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EN
Precise measurements of rapid eye movements (saccades) are becoming more widespread. Because is important to answer the question whether how is a measurement error. This paper presents the measurement of about 3000 saccades in one person. It was performed in 14 times the same set of tests. For each of the 14 studies calculated mean and standard deviations of each parameter of the dynamics of eyeball movement, i.e. duration, peak velocity, average velocity, slope, sharpness, Q, and amplitude. These parameters were calculated depending on the amplitude, the type of the task and direction of eyeballs movement (left or right). The results show that the saccadic parameters are a good indicator to assess psychophysical functions.
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EN
The increased movement of eyes and eyelids is characteristic of the rapid eye movement (REM) sleep stage, making it an important indicator in sleep monitoring. A device was designed to detect this activity in a non-invasive way by means of measuring infrared light intensity reflected off the eyelid. The system converts the light intensity into current through a photodetector, performs analog signal processing and analog to digital conversion (ADC). The data is transmitted wirelessly to a computer, where the results can be displayed, stored and analyzed with a dedicated software, which also provides control over the device. The hardware is embedded in a mask, which is put over the patient's eyes. User safety in terms of mechanical, electrical and optical dangers has been ensured. The device was tested on a napping subject.
4
Content available Quality parameter assessment on iris images
88%
EN
Iris biometric for personal identification is based on capturing an eye image and obtaining features that will help in identifying a human being. However, captured images may not be of good quality due to variety of reasons e.g. occlusion, blurred images etc. Thus, it is important to assess image quality before applying feature extraction algorithm in order to avoid insufficient results. Poor quality images may affect the recognition as they have few sufficient feature information. Moreover, existing quality measures focuses on parameters or factors than feature information. In this paper, iris quality assessment research is extended by analysing the effect of entropy, contrast, area ratio, occlusion, blur, dilation and sharpness of an iris image which determines the iris size, amount of information and clearness of the features. A weighting method based on principal component analysis (PCA) is proposed to determine the influence each parameter has on the quality score. To test the proposed technique; Chinese Academy of Science Institute of Automation (CASIA), Internal Collection (IC) and University of Beira Interior (UBIRIS) databases are used. A conclusion is drawn that the combination of blur, dilation and sharpness parameters have the most influence in the quality of the image as they weighed more than other parameters
PL
Celem oświetlenia jest stworzenie takich warunków, aby znajdujący się w nich człowiek mógł wykonywać pracę wzrokową w sposób efektywny i sprawny przy jednoczesnym komforcie widzenia. Stąd konieczna jest znajomość fizycznych, fizjologicznych i psychologicznych czynników wpływających na zachowanie człowieka w określonym środowisku świetlnym oraz wpływu oświetlenia na każdy z tych czynników. W artykule przedstawiono budowę układu wzrokowego człowieka oraz procesy umożliwiające przystosowywanie wzroku ludzkiego do różnych warunków oświetleniowych. Omówiono niekorzystne, również z punktu widzenia wygody pracy wzrokowej, zjawisko olśnienia (przeszkadzającego i przykrego) oraz opisujące je zależności matematyczne. Przedstawiono zalecenia dotyczące ograniczania olśnienia przykrego we wnętrzach.
EN
In the article the structure of the human vision system and the processes enabling its adaptation in various lighting conditions are discussed. Disability and discomfort glare and the recommendation mentioning their limitation in interior lighting are also described.
EN
In the course of myopia many anatomical changes in the structure of the eyeball take place. These changes surface during early childhood. It is unclear if these changes form during the stage of foetal life. The aim of the paper was to examine whether changes which predestine to the formation of myopia occur during the prenatal period. 26 eyeballs of humans aged between 4 and 8 months of foetal life, fixed in a 10% solution of formalin were examined. The axial, equatorial and corneal dimensions were measured with Vernier calipers. The data were elaborated statistically by the Student t test, the significance level being p < 0.05. It was observed that in the course of maturation the axial length, equatorial and corneal diameter of the foetal eye increase. It was also observed that the dimensions of the eyeball expand symmetrically in all directions. This indicates that there is no predisposition to the development of myopia in the period of prenatal life.
12
Content available The influence of heavy metals on cataracts
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EN
Currently, much attention is paid to the search for the etiology of many eye diseases. It has been shown that environmental pollution with heavy metals (cadmium, lead, mercury) is of significant importance. One of these diseases is cataract, i.e. clouding of the lens of the eye. It turns out that heavy metals are deposited in the tissues of the eyes, damaging them and accelerating the disease. This work is aimed at presenting the problem of the influence of heavy metals on cataracts. The study compares the concentration of heavy metals between the control group (81 healthy volunteers) and the group of cataract patients (72 sick). Plasma was used in the research and the ICP-MS method was used.
13
Content available remote Kinetics of increased generation of ·NO in endotoxaemic rats as measured by EPR.
75%
EN
Ferrous-diethyldithiocarbamate (Fe(DETC)2) chelate is a lipophilic spin trap developed for g·NO detection by electron paramagnetic resonance (EPR) spectroscopy. Using this spin trap we investigated the kinetics of ·NO production in endotoxaemia in rats induced by lipopolysaccharide (Escherichia coli, 10 mg/kg). The NO-Fe(DETC)2 complex was found to give a characteristic EPR signal, and the amplitude of the 3rd (high-field) component of its hyperfine splitting was used to monitor the level of ·NO. We found that in blood, kindey, liver, heart and lung ·NO production starts to increase as early as 2 h after LPS injection, reaches the maximum 6 h after LPS injection and then returns to basal level within further 12-18 h. Interestingly, in the eye bulb the maximum of ·NO production was detected 12 h after LPS, and the signal was still pronounced 24 h after LPS. In brief, the highly lipophilic exogenous spin trap, Fe(DETC)2 is well suited for assessment of ·NO production in endotoxaemia. We demonstrated that the kinetics of increased production of ·NO in endotoxaemic organs, with the notable exception of the eye, do not follow the known pattern of NOS-2 induction under those conditions. Accordingly, only in early endotoxaemia a high level of ·NO is detected, while in late endotoxaemia ·NO detectability is diminished most probably due to concomitant oxidant stress.
PL
Bezpieczeństwo na drodze wymaga sprawnego funkcjonowania narządu wzroku u kierowcy. O ile w badaniach medycznych, psychologicznych bierze się pod uwagę głównie ostrość widzenia, widzenie stereoskopowe, widzenie zmierzchowe, wrażliwość na olśnienie, o tyle pomija się często badanie wrażliwości na kontrast, czyli zdolność układu wzrokowego do odróżniania przedmiotu od jego tła, mającego duże znaczenie z punktu widzenia profilaktyki bezpieczeństwa ruchu drogowego. Artykuł przedstawia wyniki badań prowadzonych w Instytucie Transportu Samochodowego na temat wpływu widzenia kontrastu na bezpieczeństwo ruchu drogowego.
EN
Safety on the road is requires an efficient performance of driver’s ocular. Unfortunately, both medical and psychological research take into the consideration factors such as visual acuity, stereoscopic vision, twilight vision, dazzle sensitivity while frequently passing over the examination on sensitivity to contrast or ability to differ an object from its background. As it turns out, the overlooked factors have a significant importance regarding the prevention in road traffic safety. The article presents the results of the research conducted in Motor Transport Institute regarding the level of contrast perception on road traffic safety.
PL
Kontrola dostępu jest dziedziną przeżywającą dynamiczny rozwój. Do niedawna wykorzystywane byty głównie zamki szyfrowe i karty z paskiem magnetycznym, ale teraz ich rolę przejęły karty zbliżeniowe. Coraz wyraźniej widać rozwój technologii umożliwiających identyfikację osób na podstawie zachowania oraz indywidualnych cech ludzkiego ciała.
PL
Oko fascynuje artystów, pisarzy i filmowców od dawna. Najczęściej jednak i w literaturze, i w kinie pojawia się w szokującym kontekście – jest wyłupiane, oślepiane itp.  Autor zastanawia się nad tym fenomenem, ale skupia się na dwóch filmach, które nie epatują okrucieństwem: Filmie Samuela Becketta i Alana Schneidera z 1965 r. i Klatce Sidneya Petersona z 1947 r. Oba filmy trwają dwadzieścia kilka minut i są nieme, ale łączy je też to, że można je interpretować, jako opowieści o rozdwojeniu jaźni.
EN
The eye fascinates artists, writers, and filmmakers for ages. Usually it appears in the violent context, is plucked out, blinded, etc. The author is deliberating on this phenomenon, but he is focusing on two films which are not a celebration of cruelty: Film by Samuel Beckett and Alan Schneider (1965) and The Cage by Sidney Peterson (1947). Both films are of similar length – twenty-something minutes – and are mute. But they have also this in common that they can be interpreted as stories about split personalities.
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