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Shear properties of a honeycomb structure with zero Poisson’s ratio

Song L., Sun Y., Han Z., Wang T., Wang H., Yin C., Shen X.

Archives of Mechanics

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2023

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Vol. 75, nr 5

521--541

EN

Honeycomb structures with zero Poisson’s ratio show promising potential for application in variable-sweep wing aircraft. The shear properties of these honeycomb structures serve as a crucial indicator of their morphing capacity. This paper derives the linear and non-linear shear properties of a honeycomb structure with zero Poisson’s ratio. A modified factor is introduced to establish a relationship between the linear and non-linear shear modulus of the honeycomb structure, simplifying the calculation method of the non-linear shear modulus. The validity of theoretical predictions is then confirmed using the finite element method Furthermore, the influences of the geometric parameters on the shear properties of the honeycomb structure with zero Poisson’s ratio are investigated, highlighting the varying contributions of these cell geometric parameters to the shear properties.

2

Treatment of effluent (skim latex serum) from a rubber processing plant with Fenton’s reagent

Lim Y. P., El-Harbawi M., Yin C.

Environment Protection Engineering

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2017

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Vol. 43, nr 3

247--254

EN

The treatment effectiveness of Fenton's reagent using Fe2+catalyst to reduce chemical oxygen demand (COD) of skim latex serum and the effect of varying concentrations of H2O2, Fe2+and initial solution pH on its treatment efficiency were investigated. The highest COD removal efficiency obtained was approximately 80% at optimum conditions. The treatment required either nominal or no acidification as initial pH of serum is very close to the optimum pH = 4. COD removal increased upon increasing H2O2 and Fe2+concentrations. This study shows the suitability of using Fenton's process with H2O2and FeCh as a pre-Treatment for skim latex serum. The findings reported here represent a potentially simpler and more cost-effective alternative treatment to other treatment methods since only reagents and not capital-intensive materials (such as membrane) are required.

3

An Estimation Method of Pore Structure and Mineral Moduli Based on Kuster–Toksöz (KT) Model and Biot’s Coefficient

Peng D., Yin C., Zhao H., Liu W.

Acta Geophysica

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2016

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Vol. 64, no. 6

2337--2355

EN

Pore structure and mineral matrix elastic moduli are indispensable in rock physics models. We propose an estimation method of pore structure and mineral moduli based on Kuster-Toksöz model and Biot’s coefficient. In this technique, pore aspect ratios of five different scales from 100 to 10-4 are considered, Biot’s coefficient is used to determine bounds of mineral moduli, and an estimation procedure combined with simulated annealing (SA) algorithm to handle real logs or laboratory measurements is developed. The proposed method is applied to parameter estimations on 28 sandstone samples, the properties of which have been measured in lab. The water saturated data are used for estimating pore structure and mineral moduli, and the oil saturated data are used for testing these estimated parameters through fluid substitution in Kuster–Toksöz model. We then compare fluid substitution results with lab measurements and find that relative errors of P-wave and S-wave velocities are all less than 5%, which indicates that the estimation results are accurate.

4

Reliability and Risk Assessment of Aircraft Electric Systems

He L., Yin C., Peng W., Yuan R., Huang H.-Z.

Eksploatacja i Niezawodność

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2014

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Vol. 16, no. 4

497--506

EN

It is rather difficult in identifying the fault location and performing risk assessment for complex electronic systems. In this paper a reliability assessment method based on the interval analytic hierarchy process (IAHP) and Bayesian network is proposed to facilitate reliability and risk assessment. After considering the major fault factors, the interval eigenvector method (IEM) is also presented to assess the reliability and comprehensive weights of subsystems. The conditional probability matrices for the factors of risk are defined using an inference rule. Then an updating model of information fusion in the context of Bayesian network is established to assess the risk of system. The proposed method is demonstrated through the risk assessment of an aircraft electric system. The result of the illustrative example shows that the proposed method can not only incorporate the evidence information, but also synthesize all the historical information. A further dynamic adjustment in the safety and risk priority of control measures is quite effective to improve the reliability while mitigating the risk of the electric system.

PL

Lokalizacja uszkodzeń oraz ocena bezpieczeństwa i ryzyka w przypadku złożonych systemów elektronicznych jest zadaniem dość trudnym. W niniejszej pracy zaproponowano metodę prognozowania niezawodności opartą na procesie przedziałowej hierarchii analitycznej (IAHP), która ma na celu ułatwienie diagnozy uszkodzeń i kontroli ryzyka. Po rozważeniu głównych czynników wywołujących uszkodzenia, zaprezentowano metodę przedziałowych wektorów własnych oraz zdefiniowano, przy użyciu reguły wnioskowania, macierze prawdopodobieństwa dla czynników wpływających na bezpieczeństwo i ryzyko. Następnie, stworzono odnawialny model fuzji informacji w kontekście wnioskowania bayesowskiego służący do oceny stanu zagrożenia Udowodniono, iż włączenie wiedzy eksperckiej do dynamicznej symulacji ułatwia lokalizację uszkodzeń oraz pozwala uzyskać informacje dotyczące diagnozy uszkodzeń. Studium przypadku pokazuje, że dynamiczne dostosowanie priorytetowości związanej z bezpieczeństwem i ryzykiem stosowanych środków kontroli w sposób dość skuteczny zwiększa niezawodność przy jednoczesnym zminimalizowaniu ryzyka w złożonym systemie elektronicznym.