Simultaneous Optimization of Passive Transit Priority Signals and Lane Allocation

Weiguo Shi,Chunhui Yu,Wanjing Ma,Ling Wang,Lei Nie 대한토목학회 2020 KSCE JOURNAL OF CIVIL ENGINEERING Vol.24 No.2

This paper presents an integrated optimization model for the concurrent design of passive bus priority signal settings and lane allocation including lane markings for general traffic and exclusive bus lanes at isolated intersections. Traditional passive transit signal priority (TSP) strategies considered both lane markings for general traffic and exclusive bus lane settings as exogenous inputs. However, in our method, two modes of transportation (passenger cars and buses) have been considered in a centralized framework while exclusive bus lane settings, lane markings, and the optimal passive transit priority signal settings can be optimized concurrently. Minimization of the weighted delay of buses and cars is adopted as the aim of the integrated optimization model. Based on traditional National Electrical Manufacturers Association (NEMA) phase constructure, a precedence graph was employed, by which the mathematical optimization model is formulated. A set of restrictions have been set up to verify efficiency and safety for the resulting optimal lane markings and signal settings. A simulated annealing (SA) algorithm is designed to resolve the mix-integer-nonlinear-programming (MINLP) problem. In order to demonstrate the efficacy of the method proposed, numerical examples have been provided. The results from sensitivity analysis show that the proposed method can generate sub-optimal solutions for the intersection of different combinations of car demand, bus demand, and left turn ratios.

Low Carbon Concrete Prepared with Scattering-Filling Coarse Aggregate Process

Weiguo Shen,Chuan Zhang,Xinling Li,Hua Shi,Guiming Wang,Xiaowu Tian 한국콘크리트학회 2014 International Journal of Concrete Structures and M Vol.8 No.4

The volume fraction of the coarse aggregate in the conventional plastic concrete is controlled relatively low to ensure a required workability. In this paper, a new type of coarse aggregate interlocking concrete with strength ranging from C30 to C80 was prepared with scattering-filling aggregate process. The strength of concrete prepared with this method increases obviously whereas the shrinkage decreases significantly, the cement dosage in the concrete decreased 20 % at the same time. The microhardness of the ITZ between the cement paste and scattering-filling aggregate is higher than that of the original aggregate, the ITZ become narrower and tighter also. The interlocking and more even distribution of the coarse aggregate and the water absorption of the addition of extra amount of coarse aggregates contribute to the strength and performance improvement of the concrete prepared with scattering-filling aggregate process.

Nano-structured and architecturally engineered thin films and optical surfaces

Weiguo LIU,Shaobo GE,Zhili CHEN,Bing SHI 한국진공학회 2016 한국진공학회 학술발표회초록집 Vol.2016 No.8

Multivariate statistical study on naturally occurring radioactive materials and radiation hazards in lakes around a Chinese petroleum industrial area

Shi Yan,Zhao Junfeng,Ding Baiyao,Zhang Yue,Li Zhigang,M.M.Ali Mohsen,Siqin Tuya,Zhao Hongtao,Liu Yongjun,Jiang Weiguo,Wu Peng 한국원자력학회 2024 Nuclear Engineering and Technology Vol.56 No.6

The high-purity germanium gamma-ray spectrometer was used to measure the radioisotope in surface water of lakes in a Chinee petroleum industrial area. 92 samples were collected from surface water of three lakes. Activity concentrations of 232Th, 226Ra and 40K in three lakes were measured, distributed in the range of 101.8–209.4, 192.1–224.9 and 335.0–548.9 mBq/L, respectively. Results were all within the limits of WHO and China. Potential environmental and health risks were assessed by calculating some radiation hazard indicators, radium equivalent index, annual effective dose, excess lifetime cancer risk, absorbed dose rate, external hazard index, internal hazard index, annual gonadal dose equivalent, activity utilization index and representative gamma index, which ranged 0.38–0.54 Bq/L, 0.06–0.08 mSv/y, 0.23 × 10 3-0.31 × 10 3, 0.17–0.24 nGy/h, 1.01 × 10 3-1.46 × 10 3, 1.55 × 10 3-2.02 × 10 3, 1.16–1.66 μSv/y, 3.13 × 10 3-4.45 × 10 3 and 2.60 × 10 3-3.77 × 10 3. The results were all at acceptable levels, meaning no impact on human health. The relationship between the electrical conductivity of surface water and the activity concentration of 232Th, 226Ra and 40K was evaluated. The electrical conductivity value was 0.241–0.369 mS/cm, showing a significant correlation coefficient between 226Ra and 40K and electrical conductivity. Multivariate statistical methods were used to determine the relationship between the activity concentrations of 232Th, 226Ra, and 40K, radiation hazard indicators and electrical conductivity.

Performance study on the whole vibration process of a museum induced by metro

Weiguo Yang,Meng Wang,Jianquan Shi,Jiaqi Ge,Nan Zhang,Botao Ma 국제구조공학회 2015 Structural Engineering and Mechanics, An Int'l Jou Vol.55 No.2

The vibrations caused by metro operation propagate through surrounding soil, further induce secondary vibrations of the nearby underground structures and adjacent buildings. In order to investigate the effects of vibrations caused by metro on use performance of buildings, vibration experiment of Chengdu museum was carried out firstly. Then, the coupling tunnel-soil-structure finite element model was established with software ANSYS detailedly, providing a useful tool for investigating the vibration performances of structures. Furthermore, the dynamic responses and vibration predictions of museum building were obtained respectively by the whole process time-domain analysis and frequency-domain analysis, which were compared with the vibration reference values of museum. Quantitative analyses of the museum building performance were carried out, and the possible tendency and changing laws of vibration level with floors were proposed. Finally, the related vibration isolation measures were compared and discussed. The tests and analysis results show that: The vertical vibration responses almost increased with the increasing of building floors, while weak floors existed for the curve of horizontal vibration; The vertical vibrations were larger than the horizontal vibrations, indicating the vibration performances of building caused by metro were characterized with vertical vibrations; The frequencies of the museum corresponding to the peak vibration levels were around 6~17Hz; The damping effect of structure with 33m-span cantilever on vertical vibration was obvious, however, the damping effect of structure with foundation vibration isolators was not obvious.

An adaptive hybrid atom search optimization with particle swarm optimization and its application to optimal no-load PID design of hydro-turbine governor

Zhao Weiguo,Shi Tiancong,Wang Liying,Cao Qingjiao,Zhang Hongfei 한국CDE학회 2021 Journal of computational design and engineering Vol.8 No.5

One metaheuristic algorithm recently introduced is atom search optimization (ASO), inspired by the physical movement of atoms based on the molecular dynamics in nature. ASO displays a unique search ability by employing the interaction force from the potential energy and the constraint force. Despite some successful applications, it still suffers from a local optima stagnation and a low search efficiency. To alleviate these disadvantages, a new adaptive hybridized optimizer named AASOPSO is proposed. In this study, the individual and group cognitive components in particle swarm optimization (PSO) are integrated into ASO to accelerate the exploitation phase, and the acceleration coefficients are introduced to adaptively achieve a good balance between exploration and exploitation. Meanwhile, to improve the search performance of the algorithm, each individual atom possesses its own force constant, which is effectively and adaptively adjusted based on the feedback of the fitness of the atom in some sequential steps. The performance of AASOPSO is evaluated on two sets of benchmark functions compared to the other population-based optimizers to show its effectiveness. Additionally, AASOPSO is applied to the optimal no-load PID design of the hydro-turbine governor. The simulation results reveal that AASOPSO is more successful than its competitors in searching the global optimal PID parameters.

An Optimized Multi-load Wireless Power Transfer System with Constant Load Currents

Zhe Zhou,Weiguo Li,Chenwen Cheng,Zhanfeng Deng,Fangyi Li,Qiuyu Shi,Chris Mi 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

This paper proposes a multi-load wireless power transfer (WPT) system using repeater coils. The repeater unit that contains two repeater units is designed. The series-parallel-series (SPS) compensation method is used for each repeater unit. The constant load current for all the loads can be obtained with suitable resonant condition when neglecting the coils’ parasitic resistances. A feasible coil structure is designed where the two repeater coils in the same repeater unit are both bipolar that are placed perpendicularly so that the coupling between them can be neglected. A ferrite plate is inserted between the two bipolar coils in each repeater unit to enhance the magnetic coupling between adjacent units. Moreover, the proposed system has been optimized so that the system efficiency can be improved. The simulation results are given to validate the effectiveness of the proposed WPT system.

Maneuverable Aircraft Flight Control Using Nonlinear Dynamic Inversion

Qianlei Jia,Weiguo Zhang,Jingping Shi,Jiayue Hu 제어로봇시스템학회 2018 제어로봇시스템학회 국제학술대회 논문집 Vol.2018 No.10

Feedback linearization is a mature and highly applied control method in aerospace and other industrial applications. The designed control inputs are used to cancel the nonlinear terms using negative feedback of these terms. This paper focuses on designing a fight simulation model for F-16 fighter jet in responding to diverse sharp maneuvers. F-16 model is expressed by fixed-mass rigid-body six-degree-of freedom (6-DOF) equations of motion, which include the detailed aerodynamic coefficients, the engine model and the actuator models that have lags and limits. The two-time scaled concept of dynamic inversion method divides the aircraft states into groups according to their rate of response. Dynamic Inversion (DI) control law is designed for the fast variables using the aerodynamic control surfaces as inputs. Next, DI is applied to the control of the slow states using the outputs of the fast loop as inputs. Simulation results for the nonlinear flight control system have proved the validity and rationality of the proposed technique .

Tracking Strategy of Unmanned Aerial Vehicle for Tracking Moving Target

Chuanjian Lin,Weiguo Zhang,Jingping Shi 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.6

Unmanned aerial vehicles (UAVs) are prone to losing their targets when tracking moving objectives. A tracking strategy is proposed herein that enables the standoff tracking of a moving target using a vision system, which significantly reduces the occurrence of target loss. The strategy combines the Gimbal Control Algorithm based on Motion Compensation (GCAMC) with the Improved Reference Point Guidance Method (IRPGM). The GCAMC utilizes the attitude of the UAV and the deviation of the target from image center as the feedback. The target can be kept within the field-of-view (FOV) of the camera when the gimbal model is unknown. The IRPGM generates straight or circular paths according to the speed and potition of the target, while the UAV will continuously track the generated trajectory to achieve the objective of target tracking. To validate and demonstrate the tracking performance of the proposed strategy, a closed-loop visual simulation platform was devised and implemented to simulate the process of target tracking. The results of the simulation demonstrate that by using the proposed approach, the UAV can enter the desired trajectory quickly when its initial position and flight direction are arbitrary.

An Improved Method of Control Law Design at High Angle of Attack Based on Wind Tunnel Test Data

Yongxi Lyu,Yuyan Cao,Weiguo Zhang,Jingping Shi,Xiaobo Qu 제어로봇시스템학회 2018 제어로봇시스템학회 국제학술대회 논문집 Vol.2018 No.10

This paper presents an improved dynamic inversion (DI) based method, which is further successfully applied to the high angle of attack flight control of the aircraft under the influence of unsteady aerodynamics. On the basis of large oscillation wind tunnel test data, the accurate unsteady aerodynamic model is established by the sequential minimal optimization - support vector regression (SMO-SVR) method. The nonlinear longitudinal aircraft model is created by considering engine model, atmospheric model, actuator model, and so on. In order to solve the problem of large control error and control delay caused by the unsteady aerodynamics, the improved DI method is proposed. The integral is added in the pitch angle rate control, and the control law of angle of attack is designed combining lag correction. The daisy chain allocation method is utilized to obtain the deflections of the control surfaces and the engine vector nozzle. Numerical simulation of Cobra maneuver is employed to demonstrate the advantages and potential practical application of the proposed improved control law design method.