Using a fullwave analysis, the integral equation for unknown electric field distribution on the slot apertures of GCPW is derived. Then it is numerically solved in the space domain using the method of moments. Using derived electric field distribution and ideal transmission line theory, the discontinuity parameters of short-end and open-end GCPW are computed and compared with CPW. In addition, a comparison between the CPW and GCPW effective dielectric constant is presented.

The paper describes an investigation about the application of the new multipleimpedance DISCONTINUITIES model for optimizing profile diffuser barriers. The new MULTIPLE-IMPEDANCE DISCONTINUITIES model is much faster than the numerical method, thus it is used in an optimization process. The A-weighted insertion loss was used for the traffic noise spectrum.The result of optimization, which is done by simplex downhill method, showed that the chosen method combined with the appropriate cost function is both a fast and effective way to optimize a diffusive profiled barrier, improving the performance of the barrier in the whole frequency bandwidth of the reactive profiled barriers. The optimized barrier improves the A-weighted insertion loss of all different tested barriers including absorbent, quadratic residue sequence and random sequence barriers.The introduced optimization process in this investigation is fast, clear and flexible so that any different ribbed surfaces and dimensions utilized on any different T-profile barriers can be optimized. The parameter used to optimize is just simply the well depth sequence, which is easy to realize and practical to design.

The importance of research in crashworthiness and the post-accident behavior and efforts to improve the behavior of the structure and reduce the accelerations to the occupants with the help of energy absorbers is determined by observing the increasing statistics of vehicle accidents, including cars, trains, and airplanes. In this research, the energy-absorbing behavior of a thin wall with an aluminum rectangular section will be investigated by numerical solution in finite element method and in Abaqus software, and to improve its energy absorption parameters, DISCONTINUITIES were created on the geometry, which regularized the folding pattern. The primary research approach is to improve the energy absorption behavior without fundamentally changing the geometry. DISCONTINUITIES with different geometrical shapes, sizes, and numbers are placed in different places in the model to obtain the best energy absorption behavior. After evaluating and choosing the circular discontinuity among the other geometric shapes, for their proper placement, an initial guess of the location of the DISCONTINUITIES was considered with the help of similar research. Then, the eigenvalues of the geometry extracted from the buckling solver have been used to place and increase the number of DISCONTINUITIES.Finally, by examining 43 models with different numbers and placement of DISCONTINUITIES, a model with a 13% improvement in the CFE criterion was proposed.

To improve the procedure of ornamental stone quarries design, a research program was conducted under the title of "The Effect of DISCONTINUITIES on the design of ornamental stone quarries" at Shahrood university. In this study, IBSD or "In Situ Block Size Distribution" of rock, was considered as a parameter, which could assist the design engineer in decision making on the feasibility study procedure.Scan line sampling method was used for collecting discontinuity data while K-means method was used to cluster the DISCONTINUITIES and classify the discontinuity sets as well.Based on the above, a user friendly software named "Geoquary" was developed. Using this software the design engineer can have a three dimensional view of the sight and process the discontinuity data collected from the field and evaluate the IBSD. As the block sizes in a rock mass play an important role in the design of an ornamental stone quarry, the design engineer can make decisions about the mine, with a higher degree of confidence.

Purpose: In this paper, we investigate a class of Sturm-Liouville operators with eigenparameter-dependent boundary conditions and transmission conditions at finite interior points.Methods: By modifying the inner product in a suitable Krein space K associated with the problem, we generate a new self-adjoint operator A such that the eigenvalues of such a problem coincide with those of A.Results: We construct its fundamental solutions, get the asymptotic formulae for its eigenvalues and fundamental solutions, discuss some properties of its spectrum, and obtain its Green function and the resolvent operator.Conclusions: Three important conclusions can be drawn: (1) the new operator A is self-adjoint in the Krein space K; (2) if θi>0, i=1, m-, and ρj>0, j=1, 2, then, the eigenvalues of the problem (Equations 1 to 5) are analytically simple; (3) the residual spectrum of the operator A is empty, i.e., σr (A)=∅.

In this paper a numerical procedure is presented based on the method of least squares (MLS) to synthesize a stepline transformer to match two complex impedances over a frequency bandwith for a specified line length. First, the input impedance of a stepline terminated in a load impedance is obtained using the transmission matrices of the line sections and junction discontinuity impedances. Then, an error function is constructed as the sum of the magnitude squared of the difference between the input impedance of the stepline and the generator impedance over discrete frequencies in the desired bandwidth. The error function is then minimized with respect to the stepline characteristic impedances and also separately with respect to the stepline length. This numerical procedure serves as an effective tool for the design of transformers of complex impedances with specified lengths and frequency bandwidths and its implementation reveals uncommon and interesting transformer shapes which best realize matching conditions in the least square sense.

This paper outlines a simple technique for introducing displacements of DISCONTINUITIES into finite element computations. This method considers displacement DISCONTINUITIES existing in a continuum and could be easily added to available elastic codes. The modification induced by this technique can be contained in the load vector, so that the stiffness matrix is not altered. Besides, this method does not increase the number of degrees of freedom and, no net forces or moments are induced on the finite element mesh either.

The presence of DISCONTINUITIES such as joints, has effect on behavior of rock mass and as a result affects stability of structures built within rock mass. Therefore, it is imperative to assess the behavior of the rock mass before designing and constructing structures within it. Performing in situ tests is the most accurate method for estimating the geomechanical properties of rock masses, but it is expensive and time-consuming. As a result, researchers often decide to produce laboratory-based rock mass samples. In recent years, in rock mechanics science has been used 3D printing technology for preparation of rock samples. The objective of this research was to model DISCONTINUITIES systems within rock sample to investigate the shear behavior of jointed rock. This study started by reviewing the limitations of conventional rock mechanics tests when applied to jointed rock. Subsequently, jointed rock samples were prepared using a 3D printer. Direct shear tests were conducted on artificial samples which were designed to simulate rock mass. The results clearly demonstrate the capability of 3D printing technology to produce rock mass. It was observed that the shear strength of the 3D-printed rock samples was lower than that of intact rock samples. The use of polyvinyl alcohol materials in constructing the DISCONTINUITIES system proved to be suitable. These materials dissolve easily in water. The 3D-printed network is placed inside a mold and filled with a slurry with the appropriate ratio of water, sand and cement. This block is placed in water, resulting the network dissolve and do not influence on geomechanical parameters of sample. Furthermore, the cohesion of the rock mass was found to be directly influenced by the orientation of the DISCONTINUITIES systems. Aligning the shearing surface with the DISCONTINUITIES system reduced cohesion.