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Abstract Tuning the topology of two‐dimensional (2D) covalent organic frameworks (COFs) is of paramount scientific interest but remains largely unexplored. Herein, we present a site‐selective synthetic strategy that enables the tuning of 2D COF topology by simply adjusting the molar ratio of an amine‐functionalized dihydrazide monomer (NH₂−Ah) and 4,4′,4′′‐(1,3,5‐triazine‐2,4,6‐triyl)tribenzaldehyde (Tz). This approach resulted in the formation of two distinct COFs: a clover‐like 2D COF with free amine groups (NH₂−Ah−Tz) and a honeycomb‐like COF without amine groups (Ah−Tz). Both COFs exhibited good crystallinity and moderate porosity. Remarkably, the clover‐shaped NH₂−Ah−Tz COF, with abundant free amine groups, displayed significantly enhanced adsorption capacities toward crystal violet (CV, 261 mg/g) and congo red (CR, 1560 mg/g) compared to the non‐functionalized honeycomb‐like Ah−Tz COF (123 mg/g for CV and 1340 mg/g for CR), underscoring the pivotal role of free amine functional groups in enhancing adsorption capacities for organic dyes. This work highlights that the site‐selective synthetic strategy paves a new avenue for manipulating 2D COF topology by adjusting the monomer feeding ratio, thereby modulating their adsorption performances toward organic dyes. 

This paper proposes a novel multi-objective inverse optimization method for high-speed interconnects based on a cascaded deep neural network (DNN) structure, which can efficiently optimize characteristic impedance, insertion loss, and far-end crosstalk (FEXT) simultaneously. Parameter optimization for high-speed interconnects is essential to the signal integrity and electrical performance of complex designs such as multilayer printed circuit boards (PCBs) and chiplets. Conventional optimization approaches often rely on numerous optimization iterations, which is highly time-consuming, especially in highdimensional parameter spaces. This paper proposes a novel DNNbased method by cascading an inverse-prediction network and a forward-prediction network to achieve multi-objective optimization for characteristic impedance, insertion loss, and FEXT by optimizing the trace width, trace spacing, and pair-topair distance. Further, by incorporating an integer programming technique, parameter optimization of multilayer PCBs, including the PCB stackup and design parameters of each signal layer, can be accomplished in seconds, much more efficiently than the conventional optimization approaches. 

De-embedding techniques have been introduced to evaluate the real electrical performances of a device under test (DUT), e.g., the traditional thru-reflect-line and short-open-load-thru standards, where the transfer matrix (T-matrix) and its inverse form are adopted in the mathematical process. A DUT may have three coupled ports in the fields of radio frequency and electromagnetic compatibility. The symmetry in the corresponding S-matrix breaks down, because the numbers of incident and reflected ports are not equal. Thus, it leads to a nonsquare T-matrix by definition. Given that the inverse expression of a nonsquare matrix does not exist, the conventional de-embedding methods are inapplicable for a coupled three-port network. In this article, a de-embedding algorithm, which is feasible for coupled three-port devices, is proposed and verified through the measurement. The proposed de-embedding technique may also be applied on devices with more than three ports. 

An accurate and broadband modeling methodology for a typical permanent magnet synchronous motor (PMSM) in a vehicular three-phase braking system is proposed for the first time to improve the accuracy of induced electromagnetic interference (EMI) in three-phase motor systems. The proposed model is verified by measurement from dc to 120 MHz both in common- and differential-mode current measurement of the three-phase motor under study. The proposed model can be used in analysis and prediction of the electromagnetic noise of the motor-drive braking system. The model can also be incorporated into frequency- and time-domain simulations. The modeling approach is based on the vector fitting technique of measured three-phase motor impedance and S-parameter, where the three-phase PMSM is modeled as a multiport device. In addition, the proposed modeling method for the PMSM can be used for different types of three-phase motors for EMI simulations and analysis.