Additive manufacturing (AM) is being used more widely because of the simplicity of the operating procedures. It decreases material consumption during part production and eliminates material waste. Fused deposition modeling (FDM), a well‐known AM process, uses thermoplastic polymer as a feedstock to manufacture the end design. Pure thermoplastic‐based products are still utilized as prototypes in several sectors due to their lack of strength and durability. This problem has been solved by strengthening the thermoplastics by adding a reinforcing element. Composites are made of polymers and various constituents known as reinforcing components. This article overviews natural reinforced polymer composites used in the FDM process. Mechanical and Thermal properties are presented based on natural filler percentage, and this article only considered natural composite filaments for the FDM process.

The current research work on the effect of exhaust gas recirculation on the diesel engine for the analysis of performance and emission characteristics with corn oil methyl ester blends. The engine was tested with three fuels are 100diesel, 20B (20%COME + 80% Diesel) and 40B (40%COME + 60% Diesel) with EGR condition of 0% and 20% rate. The engine was evaluated with performance characteristics such as thermal efficiency, brake specific fuel consumption, exhaust gas temperature and emissions such as carbon dioxide, hydrocarbon and oxides of nitrogen. The analysed results of the brake thermal efficiency was reduced with increased brake specific consumption and the exhaust emissions are decreased with increase of biodiesel blend and increased EGR rate.

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Original scientific paper Linear time invariant discrete systems can be described by constant coefficient linear difference equations. These equations can be easily transformed into the function of the complex variable by the z transform method. Two triangular matrices are formed with the help of the coefficients of system characteristics equation along with the minimal shifting of coefficients either left or right and elimination of coefficient method. A single square matrix is constructed by adding the two triangular matrices. The proposed method of construction of square matrix consumes less arithmetic operations like shifting and eliminating of coefficients, when compared to the construction of Square matrix by Jury's and Hurwitz matrix method. This Square matrix is used for testing the sufficient condition utilising Jury's Inner determinant procedure. Further one more necessary condition is also suggested along with Jury's conditions for stability. Illustrations are also included to show the applicability of the proposed scheme. Also an algorithm was developed for finding the design parameter k-value which helps to design a stable Linear Time Invariant Discrete System. Keywords Odlučujući kriterij za analizu stabilnosti i konstruiranje linearnih diskretnih sustavaIzvorni znanstveni članak Linearni vremenski nepromjenljivi diskretni sustavi (Linear Time Invariant Discrete Systems) mogu se opisati jednadžbama linearne razlike konstantnog koeficijenta. Te se jednadžbe mogu lako pretvoriti u funkciju složene varijable metodom z transforma. Dvije trokutaste matrice stvorene su pomoću jednadžbe karakteristika koeficijenata sustava zajedno s minimalnim pomakom koeficijenata bilo lijevo ili desno i metode eliminacije koeficijenata. Konstruirana je jedna kvadratna matrica dodavanjem dviju trokutastih matrica. Za predloženu metodu konstruiranja kvadratne matrice potrebno je manje aritmetičkih operacija poput pomicanja i eliminiranja koeficijenata u usporedbi s konstrukcijom kvadratne matrice metodom matrice Jury i Hurwitza. Ta se Kvadratna matrica koristi za testiranje dovoljnog uvjeta postupkom određivanja unutarnje determinante Jurya. Dalje se predlaže još jedan potreban uvjet uz Juryeve uvjete stabilnosti. Dodane su i ilustracije za prikaz primjene predložene scheme. Razvijen je i algoritam za pronalaženje konstrukcijskog parametra k-vrijednosti koja pomaže u konstrukciji stabilnog Linearnog vremenski nepromjenljivog diskretnog sustava.Ključne riječi: algebarski test; analiza stabilnosti; diskretni sustavi; dovoljan uvjet; dvodimenzionalni sustavi; linearni vremenski nepromjenljivi sustavi; potreban uvjet

This technical brief proposes a new approach to multi-dimensional linear time invariant discrete systems within the unity shifted unit circle which is denoted in the form of characteristic equation. The characteristic equation of multi-dimensional linear system is modified into an equivalent onedimensional characteristic equation. Further formation of stability in the left of the z-plane, the roots of the characteristic equation f(z) =0 should lie within the shifted unit circle. Using the coefficients of the unity shifted one dimensional equivalent characteristic equation by applying minimal shifting of coefficients either left or right and elimination of coefficient method to two triangular matrixes are formed. A single square matrix is formed by adding the two triangular matrices. This matrix is used for testing the sufficient condition by proposed Jury's inner determinant concept. Further one more indispensable condition is suggested to show the applicability of the proposed scheme. The proposed method of construction of square matrix consumes less arithmetic operation like shifting and eliminating of coefficients when compare to the construction of square matrix by Jury's and Hurwitz matrix method.