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<jats:p>Steganography is a science of hiding the presence of data so that it remains safe from intruders. In modern communication scenarios, the use of steganography is very valuable. It can protect the insecurity of wireless communication channels and having enough capability to surprise intruders. In this paper, a brief introduction of steganography along with its association to cryptography is discussed and we believe that it will be very helpful in the development of security protocols for various applications.</jats:p>

<jats:p>Humans and computers are suited to different types of tasks. Like, finding the sine of any number is difficult for humans, but easy for the computers. On the other hand, looking and identifying the image of a bird is very easy for us, as compared to the machines [1]. But nowadays, Artificial neural networks or ANNs are most commonly used in image processing. In fact, the recent deep learning algorithms have surpassed the human ability of image recognition. It is proved and stated that BPNN (Backpropagation Neural Networks) have a very high accuracy. A large part of recent success of neural network is explained on the basis of very high data availability. Thus, in B-P the network is trained with a lot of training examples so that it doesn’t compromise with the efficiency of the system. By the end of this century, it is expected that computers will be training neural networks with as many neurons as the human brain has [1][2]. Although it is difficult to predict what the true abilities of artificial intelligence will be by then, our experience with computer vision should prepare us to expect something unexpected. So, with this attempt paper tries to give the idea of how image is recognized and how back propagation works.</jats:p>

<jats:p>This study presents the evaluation of signal strength and quality of a ku-band satellite downlink signals during raining season in Guinea Savanna region of Nigeria. Rain rate data and ku-band signal over Jos were retrieved from the Nigeria Meteorological Agency (NIMET). Rain rate data was measured using Davis Vantage Vue weather station while microwave signal were obtained using spectrum analyzer. The measured data were analyzed using Microsoft office excel. Rainfall is broadly classified into two types: stratiform (drizzle: ≤5mm/hr and widespread: &gt;5≤25mm/hr) and convection (shower: &gt;25≤50mm/hr and thunderstorm: &gt;50mm/hr). Results were calculated based on ITU-Recommendations P.618-12 and P.838. The results obtained revealed that the effect of rain on signal strength and quality on a ku-band link depend on the rain type and duration of rainfall. The effect of drizzle (≤5mm/hr) on the ku-band link is not significant regardless the duration of rainfall. The results also shows that severe signal losses above 60dB were obtained under shower (&gt;25≤50mm/hr) and thunderstorm (&gt;50mm/hr). Also, widespread (&gt;5≤25mm/hr) that prevailed for a longer period causes severe signal losses. This is to say that lower rain rate of about 25mm/hr that prevailed for a very long time have significant effect on Kuband link. The results of this study will serve as crucial design parameters for communication systems engineers for providing fade margins and developing accurate fade mitigation techniques (FMTs) for the Guinea Savanna region of Nigeria. It was observed from this study that the experimental studies within the Ku-band frequency are getting over exhausted. Therefore, experimental studied in the region of higher band like K and Ka are highly recommended.</jats:p>

<jats:p>In this paper we show that queueing theory can accurately model the flow of in-patient in hospital. In which arrival rate, service rate and number of parallel servers are all considered as fuzzy numbers. Further Robust Ranking technique is used to find the expected mean queue length and waiting time in queue. Further numerical illustration is also given to justify the validity of the model. In this model capacity of the system is infinite.</jats:p>