studying gaussian beam is a method to investigate laser beam propagation and abcd matrix is a fast and simple method to simulate gaussian beam propagation in different mediums. of the abcd matrices studied so far, reflection and refraction matrices at various surfaces have attracted a lot of researches. however in previous work the incident beam and the principle axis of surface are in parallel...

in this paper we develop a new approach for land leveling in order to improve the topology of a large area for irrigation or civil projects. the objective in proposed model is to minimize the total volume of cutting so that technical requirements of land leveling such as suitable slope and standard ratio of cutting to filling and maximum penstock point’s height are considered. we develop a warp...

saturated fat consumption increases the risk of both coronary and cancer diseases. therefore, fat reduction in uf-feta cheese (≈ 45% fdm) is favorable but, unfortunately, it has some negative effects on the texture and sensory characteristics of the cheese. in this research, response surface methodology was employed to study the probably improving effects of wpc80 (0-20 gr kg-1), lecithin (0-2 ...

oceanographic images obtained from environmental satellites by a wide range of sensors allow characterizing natural phenomena through different physical measurements. for instance sea surface temperature (sst) images, altimetry data and ocean color data can be used for characterizing currents and vortex structures in the ocean. the purpose of this thesis is to derive a relatively complete frame...

background and aims. the aim of the present study was to compare the effect of surface treatment with er; cr:yssg, nd:yag, and co2 lasers on repair shear bond strength of a silorane-based composite resin. materials and methods. sixty eight cylindrical samples of a silorane-based composite resin (filtek silorane) were prepared and randomly divided into 4 groups as follows: group 1: without surfa...

lapping is one of the most important polishing processes which can be used to fabricate flat and smooth surfaces. in this paper, the effect of lapping characteristics and mesh number of abrasive particles are studied on the surface roughness and flatness for the machining of hardened aisi 52100 rings. the most significant lapping characteristics are pressure, lap plate speed and time. scanning ...

statement of problem: in some clinical situations, repair of composite restorations is treatment of choice. improving the bond strength between one new and old composite usually requires increased surface roughness to promote mechanical interlocking since chemical bonding might not be adequate. similarly, the treatment of a laboratory fabricated resin composite restoration involves the same pro...