BACKGROUND Robots are very useful tools in orthopedic research. They can provide force/torque controlled specimen motion with high repeatability and precision. A method to analyze dissipative energy outcome in an entire joint was developed in our group. In a previous study, a sheep knee was flexed while axial load remained constant during the measurement of dissipated energy. We intend to apply...

We present a method based on the maximum entropy principle that can re-weight an ensemble of protein structures based on data from residual dipolar couplings (RDCs). The RDCs of intrinsically disordered proteins (IDPs) provide information on the secondary structure elements present in an ensemble; however even two sets of RDCs are not enough to fully determine the distribution of conformations,...

For a crack in a structure, the crack driving force G is the reduction of the elastic energy in the structure, associated with the crack extending per unit area. In principle, G can be calculated by solving a boundary value problem. In practice, however, such a calculation is prohibitively difficult for integrated structures of complex architectures, diverse materials and small features. The ca...

We study the convergence of GMRES/FOM and QMR/BiCG methods for solving nonsymmetric Ax = b. We prove that given the results of a BiCG computation on Ax = b, we can obtain a matrix B with the same eigenvalues as A and a vector c such that the residual norms generated by a FOM computation on Bx = c are identical to those generated by the BiCG computations. Using a unitary equivalence for each of ...

stress and residual stress are the main problems in the operating performance of materials. they are the principal causes of material failure and can affect life time of component. however measurement or predictions of them are typically difficult. two common non-destructive methods, x-ray diffraction and ultrasound are not reliable methods for subsurface residual stress measurements and destru...

Prestressed Concrete Wire and Strand (PC) strands are the most used materials to introduce prestress in a Pre-Stressed Concrete (PSC) structure. However, it is difficult to evaluate the final prestress force of the PC strand after prestressing or its residual prestress force after completion of the structure on site. This impossibility to assess eventual loss of prestress of the PC strand has r...

Since prestressed concrete members rely on the tensile strength of the prestressing strands to resist loads, loss of even few them could result catastrophic. Therefore, it is important to measure present residual prestress force. Although there are some techniques for obtaining present prestress force, some problems still remain. One method is to install load cell in front of anchor head but th...

Various forms of the viscous force caused by collision-induced parallel viscous stresses within an inhomogeneous magnetized plasma are presented. New forms are proposed for initial value extended MHD codes to capture the “fast” (Braginskii) collisional viscous force effects on short time scales and multi-collisionality regime “residual” viscous forces on collision time scales and longer in axis...

welding is one of the most important assembling methods which are widely applied in different applications. in service conditions, some of the weld joints which meet defects must be repaired. the residual stresses impress the operation and efficiency of the repair weldment. in this study, the temperature and the residual stress fields were investigated by both the finite element simulation and ...