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1
PL
Artykuł podejmuje kwestię istoty kartografii analizowaną w kontekście dynamicznie rozwijającej się technologii geoprzestrzennej. Skoncentrowano się przy tym na problematyce modelowania kartograficznego, które poddano analizie pod kątem jego fundamentalnych cech. Jednocześnie wybrano wiele innych modeli rzeczywistości (niekartograficznych) i przeprowadzono ocenę występowanie w nich konkretnych cech właściwych dla modelowania kartograficznego. W ten sposób dokonano zdefiniowania unikalnego zestawu cech jakim modelowanie kartograficzne wyróżnia się od innych reprezentacji rzeczywistości, takich jak na przykład: obrazowanie przestrzeni w grze komputerowej, w systemie klimatycznym bądź w formie obrazu artystycznego. Przeprowadzone analizy i rozważania skłaniają autorów do uznania modelowania kartograficznego za unikalny proces portretowania przestrzeni geograficznej, stanowiącego jednocześnie jądro domeny kartografii.
EN
The paper raises an issue of essence of cartography studied in the context of a dynamically developing geospatial technology. It focuses on cartographic modelling issues, which were analysed in terms of its fundamental features. At the same time, a number of other reality (non-cartographic) models were selected and the assessment of their features specific to cartographic modelling was carried out. In this way, a unique set of features has been defined that distinguishes a cartographic modelling itself from other representations of reality, such as imaging of space in a computer game, modelling a climate system or in the form of an artistic image. Conducted analyses and considerations moved the authors towards recognition of cartographic modelling as a unique process of portraying the geographical space, which is also the nucleus of the cartography domain.
EN
The issue of line simplification is one of the fundamental problems of generalisation of geographical information, and the proper parameterisation of simplification algorithms is essential for the correctness and cartographic quality of the results. The authors of this study have attempted to apply computational intelligence methods in order to create a cartographic knowledge base that would allow for non-standard parameterisation of WEA (Weighted Effective Area) simplification algorithm. The aim of the conducted research was to obtain two independent methods of non-linear weighting of multi-dimensional regression function that determines the “importance” of specific points on the line and their comparison to each other. The first proposed approach consisted in the preparation of a set of cartographically correct examples constituting a basis for teaching a neural network, while the other one consisted in defining inference rules using fuzzy logic. The obtained results demonstrate that both methods have great potential, although the proposed solutions require detailed parameterisation taking into account the specificity of geometric variety of the source data.
PL
Celem artykułu jest przedstawienie wyników analizy czasowo-częstotliwościowej sygnałów fonokardiograficznych. Powodem podjęcia działań dotyczących badania tego typu sygnałów są statystyki Światowej Organizacji Zdrowia, które od lat wskazują, iż pierwszą przyczyną zgonów na świecie są choroby układu sercowo-naczyniowego [1]. Powodem dominacji tego typu schorzeń w statystykach jest rosnący stres psychospołeczny oraz malejąca aktywność fizyczna społeczeństwa. Badanie tonów serca i detekcja schorzeń w oparciu o sygnał fonokardiograficzny na wczesnym etapie badań lekarskich może skutecznie przyczynić się do zmniejszenia wysokich statystyk umieralności. W artykule przedstawiono wyniki opracowanego algorytmu, który dla 15 osobowego zbioru przypadków charakteryzuje się czułością na poziomie 100% i specyficznością równą 87,50%, co z medycznego punktu widzenia jest wynikiem satysfakcjonującym.
EN
The aim of this article is to present the results of time-frequency analysis of phonocardiographic signals. The reason for undertaking such studies is the World Health Organization (WHO) statistics, which for years have shown that cardiovascular disease is the leading cause of death in the world [1]. The reason for the dominance of this type of illness in statistics is the increasing psychosocial stress and decreasing physical activity of the population. Heart rate and disease detection based on phonocardiographic data at an early stage of medical examination can effectively contribute to the reduction of high mortality statistics. The paper presents the results of the developed algorithm, which for the 15-person case collection is characterized by a sensitivity of 100% and a specificity of 87.50%, which is a satisfactory result from the medical point of view.
PL
W artykule przedstawiono oparty na Metodzie Statystycznej Analizy Energii model izolacyjności akustycznej pojedynczych przegród jednorodnych. Porównano wyznaczone charakterystyki częstotliwościowe izolacyjności akustycznej od dźwięków powietrznych przegród modelu obliczeniowego z wynikami badań doświadczalnych. Obliczenia przy wykorzystaniu modelu Metody Statystycznej Analizy Energii oraz badań laboratoryjnych przeprowadzono dla płyt wykonanych z pleksiglasu i akrylu.
EN
The article presents the model of sound insulation of single homogeneous baffles based on the Statistical Method of Energy Analysis. The determined frequency characteristics of airborne sound insulation of the baffles obtained from the calculation model with the results of experimental tests were compared. Calculations using the Statistical Method of Energy Analysis and laboratory tests were performed for plates made of plexiglass and acrylic.
PL
W artykule opisano podstawowe metody teoretycznego wyznaczania izolacyjności akustycznej właściwej przegród jednorodnych. W pracy autorzy rozważania ograniczyli do modeli opartych na wykorzystaniu impedancji mechanicznej przegrody. Przegrodę zamodelowano jako: bryła sztywna, odkształcalna płyta cienka (opisana modelem Kirchhoffa-Love’a) i gruba (model Mindlina–Reissnera). Wartości izolacyjności akustycznej uzyskane dla tak opisanych modeli porównano dla kilku materiałów stosowanych na obudowy maszyn.
EN
In the paper basic theoretical models of transmission loss calculation are described. Here only single homogeneous isotropic panels are analysed. Three impedance values of one rigid and two flexible body models of panel are described and analysed. As flexible models the thin plate (Kirchhoff-Love plate model) i thick (Mindlin-Reissner model) are analysed.
PL
W pracy przedstawiono bezsiatkową metodę kolokacyjną Kansy i jej zastosowanie do analizy drgań własnych płyty wykonanej z dwóch materiałów. W analizie wykorzystano funkcje Wendlanda, zaś uzyskane wyniki porównano z wynikami symulacji Metodą Elementów Skończonych.
EN
This paper describes a meshless Kansa collocation method and its application to dynamic analysis of a two material plate. Wendland functions were used in analysis. All results were compared to Finite Element Method result.
7
Content available remote Wieloaspektowa analiza spektralna sygnałów fonokardiograficznych
PL
W artykule przedstawiono koncepcję analizy spektralnej sygnałów fonokardiograficznych. Zaprezentowano wyniki analizy sygnałów zawierających od kilku do kilkunastu uderzeń serca oraz sygnałów krótkich zawierających pojedyncze uderzenie serca. Przedstawiono propozycje kilkudziesięciu widmowych cech dystynktywnych oraz ocenę ich przydatności w diagnostyce schorzeń kardiologicznych.
EN
The article presents the idea of spectral analysis of phonocardiographic signals. The results of analysis of signals containing from several to over a dozen heartbeats and short signals containing only one heartbeat. Proposals dozens of spectral distinctive features and evaluate their usefulness in the diagnosis of cardiac diseases.
EN
Streaming velocity depends on intensity and absorption of ultrasound in the media. In some cases, such as ultrasound scattered on blood cells at high frequencies, or the presence of ultrasound contrast agents, scattering affects the streaming speed. The velocities of acoustic streaming in a blood-mimicking starch suspension in water and Bracco BR14 contrast agent were measured. The source of the streaming was a plane 20MHz ultrasonic transducer. Velocity was estimated from the averaged Doppler spectrum. The single particle driving force was calculated as the integral of the momentum density tensor components. For different starch concentrations, the streaming velocity increased from 8.9 to 12.5mm/s. This corresponds to a constant 14% velocity increase for a 1 g/l increase in starch concentration. For BR14, the streaming velocity remained constant at 7.2mm/s and was independent of the microbubbles concentration. The velocity was less than in reference, within 0.5mm/s measurement error. Theoretical calculations showed a 16% increase in streaming velocity for 1 g/l starch concentration rise, very similar to the experimental results. The theory has also shown the ability to reduce the streaming velocity by low-density scatterers, as was experimentally proved using the BR14 contrast agent.
PL
W artykule przedstawiono projekt systemu, przeznaczonego do zdalnego i ciągłego monitorowania zmian ciśnienia tętniczego krwi oraz wyniki badań testowych. Przedstawiony system złożony jest z osobistego urządzenia pomiarowego, punktu dostępowego do sieci Internet oraz ogólnodostępnego serwera danych. Istotnym elementem projektowanego systemu jest metoda ciągłego pomiaru zmian ciśnienia krwi, polegająca na określaniu czasu propagacji fali tętna. Czas ten wyznaczany jest pomiędzy charakterystycznym punktem sygnału elektrokardiograficznego (EKG) i sygnału fotopletyzmograficznego (PPG). W artykule przedstawiono wyniki badań testowych, dotyczących wyznaczania punktów charakterystycznych sygnału EKG i PPG metodą autokorelacyjną oraz wyniki pomiaru zmian czasu propagacji fali tętna.
EN
The article presents the design of the system for remote and continuous monitoring of changes in blood pressure and also results of the test. Presented system consists of a personal measuring device, the access point to the Internet and widely available data server. An important element of the designed system is a method for continuous measurement of changes in blood pressure, which based on determining the pulse wave transit time. This time is calculated between the specific point electrocardiogram (ECG) signal and the photoplethysmographic signal (PPG). The article presents the results of test on the determination of specific points of the ECG signal and the PPG based on autocorrelation method and the results of measuring changes in pulse wave transit time.
PL
W artykule opisano możliwości zastosowania Metody Funkcji Radialnych do wyznaczania akustycznych częstotliwości drgań własnych w przestrzeniach ograniczonych. Porównano metodyki popularnych narzędzi obliczeniowych takich jak Metoda Elementów Skończonych i Metoda Elementów Brzegowych wraz ze wskazaniem wad i zalet do Metody Funkcji Radialnych.
EN
In the paper the possibility of Radial Basis Function Method for the calculation of acoustic eigenvalues is described. The proposed method is compared with other numerical methods of wave acoustic. The advantages and disadvantages of Finite Element Method and Boundary Element Method are described and compared to proposed Radial Basis Function Method.
PL
W pracy przedstawiono bezsiatkową metodę kolokacyjną Kansy i jej zastosowanie do analizy drgań własnych powłoki walcowej swobodnie podpartej. W analizie wykorzystano funkcję wielokwadratową, zaś uzyskane wyniki porównano z wynikami obliczeń uzyskanymi z modelu analitycznego.
EN
This paper describes a meshless Kansa collocation method and its application to dynamic analysis of a cylindrical shell. Multiquadratic functions were used in analysis. All results were compared to analytical result.
12
Content available remote The measurement system for analyzing heart sounds with ECG reference signal
EN
This article present the problem of measurement and analysis heart sounds, and designed the measuring system for recording and analyzing heart sounds and murmurs to isolate specific factors, that allow in future to differentiate specific cases of heart disease. This text presents the issue of listening the heart beat and murmurs in the non-acoustic band in the context of physiological and pathological processes occurring in the human body, and the imperfections of human hearing.
PL
W artykule przedstawiono problematykę pomiarów i analizy dźwięków serca oraz wykonany system pomiarowy służący do rejestracji i analizy tonów i szmerów serca w celu wyodrębnienia cech dystynktywnych pozwalających w dalszej perspektywie na różnicowanie określonych przypadków chorobowych. Przedstawiono problematykę odsłuchu tonów i szmerów serca w zakresie niskich częstotliwości w kontekście procesów fizjologicznych i patologicznych zachodzących w organizmie ludzkim oraz niedoskonałości ludzkiego słuchu.
EN
The identity of cartography is determined by the manner of defining and interpreting the concept of “map”. However, the term has not been unequivocally articulated as yet. There are many different definitions of maps available in literature - from those viewing map as a scaled-down, planar, graphic representation of geographical space, to those that equate a map to a specific model that is independent of the form of its presentation. Interestingly enough, the basis of such universal treatment of the map concept can be found already in the scientific works from the 1960s. Although contemporary definitions do not limit a map to a single form of presentation, such over-simplification still persists. The issue has become very relevant given the rapidly increasing number of diverse geospatial applications designed to access spatial data and present it in diverse forms. So far, however, there are no clear rules for categorizing a given representation as cartographic or non-cartographic. And this often gives rise to various misconceptions, e.g. regarding the role and responsibilities of cartography as science and practical activity. According to the authors of the article, a map is an ordered informational structure shaped by the years of practical experience and research in the field of cartography. Map arising in the process of cartographic modelling is understood as one of many possible models of the portrayed space. The model is formed in the course of thought processes, including abstraction and generalization in particular. Creation of the model involves the use of symbolism that can be decoded by the recipient.This does not mean, however, that the process of symbolization is limited exclusively to graphical representations. Map is also a tool for presenting spatial information in a visual, digital or tactile way. Therefore, the essence of map is determined by its “model” nature rather than the format of the cartographic message. The authors have assumed that map is formed in the process of cartographic modelling and certain properties of the process can be defined, that distinguish it from other methods of spatial modelling. The properties recognized as characteristic for cartographic modelling include space portraying that enables identification of types of objects and phenomena, describing spatial relationships between objects, as well as their positioning in the applied reference system. In the authors’ opinion, properties of cartographic modelling include also the intentional application of a specific level of generalization determined by the objective of the map, aware authorship of the message, unambiguity of communication and symbolization based on knowledge. The proposed approach should facilitate the classification of different products designed to represent space.
EN
Background: There is a growing interest in the application of non-invasive clinical tools allowing one to assess the endothelial function, preceding atherosclerosis. The precision in estimating of the artery Flow Mediated Vasodilation (FMD) using standard 10-12 MHz linear array probes does not exceed 0.2 mm, far beyond that required. Methods: We have introduced a wide-band, high frequency 25-30 MHz, Golay encoded wobbling type imaging to measure dilation of the radial artery instead of the brachial one. 18 young volunteers, and 4 volunteers with cardiac events history, were examined. In the second approach 20 MHz linear scanning combined with 20 MHz pulsed Doppler attached to the linear array was used. The radial artery FMD was normalized using shear rate at the radial artery wall. Results and Conclusions: For the “healthy” group, the FMD resulting from reactive hyperemia response was over 20%; while in the “atherosclerotic” group, the FMD was at least twice as small, not exceeding 10%. The shear rate (SR) normalized FMDSR was in the range from 7.8 to 9.9 in arbitrary units, while in patients with minor cardiac history FMDSR was clearly lower, 6.8 to 7.6. The normalized FMDSR of radial artery RARR can be an alternative to the brachial FMD where the precision of measurements is lower and the diameter dilation does not exceed 7-10%.
EN
Acoustocerebrography (ACG) is a set of techniques designed to capture states of human brain tissue, and its changes. It is based on noninvasive measurements of various parameters obtained by analyzing an ultrasound pulse emitted through the human’s skull. ACG and Magnetic Resonance Imaging (MRI) results were compared in a clinical study assessment of focal white-matter-lesions (WML) in the brains of patients with asymptomatic atrial fibrillation (AAF). The clinical study included 55 patients (age 66.1 ± 6.7 years). According to MRI data, the patients were assigned into four groups depending on the number of lesions: L0 - 0 to 4 lesions, L5 - 5 to 9 lesions, L10 - 10 to 29 lesions, and L30 - 30 or more lesions. As a result, it has been concluded that the ACG method could clearly differentiate the groups L0 (with 0 ÷ 4 lesions) and L30 (with more than 30 lesions) of WML patients. Fisher’s Exact Test shows that this correlation is highly significant (p < 0.001). ACG seems to be a new, effective, method for detecting WML for patients with AAF and can become increasingly useful in both diagnosing, and in stratifying, them. This, in turn, can be helpful in individualizing their treatment, so that the risk of strokes may become essentially reduced.
EN
In this paper, we present a new brain diagnostic method based on a computer aided multispectral ultrasound diagnostics method (CAMUD). We explored the standard values of the relative time of flight (RIT), as well as the attenuation, ATN, of multispectral longitudinal ultrasound waves propagated non-invasively through the brains of a standard Caucasian volunteer population across different ages and genders. For the interpretation of the volunteers health questionnaire and ultrasound data we explored various clustering and classification algorithms, such as PCA and ANOVA. We showed that the RIT and ATN values provide very good estimators of possible physiological changes in the brain tissue and can differentiate the possible high-risk groups obtained by other groups and methods (Russo et al. [1]; Lloyd-Jones et al. [2]; Medscape [3]). Special attention should be given to the subgroup which included almost 39% of the volunteers. Respondents in this group have a significantly increased minimum ATN value (see Classification Trees). These values are strongly correlated with the identified risk of stroke factors being: age, increased alcohol consumption, cases of heart disease and stroke in the family as already shown by Rusco and as incorporated into Lloyd-Jones et al., ‘‘Heart Disease and Stroke Statistics – 2009 Update’’, by the American Heart Association (AHA) and American Stroke Association (ASA), as updated recently in the 2015 ‘‘Stroke Prevention Guidelines’’.
PL
W pracy przedstawiono bezsiatkową metodę kolokacyjną Kansy i jej zastosowanie do analizy drgań własnych płyty z otworami. W analizie wykorzystano funkcje Wendlanda, zaś uzyskane wyniki porównano z wynikami symulacji Metodą Elementów Skończonych.
EN
This paper describes a meshless Kansa collocation method and its application to dynamic analysis of a plate with holes. Wendland functions were used in analysis. All results were compared to Finite Element Method result.
PL
W ramach innowacyjnego projektu geoinformacyjnego B+R finansowanego ze środków POIG Wydział Geodezji i Kartografii Politechniki Warszawskiej wraz firmą Intergraph oraz z Wrocławskim Instytutem Zastosowań Informacji Przestrzennej i Sztucznej Inteligencji realizuje temat „Opracowanie i wdrożenie innowacyjnej technologii GeoMedia Enterprise Intelligence realizującej wielokryterialną analizę danych przestrzennych w środowisku narzędziowym desktop oraz Web”. W ramach nawiązanej współpracy możliwe stało się wdrożenie opracowywanych od lat przez Zakład Kartografii PW algorytmów typu spatial data mining, umożliwiających uwzględnienie aspektu przestrzennego w analizach statystycznych. Autorzy pragną uzyskać wartość dodaną poprzez połączenie w celowy ciąg technologiczny szeregu analiz geostatystycznych, wzbogaconych o zaawansowane wizualizacje kartograficzne. W ciągu tym zaproponowano algorytmy mające służyć wstępnemu przetworzeniu danych, w tym metodę agregacji i metodę reduktów, oraz szereg klasycznych metod statystycznych wzbogaconych o ujęcie lokalne i powiązania przestrzenne.
EN
The Cartography Department of Geodesy and Cartography Faculty of Warsaw University of Technology, in collaboration with Intergraph Poland Sp. z o. o. and Wroclaw Institute of Spatial Information and Artificial Intelligence works on the subject of "Development and implementation of innovative technology GeoMedia Enterprise Intelligence in multicriteria spatial data analysis in both desktop and Web environment" This R&D project is funded by the Innovative Economy Operational Programme EU in Poland. Within the framework of this cooperation it became possible to implement new algorithms as well as to extend the existing ones (touching most of the spatial aspects to be included in the analysis) which were developed in the Cartography Department. The authors intend to obtain added value by combining a number of spatial statistics analyses, enriched by cartographic visualizations, into a purposeful workflow. The algorithms included in the workflow cover among others methods of data preprocessing, including data reduction (aggregation and reducts) as well as number of classical statistical methods enriched by the local approach and spatial neighborhood.
EN
The main aim of this study was to verify the suitability of the hydrogel sonographic model of the left ventricle (LV) in the computed tomography (CT) environment and echocardiography and compare the radial strain calculations obtained by two different techniques: the speckle tracking ultrasonography and the multislices computed tomography (MSCT). The measurement setup consists of the LV model immersed in a cylindrical tank filled with water, hydraulic pump, the ultrasound scanner, hydraulic pump controller, pressure measurement system of water inside the LV model, and iMac workstation. The phantom was scanned using a 3.5 MHz Artida Toshiba ultrasound scanner unit at two angle positions: 0° and 25°. In this work a new method of assessment of RF speckles' tracking. LV phantom was also examined using the CT 750 HD 64-slice MSCT machine (GE Healthcare). The results showed that the radial strain (RS) was independent on the insonifying angle or the pump rate. The results showed a very good agreement, at the level of 0.9%, in the radial strain assessment between the ultrasound M-mode technique and multislice CT examination. The study indicates the usefulness of the ultrasonographic LV model in the CT technique. The presented ultrasonographic LV phantom may be used to analyze left ventricle wall strains in physiological as well as pathological conditions. CT, ultrasound M-mode techniques, and author's speckle tracking algorithm, can be used as reference methods in conducting comparative studies using ultrasound scanners of various manufacturers.
PL
W artykule przedstawiono wyniki badań obejmujących wizualizację danych topograficznych BDOTIOk i ich publikację w dedykowanym serwisie internetowym. Jednym z celów projektu było określenie zbioru zasad optymalizacji wizualizacji kartograficznej i opracowanie efektywnych sposobów ich publikacji. Wykazano, iż o efektywności lub szerzej - użyteczności mapy jako środka przekazu informacji, oprócz odpowiedniego doboru danych źródłowych, decyduje również czytelność obrazu, logika systemu znaków umownych, estetyka kompozycji oraz funkcjonalność aplikacji internetowej - w przypadku tego środka dystrybucji map.
EN
One of the key challenges in the process of development of IIP (Infrastructure for Spatial Information) in Poland is the construction of a complex model of a multi-resolution database of topographic objects. Effective implementation of an MRDB-type database requires development of geographic information generalization procedures, as well as a method of visualization of spatial data compliant with classical cartographic methodology. The main assumption of contemporary approach to the edition of Polish topographic maps is a significant extension of a semi-automatic stage of generation of cartographic image from BDOTIOk (database of topographic objects) and BDOO (database of geographic objects), with graphic coherence all through the scale series. Altitude presented through contour lines and shading should also be an important element of topographic maps. To facilitate the evaluation of the process of map edition and effectiveness of the resulting cartographic presentation, three levels of visualization of spatial data have been determined. They are conditioned by the applied GIS technology and are linked to the extent of application of cartographic methodology. The first level is raw visualization, the second - auto¬matic cartographic visualization, and the third - cartographic presentation. The results of the so-defined editorial process basing on BDOT referential data are presented in the form of topographic maps of new generation and in a geo-information on-line service. An experimental geo-information service has been designed and launched; it complies with the basics of cartographic methodology and the rules of optimization of cartographic visualization, which is the basic element guaranteeing usefulness of the geo-service, such as: widespread accessibility, quality of information, graphic and cartographic quality (projection, symbolization, generalization) and ergonomics. Functionalities of the prototype of such a service are described: parallel display of topographic maps in various scales, with an option of synchronization of images and scales. The realized projects provided a wider context for the issue of effectiveness, and primarily for the selection of methods and means of cartographic presentation which would guarantee effective communication in the sense of conveying the contents, efficiency, ease of use, information reliability and general usability for the reader.
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