759 research outputs found
Impacts of different demographic policies adopted by the government on the Chinese population dynamics
This dissertation focuses on three demographic policies that Chinese government adopted after Eonomic reform in 1978: the one-child policy, the two-child policy, and the migration policy. In the first chapter, I employ regional and provincial level data to re-estimate the effect of the one-child policy on Chinese fertility applying a difference-in-differences (DD) methodology. I introduce geographic and other individual factors to show how the one-child policy distorted fertility rates and sex ratios in China after its implementation. For the second chapter, I also employing a DD approach, I focus on rural-to-urban migration and estimate the effect of the 1992 migration policy on the rural householdsâ migration decision. In the final chapter, I study in an OLG model how the two-child policy in China will change the current Pay-As-you-Go (PAYG) pension system in the future, and simulate different scenarios to evaluate the pension programme
Mantle Transition Zone Structure Beneath Northeast Asia From 2âD Triplicated Waveform Modeling: Implication for a Segmented Stagnant Slab
The structure of the mantle transition zone (MTZ) in subduction zones is essential for understanding subduction dynamics in the deep mantle and its surface responses. We constructed the P (V_p) and SH velocity (V_s) structure images of the MTZ beneath Northeast Asia based on twoâdimensional (2âD) triplicated waveform modeling. In the upper MTZ, a normal V_p but 2.5% low V_s layer compared with IASP91 are required by the triplication data. In the lower MTZ, our results show a relatively higherâvelocity layer (+2% V_p and â0.5% V_s compared to IASP91) with a thickness of ~140 km and length of ~1,200 km atop the 660âkm discontinuity. Taking this anomaly as the stagnant slab and considering the plate convergence rate of 7â10 cm/year in the western Pacific region during the late Cenozoic, we deduced that the stagnant slab has a subduction age of less than 30 Ma. This suggests that the observed stagnancy of the slab in the MTZ beneath Northeast Asia may have occurred no earlier than the Early Oligocene. From the constraints derived individually on V_p and V_s structures, high V_p/V_s ratios are obtained for the entire MTZ beneath Northeast Asia, which may imply a waterârich and/or carbonated environment. Within the overall higherâvelocity stagnant slab, a lowâvelocity anomaly was further detected, with a width of ~150 km, V_p and V_s reductions of 1% and 3% relative to IASP91. Such a gap may have provided a passage for hot deep mantle materials to penetrate through the thick slab and feed the Changbaishan volcano
Cost efficiency in China: An empirical analysis of commercial banks during 2013-2018
Abstract
In this paper, the cost efficiency of commercial banks is evaluated by SFA, a frontier method with random parameters. Among them, there are 147 commercial banks in the study, which mainly analyzed the situation from 2013 to 2018. According to the results of the analysis, it can be found that the average cost efficiency is 95.33%, which is relatively stable, but it would be different due to different years. In addition, the growth of GDP, inflation and the size of banks have no significant impact on the performance of banks. In the six years from 2013 to 2018, the joint-stock commercial banks (JSCBs) are generally more cost-effective than the large state-owned commercial banks (SOCBs)
Herbal Medicine Cordyceps sinensis
Moderate-to-severe asthma has a substantial impact on the health-related quality of life (HR-QOL) of the patients. Cordyceps sinensis is a traditional Chinese medicine that is evaluated clinically for the treatment of many diseases, such as chronic allograft nephropathy, diabetic kidney disease, and lung fibrosis. In order to investigate the effects of Cordyceps sinensis on patients with moderate-to-severe persistent asthma, 120 subjects were randomized to receive Corbin capsule containing Cordyceps sinensis for 3 months (treatment group, n=60), whereas the control group (n=60) did not receive treatment with Corbin capsule. Inhaled corticosteroid and as-needed β-agonists were used in the treatment of both groups. HR-QOL was measured with the Juniperâs Asthma Quality of Life Questionnaire (AQLQ). The incidence of asthma exacerbation, pulmonary function testing, and serum measurements of inflammatory mediators were also evaluated. The results showed that the treatment group indicated a significant increase in AQLQ scores and lung function compared with the control group. The expression levels of the inflammation markers IgE, ICAM-1, IL-4, and MMP-9 in the serum were decreased and IgG increased in the treatment group compared with the control group. Therefore, the conclusion was reached that a formulation of Cordyceps sinensis improved the HR-QOL, asthma symptoms, lung function, and inflammatory profile of the patients with moderate-to-severe asthma. This trial is registered with ChiCTR-IPC-16008730
Exploring the core knowledge of business intelligence
With the rapid development of data analysis, there is few research on the core knowledge of business intelligence system (BIS). In order to fill this research gap, this paper collected the 1003 articles and 31345 references from the Web of Science database, and then applied co-citation analysis and factor analysis, to analyze their core knowledge. We identified 52 highly cited articles and obtained 9 core knowledge categories in the field of BI: BI success, IT acceptance and measurement, big data analysis,dataanalysis anddecision making,business strategy, BIS,consumer behavior, knowledge management, business adoption. Research shows that BISs are still in the growing trend and core knowledge helps researchers and managers better understand the core concepts and relevance of BI, so as to quickly discover possible research directionsinthisresearchfieldandusefulapplicationsintheenterprise
Asymmetric impacts of technology innovation and environmental quality on tourism development in emerging economies
Tourism development contributes to higher economic output and
is highly integrated with environmental quality and associated
technologies. Although many studies explore the impact of tourism on carbon emissions; however, little is known regarding the
effects of environmental pollution and technology innovation on
tourism growth. Therefore, this study examines the impact of
technology innovation and environmental pollution on inbound
tourism in emerging economies. In doing so, we employ a
recently developed panel quantiles regression and found that
technology innovation and economic growth stimulate inbound
tourism while increasing emissions limit tourist arrivals. These
effects are not equally observed across all quantiles. Particularly,
the impact of technology innovation is highest at higher quantiles, while the impact of the emissions is highest at lower quantiles. These results suggest that inbound tourism is asymmetrically
affected by technology innovation and environmental quality of
host destinations. Hence, emerging economies should encourage
sustainable tourism by integrating green technologies and minimizing ecological hazards
Observations of Field Current and Field Winding Temperature in Electrically Excited Synchronous Machines with Brushless Excitation
Electrically excited synchronous machines have become an alternative in electrification of transportations and renewable power generations. To reduce the extra effort in the maintenance of sliprings and brushes for field excitation, brushless excitation has been developed. However, when brushless excitation is adopted, the field winding becomes physically inaccessible when the machine is rotating. To solve this problem, an algorithm is proposed in this study to observe the field current and field winding temperature of an EESM with brushless excitation. The stator currents are measured and then used to correct the machine state predictor. The correction of the state prediction is interpreted to adjust the field winding resistance and temperature value. The algorithm is evaluated in simulations. The estimations of field current and field winding temperature track the measurements successfully
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