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Estimating Pinus palustris tree diameter and stem volume from tree height,crown area and stand-level parameters

journal of Forestry Research 2014年第1期25卷 43-52页

作者： C.A.Gonzalez-Benecke Salvador A.Gezan Lisa j.Samuelson Wendell P.Cropper daniel j.leduc Timothy A.Martin School of Forest Resources and Conservation P.O.Box 110410University of Florida School of Forestry and Wildlife Sciences 3301SFWS BuildingAuburn University USDA Forest Service Southern Research StationAlexandria Forestry Center

Accurate and efficient estimation of forest growth and live biomass is a critical element in assessing potential responses to forest management and environmental change. The objective of this study was to develop models to predict longleaf pine tree diameter at breast height （dbh） and merchantable stem volume （V） using data obtained from field measurements. We used longleaf pine tree data from 3,376 planted trees on 127 permanent plots located in the U.S. Gulf Coastal Plain region to fit equations to predict dbh and V as functions of tree height （H） and crown area （CA）. Prediction of dbh as a function of H improved when CA was added as an additional independent variable. Similarly, predic- tions of V based on H improved when CA was included. Incorporation of additional stand variables such as age, site index, dominant height, and stand density were also evaluated but resulted in only small improvements in model performance. For model testing we used data from planted and naturally-regenerated trees located inside and outside the geographic area used for model fitting. Our results suggest that the models are a robust alternative for dbh and V estimations when H and CA are known on planted stands with potential for naturally-regenerated stands, across a wide range of ages. We discuss the importance of these models for use with metrics derived from remote sensing data.

关键词： Longleaf pine diameter-height relationships crown area individual-tree stem volume growth and yield modeling

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Ecosystem management in paludified boreal forests:enhancing wood production,biodiversity,and carbon sequestration at the landscape level

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Forest Ecosystems 2018年第4期5卷 376-389页

作者： Benoit Lafleur Nicole j.Fenton Martin Simard Alain leduc David Paré Osvaldo Valeria Yves Bergeron NSERC-UQAT-UQAM Industrial Chair in Sustainable Forest Management and Institut de recherche sur les forêts Université du Québec en Abitibi-Témiscamingue445boul.de I'UniversiteRouyn-NorandaQC J9X 5E4Canada Department of Geography Laval UniversityQuebecQC GIV 0A6Canada Centre d'etude de la foret Universite du Quebec a Montreal141 Avenue du President-KennedyMontrealQC H2X IY4Canada Ressources Naturelles Canada Service canadien des forets Centre de foresterie des Laurentides1055du P.E P S.P.O.13ox 3800QuebecQC GIV 4C7Canada

Canada’s boreal forest represents an important contributor of the world’s wood supply industry. However,maintaining or increasing productivity of the boreal forest may be challenging in areas dominated by forested peatlands. Moreover, sustainable management of these forests must also consider other important aspects of the forest ecosystem such as biodiversity and carbon sequestration. To address these concerns, ecosystem-based management has been implemented in some Canadian jurisdictions, such as in regions where a large portion of the boreal forest is dominated by forested peatlands. The objectives of this paper are(1) to summarize our current understanding of how natural disturbances influence stand dynamics and biodiversity in forested peatlands, and(2) to review the main differences between natural and managed forest stands with respect to soil properties, stand productivity, understory plant communities. We also discuss how even-age management regime succeeds or fails to preserve old forests and how this loss affects both forest structure and habitat diversity at the landscape *** conclude by showing how, in boreal forested peatlands, forest management could contribute to carbon sequestration and mitigate projected climate change.

关键词： Clearcutting Fire Forest dynamics Partial cutting Soil properties Stand productivity Understory plant

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Laser cut hole matrices in novel armour plate steel for appliqué battlefield vehicle protection

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Defence Technology（防务技术） 2016年第5期12卷 351-359页

作者： daniel j. THOMAS Engineering Manufacturing Centre College of Engineering Swansea University Swansea UK

During this research, experimental rolled homogeneous armour steel was cast, annealed and laser cut to form an appliqué plate. This Martensitic–Bainitic microstructure steel grade was used to test a novel means of engineering lightweight armour. It was determined that a laser cutting speed of 1200 mm/min produced optimum hole formations with limited distortion. The array of holes acts as a double-edged solution, in that they provide weight saving of 45%, providing a protective advantage and increasing the surface area. Data collected were used to generate laser cut-edge hole projections in order to identify the optimum cutting speed, edge condition, cost and deformation performance. These parameters resulted in the generation of a surface, with less stress raising features. This can result in a distribution of stress across the wider surface. Provided that appropriate process parameters are used to generate laser cut edges, then the hardness properties of the surface can be controlled. This is due to compressive residual stresses produced in the near edge region as a result of metallurgical transformations. This way the traverse cutting speed parameter can be adjusted to alter critical surface characteristics and microstructural properties in close proximity to the cut-edge. A relationship was identified between the width of the laser HAZ and the hardness of the cut edge. It is the thickness of the HAZ that is affected by the laser process parameters which can be manipulated with adjusting the traverse cutting speed.

关键词： Armour steels Defence systems Steel processing Armour engineering

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A high-order SPH method by introducing inverse kernels

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Chinese journal of Aeronautics 2017年第1期30卷 1-14页

作者： Fang Le Marongiu jean Christophe leduc julien Amicarelli Andrea Caro joёlleb LMP Ecole centrale de Pekin Beihang University Co-Innovation Center for Advanced Aero-Engine 100083 Beijing China LMFA Ecole centrale de Lyon 69130 Ecully BP 163 France Laboratoire International Associe Beihang University 100083 Beijing China ANDRITZ HYDRO AG Rue des Deux-Gares 6 1800 Vevey Switzerland

The smoothed particle hydrodynamics（SPH） method is usually expected to be an efficient numerical tool for calculating the fluid-structure interactions in compressors; however, an endogenetic restriction is the problem of low-order consistency. A high-order SPH method by introducing inverse kernels, which is quite easy to be implemented but efficient, is proposed for solving this restriction. The basic inverse method and the special treatment near boundary are introduced with also the discussion of the combination of the Least-Square（LS） and Moving-Least-Square（MLS） methods. Then detailed analysis in spectral space is presented for people to better understand this method. Finally we show three test examples to verify the method behavior.

关键词： Consistency High-order method Inverse method Numerical dissipation Numerical instability Smoothed particle hydrodynamics

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The PACTUM model:Product analysis of cost and time using mathematics

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International journal of Modeling, Simulation, and Scientific Computing 2014年第S01期5卷 51-70页

作者： daniel j.Easters Department of Fashion Marketing Management&Communication School of Art&Design Nottingham Trent University Nottingham NG14BUUK

Establishing a mathematical supply-chain model is a proposition that has received attention due to its inherent benefits of evolving global supply-chain *** paper discusses the prevailing relationships found within apparel supply-chain environments,and contemplates the complex issues indicated for constituting a mathematical *** results identified within the data suggest,that the multifarious nature of global supply-chain activities require a degree of simplification in order to fully dilate the necessary factors which affect,each subsection of the ***,the research findings allowed the division of supply-chain components into subsections,which amassed a coherent method of product development ***,the supply-chain model was found to allow systematic mathematical formulae analysis,of cost and time,within the multiple contexts of each subsection *** paper indicates the supplychain model structure,the mathematics,and considers how product analysis of cost and time can improve the comprehension of product lifecycle management.

关键词： Fashion supply-chain mathematics

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Recent advances in the targeted fluorescent probes for the detection of metastatic bone cancer

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Science China Chemistry 2021年第8期64卷 1283-1296页

作者： Peng Wu daniel j.Siegwart Hu Xiong Research Center for Analytical Sciences Tianjin Key Laboratory of Biosensing and Molecular RecognitionCollege of ChemistryNankai UniversityTianjin300071China Department of Biochemistry Simmons Comprehensive Cancer CenterThe University of Texas Southwestern Medical CenterDallasTexas75390USA

Tumors of the breast,prostate,and lung are most likely to metastasize to the bone and typically indicates a poor cure and survival rate in cancer *** of metastatic bone cancer in early stage would save many lives and greatly improve patients’quality of ***,bone scintigraphy is often utilized to visualize bone metastases due to its relatively low cost and high ***,a growth number of analytical researches aimed at developing targeted fluorescent probes to noninvasively image bone metastases with improved spatial resolution and specificity has been *** this review,we will summarize and discuss the recent published fluorescent probes on the accurate detection of metastatic bone ***,the design principles of various targeted probes for imaging bone metastases will be presented,highlighting the signal moieties,targeting ligands,and physicochemical properties of the bone-specific ***,the up-to-date bone-targeting fluorescent probes will be summarized and ***,future perspectives and challenges confronting the researchers in this field will be *** believe this review will encourage novel ideas to develop smart targeted molecular probes for bone metastasis imaging,image-guided surgery,and therapeutic imaging materials.

关键词： bone metastasis targeted probes fluorescence imaging smart design bone-targeting moieties

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Overcoming obstacles to implementation: addressing political,institutional and behavioral problems in earthquake hazard mitigation policies

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Earthquake Engineering and Engineering Vibration 2002年第1期1卷 152-158页

作者： daniel j.Alesch William j.Petak Department of Public and Environmental Affairs University of Wisconsin-Green BayGreen BayWisconsin54311USA Professor School of Policy Planning and DevelopmentUniversity of Southern California650 Childs WayRoom 201eLos AngelesCalifornia90089-0626USA Professor

This project is aimed at bridging the three planes,from basic research,through enabling processes,to engineered *** the basic research plane,we have been working to improve our collective understanding about obstacles to implementing mitigation practices,owner decision processes (in connection with other MCEER projects),and public policy *** the level of enabling processes,we have been seeking to develop an understanding of how obstacles to greater mitigation can be overcome by improved policy design and *** the engineered systems plane, our work is intended to result in practical guidelines for devising policies and programs with appropriate motivation and incentives for implementing policies and programs once *** phase of the research has been aimed,first,at a thorough,multidisciplinary review of the literature concerning obstacles to ***,the research has focused on advancing the state of the art by developing means for integrating the insights offered by diverse perspectives on the implementation process from the several social,behavioral,and decision *** research establishes a basis for testing our understanding of these processes in the case of hospital retrofit decisions.

关键词： earthquake mitigation earthquake mitigation policies earthquake losses

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Design of synthetic materials for intracellular delivery of RNAs： From siRNA-mediated gene silencing to CRISPR/Cas gene editing

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Nano Research 2018年第10期11卷 5310-5337页

作者： jason B. Miller daniel j. Siegwart Simmons Comprehensive Cancer Center University of Texas Southwestern Medical Center Dallas TX 75390 USA Department of Biochemistry University of Texas Southwestern Medical Center Dallas TX 75390 USA

Ribonucleic acids （RNAs） possess great therapeutic potential and can be used to treat a variety of diseases. The unique biophysical properties of RNAs, such as high molecular weight, negative charge, hydrophilicity, low stability, and potential immunogenicity, require chemical modification and development of carriers to enable intracellular delivery of RNAs for clinical use. A variety of nanornaterials have been developed for the effective in vivo delivery of short/ small RNAs, messenger RNAs, and RNAs required for gene editing technologies including clustered regularly interspaced palindromic repeat （CRISPR）/Cas. This review outlines the challenges of delivering RNA therapeutics, explores the chemical synthesis of RNA modifications and carriers, and describes the efforts to design nanomaterials that can be used for a variety of clinical indications.

关键词： nucleic acid therapeutics nanoparticles synthetic nanomaterials RNA interference (RNAi) messenger RNA (mRNA) clustered regularly inter-spaced palindromic repeat(CRISPR)/Cas

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Current applications of artificial intelligence for intraoperative decision support in surgery Allison

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Frontiers of Medicine 2020年第4期14卷 369-381页

作者： j.Navarrete-Welton daniel A.Hashimoto Surgical Artificial Intelligence and Innovation Laboratory Massachusetts General HospitalBostonMA 02114USA Harvard Medical School BostonMA 02114USA

Research into medical artificial intelligence(AI)has made significant advances in recent years,including surgical *** scoping review investigated AI-based decision support systems targeted at the intraoperative phase of surgery and found a wide range of technological approaches applied across several surgical *** the twenty-one(n=21)included papers,three main categories of motivations were identified for developing such technologies:(1)augmenting the information available to surgeons,(2)accelerating intraoperative pathology,and(3)recommending surgical *** many of the proposals hold promise for improving patient outcomes,important methodological shortcomings were observed in most of the reviewed papers that made it difficult to assess the clinical significance of the reported performance *** limitations,the current state of this field suggests that a number of opportunities exist for future researchers and clinicians to work on AI for surgical decision support with exciting implications for improving surgical care.

关键词： artificial intelligence decision support clinical decision support systems intraoperative deep learning computer vision machine learning surgery

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Periodic Orbits in Rotating Second Degree and Order Gravity Fields

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Chinese journal of Astronomy and Astrophysics 2008年第1期8卷 108-118页

作者： Wei-Duo Hu daniel j. Scheeres School of Astronautics BeiHang University Beijing 100083 Department of Aerospace Engineering The University of Michigan Ann Arbor MI48109 USA

Periodic orbits in an arbitrary 2nd degree and order uniformly rotating gravity field are studied. We investigate the four equilibrium points in this gravity field. We see that close relation exists between the stability of these equilibria and the existence and stability of their nearby periodic orbits. We check the periodic orbits with non-zero periods. In our searching procedure for these periodic orbits, we remove the two unity eigenvalues from the state transition matrix to find a robust, non-singular linear map to solve for the periodic orbits. The algorithm converges well, especially for stable periodic orbits. Using the searching procedure, which is relatively automatic, we find five basic families of periodic orbits in the rotating second degree and order gravity field for planar motion, and discuss their existence and stability at different central body rotation rates.

关键词： celestial / orbital mechanics - asteroid - periodic orbit - resonance

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