Journal of Northeastern University(Natural Science)

Interval Multi-objective Particle Swarm Optimization Algorithm and Its Application

GUAN Shou-ping， ZOU Li-fu， ZHANG Jing-jing

2019, 40 (11): 1521-1526. DOI: 10.12068/j.issn.1005-3026.2019.11.001

Abstract ( 978 )

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An interval multi-objective particle swarm optimization(IMOPSO)algorithm was proposed to solve the optimization problem of interval variables under multi-objectives. A dominant relationship between two intervals was defined based on interval credibility. Normalization method and interval crowding distance were used to sort the Pareto-optimal solutions. And an archiving mechanism was set up to save the Pareto optimal set in the external memory. Then， an interval neural network(INN)employing the IMOPSO to train was proposed for the unknown-but-bounded(UBB)errors modeling problem， which can be suited for the two situations of the error bounds that is either known or unknown. The first-order uncertain system was taken as an example to verify the proposed method， and the simulation results validated the effectiveness.

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Auto-Encoder for Collaborative Filtering Based on Side-Information Enhancement

LIU Hai-bo， FENG Shi， YU Ge

2019, 40 (11): 1527-1532. DOI: 10.12068/j.issn.1005-3026.2019.11.002

Abstract ( 687 )

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In view of inaccurate rating prediction of traditional recommendation model， a model based on side-information enhanced collaborative filtering auto-encoder was proposed， and the design principle， loss function and structure of the model were discussed in detail. The model was implemented by a single hidden layer auto-encoder network with ratings and side-information as input/output data. The model was directly trained by ratings and side-information. The proposed framework not only reduces the scale and complexity of the model， but also amends the user’s interest with side-information. At the same time， the representation ability of the trained model is increased by reasonable division and expansion of training datasets. The comparisons on real datasets show that the proposed model with side-information can effectively ameliorate the user’s interest predicted by the model without side-information， and improve the accuracy of rating prediction， which has a certain practicality.

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Social Network Event Recommendation Algorithms Based on User Similarity Random Walk

MA Tie-min， ZHOU Fu-cai， WANG Shuang

2019, 40 (11): 1533-1538. DOI: 10.12068/j.issn.1005-3026.2019.11.003

Abstract ( 757 )

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Aimed at the problem of insufficient coverage and accuracy of event recommendation based on social network， a user similarity-based Si-user Walker algorithm was proposed. The algorithm abstracts online user group data into graphs through event-based social network features and changes the traditional strategy of random walk based on graph-based topology structure on the basis of restart random walk algorithm. According to geographical location， event types were divided and a new calculation method of user similarity was proposed. Then， the user similarity matrix works as transition probability of random walk. Transfer probability not only preserves the transitivity of graph， but also guarantees the authenticity of graph node walk. Compared with other recommendation algorithms， it is shown that the proposed algorithm experiments on real data sets can improve root mean square error， accuracy and coverage.

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Automatic Detection Method of Paroxysmal Atrial Fibrillation for Ballistocardiagram Based on CNN

JIANG Fang-fang， XU Jing-ao， LI Ren， XU Li-sheng

2019, 40 (11): 1539-1543. DOI: 10.12068/j.issn.1005-3026.2019.11.004

Abstract ( 768 )

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Paroxysmal atrial fibrillation(PAF)is characterized by sudden onset and short duration， at present， electrocardiogram(ECG)is applied as the clinical diagnosis method， which is inconvenient for daily monitoring. Therefore， a noninvasive atrial fibrillation automatic detection method based on ballistocardiogram(BCG)was proposed. The optimal structure of one-dimensional convolutional neural network(CNN)for detecting PAF is achieved via matching different input data lengths and network depths. Through the test of 2000 sets of data， the best performances of the model proposed are: a test accuracy rate of 94.8%， a sensitivity of 97.2%， and a specificity of 92.7%， which provides the possibility of arrhythmia detection and remote daily home monitoring from BCG.

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A Novel Similarity Verification Algorithm Under Edit Distance Limitation

YU Chang-yong， LI Miao-miao， ZHAO Chu， MA Hai-tao

2019, 40 (11): 1543-1548. DOI: 10.12068/j.issn.1005-3026.2019.11.005

Abstract ( 531 )

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For the high complexity problem of edit distance calculation in the similarity confirmation step， a string similarity confirmation algorithm based on pigonhole principle under the limitation of edit distance is proposed. Firstly， it found a segment satisfies the edit distance segment mapping， then based on this segment， the read length of 500bp was segmented. Then the edit distance of right and left parts was calculated and all parts sum to the final result. Finally， based on the longest common substring， the number of segments to be verified is minimized， and an optimization scheme was obtained. The experimental result show that this verification algorithm reduces the time of the verification step， and ensures the zero false positive and false negative rate.

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Communication Method of Underwater Acoustic Sensor Network Based on Compressed Sensing

LIU Jing-hao， DONG Li-shuang， FU Xiao-mei

2019, 40 (11): 1549-1554. DOI: 10.12068/j.issn.1005-3026.2019.11.006

Abstract ( 694 )

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Current research mainly focuses on the case that a single sensor node sends data， and the transmission efficiency is low. Using multiple sensor nodes to send data at the same time can improve the transmission efficiency， but there is interference between user’s data. Compressed sensing(CS)theory is applied to underwater acoustic sensor networks. A large-capacity cooperative communication method was proposed to realize simultaneous transmission of data by multiple nodes. Using the sparse characteristics of sensor nodes， simultaneous transmission of data from multiple source nodes is equivalent to the measurement process in CS. It is proved that the transmission characteristics of multiple nodes can satisfy the restricted isometry property(RIP)in the CS theory. The destination node can recover the data of multiple concurrent sensor nodes by the reconstruction algorithm.

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Low Signal to Noise Ratio Radar Signal Sorting Algorithm Based on FastICA

WANG Bin， GAO Bing， GU Pei-shang， XIN Feng-ming

2019, 40 (11): 1555-1560. DOI: 10.12068/j.issn.1005-3026.2019.11.007

Abstract ( 724 )

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The traditional parameter-based signal sorting system cannot adapt to the problem of radar signal sorting in the current complex situation， and the blind source separation algorithm based on independent component analysis(ICA)is introduced into the radar signal sorting algorithm. FastICA algorithm combines fixed-point iteration and non-Gaussian maximization algorithm. It has the advantages of good stability， fast convergence and small calculation. However， this algorithm is very sensitive to noise and cannot be performed with low SNR. Aiming at this shortcoming， a synchronous cumulative average noise reduction algorithm is introduced， and signal equalization and smoothing to improve the original algorithm are combined， so that the new algorithm can sort the radar signals with low SNR. Simulation results show that the improved algorithm can achieve good sorting effect under low SNR and retain the advantages of the original algorithm.

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Effect of QT Treatment on Microstructure and Obdurability of a B-Nb Low Carbon Bainite Steel

REN Jia-kuan， YAN Dong， CHEN Jun， LIU Zhen-yu

2019, 40 (11): 1561-1567. DOI: 10.12068/j.issn.1005-3026.2019.11.008

Abstract ( 789 )

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Effects of QT (quenching+tempering) treatment on the proportion of grain boundary， grain size， carbide precipitation， strength and toughness of the tested steels were studied by room-temperature tensile test， pendulum impact test， optical and scanning electron microscopy， and the distribution and combination of the variants were also analyzed. The results show that when the tempering temperature increases， the strength of the tested steels gradually decreases with an increase of plasticity. The fracture modes of 450T and 500T steels are quasi-cleavage fracture， where the impact toughness becomes worse due to the carbides precipitated from bainite laths and the smaller proportion of high-angle grain boundary. The fracture modes of 600T and 650T steels are dimple fracture， where the increased proportion of the high-angle grain boundary hinders the crack propagation more effectively. The variant analysis shows that the variant combination mode of 450T steel is between Bain group and CP (close-packed) group， while that of 600T one tends to be a CP combination mode. The larger misorientation between the variants in the same CP group can deflect the path of crack propagation， which improves the low-temperature toughness.

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Study on Seawater Corrosion Resistant Ferrite Matrix High-Ti Steel

WENG Lei， WU Hong-yan， LAN Liang-yun， DU Lin-xiu

2019, 40 (11): 1568-1573. DOI: 10.12068/j.issn.1005-3026.2019.11.009

Abstract ( 648 )

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Two new types of seawater corrosion resistant steels have been developed， which contain different Ti contents. The ferrite matrix was obtained by rolling- and cooling-controlled processing. The corrosion rate of the tested steel was measured from the experiment of simulated seawater drying-wetting cycles corrosion. The corrosion morphology， composition of corrosion products and element distribution in the cross section were studied by SEM， XRD and electron probe microanalysis (EPMA). The results show that both seawater corrosion resistant steels are covered with uniform and defect-free corrosion products after the test of simulated accelerated seawater corrosion. There are a large number of the continuous Ti-rich areas formed in the inner rust layer， which can hinder the further corrosion and improve the corrosion resistance. Furthermore， the synergistic effect of Ti and P elements in the steels can also increases the ability of corrosion resistance to seawater.

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Interfacial Reaction and Strengthening Mechanism of Cu/Al Composite Strip Produced by Asymmetrical Rolling

CHANG Dong-xu， WANG Ping， ZHAO Ying-ying

2019, 40 (11): 1574-1579. DOI: 10.12068/j.issn.1005-3026.2019.11.010

Abstract ( 716 )

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The symmetrical and asymmetrical rolling process was used to produce Cu/Al composite strip. Interfacial reaction during annealing and strengthening mechanism after asymmetrical rolling were investigated. The interfacial microstructure and fracture morphology of tensile test were obtained by scanning electrical microscope. The distribution of interfacial elements was analyzed by line scanning and electron microprobe analysis. The interfacial phases were analyzed by XRD. The peeling and tensile tests were carried out to study mechanical properties of the composite strips. The results indicate that the diffusion layer with three sublayers forms after annealed at 400℃ for 1h. There is a sudden change of element content in each sublayer. A large amount of copper and the CuAl₂， Cu₉Al₄， CuAl and Cu₄Al phases are detected on the Al peeled surface， while only the Cu₉Al₄ and Cu₄Al phases are detected on the Cu peeled one. Therefore， the asymmetrical rolling bonding can improve the interfacial strength and tensile property of the composite strip and reduce the damage of interfacial interlayer from the failure.

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Influence of the Granule Morphology of MgO Particles on the Yield of Pyrolysis Products

LYU Chao， NIU Li-ping， ZHAO Qiu-yue， WANG Wen-bo

2019, 40 (11): 1579-1583. DOI: 10.12068/j.issn.1005-3026.2019.11.011

Abstract ( 611 )

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The MgO particles prepared by pyrolysis process possess different morphologies and uneven size distribution of the particles. There are some errors from the traditional numerical simulations to the experimental results， where the particles assume to be the standard spherical and same-sized particles. Therefore， an extension factor (α)， fullness factor (k) and shrinkage ratio (β) are introduced to characterize the distributions of several specific types of irregular MgO particles inside a jet-flow pyrolysis reactor. All three parameters are found to affect the yield of MgO particles greatly. When the parameters of α， k and β are -0.25， 1 and 1， respectively， the yield is maximum with a value of 96.88%， while it becomes a lower one of 80.39%， corresponding to α=0.25， k=2 and β=1.5.

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Dynamic Reliability Analysis of Mechanical Parts Under Actual Operation Conditions

YANG Zhou， JIANG Hong-meng， ZHANG Yi-min， JIANG Chao

2019, 40 (11): 1584-1589. DOI: 10.12068/j.issn.1005-3026.2019.11.012

Abstract ( 737 )

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The fatigue life of the parts were estimated by using the Goodman linear correction method and the linear cumulative damage rule， and the working load was statistically analyzed by the rain flow count method， considering the impact of the load change and the strength degradation on the reliability of mechanical parts. Then， the gradient reliability mathematical model was set up with maximum load in equal time to replace the variable load by using Gamma random process simulating strength degradation. Finally， the expression of reliability sensitivity was derived by stochastic perturbation theory and four rank moment method. The torque shaft of coal mining machine was taken as an example， the fatigue life of the shaft under actual load was estimated and the each parameter variables′ variation rule of dynamic reliability sensitivity during the fatigue life was given. Furthermore， the influence of the parameter variables′ variation on torque shaft reliability was analyzed， and the Monte Carlo simulation method was used to verify the results. All analysis results show that the dynamic reliability analysis process adopted conforms actual working conditions， and can provide a method for dynamic reliability analysis of mechanical parts in real situations.

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Numerical Simulation Research of Ultrasonic Micro-forging Assisted Laser-Wire Additive Manufacturing

REN Zhao-hui， LIU Zhen， ZHANG Xiao-shuang， ZHANG Xing-wen

2019, 40 (11): 1590-1595. DOI: 10.12068/j.issn.1005-3026.2019.11.013

Abstract ( 908 )

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Laser-wire additive manufacturing technology can greatly improve manufacturing efficiency， but the complex residual stress is existent inside the part and leads to poor internal defects. To solve these problems， ultrasonic micro-forging and rolling assistant technology were adopted， that the surface of the part is stroked with high-frequency vibration， which causes the surface of metallic material to plastically deform and the stress changes from the tensile stress to compression stress. Taking the TC4 as study object， the numerical analysis of thermal-structural coupling of laser fuse process is implemented by utilizing ANSYS， and the ultrasonic rolling micro-forging is applied to study the stress field before and after micro-forging. The results show that the stress distribution of laser fuse cladding layer， namely the stress distribution becomes more uniform， the tensile stress decreases and even transfers to compressive stress， which can effectively restrain the formation of internal defects.

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Influence of Operating Parameters on the Ejector Performance Based on CFD Simulation

HAN Yu， GUO Li-xin， WANG Xiao-dong， ZHANG Guang-li

2019, 40 (11): 1595-1599. DOI: 10.12068/j.issn.1005-3026.2019.11.014

Abstract ( 705 )

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The influences of the different operating parameters on flow characteristic of internal flow field and the ejector performance are discussed by CFD method. With the increase of the primary fluid pressure， the flow area of the secondary fluid pressure decreases at the choking position， however， the Mach number and the entrainment ratio both gradually increased， and the pumping performance is enhanced. When the pressure is too high， the flow region of the secondary fluid is compressed due to the increase of the expansion core and the entrainment ratio decreases obviously. With the increasing of the primary fluid pressure， the choking position and the shock wave moves downstream. The pumping performance of the ejector is strengthened. The entrainment ratio decreases with the increase of the back pressure. When the back pressure is too high， the reflux phenomenon is obvious and the pumping performance decreases sharply until it loses efficiency. The results indicated that the reasonable selection of the operating parameters can not only improve the pumping efficiency and exhaust capacity of the ejector， but also greatly improve the refrigeration efficiency of jet refrigeration system and reduce the energy consumption.

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Design of Distortion Similar Model for Thin-Walled Conical Shell and Method for Determining Geometric Interval

LUO Zhong， ZHANG Yong-qiang， ZHU Yun-peng， LI Chao-shuai

2019, 40 (11): 1600-1605. DOI: 10.12068/j.issn.1005-3026.2019.11.015

Abstract ( 468 )

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The distortion similarity relation of thin-walled conical shells was established by using the natural frequency of transition model based on least square method， aiming at the limitation of traditional similarity model design method， dimension analysis method and equation analysis method in some cases， a method for determining the applicable interval of distortion model was also proposed. The boundary equation of the applicable interval of geometric structure of a single material thin-walled conical shell with similar distortion model of different orders was obtained by polynomial fitting method， based on the method for determining the applicable interval of distortion model size when the model and prototype are similar in natural characteristics (natural frequencies are proportional mapping relationship， and mode shapes are consistent). The accuracy of derivation of distortion similarity relation is proved by experiment verification， which provides theoretical basis for dynamic similarity of thin-walled conical shell structure test model.

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Oncoids and Its Significance from the Base of Huanglong Formation in Langping， Guangxi

HUANG Wen-tao， GONG En-pu， ZHANG Yong-li， MIAO Zhuo-wei

2019, 40 (11): 1606-1610. DOI: 10.12068/j.issn.1005-3026.2019.11.016

Abstract ( 787 )

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The Carboniferous strata completely outcrops in Langping area， Guangxi. Oncoid-bioclastic limestone develops at the base of Huanglong Formation. To reveal the depositional environment and geological significance of the oncoids， the studies relating to paleontology， sedimentology， and petrography were carried out. The fusulinids in oncoid-bioclastic limestone establish an earliest Moscovian age， which corresponds to Profusulinella aljutovica-Taitzehoella taitzehoensis extensa subzone in South China. Four oncoid types have been recognized: micrite oncoid， debris envelope oncoid， algae envelope oncoid， and composite oncoid. Four microfacies types have been identified: MF1， MF2， MF3， and MF4. In the earliest Moscovian， the sea level started to rise， which changed the depositional environment， providing the basis for microbial activity and high water energy for the formation of oncoids in the study area.

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Study on Process Mineralogy of a High-Iron Red Mud from Shandong Province

LIU Xiao， GAO Peng， HAN Yue-xin， YING Ping

2019, 40 (11): 1611-1616. DOI: 10.12068/j.issn.1005-3026.2019.11.017

Abstract ( 807 )

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A detailed study on a high-iron red mud from Shandong province in the perspective of process mineralogy were conducted through chemical analysis， XRD， optical microscope， laser particle size analysis， energy spectrum analysis and BPMA automatic analyzer. The results show that the red mud has a fine particle size， and the chemical composition and mineral(phase)composition are complex.The main minerals(phases)in red mud are particulate silicon slag， hematite， iron-aluminum oxide， limonite， as well as trace amounts of sodium aluminosilicate， iron-titanium oxide， quartz， gibbsite， bauxite， feldspar， and mica， etc. Iron occurs in the form of hematite， limonite， iron-aluminum oxide and particulate silicon slag. There is a large amount of particulate silicon slag in red mud， but the mineral(phase)particle size is fine. The key to taking full advantage of the red mud is how to make use of iron， aluminum， titanium and sodium in the particulate silicon slag.

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Experimental Study of Low Dilution Drawing in Gently Inclined Thick Gypsum Deposit

JIA Hai-bo， REN Feng-yu， HE Rong-xing， DING Hang-xing

2019, 40 (11): 1617-1622. DOI: 10.12068/j.issn.1005-3026.2019.11.018

Abstract ( 566 )

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The physical experiment on optimization of the stope structure parameters in induced caving method was performed to reduce ore losing and degrading. The mineral particles and the effects of thickness of mineral grain， spacing of trenches and spacing of alleyways on the recovery rate were investigated. The results showed that when the thickness of mineral grain is more than 20m， induced caving method with double trench is applied， and the distance between trenches should be 18m. Induced caving method with tandem trenches is suitable for conditions when the thickness of mineral grain is less than 20m， and the distance between trenches should be 10m， and the distance between alleyways should be 8m.

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Ore Image Segmentation Method of Conveyor Belt Based on U-Net and Res_UNet Models

LIU Xiao-bo， ZHANG Yu-wei

2019, 40 (11): 1623-1629. DOI: 10.12068/j.issn.1005-3026.2019.11.019

Abstract ( 1603 )

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Aiming at the problem of inaccurate segmentation caused by the adhesion and edge blurring of the ore image in the conveyor belt， a method for ore image segmentation of conveyor belt based on U-Net and Res_UNet models is proposed. Firstly， the image to be segmented is processed by gray-scale， median filtering and adaptive histogram equalization， and then the pre-trained U-Net model is used to extract the image contour. Then， after binary image contour， the pre-trained Res_UNet model is used for contour optimization. Finally， OpenCV is used to obtain the segmentation result. Compared with watershed algorithm based on morphological reconstruction and NUR method for 10 test images， the proposed method for ore contour detection and optimization based on deep learning is more accurate， proving its effectiveness for image segmentation of conveyor belt ores.

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Study on Overlying Strata Movement Law in Backfill Mining of Gently Inclined Medium Thick Orebody

GUAN Shou-an， LI Shuang， JIN Chang-yu， LIU Dong

2019, 40 (11): 1630-1635. DOI: 10.12068/j.issn.1005-3026.2019.11.020

Abstract ( 634 )

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The laws of strata movement and surface subsidence during downward backfill mining of gently inclined medium thick orebody were studied. Typical exploration line profiles were numerically determined via FLAC3D. The river sand and cementing agent were adopted as the materials of the aggregate and barite powder to peform large-scale similar material model tests. The model test results were verified and analyzed via the numerical analysis software-3DEC. The results showed that the strata movement and surface subsidence can be effectively restrained by the method of backfill mining， and cause to the surface subsidence area to concentrate on the top of the orebody and move to the center of the orebody along with the downward mining process. It was also indicated that the mining of deep-buried orebody has less influence on the movement range of overlying strata than that of the shallow-buried orebody. The angle of strata movement and subsidence first decreased and then increased with the increase of the mining depth.The final settlement is mainly found to be cylindrical subsidence.

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Slope Structural Plane Measurement and Block Stability Analysis Based on UAV Photogrammetry

ZHU Cheng-jin， WANG Shu-hong， REN Yi-peng， SUN Zi-han

2019, 40 (11): 1636-1641. DOI: 10.12068/j.issn.1005-3026.2019.11.021

Abstract ( 780 )

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In order to improve the safety of the information acquisition process of the slope structural plane and the accuracy of the measurement results， the multi-angle photogrammetry of the unmanned aerial vehicle(UAV) is used to obtain the structural plane information， and the coordinates of the slope structural plane and the length of the exposure are obtained. A dynamic Delaunay triangulation is proposed to triangulate the model. The stability analysis of the exposed surface of the slope is carried out in combination with the block generation rule. The key block is identified on the slope and the GeoSMA-3D is used to verify the feasibility and accuracy. The results show that the maximum key block of point cloud cutting is 38.5748m³， and the maximum key block of GeoSMA-3D cutting is 38.5617m³. Meanwhile， the blocks are both in the center of the slope. For irregular fractured rock slopes， 3D point cloud cutting can better characterize the block position of 3D slopes， and it has certain advantages for guiding key block management.

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Matrix ORP Disturbance Characteristics and Its Affecting Factors in Subsurface Wastewater Infiltration System

LI Hai-bo， LI Ying-hua ， BAI Xue-yu， BAI Jia-ning

2019, 40 (11): 1641-1647. DOI: 10.12068/j.issn.1005-3026.2019.11.022

Abstract ( 550 )

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Previous studies supported that the matrix ORP (oxidation reduction potential) partition varied linearly in the vertical direction. Even if there is mutual penetration between micro-zones， it has not been experimentally confirmed. To reveal the disturbance feature of ORP and its affecting factors， a soil column simulation experiment was conducted to study how the hydraulic loads(HLs)and wet-dry period ratios(WDPRs)influenced the OPR. The results indicated that， under a moderate HL(0.1m³/(m²·d))， ORP micro-zones moved vertically along with the soil matrix inducted by WDPR. Nitrification zone expanded and denitrification zone zoomed out when DWPR was increased. Moreover， extreme small WDPR would cause nonlinear ORP partition， i.e.， mutual penetration between nitrification and denitrification zones. HL variety affected ORP micro-environment obviously， especially in the middle and lower layers of matrix while HL increased. Under 4h∶8h WDPR， linear ORP partition was the dominant trend along with HL variety.

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Structural Reliability Analysis Method Considering Load Sequence

KANG Yu-mei， LIU Zi-ao， WU Peng-fei

2019, 40 (11): 1648-1653. DOI: 10.12068/j.issn.1005-3026.2019.11.023

Abstract ( 592 )

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In view of the contradiction which load effects are assumed to be both independent and completely related in load-effect combination method recommended by JCSS ， and the ineffectiveness of time-interval analysis method for non-stationary load-effect process in engineering， structural reliability analysis method considering load sequence is performed. Firstly， the structural reliability analysis method under non-stationary load effect process is proposed. Secondly， the structural reliability calculation model under multi-period load considering load sequence is improved. Finally， the influence of structural damage on reliability is analyzed by cross-threshold theory， and the formula for calculating structural reliability considering non-stationary load process， loading sequence and structural damage is derived. The results showed that the method is more applicable and the calculation results are more realistic and reliable.

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Particle Flow Simulation of Failure Process in Single Fissured Sandstone Under True Tri-axial Compression

JIA Peng， ZHANG Yao， LIU Dong-qiao， ZHANG Ya-bing

2019, 40 (11): 1654-1659. DOI: 10.12068/j.issn.1005-3026.2019.11.024

Abstract ( 695 )

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A series of numerical simulations were conducted to analyze the crack propagation and failure mechanism of sandstone with an inner single fissure under true tri-axial compression by using the particle flow code. The effects of different intermediate principal stresses on the crack propagation and failure mechanical properties of fissured sandstone are discussed. Results show that under true tri-axial compression， the intermediate principal stress contributes to the increasing of the peak strength of the fissured sandstone， while a higher intermediate principal stress can accelerate the crack propagation thus form macroscopic fracture in the sandstone sample. When the direction of the intermediate principal stress is consistent with the strike of the inner-fissure， a shear fracture can form in the direction of the fissure strike. The failure of the fissured sandstone under true tri-axial compression is mainly the shear failure accompanied by tensile failure.

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Effect of Work-Family Balance on Innovation Performance of Female Knowledge Workers: A Cross-level Moderated Mediation Model

ZHANG Lan-xia， SONG Jia-yi， TAN Jun， WEI Cai-yun

2019, 40 (11): 1660-1666. DOI: 10.12068/j.issn.1005-3026.2019.11.025

Abstract ( 698 )

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According to the emotional events theory， situational forces theory and related literature， and based on the paired survey data of 101 supervisors and 378 employees， the cross-level analysis method was used to explore the passing mechanism between work-family balance and innovation performance of female knowledge workers and to analyze the moderating role of transformational leadership. The results showed that female knowledge workers′ work-family balance has a significant positive impact on innovation performance. Job well-being plays a mediating role between work-family balance and innovation performance of female knowledge workers. Transformational leadership moderates the mediating role of job well-being from work-family balance to innovation performance of female knowledge workers.

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Hotel Selection Based on Information of Hotel Features and Online Ratings

TAO Ling-ling， YOU Tian-hui， YUAN Yuan

2019, 40 (11): 1667-1672. DOI: 10.12068/j.issn.1005-3026.2019.11.026

Abstract ( 610 )

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In order to assist tourists to select hotels through tourism websites， a method for selecting desirable hotels is proposed based on features information and online ratings information of alternative hotels provided by tourism websites. Firstly， the directed and weighted graph of alternative hotels is constructed， in which hotel features are weighted objectively by the maximum deviation method based on hotel features information and then the node weights of directed weighted graph are determined by the simple weighting method. The directed edge and its weight are determined by comparing the online ratings information of node hotels. Then， the algorithm for calculating the sorting value of alternative hotels is given based on the principle of PageRank algorithm. Finally， in order to verify the effectiveness and feasibility of the proposed method， a case study on desirable hotel selection is proposed based on the information of hotel features and online ratings from the Booking.com website.

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