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Influence of surface roughness on the development of moss-dominated biocrusts on mountainous rock-cut slopes in West sichuan, china

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Journal of Mountain Science 2023年第8期20卷 2181-2196页

作者： ZHAO Xin-yue ZHAO Mao-qiang WANG Pan-pan DAI Yu-quan PU Wan-qiu HUANG Cheng-min Department of Environmental Science and Engineering Sichuan UniversityChengdu 610065China Jiuzhaigou Administration Bureau Jiuzhaigou 623402China sichuan Institute of Geological Engineering Investigation group co.LTD Chengdu 610072China

Since natural restoration co.bined with artificial auxiliary measures may achieve a relatively rapid restoration effect at a lower co.t, it has beco.e an essential measure for the eco.ogical restoration of rock slopes. Previous studies have focused heavily on the relationship between substrate nutrients and water co.ditions and the development of mosses on the rock surface, but quantitative characterization of substantial effect of rock surface texture(e.g., microrelief) on moss growth is absent. The undulating microrelief on the rock surface can increase the heterogeneity of the microhabitat, which may be an important factor affecting the development of mossdominated biocrusts. In this study, the roughness of rock surfaces, moss co.erage and biomass, weight and major nutrient co.tents of soils within the biocrusts were measured in the western mountainous area of sichuan Province, Southwest china to further examine the role of rock surface microrelief in the biocrusts. The results showed that three main factors affecting the development of the biocrusts were bryophyte emergence, soil accumulation, and lithology. The presence of moss accelerates soil formation on rock surfaces and lead to the accumulation of nutrients so that all parts of the moss-dominated biocrusts system can develop synergistically. It was found that a microrelief structure with a roughness between 1.5 and 2.5 co.ld gather soil and bryophyte propagules effectively, which may have a strong relationship with the angle of repose. When the roughness is 1.5, the co.responding undulation angle is very close to the theoretical minimum value of the undulation angle calculated acco.ding to the relationships between the undulation angle of the protrusion, slope and angle of repose.

关键词： Biocrusts Moss Natural restoration Repose angle Rock slope Roughness

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Approximate analytical solution for seepage field of drained tunnel in vertically stratified phreatic aquifer

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Journal of Mountain Science 2022年第5期19卷 1437-1455页

作者： MENG Wei HE Chuan WU Fang-yin YANG Wen-bo KOU Hao ZHOU Zi-han GUO De-ping MENG Hai-long Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China Xuzhen Railway co. LtdZhaotong 657900China sichuan Mianjiu Expressway co. LtdChengdu 621000China

To explore the water table and water inflow after tunnel excavation in a vertically stratified phreatic aquifer,approximate analytical solutions for the steady-state water table and water inflow of a drained tunnel in a vertically stratified phreatic aquifer were obtained based on the Dupuit assumptions and the integral *** co.paring the approximate analytical solutions with numerical solutions,it was found that the relative error of the approximate analytical solution for the water table elevation is less than 10%,and the relative error of the approximate analytical solution for the water inflow is approximately 25%.The sources of the above errors are as follows:(1)At the lateral boundary of water replenishment,the water surface should be tangent to the horizontal line,but the water surface for the approximate analytical solutions has a gradient.(2)At the vertical boundaries near the tunnel,the total head is variable,but the total head for the approximate analytical solutions is assumed to be co.stant.(3)The Dupuit assumptions are applied in the flow domain near the *** the relative errors of the approximate analytical solutions for the water table elevation and water inflow are evident,the lowered water table is reflected in the approximate analytical solutions.

关键词： Dupuit assumptions Water table Water inflow Tunnel engineering Equipotential line Integral method

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Evaluation of Voltage Quality and Energy Saving Benefits of Urban Rail Transit Power Supply Systems co.sidering the Access of Photovoltaics

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CSEE Journal of Power and Energy Systems 2023年第6期9卷 2309-2320页

作者： Ding Feng Hengkai Zhu Feng Wang Xiaojun Sun Sheng Lin Zhengyou He the School of Electrical Engineering Southwest Jiaotong UniversityChengdu 611756China. china Railway Design group co. Ltd.Tianjin 300000China

Along the route of urban rail transit(URT),the subway depots,parking lots,and elevated subway stations are equipped with sufficient photovoltaic(PV)generation *** access of PVs in the URT power supply system should not only make full use of nearby renewable energy,but also improve the eco.omic operation of the *** order to quantify the impact of PV access on the URT power supply system,this paper proposes a method to evaluate the voltage quality and energy saving benefits of the URT power supply system,co.sidering PV ***,by fully co.sidering the random fluctuations of PV output power,as well as the intermittency and impact of traction load,the URT power supply system with PV access is ***,such values as system voltage and power are calculated through the hybrid AC/DC load flow calculation *** with the results of the load flow calculation,the indicators describing voltage quality and power saving benefits of the system are proposed to quantify the influence of PV access on the ***,a case study co.cerning a certain section of a subway line is presented to verify the proposed *** shows that the proposed method can effectively quantify the voltage quality and power saving benefits of the system after PV access,providing valuable insights for design and maintenance personnel to co.prehend system state and operating characteristics.

关键词： Energy saving benefits photovoltaics urban rail transit voltage quality

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Wettability between titanium-co.taining steels and TiN ceramic substrate

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Journal of Iron and Steel Research International 2023年第4期30卷 677-686页

作者： Ya-cen Deng Hao Liu Min Zhang Xu-bin Zhang Qiang-qiang Wang Sheng-ping He co.lege of Materials Science and Engineering Chongqing Key Laboratory of Vanadium–Titanium Metallurgy and Advanced MaterialsChongqing UniversityChongqing 400044China Institute of Material Engineering and Technology Pangang Group Research Institute Co.Ltd.Panzhihua 617000SichuanChina

The wettability between TiN ceramic substrates and steels with various Ti co.tents was studied under an argon atmosphere at 1550℃ using a modified sessile drop *** electron probe microanalyzer and thermodynamic calculations were applied to investigate the interface between the steels and the TiN substrates as well as the surface of solidified steel *** measured apparent co.tact angles between the TiN substrates and steels were 96°,91°,and 146°,as the Ti co.tent in the steel samples was 0.01,0.31,and 0.68 wt.%,*** reaction products were found at the interface,and only physical interactions *** wettability between high titanium steels(0.68 wt.%Ti)and TiN ceramic substrates should be evaluated from various perspectives,as many TiN particles existing in steel made the apparent co.tact angle increased significantly,deviating from the true value of co.tact angle.

关键词： Wettability co.tact angle High-Ti steel TiN ceramic

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Pavement crack image acquisition methods and crack extraction algorithms:A review

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第6期6卷 535-556页

作者： Weixing Wang Mengfei Wang Hongxia Li Heng Zhao Kevin Wang Changtao He Jun Wang Sifan Zheng Jiabin Chen School of Information Engineering Chang an UniversityXi'an 710064China Royal Institute of Technology Stockholm 10044Sweden sichuan Jiuzhou Electric group co. LtdMianyang 621000China School of Electronics and Information Engineering Sichuan UniversityChengdu 610064China Intelligent Manufacturing Engineering co.lege Liming Vocational UniversityQuanzhou 362000China

The extraction of pavement cracks is always a hard task in image *** airport and road co.struction,cracking is the main factor for pavement damage,which can decrease the quality of pavement and affect transportation *** also exist in other artificial or natural objects,such as buildings,bridges,tunnels,*** all the object images,pavement crack images are the most co.plex,so the image processing and analysis for them is harder than other crack *** the early image acquisition based on photography technology to the current 3 D laser scanning technology,the pavement crack image acquisition technology is beco.ing more co.venient and efficient,but there are still challenges in the automatic processing and reco.nition of cracks in *** the early global thresholding to deep learning algorithms,the research for crack extraction has been developed for about 40 *** are many methods and algorithms that are satisfactory in pavement crack applications,but there is no standard until ***,in order to know the developing history and the advanced research,we have co.lected a number of literature in this research topic for summarizing the research artwork status,and giving a review of the pavement crack image acquisition methods and2 D crack extraction ***,for image acquisition methods and pavement crack image segmentation,more detailed co.parison and discussions are made.

关键词： Highway engineering Pavement crack Image acquisition Image processing Crack extraction

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Oxidation and internal nitridation behaviors of a Ni-based superalloy Rene 65 during high-temperature homogenization

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Journal of Iron and Steel Research International 2023年第8期30卷 1622-1632页

作者： Xian-guang Zhang Jia-jun Chen Yang Zhou Lang Shui Dong-ping Xiao Jian-hui Fu Wen-chao Yang Huan Liu Ying-jie Ren Peng Shi Jian Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing(USTB)Beijing 100083China School of Metallurgical and Eco.ogical Engineering University of Science and Technology Beijing(USTB)Beijing 100083China Chengdu Advanced Metal Materials Industrial Technology Institute co. Ltd.Chengdu 610300SichuanChina Iron and State Key Laboratory of Metal Material for Marine Equipment and Application Anshan 114009LiaoningChina Pangang group Research Institute co. Ltd.Panzhihua 617000SichuanChina

Homogenization heat treatment is a key process to remove the micro-segregation and re-dissolve the undesired phases for wrought *** oxidation behavior of the wrought superalloy during the high-temperature homogenization process,however,was rarely *** oxidation film evolution and growth kinetics of an as-cast superalloy Rene 65 during the homogenization were systematically *** oxide film co.sists of Cr_(2)O_(3) external oxidation layer and dendritic TiO_(2) and Al_(2)O_(3) internal oxidation *** the growth kinetics of the oxide film followed a parabolic *** nitridation occurs during the oxidation process,and TiN is apparently formed at the tip of internal oxidation *** originally formed TiN can be transformed into TiO_(2) or retained with the progress of ***,the TiN is newly formed in the deeper matrix at the new oxidation-layer *** analyses revealed that there is a co.petition between the oxidation and *** can occur when the partial pressure of nitrogen exceeds the threshold of nitridation and the critical partial pressure ratio of nitrogen and oxygen.

关键词： Nickel-based superalloy Homogenization Oxidation Kinetics Internal nitridation Thermodynamics

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VAECGAN:a generating framework for long-term prediction in multivariate time series

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Cybersecurity 2021年第1期4卷 337-348页

作者： Xiang Yin Yanni Han Zhen Xu Jie Liu Institute of Information Engineering Chinese Academy of SciencesSchool of Cyber SecurityUniversity of Chinese Academy of SciencesBeijingChina Institute of Information Engineering Chinese Academy of SciencesBeijingChina Network information department China Mobile Communications Group Co.LtdBeijingChina

Long-term prediction is still a difficult problem in data *** usually use various kinds of methods of Recurrent Neural Network to ***,with the increase of the prediction step,the accuracy of prediction decreases *** order to improve the accuracy of long-term prediction,we propose a framework Variational Auto-Enco.er co.ditional Generative Adversarial Network(VAECGAN).Our model is divided into three *** first part is the enco.er net,which can enco.e the exogenous sequence into latent space vectors and fully save the information carried by the exogenous *** seco.d part is the generator net which is responsible for generating prediction *** the third part,the discriminator net is used to classify and feedback,adjust data generation and improve prediction ***,extensive empirical studies tested with five real-world datasets(NASDAQ,SML,Energy,EEG,KDDCUP)demonstrate the effectiveness and robustness of our proposed approach.

关键词： Long-term prediction Multivariate time series Attention mechanism Generating framework

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Numerical simulation and analysis of the pile underpinning technology used in shield tunnel crossings on bridge pile foundations

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Underground Space 2021年第4期6卷 396-408页

作者： Zheng Li Ziquan Chen Lin Wang Zhikai Zeng Dongming Gu MOE Key Laboratory of Transportation Tunnel Engineering Southwest Jiaotong UniversityChengduSichuan 610031China Chongqing City co.struction Investment(group)co. LtdChongqing 400023China School of Civil Engineering Chongqing UniversityChongqing 400045China

Currently,the pile foundation underpinning technology is widely used when underground transportation infrastructure passes through existing buildings or structures in urban *** study aims to investigate stress transfer mechanisms in pile foundations during an underpinning process as well as the influence of shield tunnel co.struction on pile *** this end,the pile foundation underpinning technology used in china’s Shenzhen Metro Line 10 crossing through the bridge pile foundation group of the Guangzhou-Shenzhen highway was analyzed in *** refined numerical simulation of the pile foundation underpinning and shield tunnel co.struction processes were co.ducted using the fast Lagrangian analysis of co.tinua in 3 dimensions(FLAC3D)*** results demonstrate that after the pile foundation underpinned,the previous bridge load system of bridge panel→pile foundation→bearing soil would transform into a bridge panel→existing pile foundation→new underpinning pile→deep bearing soil stratum *** overlying load on the underpinned pile co.ld be effectively transferred to a new underpinning *** the process of underpinning and tunnel excavation,the settlement and deformation of the foundation can improve the tip resistance and shaft friction of piles,which in turn,can reduce the maximum principal stress in the pile foundation *** deformation of the bridge pile foundation is mainly caused by ground loss and excavation disturbance generated during shield tunneling as the settlement induced by pile foundation underpinning acco.nts for approximately 20%-30% of the total *** reduction effects of settlement deformation,lateral displacement,and principal stress are mainly manifested in underpinning piles,while the non-underpinning pile exhibits minimal ***,the deformation of the segment lining structure of the shield tunnel primarily occurs near the underpinning area of the pile foundation,and it is mainly settlemen

关键词： Bridge pile foundation Shield tunnel Pile underpinning technology Numerical simulation

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Unveiling the emerging role of curcumin to alleviate ochratoxin A-induced muscle toxicity in grass carp(Ctenopharyngodon idella):in vitro and in vivo studies

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1638-1656页

作者： Piao Zhao Lin Feng Weidan Jiang Pei Wu Yang Liu Hongmei Ren Xiaowan Jin Lu Zhang Haifeng Mi Xiaoqiu Zhou Animal Nutrition Institute Sichuan Agricultural UniversityChengdu 611130SichuanChina Fish Nutrition and Safety Production University Key Laboratory of sichuan Province Sichuan Agricultural UniversityChengdu 611130SichuanChina Key Laboratory of Animal Disease‑Resistance Nutrition Ministry of EducationMinistry of Agriculture and Rural AffairsKey Laboratory of Sichuan ProvinceChengdu 611130SichuanChina Tongwei co. Ltd.Healthy Aquaculture Key Laboratory of Sichuan ProvinceChengdu 610041SichuanChina

Background Ochratoxin A(OTA),a globally abundant and extremely hazardous pollutant,is a significant source of co.tamination in aquafeeds and is responsible for severe food *** developmental toxicity of OTA and the potential relieving strategy of natural products remain *** study screened the substance curcumin(Cur),which had the best effect in alleviating OTA inhibition of myoblast proliferation,from 96 natural products and investigated its effect and mechanism in reducing OTA myotoxicity in vivo and in *** A total of 720 healthy juvenile grass carp,with an initial average body weight of 11.06±0.05 g,were randomly assigned into 4 groups:the co.trol group(without OTA and Cur),1.2 mg/kg OTA group,400 mg/kg Cur group,and 1.2 mg/kg OTA+400 mg/kg Cur *** treatment co.sisted of 3 replicates(180 fish)for 60 *** Firstly,we cultured,purified,and identified myoblasts using the tissue block culture *** preliminary screening and re-screening of 96 substances,we examined cell proliferation-related indicators such as cell viability and ultimately found that Cur had the best ***,Cur co.ld alleviate OTA-inhibited myoblast differentiation and myofibrillar development-related proteins(Myo G and MYHC)in vivo and in vitro and improve the growth performance of grass ***,Cur co.ld also promote the expression of OTA-inhibited protein synthesis-related proteins(S6K1 and TOR),which was related to the activation of the AKT/TOR signaling ***,Cur co.ld downregulate the expression of OTA-enhanced protein degradation-related genes(murf1,foxo3a,and ub),which was related to the inhibition of the Fox O3a signaling *** In summary,our data demonstrated the effectiveness of Cur in alleviating OTA myotoxicity in vivo and in *** study co.firms the rapidity,feasibility,and effectiveness of establishing a natural product screening method targeting myoblasts to alleviate fungal toxin toxicity.

关键词： Curcumin Grass carp Myotoxic Ochratoxin A Protein deposition

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A Survey of Embedding Algorithm for Virtual Network Embedding

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china co.munications 2019年第12期16卷 1-33页

作者： Haotong Cao Shengchen Wu Yue Hu Yun Liu Longxiang Yang Jiangsu Key Laboratory of Wireless co.munications Nanjing University of Posts and TelecommunicationsNanjing 210003China Department of Key Acco.nts China Mobile Group Jiangsu Co.Ltd.Nanjing 210029China School of Biomedical Engineering and Information Nanjing Medical UniversityNanjing 211166China

Network virtualization(NV) is pushed forward by its proponents as a crucial attribute of next generation network, aiming at overco.ing the gradual ossification of current networks, particularly to the worldwide Internet. Through virtualization, multiple customized virtual networks(VNs), requested by users, are allowed to co.xist on the underlying substrate networks(SNs). In addition, the virtualization scheme co.tributes to sharing underlying physical resources simultaneously and seamlessly. However, multiple technical issues still stand in the way of NV successful implementation. One key technical issue is virtual network embedding(VNE), known as the resource allocation problem for NV. This paper co.ducts a survey of embedding algorithms for VNE problem. At first, the NV business model for VNE problem is presented. Then, the latest VNE problem description is presented. Main performance metrics for evaluating embedding algorithms are also involved. Afterwards, existing VNE algorithms are detailed, acco.ding to the novel proposed category approach. Next, key future research aspects of embedding algorithms are listed out. Finally, the paper is briefly co.cluded.

关键词： network virtualization virtual network embedding embedding algorithms key future research aspects

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