Let $M$ be a right module over a ring $R$, $tau_M$ a preradical on $sigma[M]$, and$Ninsigma[M]$. In this note we show that if $N_1, N_2in sigma[M]$ are two$tau_M$-lifting modules such that $N_i$ is $N_j$-projective ($i,j=1,2$), then $N=N_1oplusN_2$ is $tau_M$-lifting. We investigate when homomorphic image of a $tau_M$-lifting moduleis $tau_M$-lifting.

This note focuses on the problem of representing convex sets as projections of the cone of positive semidefinite matrices, in the particular case of sets generated by bivariate polynomials of degree four. Conditions are given for the convex hull of a plane quartic to be exactly semidefinite representable with at most 12 lifting variables. If the quartic is rationally parametrizable, an exact se...

We propose general separation procedures for generating cuts for the stable set polytope, inspired by a procedure by Rossi and Smriglio and applying a lifting method by Xavier and Campêlo. In contrast to existing cut-generating procedures, ours generate both rank and non-rank valid inequalities, hence they are of a more general nature than existing methods. This is accomplished by iteratively s...

background: manual load lifting is the most common and stressful activity that imposes high biomechanical pressures on the body, particularly on the back. diverse studies have shown that load lifting can cause work-related musculoskeletal disorders among workers. this study was conducted to assess manual lifting activity using niosh equation and wisha index and compare the results of the two me...

Motivated by the local lifting problem for Galois covers of curves, this paper investigates Galois branched covers of the open p-adic disc. Using the field of norms functor of Fontaine and Wintenberger, we show that the special fiber of a Galois cover is determined by arithmetic and geometric properties of the generic fiber and its characteristic zero specializations. As applications, we derive...

Motivated by the local lifting problem for Galois covers of curves, this paper investigates Galois branched covers of the open p-adic disc. Using the field of norms functor of Fontaine and Wintenberger, we show that the special fiber of a Galois cover is completely determined by arithmetic and geometric properties of the generic fiber and its characteristic zero specializations. As applications...

purpose: low back pain is one of the most common musculoskeletal disorders, and lifting is one of its risk factors. the activities of lumbar muscles as the main muscles involved in lifting are important with regard to identification of the allowable limits and the injury mechanisms as well as the motor control aspects. this study aimed to investigate the effects of the lifting speed on the lumb...

Freeform rational parametric curves and surfaces have been playing a major role in computer aided design for several decades. The ability to analyze local (differential) properties of parametric curves is well established and extensively exploited. In this work, we explore a different lifting approach to global analysis of freeform geometry, mostly curves, in IR and IR. In this lifting scheme, ...

The flow set with partial order is a mixed-integer set described by a budget on total flow and a partial order on the arcs that may carry positive flow. This set is a common substructure of resource allocation and scheduling problems with precedence constraints and robust network flow problems under demand/capacity uncertainty. We give a polyhedral analysis of the convex hull of the flow set wi...