Wyniki wyszukiwania - BazTech

1

Introduction to coastal HF maritime surveillance radars

Ilcev Dimov Stojce

Polish Maritime Research

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2019

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nr 3

153--162

EN

This paper presents the main technical characteristics and working performances of coastal maritime surveillance radars, such as low-power High-Frequency Surface Wave Radars (HFSWR) and Over the Horizon Radars (OTHR). These radars have demonstrated to be a cost-effective long-range early-warning sensor for ship detection and tracking in coastal waters, sea channels and passages. In this work, multi-target tracking and data fusion techniques are applied to live-recorded data from a network of oceanographic HFSWR stations installed in Jindalee Operational Radar Network (JORN), Wellen Radar (WERA) in Ligurian Sea (Mediterranean Sea), CODAR Ocean Sebsorsin and in the German Bight (North Sea). The coastal Imaging Sciences Research (ISR) HFSWR system, Multi-static ISR HF Radar, Ship Classification using Multi-Frequency HF Radar, Coastal HF radar surveillance of pirate boats and Different projects of coastal HF radars for vessels detecting are described. Ship reports from the Automatic Identification System (AIS), recorded from both coastal and satellite Land Earth Stations (LES) are exploited as ground truth information and a methodology is applied to classify the fused tracks and to estimate system performances. Experimental results for all above solutions are presented and discussed, together with an outline for future integration and infrastructures.

2

The development of an underwater telephone for digital communication purposes

Schmidt J.

Hydroacoustics

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2016

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Vol. 19

341--352

EN

The underwater telephone HTL-10 has been designed to provide voice and data communication between helicopter and submarines using acoustic waves. It works in a halfduplex mode and uses analogue power-efficient modulation in the form of a single side-band, suppressed carrier, in a wide range of frequencies. It generates the transmitted signal, and processes the received signals. It is implemented with the use of digital signal processing techniques. Although it was designed several years ago, the flexible structure of the underwater telephone ensures a convenient platform for the implementation of various types of communication, as well as testing. This ability is due to the particular characteristics of the digital signal-processing module, which was designed by the author, both in hardware and software. The main elements of the module consist of the fixed-point signal processor, and the floating-point high performance digital signal processor. The article demonstrates the ability to adapt HTL-10 to implement digital communication in shallow waters, with a robust low data rate spread spectrum approach.

3

High-performance IR detectors at SCD present and future

Nesher O., Klipstein P. C.

Opto-Electronics Review

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2006

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Vol. 14, No. 1

61-70

EN

For over 27 years, SCD has been manufacturing and developing a wide range of high performance infrared detectors, designed to operate in either the mid-wave (MWIR) or the long-wave (LWIR) atmospheric windows. These detectors have been integrated successfully into many different types of system including missile seekers, time delay integration scanning systems, hand-held cameras, missile warning systems and many others. SCD's technology for the MWIR wavelength range is based on its well established 2D arrays of InSb photodiodes. The arrays are flip-chip bonded to SCD's analogue or digital signal processors, all of which have been designed in-house. The 2D focal plane array (FPA) detectors have a format of 320×256 elements for a 30-µm pitch and 480×384 or 640×512 elements for a 20-µm pitch. Typical operating temperatures are around 77–85 K. Five years ago SCD began to develop a new generation of MWIR detectors based on the epitaxial growth of antimonide based compound semiconductors (ABCS). This ABCS technology allows band-gap engineering of the detection material which enables higher operating temperatures and multi-spectral detection. This year SCD presented its first prototype FPA from this program, an InAlSb based detector operating at a temperature of 100 K. By the end of this year SCD will introduce the first prototype MWIR detector with a 640×512 element format and a pitch of 15 µm. For the LWIR wavelength range SCD manufactures both linear Hg1–xCdxTe (MCT) detectors with a line of 250 elements and time delay and integration (TDI) detectors with formats of 288×4 and 480×6. Recently, SCD has demonstrated its first prototype uncooled detector which is based on VOx technology and which has a format of 384×288 elements, a pitch of 25 µm, and a typical NETD of 50 mK at F/1. In this paper, we describe the present technologies and products of SCD and the future evolution of our detectors for the MWIR and LWIR detection.

4

Badanie dyfuzji leków w membranach koloidowych metodami spektroskopowymi

Bodzenta J., Hanh B., Kaźmierczak A., Neubert R., Wartewig S.

Zeszyty Naukowe. Matematyka - Fizyka / Politechnika Śląska

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2004

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z. 91

137-149

PL

W pracy przedstawiono wyniki dotyczące dyfuzji leków w sztucznych dodekanolowych membranach koloidowych (DDC), otrzymane metodami spektroskopowymi. Pomiary wykonano wykorzystując spektrometr IFS 28 firmy Bruker dla różnych konfiguracji układów detekcyjnych. Analizę transportu ketoconazolu przeprowadzono metodą fourierowskiej spektroskopii w podczerwieni z detekcją fotoakustyczną (FTIR-PAS). W przypadku dithranolu w pomiarach spektroskopowych zastosowano detekcję wykorzystującą tłumione całkowite wewnętrzne odbicie (FTIR-ATR). Do analizy danych eksperymentalnych wykorzystano model teoretyczny, w którym założono, że układ składał się z trzech warstw: źródła dyfuzji, membrany i warstwy powietrza. Rozkład przestrzenny koncentracji leku wyznaczono na podstawie drugiego prawa Ficka. Analizę wyników eksperymentalnych przeprowadzono dla wybranych linii widmowych, charakterystycznych dla badanego leku. Współczynnik dyfuzji wyznaczono na podstawie dopasowania krzywych teoretycznych do wyników eksperymentalnych.

EN

Results obtained from spectroscopic methods drugs diffusion into dodecanol-collodion membranę (DDC) are presented in this work. Experiment was carried out using IFS 28 Bruker spectrometer with different configuration of detection system. Fourier 1 transform infrared photoacoustic (FTIR-PAS) and Fourier transform infrared attenuated total reflectance (FTIR-ATR) techniques were applied to analysis of dithranol and ketoconazole penetration into artificial membranes. It was assumed that analyzed system consisted of three layers: the source of diffusion, the membrane and the air above it. The problem of spatial and time dependent distribution of a drug was solved based on Fick's second law. Analysis of experimental data was carried out for selected spectral line, characteristic for particular drug. The diffusion coefficient was determined from fitting theoretical curves to experimental results.