Siyuan Mei^1,2, Yingyi Chen^1,2,*, Hanxiang Qin^1,2, Huihui Yu³, Daoliang Li^1,2, Boyang Sun^1,2, Ling Yang^1,2, Yeqi Liu^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.131, No.3, pp. 1315-1335, 2022, DOI:10.32604/cmes.2022.019378

Abstract Fish behavior analysis for recognizing stress is very important for fish welfare and production management in aquaculture. Recent advances have been made in fish behavior analysis based on deep learning. However, most existing methods with top performance rely on considerable memory and computational resources, which is impractical in the real-world scenario. In order to overcome the limitations of these methods, a new method based on knowledge distillation is proposed to identify the stress states of fish schools. The knowledge distillation architecture transfers additional inter-class information via a mixed relative loss function, and it forces a lightweight network (GhostNet) to mimic… More >

Darshan Babu L. Arasu¹, Ahmad Sufril Azlan Mohamed^1,*, Nur Intan Raihana Ruhaiyem¹, Nagaletchimee Annamalai², Syaheerah Lebai Lutfi¹, Mustafa M. Al Qudah¹

CMES-Computer Modeling in Engineering & Sciences, Vol.130, No.2, pp. 633-652, 2022, DOI:10.32604/cmes.2021.016985

Abstract Stress is a normal reaction of the human organism which triggered in situations that require a certain level of activation. This reaction has both positive and negative effects on everyone’s life. Therefore, stress management is of vital importance in maintaining the psychological balance of a person. Thermal-based imaging technique is becoming popular among researchers due to its non-contact conductive nature. Moreover, thermal-based imaging has shown promising results in detecting stress in a non-contact and non-invasive manner. Compared to other non-contact stress detection methods such as pupil dilation, keystroke behavior, social media interaction and voice modulation, thermal-based imaging provides better features… More >

M. Lavella¹, T. Berruti¹

Structural Durability & Health Monitoring, Vol.5, No.4, pp. 337-350, 2009, DOI:10.3970/sdhm.2009.005.337

Abstract Results of residual stress measurements on Inconel 718 turbine components after machining are here presented. The work is focused on the experimental detection of the residual stress state produced after turning (orthogonal cutting and standard) and milling. The aim of the experimental activity was to supply an experimental data base of proved reliability for milling and turning model validation. This activity was performed inside the EU STREP project VERDI. The residual stresses were detected by means of X-ray diffraction technique. The experimental plan of measurements was performed on components worked with different working parameters (cutting velocity and feed rate) and… More >

Quang Dang^1,1, Hans Gregersen^2,2, Birgitte Duch^2,2, Ghassan S. Kassab^1,1

Molecular & Cellular Biomechanics, Vol.2, No.2, pp. 53-62, 2005, DOI:10.3970/mcb.2005.002.053

Abstract Biliary duct obstruction is an important clinical condition that affects millions of people worldwide. We have previously shown that the common bile duct (CBD) undergoes significant growth and remodelling post obstruction. The mechanical stress-strain relation is expected to change due to growth and remodeling in response to obstruction and hence pressure-overload. The objective of the present study was to characterize the material properties of the CBD of the sham group and at 3 hours, 12 hours, 2 days, 8 days and 32 days (n=5 in each group) after obstruction. The Fung's exponential strain energy function was used to relate stress… More >

Francesco Genna¹, Corrado Paganelli², Stefano Salgarello³, Pierluigi Sapelli²

CMES-Computer Modeling in Engineering & Sciences, Vol.4, No.3&4, pp. 405-420, 2003, DOI:10.3970/cmes.2003.004.405

Abstract We study the mechanical behavior of a prototype osseointegrated dental implant containing a thin internal layer, designed in such a way as to simulate the existence of the periodontal ligament (PDL). Experimental stress-strain curves suggest that the behavior of the PDL can be simulated by means of a compressible hyperelastic constitutive model, at least for short-term loading. We have adopted one such a model to describe the mechanical behavior of the internal layer in the prototype implant design, studied by means of several 3--D Finite Element analyses. The results indicate that the presence of such a nonlinear internal layer is… More >

Hui Han, Yi Wah Mak, Wei Huang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.3, pp. 85-86, 2011, DOI:10.3970/icces.2011.019.085

Abstract The root of Salvia miltiorrhiza bunge, Danshen, is a traditional Chinese herb known to prevent hypertension. However, the mechanism of how Danshen affects the mechanical properties of blood vessel is not clear. In this project, we studied the effects of Danshen on zero-stress state of rat's abdominal aorta, which is the basic configuration of blood vessel affected solely by intrinsic parameters.
Sprague Dawley rats, male, around 350g, were used. The zero-stress state of a blood vessel can be very different from the in vivo state and the no-load state of the vessel. At the in vivo state, the rat's… More >

Hui Han^∗, David C. C. Lam^†, Wei Huang^†,‡

Molecular & Cellular Biomechanics, Vol.9, No.4, pp. 295-308, 2012, DOI:10.3970/mcb.2012.009.295

Abstract The objective of our study was to study the effect of danshen, a Chinese herbal medicine known to prevent hypertension, on the zero-stress state of rat's abdominal aorta. The zero-stress state of a blood vessel represents the release of residual stress on the vessel wall, and is the basic configuration of blood vessel affected solely by intrinsic parameters. At the in vivo state, the rat's abdominal aorta was subjected to blood pressure and flow and longitudinal stress. After dissecting from the abdominal aorta, the aortic specimens were cut into small rings at no-load state, in which the internal pressure, external… More >

Wei Huang^∗,†, Yi Wah Mak^*, Peter C. Y. Chen^‡§

Molecular & Cellular Biomechanics, Vol.8, No.2, pp. 91-104, 2011, DOI:10.3970/mcb.2011.008.091

Abstract A molecular configuration tensor Pij was introduced to analyze the distribution of fibrous proteins in vascular cells for studying cells and tissues biomechanics. We have used this technique to study the biomechanics of vascular remodeling in response to the changes of blood pressure and flow. In this paper, the remodeling of the geometrical arrangement of F-actin fibers in the smooth muscle cells in rat's pulmonary arteries in hypoxic hypertension was studied. The rats were exposed to a hypoxia condition of 10% for 0, 2, 12, and 24 hr at sea level. Remodeling of blood vessels were studied at the in… More >

Xueying Huang^*, Chun Yang^†, Chun Yuan^‡, Fei Liu^‡, Gador Canton^‡, Jie Zheng^§, Pamela K. Woodard^§, Gregorio A. Sicard^¶, Dalin Tang^||

Molecular & Cellular Biomechanics, Vol.6, No.2, pp. 121-134, 2009, DOI:10.3970/mcb.2009.006.121

Abstract Image-based computational models for atherosclerotic plaques have been developed to perform mechanical analysis to quantify critical flow and stress/strain conditions related to plaque rupture which often leads directly to heart attack or stroke. An important modeling issue is how to determine zero stress state from in vivo plaque geometries. This paper presents a method to quantify human carotid artery axial and inner circumferential shrinkages by using patient-specific ex vivo and in vivo MRI images. A shrink-stretch process based on patient-specific in vivo plaque morphology and shrinkage data was introduced to shrink the in vivo geometry first to find the zero-stress… More >

Boštjan Brank¹, Adnan Ibrahimbegovic² and Uroš Bohinc³

CMES-Computer Modeling in Engineering & Sciences, Vol.33, No.1, pp. 85-108, 2008, DOI:10.3970/cmes.2008.033.085

Abstract In this work we study the accuracy of modern higher-order shell finite element formulations in computation of 3d stress state in elastic shells. In that sense we compare three higher-order shell models: (i) with seven displacement-like kinematic parameters, and (ii, iii) with six displacement-like kinematic parameters plus one strain-like kinematic parameter introduced by two different versions of enhanced assumed strain (EAS) concept. The finite element approximations of all shell models are based on 4-node quadrilateral elements. Geometrically nonlinear and consistently linearized forms of considered formulations are given. Several numerical examples are presented, where computed stresses are compared with analytical solutions.… More >