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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 Abstract （3261）   HTML （220）    PDF（pc） （4892KB）（2512）       Knowledge map    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. Table and Figures | Reference | Related Articles | Metrics

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A research survey of driver drowsiness driving detection YANG Jucheng, WEI Feng, LIN Liang, JIA Qingxiang, LIU Jianzheng Journal of Shandong University(Engineering Science)    2024, 54 (2): 1-12.   DOI: 10.6040/j.issn.1672-3961.0.2023.279 Abstract （864）      PDF（pc） （1359KB）（1085）       Knowledge map    Save Reference | Related Articles | Metrics

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Fitting heat transfer coefficient correlation on flow boiling and error analysis for the helically coiled tube JI Cuilian, HAN Jitian, YIN Jing, CHEN Changnian, REN Libo, KONG Lingjian JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2014, 44 (5): 83-87.   DOI: 10.6040/j.issn.1672-3961.0.2014.020 Abstract （1995）      PDF（pc） （1407KB）（1585）       Knowledge map    Save In order to develop flow boiling heat transfer coefficient correlations for helically coiled tube, based on the mechanism of flow boiling heat transfer. The Dn factor was introduced to consider complex pipeline effects on flow boiling heat transfer. The index of the Dn factor was gained by using the regression method. And relation of the ratio of the experimental and predicted values with the mass flow rate and vapor quality was further analyzed. A new heat transfer coefficient correlation of flow boiling in helically coiled tube was developed. The applicability for the heat transfer coefficient correlation was validated by experimental data of flow boiling heat transfer in helically coiled tube with R134a. The MRE and the RMSE were used to measure the accuracy of regression results, with MRE and RMSE being 8.23% and 0.532, respectively. The MRE and the RMSE were small, the regression results conformed to the requirements. Therefore, the method is very applicable, and is worthy of popularization. Reference | Related Articles | Metrics

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Bound gait controlling method of quadruped robot MENG Jian, LI Yibin, LI Bin JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2015, 45 (3): 28-34.   DOI: 10.6040/j.issn.1672-3961.0.2014.328 Abstract （2499）      PDF（pc） （3687KB）（1967）       Knowledge map    Save Aiming at the problem of running control of quadruped robot, a running control method based on bound gait was proposed. The bound gait of the quadruped robot was implemented by fast and small range swing motion of the legs. A finite state machine was used to separate one complete cycle of motion into six stages, three stages for fore legs and three for hind legs respectively. In contact and buffering stage, vertical spring-damper model was used; in thrust stage, virtual model was used to adjust the thrust direction of the legs; and in swing stage, Bezier curve was used to plan the trajectory of the toes. By constructing a virtual model with the same size and mass with the hydraulic driven quadruped robot SCalf-II in the dynamics simulation software, the control method was verified and tested, simulation results showed that the robot came into a cyclic bounding motion with strong periodicity after five periods, the speed vibration in forward direction was small, the joint range of motion, speed and torque were all within the range of the design objective of SCalf-II, which verified the correctness and effectiveness of the proposed method. Reference | Related Articles | Metrics

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Calibration of micro-parameters of parallel bonded model for rocks JIANG Mingjing, FANG Wei, SIMA Jun JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2015, 45 (4): 50-56.   DOI: 10.6040/j.issn.1672-3961.0.2014.183 Abstract （2090）      PDF（pc） （2117KB）（2760）       Knowledge map    Save The micro-parameters of parallel bond model could not satisfy the compressive strength and tensile strength simultaneously, this was a problem in the simulation of rocks. A set of uniaxial tension tests and uniaxial compression tests of rocks were simulated to investigate this problem. First, DEM specimens with different porosity ratio and different nonuniform coefficient were calibrated according to the laboratory test results of Lac du Bonnet granite. Second, the deficiency of the parallel bond model was pointed out and the improved methods were proposed from the perspective of microscopic failure mechanism. The simulation results showed that the microscopic parameters satisfied tension strength was one order of magnitude deviated from the microscopic parameters, which could also satisfy compression strength. Tensile characteristics and shear characteristics were considered in the parallel bond model, while the influence of normal stress on the bond was ignored. This was the reason that the tension-compression strength ratio of rock was different from the experimental result. It was advised to use clumped particle model which could simulate particle breakage or cementation model based on laboratory tests. Reference | Related Articles | Metrics

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Preparation of SiO2-ZrO2 compound high temperature adhesive HE Zhao-pin, SHI Yuan-chang*, SUN Li-bo, LI Bo, YUAN Ye, LIU Jiu-rong JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2013, 43 (1): 104-108.   Abstract （807）      PDF（pc） （1766KB）（3196）       Knowledge map    Save In order to improve the high temperature resistant performance of traditional silicate inorganic adhesive, the new-type compound high temperature adhesive was prepared by sol-gel method with tetraethyl orthosilicate and zirconium oxychloride. Its thermal stability and bonding performance were studied by characterizing the structure, phase composition, heat change and appearance. The results showed that pH was of great influence on the sol-gel reaction process, and the optimal pH was 3. The preparation methods had obvious influence on the microstructure of SiO2-ZrO2 compound adhesive. Dispersion method was better than the in situ synthesis method for preparing the compound adhesive. The molar ratio of raw materials was an important influencing factor on the performance of the compound adhesive. The SiO2-ZrO2 compound adhesive could provide good bonding performance and good thermal stability when the Si-Zr molar ratio was 1∶3. Related Articles | Metrics

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Design of highperformance CML ternary D flipflop based on BiCMOS ZHAO Xiang-hong1, 2, SHEN Ji-zhong2* JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2013, 43 (3): 99-104.   Abstract （867）      PDF（pc） （1850KB）（2118）       Knowledge map    Save A simple-structure high-performance CML ternary D flip-flop based on BiCMOS was proposed, which combined both advantages of BiCMOS and CML circuits, and included high-speed and strong drive ability of BiCMOS circuits and high speed low swing and low noise of CML circuits. Using TSMC 180nm process, the results of simulations carried out by HSPICE illustrated that the proposed circuit could not only have correct logic function, but also gain improvements of 95.6％-98.4％ in average D-Q delay and 16.2％-96.8％ in PDP compared with the advanced ternary D flip-flops. Furthermore, the work frequency  could perform up to 15GHz. All of the results proved that the proposed circuit was suitable for high-speed and high-frequency applications. Related Articles | Metrics

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Optimization of bank counter setting based on queuing theory CAI Wen-jing1, GE Lian-sheng2 JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2013, 43 (3): 23-29.   Abstract （918）      PDF（pc） （829KB）（2474）       Knowledge map    Save In order to reduce the waiting time of customers in the current banking system, a queuing theory based optimization model of banking queuing system was developed. The process of conducting service at the bank counters was regarded as random service system. A detailed design of bank counters’ optimization was given based on the basic features of this system. Additionally, a concrete analysis of the system optimization using queuing theory according to two respective aims was presented, and then a new way to decide the appropriate number of bank counters was illustrated with an example. Related Articles | Metrics

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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 Abstract （3592）   HTML （394）    PDF（pc） （2943KB）（1137）       Knowledge map    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. Table and Figures | Reference | Related Articles | Metrics

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Development status and prospects of pavement state sensing technology under vehicle-road interaction MA Tao, WANG Renzhi, CHEN Feng, SONG Yitao, LI Yue, MA Yuan Journal of Shandong University(Engineering Science)    2024, 54 (5): 1-28.   DOI: 10.6040/j.issn.1672-3961.0.2024.011 Abstract （432）      PDF（pc） （9683KB）（189）       Knowledge map    Save Reference | Related Articles | Metrics

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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 Abstract （3618）   HTML （203）    PDF（pc） （13090KB）（1564）       Knowledge map    Save 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. Table and Figures | Reference | Related Articles | Metrics

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An attitude estimation algorithm for human body based on multi-sensor information fusion LI Jing-hui, YANG Li-cai* JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2013, 43 (5): 49-54.   Abstract （825）      PDF（pc） （1801KB）（3437）       Knowledge map    Save Aiming at the problems of poor stability and short precision in traditional attitude estimation algorithms, a method based on multi-sensor information fusion was proposed. The quaternion was used to calculate the attitude changes, and deviations between measurements and observations from the Inertial Measurement Unit(IMU) were managed by PI regulator. The complementary filtering was adopted for multi-sensor information fusion, and the realtime attitude was got. Experimental results showed that the algorithm could output the high precision attitude steadily. Related Articles | Metrics

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Application of fiber optic sensing technology in road traffic SONG Xiuguang, ZHAO Tao, BI Yanmei, ZHANG Zihao, DU Cong, TIAN Yuan, KONG Xiaoguang Journal of Shandong University(Engineering Science)    2024, 54 (2): 13-26.   DOI: 10.6040/j.issn.1672-3961.0.2023.252 Abstract （454）      PDF（pc） （1745KB）（536）       Knowledge map    Save Reference | Related Articles | Metrics

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Design of self-adaptive sliding mode controller with finite time convergence ZHAO Zhan-shan1,2, ZHANG Jing3, SUN Lian-kun, DING Gang1 JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2012, 42 (4): 74-78.   Abstract （881）      PDF（pc） （1345KB）（2775）       Knowledge map    Save A new self-adaptive sliding mode controller algorithm was proposed for a class of uncertain nonlinear systems with unknown but bounded uncertainties. The proposed solution  could stabilize the status of these systems in finite time by using geometric homogeneity and integral sliding mode control. In order to solve system uncertainties with unknown but bounded, the corresponding adaptation law was developed to evaluate the gain of the controller. The theoretic analysis based on Lyapunov theory proved that the systems with the proposed controller could be stabilized in finite time. Simulation results showed that the proposed adaptive sliding mode controller could achieve better robustness and adaptation against uncertainties. Related Articles | Metrics

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Review and prospect of research on power system inertia with high penetration of renewable energy source Hengxu ZHANG,Zhimin GAO,Yongji CAO,Hao QIN,Dong YANG,Huan MA Journal of Shandong University(Engineering Science)    2022, 52 (5): 1-13.   DOI: 10.6040/j.issn.1672-3961.0.2022.237 Abstract （2076）   HTML （106）    PDF（pc） （4575KB）（1867）       Knowledge map    Save With the aim of carbon peak and carbon neutrality, the integration of high-proportion renewable energy sources (RESs) makes the low-inertia characteristic of the new power system more obvious. In order to ensure power system security and stability, and support the integration of RESs, the research on the power system inertia was reviewed and prospected. The essence of the power system inertia was introduced, and the correlation among the conventional inertia, virtual inertia and equivalent inertia was discussed, on which the physical significance of the virtual inertia was revealed. From the viewpoints of the sources of inertia, the research on the virtual inertia control of the wind machine, photovoltaic generation, and energy storage system was summarized. Additionally, the assessment methods of power system inertia were reviewed. The important issues to be focused in the research area of power system inertia were summarized, and the suggestions for further studies were provided. Table and Figures | Reference | Related Articles | Metrics

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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 Abstract （3411）   HTML （634）    PDF（pc） （2579KB）（2619）       Knowledge map    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. Table and Figures | Reference | Related Articles | Metrics

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High precision algorithm of metal detector based on balance coil BAI Shuzhong, DONG Chunyang JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2017, 47 (4): 83-88.   DOI: 10.6040/j.issn.1672-3961.0.2016.112 Abstract （1838）      PDF（pc） （1807KB）（1679）       Knowledge map    Save Metal detector is widely used in food security and industrial manufacture. In order to solve the product effect problem which used only amplitude feature, the dual channel digital detecting algorithm was put forward based on amplitude and phase information, also the balance coil mathematical model was built, and the metal signal feature was deeply analyzed. Through the coordinate orientating,the amplitude and phase information of metal could be exactly extracted, product learning and clustering algorithm could efficiently separate the metal signal and product effect signal. The experiment results showed that the phase information could separate different material metal effectively, cooperated with the amplitude information, the dual channel digital detecting algorithm could extract the metal information accurately and detect the metal with strong product effect. Reference | Related Articles | Metrics

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Barbalat Lemma and its application in analysis of system stability MIN Ying-ying,LIU Yun-gang JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    Abstract （1567）      PDF（pc） （269KB）（8917）       Knowledge map    Save A set of primary formulations of Barbalat Lemma and its simple alternatives are summarized. The relationships among those formulations and their applicable scopes are investigated. The applications of Barbalat Lemma in analyzing asymptotically convergence of the system, adaptive control design and Lp stability are discussed via three examples. Related Articles | Metrics

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Unit commitment considering alternating current power flow constraints PAN Zhi-yuan1, HAN Xue-shan1*, LIU Chao-nan2 JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2012, 42 (2): 130-137.   Abstract （696）      PDF（pc） （1230KB）（2362）       Knowledge map    Save With the parallel development of  distributed generation technology and  large power grid technology, a great amount of renewable energy generation was introduced to the electrical power grid. Under this circumstance, a unit commitment model was established by considering the constraints of transmission safety using AC(alternating current) power flow.  This model also involved reactive and voltage constraints, as well as safe operation limits of generators. According to the Benders decomposition, the model was decomposed into a master problem and a sub-problem. The master problem could solve the unit commitment without AC constraints, and then the sub-problem could check the AC constraints according to the result of the master problem. Benders cuts might develop from the sub problem, and the cuts would form additional associated constraints, which could connect the master problem and the sub problem. Simulation results of modified IEEE-14 buses case proved that the proposed method could effectively solve unit commitment problems with constraints of AC power flow. Related Articles | Metrics

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A microblog rumor events detection method based on C-GRU Lizhao LI, Guoyong CAI, Jiao PAN Journal of Shandong University(Engineering Science)    2019, 49 (2): 102-106.   DOI: 10.6040/j.issn.1672-3961.0.2018.189 Abstract （2504）   HTML （49）    PDF（pc） （1249KB）（1129）       Knowledge map    Save A microblog rumor events detection model based on convolution-gated recurrent unit(C-GRU) was proposed. Combining the advantages of CNN and GRU, the microblog event′s posts was vectorized. By learning the features representation of the microblog windows through the convolution layer of CNN, the features of microblog windows was spliced into a sequence of window feature according to the time order, and the sequence of window feature was put into the GRU to learn feature representation of sequence for rumor events detection. Experimental results from real data sets showed that this model had better ability to rumor detection than other models based on traditional machine learning, CNN or RNN. Table and Figures | Reference | Related Articles | Metrics

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Model of contact angle of hydrophobic surface based on minimum Gibbs free energy SONG Hao, LIU Zhanqiang, SHI Zhenyu, CAI Yukui JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2015, 45 (2): 56-61.   DOI: 10.6040/j.issn.1672-3961.0.2014.272 Abstract （1799）      PDF（pc） （1432KB）（2021）       Knowledge map    Save Based on the function of Young used for smooth surface and the model of Cassie-Baxter used for rough surface, the prediction model for contact angle of hydrophobic surface based on minimum Gibbs free energy was proposed. The model for contact angle prediction was then modified by considering the influence of skew walls on the contact line between gas-liquid. The effects of hydrophobic surface material properties and geometric parameters on contact angle were analyzed based on the modified model. The results showed that, under the same condition of machined micro-surface, the contract angle on the hydrophobic surface root was larger than that on the hydrophilic one. Besides, for the Cassie-Baxter model, the larger radio between the width of groove and the width of convex was, the larger contract angle was. Reference | Related Articles | Metrics

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Construction and analysis on typical working cycle of wheel loader MA Xiangming, SUN Xia, ZHANG Qiang Journal of Shandong University(Engineering Science)    2015, 45 (5): 82-87.   DOI: 10.6040/j.issn.1672-3961.0.2015.095 Abstract （1021）      PDF（pc） （1288KB）（820）       Knowledge map    Save In order to obtain more precise operating parameters of typical working cycle and simulate the fuel consumption, a constructing method of typical working cycle for wheel loader was proposed based on kinetic sequences and operating characteristics. Thirteen characteristic parameters, including speed-torque area etc., were defined to evaluate the variation of operating parameters during working process. Meanwhile, the kinetic sequences were classified into five clusters by the adoption of the Principal Component Analysis and fuzzy C-means algorithm. Afterwards, the sequences with minimum Euclidean distance in each cluster were selected to constitute the typical working cycle. The results showed that parameters of the test condition and the typical working cycle, such as acceleration and speed, had the similar distribution; fuel consumption based on the typical working cycle simulation was 0.176 L with an error of 4.7%, which was within the scope of the engineering allowable error. The proposed method could be effectively employed to process and analyze the test data of wheel loader and construct the typical working cycle, which was also greatly helpful to further study the fuel economy of loader working cycle. Reference | Related Articles | Metrics

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Multiple objective and attribute decision making based on the subjective and objective weighting SONG Dongmei, LIU Chunxiao, SHEN Chen, SHI Xuefa, ZANG Lin, FENG Wenqiang JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2015, 45 (4): 1-9.   DOI: 10.6040/j.issn.1672-3961.0.2014.306 Abstract （2163）      PDF（pc） （1455KB）（2031）       Knowledge map    Save For main defects of traditional subjective weighing and objective weighing method in the process of multi-objective and multiple attribute decision, a new weight way combined subjective and objective weighting method was proposed. Subjective weigh method has advantages of considering three different attitudes (pessimistic, neutral, optimistic) of the policy makers. Objective weighting method was based on the CRITIC method and the Entropy value method, which fully considered the discrete, correlation and contrast intensity of the data. Finally, linear group legal and multiplication operator were used to combine subjective and objective weighting method. The feasibility and practicability of the proposed method was proved by the experiment of assessment on the anti-interference ability of the communication equipment. Reference | Related Articles | Metrics

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Global and local multi-view multi-label learning with active three-way clustering ZHU Changming, YUE Wen, WANG Panhong, SHEN Zhenyu, ZHOU Rigui Journal of Shandong University(Engineering Science)    2021, 51 (2): 34-46.   DOI: 10.6040/j.issn.1672-3961.0.2020.234 Abstract （839）      PDF（pc） （1030KB）（1341）       Knowledge map    Save In order to consider the uncertain belongingness relationship between instances and clusters and then extend the application scopes of global and local multi-view multi-label learning, an algorithm of global and local multi-view multi-label learning machine with active three-way clustering(GLMVML-ATC)was proposed. With the usage of active three-way clustering strategy, the belongingness of instances to a cluster depended on the probabilities of uncertain instances belonging to core regions. This made local label correlations more authentic, which enhanced the performances of multi-view multi-label learning machines further and accelerated their development. Experimental results validated that GLMVML-ATC improved the classification performances with 3% at least, while the added training time less than 7%. It was superior to the classical multi-view learning machines and multi-label learning machines. Reference | Related Articles | Metrics

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On comparison and selection of the wave spectrum in realtime rendering of the irregular ocean wave CHEN Li-ning, JIN Yi-cheng, REN Hong-xiang, YIN Yong JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2013, 43 (6): 47-52.   Abstract （1953）      PDF（pc） （1289KB）（2597）       Knowledge map    Save The Phillips spectrum was widely applied in real-time rendering of the irregular ocean wave. The structure of the Phillips spectrum was analyzed, and the frequency spectrum and directional distribution function of the Phillips spectrum were calculated. The frequency spectrum was similar with the P-M spectrum, so the constant A of the Phillips spectrum was computed by reference to the P-M spectrum, and the spectral wind speed was clarified. In addition to the Phillips spectrum, other spectra were tried. The P-M spectrum and the directional distribution function of the cos(-2s) form were used to construct the PM-cos2s spectrum, and the JONSWAP spectrum and the direction distribution function of the Poisson form were applied for constructing the J-Po spectrum. The three spectra mentioned above were used for rendering ocean wave, and the rendering results were compared. The waves rendered by the Phillips spectrum or PM-cos2s spectrum reflected the wind speed effect, and the wave generated by the J-Po spectrum showed the wind speed effect along with the fetch length effect. The frame rate of the three spectra shared the same value. Because the wave produced by the J-Po spectrum reflected the wind speed and fetch length influence, and the generated wave distributed in (-π,π］ of the wind direction, the J-Po spectrum was more suitable for the maritime simulator. Related Articles | Metrics

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An image quality assessment model based on structure feature LIANG Min-yu, SUN Quan-sen* JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2012, 42 (3): 52-56.   Abstract （730）      PDF（pc） （1503KB）（1938）       Knowledge map    Save As image structure feature is closely related to the human visual system, a new method based on structure feature was proposed to improve the result consistency with a subjective visual effect. First, image structure features were extracted though experience. And then various structural components were calculated with different weights, according to different sensitivities of eyes to image regions. Finally, a new model was proposed with linear regression. Experimental results on different kinds of images showed that the new method had high efficiency and accuracy compared to the PSNR and RMSE, and had a better consistency with a subjective visual effect. Related Articles | Metrics

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Eigenvector selection in spectral clustering based on Bagging WANG Xing-liang, WANG Li-hong*, LI Hai-jun JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2013, 43 (2): 35-41.   Abstract （910）      PDF（pc） （1485KB）（2198）       Knowledge map    Save For the spectral clustering algorithm, the largest k eigenvectors of the affinity matrix derived from the dataset were not always able to find the structure of dataset effectively. An eigenvector selection algorithm in spectral clustering based on Bagging was proposed in order to select better eigenvectors. The  eigenvectors were evaluated by pairwise constraints score. First, some eigenvectors were ranked according to their constraint scores, and then the suitable eigenvectors were selected from the ranking list, finally the optimal combination of k eigenvectors was obtained by Baggingbased ensemble algorithm. The better eigenvectors could be achieved. Experimental results on UCI benchmark datasets showed that this algorithm could gain satisfactory prediction results. Related Articles | Metrics

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Mechanical design and gait planning of a hydraulically actuated quadruped bionic robot LI Yi-bin1, LI Bin1,2, RONG Xue-wen1, MENG Jian1 JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2011, 41 (5): 32-36.   Abstract （1512）      PDF（pc） （1531KB）（7105）       Knowledge map    Save A hydraulically actuated quadruped bionic robot has been developed by Center for Robotics at Shandong University is described in this paper. The objective is to design a highly dynamic and high load quadruped robot that enables the adaptation to complex terrain. Based on mule／horse creature bionics, the leg configuration with passive structure and hydraulic actuation are met the needs of stability control and high load capacity. And the stability dynamic trotting gait of the quadruped robot is planned based on the forward kinematics and inverse kinematics. Experiments of the developed quadruped bionic robot platform show the rationality of mechanical design and the effectiveness of gait planning. Related Articles | Metrics

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A trajectory prediction-based edge offloading strategy for internet of vehicles ZHAO Xiaoyan, GAO Yuanzhi, ZHANG Jiale, ZHANG Junna, YUAN Peiyan Journal of Shandong University(Engineering Science)    2024, 54 (1): 52-62.   DOI: 10.6040/j.issn.1672-3961.0.2023.149 Abstract （203）      PDF（pc） （8259KB）（356）       Knowledge map    Save Reference | Related Articles | Metrics

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Survey of outlier detection technologies CHEN Bin, CHEN Song-Can, PAN Zhi-Song, LI Bin JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2009, 39 (6): 13-23.   Abstract （1796）      PDF（pc） （1025KB）（4479）       Knowledge map    Save Outlier detection aims to detect those data that significantly deviate from the expected behavior, and thus is widely applied in many fields, such as, machine fault detection, intrusion detection, fraud detection and data preprocessing. Hence, there exist many generic and special algorithms for outlier detection under the unsupervised and supervised learning framework. But up to now, there still has been no clear classification in this aspect. To provide a structural view, the review of the state-of-the-art statistics-based methods for outlier detection was focusedon, and a simple classification was given in this aspect. Moreover,the equivalence between some outlier detectors in depth is particularly discussed. Related Articles | Metrics

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Performance of the high pressure stage compressor of a two-stage turbocharging system HE Yi-tuan JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2010, 40 (4): 129-132.   Abstract （736）      PDF（pc） （779KB）（1889）       Knowledge map    Save To make the high pressure(HP) stage compressor and the low pressure(LP) match with optimization and improve the efficiency of the whole two-stage turbo-charging system, the performance of a HP stage compressor was studied on a two-stage turbo-charging system test bench. In the turbo-charging system, the fresh air was first precompressed through the LP stage compressor to get the HP stage compressor′s inlet condition with high pressure ＆ high temperature. An intercooler was set between the HP and LP stage compressors. To each test curve had the same rotation speed, and the inlet temperature of the HP stage compressor was kept unchanged. The test results showed that there was much difference between the corrected speed and actual speed of the HP stage compressor only because the increase of its inlet temperature. In order to get the preconcerted pressure ratio, the speed of the HP stage compressor should be much improved. The corrected air mass flow of HP stage compressor was much less than its measured air mass flow, which was mainly because the great increase of inlet pressure of the HP stage compressor. In order to avoid a surge of the HP stage compressor, its inlet pressure should be controlled. Related Articles | Metrics

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Prediction method of wind power and PV ramp event based on deep learning Zhixiang LIANG,Xiaoming LIU,Ying MU,Yutian LIU Journal of Shandong University(Engineering Science)    2019, 49 (5): 24-28.   DOI: 10.6040/j.issn.1672-3961.0.2019.132 Abstract （1823）   HTML （26）    PDF（pc） （1178KB）（1036）       Knowledge map    Save With the gradual increase of the renewable energy penetration rate, the ramp event that caused the unbalanced active power occured sometimes, and even a large load loss. Due to the insufficient accuracy of wind power and photovoltaic prediction, there were many operational scenarios to be considered. The time domain simulation could not meet the online assessment requirements. A method based on deep learning was proposed in this paper. Considering the generation unit and tie line adjustment ability, the stacked denoising autoencoder was used to extract each layer feature to train support vector machine. The wind power, photovoltaic and load forecast data, and the power of the tie line at the previous moment were taken as inputs, and whether the ramp event occured as an output. The vector machine was used to quickly predict whether a ramp event occured. The simulation results of practical power grid showed that the proposed method was fast and accurate. It could effectively identify ramp events. Table and Figures | Reference | Related Articles | Metrics

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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 Abstract （1452）      PDF（pc） （8916KB）（727）       Knowledge map    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. Reference | Related Articles | Metrics

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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 Abstract （2235）   HTML （98）    PDF（pc） （4362KB）（1013）       Knowledge map    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. Table and Figures | Reference | Related Articles | Metrics

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Cloud robotics: concept, architectures and key technologies TIAN Guohui, XU Yaxiong JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2014, 44 (6): 47-54.   DOI: 10.6040/j.issn.1672-3961.0.2014.282 Abstract （2155）      PDF（pc） （1959KB）（2492）       Knowledge map    Save The technology of cloud robotics is the combination of cloud computing and robotics. It can bring great advantages in task execution and resource sharing for robots, and has become a hot topic in intelligent robot research field. In this paper, the developments of cloud robotics, key technologies, main platforms, main architectures and application prospects were comprehensively analyzed. Firstly, the concept arose of cloud robotics and its developments were introduced, and also the key technologies were given. Secondly, three main cloud service platforms were horizontally contrasted, and the main architectures of cloud robotics were analyzed. Finally, the application prospects for cloud robotics were comprehensively presented. Reference | Related Articles | Metrics

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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 Abstract （1094）      PDF（pc） （6150KB）（530）       Knowledge map    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. Reference | Related Articles | Metrics

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Analysis on influence factors of the earlyage cracking of concrete pavement WANG Hao1, LI Peng-cheng2*, MAO Hong-lu2, SUN Ren-juan2, GE Zhi2 JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2012, 42 (5): 108-112.   Abstract （729）      PDF（pc） （1799KB）（1342）       Knowledge map    Save The software HIPERPAV was adopted to analyze the major influential factors of the earlyage cracking of concrete pavement, which including the slab thickness, fly ash, curing method and time, construction time, paving season and time of sawing. The results showed that the stressstrength ratio of slab constructed in summer was lower than that in winter, and the pavement slab without saw cutting was more likely to produce the earlyage random cracking than the slab with cutting. In addition, the proper mixture ratio, construction time and curing method could significantly decrease or prevent the earlystage cracking. Related Articles | Metrics

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Finite-time stability analysis and control design of nonlinear system XIN Dao-yi,LIU Yun-gang JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    Abstract （862）      PDF（pc） （254KB）（2610）       Knowledge map    Save Abstract: This paper considers the problems of finitetime analysis and control design of nonlinear systems. Based on class K∞ functions, the more general definitions are proposed for kinds of finitetime stabilities, and the sufficient conditions are obtained by Lyapunov functions to ensure the finitetime stability of nonlinear systems. In addition, Sontag's formula is used to develop the design approaches for the finitetime stable, quasicontractively stable and disturbance rejection controllers. Related Articles | Metrics

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Optimization of emergency load shedding of receiving-end power grid based on Particle Swarm Optimization Meng LIU,Taoyang XU,Changgang LI,Yue WU,Zhi WANG,Fangfang SHI,Jianjun SU,Guohui ZHANG,Kuan LI Journal of Shandong University(Engineering Science)    2019, 49 (1): 120-128.   DOI: 10.6040/j.issn.1672-3961.0.2018.442 Abstract （1569）   HTML （6）    PDF（pc） （2721KB）（550）       Knowledge map    Save An optimization model and solving method of emergency load shedding were proposed to solve the high voltage direct current (HVDC) blocking of multi-infeed HVDC receiving-end power grid. The model was established to minimize the total amount of shed loads and was constrained by transient frequency variations, voltage variations, line overloading and load capacity of each node to maintain power system stability. The optimal variable of the model was the amount of load shedding of each node. Considering that the model was nonlinear, an adaptive parameter adjustment method based on particle swarm optimization (PSO) algorithm and parallel computing was established. The method improved the global optimization and the speed of the algorithm. Shandong Power Grid model was taken as an example to verify the validity of the algorithm for emergency load shedding following HVDC blocking. Table and Figures | Reference | Related Articles | Metrics

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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 Abstract （2319）   HTML （263）    PDF（pc） （2986KB）（1691）       Knowledge map    Save 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. Table and Figures | Reference | Related Articles | Metrics

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Simulation and optimization on ethyl acetate producing batch reactive distillation FENG Zhen-heng, ZHANG Zhong-cheng JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2010, 40 (3): 154-158.   Abstract （945）      PDF（pc） （688KB）（2691）       Knowledge map    Save To get the optimum technological condition of the preparation of ethyl acetate from acetic acid and ethanol, based on  experimental data, the experiment was simulated and optimized by using Aspen Plus, a simulation software of chemical technology using the NRTL activity coefficient model and the HaydenO′Connell equation of the gas state.The parameters of the reflux ratio, heating temperature and the feed molar ratio of ethanol to acetic acid were optimized. Under these optimized conditions,the reflux ratio was 5.1, the heating temperature was 120℃,  and the feed molar ratio of ethanol to acetic acid was 1.04∶1.00. Simulated with Aspen Plus, the mass fraction of ethyl acetate in distillate reached 82.13％. Based on these optimized conditions, the improvement on the experimental conditions, the mass fraction of ethyl acetate in the distillate  increased from   79.45％ to 81.95％,  which proved the reliability of the simulation and optimization.   Related Articles | Metrics

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Application of “sleeve-connected H-type” buffer in concrete transportation within oversize shafts LIU Xie, LI Guohua, WANG Ming, MA Chishuai JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2017, 47 (2): 37-40.   DOI: 10.6040/j.issn.1672-3961.0.2017.095 Abstract （1636）      PDF（pc） （1627KB）（1185）       Knowledge map    Save Regarding aggregate segregation, excessively fast slipping and poor concrete mix-ability during concrete long distance convey by articulated chute in surge shaft of N-J(NEELUM-JHELUM)hydroelectric project, one kind of “sleeve-connected H-type” buffer was designed and its structure design & operation principle were discussed. Comparative trial and application in site indicate that comparing with original MY·BOX buffer the new one has a simpler structure and cheaper cost, and it can effectively control the concretes dropping speed under high elevation difference and resolve the concrete segregation and damage as well as breaking through for chute, guaranteeing the service life of equipment, construction safety and quality of concrete works, which can also provide reference for similar surge shaft concrete lining project. Reference | Related Articles | Metrics

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Restrictions and countermeasures of distributed PV integration based on secondary battery energy storage system Fei WANG, Chunyi WANG, Chuanyong WANG, Guangfeng ZHAO, Mu LI, Xiaohan SHI Journal of Shandong University(Engineering Science)    2018, 48 (6): 109-115.   DOI: 10.6040/j.issn.1672-3961.0.2018.260 Abstract （1414）   HTML （6）    PDF（pc） （6513KB）（597）       Knowledge map    Save The distributed PV in rural areas was taken as object, the main factors limiting the integration of the PV generation was analyzed and the feasible solution was proposed based on secondary battery energy storage system. The weakness of distributed PV integration was analyzed from the points of view of primary equipment capacity, voltage control and fluctuation of PV output power. The investment model of grid upgrading and energy storage installation was built, based on which the economic comparison was carried out and the countermeasure based on secondary battery energy storage system was proposed. A prototype of secondary battery energy storage system adopting dynamic group theory was developed and the field test was carried out. The results demonstrated that the prototype could reduce the variance of the photovoltaic power by 35% as well as reduced the maximum peak and peak difference by 60%. The prototype could also reduce the peak and valley difference of the transformer by 20% and the load rate by 12%, which could effectively support the distribution of distributed PV. Table and Figures | Reference | Related Articles | Metrics

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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.   DOI: 10.6040/j.issn.1672-3961.0.2020.160 Abstract （1368）   HTML （166）    PDF（pc） （6369KB）（1729）       Knowledge map    Save 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. Table and Figures | Reference | Related Articles | Metrics

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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 Abstract （1026）      PDF（pc） （1618KB）（526）       Knowledge map    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. Reference | Related Articles | Metrics

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Location and algorithm of multi-level electric vehicle charging stations ZHANG Guo-liang, LI Bo*, WANG Yun-fa JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2011, 41 (6): 136-142.   Abstract （960）      PDF（pc） （1538KB）（2686）       Knowledge map    Save The charging station is  part  of the crucial infrastructure of  the electric vehicle, and the location and scale of the charging stations are  significant for the development of the electric vehicle industry. A location and solving algorithm of multi-level electric vehicle charging stations was proposed. Concerning  the user’ distributions,based on the objective program thought, the multi-level electric site model was developed to minimize the initial construction cost and the total users’ charging service cost. An improved tabu search algorithm was presented to solve the model. The new combination of tabu coding and the generating of initial solutions were  designed to characterize the two decision variables of the multi-level sites and the allocation to the users, using the strategy of 2-opt search neighbor,  locating sites,   station levels and the allocation of the demand points to the stations were simultaneously determined. Finally, a numerical example demonstrated that the algorithm had better global searching performance and convergence property and the proposed model was also effective. Related Articles | Metrics

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A survey of image captioning methods based on deep learning Zhifu CHANG,Fengyu ZHOU,Yugang WANG,Dongdong SHEN,Yang ZHAO Journal of Shandong University(Engineering Science)    2019, 49 (6): 25-35.   DOI: 10.6040/j.issn.1672-3961.0.2019.244 Abstract （4304）   HTML （121）    PDF（pc） （7881KB）（1694）       Knowledge map    Save Image captioning is the cross-research direction of computer vision and natural language processing. This paper aimsed to summarize the deep learning methods in the field of image captioning. Imgage captioning methods based on deep learning was summarized into five categories: multimodal space based method, multi-region based method, enconder-deconder based method, reinforcement learning based method, and generative adversarial networks based method.The datasets and evaluation metrics were demonstrated, and experimental result of different methods were compared. The three key problems and future research direction for image captioning were presented and summarized. Table and Figures | Reference | Related Articles | Metrics

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Review of risk conflict identification and early warning for interchange Jianqing WU,Qifeng WANG,Zhouyuan LI,Yuan TIAN Journal of Shandong University(Engineering Science)    2022, 52 (6): 1-13.   DOI: 10.6040/j.issn.1672-3961.0.2022.172 Abstract （1171）   HTML （30）    PDF（pc） （2835KB）（953）       Knowledge map    Save This review focused on three parts with data collection method, related indexes of traffic conflict and conflict risk early warning method. Each step of the technology was introduced from range of application, working principle, advantages and disadvantages.Based on the real-time multi-sensor data fusion and roadside early warning method, the future development trend and practical application of risk conflict identification and early warning technology for urban interchanges were prospected. Table and Figures | Reference | Related Articles | Metrics

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Research review of highway differentiated toll collection Jianqing WU,Yanqiang HUO,Jianzhu WANG,Hongyu GUO Journal of Shandong University(Engineering Science)    2023, 53 (4): 18-29.   DOI: 10.6040/j.issn.1672-3961.0.2023.063 Abstract （706）   HTML （20）    PDF（pc） （1386KB）（736）       Knowledge map    Save In order to formulate a scientific and reasonable scheme for highway differentiated toll collection, the background, realization manners, related theories and key technologies are systematically described, and the cases upgraded in Guangxi, Tianjin and Hebei are briefly introduced with design essentials and application effects, and outlooks on the research trend of highway differentiated toll collection are given. Table and Figures | Reference | Related Articles | Metrics

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JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE)    2009, 39 (1): 27-32.   Abstract （758）      PDF（pc） （398KB）（4565）       Knowledge map    Save Abstract: The goal of super resolution is to get high resolution images from at least one low resolution image. However, with the traditional (interpolationbased and reconstructionbased) methods it is difficult to make further important progress. The emerging learningbased superresolution methods breathe new life into the research. By reviewing these three kinds of methods, the history of super resolution was surveyed, the limitation of existing methods was discussed and the roadmap was analyzed for future developments. Related Articles | Metrics