2019 volumne 40卷 Issue 03
JI Young,LIU Dandan,LUO Yong,WANG Pengshuai
Abstract: undefined
Based on Hough voting method, the recognizing of substation equipment was achived by using 3Dcloud data obtained by laser scanner. Firstly,the equipment point cloud data was preprocessed to obtain appropriate experimental data, including point cloud simplifying and denoising by octree. Secondly, thenumber of votes of the mass center of the point cloud was got by Hough voting after obtaining DSM. Thirdlysimilarity degrees could be got by comparing the DSM with any model DSM in model set, and initial identification results could be obtained by comparing the above similarity degrees with the threshold. Lastly, the finaldentification result was got by Hough voting based on initial identification result. The actual test showed thatthis method could effectively avoid the lengthy searching process for all feature points, and could be effectivein recognizing of substation equipment in the situation of a larger points lacking. It turned out that this method was effective.

Guo Yinan 1,Cheng Wei 1,Yang Huan 1,Yang Fan 1,2,Lu hope 1
Abstract: As the key equipment of tunneling a roadway, controlling the anchor-hole drills mainly depends on the operator’s experience. Improper rotary speed of an anchor-hole drill generally results in sticking or breaking pipes, which reduces the drilling efficiency. Especially, the nonlinearities and time-varying parameters, as well as the disturbances resulted from various factors in the anchor-hole drill rotary system shall be taken into consideration. A novel optimal active-disturbance-rejection controller is proposed in the paper. The set value of the rotary speed is dynamically estimated in terms of the geological condition of surrounding rocks. Brain storm optimization algorithm is employed to find the optimal parameters of the controller, which have the best dynamic and steady control performances. Based on the simulation platform composed of AMESim and Matlab, the experimental results for a single surrounding rock with or without the external disturbance show that the proposed ADRC controller has better dynamic and steady performances and stronger robustness than the optimal PID controller.
Hao Wei,Lin Huiyi,Hao Wangshen,Gao Yajuan,Dong Xinmin
Abstract: Aiming at the feature shift phenomenon when using time domain signals to sparse coding and the problem of single channel analysis often result in inadequate use of information, a new method for fault identification of rolling bearings is proposed by combining the full vector spectrum technique and sparse coding. Firstly, full vector information fusion of the homogeneous dual-channel signal of the rolling bearing in each state is carried out. Then, the main vibration vector signals obtained is used to construct all kinds of redundant dictionaries. Finally, these dictionaries is used to reconstruct the test samples, and the error is used as the basis for identify the status of these samples. The method use the main vibration vector signals obtained by full vector fusion as training samples, so the training samples contain more comprehensive and accurate information. Besides, the feature extraction step can be eliminated, so it can reduce the effect of human factors. The experimental results show that the method has high efficiency and good stability, and can effectively identify the fault pattern of rolling bearing.
Wang Jie,Wang Yubo,Zhu Xiaodong,Ren Xiangyang
Abstract: Blocking artifacts are the result of block-based discrete cosine transform in JPEG coding .An efficient no-reference method to measure the blocking artifacts is proposed in this paper. Firstly, the gradient of the pixels at block boundaries is transformed into the blocking artifact map ,which mainly includes the positions and intensity information of blocking artifact boundaries. Then We computer the effects of luminance and texture masking on blocking and integrate them into the blocking artifact map to form an noticeable blocking artifacts map. Based on the noticeable blocking artifacts map, we use the Minkowski method to calculate the metric of image blocking artifacts. Finally experiments for several image quality assessment databases showed that the proposed metric provides high monotonous consistency with subjective blockiness scores and outperforms other existing mainstream blockiness metrics
Chen WeihangZhang HuiZhang Jie
Abstract: Antioxidant performance of polymeric procyanidins was significantly less than oligomers, and not easily absorbed by the body. The research is devoted to the preparation of SO42- / TiO2 solid acid catalyst with excellent performance, and the solid acid is used to degrade procyanidins in lotus-shaped medium. Degradation of Polymeric Procyanidins was analyzed by UV spectrophotometer and gel chromatography. The degradation degree was evaluated by the average polymeric degree and degradation rate. Under the reaction conditions of 10 ml of the solution of proanthocyanidin as degradation raw material, when the addition of solid acid was 0.05g, the reaction temperature was 70 ℃ and the reaction time was 60min , the results showed that the average polymerization degree of the polymer decreased from 5.95 to 2.31 and the degradation rate can reach 61.18%
Zhang Xiang,Feng Xiu,Zhi Hongtao,Ma Nannan,Han Shuangqiao
Abstract: :A new kind of four-group coordination agent tetra(dithiocarbamate)dipiperazine (TDDP) was synthesized in this article, and the effect of TDDP as a capturing agent on low concentration heavy metal wastewater was investigated.The experimental results showed that dosage of TDDP in 1.2:1 stoichiometric amounts could reduce free Cu2+,Pb2+,Zn2+from 10mg/L to 0.35mg/L,0.39mg/L,0.89mg/L;and TDDP can be used in wide pH range, the removal efficiency was basically not influenced by pH of 4~11.Besides TDDP was selective for removing heavy metal ions,the chelating ability of TDDP for heavy metal ions is Cu2+>Pb2+>Zn2+>Cd2+ in acidic condition
Wu Xiaoguang,He Pan,He Qilong,Feng Yu
Abstract: In order to establish the measured temperature gradient field of continuous box girder bridges in different areas of Shaanxi Province, three representative continuous girder bridges in northern Shaanxi, central Shaanxi and southern Shaanxi were selected for one year continuous observation. By fitting the measured temperature data, three temperature gradient models have been established. The results show that the vertical maximum temperature difference of continuous box girder bridge in three areas in Shaanxi Province is different. According to the specifications set concrete pavement, the maximum temperature of northern region is 18.6℃, the maximum temperature of central Shaanxi is 21.2℃, the maximum temperature of southern Shaanxi is 22.9℃, but were less than the standard value of 25℃. Different from the normative provisions, the measured data show that there is vertical temperature difference in the bottom plate of the box girder, the maximum positive and negative temperature differences of the bottom plate in the three regions were 3.5℃ (-3.1℃), 2.8℃ (-2.9℃) and 1.5℃ (-1.5℃). Based on the measured temperature gradient, the finite element model of the box girder closure section was established, and the measured temperature effect was analysed. The results showed that in the positive temperature gradient , without considering the vertical temperature gradient effect of the bottom plate, it is partial safety; in the negative temperature gradient, not taking into account the effect of vertical temperature gradient of the bottom plate, the force would have a negative impact for bottom plate, impartial security. It is suggested that the vertical temperature gradient of the bottom plate should be considered comprehensively in the design checking of continuous (rigid frame) box girder bridge
Li Nana 1,Huang Kunqiang 2,Zhang Qiuwen 1,Liu Kuan 1
Abstract: In order to solve the problem of high complexity of HEVC coding, an efficient adaptive quantizer selection and rate distortion optimized quantization decision algorithm is proposed in this paper. The quantizer determines whether the quantization level of the transform coefficient is equal or zero and whether the sum of quantization levels is less than the set threshold.If the quantization level is equal or zero, the traditional RDOQ is used directly.Otherwise, a threshold decision is made,and finally determine the optimal quantizer.The proposed decision algorithm can select two quantization methods: Uniform Scalar Quantizer with small computational complexity and RDOQ with low bit rate self-adaptively, and the computational complexity of the encoder is reduced.The experimental results shows that our proposed algorithm can save about 10.52% of coding time.
Mu Xiaomin,Xu Ruru,Zhang Songwei,Han Gangtao
Abstract: In the article, the problem that demand-aware multichannel opportunistic spectrum access in cognitive radio networks is researched and users’ satisfaction function is defined to measure users’ satisfaction effect, and an optimization problem in channel selection based on game theory is constructed. Interference constraint was drawn in the definition of users’ income function, aiming at giving consideration to both sides between minimizing users’interference and maximizing users’ satisfaction, and improve network per-formance at the same time. In this paper, It is verified that the game is an accurate potential game with at least one pure strategy Nash equilibrium and the Nash equilibrium is the optimal solution of the above optimization problem, and finally the simulation results are given to verify theoretical analysis is correct. It is shown that taking the satisfaction and the interference into account simultaneously can reduce the total interference of the whole network remarkably, get higher user satisfaction and the best fairness as well, and can improve the overall performance of the system.
Wu Qing 1,Zhang Chunjiang 2,Gao Liang 3
Abstract: Economic load dispatch is an important problem in power system. Some constraints exist in this problem. In literatures, penalty function methods were usually used. However, it is difficult to set proper penalty coefficients. Feasibility rules and constraint method are two popular constraint handling techniques. However, they are not efficient for economic load dispatch problem. A constraint handling method which transforms the load balance constraint to two boundary constraints is proposed in this paper. Combined with feasibility rules and constraint method, a basic differential evolution is used to solve this problem. Two classic instances are tested. The results show the proposed algorithm obtains better solutions than other compared algorithms in literatures.
Zhang Jie 1,Chen Chuang 1,Zhou Guoli 1,Wang Jingtao 1,Zheng Mengxin 2
Abstract: Herein, graphene oxide (GO) was synthesized through the improved Hummers method, and then phosphoric acid was intercalated into the interlayers to fabricate phosphoric acid intercalated graphene oxide (PGO). GO and PGO were incorporated into sulfonated poly(ether ether ketone) (SPEEK) matrix to prepare composite membranes through solution casting method. The physicochemical property and proton conduction property of composite membranes were investigated in detail. The results suggested that all the membranes were thermally stable up to 290℃. Under anhydrous condition, the PGO formed highly efficient transfer channels in composite membrane, which significantly enhanced the proton conduction property of membrane. Particularly, the proton conductivity of SPEEK/PGO-50 reached 7.92 mS• cm-1 at 150℃, which was 5.7 times of that of SPEEK control membrane and 4.6 times of that of SPEEK/GO.
Ding Zhan 1,Jiang Xiuming 2,Zhao Junkai 1,Li Peilong 2,Chen Chong 2
Abstract: To investigate the influencing factors of viscosity and viscous flow properties of rubber asphalt, rubber asphalt (RA) samples were prepared under different conditions of mixing temperature and processing time for different rubber dosage. Brookfield viscosity tests were carried out on RA samples, and the effect of these factors on viscosity of RA was analyzed. The visco-flow activation energy(Eη)of RA was calculated using Arrhenius equation according to the viscosity values of asphalt under different temperatures. The changing regularity of Eη was analyzed. The results and analysis indicate that the viscosity values of RA increase by the exponential growth model continuously with the increase of rubber content. There is a certain equivalence for rubber asphalt viscosity between raising mixing temperature and extending the processing time. But too high temperature or too much time may lead to excessive degradation of rubber molecules, which will cause the decrease of RA viscosity. With the increase in the dosage of crumb rubber, Eη of RA for origin or aged samples both goes up first and then drops down. And peak Eη exists in the range of rubber content from 10% to 15%. The Eη value of aged RA is bigger than that of original sample for the same rubber dosage. From the consideration of viscosity factors and viscous flow properties, the processing conditions are recommended that the dosage of crumb rubber is 15%~25%, preparation temperature is 180 ℃ and the processing time is 90 min approximately based on this research.
Liu Zhongzhu 1,Qin Qi 1,Li Suishui 2,Zheng Guoqiang 2,Mi Liwei 1
Abstract: The rare earth β-nucleating agent modified isotactic polypropylene (iPP) films were prepared by melt extrusion-stretching method. Subsequently, the films were heated to different fusion temperatures. The influence of ordered melt structures on non-isothermal and isothermal crystallization behavior of β-iPP films were investigated by DSC and POM experiments. The results indicated that, during the non-isothermal crystallization process, the partially melted β-iPP can induce the formation of more nucleation sites with decreasing crystallization temperature, and then inducing the crystallization at higher temperature; Meanwhile, the dense cylindrite is formed in samples. During the isothermal crystallization process, when the Tf is below 169 °C, the β crystal is transformed into α crystal in the sample; however, when the Tf is above 169 °C, the α crystal in the sample gradually changes into the β crystal.
Zhang Huiling,Yang Linyu,Ao Guchang
Abstract: Signalized intersection delay is closely related to vehicles. Research on the first vehicle arrival during red light is contribute to better analysis of influence factors of delay at signalized intersections, thus contribute to better intersection signal control design to improve the level of service. Firstly, The paper analyzes feature of the first vehicle arrival base on time difference between stopping time of the first car arriving at the stop line during the red light and the start of Red time,. And then the paper studier intersection of a straight line approach and puts more detailed studies on the factors affecting the vehicle arrives at signalized intersection. The 6 factors and 5 levels are chosen considering the possible impacting factors. The orthogonal experiment is used to get the experiments’ combination, and the VISSIM software is used to get the experiment scene. Based on the simulation model, the order of the factors impacting the first vehicle arrival during red light is the saturation, types of vehicles arrival, intersection spacing, the split, the saturated flow, the bus ratio. Finally For the interaction phenomenon of saturated flow and saturation, using transactional analysis to learn that: when saturated flow is 1650pcu/the green light for hours, and saturation is 0.25, there is the highest level of impact on the vehicles.
Zhao Lijun 1,Shen Yan 1,Deng Xin 1,Liu Benxue 2,Dong Wu 1,Li Yao 1
Abstract: In order to improve mixing uniformity of asphalt mixture, the EDEM software based on discrete element method was used to simulate the mixing process of asphalt mixture with different mixing blade parameters. The influence on mixing uniformity and matching relationship of total number of single shaft blades, blade arrangement on single shaft, shaft angle of the blade and the number of reversing blade were determined by orthogonal analysis of the mixing time required to reach given uniformity of variation coefficient of filler content from different location in the same batch, and test verification was conducted. The results show that the variation coefficient of filler content with different mixing parameters was decreased with increase of mixing time, and the relationship between them is a negative power function. For the given uniformity of variation coefficient of filler content of 0.06, mixing time of different mixing blade parameters is about 25~35s, the maximum difference is 30%. The effect of total number of single shaft blades on mixing uniformity is the most significant, blade arrangement on the single shaft and shaft angle of the blade are the second, the number of reversing blade is the least. Under the same conditions of the capacity of mixer and blade geometrical size, the effect of improving mixing uniformity is the most remarkable by reducing the total number of single shaft blades and consequently, the length-width ratio of the mixer will be within 1. And on this basis, the other blade parameters are matched: the blades are arranged symmetrically on both sides of one shaft, the shaft angle is 45°, the number of reversing blade is 2. As far as possible to speed up the intensity and frequency of materials circular motion in mixer is the main basis for selecting and matching parameters of the mixing blade.
Jiang Yang1,Guo Jiankun 1,Wang Xiaomou 2,Hou Chaoqun 3
Abstract:  In the field of engineering construction, foundations were often placed adjacent to slopes. In the present research work, the evaluation of the maximum bearing capacity of slope foundations lacked a sufficientrate method. A bilateral asymmetry slip failure model for ground foundation adjacent to slope was develthe strength of soil on the side of flat ground was reduced and this is characterized by a mobilization factor. Base on limit equilibrium method and superposition principle, three bearing capacity factors were ex-pressed. The upper bound bearing capacity for ground foundation adjacent to slope was deduced based on limitanalysis approach. Centrifugal model tests were used to verify the theoretical analysis results; and thetion and failure characteristics of these foundations were studied. In addition the influence of variousuch as the contact conditions of the foundation, the location of the foundation, and the height of slope on themaximum bearing capacity of these foundation

Li Yilin,Huang Xuqin,Wu Xiaoguang
Abstract: Continuous rigid frame bridges with high piers mostly use hollow thin-walled pier, and the bottom of the piers should have appropriate solid sections in order to ensure the stiffness transition of the cap and thin-wall pier. At present, there is no literature to research the design length of solid section, and the design is based on engineering experiences to select, which has great limitations. In this paper, the transfer length of the solid section is first time analyzed by calculating the anti-push rigidity of bridge in axial direction of the single thin-wall pier in the hollow section and the solid section, and the constraint effect at the connection point between the hollow section and the solid section is simulated by exerting the translational constraint, the rotational constraint and the flat rotation coupling constraint springs. Finally, engineering examples are given to verify the correctness and applicability of the analysis thought and derivation process. In this paper, the research conclusions suggest that the solid section at the bottom of the piers’ calculation length range can take 3-6m, and can be written into the specification to guide the design and construction of the high piers.
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