Wyniki wyszukiwania - BazTech

1

Gaussian Approximation of Moments of Sums of Independent Random Variables

Lis M.

Bulletin of the Polish Academy of Sciences. Mathematics

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2012

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Vol. 60, no 1

77--90

EN

We continue the research of Latała on improving estimates of the pth moments of sums of independent random variables with logarithmically concave tails. We generalize some of his results in the case of 2≤p≤4 and present a combinatorial approach for even moments.

2

Analysis of loss and single-modality of thermally diffused areas in spliced joints of single mode telecommunication fibers

Ratuszek M., Zakrzewski Z., Majewski J., Ratuszek M.

Zeszyty Naukowe. Telekomunikacja i Elektronika / Uniwersytet Technologiczno-Przyrodniczy w Bydgoszczy

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2011

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z. 14

33-45

EN

In this work diffusion processes in thermally connected cylindrical fibers with weakly guiding and circular cross-section, that is telecommunication fibers, have been presented. There have been discussed diffusion distributions of the core dopant of fibers spliced in . Gaussian approximations of the core dopant concentration distribution and refractive index in the connecting area of single mode telecommunication fibers have been presented. Theoretical analysis of propagation and loss characteristics for thermally diffused expanded-core (TEC) of single mode telecommunication fibers has been performed, as well. It has been shown that because Gaussian profile approximates well diffusion distribution, this thermally diffused core area (splice) remains single-modal.

PL

W pracy przedstawiono procesy dyfuzji zachodzące w termicznie łączonych jedno-modowych włóknach o słabym prowadzeniu i przekroju kołowym, tj. jednomodowych światłowodach telekomunikacyjnych. Przeanalizowano dyfuzyjne rozkłady koncentracji domieszek rdzeniowych w tychże światłowodach spawanych w temperaturze . Zaprezentowano gaussowskie aproksymacje rozkładów koncentracji domieszek rdzeniowych oraz współczynnika załamania w obszarze łączenia włókien. Przeprowadzono teoretyczną analizę propagacji i tłumienia światła w termicznie rozdyfundowanych obszarach rdzeni (TEC) jednomodowych światłowodów telekomunikacyjnych. Wykazano, że ponieważ profil gaussowski dobrze aproksymuje rozkład dyfuzyjny domieszki rdzeniowej to rozdyfundowany obszar rdzenia (spawu) pozostaje jednomodowy po dyfuzji - procesie termicznego łączenia.

3

Loss analysis of single mode telecommunication fiber thermally-diffused core areas.

Ratuszek M.

Optica Applicata

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2007

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Vol. 37, nr 3

279-294

EN

In this work, diffusion processes in thermally connected cylindrical fibers with weakly guiding and circular cross-section, that is, telecommunication fibers, have been presented. There have been discussed diffusion distributions of the core dopant of fibers spliced at T 2000 deg. C. Gaussian approximations of the core dopant concentration distribution and refractive index in the connecting area of single mode telecommunication fibers have been presented. Theoretical analysis of propagation and loss characteristics for thermally-diffused expanded core (TEC) of single mode telecommunication fibers has been performed, as well. Consistence of theoretical calculation results with experimental data, achieved on the basis of connecting telecommunication fibers with significantly different parameters, has been proved.

4

Depth object recovery using a light line and a regression neural network

Muňoz Rodriguez J. A., Rodriguez-Vera R., Asundi A.

Optica Applicata

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2005

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Vol. 35, nr 2

295-309

EN

A technique for measuring the objects shape is presented. In this technique, the object is scanned using a light line. From the scanning a set of images is captured by a CCD camera. By processing these images, the object surface is recovered. To determine the surface dimensions, a regression neural network is applied. This network is built using data from images of a light line projected onto the objects, with known dimensions. The data are extracted from the images by applying Gaussian approximation. By using the neural network in this technique, the surface measurement is determined without using the parameters of the set-up. It improves the accuracy of the techniques of light line projection for shape detection, because errors of parameters of the set-up are not introduced to the system. This technique is tested in an experimental way and its results are verified with a contact method.