Introduction: Birth spacing to prevent closely-spaced pregnancies, which are a source of maternal and neonatal morbidity and mortality, is not always respected by our women, as recommended by the World Health Organiza...Introduction: Birth spacing to prevent closely-spaced pregnancies, which are a source of maternal and neonatal morbidity and mortality, is not always respected by our women, as recommended by the World Health Organization (WHO). The objective was to study the factors associated with closely-spaced pregnancies among women followed at the Departmental Hospital Center du Zou et du Colline (DHC/Z-C) in 2022. Study Method: This was a descriptive, analytical cross-sectional study with prospective data collection from 20 May to 30 June 2022. Results: At the end of the study, 83 of the 117 women surveyed had close pregnancies, a frequency of 70.94%. They had an average age of 27.0 ± 6.3 years and were of Fon ethnicity and related in 91.57% of cases. The majority were married (96.60%). The factors significantly associated with these closely spaced pregnancies were age between 25 and 30 years, household occupation, age at first birth, age at marriage, women’s perception of contraceptive method (CM), women’s knowledge of the existence of a center providing family planning services and non-use of MC. Conclusion: Close pregnancies are still very common in the commune of Abomey. It is therefore important to increase the use of contraceptive methods in this part of the country.展开更多
为拓宽电压输出范围,并保持零电压开关ZVS(zero voltage switching)和零电流开关ZCS(zero current switching)的特征,提出了一种新型DHC-LT双向谐振型DC-DC变换器。首先,讨论了变换器在降压和升压工作时的工作模态和特性,利用辅助变压...为拓宽电压输出范围,并保持零电压开关ZVS(zero voltage switching)和零电流开关ZCS(zero current switching)的特征,提出了一种新型DHC-LT双向谐振型DC-DC变换器。首先,讨论了变换器在降压和升压工作时的工作模态和特性,利用辅助变压器提升电压增益,采用移相控制的方式降低变换器的输出电压。随后,在变压器上增加拾取绕组,并基于此提出一种新型的磁偏检测电路和数字调节方式。最终,搭建了一台2.5 kW样机,验证了以上理论分析,且最高效率可达97.4%。展开更多
文摘Introduction: Birth spacing to prevent closely-spaced pregnancies, which are a source of maternal and neonatal morbidity and mortality, is not always respected by our women, as recommended by the World Health Organization (WHO). The objective was to study the factors associated with closely-spaced pregnancies among women followed at the Departmental Hospital Center du Zou et du Colline (DHC/Z-C) in 2022. Study Method: This was a descriptive, analytical cross-sectional study with prospective data collection from 20 May to 30 June 2022. Results: At the end of the study, 83 of the 117 women surveyed had close pregnancies, a frequency of 70.94%. They had an average age of 27.0 ± 6.3 years and were of Fon ethnicity and related in 91.57% of cases. The majority were married (96.60%). The factors significantly associated with these closely spaced pregnancies were age between 25 and 30 years, household occupation, age at first birth, age at marriage, women’s perception of contraceptive method (CM), women’s knowledge of the existence of a center providing family planning services and non-use of MC. Conclusion: Close pregnancies are still very common in the commune of Abomey. It is therefore important to increase the use of contraceptive methods in this part of the country.
文摘为拓宽电压输出范围,并保持零电压开关ZVS(zero voltage switching)和零电流开关ZCS(zero current switching)的特征,提出了一种新型DHC-LT双向谐振型DC-DC变换器。首先,讨论了变换器在降压和升压工作时的工作模态和特性,利用辅助变压器提升电压增益,采用移相控制的方式降低变换器的输出电压。随后,在变压器上增加拾取绕组,并基于此提出一种新型的磁偏检测电路和数字调节方式。最终,搭建了一台2.5 kW样机,验证了以上理论分析,且最高效率可达97.4%。
