Reduction of Quantum Noise in Transmittance Estimation Using PhotoneCorrelated Beams

The accuracy of optical measurements at low light levels is limited by the quantum noise of the source and by the random nature of the interaction with the measured object. The source noise may be reduced by use of nonclassical photon-number squeezed light. This paper considers the use of two photon-correlated beams (generated, for example, by spontaneous parametric downconversion) to measure the optical transmittance of an object. The photons of each beam obey a random Poisson process, but are synchronized in time. One beam is used to probe the object while the other is used as a reference providing information on the realization of the random arrival of photons at the object. The additional information available by such measurement may be exploited to improve the accuracy of the measurement. Various estimators, including the maximum likelihood estimator, are considered and their performance is evaluated and compared with the measurement based on single-beam conventional (Poisson) source and maximally squeezed (fixed photon number) source. The performance advantage established in this paper depends on parameters such as the intensity of the source, the transmittance of the object, the quantum efficiency of the detectors, the background noise, and the degree of correlation of the photon numbers in the two beams

Processing of nano-micro copper materials for the production of conductive circuits

Copper inks potentially provide a cost-effective alternative to silver for printed electronic circuits. In glass-based applications such as PV or smart glass, they can provide a means of conductivity enhancement or additional functionality. Three inks consisting of a mixture of nano and micro copper particles were systematically studied to examine the relationship between sintering temperature, sintering time and gaseous environment on the electrical qualities of the sintered printed films deposited on FTO coated glass. There is a definite interaction between the particulate nature of the ink, the sintering conditions, and the conductive properties of the film. Films containing only nano-particles provide the most conductive films with optimum sintering conditions of temperature of 225 °C for 60 minutes. The inclusion of micro particles increased the ideal sintering temperature but lowered the sintering time. An ink containing an equal mixture of nano and micro particles exhibited the lowest performance. This could be attributed to partial oxidation of the nano-particles along the conductive path, which occurs as a result of the presence of the micro particles. Other samples were photonically sintered using a PulseForge 1200 laboratory photonic sintering unit where the number of pulses, pulse power, pulse frequency and the intra pulse gap could be varied. An initial optimization study identified an operational range of photonic energy profile. The best possible line conductivity obtained using these optimum conditions was around a 1/3 of that obtained by conventional thermal sintering. This relative conductivity of photonically sintered features further deviated from conventionally sintered features as the film thickness increased and as the line width reduced. Laser / NIR techniques were found ineffective to sinter the copper ink used in this study. The possibility to manually blend copper and silver paste ink was investigated and an optimum blend of 25% silver and 75% copper could be used which had maintained conductivity, cost, and adhesion benefits

Kefaya – An Egyptian Movement for Change

KEFAYA is a word Egyptians might get accustomed to in the coming period. Everyone agrees that Reform is desirable and necessary, yet almost everyone disagrees about what should be reformed and how reform should occur. This paper deals more with domestic calls for reform, focusing on Gamal Mubarak as the bet of the Egyptian government and the Egyptian Movement for Change – a.k.a. KEFAYA - as the representative of other reform-seekers. Through comparing them both, the paper will assess which party intends or has better chances of achieving desired levels of reform

Urban detection, delimitation and morphology: comparative analysis of selective "megacities"

Postprint (published version

SECURITY AND PRIVACY ISSUES IN MOBILE NETWORKS, DIFFICULTIES AND SOLUTIONS

Mobile communication is playing a vital role in the daily life for the last two decades; in turn its fields gained the research attention, which led to the introduction of new technologies, services and applications. These new added facilities aimed to ease the connectivity and reachability; on the other hand, many security and privacy concerns were not taken into consideration. This opened the door for the malicious activities to threaten the deployed systems and caused vulnerabilities for users, translated in the loss of valuable data and major privacy invasions. Recently, many attempts have been carried out to handle these concerns, such as improving systems’ security and implementing different privacy enhancing mechanisms. This research addresses these problems and provides a mean to preserve privacy in particular. In this research, a detailed description and analysis of the current security and privacy situation in the deployed systems is given. As a result, the existing shortages within these systems are pointed out, to be mitigated in development. Finally a privacy preserving prototype model is proposed. This research has been conducted as an extensive literature review about the most relevant references and researches in the field, using the descriptive and evaluative research methodologies. The main security models, parameters, modules and protocols are presented, also a detailed description of privacy and its related arguments, dimensions and factors is given. The findings include that mobile networks’ security along with users are vulnerable due to the weaknesses of the key exchange procedures, the difficulties that face possession, repudiation, standardization, compatibility drawbacks and lack of configurability. It also includes the need to implement new mechanisms to protect security and preserve privacy, which include public key cryptography, HIP servers, IPSec, TLS, NAT and DTLS-SRTP. Last but not least, it shows that privacy is not absolute and it has many conflicts, also privacy requires sophisticated systems, which increase the load and cost of the system.fi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format

A Craniofacial Morphology Study Of Patients With Obstructive Sleep Apnea

Masalah tidur obstruktif apnea (OSA) didefinisikan sebagai pemberhentian pernafasan berulang (apneas) yang berlaku sekurang-kurangnya selama sepuluh saat atau lebih pada sesuatu ketika semasa tidur. Obstructive sleep apnea (OSA) is defined as a repetitive cessations of breathing (apneas) lasting for at least 10 seconds or more for each event during sleep

The Impact of Artificial Intelligence on the Graphic Design Industry

Artificial Intelligence (AI) is rapidly transforming many industries, including the field of graphic design. This paper aims to explore the impact of AI on graphic design and how it is shaping the future of the field. Through a literature review, we will examine how AI is being used in graphic design, including the automation of repetitive tasks, the generation of new design concepts, and the creation of personalized designs. We will also explore the potential benefits and drawbacks of AI in graphic design, such as increased efficiency and creativity, but also the loss of human touch and potential job displacement. Additionally, this paper will look at the ethical considerations surrounding the use of AI in graphic design and the implications it has on the industry. Overall, this paper will provide a comprehensive examination of the current state and future potential of AI in graphic design. Keywords: Artificial Intelligence, Graphic Design, Creativity, Technology, Machine Learning ,Design Industry. DOI: 10.7176/ADS/104-01 Publication date:March 31st 202