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Modelling fuel loads of understorey vegetation and forest floor components in pine stands in NW Spain

Forest Ecosystems 2022年第6期9卷 775-789页

作者： jose A.vega Stefano Arellano-Perez juan Gabriel Alvarez-Gonzalez Cristina Fernandez Enrique jimenez Pedro Cuinas jose María Fernandez-Alonso daniel j.vega-nieva Fernando Castedo-Dorado Cecilia Alonso-Rego Teresa Fontúrbel Ana Daría Ruiz-Gonzalez Centro de Investigacion Forestal de Lourizan PO Box 12736080PontevedraSpain Unidad de Gestion Ambiental y Forestal Sostenible(UXAFORES) Departamento de Ingeniería AgroforestalEscuela Politecnica Superior de IngenieríaUniversidad de Santiago de CompostelaCampus Universitario s/n27002LugoSpain Facultad de Ciencias Forestales Universidad Juarez del Estado de DurangoRío Papaloapan y Blvd.Durango s/nCol.Valle del Sur34120DurangoMexico Departamento de Ingeniería y Ciencias Agrarias Universidad de LeonCampus de Ponferrada24401PonferradaSpain

In this study,310 destructively sampled plots were used to develop two equation systems for the three main pine species in NW Spain(***;*** and ***):one for estimating loads of understorey fuel components by size and condition(live and dead)and another one for forest floor *** systems of equations were simultaneously fitted for estimating fuel loads using overstorey,understorey and forest floor variables as *** systems of equations included both the effect of pine species and the effect of understorey compositions dominated by ferns-brambles or by woody species,due to their obvious structural and physiological *** general,the goodness-of-fit statistics indicated that the estimates were reasonably robust and accurate for all of the fuel *** best results were obtained for total understorey vegetation,total forest floor and raw humus fuel loads,with more than 76%of the observed variability explained,whereas the poorest results were obtained for coarse fuel loads of understory vegetation with a 53%of observed variability *** reduce the overall costs associated with the field inventories necessary for operational use of the models,the additive systems were fitted again using only overstorey variables as potential *** relationships for fine(<6 mm)and total understorey vegetation and total forest floor fuel loads were obtained,indicating the complexity of the forest overstorey-understorey and overstorey-forest floor ***,these models explained around 52%of the observed ***,equations estimating the total understorey vegetation and the total forest floor fuel loads based only on canopy cover were *** models explained only 26%-32%of the observed variability;however,their main advantage is that although understorey vegetation in forested landscapes is largely invisible to remote sensing,canopy cover can be estimated with moderate accuracy,allowin

关键词： Area-based approach Additive equation systems Live and dead fine fuel Pinus pinaster Pinus radiata Pinus sylvestris

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Drought and Spatiotemporal Variability of Forest Fires Across Mexico

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Chinese Geographical Science 2018年第1期28卷 25-37页

作者： Pompa-García MARíN Camarero j.jULIO Rodríguez-Trejo DANTE ARTURO vega-nieva daniel jOSE Facultad de Ciencias Forestales Universidad Juarez del Estado de Durango Durango 34120 MExico Instituto Pirenaico de Ecologia IPE-CSIC 50059 Spain Divisian de Ciencias Forestales Universidad Autonoma Chapingo Chapingo 56230 MExico

Understanding the spatiotemporal links between drought and forest fire occurrence is crucial for improving decision-making in fire management under current and future climatic conditions. We quantified forest fire activity in Mexico using georeferenced fire records for the period of 2005–2015 and examined its spatial and temporal relationships with a multiscalar drought index, the Standardized Precipitation-Evapotranspiration Index(SPEI). A total of 47975 fire counts were recorded in the 11-year long study period, with the peak in fire frequency occurring in 2011. We identified four fire clusters, i.e., regions where there is a high density of fire records in Mexico using the Getis-Ord G spatial statistic. Then, we examined fire frequency data in the clustered regions and assessed how fire activity related to the SPEI for the entire study period and also for the year 2011. Associations between the SPEI and fire frequency varied across Mexico and fire-SPEI relationships also varied across the months of major fire occurrence and related SPEI temporal scales. In particular, in the two fire clusters located in northern Mexico(Chihuahua, northern Baja California), drier conditions over the previous 5 months triggered fire occurrence. In contrast, we did not observe a significant relationship between drought severity and fire frequency in the central Mexico cluster, which exhibited the highest fire frequency. We also found moderate fire-drought associations in the cluster situated in the tropical southern Chiapas where agriculture activities are the main causes of forest fire occurrence. These results are useful for improving our understanding of the spatiotemporal patterns of fire occurrence as related to drought severity in megadiverse countries hosting many forest types as Mexico.

关键词： cluster drought forest fires geostatistics spatial clusters Standardised Precipitation-Evapotranspiration Index (SPEI)

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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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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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Financial instrument pricing using C++ / daniel j Duffy.

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2005年

作者： Duffy daniel j.

来源：畅想之星图书光盘版（南... 评论

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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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