Presently, wireless sensor networks (WSNs) have created a growing attention from researchers and other stakeholders both in the industries and governments sectors. Generally, WSN could be defined as a small system of nodes which accommodatingly sense, monitor, capture, process and control situations such as data/signals around an application, supporting dealings between peoples/computer systems and the immediate surrounding . Hence, these nodes are resource-deprived and simultaneously very dependent on battery control, storing capacities, multiplication, size of data/signals and available bandwidth . Ordinarily, these nodes are static in a specific way and are left as a sole node in an isolated and human-remote point to implement tracing and recording of data.
The term wireless has turned into a generic and extensively comprehensive term employed to describe communications in which electromagnetic waves (EMWs) are employed in sending signal to several or the entire path of the communication .
According to Tiwari et al. wireless networks (WNs) are any category of computer system that applies wireless statistics networks to plug system nodes. They are computer systems which are usually not connected by cables irrespective of the category. The application of a wireless system aids enterprises to avoid the expensive means of making use of cables for buildings or connecting different equipment settings. The basis of any wireless systems is the radio waves/microwaves, and their application that ensues at the physical advanced level of network construction both for radio waves/microwaves, radio communications systems (RCSs) and other relevant EMWs. These radio waves/microwaves, RCSs and other relevant EMWs as well as mereological variables are useful in the propagation of the refractivity indices in the atmosphere.
Even if WSNs have been reported to have all it takes to allow innovative applications and by so doing contribute greatly to the innovative potential markets, there is also some possibility that the design of some WSNs is affected by several limitations which call for innovative models. According to Verdone , the action of detecting, processing and communication under restricted quantity of energy, explodes a cross-layer design method that characteristically necessitate the combined contemplation of circulated data/signal processing, intermediate access control and communication procedures.
Wireless machineries vary in several dimensions, most remarkably in what extent is the bandwidth they offer and the extent of the distance between the communicating nodes. Other vital differences which are included are possibly the electromagnetic fields (EMFs) they indicate and precisely the extent of the power them consume; this is greatly significant to mobile nodes . As reported by Tiwari et al. the four prominent wireless technologies are; "third-generation or 3G cellular wireless, Bluetooth (802.15.1), WiMAX (802.16) and Wi-Fi (more formally and generally known as 802.11)."
Presently, one of the utmost conventionally employed WSNs links is typically asymmetric; implying that both endpoints are typically categories of nodes . Occasionally, one endpoint is called the base-station (BS), usually without mobility, but with a wired (or at top high bandwidth) connected to other networks such as internet. The node at the reverse end from the connection since a “client node” could habitually be transportable and employs its link to the BS for its communication with other nodes.
WSNs have grown substantially over the years and have a momentous potential in diverse applications in areas of environmental science, medical sciences, telecommunications, education services, agriculture, surveillance, military services, etc. It has been reported that notwithstanding the influential capabilities of WSNs, their effective development is still somehow stimulating and challenging . Presently, in deploying WSNs, some programming procedures have been anticipated, which emphasis mostly on issues of low-level-based (LLB) systems. However, for the simplification of the design of WSNs and abstract from technological LLB specifics, high-level-based (HLB) methods have been developed and some advantageous resolutions have been anticipated.
Hence, in this chapter an attempt will be make at presenting an overview of WSNs machineries, some of the primary applications and values, structures in WSNs project, developments and challenges drawn from some evidence and meta-data-based survey and assessments, which is anticipated to serve as an introduction on the applications and challenges of WSNs for persons interested in WSNs.
Applications of wireless sensor networks (WSNs)
According to Buratti et al. the various conceivable applications of WSNs to every sectors globally is essentially boundless, from environmental monitoring and management, medical and health care services , as well as other aspects such as positioning and tracking ,localization, logistic. Strappingly, it is imperative to emphasize that the benefits and applications affects the choice of the wireless machinery to be employed.
As soon as the requirements of the application are set, the network designers need to select and choose the machinery which allows the gratification of these requirements. Hence, the knowledge of the structures, benefits and difficulties of the various machineries is fundamental. As a result of the significance of the relationship between the requirements for application and the machineries, this section will attempt to briefly give an outline of the some of the utmost applications of WSNs.
As stated earlier, WSNs have gained substantial admiration as a result of their flexibility in resolving issues in different application fields and have all it takes to change our world in several diverse ways. Reportedly, WSNs have been efficaciously employed in several application domains such as:
- Military Applications:
Possibly, WSNs is an essential fragment of military intelligence, facility, control, communications, computing, frontline surveillance, investigation and targeting systems.Figure 2: Wireless sensor application
- Applications in Area Monitoring:
In the aspect, the sensor nodes are positioned over an area where some display is to be observed. When the sensors notice the occurrence being observed (such as temperature, pressure etc), the occurrence is conveyed to one of the base stations (BSs), which then takes action appropriately.
- Transportation Applications:
Instantaneous traffic statistics is being composed by WSNs to later forage transportation models and keep the drivers on alert of possible congestion and traffic difficulties.
- Medical/Health Applications:
Some of the medical/health benefits of WSNs are in the areas of diagnostics, investigative, and drug administration as well as management, supporting interfaces for the incapacitated, integrated patient monitoring and management, tele-monitoring of human physiological information, and tracking and monitoring medical practitioners or patients inside the medical facility. According to Nwankwo et al. Nano informatics and nanomedicine are now beginning to advance in clinical applications via the use of biosensors.Figure 3: Medical environment
- Environmental Applications:
The term “Environmental Sensor Networks (ESNs)” has developed to cover several benefits of WSNs to environmental and earth science study. This comprises of sensing oceans, seas, glaciers, atmosphere, volcanoes, forest, etc. However, there are presently some biosensors that have been developed for use in agricultural and environmental sustainability. Some other key aspects are; air contamination monitoring and management, forest fires discovery/detection, greenhouse (GH) monitoring and management, and Landslide discovery/detection.
- Structural Applications:
WSNs can be employed for monitoring the movement of diverse structural projects such as buildings and other infrastructural projects like flyovers, bridges, roads, embankments, tunnels etc., allowing manufacturing/engineering practices to monitor possessions remotely without necessarily visiting the sites, and this would reduce expenses that would have been incurred from physical site visitations.
- Industrial Applications:
WSNs have been advanced for “Technological Condition-based Maintenance (TCBM)” since they could offer momentous cost reductions/investments and allow innovative functionalities. In wired classifications, the installation of adequate sensors is habitually limited by the amount involve in wiring.
- Agricultural Applications:
The employment of WSNs has been reported assist farmers in various aspects such as the maintenance of wiring in a problematic environment, irrigation mechanization which aids more resourceful water use and reduction of wastes.Figure 4: Agriculatural field with deployment
This chapter discusses some of the utmost issues of WSNs, ranging from applications to challenges on the technological points of view. Essentially, in designing a WSN it is required to describe the utmost appropriate technology to be employed and the communication procedures (such as signal processing, topology, approaches, etc). These selections are subject to various factors, and most significantly, the application necessities.
The first section of the chapter was keen in discussing the description of some of the limitations that should be fulfilled by the WSN and the various aspects that should be considered for designing a WSN. The proceeding section, was connected to the possibly authentic selections that could be completed, in terms of machineries. The purpose is to assist designer of WSNs in selecting or choosing of the utmost appropriate technology. The consideration was primarily focused on standard of the IEEE 802.15.4, for which also several possible performance levels are make available. Conclusively, it is suggested that a vision on imminent trends of research and prospects such as MDE techniques on WSNs should be put in place.
- Aaron Tuor, Samuel Kaplan, Brian Hutchinson, Nicole Nichols, Sean Robinson, “Deep Learning for Unsupervised Insider Threat Detection in Structured Cybersecurity Data Streams”, Proceedings of AI for Cyber Security Workshop at AAAI 2017.
- Sapna Singh, Daya Shankar Singh, and Shobhit Kumar, “Modified Mean Square Algorithm with reduced cost of training and Simulation time for Character Recognition in Backpropagation Neural Network”, Advances in Intelligent Systems and Computing, Springer International Publishing, 2014.
- Barakkath Nisha U , Uma Maheswari N , Venkatesh R and Yasir Abdullah R, “Improving Data Accuracy Using Proactive Correlated Fuzzy System in Wireless Sensor Networks”, KSII TRANSACTIONS ON INTERNET AND INFORMATION SYSTEMS VOL. 9, NO. 9, ISSN : 1976-7277, Sep. 2015
- Deqing Wang, Ru Xu, Xiaoyi Hu & Wei Su, “Energy-Efficient Distributed Compressed Sensing Data Aggregation for Cluster-Based Underwater Acoustic Sensor Networks”, International Journal of Distributed Sensor Networks, vol. 2016, pp. 1-14, 2016.