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Nowadays, the emerging digital technologies and digitalization trend in safety‐critical industrial process systems are bringing great opportunities for system performance improvements. However, new big challenges are also encountered in the reliability and safety evaluation of large complex industrial process systems due to its multi‐state, multi‐phase dynamic interactions, resilience on software and inter‐dependencies among digital components. The objectives of this study are i) to present an introductory overview of a hybrid computing framework as a supplementary to conventional fault tree analysis toolkit for risk‐oriented reliability analysis in dynamic probabilistic safety assessment context; ii) to illustrate how to combine the three methods of DDET, Markov/CCMT, and GO‐FLOW for integrated risk solutions by a case study of small‐break LOCA in nuclear power plants. Within the hybrid computing framework, the DDET model is implemented based on graph‐based search and sequence diagram refactoring by linking with Markov/CCMT and GO‐FLOW solver for branch probability estimation. The dynamic event tree model is adopted to represent the accident sequence of small‐break LOCA, where the heading events of system failure of digital RPS and phased‐mission ECCS in realization of safety‐critical functions of reactivity control and emergency core cooling are respectively modeled and analyzed by Markov chain and GO‐FLOW method. The demonstration results show that the failure analysis of complex dynamic process interactions together with time‐dependent mission reliability analysis of safety systems involved in accident prevention and mitigation can be easily implemented with accurate modeling and fast evaluation within the hybrid integration platform. The core algorithms and principles implemented for dynamic risk scenarios development by DDET, modeling, and analysis of dynamic process interactions by Markov/CCMT, time‐dependent and multi‐phase mission reliability analysis by GO‐FLOW as well as their integration to provide comprehensive solutions for the application of dynamic reliability in risk assessment are also discussed as open problems for future research. [ABSTRACT FROM AUTHOR]

The effect of growth pressure on the properties of β-Ga2 O3 thin films epitaxial on c-plane sapphire substrate with 6° oblique cut angle by plasma-assisted molecular beam epitaxy were systematically studied. All of the epitaxial films present (201) orientated single-crystalline structure with smooth surface morphology. In addition, the crystalline quality and growth rate increase gradually with the increase of the growth pressure, as demonstrated by X-ray diffraction and scanning electron microscopy characterizations. According to the X-ray photoelectron spectroscopy measurement results, the percentage of oxygen vacancy and Ga3+ oxidation states decrease and increase, respectively, with increasing growth pressure, resulting in the increment of atomic ratio of O to Ga. Moreover, through the calculation of Tauc formula and Urbach tail model, the results show that the optical band gap of the films increase from 4.94 eV to 5.00 eV, while Urbach energy decreases from 0.47 eV to 0.32 eV. These results suggest that the crystal quality and optical property of β-Ga2O3 were improved by increasing the growth pressure. [ABSTRACT FROM AUTHOR]

Construction materials are considerable forces of global environmental impacts, but their dynamics vis‐à‐vis urban development are poorly documented, in part because their long lifespans require elusive and sometimes nonexistent decade‐long high‐resolution data. This study analyzes the construction material flow and stock trends that shaped and were shaped by the development, decline, and renewal of the Tiexi district of Shenyang, a microcosm of China's urban transformations since the early 20th century. Chronicling building‐by‐building the material flows and stock accumulations involved in the buildup of this area, we shed light on the physical resource context of its socioeconomic history. We find that 42 million tonnes of construction materials were needed to develop the Tiexi district from 1910 to 2018, and 18 million tonnes of material outflows were generated by end‐of‐life building demolition. However, over 55% of inflows and 93% of outflows occurred since 2002 during a complete redevelopment of the district. Only small portions of end‐of‐life materials could have been reused or recycled because of temporal and typological mismatches of supply and demand and technical limitations. Our analysis reveals a dramatic decrease in median building lifetimes to as low as 6 years in the early 21st century. These findings contribute to the discussion of long‐term environmental efficiency and sustainability of societal development through construction and reflect on the challenges of urban renewal processes not only in China but also in other developing and developed countries that lost (or may lose) their traditional economic base and restructure their urban forms. This article met the requirements for a Silver/Silver JIE data openness badge described at http://jie.click/badges. [ABSTRACT FROM AUTHOR]

A miniaturized substrate integrated waveguide (SIW) end‐fire antenna with improved E‐plane radiation pattern for X and Ku bands is proposed in this letter. The width of the antenna is only 15 mm, which is about 0.7λ0 at the center frequency, and the height of the antenna is 3.5 mm, which is only 0.17λ0 at the center frequency. The two stepped metalized ridges are used for impedance matching, which can achieve a wide bandwidth from 10.2 GHz to 19 GHz. The four small metal strips which are placed at the front of the antenna and the other FR4 substrate are used to improve the stable E‐plane radiation direction of the antenna. The measured results and the simulated results have good agreement. [ABSTRACT FROM AUTHOR]

In this letter, a new wide stopband and high gain Quasi‐Yagi filtering antenna is proposed. At the beginning of feeder line in the improved Balun filtering antenna, it is integrated with the stripline low‐pass filter that contributes to wide out‐of‐band suppression. The proposed filtering antenna works from 2.25 GHz to 2.55 GHz, with a maximum gain of 8dBi at 2.5 GHz. Moreover, it possesses a faster roll‐off rate from 2.55 GHz(8 dB) to 2.8 GHz (−20 dB) and a better rejection up to 12 GHz(5 times of central frequency) outside the working band. [ABSTRACT FROM AUTHOR]

A high‐selectivity dual‐polarization filtering antenna with metamaterial is presented in this letter. The multilayer coupled radiation structure of the antenna determines a filtering function. With the metamaterial layer designed above the antenna, a sharp roll‐off rate at high pass band edge and a better out‐of‐band rejection occurs, thus a better high selective filtering characteristic can be achieved. Simulating and measuring the antenna, the impedance bandwidth (VSWR <2) of the antenna is from 3.25 GHz to 3.85 GHz; meanwhile, the maximum gain can reach 9dBi. The gain of antenna can quickly decrease 43dBi at the high pass band edge from 3.85 GHz to 4.05 GHz and the antenna has an out‐of‐band rejection level of 27dBi from 4.05 GHz to 5 GHz. The tested results verify our designs and the antenna could be a good candidate for the 5G anti‐interference wireless terminal communication system. [ABSTRACT FROM AUTHOR]