Yongjie Zhang¹, Boyle C. Cheng², Changho Oh¹, Jessica L. Spehar², James Burgess³

CMES-Computer Modeling in Engineering & Sciences, Vol.29, No.2, pp. 55-62, 2008, DOI:10.3970/cmes.2008.029.055

Abstract The spinal column plays a vital biomechanical role in the human body by providing structural support and facilitating motion. As degenerative changes occur in the spine, surgical treatment may be necessary in certain instances. Such treatments seek to address pain, frequently through the restriction of spinal motion. Traditional spinal implant devices are designed to restrict the motion of a functional spinal unit (FSU) but newer device designs allow for semi-constrained motion such as spinal arthroplasty devices. In this study, a sequence of fluoroscopic imaging data was recorded during the flexibility protocol with an interspinous process… More >

H.M. Lee¹, H.S. Park^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.29, No.1, pp. 29-44, 2008, DOI:10.3970/cmes.2008.029.029

Abstract This paper presents a computational model to estimate deformed shapes of beam structures using 3D coordinate information from terrestrial laser scanning (TLS). The model is composed of five components: 1) formulation of polynomial shape function, 2) application of boundary condition, 3) inducement of compatibility condition, 4) application of the least square method and 5) evaluation of error vector and determination of reasonable polynomial shape function. In the proposed model, the optimal degree of polynomial function is selected based on the complexity of beam structures, instead of using a specific degree of polynomial function. The chosen More >

Sayavur I. Bakhtiyarov¹, Dennis A. Siginer²

FDMP-Fluid Dynamics & Materials Processing, Vol.4, No.3, pp. 163-184, 2008, DOI:10.3970/fdmp.2008.004.163

Abstract This article has no abstract. More >

Chein-Shan Liu¹

CMC-Computers, Materials & Continua, Vol.8, No.1, pp. 1-16, 2008, DOI:10.3970/cmc.2008.008.001

Abstract In the present work we study numerical computations of inverse thermal stress problems. The unknown boundary conditions of an elastically deformable heat conducting rod are not given a priori and are not allowed to measure directly, because the boundary may be not accessible to measure. However, an internal measurement of temperature is available. We treat this inverse problem by using a semi-discretization technique, of which the time domain is divided into many sub-intervals and the physical quantities are discretized at these node points of discrete times. Then the resulting ordinary differential equations in the discretized More >

Chein-Shan Liu^1,2

CMC-Computers, Materials & Continua, Vol.7, No.2, pp. 81-96, 2008, DOI:10.3970/cmc.2008.007.081

Abstract We consider an inverse problem for estimating an unknown heat conductivity parameter α(t) in a heat conduction equation T_t(x,t) = α(t)T_xx(x,t) with the aid of an extra measurement of temperature gradient on boundary. Basing on an establishment of the one-step Lie-group elements G(r) and G(l) for the semi-discretization of heat conduction equation in time domain, we can derive algebraic equations from G(r) = G(l). The new method, namely the Lie-group estimation method (LGEM), is examined through numerical examples to convince that it is highly accurate and efficient; the maximum estimation error is smaller than 10^-5 for smooth parameter and More >

Britton E. Tisdale¹, D. Robert Siemens¹, John Lysack², Robert L. Nolan², James W. L. Wilson¹

Canadian Journal of Urology, Vol.14, No.2, pp. 3489-3492, 2007

Abstract Objectives: To correlate the measured dimensions of urinary stones from spiral non-contrast computerized tomography (CT) with that of plain radiography (KUB).
Methods: The transverse diameter as reported on CT was compared to the measured transverse diameter on KUB for 61 stones. The transverse and craniocaudal dimensions on CT were then re-measured for 30 urinary stones and again compared to the re-measured values for KUB. The craniocaudal dimension on CT was determined by measuring the stone on reconstructed coronal CT images. Measurements between imaging modalities were blinded and performed consecutively by a dedicated investigator.
Results: The mean transverse… More >

Song-Jeng Huang¹, Yan-Fu Liu²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.4, No.3, pp. 187-194, 2007, DOI:10.3970/icces.2007.004.187

Abstract A digital shearographic (DS) technique is a tool well-suited for precision strain measurement and is a nondestructive testing technology. But the fringe patterns of shearography are not so clear. A phase-shifting technique is incorporated into DS and demonstrated to yield fringe patterns with good quality. The major purpose of this study is to produce a measuring system of digital phase-shifting shearography (DPSS) to measure out-of-plan strain of sandwich plate with fully-potted insert. The system mainly includes piezoelectric transducer, servo controller, Michelson shearing mechanism, image processing system and loading system. The Macy algorithm is used for More >

A. Sinha Roy^*, K. West^†, R. S. Rontala¹, R. K. Greenberg², R. K. Banerje^1,‡

Molecular & Cellular Biomechanics, Vol.4, No.4, pp. 211-226, 2007, DOI:10.3970/mcb.2007.004.211

Abstract Interventional treatment of aortic aneurysms using endovascular stentgrafting is a minimally invasive technique. Following device implantation, transient drag forces act on the stentgraft. When the drag force exceeds the fixation force, complications like stentgraft migration, endoleaks and stentgraft failure occur. In such a scenario the device becomes unstable, causing concern over the long-term durability of endovascular repairs. The objective of this study is: 1) to measure the drag force on iliac limb stentgraft, having a distal diameter that is half the size of the proximal end, in an in vitro experiment; 2) to calculate the drag… More >

A.Kurenkov¹, A.Thess², H.Babovsky³

FDMP-Fluid Dynamics & Materials Processing, Vol.2, No.1, pp. 47-58, 2006, DOI:10.3970/fdmp.2006.002.047

Abstract A possibility for the determination of the interface between two electrically conducting fluids in cylindrical geometry is presented. The fluids with different conductivities are situated in an infinite cylinder. Along the axis of the cylinder a homogeneous electrical current is applied. The perturbation of the interface leads to an inhomogeneous electrical current and, therefore, results in an electrical potential change in the fluids and a magnetic field modification outside the fluids. The dependence of the electrical potential on the interface shape is obtained analytically. The interface profile is then recovered from data of the electrical More >

Anna R. Gagliardi¹, Neil Fleshner², Bernard Langer³, Hartley Stern³, Adalsteinn D. Brown⁴

Canadian Journal of Urology, Vol.12, No.5, pp. 2808-2815, 2005

Abstract Objectives: There is evidence of variation in both the processes and outcomes of prostate cancer care, resulting in possible harm to patients and increased costs to the health system. Care could be improved by first identifying critical, measurable indicators that correlate with quality of care. This work was conducted to develop indicators of prostate cancer care using a modified three-step Delphi approach.
Methods: A 17-member multidisciplinary panel reviewed potential indicators extracted from the medical literature through two consecutive rounds of rating followed by consensus discussion. The panel then prioritized the indicators selected in the previous two rounds.
Results:… More >