Pro-aromatic bisphenaleno-thieno[3,2-b]thiophene versus anti-aromatic bisindeno-thieno[3,2-b]thiophene: different ground-state properties and applications in field-effect transistors.

Shi, Xueliang,Lee, Sangsu,Son, Minjung,Zheng, Bin,Chang, Jingjing,Jing, Linzhi,Huang, Kuo-Wei,Kim, Dongho,Chi, Chunyan The Royal Society of Chemistry 2015 Chemical communications Vol.51 No.67

<P>A pro-aromatic bisphenaleno-thieno[3,2-b]thiophene (BPT-TIPS) was synthesized and compared with an anti-aromatic bisindeno-thieno[3,2-b]thiophene (S2-TIPS). BPT-TIPS showed larger diradical character, stronger absorption, longer excited state lifetime and better redox amphotericity than S2-TIPS.</P>

Benzo-thia-fused [ <i>n</i> ]thienoacenequinodimethanes with small to moderate diradical characters: the role of pro-aromaticity <i>versus</i> anti-aromaticity

Shi, Xueliang,Quintero, Estefaní,a,Lee, Sangsu,Jing, Linzhi,Herng, Tun Seng,Zheng, Bin,Huang, Kuo-Wei,Ló,pez Navarrete, Juan T.,Ding, Jun,Kim, Dongho,Casado, Juan,Chi, Chunyan Royal Society of Chemistry 2016 Chemical Science Vol.7 No.5

<▼1><P>Pro-aromatic <B>Th<I>n</I>-TIPS</B> exhibits distinctly different physical properties from anti-aromatic <B>S<I>n</I>-TIPS</B>.</P></▼1><▼2><P>Open-shell singlet diradicaloids have recently received much attention due to their unique optical, electronic and magnetic properties and promising applications in materials science. Among various diradicaloids, quinoidal π-conjugated molecules have become the prevailing design. However, the need for a fundamental understanding on how the fusion mode and pro-aromaticity/anti-aromaticity affect their diradical character and physical properties remains unaddressed. In this work, a series of pro-aromatic benzo-thia-fused [<I>n</I>]thienoacenequinodimethanes (<B>Th<I>n</I>-TIPS</B> (<I>n</I> = 1–3) and <B>BDTh-TIPS</B>) were synthesized and compared with the previously reported anti-aromatic bisindeno-[<I>n</I>]thienoacenes (<B>S<I>n</I>-TIPS</B>, <I>n</I> = 1–4). The ground-state geometric and electronic structures of these new quinoidal molecules were systematically investigated by X-ray crystallographic analysis, variable temperature NMR, ESR, SQUID, Raman, and electronic absorption spectroscopy, assisted by DFT calculations. It was found that the diradical character index (<I>y</I><SUB>0</SUB>) increased from nearly zero for <B>Th1-TIPS</B> to 2.4% for <B>Th2-TIPS</B>, 18.2% for <B>Th3-TIPS</B>, and 38.2% for <B>BDTh-TIPS</B>, due to the enhanced aromatic stabilization. Consequently, with the extension of molecular size, the one-photon absorption spectra are gradually red-shifted, the two-photon absorption (TPA) cross section values increase, and the singlet excited state lifetimes decrease. By comparison with the corresponding anti-aromatic analogues <B>S<I>n</I>-TIPS</B> (<I>n</I> = 1–3), the pro-aromatic <B>Th<I>n</I>-TIPS</B> (<I>n</I> = 1–3) exhibit larger diradical character, longer singlet excited state lifetime and larger TPA cross section value. At the same time, they display distinctively different electronic absorption spectra and improved electrochemical amphotericity. Spectroelectrochemical studies revealed a good linear relationship between the optical energy gaps and the molecular length in the neutral, radical cationic and dicationic forms. Our research work discloses a significant difference between the pro-aromatic and anti-aromatic quinoidal compounds and provides guidance for the design of new diradicaloids with desirable properties.</P></▼2>

Optimized junction temperature fluctuation suppression technique for SiC MOSFETs in a wireless charging system

Ruoyin Wang,Xueliang Huang,Jiacheng Li 전력전자학회 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.5

The problem of SiC MOSFET junction temperature fluctuation in wireless charging systems must be addressed immediately. The existing temperature fluctuation suppression technique requires a large number of additional switches and capacitors. This study further optimizes the temperature fluctuation tracking suppression (TFTS) strategy. This method realizes closedloop temperature adjustment and greatly simplifies the system structure. In addition, an optimized TFTS (OTFTS) strategy combined with an optimized proportional–integral–derivative control method is proposed to solve integral saturation and the subsequent control instability phenomenon. Then, a 5.5 kW experimental system is built. Results show that the OTFTS strategy eliminates 17.9 °C junction temperature fluctuation on the basis of reducing the hardware cost. It also has a good dynamic response and junction temperature fluctuation suppression effect.

Transition Control of Standby and Operation Modes of Wireless Charging System for Inspection Robots

Han Liu,Linlin Tan,Xueliang Huang,Dariusz Czarkowski 전력전자학회 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.3

To solve the problems in the contact charging of inspection robots, a wireless charging system for inspection robots and a control strategy are introduced in this paper. Circuit models of a wireless power system with a compound compensation circuit and a three-phase Class-D resonant inverter are set up based on circuit theory. An output voltage control method based on the equal spread regulation of the phase difference between adjacent phases and the parameter correction method in the primary compound compensation circuit are proposed. The dynamic characteristics of the key parameters varying with the secondary coil position are obtained to further investigate the adaptive location scheme during the access and exit processes of moving robots. Combining the output voltage control method and the adaptive location scheme, a transition control strategy for the standby and operation modes of the wireless charging systems for inspection robots is put forward to realize the system characteristics including the low standby power in the standby mode and the high receiving power in the operation mode. Finally, experiments are designed and conducted to verify the correctness of the theoretical research.

Product Adoption Maximization Leveraging Social Influence and User Interest Mining

( Ping Ji ),( Hui Huang ),( Xueliang Liu ),( Xueyou Hu ) 한국인터넷정보학회 2021 KSII Transactions on Internet and Information Syst Vol.15 No.6

A Social Networking Service (SNS) platform provides digital footprints to discover users’ interests and track the social diffusion of product adoptions. How to identify a small set of seed users in a SNS who is potential to adopt a new promoting product with high probability, is a key question in social networks. Existing works approached this as a social influence maximization problem. However, these approaches relied heavily on text information for topic modeling and neglected the impact of seed users’ relation in the model. To this end, in this paper, we first develop a general product adoption function integrating both users’ interest and social influence, where the user interest model relies on historical user behavior and the seed users’ evaluations without any text information. Accordingly, we formulate a product adoption maximization problem and prove NP-hardness of this problem. We then design an efficient algorithm to solve this problem. We further devise a method to automatically learn the parameter in the proposed adoption function from users’ past behaviors. Finally, experimental results show the soundness of our proposed adoption decision function and the effectiveness of the proposed seed selection method for product adoption maximization.

A Topological Transformation and Hierarchical Compensation Capacitor Control in Segmented On-road Charging System for Electrical Vehicles

Han Liu,Linlin Tan,Xueliang Huang,Jinpeng Guo,Changxin Yan,Wei Wang 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.4

Experiencing power declines when the secondary coil is at the middle position between two primary coils is a serious problem in segmented on-road charging systems with a single energized segmented primary coil. In this paper, the topological transformation of a primary circuit and a hierarchical compensation capacitor control are proposed. Firstly, the corresponding compensation capacitors and receiving powers of different primary structures are deduced under the condition of a fixed frequency. Then the receiving power characteristics as a function of the position variations in systems with a single energized segmented primary coil and those with double segmented primary coils are analyzed comparatively. A topological transformation of the primary circuit and hierarchical compensation capacitor control are further introduced to solve the foregoing problem. Finally, an experimental prototype with the proposed topological transformation and hierarchical compensation capacitor control is carried out. Measured results show that the receiving power is a lot more stable in the movement of the secondary coil. It is a remarkable fact that the receiving power rises from 10.8W to 19.2W at the middle position between the two primary coils. The experimental are in agreement with the theoretical analysis.

Transition Control of Standby and Operation Modes of Wireless Charging System for Inspection Robots

Liu, Han,Tan, Linlin,Huang, Xueliang,Czarkowski, Dariusz The Korean Institute of Power Electronics 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.3

To solve the problems in the contact charging of inspection robots, a wireless charging system for inspection robots and a control strategy are introduced in this paper. Circuit models of a wireless power system with a compound compensation circuit and a three-phase Class-D resonant inverter are set up based on circuit theory. An output voltage control method based on the equal spread regulation of the phase difference between adjacent phases and the parameter correction method in the primary compound compensation circuit are proposed. The dynamic characteristics of the key parameters varying with the secondary coil position are obtained to further investigate the adaptive location scheme during the access and exit processes of moving robots. Combining the output voltage control method and the adaptive location scheme, a transition control strategy for the standby and operation modes of the wireless charging systems for inspection robots is put forward to realize the system characteristics including the low standby power in the standby mode and the high receiving power in the operation mode. Finally, experiments are designed and conducted to verify the correctness of the theoretical research.

A Topological Transformation and Hierarchical Compensation Capacitor Control in Segmented On-road Charging System for Electrical Vehicles

Liu, Han,Tan, Linlin,Huang, Xueliang,Guo, Jinpeng,Yan, Changxin,Wang, Wei The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.4

Experiencing power declines when the secondary coil is at the middle position between two primary coils is a serious problem in segmented on-road charging systems with a single energized segmented primary coil. In this paper, the topological transformation of a primary circuit and a hierarchical compensation capacitor control are proposed. Firstly, the corresponding compensation capacitors and receiving powers of different primary structures are deduced under the condition of a fixed frequency. Then the receiving power characteristics as a function of the position variations in systems with a single energized segmented primary coil and those with double segmented primary coils are analyzed comparatively. A topological transformation of the primary circuit and hierarchical compensation capacitor control are further introduced to solve the foregoing problem. Finally, an experimental prototype with the proposed topological transformation and hierarchical compensation capacitor control is carried out. Measured results show that the receiving power is a lot more stable in the movement of the secondary coil. It is a remarkable fact that the receiving power rises from 10.8W to 19.2W at the middle position between the two primary coils. The experimental are in agreement with the theoretical analysis.

Design and optimization of novel transceiver device for one‑way single‑wire power transfer

Yang Li,Taocheng Hu,Xueliang Wang,Yujie Zhai,Yao Li,Wenxin Huang,Zhigang Lou 전력전자학회 2023 JOURNAL OF POWER ELECTRONICS Vol.23 No.10

The further development of wireless power transfer technology is hindered by the limiting relationship between transmission distance, transmission efficiency, and size of the coupling mechanism. Thus, a feasible solution was provided by one-way single-wire power transfer. First, a horn-type mode conversion device was proposed in this study by analyzing the principle of one-way single-wire power transfer. Second, the system structure was designed to save materials and reduce the volume of space. The transmission efficiency of the system was improved, and the operating frequency was reduced by optimizing the parameters of the mode conversion device. Finally, the feasibility and structural applicability of the one-way single-wire power transfer method proposed in this study were proved by the experimental results.

Study of Constant Current-Constant Voltage Output Wireless Charging System Based on Compound Topologies

Tan, Linlin,Pan, Shulei,Xu, Changfu,Yan, Changxin,Liu, Han,Huang, Xueliang The Korean Institute of Power Electronics 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.4

Wireless power transfer (WPT) technology has the advantages of intelligence and facilitation. This paper designs a WPT system applied to battery charging and provides a strategy which switches from the constant current (CC) charging mode to constant voltage (CV) charging mode. The LCL-LCL topology is used to realize the CC output, while the LCL-S (series compensation) topology is used to realize the CV output. The main factor affecting the output characteristics is extracted by analyzing the two topologies above. Based on the main factor, this paper puts forward a modified way to design the system. In addition, on-line monitors for the battery and switches are placed at receiving side, which avoids the need for introducing an information interaction module into the system. Therefore, the complexity of the controlling system is reduced. Finally, simulation and experimental analyses are carried out to verify the correctness of the compound topologies.