9762 papers found
Almost all of the spirometric parameters are measured or calculated during forced expiration because it is one of the most popular and most valuable tests. The American Thoracic Society (ATS) together with The European Respiratory Society (ERS) formulated the technical requirements, which should be fulfilled in spirometry today. The author shows how these requirements can be fulfilled in modern digital spirometers.
Pressure mapping provides knowledge about interface pressure between a person and the surface person is laying or sitting on. In medical applications the surface is commonly a bed or a wheelchair. The distribution of pressure applied to the skin by a supporting surface can be measured with a pressure mapping system. Depending on the magnitude and duration of the pressure, it can cause pain and tissue injuries, such as pressure ulcers to the person. By means of pressure mapping technology, it is possible to detect the areas where the pressure is concentrated and thus prevent the development...
New 3D medical images reconstruction algorithm is presented in this paper. It concerns utilization of digital processing and analysis of Computed Tomography images in process of 3D lungs reconstruction.
The paper presents different methods of combining many neural classifiers into one ensemble system for recognition and classification of arrhythmia. Majority and weighted voting, Kullback-Leibler divergence and modified Bayes methods will be presented and compared. The numerical experiments will be performed for the problems concerning the recognition of different types of arrhythmia on the basis of ECG waveforms of MIT BIH AD.
Multichannel system for ECG measurement and body surface potential mapping is introduced and its application for noninvasive identification of ischemic heart regions with changed repolarization is presented. The system uses up to 128 active electrodes, separate common mode signal sensing and active neutralization of the patient to get optimal signal quality. Microprocessor controlled and battery powered data acquisition module is connected through an optical extension cable to the USB port of a personal computer with Windows based measuring and data analysis software. In 11 patients with...
The paper presents an imaging reflectometer designed to detect flicker-induced reflectance changes of the ocular fundus. The system is based on a modified fundus camera completely controlled by a personal computer via USB interface. The system allows in-vivo functional imaging of the ocular fundus in the near-infrared region with flicker light stimulus in the visible spectrum.
In this paper we propose a simple method aiming at improving the visibility of the loss of the gray-white matter interface in computer tomography (CT) brain images. The loss of the gray-white matter interface is one of the early signs of acute cerebral artery infarction (ACAI). The method is to employ our proposed adaptive smoothing filter (ASF) to reduce local noise with edges preserved in CT brain images. The ASF is a specially designed filter with adaptive size and shape depending on local pixel-valuerelated information surrounding the pixel of interest. In order to demonstrate the...
The authors present a model of the respiratory system in forced expiration as an answer to the unknown pressure pulse excitation. The model has the form of a voltage divider circuit, where gas flow volume velocity is the current reaction (or the volume is the voltage reaction). The analysis is presented in time domain. The model’s finding is realized in two main stages. In the first stage an RCL net is built. On the basis of this structure the exciting signal is found in the form that the answer to the model is V(t) (or Q(t)), very similar to the real object’s answer, in the minimum...
An ice point blackbody cavity has been designed and constructed at NML-SIRIM, Malaysia. It is a mean to measure the ice point reading of client’s infrared radiation thermometer that operates near 0 °C. The ice point check will predict the performance of the thermometer at other temperature range.
A mini TPW system was introduced as an excellent way to measure the errors in the calibration system of a secondary level temperature laboratory. In this paper, the structure and operation of this system is briefly introduced. Also, its performance is discussed. The mini TPW system was directly compared to a traditional TPW cell. The difference between the mini TPW system and the traditional TPW cell was found to be less than 0.3 mK using an SPRT. The expanded ( k = 2) uncertainty of the mini TPW system is better than 0.5 mK. Several thermometers with different structures were tested in the...