Resonance Y-shape Solitons and Mixed Solutions for a (2+1)-dimensional Generalized Caudrey-Dodd-Gibbon-Kotera-Sawada Equation in Fluid Mechanics

Under the well-known bilinear method of Hirota, the specific expression for N-soliton solutions of (2+1)-dimensional generalized Caudrey-Dodd-Gibbon-Kotera-Sawada(gCDGKS) equation in fluid mechanics is given. By defining a noval restrictive condition on N-soliton solutions, resonant Y-type and X-type soliton solutions are generated. Under the previous new constraints, combined with the velocity resonance method and module resonant method, the mixed solutions of resonant Y-type solitons and line waves, breather solutions are found. Finally, with the support of long wave limit method, the interaction between resonant Ytype solitons and higher-order lumps is shown, and the motion trajectory equation before and after the interaction between lumps and resonant Y-type solitons is derived.

The Sonic Resonance Method and the Impulse Excitation Technique: A Comparison Study

In this study, resonant frequencies of flexurally vibrating samples were measured using the sonic resonant method (SRM) and the impulse excitation technique (IET) to assess the equivalency of these two methods. Samples were made from different materials and with two shapes (prism with rectangular cross-section and cylinder with circular cross-section). The mean values and standard deviations of the resonant frequencies were compared using the t-test and the F-test. The tests showed an equivalency of both methods in measuring resonant frequency. The differences between the values measured using SRM and IET were not significant. Graphically, the relationship between the resonant frequencies is a line with a slope of 0.9993 ≈ 1.

3D printed Ku band cylindrical Luneburg lens

The design of the cylindrical Luneburg lens manufactured by using 3D printing facilities was presented, fabricated and experimentally verified. The two different approaches to lens parameter discretization were applied to lens design and compared. The effective dielectric permittivity of Polylactic Acid (PLA) plastic samples with different infilling percentage were estimated by a resonant method.

Development of split ring resonator for pineapple moisture content detection

Microwave resonant is one of the sensors used in characterizing the material and is also one of the most sensitive sensors for measuring dielectric properties. This project proposed the resonant method due to its accuracy and sensitivity. The split ring resonators were mounted on the fruit sample surface to observe the resonant frequency behavior, and to measure the fruit freshness. The resonator was set at 6 GHz using the FR4 lossy substrate. The findings show that the coupling distance and the ring radius have the greatest impact on preserving the resonant behavior. The fundamental of the obtained resonant frequencies was observed based on the different moisture content of the test material. The moisture level was observed at 38.2%, 54%, 69%, and 86.7%. At 86.7%, the resonant frequency has the highest shifting by shifting to the left. This shows that the larger resonant frequency change occurs when the water content is higher.

Results of modeling the dependence of the height of flexural-gravity waves in a floating plate with a sealed edge on the inclination of the bottom of the reservoir

На основании проведенных автором экспериментов по разрушению льда амфибийными судами на воздушной подушке (СВП) резонансным методом при их движении в сторону берега, их крупномасштабных моделей в полевых условиях, а также известных случаев разрушения ледяного покрова движущимися в сторону берега транспортными средствами показана возможность существенного увеличения толщины льда, разрушаемого у его береговой кромки. Приведены данные экспериментов, выполненных в опытовом бассейне на моделирующих ледяной покров упругих пленках, подтверждающие эти возможности. В работе представлены результаты моделирования зависимости высоты изгибно-гравитационных волн (ИГВ), возбуждаемых в плавающей пластине движущейся в направлении ее заделанной кромки нагрузкой, от угла наклона дна бассейна. Также приведены рекомендации по использованию наклонности дна для повышения эффективности разрушения ледяного покрова (увеличения толщины разрушаемого льда) путем возбуждения резонансных ИГВ. На основании выполненных экспериментов показано, что приближение к берегу ИГВ, возбуждаемых СВП с последующим их выходом на него, может значительно увеличить толщину разрушаемого льда за счет отрыва от берега его кромки. Отмечена возможность увеличения ледоразрушающей способности ИГВ благодаря последующим проходам судна вдоль нее из-за роста деформаций ослабленного таким образом льда, т.е повышения ледоразрушающей способности СВП. Based on the experiments conducted by the author on ice destruction by amphibious hovercraft using the resonant method when they move towards the shore, their large-scale models in the field, as well as known cases of ice cover destruction by vehicles moving towards the shore, the possibility of a significant increase in the thickness of ice destroyed at its coastal edge is shown. The data of experiments performed in the experimental pool on elastic films modeling the ice cover are presented, confirming these possibilities. The paper presents the results of modeling the dependence of the height of Flexural-gravitational waves excited in a floating plate by a load moving in the direction of its embedded edge on the angle of inclination of the pool bottom. Recommendations are also given for using the bottom slope to increase the efficiency of ice cover destruction (increasing the thickness of the destroyed ice) by exciting resonant Flexural-gravitational waves. Based on the performed experiments, it is shown that the approach to the shore of Flexural-gravitational waves excited by hovercraft with their subsequent exit to it can significantly increase the thickness of the destroyed ice due to the separation of its edge from the shore. The possibility of increasing laboratree the ability of the Flexural-gravitational waves during the next passages of the ship along it due to the growth of deformations weakened the ice.

Analysis of methods for measuring the dielectric properties of materials in the microwave range of wavelengths.

One of the modern trends in the development of communication systems, information and telecommunication systems, air traffic control systems, etc. is the transition and development of higher-frequency wavelength ranges. In this regard more and more stringent requirements (in terms of spectrum, out-of-band and spurious radio emission, and in the shape of the output signal) are imposed on radio engineering devices that transmit and receive microwave radio signals. As a result, the requirements for the design and functional features of microwave electronic devices are increasing. One of these requirements is to assess the degree of compliance with the required values of dielectric properties of materials used in the design of microwave electronic devices. This requirement is justified by the fact that the electrical parameters of such microwave devices as: strip filters, power dividers, printed antennas and others, directly depend on the dielectric properties of the materials used in their substrate designs. In this regard, three main methods have now emerged for assessing the dielectric properties of materials: the resonant method, the non-resonant method, and the free space method. Aim. The aim of this article is to carry out a comparative analysis of the known methods for measuring the dielectric properties of materials in the microwave range of wavelengths and devices for their implementation. Materials and methods. The authors of the article reviewed the scientific literature of domestic and foreign publications. Results. For each of the methods for measuring the dielectric properties of materials, their main idea, practical implementation, a mathematical model for processing experimental data and areas of application are given. The advantages and disadvantages for each of the methods for measuring the dielectric properties of materials are given too. Conclusion. The applicability of each of the considered methods depends on such factors as: the shape of the investigated dielectric material, its state of aggregation, the possibility of measuring amplitude or complex transmission and reflection coefficients, the presence of an anechoic chamber, etc.

Frequency-tunable device based on a multilayer strip-slot transition and its application for measuring the dielectric properties of materials

The paper presents the results of theoretical and experimental researches of a frequency-tunable device based on the multilayer strip-slot transition with the U-shaped slot resonator of the variable length. The application of the presented device makes it possible to implement a resonant method for measuring the dielectric properties of materials in the microwave frequency range. The numerical simulation in the rigorous formulation of the electrodynamics problem is performed for the theoretical research. The aim of the theoretical research is to determine the electrical characteristics of the multilayer strip-slot transition with the U-shaped slot resonator of the variable length. The results of numerical simulation prove the possibility of applying the multilayer stripslot transition with the U-shaped slot resonator of the variable length to implement the resonant method for measuring the dielectric properties of materials in the microwave frequency range. The experimental research is performed on the sample of the multilayer strip-slot transition with the U-shaped slot resonator of the variable length in the frequency range (850–1250) MHz. Measurements of S-parameters of the multilayer strip-slot transition with the U-shaped slot resonator of the variable length are accomplished using the vector network analyzer. The material under research is BaFe10Ti2O19. The results of theoretical and experimental researches are in good qualitative and quantitative agreement.