Papers by Keyword: Stabilisation

Abstract: Accumulation of spent garnet the world over poses a threat to the environment as it can cause water pollution when it enters waterways during flooding or runoff. This study summarizes potential solidification of spent garnet in concrete and the use of magnesia cement to stabilize the heavy metals in the concrete. The concrete will then be able to be used for construction purposes. The research was conducted in two phases. The first phase was preparing different percentages of spent garnet mortar at 0%, 10%, 20% and 30% and cured for 28 days. The compressive strength and density of the spent garnet mortar in 100x50 mm samples was compared against those of sand mortar. 10% application obtained the highest strength of 15.97N/mm². The second phase was preparing another set of mortar mix with 10% spent garnet and 5%, 10%, 15% of magnesia cement. The mortars were cured in distilled water and the results shown that 28 Days strength for 90:10, OPC: MgO ratio was able to achieve 21.4 N/mm². This ratio also shown recommendable low leaching of heavy metals.

Abstract: The phase transformation of zirconia from monoclinic to tetragonal polymorph at room temperature under mechanical processing has been a subject of a great interest due to technological importance of this material. Mechanism of this transformation has been widely investigated and plenty of explanation theories of zirconia stabilisation have been developed as well. This article critically reviews the systematic development regarding this transformation under mechanical processing and includes the summarised results of key-publications on this topic.

Abstract: Most often observation with a thermal camera is not static; the platform on which the surveillance equipment is mounted is affected both by motor vehicle exterior vibrations and amplitudes of the movement in field. In this paper a case study is shown starting from some tests made on a moving boat and a visual method to analyze the motion is presented. Some images acquired in real time are fast and automatic analyzed using NIVision software to quantify the random and the sinusoidal motion made by the motor vibrations and the motion of the platform. Due to this phenomenon the images seems to be blurred but this blurring can be anticipated and avoided through a proper design of platform stabilisation if the motion parameters are known.

Abstract: Sludge from tannery was solidified and stabilized by using lime, PFA and cinder as the solidifying agents，investigation of solidifying agents affect toxic heavy metals in tannery sludge and the optimum conditions of sludge solidification/stabilization were analyzed. The results showed that under the dosage of lime, PFA and cinder were 0.12kg/kg, 0.02kg/kg and 0.08kg/kg respectively, and curing time was 6 days, the compressive strength of the solidified sludge block reached 884KPa while the moisture content of the solidification block was 30.2%，which met with the standards of landfill. Compared with the untreated tannery sludge，the concentration of Cu、Pb、Zn、Ni and COD of the leaching from the sludge solidification block was reduced by 92.1%、96.7%、92.8%、88.9% and 75.9% respectively，the Cr、Cd、and Mn were undetectable.When lime and PFA ratio was 6:1, the solidified block have good synergistic solidification effects.

Abstract: In this paper, an eight-node solid hybrid-stabilized element for general piezoelectric laminate plate analysis is formulated based on the electromechanical Hellinger-Reissner functional. The independent field variables in the functional include the displacement, electric potential, stress and electric displacement. The non-constant electromechanical stress modes are contravariant in nature and chosen to be orthogonal with respect to the constant ones. The othogonality and the practice put forward in the admissible matrix formulation allow the electromechanical flexibility matrices to be block diagonal. As a result, the computational cost for inverting the electromechanical flexibility matrices can be greatly reduced. Numerical examples indicate that the proposed hybrid piezoelectric element is more accurate than their conventional counterpart.

Abstract: Stabilization effect of sodium phosphate on crystalline phase and crystal shape of hemihydrate calcium sulfate whiskers was investigated. Morphology, thermal stability and phase composition of stabilized hemihydrate calcium sulfate whiskers were characterized by means of SEM, DSC-TG and XRD respectively. Results indicated that crystalline shape of hemihydrate calcium sulfate whiskers could be invariable in two hours at 100 °C with addition of 0.10 wt % sodium phosphate for 20 min. Meanwhile sodium phosphate had a good effect on whiskers morphology stabilization.

Abstract: Based on Lyapunov stability theorem, a common adaptive strategy was designed for a common class of chaotic systems with uncertain parameters. And the discuss on the sign of unknown parameters were avoided because of the adopting of a novel kind of adaptive weight turning law. At last, the convergence time was analyzed to provide a dynamic information for system users

Abstract: The stabilization problem of a system without parameter uncertainties can always be transferred to a tracking problem if it is no need to consider the robustness requirement of a system. But those two questions are not the same for a missile control systems. In this paper, the uncertainties of parameters are considered, and we found that the stabilization problem can not be transferred to a tracking problem.

Abstract: In this paper, the stabilization problem is studied by using multiple Lyapunov function techniques for a class of discrete-time switched linear singular (DSLS) systems. The existing criteria of stability for continuous-time switched singular systems are extended into DSLS systems. Then, a hybrid switching law is designed based on a partition of state space by using S-procedure method.

Abstract: Opto-eletrical stabilization/tracking device has the precision request to improve the stabilization/tracking accuracy due to its wide use on mobile measurement. The paper firstly sums up the error sources based on the system principle of stabilization and tracking, and expatiates the effect of some error items including disturbance moment, geometrical error, and assembling error of gyro etc. Furthermore, according as the probability theory, the paper expresses the comprehensive accuracy uniformly, and obtains the evaluation method of device accuracy. Finally, it gives the example of evaluation on the direct stabilization/tracking device. The research may be useful to the error estimation during system’s design phase, but also system optimization of performance, error compensation.