9762 papers found
The paper presents several problems of compression and interpolation associated with measurements in mapping ECG. There are presented two alternate methods of compression and interpolation and their implementation in processing environments. A comparative study between the results yielded applying the two methods will be done.
The molecular complementarity of the two strands of the DNA double helix makes it possible to model changes in DNA sequences manifesting by related changes in their melting temperature, thermodynamic data and optical properties. The subject of the paper is focused on metrological problems connected with modeling of a virtual integrated oligonucleotide library, basing on the analysis of fluorescence signals to be obtained as a result of hybridization.
A new velocimeter for measurements in microscopic regions is presented. A common charge coupled device (CCD) has been used as spatial filter for one-component velocity measurements. The characteristics of this sensor are investigated and first application results presented.
The principle of pulse oximetry is based on the different absorption of haemoglobin at various wavelengths in the visible and IR-region, utilizing Lambert- Beers law. With conventional oximeters a part of the human body is penetrated by radiation at two wavelengths and the oxygen saturation is calculated from the detected signals. Intention of the optical set-up presented here is the improvement of the signal-to-noise-ratio of the detected signals by a modified signal generation. Radiation of three different sources penetrates the human skin in a time-multiplex sequence, which is designated...
The determination of systolic and diastolic arterial blood pressures is very important for the diagnosis of cardiovascular diseases. Common principles for noninvasive measurements are the Riva-Rocci/Korotkow- and the oscillometric methods with inflatable cuffs around an arm, wrist or finger. In our approach we use the dependency between pulse wave velocity and arterial blood pressure to calculate systolic and diastolic pressures on a beat to beat basis. The advantage is a continuous blood pressure monitoring and the reduced stress for the patient due to the reduction of cuff inflations....
Respiration monitoring is an important part of polysomnography. Measurements are based on different principles like impedance pneumography, inductive plethysmography or the thermistor technique. Sensors disturb the patient and influence on the quality of measurement results. In this paper a real time method for computation of the respiration from the photopletysmographic signal is discussed for which only a sensor at one of human's peripheries is needed.
The structure and mechanical properties of cast alloys are closely related to the metallurgical and technological parameters of the production process. Mathematical models enabling the prediction of the structure and mechanical properties of cast alloys employ computer-aided analysis of the cooling curves scanned. The paper summarizes the results of research work aimed at obtaining data files recording the temperature waveform during the solidification of the specimens cast. The temperatures were recorded by means of type K thermocouples, and a DaqBook 100 analog to digital converter with...
This paper describes a new type temperature sensor using a modulated thermo-couple. The very low drift amplifier and the standard temperature cell used in the conventional thermo-couple sensor are not needed for the proposed sensor driven by modulating ac current. By the modulating current, both the Seebeck effect and the Pertier effect are occurred simultaneously. Therefore the output voltage by the Seebeck effect on the junction is proportional to an absolute temperature of the sensor. Especially, the method of the construction and the behaviors of the muitijunction of the sensor at low...
Abstract : Cutting temperature plays a very important role in metal cutting. The extent of the tool wear, degree of plastic deformation of the cutting edge and composition changes in the work piece material are influenced by cutting temperature. Of the several methods available for measuring cutting temperature, the tool-work thermocouple technique is the most widely used. Apart from the problem of a reliable calibration, frequent short-circuiting by the chip complicates measurement of thermo e.m.f in this method. This problem becomes more acute when multi-coated inserts with sculptured rake...
Variable temperature blackbodies are used mostly in Turkish glass and steel industries in order to calibrate their pyrometers which are used to monitor the production process. To meet the ISO-9000 requirements, these process devices have to be calibrated periodically and this requires a variable temperature blackbody, which is traceable to the National Institute. This paper describes a radiometric calibration/characterization of a variable temperature black body used in Turkish industry by using a simple portable system.