Vincenzo Gulizzi^1,2, Piervincenzo Rizzo^2,3, Alberto Milazzo⁴

Structural Durability & Health Monitoring, Vol.10, No.1, pp. 19-54, 2014, DOI:10.3970/sdhm.2014.010.019

Abstract The electromechanical impedance (EMI) method is one of the many nondestructive evaluation approaches proposed for the health monitoring of aerospace, civil, and mechanical structures. The method consists of attaching or embedding one or more wafer-type piezoelectric transducers (PZTs) to the system of interest, the host structure, and measuring certain electrical characteristics of the transducers. As these characteristics are also related to the impedance of the host structure, they can be used to infer the mechanical properties of the monitored structure. In the study presented in this paper, we utilize the EMI to monitor the quality… More >

Salman A. Albinali¹, David R. Jacques²

Structural Durability & Health Monitoring, Vol.10, No.1, pp. 1-17, 2014, DOI:10.3970/sdhm.2014.010.001

Abstract An analytic approach to exploring the tradespace associated with Structural Health Monitoring (SHM) systems is presented. Modeling and simulation of the life cycle of a legacy aircraft and the expected operational and maintenance events that could occur is shown. A focus on the SHM system detection of a significant crack length and the possibility of False Alarm (FA), miss detection and mishap events is investigated. The modeling approach allows researchers to explore the tradespace associated with safe and critical crack lengths, sensor thresholds, scheduled maintenance intervals, falsely triggered maintenance actions, and mishaps due to missed… More >

Y. L. Liu¹, N. Hu², H. Xu³, H. Ning¹, L. K. Wu¹

CMC-Computers, Materials & Continua, Vol.40, No.1, pp. 1-20, 2014, DOI:10.3970/cmc.2014.040.001

Abstract A real-time monitoring technique for local plasticity using Lamb waves was developed. Tensile test of a thin aluminum plate with a circular hole where high stress concentration was induced was conducted to verify this technique. During the tensile test, a series of wave signals passing through the local plastic region were collected using a directional actuator/sensor set to monitor plasticity evolution. A pulse compression technique was used to process the wave signals. With the increase of tensile stress in the specimen, the amplitude changes of S₀ and A₀ modes were obtained and the difference of Lamb… More >

Hui ZHAO^1,2, Fan ZHANG^1*, Ling LI¹, Pingang HE¹, Yuzhi FANG¹

BIOCELL, Vol.37, No.3, pp. 77-83, 2013, DOI:10.32604/biocell.2013.37.077

Abstract The human neuroblastoma SH-SY5Y cell line has been used as a model to study mechanisms of neurotransmitter release. In order to study the mechanism of SH-SY5Y single cell exocytosis stimulated by different stimulants, including high K+, 3-(1-nitroso-2-pyrrolidinyl) pyridine and nicotine, a type of indium tin oxide (ITO) micro-pore electrode was used to obtain the corresponding amperometric response time. When the cell is stimulated by 0.1 M K+ , almost immediate exocytosis could be detected, due to the rapid depolarization of cell membrane. However, the stimulations with 1 mM nicotine and 3-(1-nitroso-2-pyrrolidinyl) pyridine result in a More >

Ben Chekroun K¹, A Moumen¹, N Rezzoum², E Sánchez³, M Baghour¹

Phyton-International Journal of Experimental Botany, Vol.82, pp. 31-34, 2013, DOI:10.32604/phyton.2013.82.031

Abstract The Aquatic system contamination by organic pollutants and heavy metals is one of the most serious problems that might face the environment and organisms as a whole. Interestingly, the accumulation of these pollutants is due to the anthropogenic activity, namely the intensive use of fertilizers to obtain high yields in crop production. In this paper, we compared the levels of chlorophylls, proteins, dry weight and sucrose in some red (Alsidium sp. and Gracilaria sp.) and green algae (Ulva sp.) collected from Mohandis, near Kariat and Bou Areg. Our results indicate that the algae collected nearby Bou Areg, More >

V. Mallardo^1,2, M.H. Aliabadi³

Structural Durability & Health Monitoring, Vol.9, No.4, pp. 287-323, 2013, DOI:10.32604/sdhm.2013.009.287

Abstract The optimum location of the sensors is a critical issue of any successful Structural Health Monitoring System. Sensor optimization problems encompass mainly three areas of interest: system identification, damage identification and impact identification. The current paper is intended as a review of the state of the art at the year 2012 and going back to 1990. The above topics have been dealt with in separate contexts so far but they contain interesting common elements to be exploited. More >

Mehdi Mohammadpour Lima^1,2, Dane Miller¹, Jeung-Hwan Doh¹

Structural Durability & Health Monitoring, Vol.9, No.4, pp. 269-285, 2013, DOI:10.32604/sdhm.2013.009.269

Abstract Iran is located in a seismic prone region with several earthquakes occurring annually causing extensive damage to structures and infrastructure. Guilan province is located in the northern part of the country, exhibiting a large population, moderate climate and extensive river system. This region experiences high humidity, several active faults and high seismic hazard potential. This highlights the importance of an active and extensive maintenance and rehabilitation program for the bridges in this region. Structural Health Monitoring (SHM) is an engineering tool used to control changing conditions of infrastructure providing useful information for management, decision making… More >

Dongyue Gao¹, Yishou Wang¹, Zhanjun Wu¹, Rahim Gorgin¹

Structural Durability & Health Monitoring, Vol.9, No.3, pp. 233-252, 2013, DOI:10.32604/sdhm.2013.009.233

Abstract In this study, a Lamb wave-based damage extension diagnosis method to monitor the damage on typical structures of composite aircraft is proposed. First, an overview of the damage extension diagnosis method is given. In the method, probability-based damage diagnostic imaging was combined with empirical threshold value to distinguish damage location and estimate damage size in damage extension process. To validate the effectiveness of method, extension diagnosis of simulate delamination damage in typical structure on aircraft were processed. To illustrate the capability of the damage extension diagnostic method, a delamination growth monitoring experiment was performed in More >

G. Savaidis¹, M. Malikoutsakis¹, A. Jagenbrein², A. Savaidis³, M. Soare⁴, M.V. Predoi⁴, A. Soare⁴, I.C. Diba⁴

Structural Durability & Health Monitoring, Vol.9, No.2, pp. 129-154, 2013, DOI:10.32604/sdhm.2013.009.129

Abstract Development of corrosion or/and fatigue crack propagation are the most common causes of structural degradation in road and railway tank vessels. An acoustic emission based monitoring procedure in conjunction with follow-up nondestructive testing is here proposed as a promising alternative to the conventional inspection processes enabling continuous health monitoring of the tank structures. Thereby, finite element analysis taking the respective ADR and RID tank design loads into account is proposed as a capable tool to be applied in early stages of development to reveal the hot spot areas, where acoustic emission sensors have to be More >

F. Wang^1,2, D.M. Zhang^1,2,3, H.H. Zhu⁴, H.W. Huang^1,2, J.H. Yin⁵

CMC-Computers, Materials & Continua, Vol.34, No.1, pp. 63-81, 2013, DOI:10.3970/cmc.2013.034.063

Abstract This paper studies the impact of overhead excavation on an existing tunnel through both field monitoring and a full 3D numerical model. It is found that the excavation induced longitudinal heave of the tunnel is uneven with maximum heave occurring below the excavation center. Even at the same cross section, the excavation induced heave is not uniform with the most significant heave occurring at the tunnel crown. The bending moments of the tunnel lining is decreased due to the overhead excavation. The axial forces of the tunnel lining generally decrease except at the tunnel invert. More >