检索结果-南通市图书馆

Simulating Site-Specific Effects of a Changing Climate on Jack Pine Productivity Using a Modified Variant of the CROPLANNER Model

引用

Open Journal of Forestry 2012年第1期2卷 23-32页

作者： peter F. newton 不详

This study evaluated the site-specific effects of projected future climate conditions on the productivity of jack pine (Pinus banksiana Lamb.) plantations over the next 50 years (2011-2061). Climatic parameters as predicted by the Canadian Global Climate Model in association with a regional spatial climatic model, under 3 emissions scenarios (no change (NC), B1 and A2), were used as input values to a biophysical-based site-specific height-age model that was integrated into the CROPLANNER model and associated algorithm. Plantations managed under a basic silvicultural intensity on two site qualities at each of two geographically separated sites (northeastern and northwestern Ontario, Canada) were assessed. The results indicated that the stands situated on low-to-medium quality sites at both locations were largely unaffected by the predicted increase in temperature and precipitation rates. Conversely, however, stands situated on good-to-excellent quality sites grown under the B1 and A2 scenarios experienced consequential declines in stand development rates resulting in decreases in rotational mean sizes, biomass yields, recoverable end-product volumes, and economic worth. In addition to providing a plausible range of site-specific climate change outcomes on jack pine productivity within the central portion of the species range, these results suggest that future predictions that do not account for potential climate changes effects may overes- timate merchantable productivity on the higher site qualities by approximately 15%. As demonstrated, in- corporating biophysical-based site index functions within existing forest productivity models may repre- sent a feasible approach when accounting for climate change effects on yield outcomes of boreal species.

关键词： B1 and A2 Emission Scenarios Low-to-Medium and Good-to-Excellent Site Qualities Basic Silvicultural Intensity Regimes

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Quantifying Growth Responses of Black Spruce and Jack Pine to Thinning within the Context of Density Management Decision-Support Systems

引用

Open Journal of Forestry 2015年第4期5卷 409-421页

作者： peter F. newton Canadian Wood Fibre Centre Canadian Forest Service Natural Resources Canada Sault Ste. Marie Canada

Models for quantifying the growth responses of black spruce (Picea mariana (Mill) BSP.) and jack pine (Pinus banksiana Lamb.) to precommercial thinning (PCT) treatments were developed. They accounted for the increased rate of stand development arising from PCT treatments through temporal adjustments to the species and site specific mean dominant height-age functions. Analytically, they utilized a relative height growth modifier consistent with observed density-dependent height repression effects. A phenotypic juvenile age-mature age correlation function was used to account for the intrinsic temporal decline in the magnitude of the PCT effect throughout the rotation. The resultant stand development patterns were in accord with theoretical and empirical expectations when the response models were integrated into algorithmic variants of structural stand density management models.

关键词： Structural Stand Density Management Models Height Repression Phenotypic Juvenile Age-Mature age Correlation Precommercial Thinning

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Genetic Worth Effect Models for Boreal Conifers and Their Utility When Integrated into Density Management Decision-Support Systems

引用

Open Journal of Forestry 2015年第1期5卷 105-115页

作者： peter F. newton Canadian Wood Fibre Centre Canadian Forest Service Natural Resources Canada Sault Ste. Marie Canada

Based on approaches deduced from previous research findings and empirical observations from density control experiments, genetic worth effect response models were developed for black spruce (Picea mariana (Mill) BSP.) and jack pine (Pinus banksiana Lamb.) plantations. The models accounted for the increased rate of stand development arising from the planting of genetically-improved stock through temporal adjustments to the species-specific site-based mean dominant height-age functions. The models utilized a relative height growth modifier based on known estimates of genetic gain. The models also incorporated a phenotypic juvenile age-mature age correlation function in order to account for the intrinsic temporal decline in the magnitude of genetic worth effects throughout the rotation. Integrating the functions into algorithmic variants of structural stand density management models produced stand development patterns that were consistent with axioms of even-aged stand dynamics.

关键词： Picea mariana Pinus banksiana Structural Stand Density Management Models Phenotypic Juvenile Age-Mature Age Correlation Canadian Boreal Forest Region

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Physical and chemical characterization of sediments from an Andean river exposed to mining and agricultural activities: The Moquegua River, Peru

引用

International Journal of Sediment Research 2022年第6期37卷 780-793页

作者： Luis de Los Santos Valladares Juan Luis Ccamapaza Renato Arturo Valencia-Bedregal Luis Enrique Borja-Castro Jose Velazquez-Garcia Dehiwalage Harshani Nimalika Perera Adrian Ionescu David Arvidsson Eustace Peregrine Barnes peter newton Hugo Lepage Patrick Byrne Angel Guillermo Bustamante Dominguez Crispin H.W.Barnes Cavendish Laboratory Department of Physics University of Cambridge Escuela Acad emico Profesional de Ingeniería Ambiental Universidad Nacional de Moquegua Provincia de Mariscal Nieto Laboratorio de Cer amicos y Nanomateriales Facultad de Ciencias Físicas Universidad Nacional Mayor de San Marcos School of Biological and Environmental Science Liverpool John Moores University

This study presents an analysis of sediments in an Andean river impacted by both natural conditions and anthropogenic activities. Fifty samples were collected from selected sites throughout the Moquegua River drainage basin, and Tambo River headwaters at Pasto Grande, in Peru, and analysed with X-ray diffraction, energy dispersive X-ray spectroscopy, scanning electron microscopy, Fourier-transform infrared spectroscopy and thermogravimetric analysis. Si, Ca, Al, Fe, and O, common constituents of soils, were dominant, along with K, N, and P. The latter originating as primary macronutrients or chemical residuals from fertilizers used in agriculture. Higher concentrations of macronutrients and organic components were found in agricultural and urban areas, respectively. Arsenic minerals were also detected, which occur naturally, but possibly at levels augmented by anthropogenic activity. The application of cluster analysis revealed clustering between arsenic, arsenolite, and potassium but no significant geospatial correlation between sample sites in the drainage basin.

关键词： Andean river Moquegua river Sediments Fourier-transform infrared spectroscopy TG-DTG/DTA Clustering analysis

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

胸腔镜前路矫形内固定治疗特发性胸椎脊柱侧凸手术技术

引用

中华骨科杂志 2010年第3期30卷 I0041-I0054页

作者： peter O. newton, MD Vidyadhar V. Upasani, MD Juliano Lhamby, MD Valerie L. Ugrinow, BA Jeff B. Pawelek, BS Tracey P. Bastrom, MA 邱勇(译) Investigation performed at Rady Children's Hospital and Health Center San Diego California 南京鼓楼医院脊柱科 210008

背景：胸腔镜前路矫形内固定植骨融合术的患者随访2年的疗效已经有相关的研究报道，本研究的目的是评价其随访5年的结果。方法l本研究包括41例接受胸腔镜前路矫形内固定植骨融合术治疗的特发性胸椎脊柱侧凸患者，这些患者均在规定时间... 详细信息

背景：胸腔镜前路矫形内固定植骨融合术的患者随访2年的疗效已经有相关的研究报道，本研究的目的是评价其随访5年的结果。方法l本研究包括41例接受胸腔镜前路矫形内固定植骨融合术治疗的特发性胸椎脊柱侧凸患者，这些患者均在规定时间间隔随访。前瞻性收集并记录的数据包括：患者的一般资料、影像学测量、临床畸形测量、肺功能、椎体间融合评价、SRS-24评分及术前、术后的并发症。对术前、术后2年、5年的病例资料进行对比。另外，对特定的研究对象和失随访的患者术后2年的影像学测量、肺功能、SRS-24评分进行比较。

关键词：前路矫形脊柱侧凸固定治疗胸腔镜特发性手术技术胸椎影像学测量

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

The Dallas Donation after Circulatory Death Transplantation Summit:expanding donation after circulatory death procedures through process improvement,broader utilization,and innovation

引用

Hepatobiliary Surgery and Nutrition 2024年第5期13卷 824-836,I0009页

作者： Michele Finotti Anji Wall Anthony D’Alessandro Gary Schwartz Chris Sonnenday David Goldberg Ashish Shah peter Friend Jeff P.Orlowski Greg McKenna Steve newton Brad Adams William C.Chapman Amit Mathur Marwan Abouljoud Tim Pruett Amelia Hessheimer James F.Trotter Sumeet K.Asrani Giuliano Testa Simmons Transplant Institute Baylor University Medical CenterDallasTXUSA Hepatobiliary and General Surgery Unit Regional Hospital TrevisoDISCOGUniversity of PaduaPaduaItaly Division of Transplantation Department of SurgeryUniversity of Wisconsin School of Medicine and Public HealthMadisonWIUSA Department of Thoracic Surgery and Lung Transplantation Baylor University Medical CenterCenter for Advanced Heart and Lung DiseaseDallasTXUSA Department of Surgery University of MichiganAnn ArborMIUSA Division of Digestive Health and Liver Diseases Department of MedicineUniversity of Miami Miller School of MedicineMiamiFLUSA Department of Cardio-Thoracic Surgery Vanderbilt University Medical CenterNashvilleTNUSA Nuffield Department of Surgical Sciences University of OxfordOxfordUK LifeShare Transplant Donor Services of Oklahoma Oklahoma CityOKUSA Administration Baylor University Medical CenterDallasTXUSA Southwest Transplant Alliance DallasTXUSA Department of Surgery/Transplantation Washington UniversitySt.LouisMOUSA Division of Transplant Surgery Department of SurgeryMayo Clinic ArizonaAlix School of MedicinePhoenixAZUSA Divisions of Transplant and Hepatobiliary Surgery Henry Ford HospitalDetroitMIUSA Department of Surgery University of MinnesotaMinneapolisMNUSA General and Digestive Surgery Hospital Universitario La PazIdiPAZMadridSpain

Despite a significant increase in utilization over the past decade,the number of donation after circulatory death(DCD)organs that are procured and transplanted in the United States(US)remains well below its *** is still room for expansion,as utilizing DCD organs to the fullest extent is currently the most viable solution to the persistent mismatch between supply and demand in *** convened a multidisciplinary transplantation summit to examine various aspects of DCD,with faculty members from around the world with clinical and academic interest in DCD donation and transplantation,including abdominal and cardiothoracic surgeons,organ procurement organization directors,hepatologists,and *** conference focused on identifying barriers to DCD organ utilization and strategies to overcome these *** divide the barriers to DCD utilization into three mains categories:(Ⅰ)policy and process variation;(II)logistical and transportation challenges;and(Ⅲ)higher risk perceptions related to DCD *** each barrier,we proposed a variety of solutions,providing an overview of the status of DCD donation in the US and suggestions on how to increase the use of *** is a specific focus on ex situ machine perfusion,normothermic regional perfusion,and other opportunities to expand DCD utilization without negatively impacting recipient outcomes.

关键词： Donation after circulatory death donation(DCD donation) marginal graft donor pool machine perfusion(MP)

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Key features of numerical models for the FE-simulation of deep tunnel advance by the NATM

引用

Underground Space 2024年第1期14卷 357-376页

作者： peter Gamnitzer Matthias Neuner Magdalena Schreter-Fleischhacker Alexander Dummer Thomas Mader Stefan Smaniotto Gunter Hofstetter Unit of Strength of Materials and Structural Analysis Institute of Basic Sciences in Engineering SciencesUniversitat InnsbruckTechnikerstraβe 13Innsbruck A-6020Austria

In the present work,important aspects of time-dependent nonlinear 3D finite element(FE)models for deep tunnel advance by the New Austrian Tunneling Method(NATM),characterized by repeated sequences of excavation,securing,and idle periods,are discussed on the example of a 3D finite element model of a stretch of the Brenner Base Tunnel,which is currently constructed between Austria and *** material models are utilized for representing the surrounding rock mass and the shotcrete *** on the finite element model,strategies for the efficient implementation into a parallel distributed memory numerical code are *** are essential to achieve reasonable computation times for numerical simulations of tunneling based on large 3D FE *** particular,the implementation of the construction procedure,parallel computing and communication specific details,and efficient linear solvers for the global equation system within the incremental-iterative newton–Raphson scheme are ***,possible extensions of the material models for rock mass and shotcrete,used in the 3D FE model,are *** concern(i)a gradient-enhanced model for transversely isotropic rock and rock mass,taking into account hardening and softening behavior and(ii)the extension of the shotcrete model to nonlinear creep and damage due to *** possible benefits of the model extensions in numerical simulations of tunneling by the NATM are discussed.

关键词： NATM Finite element model Rock Shotcrete Damage-plasticity model

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Twelve weeks of dance exergaming in overweight and obese adolescent girls:Transfer effects on physical activity,screen time,and self-efficacy

引用

Journal of Sport and Health Science 2017年第1期6卷 4-10,127页

作者： Amanda E.Staiano Robbie A.Beyl Daniel S.Hsia peter T.Katzmarzyk Robert L.newton Jr Pennington Biomedical Research Center Baton RougeLA 70808USA

Background: Given the low levels of physical activity(PA) among adolescent girls in the US, there is a need to identify tools to motivate increased PA. Although there is limited evidence that adolescents transfer PA from one context to another, exergames(i.e., video games that require gross motor activity) may act as a gateway to promote overall PA outside game play. The purpose of this study was to examine potential transfer effects(i.e., influences on external behaviors and psychological constructs) of a 12-week exergaming intervention on adolescent girls' PA, screen time,and self-efficacy toward PA, as well as the intrinsic motivation of ***: Participants were 37 girls aged 14–18 years(65% African American, 35% white) who were overweight or obese(body mass index ≥ 85 th percentile) and were recruited from the community via school, physicians, news media, and social media websites. Adolescents were randomly assigned to a 12-week group exergaming intervention(thirty-six 60 min sessions of group-based dance exergaming in a research laboratory using Kinect for Xbox360(Microsoft Corporation, Redmond, WA, USA)) or to a no-treatment control group. Outcome variables included objectively measured PA(total) and self-reported leisure-time PA(discretionary time only) 1 week before vs. 1 week after the intervention; selected type and intensity of PA when placed in a gym setting for 30 min("cardio free choice"); screen time; self-efficacy toward PA; and intrinsic motivation toward ***: Attendance at the exergaming sessions was high(80%). Compared with the control group, the intervention group self-reported an increase in PA(p = 0.035) and fewer hours watching television or videos(p = 0.01) after the intervention, but there were no significant differences in sedentary, light, moderate, or vigorous PA measured by accelerometry. The intervention group significantly improved self-efficacy toward PA(p = 0.028). The intervention group highly rated intri

关键词： Active video games Leisure activity Motivation Screen time Self-efficacy Television

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

PARALLEL STOCHASTIC newton METHOD

引用

Journal of Computational Mathematics 2018年第3期36卷 404-425页

作者： Mojmir Mutny peter Richtarik Department of Informatics ETH Zurich Zurich Switzerland School of Mathematics University of Edinburgh Edinburgh ETH9 3FD UK Computer Electrical and Mathematical Sciences & Engineering Department KA UST Saudi Arabia

We propose a parallel stochastic newton method （PSN） for minimizing unconstrained smooth convex functions. We analyze the method in the strongly convex case, and give conditions under which acceleration can be expected when compared to its serial counterpart. We show how PSN can be applied to the large quadratic function minimization in general, and empirical risk minimization problems. We demonstrate the practical efficiency of the method through numerical experiments and models of simple matrix classes.

关键词： Optimization Parallel methods newton's method Stochastic algorithms.

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Use of Targeted Orographic Smoothing in Very High Resolution Simulations of a Downslope Windstorm and Rotor in a Sub-tropical Highland Location

引用

Advances in Atmospheric Sciences 2023年第11期40卷 2043-2062页

作者： peter SHERIDAN Anlun XU Jian LI Kalli FURTADO Met Office ExeterEX13PBUK Dali National Climate Observatory Dali 671003China State Key Laboratory of Severe Weather and Institute of Tibetan Plateau Meteorology Chinese Academy of Meteorological SciencesBeijing 100081China National Environment Agency Singapore

Nested simulations of a downslope windstorm over Cangshan mountain,Yunnan,China,have been used to demonstrate a method of topographic smoothing that preserves a relatively large amount of terrain detail compared to typical smoothing procedures required for models with terrain-following grids to run *** simulations were carried out using the Met Office Unified Model(MetUM)to investigate downslope *** smoothing method seamlessly blends two terrain datasets to which uniform smoothing has been applied—one with a minimum of smoothing,the other smoothed more heavily to remove gradients that would cause model *** latter dataset dominates the blend where the steepest slopes exist,but this is localised and recedes outside these *** a result,increased detail is starkly apparent in depictions of flow simulated using the blend,compared to one using the default *** includes qualitative flow details that were absent in the latter,such as narrow shooting flows emerging from roughly 1-2 km wide leeside *** separation is more common due to steeper lee *** use of targeted smoothing also results in increased lee side temporal variability at a given point during the windstorm,including over flat ***-/high-pass filtering of the wind perturbation field reveals that relative spatial variability above 30 km in scale(reflecting the background flow)is similar whether or not targeting is *** this scale,when smoothing is targeted,relative flow variability decreases at the larger scales,and increases at lower *** seems linked to fast smaller scale flows disturbing more coherent flows(notably an along-valley current over Erhai Lake).Spatial variability of winds in the model is unsurprisingly weaker at key times than is observed across a local network sampling mesoscale variation,but results are compromised due to relatively few observation locations sampling the *** when targeted smoothing is applied doe

关键词： lee wave turbulence mountain Tibetan Plateau aviation flow separation Foehn complex terrain

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：