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THE ROLE FORE AIR FLOW IN SOIL SLOPE STABILITY ANALYSIS

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Journal of Hydrodynamics 2009年第5期21卷 640-646页

作者： zhang xiao-yue zhu Yue-ming FANG Chun-hui College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

In order to investigate the effect of the pore air flow in the soil slope stability analysis, a water-air two-phase flow model, based on the multi-phase flow theory, is proposed and with the model, the water-phase and air-phase seepages of the soil slope in the stable seepage and rainfall situations are simulated. The soil slope safety coefficients are obtained according to the simulated pore air pressure and pore water pressure. The calculation results show that in the stable seepage situation, the influence of the pore air pressure on the soil slope stability can be neglected, while in the rainfall situation, the pore air pressure generated in the unsaturated zone will reduce the safety coefficient, and the larger the distance between the slip surface and the underground water level is, the greater the influence of the pore air pressure on the soil slope stability will be.

关键词： unsaturated soil water-air two-phase flow rainfall slope stability

IR-YOLO: Real-Time Infrared Vehicle and Pedestrian Detection

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Computers, Materials & Continua 2024年第2期78卷 2667-2687页

作者： xiao Luo Hao zhu Zhenli zhang Department of Electrical Engineering and Automation Jiangxi University of Science and TechnologyGanzhou341000China Jiangxi Provincial Key Laboratory of Maglev Technology Ganzhou341000China Graduate School of Information Production and SystemsWaseda UniversityKitakyushu-shiFukuoka808-0135Japan

Road traffic safety can decrease when drivers drive in a low-visibility *** application of visual perception technology to detect vehicles and pedestrians in infrared images proves to be an effective means of reducing the risk of *** tackle the challenges posed by the low recognition accuracy and the substan-tial computational burden associated with current infrared pedestrian-vehicle detection methods,an infrared pedestrian-vehicle detection method A proposal is presented,based on an enhanced version of You Only Look Once version 5(YOLOv5).First,A head specifically designed for detecting small targets has been integrated into the model to make full use of shallow feature information to enhance the accuracy in detecting small ***,the Focal Generalized Intersection over Union(GIoU)is employed as an alternative to the original loss function to address issues related to target overlap and category ***,the distribution shift convolution optimization feature extraction operator is used to alleviate the computational burden of the model without significantly compromising detection *** test results of the improved algorithm show that its average accuracy(mAP)reaches 90.1%.Specifically,the Giga Floating Point Operations Per second(GFLOPs)of the improved algorithm is only *** contrast,the improved algorithms outperformed the other algorithms on similar GFLOPs,such as YOLOv6n(11.9),YOLOv8n(8.7),YOLOv7t(13.2)and YOLOv5s(16.0).The mAPs that are 4.4%,3%,3.5%,and 1.7%greater than those of these algorithms show that the improved algorithm achieves higher accuracy in target detection tasks under similar computational resource *** the other hand,compared with other algorithms such as YOLOv8l(91.1%),YOLOv6l(89.5%),YOLOv7(90.8%),and YOLOv3(90.1%),the improved algorithm needs only 5.5%,2.3%,8.6%,and 2.3%,respectively,of the *** improved algorithm has shown significant advancements in balancing accuracy and computati

关键词： Traffic safety infrared image pedestrians and vehicles focal GIoU distributed shift convolution

First Total Synthesis of 12-Hydroxy-13-methylpodocarpa-9, 11, 13-trien-3-one

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Chinese Chemical Letters 2006年第2期17卷 163-164页

作者： Cheng Lu zhang xiao Lei zhu Ying Ge MA Li Wei ZOU Department of Chemistry Liaoning Normal University Dalian 116029

A ftrst facile total synthesis of 12-hydroxy- 13-methylpodocarpa-9, 11, 13-trien-3-one 9 was accomplished via a strategy of AC→ABC. In the synthetic process, compound 5 was synthesized through Reimer-Teimann reaction, followed by methylation, reduction, dehydration, addition to ethylene epoxide and chlorination. The target compound 9 was finally obtained through the condensation of Grignard reagent of compound 5 with 6, followed by intramolecular cyclization, reduction and demethylation.

关键词： Total synthesis 12-hydroxy-13-methylpodocarpa-9 11 13-trien-one diterpene.

Research on blade tip clearance cavitation and turbulent kinetic energy characteristics of axial flow pump based on the partially-averaged Navier-Stokes model

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Journal of Hydrodynamics 2024年第1期36卷 184-201页

作者： xiao-qi Jia Shuai-kang zhang Zu-chao zhu Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou310018China

To reveal the cavitation forms of tip leakage vortex(TLV)of the axial flow pump and the flow mechanism of the flow field,this research adopts the partially-averaged Navier-Stokes(PANS)model to simulate the cavitation values of an axial flow pump,followed by experimental *** experimental result shows that compared with the shear stress transport(SST)k-ωmodel,the PANS model significantly reduces the eddy viscosity of the flow field to make the vortex structure clearer and allow the turbulence scale to be more robustly *** cavitation area within the axial flow pump mainly comprises of TLV cavitation,clearance cavitation and tip leakage flows combined effect of triangular cloud cavitation *** formation and development of cavitation are accompanied by the formation and evolution of vortex,and variations in vortex structure also generate and promote the development of *** addition,an in-depth analysis of the relationship between the turbulent kinetic energy(TKE)transport equation and cavitation patterns was also conducted,finding that the regions with relatively high TKE are mainly distributed around gas/liquid boundaries with serious cavitation and evident gas-liquid *** phenomenon is mainly attributed to the combined effect of the pressure action term,stress diffusion term and TKE production term.

关键词： Cavitation axial flow pump tip leakage vortex(TLV) partially-averaged Navier-Stokes(PANS)model turbulent kinetic energy(TKE)

Developing microwave-induced thermoacoustic tomography:System,application,and reconstruction

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Journal of Electronic Science and Technology 2023年第4期21卷 1-19页

作者： Shuang-Li Liu Wan-Ting Peng xiao-zhang zhu Jian Song Xin Shang Hua zhang Zhi-Qin Zhao School of Information Engineering Southwest University of Science and TechnologyMianyang621010China School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China Yunnan Key Laboratory of Computer Technologies Application Kunming University of Science and TechnologyKunming650500China

A microwave-induced thermoacoustic imaging(MITAT)system is a non-destructive physical medical imaging method that combines the advantages of the high contrast of microwave imaging and the high resolution of ultrasound *** uses the microwave as the excitation source and ultrasound as the information *** different kinds of biological tissue absorb electromagnetic energy,it results in localized temperature *** thermal expansion will induce ultrasonic signals(i.e.,thermoacoustic signals),known as the thermoacoustic *** microwave absorption image of the sample can be reconstructed by algorithm *** MITAT contrast depends on different dielectric parameters of different kinds of *** introduce the developed system and its *** addition,the challenges and prospects of MITAT for further development are discussed.

关键词： Application Microwave-induced thermoacoustic tomography(MITAT) Reconstruction System

Controlling secondary flow in high-lift low-pressure turbine using boundary-layer slot suction

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Chinese Journal of Aeronautics 2024年第3期37卷 21-33页

作者： xiao QU Liunan LI Yingjie zhang Xingen LU Junqiang zhu Yanfeng zhang School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing 100190China

The design of high-lift Low-Pressure Turbines(LPTs)causes the separation of the boundary layer on the suction side of the blade and leads to a strong secondary *** present study aims to minimize secondary losses through endwall slot suction and incoming wakes in a front-loaded high-lift LPT cascade with Zweifel of 1.58 under low Reynolds number of *** slotted schemes for the boundary layer of the endwall were designed(Plan A and Plan B),and the effects of suction mass flow on secondary flow were *** underlying physics of the endwall boundary layer of the suction and secondary flow under unsteady wakes was *** results show that slot suction at the endwall boundary layer can significantly suppress the secondary flow by removing low-momentum *** A and B significantly reduced the secondary kinetic energy by 44.2%and 36.9%,respectively,compared with the baseline cascade at the suction mass flow ratios of 1%.With an increase in the mass flow ratio of suction,the secondary flow was gradually reduced in both Plans A and *** is more beneficial to control the secondary flow to destroy the intersection of the pressure side and suction side of the horseshoe vortex before it develops into a passage *** unsteady wakes,the combined effects of incoming wakes and endwall boundary layer suction can further suppress the secondary flow at the suction mass flow ratios of 2%for Plan A,because the positive and negative vorticity inside upstream wakes accelerated the mixing of the main flow and secondary flow and thus increased the energy of secondary vortices.

关键词： Low-pressure turbine Secondary flow Flow control Boundary-layer suction Incoming wake

The Distribution of Surnames in Xiantao City through Isonymy

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Journal of Geodesy and Geoinformation Science 2024年第2期7卷 52-65页

作者： zhang Jingjing zhu Yan xiao Hong College of Chinese Language and Literature Wuhan UniversityWuhan 430072China College of Literature and Communication China Three Gorges UniversityYichang 443002China School of Foreign Languages China University of GeosciencesWuhan 430072China

The population migration in Hubei Province was frequent in history,accompanied by the migration of surnames,so it is important to study their population *** take Xiantao City as an example to explore the isonymic structure of small and medium-sized cities in *** surname distributions of 223327 residents registered in 2013 were analyzed in 5 towns and 105 villages of *** number of different surnames found was *** for surnames,theα-value reflects the influence of ethnic composition on the abundance of *** correlation between the isonymic distance and the geographic distance between villages was calculated and indicated that Euclidean distance was weakly correlated with the geographic distance(r=0.177±0.012),and the isonymic distance increased with the geographical ***,the dendrogram and PCA built from the matrix of Euclidean distances between villages identified a main surname differentiation between the urban and rural areas.

关键词： Xiantao City surname distribution isonymy isolation by distance urban and rural areas

Atmospheric transmission algorithm for pulsed X-rays from high-altitude nuclear detonations based on scattering correction

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Nuclear Science and Techniques 2024年第3期35卷 40-52页

作者： Ding-Han zhu Xiong zhang xiao-Qiang Li Peng Li Yan-Bin Wang Shuang zhang State Key Laboratory of NBC Protection for Civilian Beijing 102205China

In high-altitude nuclear detonations,the proportion of pulsed X-ray energy can exceed 70%,making it a specific monitoring signal for such *** pulsed X-rays can be captured using a satellite-borne X-ray detector following atmospheric *** quantitatively analyze the effects of different satellite detection altitudes,burst heights,and transmission angles on the physical processes of X-ray transport and energy fluence,we developed an atmospheric transmission algorithm for pulsed X-rays from high-altitude nuclear detonations based on scattering *** proposed method is an improvement over the traditional analytical method that only computes direct-transmission *** traditional analytical method exhibits a maximum relative error of 67.79% compared with the Monte Carlo *** improved method reduces this error to within 10% under the same conditions,even reaching 1% in certain ***,its computation time is 48,000 times faster than that of the Monte Carlo *** results have important theoretical significance and engineering application value for designing satellite-borne nuclear detonation pulsed X-ray detectors,inverting nuclear detonation source terms,and assessing ionospheric effects.

关键词： High-altitude nuclear detonation Atmospheric transmission Pulsed X-rays Scattering correction Analytical method Monte Carlo method

Association of complement components with risk of colorectal cancer:A systematic review and meta-analysis

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2168-2180页

作者： xiao-Lin zhu Lu zhang Su-Xia Qi Department of Gastroenterology Qingdao Municipal HospitalQingdao 266071Shandong ProvinceChina Department of Medical Administration Qingdao Municipal HospitalQingdao 266071Shandong ProvinceChina

BACKGROUND Complement components could contribute to the tumor microenvironment and the systemic immune ***,their role in colorectal cancer(CRC)remains a contentious *** To elucidate the relationship between complement components and CRC risk and clinical *** Searches were conducted in PubMed,the Cochrane Library,and the China National Knowledge Infrastructure database until June 1,*** included cohort studies encompassing participants aged≥18 years,investigating the association between complement components and *** studies were of moderate quality or above,as determined by the Agency for Healthcare Research and *** meta-analysis employed fixed-effects or random-effects models based on the I^(2)test,utilizing risk ratio(RR)and their corresponding 95%confidence interval(CI)for *** and subgroup analyses were performed to validate the robustness of the collective estimates and identify the source of *** Data from 15 studies,comprising 1631 participants that met the inclusion criteria,were included in the *** findings indicated that protein levels of cluster of differentiation 46(CD46)(RR=3.66,95%CI:1.75-7.64,P<0.001),CD59(RR=2.86,95%CI:1.36-6.01,P=0.005),and component 1(C1)(RR=5.88,95%CI:1.75-19.73,P=0.004)and serum levels of C3(standardized mean difference=1.82,95%CI:0.06-3.58,P=0.040)were significantly elevated in patients with CRC compared to healthy *** expression of CD55 or CD59 was associated with a higher incidence of lymph node metastasis,whereas strong CD46 expression correlated with a higher incidence of tumor differentiation compared to low CD46 expression(P<0.05 for all).Although specific pooled results demonstrated notable heterogeneity,subgroup analyses pointed to regional differences as the primary source of inconsistency among the *** Our analysis underscores that increased levels of specific complement components are

关键词： Complement components Colorectal cancer Lymph node metastasis Systematic review Meta-analysis