1,721,095 research outputs found
Synthesis and study of organic light emitting materials
© 2011 Dr. Inam ul Haq RajaSince the discovery of electroluminesence from organic materials, there has been a considerable amount of research, time and efforts devoted to developing conjugated materials as the active units in light emitting devices for use in display applications.
This thesis describes the synthesis and study of organic materials to achieve high efficiency in organic light emitting devices (OLEDs). A number of blue fluorescent and green to blue phosphorescent host polymers based on dibenzophosphole oxides have been synthesized and studied. Effect of the structure of polymer backbone and different substituents on optical properties has been studied and described. In addition, the synthesis and the study of polymers based on phosphine oxides have been described which are potential charge-transporting high triplet energy materials. All these polymers are thermally stable, blue fluorescent, potential hosts for green and blue phosphorescent guests and expected to facilitate charge transport in OLEDs
آئینہ ماہ و سال کے تخصیصی پہلو
The diverse experiences of life and the emotions related to it have been a central theme in literary works. Urdu literature is adorned with a variety of genres, among which autobiography holds significant prominence. The core and main focus of an autobiography centers on self-expression, allowing the author to shape his own portrait through his writings. Inam ul Haq Javed is a renowned scholar, literary critic, and linguist. He has written extensively on various aspects of Urdu literature, including poetry, fiction, autobiography and criticism. His works are known for his depth, insight, and thorough analysis, and have been widely acclaimed by scholars and literary circles.
As an autobiographer Inam-ul-Haq Javed enhances the charm of autobiography through detailed descriptions, vivid imagery, and the use of metaphors. His work "Aaina-e-Mah-o-Saal" fully adheres to the principles of autobiography. Undoubtedly, it holds a significant position in the tradition of autobiographical writing. In this article, we will explore the intellectual and artistic elements of "Aaina-e-Mah-o-Saal" within the context of the tradition of autobiography
L’analyse des textures dans la cadre LIP (Logarithmic Image Processing)
This thesis looks at the evaluation of textures in two different perspectives using logarithmic image processing (LIP) framework. The first case after introducing the concept of textures and giving some classical approaches of textures evaluation, it gives an original approach of textures evaluation called covariogram which is derived from similarity metrics like distances or correlations etc. The classical covariogram which is derived from the classical similarity metrics and LIP covariogram are then applied over several images and the efficiency of the LIP one is clearly shown for darkened images. The last two chapters offer a new approach by considering the gray levels of an image as the phases of a medium. Each phase simulates like a percolation of a liquid in a medium defining the percolation trajectories. The propagation from one pixel to another is taken as easy or difficult determined by the difference of the gray level intensities. Finally different parameters like fractality from fractal dimensions, mean histogram etc associated to these trajectories are derived, based on which the primary experiment for the classification of random texture is carried out determining the relevance of this idea. Obviously, our study is only first approach and requires additional workout to obtain a reliable method of classificationEn fait, le concept de texture n’est pas facile à définir, mais il est clair qu’il est fortement lié au Système Visuel Humain. Sachant que le Modèle LIP est compatible avec la vision humaine, il nous a semblé intéressant de créer des outils logarithmiques dédiés à l’évaluation de la texture. Nous nous sommes concentrés sur la notion de covariogramme, qui peut être pilotée par diverses métriques logarithmiques. Ces métriques jouent le rôle d’outils de “corrélation”, avec l’avantage de prendre en compte la vision humaine. De plus, les outils LIP sont peu dépendants des conditions d’éclairement et fournissent donc des résultats robustes si celles-ci varient. Les deux derniers Chapitres proposent une nouvelle approche consistant à considérer les niveaux de gris d’une image comme les phases d’un milieu. Chaque phase permet de simuler la percolation d’un liquide dans le milieu, définissant ainsi des trajectoires de percolation. Chaque propagation d’un pixel à un autre est considérée comme facile ou non, en fonction des niveaux de gris traversés. Une « fonction de coût » est créée, qui modifie le « temps » de propagation d’un point à l’autre. De plus, la fonction de coût peut être calculée dans le contexte LIP, pour prendre en compte la vision humain
The major security challenges to cloud computing.
Cloud computing is the computing model in which the computing resources such as software, hardware and data are delivered as a service through a web browser or light-weight desktop machine over the internet (Wink, 2012). This computing model abolishes the necessity of sustaining the computer resources locally hence cuts-off the cost of valuable resources (Moreno, Montero & Llorente, 2012). A distinctive cloud is affected by different security issues such as Temporary Denial of Service (TDOS) attacks, user identity theft, session hijacking issues and flashing attacks (Danish, 2011). The purpose of this study is to bridge the research gap between the cloud security measures and the existing security threats. An investigation into the existing cloud service models, security standards, currently adopted security measures and their degree of flawless protection has been done. The theoretical study helped in revealing the security issues and their solutions whereas the empirical study facilitated in acknowledging the concerns of users and security analysts in regards to those solution strategies. The empirical methods used in this research were interviews and questionnaires to validate the theoretical findings and to grasp the innovativeness of practitioners dealing with cloud security.With the help of theoretical and empirical research, the two-factor mechanism is proposed that can rule out the possibility of flashing attacks from remote location and can help in making the cloud components safer. The problem of junk traffic can be solved by configuring the routers to block junk data packets and extraneous queries at the cloud outer-border. This security measure is highly beneficial to cloud security because it offers a security mechanism at the outer boundary of a cloud. It was evaluated that a DOS attack can become a huge dilemma if it affects the routers and the effective isolation of router-to-router traffic will certainly diminish the threat of a DOS attack to routers. It is revealed that the data packets that require a session state on the cloud server should be treated separately and with extra security measures because the conventional security measures cannot perform an in-depth analysis of every data packet. This problem can be solved by setting an extra bit in the IP header of those packets that require a state and have a session. Although this change should be done at universal level and would take time; it can provide a protocol-independent way to identify packets which require extra care. It will also assist firewalls to drop bits which are requesting a session sate without a state-bit being set. The cloud security analysts should consider that the interface and authentication layer should not be merged into a single layer because it endangers the authentication system as the interface is already exposed to the world. The use of login-aiding devices along with secret keys can help in protecting the cloud users. Moreover, a new cloud service model “Dedicated cloud” is proposed in this research work to reinforce the cloud security. It was discovered that the optimal blend of HTTPS and SSL protocols can resolve the problem of session hijacks. The client interface area should be protected by HTTPS protocols and the secure cookies should be sent through a SSL link along with regular cookies. Disallowing the multiple sessions and the use of trusted IP address lists will help even further. A reasonable amount of care has been paid to ensure clarity, validity and trustworthiness in the research work to present a verifiable scientific knowledge in a more reader-friendly manner. These security guidelines will enhance the cloud security and make a cloud more responsive to security threats.Program: Masterutbildning i Informati
L’analyse des textures dans la cadre LIP (Logarithmic Image Processing)
This thesis looks at the evaluation of textures in two different perspectives using logarithmic image processing (LIP) framework. The first case after introducing the concept of textures and giving some classical approaches of textures evaluation, it gives an original approach of textures evaluation called covariogram which is derived from similarity metrics like distances or correlations etc. The classical covariogram which is derived from the classical similarity metrics and LIP covariogram are then applied over several images and the efficiency of the LIP one is clearly shown for darkened images. The last two chapters offer a new approach by considering the gray levels of an image as the phases of a medium. Each phase simulates like a percolation of a liquid in a medium defining the percolation trajectories. The propagation from one pixel to another is taken as easy or difficult determined by the difference of the gray level intensities. Finally different parameters like fractality from fractal dimensions, mean histogram etc associated to these trajectories are derived, based on which the primary experiment for the classification of random texture is carried out determining the relevance of this idea. Obviously, our study is only first approach and requires additional workout to obtain a reliable method of classificationEn fait, le concept de texture n’est pas facile à définir, mais il est clair qu’il est fortement lié au Système Visuel Humain. Sachant que le Modèle LIP est compatible avec la vision humaine, il nous a semblé intéressant de créer des outils logarithmiques dédiés à l’évaluation de la texture. Nous nous sommes concentrés sur la notion de covariogramme, qui peut être pilotée par diverses métriques logarithmiques. Ces métriques jouent le rôle d’outils de “corrélation”, avec l’avantage de prendre en compte la vision humaine. De plus, les outils LIP sont peu dépendants des conditions d’éclairement et fournissent donc des résultats robustes si celles-ci varient. Les deux derniers Chapitres proposent une nouvelle approche consistant à considérer les niveaux de gris d’une image comme les phases d’un milieu. Chaque phase permet de simuler la percolation d’un liquide dans le milieu, définissant ainsi des trajectoires de percolation. Chaque propagation d’un pixel à un autre est considérée comme facile ou non, en fonction des niveaux de gris traversés. Une « fonction de coût » est créée, qui modifie le « temps » de propagation d’un point à l’autre. De plus, la fonction de coût peut être calculée dans le contexte LIP, pour prendre en compte la vision humain
دور المجتمع لحماية شرف الإنسان في ضوء السنة النبوية: The Role of Society in Preserving Human Dignity in the Light of the Prophetic Sunnah
In diverse societies, while individuals vary in temperament and needs, the fundamental human need for connection remains constant. Islam places a strong emphasis on exemplary conduct, including truthfulness, trustworthiness, and kind speech. The Quran describes the Prophet Muhammad (peace be upon him) as a model of such virtues, advocating gentle communication with the directive: "And speak to people good words." His teachings underscore ideal behavior, such as compassion and avoiding insults. Islam encourages moderation in conflicts, condemns partisanship, and upholds justice while discouraging mockery and disparagement. Partisanship undermines justice and unity, and Islamic texts promote fairness and empathy over bias. Good manners and kind interactions are seen as vital for piety and divine blessings, fostering equality and preventing discrimination. The principle of defending one's honor in Islam aligns with maintaining positive interactions and avoiding public shame. Rooted in the Prophet Muhammad’s teachings, this principle highlights the importance of concealing personal faults and offering private counsel instead of publicizing sins. The Prophet emphasized protecting individual dignity and ensuring that public interventions are managed by appropriate authorities. Unjustly revealing faults is likened to consuming the flesh of a dead brother, a grievous act in Islam. Defending others' honor against unjust accusations is considered meritorious, reflecting Islam’s commitment to personal dignity and communal righteousness
WIRELESS SENSOR NETWORK PERFORMANCE IN HIGH VOLTAGE AND HARSH INDUSTRIAL ENVIRONMENTS
The applications of wireless sensor networks, WSN, are getting popular in the different areas reaching from daily usage to industrial usage. The performance evaluation of WSN deployed in industrial and high-voltage areas is receiving a great attention and becoming an interesting area of research. This thesis addresses the performance issues of WSN in high-voltage and harsh industrial environments. This study has been carried out at the facilities of High Voltage Test Lab of ABB. Typically, wireless sensor network contains wireless field devices (nodes) connected to a base station via a central gateway. The gate way centralizes information gathered and processed by the nodes. The nodes can communicate with each other and with the gateway via radio wave. The quality and usability of the data sent by WSN can be degraded due to the packet loss and delay. In the presence of high-voltage, the electromagnetic interference, EMI, can affect the performance of WSN. In this study the performance of WSN is evaluated in terms of packet loss and delay. We also focus on the effect of EMI on hardware devices as well as on signal transmission. EMI was expected at wide frequency band due to harsh industrial and high voltage environments. It was expected that EMIs could increase a bit error rate and/or packet loss. The EMI can also change the sensitivity of the nodes. For the performance evaluation of WSN network throughput, latency, path stability, data reliability and average value of the received signal strength indicator, RSSI, are used and measured. The results show that the electromagnetic frequencies of harsh industrial and high voltage environments affect the wireless sensor network performance.004670037521
L’analyse des textures dans la cadre LIP (Logarithmic Image Processing)
This thesis looks at the evaluation of textures in two different perspectives using logarithmic image processing (LIP) framework. The first case after introducing the concept of textures and giving some classical approaches of textures evaluation, it gives an original approach of textures evaluation called covariogram which is derived from similarity metrics like distances or correlations etc. The classical covariogram which is derived from the classical similarity metrics and LIP covariogram are then applied over several images and the efficiency of the LIP one is clearly shown for darkened images. The last two chapters offer a new approach by considering the gray levels of an image as the phases of a medium. Each phase simulates like a percolation of a liquid in a medium defining the percolation trajectories. The propagation from one pixel to another is taken as easy or difficult determined by the difference of the gray level intensities. Finally different parameters like fractality from fractal dimensions, mean histogram etc associated to these trajectories are derived, based on which the primary experiment for the classification of random texture is carried out determining the relevance of this idea. Obviously, our study is only first approach and requires additional workout to obtain a reliable method of classificationEn fait, le concept de texture n’est pas facile à définir, mais il est clair qu’il est fortement lié au Système Visuel Humain. Sachant que le Modèle LIP est compatible avec la vision humaine, il nous a semblé intéressant de créer des outils logarithmiques dédiés à l’évaluation de la texture. Nous nous sommes concentrés sur la notion de covariogramme, qui peut être pilotée par diverses métriques logarithmiques. Ces métriques jouent le rôle d’outils de “corrélation”, avec l’avantage de prendre en compte la vision humaine. De plus, les outils LIP sont peu dépendants des conditions d’éclairement et fournissent donc des résultats robustes si celles-ci varient. Les deux derniers Chapitres proposent une nouvelle approche consistant à considérer les niveaux de gris d’une image comme les phases d’un milieu. Chaque phase permet de simuler la percolation d’un liquide dans le milieu, définissant ainsi des trajectoires de percolation. Chaque propagation d’un pixel à un autre est considérée comme facile ou non, en fonction des niveaux de gris traversés. Une « fonction de coût » est créée, qui modifie le « temps » de propagation d’un point à l’autre. De plus, la fonction de coût peut être calculée dans le contexte LIP, pour prendre en compte la vision humain
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