Signal-To-Noise-Ratio of Signal Acquisition In Global Navigation Satellite System Receiver

This paper presents a measurement of signal-to noise ratio (SNR) for some global navigation systems, and making a comparison between such ratios. This ratio is an important measure to the quality of the signal as SNR increases the quality increases and vice versa. A new ratio is developed here, that is (noise to signal ration)NSR, it is found that as the value of NSR increases the quality decreases. The effects of both bit time and bit error rate on both SNR and NSR  is studied.  Both bit time and bit error rate effects on SNR, as such quantities increases SNR decreases. Keywords: signal-to-noise ratio, global navigation system, signal acquisition

Performance of Retrieval Information System For Medical Images

Problem statement : In this article the principles of building knowledge and retrieval information system will be applied to medical images in some studied hospital. Since there is a huge number of medical images this system will organizes and manages the operation of retrieving and displaying such images to the persons who need such images in short time and in high quality services. Approach : From relevance assessments we can compute measures of retrieval performance such as: Recall (R), discrimination DC, and Precision. Results: both recall and precision of the system are linearly depend on relevant items correctly retrieved. Conclusion : Number of retrieved images from huge total number of medical images in some hospital determine the systems' recall, discrimination, and precision of the retrieval information system

Distribution Systems Efficiency

This paper constructing a measurement system for determining the efficiency of the distributed system. This efficiency depends on many parameters like number of terminals, number of customers and kind of information, number of nodes, and number of messages. It is found that the efficiency depends strongly on number of messages sent or received inside the distributed system, as the number of messages increased the efficiency decreased. Keywords: distributed system, terminals, efficiency