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This work proposes the design and operation methodologies of a wireless sensor network (WSN) in the greenhouse environment that can lead to the development of an advanced, distributed monitoring and control system. The combined use of conventional sensors with remote sensing technology embedded in a WSN, together with processing algorithms that provide the synthesized information (e.g. performance indicators) required for optimal greenhouse control and decision making, lead to the development of an integrated climate monitoring and control system, towards the realization of precision greenhouse horticulture. Several specific problems related to greenhouse environments are addressed in this work, towards the feasibility of WSNs usage inside the greenhouse, like wireless nodes packaging, standardization of WSN components, electromagnetic fields interference, effects of greenhouse cover materials, etc. The performance of the fine-tuned WSN is evaluated, based on real-time measurements and communication and energy consumption metrics.

In modern greenhouses, several measurement points at plant level are required to create an objective and detailed view of the climate at various regions around the covered space. Specific climatic gradients can cause significant differences in terms of yield, productivity, quantitative and qualitative characteristics of the plants, as well as the development of various diseases. This work presents the development of a distributed monitoring system using a wireless sensor network (WSN) in a commercial greenhouse, towards the realization of a spatially distributed control methodology, based on specific spatial variations of the measured environmental variables. The distributed measurements acquired by the wireless nodes are analysed to represent the spatial variation of the environmental conditions inside the greenhouse, which can subsequently be used to develop precise control strategies that could lead to more uniform conditions throughout the entire cultivation area and better control of crop needs. In this way, uniform quantity and quality of produce can be achieved, while the risk of diseases at specific problematic regions of the greenhouse could be minimized. Analysis based on WSN measurements during summer and winter periods showed significant spatial variability in temperature and humidity, but also in transpiration and conditions that favour condensation on leaves surface.

Precision greenhouse agriculture requires several measuring points in order to have a better overview of the whole cultivation area. Climate variability within the covered area of a greenhouse can result in a non-uniform plant development and reduced productivity. Therefore, a distributed system, capable of taking multi-point measurements would be able to catch the climatic gradients in order to provide growers with a more detailed depiction of the climate at any time and early warnings of potential threats. Furthermore, the distributed monitoring can offer the appropriate inputs to more sophisticated distributed or plant-based climate control algorithms. The significant price drop in embedded computer and wireless communication chips, as well as the overall maturity of the available, low-power platforms have made the deployment of Wireless Sensor Networks increasingly attractive in modern agricultural facilities. This paper presents a Wireless Sensor Network (WSN) deployed for long periods in commercial facilities, equipped with shading screens and cooling pads placed in different directions, namely vertically to the plantation and parallel to it. The evolution of the various climate parameters in both greenhouses and the effect of the climate on the plants and the wireless communications are analyzed and presented.

Government. One of the major issues is that we develop in Agile but the accreditation process is conducted using Waterfall resulting in delays to go live dates. Taking a brief look into the accreditation process that is used within Government for I.T. systems and applications, we focus on giving the accreditor the assurance they need when developing new applications and systems. A framework has been produced by utilising the Open Web Application Security Project's (OWASP) Application Security Verification Standard (ASVS).This framework will allow security and Agile to work side by side and produce secure code.

Wireless sensor networks (WSNs) consist of battery-powered nodes equipped with specific sensors that collect appropriate information and transmit it wirelessly to a central base-station, which stores the received data for future processing or uses it dynamically for monitoring, control or other purposes. Environmental conditions inside a greenhouse can be quite extreme, with high values of temperature and relative humidity and long periods of exposure of the sensor nodes to high solar radiation intensities, which can affect the performance and quality of sensing information of WSNs. In addition, the metallic structure of the greenhouse and the canopy of the cultivated plants also affect WSN operation properties. In this work, the effects of real greenhouse conditions on the reliability of environmental monitoring using a WSN are investigated. Specific issues affecting the performance and accuracy of the WSN are identified and appropriate solutions are proposed. A prototype WSN is developed and installed inside a greenhouse in order to investigate the effects of all these parameters to the operation reliability of the network and assess its performance and the feasibility of possible future operation in a commercial greenhouse. The measured variables are air temperature, relative humidity and radiation intensity. Several experiments are conducted, trying to identify specific problems concerning the accuracy of the measured variables as influenced by specific parameters, as well as the effects of the environmental conditions inside the greenhouse in the operational performance of the WSN.