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Number of results: 47
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Abstract

We studied lateral silicon p-i-n junctions, doped with phosphorus and boron, regarding charge sensing feasibility. In order to examine the detection capabilities and underlying mechanism, we used in a complementary way two measurement techniques. First, we employed a semiconductor parameter analyzer to measure I−V characteristics at a low temperature, for reverse and forward bias conditions. In both regimes, we systematically detected Random Telegraph Signal. Secondly, using a Low Temperature Kelvin Probe Force Microscope, we measured surface electronic potentials. Both p-i-n junction interfaces, p-i and i-n, were observed as regions of a dynamic behaviour, with characteristic time-dependent electronic potential fluctuations. Those fluctuations are due to single charge capture/emission events. We found analytically that the obtained data could be explained by a model of two-dimensional p-n junction and phosphorus-boron interaction at the edge of depletion region. The results of complementary measurements and analysis presented in this research, supported also by the previous reports, provide fundamental insight into the charge sensing mechanism utilizing emergence of individual dopants.
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Abstract

A complex model of mechanically ventilated ARDS lungs is proposed in the paper. This analogue is based on a combination of four components that describe breathing mechanics: morphology, mechanical properties of surfactant, tissue and chest wall characteristics. Physical-mathematical formulas attained from experimental data have been translated into their electrical equivalents and implemented in MultiSim software. To examine the adequacy of the forward model to the properties and behaviour of mechanically ventilated lungs in patients with ARDS symptoms, several computer simulations have been performed and reported in the paper. Inhomogeneous characteristics observed in the physical properties of ARDS lungs were mapped in a multi-lobe model and the measured outputs were compared with the data from physiological reports. In this way clinicians and scientists can obtain the knowledge on the moment of airway zone reopening/closure expressed as a function of pressure, volume or even time. In the paper, these trends were assessed for inhomogeneous distributions (proper for ARDS) of surfactant properties and airway geometry in consecutive lung lobes. The proposed model enables monitoring of temporal alveolar dynamics in successive lobes as well as those occurring at a higher level of lung structure organization, i.e. in a point P0 which can be used for collection of respiratory data during indirect management of recruitment/de-recruitment processes in ARDS lungs. The complex model and synthetic data generated for various parametrization scenarios make possible prospective studies on designing an indirect mode of alveolar zone management, i.e. with
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Abstract

In the region of the Admiralty Bay 12 nesting bird species were encountered of a total abundance of 40890 pairs and biomass amounting to about 395000 kg Three penguin species constituted 91.7% in abundance, their biomass constituting 98.7% of the whole community. Densities of abundance and biomass of adult birds in relation to the living area of penguins (i.e. 775 km2) ranged from 32.3 to 121.4 indiv. km-2 and from 115.1 to 4730 kg k m-2.
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Abstract

Observations were carried out in Penguin Island on 27 January 1979. The results of the birds census were as follows: Pygoscelis adeliae— 1710 pairs, P. antarclica— 7058 pairs, Macronecles giganteus—512 pairs, Oceanites oceanicus — 47 pairs, Chionis alba — 5, Stercorarius skua lonnbergi — 6 pairs, Larus dominicanus — 63 pairs, Sterna vittata—18. Other species showed different requirements as regards breeding grounds. Simultaneously the following Pinnipedia were observed on Penguin Island: Mirounga leonina — 202 specimens, Arctocephalus gazella — 48 adult and 6 young individuals, Leptonychotes weddelli — 2, Lobodon carcinophagus — 1.
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Abstract

Bardzo często niepełnosprawność kojarzona jest z dysfunkcjami motorycznymi, podczas gdy dysfunkcje wzroku, słuchu czy psychologiczne nie są zakorzenione w świadomości ogółu społeczeństwa. Jednak podobnie jak zaburzenia ruchowe, zaburzenia wzroku są naturalnym etapem procesu starzenia się. Brak dostosowania przestrzeni i obiektów użyteczności publicznej dla osób niewidzących lub słabowidzących stanowi więc często barierę dla osób z wadami wzroku oraz osób starszych. W artykule przedstawiono sposoby mające na celu udogodnienie osobom niepełnosprawnym korzystania z obiektów i przestrzeni publicznych. Artykuł podzielony został na dwie części. Pierwsza obejmuje działania architektoniczno-budowlane – wskazując podstawowe zasady w kształtowaniu architektury oraz wskazując na niektóre błędy pojawiające się w obiektach budowlanych, które mogą zagrażać życiu, bezpieczeństwu lub komfortowi psychicznemu osób z dysfunkcjami wzroku. Rozwiązania architektoniczne mogą stanowić ułatwienie orientacji w przestrzeni czy odbioru bodźców środowiska architektonicznego, ale nie zawsze system informacji szczegółowej. Druga część artykułu poświęcona jest technikom tyflograficznym mogącym znaleźć zastosowanie w przestrzeniach publicznych jako formy małej architektury lub detalu – uzupełnienia architektury. Rozwiązania te wskazują na dokładniejsze informacje, takie jak system komunikacji w obiekcie, czy informacji użytkowych. Obie części artykułu wskazują na rozwiązania architektoniczne oraz ogólnie rozumianego designu mające na celu umożliwienie sprawnego i bezpiecznego funkcjonowania w obiekcie. Wskazują również na fakt, że projektowanie z uwzględnieniem osób z dysfunkcjami wzroku powinno zaczynać się już na etapie koncepcji funkcjonalno-przestrzennej, a obejmować także detal oraz rozwiązania w fazie wykonawczej oraz fazę życia obiektu przez właściwe zarządzenie przestrzenią.
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Abstract

Z powodu dynamicznego wzrostu ludności miasta niezbędne okazało się wybudowanie nowych osiedli mieszkaniowych i towarzyszących im obiektów użyteczności publicznej. Do XX wieku na terenie Opola znajdowało się jedynie pięć świątyń katolickich, które nie były w stanie pomieścić powiększającej się ilości wiernych. W związku z tym w okresie dwudziestolecia międzywojennego na terenie Opola wybudowano cztery kościoły. W poniższym artykule przedstawiono rozwiązania przestrzenne kościołów pw. św. Piotra i Pawła, pw. Najświętszego Serca Pana Jezusa, św. Józefa oraz św. Michała Archanioła.
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Abstract

Reliable monitoring for detection of damage in epicyclic gearboxes is a serious concern for all industries in which these gearboxes operate in a harsh environment and in variable operational conditions. In this paper, autonomous multidimensional novelty detection algorithms are used to estimate the gearbox’ health state based on vectors of features calculated from the vibration signal. The authors examine various feature vectors, various sources of data and many different damage scenarios in order to compare novel detection algorithms based on three different principles of operation: a distance in the feature space, a probability distribution, and an ANN (artificial neural network)-based model reconstruction approach. In order to compensate for non-deterministic results of training of neural networks, which may lead to different network performance, the ensemble technique is used to combine responses from several networks. The methods are tested in a series of practical experiments involving implanting a damage in industrial epicyclic gearboxes, and acquisition of data at variable speed conditions.
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Abstract

Videoplethysmography is currently recognized as a promising noninvasive heart rate measurement method advantageous for ubiquitous monitoring of humans in natural living conditions. Although the method is considered for application in several areas including telemedicine, sports and assisted living, its dependence on lighting conditions and camera performance is still not investigated enough. In this paper we report on research of various image acquisition aspects including the lighting spectrum, frame rate and compression. In the experimental part, we recorded five video sequences in various lighting conditions (fluorescent artificial light, dim daylight, infrared light, incandescent light bulb) using a programmable frame rate camera and a pulse oximeter as the reference. For a video sequence-based heart rate measurement we implemented a pulse detection algorithm based on the power spectral density, estimated using Welch’s technique. The results showed that lighting conditions and selected video camera settings including compression and the sampling frequency influence the heart rate detection accuracy. The average heart rate error also varies from 0.35 beats per minute (bpm) for fluorescent light to 6.6 bpm for dim daylight.
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Abstract

Noise propagation within ducts is of practical concern in many areas of industrial processes where a fluid has to be transported in piping systems. The paper presents experimental data and visualization of flow in the vicinity of an abrupt change in cross-section of a circular duct and on obstacles inside where the acoustic wave generates nonlinear separated flow and vortex fields. For noise produced by flow wave of low Mach number, laminar and turbulent flows are studied us- ing experimental sound intensity (SI) and laser particle image velocimetry (PIV) technique adopted to acoustics (A-PIV). The emphasis is put on the development and application of these methods for better understanding of noise generation inside the acoustic ducts with different cross-sections. The intensity distribution inside duct is produced by the action of the sum of modal pressures on the sum of modal particle velocities. However, acoustic field is extremely complicated because pressures in non-propagating (cut-off) modes cooperate with particle velocities in propagating modes, and vice versa. The discrete frequency sound is strongly influenced by the transmission of higher order modes in the duct. By under- standing the mechanism of energy in the sound channels and pipes we can find the best solution to noise abatement technology. In the paper, numerous methods of visualization illustrate the vortex flow as an acoustic velocity or sound intensity stream which can be presented graphically. Diffraction and scattering phenomena occurring inside and around the open-end of the acoustic duct are shown.
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Abstract

Telemedicine is one of the most innovative and promising applications of technology in contemporary medicine. Telemedical systems, a sort of distributed measurement systems, are used for continuous or periodic monitoring of human vital signals in the environment of living. This approach has several advantages in comparison to traditional medical care: e.g. patients experience fewer hospitalizations, emergency room visits, lost time from work, the costs of treatment are reduced, and the quality of life is improved. Currently, chronic respiratory diseases comprise one of the most serious public health problems. Simultaneously patients suffering from these diseases are well suitable for home monitoring. This paper describes the design and technical realization of a telemedical system that has been developed as a platform suitable for monitoring patients with chronic pulmonary diseases and fitted to Polish conditions. The paper focuses on the system's architecture, included medical tests, adopted hardware and software, and preliminary internal evaluation. The performed tests demonstrated good overall performance of the system. At present further work goes on to put it into practice.
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Abstract

Współczesne sale koncertowe z widowniami powyżej 1800 osób, prezentują szereg innowacyjnych rozwiązań przestrzennych. Mimo niewątpliwej różnorodności rzutów, większość z nich bazuje na planie Filharmonii w Berlinie, którą otwarto w 1963 r. W związku z zaobserwowanymi podobieństwami i różnicami w omawianych wnętrzach, powstających na przestrzeni lat 70. XX w., po początek lat 2000, w niniejszym opracowaniu zaprezentowano autorską typologię sal koncertowych o tzw. układzie centralnym z tarasami.
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