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Abstract

The concept of “places of refuge ” comes from the Convention on Maritime Safety of 1989. The term “port of refuge” had emerged earlier in maritime practice. Resolution A.949/23/ o f the General Assembly of the IMO, from 5 December 2004, speaks of “places of refuge” for ships in need of help. Directive 2002/59/WE o f the European Parliament and Council, setting up a community system of monitoring and of information on the movement of vessels, and abrogating Council Directive 93/75/EWG, introduced places of refuge, drawing on the “Guidelines ” of the IMO. IMO Resolution A.949/23/ became the legal norm valid in Member States. The decree of the Polish Minister for Maritime Economy from 14 September 2007, as executive implementation of legislation of 20 April 2004, concerning a change of legislation in the matter of maritime safety, sets out a plan for offering refuge in Polish maritime waters to vessels that find themselves in danger. The author accepts that a place of refuge may be a natural spot that is appropriate for this purpose, and also a place specially constructed for vessels in danger. It may also be an existing port or part of one.
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Abstract

The author applies terminology and methods employed in legal theory (i.e. superflua, practical inconsistencies, legal gaps) to laws on protection o f marine environment. The central question is whether there is overabundance o f rules on the subject, including rules o f law, and whether such overabundance is detrimental. The problem is explicated by the case o f Dębki (Krokowa County), a remarkably beautiful marine ecosystem west of Władysławowo, where an initiative to construct 33 wind turbines towering 150 meters within 5 kilometers from the coastline evoked civil protests. The debate was sparked by a controversial decision o f 9 September 2009 by Regional Director for Environmental Protection. The author explores general issues of civic participation and property dispute in the context o f environmental protection.
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Abstract

Ultrasonic methods of human body internal structures imaging are being continuously enhanced. New algorithms are created to improve certain output parameters. A synthetic aperture method (SA) is an example which allows to display images at higher frame-rate than in case of conventional beam-forming method. Higher computational complexity is a limitation of SA method and it can prevent from obtaining a desired reconstruction time. This problem can be solved by neglecting a part of data. Obviously it implies a decrease of imaging quality, however a proper data reduction technique would minimize the image degradation. A proposed way of data reduction can be used with synthetic transmit aperture method (STA) and it bases on an assumption that a signal obtained from any pair of transducers is the same, no matter which transducer transmits and which receives. According to this postulate, nearly a half of the data can be ignored without image quality decrease. The presented results of simulations and measurements with use of wire and tissue phantom prove that the proposed data reduction technique reduces the amount of data to be processed by half, while maintaining resolution and allowing only a small decrease of SNR and contrast of resulting images.
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Abstract

A new ultrasound digital transcranial Doppler system (digiTDS) is introduced. The digiTDS enables diagnosis of intracranial vessels which are rather difficult to penetrate for standard systems. The device can display a color map of flow velocities (in time-depth domain) and a spectrogram of a Doppler signal obtained at particular depth. The system offers a multigate processing which allows to display a number of spectrograms simultaneously and to reconstruct a flow velocity profile. The digital signal processing in digiTDS is partitioned between hardware and software parts. The hardware part (based on FPGA) executes a signal demodulation and reduces data stream. The software part (PC) performs the Doppler processing and display tasks. The hardware-software partitioning allowed to build a flexible Doppler platform at a relatively low cost. The digiTDS design fulfills all necessary medical standards being a new useful tool in the transcranial field as well as in heart velocimetry research.
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Abstract

This paper presents the design and measurements of low-noise multichannel front-end electronics for recording extra-cellular neuronal signals using microelectrode arrays. The integrated circuit contains 64 readout channels and is fabricated in CMOS 180 nm technology. A single readout channel is built of an AC coupling circuit at the input, a low-noise preamplifier, a band-pass filter and a second amplifier. In order to reduce the number of output lines, the 64 analog signals from readout channels are multiplexed to a single output by an analog multiplexer. The chip is optimized for low noise and good matching performance and has the possibility of pass-band tuning. The low cut-off frequency can be tuned in the 1 Hz - 60 Hz range while the high cut-off frequency can be tuned in the 3.5 kHz - 15 kHz range. For the nominal gain setting at 44 dB and power dissipation per single channel of 220 μW, the equivalent input noise is in the range from 6 μV - 11 μV rms depending on the band-pass filter settings. The chip has good uniformity concerning the spread of its electrical parameters from channel to channel. The spread of the gain calculated as standard deviation to mean value is about 4.4% and the spread of the low cut-off frequency set at 1.6 Hz is only 0.07 Hz. The chip occupies 5×2.3 mm2 of silicon area. To our knowledge, our solution is the first reported multichannel recording system which allows to set in each recording channel the low cut-off frequency within a single Hz with a small spread of this parameter from channel to channel. The first recordings of action potentials from the thalamus of the rat under urethane anesthesia are presented.
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