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The investigation of the paradox and robustness about the traffic network is an important branch of the traffic assignment. In this paper, Braess’ paradox and robustness of the dynamic traffic network are analyzed by the dynamic traffic assignment models. In addition, the relationship of total costs with different traffic assignment models is discussed. The results show that the paradox only occurs in certain range; the robustness of the network and the relationship of total traffic costs are changed as the traffic demand changes, which provides theoretical guidance for the urban transportation planning.

The increasing integration of distributed photovoltaics may further aggravate the over‐voltage and three‐phase unbalance issues of low‐voltage distribution networks with three‐phase four‐wire structures. The voltage control method based on the AC and DC side power flow control and the three‐phase power control capability of voltage source converter in hybrid AC/DC low‐voltage distribution networks is a solution for the improvement of the above power quality issues. In this paper, an accurately improved sensitivity matrix calculation method considering shunt admittance based on the ABCD parameters is proposed in hybrid AC/DC low‐voltage distribution networks with a three‐phase four‐wire structure. The presented ABCD parameters of the feeders consider the influence of the coupling effect among phases and the neutral line on sensitivity calculation, which makes the sensitivity calculation simple. Then, a power‐voltage control method for voltage source converters based on three‐phase four‐wire sensitivity matrices of the AC side is proposed considering the constraints from the voltage source converter and DC side power flow in hybrid AC/DC low‐voltage distribution networks, which can effectively address the over‐voltage and unbalanced issues. Simulations are performed to verify the proposed sensitivity calculation method and voltage control method.

We propose a dynamic traffic network model and give the equilibrium condition and the equivalent variational inequality of the network. In this model, instead of the influence of inflow rate and output rate on the link congestion, the influence of the adjacent links at the same paths is considered; in this case, the equivalence between the equilibrium condition and the variational inequality is proved. Then we take an example about the paradox using the variational inequality and find that the probability and the severity that Braess’ paradox occurs change with the influence of other links changing. Subsequently, we discuss the influence of other links on whether the adding link works under the dynamic system optimal. At last, we give the relationship between the total congestion under dynamic user equilibrium and that under dynamic system optimal. The results imply that we should take some methods and adjust the interaction between links rationally with the dynamic change of traffic situations.

Metal-phenolic networks (MPNs) have been exploited to be a versatile coating film to fabricate core-shell structure due to their general adherent properties. Herein, gold nanocuboid (GNCB) wrapped by MPNs (GNCB at MPNs) are prepared by a facile encapsulation method for surface-enhanced Raman scattering (SERS) analysis. The MPN coating not only reshapes the electric field distribution around the nanostructures but also allows the substrate to adsorb more analytes, both of which contribute to the superior SERS activity of GNCB at MPNs. The SERS signals induced by plasmonic nanostructures increase four- to sixfold after MPN coating, reaching a maximum Raman enhancement factor calculated to be 9.47 × 1 0 8 . Moreover, the core-shell SERS substrate also demonstrates improved biocompatibility (∼fivefold increase) that facilitates the reliable SERS analysis of cancer cells and further diverse biomedical applications.

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The manual inspection for the damage state of the electric energy metering box consumes a lot of time, the workload is large, and the data storage is difficult. In order to solve these problems, this paper proposes an automatic detection method for the damage state of the electric energy metering box based on the YOLOv5 algorithm. The actual metering box pictures taken by the operation and maintenance inspectors are used as the training set, LabelImage is used to annotate the data set, and YOLOv5s model is used to train the data set. The experimental results show that the method proposed in this paper can accurately mark the position of the metering box lid and accurately predict its damage state. The average accuracy reaches 98%, which can meet the requirements for the detection accuracy of the power metering box damage state in the operation and maintenance inspection work.

Firstly, through the analysis of the life cycle of a highway project, this paper identified risks influencing construction schedule which set up a foundation for further establishment of a risk index system. Secondly, based on the established risk index system, this paper calculated and evaluated indicators of risks identified through probability analysis and fuzzy logic methods which became simpler after adoption of principal component analysis (PCA). Finally, the PCA-fuzzy probability analysis method is proved feasible and practicable by case study.