historical changes
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2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Xiaomei Sun ◽  
Haiou Zhang ◽  
Jian Wang ◽  
Chendi Shi ◽  
Dongwen Hua ◽  
...  

AbstractReliable and accurate streamflow forecasting plays a vital role in the optimal management of water resources. To improve the stability and accuracy of streamflow forecasting, a hybrid decomposition-ensemble model named VMD-LSTM-GBRT, which is sensitive to sampling, noise and long historical changes of streamflow, was established. The variational mode decomposition (VMD) algorithm was first applied to extract features, which were then learned by several long short-term memory (LSTM) networks. Simultaneously, an ensemble tree, a gradient boosting tree for regression (GBRT), was trained to model the relationships between the extracted features and the original streamflow. The outputs of these LSTMs were finally reconstructed by the GBRT model to obtain the forecasting streamflow results. A historical daily streamflow series (from 1/1/1997 to 31/12/2014) for Yangxian station, Han River, China, was investigated by the proposed model. VMD-LSTM-GBRT was compared with respect to three aspects: (1) feature extraction algorithm; ensemble empirical mode decomposition (EEMD) was used. (2) Feature learning techniques; deep neural networks (DNNs) and support vector machines for regression (SVRs) were exploited. (3) Ensemble strategy; the summation strategy was used. The results indicate that the VMD-LSTM-GBRT model overwhelms all other peer models in terms of the root mean square error (RMSE = 36.3692), determination coefficient (R2 = 0.9890), mean absolute error (MAE = 9.5246) and peak percentage threshold statistics (PPTS(5) = 0.0391%). The addressed approach based on the memory of long historical changes with deep feature representations had good stability and high prediction precision.


2022 ◽  
Author(s):  
Jingyun Guan ◽  
Junqiang Yao ◽  
Moyan Li ◽  
Dong Li ◽  
Jianghua Zheng

2021 ◽  
Vol 2 (6) ◽  
Author(s):  
Hanyu Zhao

This article is based on the history of British railway reform, combined with related theories and policies, and explored what kind of regulatory policies should be adopted in what kind of economic environment.


2021 ◽  
Vol 4 ◽  
Author(s):  
Yuji Ogihara

Currently, a social security number (SSN) is held by almost every legal resident of the United States and works as an important numbering system. However, this was not the case in the early years of the Social Security program and historical changes in SSN holder rates had not been examined sufficiently. It is important to understand the changes in health policies and situations. Thus, the present article examined historical changes in the rates of SSN holders in the United States between 1909 and 2019. Analyses demonstrated that the rates clearly increased. Specifically, in Phase 1 (1909-1919), the rates were low in the early period, but they increased markedly. In Phase 2 (1919-1952), the rates continued to increase gradually. In Phase 3 (1952-2019), the rates were almost 100% and reached saturation. This basic information leads to a better understanding of the health policies and situations, contributing to medical and social science research.


2021 ◽  
pp. 1-28
Author(s):  
Dan Deutsch

In this article I examine the impact on Felix Mendelssohn's music, as reflected in his Lieder ohne Worte (Songs without Words), of his affiliation with a German-Jewish subculture. To better understand the interrelationship between musical formations and sociocultural realities, I associate the real and imaginary tensions between the German, the Jewish, and the German-Jewish with stylistic ambiguities in Mendelssohn's piano songs, which often destabilize the lyrical simplicity projected by the lieder framework through formal complexities that exceed the narrow scope of the piano miniature. I establish the connections between Mendelssohn's music and sociocultural disposition by identifying a correlation between his so-called stylistic ‘conservatism’ and the anachronistic devotion of German Jewry to the universal ideals of the Enlightenment during the rise of German nationalism. Against this background, I primarily reveal the generic heterogeneity of the Lieder ohne Worte, which feature ‘progressive’ stylistic frameworks associated with the lied traditions yet concurrently point toward the formal ideals of eighteenth-century classicism. And following this, I position the stylistic duality of Mendelssohn's piano songs within a broader context through Heinrich Heine's essay The Romantic School, which sheds crucial light on the negotiation of Jewishness within German culture as it is reflected in aesthetic movements, historical changes, and political climates.


2021 ◽  
Author(s):  
Michael Colvin

Abstract Background - Demand in children’s social care remains at historically high levels across the UK. The number of children in local authority care in Scotland increased every year between 1998 and 2013. This study explores a possible trans-generational influence of historical changes in family structure at birth. Method - Children who were accommodated by a typical Scottish local authority from 2000 to 2013 were identified. The parental marital status on birth registrations of the children and their parents was compared to all Scottish registrations in national birth cohorts and relative risk (RR) was calculated for different birth circumstances. Results - The children who entered care were more likely to have been born to unmarried parents than their peers (RR 7.8, CI 6.3-9.6). Their mothers (RR 3.2, CI 2.7-3.9) and fathers (RR 1.5, CI 1.1-2) were also more likely than their peers to have been born to unmarried parents. The accumulated risk of young children entering care if their parents and maternal grandparents had been unmarried on birth registrations was very large (RR 23.3, CI 12.5-43.5). Conclusion - Parental marriage is protective against entering local authority care for children in Scotland. Historical changes in family structure at birth may influence demand in children’s services.


2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. 287-288
Author(s):  
Johanna Drewelies ◽  
Sandra Duezel ◽  
Margie Lachman ◽  
Jacqui Smith ◽  
Nilam Ram ◽  
...  

Abstract To examine historical changes in views on aging, we compared matched cohorts of older adults within two independent studies that assessed differences across a two-decade interval, the Berlin Aging Studies (BASE, 1990/93 vs. 2017/18, each n = 256, Mage = 77) and the Midlife in the United States Study (MIDUS, 1995/96 vs. 2013/14, each n = 848, Mage = 67). Consistent across four different dimensions of individuals’ subjective views on aging (age felt, age appeared, desired age, attitudes towards own aging) in the Berlin Aging Studies and corroborated with subjective age felt in the MIDUS, there was no evidence whatsoever that older adults of today have more favorable views on how they age than older adults did two decades ago. We discuss reasons for our findings, including the possibility that individual age views may have become increasingly decoupled from societal age views.


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