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Estimation and testing of linkages between forest structure and rainfall interception characteristics of a Robinia pseudoacacia plantation on China’s Loess Plateau

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Journal of Forestry Research 2022年第2期33卷 529-542页

作者： Changkun Ma Yi Luo Mingan Shao Xiaoxu Jia State Key Laboratory of Eco-Hydraulics in Northwest Arid Region Xian University of TechnologyXianChina Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China

Understanding the interaction between canopy structure and the parameters of interception loss is essential in predicting the variations in partitioning rainfall and water resources as affected by changes in canopy structure and in implementing water-based management in semiarid forest *** this study,seasonal variations in rainfall interception loss and canopy storage capacity as driven by canopy structure were predicted and the linkages were tested using seasonal filed *** study was conducted in nine 50 m×50 m Robinia pseudoacacia plots in the semiarid region of China’s Loess *** rain-fall,throughfall and stemflow were measured in seasons with and without leaves in 2015 and *** show that measured average interception loss for the nine plots were 17.9% and 9.4% of gross rainfall during periods with leaves (the growing season) and without leaves, respectively. Average canopy storage capacity estimated using an indirect method was 1.3 mm in the growing season and 0.2 mm in the leafless season. Correlations of relative interception loss and canopy storage capacity to canopy variables were highest for leaf/wood area index (LAI/WAI) and canopy cover, fol-lowed by bark area, basal area, tree height and stand density. Combined canopy cover, leaf/wood area index and bark area multiple regression models of interception loss and canopy storage capacity were established for the growing season and in the leafless season in 2015. It explained 97% and 96% of the variations in relative interception loss during seasons with and without leaves, respectively. It also explained 98% and 99% of the variations in canopy storage capacity during seasons with and without leaves, respectively. The empiri-cal regression models were validated using field data col-lected in 2016. The models satisfactorily predicted relative interception loss and canopy storage capacity during seasons with and without leaves. This study provides greater under-standing a

关键词： Rainfall interception loss Canopy storage Canopy structure regression models China’s Loess Plateau

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Quick identification of guidance law for an incoming missile using multiple-model mechanism

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Chinese Journal of Aeronautics 2022年第9期35卷 282-292页

作者： Yinhan WANG Shipeng FAN Jiang WANG Guang WU School of Aerospace Engineers Beijing Institute of TechnologyBeijing 10081China Beijing Aerospace Automatic Institute Beijing 100854China

A guidance law parameter identification model based on Gated Recurrent Unit(GRU)neural network is established. The scenario of the model is that an incoming missile(called missile)attacks a target aircraft(called aircraft) using Proportional Navigation(PN) guidance law. The parameter identification is viewed as a regression problem in this paper rather than a classification problem, which means the assumption that the parameter is in a finite set of possible results is discarded. To increase the training speed of the neural network and obtain the nonlinear mapping relationship between kinematic information and the guidance law parameter of the incoming missile, an output processing method called Multiple-Model Mechanism(MMM) is proposed. Compared with a conventional GRU neural network, the model established in this paper can deal with data of any length through an encoding layer in front of the input layer. The effectiveness of the proposed Multiple-Model Mechanism and the performance of the guidance law parameter identification model are demonstrated using numerical simulation.

关键词： Gated recurrent unit Multiple-model mechanism Neural networks Parameter identification regression models

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A mesh optimization method using machine learning technique and variational mesh adaptation

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Chinese Journal of Aeronautics 2022年第3期35卷 27-41页

作者： Tingfan WU Xuejun LIU Wei AN Zenghui HUANG Hongqiang LYU MIITKey Laboratory of Pattern Analysis and Machine Intelligence College of Computer Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 211106China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing 210023China College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Computational mesh is an important ingredient that affects the accuracy and efficiency of CFD numerical *** light of the introduced large amount of computational costs for many adaptive mesh methods,moving mesh methods keep the number of nodes and topology of a mesh unchanged and do not increase CFD computational *** the state-of-the-art moving mesh method,the variational mesh adaptation approach has been introduced to CFD ***,quickly estimating the flow field on the updated meshes during the iterative algorithm is challenging.A mesh optimization method,which embeds a machine learning regression model into the variational mesh adaptation,is *** regression model captures the mapping between the initial mesh nodes and the flow field,so that the variational method could move mesh nodes iteratively by solving the mesh functional which is built from the estimated flow field on the updated mesh via the regression *** the optimization,the density of the nodes in the high gradient area increases while the density in the low gradient area *** examples are first used to verify the feasibility and effectiveness of the proposed *** then we use the steady subsonic and transonic flows over cylinder and NACA0012 airfoil on unstructured triangular meshes to test our *** show that the proposed method significantly improves the accuracy of the local flow features on the adaptive *** work indicates that the proposed mesh optimization approach is promising for improving the accuracy and efficiency of CFD computation.

关键词： CFD Flow field Machine learning Moving mesh method regression models Variational mesh adaptation

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Influence of urban morphological factors on building energy consumption combined with photovoltaic potential: A case study of residential blocks in central China

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建筑模拟(英文) 2023年第9期16卷 1777-1792页

作者： Shen Xu Mengcheng Sang Mengju Xie Feng Xiong Thushini Mendis Xingwei Xiang School of Architecture and Urban Planning Huazhong University of Science and TechnologyWuhanChina Hubei New Urbanization Engineering and Technology Research Center WuhanChina Department of Architecture and Built Environment University of Nottingham Ningbo ChinaNingboChina

Studies on urban energy have been growing in interest,and past research has mostly been focused on studies of urban solar potential or urban building energy consumption ***,holistic research on the combination of urban building energy consumption and solar potential at the urban block-scale is required in order to minimize energy use and maximize solar power generation *** aim of this study is to comprehensively evaluate the impact of urban morphological factors on photovoltaic(PV)potential and building energy ***,58 residential blocks were classified into 6 categories by k-means ***,3 energy performance factors,which include the energy use intensity(EUI),the energy use intensity combined with PV potential(EUI-PV),and photovoltaic substitution rate(PSR)were calculated for these *** study found that the EUI of the Small Length&High Height blocks was the lowest at around 30 kWh/(m^(2)·y),while the EUI-PV of the Small Length&Low Height blocks was the lowest at around 4.45 kWh/(m^(2)·y),and their PSR was the highest at 87%.regression modelling was carried out,and the study concluded that the EUI of residential blocks was mainly affected by shape factor,building density and floor area ratio,while EUI-PV and PSR were mainly affected by height and sky view *** this study,the results and developed methodology are helpful to provide recommendations and strategies for sustainable planning of residential blocks in central China.

关键词： urban morphological factors residential blocks building energy consumption photovoltaic potential regression models

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An innovative model for predicting the displacement and rotation of column-tree moment connection under fire

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Frontiers of Structural and Civil Engineering 2021年第1期15卷 194-212页

作者： Mohammad Ali NAGHSH Aydin SHISHEGARAN Behnam KARAMI Timon RABCZUK Arshia SHISHEGARAN Hamed TAGHAVIZADEH Mehdi MORADI Department of Civil Engineering Isfahan University of TechnologyIsfahan 84156-83111Iran School of Civil Engineering School of Civil EngineeringIran University of Science and TechnologyTehran 13114-16846Iran Department of Civil Engineering International Institute of Earthquake Engineering and SeismologyTehran 19539-14453Iran Division of Computational Mechanics Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Civil Engineering Ton Duc Thang UniversityHo Chi Minh CityVietnam Department of Civil Engineering Islamic Azad UniversityTehran 16511-53311Iran Department of Civil Engineering Isfahan UniversityIsfahan 81746-73441Iran

In this study,we carried out nonlinear finite element simulations to predict the performance of a columntree moment connection(CTMC)under fire and static *** also conducted a detailed parameter study based on five input variables,including the applied temperature,number of flange bolts,number of web bolts,length of the beam,and applied static *** first variable is changed among seven levels,whereas the other variables are changed among three *** the Taguchi method for variables 2-5 and their levels,9 samples were designed for the parameter study,where each sample was exposed to 7 different temperatures yielding 63 *** related variables for each output are imported for the training and testing of different surrogate *** surrogate models include a multiple linear regression(MLR),multiple Ln equation regression(MLnER),an adaptive network-based fuzzy inference system(ANFIS),and gene expression programming(GEP).44 samples were used for training randomly while the remaining samples were employed for *** show that GEP outperforms MLR,MLnER,and *** results indicate that the rotation and deflection of the CTMC depend on the *** addition,the fire resistance increases with a decrease in the beam length;thus,a shorter beam can increase the fire resistance of the *** numbers of flanges and web bolts slightly affect the rotation and displacement of the CTMCs at temperatures of above 400℃.

关键词： column-tree moment connection Finite element model parametric study fire regression models gene expression programming

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Unified methodology for site-characterization and sampling of highway runoff

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Frontiers of Environmental Science & Engineering 2010年第1期4卷 47-58页

作者： Jy S.WU Craig J.ALLAN Department of Civil and Environmental Engineering University of North Carolina at CharlotteCharlotteNC 28223USA 2 Department of Geography and Earth SciencesUniversity of North Carolina at CharlotteCharlotteNC 28223USA

Hydrology,roadway traffic conditions,and atmospheric deposition are three essential data categories for the planning and implementation of highway-runoff monitoring and characterization *** variables pertaining to each data category could be site specific but have been shown to correlate with runoff pollutant *** data categories were combined to derive statistical relationships for characterization and prioritization of the respective pollutant loads at highway runoff *** runoff data of total suspended solids(TSS),total dissolved solid(TDS),chemical oxygen demand(COD),total Kjeldahl nitrogen(TKN)and total phosphorus(TP)collected from three highway sites in Charlotte,North Carolina,USA,were used to illustrate the development of site-specific highway-runoff pollutant loading *** unified methodology provides a basis for initial assessment of the pollutant-constituent loads from highway runoff using hydrologic component *** reliability is achievable when additional traffic and/or atmospheric component variables are incorporated into the basic hydrologic regression *** addition,operational guidance is suggested for implementing highway-runoff monitoring programs that are subject to sampling and resources constraints.

关键词： highway runoff pollutant loads regression models non-point source pollution storm water permit

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Risk-adjustment in hepatobiliarypancreatic surgery

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World Journal of Gastroenterology 2005年第16期11卷 2450-2455页

作者： Hemant M Kocher Paris P Tekkis Palepu Gopal Ameet G Patel Simon Cottam Irving S Benjamin Academic Department of Surgery King's College Hospital Denmark HillLondon SE5 9RYUK Department of Anaesthesia King's College Hospital Denmark HillLondon SE5 9RYUK

AIM: The present study evaluates the performance of the POSSUM, the American Society of Anesthetists (ASA), APACHE and Childs classification in predicting mortality and morbidity in hepatopancreaticobiliary (HPB) surgery. We describe especially the limitations and advantages of risk in stratifying the patients. METHODS: We investigated 177 randomly chosen patients undergoing elective complex HPB surgery in a single institution with a total of 71 pre-operative and intra-operative risk factors. Primary endpoint was in-hospital mortality and morbidity. Ordered logistic regression analysis was used to identify individual predictors of operative morbidity and mortality. RESULTS: The operative mortality in the series was 3.95%. This compared well with the p-POSSUM and APACHE predicted mortality of 4.31% and 4.29% respectively. Postoperative complications amounted to 45% with 24 (13.6%) patients having a major adverse event. On multrvariate analysis the pre-operative POSSUM physiological score (OR = 1.18, P = 0.009) was superior in predicting complications compared to the ASA (P= 0.108), APACHE (P= 0.117) or Childs classification (P= 0.136). In addition, serum sodium, creatinine, international normalized ratio (INR), pulse rate, and intra-operative blood loss were independent risk factors. A combination of the POSSUM variables and INR offered the optimal combination of risk factors for risk prognostication in HPB surgery. CONCLUSION: Morbidity for elective HPB surgery can be accurately predicted and applied in everyday surgical practice as an adjunct in the process of informed consent and for effective allocation of resources for intensive and high-dependency care facilities.

关键词： Hepatobiliarypancreatic surgery Risk adjustment Operative mortality Operative morbidity regression models

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Rainfall erosivity and erosivity density through rainfall synthetic series for Sao Paulo State,Brazil:Assessment,regionalization and modeling

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International Soil and Water Conservation Research 2022年第3期10卷 355-370页

作者： David Bruno de Sousa Teixeira Roberto Avelino Cecílio Joao Paulo Bestete de Oliveira Laura Thebit de Almeida Gabrielle Ferreira Pires Department of Agricultural Engineering Federal University of ViçosaViçosaMG36570-900Brazil Department of Forest and Wood Sciences Federal University of Espírito SantoJer^onimo MonteiroES29550-000Brazil Federal Institute of Espírito Santo Campus AlegreAlegreES29520-000Brazil

Rainfall is the main cause of erosion of Brazilian soils,which makes assessing the rainfall erosivity factor(RE)and the erosivity density(ED)fundamental for soil and water ***,the objectives of this study were:i)to estimate the RE and ED for Sao Paulo State,Brazil,using synthetic series of pluviographic data;ii)to define homogeneous regions regarding rainfall erosivity;and iii)to generate regression models for rainfall erosivity estimates in each of the homogeneous *** series of pluviographic data were initially obtained on a sub-daily scale from the daily rainfall records of 696 rainfall *** RE values were then estimated from the synthetic rainfall data,and ED was calculated from the relationship between erosivity and rainfall *** and annual maps for RE and ED were *** clustering analysis was used to define homogeneous regions in terms of rainfall erosivity,and regionalized regression models for estimating RE were *** results demonstrate high spatial variability of RE in Sao Paulo,where the highest annual values were observed in the coastal *** to March concentrate approximately 60%of the intra-annual *** highest values of annual ED were observed in regions with intense agricultural *** definition of five homogeneous regions concerning the rainfall erosive potential evidenced distinct seasonal patterns of the spatial distribution of ***,the high predictive accuracy of the regionalized models obtained characterizes them as essential tools for reliable estimates of rainfall erosivity,and contribute to better soil conservation planning.

关键词： Soil erosion Stochastic weather generator Homogeneous regions Modified Fournier index regression models

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Spectral parameter-based models for leaf potassium concentration estimation in Ping'ou hybrid hazelnut

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Journal of Arid Land 2020年第6期12卷 1083-1092页

作者： ZHAO Shanchao PAN Cunde College of Forestry and Horticulture Xinjiang Agricultural UniversityUrumqi 830052China

Ping′ou hybrid hazelnut is produced by cross cultivation and is widely cultivated in northern China with good development *** on a field experiment of fertilizer efficiency,the leaf spectral reflectance and leaf potassium(K)concentration were measured with different quantities of K fertilizer applied at four fruit growth stages(fruit setting stage,fruit rapid growth stage,fruit fat-change stage,and fruit near-maturity stage)of Ping′ou hybrid hazelnut in *** parameters that were significantly correlated with leaf K concentration were selected using Pearson correlation analysis,and spectral parameter estimation models of leaf K concentration were established by employing six different modelling methods(exponential function,power function,logarithmic function,linear function,quadratic function,and cubic function).The results indicated that at the fruit setting period,leaf K concentration was significantly correlated with Dy(spectra slope of yellow edge),Rg(reflectance of the green peak position),λo(red valley position),SDb(blue edge area),SDr/SDb(where SDr represents red edge area),and(SDr–SDb)/(SDr+SDb)(Pregression estimation model of leaf K concentration with highest fitting degree(R2)values at the four fruit growth stages was *** findings in this study demonstrated that it is feasible to estimate leaf K concentration of Ping′ou hybrid hazelnut at the various phenological stages of fruit development by establishing

关键词： leaf K concentration spectrum cubic function regression models fruit growth stages Ping'ou hybrid hazelnut

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Morphometry of leaf and shoot variables to assess aboveground biomass structure and carbon sequestration by different varieties of white mulberry(Morus alba L.)

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Journal of Forestry Research 2021年第6期32卷 2291-2300页

作者： Ghulam Ali Bajwa Muhammad Umair Yasir Nawab Zahid Rizwan Pakistan Forest Institute Peshawar 25130Pakistan National Textile University Faisalabad 37610Pakistan

Mulberry is economically important and can also play a pivotal role in mitigating greenhouse *** and shoot traits were measured for Morus alba ***,*** ***,*** ***,and *** ***-1 to assess aboveground biomass(AGB)and carbon ***-specific and multivariety allometric AGB models were developed using the equivalent diameter at breast height(EDBH)and plant height(H).The completeharvest method was used to measure leaf and shoot traits and biomass,and the ash method was used to measure organic carbon *** results showed significant(pmodels b(EDBH)and b(EDBH)2 showed good fit and reasonable accuracy with a coefficient of determination(R^(2))=0.98-0.99,standard error of estimates(SEE)=0.1125-0.3130 and root mean square error(RMSE)=*** multivariety models bln(EDBH)and(EDBH)0.756 showed good-fitness and accuracy with R^(2)=0.85-0.86,SEE=1.6231-1.6445 and RMSE=*** the basis of these findings,variety Latifolia has good potential for biomass production,and allometric equations based on EDBH can be used to estimate AGB with a reasonable accuracy.

关键词： Allometry Biomass estimation CO_(2)mitigation Moraceae Mulberry regression models

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