Chemical sensors have been attractive for scientific research and industrial applications. This paper proposes that the detection and recognition of a chemical concentrate can be achieved by means of passive and compact size fiber optic sensor based on "Fiber Bragg Gratings Technology". A mathematical model of a short period fiber Bragg gratings chemical sensor has developed.
Fiber Bragg gratings (FBGs) have been widely used in optical communication systems for wavelength tuning and dispersion compensation. FBGs are made by laterally exposing the core of a single-mode fiber to a periodic pattern of intense ultraviolet light. This proposes that, by exposing the fiber core to other temporary and alternative exposure sources in real time may create a gratings effect which is so called “real time virtual gratings”. The virtual gratings can be classified as a real time adaptive fiber Bragg gratings which may be used in dispersion compensation applications.
Time-transfer is the process of using a GPS receiver to derive accurate time relative to GPS system time. The GPS receiver clock error establishes the relationship between the receiver’s time and the GPS system time. The main problem here is to estimate the desired range equivalent of receiver clock error. Kalman filter is one of the methods used to estimate the various error components separately using observations made over time. This paper proposes the use of neural networks for the estimation of these error components based on a revised time-transfer error model.
An artificial nose has been attractive for scientific research and the food industry. This paper proposes that the detection and recognition of odours or chemicals concentrate can be achieved by means of passive and compact size fiber optic sensors (Fiber Bragg Gratings Technology) that will form an olfactory sensor array and a fuzzy logic algorithm that will form the recognition artificial intelligence. The mathematical model of the fiber Bragg gratings olfactory sensor is developed and the design model of the artificial fiber optic nose is introduced.
KEYWORDS: Data acquisition, Human-machine interfaces, Data communications, Telecommunications, Data processing, Signal processing, Heart, Medicine, Data archive systems, Computer programming
In Intensive Care Unit (ICU) patient’s physiological variables such as heart rate, blood pressure, temperature, ventilation and brain activity are constantly monitored on-line, and medicine doses are given to ensure that these variables remain within desired limits. Such data are vital not only for on-line but also for off-line analyses and for medical staff training. Furthermore, in cases of deceased patients it is very important to retrieve these data in order to investigate the causes of deaths. This paper is introducing a design of a Real-Time Data Acquisition System for monitoring patients in Intensive Care Unit (ICU). The proposed design is implemented on a standard personal computer (PC) and operating system without using any sophisticated hardware or interface devices.
In today's life, remote environmental sensing via distributed and remote telemetry stations is a vital demand for pollution control and wildlife protection. However the high cost of sensors and their environmental ruggedness, engineering and equipments' cost, and the complex signal processing are restricting the spread of such technology. This paper is introducing the design and modelling of a compact size environmental telemetry station (CETS) based on passive optical sensors and Fuzzy logic control. Here, the cost reduction and size problems are solved by using the fiber Bragg gratings sensors that are able to detect a wide variety of environmental variables such as temperature, humidity, toxic gases, odours, chemical pollution, water dissolved toxins, level, pressure and many more. Also the complex signal processing problem is solved by using an array of fiber Bragg gratings sensors that coexist on a single fiber core, where their signals are multiplexed and processed in the optical domain without the need to analogue-to-digital conversion. The control and encoding problem is solved by using a Fuzzy logic control algorithm within an imbedded system fitted with a CCD sensor spectrometer.
Although tunable fiber Bragg gratings are flexible and promising solutions for dispersion compensation, but we still have the problems of variable optical communication path characteristics, environmental fluctuations and the variety of applications, that require re-design and fabrication of fiber Bragg gratings for each case. An alternative novel technique of dispersion compensation based on adaptive fiber Bragg gratings scheme would overcome these problems. In this paper three different real time adaptive dispersion compensation schemes, are introduced; scheme based on pulse shape detection, scheme based on crosscorrelation detection and scheme based on pattern recognition.
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