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Special Relativity’s “Newtonization” in Complex “Para-Space”: The Two Theories Equivalence Question
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作者 Jerzy K. Filus 《Journal of Applied Mathematics and Physics》 2024年第7期2421-2451,共31页
Complex model, say C3, of “para-space” as alternative to the real M4 Minkowski space-time for both relativistic and classical mechanics was shortly introduced as reference to our previous works on that subject. The ... Complex model, say C3, of “para-space” as alternative to the real M4 Minkowski space-time for both relativistic and classical mechanics was shortly introduced as reference to our previous works on that subject. The actual aim, however, is an additional analysis of the physical and para-physical phenomena’ behavior as we formally transport observable mechanical phenomena [motion] to non-real interior of the complex domain. As it turns out, such procedure, when properly set, corresponds to transition from relativistic to more classic (or, possibly, just classic) kind of the motion. This procedure, we call the “Newtonization of relativistic physical quantities and phenomena”, first of all, includes the mechanical motion’s characteristics in the C3. The algebraic structure of vector spaces was imposed and analyzed on both: the set of all relativistic velocities and on the set of the corresponding to them “Galilean” velocities. The key point of the analysis is realization that, as a matter of fact, the relativistic theory and the classical are equivalent at least as for the kinematics. This conclusion follows the fact that the two defined structures of topological vector spaces i.e., the structure imposed on sets of all relativistic velocities and the structure on set of all “Galilean” velocities, are both diffeomorphic in their topological parts and are isomorphic as the vector spaces. As for the relativistic theory, the two approaches: the hyperbolic (“classical” SR) with its four-vector formalism and Euclidean, where SR is modeled by the complex para-space C3, were analyzed and compared. 展开更多
关键词 special Relativity’s Hyperbolic Versus Circular Versions Galilean Kinematics Partial Equivalence of sR and Newton’s theories Algebra of Relativistic and the Corresponding Galilean Velocities
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On the Study of the Translator's Position in Traditional Translation Theories
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作者 张万防 郑惠婷 《海外英语》 2011年第8X期236-237,共2页
In traditional translation theories, the author and the translator, the original text and the translated text are in the binary oppositions. Both author-centeredness and text-centeredness are in authoritative position... In traditional translation theories, the author and the translator, the original text and the translated text are in the binary oppositions. Both author-centeredness and text-centeredness are in authoritative positions. Moreover, there are some incorrect viewpoints about the translator's position in the traditional translation theories. In this case, this paper will analyze the translator's position in the traditional translation theories comprehensively. 展开更多
关键词 traditional translation theories author-centeredness text-centeredness The Translator’s POsITION
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Comparative study of different theories on active earth pressure 被引量:1
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作者 S.P.Yap F.A.Salman S.M.Shirazi 《Journal of Central South University》 SCIE EI CAS 2012年第10期2933-2939,共7页
Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs. A number of analytical theories on active earth pressure were presented. Yet, there are limited studies on com... Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs. A number of analytical theories on active earth pressure were presented. Yet, there are limited studies on comparison between the theories. In this work, comparison between the theories with finite element analysis is done using the PLAXIS software. The comparative results show that in terms of distribution and magnitude of active earth pressure, RANKINE's theory possesses the highest match to the PLAXIS analysis. Parametric studies were also done to study the responses of active earth pressure distribution to varying parameters Increasing soil friction angle and wall friction causes decrease in active earth pressure. In contrast, active earth pressure increases with increasing soil unit weight and height of wall. RANK/NE's theory has the highest compatibility to finite element analysis among all theories, and utilization of this theory leads to proficient retaining wall design. 展开更多
关键词 active earth pressure retaining wall PLAXIs comparative study RANKINE's theory COULOMB's theory
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Reproduction and Mortality of Re-introduced Przewalski's Horse Equus przewalskii in Hustai National Park, Mongolia 被引量:1
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作者 Usukhjargal Dorj Bandi Namkhai 《Journal of Life Sciences》 2013年第6期623-629,共7页
The reproduction rate of Equus przewalskii in this study increased from year to year showing that the wild horses have already felt comfortable in the new environment and became acclimatized successfully. Of the mares... The reproduction rate of Equus przewalskii in this study increased from year to year showing that the wild horses have already felt comfortable in the new environment and became acclimatized successfully. Of the mares which were born in Hustai National Park and successfully reached reproductive age, 24.7% first gave birth at age 3 and 55.6% of them first gave birth at age 4. The most effective age range within the breeding population was 5 to 15, 25%-89% of them giving birth and an average during 2002-2011 of 72.9%. Of the Przewalski's horses which died, 65% were foals, 9.4% subadult male, 7.7% subadult female, 7.2% adult male and 10.6% were adult females. Causes of mortality differed by age and sex although wolf attacks accounted for the predominant number of deaths among foals and subadults. Stallions usually died of bad condition and injuries but parturition problems were common causes of death among mares. The mortality rate of foals (40% in 1993-2011) is a matter of great concern since foals born in Hustai National Park are the only gain component now after the active reintroduction period came to an end. A total of 109 foals were killed by wolves in 1993-2011 but 52% of them were younger than one month. 展开更多
关键词 Przewalski's horse reproduction MORTALITY sEAsONALITY wolf attack.
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Fung’s Theories on Vascular Mechanobiology
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作者 刘树谦 《医用生物力学》 EI CAS CSCD 北大核心 2018年第S1期27-30,共4页
Mechanobiology is the study of how stress and strain are generated by cells and how these mechanical factors regulate cell morphology and function.The vascular system is subject to tensile and compressive stress and s... Mechanobiology is the study of how stress and strain are generated by cells and how these mechanical factors regulate cell morphology and function.The vascular system is subject to tensile and compressive stress and strain in the blood vessel wal that are generated by blood pressure and play a pivotal role in regulating vascular cell activities including proliferation,differentiation,apoptosis,and migration.These cellular processes are essential to vascular development,performance,and pathogenic alterations.Dr.Y.C.Fung has made significant contributions to vascular mechanobiology—establishing the uniform stress theory,addressing the generation and significance of uniform stress and strain across the blood vessel wall,and proposing the stress-growth theory,addressing the role of mechanical stress in regulating cell proliferative ac-tivities(Fung 1984,Fung 1990).These theories have exerted a profound impact on the development of Biomechanics and Mechanobiology in the vascular as well as other systems. 展开更多
关键词 Fung’s theories on VAsCULAR MECHANOBIOLOGY
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Effects of Cow’s Milk on Reproduction in ICR Male Mice
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作者 YU-XIA MA NAOYUKI EBINE +2 位作者 KAZUO AOKI MASAHIRO KUSUNOKI AND JUNICHI MISUMI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2009年第2期161-163,共3页
Objective To study the effects of Cow's milk on the reproduction in male mice. Methods Twenty-four male mice were divided randomly into two groups: milk group (M) and control group (C). Each mouse was given 10 m... Objective To study the effects of Cow's milk on the reproduction in male mice. Methods Twenty-four male mice were divided randomly into two groups: milk group (M) and control group (C). Each mouse was given 10 mL milk per day from 4 to 16 weeks in the group M. At the age of 17 weeks, all the mice were sacrificed. Results Serum testosterone was decreased in the group M (P=0.037). No significant difference was found in weight of testes, seminal vesicle or adrenal gland of mice between the groups C and M. However, the weight of seminal vesicle decreased when expressed in g/100 g body weight in the group M. Epididymal sperm concentration, motility, morphology, and sperm head number were not affected by milk. Conclusion Cow's milk has adverse effects on the reproductive system in ICR male mice. Further studies are needed to clarify the specific effects of milk on reproductive health. 展开更多
关键词 Cow's milk Male mice reproductive health
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Analyzing whether China is a Welfare State Grounded on the Study of Esping-Andersen's Theories
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作者 田汶灵 《海外英语》 2018年第22期246-247,共2页
Indisputably,the desire for sense of security as a part of society brings about Citizens'aspiration for sound welfare.It's not only the wishes of citizens of capitalistic states but socialist countries.This pa... Indisputably,the desire for sense of security as a part of society brings about Citizens'aspiration for sound welfare.It's not only the wishes of citizens of capitalistic states but socialist countries.This paper focuses on analyzing whether China is a welfare state grounded on the study of Esping-Andersen’s theories.It consists of three dimensions,conceptual definitions published by Asa Briggs and Esping-Andersen is the primary one,then the basic three directions to modify the play of market(Asa Briggs)are stated as the criteria to measure a state,the third part is the principle Esping-Andersen proposed,and three kinds of welfare state based on the principle.To make the research more evident,examples will be utilized as follows. 展开更多
关键词 WELFARE China Esping-Andersen’s theories
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基于D-S证据理论的岩爆预测方法研究 被引量:1
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作者 高永涛 朱强 +1 位作者 吴顺川 王勇兵 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第2期244-251,共8页
为了有效预测岩爆,提出基于D-S证据理论的岩爆预测方法.首先,选取与岩爆发生相关的6个指标因素作为证据体,并通过模糊物元框架和正态型隶属度函数构建证据体的基本概率分配.然后,利用K均值将证据体分类,并提出簇内证据用传统方式融合而... 为了有效预测岩爆,提出基于D-S证据理论的岩爆预测方法.首先,选取与岩爆发生相关的6个指标因素作为证据体,并通过模糊物元框架和正态型隶属度函数构建证据体的基本概率分配.然后,利用K均值将证据体分类,并提出簇内证据用传统方式融合而簇间证据用权重方式融合的组合融合规则,以减轻高冲突证据融合的不利影响.最后,将模型应用在秦岭终南山公路隧道2号竖井工程,且与经验方法对比.为了分析预测过程的不确定性和估计岩爆发生概率,采用蒙特卡洛模拟进行抽样仿真,并通过Spearman秩相关系数衡量输入指标的全局敏感性.研究结果表明:输入指标在不同的岩爆案例的影响程度差异较大且方向不同;5个岩爆案例的发生概率在40.8%~70.1%之间.该模型表现出优异的预测分类性能,可为深埋地下工程岩爆预测提供参考. 展开更多
关键词 岩石力学 岩爆预测 D-s证据理论 模糊物元 K均值
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D-S证据理论在空中目标识别中的应用现状与展望
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作者 余付平 黄益恒 +2 位作者 沈堤 李靖宇 房瑞跃 《电光与控制》 CSCD 北大核心 2024年第4期75-86,共12页
D-S证据理论作为一种多源信息融合工具,在空中目标识别领域中得到了广泛应用。对D-S证据理论进行了概述;简要梳理了D-S证据理论在空中目标识别领域中的发展脉络,并提出应用中需要解决的三类关键问题;围绕上述问题,重点对该领域中的BPA... D-S证据理论作为一种多源信息融合工具,在空中目标识别领域中得到了广泛应用。对D-S证据理论进行了概述;简要梳理了D-S证据理论在空中目标识别领域中的发展脉络,并提出应用中需要解决的三类关键问题;围绕上述问题,重点对该领域中的BPA获取、证据冲突度量、证据融合的应用现状进行综述;最后,基于空域控制视角,对D-S证据理论在该领域中的应用进行了展望。研究可为空中目标识别领域的理论发展和工程应用提供参考。 展开更多
关键词 空中目标识别 D-s证据理论 BPA 证据冲突 证据融合
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D-S理论和Markov链组合的桥梁性能退化预测研究
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作者 杨国俊 田里 +2 位作者 唐光武 毛建博 杜永峰 《应用数学和力学》 CSCD 北大核心 2024年第4期416-428,共13页
为准确预测桥梁性能退化,考虑到数据随机性和微小扰动发生状态跳跃,提出了一种D-S(Dempster-Shafer)证据理论和Markov链组合的桥梁性能退化组合预测模型和性能退化率的概念.该模型基于指数平滑(exponential smoothing,ES)方法获得新的... 为准确预测桥梁性能退化,考虑到数据随机性和微小扰动发生状态跳跃,提出了一种D-S(Dempster-Shafer)证据理论和Markov链组合的桥梁性能退化组合预测模型和性能退化率的概念.该模型基于指数平滑(exponential smoothing,ES)方法获得新的预测数据序列,并利用Markov链和D-S理论不断进行优化,从而实现桥梁性能退化的组合预测.实际工程的应用结果表明:性能退化率可以直观地表征在梁性能退化的速度.其次,该模型的平均相对误差为1.54%,较于回归、灰色和模糊加权Markov链模型,精度分别提高了1.11%,0.88%和2.8%,而后验差比值为0.242,小于0.35;模型的标准差为9.021,相比其他模型分别减小了3.978,3.405和7.500,而变异系数为0.109,均小于其他模型,验证了组合预测模型在精度和稳定性方面的优越性,可为在役桥梁结构性能退化预测与维护提供理论基础. 展开更多
关键词 桥梁工程 性能退化预测 D-s证据理论 MARKOV链 组合预测模型 桥梁性能退化率
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基于D-S证据理论的农作物气候品质预测方法研究:以晚熟杂交柑橘春见为例
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作者 付世军 李梦 +6 位作者 杨晓兵 何震 袁佳阳 刘书慧 徐越 卢德全 张利平 《贵州农业科学》 CAS 2024年第5期122-132,共11页
【目的】基于多源气象数据构建果实品质(糖含量等级)预测模型,为科学评价果实气候品质及深入挖掘农产品气候资源提供科学依据。【方法】以晚熟柑橘春见果实为研究对象,利用多源数据融合技术、人工神经网络(BP神经网络、RBF神经网络和El... 【目的】基于多源气象数据构建果实品质(糖含量等级)预测模型,为科学评价果实气候品质及深入挖掘农产品气候资源提供科学依据。【方法】以晚熟柑橘春见果实为研究对象,利用多源数据融合技术、人工神经网络(BP神经网络、RBF神经网络和Elman神经网络)和D-S证据理论,包括气象数据质量控制、特征选取、特征级融合、决策级融合4个步骤,构建基于多源气象数据的果实品质(糖含量等级)预测模型。【结果】春见果实品质预测模型采用BP神经网络预测结果总体准确率为87.50%,平均绝对误差(MAE)为0.150,均方根误差(RMSE)为0.447;RBF神经网络预测结果总体准确率为85.00%,MAE为0.175,RMSE为0.474;Elman神经网络预测结果总体准确率为87.50%,MAE为0.150,RMSE为0.447;D-S证据理论决策融合总体预测准确率达95.20%,分别较BP神经网络、RBF神经网络和Elman神经网络提升7.7百分点、10.2百分点和7.7百分点,MAE和RMSE分别为0.040和0.214,均明显降低。【结论】D-S证据理论决策融合后的果实品质预测准确率相比单一神经网络预测更高、误差更小。 展开更多
关键词 晚熟柑橘 春见 气候品质 多源数据融合 BP神经网络 RBF神经网络 ELMAN神经网络 D-s证据理论
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基于加权D-S证据理论的旋翼故障诊断
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作者 高亚东 张传壮 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第1期66-75,共10页
旋翼作为直升机的升力面和操作面,其健康状态对直升机的安全至关重要。旋翼故障诊断技术仍是直升机健康与使用监测系统(Health and usage monitoring system, HUMS)领域的薄弱环节,开发旋翼故障诊断技术具有重要价值。基于信息融合技术... 旋翼作为直升机的升力面和操作面,其健康状态对直升机的安全至关重要。旋翼故障诊断技术仍是直升机健康与使用监测系统(Health and usage monitoring system, HUMS)领域的薄弱环节,开发旋翼故障诊断技术具有重要价值。基于信息融合技术,首先分析了旋翼故障的诊断机理,建立了旋翼故障模型,通过流固耦合仿真获取了不同故障下桨叶、轮毂和机身的故障特征信息,生成数据集进行网络训练和验证。然后,利用遗传算法反向传播(Genetic algorithm-backpropagation, GA-BP)优化神经网络诊断3种类型的直升机旋翼故障,即后缘调整片误调、变距拉杆误调和桨叶质量不平衡。3个逐级神经网络分别对旋翼故障类型、故障位置和故障程度进行了诊断识别。最后采用加权的Dempster-Shafer(D-S)证据理论对旋翼故障进行诊断和分析。结果证明基于改进D-S证据理论的旋翼故障诊断方法能够成功应用到旋翼故障诊断中,并具有良好的识别效果。 展开更多
关键词 旋翼系统 故障诊断 GA-BP神经网络 信息融合技术 D-s证据理论
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基于D-S证据理论改进AHP-熵权的流域洪涝灾害评估研究
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作者 苑希民 高瑞梅 +1 位作者 田福昌 侯玮 《水资源与水工程学报》 CSCD 北大核心 2024年第1期9-16,共8页
考虑致灾因子危险性、孕灾环境敏感性以及承灾体易损性,选取指标构建小清河流域洪涝灾害风险评估指标体系,提出一种基于D-S证据理论的改进AHP-熵权法计算指标权重,求取洪涝灾害风险指数,运用自然断点分级法确定洪涝灾害风险等级,分析小... 考虑致灾因子危险性、孕灾环境敏感性以及承灾体易损性,选取指标构建小清河流域洪涝灾害风险评估指标体系,提出一种基于D-S证据理论的改进AHP-熵权法计算指标权重,求取洪涝灾害风险指数,运用自然断点分级法确定洪涝灾害风险等级,分析小清河流域洪涝灾害风险空间分布情况。结果表明:小清河流域洪涝灾害风险总体上表现出南低北高的趋势,其中高风险区和较高风险区分别占流域面积的8.7%和14.3%,主要分布在小清河干流以及主要支流两岸。所得评估结果同“利奇马”台风发生期间实际洪灾风险分布情况一致,对比证明基于D-S证据理论的改进AHP-熵权法优于AHP和熵权法,可为小清河流域防洪减灾决策提供依据。 展开更多
关键词 D-s证据理论 AHP 熵权法 洪涝灾害评估 小清河流域
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达人主播直播带货对消费者购买意愿的双路径影响——基于SOR及ELM模型的分析
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作者 郑亚琴 陈慧娴 郑宇晨 《铜陵学院学报》 2024年第5期15-21,共7页
文章基于SOR模型和ELM模型,研究了达人主播直播带货营销对消费者购买意愿的影响机理。该研究发现,消费者购买意愿通过中心路径和边缘路径被影响,中心路径因素为信息质量和促销激励,而边缘路径因素为达人主播的专业性、知名度和社会临场... 文章基于SOR模型和ELM模型,研究了达人主播直播带货营销对消费者购买意愿的影响机理。该研究发现,消费者购买意愿通过中心路径和边缘路径被影响,中心路径因素为信息质量和促销激励,而边缘路径因素为达人主播的专业性、知名度和社会临场感。此外,消费者的感知信任和感知价值对其购买意愿具有显著正向影响,并在不同因素之间起中介作用。本研究结果提供了一个包括感知信任和感知价值双路径的中介影响模型框架,为未来研究该领域提供了新的思路和实证基础。 展开更多
关键词 直播带货 达人主播 sOR理论 ELM模型 购买意愿
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Support from Healthcare Professionals for Couples/Partners Undergoing Assisted Reproductive Technology in Japan: A Literature Review
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作者 Mikio Watanabe Naohiro Hohashi 《Open Journal of Nursing》 2023年第12期875-889,共15页
Background and Purpose: A growing number of couples/partners have been undergoing assisted reproductive technology (ART) in Japan. The purpose of this study was to clarify the support from healthcare professionals bas... Background and Purpose: A growing number of couples/partners have been undergoing assisted reproductive technology (ART) in Japan. The purpose of this study was to clarify the support from healthcare professionals based on the support vectors in the Family Care/Caring Theory proposed by Hohashi (2015) through a literature review. Methods: Using Ichushi-Web, we searched for original articles using the keywords “assisted reproductive technology”, “infertility”, “family”, “couple”, “nursing”, “care”, and “support”. Thirteen articles suitable for the purpose of this study were subjected to content analysis. Family support was encoded and grouped into subcategories and categories, and classified according to support vectors. Results: A total of 21 categories of support from healthcare professionals was extracted. Intervention for family internal environment included seven categories, such as “Nursing professionals stay close to females”. Intervention for family system unit included five categories, such as “Nursing professionals adjust couple/partner relationships”. Intervention for micro system only included “Nursing professionals provide opportunities for peer support to the couples/partners” and intervention for macro system only included “Nursing professionals encourage medical doctors to relate to females”. Intervention for family chrono environment included seven categories, such as “Healthcare professionals resolve female’s anxieties”. Conclusion: The support from healthcare professionals could be organized by the support vectors of Family Care/Caring Theory, but intervention for supra system (culture, religion, etc.) was lacking. Moreover, because most support was directed toward females or couples/partners, male-focused direct and/or indirect support are also needed. . 展开更多
关键词 Assisted reproductive Technology INFERTILITY Family support Family Care/Caring Theory Literature Review
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A New Page for Women's Reproductive Health in Integrated Traditional Chinese and Western Medicine
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作者 俞瑾 《Chinese Journal of Integrated Traditional and Western Medicine》 2003年第2期84-87,共4页
The integrated traditional Chinese and western medicine (ICWM) of obstetrics and gynecology (OBS/GYN) emerged eventually with more than 40 years’ hard struggle, and one of the most promising articles is the integrati... The integrated traditional Chinese and western medicine (ICWM) of obstetrics and gynecology (OBS/GYN) emerged eventually with more than 40 years’ hard struggle, and one of the most promising articles is the integration of the masterpieces of menstrual disorder and infertility in TCM and the virtual explosion of new knowledge and methods in 展开更多
关键词 in have A New Page for Women’s reproductive Health in Integrated Traditional Chinese and Western Medicine for that body of PCOs been is OBs TCM with FsH
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Youth’s Perspectives on a Sustainable Model for the Provision of Youth Friendly Sexual and Reproductive Health Services in Kenya: A Quantitative Approach
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作者 Mary W. Murigi Ramadimetja S. Mogale Miriam M. Moagi 《Journal of Biosciences and Medicines》 2020年第8期100-115,共16页
Nearly half of the world’s population comprise youths. However, addressing their Sexual and Reproductive Health (SRH) remains a challenge. Globally countries are mandated to continually provide Youth Friendly Sexual ... Nearly half of the world’s population comprise youths. However, addressing their Sexual and Reproductive Health (SRH) remains a challenge. Globally countries are mandated to continually provide Youth Friendly Sexual and Reproductive Health services (YFSRHs) to the youth. The objective of this study was to assess and describe youth’s perspectives on a sustainable model for the provision of YFSRHs in Kenya. Data was collected among 400 youths aged 18 - 24 years in Embu and Kirinyaga counties, Kenya. A structured questionnaire was utilized as the data collection tool. Collected data was analyzed using SAS statistical software version 9.4. Statistical threshold of P ≤ 0.05 was used. Overall the mean age of the study participants was ±standard deviation (SD) 21.2 ± 1.86 years. Majority of the participants’ perspective on the health care system sustainability was that the waiting time at the facility should be less than an hour, accessible geographically (less than a kilometre), affordable (≤20 Ksh.), and convenient working hours (weekday and weekends ratio 1:1). Advocacy was on health care provider’s attributes of politeness, welcoming, confidential and non-judgmental. The most preferred locations for the youth friendly centres by the participants were community and school based locations. Similarly, parental and community support was reported to highly contribute to sustained utilization and provision of the YFSRHs (P < 0.001). Unlike popular belief, 99.8% did not see the need for recreational facilities at the youth centres to ensure sustainability of the model. To ensure a sustainable model for the provision of YFSRHs, there is need for a multi-sectoral and stakeholder involvement that is;youth, health care system structure, health care service providers, parents and community. Further research is needed on parents and health care service provider’s perspectives on how to sustain the provision of YFSRH services. 展开更多
关键词 Youth’s sexual and reproductive Health Youth Friendly services sustainable Model
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Effect of Migration on Rural Women's FP and Reproductive Health
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《China Population Today》 2001年第Z2期7-11,共5页
关键词 Effect of Migration on Rural Women’s FP and reproductive Health THAN IUD FP
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基于D-S证据理论的配电网接地故障原因综合辨识模型
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作者 胡云鹏 都成刚 +4 位作者 齐军 郑日红 阿敏夫 张浩 梁永亮 《中国电力》 CSCD 北大核心 2024年第10期133-142,共10页
单相接地故障(single-phase-to-ground fault,SPGF)是配电网中最常见的故障,严重影响配电系统的可靠性和安全性,准确辨识SPGF可以提高配电网接地故障处理的精细化水平。首先,从故障波形中提取能有效反映不同接地故障原因的多域特征组成... 单相接地故障(single-phase-to-ground fault,SPGF)是配电网中最常见的故障,严重影响配电系统的可靠性和安全性,准确辨识SPGF可以提高配电网接地故障处理的精细化水平。首先,从故障波形中提取能有效反映不同接地故障原因的多域特征组成候选波形特征集,通过多元方差法分析波形特征与接地故障原因的相关性,筛选识别接地故障原因的有效特征;然后,分别设计基于极限学习机和支持向量机的故障原因辨识模型,利用Dempster-Shafer(D-S)证据融合理论对模型的识别结果进行融合,建立了接地故障原因综合辨识模型;最后,基于现场数据对所建立的综合辨识模型的有效性进行了验证,结果表明综合辨识模型优于任何单一辨识模型,验证了该模型的优势和可行性。 展开更多
关键词 接地故障原因 单相接地故障 极限学习机 支持向量机 D-s证据理论
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改进YOLOv7-tiny与D-S理论结合的实验室人员行为检测研究
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作者 杨永亮 曹敏 +4 位作者 徐凌桦 王霄 杨靖 王涛 冯平平 《现代电子技术》 北大核心 2024年第19期153-160,共8页
针对目前实验室场景缺少对人员行为检测的方法,且主流算法精度低、误检率高的问题,文中提出一种改进YOLOv7-tiny的人员行为检测算法,并通过多源信息融合,提高人员行为在实际实验室场景中的识别准确率。首先,在检测算法主干网络引入Ghost... 针对目前实验室场景缺少对人员行为检测的方法,且主流算法精度低、误检率高的问题,文中提出一种改进YOLOv7-tiny的人员行为检测算法,并通过多源信息融合,提高人员行为在实际实验室场景中的识别准确率。首先,在检测算法主干网络引入GhostNetV2轻量化网络,进一步降低模型计算量和复杂度;其次,在颈部网络嵌入改进后的CBAM_E注意力模块,加强目标重要特征的提取;再次,在预测端使用SIoU替换原有的损失函数,减少角度因素和边界框回归精度的影响。检测结果表明,相较于YOLOv7-tiny,文中算法精度提升10.08%,模型参数量和复杂度分别下降36.45%和46.76%。最后通过将检测数据与传感器采集数据运用D-S证据理论进行信息融合后发现,人员不规范行为检测的误检率得到有效降低。结果表明,该方法可实现对实验室人员不规范行为的有效检测。 展开更多
关键词 实验室场景 人员行为 YOLOv7-tiny 轻量化网络 注意力模块 损失函数 D-s证据理论 信息融合
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