capacity model
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2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Baiqun Ding ◽  
Liu Yang ◽  
He Xu ◽  
Yongming He

To reduce the risk of queuing overflow on the urban minor road at the intersection under supersaturation where the capacity of the arterial and minor roads shows extreme disparity, reduce the adverse effects caused by long queues of vehicles on the minor road, and comprehensively balance the multiobjective requirements such as priority of the main road, queuing restrictions, and delay on the minor road, the minor road queue model at the end of red, a road remaining capacity model, and multiparameter coordinated signal control model were established, and a multiobjective genetic algorithm was used to optimize this solution. As an example, the multiparameter coordinated control strategy decreased the delay per vehicle by approximately 17% and the queue length by approximately 30%–50% on the minor road and slightly increased the delay per vehicle at the intersection and the length on the main road queue. This control strategy can make full use of the capacity of the main road to control the queue length on the minor road, effectively reduce the risk of minor road queue overflow blocking local road network traffic operation involved, and comprehensively balance the traffic demand between arterial and minor roads. It provides a reference control method for coping with the transfer of the main traffic contradiction under the oversaturated state of the road intersection with large disparity.


Electronics ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 17
Author(s):  
Peixiao Fan ◽  
Song Ke ◽  
Salah Mohamed Kamel Mohamed Hassan ◽  
Jun Yang ◽  
Yonghui Li ◽  
...  

Frequency and voltage deviation are important standards for measuring energy indicators. It is important for microgrids to maintain the stability of voltage and frequency (VF). Aiming at the VF regulation of microgrid caused by wind disturbance and load fluctuation, a comprehensive VF control strategy for an islanded microgrid with electric vehicles (EVs) based on Deep Deterministic Policy Gradient (DDPG) is proposed in this paper. First of all, the SOC constraints of EVs are added to construct a cluster-EV charging model, by considering the randomness of users’ travel demand and charging behavior. In addition, a four-quadrant two-way charger capacity model is introduced to build a microgrid VF control model including load, micro gas turbine (MT), EVs, and their random power increment constraints. Secondly, according to the two control goals of microgrid frequency and voltage, the structure of DDPG controller is designed. Then, the definition of space, the design of global and local reward functions, and the selection of optimal hyperparameters are completed. Finally, different scenarios are set up in an islanded microgrid with EVs, and the simulation results are compared with traditional PI control and R(λ) control. The simulation results show that the proposed DDPG controller can quickly and efficiently suppress the VF fluctuations caused by wind disturbance and load fluctuations at the same time.


2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
Haoli Ren ◽  
Hailan Li ◽  
Kongyang Peng

With the development of vocational education, it is necessary to construct the pattern of lifelong learning. To push delivery learning resources and provide a learning environment, it is necessary to innovate in-service learning mode. According to the characteristics of the aerospace position, the capacity model was studied and proposed. Based on the ability model, the intelligent in-service learning model is studied and proposed to improve the precision service quality. From the angle of principle and learning process, this paper discusses the intelligent in-service learning mode of including the learning model based on knowledge map and the learning model based on seminar hall. The framework of the job knowledge map is constructed according to the post ability model which is based on professional knowledge, professional skills, and professional quality. The intelligent on-the-job learning model includes four elements: (i) learning platform, (ii) learning resources, (iii) learning methods, and (iv) learning evaluation. The learning portrait can record and visualize the information of learning, including content, activities, and effects.


2021 ◽  
Author(s):  
ANTONIO PRATELLI ◽  
LORENZO BROCCHINI ◽  
NICOLA FRANCESCONI

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. 213-213
Author(s):  
Julie Kirsch

Abstract Racial minorities and educationally disadvantaged experienced more housing loss, unemployment, and financial strain during the 2007-2009 Great Recession. These hardships may heighten stress and amplify persistent and growing health inequities, which were further worsened by the recent COVID-19 pandemic. It is therefore essential to identify factors that contribute to individual differences in vulnerability so that more effective interventions can be implemented, especially in older adult populations who may face unique economic hardships tied to age discrimination. According to the reserve capacity model, higher levels of psychosocial resources, including psychological well-being, can protect against the negative health outcomes related to heightened stress exposure. This study tested the intersections between recession hardship, pre-existing vulnerability defined as racial and educational disadvantage, and psychological well-being as predictors of biological indicators of chronic allostatic load. Chronic allostatic load was assessed with cardiovascular reactivity and recovery to acute mental stress and systemic inflammation (basal indicators of C-reactive protein and interleukin 6). Biological data came from a national sample of adults known as the Midlife in the US Study ( MIDUS; age = 25-75, N=863) that completed assessments after the recession. Multiple regression models revealed that more widespread recession hardship predicted greater biological dysregulation. Tests of three-way interactions revealed that the association between recession hardship and biological dysregulation was strongest among respondents with combined disadvantages of low educational status and low levels of psychological well-being. This study connected a major economic event to individual variation in health vulnerability and identified potential biological pathways to future disease outcomes.


2021 ◽  
Author(s):  
Ulises Sepúlveda ◽  
Pablo A. Mendoza ◽  
Naoki Mizukami ◽  
Andrew J. Newman

Abstract. Despite the Variable Infiltration Capacity (VIC) model being used for decades in the hydrology community, there are still model parameters whose sensitivities remain unknown. Additionally, understanding the factors that control spatial variations in parameter sensitivities is crucial given the increasing interest to obtain spatially coherent parameter fields over large domains. In this study, we investigate the sensitivities of 43 soil, vegetation and snow parameters in the VIC model for 101 catchments spanning the diverse hydroclimates of continental Chile. We implement a hybrid local-global sensitivity analysis approach, using eight model evaluation metrics to quantify sensitivities, with four of them formulated from runoff time series; two characterizing snow processes, and the remaining two based on evaporation processes. Our results confirm an over-parameterization for the processes analysed here, with only 12 (i.e., 28 %) parameters found as sensitive, distributed among soil (7), vegetation (2) and snow (3) model components. Correlation analyses show that climate variables – in particular, mean annual precipitation and aridity index – are the main controls on parameter sensitivities. Additionally, our results highlight the influence of the leaf area index on simulated hydrologic processes – regardless on the dominant climate types – and the relevance of hard-coded snow parameters. Based on correlation results and the interpretation of spatial sensitivity patterns, we provide guidance on the most relevant parameters for model calibration according to the target processes and the prevailing climate type. Overall, the results presented here contribute to improved understanding of model behaviour across watersheds with diverse physical characteristics that encompass a wide hydroclimatic gradient from hyper-arid to humid systems.


Entropy ◽  
2021 ◽  
Vol 23 (11) ◽  
pp. 1384
Author(s):  
Jesse Hoey

In this paper, I investigate a connection between a common characterisation of freedom and how uncertainty is managed in a Bayesian hierarchical model. To do this, I consider a distributed factorization of a group’s optimization of free energy, in which each agent is attempting to align with the group and with its own model. I show how this can lead to equilibria for groups, defined by the capacity of the model being used, essentially how many different datasets it can handle. In particular, I show that there is a “sweet spot” in the capacity of a normal model in each agent’s decentralized optimization, and that this “sweet spot” corresponds to minimal free energy for the group. At the sweet spot, an agent can predict what the group will do and the group is not surprised by the agent. However, there is an asymmetry. A higher capacity model for an agent makes it harder for the individual to learn, as there are more parameters. Simultaneously, a higher capacity model for the group, implemented as a higher capacity model for each member agent, makes it easier for a group to integrate a new member. To optimize for a group of agents then requires one to make a trade-off in capacity, as each individual agent seeks to decrease capacity, but there is pressure from the group to increase capacity of all members. This pressure exists because as individual agent’s capacities are reduced, so too are their abilities to model other agents, and thereby to establish pro-social behavioural patterns. I then consider a basic two-level (dual process) Bayesian model of social reasoning and a set of three parameters of capacity that are required to implement such a model. Considering these three capacities as dependent elements in a free energy minimization for a group leads to a “sweet surface” in a three-dimensional space defining the triplet of parameters that each agent must use should they hope to minimize free energy as a group. Finally, I relate these three parameters to three notions of freedom and equality in human social organization, and postulate a correspondence between freedom and model capacity. That is, models with higher capacity, have more freedom as they can interact with more datasets.


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