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Internet of Things (IoT) interrelates computing devices, and digital devices with animals or people and they have ability to transfer amounts of data over a network needless of any human to computer interaction. IoT is composed of sensor nodes or motes, servers, and the internet allowing these devices to collect and exchange information. Lossy networks, stressed out connections and high power consumption are the major concerns in IoT. Protocols are used for messages management and among computing nodes and they act as controls for telecommunication medium using radio frequencies. This paper, evaluates the IoT protocols’ stack over on dense network and sparse network topology which include application layer’s protocols such as, MQTT, CoAP and transport layer protocols’ UDP and TCP. Analysis is done on transport layer through RPL protocol and on physical layer using Z1 motes and Sky motes. We utilize Cooja simulator and Contiki operating system for simulations. The performance metrics for the evaluation of protocol stack are power intake, radio responsibility cycle, and average inter-packet arrival time.

Controlled-source electromagnetics is a strongly efficient technique to explore deep-water marine hydrocarbon reservoirs. However, the shallow-water unsolved limitations of electromagnetic shooting methods still exist. In this regard, this work aims to alter the existing conventional electromagnetic source such that it can converge the down-going electromagnetic wave while simultaneously dispersing the up-going electromagnetic energy to minimise the airwave in shallow water. This work presents computed electric current distribution inside a modified transmitter, using a method of moments. Simulation and an experiment-based methodology are applied to this work. Finite element simulation of the response of the modified transmitter displayed the capability of the new transmitter in dispersing the airwave, by 15%. The experimental setup confirmed a better performance of the new transmitter, showing hydrocarbon delineation of up to 48%, compared to the existing conventional transmitter, with 25% oil delineation at the same depths in the same environment. Modification of the electromagnetic source to unbalance the up-down signals may have the potential to enhance the delineation magnitude of the target signal and, as a result, significantly improve oil detection capability.

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