Acceleration and Particle Field Interactions of Cosmic Rays I: Formalism

The acceleration of ultra high energy cosmic rays is conjectured to occur through various interactions with the electromagnetic fields in different astrophysical objects, like magnetic matter clumps, besides the well-known shock and stochastic Fermi mechanisms. It is apparent that the latter are not depending on the particle's charge, quantitatively. Based on this model, a considerable portion of the dynamics, that derives a charged particle parallel to a magnetic field $\mathbf{B}$ and under the influence of a force $\mathbf{F}$, is assumed to be composed of an acceleration by a non-magnetic force $\mathbf{F}_{\parallel}$ and a gyromotion along $\mathbf{B}$ direction, plus drifts in the direction of $\mathbf{F}_{\perp}$. The model and its formalism are introduced. Various examples for drift motions and accelerating forces are suggested. The formalism is given in a non-relativistic version. Obviously, the translation into the relativistic version is standard. In a forthcoming work, a quantitative estimation of the energy gained by charged cosmic rays in various astrophysical objects will be evaluated.Comment: 9 pages, 2 EPS figure

Role of entanglement in two-photon imaging

The use of entangled photons in an imaging system can exhibit effects that cannot be mimicked by any other two-photon source, whatever the strength of the correlations between the two photons. We consider a two-photon imaging system in which one photon is used to probe a remote (transmissive or scattering) object, while the other serves as a reference. We discuss the role of entanglement versus correlation in such a setting, and demonstrate that entanglement is a prerequisite for achieving distributed quantum imaging.Comment: 15 pages, 2 figure

Quantum entanglement distribution with 810 nm photons through telecom fibers

We demonstrate the distribution of polarization entangled photons of wavelength 810 nm through standard telecom fibers. This technique allows quantum communication protocols to be performed over established fiber infrastructure, and makes use of the smaller and better performing setups available around 800 nm, as compared to those which use telecom wavelengths around 1550 nm. We examine the excitation and subsequent quenching of higher-order spatial modes in telecom fibers up to 6 km in length, and perform a distribution of high quality entanglement (visibility 95.6%). Finally, we demonstrate quantum key distribution using entangled 810 nm photons over a 4.4 km long installed telecom fiber link.Comment: 5 pages, 5 figures, 1 tabl

Fast Iris Localization Based on Image Algebra and Morphological Operations

تحديد منطقة القزحية هي العملية الأكثر أهمية في نظام التعرف على القزحية التي تكون خاضعة وبشدة لتأثيرات البيئة,  وبالتالي، فقد تم اقتراح طريقة جديدة  لتحديد الحدود الداخلية والخارجية للقزحية. الفائدة الرئيسية من استخدام العمليات الحسابية للصور هي أنها طريقة بسيطة وسريعة وان هذه المميزات يتم استخدامها ودمجها مع العمليات المورفولوجية في تصميم الخوارزمية المقترحة. خوارزمية تحديد القزحية المقترحة قد صممت مع الأخذ بعين الاعتبار الملامح الشكلية لصورة قزحية العين مثل منطقة الضوضاء الموجودة في أجزاء مختلفة من صورة العين (مثل الانعكاسات الضوئية والتركيز والقزحية المرئية بصورة جزئية). النتائج التجريبية لتحديد القزحية تم إجراؤها على مجموعة من صور قزحية العين تتكون من 756 صورة تنتمي إلى قاعدة بيانات معهد العلوم الأكاديمي الصيني للأتمتة (CASIA V-1)، و450 صورة تنتمي إلى قاعدة بيانات جامعة الوسائط المتعددة (MMU V-1), تشير النتائج إلى تحقيق مستوى عالٍ من الدقة باستخدام التقنية المقترحة. علاوة على ذلك، فإن نتائج المقارنة مع خوارزميات تحديد القزحية الحديثة تعزز من دقة عملية فصل القزحية بشكل كبير اضافة الى كونها أكثر كفاءة من الناحية الحسابية.The localization of the iris is the most significant factor in biometrics of the iris, which traditionally assumes strictly controlled environments. The proposed method includes the pupillary and limbic iris boundaries localization. A primary advantage of image arithmetic operations is that the process is straightforward and therefore fast, these characteristics are employed and combined with the morphological operators in the designing of the proposed algorithm. The proposed algorithm takes into account the noise area which is found in various parts of the eye image such as light reflections, focus, and small visible iris. The experimental results are conducted on a collection of iris images consist of 756 images belong to Chinese Academy of Sciences Institute of Automation (CASIA V-1) and 450 images belong to Multi Media University (MMU V-1) databases.  The results indicate a high level of accuracy using the proposed technique. Moreover, the comparison results with the state-of-the-art iris localization algorithms expose considerable improvement in segmentation accuracy while being computationally more efficient

Quantum process tomography with coherent states

We develop an enhanced technique for characterizing quantum optical processes based on probing unknown quantum processes only with coherent states. Our method substantially improves the original proposal [M. Lobino et al., Science 322, 563 (2008)], which uses a filtered Glauber-Sudarshan decomposition to determine the effect of the process on an arbitrary state. We introduce a new relation between the action of a general quantum process on coherent state inputs and its action on an arbitrary quantum state. This relation eliminates the need to invoke the Glauber-Sudarshan representation for states; hence it dramatically simplifies the task of process identification and removes a potential source of error. The new relation also enables straightforward extensions of the method to multi-mode and non-trace-preserving processes. We illustrate our formalism with several examples, in which we derive analytic representations of several fundamental quantum optical processes in the Fock basis. In particular, we introduce photon-number cutoff as a reasonable physical resource limitation and address resource vs accuracy trade-off in practical applications. We show that the accuracy of process estimation scales inversely with the square root of photon-number cutoff.Comment: 18 pages, 2 figure

Studies of Salt Water intrusion in Opobo/Nkoro Rivers State Using Geophysical and Hydrochemical Methods

Salt water intrusions into fresh water aquifers in Opobo town in Nkoro L.G.A, Rivers state is becoming an issue of concern to the community, and as such requires detailed analysis through an integration of qualitative (geo-electric) and quantitative (hydrochemical) methods. Twenty vertical electrical soundings (VES) labelled as O/MSC/01 to O/MSC/20 and three 2D electrical resistivity tomography (ERT) data were acquired in the area. Results from interpretation of the twenty VES profiles showed 4 geo-electric layers, which are topsoil, sand, sandy clay and clay. In VES geo-electric sections, it was observed that salt intrusions occur at depths of 43.135m, 55.20m, 43.528m, 51.63m, and 28.357m along O/MSC/02, O/MSC/05, O/MSC/07, O/MSC/11 and O/MSC/15 profiles respectively. No salt intrusion was observed in O/MSC/01, O/MSC/04, O/MSC/09, O/MSC/10, O/MSC/12 and O/MSC/14 within the depth investigated. Results of 2D imaging along VES profiles 10, 11 and 12, show salt intrusions observed along the three profiles at different depths within the subsurface. Along profile O/MSC/10, saltwater intrusions (with resistivity range of 59.2Ωm-60.1Ωm) was observed at depth of 7.59-9.59m at lateral distance of 34.0-36.0m and depth of 5.59-7.59m at lateral distance of 94-96m. Along profile O/MSC/11 salt intrusions (with resistivity range of 58.8Ωm-59.2Ωm) was observed at depth of 2.59-5.59m at lateral distance of 28-40m, and 110-128m, while along profile O/MSC/12 salt intrusions (with resistivity range of 14.5-20Ωm) was observed at depth of 3.59-5.59m at lateral distance of 112-118m. These findings were not observed in VES surveys along similar profiles where 2D ERT was carried out. 3D map computed to connect aquifers within the third geo-electric layers for VES points 1-20, showed that within the third geo-electric layers for O/MSC/02, 05, 07, 11, 16, 17, and 20 lies saline water. The reliability of these results was validated by results from quantitative assessment of physiochemical parameters (PH, electrical conductivity (EC), and total hardness) and hydrochemical contents (HCO3-, Na+, K+, CL-, and SO42-) used to evaluate the ionic abundance of water samples taken from seven wells/boreholes in the area. PH values of 6.40-6.90 were predominant in the samples which indicates slight acidity and unsuitable for human consumption, EC values in the order of 1705μS/cm, & 1853.74μS/cm were obtained and total dissolved Solids (TDS) was in the order of 700.30mg/l & 750.02mg/l. Elevated EC values in water is indicative of high ionic abundance, and is diagnostic to salinity of the water as reflected in the 1D and 2D geo-electric surveys. However, the study area also contains fresh water aquifers lying within the third geo-electric layers for VES profiles O/MSC/01, 03, 06, 08, 09, 10, 12, and 18, hence a water supply tube well can be drilled in these areas for groundwater production but the water should be subjected to hydrochemical test to ascertain its level of contamination and prior treatments before human consumption. Keywords: Saltwater Intrusion, Groundwater, Vertical electrical sounding (VES), Electrical resistivity  tomography (ERT), Geo-electric section

Multi-directional maximum-entropy approach to the evolutionary design optimization of water distribution systems

A new multi-directional search approach that aims at maximizing the flow entropy of water distribution systems is investigated. The aim is to develop an efficient and practical maximum entropy based approach. The resulting optimization problem has four objectives, and the merits of objective reduction in the computational solution of the problem are investigated also. The relationship between statistical flow entropy and hydraulic reliability/failure tolerance is not monotonic. Consequently, a large number of maximum flow entropy solutions must be investigated to strike a balance between cost and hydraulic reliability. A multi-objective evolutionary optimization model is developed that generates simultaneously a wide range of maximum entropy values along with clusters of maximum and near-maximum entropy solutions. Results for a benchmark network and a real network in the literature are included that demonstrate the effectiveness of the procedure

Dispersive Optical Interface Based on Nanofiber-Trapped Atoms

We dispersively interface an ensemble of one thousand atoms trapped in the evanescent field surrounding a tapered optical nanofiber. This method relies on the azimuthally-asymmetric coupling of the ensemble with the evanescent field of an off-resonant probe beam, transmitted through the nanofiber. The resulting birefringence and dispersion are significant; we observe a phase shift per atom of $\sim$\,1\,mrad at a detuning of six times the natural linewidth, corresponding to an effective resonant optical density per atom of 0.027. Moreover, we utilize this strong dispersion to non-destructively determine the number of atoms.Comment: 4 pages, 4 figure