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    Review on smart highways critical technology
    Jianqing WU,Xiuguang SONG
    Journal of Shandong University(Engineering Science)    2020, 50 (4): 52-69.   DOI: 10.6040/j.issn.1672-3961.0.2020.149
    Abstract1170)   HTML484)    PDF(pc) (2579KB)(1076)       Save

    Giving highway engineering "wisdom" and establishing new generation five-in-one system of "Internet+" design, construction, management, monitoring and operation, namely, the smart highway, was the hot issue of the interdisciplinary study of civil engineering, control engineering, mechanical engineering, transportation engineering, and computer science. To comprehensively understand the smart highway, this review focused on the critical technology in the integrated system in full life-cycle of the smart highway as well as systematically investigated the relevant previous efforts, critical common technologies, and future scopes on multi-function pavement material, smart construction, smart detection, autonomous vehicles, connected vehicles, and internet of things technology.

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    Unmanned vehicle path planning based on deep Q learning in real environment
    Hao XIAO,Zhuhua LIAO,Yizhi LIU,Silin LIU,Jianxun LIU
    Journal of Shandong University(Engineering Science)    2021, 51 (1): 100-107.   DOI: 10.6040/j.issn.1672-3961.0.2020.247
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    It was an important problem for the intelligent navigation of unmanned vehicles that planning the optimal path in the actual traffic environment. At present, many researches about global path planning of unmanned vehicle mainly focused on the improvement of algorithm solution speed in the simulation environment. Most of them just only considered the optimal path distance or the current road conditions, also ignored other factors and future changes in the actual environment. In order to complete the complex task that competing global path planning of unmanned vehicle in dynamic road network, this research put forward a framework of unmanned vehicle driving system for practical environment based on the thought of planning after prediction, and put forward DP-DQN which was a fast global path planning method combined with deep Q learning and deep prediction network technology. This method used the road characteristic data such as time and space, weather et al to predict the future traffic situation, and then competed the global optimal path. Finally, experimental results based on open datasets showed that the proposed method reduced driving time 17.97% at most than Dijkstra, A*, algorithm et al.

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    The influence of shape parameters of wave energy device floating body on energy capture characteristics
    Yanjun LIU,Wei WANG,Zhi CHEN,Donghai WANG,Dengshuai WANG,Gang XUE
    Journal of Shandong University(Engineering Science)    2020, 50 (6): 1-8,16.   DOI: 10.6040/j.issn.1672-3961.0.2020.160
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    To clarify the effect of the floating body′s shape parameters on the energy capture performance and working stability, an oscillating float type wave energy converter (WEC) model with linear power take-off system was established. Frequency domain calculation theory was used to deduce the formulas of energy capture power and energy capture width ratio. After introducing the numerical simulation steps of floating body in frequency domain, ANSYS-AQWA software was used to investigate the floater's energy capture power and energy capture width ratio with different bottom shapes and half vertex angles. Influence of shape parameters on the energy capture performance was drawn to provide a theoretical basis for the shape optimization of the floating body applied to the wave power supply device and floating platform. The results showed that the practical fabrication feasibility of circular truncated cone bottom was higher than that of cone and sphere. The energy capture characteristics and stability of circular truncated cone bottom were better than that of general cylindrical floating body in the intermediate wave frequency band. The energy capture performance and working stability of circular truncated cone floating body with big top and small bottom were better. The energy capture performance under intermediate frequency waves could be improved with the increase of the half vertex angle. The optimal power capture performance and working stability could be achieved with a proper apex angle.

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    Visual sentiment analysis based on spatial attention mechanism and convolutional neural network
    Guoyong CAI,Xinhao HE,Yangyang CHU
    Journal of Shandong University(Engineering Science)    2020, 50 (4): 8-13.   DOI: 10.6040/j.issn.1672-3961.0.2019.422
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    Existing visual sentiment analysis based on deep learning mainly ignored the intensity differences of emotional presentation in different parts of the image. In order to solve this problem, the convolutional neural network based on spatial attention (SA-CNN) was proposed to improve the effect of visual sentiment analysis. The affective region detection neural network was designed to discover the local areas of sentiment induced in images. The spatial attention mechanism was used to assign attention weights to each location in the sentiment map, and the sentiment features of each region were extracted appropriately, which was helpful for sentiment classification by using local information. The discriminant visual features were formed by integrating local region features and global image features, and were used to train the neural network classifier of visual sentiment. Classification accuracy of the method achieved 82.56%, 80.23% and 79.17% on three real datasets Twitter Ⅰ, Twitter Ⅱ and Flickr, which proved that the method could improve the visual emotion classification effect by making good use of the difference of emotion expression in the local area of the image.

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    Research progress of ocean wave energy converters
    Yanjun LIU,Shuang WU,Dengshuai WANG,Ruohong WANG
    Journal of Shandong University(Engineering Science)    2021, 51 (5): 63-75.   DOI: 10.6040/j.issn.1672-3961.0.2021.234
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    In order to accurately keeping the developments of ocean wave energy utilization technology, the important research progress of wave energy converters was reviewed. The forms of wave energy converters had not yet converged. According to the classification principle of different energy capture methods, the working principle and the energy conversion system of three main types of devices, namely, oscillating water column, overtopping and oscillating bodies were introduced. The advantages and disadvantages of each type of converter were analyzed. Typical engineering devices were selected for detailed introduction. The engineering devices which had been completed sea trial in China were summarized. It has been found that the oscillation type was the most popular type of converter in China. The research progress related to the performance evaluation of wave energy converters were summarized, but there was no unified evaluation standard yet. The difficulties and the main breakthrough directions of the developments of wave energy converters were discussed from three aspects of high efficiency and stability, reliability and cost, and the construction of diversified integrated platforms.

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    Eye tracking in human-computer interaction control
    Hui HE,Junhao HUANG
    Journal of Shandong University(Engineering Science)    2021, 51 (2): 1-8.   DOI: 10.6040/j.issn.1672-3961.0.2020.346
    Abstract698)   HTML55)    PDF(pc) (4362KB)(273)       Save

    To actualize the simple and low-cost eye-tracking based human-computer interaction, an exact interaction method based on the visual directions estimation and eye tracking with webcam videos was proposed. A simple and fast convolution neural network model was used to roughly estimate the user′s viewpoints on the screen. And then an accurate human-computer interaction method was proposed on the basis of the eye movements recognition and sight line tracking results. To verify the effectiveness of the method, the key operations of eye mouse and eye typing were developed. The test results show that the proposed method enabled users to achieve eye tracking and to actualize most precise human-computer interactions with only one common monocular camera, which was expected to completely replace the mouse and keyboard hardwares.

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    Review on development of simultaneous localization and mapping technology
    Jianqing WU,Xiuguang SONG
    Journal of Shandong University(Engineering Science)    2021, 51 (5): 16-31.   DOI: 10.6040/j.issn.1672-3961.0.2021.168
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    As a hot spot in the field of intelligent transportation, simultaneous localization and mapping (SLAM) technology is the key to autonomous path planning for self-driving vehicles. This review focused on four parts with introduction of sensors related to SLAM technology, localization, mapping, and multi-sensor integration. Each step of realization for SLAM technology was introduced from advantages and disadvantages, range of application, probability algorithm, types of map, and integration methods. Based on the investigation of relevant researches about multi-sensor integration, common problems of SLAM technology were analyzed, future development trend and practical engineering application of SLAM technology were prospected.

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    Analysis of the influence of the underside baffle and deflector of the fume hood on the flow field
    Ruiyi YAN,Zhen DONG,Sen LU,Yanhua LAI,Mingxin LÜ
    Journal of Shandong University(Engineering Science)    2021, 51 (5): 122-130.   DOI: 10.6040/j.issn.1672-3961.0.2021.177
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    For the phenomenon of vortex and gas escape in the flow field of the extant fume hood, the computational fluid dynamics method was used for simulation. This research changed the shape parameters of the underside structure of the fume hood window, used circular arc baffles with different radii, elliptical arc baffles with different lengths, and added deflectors with different radii. Then this research studied the influence of structural changes on the flow field in the fume hood by analyzing the size and location of the vortex to obtain the direction of structural optimization. The results showed that when the height of the underside baffle was low and the length was short, there was obvious large vortex in the center position of the fume hood and near the wall. A baffle with a height greater than 50 mm and a length greater than 90 mm could significantly reduce the vortex at the center of the fume hood and at the junction of the baffle and the side wall. Adding a deflector could optimize the flow field and make the center vortex disappear, and the radius of the deflector should not be greater than 70 mm, otherwise obvious vortices would be excited on the outside and end of the baffle, which provides a basis for the rational design of fume hoods.

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    Automatic detection research of arrhythmia based on CNN-LSTM hybrid model
    TAO Liang, LIU Baoning, LIANG Wei
    Journal of Shandong University(Engineering Science)    2021, 51 (3): 30-36.   DOI: 10.6040/j.issn.1672-3961.0.2020.445
    Abstract493)      PDF(pc) (3912KB)(241)       Save
    A hybrid algorithm of convolutional neural network and long short-term memory network was proposed for automatic detection of arrhythmias. The model structure was composed of 5 convolutional layers, 5 pooled layers, 1 LSTM layer and 1 fully connected layer. By taking advantage of CNN's ability to automatically extract features and LSTM's ability to capture dependencies before and after time series, the simple preprocessed ECG signal data were directly input into the hybrid model. The whole model combined the two steps of feature extraction and classifier classification, so as to identify five different arrhythmias more efficiently and accurately. The accuracy, sensitivity and specificity of the test set were 99.48%, 99.47% and 99.86% respectively. The experimental results showed that the proposed method could efficiently and accurately identify different types of arrhythmias.
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    Research advance in the source, water pollution status and treatment processes of perchlorate
    Baoyu GAO,Wen SONG,Guangping YAO,Qinyan YUE
    Journal of Shandong University(Engineering Science)    2020, 50 (5): 107-117.   DOI: 10.6040/j.issn.1672-3961.0.2019.572
    Abstract825)   HTML330)    PDF(pc) (2943KB)(240)       Save

    Perchlorate was widely used in military manufacturing, aerospace and industrial production, which had high stability, high water solubility, strong oxidizability and low volatility. With the flow of air and water migration, increasingly serious perchlorate water pollution caused widespread concern worldwide. Therefore, many countries carried out a comprehensive research and investigation on the source, water pollution status and treatment technology of perchlorate. However, China still had a few reports on perchlorate study, seriously neglecting the situation and treatment research of perchlorate pollution and lacking relevant environmental quality standards and safety concentration limits. This paper reviewed the source, hazard and water pollution status of perchlorate, analized the existing worldwide perchlorate concentration limit standards, and summarized the research progress of perchlorate treatment process in order to provide some references for further development of perchlorate study and formulation of relevant regulations in China.

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    Overview of multi-motion vision odometer
    Fengyu ZHOU,Panlong GU,Fang WAN,Lei YIN,Jiakai HE
    Journal of Shandong University(Engineering Science)    2021, 51 (1): 1-10.   DOI: 10.6040/j.issn.1672-3961.0.2020.382
    Abstract554)   HTML395)    PDF(pc) (3543KB)(236)       Save

    Multi-motion visual odometry (MVO) was an algorithm for estimating the pose change of dynamic objects in dynamic scenes. It was of great theoretical significance and practical value in autonomous things (AuT). The development process and the latest research progress of multi-motion visual odometer in robot field were reviewed. The important research results of multi-motion visual odometer with the fusion of semantic and geometric features were introduced. Based on the same evaluation criteria and datasets, this research compared several common methods, and prospected the future development direction of multi motion visual odometer.

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    Algorithm of adaptive slope adjustment of quadruped robot based on model predictive control and its application
    LIANG Qixing, LI Bin, LI Zhi, ZHANG Hui, RONG Xuewen, FAN Yong
    Journal of Shandong University(Engineering Science)    2021, 51 (3): 37-44.   DOI: 10.6040/j.issn.1672-3961.0.2020.320
    Abstract414)      PDF(pc) (6868KB)(230)       Save
    In order to realize the adaptive and stable walking of the quadruped robot on slope terrain, the adaptive adjustment strategies of both feet position and trunk posture of quadruped robot on slope were proposed based on the model predictive control. The posture determination parameters of the robot in locomotion were measured by the inertial measurement unit(IMU). By means of the derived foot end trajectory algorithm, the coordinate mapping of its toe position was obtained in order to adjust the center of gravity of the robot on the slope. Then the adaptive adjustment of the trunk posture of the robot in the process of climbing could be achieved through the trunk posture adjustment algorithm by means of designed “virtual slope”. With the help of the physical platform of quadruped robot and the actual slope terrain environment built in the laboratory, the feasibility and validity of the proposed algorithm are verified. Experimental result showed that the proposed slope adaptive control method had improved the stability margin of the robot on the slope and optimized the foot end motion space, thus leading to the realization of adaptive adjustment in climbing slope for the quadruped robot.
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    Impact analysis of road traffic on urban air quality in congested environment
    FENG Haixia, WANG Qi, YANG Licai, KOU Junying, XIE Qingmin, ZHAO Junxue, MENG Xianglu, WANG Yanfeng
    Journal of Shandong University(Engineering Science)    2021, 51 (1): 128-134.   DOI: 10.6040/j.issn.1672-3961.0.2020.211
    Abstract794)      PDF(pc) (3465KB)(208)       Save
    Focusing on research hot issues of traffic congestion, haze(air quality), and the main urban area of Jinan taken as an example, the paper quantitatively analyzed the impact of peak congestion delay index and traffic operation index on urban air quality. Combining with satellite retrieval of aerosol optical depth(AOD ), the impact of road traffic on air quality in congestion environment was quantitatively analyzed based on geographical weighted regression model. The results showed that there was a strong correlation between the peak congestion delay index and the air quality index. The traffic operation had great influence on air quality. Geographically weighted regression(GWR)refined local spatial features. Under traffic congestion conditions, the road area occupancy rate had the greatest impact on air quality in the region. The paper had certain guiding significance for traffic planning and provided support for traffic planning and control.
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    Real-time semantic segmentation of high-resolution remote sensing image based on multi-level feature cascade
    Chunhong CAO,Hongxuan DUAN,Ling CAO,Lele ZHANG,Kai HU,Fen XIAO
    Journal of Shandong University(Engineering Science)    2021, 51 (2): 19-25.   DOI: 10.6040/j.issn.1672-3961.0.2020.225
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    Aiming at the problems of long segmentation time and inaccurate segmentation of small targets in remote sensing image semantic segmentation, a fast semantic segmentation model of high-resolution remote sensing image based on multi-level feature cascade network (MFCNet) was proposed. The model was mainly composed of feature encoding, feature fusion and target refinement. Feature encoding extracted the input images feature of different resolutions and used different backbone networks. Due to the lower resolution of low-resolution images, heavy-weight backbone networks were used to obtain rich semantic information with fewer parameters. For medium and high-resolution images, lightweight backbone network was used to reduce the amount of parameters and obtain global information. While medium and low-resolution encoding used the way of weights and calculation sharing to further reduce model parameters and computational complexity. The feature fusion section fused features from different branches to obtain information at different scales. The target refinement used residual to correction the fused features and the features of the coded part to restore the spatial detail information of the image, making the segmentation more accurate. And the entire model worked efficiently in an end-to-end manner. The experimental verified the validity of the model in semantic segmentation of remote sensing images, and achieved a good balance between model complexity and accuracy.

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    Optimal calculation method of pavement shakedown limit based on genetic algorithm
    Xiuguang SONG,Yingchao ZHANG,Peizhi ZHUANG,He YANG,Haifeng ZHANG,Juan WANG
    Journal of Shandong University(Engineering Science)    2021, 51 (5): 1-7.   DOI: 10.6040/j.issn.1672-3961.0.2021.153
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    To solve the problem that road structures are prone to elasto-plastic deformation under the action of long-term reciprocating vehicle loads, based on the static shakedown theorem, the shakedown behavior of the semi-infinite space Mohr-Coulomb structure under the Hertz load was studied, and the genetic algorithm was introduced to construct an efficient calculation method for the lower limit of the shakedown limit of the road structure under the reciprocating vehicle load. The accuracy and efficiency of the new method was verified by comparison with the existing solution method and parameter analysis.

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    Fuzzy control of structure vibration mode based on BP neural network algorithm
    Zhiwei WANG,Nan GE,Chunwei LI
    Journal of Shandong University(Engineering Science)    2020, 50 (5): 13-19.   DOI: 10.6040/j.issn.1672-3961.0.2019.509
    Abstract494)   HTML18)    PDF(pc) (2278KB)(195)       Save

    In order to control the seismic response of civil engineering structures more reasonably and conveniently, a fuzzy control algorithm based on BP neural network was proposed. The neural network was trained with the structural seismic dynamic response data to establish the structural analysis model, and the time-domain modal coordinates were taken as the controlled variables to reduce the order of the system, so that the number of fuzzy reasoning required to establish the modal fuzzy control rules was within the acceptable range, and the system energy minimum was taken as the control target to formulate the control rules. The fuzzy control numerical model of structural dynamic response was established to evaluate the damping effect of the proposed algorithm based on the calculated value of seismic dynamic response. The results showed that the trained BP neural network could accurately predict the seismic dynamic response of the structure and establish fuzzy control rules accordingly. Using mode fuzzy control only for the first mode of the structure could achieve satisfactory damping effect. When active mass driver(AMD) optimal control amplitude was used as the control domain of each floor, the damping effect of modal fuzzy control was different from it. A better damping effect could be obtained by increasing the control field.

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    An integrated learning approach for O3 mass concentration prediction model
    Yan PENG,Tingting FENG,Jie WANG
    Journal of Shandong University(Engineering Science)    2020, 50 (4): 1-7.   DOI: 10.6040/j.issn.1672-3961.0.2019.423
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    In order to accurately predict O3 mass concentration and development trend and to analyze inducing factors, an O3 mass concentration prediction model based on integrated learning was proposed. A multilayer FS-IL model for the O3 pollutant mass concentration was established in accordance with the data of O3 pollutant mass concentration and meteorological factors from 2015 to 2016 in Beijing, on the basis of missing value filling and outlier analysis, Pearson correlation analysis and Lasso regression analysis were used to select features of the cleaned meteorological data to eliminate data redundancy and improve prediction accuracy; an integrated learning algorithm based on self-organizing featuremap (SOFM)-Elman neural network (ENN) was proposed. After clustering sample data with SOFM to realize reasonable distribution of samples, ENN was used for simulation training to predict O3 mass concentration. The experimental results showed that the accuracy of ENN-based O3 pollutant mass concentration prediction was improved from 74.6% to 82.1% after the preliminary processing of data with Pearson-Lasso feature selection and SOFM sample clustering.

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    Optimization of the inner deflector of the shrimp-waist elbow
    Jinsheng QI,Hongzhen CAO,Yan SHI,Wenjing DU,Zhan WANG
    Journal of Shandong University(Engineering Science)    2020, 50 (5): 64-69, 76.   DOI: 10.6040/j.issn.1672-3961.0.2020.093
    Abstract548)   HTML15)    PDF(pc) (5415KB)(181)       Save

    In order to study the distribution of the flow field and improve the uniformity of the flow field in a shrimp-waist bend, a series of three-dimensional numerical simulation studies on the turbulent secondary flow in a bend before and after the installation of the deflector was carried out by using the Realizable k-ε model. The results showed that when the deflector was not arranged in the shrimp-waist bend pipe, a large range of low-speed zones appeared in the horizontal straight pipe section after the fluid turns, and a backflow phenomenon occured at the same time. The airflow distribution was extremely uneven and the pressure resistance was large. After the deflector was arranged, the flow characteristics of the fluid in the elbow were effectively improved and the energy loss of the system was reduced. Based on the analysis of the influence of different number, structure and arrangement of deflectors on the uniformity of flow field and pressure drop loss of the bend, the optimal arrangement of deflectors in the shrimp-waist bend was proposed as follows: the number of deflectors was 3, the deflectors′ center angle was 60°, and the deflectors were all arranged backward.

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    Photovoltaic power prediction method based on NWP irradiance inclination conversion
    Wenling JIANG,Yanqing ZHAO,Bo WANG,Shuanglei FENG,Yan PEI,Fei ZHANG
    Journal of Shandong University(Engineering Science)    2021, 51 (5): 114-121.   DOI: 10.6040/j.issn.1672-3961.0.2020.104
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    Short-term photovoltaic (PV) power predictions statistical methods generally used the horizontal irradiance in numerical weather prediction (NWP) directly, but not the inclined irradiance received by tilt PV panels, which led to the calculation results not accurate enough. This paper proposed a new method to convert horizontal irradiance to inclined one. The method distinguished scattering into molecular scattering and Mie scattering with different properties, and then converted them separately. Using the new method, the paper converted NWP horizontal irradiance to inclined one. Based on inclined one, PV power model and prediction were made. The result of an example showed that the new method, whose root mean square error was 10.25% and correlation coefficient was 0.914 0, was more accurate than the traditional method, which used NWP horizontal irradiance directly.

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    Lightweight face super-resolution network based on asymmetric U-pyramid reconstruction
    Tongyu JIANG,Fan CHEN,Hongjie HE
    Journal of Shandong University(Engineering Science)    2022, 52 (1): 1-8, 18.   DOI: 10.6040/j.issn.1672-3961.0.2021.312
    Abstract240)   HTML8)    PDF(pc) (9804KB)(174)       Save

    A lightweight face super-resolution network was proposed in order to solve the problem that the model of deep convolutional neural network was complicated and difficult to be applied in the face super-resolution task. The coder composed of rescoding blocks was used for feature extraction, and pyramid reconstruction was introduced into the decoder to achieve fast and accurate super-resolution. To reduce the parameter number of the up-sampling operation in the decoding block, a non-uniform channel widening strategy based on resolution selection was adopted. To avoid adding extra branches, the prior knowledge of the face was introduced through heatmap loss. Experimental results showed that the model proposed in this paper could achieve light and accurate super-resolution reconstruction of ultra-low resolution face images that achieved better visual quality than the state-of-the-art method with lower model complexity.

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    Adaptive sliding mode synchronization of a class of nonlinear chaotic systems
    Chunrui CHENG,Beixing MAO
    Journal of Shandong University(Engineering Science)    2020, 50 (5): 1-6.   DOI: 10.6040/j.issn.1672-3961.0.2019.573
    Abstract523)   HTML38)    PDF(pc) (441KB)(171)       Save

    The synchronization of a class of nonlinear chaotic systems with model uncertainties and external disturbances was studied based on adaptive sliding mode control. A novel nonsingular terminal sliding surface was proposed and its stability was proved. On the basis of Lyapunov stability theory, a sliding mode control law was derived to force the trajectory of the synchronization error systems onto the sliding surface and to guarantee the occurrence of the sliding motion. The proposed control scheme was applied to synchronize chaos of integer order and fractional-order nonlinear chaotic systems in the presence of both model uncertainties and external disturbances. A numerical simulation taking the fractional Victor-Carmen system as the example demonstrated the applicability and efficiency of the proposed sliding mode control technique and verified the theoretical results of the research.

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    Law of horizontal deformation displacement of tunnels due to adjacent excavation
    LI Lianxiang, ZHANG Qiang, SHI Jinjiang, LIU Jiadian, HOU Yingxue
    Journal of Shandong University(Engineering Science)    2021, 51 (1): 46-52.   DOI: 10.6040/j.issn.1672-3961.0.2020.340
    Abstract495)      PDF(pc) (1666KB)(170)       Save
    The horizontal displacement of the tunnel hance was divided into three parts. Based on the change of horizontal coefficients of subgrade reaction, the paper proposed the concept of “horizontal deformation displacement”, which was analyzed by the PLAXIS 3D. And the correlation formula between the maximum horizontal deformation displacement and the foundation pit width and the horizontal distance was obtained by fitting. The results showed that the horizontal deformation displacement decreased exponentially with the increase of the horizontal distance between the tunnel and the foundation pit, and the influence of the foundation pit width was ignored when the value of the horizontal distance was greater than the depth of the foundation pit. The formula derived in this paper could be used to calculate the horizontal convergence value of the tunnel adjacent to the excavation, the horizontal displacement of the tunnel hance, and the horizontal coefficients of subgrade reaction near the tunnel.
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    Pollution characteristics and intake risk assessment of short and medium-chain chlorinated paraffins in foods in Jinan
    Xinxin FANG,Shiwen ZHANG,Yuting ZHU,Wei JIANG,Zhaoyuan ZHANG,Nan ZHAO
    Journal of Shandong University(Engineering Science)    2021, 51 (3): 119-128.   DOI: 10.6040/j.issn.1672-3961.0.2021.001
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    To explore the distribution status and intake risk of short-chain chlorinated paraffins (C10-13, SCCPs) and medium-chain chlorinated paraffins (C14-17, MCCPs) in food in Jinan city, 82 kinds of food were collected in Jinan in 2020 and analyzed by chlorine enhanced atmospheric pressure chemical ionization source- four-stage pole time-of-flight mass spectrometry. The results showed that the concentration of wet weight of SCCPs in food samples ranged from 5.3 to 2 483.2 ng/g, MCCPs ranged from 4.6 to 605.1 ng/g. The concentration of wet weight of SCCPs in Peanut oil was the highest, which was 2 115.5 ng/g. The concentration of wet weight of SCCPs in balsam pear was the lowest, which was 5.7 ng/g. The concentration of wet weight of MCCPs in soybean oil was the highest, which was 605.5 ng/g. The concentration of wet weight of MCCPs in Chinese cabbage was the lowest, which was 6.2 ng/g. The estimated daily intake (EDI) of SCCPs was the highest in staple foods, which was 2 619.2 ng/(kg ·d) and the lowest in aquatic foods, which was 17.7 ng/(kg ·d). The EDI of MCCPs was the highest in staple foods, which was 2 117.6 ng/(kg ·d), and the lowest in aquatic foods, which was 12.1 ng/(kg ·d). The hazard quotients (HQ) of SCCPs、MCCPs was 0.041 and 0.032, respectively. The purpose of this study was to provide reference data for the assessment of the risk of exposure to CPs among the population in Jinan.

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    A scheduling algorithm based on multi-objective container cloud task
    Xiaolan XIE,Qi WANG
    Journal of Shandong University(Engineering Science)    2020, 50 (4): 14-21.   DOI: 10.6040/j.issn.1672-3961.0.2018.210
    Abstract623)   HTML97)    PDF(pc) (1365KB)(161)       Save

    In order to solve the unrealistic, unfair, inefficient and unbalanced problems caused by container cloud scheduling model facing isomorphic tasks, isomorphic resources and single objectives, a tree scheduling objective model with constraint repair was proposed. Based on heterogeneous tasks and resources, constraint repair was adopted to avoid the impracticability of mapping scheme, and then priority to synthesize multiple sub-goals and attributed them to sub-spaces under different tree branches, and eventually achieved a fair, efficient, economical and balanced scheduling model among multiple upper application frameworks. The experimental results showed that the tree scheduling objective model with constrained repair was not inferior to other single-objective models in fairness, which could meet more tasks, and had higher resource utilization and load balancing under the preceding conditions. It was superior to the single-objective model in practicability, fairness, efficiency and balancing and ensured fair allocation of resources, which increased the benefits of container services, decreased the cost of physical resources, increased the stability and availability.

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    Design pattern classification mining with feature metrics constraints
    Zhuoyu XIAO,Pei HE,Guo CHEN,Yunbiao XU,Jie GUO
    Journal of Shandong University(Engineering Science)    2020, 50 (6): 48-58.   DOI: 10.6040/j.issn.1672-3961.0.2020.229
    Abstract462)   HTML27)    PDF(pc) (1397KB)(161)       Save

    To solve low accuracy for design pattern mining, a method for design pattern classification mining with feature metrics constraints was presented. 47 feature metrics information based on structural pattern, behavioral pattern and creative pattern was classified and summarized, and definition of design pattern were given, and features of design patterns were described, three benchmark systems and four well-known system experiments for design pattern mining were designed. Experimental results show that proposed method is effective, and the accuracy of the proposed method was 96.13%, 91.67%, 72.23% for Adapter pattern. Command pattern and Factory method pattern for three benchmark systems, and the accuracy of the proposed method is 84.3%, 81.26%, 73.17% for Adapter, Command and Factory Method of design pattern for four well-known systems, compared to well-known methods by experiment of design pattern mining, indicating the effectiveness of the proposed method.

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    Electric vehicle virtual energy storage available capacity modeling
    Bei LI,Song ZHAO,Zhijia XIE,Meng NIU
    Journal of Shandong University(Engineering Science)    2020, 50 (6): 101-111.   DOI: 10.6040/j.issn.1672-3961.0.2020.128
    Abstract510)   HTML24)    PDF(pc) (2357KB)(154)       Save

    In order to efficiently implement the virtual energy storage dispatch of electric vehicles in a wide area, the article focused on the types of electric vehicles that respond to electric vehicle virtual energy storage (EVVES) services by clustering, combined with the use habits of all kinds of electric vehicle owners (such as daily driving mileage, charging and discharging rules, expected standby travel electricity, etc.), the impact of market on EVVES responsiveness, redundant design of available energy storage capacity and other factors, a virtual energy storage (VES) capacity estimation model was established. Combined with the technical requirements of power system for energy storage to participate in system services, such as emergency power support, smooth renewable energy output, UPS/EPS, etc., the matching basis of supply and demand was proposed. Based on Monte Carlo simulation method, the practicability of the model to estimate the available capacity of response VES service in different time periods was verified, which layed the foundation for the operation practice of EVVES in future.

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    Ultimate uplift capacity of shallow vertical plate anchors in sand
    Xiuguang SONG,He YANG,Xiaoyan CHEN,Wenjie CUI,Hongya YUE,Kai ZHANG,Juan TIAN
    Journal of Shandong University(Engineering Science)    2021, 51 (1): 24-31, 38.   DOI: 10.6040/j.issn.1672-3961.0.2020.265
    Abstract434)   HTML125)    PDF(pc) (5430KB)(152)       Save

    This paper investigated the pullout behaviour of shallow vertical plate anchors in sand. Pull-out model tests were performed using the particle image velocimetry (PIV) technology, by which the soil deformation and failure mechanisms were observed. Then the ultimate bearing capacity of vertical plate anchors at various soil properties and cover depths was simulated using the finite element limit analysis software. According to the observed failure mechanism, a limit equilibrium solution was developed to calculate the bearing capacity of shallow strip plate anchors in sand, which was then extended for the prediction of the ultimate bearing capacity of rectangle plate anchors by introducing a shape coefficient. Results predicted by the new limit equilibrium solution showed close agreement with those by the lower bound limit analysis solution. The limit equilibrium solution was compared with 51 experimental data, which showed an average of 5% overestimation of the ultimate bearing capacity. This research can provide a theoretical method for the calculation of the ultimate bearing capacity of shallow plate anchors in sand.

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    MIRGAN: a medical image report generation model based on GAN
    Junsan ZHANG,Qiaoqiao CHENG,Yao WAN,Jie ZHU,Shidong ZHANG
    Journal of Shandong University(Engineering Science)    2021, 51 (2): 9-18.   DOI: 10.6040/j.issn.1672-3961.0.2020.227
    Abstract498)   HTML44)    PDF(pc) (2295KB)(152)       Save

    The medical image report generation task based on image understanding became a widely concerned issue. Compared with the traditional image understanding task, medical image report generation was a more challenging task. We proposed a medical image report generative adversarial network (MIRGAN) model for this task. A co-attention mechanism was adopted to synthesize the visual and semantic features of multiple feature areas and generate descriptions corresponding to these areas. Combining the generative adversarial networks (GAN) and reinforcement learning (RL) optimized the performance of the generative model to output higher quality reports. The experiment results demonstrated the effectiveness of our proposed MIRGAN model.

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    Optimization of ventilation system of TBM tunnel construction and evaluation of dust suppression effect
    WANG Chunguo
    Journal of Shandong University(Engineering Science)    2021, 51 (3): 52-60.   DOI: 10.6040/j.issn.1672-3961.0.2020.468
    Abstract376)      PDF(pc) (5863KB)(145)       Save
    Hard rock tunneling boring machine(TBM)produces a large amount of dust during construction, which is an important factor affecting the operating environment and the health of workers. To further optimize the construction ventilation and dust removal effect, combined with the actual working conditions of Qingdao Metro Line 1 double shield TBM, Ansys-Fluent software was used to carry out numerical analysis of the tunnel excavation process. The wind speed and dust mass concentration at each location of the tunnel were detected and compared with the numerical simulation results to verify the effectiveness of the model. In view of whether it is necessary to open the dust removal system in the process of TBM tunnel construction, as well as the location of dust removal tuyere and the selection of optimal suction flow, numerical simulation was carried out. When the dust removal system was turned off or the dust removal system was turned on but the suction flow was below 4 m3/s, and the dust diffuses to most areas of the TBM tunneling area. When the dust duct was 15 m away from the hand surface and the suction airflow was 12 m3/s, the dust removal effect reached the best, and the dust diffusion distance was reduced to 45 m, which could effectively remove dust. The research results could provide a scientific basis for the design and construction of tunnel ventilation and dust removal.
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    Adaptive multi-domain sentiment analysis based on knowledge distillation
    YANG Xiuyuan, PENG Tao, YANG Liang, LIN Hongfei
    Journal of Shandong University(Engineering Science)    2021, 51 (3): 15-21.   DOI: 10.6040/j.issn.1672-3961.0.2020.249
    Abstract361)      PDF(pc) (2317KB)(144)       Save
    An adaptive multi-domain knowledge distillation framework was proposed, which effectively accelerated reasoning and reduced model parameters while ensuring model performance. The knowledge distillation method was used to study sentiment analysis problems. When performing knowledge distillation for each specific field, model distillation involved word embedding layer distillation, coding layer distillation(attention distillation, hidden state distillation), output prediction layer distillation and other aspects of distillation, in order to learn all aspects knowledge from the specific field teacher model. Selectively learning the importance of the teacher model corresponding to different fields to the data was proposed, which further improved the accuracy of the prediction results. The experimental results on multiple public datasets showed that after single-domain knowledge distillation increased the model accuracy by an average of 2.39%, while multi-domain knowledge distillation increased the model accuracy by an average of 0.5%. Compared with the knowledge distillation of a single domain, this framework enhanced the generalization ability of the student model and improved the performance.
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    Optimal structure of pressure cast-situ-pile with spray-expanded frustum
    Lianxiang LI,Hongxia XING,Jinliang LI,Hengli HUANG,Lei WANG
    Journal of Shandong University(Engineering Science)    2020, 50 (6): 82-91.   DOI: 10.6040/j.issn.1672-3961.0.2020.090
    Abstract554)   HTML24)    PDF(pc) (6556KB)(140)       Save

    According to the field test results of pressure cast-situ-pile with spray-expanded frustum, with the help of Abaqus to establish the numerical model of the experiment, the influence rule of expanded body with frustum (hereinafter referred to as frustum) on surrounding soil under vertical load was obtained. It was clarified that the soil mass had squeezing effect within the 2D~3D range (D is frustum's diameter) and it reached the limit at 0.5 m under the frustum. Stress relaxation occured in the upper soil of frustum, which reached the limit value at the top of the frustum, and of which the vertical influence range was extended by 1.25D and the horizontal influence range was 1.5D~2.5D. Revealed that the optimal spray angle for frustum expanding was 50°~55°, the optimum expanding ratio was 2~2.75, the optimal position was in the D~2D range of upper part of pile, and it was optimal when the fixed spray wing was 7~8 m below the pile top. The optimal construction model could increase the bearing capacity by 19%, therefore it was suggested to adopt the optimal structural pile type to further improve efficiency and promote application of the pile.

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    Influence of TBM tunnel excavation at different positions on buildings
    SUN Jie, WU Ke, ZHENG Yang, LI Shuchen, YUAN Chao, WANG Xiuwei
    Journal of Shandong University(Engineering Science)    2021, 51 (1): 32-38.   DOI: 10.6040/j.issn.1672-3961.0.2020.331
    Abstract384)      PDF(pc) (8680KB)(136)       Save
    In view of the settlement and deformation of existing buildings induced by TBM(tunnel boring machine)tunnel excavation of urban subway, considering the complexity of the actual working conditions of tunnel undercrossing urban buildings, taking the TBM tunnel tunneling in hard rock stratum of Xiaobei Section of Qingdao Metro Line 1 as the actual engineering background, the numerical calculation method was adopted to establish the continuous tunneling of TBM tunnel through several existing buildings. Based on the engineering construction practice, the spatial attribute characteristics of TBM tunnel were systematically studied. The stress-strain state of ground layer and existing buildings induced by TBM tunnel double tunnel driving under existing buildings were studied systematically. The research results showed that the shallower the tunnel depth was, the greater the settlement rate of the buildings affected by the tunnel excavation. In the excavation of double track tunnel, the larger the proportion of buildings affected by the excavation of the tunnel with shorter transverse distance, the greater the tunnel buried depth, the greater the influence of the superposition of double tunnels. When the tunnel passed through the irregular building, it had great influence on the corner of the building and the small building near the large-scale building, so it needed to be monitored in the actual construction.
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    Modified calculation method of shaft friction for driven pile considering particle size effect
    Peizhi ZHUANG,Yingchao ZHANG,Xiuguang SONG,He YANG,Zhicheng GUO,Yan HU
    Journal of Shandong University(Engineering Science)    2021, 51 (5): 8-15.   DOI: 10.6040/j.issn.1672-3961.0.2021.161
    Abstract341)   HTML224)    PDF(pc) (7930KB)(134)       Save

    This study aimed to investigate the influence of particle size on the micropile by conducting theoretical analysis and model tests. The empirical relationship between the critical friction angle and the relative roughness at the pile-soil interface was established, and thus the critical friction angle could be determined quantitively in consideration of the particle size of sands. To emphasis the influence of particle size on the additional normal stress at the soil-pile interface, the shear band at the soil-pile interface was modelled as a hollow cylinder and then a new modified method was proposed based on the elastic cavity expansion theory. Only two new parameters, Poisson's ratio and the thickness of the shear band, were involved in the modified method, which was validated by comparison with model tests. It was found that the pile shaft friction was mainly determined by the pile roughness and the ratio of pile diameter to sand median size and the critical state angle at the pile-soil interface, while the additional normal stress mainly results from the pile roughness and the ratio of pile diameter to sand median size, respectively. The research could provide the valueable reference for the bearing capacity design of micropiles.

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    Review and prospect of the development of heat exchanger structure
    Wenjing DU,Junzhe ZHAO,Lixin ZHANG,Zhan WANG,Wanxiang JI
    Journal of Shandong University(Engineering Science)    2021, 51 (5): 76-83.   DOI: 10.6040/j.issn.1672-3961.0.2020.423
    Abstract416)   HTML36)    PDF(pc) (4892KB)(134)       Save

    The development of heat exchanger for more than 200 years was introduced. The generation and typical applications of heat exchangers with different structures were reviewed. Four heat exchangers with different structures including shell-and-tube heat exchanger, plate heat exchanger, microstructure heat exchanger, and printed circuit heat exchanger were described emphatically, and the development work of related geometric parameter optimization and structure improvement was carried out to realize heat transfer enhancement. The existing problems and limitations in the structure design of the heat exchanger were analyzed, and the specific suggestions and development trends for the structure improvement of the heat exchanger in the future were proposed.

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    Forward modeling analysis of seismic wave field for TGS360pro advanced prediction of groundwater: taking the karst model as an example
    ZHANG Mingcai, JU Guanghong, XIONG Zhangqiang, ZHANG Dazhou
    Journal of Shandong University(Engineering Science)    2021, 51 (3): 68-75.   DOI: 10.6040/j.issn.1672-3961.0.2020.158
    Abstract381)      PDF(pc) (8916KB)(132)       Save
    In order to avoid the occurrence of water gushing accident due to the inaccurate detection of the underground water storage state in front of the tunnel during the excavation of the tunnel, the tunnel geology survey TGS360pro System was used to accurately and efficiently detect the water-bearing body in front of the tunnel face by using the relation between the instantaneous amplitude and frequency of seismic wave signal and the rock structure plane, at the same time, based on the principle of TGS360pro tunnel Prediction System, the geological model with water-filled cave in front of the face was simulated by using spectral element method, through the stress curve, the numerical analysis results showed that the TGS360pro Tunnel Prediction System could effectively detect the water-rich condition in front of the tunnel, it had the prospect of popularization and application in tunnel excavation construction.
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    Evacuation simulation model based on multi-target driven artificial bee colony algorithm
    Xinlu ZONG,Jiayuan DU
    Journal of Shandong University(Engineering Science)    2021, 51 (3): 1-6.   DOI: 10.6040/j.issn.1672-3961.0.2020.259
    Abstract425)   HTML532)    PDF(pc) (4584KB)(128)       Save

    An evacuation simulation model based on multi-target driven artificial bee colony algorithm was presented. Based on the artificial bee colony algorithm, the visual field was used for each following bee to choose the individual with the best fitness value in the field as its visual leading bee and avoid blind choice. A multi-target driven artificial bee colony algorithm was proposed. The moving direction of each following bee was affected by multiple targets, including inertial leading bee, global optimal bee, historical optimal bee and visual leading bee. The experimental results showed that the multi-target driven artificial bee colony algorithm had higher efficiency and achieved better performance and more reasonable distribution in the case of larger number of evacuees. The model and algorithm presented could effectively improve evacuation efficiency and was suitable for the evacuation problem in multi-obstacle situation.

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    Small sample person re-identification combining Gabor features and convolution features
    FU Guixia, ZOU Guofeng, MAO Shuai, PAN Jinfeng, YIN Liju
    Journal of Shandong University(Engineering Science)    2021, 51 (3): 22-29.   DOI: 10.6040/j.issn.1672-3961.0.2020.232
    Abstract367)      PDF(pc) (6150KB)(125)       Save
    In the video surveillance, the limited available person images and unreliable data annotation led to the performance degradation of supervised person re-identification. To solve these problems, we proposed an unsupervised small sample person re-identification method that integrated Gabor features and convolution features. Gabor transform was used to extract multi-scale and multi-direction person texture and edge information, so as to realize the data augmentation of small sample person images in feature level. The redundant information was eliminated by feature encoding to improve the efficiency of feature similarity calculation. The convolutional auto-encoder network was adopted to extract the nonlinear deep convolution feature of pedestrian, which avoided the dependence of supervised learning algorithm on data annotation. The fusion of two heterogeneous features was applied to person similarity comparison, which implemented the feature augmentation of small samples and the improvement of person feature discrimination ability. Experiments were implemented based on Market-1501 and DukeMTMC-reID datasets, the rank-1 accuracy reached 74% and 67.1% respectively. The experimental results showed that the proposed network framework effectively improved the performance of small sample person re-identification.
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    Study on offshore wind farm overvoltage and reactive power compensation
    XU Dapeng, CAI Deyu, ZHAO Lanming, LIU Xumin
    Journal of Shandong University(Engineering Science)    2021, 51 (1): 94-99.   DOI: 10.6040/j.issn.1672-3961.0.2020.393
    Abstract494)      PDF(pc) (5532KB)(124)       Save
    This paper presented a new methodology for offshore wind farm grid-connection overvoltage and reactive power compensation. The methodology used DIgSILENT PowerFactory software for offshore wind farm modelling, including wind turbine, submarine cable, transformer and relevant control schemes. Moreover, dynamic simulations was performed in time-domain to analyze the active power, reactive power and voltage characteristics of the wind farm under different wind speed conditions. According to the results of the simulations, reactive power compensation devices were configured, and consequently the voltage and power factor condition of the offshore wind farm would be improved, which was also verified by the simulation results.
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    Novel guidewire modeling method based on Energy minimum theory
    WANG Yu, LIU Hao
    Journal of Shandong University(Engineering Science)    2021, 51 (1): 114-119.   DOI: 10.6040/j.issn.1672-3961.0.2020.364
    Abstract303)      PDF(pc) (4431KB)(122)       Save
    A high-performance guidewire model was demanded in the VR(virtual reality, VR)training system for endovascular interventional surgery. A new guidewire modeling method was proposed. This method used a cylindrical rigid body with hemispherical ends as the basic unit of the guidewire and the geometric characteristics of the model itself combined the principle of minimum energy to obtain the guidewire deformation parameters when the guidewire was inserted into the target blood vessel branch, which improved the accuracy and flexibility of the guidewire. Combined with the developed guidewire manipulator, the established guidewire achieved good performance and keeped synchronization with it during the experiment, which helped novices to immerse in the training environment.
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    Day-ahead optimal scheduling considering the constraints of UHVDC transmission and wheeling contracts
    Dexin LI,Chonglin ZONG,Jiarui WANG,Haifeng ZHANG,Chang LIU,Dawei HUANG
    Journal of Shandong University(Engineering Science)    2021, 51 (1): 69-75, 86.   DOI: 10.6040/j.issn.1672-3961.0.2020.361
    Abstract429)   HTML15)    PDF(pc) (3689KB)(121)       Save

    The operational characteristics of ultra-high voltage direct current (UHVDC) transmission and the impact of wheeling contracts on power grid operation and dispatching were analyzed, and a grid-optimized dispatching model considered the constraints of UHVDC transmission and inter-subnet wheeling contracts was established. The model aimed at the minimum operating cost of the power grid and the minimum of wind and photovoltaic curtailment, at the same time, the power constraints of the transmission and wheeling of AC and DC lines were considered, by adding two types of 0-1 variables that characterize power regulation, power up and power down, the stepped constraints of UHVDC transmission lines were expressed as linear equations of 0-1 mixed integers. Taking the improved IEEE39 node system as an example, the impact of UHVDC transmission and wheeling contracts on the grid′s renewable energy consumption was analyzed, and the effectiveness of the proposed method was verified.

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    Comprehensive protection scheme for grounding fault in low resistance grounding system
    HUANG Fuquan, WANG Tinghuang, ZHANG Haitai, LIU Zijun, LI Guodong
    Journal of Shandong University(Engineering Science)    2021, 51 (3): 113-118.   DOI: 10.6040/j.issn.1672-3961.0.2020.159
    Abstract400)      PDF(pc) (2199KB)(117)       Save
    Because the existing grounding protection in low resistance grounding system had imcomplete protection configuration, poor selectivity, low sensitivity and insufficient ability to detect high-imedance grounding fault, the characteristics of zero sequence current while single-phase grounding fault occured in low resistance grounding system was analyzied. With the help of longitudinal cooperation between the upper and lower protections, the multistage grounding protection based on zero sequence current and the high sensitivity grounding protection based on low setting and time delay were proposed, and also the grounding protection configuration scheme and the setting principles at all levels were discussed. Fault line selection method was proposed for the high-impedance grounding fault using the lateral comparasion of the amplitudes of zero sequence currents between the outlet of each feeder and the neutral line. The feasibility and reliability of the proposed comprehensive protection scheme for grounding fault were verified by the simulation in a typical small resistance grounding distribution network.
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    Vibration characteristics of flexible-blade Rushton impeller
    Xin LIU,Fengling YANG
    Journal of Shandong University(Engineering Science)    2020, 50 (5): 50-55.   DOI: 10.6040/j.issn.1672-3961.0.2020.009
    Abstract566)   HTML16)    PDF(pc) (1981KB)(117)       Save

    A natural frequency of a new type of flexible-blade Rushton impeller was studied to avoid a resonance phenomenon. The vibration characteristics of this impeller under stationary and rotating working conditions were experimentally investigated. Frequency domain characteristics were obtained by making Fast Fourier Transformation (FFT) of time domain characteristics. The results showed that a vibration energy of the impeller was mainly concentrated in a frequency band of 1-7Hz under the stationary state. A vibration energy of a rotating impeller with different speeds was mainly concentrated in a frequency bands corresponding to their respective peaks. Specifically, a peak acceleration distribution of acceleration data was shown in a frequency band of 47-52Hz. The acceleration amplitude increased significantly at 2.5r/s, and a main vibration frequency was equal to the natural frequency, which was 2.5Hz. So it was judged that resonance occured at this time. Therefore, the method of obtaining the resonance rotational speed through the test provided a basis for a reasonable selection of the rotational speed of the flexible-blade impeller.

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    Emission characteristics of PM1.0-bound polycyclic aromatic hydrocarbons(PAHs)from different stoves and fuels in rural areas
    DUAN Shengfei, YANG Lingxiao, LI Jingshu, GAO Hongliang, ZHANG Wan, ZHANG Xiongfei, QI Anan, WANG Pengcheng, WANG Yiming, TUO Xiong
    Journal of Shandong University(Engineering Science)    2021, 51 (1): 120-127.   DOI: 10.6040/j.issn.1672-3961.0.2020.513
    Abstract351)      PDF(pc) (4446KB)(117)       Save
    To study the emission factors and emission characteristics of PM1.0-bound PAHs from the combustion of different fuels and improve stoves in rural areas, the samples produced by 8 fuels burned in 2 improved stoves were collected using the dilution channel method, and the concentration of PAHs was analyzed. The results showed that the emission factor was in the range of 0.38~39.37 mg·kg-1. When the same fuel was burned in different improved stoves, the gasifier stoves emission factor of PAHs was lower than the decoupling stoves. The order of PAHs emission factors of various fuels burned in the gasifier stove was EFbulk coal>EFcorn straw>EFbituminous coal briquette>EFpine wood>EFoak wood>EFsemi-coal≈ EFanthracite briquette>EFcorn straw briquette. Among biomass fuels, PHE, PLA, and PYR were the main species of PAHs produced by combustion, while the dominant species in coals were PHE, FLA, PYR, and BbF. The proportion of LMW PAHs produced by the gasifier stove was higher than the decoupling stove, while the proportion of MMW PAHs and HMW PAHs produced by the gasifier stove was lower than the decoupling stove. In the case of meeting the heating demand of residents, it was estimated that the best combination was gasifier stove+semi-coke, anthracite briquette, or corn straw briquette.
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    Multi-kernel combination method based on rank spatial difference
    WANG Mei, XUE Chenglong, ZHANG Qiang
    Journal of Shandong University(Engineering Science)    2021, 51 (1): 108-113.   DOI: 10.6040/j.issn.1672-3961.0.2020.248
    Abstract375)      PDF(pc) (444KB)(114)       Save
    A multi-kernel combination method based on rank spatial difference was proposed in this paper. samples were grouped according to characteristics, different kernel functions are used to train the grouped data, and the parameters of the kernel function are optimized by grid search method. Two kernel functions were selected from the alternative kernel functions, and the data divided into two groups were respectively put into the corresponding kernel function for mapping. Then the rank spatial difference of the data after the kernel function mapping was judged to provide reference for the selection of the basic kernel function. The wine data set, the breast cancer data set and the wine quality data set were selected for the experiment to verify that when the data were mapped by the selected basic kernel function, the greater the rank space difference was, the higher the classification accuracy was. The experimental results showed that the method was feasible for the selection and combination of basic kernel functions.
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    Image-dependent fusion method for saliency maps
    Ye LIANG,Nan MA,Hongzhe LIU
    Journal of Shandong University(Engineering Science)    2021, 51 (4): 1-7.   DOI: 10.6040/j.issn.1672-3961.0.2020.266
    Abstract301)   HTML30)    PDF(pc) (4939KB)(113)       Save

    A saliency fusion method based on ridge regression was proposed to obtain better detection performance. The nearest neighbor set of the image to be detected was searched in the training set. The ridge regression method was used to estimate the fusion coefficients of different saliency maps. The saliency maps of different detection methods were fused. This method fully considered the differences of detection methods, and solved the problem of saliency map fusion in the absence of benchmark binary annotations. The AUC value of the proposed method was 0.911 on ECSSD dataset. The AUC value of the proposed method was 0.987 on HKU-IS dataset. The AUC value of the proposed method was 0.953 on DUT-OMRON dataset. The efficiency of the proposed method was verified by experimental results.

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    Multiobjective dynamic economic emission dispatch differential evolution algorithm based on elites cloning local search
    WU Huihong, QIAN Shuqu, LIU Yanmin, XU Guofeng, GUO Benhua
    Journal of Shandong University(Engineering Science)    2021, 51 (1): 11-23.   DOI: 10.6040/j.issn.1672-3961.0.2020.050
    Abstract361)      PDF(pc) (5001KB)(111)       Save
    An efficient multiobjective differential evolution algorithm based on elites cloning local search scheme was proposed to solve complex dynamic economic emission dispatch. The conventional differential evolution(DE)algorithm was used as the framework of the proposed algorithm. A cloning operator was developed to enhance the exploration and exploitation ability of elites in the DE algorithm. The elite population to be cloned was established by a dynamic selection mechanism for enhancing the global search ability of the proposed algorithm. To validate the effectiveness of the proposed algorithm, the IEEE 30 bus 10-generator and 15-generator systems were studies as test cases in numerical experiments. The simulation results indicated that the Pareto-optimal front obtained by the proposed algorithm presented a superior performance in convergence and extension over the other reported results recently. As a result, the results were able to provide decision solutions more extensively for decision-makers in power system dispatch.
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    True mechanical model of underground pipe corridor supported by piles
    LI Lianxiang, WANG Lei, ZHAO Yongxin, JI Xiangkai
    Journal of Shandong University(Engineering Science)    2021, 51 (1): 60-68.   DOI: 10.6040/j.issn.1672-3961.0.2020.294
    Abstract408)      PDF(pc) (4922KB)(108)       Save
    In order to study the influence of the pile support system on the real mechanical model of the pipe gallery structure, taking an underground comprehensive pipe gallery project in Jinan as an example, the whole process of the project was simulated by using the Plaxis 3D finite element software. It was found that the stress on the side plate of the underground pipe gallery under the pile support was distributed in three sections: first increase, then decrease, then increase, and obviously less than the static earth pressure, and the internal force of the side plate of the pipe gallery was less than the traditional square law. According to the simulation results, the stress distribution curve and its simplified curve of the side plate of the pipe gallery were obtained by changing the thickness of the covered soil on the top of the gallery. The calculation results showed that the internal force of the side plate of the pipe gallery calculated by the simplified curve was in good agreement with the simulation value, that was to say, the simplified curve had better applicability. According to the simplified curve to calculate the side load of the pipe gallery, the designed pipe gallery structure was more practical, economic and reasonable.
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    Median calculation algorithms based on GPU in OLAP
    WU Zhenpeng, ZHANG Jian, FAN Xingqi, LI Cuiping
    Journal of Shandong University(Engineering Science)    2021, 51 (3): 7-14.   DOI: 10.6040/j.issn.1672-3961.0.2019.508
    Abstract371)      PDF(pc) (3119KB)(107)       Save
    An algorithm for one of the holistic aggregate operations in online analytical processing(OLAP)called Median was proposed based on graphics processing unit(GPU), which was named GPU-Median algorithm. This algorithm obtained the median of a series of data by segmenting the data, sorting the data by segments,cutting the data preceding the global median, and finally merging the uncut data. Through the algorithm above much time spent on global sorting was saved. Then an algorithm called GPU-Median+was presented in order to optimize and extend the GPU-Median algorithm. This algorithm implemented the aggregate operations through the collaboration of CPU and GPU, which used GPU to deal with segments of data and CPU to deal with global data. Experiments and analysis proved that the GPU-Median + algorithm reduced the time complexity of the median calculation from O(n2)to O(n)compared to the CPU algorithm,and that the GPU-Median + algorithm reduced a third of the calculation time compared to the radix sort algorithm on the GPU. The application of this algorithm enabled the GPU to improve its ability of parallel calculations when calculating the holistic aggregate function in OLAP, thus providing a new idea for improving the query performance of OLAP.
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    Location optimization of median BRT station at intersection
    GUO Rongrong, ZHANG Ruhua, MA Xinhui, GUO Senyao
    Journal of Shandong University(Engineering Science)    2021, 51 (3): 61-67.   DOI: 10.6040/j.issn.1672-3961.0.2020.345
    Abstract328)      PDF(pc) (1618KB)(98)       Save
    Based on the optimal comprehensive time efficiency of BRT vehicles and arriving passengers, a station selection optimization method was proposed. The time efficiency model was established and calculated by fuzzy analytic hierarchy process and genetic algorithm. Huanggang Road Station in Jinan was selected for case analysis. The results showed that the larger the weight of BRT operation time in a measurement unit was, the smaller the weight of arrival passenger travel time was, and the greater the buffer distance when the time efficiency was optimal. When the case station was set up at 25 meters downstream of the intersection, the efficiency of comprehensive time was the most optimal, which was 20% higher than the current situation.
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    Influence of shear span ratio on seismic performance of hollow pipe pier with slot connection
    SU Sibo, WANG Guoqing, JIA Xianzhuo, LI Zhicong, HUANG Zhigang
    Journal of Shandong University(Engineering Science)    2021, 51 (1): 39-45.   DOI: 10.6040/j.issn.1672-3961.0.2020.387
    Abstract399)      PDF(pc) (7608KB)(97)       Save
    In order to study the influence of shear span ratio on seismic performance of slotted pipe pier with grouted core, based on the bridge engineering of Rongwu New Line Highway, ABAQUS finite element analysis software was used to simulate three kinds of slotted connection pipe pier with different shear span ratio, and the full-scale model of slotted connection pipe pier were made, and the horizontal cyclic load test under constant axial force was carried out to verify the reliability of the finite element model. The results showed that the failure modes of three different shear span ratios were shear failure, bending shear failure and bending failure. With the increase of shear span ratio, the hysteretic performance, energy dissipation capacity and ductility performance of the pipe pier had been significantly improved, but its bearing capacity and residual displacement had little change, the initial stiffness had been strengthened, but the ultimate failure stiffness were basically the same.
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