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Many conventional methods for controlling greenhouse climate are not effective since they are either based on an on-off control method or a proportional control method. As a result, losses in energy, labor, and productivity occur. To maintain a steady climate, an intelligent greenhouse climate controller was designed using fuzzy logic programming. This fuzzy logic program controller is based on the Mamdani controller in MATLAB software. The intelligent controller described in this paper effectively controls factors affecting the greenhouse climate by monitoring and adjusting the thermal system, ventilation-humidification system, thermal shading system, CO2 generation system, forced ventilation system and performance of system. An interactive graphical user interface was developed to test the controller performance manually. We determined that this intelligent controller is very user friendly, easy to design, highly adaptable, and quick performing, and takes few kilobytes of memory space.

Purpose The present work aims in presenting the energy absorbing capability of different combination stacking of multiple materials, namely, Vero White and Tango Plus, under static and dynamic loading conditions. Design/methodology/approach Honeycomb structures with various multi-material stackings are fabricated using PolyJet 3D printing technique. From the static and dynamic test results, the structure having the better energy absorbing capability is identified. Findings It is found that from the various stacking combinations of multiple materials, the five-layered (5L) sandwich multi-material honeycomb structure has better energy absorbing capability. Practical implications This multi-material combination with a honeycomb structure can be used in the application of crash resistance components such as helmet, knee guard, car bumper, etc. Originality/value Through experimental work, various multi-material honeycomb structures and impact resistance of single material clearly indicated the inability to absorb impact loads which experiences a maximum force of 5,055.24 N, whereas the 5L sandwich multi-material honeycomb structure experiences a minimum force of 1,948.17 N, which is 38.5 per cent of the force experienced by the single material. Moreover, in the case of compressive resistance, 2L sandwich multi-material honeycomb structure experiences a maximum force of 5,887.5 N, whereas 5L sandwich multi-material honeycomb structure experiences a minimum force of 2,410 N, which is 40.9 per cent of the force experienced by two-layered (2L) sandwich multi-material honeycomb structure. In this study, the multi-material absorbed most of the input energy and experienced minimum force in both compressive and impact loads, thus showing its energy absorbing capability and hence its utility for structures that experience impact and compressive loads. A maximum force is required to deform the single and 2L material in terms of impact and compressive load, respectively, under maximum stiffness conditions.

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Nomenclature  is Fluid Density, kg/m 3 ; E is Energy, J; p is Pressure, Pa; keff is Effective Conductivity, W/(m⋅K); T is Temperature, K; h is Sensible Enthalpy, J/kg; j J is Diffusion Flux, mol/(m 2 s); eff τ is Effective Viscous Stress N/m 2 ; V is Velocity Vector, m/s; Sh is Heat Source, J; qout,k is Energy Flux leaving the surface, J; k is Emissivity of the Surfaces, J/m 2 ;  is Stefan Boltzmann Constant; Tk is Temperature of the area, K; k is Density of the area, kg/m 3 ; qin,k is Energy Flux incident on the surface, J. Subscripts: eff -Effective; jindex of coordinate; hheat; ksurface.