This compilation opens with a study wherein investigations are conducted on a single cylinder four-stroke common rail direct injection conventional diesel engine using a combination of biodiesels derived from safflower oil methyl ester and dairy scum oil methyl ester in equal ratio. Another study focuses on the effect an internal jet piston provides on the piston surface with varied numbers of holes (2 and 4). A comprehensive overview of solid propellant combustion models and numerical simulations is summarized in an effort to determine an exact propellant burning rate under different operating conditions. The authors demonstrate how advanced mesh morphing based on radial basis functions can be used to update the shape of a component acting directly on its computational mesh. Following this, a new framework is presented for estimating the level of additive white Gaussian noise occurring in a noisy image, investigating the trailing singular values to infer the noise level. The detection technology of fluorescence lidar for biological aerosol is also studied, exploring this technique according to the dependency relation between the intensity and relative content of atmospheric biological aerosol fluorescence. In order to overcome the problem of high transmission loss in visible light communication systems, the authors propose a novel design for a 1×4 optical demultiplexer based on the multimode interference in a slot waveguide structure that operates at 547, 559, 566 and 584 nm. A literature review concerning 3D printing models in neurosurgery is performed, offering a new way to approach cerebral pathologies. The closing study discusses the flux-corrected transport algorithm and presents simulation results from several strong shock problems, including benchmark problems as well as impact-generated or explosive-driven shock propagation problems.