Search

Maximum point power tracking (MPPT) technology is widely used to improve photovoltaic (PV) output power, and the traditional MPPT control methods are being used more and more widely. However, the PV system controlled by MPPT cannot be directly applied to the direct-current (DC) microgrid, and the output voltage is not stable, resulting in more than the DC bus rated voltage. Based on this problem, some researchers have proposed the control method with DC bus. At present, there are few researches on this control method in the world, the research status and process of this aspect are not discussed in detail. This paper analyzes and summarizes the PV system with DC bus of MPPT control method based on referring to the existing relevant literature, hoping to provide some help for the subsequent research and experiments of relevant researchers.

Objectives: Analyzing the lower limb coronal morphological parameters in populations without knee osteoarthritis (KOA) holds significant value in predicting, diagnosing, and formulating surgical strategies for KOA. This study aimed to comprehensively analyze the variability in these parameters among Chinese non‐KOA populations, employing a substantial sample size. Methods: A cross‐sectional retrospective analysis was performed on the Chinese non‐KOA populations (n = 407; 49.9% females). The study employed an in‐house developed artificial intelligence software to meticulously assess the coronal morphological parameters of all 814 lower limbs. The parameters evaluated included the hip‐knee‐ankle angle (HKAA), weight‐bearing line ratio (WBLR), joint line convergence angle (JLCA), mechanical lateral‐proximal‐femoral angle (mLPFA), mechanical lateral‐distal‐femoral angle (mLDFA), mechanical medial‐proximal‐tibial angle (mMPTA), and mechanical lateral‐distal‐tibial angle (mLDTA). Differences in these parameters were compared between left and right limbs, different genders, and different age groups (with 50 years as the cut‐off point). Results: HKAA and JLCA exhibited left–right differences (left vs. right: 178.2° ± 3.0° vs. 178.6° ± 2.9° for HKAA, p = 0.001; and 1.8° ± 1.5° vs. 1.4° ± 1.6° for JLCA, p < 0.001); except for the mLPFA, all other parameters show gender‐related differences (male vs. female: 177.9° ± 2.8° vs. 179.0° ± 3.0° for HKAA, p < 0.001; 1.5° ± 1.5° vs. 1.8° ± 1.7° for JLCA, p = 0.003; 87.1° ± 2.1° vs. 88.1° ± 2.1° for mMPTA, p < 0.001; 90.2° ± 4.0° vs. 91.1° ± 3.2° for mLDTA, p < 0.001; 38.7% ± 12.9% vs. 43.6% ± 14.1% for WBLR, p < 0.001; and 87.7° ± 2.3° vs. 87.4° ± 2.7° for mLDTA, p = 0.045); mLPFA increase with age (younger vs. older: 90.1° ± 7.2° vs. 93.4° ± 4.9° for mLPFA, p < 0.001), while no statistical difference exists for other parameters. Conclusions: There were differences in lower limb coronal morphological parameters among Chinese non‐KOA populations between left and right sides, different genders, and age. [ABSTRACT FROM AUTHOR]

During Yan'an period, the Chinese Communist Party established its own political power at Shanganning border area and each anti-Japanese base area, creatively solved a series of vital problem in new-democratic revolution and social development. Based on the development of democracy and social civilization, it continuously impelled the realization of education fair which acted as the extension and embodiment of value of social fair in the domain of democratic education, and realized the theory innovation and a series of reform practice of education in the aspects of mass line, equal right and equal opportunity. The accumulated plentiful and precious experience made the solid foundation for the national, scientific and popular culture education system of new China. [ABSTRACT FROM AUTHOR]