Multi-mode Detection Techniques of Video Visibility Based on Improved Dual Differential Luminance Algorithm

Zhao Jiandong,Han Mingmin,Xin Xin,Li Changcheng 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.1

The traditional dual differential luminance algorithm was influenced by the surrounding environment, and was not applicable to accurate detection at night. In view of the interference factors of reality, this paper improved the dual differential luminance algorithm by using the method of amending coefficient. Meanwhile, combined with the traffic emergency control measures under different visibility, ten detection modes were subdivided. The next, an experimental system was built in the Meteorological Observatory of Beijing, and the detection software was developed. At last, the experimental data was compared with the correlation values of scatterometer. The results show that the detection accuracies are raised, and the optimized algorithm and system can be used for highway network visibility detection.

Dynamic Visual Performance of LED with Different Color Temperature

Zhao Jiandong,Ma Shuo 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.6

In order to research the dynamic visual performance of LED in mesopic vision conditions, based on the visual performance method, the software systems were developed to set different test parameters. And the hardware systems were used to collect the reaction time of testers. Color temperature of LED, ambient luminance, luminance contrast and target speed were selected as the experimental variables, and each variable had three variances. 60 sets of experiments were carried out by 20 testers. The experiment results show that reaction time of high color temperature LED is shorter than the other two. And reaction time decreases with the increasing of the ambient luminance and luminance contrast. And target speed has significant influence on visual performance in the speed range of 60km/h to 80km/h.

Sliding Mode Control for Robust Consensus of General Linear Uncertain Multi-agent Systems

Ni Zhao,Jiandong Zhu 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.8

This paper investigates the robust consensus problem for general high-order linear multi-agent systemswith external disturbances and internal uncertainties in coefficient matrices. Distributed protocols based on slidingmode control are proposed to realize the robust consensus under matched uncertainties.

Discrete Terminal Integral Sliding-Mode Backstepping Speed Control of SMPMSM Drives Based on Ultra-Local Mode

Huang Jiandong,Li Hongmei,Yang Liguo,Zhao Haonan,Zhang Peng 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.4

In this paper, a novel discrete terminal integral sliding-mode backstepping control (DTISM-BSC) is proposed for the surface-mounted permanent magnet synchronous motor (SMPMSM) drive system, which improves the speed tracking performance and robustness of the system. In this control scheme, the discrete ultra-local model (ULM) of the SMPMSM drives, which employs the algebraic parameter identification technology to handle the unknown disturbance and parametric uncertainties, is first set up. Then, the terminal integral sliding-mode surface is proposed for its advantages of finite-time convergence to achieve speed rapid tracking, in which the control performance of backstepping control is improved. Thirdly, the equivalent control law is combined with the designed switching law to construct the speed controller based on the ULM. In this case, the bounded function is adopted to improve chattering problem. Meanwhile, the asymptotic stability and rapid convergence is verified. Finally, the experimental comparisons between the proposed method and the non-singular terminal sliding mode backstepping control (NTSM-BSC) are developed to validate the effectiveness of the proposed DTISM-BSC.

Fabrication of Multifunctional PA6 Composite Fibers Based on a Synergistic Effect of Ionic Liquid Modified Carbon Nanofillers

Yonghuan Zhao,Yang Meng,Jiandong Lou,Juanjuan Su,Jian Han 한국섬유공학회 2023 Fibers and polymers Vol.24 No.10

The development of multifunctional and high-performance fibers has received much attention owing to a broad application prospect. In this work, the synergistic effect of ionic liquid modification on dispersion of graphene and carbon nanotubes in polyamide 6(PA6) was studied, and the composite fiber was prepared using melt spinning after a simple pre-solution blending. Imidazole chloride ionic liquid is adsorbed on the surface of the two carbon nanofillers through non-covalent bond, which gives a good dispersion and interface bonding in PA6 matrix. When the mass ratio of functionalized carbon nanofillers is 1:2, the mechanical properties and thermal stability of PA6 composite fiber are significantly improved compared with the pure PA6 fiber. Moreover, the PA6 composite fiber has a UV protection factor (UPF) of 158.2 and good antistatic performance with a surface resistivity of 2.60 × 107 Ω.cm. In addition, there is an excellent photothermal conversion performance from the results of 200 W infrared light irradiation test and outdoor photothermal experiments. This work provides a new idea to prepare multifunctional and high-performance composite fibers.

Preparation and Properties of Halogen-Free Flame Retardant and High Refractive Index Optical Resin via Click Chemistry

Chaoyun Luo,Jiandong Zuo,Fuquan Wang,Yanchao Yuan,Feng Lin,Jianqing Zhao 한국고분자학회 2018 Macromolecular Research Vol.26 No.4

Halogen-free flame retardant tri(acryloyloxyethyl) phosphate (TAEP) optical resin was prepared using hydroxy ethyl acrylate (HEA) and phosphorus oxychloride and the chemical structure was characterized by Fourier transform infrared spectrometer and proton nuclear magnetic resonance spectrometer. Optical resins mixed by pentaerythritol tetrathioglycolic and TAEP with different S and P contents were obtained via click chemistry curing. The curing performance, thermal stability and flame retardant performance of the optical resins were analyzed by differential scanning calorimeter, thermogravimetric analyzer, and vertical burning tester, respectively. Additionally, the burned residual morphology of samples was investigated by scanning electronic microscopy, and the refractive indices of the optical resins were measured by an Abbe refractometer. The results revealed that increasing S content could improve the refractive indices of the resins; whereas, the flame retardant performances decreased. The optical resins with S content of 2% and P contents of 7.37% had refractive indices of 1.4935 and UL 94 V-0 flame retard level, respectively. The optical resins had good thermal stability and the 5% decomposition temperature reached up to 200.1 ℃.

Elimination of the State-of-Charge Errors for Distributed Battery Energy Storage Devices in Islanded Droop-controlled Microgrids

Wang, Weixin,Wu, Fengjiang,Zhao, Ke,Sun, Li,Duan, Jiandong,Sun, Dongyang The Korean Institute of Power Electronics 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.4

Battery energy storage devices (ESDs) have become more and more commonplace to maintain the stability of islanded power systems. Considering the limitation in inverter capacity and the requirement of flexibility in the ESD, the droop control was implemented in paralleled ESDs for higher capacity and autonomous operation. Under the conventional droop control, state-of-charge (SoC) errors between paralleled ESDs is inevitable in the discharging operation. Thus, some ESDs cease operation earlier than expected. This paper proposes an adaptive accelerating parameter to improve the performance of the SoC error eliminating droop controller under the constraints of a microgrid. The SoC of a battery ESD is employed in the active power droop coefficient, which could eliminate the SoC error during the discharging process. In addition, to expedite the process of SoC error elimination, an adaptive accelerating parameter is dedicated to weaken the adverse effect of the constraints due to the requirement of the system running. Moreover, the stability and feasibility of the proposed control strategy are confirmed by small-signal analysis. The effectiveness of the control scheme is validated by simulation and experiment results.

Elimination of the State-of-Charge Errors for Distributed Battery Energy Storage Devices in Islanded Droop-controlled Microgrids

Weixin Wang,Fengjiang Wu,Ke Zhao,Li Sun,Jiandong Duan,Dongyang Sun 전력전자학회 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.4

Battery energy storage devices (ESDs) have become more and more commonplace to maintain the stability of islanded power systems. Considering the limitation in inverter capacity and the requirement of flexibility in the ESD, the droop control was implemented in paralleled ESDs for higher capacity and autonomous operation. Under the conventional droop control, state-of-charge (SoC) errors between paralleled ESDs is inevitable in the discharging operation. Thus, some ESDs cease operation earlier than expected. This paper proposes an adaptive accelerating parameter to improve the performance of the SoC error eliminating droop controller under the constraints of a microgrid. The SoC of a battery ESD is employed in the active power droop coefficient, which could eliminate the SoC error during the discharging process. In addition, to expedite the process of SoC error elimination, an adaptive accelerating parameter is dedicated to weaken the adverse effect of the constraints due to the requirement of the system running. Moreover, the stability and feasibility of the proposed control strategy are confirmed by small-signal analysis. The effectiveness of the control scheme is validated by simulation and experiment results.

Adaptive Label Propagation Algorithm to Detect Overlapping Community in Complex Networks

Chunying Li,Yonghang Huang,Zhikang Tang,Yong Tang,Jiandong Zhao 보안공학연구지원센터 2016 International Journal of Future Generation Communi Vol.9 No.8

According to the defects that community detection algorithm in unknown complex networks has a pre-parameter. We propose Adaptive Label Propagation Algorithm (ALPA) to detect community structures in complex networks. The ALPA algorithm find out all disjoint Maximal Clique (MC) and let each MC share the identical weight and unique label so as to reduce the redundant labels and uncontrollable factors. The stability of ALPA algorithm is enhanced by synchronous update during iterations. Meanwhile it will converge easily due to the termination condition that all of the vertexes have the label. During iterations we use the adaptive threshold method to overcome the pre-parameter limitation. Compared with other community detection algorithms in synthetic networks and real networks, our experiments show that ALPA algorithm not only improves the tolerance of mixing parameter, but also enhances its robustness.