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A modeling approach to determine substitutive tree species for sweet chestnut in stands affected by ink disease
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作者 Malve Heinz Simone Prospero 《Journal of Forestry Research》 2025年第3期237-253,共17页
Biological invasions,driven mainly by human activities,pose significant threats to global ecosystems and economies,with fungi and fungal-like oomycetes playing a pivotal role.Ink disease,caused by Phytophthora cinnamo... Biological invasions,driven mainly by human activities,pose significant threats to global ecosystems and economies,with fungi and fungal-like oomycetes playing a pivotal role.Ink disease,caused by Phytophthora cinnamomi and P.×cambivora,is a growing concern for sweet chestnut stands(Castanea sativa)in Europe.Since both pathogens are thermophilic organisms,ongoing climate change will likely exacerbate their impact.In this study,we applied species distribution modeling techniques to identify poten-tial substitutive species for sweet chestnut in the light of future climate scenarios SSP126 and SSP370 in southern Switzerland.Using the presence-only machine learning algorithm MaxEnt and leveraging occurrence data from the global dataset GBIF,we delineated the current and projected(2070-2100)distribution of 28 tree species.Several exotic species emerged as valuable alternatives to sweet chestnut,although careful consideration of all potential ecological consequences is required.We also identified several native tree species as promising substitutes,offering ecological benefits and potential adaptability to climatic conditions.Since species diversification fosters forest resilience,we also determined communities of alternative species that can be grown together.Our findings represent a valuable deci-sion tool for forest managers confronted with the challenges posed by ink disease and climate change.Given that,even in absence of disease,sweet chestnut is not a future-proof tree species in the study region,the identified species could offer a pathway toward resilient and sustainable forests within the entire chestnut belt. 展开更多
关键词 Invasive pathogens tree distribution modeling Climate change Forest area
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A quantitative framework for tree-soil interaction mechanisms in expansive clay:Field investigation and empirical modeling
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作者 Xi Sun Jie Li +2 位作者 You Gao Xin Liu Annan Zhou 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第8期5155-5169,共15页
The complex behaviors of expansive soils,particularly their volumetric changes driven by moisture variations,pose significant challenges in urban geotechnical engineering.Although vegetation-induced moisture changes a... The complex behaviors of expansive soils,particularly their volumetric changes driven by moisture variations,pose significant challenges in urban geotechnical engineering.Although vegetation-induced moisture changes are known to affect ground movement,quantitative characterization of tree–soil interactions remains limited due to insufficient field data and unclear relationships between tree water uptake and soil response.This study investigates the mechanical behavior of expansive clay soils influenced by two Lophostemon confertus samples during a 14-month field monitoring program in Melbourne,Australia.The research methodology integrates measurements of soil displacement,total soil suction,moisture content,and tree water consumption through instrumentation and monitoring systems.Field measurements suggest that tree roots reached the limits of their water extraction capacity when total soil suction exceeded 2880 kPa within the active root zone.The spatial extent of tree-induced soil desiccation reached 0.6–0.7 times the tree height laterally and penetrated to depths of 2.5–3.3 m vertically.The mature sample,with an 86%greater crown area and a threefold larger sapwood area,exhibited 142%higher water consumption(35 kL),demonstrating the scalability of tree–soil interaction mechanisms.A multiple linear regression model was developed to quantify the coupled relationships between soil movement and key variables,achieving a high adjusted R2 value of 0.97,which provides engineers and practitioners with a practical tool for estimating ground movement near trees.These findings offer valuable insights for infrastructure design in tree-adjacent environments and can inform computational models and design codes to enable more accurate site assessments and sustainable urban development. 展开更多
关键词 Empirical model Expansive soil Ground movement Soil suction Soil water dynamics tree root–soil interaction
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Mixed-effects modeling for tree height prediction models of Oriental beech in the Hyrcanian forests 被引量:9
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作者 Siavash Kalbi Asghar Fallah +2 位作者 Pete Bettinger Shaban Shataee Rassoul Yousefpour 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第5期1195-1204,共10页
Height–diameter relationships are essential elements of forest assessment and modeling efforts.In this work,two linear and eighteen nonlinear height–diameter equations were evaluated to find a local model for Orient... Height–diameter relationships are essential elements of forest assessment and modeling efforts.In this work,two linear and eighteen nonlinear height–diameter equations were evaluated to find a local model for Oriental beech(Fagus orientalis Lipsky) in the Hyrcanian Forest in Iran.The predictive performance of these models was first assessed by different evaluation criteria: adjusted R^2(R^2_(adj)),root mean square error(RMSE),relative RMSE(%RMSE),bias,and relative bias(%bias) criteria.The best model was selected for use as the base mixed-effects model.Random parameters for test plots were estimated with different tree selection options.Results show that the Chapman–Richards model had better predictive ability in terms of adj R^2(0.81),RMSE(3.7 m),%RMSE(12.9),bias(0.8),%Bias(2.79) than the other models.Furthermore,the calibration response,based on a selection of four trees from the sample plots,resulted in a reduction percentage for bias and RMSE of about 1.6–2.7%.Our results indicate that the calibrated model produced the most accurate results. 展开更多
关键词 Random effects tree height CALIBRATION Sangdeh forest Chapman–Richards model Oriental beech
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Complementary parametric probit regression and nonparametric classi?cation tree modeling approaches to analyze factors affecting severity of work zone weather-related crashes 被引量:2
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作者 Ali Ghasemzadeh Mohamed M.Ahmed 《Journal of Modern Transportation》 2019年第2期129-140,共12页
Identifying risk factors for road traffic injuries can be considered one of the main priorities of transportation agencies. More than 12,000 fatal work zone crashes were reported between 2000 and 2013. Despite recent ... Identifying risk factors for road traffic injuries can be considered one of the main priorities of transportation agencies. More than 12,000 fatal work zone crashes were reported between 2000 and 2013. Despite recent efforts to improve work zone safety, the frequency and severity of work zone crashes are still a big concern for transportation agencies. Although many studies have been conducted on different work zone safety-related issues, there is a lack of studies that investigate the effect of adverse weather conditions on work zone crash severity. This paper utilizes probit–classification tree, a relatively recent and promising combination of machine learning technique and conventional parametric model, to identify factors affecting work zone crash severity in adverse weather conditions using 8 years of work zone weatherrelated crashes (2006–2013) in Washington State. The key strength of this technique lies in its capability to alleviate the shortcomings of both parametric and nonparametric models. The results showed that both presence of traffic control device and lighting conditions are significant interacting variables in the developed complementary crash severity model for work zone weather-related crashes. Therefore, transportation agencies and contractors need to invest more in lighting equipment and better traffic control strategies at work zones, specifically during adverse weather conditions. 展开更多
关键词 ADVERSE WEATHER Work zone Safety CRASH characteristics PROBIT model Decision tree
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The growth and production modeling of individual trees of Eucalyptus urophylla plantations 被引量:1
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作者 Joao Victor Nobre Carrijo Ana Beatriz de Freitas Ferreira +4 位作者 Marcela Costa Ferreira Mario Cesar de Aguiar Eder Pereira Miguel Eraldo Aparecido Trondoli Matricardi Alba Valeria Rezende 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第5期1663-1672,共10页
Individual tree models(ITMs)are classified as growth and production models for projecting current and future forest stands.ITMs are more complex than other growth and production models,show a higher level of detail an... Individual tree models(ITMs)are classified as growth and production models for projecting current and future forest stands.ITMs are more complex than other growth and production models,show a higher level of detail and,consequently,produce a better modeling resolution.However,the accuracy and efficiency of ITMs have not been properly assessed to date.In this study,we estimated the growth in height,diameter,and individual tree volume of a Eucalyptus urophylla plantation by applying an ITM.We used a continuing forest inventory dataset in which 1554 individual trees within 29 permanent plots were measured in the field over a 6-year period(24 to 72 months).Each individual tree volume was estimated for future tree age.To achieve this,we adjusted the model to predict the height and diameter growth,and the probability of mortality as a function of the competition index.The ITM accuracy was assessed based on the analysis of variance results and,subsequently,the multiple mean comparison test at the 5%significance level.The tree volumes predicted by the ITM for the forest stand aged 72 months,beginning at ages 24,36,48,and 60 months,were compared to the field measured tree volume acquired from the 72-month forest inventory that was used as the reference age.Estimated and observed tree volumes were similar when the estimation was based on the 48-month forest plots.These results might help to reduce financial costs of forest inventory because the ITM produces accurate future predictions of forest stand stocks.Our estimated ITM for Eucalyptus plantations using measurement intervals up to 2 years is recommended because it significantly reduced the projected volume discrepancy compared to the field measurements. 展开更多
关键词 Competition index Forest production Forest site Simulation models tree mortality
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Automated soil resources mapping based on decision tree and Bayesian predictive modeling 被引量:1
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作者 周斌 张新刚 王人潮 《Journal of Zhejiang University Science》 EI CSCD 2004年第7期782-795,共14页
This article presents two approaches for automated building of knowledge bases of soil resources mapping. These methods used decision tree and Bayesian predictive modeling, respectively to generate knowledge from tra... This article presents two approaches for automated building of knowledge bases of soil resources mapping. These methods used decision tree and Bayesian predictive modeling, respectively to generate knowledge from training data. With these methods, building a knowledge base for automated soil mapping is easier than using the conventional knowledge acquisition approach. The knowledge bases built by these two methods were used by the knowledge classifier for soil type classification of the Longyou area, Zhejiang Province, China using TM bi-temporal imageries and GIS data. To evaluate the performance of the resultant knowledge bases, the classification results were compared to existing soil map based on field survey. The accuracy assessment and analysis of the resultant soil maps suggested that the knowledge bases built by these two methods were of good quality for mapping distribution model of soil classes over the study area. 展开更多
关键词 Soil mapping Decision tree Bayesian predictive modeling Knowledge-based classification Rule extracting
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Statistical Modeling with a Hidden Markov Tree and High-resolution Interpolation for Spaceborne Radar Reflectivity in the Wavelet Domain 被引量:1
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作者 Leilei KOU Yinfeng JIANG +1 位作者 Aijun CHEN Zhenhui WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第12期1359-1374,共16页
With the increasing availability of precipitation radar data from space,enhancement of the resolution of spaceborne precipitation observations is important,particularly for hazard prediction and climate modeling at lo... With the increasing availability of precipitation radar data from space,enhancement of the resolution of spaceborne precipitation observations is important,particularly for hazard prediction and climate modeling at local scales relevant to extreme precipitation intensities and gradients.In this paper,the statistical characteristics of radar precipitation reflectivity data are studied and modeled using a hidden Markov tree(HMT)in the wavelet domain.Then,a high-resolution interpolation algorithm is proposed for spaceborne radar reflectivity using the HMT model as prior information.Owing to the small and transient storm elements embedded in the larger and slowly varying elements,the radar precipitation data exhibit distinct multiscale statistical properties,including a non-Gaussian structure and scale-to-scale dependency.An HMT model can capture well the statistical properties of radar precipitation,where the wavelet coefficients in each sub-band are characterized as a Gaussian mixture model(GMM),and the wavelet coefficients from the coarse scale to fine scale are described using a multiscale Markov process.The state probabilities of the GMM are determined using the expectation maximization method,and other parameters,for instance,the variance decay parameters in the HMT model are learned and estimated from high-resolution ground radar reflectivity images.Using the prior model,the wavelet coefficients at finer scales are estimated using local Wiener filtering.The interpolation algorithm is validated using data from the precipitation radar onboard the Tropical Rainfall Measurement Mission satellite,and the reconstructed results are found to be able to enhance the spatial resolution while optimally reproducing the local extremes and gradients. 展开更多
关键词 spaceborne precipitation radar hidden Markov tree model Gaussian mixture model interpolation in the wavelet domain multiscale statistical properties
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On-Street Parking Space Detection Using YOLO Models and Recommendations Based on KD-Tree Suitability Search
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作者 Ibrahim Yahaya Garta William Eric Manongga +1 位作者 Su-Wen Huang Rung-Ching Chen 《Computers, Materials & Continua》 2025年第12期4457-4471,共15页
Unlike the detection of marked on-street parking spaces,detecting unmarked spaces poses significant challenges due to the absence of clear physical demarcation and uneven gaps caused by irregular parking.In urban citi... Unlike the detection of marked on-street parking spaces,detecting unmarked spaces poses significant challenges due to the absence of clear physical demarcation and uneven gaps caused by irregular parking.In urban cities with heavy traffic flow,these challenges can result in traffic disruptions,rear-end collisions,sideswipes,and congestion as drivers struggle to make decisions.We propose a real-time detection system for on-street parking spaces using YOLO models and recommend the most suitable space based on KD-tree search.Lightweight versions of YOLOv5,YOLOv7-tiny,and YOLOv8 with different architectures are trained.Among the models,YOLOv5s with SPPF at the backbone achieved an F1-score of 0.89,which was selected for validation using k-fold cross-validation on our dataset.The Low variance and standard deviation recorded across folds indicate the model’s generalizability,reliability,and stability.Inference with KD-tree using predictions from the YOLO models recorded FPS of 37.9 for YOLOv5,67.2 for YOLOv7-tiny,and 67.0 for YOLOv8.The models successfully detect both marked and unmarked empty parking spaces on test data with varying inference speeds and FPS.These models can be efficiently deployed for real-time applications due to their high FPS,inference speed,and lightweight nature.In comparison with other state-of-the-art models,our models outperform them,further demonstrating their effectiveness. 展开更多
关键词 On-street parking YOLO models K-dimensional tree K-fold cross-validation
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Modelling tree volume for a tropical rainforest in Okomu National Park, Edo State, Nigeria
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作者 H.I.Aigbe D.H.Japheth U.E.Ekwugha 《Journal of Forestry Research》 2025年第4期189-203,共15页
Volume models for the long-term management of Okomu National Park in Nigeria are not available. The main challenge in assessing forest resources is the lack of accurate, species-specific baseline data and updated info... Volume models for the long-term management of Okomu National Park in Nigeria are not available. The main challenge in assessing forest resources is the lack of accurate, species-specific baseline data and updated information on volume models, growth rates, and disturbances. This complicates the development of effective management plans. This study addresses this by modelling tree volume using temporary sample plots laid out using a systematic line transect method Data was collected from 16 40 m × 50 m plots using a Spiegel relascope. DBH, top, middle, and base diameters, and overall height were measured for trees ≤ 10 cm DBH. Newton’s formula calculated volume of each tree, and per hectare estimates generated. The results showed an average of 132 trees per hectare. Population densities of individual species ranged from 1–11/ha, indicating a low density. Strombosia pustulata was the most abundant species. For coefficients that form the basis for species grouping, species-specific volume equations were developed and grouped into three clusters. Regression equations were fitted and selected based on specific statistical metrics. The volume models showed that generalized (V_(i)=b_(0)+b_(1)(D_(i)^(2)H_(i))+ε_(i)) functions, based on the statistical metrics, performed more effectively. The generalized functions exhibited superior performance, evidenced by the uniform residual plot distribution for DBH^(2)H, implying consistent experimental error and adherence to regression assumptions. A t-test at 95% confidence showed that the discrepancy between predicted and actual values was insignificant. This study indicates that the prediction models provide effective management tools for climate mitigation and determining carbon sequestration by a tropical forest. 展开更多
关键词 modelLING Volume equations Tropical rainforest Okomu National Park tree species
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Author Correction:Generation of a tree shrew breast cancer model using lentivirus expressing PIK3CA-H1047R
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作者 Li Zeng Hong-Yan Zhang +6 位作者 Chuan-Yu Yang Zhuo Cheng Qiu-Yun Jiang Yao Luo Yi Li Fu-Bing Li Ce-Shi Chen 《Zoological Research》 2025年第2期312-312,共1页
Following the publication of Zeng et al.(2023),an inadvertent error was recently identified in Figure 1B and Supplementary Figure S3.To ensure the accuracy and integrity of our published work,we formally request a cor... Following the publication of Zeng et al.(2023),an inadvertent error was recently identified in Figure 1B and Supplementary Figure S3.To ensure the accuracy and integrity of our published work,we formally request a correction to address this issue and apologize for any confusion this error may have caused.For details,please refer to the modified Supplementary Materials. 展开更多
关键词 LENTIVIRUS pik3ca-h1047r CORRECTION inadvertent error ERROR modified supplementary materials breast cancer model tree shrew
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基于i-Tree Eco模型的城市森林生态效益评估——以兰州市建成区为例
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作者 韩雷 唐红 +3 位作者 陶宣霖 杨笑寒 丁礼威 陈飞洋 《中南林业科技大学学报》 北大核心 2026年第1期158-169,共12页
[目的]针对西北高海拔寒旱地区城市森林生态效益评估不足的问题,以兰州市建成区为研究对象,旨在通过i-Tree Eco模型构建多维度生态效益评估框架,揭示城市森林在碳汇、水文调节及空气污染物去除等生态效益中的贡献,为干旱区城市森林配置... [目的]针对西北高海拔寒旱地区城市森林生态效益评估不足的问题,以兰州市建成区为研究对象,旨在通过i-Tree Eco模型构建多维度生态效益评估框架,揭示城市森林在碳汇、水文调节及空气污染物去除等生态效益中的贡献,为干旱区城市森林配置优化与生态效益提升提供科学依据。[方法]采用i-Tree Eco模型,整合实地植被调查数据、地理和气象等多源数据,对兰州市建成区城市森林生态效益进行评估。将碳封存、氧气释放、空气质量改善、雨水截留和节能等方面的生态效益量化为经济效益,并筛选出生态效益高的乔灌木树种;构建生态效益-经济投入耦合模型,分析不同乔灌木配置比例对生态效益的影响。[结果]1)兰州市建成区城市森林年生态效益约为2.96亿元,单株乔灌木年生态效益分别为211.42元、13.89元;2)城市森林年碳封存约为32 111.46 t,释放的氧气约为85 692.86 t,截留的雨水约为5 686 379.93 m^(3),移除的空气污染物约为876.60 t,能源上节省了约1 300.99万元;3)将乔灌木配置比例调整至7∶13时,达到生态效益与经济投入的最优平衡,使年生态效益增加约2 900万元;4)在单株生态效益的比较中,国槐、臭椿、七叶树、侧柏、圆柏等乔木表现出较高的生态效益,金银忍冬、珍珠梅、冬青卫矛、铺地柏、木槿等灌木在生态效益方面表现良好,建议在城市森林建设中优先推广这些优势树种。[结论]乔木对生态效益的贡献显著高于灌木;不同树种间生态效益呈现显著梯度差异;通过优化乔灌木配置比例,可在有限成本下实现生态效益最大化。研究结果为城市森林“增汇-减排-节水-节能”一体化规划提供可推广范式。 展开更多
关键词 兰州市 城市森林 生态效益 i-tree Eco模型
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Modeling for Underground Cable Water Tree Growth Dynamics
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作者 Sola Famakin Charles Kim 《Journal of Power and Energy Engineering》 2019年第12期51-65,共15页
Underground cable faults, whether transient or permanent, are traceable to in-sulation failure problems, most of which are water tree initiated. Insulation breakdown, which usually leads to costly power outages, may b... Underground cable faults, whether transient or permanent, are traceable to in-sulation failure problems, most of which are water tree initiated. Insulation breakdown, which usually leads to costly power outages, may be prevented by taking pre-emptive actions. The most decisive pre-emptive action is one in which real-time tracking of water tree advancement within the cable insulation system is possible. Such pre-emptive actions, however, depend on accurate modeling of the phenomenon. Earlier water tree models are static in that they focused on the cable insulation property change at a time segment. Thus, they lack the properties needed for tracking water tree progress and for determining the onset of transient and permanent faults. This paper presents a new ap-proach to water tree modeling, focused on insulation degradation geometry in the form of parabolic expansion of water tree. We developed a dynamic model centered on the computation of the capacitance of a vented water tree as a function of time. The dynamic model accounts for the time-dependence of the radial growth of the water tree to track insulation degradation. The model was tested in predicting cross-linked polyethylene (XLPE) cable’s insulation lifespan. The result was found to be within the range of the recorded lifespan of field aged cables in the literature. Also, performance comparison with an earlier analytical model validated with COMSOL Hyperphysics software shows a signif-icant correlation between them. 展开更多
关键词 INSULATION modeling treeing CAPACITANCE PERMITTIVITY
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Ethnographic Decision Tree Modeling of the Decision Criteria and Decision Patterns for Adult Married Women with Unexpected Pregnancies
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作者 Yu-Chan Li Yieh Loong Tsai Pei-Jung Lan 《Open Journal of Obstetrics and Gynecology》 2017年第10期1052-1063,共12页
Introduction: As far as adult and married women were concerned, when they occurred to “unplanned pregnancy”, they felt so surprised and concussive all the time. Besides, the unplanned pregnancy also affects the othe... Introduction: As far as adult and married women were concerned, when they occurred to “unplanned pregnancy”, they felt so surprised and concussive all the time. Besides, the unplanned pregnancy also affects the other members in the family system. Therefore, when married women have to face the choice: “birth” or “abortion”, they’ll consider lots of thoughts and different decision criteria and decision pattern under various influences on physician, mind, mental and society. The purpose of this study was to investigate the criteria considered and the decision patterns involved when adult married women decide whether to terminate or continue an unplanned pregnancy. Methods: The study uses the method—“Ethnographic Decision Tree Modeling” [1] to build model of the decision criteria and decision patterns involved when adult married women make a decision about their unplanned pregnancy. There are three process in the research method: “Pilot Study”—interview two groups, every group distinct 4 married adult women with unplanned pregnancies, which decide whether to terminate or continue an unplanned pregnancy, what is the items of decision characters affect to the choice: “birth” or “abortion”. “Building of the Model”, displays the importance in proper order of those items and build the modeling with these two groups of women. “Testing of the Model”: investigate the criteria considered and the decision patterns involved when adult married women decide whether to terminate or continue an unplanned pregnancy. The study interviewed 34 married adult women with 43 unplanned pregnancies totally. Results: The result of the study finds out 12 items of decision characters, including planning to get pregnant or not, stability of feelings for married partner, the points of view on life, was affected by mother, mother-in-law, an husband’s emphasis on male, the meanings of children, the financial burden, the plan an assignment of career and time, the past pregnant experiences, the status of raising children, the health of parents and fetus, the effect of living environment, and social and cultural vision. Besides, there are four decision patterns of married adult women with unplanned pregnancy are “receiving abortion positively”;“giving birth as long as getting pregnancy naturally”;“ the minds are hesitative and changeable”, and “being forced by important others.” Conclusion: By setting the decision model tree, we found several decision criteria and patterns, and possible modes actions to be taken, could offer to see the adult married women’s decision-making and struggles in mind about unplanned pregnancy. 展开更多
关键词 Ethnographic DECISION tree modeling ADULT and MARRIED Women UNPLANNED Pregnancy DECISION Pattern
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Botanical tree reconstruction from a single image via 3D GAN-based skeletonization
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作者 Chi Weng MA Ruien SHEN +1 位作者 Deli DONG Shuangjiu XIAO 《虚拟现实与智能硬件(中英文)》 2026年第1期101-114,共14页
Background 3D botanical tree reconstruction from a single image plays a vital role in the field of computer graphics.However,accurately capturing the intricate branching patterns and detailed morphologies of trees rem... Background 3D botanical tree reconstruction from a single image plays a vital role in the field of computer graphics.However,accurately capturing the intricate branching patterns and detailed morphologies of trees remains a challenge.Methods In this study,we proposed a novel approach for single-image tree reconstruction using a conditional generative adversarial network to infer the 3D skeleton of a tree in the form of a 2D skeleton depth map.Based on the 2D skeleton depth map,a corresponding branching structure(3D skeleton)that inherits the tree shape in the input image and leaves can be generated using a procedural modeling technique.Result Experimental results show that the proposed method accurately reconstructs diverse tree structures across species.Both quantitative and qualitative evaluations demonstrate improved skeleton completeness,branching accuracy,and visual realism over baseline methods,while requiring no user input.Conclusions Our proposed approach for generating lifelike 3D tree models from a single image with no user input shows its proficiency in achieving efficient and reliable reconstruction.These results showcase the capability of the proposed model to recreate complex tree architectures while capturing their visual authenticity. 展开更多
关键词 tree reconstruction Procedural modeling Plant modeling SKELETONIZATION Deep learning
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Saturating allometric relationships reveal how wood density shapes global tree architecture
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作者 Thi Duyen Nguyen Masatoshi Katabuchi 《Journal of Forestry Research》 2026年第1期111-124,共14页
Allometric equations are fundamental tools in ecological research and forestry management,widely used for estimating above-ground biomass and production,serving as the core foundations of dynamic vegetation models.Usi... Allometric equations are fundamental tools in ecological research and forestry management,widely used for estimating above-ground biomass and production,serving as the core foundations of dynamic vegetation models.Using global datasets from Tallo(a tree allometry and crown architecture database encompassing thousands of species)and TRY(a plant traits database),we fit B ayesian hierarchical models with three alternative functional forms(powerlaw,generalized Michaelis-Menten(gMM),and Weibull)to characterize how diameter at breast height(DBH),tree height(H),and crown radius(CR)scale with and without wood density as a species-level predictor.Our analysis revealed that the saturating Weibull function best captured the relationship between tree height and DBH in both functional groups,whereas the CR-DBH relationship was best predicted by a power-law function in angiosperms and by the gMM function in gymnosperms.Although including wood density did not significantly improve predictive performance,it revealed important ecological trade-offs:lighter-wood angiosperms achieve taller mature heights more rapidly,and denser wood promotes wider crown expansion across clades.We also found that accurately estimating DBH required considering both height and crown size,highlighting how these variables together distinguish trees of similar height but differing trunk diameters.Our results emphasize the importance of applying saturating functions for large trees to improve forest biomass estimates and show that wood density,though not always predictive at broad scales,helps illuminate the biomechanical and ecological constraints underlying diverse tree architectures.These findings offer practical pathways for integrating height-and crown-based metrics into existing carbon monitoring programs worldwide. 展开更多
关键词 Above ground biomass Crown radius Diameter at breast height tree allometry model tree height Wood density
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Optimization models of stand structure and selective cutting cycle for large diameter trees of broadleaved forest in Changbai Mountain 被引量:6
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作者 郝清玉 周玉萍 +1 位作者 王立海 吴金卓 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第2期135-140,共6页
The optimum models of harvesting yield and net profits of large diameter trees for broadleaved forest were developed, of which include matrix growth sub-model, harvesting cost and wood price sub-models, based on the d... The optimum models of harvesting yield and net profits of large diameter trees for broadleaved forest were developed, of which include matrix growth sub-model, harvesting cost and wood price sub-models, based on the data from Hongshi Forestry Bureau, in Changbai Mountain region, Jilin Province, China. The data were measured in 232 permanent sample plots. With the data of permanent sample plots, the parameters of transition probability and ingrowth models were estimated, and some models were compared and partly modified. During the simulation of stand structure, four factors such as largest diameter residual tree (LDT), the ratio of the number of trees in a given diameter class to those in the next larger diameter class (q), residual basal area (RBA) and selective cutting cycle (C) were considered. The simulation results showed that the optimum stand structure parameters for large diameter trees are as follows: q is 1.2, LDT is 46cm, RBA is larger than 26 m^2 and selective cutting cycle time (C) is between 10 and 20 years. 展开更多
关键词 Large diameter tree Stand structure OPTIMIZATION Broad-leaved forest model
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Tree shrew (Tupaia belangeri)as a novel laboratory disease animal model 被引量:44
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作者 Ji Xiao Rong Liu Ce-Shi Chen 《Zoological Research》 CAS CSCD 2017年第3期127-137,共11页
The tree shrew (Tupaia belangeri) is a promising laboratory animal that possesses a closer genetic relationship to primates than to rodents. In addition, advantages such as small size, easy breeding, and rapid repro... The tree shrew (Tupaia belangeri) is a promising laboratory animal that possesses a closer genetic relationship to primates than to rodents. In addition, advantages such as small size, easy breeding, and rapid reproduction make the tree shrew an ideal subject for the study of human disease. Numerous tree shrew disease models have been generated in biological and medical studies in recent years. Here we summarize current tree shrew disease models, including models of infectious diseases, cancers, depressive disorders, drug addiction, myopia, metabolic diseases, and immune-related diseases. With the success of tree shrew transgenic technology, this species will be increasingly used in biological and medical studies in the future. 展开更多
关键词 tree shrew (Tupaia belangeri) Animal model TRANSGENIC DISEASE
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Creating animal models, why not use the Chinese tree shrew ( Tupaia belangeri chinensis)? 被引量:41
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作者 Yong-Gang Yao 《Zoological Research》 CAS CSCD 2017年第3期118-126,共9页
The Chinese tree shrew (Tupaia belangeri chinensis) a squirrel-like and rat-sized mammal, has a wide distribution in Southeast Asia, South and Southwest China and has many unique characteristics that make it suitabl... The Chinese tree shrew (Tupaia belangeri chinensis) a squirrel-like and rat-sized mammal, has a wide distribution in Southeast Asia, South and Southwest China and has many unique characteristics that make it suitable for use as an experimental animal. There have been many studies using the tree shrew (Tupaia belangeri) aimed at increasing our understanding of fundamental biological mechanisms and for the modeling of human diseases and therapeutic responses. The recent release of a publicly available annotated genome sequence of the Chinese tree shrew and its genome database (www.treeshrewdb.org) has offered a solid base from which it is possible to elucidate the basic biological properties and create animal models using this species. The extensive characterization of key factors and signaling pathways in the immune and nervous systems has shown that tree shrews possess both conserved and unique features relative to primates. Hitherto, the tree shrew has been successfully used to create animal models for myopia, depression, breast cancer, alcohol-induced or non-alcoholic fatty liver diseases, herpes simplex virus type 1 (HSV-1) and hepatitis C virus (HCV) infections, to name a few. The recent successful genetic manipulation of the tree shrew has opened a new avenue for the wider usage of this animal in biomedical research. In this opinion paper, I attempt to summarize the recent research advances that have used the Chinese tree shrew, with a focus on the new knowledge obtained by using the biological properties identified using the tree shrew genome, a proposal for the genome-based approach for creating animal models, and the genetic manipulation of the tree shrew. With more studies using this species and the application of cutting-edge gene editing techniques, the tree shrew will continue to be under the spot light as a viable animal model for investigating the basis of many different human diseases. 展开更多
关键词 Chinese tree shrew Genome biology Animal model Gene editing Innate immunity
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Mapping landslide susceptibility at the Three Gorges Reservoir, China, using gradient boosting decision tree,random forest and information value models 被引量:14
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作者 CHEN Tao ZHU Li +3 位作者 NIU Rui-qing TRINDER C John PENG Ling LEI Tao 《Journal of Mountain Science》 SCIE CSCD 2020年第3期670-685,共16页
This work was to generate landslide susceptibility maps for the Three Gorges Reservoir(TGR) area, China by using different machine learning models. Three advanced machine learning methods, namely, gradient boosting de... This work was to generate landslide susceptibility maps for the Three Gorges Reservoir(TGR) area, China by using different machine learning models. Three advanced machine learning methods, namely, gradient boosting decision tree(GBDT), random forest(RF) and information value(InV) models, were used, and the performances were assessed and compared. In total, 202 landslides were mapped by using a series of field surveys, aerial photographs, and reviews of historical and bibliographical data. Nine causative factors were then considered in landslide susceptibility map generation by using the GBDT, RF and InV models. All of the maps of the causative factors were resampled to a resolution of 28.5 m. Of the 486289 pixels in the area,28526 pixels were landslide pixels, and 457763 pixels were non-landslide pixels. Finally, landslide susceptibility maps were generated by using the three machine learning models, and their performances were assessed through receiver operating characteristic(ROC) curves, the sensitivity, specificity,overall accuracy(OA), and kappa coefficient(KAPPA). The results showed that the GBDT, RF and In V models in overall produced reasonable accurate landslide susceptibility maps. Among these three methods, the GBDT method outperforms the other two machine learning methods, which can provide strong technical support for producing landslide susceptibility maps in TGR. 展开更多
关键词 MAPPING LANDSLIDE SUSCEPTIBILITY Gradient BOOSTING DECISION tree Random forest Information value model Three Gorges Reservoir
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Growth simulation and yield prediction for perennial jujube fruit tree by integrating age into the WOFOST model 被引量:8
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作者 BAI Tie-cheng WANG Tao +2 位作者 ZHANG Nan-nan CHEN You-qi Benoit MERCATORIS 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第3期721-734,共14页
Mathematical models have been widely employed for the simulation of growth dynamics of annual crops,thereby performing yield prediction,but not for fruit tree species such as jujube tree(Zizyphus jujuba).The objective... Mathematical models have been widely employed for the simulation of growth dynamics of annual crops,thereby performing yield prediction,but not for fruit tree species such as jujube tree(Zizyphus jujuba).The objectives of this study were to investigate the potential use of a modified WOFOST model for predicting jujube yield by introducing tree age as a key parameter.The model was established using data collected from dedicated field experiments performed in 2016-2018.Simulated growth dynamics of dry weights of leaves,stems,fruits,total biomass and leaf area index(LAI) agreed well with measured values,showing root mean square error(RMSE) values of 0.143,0.333,0.366,0.624 t ha^-1 and 0.19,and R2 values of 0.947,0.976,0.985,0.986 and 0.95,respectively.Simulated phenological development stages for emergence,anthesis and maturity were 2,3 and 3 days earlier than the observed values,respectively.In addition,in order to predict the yields of trees with different ages,the weight of new organs(initial buds and roots) in each growing season was introduced as the initial total dry weight(TDWI),which was calculated as averaged,fitted and optimized values of trees with the same age.The results showed the evolution of the simulated LAI and yields profiled in response to the changes in TDWI.The modelling performance was significantly improved when it considered TDWI integrated with tree age,showing good global(R2≥0.856,RMSE≤0.68 t ha^-1) and local accuracies(mean R2≥0.43,RMSE≤0.70 t ha^-1).Furthermore,the optimized TDWI exhibited the highest precision,with globally validated R2 of 0.891 and RMSE of 0.591 t ha^-1,and local mean R2 of 0.57 and RMSE of 0.66 t ha^-1,respectively.The proposed model was not only verified with the confidence to accurately predict yields of jujube,but it can also provide a fundamental strategy for simulating the growth of other fruit trees. 展开更多
关键词 fruit tree growth simulation yield forecasting crop model tree age
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