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A study was conducted to analyze a novel design theory using a phase inverter for the systematic size reduction and band broadening of a uniplanar hybrid ring coupler. The effective bandwidth of a new reverse-phase hybrid ring coupler can be increased by 28% supporting a return loss of 20 dB. A category of uniplanar phase inverters was then examined. Results indicated that the design supports freedom and tradeoff associated with designing broadband/narrow-band and size-reduced couplers.

An enhanced spectral domain approach (SDA) is developed for analysis of complex quasi-planar transmission lines. The method is based on a combination of spectral domain formulation and power conservation theorem. The relationship between electric and magnetic fields is established inside dielectric layers by using the conventional SDA while characteristic equation related to interface conditions is derived through the power conservation theorem. Maintaining the inherent advantages of the SDA, this technique is able to easily handle more complex quasi-planar structures. Generalized power formulation is also presented to calculate characteristic impedance. Convergence behavior is discussed considering the nature of power conservation. Various finlines with finite thickness of conductors are analyzed to demonstrate its applications.

Propagation characteristics of fundamental and higher-order modes are determined in coupled slotlines with three suspended mounting schemes (pedestal, groove, inverse pedestal) for wideband applications of microwave and millimeter-wave integrated circuits. The analysis is based on a novel enhanced spectral domain approach (ESDA) that combines essentially the conventional spectral domain technique with the power conservation theorem. Numerical results, considering also the influence of finite conductor thickness, are presented for propagation constants and characteristic impedance of the fundamental modes. Effects of different suspended mounting schemes on cutoff frequencies of first higher-order even and odd modes are discussed in detail. Field profiles of the fundamental modes in coupled slotlines with and without pedestals are shown. The inherent mechanism of mode transition is explained with respect to different pedestal sizes, indicating that the monomode bandwidth can be extended by appropriately choosing the dimension of pedestal in coupled slotlines.

In this paper, the kinematic analysis and numerical calculation are used to discuss the effect of the kinematic parameters on the final polishing result of typical rotary chemical-mechanical polishing (CMP) equipment. The relative velocity distribution and the sliding distance distribution are calculated based on the kinematic analysis. Especially, the coupling relationships between the kinematic parameters are investigated and discussed. And two parameters of the sliding distance nonuniformity (SDNU) and the sliding distance nonuniformity within concentric circles (SDNU\-cc) are proposed and calculated to evaluate the global uniformity of the sliding distance and to reveal the coupling relationships between the kinematic parameters. The results suggest that the relative velocity distribution and the sliding distance distribution are significantly affected by the coupling effects of the basic motions of CMP system; the SDNU is mainly affected by parameter \alpha, which represents the coupling relationship between the rotary motions of the wafer carrier and the polishing platen; the SDNU\-cc is mainly affected by parameter kT{0}^{\prime}(\alpha kT0), which represents the coupling relationship between the reciprocating motion and the rotary motion of the wafer carrier; \alpha\approx 1 and \alpha kT0>2 are proper for better polishing uniformity in real CMP process. [ABSTRACT FROM PUBLISHER]

This paper focuses on the study of micro-galvanic corrosion of the Cu/Ru couple in KIO 4 solution. Practical nobility across the Cu/Ru interface was evaluated by Volta potential mapping, and the morphological changes were monitored by in-situ atomic force microscopy measurements during exposure in a KIO 4 solution. Chemical composition of precipitated corrosion product was analyzed by Confocal Raman spectroscopy immediately after the exposure. The results show that Cu is the anode of the Cu/Ru couple, and accelerated dissolution of Cu preferentially occurs near the Cu/Ru interface. However, subsequent formation of insoluble Cu(IO 3 ) 2 ·nH 2 O leads to precipitation, which impedes further Cu corrosion. [ABSTRACT FROM AUTHOR]

Background: We aimed to investigate the prevalence of erectile dysfunction (ED) in patients with lower urinary tract symptoms (LUTS) and to explore the correlation of ED with LUTS and its clinical features., Methods: Overall, 400 outpatients and inpatients with LUTS diagnosed in Zhengzhou Central Hospital, Zhengzhou University, Zhengzhou, Henan Province, China from June 2015 to June 2017 were collected. LUTS degree was assessed by the International Prostate Symptom Score (IPSS), and ED degree was assessed by the International Index of Erectile Function (IIEF-5). The correlation of ED with LUTS degree, age, blood lipids, homocysteine (Hcy) and other factors was analyzed., Results: The prevalence of ED in patients with LUTS was 82.25%. With the increase in age, the prevalence of ED was significantly elevated, and ED degree gradually became higher ( P <0.01). The higher the degree of LUTS was, the higher the prevalence of ED would be. The degree of ED was highly correlated with the combination with hypertension, diabetes mellitus and coronary heart disease ( P <0.05). The prevalence of ED was positively correlated with LUTS degree and the levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and Hcy ( P <0.05 or P <0.01)., Conclusion: ED prevalence of patients with LUTS is high, and ED is significantly related to LUTS degree, age and the levels of TC, LDL-C and Hcy in patients with LUTS., Competing Interests: Conflicts of Interest The authors have no conflicts of interest to declare.