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In this paper, a wide-band, low-profile antenna is presented for a high-integration phased array system. The proposed antenna, implemented using a tightly coupled array, operates over roughly the X-K frequency band and is performant at 8 GHz–18.5 GHz. The antenna can scan to ± 60 degrees in both the E- and H-planes. Compared to previous tightly coupled antennas with smaller element spacing, the antenna in this paper reaches 9.4 mm, which corresponds to 0.58   λ of high frequency, suitable for engineering application conditions in production. The antenna can be soldered to BGA T/R chips in this space. Additionally, to facilitate flexible assembly for large arrays, the antenna is manufactured modularly using four elements and its parasitic radiation is analyzed. Then, a method for repressing parasitic radiation is presented. Finally, the antenna is fabricated and measured in a microwave chamber, exhibiting an excellent pattern and scanning radiation. The measured performance agrees with the full-wave finite array simulations. [ABSTRACT FROM AUTHOR]

This study investigated the effect of sustained loading on the cumulative damage of a newly developed smart cement-based self-healing composite material (SMA-ECC). SMA-ECC is composed of engineered cementitious composite (ECC) and shape memory alloy (SMA) fibers. A uniaxial compressive test with five predefined loading levels (0%, 30%, 40%, 50%, and 60% of compressive strength) was conducted on SMA-ECC hollow-cylindrical specimens and ECC control hollow-cylindrical specimens. The cumulative damage was mainly determined by changes in the total water absorption of different groups of specimens during three different periods (not loaded, at a predefined loading level, and after unloading). A normalized water content index was proposed to couple the effects of self-healing, sustained loading, and cumulative damage. The test results indicate that the cumulative water absorption of SMA-ECC was 35% lower than that of ECC, which may indicate less irreparable damage. In addition, the self-healing ability of SMA-ECC specimens under different compression load levels was evaluated through normalized water content analysis. SMA-ECC exhibited a 100% repair rate at load levels of 30% and 40%. At a higher load level of 60%, the repair rate of SMA-ECC was 76%. These results collectively emphasize the significant impermeability and self-healing performance of SMA-ECC after unloading. [ABSTRACT FROM AUTHOR]

Unbalanced and inadequate development has led to challenges such as resource shortage, ecological fragility, and economic backwardness in the water-receiving area of Henan Province, which has hindered the high-quality development of the region. This research aims to construct a high-quality development regulation model. The single-indicator quantification–multi-indicator synthesis–multicriteria integration (SMI-P) method was used to evaluate the level of regional development; using the method of embedded system dynamics, the regulation model was constructed and applied. The results show that (1) from 2011 to 2020, the degree of regional high-quality development showed an increasing trend, rising from a low level (0.34) to a medium level (0.57), an increase of one level, but the level of high-quality development still has a lot of room for improvement and faces great challenges; (2) the development of a resource–ecology–economy–social system was in a state of non-harmonious balance, and the proportion of contributions of each system was very different, but the system was developing towards a state of harmony and balance; (3) based on the constructed high-quality development regulation model, the key constraints affecting the high-quality development of the Yellow River water supply area in Henan Province are per capita water consumption, per capita energy consumption, carbon emissions per capita, GDP per capita, etc. The model constructed in this paper can improve the quality development level through the application of examples. The high-quality development degree of the study area was increased from 0.57 to 0.8. [ABSTRACT FROM AUTHOR]

Water resources are indispensable to human society. High-quality development (HQD) is a multi-faceted, demanding, and sustainable pattern. High-quality development level (HQDL) is an indicator of regional development. Its quantitative calculation is helpful to intuitively understand the current regional development situation, and helps departments make timely adjustments. Spatial equilibrium degree (SED) reflects the development balance among regions. Understanding spatial equilibrium can clarify regional development differences, promote the sharing of successful experiences, and then achieve common progress. Considering the current development and utilization situation of China's water resources, this study established an improved evaluation index system for HQDL, under water resources constraints. Then, we applied the proposed "single index quantification and multiple index synthesis and poly-criteria integration (SMI-P)" method to quantitatively evaluate the HQDL of China's 31 provincial-level administrative regions (PLARs), from 2010 to 2019. Finally, the calculation method of SED was employed to assess the SED of indicators and HQD in Mainland China. Results show that: (1) the HQDL of 31 PLARs showed a steady upward trend from 2010 to 2019. There were decrease tendencies from the coast to inland, and southeast to northwest in terms of spatial distribution, which shows that China's HQD has achieved remarkable results in the past 10 years, and the development of coastal areas is better; (2) The SED of HQD displayed a slow upward trend, and it has remained relatively stable after 2015, indicating that the spatial difference of HQD continued to shrink before 2015 and was relatively stable after that; (3) Water resource constraints played a significant role in well-developed areas, while the economic and social level was still the main constraint in medium and poor level areas. In addition, the spatiotemporal variation of HQDL, SED of HQD and indicators, and constraint effects of water resources on regional HQD, were fully discussed. Our findings not only provide new ideas for future research on HQD, but also possess great significance to China's HQD in the new era. [ABSTRACT FROM AUTHOR]

The conflict of the human-water relationships (HWR) has further increased the water-related risks, such as water environment deterioration, water shortages, and even regional violent conflicts for obtaining usable water resources. Knowing how to evaluate and regulate the discordant HWR to form a balanced growth between sustainable socio-economy and water resources protection has become a critical issue in water resources management. The harmony theory method, which provides a new perspective for solving the conflict between humans and water, has been widely used in current studies. However, this method focuses less on the quantitative study of the balance status of HWR. This study proposes a harmony theory-based HWR evaluation method that contains a systematic process of harmony assessment, indicator identification, harmony balance constraints, and harmony regulation for assessing and regulating the discordant HWR. The Henan Province of China, which has a complicated HWR, was selected as a case study to apply and verify the approach proposed in this study. The results indicated that (1) Henan Province showed a poor harmony status. The human–water harmony degree of 18 distinctions in the province varied from 0.41 to 0.76, showing an increasing trend from 2006 to 2018, indicating that the HWR was gradually improving in recent years. (2) The human–water harmony degree showed that HWR in the southwest part of Henan Province, with less human activities, was better than that in its northeast part, which had faster social development. Sanmenxia City, located in the west part of the province, had the highest human–water harmony degree because of the recent water control projects implemented in the city, indicating that human production measures could effectively help improve HWR. (3) At present, Henan Province has serious discordant indicators in these three aspects (water system health, humanistic system development, and human-water system coordination), which proves that it is still facing pressure from both socio-economy sustainable development and water resources protection. Our results provide insight into water resources management in Henan Province and other similar regions. [ABSTRACT FROM AUTHOR]