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Growth Stratification Applied to prognosis of Diametric Structure in Araucaria Forest

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Journal of Applied Mathematics and physics 2014年第8期2卷 753-761页

作者： sylvio péllico netto Angelo Augusto Ebling Emanuel José Gomes de Araújo Department of Forest Science University Federal of Paraná Curitiba Brazil

The forest management, in broad terms, covers a set of information and activities related to the growth and production of plantations or from heterogeneous forests. If on one hand forest plantation presents homogeneous dendrometric characteristics, on the other hand in heterogeneous forests such a configuration does not exist, which requires the application of essential mathematical estimates for the forest management planning, for example, the prognosis of diametric structure. In this respect, refinements can be tested in traditionally used mathematical models, aiming at more accurate results. These facts substantiate the following hypotheses: the stratification of the diameter increments can provide estimates with greater accuracy and more precise results for the prognosis. With the stratification of diameter increment made it possible to get better results for the prognosis for a 4-year period, allowing the forest manager to better work with estimators either for diameter classes as well as for the forest to be managed. Using the data structure of trees (DBH ≥ 9.5 cm) of the National Forest of Sao Francisco de paula, RS, Brazil, the diameter increment of species was stratified into four statistically different strata. Using data sampled between the years of 2000 to 2004, it was carried out prognosis for the year 2008, using the stratified and not stratified data. The estimates were compared with the observed values by the Kolmogorov-Smirnov (K-S) test, which attested goodness of fit only for the estimates from the stratified values. The prognosis estimated by means of stratified values also showed more accurate results, because the stratified variance was reduced nine times when compared with that obtained with the prognosis made without stratified data and to determine the Quotient of De Liocourt. Thus, the diameter growth stratification indicated to be effective to generate more accurate prognosis.

关键词： Diameter projection Forest Management Heterogeneous Forest

Modifications on the Strand’s Sampling Method Applied to Stands of pinus elliottii Engelm

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Journal of Applied Mathematics and physics 2014年第7期2卷 593-602页

作者： sylvio péllico netto Doádi Antonio Brena Angelo Augusto Ebling Aurélio Lourenço Rodrigues Department of Forest Science University Federal of ParanáCuritibaBrazil Brazilian Forest Service BrasiliaBrazil

This work was carried out with the objective of proposing some changes in the Strand’s sampling method, in which the trees are selected in sampling units with probability proportional to its diameter for the calculation of the stand density and basal area, and proportional to its height for the calculation of volume per hectare. Data used to evaluate the efficiency of the sampling of Strand in clusters were collected in stands of pinus elliottii Engelm, located in a National Forest, Rio Grande do Sul State, Brazil. In the course of this research work it was proposed to convert the sampling unit into a cluster, structurally more efficient to obtain consistent estimates of volume and of dominant heights, using volumetric equivalence, which results in a form factor equal to one for the final calculation of volume per hectare and an indirect method to obtain the average height of Lorey. The objectives of this study were achieved, because with this methodology it is not necessary to measure heights of trees in the sampling unit, except a dominant height by cluster to evaluate sites. The development of independent estimators for basal area and volume gave rise to the proposition of an estimator for average height of Lorey, but without measuring any tree height in the sampling. The proposed methodology is an attractive solution to reduce costs in forest inventories, with the ability to have greater accuracy and scope for information at the level of compartments, without increasing the cost of sampling in comparison to that performed with units of fixed area. The use of smaller permanent sampling units with higher intensity in the compartments before the final cut will substantially increase the precision of the estimators in these management units, which will enable them to eliminate the pre-cut inventory in forest enterprises.

关键词： Cluster Sampling ppS Sampling Forest Inventory

probabilistic Distributions for <i>Acacia Mearnsii</i>De Wild Total Height and the Influence of Environmental Factors

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Journal of Applied Mathematics and physics 2014年第3期2卷 1-10页

作者： Carlos Roberto Sanquetta Alexandre Behling Allan Libano pelissari Ana paula Dalla Corte sylvio péllico netto Augusto Arlindo Simon Department of Forest Science University Federal of Paraná Curitiba Brazil

This paper discusses the hypothesis of height distribution on a forest stand of Acacia mearnsii De Wild, known as black wattle. It remains constant at varied growing environments and, in addition, they are not influenced by age factor. The Wakeby equation was applied. The research was carried out in a black wattle stand at varied age levels and over two different agroecological regions where plantations are found: Serra do Sudeste and Encosta do Sudeste, Rio Grande do Sul State, Brazil. It was observed that as the age rises there is an increase in the stand total height;while the number of trees decreases for the lower classes, it increases for the upper ones. This resulted in lengthening of the curve tail to the left and mode shift to the right, generating negative asymmetrical curves. Two types of height distribution were found: the sharp increase of probability in a specific class and some similar probabilities in successive classes. The distribution curves between the cultivation areas were statistically different and therefore the height distribution was dependent of environment.

关键词： Wakeby Distribution Forest Stand Age Cultivation Area Forest Structure

Unveiling the correlation between structural alterations and enhanced high-voltage cyclability in Na-deficient p3-type layered cathode materials via Li incorporation

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Electron 2024年第1期2卷 164-176页

作者： Xiaoxia Yang Suning Wang Hang Li Jochi Tseng Zhonghua Wu sylvio Indris Helmut Ehrenberg Xiaodong Guo Weibo Hua School of Chemical Engineering and Technology Xi'an Jiaotong UniversityXi'anChina School of Chemical Engineering Sichuan UniversityChengduChina Institute for Applied Materials(IAM) Karlsruhe Institute of Technology(KIT)Eggenstein‐LeopoldshafenGermany Diffraction and Scattering Division Japan Synchrotron Radiation Research Institute(JASRI)KoutoSayo‐choSayo‐gunHyogoJapan Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijingChina

With exceptional capacity during high-voltage cycling,p3-type Nadeficient layered oxide cathodes have captured substantial ***,they are plagued by severe capacity degradation over *** this study,tuning and optimizing the phase composition in layered oxides through Li incorporation are proposed to enhance the high-voltage *** structural dependence of layered Na_(2/3)LixNi_(0.25)Mn_(0.75)O_(2)þδoxides on the lithium content(0.0≤x≤1.0)offered during synthesis is investigated systematically on an atomic ***,increasing the Li content triggers the formation of mixed p2/O3-type or p3/p2/O3-type layered *** the voltage window is 1.5-4.5 V,p3-type Na2/3Ni_(0.25)Mn_(0.75)O_(2)(NL0.0NMO,R3m)material exhibits a sequence of phase transformations throughout the process of(de)sodiation,that is,O3⇌p3⇌O30⇌O3″.Such complicated phase transitions can be effectively suppressed in the Na2/3Li_(0.7)Ni_(0.25)Mn_(0.75)O_(2.4)(NL_(0.7)NMO)oxide with p2/p3/O3-type mixed ***,cathodes made of NL0.7NMO exhibit a substantially enhanced cyclic performance at high voltages compared to that of the p3-type layered NL0.0NMO ***,NL0.7NMO demonstrates an outstanding capacity retention of 98%after 10 cycles at 1 C within 1.5-4.5 V,much higher than that of NL0.0NMO(83%).This work delves into the intricate realm of bolstering the high-voltage durability of layered oxide cathodes,paving the way for advanced sodium-ion battery technologies.

关键词： high-voltage cycling Li incorporation phase transition sodium ion batteries triphasic composites

population structure of Araucaria angustifolia under distinct forest protection status:implications for management and conservation

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林业研究:英文版 2023年第5期34卷 1437-1446页

作者： Vinicius Costa Cysneiros Allan Libanio pelissari sylvio pellico netto Sebastiao do Amaral Machado Afonso Figueiredo Filho Departamento de Agricultura Biodiversidade e FlorestasUniversidade Federal de Santa Catarina-UFSCRodovia Ulysses GaboardiKm 03CuritibanosSC 89520-000Brazil Departamento de Ciencias Florestais Universidade Federal do Paraná-UFPRAv.Prof.Lothario Meissner632CuritibaPR 80210-170Brazil Departamento de Engenharia Florestal Universidade Estadual do Centro-Oeste-UNICENTROPR-153Km 7IratiPR 84500-000Brazil

Araucaria angustifolia is the dominant coniferous species in Brazil,a long-lived pioneer species and a supplier of valuable timber and non-timber products,which gives it key-species *** study examines how *** population structure affects the stand structure,and whether these relationships differ between protected and unprotected *** study was carried out on two protection status forests(national forest and urban forest)in a region of Atlantic mixed forest in paranáState,southern *** coefficient and the Weibull shape parameter described the population structure and its effects on species diversity and biomass *** diameter distribution differed significantly between forests,with unbalanced structure in both,although regeneration was more abundant in the protected *** positively affected aboveground biomass whereas shape negatively affected it and species *** relationships differed between protected and unprotected *** effect of *** populations on stand structure was conditioned on protection ***-growth populations may have lower diversity and biomass stock even supporting large ***,old-growth forests,can lead to wood loss through mortality,senescence,and declining populations,representing the waste of a valuable timber *** findings provide useful knowledge for forest management,species conservation,and the carbon market.

关键词： Key species Diameter distribution Weibull shape parameter Aboveground biomass

predicting the dynamics of a native Araucaria forest using a distance- independent individual tree-growth model

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Forest Ecosystems 2016年第3期3卷 231-241页

作者： Enrique Orellana Afonso Figueiredo Filho sylvio pellico netto Jerome Klaas Vanclay Midwest State University-UNICENTRO-pR PR 153 Km 7 Riozinho IratiParana 84500-000 Brazil Federal University of parana UFpR. Av. pref. Lothario Meissner 900 Jardim Botanico Curitiba Parana 80210-170 Brazil Southern Cross University (SCU) PO Box 157 Lismore NSW Australia

Background： In recent decades, native Araucaria forests in Brazil have become fragmented due to the conversion of forest to agricultural lands and commercial tree plantations. Consequently, the forest dynamics in this forest type have been poorly investigated, as most fragments are poorly structured in terms of tree size and diversity. Methods; We developed a distance-independent individual tree-growth model to simulate the forest dynamics in a native Araucaria forest located predominantly in southern Brazil. The data were derived from 25 contiguous plots （1 ha） established in a protected area left undisturbed for the past 70 years. The plots were measured at 3-year intervals from their establishment in 2002. All trees above a l O-cm diameter at breast height were tagged, identified as to species, and measured. Because this forest type comprises hundreds of tree species, we clustered them into six ecological groups： understory, subcanopy, upper canopy shade-tolerant, upper canopy light-demanding, pioneer, and emergent. The diameter increment, survival, and recruitment sub-models were fitted for each species group, and parameters were implemented in a simulation software to project the forest dynamics. The growth model was validated using independent data collected from another research area of the same forest type. To simulate the forest dynamics, we projected the species group and stand basal areas for 50 years under three different stand-density conditions： low, average, and high. Results： Emergent species tended to grow in basal area, irrespective of the forest density conditions. Conversely, shade-tolerant species tended to decline over the years. Under low-density conditions, the model showed a growth tendency for the stand basal area, while under average-density conditions, forest growth tended to stabilize within 30 years. Under high-density conditions, the model indicated a decline in the stand basal area from the onset of the simulation, suggesting that und

关键词： Forest succession Species group Araucafia angustifolia

Elucidation of the sodiation/desodiation mechanism in Ca_(0.5)Ti_(2)(pO_(4))_(3)/C as promising electrode for sodium batteries: New insights into the phase transitions

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Journal of Energy Chemistry 2022年第7期31卷 36-44,I0002页

作者： Abdelhaq Nassiri Noha Sabi Angelina Sarapulova Yingjin Wei Bouchaib Manoun sylvio Indris Alexandr Missyul Helmut Ehrenberg Ismael Saadoune IMED-Lab Faculty of Science and Technology-Cadi Ayyad University(UCA)Av.A.El KhattabiP.B.549MarrakeshMorocco Institute for Applied Materials(IAM) Karlsruhe Institute of Technology(KIT)P.O.Box 364076021 KarlsruheGermany Key Laboratory of physics and Technology for Advanced Batteries(Ministry of Education) Jilin Engineering Laboratory of New Energy Materials and TechnologyCollege of PhysicsJilin UniversityChangchun 130012JilinChina MSN Mohamed VI Polytechnic UniversityLot 660Hay Moulay RachidBen Guerir 43150Morocco CELLS-ALBA Synchrotron E-08290 Cerdanyola del VallesBarcelonaSpain Technology Development Cell(Techcell) Technology Transfer Office(TTO)Mohamed VI Polytechnic UniversityLot 660Hay Moulay RachidBen Guerir 43150Morocco

The structure evolution and electrochemical performance of Na SICON-type Ca_(0.5)Ti_(2)(pO_(4))_(3) for sodium batteries are *** phosphate was synthesized by a solid-state method,and the obtained particles were coated with carbon using *** compound crystallizes in the rhombohedral system with space group *** presence of carbon in the Ca_(0.5)Ti_(2)(pO_(4))_(3)/C composite was confirmed by Raman and Thermogravimetric *** electrochemical performance of Ca_(0.5)Ti_(2)(pO_(4))_(3)/C was investigated in the potential window 1.5–3.0 V *** metal at different scan *** compound is able to initially intercalate/deintercalate 1.6/1.15 Na per formula unit,*** operando synchrotron diffraction was done in the potential window 0.02–3.0 V ***|Na+and revealed the occurrence of several reaction regions upon first *** to 4 Na+ion per formula unit can be inserted during the first *** intensive refinement of the synchrotron X-ray diffraction(SXRD)patterns of discharged Ca_(0.5)Ti_(2)(pO_(4))_(3) evidenced the existence of five regions depending on the sodium content while the crystal structures of new phases were elucidated for the first time where sodium insertion occurs in the unusual M3 and M’3 sites of the Na SICON structure.

关键词： Sodium-ion batteries phosphates Synchrotron Mechanism Energy storage

Tracking leaf area index and coefficient of light extinction over the harvesting cycle of black wattle

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Journal of Forestry Research 2016年第6期27卷 1211-1217页

作者： Aiexandre Behling Carlos Roberto Sanquetta Ana paula Dalla Corte sylvio pellico netto Aurelio Lourenco Rodrigues Braulio Otomar Caron Augusto Arlindo Simon Federal University of parana 900Lothario Meissner AvCuritibaParana 80210-170Brazil Federal University of Santa Maria 1000 Roraima AvSanta MariaRio Grande do SulBrazil TANAC SA 199 Torbjom Weibull StMontenegroRio Grande do SulBrazil

The amount of photosynthetic radiation inter- cepted by a crop is a function of the incident solar radiation on the plants, the leaf area index （LAI）, and the light extinction coefficient （k）. We quantified LAI and k in stands of black wattle （Acacia mearnsii De Wild.） over a 7-year growth cycle at two locations in the state of Rio Grande do Sul, Brazil. Our study was conducted in commercial stands in agroecological regions with high densities of black wattle plantations. LAI was calculated as the ratio between the leaf area of a tree and its planting space, and k was derived from Beer＇s law. LAI depends on the planting site and stand age. Between the two sites, the LAI was similar over time, the amount of variation differed. Values of k depended only on stand age, with the highest average observed for stands up to 5 years old. The trend of k during the plantation cycle was inversely proportional to LAI and was correlated with LAI, leaf area, leaf dry mass, canopy volume, height, branches dry mass, total dry mass, and crown diameter.

关键词： Leaf area - Light attenuation Tree canopy Biomass photosynthetic radiation intercepted

Measurement of the flow structures in the wakes of different types of parachute canopies

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Acta Mechanica Sinica 2018年第2期34卷 225-237页

作者： sylvio pasqualini Zheyan Jin Zhigang Yang School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai 200092China Shanghai Key Lab of Vehicle Aerodynamics and Vehicle Thermal Management Systems Shanghai 201804China

We measured flow structures with stereoscopic particle image velocimetry(stereo-pIV) in the turbulent wakes of three parachute canopies, which had the same surface area, but different geometries. The tested parachute canopies included ribbon canopy, 8-branches canopy, and cross canopy. The obtained results showed that the geometry of the parachute canopies had significant influences on the flow structures in the wakes of these three canopies. In addition, the variation of Reynolds number did not lead to a dramatic change in the distributions of velocity, vorticity,Reynolds stress, and turbulent kinetic energy.

关键词： parachute canopies Wake structures particle image velocimetry