This research investigated the latent heat and energy storage of lightweight concrete containing high contents of phase change material (PCM) (up to about 7.8% by weight of concrete). PCM -Polyethylene Glycol (PEG) with a fusion temperature of approximately 42-46˚C was impregnated into porous lightweight aggregates up to 24% by weight. The PCM aggregates were then used to replace normal lightweight aggregate at a rate of 0, 25, 50, 75 and 100% by volume. The samples were subjected to series of experiments such as compressive strength (EN12390-3 2002), flexural strength (ASTM C78), thermal conductivity 1

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Flexible structures have been increasingly utilized in many applications because of their light-weight and low production cost. However, being flexible leads to vibration problems. Vibration suppression of flexible structures is a challenging control problem because the structures are actually infinite-dimensional systems. In this paper, an adaptive control scheme is proposed for the vibration suppression of a piezo-actuated flexible beam. The controller makes use of the configuration of the prominent proportional-integral-derivative controller and is derived using an infinite-dimensional Lyapunov method. In contrast to existing schemes, the present scheme does not require any approximated finite-dimensional model of the beam. Thus, the stability of the closed loop system is guaranteed for all vibration modes. Experimental results have illustrated the feasibility of the proposed control scheme.

This paper presents an application of fractional‐order control to industrial electrohydraulics. An optimization based frequency domain approach is used to obtain a fractional‐order proportional‐integral controller for force control of an electrohydraulic actuator. The controller is designed to have a feature of robustness to gain variations with the step responses exhibiting an iso‐damping property. In practice, the gain variations are due to the changes in the environment or the load's force interacting with the actuator. Results of real life experiments demonstrate the effectiveness of the controller.

In this study, the thermal storage properties of lightweight concrete incorporating two types of phase change materials (PCM) with two different fusion points were investigated. Two types of PCM, polyethylene glycol (PEG) and paraffin (PRF), were impregnated into porous aggregates using high temperatures. The PCM aggregates were mixed with concrete at different proportions of PEG/PRF aggregates from 0/100 to 100/0 with 25% intervals. The experimental series consisted of thermal property tests (such as thermal conductivity, specific heat, and latent heat), and some basic properties (such as compressive strength, density, water absorption, and abrasion resistance). The results showed that incorporating PCM aggregates into lightweight concrete helped increase the workability, lower the moisture absorption, and increase the mechanical properties. For thermal properties, both thermal conductivity (k) and specific heat were found to depend strongly on the state of PCM. The latent heat of lightweight concrete with PCM aggregates in hybrid form were found to be higher than that of single type PCM aggregates.

Recently, the concept of feedback passivity-based control has drawn attention to chaos control. In all existing papers, the implementations of passivity-based control laws require the system states for feedback. In this paper, a passivity-based control law which only requires the knowledge of the system output is proposed. Simulation results are provided to show the effectiveness of the proposed solution.

Pest management, based on biological control, has drawn attention from several research groups, due to the exclusion of chemical pesticides, which have debilitating outcomes, both on the environment and human health. Biological pest control policies have been determined using the model-based control approach. In this study, the tensor product model transformation (TPMT) was applied to model the nonlinear dynamic of the biological pest control system. Consequently, the feedback control law representing the biological pest control policy was synthesized based on LMI. Under the designed controller, the pest population was regulated based on the desired level. The simulation of the biological pest control system was presented to confirm the performance of the designed control law. It is evident, that the feedback control method based on TPMT can be employed appropriately, in this application.