2,063 research outputs found
PM2.5-Related Health Economic Benefits Evaluation Based on Air Improvement Action Plan in Wuhan City, Middle China
On the basis of PM2.5 data of the national air quality monitoring sites, local population data, and baseline all-cause mortality rate, PM2.5-related health economic benefits of the Air Improvement Action Plan implemented in Wuhan in 2013–2017 were investigated using health-impact and valuation functions. Annual avoided premature deaths driven by the average concentration of PM2.5 decrease were evaluated, and the economic benefits were computed by using the value of statistical life (VSL) method. Results showed that the number of avoided premature deaths in Wuhan are 21,384 (95% confidence interval (CI): 15,004 to 27,255) during 2013–2017, due to the implementation of the Air Improvement Action Plan. According to the VSL method, the obtained economic benefits of Huangpi, Wuchang, Hongshan, Xinzhou, Jiang’an, Hanyang, Jiangxia, Qiaokou, Jianghan, Qingshan, Caidian, Dongxihu, and Hannan District were 8.55, 8.19, 8.04, 7.39, 5.78, 4.84, 4.37, 4.04, 3.90, 3.30, 2.87, 2.42, and 0.66 billion RMB (1 RMB = 0.1417 USD On 14 October 2019), respectively. These economic benefits added up to 64.35 billion RMB (95% CI: 45.15 to 82.02 billion RMB), accounting for 4.80% (95% CI: 3.37% to 6.12%) of the total GDP of Wuhan in 2017. Therefore, in the process of formulating a regional air quality improvement scheme, apart from establishing hierarchical emission-reduction standards and policies, policy makers should give integrated consideration to the relationship between regional economic development, environmental protection and residents’ health benefits. Furthermore, for improving air quality, air quality compensation mechanisms can be established on the basis of the status quo and trends of air quality, population distribution, and economic development factors
Adaptive Finite Element Approximations for Kohn-Sham Models
The Kohn-Sham equation is a powerful, widely used approach for computation of
ground state electronic energies and densities in chemistry, materials science,
biology, and nanosciences. In this paper, we study the adaptive finite element
approximations for the Kohn-Sham model. Based on the residual type a posteriori
error estimators proposed in this paper, we introduce an adaptive finite
element algorithm with a quite general marking strategy and prove the
convergence of the adaptive finite element approximations. Using D{\" o}rfler's
marking strategy, we then get the convergence rate and quasi-optimal
complexity. We also carry out several typical numerical experiments that not
only support our theory,but also show the robustness and efficiency of the
adaptive finite element computations in electronic structure calculations.Comment: 38pages, 7figure
A Deep Reinforcement Learning-Based Charging Scheduling Approach with Augmented Lagrangian for Electric Vehicle
This paper addresses the problem of optimizing charging/discharging schedules
of electric vehicles (EVs) when participate in demand response (DR). As there
exist uncertainties in EVs' remaining energy, arrival and departure time, and
future electricity prices, it is quite difficult to make charging decisions to
minimize charging cost while guarantee that the EV's battery
state-of-the-charge (SOC) is within certain range. To handle with this dilemma,
this paper formulates the EV charging scheduling problem as a constrained
Markov decision process (CMDP). By synergistically combining the augmented
Lagrangian method and soft actor critic algorithm, a novel safe off-policy
reinforcement learning (RL) approach is proposed in this paper to solve the
CMDP. The actor network is updated in a policy gradient manner with the
Lagrangian value function. A double-critics network is adopted to synchronously
estimate the action-value function to avoid overestimation bias. The proposed
algorithm does not require strong convexity guarantee of examined problems and
is sample efficient. Comprehensive numerical experiments with real-world
electricity price demonstrate that our proposed algorithm can achieve high
solution optimality and constraints compliance
Development of a Scaffold Design Model in Inter-school Collaboration Environment: A Design-based Research
This study examines the development of a theoretical framework for scaffold design in an inter-school collaboration environment. The research question primarily deals with how to design scaffolds for an Inter-school Collaborative Learning (ICL). Design-based research methodology was used in this study. Literature review, questionnaire survey, field survey, and interviews were used during the course of research. Forty-seven secondary schools in 25 provinces in China were selected and participated in the study. This paper reports the first circle of design-based research. Through design-based research, a scaffold design model was developed and revised. Eight key types of scaffolding for ICL were identified. Elaborated strategies and tools were summarized for implementation of these scaffolds
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