Optimization of Emergency Braking Pedestrian Collision Avoidance for Autonomous Vehicle Fusing the Fuzzy Neural Network with the Genetic Algorithm

Wei Yang,Zhen Zhang,Kongming Jiang,Qian Lei,Ketong Zong 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.7

In order to improve braking performance of the intelligent vehicle, a pedestrian collision avoidance control model for autonomous emergency braking pedestrian (AEB-P) system based on the fuzzy neural network (FNN) and genetic algorithm (GA) theory is proposed. In this research, we construct a backpropagation (BP) feedforward FNN-GA model for the AEB-P system. Aiming to solve the problem that initial training parameters of the FNN model generate randomly, they are optimized by fusing the fuzzy neural network with GA. Simulation results show that training epochs reduce from 800 to 60 and training error changes from [−0.06, +0.06] to [−0.04, +0.04] after optimization. Moreover, the maximum model error lessens from 0.058 to 0.0351 and sample total error decreases from 0.0179 to 0.0068. At last, the proposed scheme is applied to the China New Car Assessment Program (C-NCAP) simulation test scenarios. Output curves of vehicle distance, velocity, and deceleration become smoother and the maximum error decreases from 0.51 m/s2 to 0.26 m/s2 , which verifies the proposed FNN-GA control strategy for AEB-P system is effective and reliable.

Computation and Analysis of Electric Field Distribution Under Lightning Impulse Voltage for 1000‑kV Gas‑Insulated‑Switchgear Spacer

Wei Yang,Taiyun Zhu,Yu Tian,Shenglong Zhu,Xi Yang 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.4

The electric feld distribution is critical to the insulation structure design of 1000-kV gas-insulated-switchgear (GIS) equipment. At present, it is not difcult to obtain the electric feld distribution under commercial frequency sinusoidal voltage; however, for lightning impulse voltage, the electric feld distribution is commonly substituted by electrostatic analysis under the peak voltage. As a result, this treatment may not embody the characteristics of the dielectric constant changing with frequency. In this paper, a frequency-domain mathematical model for transient analysis is established. The measured broadband frequency dielectric spectrum for the medium of a GIS spacer is well ftted by a H–N function model with three relaxation peaks. The transient analysis for a 1000-kV GIS spacer is realized by superposing the responses to the sinusoidal and direct current components of the lightning impulse waveform. The potential and electric feld regulation for a 1000-kV GIS spacer under lightning impulse voltage is presented and analyzed. Furthermore, the computed results from traditional electrostatic analysis are introduced for comparison. The results indicate that the electrostatic analysis increases the computed electric feld strength at the surface of the GIS spacer, while it decreases that at the interface between the GIS spacer and center conductor. It could provide computational support for the insulation structure design of 1000-kV GIS spacers.

Longitudinal static stability requirements for wing in ground effect vehicle

Wei Yang,Zhigang Yang,Maurizio Collu 대한조선학회 2015 International Journal of Naval Architecture and Oc Vol.7 No.2

The issue of the longitudinal stability of a WIG vehicle has been a very critical design factor since the first experimental WIG vehicle has been built. A series of studies had been performed and focused on the longitudinal stability analysis. However, most studies focused on the longitudinal stability of WIG vehicle in cruise phase, and less is available on the longitudinal static stability requirement of WIG vehicle when hydrodynamics are considered: WIG vehicle usually take off from water. The present work focuses on stability requirement for longitudinal motion from taking off to landing. The model of dynamics for a WIG vehicle was developed taking into account the aerodynamic, hydrostatic and hydrodynamic forces, and then was analyzed. Following with the longitudinal static stability analysis, effect of hydrofoil was discussed. Locations of CG, aerodynamic center in pitch, aerodynamic center in height and hydrodynamic center in heave were illustrated for a stabilized WIG vehicle. The present work will further improve the longitudinal static stability theory for WIG vehicle.

Spectrum Usage Forecasting Model for Cognitive Radio Networks

( Wei Yang ),( Xiaojun Jing ),( Hai Huang ) 한국인터넷정보학회 2018 KSII Transactions on Internet and Information Syst Vol.12 No.4

Spectrum reuse has attracted much concern of researchers and scientists, however, the dynamic spectrum access is challenging, since an individual secondary user usually just has limited sensing abilities. One key insight is that spectrum usage forecasting among secondary users, this inspiration enables users to obtain more informed spectrum opportunities. Therefore, spectrum usage forecasting is vital to cognitive radio networks (CRNs). With this insight, a spectrum usage forecasting model for the occurrence of primary users prediction is derived in this paper. The proposed model is based on auto regressive enhanced primary user emergence reasoning (AR-PUER), which combines linear prediction and primary user emergence reasoning. Historical samples are selected to train the spectrum usage forecasting model in order to capture the current distinction pattern of primary users. The proposed scheme does not require the knowledge of signal or of noise power. To verify the performance of proposed spectrum usage forecasting model, we apply it to the data during the past two months, and then compare it with some other sensing techniques. The simulation results demonstrate that the spectrum usage forecasting model is effective and generates the most accurate prediction of primary users occasion in several cases.

An Efficient Markov Chain Based Channel Model for 6G Enabled Massive Internet of Things

( Wei Yang ),( Xiaojun Jing ),( Hai Huang ),( Chunsheng Zhu ),( Qiaojie Jiang ),( Dongliang Xie ) 한국인터넷정보학회 2021 KSII Transactions on Internet and Information Syst Vol.15 No.11

Accelerated by the Internet of Things (IoT), the need for further technical innovations and developments within wireless communications beyond the fifth generation (B5G) networks is up-and-coming in the past few years. High altitude platform station (HAPS) communication is expected to achieve such high levels that, with high data transfer rates and low latency, millions of devices and applications can work seamlessly. The HAPS has emerged as an indispensable component of next-generations of wireless networks, which will therefore play an important role in promoting massive IoT interconnectivity with 6G. The performance of communication and key technology mainly depend on the characteristic of channel, thus we propose an efficient Markov chain based channel model, then analyze the HAPS communication system's uplink capability and swing effect through experiments. According to the simulation results, the efficacy of the proposed scheme is proven to meet the requirements of ubiquitous connectivity in future IoT enabled by 6G.

Thermally induced crystallization kinetics of uncrosslinked and unfilled synthetic cis-1,4-polyisoprene rubber monitored by shear rheological tests

Wei Yang,홍대선,김형수,김병수,Wenji V. Chang 한국유변학회 2016 Korea-Australia rheology journal Vol.28 No.4

This study demonstrates the unique capability of a shear rotational rheometer for studying the thermally induced crystallization (TIC) of uncrosslinked and unfilled cis-1,4-polyisoprene rubber (IR). At temperatures below −15℃ , a crystallization phenomenon (TIC) occurred in a quasi-unstrained IR specimen. Such a distinguished phenomenon was determined from the steady and sharp changes of both tanδ and the modulus. The changing ratio of those parameters with time characterizes the crystallization rate, on which the effects of the compressive force magnitude, testing repeat, and temperature are studied. The crystallization rate was shown to depend less on the magnitude of normal force, but depended largely on the specimen’s previous testing history. A specimen not fully recovered from the previous crystallized memory showed a faster rate than before. More cooling to −25℃ increased the crystallization rate, but the slow crystallization helped increase the final crystallinity. The crystallization rate was further interpreted by the Avrami equation to propose the crystal structure, whose morphological feature was shown in agreement with the reported TEM and X-ray results. However, our study found a thermo-mechanically aged specimen showed a very different rheological behavior at the late stage of crystallization suggesting the crystalline metamorphosis. But this unexpected behavior turned out to be unrecoverable indicating a property failure due to material aging more plausibly. All these findings were successfully monitored by the rheometer. It is expected the well-organized rheometric measurements can sufficiently supplement some instrumental limitations of the traditional crystallization monitoring analyzers on soft materials.

Fitness Game Based on Internet of Things

Wei Yang,Joonki Paik 중앙대학교 영상콘텐츠융합연구소 2020 TechArt :Journal of Arts and Imaging Science Vol.7 No.1

A New Control Strategy for Input Voltage Sharing in Input Series Output Independent Modular DC-DC Converters

Wei Yang,Zhijie Zhang,Shiyan Yang 전력전자학회 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.3

Input series output independent (ISOI) dc-dc converter systems are suitable for high voltage input and multiple output applications with low voltage rating switches. This paper proposes a novel control strategy consisting of one output voltage regulating (OVR) control loop and n-1 (n is the number of modules in the ISOI system) input voltage sharing (IVS) control loops. An ISOI system with the proposed control strategy can be applied to applications where the output loads of each module are the same. Under these conditions, IVS can be achieved and output voltages copying can be realized in an ISOI system. In this control strategy there is only one controller for each module and the design process of the control loops is simple. Since no central controller is needed in the system, modularity of the system is improved. The operation principle of the new control strategy is introduced and the control effect is simulated. Then the output power and voltage characteristics of an ISOI system under this new control strategy are analyzed. The stability of the proposed control strategy is explored base on a Hurwitz criterion, and the design guide line of the control strategy is given. A two module ISOI system prototype is fabricated and tested in the laboratory. Experimental results verify the effectiveness of the proposed control strategy.

β2-Adrenoceptor Blockade Deteriorates Systemic Anaphylaxis by Enhancing Hyperpermeability in Anesthetized Mice

Wei Yang,Toshishige Shibamoto,Yuhichi Kuda,Tao Zhang,Mamoru Tanida,Yasutaka Kurata 대한천식알레르기학회 2018 Allergy, Asthma & Immunology Research Vol.10 No.1

Purpose: Patients treated with propranolol, a nonselective β-adrenoceptor antagonist, develop severe anaphylaxis, but the mechanism remains unknown. We determined effects of β1- and β2-adrenoceptor antagonists on the anaphylaxis-induced increase in vascular permeability in mice. Methods: In anesthetized ovalbumin-sensitized C57BL mice, mean arterial blood pressure (MBP) was measured, and Evans blue dye extravasation and hematocrit (Hct) were assessed at 20 minutes after antigen injection. The following pretreatment groups (n=7/group) were studied: (1) sensitized control (non-pretreatment), (2) propranolol, (3) the selective β2-adrenoceptor antagonist ICI 118,551, (4) the selective β1-adrenoceptor antagonist atenolol, (5) adrenalectomy, (6) the selective β2-adrenoceptor agonist terbutaline, and (7) non-sensitized groups. Results: The antigen injection decreased MBP, and increased Hct and vascular permeability in the kidney, lung, mesentery, and intestine, but not in the liver or spleen. Pretreatment with ICI 118,551, propranolol and adrenalectomy, but not atenolol, reduced the survival rate and augmented the increases in Hct and vascular permeability in the kidney, intestine, and lung as compared with the sensitized control group. Pretreatment with terbutaline abolished the antigen-induced alterations. Plasma epinephrine levels were increased significantly in the sensitize control mice. Conclusions: Blockade of β2-adrenoceptor can deteriorate systemic anaphylaxis by augmenting hyperpermeability-induced increase in plasma extravasation by inhibiting beneficial effects of epinephrine released from the adrenal glands in anesthetized mice.

Terbium Tetra-Sulfosalicylate Complex as Quantitative Luminescent Sensing of Chromate Ions with High Selectivity and Sensitivity

Wei Yang,Jinfeng Xia,Guohong Zhou,Tianxi Hu,Danwang Ye,Danyu Jiang,Qiang Li 대한화학회 2019 Bulletin of the Korean Chemical Society Vol.40 No.5

In this study, a terbium(?) complex, Tb(SSA)4 (SSA?=?sulfosalicylate), was synthesized and employed to detect toxic chromate anion (CrO42?) as a visually identifiable probe. Luminescence investigations confirmed that the Tb complex is an excellent probe with high selectivity, high sensitivity (I0/I100 ?M = 9.5), and a low detection limit (2.8???10?8 M), targeting CrO42? in aqueous solution. The simple fluorescence-based probe can be quickly and easily prepared, and enables the reliable, visual detection of CrO42? ion in daily applications.