται μια σύντομη αναφορά σε βασικές έννοιες της θεωρίας κεραιών, στις ηλεκτρικά μικρές κεραίες αλλά και στην αρχή του Babinet. Στόχος αυτού του κεφαλαίου είναι να συμβάλλει στην καλύτερη κατανόηση του περιεχομένου των επόμενων κεφαλαίων. Στο δεύτερο κεφάλαιο παρατίθενται κάποιες από τις πιο ευρέως διαδεδομένες υπάρχουσες γεωμετρίες κεραιών σχισμής, οι οποίες κατηγοριοποιούνται κυρίως ως προς το εύρος του φάσματος λειτουργίας τους. Στο τρίτο κεφάλαιο μελετάται μια βασική κεραία σχισμής, η κεραία ορθογώνιας σχισμής με τροφοδοσία συνεπίπεδου κυματοδηγού αλλά και μια πολύ ενδιαφέρουσα παραλλαγή της η οποία περιλαμβάνει ένα ζεύγος ορθογώνιων παρασιτικών στοιχείων. Στο τέταρτο κεφάλαιο μελετώνται οι κεραίες σχισμής μονής ζώνης λειτουργίας. Στα πλαίσια αυτής της μελέτης παρουσιάζονται συγκριτικά τα αποτελέσματα από τη σχεδίαση και εξομοίωση μιας κεραίας ζεύγους σχισμών σχήματος δακτυλίου και σχήματος κύκλου αντίστοιχα. Στο πέμπτο κεφάλαιο μελετώνται οι κεραίες σχισμής διπλής ζώνης λειτουργίας. Για το σκοπό αυτό σχεδιάστηκαν και εξομοιώθηκαν μια κεραία ζεύγους σχισμών σχήματος μονόπολου και μια κεραία σχισμής σχήματος βρόχου. Το περιεχόμενο του έκτου κεφαλαίου είναι η ανάλυση της συμπεριφοράς των κεραιών σχισμής ευρυζωνικής λειτουργίας. Αυτό επιτυγχάνεται μέσα από την μελέτη μιας κεραίας ρομβοειδούς σχισμής με ζεύγος μεταλλικών παρασιτικών στοιχειών, μια κεραία τοξοτής σχισμής καθώς και μια κεραία τριγωνικής σχισμής με ζεύγος τροφοδοσίας. Στο έβδομο κεφάλαιο μελετώνται οι υπερευρυζωνικές κεραίες σχισμής. Για το σκοπό αυτό σχεδιάστηκαν και εξομοιώθηκαν μια κεραία ελλειπτικής σχισμής με τροφοδοσία συνεπίπεδου κυματοδηγού και μια κεραίας ελλειπτικής σχισμής με στέλεχος προσαρμογής σχήματος U. Το όγδοο κεφάλαιο που έχει ως στόχο την μελέτη των κεραιών σχισμής που χρησιμοποιούνται σε χιλιοστομετρικές εφαρμογές περιλαμβάνει τα αποτελέσματα της σχεδίασης και εξομοίωσης μιας κεραίας κυκλικής σχισμής με τροφοδοσία μικροταινιακής γραμμής μεταφοράς. Τέλος στο ένατο κεφάλαιο γίνεται μια συνοπτική παρουσίαση των αποτελεσμάτων και παρατίθενται συμπεράσματα και προτάσεις για μελλοντική ενασχόληση στην περιοχή των κεραιών σχισμής. / This diploma thesis includes the analysis, design and simulation of slot antennas for portable terminal devices. In this thesis is presented a variety of slot antennas including single and dual band slot antennas, wideband and ultra wideband antennas as well as slot antennas for millimetre-wave applications.

Medical devices processing images or audio or executing complex AI algorithms are able to run more efficiently and meet real time requirements if the parallelism in those algorithms is exploited. In this research a methodology is proposed to exploit the flexibility and short design cycle of FPGAs (Field Programmable Gate Arrays) in order to achieve this target. Hardware/software co-design and dynamic partitioning allow the optimization of the multiprocessor platform design parameters and software code targeting each core to meet real time constraints. This is practically demonstrated by building a real life driver vigilance monitoring system based on visual cues extraction and evaluation. The application drives the whole design process to prove its effectiveness. An algorithm was built to achieve the goal of detecting the eye state of the driver (open or closed) and it is applied on captured consecutive frames to evaluate the vigilance state of the driver. Vigilance state is measured depending on duration of eye closure. This video processing application is then targeted to run on a multi-core FPGA based processing platform using the proposed methodology. Results obtained were very good using the Grimace Face Database and when operating the system on one’s face. On operating the device, a false positive of eye closure must take place two consecutive times in order to get an alarm, which decreases the probability of failure. The timing analysis applied proved the importance of using the concept of parallelism to achieve performance constraints. FPGA technology proved to be a very powerful prototyping tool for complex multiprocessor systems design. The flexible FPGA technology coupled with hardware/software co-design provided means to explore the design space and reach decisions that satisfy the design constraints with minimum time investment and cost.

Medical devices processing images or audio or executing complex AI algorithms are able to run more efficiently and meet real time requirements if the parallelism in those algorithms is exploited. In this research a methodology is proposed to exploit the flexibility and short design cycle of FPGAs (Field Programmable Gate Arrays) in order to achieve this target. Hardware/software co-design and dynamic partitioning allow the optimization of the multiprocessor platform design parameters and software code targeting each core to meet real time constraints. This is practically demonstrated by building a real life driver vigilance monitoring system based on visual cues extraction and evaluation. The application drives the whole design process to prove its effectiveness. An algorithm was built to achieve the goal of detecting the eye state of the driver (open or closed) and it is applied on captured consecutive frames to evaluate the vigilance state of the driver. Vigilance state is measured depending on duration of eye closure. This video processing application is then targeted to run on a multi-core FPGA based processing platform using the proposed methodology. Results obtained were very good using the Grimace Face Database and when operating the system on one’s face. On operating the device, a false positive of eye closure must take place two consecutive times in order to get an alarm, which decreases the probability of failure. The timing analysis applied proved the importance of using the concept of parallelism to achieve performance constraints. FPGA technology proved to be a very powerful prototyping tool for complex multiprocessor systems design. The flexible FPGA technology coupled with hardware/software co-design provided means to explore the design space and reach decisions that satisfy the design constraints with minimum time investment and cost.

Σκοπός της εργασίας είναι η μελέτη των ηλεκτρικά μικρών επίπεδων μαιανδρικών κεραιών που λειτουργούν στη ζώνη συχνοτήτων 2.4 GHz, καθώς και συστήματα με μαιανδρικές κεραίες πολλαπλής ζώνης συχνοτήτων (επιπλέον ζώνες ενδιαφέροντος είναι η 1.8 και η 5.2 GHz). Πρόκειται για κεραίες με μεγάλο εύρος ζώνης γύρω από τη συχνότητα συντονισμού που χρησιμοποιούνται σε κινητά τερματικά, όπως κινητά τηλέφωνα και φορητοί υπολογιστές και παρουσιάζουν πολλά πλεονεκτήματα, με κυριότερα το χαμηλό κόστος, την ευκολία κατασκευής, το μικρό τους μέγεθος και τη δυνατότητα μαζικής παραγωγής. Συστήματα κεραιών πολλαπλής ζώνης συχνοτήτων είναι επίσης μια σύγχρονη τεχνολογική απαίτηση, καθώς υπάρχει ανάγκη για διασύνδεση διαφορετικών υπηρεσιών που λειτουργούν σε διαφορετικές περιοχές συχνοτήτων, ειδικά όσον αφορά στα ασύρματα τοπικά δίκτυα. / The purpose of this thesis is to study the behaviour of small electrical antennas formed in meander shape, which operate at the frequency of 2.4 GHz, and dual band system operating in the ISM band and the DECT band of 1.8 GHz. These types of antennas present a large bandwidth around the resonant frequency and have great benefits, such as small dimensions and great efficiency at resonance.

Submitted by Arilson José de Oliveira Júnior null (arilsonjr@outlook.com) on 2016-09-23T17:30:32Z No. of bitstreams: 1 dissertação-v.16_final.pdf: 5639185 bytes, checksum: 41dab40b84e40ca63b845dee1590104f (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-09-27T18:21:10Z (GMT) No. of bitstreams: 1 oliveirajunior_ajo_me_bot.pdf: 5639185 bytes, checksum: 41dab40b84e40ca63b845dee1590104f (MD5) / Made available in DSpace on 2016-09-27T18:21:10Z (GMT). No. of bitstreams: 1 oliveirajunior_ajo_me_bot.pdf: 5639185 bytes, checksum: 41dab40b84e40ca63b845dee1590104f (MD5) Previous issue date: 2016-07-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Nos países de clima tropical, como o Brasil, um dos maiores desafios para produção animal e trabalho humano são os fatores ambientais, como altas temperaturas e umidades dentro de ambientes, assim como as tipologias das instalações, muitas vezes limitantes para o desempenho produtivo. O conforto térmico e a ambiência são áreas de estudo que tem por objetivo conceder o bem-estar para indivíduos, sejam eles animais ou seres humanos. Nos dias atuais grande parte das análises de conforto térmico no meio agrícola, ressaltando às em ambientes de produção animal, utilizam índices que possibilitam a avaliação do nível de estresse térmico de um determinado local por meio de variáveis climatológicas, como o Índice de Temperatura e Umidade – ITU, Índice de Temperatura de Globo Negro e Umidade – ITGU e Índice de Temperatura Equivalente – ITEq. Semelhantemente, em locais de trabalho humano há um limite de tolerância para exposição ao calor que deve ser monitorado mediante o chamado Índice de Bulbo Úmido Termômetro de Globo – IBUTG. Para a resolução desses índices, não há atualmente um sistema computacional específico, de hardware e software, que forneça, em tempo real, a condição térmica de um ambiente. Deste modo, o presente trabalho teve por objetivo desenvolver um sistema computacional capaz de avaliar, em tempo real, o conforto térmico de instalações de produção animal e de ambientes de trabalho humano. O sistema foi desenvolvido baseado na criação de um dispositivo portátil para coleta e transmissão das variáveis climatológicas de temperatura do ar, temperatura de globo negro e umidade relativa do ar, e do desenvolvimento de um aplicativo para smartphones e tablets Android. O dispositivo portátil foi desenvolvido utilizando um microcontrolador padrão Arduino, juntamente com sensores de temperatura e umidade relativa do ar. Para o desenvolvimento do aplicativo para dispositivos móveis, foi utilizado a linguagem de programação orientada a objetos Java no ambiente de desenvolvimento integrado Android Studio. O aplicativo para dispositivos móveis e o dispositivo portátil foram aplicados em diferentes ambientes e apresentaram correta medição de variáveis climatológicas e cálculo dos índices de conforto térmico. O dispositivo portátil demonstrou ser um produto funcional na transmissão de dados para dispositivos móveis. / In tropical weather countries, such as Brazil, one of the greatest challenges for animal production and human work environments are environmental factors, among them high temperature and humidity inside of the environments, as well as the type of facilities which are limiting for productive performance. The thermal comfort and the ambience are study areas that aims the well-being of individuals, whether they are animals or humans. It is possible to define thermal comfort as the pleasant thermal sensation of the body, in which are not necessary physiological efforts to keep the body in thermal balance. Nowadays, several analysis of thermal comfort in the agriculture environment, mainly at environments of animal production, apply indexes to make it possible the evaluation of thermal stress level of a specific place through the climatological variables, for instance, the Temperature and Humidity Index – THI, Black Globe-Humidity Index – BGHI and Heat Load Index – HLI. In the same way, at places of human work, there is a tolerance limit for heat exposition that should be monitored by the known Wet-bulb Globe Temperature Index – WBGT index. Currently, for resolution of these indexes, there is not a specific computational system (hardware and software) that provides the thermal comfort of an environment in real time. Therefore, the present work aimed to develop a computational system with features to evaluate in real time the thermal comfort of facilities of animal production and human work. The system was developed based on the creation of a mobile device to collect and transmit weather variables from the air temperature, black globe temperature and relative air humidity, and also the development of an app for smartphones and tablets. The mobile device was developed using the Arduino microcontroller, along with sensors of air temperature and relative humidity. For the development of the app it was used the Java oriented object program language, with the Android integrated development environment. The app for mobile devices and the portable device were applied in different environments and both presented a correctly measurement of climatological variables and the calculating of thermal comfort indexes. The portable device proved to be a functional product in data transmission for mobile devices.

O presente estudo investiga a escuta musical de nove jovens, com idade entre 14 e 20 anos, considerando suas vivências musicais e aprendizagens mediadas pelos dispositivos portáteis. A pesquisa teve como objetivo central identificar o potencial educativo da escuta musical dos jovens, por meio das tecnologias portáteis do formato de mp3. O referencial teórico foi construído a partir de três eixos: o primeiro, desenvolve o conceito de escuta musical, destacando as tipologias dos modos de escuta (IAZZETTA 2009, STOCKFELT, 2009). O segundo eixo refere-se às perspectivas teóricas da sociologia da música de Bull (2000), Thibaud (1992, 2003), Green (2004), Williams (2007), Pecqueux (2009a; 2009b), Granjon e Combes (2009) sobre as experiências auditivas na vida cotidiana contemporânea, bem como, DeNora (2000) com investigações sobre a forma como as pessoas incorporam a música no dia a dia. O terceiro eixo teórico está situado no campo da educação pelas mídias, focando os meios de comunicação, aprendizagem musical e juventude. Nesta perspectiva, os desenvolvimentos das diversas mídias são analisados numa visão mais ampla, enfatizando a flexibilidade, as múltiplas funções e a acessibilidade (KLÜBER 2003; SCHLÄBITZ 1997; MORDUCHOWICZ, 2008), assim como as abordagens que tratam o tema mídia e aprendizagem musical, como Souza (2004; 2011). A partir das perspectivas teóricas de Passeron e Revel (2005) e Leplat (2002), a metodologia adotada foi o estudo de caso. A análise dos dados revelou que a escuta portátil contribui para a construção de conhecimentos musicais. A escuta portátil fornece à aprendizagem musical aspectos particulares: desconstrói a linearidade da apreciação, proporcionando ao ouvinte a diversidade de gêneros musicais que constituem as playlists; transforma “espaços sociais” em “espaços musicais” e de aprendizagem; transita entre escutar, avaliar, perceber e compor. O estudo contribui para um novo olhar sobre o uso destes aparelhos na escuta portátil de jovens, sugerindo aos educadores musicais a criação de novas metodologias, a partir da compreensão dos procedimentos envolvidos nesta escuta. / The present study investigated the music listening habits of nine youngsters aged between 14 and 20 years, by considering their musical experiences and learning by the use of portable devices. The main focus was to identify the educational potential of music listening in youth, mediated by portable MP3 player technology. The theoretical framework was developed along three axes. The first axis is based on the concept of music listening, highlighting the types of listening modes (IAZZETTA 2009; STOCKFELT 2009). The second refers to the theoretical perspectives of Sociology of Music according to Bull (2000), Thibaud (1992, 2003), Green (2004), Williams (2007), Pecqueux (2009a; 2009b), and Granjon and Combes (2009), on the auditory experiences in contemporary everyday life, and also to DeNora (2000), on the investigations of how people incorporate the music in their daily activities. And the third axis is based on education through the media focusing on the means of communication, music learning and youth. In this perspective, the developments of various media are analyzed in a broader view, emphasizing the flexibility, the multiple functions and accessibility (KLÜBER 2003; SCHLÄBITZ 1997; MORDUCHOWICZ, 2008) as well as the studies that address the issue of media and music learning as did Souza (2004; 2011). This is a case study based on the theoretical perspectives of Passeron and Revel (2005) and Leplat (2002). The data analysis showed that the portable listening contributes to the construction of musical knowledge. Portable listening provides specific aspects to musical learning: it deconstructs the linearity of enjoyment, providing the listener with the diverse array of musical genres that make up the playlists; it turns the “social spaces” into “musical and learning spaces”; it passes through listening, evaluation, understanding and composing. The study allows a new look at the use of these devices in the portable listening of youth and suggests the creation of new methods based on the understanding of the procedures involved in this listening.

O presente estudo investiga a escuta musical de nove jovens, com idade entre 14 e 20 anos, considerando suas vivências musicais e aprendizagens mediadas pelos dispositivos portáteis. A pesquisa teve como objetivo central identificar o potencial educativo da escuta musical dos jovens, por meio das tecnologias portáteis do formato de mp3. O referencial teórico foi construído a partir de três eixos: o primeiro, desenvolve o conceito de escuta musical, destacando as tipologias dos modos de escuta (IAZZETTA 2009, STOCKFELT, 2009). O segundo eixo refere-se às perspectivas teóricas da sociologia da música de Bull (2000), Thibaud (1992, 2003), Green (2004), Williams (2007), Pecqueux (2009a; 2009b), Granjon e Combes (2009) sobre as experiências auditivas na vida cotidiana contemporânea, bem como, DeNora (2000) com investigações sobre a forma como as pessoas incorporam a música no dia a dia. O terceiro eixo teórico está situado no campo da educação pelas mídias, focando os meios de comunicação, aprendizagem musical e juventude. Nesta perspectiva, os desenvolvimentos das diversas mídias são analisados numa visão mais ampla, enfatizando a flexibilidade, as múltiplas funções e a acessibilidade (KLÜBER 2003; SCHLÄBITZ 1997; MORDUCHOWICZ, 2008), assim como as abordagens que tratam o tema mídia e aprendizagem musical, como Souza (2004; 2011). A partir das perspectivas teóricas de Passeron e Revel (2005) e Leplat (2002), a metodologia adotada foi o estudo de caso. A análise dos dados revelou que a escuta portátil contribui para a construção de conhecimentos musicais. A escuta portátil fornece à aprendizagem musical aspectos particulares: desconstrói a linearidade da apreciação, proporcionando ao ouvinte a diversidade de gêneros musicais que constituem as playlists; transforma “espaços sociais” em “espaços musicais” e de aprendizagem; transita entre escutar, avaliar, perceber e compor. O estudo contribui para um novo olhar sobre o uso destes aparelhos na escuta portátil de jovens, sugerindo aos educadores musicais a criação de novas metodologias, a partir da compreensão dos procedimentos envolvidos nesta escuta. / The present study investigated the music listening habits of nine youngsters aged between 14 and 20 years, by considering their musical experiences and learning by the use of portable devices. The main focus was to identify the educational potential of music listening in youth, mediated by portable MP3 player technology. The theoretical framework was developed along three axes. The first axis is based on the concept of music listening, highlighting the types of listening modes (IAZZETTA 2009; STOCKFELT 2009). The second refers to the theoretical perspectives of Sociology of Music according to Bull (2000), Thibaud (1992, 2003), Green (2004), Williams (2007), Pecqueux (2009a; 2009b), and Granjon and Combes (2009), on the auditory experiences in contemporary everyday life, and also to DeNora (2000), on the investigations of how people incorporate the music in their daily activities. And the third axis is based on education through the media focusing on the means of communication, music learning and youth. In this perspective, the developments of various media are analyzed in a broader view, emphasizing the flexibility, the multiple functions and accessibility (KLÜBER 2003; SCHLÄBITZ 1997; MORDUCHOWICZ, 2008) as well as the studies that address the issue of media and music learning as did Souza (2004; 2011). This is a case study based on the theoretical perspectives of Passeron and Revel (2005) and Leplat (2002). The data analysis showed that the portable listening contributes to the construction of musical knowledge. Portable listening provides specific aspects to musical learning: it deconstructs the linearity of enjoyment, providing the listener with the diverse array of musical genres that make up the playlists; it turns the “social spaces” into “musical and learning spaces”; it passes through listening, evaluation, understanding and composing. The study allows a new look at the use of these devices in the portable listening of youth and suggests the creation of new methods based on the understanding of the procedures involved in this listening.

O presente estudo investiga a escuta musical de nove jovens, com idade entre 14 e 20 anos, considerando suas vivências musicais e aprendizagens mediadas pelos dispositivos portáteis. A pesquisa teve como objetivo central identificar o potencial educativo da escuta musical dos jovens, por meio das tecnologias portáteis do formato de mp3. O referencial teórico foi construído a partir de três eixos: o primeiro, desenvolve o conceito de escuta musical, destacando as tipologias dos modos de escuta (IAZZETTA 2009, STOCKFELT, 2009). O segundo eixo refere-se às perspectivas teóricas da sociologia da música de Bull (2000), Thibaud (1992, 2003), Green (2004), Williams (2007), Pecqueux (2009a; 2009b), Granjon e Combes (2009) sobre as experiências auditivas na vida cotidiana contemporânea, bem como, DeNora (2000) com investigações sobre a forma como as pessoas incorporam a música no dia a dia. O terceiro eixo teórico está situado no campo da educação pelas mídias, focando os meios de comunicação, aprendizagem musical e juventude. Nesta perspectiva, os desenvolvimentos das diversas mídias são analisados numa visão mais ampla, enfatizando a flexibilidade, as múltiplas funções e a acessibilidade (KLÜBER 2003; SCHLÄBITZ 1997; MORDUCHOWICZ, 2008), assim como as abordagens que tratam o tema mídia e aprendizagem musical, como Souza (2004; 2011). A partir das perspectivas teóricas de Passeron e Revel (2005) e Leplat (2002), a metodologia adotada foi o estudo de caso. A análise dos dados revelou que a escuta portátil contribui para a construção de conhecimentos musicais. A escuta portátil fornece à aprendizagem musical aspectos particulares: desconstrói a linearidade da apreciação, proporcionando ao ouvinte a diversidade de gêneros musicais que constituem as playlists; transforma “espaços sociais” em “espaços musicais” e de aprendizagem; transita entre escutar, avaliar, perceber e compor. O estudo contribui para um novo olhar sobre o uso destes aparelhos na escuta portátil de jovens, sugerindo aos educadores musicais a criação de novas metodologias, a partir da compreensão dos procedimentos envolvidos nesta escuta. / The present study investigated the music listening habits of nine youngsters aged between 14 and 20 years, by considering their musical experiences and learning by the use of portable devices. The main focus was to identify the educational potential of music listening in youth, mediated by portable MP3 player technology. The theoretical framework was developed along three axes. The first axis is based on the concept of music listening, highlighting the types of listening modes (IAZZETTA 2009; STOCKFELT 2009). The second refers to the theoretical perspectives of Sociology of Music according to Bull (2000), Thibaud (1992, 2003), Green (2004), Williams (2007), Pecqueux (2009a; 2009b), and Granjon and Combes (2009), on the auditory experiences in contemporary everyday life, and also to DeNora (2000), on the investigations of how people incorporate the music in their daily activities. And the third axis is based on education through the media focusing on the means of communication, music learning and youth. In this perspective, the developments of various media are analyzed in a broader view, emphasizing the flexibility, the multiple functions and accessibility (KLÜBER 2003; SCHLÄBITZ 1997; MORDUCHOWICZ, 2008) as well as the studies that address the issue of media and music learning as did Souza (2004; 2011). This is a case study based on the theoretical perspectives of Passeron and Revel (2005) and Leplat (2002). The data analysis showed that the portable listening contributes to the construction of musical knowledge. Portable listening provides specific aspects to musical learning: it deconstructs the linearity of enjoyment, providing the listener with the diverse array of musical genres that make up the playlists; it turns the “social spaces” into “musical and learning spaces”; it passes through listening, evaluation, understanding and composing. The study allows a new look at the use of these devices in the portable listening of youth and suggests the creation of new methods based on the understanding of the procedures involved in this listening.

Portable, handheld, and wearable devices are an integrate part of everyday life, yet there is no well-established text inputmethod for devices with very small screens. Speech to text has been a quick fix, but entails privacy concerns and can beobtrusive. Chord keyboards bring various advantages for application in a mobile environment, as they require fewer keys andcan thus be small and portable. The aim of this work is to suggest an alternative to the QWERTY keyboard, suitable for textentry on devices of all sizes, shapes and mobility requirements. A one hand operational chord keyboard was developed andevaluated in a small user study with regard to its social acceptability. Learnability showed to be a concern that discouragesuse, while social aspects did not seem to be an issue.

Dihydro-1,2,4,5-tetrazine-3,6-dicarboxylate was introduced into the chemically stable UiO-66 structure by a postsynthetic linker exchange reaction to create an optical sensor material for the detection of oxidative agents such as nitrous gases. The incorporated tetrazine unit can be reversibly oxidized and reduced, which is accompanied by a drastic colour change from yellow to pink and vice versa. The high stability of the framework during redox reaction was proven by powder X-ray diffraction and nitrogen physisorption measurements.