The present review study determines to scrutinize EFL teachers' optimism and commitment and their contribution to students' academic success. Academic optimism, as a new construct, is evolving from ...the examination of the positive psychology (PP), societal principal, and communal school assets that affect the attainment and success of all learners. In addition, within the past decades, commitment has received a great level of consideration, principally in the domain of structural research. The straightforward perseverance of this review is to extend the concept of academic optimism to individuals, that is, to hypothesize theoretical optimism and approve the efficacy of this paradigm at the instructor level in relation to students' academic success. According to the literature review, the definitions of these constructs, namely teachers' optimism and commitment, and students' academic success, as well as empirical studies in this domain are presented. As a conclusion, this study, to some extent, promotes the educators' mindfulness about their commitment. In this respect, pedagogical implications for teachers, school principals, teacher-trainers, and future researchers are presented, and new guidelines for further research are determined.
Accurate and stable short-term traffic flow prediction is an indispensable part in current intelligent transportation systems. In this paper, a novel short-term traffic flow forecasting model termed ...as EnLSTM-WPEO is proposed based on ensemble learning of long short term memory neural network (LSTM), no negative constraint theory (NNCT) weight integration and population extremal optimization (PEO) algorithm. In the first stage, a cluster of LSTMs is constructed to separately forecast with different time lag, which is a significant element to affect the prediction performance. In the second stage, the PEO-based NNCT weight integration strategy is introduced to determine the weight coefficients of the ensemble model. The simulation results for six different datasets from highways of Seattle have testified the superiority of the proposed EnLSTM-WPEO to other six popular traffic flow forecasting models in terms of two commonly used performance indices and three statistical tests.
With the rapid development of communication, control, and computer technology, traditional power systems have evolved into cyber-physical power system (CPPS). However, CPPS not only affords ...convenience but also introduces more cyber-attacks. Among many types of cyber-attacks, false data injection attacks (FDIAs) have drawn much attention in the CPPS security domain due to their stealthiness. Most FDIAs are based on the static model on a single snapshot and often ignore the reality of dynamically time-evolving CPPS. Accordingly, this article proposes a novel three-stage dynamic false data injection attack (DFDIA) model in CPPS by considering potential dynamic behaviors. To consider both attack location and attack amplitude, the designing DFDIA is formulated as two constrained single-objective optimization problems. Two versions of constrained differential evolution are presented as the solver to determine the attack location and optimize the attack vector for collaboratively altering the meter measurements. Then, an interval state forecasting-based countermeasure is proposed to detect the established DFDIA. In this detector, the variation bounds of state values are determined via ensemble deep learning-based state forecasting method. Finally, extensive simulation results on several IEEE bus systems demonstrate the feasibility of DFDIA and the effectiveness of the defense mechanism.
As the next-generation power grids, smart grids are integrated with advanced information and communication technology (ICT) to make the grid more efficient and stable than conventional power systems. ...Given the mounting cyber-attack threats, these critical ICT systems create great security issues for smart grids. Additionally, the clever attackers have the ability to not only access and monitor the smart grid, but also hack it by launching well-established cyber-attacks. Thus, this article is devoted to understanding the potential stealthy cyber-attack and its countermeasure. First, this article proposes a stealthy sparse cyber-attack model in an ac smart grid by considering both the residual test-based detector and the interval-state-estimation-based detector, which is not considered in previous studies. The design model is formulated as a constrained optimization problem by minimizing the number of contaminated meters, where the characteristics of two types of detector are considered simultaneously as the constraints for the first time. A constrained differential evolution (CDE) is proposed as the solver because the optimization problem is NP-hard. Then, a generalized-cumulative-sum-based detector is developed to detect the proposed cyber-attacks, where a fractional-order state transition matrix is originally introduced into the estimator to describe the dynamics of the power system. Numerical studies illustrate the feasibility of CDE-based stealthy sparse cyber-attacks and the effectiveness of the proposed countermeasure.
A hybrid generator with a photovoltaic energy conversion system is proposed with supercapacitors and lead-acid batteries in a dc-coupled structure. The objective of this system is to supply the ...prescribed reactive and active power to the grid. This paper focuses on the strategy, which makes it possible to ensure a high battery state of charge and overcharge security by designing a dedicated local control system. A continuous dynamic model and a control design of the power system studied are proposed in this paper. Simulation and experimental results illustrate the performances obtained.
The current treatment strategies in advanced malignancies remain limited. Notably, immunotherapies have raised hope for a successful control of these advanced diseases, but their therapeutic ...responses are suboptimal and vary considerably among individuals. Tumor-associated macrophages (TAMs) are a major component of the tumor microenvironment (TME) and are often correlated with poor prognosis and therapy resistance, including immunotherapies. Thus, a deeper understanding of the complex roles of TAMs in immunotherapy regulation could provide new insight into the TME. Furthermore, targeting of TAMs is an emerging field of interest due to the hope that these strategies will synergize with current immunotherapies. In this review, we summarize recent studies investigating the involvement of TAMs in immune checkpoint inhibition, tumor vaccines and adoptive cell transfer therapies, and discuss the therapeutic potential of targeting TAMs as an adjuvant therapy in tumor immunotherapies.
In cyber-physical power systems (CPPSs), additional control as the compensating control plays a very important part in load frequency control (LFC) systems. The additional control in the LFC system ...is constrained by limited communication resources and cyber-attacks, which may cause performance degradation or destabilize the system. Accordingly, this paper proposes resilient event-triggered LFC for CPPSs with an additional control loop under denial-of-service (DoS) attacks. Firstly, a resilient event-triggered communication scheme is presented to reduce the occupation of communication resources under DoS attacks in the additional control loop. Then, different from existing event-triggered LFC systems, this paper establishes a novel switched LFC system model, where the resilient event generator is integrated into an additional control loop when suffering from DoS attacks. It is the first time that the additional control loop of the LFC system simultaneously considers communication resources and cyber-security. Furthermore, we derive exponential stabilization criteria by applying the Lyapunov stability theory based on the established model. Criteria are derived to obtain the weighting matrix and controller gain simultaneously by applying the linear matrix inequality technique. Finally, a one-area and two multi-area CPPSs with the additional control loop under DoS attacks are used to testify the availability of the proposed resilient event-triggered LFC scheme.
Catalysts capable of electrochemical overall water splitting in acidic, neutral, and alkaline solution are important materials. This work develops bifunctional catalysts with single atom active sites ...through a pyrolysis-free route. Starting with a conjugated framework containing Fe sites, the addition of Ni atoms is used to weaken the adsorption of electrochemically generated intermediates, thus leading to more optimized energy level sand enhanced catalytic performance. The pyrolysis-free synthesis also ensured the formation of well-defined active sites within the framework structure, providing ideal platforms to understand the catalytic processes. The as-prepared catalyst exhibits efficient catalytic capability for electrochemical water splitting in both acidic and alkaline electrolytes. At a current density of 10 mA cm
, the overpotential for hydrogen evolution and oxygen evolution is 23/201 mV and 42/194 mV in 0.5 M H
SO
and 1 M KOH, respectively. Our work not only develops a route towards efficient catalysts applicable across a wide range of pH values, it also provides a successful showcase of a model catalyst for in-depth mechanistic insight into electrochemical water splitting.
The development of energy management tools for next-generation PhotoVoltaic (PV) installations, including storage units, provides flexibility to distribution system operators. In this paper, the ...aggregation and implementation of these determinist energy management methods for business customers in a microgrid power system are presented. This paper proposes a determinist energy management system for a microgrid, including advanced PV generators with embedded storage units and a gas microturbine. The system is organized according to different functions and is implemented in two parts: a central energy management of the microgrid and a local power management at the customer side. The power planning is designed according to the prediction for PV power production and the load forecasting. The central and local management systems exchange data and order through a communication network. According to received grid power references, additional functions are also designed to manage locally the power flows between the various sources. Application to the case of a hybrid supercapacitor battery-based PV active generator is presented.
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