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When False Data Injection (FDI) attacks inject false data into the controllers of a microgrid, it can lead the controllers to make decisions based on inaccurate information, ultimately resulting in system collapse. This study presents a novel approach to dynamically adjust output voltage in Campus Microgrids (CMG). Initially, we use feedback linearization techniques to address the inherent nonlinear complexities in Distributed Generation (DG) dynamics. Moreover, during voltage regulation, controllers and sensors may be susceptible to FDI attacks. To address this, an elastic follower observer is introduced to mitigate the impact of false information injection attacks on voltage coordination, thus ensuring the robustness and stability of the system. Notably, our method reduces dependence on global information and fault boundaries within the communication network, thereby enhancing system elasticity and efficiency. In conclusion, through comprehensive simulation experiments, we evaluate the effectiveness and performance of our proposed strategy. The simulation results validate the success of our approach in voltage regulation and its efficiency in fault management. These findings bear significant implications for the advancement of voltage regulation strategies in distributed generation systems. [ABSTRACT FROM AUTHOR]

Amidst the tremendous evolution of the digital economy and the expedited establishment of a new development paradigm, the use of artificial intelligence (AI) technologies holds significant importance in achieving superior economic development. While much of the previous research focused on the macroeconomic impact of AI, this study examined how AI technology affects food processing firm performance, productivity, and labor skill structure at the food processing firm level. This study utilized panel data from listed food processing enterprises in Shanghai and Shenzhen spanning from 2010 to 2021, performing textual analysis on the annual reports of listed companies and then creating enterprise-level AI indicators to empirically examine the influence of AI applications on enterprise performance and its underlying mechanisms. The findings indicate a substantial improvement in business performance due to the application of artificial intelligence, which is a conclusion corroborated through a series of stability tests. Exploring channels and mechanisms, the analysis revealed that AI-driven advancements in production technologies stimulated the requirement for highly skilled labor, thereby inducing shifts in the labor force's structure. Further investigation demonstrated that artificial intelligence contributed to enhancing the total factor productivity, consequently bolstering the overall enterprise performance. A heterogeneity analysis showed that firm-level factors, such as the nature of property rights and factor intensity, had an impact on the influence of AI on firm performance. In addition, the geographic location and time of year of a company also had impacts on the productivity benefits of artificial intelligence. This research deepened the cognition and understanding of the role played by AI in the production process at the micro-enterprise level and provided suggestions for promoting the development of artificial intelligence technologies at the micro-enterprise level, which will facilitate the transformation of the labor structure to further augment enterprise efficiency. [ABSTRACT FROM AUTHOR]

The frequent occurrence of urban flooding in recent years has resulted in significant damage to ground-level infrastructure and poses a substantial threat to the metro system. As the central city's core transportation network for public transit, this threat can have unpredictable consequences on travel convenience and public safety. Therefore, assessing the risk of urban flooding in the metro system is of utmost importance. This study is the first of its kind to employ comprehensive natural disaster risk assessment theory, establishing an assessment database with 22 indicators. We propose a GIS-based method combined with the analytical hierarchy process (AHP) and an improved entropy weight method to comprehensively evaluate the urban flood risk in Changchun City's metro systems in China. This study includes a total of nine metro lines, including those that are currently operational as well as those that are in the planning and construction phases, situated in six urban areas of Changchun City. In this study, we utilize the regional risk level within the 500 m buffer zone of the metro lines to represent the flood risk of the metro system. The proposed method assesses the flood risk of Changchun's rail transit system. The results reveal that over 30% of Changchun's metro lines are located in high-risk flood areas, mainly concentrated in the densely populated and economically prosperous western part of the central city. To validate the risk assessment, we vectorized the inundation points and overlaid them with the regional flood risk assessment results, achieving a model accuracy of over 90%. As no large-scale flood events have occurred in the Changchun rail transit system, we employed receiver operating characteristic (ROC) curves to verify the accuracy of the flood risk assessment model, resulting in an accuracy rate of 91%. These findings indicate that the present study is highly reliable and can provide decision makers with a scientific basis for mitigating future flood disasters. [ABSTRACT FROM AUTHOR]

The article titled "Computational Analysis of Variational Inequalities Using Mean Extra-Gradient Approach" has been retracted by the Mathematics Editorial Office. Concerns were raised about significant overlap with a previous publication by a different group. An investigation confirmed the overlap and lack of appropriate citation, leading to the decision to retract the article in accordance with MDPI's retraction policy and the Committee on Publication Ethics' retraction guidelines. The authors did not provide a comment on this decision. [Extracted from the article]

Objective: To assess and compare the therapeutic effects of Anterior Cervical Discectomy and Fusion (ACDF) and Cervical Laminectomy and Fusion (CLF) in the treatment of 4‐level cervical. Methods: We performed a retrospective review on 39 patients with 4‐level CSM who underwent ACDF or CLF in the Third Hospital of Hebei Medical University from January 2010 to December 2018. The patients were divided into ACDF group and CLF group according to the treatment. The operative index was evaluated based on intraoperative blood loss and operation time. The functional outcomes including Japanese Orthopedic Association (JOA) score and visual analogue scale (VAS) of axial pain were compared. The Cobb angle, Cobb angle improvement rate, range of motion (ROM) and ROM loss ratio were measured for radiographic evaluation. Results: No major complications or deaths occurred. The average age at baseline was 55 years. There was no significant difference between the ACDF and CLF group in follow‐up time (26.29 months, 25.39 months, P > 0.05). The intraoperative blood loss was higher in the CLF group than in the ACDF group (692.67 ± 38.68 vs 392.14 ± 128.06, P < 0.05). The operation time was longer in the CLF group than in the ACDF group (206.60 ± 49.37 vs 172.64 ± 31.96, P < 0.05). Significant improvements in the VAS and JOA scores were observed in both groups (P < 0.05). No significant difference in VAS was found between the ACDF and CLF groups (P < 0.05). There was a significantly larger improvement rate of JOA score in the ACDF group than in the CLF group (60.9% ± 9.57% vs 31.5% ± 15.70%, P < 0.05). There were two (9.6%) cases with complications In the ACDF group, including one (4.8%) case of dysphagia and one (4.8%) case of pharyngodynia. In the CLF group, two patients (11.1%) developed C5 palsy. No significant difference in the incidence of complications, ROM loss ratio and Cobb angle improvement rate was found between group ACDF and group CLF (all P < 0.05). Conclusion: Both ACDF and CLF were effective in the treatment of multi‐level cervical spondylosis and ACDF is more suitable for patients with 4‐level CSM. [ABSTRACT FROM AUTHOR]