Three types of ultrawideband (UWB) antennas with triple notched bands are proposed and investigated for UWB communication applications. The consist a planar circular patch monopole antenna multiple etched slots on the and/or split ring resonators (SRRs) coupled to feed line. Good agreement is achieved between simulated measured results. These techniques significant designing narrow frequency or multiband antennas.

Using the differential evolution algorithm (DEA), low-sidelobe-level (SLL) series-fed microstrip antenna arrays of unequal inter-element spacing (IES) are investigated. The proposed design method can achieve conversion between SLL and half-power beamwidth (HPBW). constraint conditions for IES amplitude set up, element size is also taken into account in pattern function. Based on solutions from DEA, two types IES, i.e., uniform nonuniform arrays, designed, fabricated, measured. Measurement...

To satisfy certain requirements for an antenna design, many full-wave electromagnetic (EM) simulations are required, and they involve a considerable computational burden. A multibranch machine learning-assisted optimization (MB-MLAO) method is proposed to dramatically reduce the complexity in this task. Then, applied design worst case performance (WCP) searching under practical manufacturing tolerance. In conventional Gaussian process regression (GPR)-based MLAO method, lower confidence...

This work proposes a general method for establishing the lubrication analysis model of ball bearing and oil-air multiphase flow characteristics inside is revealed by CFD. Based on geometric feature, micro-clearance in chamber introduced into simulation model, complicated boundary shape developed. Meanwhile, divided hexahedron elements mesh density near contact region increased, which promotes convergence accuracy solution. Then, performance experiment conducted, demonstrate that this could...

A dual-band dual-circularly polarized (CP) antenna fed by a 3-dB substrate integrated coaxial line coupler is designed, fabricated, and measured. The proposed excited two planar L-probes that are connected to output ports of the coupler. This dual-CP effectively covers L-band 1.62 GHz S-band 2.50 GHz, respectively. Simulation measurement results show that, considering reflection coefficient, gain, axial ratio together, relative bandwidth about 10% at lower band 4% upper band. maximum...

Machine-learning (ML)-assisted antenna-array design methods suffer from a heavy computational burden. In this article, knowledge-guided active-base-element-modeling (KG-ABEM) method is proposed for practical antenna array to largely alleviate With the introduction of prior physical knowledge and trustworthy assumptions, ML only introduced scenes where analytical cannot build accurate models, achieving great efficiency accuracy improvement simultaneously compared with conventional ML-assisted...

The superjunction MOSFET power devices, such as p-n column (named SJ or CoolMOS) devices and oxide-bypassed (OB) are highly recognized for their higher blocking capability lower on-state resistance. However, the performance of is greatly handicapped due to difficulties in formation perfect charge-balanced columns by current process technology, especially with small widths voltage ratings below 180 V. OB can be an alternative this region, which utilize well established oxide thickness control...

As the element of rotary motion, evaluation hydrodynamic behavior for spiral groove conical bearing (SGCB) is related with stability multibody systems and influence cavitation on lubrication performance SGCB an important concern. This work presents a computational method design in different operation conditions, considering multi-objective analysis. With effects taken into account, calculated multiphase flow model accounting phase transition process phenomenon. Moreover, numerical results...

Abstract The seamless or incorporate design of RF filter and antenna is very important for size loss reduction in the millimeter wave wireless communication systems.Such then called as filtenna. In this article, an integrated filtenna at 37–38 GHz local‐multipoint‐distribution‐system (LMDS) based on substrate waveguide (SIW) technology presented. One slot two‐slot SIW antennas corresponding filtennas are simulated, fabricated measured. By comparing measured return radiation patterns between...

A wideband U-slot patch antenna with reconfigurable radiation pattern is investigated. The composes three patches which are one coaxial-fed driven and two parasitic located near the non-radiating edges of middle patch. One varactor diode installed in each Both beamwidth main lobe direction can be tuned by controlling direct current bias voltages diodes. presented has wide operating bandwidth 6.4% at 1.4 GHz. Its continuously changed from 60 degree to 130 its scan -20 +20 H-plane. peak gain...

The gas-lubricated thrust bearing is widely used in agriculture mechanical systems, and the groove shape plays an important role on hydrodynamic behavior of spiral-grooved (SGTB). Although may change smaller, it clear that response very sensitive to parameters. This paper proposes a computational method for analysis SGTB with gas lubricant, considering effects With compressibility taken into account, evaluation lubrication performance obtained by CFD technology. Also, simulation results are...

Printed wideband and ultra-wideband (UWB) antennas are the simple low cost electromagnetic radiator design for front-end system with low-power high-data-ratio transmissions. Antenna stable directional radiation pattern is critical to maintain link gain of wireless communication. With co-existence UWB other different systems, antenna notched band(s) an effective way suppress interference between these systems. This invited talk reviews some recent works on areas, which has been pursued by...

A wideband single-layer microstrip reflectarray is investigated. Firstly, a new dual-resonance unit cell proposed for the reflectarray, which provides an approximately linear phase response during 0-360° range. Additionally, its curves are nearly parallel within broad band, can widen bandwidth. Then, 576-element of size 12λ×12λ using designed and analyzed. Simulation results show that boresight gain 27.9 dBi 1-dB bandwidth greater than 39.78% at Q band.

A new calculation method for the equivalent width of substrate integrated coaxial line (SICL) with two dielectric layers, same height and different permittivity is proposed in this paper. The SICL approximately modeled as a rectangular (RCL) characteristic impedance using capacitance theory, weff. Lastly, was proved effectively by simulation results.

Abstract A dual‐polarised symmetrically cross‐slotted square patch (SCSSP) antenna with multimode resonance is proposed for 5G millimetre‐wave broadband applications. symmetrical cross‐slot etched on the surface to change original E‐field distribution where a whole cut into four disconnected equal parts. For both polarisations, this etching also tunes frequencies of two modes be sufficiently close each other. Therefore, can realize good impedance performance within wide designated bandwidth....

The professional technology training of student is the important objective engineering education, which could present specialized ability in future. This task conducted to evaluation teaching methods for fluid mechanics course mechanical engineering. With practice, advantage method found, and quality can be revealed by scores integrated test. improvement contribute development social. According self-assessment, effects on revealed.•The diversified understanding theory knowledge...

In the paper, a printed dual-dipole array antenna is presented. A 4-way planar SIW power divider adopted for feeding antenna. The as radiation elements which greatly improves impedance band. measured bandwidth larger than 31 % VSWR<TEX>$\leq$</TEX>1.5 operating near 14 GHz achieved and in agreement with simulated results. E-plane H-plane pattern presented paper. gain also

The professional technology training of student is the important objective engineering education, which could present specialized ability in future. This task conducted to evaluation teaching methods for fluid mechanics course mechanical engineering. With practice, advantage method found, and quality can be revealed by scores integrated test. improvement contribute development social. According self-assessment, effects on revealed. diversified understanding theory knowledge application.The...

Abstract Journal bearing is the general element in mechanical systems, which can provide rotational motion of joints. The hydrodynamic analysis model journal established and effects cavitation minuscule particle are considered simulation model. would be represented by mixture Based on CFD DPM technology, lubrication medium developed, includes solid film. And, structural parameters operation conditions characteristics investigated. results could suggestion for design structure working condition.