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Increasing Biomass Production on Limited Land Area Through an Optimal Planting Arrangement

BIOENERGY RESEARCH 2018年第1期11卷 13-21页

作者： Oswald, Scott W. Aubrey, Doug P. Univ Georgia Warnell Sch Forestry & Nat Resources Athens GA 30602 USA Univ Georgia Savannah River Ecol Lab Aiken SC 29802 USA

Planting density is a primary consideration in silviculture;however, planting arrangement is often ignored. Most, if not all, forest plantations are arranged in rectangular or square lattices (i.e., grids). Using a simple mathematical model, we investigate the potential influence of planting arrangement on planting density, biomass yield, and rotation period by assuming that efficiently arranging trees is similar to packing congruent circles on a plane. The hexagonal lattice achieves the densest circle packing on a plane;therefore, a hexagonal or triangular lattice arrangement of stems provides the highest planting density for a given spacing. Using packing density to quantify arrangement efficiency, tree crowns in a hexagonal lattice fill approximately 90.7% of available area at initial canopy contact, while tree crowns in a square lattice fill approximately 78.5% of available area at initial canopy contact. The hexagonal lattice permits about a 15% higher density than the square lattice, which allows canopy closure to occur earlier without any change in individual tree growth. Short rotation woody crop (SRWC) systems are excellent candidates under the model's assumptions of level stand with even-age monoculture. If belowground resources are non-limiting, a hexagonal lattice arrangement shortens rotation period and thus optimizes the biomass yield per land area over time. Higher productivity over time is central to sustainable and efficient use of limited area for bioenergy and biomass products.

关键词： Forest productivity Planting density Tree spacing Bioenergy production Hexagonal lattice Triangular lattice Biomass yield rectangularity Short rotation woody crops

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Identification of Linear Vegetation Elements in a Rural Landscape Using LiDAR Point Clouds

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REMOTE SENSING 2019年第3期11卷 292-292页

作者： Lucas, Chris Bouten, Willem Koma, Zsofia Kissling, W. Daniel Seijmonsbergen, Arie C. Geodan President Kennedylaan 1 NL-1079 MB Amsterdam Netherlands Vrije Univ Amsterdam Spatial Informat Lab SPINLab De Boelelaan 1105 NL-1081 HV Amsterdam Netherlands Univ Amsterdam Inst Biodivers & Ecosyst Dynam POB 94248 NL-1090 GE Amsterdam Netherlands

Modernization of agricultural land use across Europe is responsible for a substantial decline of linear vegetation elements such as tree lines, hedgerows, riparian vegetation, and green lanes. These linear objects have an important function for biodiversity, e.g., as ecological corridors and local habitats for many animal and plant species. Knowledge on their spatial distribution is therefore essential to support conservation strategies and regional planning in rural landscapes but detailed inventories of such linear objects are often lacking. Here, we propose a method to detect linear vegetation elements in agricultural landscapes using classification and segmentation of high-resolution Light Detection and Ranging (LiDAR) point data. To quantify the 3D structure of vegetation, we applied point cloud analysis to identify point-based and neighborhood-based features. As a preprocessing step, we removed planar surfaces such as grassland, bare soil, and water bodies from the point cloud using a feature that describes to what extent the points are scattered in the local neighborhood. We then applied a random forest classifier to separate the remaining points into vegetation and other. Subsequently, a rectangularity-based region growing algorithm allowed to segment the vegetation points into 2D rectangular objects, which were then classified into linear objects based on their elongatedness. We evaluated the accuracy of the linear objects against a manually delineated validation set. The results showed high user's (0.80), producer's (0.85), and total accuracies (0.90). These findings are a promising step towards testing our method in other regions and for upscaling it to broad spatial extents. This would allow producing detailed inventories of linear vegetation elements at regional and continental scales in support of biodiversity conservation and regional planning in agricultural and other rural landscapes.

关键词： rural landscapes classification LiDAR linear vegetation object recognition point cloud rectangularity segmentation

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Morphometry of the diatom Fragilariopsis kerguelensis from Southern Ocean sediment: High-throughput measurements show second morphotype occurring during glacials

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MARINE MICROPALEONTOLOGY 2018年 143卷 70-79页

作者： Kloster, Michael Kauer, Gerhard Esper, Oliver Fuchs, Nike Beszteri, Bank Helmholtz Zentrum Polar & Meeresforsch Alfred Wegener Inst Handelshafen 12 D-27570 Bremerhaven Germany Hsch Emden Leer Constantiapl 4 D-26723 Emden Germany

Fragilariopsis kerguelensis is one of the most abundant diatoms in the sediments of the Southern Ocean. Its morphometric features have been proposed as proxies, based on links with, for example, iron availability, sea surface temperature and glacial/interglacial conditions. We investigated morphometric changes in F. kerguelensis valves in a well-studied sediment core record, focusing on transition periods between glacials and interglacials. By applying a high-throughput diatom imaging and morphometry workflow, we found two clearly distinct morphotypes which were differentiated by their rectangularity. One of them occurred preferentially in glacial samples, whilst the other persisted throughout. This indicates that their relative abundances depend on environmental conditions and thereby points to the possibility that paleo-proxies based on F. kerguelensis valve morphometric features might in the future benefit from differentiating these two morphotypes. As an initial exploration of this idea, we show that the abundance ratio of both morphotypes correlates well with paleotemperatures which had been reconstructed using independent data from the same core. Distinguishing between the two morphotypes only became possible by image analysis for precisely measuring diatom valve outlines and area, highlighting the potential of such methods for diatom analyses.

关键词： Paleoceanography SHERPA Proxy Valve area rectangularity Holocene

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Recursive maxmin preferences and rectangular priors: a simple proof

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ECONOMIC THEORY BULLETIN 2019年第1期7卷 125-129页

作者： Amarante, Massimiliano Siniscalchi, Marciano Univ Montreal Dept Sci Econ Montreal PQ H3C 3J7 Canada CIREQ Montreal PQ H3C 3J7 Canada Northwestern Univ Dept Econ Evanston IL 60208 USA

We provide a simple proof of a key element of the characterization of recursive maxmin preferences in Epstein and Schneider (J Econ Theory 113:1-31, 2003).

关键词： Recursive multiple priors Dynamic consistency rectangularity D80 D81

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Changing Times: Altering Establishment Spacing, Harvesting Frequency, and Harvesting Machines to Promote Increased Sawtimber Volumes

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FRONTIERS IN ENERGY RESEARCH 2018年第JUN期6卷

作者： Daniel, Marissa Jo Gallagher, Tom Mitchell, Dana McDonald, Timothy Via, Brian Auburn Univ Sch Forestry & Wildlife Sci Auburn AL 36849 USA US Forest Serv USDA Southern Res Stn Auburn AL USA Auburn Univ Biosyst Engn Auburn AL 36849 USA

Today's landowners are faced with important decisions when establishing loblolly pine plantations in the Southeastern part of the United States with regards to planting dimensions and forest management techniques. Although recent studies are beginning to demonstrate the need for change from the old practices, suppressed biomass markets and prices are hindering the transition. This paper provided readers with an informational overview of the benefits of: incorporating an additional thinning regime for biomass, using alternate spacing methods such as Flexstands (TM) and rectangularity, and using small-scale harvesting machines for conducting initial thinning's. The overview was supported with both a field study as well as a modeling tool which verified using one or all of the above mentioned techniques to increase total harvest volumes while minimizing residual stand damage. The modeling tool determined that final sawtimber volumes were increased by a minimum of 15 green tons per acre using one or more of the above techniques. When expanding this volume out to 20 acres, the minimum tract size harvested in the southeast using convention equipment, landowners could easily recover any losses incurred from the suppressed biomass markets minimizing overall risk and promoting the use of these alternative techniques.

关键词： flex plantations rectangularity small-scale harvesting woody biomass Ptaeda modeling

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Rectangular Sets of Probability Measures

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OPERATIONS RESEARCH 2016年第2期64卷 528-541页

作者： Shapiro, Alexander Georgia Inst Technol Sch Ind & Syst Engn Atlanta GA 30332 USA

In this paper we consider the notion of rectangularity of a set of probability measures from a somewhat different point of view. We define rectangularity as a property of dynamic decomposition of a distributionally robust stochastic optimization problem and show how it relates to the modern theory of coherent risk measures. Consequently, we discuss robust formulations of multistage stochastic optimization problems in frameworks of stochastic programming, stochastic optimal control, and Markov decision processes.

关键词： multistage stochastic optimization rectangularity risk-averse optimization robust optimal control and Markov decision processes dynamic programming coherent risk measures time consistency

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Dynamic consistency in incomplete information games under ambiguity

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INTERNATIONAL JOURNAL OF APPROXIMATE REASONING 2016年第0期76卷 63-79页

作者： Liu, Hailin Xiong, Wei Sun Yat Sen Univ Dept Philosophy Inst Log & Cognit Guangzhou Guangdong Peoples R China

We develop a general framework of incomplete information games under ambiguity which extends the traditional framework of Bayesian games to the context of Ellsberg-type ambiguity. We then propose new solution concepts called ex ante and interim Gamma-maximin equilibrium for solving such games. We show that, unlike the standard notion of Bayesian Nash equilibrium, these concepts may lead to rather different recommendations for the same game under ambiguity. This phenomenon is often referred to as dynamic inconsistency. Moreover, we characterize the sufficient condition under which dynamic consistency is assured in this generalized framework. (C) 2016 Elsevier Inc. All rights reserved.

关键词： Dynamic consistency Incomplete information games Ambiguity Gamma-maximin rectangularity

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SHAPE rectangularity MEASURES

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INTERNATIONAL JOURNAL OF PATTERN RECOGNITION AND ARTIFICIAL INTELLIGENCE 2012年第6期26卷 1254002-1254002页

作者： Zunic, Dragisa Martinez-Ortiz, Carlos Zunic, Jovisa Ecole Polytech Fed Lausanne IC LARA BC CH-1015 Lausanne Switzerland Fac Econ & Engn Management Novi Sad Serbia Univ Exeter Exeter EX4 4QF Devon England

This paper introduces a family of rectangularity measures. The measures depend on two parameters which enable their exibility, i.e. the possibility to adapt with respect to a concrete application. Several rectangularity measures exist in the literature, and they are designed to evaluate numerically how much the shape considered differs from a perfect rectangle. None of these measures distinguishes rectangles whose edge ratios differ, i.e. they assume that all rectangles (including squares) have the same shape. Such property can be a disadvantage in applications. In this paper, we consider differently elongated rectangles to have different shapes, and propose a family of new rectangularity measures which assigns different values to rectangles whose edge ratios direr. The new rectangularity measures are invariant with respect to translation, rotation and scaling transformations. They range over the interval ]0, 1] and attain the value 1 only for perfect rectangles with a desired edge ratio.

关键词： Shape rectangularity measuring shape image retrieval image processing

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Aerospace series - Connector, electrical and optical, rectangular, modular, rectangular inserts, operating temperature 175oC (or 125oC) continuous - Part 133 : size 3 receptacle for rack and panel application, class C and D - Product standard

Aerospace series - Connector, electrical and optical, rectan...

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标准类型：法国标准

La présente Norme européenne spécifie une embase de taille 3 pour application rackable utilisée dans la famille des connecteurs électriques et optiques, rectangulaires, modulaires, avec insert... 详细信息

标准号: NF L54-102-133-2016

关键词： Laps Bushings Marking Coded representation Coding (data conversion) Data representation Prevailing torque type rectangularity Bands Coding (programming) Electric connectors Bundles Designations Mass Air transport Dimensions Collars Properties Rectangular shape

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Specifications for particular types of winding wires - Part 0-4 : general requirements - Glass-fibre wound, resin or varnish impregnated, bare or enamelled rectangular copper wire

Specifications for particular types of winding wires - Part ...

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标准类型：法国标准

La présente partie de la IEC 60317 spécifie les exigences générales relatives au fil de section rectangulaire en cuivre nu ou émaillé guipé de fibres de verre imprégnées de... 详细信息

标准号: NF C31-317-0-4-2016

La présente partie de la IEC 60317 spécifie les exigences générales relatives au fil de section rectangulaire en cuivre nu ou émaillé guipé de fibres de verre imprégnées de vernis ou de résine.

关键词： Elongation Non-insulated wires Breakdown voltage Packaging Enamelled wires Treatment Tables (data) Specifications Textile-covered wires Purification Conditioning rectangularity Cold-bend behaviour Insulated wires Expansions Glass fibres Winding Adhesion Dimensions Glass filament Copper Extensions Rectangular shape Preparation

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