2010 volumne 31卷 Issue 01
Xiong Ergang; LIANG Xingwen; Zhang Qian

Abstract:
The basic principle and implementation steps of the capability spectrum method are expounded, and the seismic design based on the capability spectrum method is carried out by taking a five-story steel frame structure as an example. In the seismic performance evaluation of the structure under the action of rare intensity earthquake, there is no need to perform iterative solving, and the capability spectrum curve is directly numerically simulated, and then the equation system is solved to obtain the performance points. The analysis results show that the proposed method can reflect the seismic performance of the structure more realistically, and it is intuitive and convenient. Finally, the dynamic time history analysis method is used to verify the feasibility of the proposed method, which provides a certain basis for the seismic design of steel frame structure based on the capability spectrum method.

ZHU Junfeng; ZHU Haihua; Wang Dongwei

Abstract:
Based on the interlayer displacement and interlayer deformation failure as the main failure mode, the reliability calculation of RC multilayer frame structure under small seismic action is carried out by PNET method, and compared with the results of Monte Carlo method, the research results show that it is feasible to calculate the reliability of RC multilayer frame structure with interlayer deformation failure as the main failure mode and considering the failure correlation between them.

Hu Lili; ZHENG Hong; SONG Xiaoqiang; etc

Abstract:
In order to realize the stiffness of steel structure houses can be gradually adjusted within a certain range, and improve the use range of steel structure houses in earthquake areas, a new type of seismic reinforcement system for high-rise steel structure houses is introduced: a reinforced concrete deep beam. Through the comparative experimental study of the steel frame and the pure frame filled with reinforced concrete deep beams under the action of horizontal and low-cycle repeated loading, the results show that the initial stiffness, yield load and ultimate bearing capacity of pure steel structures can be greatly improved. It can be used as the first line of defense for seismic fortification of steel structure houses. Through the appropriate simplification of the structure, an effective calculation of the synergistic analysis model between reinforced concrete deep beam and steel frame is proposed, which can be used to analyze the horizontal load borne by deep beam.

Guo Legong; Guo Lening

Abstract:
The distribution of force characteristics and horizontal loads of frame-shear wall structures is different from that of frame structures and shear wall structures, and the reasonable distribution of lateral horizontal loads borne by the frame and shear wall requires lateral stiffness analysis of the frame-shear wall structure. Based on the flexibility of the lateral shift of the structure between the frame-shear wall, the lateral stiffness analysis of the frame-shear wall structure is carried out, and a new calculation method based on the discretization distribution mode of the internal force of the chain rod is reasonably allocated to the horizontal load of the frame and the shear wall in the frame-shear wall structure, which has a clear physical concept, simple calculation and more practical application, and can be applied to the structure of flat frame-shear wall.

GUO Yuancheng; ZHAO Xuyang; Zhang Sihua

Abstract:
Aiming at the phenomenon of "disc settlement" that is common under the stiffness design conditions such as pile raft foundation, from the perspective of deformation control, the pile body at the bottom of the raft is regarded as a nonlinear spring, and the Q-s curve obtained from the single pile load test is used as the spring rate, and a simplified analysis model of pile raft foundation is established. Through numerical simulation, three design methods, planar variable stiffness, vertical variable stiffness and spatial variable stiffness, were used to reduce the differential settlement of raft foundation, and the settlement characteristics of various design methods under uniform load of pile raft foundation were compared and analyzed. The results show that the spatial stiffness of the pile raft foundation can effectively reduce the differential settlement of the foundation, improve the force deformation characteristics of the foundation, and reduce the amount of materials, and the technical and economic benefits are significant.

LIU Jianxun; Li Bo

Abstract:
Based on fractal geometry theory, the fractal distribution model of ore material is derived. Taking SUPERPAVE-19 as an example, the gradation dimension of ore is calculated, and the relationship between fractal dimension and mixture design parameters is studied through the test of asphalt mixture design parameters, and the design parameters of SUPERPAVE mixture are estimated on this basis. THE RESULTS SHOW THAT THE SUPERPAVE MIXTURE ORE GRADATION ALSO HAS OBVIOUS FRACTAL CHARACTERISTICS: THE FRACTIONAL DIMENSION D HAS A GOOD LINEAR CORRELATION WITH THE DESIGN PARAMETERS SUCH AS ORE GAP RATE, ASPHALT SATURATION, INITIAL COMPACTION DEGREE AND ASPHALT DOSAGE. USING THE FRACTAL LAW OF ORE GRADATION, THE VOLUME PARAMETERS OF SUPERPAVE MIXTURES WITH DIFFERENT DIMENSIONAL VALUES D CAN BE ESTIMATED, SO THAT THE MIXING RATIO DESIGN OF MIXTURES IS MORE TARGETED.

ZHOU Yan; Chen Jiaofa; LIU Dan; etc

Abstract:
SAMPAVE (Stress Absorbing Mixtures Pavement) asphalt mixture is a new type of stress absorbing layer material that delays and prevents reflective cracks, and has the characteristics of crack resistance, impermeability and bonding. The composition of the SAMPAVE mixture was designed according to the variable i method, and compared with AC-5, American code, and Coriolis recommended grading range. The results show that for the SAMPAVE mixture designed by the variable i method, the asphalt dosage determined by the upper and lower grading limits is within the range of ±0.3% of the design engineering graded asphalt dosage, which meets the requirements of production control, and the SAMPAVE mixture has excellent road performance such as high temperature resistance, low temperature resistance, deformation resistance, fatigue resistance and water damage resistance.

Tang Xianxi; Xu Yue

Abstract:
In order to study the reasonable thickness and height of the concrete T-beam bridge diaphragm, a 56-group concrete simple-support T beam ANSYS finite element numerical model was established, and the force performance of each group of models was analyzed with medium load and side load. The analysis results show that when the height of the diaphragm is between 54%~81% of the rib plate height, and the thickness of the diaphragm does not exceed 20 cm, the middle span deflection of the main beam, the maximum longitudinal tensile stress of the steel bar in the main beam span and the transverse tensile stress of the steel bar at the bottom of the middle plate span of the middle diaphragm have reached more suitable values. Therefore, the reasonable value of the height of the diaphragm should be between 54%~81% of the height of the rib plate, and the reasonable value of the thickness should be between 12 cm~20 cm.

LI Jingbin; CHEN Huai; Ge Sujuan

Abstract:
Taking the Zhentugou Bridge in Henan Province, which was completely replaced after the support was damaged, as the research object, the construction process simulation analysis of the four-span simple support and then continuous small box girder bridge with large longitudinal slope was carried out by using the large-scale finite element software MIDAs/Civ-il. The overall jacking scheme and the partial jacking scheme were compared, and the pier top bending moment, pier top shear force and span mid-span bending moment of the small box girder bridge under the two jacking schemes were compared. The calculation results show that the maximum lifting stroke of 2 mm of each pier support is reasonable. From the perspective of reasonable force on the superstructure of the bridge, the overall jacking scheme is better than the local jacking scheme, and the calculation results can be used as a reference for similar projects.

Ren Rui; Xie Yongli; Come to Hongpeng

Abstract:
According to the engineering characteristics of the collapsible loess foundation of the Zhengxi Passenger Line, the finite element method was used to analyze the functional characteristics of the long and short pile composite foundation under the load of the embankment in the loess area. In the analysis, the pile body and soil body were simulated by ideal elastic-plastic model, the yield criterion was based on the Druker-prager yield criterion, and the life-and-death unit technology was used to simulate the hierarchical loading of the embankment. The "stepwise indentation method" was used to study the influence of each parameter of the pile on the effect of the composite foundation of long and short piles, and the degree of influence was analyzed. The analysis results show that the effect of short piles on improving the bearing capacity of the foundation is not obvious, and it is mainly used to eliminate the collapsibility of the upper collapsible loess. Increasing the deformation modulus of long piles can effectively improve the bearing capacity of the foundation and reduce the settlement of the foundation. Therefore, for different foundation soils, optimizing the selection of long and short pile types can not only meet the treatment requirements, but also improve the economic benefits.

SUN Peiqin; Heng Xingxing; SUN Shaohui; etc

Abstract:
The direct liquefaction products of Paulownia paulownia using iron powder as catalyst in deionized water at 280~360°C were analyzed by Fourier transform infrared spectroscopy, and the effects of reaction temperature on the direct liquefaction process and heavy oil and light oil components of Paulownia biomass were investigated by comparing the infrared group differences between raw materials and residues. The results showed that with iron powder as catalyst, the reaction temperature had a significant effect on the liquefaction process, and the hemicellulose and cellulose in Paulownia were completely reacted at 320°C. Lignin degrades from 280°C, and the solid residue also contains an aromatic ring structure in the reaction temperature range. The functional group of the final liquefied product heavy oil is not greatly affected by the reaction temperature; Heavy and light oils are complex mixtures that contain various compounds such as hydrocarbons, aldehydes, ketones, carboxylic acids, phenols, and esters.

Weng Haibo; Respectfully; Yang Danli; etc

Abstract:
A strain with high protease production was identified as Bacillus subtilis and named I15 from high-temperature compost soil samples. The results showed that corn starch and soybean cake flour were the most suitable and economical sources of carbon and nitrogen for protease production by fermentation. This protease is a high-temperature alkaline protease with strong thermal stability and acid-base stability. In addition, the outstanding property is that the protease has super resistance to surfactants and mild detergents, which will have broad market prospects.

GUO Xiali; Yang Xiaoli; Li Shunyi; etc

Abstract:
Direct return of straw to the field will bring adverse effects on crop growth, and the addition of cellulose-degrading myxote in the process of returning to the field is an effective way to solve its adverse effects. Through plate preliminary screening, comprehensive determination of enzyme activity and straw degradation rate determination and re-screening, 5 high-efficiency cellulose-degrading bacteria were screened from decaying straw, cow manure compost, forest soil and other samples, among which X1 bacteria had the best enzyme activity and the most reasonable enzyme system composition, and their Cx, Cb, C1 and FPA reached 53.6 U/mL, 69.7 U/mL, 9.5 U/mL and 11.6 U/mL, respectively, and the degradation rate of straw reached 40.2%. A group of compound bacteria X1+X2 with significantly increased straw degradation rate were obtained, and the degradation rate reached 45.5%.According to the colony and individual morphological characteristics of X1 and X2, it was preliminarily determined that they were both Penicillium.

LIU Minshan; Yang Fan; Dong Qiwu; etc

Abstract:
Numerical simulation of the shell range of bow baffle heat exchanger with different structural parameters shows that the pressure drop and tube surface heat transfer coefficient of the baffle heat exchanger shell range increase with the increase of the number of baffles, and decrease with the increase of the notch height of the baffle. Its comprehensive performance decreases with the increase of the number of baffles, and increases with the increase of the notch height of the baffle. The distance between the first baffle plate and the tube sheet has little effect on the pressure drop, but relatively large on the surface heat transfer coefficient.

ZHANG Zhong—lin,CAO Zhi—yu,LI Yuan—tao
Abstract:
Euclid distance is commonly used to measure distance in the traditional k_means algorithm.The k—means algorithm based on weighted Euclid distance is researched and presented to overcome the  existing problems of similarity calculation in clustering analysis based on traditional Euclid distance when we have no any domain knowledge about the data objects,the relative distance but not absolutedistance is more accurately response to data distribution.Experiments on the standard database UCI show that the proposed method can produce a high accuracy clustering result.
ZHANG Zhonglin; Cao Zhiyu; Li Yuantao

Abstract:
Traditional k_means algorithms use Euclidean distance as the most commonly used distance measurement method. Aiming at the shortcomings of calculating the similarity between sample points and classes based on Euclidean distance, replacing "absolute distance" with "relative distance" can better reflect the actual distribution of samples, and a k_means algorithm based on weighted Euclidean distance is proposed when the domain knowledge is unknown. Experiments on the data in the public database UCI show that the improved algorithm can produce high-quality clustering results.

ZHANG Duanjin; ZHANG Zhonghua; GUO Jianjun; etc

Abstract:
Aiming at the delay estimation problem in radiopositioning, considering that the received signal is a narrowband signal and the background noise is Gaussian distribution, a new delay estimation method is presented by taking the one-dimensional slice of the fourth-order cumulative quantity as a higher-order statistic, combined with the Hilbert transform. This method sharpens the relevant peaks and improves the estimation accuracy. Compared with the generalized cross-correlation method, the algorithm can effectively suppress the influence of space-related Gaussian noise, and the calculation amount is small and easy to implement. The simulation results show the effectiveness of the proposed method.

Li Canbing; Qu Fang; WANG Xiaoning; etc

Abstract:
Taking the substation load composition ratio as the basic feature vector, the fuzzy clustering method of adaptive vector quantization (AVQ) neural network is proposed to classify and synthesize the power load characteristics. The fuzzy clustering method of AVQ neural network and the fuzzy C-mean (FCM) concubine method were compared. Through the cluster analysis of 44 substations of Fujian Power Grid, it is concluded that the two clustering methods not only have good clustering comprehensive ability, but also can obtain the clustering center matrix through optimization theory, which has obvious advantages compared with other clustering methods. Compared with the two, the AVQ neural network fuzzy clustering algorithm itself is small, the processing speed is faster, and the results are more reasonable.

SONG Tao; Liu Gang

Abstract:
Using an image as the query retrieval input, the image is retrieved according to the similarity between the layout analysis features, statistical features, and texture features of the image and the image in the database. Firstly, the mathematical morphology is used to segment and line segmentation of document images, which are used as the layout structure characteristics of document images. Then, according to the statistical characteristics of the image, including the number of characters, statistical features, and texture features, the document image extraction algorithm is given. Finally, the retrieval algorithm model is given. Experimental results show that the proposed algorithm has good accuracy and recall rate, and has application value in content-based document image retrieval.

ZHANG Jian; SUN Jia; Zheng Wenqi; etc

Abstract:
An electric energy prepayment system is introduced, which is mainly used for three-phase power users. The pre-bamboo fee controller terminal and the energy meter are separated by reading relevant data from the original meter for comparison, and the prepaid control system is installed with as little change as possible to the original wiring. Using RFID card with high security and stability, large data storage space, and realizes non-open-the-box operation. The controller terminal data storage adopts data redundancy technology to effectively reduce the possibility of data loss and errors. The background management system is embedded with a power quality management program to analyze the relevant parameter data read from the meter and improve the quality of power supply; Add user credit management to realize credit management. The background management system and the controller terminal are combined to realize the loss of card without losing power, and fully protect the rights and interests of users. The system can be upgraded, and user accounts can be added to achieve one card and multiple households or one table multiple cards. The introduction of anti-theft thinking of unpacking records can realize unpacking management and prevent electricity theft.

Copyright © 2023 Editorial Board of Journal of Zhengzhou University (Engineering Science)