the present sought to draw a comparison between model predictive control performance and two other controllers named simple pi and selective pi in controlling large-scale natural gas transport networks. a nonlinear dynamic model of representative gas pipeline was derived from pipeline governing rules and simulated in simulink® environment of matlab®. control schemes were designed to provide a s...

We modified a 2-bend cystotome for continuous curvilinear capsulorhexis (CCC) in manual or phacoemulsification cataract surgery to improve the safety and ease of performance. A 26G needle was converted into a cystotome with 3 bends. In this retrospective study, the performance of modified 3-bend cystotome was compared with conventional 2-bend cystotome. During cataract surgery, in the 3-bend cy...

in this paper, the behaviour of buried pipelines under the effect of propagation of seismic waves and faulting is studied seperately. the stability of this type of structure was first studied by using three different methods proposed by newmark-hall, kenndey et al. and wang - yeh under the effect of ground faulting. by parametric study, the effect of soil types, size of pipeline, depth of embed...

Offshore pipelines used for oil and gas transportation are often buried to avoid damage from fishing activities and to provide thermal insulation. Thermal expansion and contraction of the pipeline during operation can lead to lateral or upheaval buckling. A safe buried pipeline design must take into account a reliable evaluation of soil uplift resistance and pipe embedment depth. While the cost...

In this work, using the scattering matrix method, we have investigated the transmission coefficients and the thermal conductivity in a double-bend waveguide structure. The transmission coefficients show strong resonances due to the scattering in the midsection of a double-bend structure; the positions and the widths of the resonance peaks are determined by the dimensions of the midsection of th...

A simultaneous embedding with fixed edges (SEFE) of two planar graphs R and B is a pair of plane drawings of R and B that coincide when restricted to the common vertices and edges of R and B. We show that whenever R and B admit a SEFE, they also admit a SEFE in which every edge is a polygonal curve with few bends and every pair of edges has few crossings. Specifically: (1) if R and B are trees ...

A three-dimensional grid-drawing of a graph represents the vertices by distinct points in Z (called grid-points), and represents each edge as a polyline between its endpoints with bends (if any) also at gridpoints, such that distinct edges only intersect at common endpoints, and each edge only intersects a vertex that is an endpoint of that edge. This topic has been previously studied in [1–5]....