Daiki Shiozawa¹, Shiro Kubo², Takahide Sakagami², Masaaki Takagi²

CMES-Computer Modeling in Engineering & Sciences, Vol.11, No.1, pp. 27-36, 2006, DOI:10.3970/cmes.2006.011.027

Abstract The passive electric potential CT (computed tomography) method using piezoelectric film was applied to the identification of plural through cracks. The use of piezoelectric material made it possible to obtain electric potential field without applying electric current. For identification of cracks an inverse analysis scheme based on the least residual method was applied, in which square sum of residuals is evaluated between the measured electric potential distributions and those computed by using the finite element method. Akaike information criterion (AIC) was used to estimate the number of cracks. Numerical simulations were carried out on the More >

Sunil Punjabi¹, K. Muralidhar², P. K. Panigrahi²

FDMP-Fluid Dynamics & Materials Processing, Vol.2, No.2, pp. 95-106, 2006, DOI:10.3970/fdmp.2006.002.095

Abstract Convection in a differentially heated two-layer system consisting of air and water was studied experimentally, using laser-interferometry. The cavity used for flow visualization was square in cross-section and rectangular in-plan having dimensions of 447 × 32 × 32 mm³. Experiments performed over different layer thicknesses of water filled in a square cross-section cavity, the rest being air, are reported in the present work. The following temperature differences for each layer height were imposed across the hot and the cold walls of the superposed fluid layers: (i) ΔT=10K and (ii)ΔT =18 K. The present study was aimed… More >

R. Han¹, M.S. Ingber¹, H.L. Schreyer¹

CMC-Computers, Materials & Continua, Vol.4, No.3, pp. 163-176, 2006, DOI:10.3970/cmc.2006.004.163

Abstract Decohesion is an important failure mode associated with fiber-reinforced composite materials. Analysis of failure progression at the fiber-matrix interfaces in fiber-reinforced composite materials is considered using a softening decohesion model consistent with thermodynamic concepts. In this model, the initiation of failure is given directly by a failure criterion. Damage is interpreted by the development of a discontinuity of displacement. The formulation describing the potential development of damage is governed by a discrete decohesive constitutive equation. Numerical simulations are performed using the direct boundary element method. Incremental decohesion simulations illustrate the progressive evolution of debonding zones More >

L. Gornet¹, S. Marguet², G. Marckmann³

CMC-Computers, Materials & Continua, Vol.4, No.2, pp. 63-74, 2006, DOI:10.3970/cmc.2006.004.063

Abstract The purpose of the present study is to determine the components of the effective elasticity tensor and the failure properties of Nomex^® honeycomb cores. In order to carry out this study, the NidaCore software, a program dedicated to Nomex®Cores predictions, has been developed using the Finite Element tool Cast3M-CEA. This software is based on periodic homogenization techniques and on the modelling of structural instability phenomena. The homogenization of the periodic microstructure is realized thanks to a strain energy approach. It assumes the mechanical equivalence between the microstructures of a RVE and a similar homogeneous macroscopic volume.… More >

Shen Yubin¹, Xie Huicai^1,2, Den Wei¹

CMC-Computers, Materials & Continua, Vol.3, No.2, pp. 49-54, 2006, DOI:10.3970/cmc.2006.003.049

Abstract Bonding an overlay of new concrete onto the damaged concrete is a usual repair method. Because of the different shrinkage rate of the new and old concrete, restrained shrinkage cracks will appear in the new concrete. The cracks will reduce durability and strength of the repaired structure. A new repair method using an interface layer of carbon fiber reinforced cement mortar between new and old concrete was developed in this paper. The new method was found to be very effective in reducing shrinkage cracking of repaired beams and slabs. Comparing with normal repaired beams, the More >

Lingfei Gao¹, Xiaoping Zheng^1,2, Zhenhan Yao¹

CMC-Computers, Materials & Continua, Vol.3, No.1, pp. 25-36, 2006, DOI:10.3970/cmc.2007.003.025

Abstract A general numerical approach is developed to model the elastic behaviours and failure processes of heterogeneous materials. The heterogeneous material body is assumed composed of a large number of convex polygon lattices with different phases. These phases are locally isotropic and elastic-brittle with the different lattices displaying variable material parameters and a Weibull-type statistical distribution. When the effective strain exceeds a local fracture criterion, the full lattice exhibits failure uniformly, and this is modelled by assuming a very small Young modulus value. An auto-select loading method is employed to model the failure process. The proposed More >

F. Hérodin, P. Thullier, D. Garin, M. Drouet

European Cytokine Network, Vol.16, No.2, pp. 104-116, 2005

Abstract Nonhuman primates have been used for biomedical research for several decades. They have proved to be models that are relevant to humans because of the high level of gene homology which underlies physiological and biochemical similarities. The similarity of monkeys to humans has been used to investigate pathophysiological mechanisms in hematology, immunology and virology. New therapeutic procedures can be assessed in primates by using materials, in particular pharmacological reagents, and methods designed for humans. The relevance of these models also relies on the use of species-specific pathogens and the availability of recombinant, homologous cytokines. The… More >

Judd W. Moul¹, Fred Saad²

Canadian Journal of Urology, Vol.12, Suppl.3, pp. 25-27, 2005

Abstract We currently lack a prospective, randomized, multicenter trial, to reassure low-risk prostate cancer patients, especially younger ones, that watchful waiting is a legitimate treatment. To better manage these patients, we need to: first, confirm that the patient has low-risk prostate cancer; second, adapt the treatment to the risk (i.e., if therapy is chosen over watchful waiting, it should be monotherapy not multiple therapy); third, be aware of age migration; fourth, know that radical prostatectomy and radiation were shown to be very effective for these patients at 10-year follow-up; and lastly, make an effort to better More >

Laurence H. Klotz

Canadian Journal of Urology, Vol.12, Suppl.3, pp. 21-24, 2005

Abstract Background: Many newly diagnosed patients with prostate cancer have "good risk" disease. The challenge is to identify the minority of these patients with aggressive disease and offer them curative treatment, while sparing the remainder the morbidity of unnecessary treatment.
Purpose: To examine the results of active surveillance with selective delayed intervention in good risk prostate cancer patients.
Materials and methods: This was a prospective phase II study of active surveillance of 299 patients. Eighty percent (239 patients) met the criteria for good risk disease: PSA < 10 ng/mL, Gleason ≤ 6, T ≤ 2a. Twenty percent of patients,… More >

William A. Gourlay¹, Lynn Stothers², Li Liu^1,3

Canadian Journal of Urology, Vol.12, No.1, pp. 2511-2520, 2005

Abstract Introduction: Live donor kidney transplantation (LDKT) is both medically and economically superior to cadaver kidney transplantation in the treatment of patients with chronic renal failure. Unfortunately, fewer than 50% of patients on the transplant waiting list have a relative or friend who contacts the transplant program about possible donation. We hypothesized that both the potential recipient and potential donor have identifiable and modifiable characteristics that contribute to the likelihood of a live donor transplant.
Materials and methods: Specifically-designed and validated questionnaires addressing personal characteristics, knowledge and beliefs about LDKT were mailed to patients who had previously received… More >