National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for submerged aquatic vegetation (SAV) in New Hampshire. Vector polygons in this data set represent habitat...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for estuarine turtles in New Hampshire. Vector polygons in this data set represent turtle distribution....
Sensitivity of Coastal Environments and Wildlife to Spilled Oil: New Hampshire: FISH (Fish Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, and anadromous fish species in New Hampshire. Vector polygons in this data set...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for seals, porpoise, and whales in New Hampshire. Vector polygons in this data set represent marine mammal...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for northern river otters, beavers, and muskrats in New Hampshire. Vector polygons in this data set...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains management area data for special management areas, nature preserves, state/regional parks, and wildlife refuges in New Hampshire. Vector...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries of all the hardcopy cartographic products produced as part of the Environmental Sensitivity Index...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for New...
An equal area conversion model for rasterization of vector polygons
ZHOU ChengHu; OU Yang; YANG Liao; QIN Biao
2007-01-01
Vector-raster conversion is one of the classic research topics in the field of Geographical Information Systems (GIS). The algorithms commonly used in GIS are devoted to maintaining the vector polygons' shape characteristics, but neglect the gain and loss of a polygon's area, which is another important attribute. This paper proposes an equal-area conversion model based on an area compensation optimization principle. According to the topological relationship among polygons and boundary grids, a neighborhood compensation principle was adopted to assign the attributes of boundary grids and a global optimization algorithm was developed to minimize area distortion in the whole data set. Two experiments were designed and the results indicated that this algorithm not only guaranteed the area error is as small as possible, but also has the advantage as being adaptive to polygon shape and spatial structure.
Riosa, Blažka
2014-01-01
In mathematics we often encounter polygons, such us triangle, square, hexagon, etc., but we hardly encounter star polygons. Despite the fact that we do not meet them so often in mathematics, in nature they can be traced almost on every step. In this paper the emphasis is on the geometric meaning of regular star polygons. Star polygon is a generalization of the concept of regular polygons. In star polygons also non-adjacent sides intersect. Up to similarity they are determined by Schläfli symb...
Virginia ESI: FISH (Fish Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and brackishwater fish species in Virginia. Vector polygons in this data...
Alabama ESI: HABITATS (Habitat Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for submerged aquatic vegetation (SAV) and rare plants in Alabama. Vector polygons in this data set...
Virginia ESI: INVERT (Invertebrate Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, and rare invertebrate species in Virginia. Vector polygons in this data set...
Virginia ESI: INDEX (Index Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries of all hardcopy cartographic products produced as part of the Environmental Sensitivity Index...
Virginia ESI: Wetlands (Wetland Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the coastal wetlands for Virginia, classified according to the Environmental Sensitivity Index (ESI)...
Maryland ESI: HABITATS (Habitat Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for submerged aquatic vegetation (SAV) and rare plants in Maryland. Vector polygons in this data set...
Hawaii ESI: FISH (Fish Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for reef, marine, estuarine, and native stream fish species in coastal Hawaii. Vector polygons in this data...
Virginia ESI: REPTILES (Reptile Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for sea turtles and estuarine turtles in Virginia. Vector polygons in this data set represent turtle...
Alabama ESI: FISH (Fish Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, and freshwater fish species in Alabama. Vector polygons in this data set represent...
Louisiana ESI: BIRDS (Bird Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for waterfowl species and shorebirds in coastal Louisiana. Vector polygons in this data set represent...
Louisiana ESI: INDEX (Index Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries of all the hardcopy cartographic products produced as part of the Environmental Sensitivity Index...
Hawaii ESI: INDEX (Index Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries of the U.S. Geological Survey 1:24,000 topographic maps and other map and digital data boundaries...
Alabama ESI: INVERT (Invertebrate Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine and estuarine invertebrate species in Alabama. Vector polygons in this data set represent...
Virginia ESI: HABITATS (Habitat Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for submerged aquatic vegetation (SAV) and rare terrestrial plants/communities in Virginia. Vector polygons...
Maryland ESI: INDEX (Index Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries of all hardcopy cartographic products produced as part of the Environmental Sensitivity Index...
Louisiana ESI: FISH (Fish Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for freshwater (inland) fish species in coastal Louisiana. Vector polygons represent water-bodies and other...
Van Maldeghem, Hendrik
1998-01-01
Generalized Polygons is the first book to cover, in a coherent manner, the theory of polygons from scratch. In particular, it fills elementary gaps in the literature and gives an up-to-date account of current research in this area, including most proofs, which are often unified and streamlined in comparison to the versions generally known. Generalized Polygons will be welcomed both by the student seeking an introduction to the subject as well as the researcher who will value the work as a reference. In particular, it will be of great value for specialists working in the field of generalized polygons (which are, incidentally, the rank 2 Tits-buildings) or in fields directly related to Tits-buildings, incidence geometry and finite geometry. The approach taken in the book is of geometric nature, but algebraic results are included and proven (in a geometric way!). A noteworthy feature is that the book unifies and generalizes notions, definitions and results that exist for quadrangles, hexagons, octagons - in the ...
Maldeghem, Hendrik
1998-01-01
This book is intended to be an introduction to the fascinating theory ofgeneralized polygons for both the graduate student and the specialized researcher in the field. It gathers together a lot of basic properties (some of which are usually referred to in research papers as belonging to folklore) and very recent and sometimes deep results. I have chosen a fairly strict geometrical approach, which requires some knowledge of basic projective geometry. Yet, it enables one to prove some typically group-theoretical results such as the determination of the automorphism groups of certain Moufang polygons. As such, some basic group-theoretical knowledge is required of the reader. The notion of a generalized polygon is a relatively recent one. But it is one of the most important concepts in incidence geometry. Generalized polygons are the building bricks of Tits buildings. They are the prototypes and precursors of more general geometries such as partial geometries, partial quadrangles, semi-partial ge ometries, near...
Louisiana ESI: PARISH (Parish Management Area Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains boundaries for parishes in coastal Louisiana. Vector polygons in this data set represent parish management areas. Location-specific type and...
Louisiana ESI: REPTILES (Reptile and Amphibian Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for reptiles and amphibians in coastal Louisiana. Vector polygons represent reptile and amphibian habitats,...
Alabama ESI: HYDRO (Hydrography Lines and Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for Alabama. The...
Southeast Alaska ESI: FISH (Fish Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for estuarine, benthic, and pelagic fish in Southeast Alaska. Vector polygons in this data set represent locations of...
Columbia River ESI: FISH (Fish Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and freshwater fish species in Columbia River. Vector polygons in this...
Virginia ESI: MGT (Management Area Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains boundaries for management areas, national parks, state and local parks, and wildlife refuges in Virginia. Vector polygons in this data set...
Western Alaska ESI: HABITATS (Habitat Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for submerged aquatic vegetation (SAV) in Western Alaska. Vector polygons in this data set represent...
Virginia ESI: HYDRO (Hydrography Lines and Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for Virginia. The...
Maryland ESI: HYDRO (Hydrography Lines and Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for Maryland. The...
American Samoa ESI: FISH (Fish Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for reef, pelagic, benthic, and estuarine fish species in American Samoa. Vector polygons in this data set...
Hawaii ESI: HYDRO (Hydrology Polygons and Lines)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector arcs and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for Hawaii. The...
Maryland ESI: REPTILES (Reptile and Amphibian Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for sea turtles, estuarine turtles, and rare reptiles and amphibians in Maryland. Vector polygons in this...
Southeast Alaska ESI: BIRDS (Bird Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for waterfowl in Southeast Alaska. Vector polygons in this data set represent locations of foraging and rafting...
Hawaii ESI: HABITATS (Habitat and Plant Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for corals, algae, seagrass, and native/rare terrestrial plants in coastal Hawaii. Vector polygons in this...
Columbia River ESI: MGT (Management Area Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive human-use data for Wildlife Refuges, National Forests, and State Parks for the Columbia River area. Vector polygons in this data set...
American Samoa ESI: INVERT (Invertebrate Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for estuarine, reef-associated, and terrestrial invertebrate species in American Samoa. Vector polygons in...
Columbia River ESI: INDEX (Index Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries of all hardcopy cartographic products produced as part of the Environmental Sensitivity Index...
Columbia River ESI: INVERT (Invertebrate Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for clams, oysters, crabs, and other invertebrate species in Columbia River. Vector polygons in this data...
American Samoa ESI: BIRDS (Bird Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for seabirds, wading birds, shorebirds, waterfowl, and gulls and terns in American Samoa. Vector polygons...
American Samoa ESI: INDEX (Index Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries of all the hardcopy cartographic products produced as part of the Environmental Sensitivity Index...
Western Alaska ESI: INVERT (Invertebrate Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine and estuarine invertebrate species in Western Alaska. Vector polygons in this data set represent...
Southeast Alaska ESI: MGT (Management Area Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains management area data for National Parks, Wildlife Refuges, and areas designated as Critical Habitat in Southeast Alaska. Vector polygons in...
Western Alaska ESI: HYDRO (Land Mass Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing coastal hydrography that defines the primary land masses used in the creation of the Environmental Sensitivity...
Louisiana ESI: HYDRO (Hydrography Lines and Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for coastal...
Louisiana ESI: HABITATS (Habitat and Plant Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for coastal habitats in Louisiana. Vector polygons represent various habitats, including marsh types, other...
Lu, Yanyan
2012-08-01
Decomposing a shape into visually meaningful parts comes naturally to humans, but recreating this fundamental operation in computers has been shown to be difficult. Similar challenges have puzzled researchers in shape reconstruction for decades. In this paper, we recognize the strong connection between shape reconstruction and shape decomposition at a fundamental level and propose a method called α-decomposition. The α-decomposition generates a space of decompositions parameterized by α, the diameter of a circle convolved with the input polygon. As we vary the value of α, some structural features appear and disappear quickly while others persist. Therefore, by analyzing the persistence of the features, we can determine better decompositions that are more robust to both geometrical and topological noises. © 2012 Elsevier Ltd. All rights reserved.
Don, Henk
2011-01-01
We study the geometry of billiard orbits on rectangular billiards. A truncated billiard orbit induces a partition of the rectangle into polygons. We prove that thirteen is a sharp upper bound for the number of different areas of these polygons.
Ergodicity of polygonal slap maps
Del Magno, Gianluigi; Lopes Dias, João; Duarte, Pedro; Gaivão, José Pedro
2014-08-01
Polygonal slap maps are piecewise affine expanding maps of the interval obtained by projecting the sides of a polygon along their normals onto the perimeter of the polygon. These maps arise in the study of polygonal billiards with non-specular reflection laws. We study the absolutely continuous invariant probabilities (acips) of the slap maps for several polygons, including regular polygons and triangles. We also present a general method for constructing polygons with slap maps with more than one ergodic acip.
Conversion of raster coded images to polygonal data structures
Nichols, D. A.
1982-01-01
A method is presented for converting polygons coded in raster data structures into conventional vector structures to allow the output of scanner-based data collection systems to be input directly to conventional geographic information systems. The method relies on topological principles to (1) uniquely label each polygon in the image and produce an output image in which each pixel is described by the label of the polygon to which it belongs; (2) create line segment components of polygon boundaries, with nodes labeled and the two adjacent polygons identified; and (3) traverse the polygon boundaries by connecting the appropriate adjacent line segments. The conversion capability makes it possible to design systems which automatically convert to the data structure most appropriate for a particular application.
Alabama ESI: M_MAMMAL (Marine Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for dolphins and manatees in Alabama. Vector polygons in this data set represent marine mammal distribution...
Alabama ESI: T_MAMMAL (Terrestrial Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for Alabama and Perdido Key beach mice in Alabama. Vector polygons in this data set represent the rare...
Bristol Bay, Alaska Subarea ESI: INDEX (Index Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries of all the hardcopy cartographic products produced as part of the Environmental Sensitivity Index...
Guam and the Northern Mariana Islands ESI: HABITATS (Habitat Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for benthic marine habitats and plants in Guam and the Northern Mariana Islands. Vector polygons in this...
Southeast Alaska ESI: T_MAMMAL (Terrestrial Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for brown bears in Southeast Alaska. Vector polygons in this data set represent locations of bear concentrations....
Coastal Resources Atlas: Long Island: REPTILES (Reptile and Amphibian Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for sea turtles, estuarine turtles, and amphibians for Long Island, New York. Vector polygons in this data...
Coastal Resources Atlas: Long Island: FISH (Fish Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and freshwater fish species for Long Island, New York. Vector polygons...
American Samoa ESI: BENTHIC (Benthic Marine Habitat Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for benthic habitats in American Samoa. Vector polygons in this data set represent the distribution of...
North Slope, Alaska ESI: T_MAMMAL (Terrestrial Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for brown bears, caribou, and muskoxen for the North Slope, Alaska. Vector polygons in this data set...
Louisiana ESI: T_MAMMAL (Terrestrial Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for terrestrial mammals in Louisiana. Vector polygons in this data set represent terrestrial mammal...
Maryland ESI: M_MAMMAL (Marine Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for seals, whales, porpoise, and dolphin in Maryland. Vector polygons in this data set represent marine...
Western Alaska ESI: T_MAMMAL (Terrestrial Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for brown bears in Western Alaska. Vector polygons in this data set represent terrestrial mammal...
Southeast Alaska ESI: M_MAMMAL (Marine Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for seals, porpoises, otters, and whales in coastal Southeast Alaska. Vector polygons in this data set represent...
Columbia River ESI: M_MAMMAL (Marine Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for Steller sea lions, harbor seals, and California sea lions in Columbia River. Vector polygons in this...
Guam and the Northern Mariana Islands ESI: REPTILES (Reptile Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for sea turtles in Guam and the Northern Mariana Islands. Vector polygons in this data set represent turtle...
Louisiana ESI: LG_INDEX (Large Index Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries of all the hardcopy cartographic products produced as part of the Environmental Sensitivity Index...
Maryland ESI: T_MAMMAL (Terrestrial Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for river otters in Maryland. Vector polygons in this data set represent the terrestrial mammal...
Coastal Resources Atlas: Long Island: INVERT (Invertebrate Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for coastal, estuarine, and marine invertebrate species for Long Island, New York. Vector polygons in this...
Alabama ESI: ESI (Shoreline Types - Lines and Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing the shoreline and coastal habitats for Alabama, classified according to the Environmental Sensitivity...
Guam and the Northern Mariana Islands ESI: INDEX (Index Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries of all hardcopy cartographic products produced as part of the Environmental Sensitivity Index...
American Samoa ESI: HYDRO (Hydrography Lines and Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for American...
Western Alaska ESI: M_MAMMAL (Marine Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for seals, whales, dolphins, walruses, and Steller sea lions in Western Alaska. Vector polygons in this...
Memorials (Polygons) at Little Bighorn Battlefield National Monument, Montana
National Park Service, Department of the Interior — This is a vector polygon file showing the memorials at Little Bighorn Battlefield National Monument (LIBI). The coordinates for this dataset were collected using a...
Columbia River ESI: HYDRO (Hydrography Lines and Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for Columbia...
Columbia River ESI: REPTILES (Reptile and Amphibian Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for western pond turtles and western painted turtles in Columbia River. Vector polygons in this data set...
Virginia ESI: T_MAMMAL (Terrestrial Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for the northern river otter in Virginia. Vector polygons in this data set represent terrestrial mammal...
Louisiana ESI: SM_INDEX (Small Index Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries of all the hardcopy cartographic products produced as part of the Environmental Sensitivity Index...
Bristol Bay, Alaska Subarea ESI: BIOINDEX (Biological Index Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries of the 1:250,000 map boundaries used in the creation of the Environmental Sensitivity Index (ESI)...
Guam and the Northern Mariana Islands ESI: WETLANDS (Wetland Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the coastal wetland habitats for Guam and the Northern Mariana Islands classified according to the Environmental...
Coastal Resources Atlas: Long Island: HYDRO (Hydrography Lines and Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for Long Island,...
American Samoa ESI: REPTILES (Reptile and Amphibian Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for sea turtles in American Samoa. Vector polygons in this data set represent sea turtle nesting and...
North Slope, Alaska ESI: M_MAMMAL (Marine Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for whales, seals, walruses, and polar bears for the North Slope of Alaska. Vector polygons in this data...
Virginia ESI: M_MAMMAL (Marine Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for dolphin, seals, whales, and porpoise in Virginia. Vector polygons in this data set represent marine...
American Samoa ESI: M_MAMMAL (Marine Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for whales and dolphins in American Samoa. Vector polygons in this data set represent marine mammal...
North Slope, Alaska ESI: HYDRO (Hydrography Lines and Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for the North...
Bristol Bay, Alaska Subarea ESI: HYDRO (Hydrography Lines and Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for the Bristol...
Southeast Alaska ESI: HABITATS (Habitat and Plant Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for seagrass habitats in Southeast Alaska. Vector polygons in this data set represent locations of seagrass...
Cook Inlet and Kenai Peninsula, Alaska ESI: FISH (Fish Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for herring spawning areas in Cook Inlet and Kenai Peninsula, Alaska. Vector polygons in this data set represent...
Cook Inlet and Kenai Peninsula, Alaska ESI: INDEX (Index Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries used in the creation of the Environmental Sensitivity Index (ESI) for Cook Inlet and Kenai...
Cook Inlet and Kenai Peninsula, Alaska ESI: INVERT (Invertebrate Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for razor clams in Cook Inlet and Kenai Peninsula, Alaska. Vector polygons in this data set represent locations of...
Southeast Alaska ESI: HYDRO (Hydrography Lines and Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for Southeast...
Columbia River ESI: NWI (National Wetlands Inventory - Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the wetlands of Columbia River classified according to the Environmental Sensitivity Index (ESI) classification...
2016-01-01
Documento que contiene la explicación sobre las temáticas de Sistemas coordenados, Cantidades vectoriales y escalares, Algunas propiedades de los vectores, Componentes de un vector y vectores unitarios
Boolean Operations on Conic Polygons
Yong-Xi Gong; Yu Liu; Lun Wu; Yu-Bo Xie
2009-01-01
An algorithm for Boolean operations on conic polygons is proposed. Conic polygons are polygons consisting of conic segments or bounded conics with directions. Preliminaries of Boolean operations on general polygons are presented. In our algorithm, the intersection points and the topological relationships between two conic polygons are computed. Boundaries are obtained by tracking path and selecting uncrossed boundaries following rule tables to build resulting conic polygons.We define a set of rules for the intersection, union, and subtraction operations on conic polygons. The algorithm considers degeneration cases such as homology, complement, interior, and exterior. The algorithm is also evaluated and implemented.
Pedro Pina
2009-06-01
Full Text Available The presence of water ice on Mars is well established. Some featureson the planet point to the occurrence of processes similar to those that take place in periglacial areas of Earth. One of the clues for this is the existence of small-scale polygonal terrains. In this paper, we present a methodology that aims at the automated identification of polygonal patterns on high-spatial resolution images of the surface of Mars. In the context of the research project TERPOLI, this step will be complemented with a full characterization, in both geometric and topological terms, of thenetworks detected. In this manner, we hope to collect data that will lead to a better understanding of the conditions of formation of the polygons, and of their temporal evolution; namely, we intend to identify different groups of polygons and to compare them with terrestrial examples.
FEMA DFIRM Panel Scheme Polygons
Minnesota Department of Natural Resources — This layer contains information about the Flood Insurance Rate Map (FIRM) panel areas. The spatial entities representing FIRM panels are polygons. The polygon for...
Boeriis, Morten; van Leeuwen, Theo
2017-01-01
This article revisits the concept of vectors, which, in Kress and van Leeuwen’s Reading Images (2006), plays a crucial role in distinguishing between ‘narrative’, action-oriented processes and ‘conceptual’, state-oriented processes. The use of this concept in image analysis has usually focused...... on the most salient vectors, and this works well, but many images contain a plethora of vectors, which makes their structure quite different from the linguistic transitivity structures with which Kress and van Leeuwen have compared ‘narrative’ images. It can also be asked whether facial expression vectors...... should be taken into account in discussing ‘reactions’, which Kress and van Leeuwen link only to eyeline vectors. Finally, the question can be raised as to whether actions are always realized by vectors. Drawing on a re-reading of Rudolf Arnheim’s account of vectors, these issues are outlined...
2005-01-01
14 April 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a typical view of polygon-cracked and pitted surfaces unique to western Utopia Planitia. No other place on Mars has this appearance. Some Mars scientists have speculated that ground ice may be responsible for these landforms. Location near: 42.3oN, 275.6oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Summer
2003-01-01
MGS MOC Release No. MOC2-339, 23 April 2003This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a pattern of polygonal cracks and aligned, elliptical pits in western Utopia Planitia. The picture covers an area about 3 km (about 1.9 mi) wide near 44.9oN, 274.7oW. Sunlight illuminates the scene from the left.
Two-Dimensional (2D) Polygonal Electromagnetic Cloaks
LI Chao; YAO Kan; LI Fang
2009-01-01
Transformation optics offers remarkable control over electromagnetic fields and opens an exciting gateway to design 'invisible cloak devices' recently.We present an important class of two-dimensional (2D) cloaks with polygon geometries.Explicit expressions of transformed medium parameters are derived with their unique properties investigated.It is found that the elements of diagonalized permittivity tensors are always positive within an irregular polygon cloak besides one element diverges to plus infinity and the other two become zero at the inner boundary.At most positions,the principle axes of permittivity tensors do not align with position vectors.An irregular polygon cloak is designed and its invisibility to external electromagnetic waves is numerically verified.Since polygon cloaks can be tailored to resemble any objects,the transformation is finally generalized to the realization of 2D cloaks with arbitrary geometries.
GPC: General Polygon Clipper library
Murta, Alan
2015-12-01
The University of Manchester GPC library is a flexible and highly robust polygon set operations library for use with C, C#, Delphi, Java, Perl, Python, Haskell, Lua, VB.Net and other applications. It supports difference, intersection, exclusive-or and union clip operations, and polygons may be comprised of multiple disjoint contours. Contour vertices may be given in any order - clockwise or anticlockwise, and contours may be convex, concave or self-intersecting, and may be nested (i.e. polygons may have holes). Output may take the form of either polygon contours or tristrips, and hole and external contours are differentiated in the result.
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and brackish/freshwater fish species in North Carolina. Vector polygons...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for the Florida...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains submerged aquatic vegetation (SAV) and corals for the Florida Panhandle. Vector polygons in the data set represent SAV and coral distribution....
National Oceanic and Atmospheric Administration, Department of Commerce — The ESIP data set contains vector polygons representing the shoreline and coastal habitats of the Florida Panhandle, classified according to the Environmental...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine and estuarine invertebrate species in North Carolina. Vector polygons in this data set represent...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for estuarine, benthic, and pelagic fish in the Aleutian Islands, Alaska. Vector polygons in this data set represent...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, and anadromous fish species in Central California. Vector polygons in this data set...
Columbia River ESI: ESI (Environmental Sensitivity Index Shoreline Types - Lines and Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing the shoreline and coastal habitats of Columbia River classified according to the Environmental...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains management area data for National Wildlife Refuges in the Aleutian Islands, Alaska. Vector polygons in this data set represent management...
Sensitivity of Coastal Environments and Wildlife to Spilled Oil: South Florida: FISH (Fish Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine and estuarine fish species in South Florida. Vector polygons in this data set represent fish...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries of all hardcopy cartographic products produced as part of the Environmental Sensitivity Index...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains benthic habitats, including coral reef and hardbottom, seagrass, algae, and others in [for] South Florida. Vector polygons in the data set...
National Oceanic and Atmospheric Administration, Department of Commerce — The ESIP data set contains vector polygons representing the shoreline and coastal habitats of South Florida classified according to the Environmental Sensitivity...
Virginia ESI: ESI (Environmental Sensitivity Index Shoreline Types - Lines and Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing the shoreline and coastal habitats for Virginia, classified according to the Environmental Sensitivity...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine and estuarine invertebrate species in South Florida. Vector polygons in this data set represent...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for South...
Coastal Resources Atlas: Long Island: T_MAMMAL (Terrestrial Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for northern river otter, mink, muskrat, and beaver for Long Island, New York. Vector polygons in this data...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for sea otters and walrus in the Aleutian Islands, Alaska. Vector polygons in this data set represent locations of...
Coastal Resources Atlas: Long Island: M_MAMMAL (Marine Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for seals, whales, and porpoises for Long Island, New York. Vector polygons in this data set represent...
Hawaii ESI: ESI (Environmental Sensitivity Index Shoreline Types - Polygons and Lines)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector arcs and polygons representing the shoreline and coastal habitats of Hawaii classified according to the Environmental Sensitivity Index...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine and estuarine invertebrate species for the Hudson River. Vector polygons in this data set...
Rhode Island, Connecticut, New York, and New Jersey ESI: T_MAMMAL (Terrestrial Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for small mammal species in coastal Rhode Island, Connecticut, New York, and New Jersey. Vector polygons in...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for Northern...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for Mississippi....
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for Southern...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine and estuarine invertebrate species in Northwest Arctic, Alaska. Vector polygons in this data set...
Guam and the Northern Mariana Islands ESI: M_MAMMAL (Marine Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for dolphins in Guam and the Northern Mariana Islands. Vector polygons in this data set represent marine...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, and brackish water invertebrate species in Mississippi. Vector polygons in this data...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for sea turtles, estuarine turtles, and rare reptiles in North Carolina. Vector polygons in this data set...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for benthic habitats in Central California. Vector polygons in this data set represent kelp and eelgrass...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for submerged aquatic vegetation (SAV) in Northwest Arctic, Alaska. Vector polygons in this data set...
National Park Service, Department of the Interior — A vector polygon dataset representing the location of sample clusters of cored trees at Sand Creek Massacre NHS as part of a University of Colorado research study.
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for dolphin and manatees in Mississippi. Vector polygons in this data set represent marine mammal...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for crabs and bivalves in the Aleutian Islands, Alaska. Vector polygons in this data set represent locations of...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for sea turtles, estuarine turtles, and gopher tortoise in Mississippi. Vector polygons in this data set...
American Samoa ESI: ESI (Environmental Sensitivity Index Shoreline Types - Polygons and Lines)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing the shoreline and coastal habitats of American Samoa classified according to the Environmental...
Rhode Island, Connecticut, New York, and New Jersey ESI: INDEX (Index Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries of the U.S. Geological Survey 1:24,000 topographic maps and other map and digital data boundaries...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for rare amphibians, rare reptiles, and sea turtles in Southern California. Vector polygons in this data...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for seagrasses in the Aleutian Islands, Alaska. Vector polygons in this data set represent locations of seagrass...
Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Mississippi: FISH (Fish Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and brackish water fish species in Mississippi. Vector polygons in this...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for sea turtles and estuarine frogs and turtles in Northern California. Vector polygons in this data set...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for amphibians and reptiles in Central California. Vector polygons in this data set represent sea turtle...
Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Hudson River: FISH (Fish Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and freshwater fish species in the Hudson River. Vector polygons in this...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and freshwater fish species in Northern California. Vector polygons in...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing the shoreline and coastal habitats of the Bristol Bay Subarea, classified according to the...
North Slope, Alaska ESI: ESI (Environmental Sensitivity Index Shoreline Types - Lines and Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing the shoreline and coastal habitats for the North Slope of Alaska classified according to the...
Cook Inlet and Kenai Peninsula, Alaska ESI: HYDRO (Hydrography Lines and Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for Cook Inlet...
Guam and the Northern Mariana Islands ESI: HYDRO (Hydrography Lines and Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for Guam and the...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for the Hudson...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for North...
Rhode Island, Connecticut, New York, and New Jersey ESI: HYDRO (Hydrography Lines and Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for Rhode Island,...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for Central...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for kelp, eelgrass, and terrestrial plants in Northern California. Vector polygons in this data set...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for rare plants for the Florida Panhandle. Vector polygons in this data set represent rare plant...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing the shoreline and coastal habitats of Cook Inlet and Kenai Peninsula, Alaska, classified according to...
Cook Inlet and Kenai Peninsula, Alaska ESI: M_MAMMAL (Marine Mammal Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for marine mammals in Cook Inlet and Kenai Peninsula, Alaska. Vector polygons in this data set represent locations of...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for submerged aquatic vegetation (SAV) and rare plants in North Carolina. Vector polygons in the data set...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine and estuarine invertebrate species for the Upper Coast of Texas. Vector polygons in this data...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for endangered plants for the Upper Coast of Texas. Vector polygons in this data set represent occurrence...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, and freshwater fish species for the Upper Coast of Texas. Vector polygons in this...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries of all hardcopy cartographic products produced as part of the Environmental Sensitivity Index...
KIDS COUNT New Hampshire, 2000.
Shemitz, Elllen, Ed.
This Kids Count report presents statewide trends in the well-being of New Hampshire's children. The statistical report is based on 22 indicators of child well-being in 5 interrelated areas: (1) children and families (including child population, births, children living with single parent, and children experiencing parental divorce); (2) economic…
Evacuation of rectilinear polygons
Fekete, Sandor P; Kroeller, Alexander
2010-01-01
We investigate the problem of creating fast evacuation plans for buildings that are modeled as grid polygons, possibly containing exponentially many cells. We study this problem in two contexts: the ``confluent'' context in which the routes to exits remain fixed over time, and the ``non-confluent'' context in which routes may change. Confluent evacuation plans are simpler to carry out, as they allocate contiguous regions to exits; non-confluent allocation can possibly create faster evacuation plans. We give results on the hardness of creating the evacuation plans and strongly polynomial algorithms for finding confluent evacuation plans when the building has two exits. We also give a pseudo-polynomial time algorithm for non-confluent evacuation plans. Finally, we show that the worst-case bound between confluent and non-confluent plans is 2-2/(k+1).
Polygonal Approximation Using an Artificial Bee Colony Algorithm
Shu-Chien Huang
2015-01-01
Full Text Available A polygonal approximation method based on the new artificial bee colony (NABC algorithm is proposed in this paper. In the present method, a solution is represented by a vector, and the objective function is defined as the integral square error between the given curve and its corresponding polygon. The search process, including the employed bee stage, the onlooker bee stage, and the scout bee stage, has been constructed for this specific problem. Most experiments show that the present method when compared with the DE-based method can obtain superior approximation results with less error norm with respect to the original curves.
Soils - Volusia County Soils (Polygons)
NSGIC GIS Inventory (aka Ramona) — Soils: 1:24000 SSURGO Map. Polygon boundaries of Soils in Volusia County, downloaded from SJRWMD and created by NRCS and SJRWMD. This data set is a digital version...
Carpinteria Salt Marsh Habitat Polygons
U.S. Geological Survey, Department of the Interior — We identified five common habitat types in Carpinteria Salt Marsh: channels, pans (flats), marsh, salt flat and upland. We then drew polygons around each habitat...
Control Point Generated PLS - polygons
Minnesota Department of Natural Resources — The Control Point Generated PLS layer contains line and polygon features to the 1/4 of 1/4 PLS section (approximately 40 acres) and government lot level. The layer...
Orthogonal systems of Zernike type in polygons and polygonal facets
Ferreira, Chelo; Navarro, Rafael; Sinusia, Ester Perez
2015-01-01
Zernike polynomials are commonly used to represent the wavefront phase on circular optical apertures, since they form a complete and orthonormal basis on the unit disk. In [Diaz et all, 2014] we introduced a new Zernike basis for elliptic and annular optical apertures based on an appropriate diffeomorphism between the unit disk and the ellipse and the annulus. Here, we present a generalization of this Zernike basis for a variety of important optical apertures, paying special attention to polygons and the polygonal facets present in segmented mirror telescopes. On the contrary to ad hoc solutions, most of them based on the Gram-Smith orthonormalization method, here we consider a piece-wise diffeomorphism that transforms the unit disk into the polygon under consideration. We use this mapping to define a Zernike-like orthonormal system over the polygon. We also consider ensembles of polygonal facets that are essential in the design of segmented mirror telescopes. This generalization, based on in-plane warping of...
Interactive display of polygonal data
Wood, P.M.
1977-10-01
Interactive computer graphics is an excellent approach to many types of applications. It is an exciting method of doing geographic analysis when desiring to rapidly examine existing geographically related data or to display specially prepared data and base maps for publication. One such program is the interactive thematic mapping system called CARTE, which combines polygonal base maps with statistical data to produce shaded maps using a variety of shading symbolisms on a variety of output devices. A polygonal base map is one where geographic entities are described by points, lines, or polygons. It is combined with geocoded data to produce special subject or thematic maps. Shading symbolisms include texture shading for areas, varying widths for lines, and scaled symbols for points. Output devices include refresh and storage CRTs and auxiliary Calcomp or COM hardcopy. The system is designed to aid in the quick display of spatial data and in detailed map design.
The generation algorithm of arbitrary polygon animation based on dynamic correction
Hou Ya Wei
2016-01-01
Full Text Available This paper, based on the key-frame polygon sequence, proposes a method that makes use of dynamic correction to develop continuous animation. Firstly we use quadratic Bezier curve to interpolate the corresponding sides vector of polygon sequence consecutive frame and realize the continuity of animation sequences. And then, according to Bezier curve characteristic, we conduct dynamic regulation to interpolation parameters and implement the changing smoothness. Meanwhile, we take use of Lagrange Multiplier Method to correct the polygon and close it. Finally, we provide the concrete algorithm flow and present numerical experiment results. The experiment results show that the algorithm acquires excellent effect.
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for seals, whales, dolphins, porpoises, sea otters, and sea lions in Northern California. Vector polygons...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing the shoreline and coastal habitats of Northern California, classified according to the Environmental...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for seals, sea lions, whales, dolphins, porpoises, and sea otters in Southern California. Vector polygons...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for terrestrial mammals in Northwest Arctic, Alaska. Vector polygons in this data set represent muskoxen...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for rare/sensitive species occurrences of terrestrial mammals in Central California. Vector polygons in...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for small terrestrial mammals (woodrats, myotis, muskrat, mink) for the Hudson River. Vector polygons in...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for small mammals and elk in Northern California. Vector polygons in this data set represent terrestrial...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for terrestrial mammals in North Carolina. Vector polygons in this data set represent terrestrial mammal...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing the shoreline and coastal habitats of Rhode Island, Connecticut, New York, and New Jersey, classified...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for manatees and bottlenose dolphins in [for] South Florida. Vector polygons in this data set represent...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for rare and threatened/endangered terrestrial mammals in Southern California. Vector polygons in this data...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for dolphins and manatees in for the Florida Panhandle. Vector polygons in this data set represent dolphins...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing coastal wetland habitats for the Hudson River classified according to the Environmental Sensitivity Index (ESI)...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing the shoreline and coastal habitats of Southern California, classified according to the Environmental...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for whales, porpoises, dolphins, manatees, and pinnipeds in North Carolina. Vector polygons in this data...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing the shoreline and coastal habitats of the Aleutian Islands classified according to the Environmental...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for dolphins, porpoises, whales, seals, sea lions, and sea otters in Central California. Vector polygons in...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains commercial fisheries in South Florida. Vector polygons in this data set represent statistical reporting grids used to aggregate commercial...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine mammals (seals) in the Hudson River. Vector polygons in this data set represent marine mammal...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector arcs and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for Northwest...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for beach mice, red wolf, and Florida black bear for the Florida Panhandle. Vector polygons in this data...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for the Upper...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for terrestrial mammals for the Upper Coast of Texas. Vector polygons in this data set represent...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for dolphins and manatees for the Upper Coast of Texas. Vector polygons in this data set represent marine...
Libraries in New Hampshire: MedlinePlus
... this page: https://medlineplus.gov/libraries/newhampshire.html Libraries in New Hampshire To use the sharing features ... enable JavaScript. Berlin White Mountains Community College Fortier Library 2020 Riverside Drive Berlin, NH 03570-3799 603- ...
Polygonal instabilities on interfacial vorticities
Labousse, Matthieu
2015-01-01
We report the results of a theoretical investigation of the stability of a toroidal vortex bound by an interface. Two distinct instability mechanisms are identified that rely on, respectively, surface tension and fluid inertia, either of which may prompt the transformation from a circular to a polygonal torus. Our results are discussed in the context of three experiments, a toroidal vortex ring, the hydraulic jump, and the hydraulic bump.
Polygon Exploration with Discrete Vision
Fekete, Sandor P
2008-01-01
With the advent of autonomous robots with two- and three-dimensional scanning capabilities, classical visibility-based exploration methods from computational geometry have gained in practical importance. However, real-life laser scanning of useful accuracy does not allow the robot to scan continuously while in motion; instead, it has to stop each time it surveys its environment. This requirement was studied by Fekete, Klein and Nuechter for the subproblem of looking around a corner, but until now has not been considered in an online setting for whole polygonal regions. We give the first algorithmic results for this important algorithmic problem that combines stationary art gallery-type aspects with watchman-type issues in an online scenario: We demonstrate that even for orthoconvex polygons, a competitive strategy can be achieved only for limited aspect ratio A (the ratio of the maximum and minimum edge length of the polygon), i.e., for a given lower bound on the size of an edge; we give a matching upper boun...
The Fiscal Impacts of School Choice in New Hampshire
Gottlob, Brian J.
2004-01-01
This study addresses the fiscal impacts of school choice in New Hampshire. The author uses one example from the 2003 New Hampshire legislative session to illustrate the fiscal impacts of school choice on New Hampshire and its communities. He develops a unique database of individual and household level responses from the 2000 Census of New…
Sequential Stochastic Construction of Random Polygons.
1982-06-10
clearly geerated by notions of the form T (x,y) 1-+ (Xz* * for (x* y C 2" . This notion sends (1.8) into x coo * + y sin *- (p-x coo -y sin ) = 0 Thus Z ...n-1)) . . . 34 2.7. The Joint Density of Z (n) - The Curling Process . . . . . . 40 CHAPTER 3 POLYGON DISTRIBUTIONS...Joint Density of Z (N) of Polygons .. ........ 47 3.4. The Polygon Density In Isotropicp ............ 31 I . .. . .. .. . . . . . .. ... . . . . . , m
Carpinteria salt marsh habitat polygons
Lafferty, Kevin D.; Dunham, Eleca J.; Mancini, Frank T.; Stewart, Tara E.; Hechinger, Ryan F.
2017-01-01
We identified five common habitat types in Carpinteria Salt Marsh: channels, pans (flats), marsh, salt flat and upland. We then drew polygons around each habitat type identified from a registered and orthorectified aerial photograph and created a GIS shapefile. Polygons were ground-truthed in the field. From these habitat polygons, one can use GIS applications to estimate the area of each habitat type in this estuary. These data support the following publications: Kuris, Armand M., et al. "Ecosystem energetic implications of parasite and free-living biomass in three estuaries." Nature 454.7203 (2008): 515-518.Hechinger, Ryan F., Kevin D. Lafferty, Andy P. Dobson, James H. Brown, and Armand M. Kuris. "A common scaling rule for abundance, energetics, and production of parasitic and free-living species." Science 333, no. 6041 (2011): 445-448.Hechinger, Ryan F., Kevin D. Lafferty, John P. McLaughlin, Brian L. Fredensborg, Todd C. Huspeni, Julio Lorda, Parwant K. Sandhu et al. "Food webs including parasites, biomass, body sizes, and life stages for three California/Baja California estuaries." Ecology 92, no. 3 (2011): 791-791.Buck, J.C., Hechinger, R.F., Wood, A.C., Stewart, T.E., Kuris, A.M., and Lafferty, K.D., "Host density increases parasite recruitment but decreases host risk in a snail-trematode system." Manuscript submitted for publication. Lafferty, K.D., Stewart, T.E., and Hechinger, R.F. (in press). Bird distribution surveys at Carpinteria Salt Marsh, California USA, January 2012 to March 2013: U.S. Geological Survey data release, http://dx.doi.org/10.5066/F7F47M95.
Farthest-Polygon Voronoi Diagrams
Cheong, Otfried; Glisse, Marc; Gudmundsson, Joachim; Hornus, Samuel; Lazard, Sylvain; Lee, Mira; Na, Hyeon-Suk
2010-01-01
Given a family of k disjoint connected polygonal sites in general position and of total complexity n, we consider the farthest-site Voronoi diagram of these sites, where the distance to a site is the distance to a closest point on it. We show that the complexity of this diagram is O(n), and give an O(n log^3 n) time algorithm to compute it. We also prove a number of structural properties of this diagram. In particular, a Voronoi region may consist of k-1 connected components, but if one component is bounded, then it is equal to the entire region.
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing the shoreline and coastal habitats of Northwest Arctic, Alaska classified according to the...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries of all hardcopy cartographic products produced as part of the Environmental Sensitivity Index...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for Puget Sound...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine and estuarine vegetation in Puget Sound and Strait of Juan de Fuca, Washington. Vector polygons...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for forage fish in Puget Sound and Strait of Juan de Fuca, Washington. Vector polygons in this data set...
Polygons on a rotating fluid surface
Jansson, Thomas R.N.; Haspang, Martin P.; Jensen, Kåre H.;
2006-01-01
rotating rigidly with a speed different from that of the plate. With water, we have observed polygons with up to 6 corners. It has been known for many years that such flows are prone to symmetry breaking, but apparently the polygonal surface shapes have never been observed. The creation of rotating...
Nonlinear regimes on polygonal hydraulic jumps
Rojas, Nicolas
2016-11-01
This work extends previous leading and higher order results on the polygonal hydraulic jump in the framework of inertial lubrication theory. The rotation of steady polygonal jumps is observed in the transition from one wavenumber to the next one, induced by a change in height of an external obstacle near the outer edge. In a previous publication, the study of stationary polygons is considered under the assumption that the reference frame rotates with the polygons when the number of corners change, in order to preserve their orientation. In this research work I provide a Hamiltonian approach and the stability analysis of the nonlinear oscillator that describe the polygonal structures at the jump interface, in addition to a perturbation method that enables to explain, for instance, the diversity of patterns found in experiments. GRASP, Institute of Physics, University of Liege, Belgium.
Polygonal Ridge Networks on Mars
Kerber, Laura; Dickson, James; Grosfils, Eric; Head, James W.
2016-10-01
Polygonal ridge networks, also known as boxwork or reticulate ridges, are found in numerous locations and geological contexts across Mars. While networks formed from mineralized fractures hint at hot, possibly life-sustaining circulating ground waters, networks formed by impact-driven clasting diking, magmatic dikes, gas escape, or lava flows do not have the same astrobiological implications. Distinguishing the morphologies and geological context of the ridge networks sheds light on their potential as astrobiological and mineral resource sites of interest. The most widespread type of ridge morphology is characteristic of the Nili Fossae and Nilosyrtis region and consists of thin, criss-crossing ridges with a variety of heights, widths, and intersection angles. They are found in ancient Noachian terrains at a variety of altitudes and geographic locations and may be a mixture of clastic dikes, brecciated dikes, and mineral veins. They occur in the same general areas as valley networks and ancient lake basins, but they are not more numerous where these features are concentrated, and can appear in places where they morphologies are absent. Similarly, some of the ridge networks are associated with hydrated mineral detections, but some occur in locations without detections. Smaller, light-toned ridges of variable widths have been found in Gale Crater and other rover sites and are interpreted to be smaller version of the Nili-like ridges, in this case formed by the mineralization of fractures. This type of ridge is likely to be found in many other places on Mars as more high-resolution data becomes available. Hellas Basin is host to a third type of ridge morphology consisting of large, thick, light-toned ridges forming regular polygons at several superimposed scales. While still enigmatic, these are most likely to be the result of sediment-filled fractures. The Eastern Medusae Fossae Formation contains large swaths of a fourth, previously undocumented, ridge network type
Mixed FEM for Second Order Elliptic Problems on Polygonal Meshes with BEM-Based Spaces
Efendiev, Yalchin
2014-01-01
We present a Boundary Element Method (BEM)-based FEM for mixed formulations of second order elliptic problems in two dimensions. The challenge, we would like to address, is a proper construction of H(div)-conforming vector valued trial functions on arbitrary polygonal partitions of the domain. The proposed construction generates trial functions on polygonal elements which inherit some of the properties of the unknown solution. In the numerical realization, the relevant local problems are treated by means of boundary integral formulations. We test the accuracy of the method on two model problems. © 2014 Springer-Verlag.
Degenerate polygonal tilings in simple animal tissues
Ziherl, Primoz; Hocevar, Ana
2009-03-01
We study 2D polygonal tilings as models of the en-face structure of single-layer biological tissues. Using numerical simulations, we explore the phase diagram of equilibrium tilings of equal-area, equal-perimeter convex polygons whose energy is independent of their shape. We identify 3 distinct phases, which are all observed in simple epithelial tissues: The disordered phase of polygons with 4-9 sides, the hexatic phase, and the hexagonal phase with perfect 6-fold coordination. We quantify their structure using Edwards' statistical mechanics of cellular systems.
Optimal Polygonal Representation of Planar Graphs
Duncan, Christian A; Hu, Yifan; Kaufmann, Michael; Kobourov, Stephen G
2011-01-01
In this paper, we consider the problem of representing graphs by polygons whose sides touch. We show that at least six sides per polygon are necessary by constructing a class of planar graphs that cannot be represented by pentagons. We also show that the lower bound of six sides is matched by an upper bound of six sides with a linear-time algorithm for representing any planar graph by touching hexagons. Moreover, our algorithm produces convex polygons with edges having at most three slopes and with all vertices lying on an O(n)xO(n) grid.
Federal Geographic Data Committee — The SMA implementation is comprised of one feature dataset, with several polygon feature classes, rather than a single feature class. SurfaceManagementAgency: The...
Finding the Most Uniform Changes in Vowel Polygon Caused by Psychological Stress
M. Stanek
2015-06-01
Full Text Available Using vowel polygons, exactly their parameters, is chosen as the criterion for achievement of differences between normal state of speaker and relevant speech under real psychological stress. All results were experimentally obtained by created software for vowel polygon analysis applied on ExamStress database. Selected 6 methods based on cross-correlation of different features were classified by the coefficient of variation and for each individual vowel polygon, the efficiency coefficient marking the most significant and uniform differences between stressed and normal speech were calculated. As the best method for observing generated differences resulted method considered mean of cross correlation values received for difference area value with vector length and angle parameter couples. Generally, best results for stress detection are achieved by vowel triangles created by /i/-/o/-/u/ and /a/-/i/-/o/ vowel triangles in formant planes containing the fifth formant F5 combined with other formants.
Analytical approach of laser beam propagation in the hollow polygonal light pipe.
Zhu, Guangzhi; Zhu, Xiao; Zhu, Changhong
2013-08-10
An analytical method of researching the light distribution properties on the output end of a hollow n-sided polygonal light pipe and a light source with a Gaussian distribution is developed. The mirror transformation matrices and a special algorithm of removing void virtual images are created to acquire the location and direction vector of each effective virtual image on the entrance plane. The analytical method is demonstrated by Monte Carlo ray tracing. At the same time, four typical cases are discussed. The analytical results indicate that the uniformity of light distribution varies with the structural and optical parameters of the hollow n-sided polygonal light pipe and light source with a Gaussian distribution. The analytical approach will be useful to design and choose the hollow n-sided polygonal light pipe, especially for high-power laser beam homogenization techniques.
Region 9 NPL Sites (Superfund Sites) Polygons
U.S. Environmental Protection Agency — NPL site POLYGON locations for the US EPA Region 9. NPL (National Priorities List) sites are hazardous waste sites that are eligible for extensive long-term cleanup...
Comic image understanding based on polygon detection
Li, Luyuan; Wang, Yongtao; Tang, Zhi; Liu, Dong
2013-01-01
Comic image understanding aims to automatically decompose scanned comic page images into storyboards and then identify the reading order of them, which is the key technique to produce digital comic documents that are suitable for reading on mobile devices. In this paper, we propose a novel comic image understanding method based on polygon detection. First, we segment a comic page images into storyboards by finding the polygonal enclosing box of each storyboard. Then, each storyboard can be represented by a polygon, and the reading order of them is determined by analyzing the relative geometric relationship between each pair of polygons. The proposed method is tested on 2000 comic images from ten printed comic series, and the experimental results demonstrate that it works well on different types of comic images.
Region 9 NPL Site (Polygons) 2015
U.S. Environmental Protection Agency — NPL site POLYGON locations for the US EPA Region 9. NPL (National Priorities List) sites are hazardous waste sites that are eligible for extensive long-term cleanup...
Region 9 NPL Site Polygons - 2014
U.S. Environmental Protection Agency — NPL site POLYGON locations for the US EPA Region 9. NPL (National Priorities List) sites are hazardous waste sites that are eligible for extensive long-term cleanup...
From Newton's bucket to rotating polygons
Bach, B.; Linnartz, E. C.; Vested, Malene Louise Hovgaard;
2014-01-01
We present an experimental study of 'polygons' forming on the free surface of a swirling water flow in a partially filled cylindrical container. In our set-up, we rotate the bottom plate and the cylinder wall with separate motors. We thereby vary rotation rate and shear strength independently...... the phase diagram spanned by the two rotational frequencies at a given water filling height and find polygons in a regime, where the two frequencies are sufficiently different and, predominantly, when they have opposite signs. In addition to the extension of the family of polygons found with the stationary...... cylinder, we find a new family of smaller polygons for larger rotation rates of the cylinder, opposite to that of the bottom plate. Further, we find a 'monogon', a figure with one corner, roughly an eccentric circle rotating in the same sense as the cylinder. The case where only the bottom plate...
Anisotropic rectangular metric for polygonal surface remeshing
Pellenard, Bertrand
2013-06-18
We propose a new method for anisotropic polygonal surface remeshing. Our algorithm takes as input a surface triangle mesh. An anisotropic rectangular metric, defined at each triangle facet of the input mesh, is derived from both a user-specified normal-based tolerance error and the requirement to favor rectangle-shaped polygons. Our algorithm uses a greedy optimization procedure that adds, deletes and relocates generators so as to match two criteria related to partitioning and conformity.
Devonian brachiopods from the sillimanite zone, mount moosilauke, new hampshire.
Boucot, A J; Rumble, D
1978-07-28
Devonian brachiopods, identifiable at the generic level, have been recovered from calc-silicate rocks more intensely metamorphosed and metasomatized than any other known fossil occurrence. The fossils are a key stratigraphic link between granulite facies rocks of central New Hampshire and fossiliferous rocks of western New Hampshire and Maine.
The Results of the New Hampshire Education Funding Reform.
Gottlob, Brian J.
This report highlights research that examined education finance data for the 1998-99 school year, the year prior to the introduction of finance reforms in New Hampshire, and the 1999-00 to 2001-02 school years, the 3 years following the introduction of reform. Following are some of the conclusions about New Hampshire's education finance reform.…
Aircraft recognition based on the discrepancy of polygon intersection area
Deng, Xiujian; Wang, Yanfang; Feng, Qi
2017-01-01
In this paper, a new algorithm that based on discrepancy of polygon intersection area for aircraft recognition is presented. The recognition algorithm process involves three parts: generating polygon of aircraft, placing overlapping plane polygons and computing the area of total intersecting polygons. For the purpose of getting the polygon of aircraft, the picture that was ready to be recognized has gone through a series of pre-processing and the smallest circumference polygon algorithm was used to get approximate polygon of the target contour. To make the two compared polygons have the approximate area, the similar principle was utilized. The matching procedure was divided into four steps including computing intersecting points, computing polygon intersecting sets, computing the intersecting area and getting the intersecting rate to recognize the aircraft. The data structure of algorithm is based on doubly liked list principle. A mass of simulations illustrate that the proposed algorithm is effective and reasonable.
2010-06-21
... Energy Regulatory Commission Hampshire Paper Company; Notice Rejecting Application, Waiving Regulations, and Soliciting Applications June 15, 2010. On June 2, 2010, Hampshire Paper Company (Hampshire Paper... filed and is hereby rejected.\\1\\ \\1\\ Hampshire Paper was issued a major license for the project on June...
Sassenroth, Cynthia; Hauber, Ernst; Schmitz, Nicole; de Vera, Jean Pierre
2017-04-01
Polygonally fractured ground is widespread at middle and high latitudes on Mars. The latitude-dependence and the morphologic similarity to terrestrial patterned ground in permafrost regions may indicate a formation as thermal contraction cracks, but the exact formation mechanisms are still unclear. In particular, it is debated whether freeze-thaw processes and liquid water are required to generate the observed features. This study quantitatively investigates polygonal networks in ice-free parts of continental Antarctica to help distinguishing between different hypotheses of their origin on Mars. The study site is located in the Helliwell Hills in Northern Victoria Land ( 71.73°S/161.38°E) and was visited in the framework of the GANOVEX XI expedition during the austral summer of 2015/2016. The local bedrock consists mostly of sediments (sandstones) of the Beacon Supergroup and mafic igneous intrusions (Ferrar Dolerites). The surfaces are covered by glacial drift consisting of clasts with diverse lithologies. Thermal contraction cracks are ubiquitous. We mapped polygons in the northern part of Helliwell Hills in a GIS environment on the basis of high-resolution satellite images with a pixel size of 50 cm. The measured spatial parameters include polygon area, perimeter, length, width, circularity and aspect. We also analyzed the connectivity of enclosed polygons within a polygon network. The polygons do not display significant local relief, but overall the polygon centers are slightly higher than the bounding cracks (i.e. high-center polygons). Sizes of polygons can vary widely, dependent on the geographical location, between 10m2 and >900m2. In planar and level areas, thermal contraction cracks tend to be well connected as hexagonal or irregular polygonal networks without a preferred alignment. In contrast, polygonal networks on slopes form elongated, orthogonal primary cracks, which are either parallel or transverse to the steepest topographic gradient. During
Equipartitioning and balancing points of polygons
Shunmugam Pillay
2010-07-01
Full Text Available The centre of mass G of a triangle has the property that the rays to the vertices from G sweep out triangles having equal areas. We show that such points, termed equipartitioning points in this paper, need not exist in other polygons. A necessary and sufficient condition for a quadrilateral to have an equipartitioning point is that one of its diagonals bisects the other. The general theorem, namely, necessary and sufficient conditions for equipartitioning points for arbitrary polygons to exist, is also stated and proved. When this happens, they are in general, distinct from the centre of mass. In parallelograms, and only in them, do the two points coincide.
Random packing of regular polygons and star polygons on a flat two-dimensional surface.
Cieśla, Michał; Barbasz, Jakub
2014-08-01
Random packing of unoriented regular polygons and star polygons on a two-dimensional flat continuous surface is studied numerically using random sequential adsorption algorithm. Obtained results are analyzed to determine the saturated random packing ratio as well as its density autocorrelation function. Additionally, the kinetics of packing growth and available surface function are measured. In general, stars give lower packing ratios than polygons, but when the number of vertexes is large enough, both shapes approach disks and, therefore, properties of their packing reproduce already known results for disks.
Sequential and Parallel Algorithms for Finding a Maximum Convex Polygon
Fischer, Paul
1997-01-01
such a polygon which is maximal with respect to area can be found in time O(n³ log n). With the same running time one can also find such a polygon which contains a maximum number of positive points. If, in addition, the number of vertices of the polygon is restricted to be at most M, then the running time...
SRB Measures for Polygonal Billiards with Contracting Reflection Laws
Del Magno, Gianluigi; Lopes Dias, João; Duarte, Pedro; Gaivão, José Pedro; Pinheiro, Diogo
2014-07-01
We prove that polygonal billiards with contracting reflection laws exhibit hyperbolic attractors with countably many ergodic SRB measures. These measures are robust under small perturbations of the reflection law, and the tables for which they exist form a generic set in the space of all convex polygons. Specific polygonal tables are studied in detail.
Fair Partitions of Polygons: An Elementary Introduction
R Nandakumar; N Ramana Rao
2012-08-01
We introduce the question: Given a positive integer , can any 2D convex polygonal region be partitioned into convex pieces such that all pieces have the same area and the same perimeter? The answer to this question is easily `yes’ for =2. We give an elementary proof that the answer is `yes’ for =4 and generalize it to higher powers of 2.
Polygon Subtraction in 2 or 3 Dimensions
Wilson, John E.
2013-10-01
When searching for computer code to perform the ubiquitous task of subtracting one polygon from another, it is difficult to find real examples and detailed explanations. This paper outlines the step-by-step process necessary to accomplish this basic task.
A characterization of quasi-rational polygons
Bedaride, Nicolas
2012-11-01
The aim of this paper is to study quasi-rational polygons related to the outer billiard. We compare different notions introduced in Gutkin and Simányi (1992 Commun. Math. Phys. 143 431-49) and Schwartz (2009 Outer Billiards on Kites (Annals of Mathematics Studies vol 171) (Princeton, NJ: Princeton University Press)) and make a synthesis of them.
Aerial target recognition using MRA, GVF snakes, and polygon approximation
Lu, Zhen Z.; Zhang, Taiyi; Xu, Jian
2003-04-01
The traditional method to extract target contour from aerial target image is changing the aerial image into a gray level image with multiple thresholds or binary image with single threshold. From the edge of target, contour can be extracted according to the changed value. The traditional method is useful only when contrast between target and background is in the proper degree. Snakes are curves defined within an image domain that can move under the influence of internal force coming from within the curve itself and external forces are defined so that the snake will conform to an object boundary or other desired features within an image. Snakes have been proved an effective method and widely used in image processing and computer vision. Snakes synthesize parametric curves within an image domain and allow them to move toward desired edges. Particular advantages of the GVF(Gradient Vector Flow) snakes over a traditional snakes are its insensitivity to initialization and its ability to move into boundary concavities. Its initializations can be inside, outside, or across the object"s boundary. The GVF snake does not need prior knowledge about whether to shrink or expand toward the boundary. This increased capture range is achieved through a diffusion process that does not blur the edges of themselves. Affected by the light from different incident angle, the brightness of aerial target surface changed greatly in a complicate mode. So the GVF snakes is not fast, accurate and effective all the time for this kind of images. A new contour extracting method, GVF Snakes Combined with wavelet multi-resolution Analysis is proposed in this paper. In this algorithm, bubble wavelet is used iteratively to do the multi resolution analysis in the order of degressive scale before GVF Snakes is used every time to extract accurate contour of target. After accurate contour is extracted, polygon approximation is used to extract characteristics to realize the recognition of aerial target
The cohomology ring of polygon spaces
Hausmann, J C; Hausmann, Jean-Claude; Knutson, Allen
1997-01-01
We compute the integer cohomology rings of the ``polygon spaces'' introduced in [Hausmann,Klyachko,Kapovich-Millson]. This is done by embedding them in certain toric varieties; the restriction map on cohomology is surjective and we calculate its kernel using ideas from the theory of Gröbner bases. Since we do not invert the prime 2, we can tensor with Z/2; halving all degrees we show this produces the Z/2 cohomology rings of planar polygon spaces. In the equilateral case, where there is an action of the symmetric group permuting the edges, we show that the induced action on the integer cohomology is _not_ the standard one, despite it being so on the rational cohomology [Kl]. Finally, our formulae for the Poincaré polynomials are more computationally effective than those known [Kl].
A polygonal method for haptic force generation
Anderson, T. [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Electrical and Computer Engineering]|[Sandia National Labs., Albuquerque, NM (United States)
1996-12-31
Algorithms for computing forces and associated surface deformations (graphical and physical) are given, which, together with a force feedback device can be used to haptically display virtual objects. The Bendable Polygon algorithm, created at Sandia National Labs and the University of New Mexico, for visual rendering of computer generated surfaces is also presented. An implementation using the EIGEN virtual reality environment, and the PHANToM (Trademark) haptic interface, is reported together with suggestions for future research.
Non-convex polygons clustering algorithm
Kruglikov Alexey
2016-01-01
Full Text Available A clustering algorithm is proposed, to be used as a preliminary step in motion planning. It is tightly coupled to the applied problem statement, i.e. uses parameters meaningful only with respect to it. Use of geometrical properties for polygons clustering allows for a better calculation time as opposed to general-purpose algorithms. A special form of map optimized for quick motion planning is constructed as a result.
Searching a Polygonal Region by Two Guards
Xue-Hou Tan; Bo Jiang
2008-01-01
We study the problem of searching for a mobile intruder in a polygonal region P by two guards. The objective is to decide whether there should exist a search schedule for the two guards to detect the intruder, no matter how fast the intruder moves, and if so, generate a search schedule. During the search, the two guards are required to walk on the boundary of P continuously and be mutually visible all the time. We present a characterization of the class of polygons searchable by two guards in terms of non-redundant components, and thus solve a long-standing open problem in computational geometry.Also, we give an optimal O(n) time algorithm to determine the two-guard searchability in a polygon, and an O(n log n + m) time algorithm to generate a search schedule, if it exists, where n is the number of vertices of P and m (≤ n2) is the number of search instructions reported.
The Hausdorff core problem on simple polygons
Reza Dorrigiv
2014-02-01
Full Text Available A polygon \\(Q\\ is a \\(k\\-bounded Hausdorff Core of a polygon \\(P\\ if \\(P\\ contains \\(Q\\, \\(Q\\ is convex, and the Hausdorff distance between \\(P\\ and \\(Q\\ is at most \\(k\\. A Hausdorff Core of \\(P\\ is a \\(k\\-bounded Hausdorff Core of \\(P\\ with the minimum possible value of \\(k\\, which we denote \\(k_{\\min}\\. Given any \\(k\\ and any \\(\\varepsilon\\gt 0\\, we describe an algorithm for computing a \\(k'\\-bounded Hausdorff Core (if one exists in \\(O(n^3+n^2\\varepsilon^{-4}(\\log n+ \\varepsilon^{-2}\\ time, where \\(k'\\lt k+d_{\\text{rad}}\\cdot\\varepsilon\\ and \\(d_{\\text{rad}}\\ is the radius of the smallest disc that encloses \\(P\\ and whose center is in \\(P\\. We use this solution to provide an approximation algorithm for the optimization Hausdorff Core problem which results in a solution of size \\(k_{\\min}+d_{\\text{rad}}\\cdot\\varepsilon\\ in \\(O(\\log(\\varepsilon^{-1}(n^3+n^2\\varepsilon^{-4}(\\log n+ \\varepsilon^{-2}\\ time. Finally, we describe an approximation scheme for the \\(k\\-bounded Hausdorff Core problem which, given a polygon \\(P\\, a distance \\(k\\, and any \\(\\varepsilon\\gt 0\\, answers true if there is a \\(((1+\\varepsilonk\\-bounded Hausdorff Core and false if there is no \\(k\\-bounded Hausdorff Core. The running time of the approximation scheme is in \\(O(n^3+n^2\\varepsilon^{-4}(\\log n+ \\varepsilon^{-2}\\.
Matching a statistical pressure snake to a four-sided polygon and estimating the polygon corners.
Schaub, Hanspeter (ORION International Technologies, Albuquerque, NM); Wilson, Chris C.
2004-05-01
Given a video image source, a statistical pressure snake is able to track a color target in real time. This report presents an algorithm that exploits the one-dimensional nature of the visual snake target outline. If the target resembles a four-sided polygon, then the four polygon sides are identified by mapping all image snake point coordinates into Hough space where lines become points. After establishing that four dominant lines are present in snake contour, the polygon corner points are estimated. The computation burden of this algorithm is of the N logN type. The advantage of this method is that it can provide real-time target corner estimates, even if the corners themselves might be occluded.
Silvia Manduca Trapp
Full Text Available The present study aimed to determine the types of hemoglobin in Hampshire Down crossbreed sheep, and verify that this locus is in Hardy-Weinberg equilibrium. There have been collected 46 blood samples of healthy Hampshire Down crossbreed sheep. These samples were used to separate the hemoglobin per electrophoresis. The electrophoresis of the hemoglobin revealed a slow band characterized as hemoglobin A (HbAA, a fast band characterized as hemoglobin B (HbBB and two bands in the heterozygous hemoglobin A and B (HbAB. The HbAB type was the most frequently one, followed by hemoglobin A (HbAA and B (HbBB. The genotypic frequency of individuals BB, AB and AA were 36,95; 54,35 and 8,70% respectively. The allelic frequency of A and B were respectively 35,87% and 64,13%.. The qui square test (?2 = 0.859 and p = 0.6509 confirmed that the tested locus is in Hardy-Weinberg equilibrium.O presente trabalho teve como objetivo determinar os tipos de hemoglobinas em ovinos Hampshire Down e verificar se este locus encontra-se em equilíbrio de Hardy-Weinberg. Foram coletadas 46 amostras de sangue de ovinos Hampshire Down, considerados clinicamente sadios. Estas amostras foram utilizadas para a separação das hemoglobinas por eletroforese. A eletroforese das hemoglobinas revelou uma banda lenta caracterizada como hemoglobina B (HbBB, uma banda rápida caracterizada como hemoglobina A (HbAA e duas bandas no heterozigoto para hemoglobinas A e B (HbAB. A variante HbAB foi a mais freqüentemente encontrada, seguida pela hemoglobina A (HbAA e B (HbBB. A freqüência genotípica dos indivíduos BB, AB e AA foram 36,95; 54,35 e 8,70% respectivamente. A freqüência alélica de A e B foram respectivamente 35,87% e 64,13%. Pelo teste do qui-quadrado realizado (?2 = 0,859 e p=0,6509 confirmou-se que o locus testado está em equilíbrio de Hardy-Weinberg.
Polygons in restricted geometries subjected to infinite forces
Beaton, N. R.; Eng, J. W.; Soteros, C. E.
2016-10-01
We consider self-avoiding polygons in a restricted geometry, namely an infinite L × M tube in {{{Z}}}3. These polygons are subjected to a force f, parallel to the infinite axis of the tube. When f\\gt 0 the force stretches the polygons, while when f\\lt 0 the force is compressive. We obtain and prove the asymptotic form of the free energy in both limits f\\to +/- ∞ . We conjecture that the f\\to -∞ asymptote is the same as the limiting free energy of ‘Hamiltonian’ polygons, polygons which visit every vertex in a L× M× N box. We investigate such polygons, and in particular use a transfer-matrix methodology to establish that the conjecture is true for some small tube sizes. Dedicated to Anthony J Guttmann on the occasion of his 70th birthday.
Polygon Morphing and Its Application in Orebody Modeling
Hacer İlhan
2012-01-01
Full Text Available Three different polygon morphing methods are examined. The first one is based on the utilization of the trimmed skeleton of the symmetric difference of the source and target polygons as an intermediate polygon. The second one reduces the problem to the problem of morphing compatible planar triangulations and utilizes the representation of planar triangulations as a matrix constructed using barycentric coordinates of the planar triangulation's vertices relative to their neighbors. The third and last one describes the polygon by the parametric curve representation based on estimated Fourier parameters and thus transfers the morphing process to Fourier parametric space. The different features and comparative results of these methods are shown by the tests with different examples. These methods are used for generating a set of polygonal sections from two nonplanar polygonal sections which are nearly planar in 3D before constructing a three-dimensional object from these nonplanar sections.
Genome-wide identification of quantitative trait loci in a cross between Hampshire and Landrace II
Markljung, Ellen; Braunschweig, Martin H.; Karlskov-Mortensen, Peter;
2008-01-01
to identifying markers that can be used in MAS. In this study, Landrace and Hampshire intercross and backcross families were used to investigate meat quality traits. Hampshire pigs are commonly used as sthe sire line in commercial pig breeding. This is the first time a pedigree including Hampshire pigs has been...
Cost-Effectiveness Analysis of the Residential Provisions of the 2015 IECC for New Hampshire
Mendon, Vrushali V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zhao, Mingjie [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Taylor, Zachary T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Poehlman, Eric A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
2016-02-15
The 2015 IECC provides cost-effective savings for residential buildings in New Hampshire. Moving to the 2015 IECC from the 2010 New Hampshire State Code base code is cost-effective for residential buildings in all climate zones in New Hampshire.
2012-08-22
... State of New Hampshire. See 77 FR 11809. The NPR proposed approval of the New Hampshire State... Hampshire SIP revision, 77 FR 11809, for the visibility impact using the 20% worst natural visibility... Section D. Step 4.d (70 FR 39156, 39167, July 6, 2005). The utilization and parameters used in the...
Study of CNC Grinding Machining Method About Isometric Polygon Profile
无
2002-01-01
The formed principle and CNC grinding machining method of isometric polygonal profile are studied deeply and systematically. Equation about section curve of isometric polygon profile is set up by means of geometric principle. With the use of differential geometry theory, the curve is proved to be with geometric feature of convex curve. It is referred to as Isometric Polygonal Curve (IPC), because that is a kind of convex curve on which the distance between any parallel tangent lines is equal. Isometric Poly...
Preparation Of Control Space For Remeshing Of Polygonal Surfaces
Tomasz Jurczyk; Barbara Glut
2013-01-01
The subject of the article concerns the issues of remeshing, transforming a polygonal mesh into a triangular mesh adapted to surface. From the initial polygonal mesh the curvature of surface and boundary is retrieved and used to calculate a metric tensor varying in three-dimensional space. In the proposed approach the curvature is computed using local approximation of surfaces and curves on the basis of vertices of the polygonal mesh. An essential part of the presented remeshing procedure is...
New Hampshire Better Buildings - Final Report
Cramton, Karen [NH Office of Energy and Planning; Peters, Katherine
2014-11-01
With $10 million in funding from the U.S. Department of Energy's (DOE) Better Buildings Neighborhood Program, the NH Better Buildings program was established as an initiative that initially empowered the three “Beacon Communities” of Berlin, Nashua and Plymouth to achieve transformative energy savings and reductions in fossil fuel use and greenhouse gases through deep energy retrofits and complementary sustainable energy solutions. The program also enabled those Communities to provide leadership to other communities around the state as “beacons” of energy efficiency. The goal of the program was to reduce energy use by a minimum of 15% through energy efficiency upgrades in residential and commercial buildings in the communities. The program expanded statewide in April 2012 by issuing a competitive solicitation for additional commercial projects non-profit, and municipal energy efficiency projects from any community in the state, and a partnership with the state’s utility-run, ratepayer-funded residential Home Performance with ENERGY STAR® (HPwES) program. The NH Better Buildings program was administered by the New Hampshire Office of Energy and Planning (OEP) and managed by the NH Community Development Finance Authority (CDFA). The program started in July 2010 and the last projects funded with American Reinvestment and Recovery Act (ARRA) funds were completed in August 2013. The program will continue after the American Recovery and Reinvestment Act program period as a Revolving Loan Fund, enabling low-interest financing for deep energy retrofits into the future.
New Hampshire Better Buildings - Final Interim Report
Cramton, Karen [NH Office of Energy and Planning; Peters, Katherine
2014-02-20
With $10 million in funding from the U.S. Department of Energy's (DOE) Better Buildings Neighborhood Program, the NH Better Buildings program was established as an initiative that initially empowered the three “Beacon Communities” of Berlin, Nashua and Plymouth to achieve transformative energy savings and reductions in fossil fuel use and greenhouse gases through deep energy retrofits and complementary sustainable energy solutions. The program also enabled those Communities to provide leadership to other communities around the state as “beacons” of energy efficiency. The goal of the program was to reduce energy use by a minimum of 15% through energy efficiency upgrades in residential and commercial buildings in the communities. The program expanded statewide in April 2012 by issuing a competitive solicitation for additional commercial projects non-profit, and municipal energy efficiency projects from any community in the state, and a partnership with the state’s utility-run, ratepayer-funded residential Home Performance with ENERGY STAR® (HPwES) program. The NH Better Buildings program was administered by the New Hampshire Office of Energy and Planning (OEP) and managed by the NH Community Development Finance Authority (CDFA). The program started in July 2010 and the last projects funded with American Reinvestment and Recovery Act (ARRA) funds were completed in August 2013. The program will continue after the American Recovery and Reinvestment Act program period as a Revolving Loan Fund, enabling low-interest financing for deep energy retrofits into the future.
Natural convection in polygonal enclosures with inner circular cylinder
Habibis Saleh
2015-12-01
Full Text Available This study investigates the natural convection induced by a temperature difference between cold outer polygonal enclosure and hot inner circular cylinder. The governing equations are solved numerically using built-in finite element method of COMSOL. The governing parameters considered are the number of polygonal sides, aspect ratio, radiation parameter, and Rayleigh number. We found that the number of contra-rotative cells depended on polygonal shapes. The convection heat transfer becomes constant at L / D > 0 . 77 and the polygonal shapes are no longer sensitive to the Nusselt number profile.
Perceptions and Expected Immediate Reactions to Tornado Warning Polygons
Lindell, M. K.; Huang, S. K.; Wei, H. L.; Samuelson, C. D.
2015-12-01
To provide people with more specific information about tornado threats, the National Weather Service has replaced its county-wide warnings with smaller warning polygons that more specifically indicate the risk area. However, tornado warning polygons do not have a standardized definition regarding tornado strike probabilities (ps) so it is unclear how warning recipients interpret them. To better understand this issue, 155 participants responded to 15 hypothetical warning polygons. After viewing each polygon, they rated the likelihood of a tornado striking their location and the likelihood that they would take nine different response actions ranging from continuing normal activities to getting in a car and driving somewhere safer. The results showed participants inferred that the ps was highest at the polygon's centroid, lower just inside the edges of the polygon, still lower (but not zero) just outside the edges of the polygon, and lowest in locations beyond that. Moreover, higher ps values were associated with lower expectations of continuing normal activities and higher expectations of seeking information from social sources (but not environmental cues) and higher expectations of seeking shelter (but not evacuating in their cars). These results indicate that most people make some errors in their ps judgments but are likely to respond appropriately to the ps they infer from the warning polygons. Overall, the findings from this study and other research can help meteorologists to better understand how people interpret the uncertainty associated with warning polygons and, thus, improve tornado warning systems.
Constrained Geodesic Centers of a Simple Polygon
Oh, Eunjin; Son, Wanbin; Ahn, Hee-Kap
2016-01-01
For any two points in a simple polygon P, the geodesic distance between them is the length of the shortest path contained in P that connects them. A geodesic center of a set S of sites (points) with respect to P is a point in P that minimizes the geodesic distance to its farthest site. In many realistic facility location problems, however, the facilities are constrained to lie in feasible regions. In this paper, we show how to compute the geodesic centers constrained to a set of line segment...
Peijun Du (杜培军); Tao Fang (方涛); Hong Tang (唐宏); Pengfei Shi (施鹏飞)
2003-01-01
In this paper, two new similarity measure methods based on set theory were proposed. Firstly, similarity measure of two sets based on set theory and set operation was discussed. This principle was used to spectral vectors, and two approaches were proposed. The first method was to create a spectral polygon corresponding to spectral curve, and similarity of two spectral vectors can be replaced by that of two polygons. Area of spectral polygon was used as quantification function and some effective indexes for similarity and dissimilarity were computed. The second method was to transform the original spectral vector to encoding vector according to absorption or reflectance feature bands, and similarity measure was conducted to encoding vectors. It proved that the spectral polygon-based approach was effective and can be used to hyperspectral RS image retrieval.
a Distributed Polygon Retrieval Algorithm Using Mapreduce
Guo, Q.; Palanisamy, B.; Karimi, H. A.
2015-07-01
The burst of large-scale spatial terrain data due to the proliferation of data acquisition devices like 3D laser scanners poses challenges to spatial data analysis and computation. Among many spatial analyses and computations, polygon retrieval is a fundamental operation which is often performed under real-time constraints. However, existing sequential algorithms fail to meet this demand for larger sizes of terrain data. Motivated by the MapReduce programming model, a well-adopted large-scale parallel data processing technique, we present a MapReduce-based polygon retrieval algorithm designed with the objective of reducing the IO and CPU loads of spatial data processing. By indexing the data based on a quad-tree approach, a significant amount of unneeded data is filtered in the filtering stage and it reduces the IO overhead. The indexed data also facilitates querying the relationship between the terrain data and query area in shorter time. The results of the experiments performed in our Hadoop cluster demonstrate that our algorithm performs significantly better than the existing distributed algorithms.
A DISTRIBUTED POLYGON RETRIEVAL ALGORITHM USING MAPREDUCE
Q. Guo
2015-07-01
Full Text Available The burst of large-scale spatial terrain data due to the proliferation of data acquisition devices like 3D laser scanners poses challenges to spatial data analysis and computation. Among many spatial analyses and computations, polygon retrieval is a fundamental operation which is often performed under real-time constraints. However, existing sequential algorithms fail to meet this demand for larger sizes of terrain data. Motivated by the MapReduce programming model, a well-adopted large-scale parallel data processing technique, we present a MapReduce-based polygon retrieval algorithm designed with the objective of reducing the IO and CPU loads of spatial data processing. By indexing the data based on a quad-tree approach, a significant amount of unneeded data is filtered in the filtering stage and it reduces the IO overhead. The indexed data also facilitates querying the relationship between the terrain data and query area in shorter time. The results of the experiments performed in our Hadoop cluster demonstrate that our algorithm performs significantly better than the existing distributed algorithms.
J P Silva; Silvestre, A. J.
2006-01-01
We compare the magnetic field at the center of and the self-magnetic flux through a current-carrying circular loop, with those obtained for current-carrying polygons with the same perimeter. As the magnetic field diverges at the position of the wires, we compare the self-fluxes utilizing several regularization procedures. The calculation is best performed utilizing the vector potential, thus highlighting its usefulness in practical applications. Our analysis answers some of the intuition chal...
Full Text Available List Contact us BodyParts3D Polygon mesh data (Polygon reduction rate = 99% IS-A Tree) Data detail Data name... Polygon mesh data (Polygon reduction rate = 99% IS-A Tree) DOI 10.18908/lsdba.nbdc00837-007 Description of ...data contents BodyParts3D organ model data with the polygon reduction rate of 99%. The zip-compressed downlo... Policy | Contact Us Polygon mesh data (Polygon reduction rate = 99% IS-A Tree) - BodyParts3D | LSDB Archive ...
Full Text Available List Contact us BodyParts3D Polygon mesh data (Polygon reduction rate = 99% PART-OF Tree) Data detail Data n...ame Polygon mesh data (Polygon reduction rate = 99% PART-OF Tree) DOI 10.18908/lsdba.nbdc00837-008 Descripti...on of data contents BodyParts3D organ model data with the polygon reduction rate of 99%. The zip-compressed ...tabase Site Policy | Contact Us Polygon mesh data (Polygon reduction rate = 99% PART-OF Tree) - BodyParts3D | LSDB Archive ...
Inaccessibility-Inside Theorem for Point in Polygon
Sinha, Shriprakash
2010-01-01
The paper explores the ideology behind the concept of inside a simple or self intersecting polygon by presenting new definitions on Inaccessibility and Inside for a point S related to a polygon P. It further goes on to give a theoretical proof to establish a relation as to when a point is inaccessible and inside a polygon. The proposed analytical solution depicts a novel way of tackling the well known point in polygon problem by employing the properties of epigraphs and hypographs, explicitly. Contrary to the ambiguous solutions given by the cross over for the simple and self intersecting polygons and the solution of a point being multi-ply inside a self intersecting polygon given by the winding number rule, the current solution gives unambiguous and singular result for both kinds of polygons. The solution also deals with the rare and subtle issues of ray crossing a odd or even number of vertices, an edge as well as analytically questions the idea of a point being multi-ply inside a polygon. Finally, the curr...
The geometry of inner spanning trees for planar polygons
Ivanov, Alexandr O; Tuzhilin, Alexey A [P.G. Demidov Yaroslavl State University, Yaroslavl (Russian Federation)
2012-04-30
We study the geometry of minimal inner spanning trees for planar polygons (that is, spanning trees whose edge-intervals lie in these polygons). We construct analogues of Voronoi diagrams and Delaunay triangulations, prove that every minimal inner spanning tree is a subgraph of an appropriate Delaunay triangulation, and describe the possible structure of the cells of such triangulations.
Distributed algorithm for controlling scaled-free polygonal formations
Garcia de Marina Peinado, Hector; Jayawardhana, Bayu; Cao, Ming
2017-01-01
This paper presents a distributed algorithm for controlling the deployment of a team of agents in order to form a broad class of polygons, including regular ones, where each agent occupies a corner of the polygon. The algorithm shares the properties from the popular distance- based rigid formation c
EDGE REMOVAL OF 3D POLYGONAL MODEL USING MAYA API
SAMEER ARORA
2010-09-01
Full Text Available In various applications of computer graphics, 3D polygonal modeling is used, which consists millions of triangular polygon. In this polygon attributes – vertices, edges and faces’ details are to be stored. In order to control the processing time, storing space, and transfer speed, it is often required to reduce the information ofthese polygonal 3D models. In this paper an effort is made to reduce the number of edges. There are various methods to reduce faces and edges of these 3D models. A C++ dynamic link library as Maya Plugin has been created to remove number of edges of 3D triangular polygon model using the Quadric Error Metrics (QEM in MAYA v2010 x64 API. QEM allows fast and accurate geometric simplification of 3D models.
New Hampshire Lost Person Study, 1974-1979.
Rosinski, Jane L.
To improve outdoor safety in general and the Hunter Safety Program in particular, 879 reported search and rescue incidents involving lost outdoor recreationists conducted by the New Hampshire Fish and Game Department for 1974 to 1979 were studied. Data indicated that most incidents involved hikers (45%) and hunters (18%), occurred on clear sunny…
77 FR 74725 - New Hampshire Disaster #NH-00024
2012-12-17
... ADMINISTRATION New Hampshire Disaster NH-00024 AGENCY: U.S. Small Business Administration. ACTION: Notice... completed loan applications to: U.S. Small Business Administration, Processing and Disbursement Center... Disaster Assistance, U.S. Small Business Administration, 409 3rd Street SW., Suite 6050, Washington,...
78 FR 48764 - New Hampshire Disaster # NH-00026
2013-08-09
... ADMINISTRATION New Hampshire Disaster NH-00026 AGENCY: U.S. Small Business Administration. ACTION: Notice.../02/2014. ADDRESSES: Submit completed loan applications to: U.S. Small Business Administration... CONTACT: A. Escobar, Office of Disaster Assistance, U.S. Small Business Administration, 409 3rd Street...
76 FR 77578 - New Hampshire Disaster #NH-00022
2011-12-13
... ADMINISTRATION New Hampshire Disaster NH-00022 AGENCY: U.S. Small Business Administration. ACTION: Notice...: Submit completed loan applications to: U.S. Small Business Administration, Processing and Disbursement... of Disaster Assistance, U.S. Small Business Administration, 409 3rd Street SW., Suite...
The Constitutionality of School Choice in New Hampshire
Douglas, Charles G., III; Komer, Richard D.
2004-01-01
Does a "school choice" program, under which state funds are disbursed on a neutral basis to parents in the form of a voucher to defray the cost of sending their children to a school of their choice, run afoul of the Establishment Clause of the First Amendment to the United States Constitution, or of the New Hampshire Constitution? No. A…
Generating realistic roofs over a rectilinear polygon
Ahn, Heekap
2011-01-01
Given a simple rectilinear polygon P in the xy-plane, a roof over P is a terrain over P whose faces are supported by planes through edges of P that make a dihedral angle π/4 with the xy-plane. In this paper, we introduce realistic roofs by imposing a few additional constraints. We investigate the geometric and combinatorial properties of realistic roofs, and show a connection with the straight skeleton of P. We show that the maximum possible number of distinct realistic roofs over P is ( ⌊(n-4)/4⌋ (n-4)/2) when P has n vertices. We present an algorithm that enumerates a combinatorial representation of each such roof in O(1) time per roof without repetition, after O(n 4) preprocessing time. We also present an O(n 5)-time algorithm for computing a realistic roof with minimum height or volume. © 2011 Springer-Verlag.
Periodic billiard trajectories in polygons: generating mechanisms
Vorobets, Ya B.; Gal'perin, G. A.; Stepin, Anatolii M.
1992-06-01
CONTENTSIntroduction §1. Billiard trajectories in a plane domain §2. Fagnano's problem. Mechanical interpretations of periodic trajectories in triangles §3. An extremal property of billiard trajectories. Birkhoff's theorem. The non-existence of a unified construction of periodic trajectories in obtuse triangles §4. 'Perpendicular' trajectories in obtuse triangles of special shape §5. 'Perpendicular' trajectories in rational polygons and polyhedra §6. Stable trajectories §7. Stable perpendicular trajectories §8. Isolated trajectories §9. Isolated trajectories in acute and obtuse triangles. The bifurcation diagram of isolated trajectories (a 'hang-glider' configuration) §10. The density of F-triangles in a neighbourhood of (0, 0) §11. Generalization of the construction of isolated trajectories in obtuse triangles §12. Stable and unstable billiard trajectories in plane Weyl chambers §13. A criterion for the stability of periodic trajectories in a regular hexagonConclusionReferences
Diffusion-Limited Aggregation with Polygon Particles
邓礼; 王延颋; 欧阳钟灿
2012-01-01
Diffusion-limited aggregation (DLA) assumes that particles perform pure random walk at a finite tem- perature and aggregate when they come close enough and stick together. Although it is well known that DLA in two dimensions results in a ramified fractal structure, how the particle shape influences the formed morphology is still un- clear. In this work, we perform the off-lattice two-dimensional DLA simulations with different particle shapes of triangle, quadrangle, pentagon, hexagon, and octagon, respectively, and compare with the results for circular particles. Our results indicate that different particle shapes only change the local structure, but have no effects on the global structure of the formed fractal duster. The local compactness decreases as the number of polygon edges increases.
High speed printing with polygon scan heads
Stutz, Glenn
2016-03-01
To reduce and in many cases eliminate the costs associated with high volume printing of consumer and industrial products, this paper investigates and validates the use of the new generation of high speed pulse on demand (POD) lasers in concert with high speed (HS) polygon scan heads (PSH). Associated costs include consumables such as printing ink and nozzles, provisioning labor, maintenance and repair expense as well as reduction of printing lines due to high through put. Targets that are applicable and investigated include direct printing on plastics, printing on paper/cardboard as well as printing on labels. Market segments would include consumer products (CPG), medical and pharmaceutical products, universal ID (UID), and industrial products. In regards to the POD lasers employed, the wavelengths include UV(355nm), Green (532nm) and IR (1064nm) operating within the repetition range of 180 to 250 KHz.
Home health services in New Hampshire.
Hale, F A; Jacobs, A R
1976-01-01
While home health services have traditionally been an underused component of the health care system, current trends suggest the desirability of expanding these services. These trends include an increase in the number of elderly who need the benefits of home care, the recognition that long-term chronic illnesses require appropriate management at home, and concern that patients have access to care at the level most appropriate to their illnesses. In New Hampshire, 41 certified home health agencies offer services. Little systematic research has been conducted on the kinds of services they provide and the patients seen by their staffs. Patient encounter data were collected from a sample of eight agencies for a 4-week period. Staff of the agencies used the patient contact record developed by the National Functional Task Analysis Cooperative Study to collect data. The data reflected differences among the agencies in the size of the populations they serve, organizational characteristics, reasons for patients' visits, expected sources of the revenue that supported them, and the diagnosis of the patients they cared for. The agencies served areas with populations ranging from 1,000 to 40,000. The staffs ranged from 1 to 14 full-time persons. Two were public agencies; the others had voluntary sponsorship. When data on reasons for visits were averaged for the eight agencies, it was shown that 72% of the visits were made for disease control activities such as care for a chronic or acute condition or for treatment or a laboratory test. Disease prevention activities such as a checkup for adults, children, prenatal or postnatal care, or health education accounted for only 24% of the visits. This result may indicate that, in areas short of physician manpower, the community health nurse is taking on increasing responsibility for medical care as well as health and education. Reimbursement for the visits came from Medicare, 25%; Medicaid-welfare, 14%; the patients, 18%; and health
Wenrich, M. L.; Christensen, P. R.
The mechanism for the genesis of the polygonal terrains in Acidalia and Utopia Planitia has long been sought: however, no completely satisfying model was put forth that characterizes the evolution of these complexly patterned terrains. The polygons are roughly hexagonal but some are not entirely enclosed by fractures. These polygonal features range in widths from approximately 5 to 20 km. Several origins were proposed that describe the polygon borders as desiccation cracks, columnar jointing in a cooled lava, or frost-wedge features. These tension-induced cracking hypotheses were addressed by Pechmann, who convincingly disputes these mechanisms of formation based on scale magnitude difficulties and morphology. Pechmann suggests instead that the cracks delineating the 5-20-km-wide polygons on the northern plains of Mars are graben resulting from deep-seated, uniform, horizontal tension. The difficulty with this hypothesis is that no analogous polygonal forms are known to have originated by tectonism on Earth. McGill and Hills propose that the polygonal terrains on Mars resulted from either rapid desiccation of sediments or cooling of volcanics coupled with differential compaction of the material over a buried irregular topographic surface. They suggest that fracturing was enhanced over the areas of positive relief and was suppressed above the topographic lows. McGill and Hills suggest that the spacing of the topographic highs primarily controls the size of the Martian polygons and the physics of the shrinkage process is a secondary concern. Ray et. al. conducted a terrestrial study of patterned ground in periglacial areas of the U.S. to determine the process responsible for polygonal ground formation. They developed a model for polygon formation in which convection of seasonal melt water above a permafrost layer, driven by an unstable density stratification, differentially melts the permafrost interface, causing it to become undulatory.
Rectangular Blocks vs Polygonal Walls in Archaeoseismology
Klaus-G. Hinzen
2017-07-01
Full Text Available Collapsed or deformed walls in ancient structures constitute important evidence in archaeoseismology, where damage is interpreted in terms of earthquake ground motion. A large variety of wall types have been developed during the millennia in different cultural backgrounds. Often walls with polygonal-shaped building blocks are regarded as more earthquake-resistant than a wall consisting of rectangular elements and, as is sometimes speculated, that the irregular wall types were intentionally developed for that purpose. We use simply structured discrete element models of four walls with different block geometries, perfect rectangular, an Inka-type structure and two polygonal designs, to test their dynamic behavior. In addition to an analytic calculation of ground motion, we use measured strong motion signals as boundary conditions for the 3D wall models with varying height to width ratios. At peak ground accelerations between 1.0 and 9.0 m/s2 and major frequencies of 0.5 to 3 Hz, numeric experiments with the horizontally applied analytic ground motions result in clear differences in the resistance of the four wall types with the rectangular block wall being most vulnerable. For more complex measured 3D motions the Inka-type wall proves more stable than the rectangular block wall; however, height to width ratio still has equally strong influence on the stability. Internal deformation of non-collapsed walls shows some correlation with the parameters of the driving motion. For simple impulsive ground motions, a peak ground displacement threshold exists between toppling and remaining upright for all four models but peak acceleration cannot be reliably back calculated.
Vector modeling and track simulation in axial turn-milling motion
JIANG Zeng-hui; JIA Chun-de
2005-01-01
Through vector analysis the kinetic vector model is built in a machining cylinder surface through axial turn-milling. When building a kinetic vector model in the machining field, machining through axial turn-milling and using equilateral triangles and square prism surfaces, the kinetic vector model is given any equilateral polygon prismic surface. Kinetic tracks are simulated through these kinetic models respectively, thus it can be seen that the axial turn-milling is a very effective method in manufacturing any equilateral, polygon, prismic surface.
LaGory, K. E.; Walston, L. J.; Goulet, C; Van Lonkhuyzen, R. A.; Najjar, S.; Andrews, C.; Environmental Science Division; Univ. of New Hampshire; U.S. Air Force
2009-11-01
The decline of many snake populations is attributable to habitat loss, and knowledge of habitat use is critical to their conservation. Resource characteristics (e.g., relative availability of different habitat types, soils, and slopes) within a landscape are scale-dependent and may not be equal across multiple spatial scales. Thus, it is important to identify the relevant spatial scales at which resource selection occurs. We conducted a radiotelemetry study of eastern hognose snake (Heterodon platirhinos) home range size and resource use at different hierarchical spatial scales. We present the results for 8 snakes radiotracked during a 2-year study at New Boston Air Force Station (NBAFS) in southern New Hampshire, USA, where the species is listed by the state as endangered. Mean home range size (minimum convex polygon) at NBAFS (51.7 {+-} 14.7 ha) was similar to that reported in other parts of the species range. Radiotracked snakes exhibited different patterns of resource use at different spatial scales. At the landscape scale (selection of locations within the landscape), snakes overutilized old-field and forest edge habitats and underutilized forested habitats and wetlands relative to availability. At this scale, snakes also overutilized areas containing sandy loam soils and areas with lower slope (mean slope = 5.2% at snake locations vs. 6.7% at random locations). We failed to detect some of these patterns of resource use at the home range scale (i.e., within the home range). Our ability to detect resource selection by the snakes only at the landscape scale is likely the result of greater heterogeneity in macrohabitat features at the broader landscape scale. From a management perspective, future studies of habitat selection for rare species should include measurement of available habitat at spatial scales larger than the home range. We suggest that the maintenance of open early successional habitats as a component of forested landscapes will be critical for the
Conformal array design on arbitrary polygon surface with transformation optics
Li Deng
2016-06-01
Full Text Available A transformation-optics based method to design a conformal antenna array on an arbitrary polygon surface is proposed and demonstrated in this paper. This conformal antenna array can be adjusted to behave equivalently as a uniformly spaced linear array by applying an appropriate transformation medium. An typical example of general arbitrary polygon conformal arrays, not limited to circular array, is presented, verifying the proposed approach. In summary, the novel arbitrary polygon surface conformal array can be utilized in array synthesis and beam-forming, maintaining all benefits of linear array.
Interpolation Error Estimates for Mean Value Coordinates over Convex Polygons.
Rand, Alexander; Gillette, Andrew; Bajaj, Chandrajit
2013-08-01
In a similar fashion to estimates shown for Harmonic, Wachspress, and Sibson coordinates in [Gillette et al., AiCM, to appear], we prove interpolation error estimates for the mean value coordinates on convex polygons suitable for standard finite element analysis. Our analysis is based on providing a uniform bound on the gradient of the mean value functions for all convex polygons of diameter one satisfying certain simple geometric restrictions. This work makes rigorous an observed practical advantage of the mean value coordinates: unlike Wachspress coordinates, the gradient of the mean value coordinates does not become large as interior angles of the polygon approach π.
Quantum algorithmic integrability: The metaphor of classical polygonal billiards
Mantica, Giorgio
2000-06-01
We study the algorithmic complexity of motions in classical polygonal billiards, which, as the number of sides increases, tend to curved billiards, both regular and chaotic. This study unveils the equivalence of this problem to the procedure of quantization: the average complexity of symbolic trajectories in polygonal billiards features the same scaling relations (with respect to the number of sides) that govern quantum systems when a semiclassical parameter is varied. Two cases, the polygonal approximations of the circle and of the stadium, are examined in detail and are presented as paradigms of quantization of integrable and chaotic systems.
Conformal array design on arbitrary polygon surface with transformation optics
Deng, Li; Wu, Yongle; Hong, Weijun; Zhu, Jianfeng; Peng, Biao; Li, Shufang
2016-06-01
A transformation-optics based method to design a conformal antenna array on an arbitrary polygon surface is proposed and demonstrated in this paper. This conformal antenna array can be adjusted to behave equivalently as a uniformly spaced linear array by applying an appropriate transformation medium. An typical example of general arbitrary polygon conformal arrays, not limited to circular array, is presented, verifying the proposed approach. In summary, the novel arbitrary polygon surface conformal array can be utilized in array synthesis and beam-forming, maintaining all benefits of linear array.
Fixing Geometric Errors on Polygonal Models: A Survey
Tao Ju
2009-01-01
Polygonal models are popular representations of 3D objects. The use of polygonal models in computational applications often requires a model to properly bound a 3D solid. That is, the polygonal model needs to be closed, manifold, and free of self-intersections. This paper surveys a sizeable literature for repairing models that do not satisfy this criteria, focusing on categorizing them by their methodology and capability. We hope to offer pointers to further readings for researchers and practitioners, and suggestions of promising directions for future research endeavors.
North Slope, Alaska ESI: FISH (Fish Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and freshwater fish species for the North Slope of Alaska. Vector...
Alabama ESI: MGT (Management Area Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive human-use data for designated critical habitats, state parks, wildlife refuges, and wildlife management areas in Alabama. Vector...
Roche, John
1997-01-01
Suggests an approach to teaching vectors that promotes active learning through challenging questions addressed to the class, as opposed to subtle explanations. Promotes introducing vector graphics with concrete examples, beginning with an explanation of the displacement vector. Also discusses artificial vectors, vector algebra, and unit vectors.…
Spectral segmentation of polygonized images with normalized cuts
Matsekh, Anna [Los Alamos National Laboratory; Skurikhin, Alexei [Los Alamos National Laboratory; Rosten, Edward [UNIV OF CAMBRIDGE
2009-01-01
We analyze numerical behavior of the eigenvectors corresponding to the lowest eigenvalues of the generalized graph Laplacians arising in the Normalized Cuts formulations of the image segmentation problem on coarse polygonal grids.
Contour polygonal approximation using shortest path in networks
Backes, André Ricardo; Bruno, Odemir Martinez
2013-01-01
Contour polygonal approximation is a simplified representation of a contour by line segments, so that the main characteristics of the contour remain in a small number of line segments. This paper presents a novel method for polygonal approximation based on the Complex Networks theory. We convert each point of the contour into a vertex, so that we model a regular network. Then we transform this network into a Small-World Complex Network by applying some transformations over its edges. By analyzing of network properties, especially the geodesic path, we compute the polygonal approximation. The paper presents the main characteristics of the method, as well as its functionality. We evaluate the proposed method using benchmark contours, and compare its results with other polygonal approximation methods.
BSYCHAB -- Habitat polygons for the Big Sycamore reserve area
U.S. Geological Survey, Department of the Interior — Benthic habitat polygon coverages have been created for marine reserve locations surrounding the Santa Barbara Basin. Diver, ROV and submersible video transects,...
Forests and Forest Cover - Ozark National Forest Service Compartments (polygon)
NSGIC GIS Inventory (aka Ramona) — Ozark - St. Francis National Forests stand inventory data for vegetation, maintained in polygon format. Compartment is defined as a division of forest for purposes...
VT Biodiversity Project - Representative Landscapes in Vermont polygons
Vermont Center for Geographic Information — (Link to Metadata) This coverage represents the results of an analysis of landscape diversity in Vermont. Polygons in the dataset represent as much as possible (in a...
PNW River Reach Files -- 1:100k Waterbodies (polygons)
Pacific States Marine Fisheries Commission — This feature class includes the POLYGON waterbody features from the 2001 version of the PNW River Reach files Arc/INFO coverage. Separate, companion feature classes...
Region 9 NPL Sites (Superfund Sites 2013) Polygons
U.S. Environmental Protection Agency — NPL site POLYGON locations for the US EPA Region 9. NPL (National Priorities List) sites are hazardous waste sites that are eligible for extensive long-term cleanup...
Polygonal Homographic Orbits of the Curved n-Body Problem
Diacu, Florin
2010-01-01
In the 2-dimensional n-body problem in spaces of constant curvature, k nonzero, with n \\geq 3, we study polygonal homographic solutions. We first provide necessary and sufficient conditions for the existence of polygonal homographic orbits and then consider the case of regular polygons. We further use this criterion to show that, for any n \\geq 3, the regular n-gon is a polygonal homographic orbit if and only if all masses are equal. Then we prove the existence of relative equilib- ria of non-equal masses on the sphere of curvature k > 0 for n = 3 in the case of scalene triangles. Such triangular relative equilibria occur only along fixed geodesics and are generated from fixed points of the sphere. Finally, through a classification of the isosceles case, we prove that not any three masses can form a triangular relative equilibrium.
Generalizing Lifted Tensor-Product Wavelets to Irregular Polygonal Domains
Bertram, M.; Duchaineau, M.A.; Hamann, B.; Joy, K.I.
2002-04-11
We present a new construction approach for symmetric lifted B-spline wavelets on irregular polygonal control meshes defining two-manifold topologies. Polygonal control meshes are recursively refined by stationary subdivision rules and converge to piecewise polynomial limit surfaces. At every subdivision level, our wavelet transforms provide an efficient way to add geometric details that are expanded from wavelet coefficients. Both wavelet decomposition and reconstruction operations are based on local lifting steps and have linear-time complexity.
A new measure for the rectilinearity of polygons
Zunic, Jovisa; Rosin, Paul L.
2002-11-01
A polygon Pis said to be rectilinear if all interior angles of P belong to the set {π/2, 3π/2}. In this paper we establish the mapping R(P)=(π/(π-2x√2))⊗(maxα∈[0,2π] ((P1(P,α)/√2⊗P2(P))-((2√2)/π)) where P is an arbitrary polygon, P2(P) denotes the Euclidean perimeter of P, while P1(P,α) is the perimeter in the sense of l1 metrics of the polygon obtained by the rotation of P by angle α with the origin as the center of the applied rotation. It turns out that R(P) can be used as an estimate for the rectilinearity of P. Precisely, R(P) has the following desirable properties: - any polygon P has the estimated rectilinearity R(P) which is a number from [0,1]; - R(P)=1 if and only if P is a rectilinear polygon; - infp∈II R(P) = 0, where II denotes the set of all polygons - a polygon's rectilinearity measure is invariant under similarity transformations. The proposed rectilinearity measure can be an alternative for the recently described measure R1(P)1. Those rectilinearity measures are essentially different since there is no monotonic function f, such that f(R1(P))= R(P), that holds for all P ∈ II. A simple procedure for computing R(P) for a given polygon P is described as well.
Realistic roofs over a rectilinear polygon
Ahn, Heekap
2013-11-01
Given a simple rectilinear polygon P in the xy-plane, a roof over P is a terrain over P whose faces are supported by planes through edges of P that make a dihedral angle π/4 with the xy-plane. According to this definition, some roofs may have faces isolated from the boundary of P or even local minima, which are undesirable for several practical reasons. In this paper, we introduce realistic roofs by imposing a few additional constraints. We investigate the geometric and combinatorial properties of realistic roofs and show that the straight skeleton induces a realistic roof with maximum height and volume. We also show that the maximum possible number of distinct realistic roofs over P is ((n-4)(n-4)/4 /2⌋) when P has n vertices. We present an algorithm that enumerates a combinatorial representation of each such roof in O(1) time per roof without repetition, after O(n4) preprocessing time. We also present an O(n5)-time algorithm for computing a realistic roof with minimum height or volume. © 2013 Elsevier B.V.
Bifurcation of self-folded polygonal bilayers
Abdullah, Arif M.; Braun, Paul V.; Hsia, K. Jimmy
2017-09-01
Motivated by the self-assembly of natural systems, researchers have investigated the stimulus-responsive curving of thin-shell structures, which is also known as self-folding. Self-folding strategies not only offer possibilities to realize complicated shapes but also promise actuation at small length scales. Biaxial mismatch strain driven self-folding bilayers demonstrate bifurcation of equilibrium shapes (from quasi-axisymmetric doubly curved to approximately singly curved) during their stimulus-responsive morphing behavior. Being a structurally instable, bifurcation could be used to tune the self-folding behavior, and hence, a detailed understanding of this phenomenon is appealing from both fundamental and practical perspectives. In this work, we investigated the bifurcation behavior of self-folding bilayer polygons. For the mechanistic understanding, we developed finite element models of planar bilayers (consisting of a stimulus-responsive and a passive layer of material) that transform into 3D curved configurations. Our experiments with cross-linked Polydimethylsiloxane samples that change shapes in organic solvents confirmed our model predictions. Finally, we explored a design scheme to generate gripper-like architectures by avoiding the bifurcation of stimulus-responsive bilayers. Our research contributes to the broad field of self-assembly as the findings could motivate functional devices across multiple disciplines such as robotics, artificial muscles, therapeutic cargos, and reconfigurable biomedical devices.
Alliances of cooperation: negotiating New Hampshire nurse practitioners' prescribing practice.
Sampson, Deborah A
2009-01-01
Nurse practitioner legislation varies among states, particularly in relation to practice without physician oversight, altering the legal environment within which nurse practitioners can use knowledge and skills to meet patient needs. Using New Hampshire as a case study, this historical analysis of nurse practitioners' negotiations over time for independent practice, defined in state practice acts, illuminates the complex social and economic factors affecting nurses' struggle to gain legal rights over their own professional practice without supervision and intervention from another profession. In New Hampshire, not only did organized medicine oppose nurses rights to practice, but pharmacists demanded the right to control all aspects of medication management, including who could prescribe and under what circumstances prescribing could occur. Shifting social and political terrain as well as changes in legislative and state professional board leadership affected the environment and negotiations of a small group of nurses who were ultimately successful in obtaining the right to define their own professional practice.
Image segmentation by hierarchial agglomeration of polygons using ecological statistics
Prasad, Lakshman; Swaminarayan, Sriram
2013-04-23
A method for rapid hierarchical image segmentation based on perceptually driven contour completion and scene statistics is disclosed. The method begins with an initial fine-scale segmentation of an image, such as obtained by perceptual completion of partial contours into polygonal regions using region-contour correspondences established by Delaunay triangulation of edge pixels as implemented in VISTA. The resulting polygons are analyzed with respect to their size and color/intensity distributions and the structural properties of their boundaries. Statistical estimates of granularity of size, similarity of color, texture, and saliency of intervening boundaries are computed and formulated into logical (Boolean) predicates. The combined satisfiability of these Boolean predicates by a pair of adjacent polygons at a given segmentation level qualifies them for merging into a larger polygon representing a coarser, larger-scale feature of the pixel image and collectively obtains the next level of polygonal segments in a hierarchy of fine-to-coarse segmentations. The iterative application of this process precipitates textured regions as polygons with highly convolved boundaries and helps distinguish them from objects which typically have more regular boundaries. The method yields a multiscale decomposition of an image into constituent features that enjoy a hierarchical relationship with features at finer and coarser scales. This provides a traversable graph structure from which feature content and context in terms of other features can be derived, aiding in automated image understanding tasks. The method disclosed is highly efficient and can be used to decompose and analyze large images.
Revegetation at Two Construction Sites in New Hampshire and Alaska,
1980-01-01
nutrients , or maize seedlings was adversely affected when maintaining soil moisture. The cost effectiveness soils contained a high concentration of gravels...New Hampshire, and Fairbanks, Alaska. During three growing seasons, we studied the applicability and I. cost effectiveness of various nutrient sources...and mulch materials. The nutrient sources included sewage sludge (at 40, 60 and S0 tons/acre) and commercial fertilizer (at 200, 400 and 600 lb/acre
The reference phantoms: voxel vs polygon.
Kim, C H; Yeom, Y S; Nguyen, T T; Wang, Z J; Kim, H S; Han, M C; Lee, J K; Zankl, M; Petoussi-Henss, N; Bolch, W E; Lee, C; Chung, B S
2016-06-01
The International Commission on Radiological Protection (ICRP) reference male and female adult phantoms, described in Publication 110, are voxel phantoms based on whole-body computed tomography scans of a male and a female patient, respectively. The voxel in-plane resolution and the slice thickness, of the order of a few millimetres, are insufficient for proper segmentation of smaller tissues such as the lens of the eye, the skin, and the walls of some organs. The calculated doses for these tissues therefore present some limitations, particularly for weakly penetrating radiation. Similarly, the Publication 110 phantoms cannot represent 8-40-µm-thick target regions in respiratory or alimentary tract organs. Separate stylised models have been used to represent these tissues for calculation of the ICRP reference dose coefficients (DCs). ICRP Committee 2 recently initiated a research project, the ultimate goal of which is to convert the Publication 110 phantoms to a high-quality polygon-mesh (PM) format, including all source and target regions, even those of the 8-40-µm-thick alimentary and respiratory tract organs. It is expected that the converted phantoms would lead to the same or very similar DCs as the Publication 110 reference phantoms for penetrating radiation and, at the same time, provide more accurate DCs for weakly penetrating radiation and small tissues. Additionally, the reference phantoms in the PM format would be easily deformable and, as such, could serve as a starting point to create phantoms of various postures for use, for example, in accidental dose calculations. This paper will discuss the current progress of the phantom conversion project and its significance for ICRP DC calculations.
Free Marketeers, Policy Wonks, and Yankee Democracy: School Vouchers in New Hampshire, 1973-1976
Carl, Jim
2008-01-01
In this article, Jim Carl uses archival sources and interviews to chronicle the effort to bring school vouchers to New Hampshire. In 1973, the New Hampshire Department of Education initiated a plan, funded by the U.S. Office of Economic Opportunity, to institute vouchers in a handful of school districts. Though the initiative had the support of…
Marion, Scott F.; Vander Els, Jonathan; Leather, Paul
2017-01-01
In New Hampshire, a new performance assessment system focuses on reciprocal accountability and shared leadership among teachers and leaders at the school, district, and state levels. This concept of reciprocal accountability, developed by school improvement expert Richard Elmore, is at the core of New Hampshire's Performance Assessment of…
75 FR 53268 - Adequacy of New Hampshire Municipal Solid Waste Landfill Permit Program
2010-08-31
... AGENCY 40 CFR Parts 239 and 258 Adequacy of New Hampshire Municipal Solid Waste Landfill Permit Program... approve New Hampshire's modification of its approved Municipal Solid Waste Landfill Program. On March 22... be issued to certain municipal solid waste landfills by approved states. On June 28, 2010...
78 FR 14319 - New Hampshire; Amendment No. 1 to Notice of a Major Disaster Declaration
2013-03-05
..., Disaster Unemployment Assistance (DUA); 97.046, Fire Management Assistance Grant; 97.048, Disaster Housing... SECURITY Federal Emergency Management Agency New Hampshire; Amendment No. 1 to Notice of a Major Disaster... notice of a major disaster declaration for the State of New Hampshire (FEMA-4095-DR), dated November...
The Bottom Line: Kids Count to New Hampshire's Future. A Special Report.
Gittel, Ross; Gottlob, Brian
The sixth Kids Count publication from New Hampshire, this report departs from past work in that, in addition to updating state data on child health and well-being, it looks at that information in relation to data on the New Hampshire economy. Through detailed statistical analysis, the report explains how the status of children in New Hampshire…
Finding largest small polygons with GloptiPoly
Henrion, Didier
2011-01-01
A small polygon is a convex polygon of unit diameter. We are interested in small polygons which have the largest area for a given number of vertices $n$. Many instances are already solved in the literature, namely for all odd $n$, and for $n=4, 6$ and 8. Thus, for even $n\\geq 10$, instances of this problem remain open. Finding those largest small polygons can be formulated as nonconvex quadratic programming problems which can challenge state-of-the-art global optimization algorithms. We show that a recently developed technique for global polynomial optimization, based on a semidefinite programming approach to the generalized problem of moments and implemented in the public-domain Matlab package GloptiPoly, can successfully find largest small polygons for $n=10$ and $n=12$. Therefore this significantly improves existing results in the domain. When coupled with accurate convex conic solvers, GloptiPoly can provide numerical guarantees of global optimality, as well as rigorous guarantees relying on interval arit...
A QUALITY ASSESSMENT METHOD FOR 3D ROAD POLYGON OBJECTS
L. Gao
2015-08-01
Full Text Available With the development of the economy, the fast and accurate extraction of the city road is significant for GIS data collection and update, remote sensing images interpretation, mapping and spatial database updating etc. 3D GIS has attracted more and more attentions from academics, industries and governments with the increase of requirements for interoperability and integration of different sources of data. The quality of 3D geographic objects is very important for spatial analysis and decision-making. This paper presents a method for the quality assessment of the 3D road polygon objects which is created by integrating 2D Road Polygon data with LiDAR point cloud and other height information such as Spot Height data in Hong Kong Island. The quality of the created 3D road polygon data set is evaluated by the vertical accuracy, geometric and attribute accuracy, connectivity error, undulation error and completeness error and the final results are presented.
Vibration induced flow in hoppers: DEM 2D polygon model
无
2008-01-01
A two-dimensional discrete element model (DEM) simulation of cohesive polygonal particles has been developed to assess the benefit of point source vibration to induce flow in wedge-shaped hoppers. The particle-particle interaction model used is based on a multi-contact principle.The first part of the study investigated particle discharge under gravity without vibration to determine the critical orifice size (Be) to just sustain flow as a function of particle shape. It is shown that polygonal-shaped particles need a larger orifice than circular particles. It is also shown that Be decreases as the number of particle vertices increases. Addition of circular particles promotes flow of polygons in a linear manner.The second part of the study showed that vibration could enhance flow, effectively reducing Be. The model demonstrated the importance of vibrator location (height), consistent with previous continuum model results, and vibration amplitude in enhancing flow.
Preparation Of Control Space For Remeshing Of Polygonal Surfaces
Tomasz Jurczyk
2013-01-01
Full Text Available The subject of the article concerns the issues of remeshing, transforming a polygonal mesh into a triangular mesh adapted to surface. From the initial polygonal mesh the curvature of surface and boundary is retrieved and used to calculate a metric tensor varying in three-dimensional space. In the proposed approach the curvature is computed using local approximation of surfaces and curves on the basis of vertices of the polygonal mesh. An essential part of the presented remeshing procedure is creation of a control space structure based on the retrieved discrete data. The subsequent process of remeshing is then supervised by the contents of this auxiliary structure. The article presents various aspects related to the procedure of initialization, creation and adjusting the control space structure.
Measured Two-Dimensional Ice-Wedge Polygon Thermal Dynamics
Cable, William; Romanovsky, Vladimir; Busey, Robert
2016-04-01
Ice-wedge polygons are perhaps the most dominant permafrost related features in the arctic landscape. The microtopography of these features, that includes rims, troughs, and high and low polygon centers, alters the local hydrology, as water tends to collect in the low areas. During winter, wind redistribution of snow leads to an increased snowpack depth in the low areas, while the slightly higher areas often have very thin snow cover, leading to differences across the landscape in vegetation communities and soil moisture between higher and lower areas. These differences in local surface conditions lead to spatial variability of the ground thermal regime in the different microtopographic areas and between different types of ice-wedge polygons. To study these features in depth, we established temperature transects across four different types of ice-wedge polygons near Barrow, Alaska. The transects were composed of five vertical array thermistor probes (VATP) beginning in the center of each polygon and extending through the trough to the rim of the adjacent polygon. Each VATP had 16 thermistors from the surface to a depth of 1.5 m. In addition to these 80 subsurface temperature measurement points per polygon, soil moisture, thermal conductivity, heat flux, and snow depth were all measured in multiple locations for each polygon. Above ground, a full suite of micrometeorological instrumentation was present at each polygon. Data from these sites has been collected continuously for the last three years. We found snow cover, timing and depth, and active layer soil moisture to be major controlling factors in the observed thermal regimes. In troughs and in the centers of low-center polygons, the combined effect of typically saturated soils and increased snow accumulation resulted in the highest mean annual ground temperatures (MAGT). Additionally, these areas were the last part of the polygon to refreeze during the winter. However, increased active layer thickness was not
The finite cell method for polygonal meshes: poly-FCM
Duczek, Sascha; Gabbert, Ulrich
2016-10-01
In the current article, we extend the two-dimensional version of the finite cell method (FCM), which has so far only been used for structured quadrilateral meshes, to unstructured polygonal discretizations. Therefore, the adaptive quadtree-based numerical integration technique is reformulated and the notion of generalized barycentric coordinates is introduced. We show that the resulting polygonal (poly-)FCM approach retains the optimal rates of convergence if and only if the geometry of the structure is adequately resolved. The main advantage of the proposed method is that it inherits the ability of polygonal finite elements for local mesh refinement and for the construction of transition elements (e.g. conforming quadtree meshes without hanging nodes). These properties along with the performance of the poly-FCM are illustrated by means of several benchmark problems for both static and dynamic cases.
Silva, J. P.; Silvestre, A. J.
2005-09-01
We compare the magnetic field at the centre and the self-magnetic flux through a current-carrying circular loop, with those obtained for current-carrying polygons with the same perimeter. As the magnetic field diverges at the position of the wires, we compare the self-fluxes utilizing several regularization procedures. The calculation is best performed utilizing the vector potential, thus highlighting its usefulness in practical applications. Our analysis answers some of the intuition challenges students face when they encounter a related simple textbook example. These results can be applied directly to the determination of mutual inductances in a variety of situations.
Timing of the Acadian Orogeny in Northern New Hampshire.
Eusden Jr; Guzofski; Robinson; Tucker
2000-03-01
New U-Pb geochronology constrains the timing of the Acadian orogeny in the Central Maine Terrane of northern New Hampshire. Sixteen fractions of one to six grains each of zircon or monazite have been analyzed from six samples: (1) an early syntectonic diorite that records the onset of the Acadian; (2) a schist, a migmatite, and two granites that together record the peak of the Acadian; and (3) a postkinematic pluton that records the end of the Acadian. Zircon from the syntectonic Wamsutta Diorite gives a 207Pb/206Pb age of circa 408 Ma, the time at which the boundary between the deforming orogenic wedge and the foreland basin was in the vicinity of the Presidential Range. This age agrees well with the Emsian position of the northwest migrating Acadian orogenic front and records the beginning of the Acadian in this part of the Central Maine Terrane. We propose a possible Acadian tectonic model that incorporates the geochronologic, structural, and stratigraphic data. Monazite from the schist, migmatite, Bigelow Lawn Granite, and Slide Peak Granite gives 207Pb/206U ages, suggesting the peak of Acadian metamorphism and intrusion of two-mica granites occurred at circa 402-405 Ma, the main pulse of Acadian orogenesis. Previously reported monazite ages from schists that likely record the peak metamorphism in the Central Maine Terrane of New Hampshire and western Maine range from circa 406-384 Ma, with younger ages in southeastern New Hampshire and progressively older ages to the west, north, and northeast. Acadian orogenesis in the Presidential Range had ended by circa 355 Ma, the 207Pb/235U age of monazite from the Peabody River Granite. From 408 to perhaps at least 394 Ma, Acadian orogenesis in the Presidential Range was typical of the tectonic style, dominated by synkinematic metamorphism, seen in central and southern New Hampshire, Massachusetts, and Connecticut. From no earlier than 394 Ma to as late as 355 Ma, the orogenesis was typical of the style in parts of
Endoparasites of plethodontid salamanders from Paradise Brook, New Hampshire.
Muzzall, P M; Peebles, C R; Burton, T M
1997-12-01
Totals of 52 dusky salamanders Desmognathus fuscus, 51 two-lined salamanders Eurycea bislineata, 54 red-backed salamanders Plethodon cinereus, and 3 spring salamanders Gyrinophilus porphyriticus (Plethodontidae) collected in June and August 1995 from Paradise Brook, a tributary to Hubbard Brook, New Hampshire, were examined for parasites. Parasites found were Brachycoelium storeriae, Brachycoelium sp., Bothriocephalus rarus, Falcaustra sp., Omeia sp., Batracholandros magnavulvaris, and Cepedietta michiganensis. Eighty-six percent of the red-backed salamanders, a terrestrial species, harbored 1 or more parasites. Among the aquatic and semiaquatic species, 27% of the dusky and 45% of the two-lined salamanders were infected with 1 or more parasites.
United States National Grid for New Mexico, UTM 13, (1000m X 1000m polygons )
Earth Data Analysis Center, University of New Mexico — This is a polygon feature data layer of United States National Grid (1000m x 1000m polygons ) constructed by the Center for Interdisciplinary Geospatial Information...
U.S. Geological Survey, Department of the Interior — Shorelines Extracted from 1984-2015 Landsat Imagery: Petit Bois Island, Mississippi (Polygon: Combined Dates) is a polygon shapefile representing shorelines...
U.S. Geological Survey, Department of the Interior — Shorelines Extracted from 1984-2015 Landsat Imagery: Cat Island, Mississippi (Polygon: Combined Dates) is a polygon shapefile representing shorelines generated from...
U.S. Geological Survey, Department of the Interior — Shorelines Extracted from 1984-2015 Landsat Imagery: Ship Island, Mississippi (Polygon: Combined Dates) is a polygon shapefile representing shorelines generated from...
U.S. Geological Survey, Department of the Interior — Shorelines Extracted from 1984-2015 Landsat Imagery: Horn Island, Mississippi (Polygon: Combined Dates) is a polygon shapefile representing shorelines generated from...
U.S. Geological Survey, Department of the Interior — Shorelines Extracted from 1984-2015 Landsat Imagery: Petit Bois Island, Mississippi (Polygon: Individual Dates) is a dataset consisting of 271 polygon shapefiles...
U.S. Geological Survey, Department of the Interior — Shorelines Extracted from 1984-2015 Landsat Imagery: Horn Island, Mississippi (Polygon: Individual Dates) is a dataset consisting of 254 polygon shapefiles...
U.S. Geological Survey, Department of the Interior — Shorelines Extracted from 1984-2015 Landsat Imagery: Cat Island, Mississippi (Polygon: Individual Dates) is a dataset consisting of 268 polygon shapefiles...
United States National Grid for New Mexico, UTM 12, (1000m X 1000m polygons )
Earth Data Analysis Center, University of New Mexico — This is a polygon feature data layer of United States National Grid (1000m x 1000m polygons ) constructed by the Center for Interdisciplinary Geospatial Information...
U.S. Geological Survey, Department of the Interior — Shorelines Extracted from 1984-2015 Landsat Imagery: Petit Bois Island, Mississippi (Polygon: Combined Dates) is a polygon shapefile representing shorelines...
U.S. Geological Survey, Department of the Interior — Shorelines Extracted from 1984-2015 Landsat Imagery: Dauphin Island, Alabama (Polygon: Combined Dates) is a polygon shapefile representing shorelines generated from...
U.S. Geological Survey, Department of the Interior — Shorelines Extracted from 1984-2015 Landsat Imagery: Petit Bois Island, Mississippi (Polygon: Individual Dates) is a dataset consisting of 271 polygon shapefiles...
U.S. Geological Survey, Department of the Interior — Shorelines Extracted from 1984-2015 Landsat Imagery: Horn Island, Mississippi (Polygon: Individual Dates) is a dataset consisting of 254 polygon shapefiles...
U.S. Geological Survey, Department of the Interior — Shorelines Extracted from 1984-2015 Landsat Imagery: Horn Island, Mississippi (Polygon: Combined Dates) is a polygon shapefile representing shorelines generated from...
U.S. Geological Survey, Department of the Interior — Shorelines Extracted from 1984-2015 Landsat Imagery: Ship Island, Mississippi (Polygon: Combined Dates) is a polygon shapefile representing shorelines generated from...
U.S. Geological Survey, Department of the Interior — Shorelines Extracted from 1984-2015 Landsat Imagery: Cat Island, Mississippi (Polygon: Individual Dates) is a dataset consisting of 268 polygon shapefiles...
U.S. Geological Survey, Department of the Interior — Shorelines Extracted from 1984-2015 Landsat Imagery: Dauphin Island, Alabama (Polygon: Individual Dates) is a dataset consisting of 223 polygon shapefiles...
U.S. Geological Survey, Department of the Interior — Shorelines Extracted from 1984-2015 Landsat Imagery: Dauphin Island, Alabama (Polygon: Individual Dates) is a dataset consisting of 223 polygon shapefiles...
U.S. Geological Survey, Department of the Interior — Shorelines Extracted from 1984-2015 Landsat Imagery: Dauphin Island, Alabama (Polygon: Combined Dates) is a polygon shapefile representing shorelines generated from...
U.S. Geological Survey, Department of the Interior — Shorelines Extracted from 1984-2015 Landsat Imagery: Ship Island, Mississippi (Polygon: Individual Dates) is a dataset consisting of 280 polygon shapefiles...
Institutionalizing the option of dam removal: the New Hampshire initiative.
Lindloff, S D
2003-01-01
For two years, the State of New Hampshire has worked to institutionalize the option of dam removal. The high gradient streams that flow through the granite hills and mountains of this small northeastern state provided ideal conditions for dam construction, particularly during America's Industrial Revolution of the 1800s when mills were constructed throughout the area. With more than 4,800 dams in the state's database, there are many opportunities for the removal of dams that no longer serve a useful purpose, have become a public safety hazard and impact the river environment. Efforts to facilitate removal of dams in New Hampshire include the formation of a River Restoration Task Force and the creation of a dam removal program within the state agency responsible for regulating dams. This has led to the removal of two dams in the past year, with approximately ten additional projects in various stages of planning. A history of this agency-led initiative, as well as a discussion of the program's strengths, challenges and goals for the future are presented.
Hoffmann, Banesh
1975-01-01
From his unusual beginning in ""Defining a vector"" to his final comments on ""What then is a vector?"" author Banesh Hoffmann has written a book that is provocative and unconventional. In his emphasis on the unresolved issue of defining a vector, Hoffmann mixes pure and applied mathematics without using calculus. The result is a treatment that can serve as a supplement and corrective to textbooks, as well as collateral reading in all courses that deal with vectors. Major topics include vectors and the parallelogram law; algebraic notation and basic ideas; vector algebra; scalars and scalar p
Newell, Homer E
2006-01-01
When employed with skill and understanding, vector analysis can be a practical and powerful tool. This text develops the algebra and calculus of vectors in a manner useful to physicists and engineers. Numerous exercises (with answers) not only provide practice in manipulation but also help establish students' physical and geometric intuition in regard to vectors and vector concepts.Part I, the basic portion of the text, consists of a thorough treatment of vector algebra and the vector calculus. Part II presents the illustrative matter, demonstrating applications to kinematics, mechanics, and e
The Use of GIS Software to Deselect Forest Polygons by Their Location Relative to Linear Objects
S. K. Farber
2014-04-01
Full Text Available Polygon layers obtained on the basis of the DEM, may have specific characteristics, such as the emergence of geographically disparate polygons with the same identification number. The paper discusses the experience of spatial analysis such polygon layers, namely the experience of forest parcels adjacent to the parts of a hydrological network, using Arc Map 9.3.1. GIS software.
Pattern classification approaches to matching building polygons at multiple scales
Zhang, X; Zhao, X.; Molenaar, M.; Stoter, J.; Kraak M-J.; Ai, T.
2012-01-01
Matching of building polygons with different levels of detail is crucial in the maintenance and quality assessment of multi-representation databases. Two general problems need to be addressed in the matching process: (1) Which criteria are suitable? (2) How to effectively combine different criteria
Polygons, Pillars and Pavilions: Discovering Connections between Geometry and Architecture
Madden, Sean Patrick
2017-01-01
Crowning the second semester of geometry, taught within a Catholic middle school, the author's students explored connections between the geometry of regular polygons and architecture of local buildings. They went on to explore how these principles apply famous buildings around the world such as the monuments of Washington, D.C. and the elliptical…
Fat Polygonal Partitions with Applications to Visualization and Embeddings
de Berg, Mark; Sidiropoulos, Anastasios
2010-01-01
Let T be a rooted and weighted tree, where the weight of any node is equal to the sum of the weights of its children. The popular Treemap algorithm visualizes such a tree as a hierarchical partition of a square into rectangles, where the area of the rectangle corresponding to any node in T is equal to the weight of that node. The aspect ratio of the rectangles in such a rectangular partition necessarily depends on the weights and can become arbitrarily high. We introduce a new hierarchical partition scheme, called a polygonal partition, which uses convex polygons rather than just rectangles. We present two methods for constructing polygonal partitions, both having guarantees on the worst-case aspect ratio of the constructed polygons; in particular, both methods guarantee a bound on the aspect ratio that is independent of the weights of the nodes. We also consider rectangular partitions with slack, where the areas of the rectangles may differ slightly from the weights of the corresponding nodes. We show that t...
Micron-scale pattern formation in prestressed polygonal films
Annabattula, R. K.; Onck, P. R.
2011-01-01
In this paper we explore the spontaneous formation of micropatterns in thin prestressed polygonal films using finite element simulations. We study films with different size, thickness, and shape, including square, rectangular, pentagonal, and hexagonal films. Patterns form when the films release the
Pattern classification approaches to matching building polygons at multiple scales
Zhang, X; Zhao, X.; Molenaar, M.; Stoter, J.; Kraak M-J.; Ai, T.
2012-01-01
Matching of building polygons with different levels of detail is crucial in the maintenance and quality assessment of multi-representation databases. Two general problems need to be addressed in the matching process: (1) Which criteria are suitable? (2) How to effectively combine different criteria
Sub-wavelength resonances in polygonal metamaterial cylinders
Arslanagic, Samel; Breinbjerg, Olav
2008-01-01
It has been shown that the sub-wavelength resonances of circular MTM cylinders also occur for polygonal MTM cylinders. This is the case for lossless and non-dispersive cylinders as well as lossy and dispersive cylinders. The sub-wavelength resonances are thus not limited to structures of canonical...
Exact Potts/Tutte polynomials for polygon chain graphs
Shrock, Robert
2011-04-01
We present exact calculations of Potts model partition functions and the equivalent Tutte polynomials for polygon chain graphs with open and cyclic boundary conditions. Special cases of the results that yield flow and reliability polynomials are discussed. We also analyze special cases of the Tutte polynomials that determine various quantities of graph-theoretic interest.
Searching a Polygonal Region by a Boundary Searcher
Xue-Hou Tan
2009-01-01
This paper considers the problem of planning the motion of a searcher in a polygonal region to eventually "see" an intruder that is unpredictable and capable of moving arbitrarily fast. A searcher is called the boundary searcher if he continuously moves on the polygon boundary and can see only along the rays of the flashlights he holds at a time.We present necessary and sufficient conditions for an n-sided polygon to be searchable by a boundary searcher. Based on our characterization, the equivalence of the ability of the searchers having only one flashlight and the one of the searchers having full 360° vision is simply established, and moreover, an optimal O(n) time and space algorithm for determining the searchability of simple polygons is obtained. We also give an O(n log n + I) time algorithm for generating a search schedule if it exists, where I (< 3n2) is the number of search instructions reported. Our results improve upon the previously known O(n2) time and space bounds.
Determination of wave direction from linear and polygonal arrays
Fernandes, A.A.; Gouveia, A.D.; Nagarajan, R.
documentation of Borgman (1974) in case of linear arrays; and the second issue being the failure of Esteva (1976, 1977) to correctly determine wave directions over the design range 25 to 7 sec of his polygonal array. This paper presents requisite documentation...
Polygon formation and surface flow on a rotating fluid surface
Bergmann, Raymond; Tophøj, Laust Emil Hjerrild; Homan, T. A. M.;
2011-01-01
We present a study of polygons forming on the free surface of a water flow confined to a stationary cylinder and driven by a rotating bottom plate as described by Jansson et al. (Phys. Rev. Lett., vol. 96, 2006, 174502). In particular, we study the case of a triangular structure, either completel...
Computing a Canonical Polygonal Schema of an Orientable Triangulated Surface
Lazarus, Francis; Pocchiola, Michel; Vegter, Gert; Verroust, Anne
2001-01-01
A closed orientable surface of genus g can be obtained by appropriate identification of pairs of edges of a 4g-gon (the polygonal schema). The identified edges form 2g loops on the surface, that are disjoint except for their common end-point. These loops are generators of both the fundamental group
Wolstenholme, E Œ
1978-01-01
Elementary Vectors, Third Edition serves as an introductory course in vector analysis and is intended to present the theoretical and application aspects of vectors. The book covers topics that rigorously explain and provide definitions, principles, equations, and methods in vector analysis. Applications of vector methods to simple kinematical and dynamical problems; central forces and orbits; and solutions to geometrical problems are discussed as well. This edition of the text also provides an appendix, intended for students, which the author hopes to bridge the gap between theory and appl
On Polygons Admitting a Simson Line as Discrete Analogs of Parabolas
Tsukerman, Emmanuel
2012-01-01
We begin by proving a few general facts about Simson polygons, defined as polygons which admit a pedal line. We use an inductive argument to show that no convex $n$-gon, $n\\geq5$, admits a Simson Line. We then determine a property which characterizes Simson $n$-gons and show that one can be constructed for every $n\\geq3$. We proceed to show that a parabola can be viewed as a limit of special Simson polygons, called equidistant Simson polygons, and that these polygons provide the best piecewise linear continuous approximation to the parabola. Finally, we show that equidistant Simson polygons can be viewed as discrete analogs of parabolas and that they satisfy a number of results analogous to the pedal property, optical property, properties of Archimedes triangles and Lambert's Theorem of parabolas. The corresponding results for parabolas are easily obtained by applying a limit process to the equidistant Simson polygons.
Sediment Data from Great Bay Estuary, New Hampshire (ARMSTRONG74 shapefile)
U.S. Geological Survey, Department of the Interior — The sediment data presented in this data layer were from a geochemical study sited in Great Bay Estuary, New Hampshire. The analog data were originally converted...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) data for the New Hampshire coast from 2003 to 2004. ESI data characterize estuarine environments...
An assessment of mercury in waters, sediments and biota of Vermont and New Hampshire lakes [Draft
US Fish and Wildlife Service, Department of the Interior — The present report summarizes findings of a three-year field study of mercury in freshwater lakes of Vermont and New Hampshire. The study was undertaken jointly by...
Assessing the potential impacts of methylmercury on the common loon in southern New Hampshire
US Fish and Wildlife Service, Department of the Interior — The atmospheric deposition of mercury on New Hampshire's landscape impacts wildlife. The information presented in this report describes impacts on the Common Loon...
Social Vulnerability Index (SoVI) for New Hampshire based on 2000 Census Block Groups
National Oceanic and Atmospheric Administration, Department of Commerce — This data depicts the social vulnerability of New Hampshire census block groups to environmental hazards. Data were culled primarily from the 2000 Decennial Census.
Stone Polygons: Self-Organization Assisted by Noise
Fang, M.; Hager, B. H.
2002-12-01
Polygonal patterns formed by sorted gravel are commonly found on flat surfaces where water drainage is poor because of underlying permafrost. The similarity in pattern of these stone polygons with Rayleigh-Benard thermal convection cells is intriguing. There is even a suggestion that stone polygons are formed by Rayleigh-Benard convection of water through the underlying porous soil (Kranz et al, 1983). Recent developments in understanding the microphysical mechanisms of frost heaving (e.g. Wettlaufer, 1999; Zhu et al 2000) reinforce the conventional view that the freeze-thawing cycle of ice is the primary natural agent for this pattern formation. Mathematically, a large body of solutions to problems in pattern formation can be attributed to the reaction-diffusion system. There is a subtle difference, however, between systems like Rayleigh-Benard convection cells and stone polygons: The latter are formed in a noisy natural environment, the former in a highly controlled laboratory environment. In other words, the effects of large sources of noise must be accounted for explicitly in understanding the pattern formation of stone polygons. A distribution of stone polygons formed cooperatively results from sorting among water, soil, and stones controlled by weather changes. We propose a nonlinear reaction-diffusion type of model for this coupled process. We consider the incremental population density of stones (positive or negative relative to the initial uniform distribution). The positive feedback between freeze-thaw cycles and the local stone accumulation (positive or negative) is modeled by a linear production term, while the gravitational reconfiguration gives rise to a cubic nonlinear saturation term. Noise due to fluctuations of the environment is represented by the diffusion term. Similar systems have emerged in wide ranges of physical and chemical problems, yet most of the investigations in the other fields are on stability fields associated with varying control
The Toric Geometry of Triangulated Polygons in Euclidean Space
Howard, Benjamin; Millson, John
2008-01-01
Speyer and Sturmfels [SpSt] associated Gr\\"obner toric degenerations $\\mathrm{Gr}_2(\\C^n)^{\\tree}$ of $\\mathrm{Gr}_2(\\C^n)$ to each trivalent tree $\\tree$ with $n$ leaves. These degenerations induce toric degenerations $M_{\\br}^{\\tree}$ of $M_{\\br}$, the space of $n$ ordered, weighted (by $\\br$) points on the projective line. Our goal in this paper is to give a geometric (Euclidean polygon) description of the toric fibers as stratified symplectic spaces and describe the action of the compact part of the torus as "bendings of polygons." We prove the conjecture of Foth and Hu [FH] that the toric fibers are homeomorphic to the spaces defined by Kamiyama and Yoshida [KY].
Evoluton of polygonal fracture patterns in lava flows.
Aydin, A; Degraff, J M
1988-01-29
Cooling-induced fractures, also known as columnar joints, divide basaltic lava flows into prismatic columns with polygonal cross sections. The regularity and symmetry of the fracture patterns have long fascinated naturalists. In view of the recent selection of two candidate nuclear waste sites in areas where polygonally fractured volcanic rocks are located, a better understanding of the fracture patterns is required. Field data indicate that the tetragonal networks at flow surfaces evolve systematically to hexagonal networks as the joints grow inward during solidification of lava. This evolution occurs by the gradual change of most orthogonal intersections to nonorthogonal intersections of about 120 degrees. The surface features and intersection geometries of columnar joints show that joint segments at any given level form sequentially yet harmoniously.
QUADRATIC SERENDIPITY FINITE ELEMENTS ON POLYGONS USING GENERALIZED BARYCENTRIC COORDINATES.
Rand, Alexander; Gillette, Andrew; Bajaj, Chandrajit
2014-01-01
We introduce a finite element construction for use on the class of convex, planar polygons and show it obtains a quadratic error convergence estimate. On a convex n-gon, our construction produces 2n basis functions, associated in a Lagrange-like fashion to each vertex and each edge midpoint, by transforming and combining a set of n(n + 1)/2 basis functions known to obtain quadratic convergence. The technique broadens the scope of the so-called 'serendipity' elements, previously studied only for quadrilateral and regular hexahedral meshes, by employing the theory of generalized barycentric coordinates. Uniform a priori error estimates are established over the class of convex quadrilaterals with bounded aspect ratio as well as over the class of convex planar polygons satisfying additional shape regularity conditions to exclude large interior angles and short edges. Numerical evidence is provided on a trapezoidal quadrilateral mesh, previously not amenable to serendipity constructions, and applications to adaptive meshing are discussed.
An Operator Product Expansion for Polygonal null Wilson Loops
Alday, Luis F; Maldacena, Juan; Sever, Amit; Vieira, Pedro
2010-01-01
We consider polygonal Wilson loops with null edges in conformal gauge theories. We derive an OPE-like expansion when several successive lines of the polygon are becoming aligned. The limit corresponds to a collinear, or multicollinear, limit and we explain the systematics of all the subleading corrections, going beyond the leading terms that were previously considered. These subleading corrections are governed by excitations of high spin operators, or excitations of a flux tube that goes between two Wilson lines. The discussion is valid for any conformal gauge theory, for any coupling and in any dimension. For N=4 super Yang Mills we check this expansion at strong coupling and at two loops at weak coupling . We also make predictions for the remainder function at higher loops. In the process, we also derived a new version for the TBA integral equations that determine the strong coupling answer and present the area as the associated Yang-Yang functional.
Intracranial meningioma with polygonal granular cell appearance in a Chihuahua.
Takeuchi, Yoshinori; Ohnishi, Yumi; Matsunaga, Satoru; Nakayama, Hiroyuki; Uetsuka, Koji
2008-05-01
A menigioma with polygonal granular cell proliferation in an 11-year and 8-month-old male Chihuahua is described. The tumor was observed under the dura matter of the right cerebrum. Microscopically, the tumor consisted of solid growth foci of small- or large- sized polygonal cells, with pale-stained nuclei, prominent nucleoli, and fine granular to foamy eosinophilic cytoplasm. Some of the proliferating cells contained variable amounts of cytoplasmic PAS-positive granules. Immunohistochemical analysis revealed that neoplastic cells were positive for vimentin and S-100 protein. Ultrastructurally, the neoplastic cells contained vesicular structures with a few small round-shaped bodies in the cytoplasm. We diagnosed the case as canine meningioma with granular cell appearance.
Fat polygonal partitions with applications to visualization and embeddings
Mark de Berg
2013-12-01
Full Text Available Let T be a rooted and weighted tree, where the weight of any node is equal to the sum of the weights of its children. The popular Treemap algorithm visualizes such a tree as a hierarchical partition of a square into rectangles, where the area of the rectangle corresponding to any node in T is equal to the weight of that node. The aspect ratio of the rectangles in such a rectangular partition necessarily depends on the weights and can become arbitrarily high.We introduce a new hierarchical partition scheme, called a polygonal partition, which uses convex polygons rather than just rectangles. We present two methods for constructing polygonal partitions, both having guarantees on the worst-case aspect ratio of the constructed polygons; in particular, both methods guarantee a bound on the aspect ratio that is independent of the weights of the nodes.We also consider rectangular partitions with slack, where the areas of the rectangles may differ slightly from the weights of the corresponding nodes. We show that this makes it possible to obtain partitions with constant aspect ratio. This result generalizes to hyper-rectangular partitions in ℝd. We use these partitions with slack for embedding ultrametrics into d-dimensional Euclidean space: we give a polylog(Δ-approximation algorithm for embedding n-point ultrametrics into ℝd with minimum distortion, where Δ denotes the spread of the metric. The previously best-known approximation ratio for this problem was polynomial in n. This is the first algorithm for embedding a non-trivial family of weighted-graph metrics into a space of constant dimension that achieves polylogarithmic approximation ratio.
Robust design of a polygonal shaft-hub coupling
R. Citarella
2015-10-01
Full Text Available In this work, the Taguchi method is applied for the optimal choice of design parameter values for a polygonal shaft-hub coupling. The objective is to maximize a performance function, minimizing, at the same time, its sensitivity to noises factors (robust design. The Design of Experiments (DoE is adopted to set up a plan of numerical experiments, whose different configurations are simulated using the Boundary Element Method (BEM
Dominant Mode Wave Impedance of Regular Polygonal Waveguides
Vyacheslav V. Komarov
2014-01-01
Full Text Available Polygonal metal waveguides are analyzed analytically and numerically. Classical equation for the wave impedance of arbitrary shaped waveguides is completed with approximate expression for the cutoff wavelength of the dominant mode. Proposed approach is tested with the help of 3D finite difference time domain models of microwave waveguides junctions. Obtained data are used for computer-aided design of microwave transition from coaxial line to cylindrical waveguide.
Quantum Algorithmic Integrability The Metaphor of Polygonal Billiards
Mantica, G
1999-01-01
An elementary application of Algorithmic Complexity Theory to the polygonal approximations of curved billiards-integrable and chaotic-unveils the equivalence of this problem to the procedure of quantization of classical systems: the scaling relations for the average complexity of symbolic trajectories are formally the same as those governing the semi-classical limit of quantum systems. Two cases-the circle, and the stadium-are examined in detail, and are presented as paradigms.
The Area of a Polygon with an Inscribed Circle
Buck, Marshall W
2012-01-01
Heron's formula states that the area $K$ of a triangle with sides $a$, $b$, and $c$ is given by $$ K=\\sqrt {s(s-a) (s-b) (s-c)} $$ where $s$ is the semiperimeter $(a+b+c)/2$. Brahmagupta, Robbins, Roskies, and Maley generalized this formula for polygons of up to eight sides inscribed in a circle. In this paper we derive formulas giving the areas of any $n$-gon, with odd $n$, in terms of the ordered list of side lengths, if the $n$-gon is circumscribed about a circle (instead of being inscribed in a circle). Unlike the cyclic polygon problem, where the order of the sides does not matter, for the inscribed circle problem (our case) it does matter. The solution is much easier than for the cyclic polygon problem, but it does generalize easily to all odd $n$. We also provide necessary and sufficient conditions for there to be solutions in the case of even $n$.
Synthesis and characterisation of polygonal indium tin oxide nanocrystals.
Koo, Bon-Ryul; Park, Byung Kyu; Kim, Chang Yeoul; Oh, Sung-Tag; Ahn, Hyo-Jin
2013-11-01
Polygon ITO (Sn-doped In2O3) nanocrystals were synthesised via electrospinning, and their morphology, structural properties, and chemical composition were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). To determine the optimum conditions for the fabrication of polygon ITO nanocrystals, calcination temperature after the electrospinning process was controlled at 500 degrees C, 600 degrees C, 700 degrees C, and 800 degrees C, and the amount of PVP polymer was controlled at 4 wt%, 7 wt%, and 10 wt%. For comparison purposes, single In2O3 nanocrystals were also synthesised via electrospinning and calcination. The results show that ITO nanocrystals fabricated at a calcination temperature of 800 degrees C and with 10 wt% of PVP polymer exhibit clear polygon structure with single-crystallinity, which may be explained in terms of the effect of Sn doping in the In2O3 matrix and the oriented aggregation and Oswald ripening growth during the fusion process of ITO nanocrystals.
Special properties of Eshelby tensor for a regular polygonal inclusion
Baixiang Xu; Minzhong Wang
2005-01-01
When studying the regular polygonal inclusion in 1997, Nozaki and Taya discovered numerically some remarkable properties of Eshelby tensor: Eshelby tensor at the center and the averaged Eshelby tensor over the inclusion domain are equal to that of a circular inclusion and independent of the orientation of the inclusion. Then Kawashita and Nozaki justified the properties mathematically. In the present paper, some other properties of a regular polygonal inclusion are discovered. We find that for an N-fold regular polygonal inclusion except for a square, the arithmetic mean of Eshelby tensors at N rotational symmetrical points in the inclusion is also equal to the Eshelby tensor for a circular inclusion and independent of the orientation of the inclusion. Furthermore,in two corollaries, we point out that Eshelby tensor at the center, the averaged Eshelby tensor over the inclusion domain,and the line integral average of Eshelby tensors along any concentric circle of the inclusion are all identical with the arithmetic mean.
Brand, Louis
2006-01-01
The use of vectors not only simplifies treatments of differential geometry, mechanics, hydrodynamics, and electrodynamics, but also makes mathematical and physical concepts more tangible and easy to grasp. This text for undergraduates was designed as a short introductory course to give students the tools of vector algebra and calculus, as well as a brief glimpse into these subjects' manifold applications. The applications are developed to the extent that the uses of the potential function, both scalar and vector, are fully illustrated. Moreover, the basic postulates of vector analysis are brou
Modeling bed-load transport of coarse sediments in the Great Bay Estuary, New Hampshire
Bilgili, A.; Swift, M. R.; Lynch, D. R.; Ip, J. T. C.
2003-12-01
Current, sea level and bed-load transport are investigated in the Lower Piscataqua River section of the Great Bay Estuary, New Hampshire, USA—a well-mixed and geometrically complex system with low freshwater input, having main channel tidal currents ranging between 0.5 and 2 m s -1. Current and sea level forced by the M 2M 4M 6 tides at the estuarine mouth are simulated by a vertically averaged, non-linear, time-stepping finite element model. The hydrodynamic model uses a fixed boundary computational domain and accounts for flooding-drying of tidal flats by making use of a groundwater component. Inertia terms are neglected in comparison with pressure gradient and bottom friction terms, which is consistent with the observed principal dynamic balance for this section of the system. The accuracy of hydrodynamic predictions in the study area is demonstrated by comparison with four tidal elevation stations and two cross-section averaged current measurements. Simulated current is then used to model bed-load transport in the vicinity of a rapidly growing shoal located in the main channel of the lower system. Consisting of coarse sand and gravel, the shoal must be dredged every five to eight years. Two approaches are taken—an Eulerian parametric method in which nodal bed-load flux vectors are averaged over the tidal cycle and a Lagrangian particle tracking approach in which a finite number of sediment particles are released and tracked. Both methods yield pathways and accumulations in agreement with the observed shoal formation and the long-term rate of sediment accumulation in the shoal area.
On minimal energy dipole moment distributions in regular polygonal agglomerates
Rosa, Adriano Possebon; Cunha, Francisco Ricardo; Ceniceros, Hector Daniel
2017-01-01
Static, regular polygonal and close-packed clusters of spherical magnetic particles and their energy-minimizing magnetic moments are investigated in a two-dimensional setting. This study focuses on a simple particle system which is solely described by the dipole-dipole interaction energy, both without and in the presence of an in-plane magnetic field. For a regular polygonal structure of n sides with n ≥ 3 , and in the absence of an external field, it is proved rigorously that the magnetic moments given by the roots of unity, i.e. tangential to the polygon, are a minimizer of the dipole-dipole interaction energy. Also, for zero external field, new multiple local minima are discovered for the regular polygonal agglomerates. The number of found local extrema is proportional to [ n / 2 ] and these critical points are characterized by the presence of a pair of magnetic moments with a large deviation from the tangential configuration and whose particles are at least three diameters apart. The changes induced by an in-plane external magnetic field on the minimal energy, tangential configurations are investigated numerically. The two critical fields, which correspond to a crossover with the linear chain minimal energy and with the break-up of the agglomerate, respectively are examined in detail. In particular, the numerical results are compared directly with the asymptotic formulas of Danilov et al. (2012) [23] and a remarkable agreement is found even for moderate to large fields. Finally, three examples of close-packed structures are investigated: a triangle, a centered hexagon, and a 19-particle close packed cluster. The numerical study reveals novel, illuminating characteristics of these compact clusters often seen in ferrofluids. The centered hexagon is energetically favorable to the regular hexagon and the minimal energy for the larger 19-particle cluster is even lower than that of the close packed hexagon. In addition, this larger close packed agglomerate has two
Optimal Polygonal Approximation of Digital Planar Curves Using Genetic Algorithm and Tabu Search
无
2000-01-01
Three heuristic algorithms for optimal polygonal approximation of digital planar curves is presented.With Genetic Algorithm (GA), improved Genetic Algorithm (IGA) based on Pareto optimal solution and Tabu Search (TS), a near optimal polygonal approximation was obtained.Compared to the famous Teh-chin algorithm, our algorithms have obtained the approximated polygons with less number of vertices and less approximation error.Compared to the dynamic programming algorithm, the processing time of our algorithms are much less expensive.
A new definition and calculation for the average normal to a polygon
无
2000-01-01
This paper presents a new definition of the average normal to a polygon by introducing a cone bounded by the polygon, computing its normals and averaging the result. The equivalence of this new definition and that of Newell's is given, and a simple calculation based on this new definition is obtained and 3N additions and N subtractions are saved, where N is the number of the vertices of the polygon.
A new definition and calculation for the average normal to a polygon
梁友栋
2000-01-01
This paper presents a new definition of the average normal to a polygon by introducing a cone bounded by the polygon, computing its normals and averaging the result. The equivalence of this new definition and that of Newell’s is given, and a simple calculation based on this new definition is obtained and 3 N additions and N subtractions are saved, where N is the number of the vertices of the polygon.
Line clipping against polygonal window algorithm based on the multiple virtual boxes rejecting
WANG Jin; LU Guo-dong; PENG Qun-sheng; WU Xuan-hui
2005-01-01
This paper presents a new algorithm for line clipping against a polygonal window by exploiting the local relationship between each line segment and the polygon. Firstly, a minimal enclosing box (MEB) of the polygon is adopted to reject the invisible line segments located outside the MEB. Secondly, a 45° rotated box is used to encode the endpoint of the line segment, and then reject a portion of the invisible segments crossing polygon corners. Finally, instead of encoding the endpoints of all line segments with respect to the polygonal window, each vertex of the polygon is encoded, taking the line segment to be clipped as reference. For efficient encoding of the polygon vertices, a new concept, termed with slope adaptive virtual box, is introduced regarding each line segment. Such a box can not only conveniently reject all totally invisible lines lying outside the MEB conveniently, but also precisely identify the edges of the polygon with which the line segment potentially intersects. With the summation of the vertex codes, it can be verified whether the line segment is separated from or potentially intersects the polygon window. Based on the product of the codes of adjacent vertices, singular cases of intersection can be solved accurately. Experimental results demonstrate the efficiency and stability of the new algorithm.
Guilfoyle, R.A.; Smith, L.M.
1994-12-27
A vector comprising a filamentous phage sequence containing a first copy of filamentous phage gene X and other sequences necessary for the phage to propagate is disclosed. The vector also contains a second copy of filamentous phage gene X downstream from a promoter capable of promoting transcription in a bacterial host. In a preferred form of the present invention, the filamentous phage is M13 and the vector additionally includes a restriction endonuclease site located in such a manner as to substantially inactivate the second gene X when a DNA sequence is inserted into the restriction site. 2 figures.
Guilfoyle, Richard A.; Smith, Lloyd M.
1994-01-01
A vector comprising a filamentous phage sequence containing a first copy of filamentous phage gene X and other sequences necessary for the phage to propagate is disclosed. The vector also contains a second copy of filamentous phage gene X downstream from a promoter capable of promoting transcription in a bacterial host. In a preferred form of the present invention, the filamentous phage is M13 and the vector additionally includes a restriction endonuclease site located in such a manner as to substantially inactivate the second gene X when a DNA sequence is inserted into the restriction site.
The Knot Spectrum of Confined Random Equilateral Polygons
Diao Y.
2014-01-01
Full Text Available It is well known that genomic materials (long DNA chains of living organisms are often packed compactly under extreme confining conditions using macromolecular self-assembly processes but the general DNA packing mechanism remains an unsolved problem. It has been proposed that the topology of the packed DNA may be used to study the DNA packing mechanism. For example, in the case of (mutant bacteriophage P4, DNA molecules packed inside the bacteriophage head are considered to be circular since the two sticky ends of the DNA are close to each other. The DNAs extracted from the capsid without separating the two ends can thus preserve the topology of the (circular DNAs. It turns out that the circular DNAs extracted from bacteriophage P4 are non-trivially knotted with very high probability and with a bias toward chiral knots. In order to study this problem using a systematic approach based on mathematical modeling, one needs to introduce a DNA packing model under extreme volume confinement condition and test whether such a model can produce the kind of knot spectrum observed in the experiments. In this paper we introduce and study a model of equilateral random polygons con_ned in a sphere. This model is not meant to generate polygons that model DNA packed in a virus head directly. Instead, the average topological characteristics of this model may serve as benchmark data for totally randomly packed circular DNAs. The difference between the biologically observed topological characteristics and our benchmark data might reveal the bias of DNA packed in the viral capsids and possibly lead to a better understanding of the DNA packing mechanism, at least for the bacteriophage DNA. The purpose of this paper is to provide information about the knot spectrum of equilateral random polygons under such a spherical confinement with length and confinement ratios in a range comparable to circular DNAs packed inside bacteriophage heads.
The average crossing number of equilateral random polygons
Diao, Y.; Dobay, A.; Kusner, R. B.; Millett, K.; Stasiak, A.
2003-11-01
In this paper, we study the average crossing number of equilateral random walks and polygons. We show that the mean average crossing number ACN of all equilateral random walks of length n is of the form \\frac{3}{16} n \\ln n +O(n) . A similar result holds for equilateral random polygons. These results are confirmed by our numerical studies. Furthermore, our numerical studies indicate that when random polygons of length n are divided into individual knot types, the \\langle ACN({\\cal K})\\rangle for each knot type \\cal K can be described by a function of the form \\langle ACN({\\cal K})\\rangle=a (n-n_0) \\ln (n-n_0)+b (n-n_0)+c where a, b and c are constants depending on \\cal K and n0 is the minimal number of segments required to form \\cal K . The \\langle ACN({\\cal K})\\rangle profiles diverge from each other, with more complex knots showing higher \\langle ACN({\\cal K})\\rangle than less complex knots. Moreover, the \\langle ACN({\\cal K})\\rangle profiles intersect with the langACNrang profile of all closed walks. These points of intersection define the equilibrium length of \\cal K , i.e., the chain length n_e({\\cal K}) at which a statistical ensemble of configurations with given knot type \\cal K —upon cutting, equilibration and reclosure to a new knot type \\cal K^\\prime —does not show a tendency to increase or decrease \\langle ACN({\\cal K^\\prime)}\\rangle . This concept of equilibrium length seems to be universal, and applies also to other length-dependent observables for random knots, such as the mean radius of gyration langRgrang.
Kim Pawlawski; Robert A. Robertson; Laura Pfister
2003-01-01
This study was intended to provide New Hampshire agencies with a better understanding of public access-related demand information. Through an analysis of three groups of New Hampshire residents based upon geographic location and length of residency, important issues and attitudes were identified from all over the State. The results of this study will assist in policy-...
Polygonal triple (Kotz) osteotomy (over 10 years experience)
Sen, Cengiz; Gunes, Taner; Erdem, Mehmet; Ozger, Harzem; Tozun, I. Remzi
2006-01-01
We evaluated the results of polygonal triple (Kotz) osteotomy for the treatment of acetabular dysplasia over 10 years. This study included 31 hips of 27 patients who had the Kotz osteotomy for acetabular dysplasia. The mean age was 21.5 years. We performed the original Kotz osteotomy for the first 22 hips (group I), while the modified Kotz osteotomy through an intra-pelvic approach without damage to the abductor muscle was applied for the last 9 hips (group II). Patients were evaluated by cli...
A New Heuristic Constructing Minimal Steiner Trees inside Simple Polygons
Alireza Khosravinejad
2013-07-01
Full Text Available The Steiner tree problem has numerous applications in urban transportation network, design of electronic integrated circuits, and computer network routing. This problem aims at finding a minimum Steiner tree in the Euclidean space, the distance between each two edges of which has the least cost. This problem is considered as an NP-hard one. Assuming the simple polygon P with m vertices and n terminals, the purpose of the minimum Steiner tree in the Euclidean space is to connect the n terminals existing in p. In the proposed algorithm, obtaining optimal responses will be sought by turning this problem into the Steiner tree problem on a graph.
Water-quality conditions in southern Rockingham County, New Hampshire
Silvey, William Dudley; Wheeler, Robert L.
1978-01-01
Physical, chemical, and biological characteristics of water were measured at 26 surface-water sites, 17 ground-water sites, and in effluent from two sanitary landfills as part of planning for area-wide waste management in four watersheds within the Southern Rockingham Regional Planning District in Southern New Hampshire. Dissolved minerals concentration in water at all but one of 26 surface-water-sampling sites is low and within recommended limits of the U.S. Environmental Protection Agency. Water at the 26 surface-water-sampling sites generally was enriched with nitrogen and phosphorus and contained at least some coliform bacteria, indicating contamination, probably from waste disposal systems. PCBs (polychlorinated biphenyls) and pesticides were not present in the water, but small amounts of DDE, DDD, dieldrin, chlordane, and heptachlor were present in stream-bottom materials at 11 of the 26 sites, and PCBs were present at 7. Iron and manganese were present in concentrations that in some cases exceeded recommended limits. Coliform bacteria were present at 5 of the 17 ground-water-sampling sites; concentrations of iron exceeded recommended limits at 8 sites, and manganese exceeded recommended limits at 9 sites. PCBs and pesticides were not present in any samples collected at the ground-water-sampling sites. (Woodard-USGS)
Gaseous elemental and reactive mercury in southern New Hampshire
J. M. Sigler
2008-09-01
Full Text Available We conducted measurements of Hg° and RGM at two inland sites, Thompson Farm (TF and Pac Monadnock (PM, and a marine site (Appledore Island – AI from the UNH AIRMAP observing network in New Hampshire in 2007. Measurements of other important trace gases and meteorological variables were used to help understand influences on the atmospheric Hg budget in New England. Seasonal variation in both species observed at TF and PM is attributable to such factors as seasonal variation in deposition strength, meteorological conditions and biogenic emissions. Hg° and RGM varied diurnally at TF, particularly in spring, following the trend in air temperature and jNO_{2} and suggesting photochemical production of RGM. The diurnal patterns of Hg° and RGM at AI during summer were nearly opposite in phase, with Hg° decreasing through late afternoon, suggesting more significant photochemical oxidation of Hg° to RGM in the marine environment, likely due to the presence of marine halogen compounds. A strong relationship of RGM with SO_{2} at TF suggests a strong contribution of RGM from anthropogenic sources. Significant levels of halogen compounds measured at TF in previous studies, as well as similar Hg° levels and Hg°-CO ratios at TF and AI may suggest that similar air masses are prevalent at these sites.
Giant polygons and mounds in the lowlands of Mars: signatures of an ancient ocean?
Oehler, Dorothy Z; Allen, Carlton C
2012-06-01
This paper presents the hypothesis that the well-known giant polygons and bright mounds of the martian lowlands may be related to a common process-a process of fluid expulsion that results from burial of fine-grained sediments beneath a body of water. Specifically, we hypothesize that giant polygons and mounds in Chryse and Acidalia Planitiae are analogous to kilometer-scale polygons and mud volcanoes in terrestrial, marine basins and that the co-occurrence of masses of these features in Chryse and Acidalia may be the signature of sedimentary processes in an ancient martian ocean. We base this hypothesis on recent data from both Earth and Mars. On Earth, 3-D seismic data illustrate kilometer-scale polygons that may be analogous to the giant polygons on Mars. The terrestrial polygons form in fine-grained sediments that have been deposited and buried in passive-margin, marine settings. These polygons are thought to result from compaction/dewatering, and they are commonly associated with fluid expulsion features, such as mud volcanoes. On Mars, in Chryse and Acidalia Planitiae, orbital data demonstrate that giant polygons and mounds have overlapping spatial distributions. There, each set of features occurs within a geological setting that is seemingly analogous to that of the terrestrial, kilometer-scale polygons (broad basin of deposition, predicted fine-grained sediments, and lack of significant horizontal stress). Regionally, the martian polygons and mounds both show a correlation to elevation, as if their formation were related to past water levels. Although these observations are based on older data with incomplete coverage, a similar correlation to elevation has been established in one local area studied in detail with newer higher-resolution data. Further mapping with the latest data sets should more clearly elucidate the relationship(s) of the polygons and mounds to elevation over the entire Chryse-Acidalia region and thereby provide more insight into this
Origami tubes with reconfigurable polygonal cross-sections.
Filipov, E T; Paulino, G H; Tachi, T
2016-01-01
Thin sheets can be assembled into origami tubes to create a variety of deployable, reconfigurable and mechanistically unique three-dimensional structures. We introduce and explore origami tubes with polygonal, translational symmetric cross-sections that can reconfigure into numerous geometries. The tubular structures satisfy the mathematical definitions for flat and rigid foldability, meaning that they can fully unfold from a flattened state with deformations occurring only at the fold lines. The tubes do not need to be straight and can be constructed to follow a non-linear curved line when deployed. The cross-section and kinematics of the tubular structures can be reprogrammed by changing the direction of folding at some folds. We discuss the variety of tubular structures that can be conceived and we show limitations that govern the geometric design. We quantify the global stiffness of the origami tubes through eigenvalue and structural analyses and highlight the mechanical characteristics of these systems. The two-scale nature of this work indicates that, from a local viewpoint, the cross-sections of the polygonal tubes are reconfigurable while, from a global viewpoint, deployable tubes of desired shapes are achieved. This class of tubes has potential applications ranging from pipes and micro-robotics to deployable architecture in buildings.
Transit Traffic Analysis Zone Delineating Method Based on Thiessen Polygon
Shuwei Wang
2014-04-01
Full Text Available A green transportation system composed of transit, busses and bicycles could be a significant in alleviating traffic congestion. However, the inaccuracy of current transit ridership forecasting methods is imposing a negative impact on the development of urban transit systems. Traffic Analysis Zone (TAZ delineating is a fundamental and essential step in ridership forecasting, existing delineating method in four-step models have some problems in reflecting the travel characteristics of urban transit. This paper aims to come up with a Transit Traffic Analysis Zone delineation method as supplement of traditional TAZs in transit service analysis. The deficiencies of current TAZ delineating methods were analyzed, and the requirements of Transit Traffic Analysis Zone (TTAZ were summarized. Considering these requirements, Thiessen Polygon was introduced into TTAZ delineating. In order to validate its feasibility, Beijing was then taken as an example to delineate TTAZs, followed by a spatial analysis of office buildings within a TTAZ and transit station departure passengers. Analysis result shows that the TTAZs based on Thiessen polygon could reflect the transit travel characteristic and is of in-depth research value.
Genetic differentiation between 'Araucana' creole and 'Hampshire Down' sheeps in Chile
Silvana Bravo
2015-03-01
Full Text Available Genetic diversity studies in domestic animals allow evaluating genetic variation within and among breeds mainly for conservation purposes. In Chile exist isolated recovery programs, conservation and characterization of animal genetic resources, a consequence of which the vast majority of them have not been characterized, poorly used, and some of them have become extinct. The aim of this research was to determine genetic diversity and relationship between 'Araucana' creole and 'Hampshire Down' sheeps based on microsatellite markers; sheep breeds with similar phenotypic characteristics, raised in the south of Chile. A total of 64 'Araucana' sheep ('Araucana' from Freire, AF: 27, 'Araucana' from Padre Las Casas, AP: 10, 'Araucana' from Chol Chol, AC: 15, 'Araucana' from Villarrica, AV: 12 and 43 'Hampshire Down' sheep ('Hampshire' from Marchigue, HM: 18, 'Hampshire' from Valdivia, HV: 11, 'Hampshire' from San José, HS: 14 were analyzed using 17 microsatellite markers for determine the genetic diversity and relationship between breeds. A total of 284 alleles were observed with average polymorphic information content equal to 0.76, showing that the microsatellites panel used was highly informative. Estimated heterozygosity ranged from 0.73 in 'Hampshire Down' to 0.85 in 'Araucana'. The low inbreeding or endogamy coefficient (F IS, 0.022 and total inbreeding estimate (F IT, 0.070 indicated low level of inbreeding within and among breeds. The phylogenetic tree showed a separation between HS and HV, and the other sheep populations. The results indicated high genetic variability, low inbreeding, and low genetic differentiation, except for HV and HS, and were in according with geographical location and breeding practices.
Degnan, James; Barker, Gregory; Olson, Neil; Wilder, Leland
2012-01-01
The U.S. Geological Survey, in cooperation with the New Hampshire Geological Survey, measured the fluid temperature of groundwater in deep bedrock wells in the State of New Hampshire in order to characterize geothermal gradients in bedrock. All wells selected for the study had low water yields, which correspond to low groundwater flow from fractures. This reduced the potential for flow-induced temperature changes that would mask the natural geothermal gradient in the bedrock. All the wells included in this study were privately owned, and permission to use the wells was obtained from homeowners before logging.
Mass treatment of humans exposed to rabies--New Hampshire, 1994.
1995-07-07
On October 22, 1994, the laboratory of the New Hampshire Division of Public Health Services (NHDPHS) diagnosed rabies in a kitten that had been purchased from a pet store in Concord, New Hampshire. On October 19, the animal had developed seizures, then died of unknown causes during the night of October 20-21. Approximately 665 persons received rabies postexposure prophylaxis because of exposure to this kitten and other cats from the same pet store. This report summarizes the epidemiologic investigation of the source of the infection and follow-up care of humans and animals potentially exposed to rabies.
KiMPA: A Kinematics-Based Method for Polygon Approximation
Yakhno, T.M.; Saykol, E.; Gülesir, G.; Gudukbay, U.; Ulusoy, Ö.
2002-01-01
In different types of information systems, such as multimedia information systems and geographic information systems, object-based information is represented via polygons corresponding to the boundaries of object regions. In many applications, the polygons have large number of vertices and edges,
Hierarchical vertical decompositions, ray shooting, and circular arc queries in simple polygons
Oostrum, R. van; Ahn, Hee-Kap; Cheng, S.-W.; Golin, Mordecai
1999-01-01
A new hierarchical decomposition of a simple polygon is introduced. The hierarchy has depth O(log n), linear size, and its regions have maximum degree three. Using this hierarchy, circular ray shooting queries in a simple polygon can be answered in O(log* n) query time and O(nlogn) space. If the rad
On the Computation of the Moments of a Polygon, with some Applications
Soerjadi, R.
1968-01-01
A general formula for moments of a polygon is derived. The concept of 'moment' is a generalization of the statical, inertial and centrifugal moment respectively of a polygon, which as such are special moments of first and second order. Moments of higher order, however, also have applications in engi
A numerical investigation of sub-wavelength resonances in polygonal metamaterial cylinders
Arslanagic, Samel; Breinbjerg, Olav
2009-01-01
of polygonal cylinders excited by a nearby electric line current is analyzed numerically and it is shown, through detailed analysis of the near-field distribution and radiation resistance, that these polygonal cylinders do indeed support sub-wavelength resonances similar to those of the circular cylinders...
Engaging Communities Where They Are: New Hampshire's Coastal Adaptation Workgroup
Wake, C. P.; Godlewski, S.; Howard, K.; Labranche, J.; Miller, S.; Peterson, J.; Ashcraft, C.
2015-12-01
Rising seas are expected to have significant impacts on infrastructure and natural and cultural resources on New Hampshire's 18 mile open-ocean coastline and 235 miles of tidal shoreline. However, most coastal municipalities in NH lack financial and human resources to even assess vulnerability, let alone plan for climate change. This gap has been filled since 2010 by the NH Coastal Adaptation Workgroup (CAW), composed of 21 regional, state, and federal agencies, businesses, municipalities, academics, and NGOs that bring together stakeholders to discuss climate change challenges and collaboratively develop and implement effective coastal adaptation strategies. Our grassroot efforts serve to nurture existing and build new relationships, disseminate coastal watershed climate assessments, and tap into state, federal, and foundation funds for specific coastal adaptation projects. CAW has achieved collective impact in by connecting federal and state resources to communities by raising money and facilitating projects, translating climate science, educating community members, providing direct technical assistance and general capacity, and sharing success stories and lessons learned. Indicators of success include: 12 coastal communities improved their technical, financial, and human resources for climate adaptation; 80% of the 300 participants in the eleven CAW 'Water, Weather, Climate, and Community Workshops' have increased knowledge, motivation, and capacity to address climate adaptation; $3 million in grants to help communities with climate adaptation; winner of the 2015 EPA Region 1 Environmental Merit Award; and ongoing support for community-led adaptation efforts. In addition, the NH Climate Summit attracts over 100 participants each year, over 90% whom attest to the applicability of what they learn there. CAW also plays a central role in the Coastal Risks and Hazards Commission (established by the state legislature in 2013) to help communities and businesses prepare
Infrared Technology And Public Schools: Applications In Berlin, New Hampshire
Perrin, Alan F.
1981-01-01
Infrared technology played an important part in dealing with school energy problems in Berlin, New Hampshire. It provided the school board and administration with information and data which proved useful in prioritizing the expenditure of limited capital improvement funds. It enabled the board and administration to diagnose the extent of building heat loss problems and compare the heating oil component of our energy problems with independently diagnosed electricity and gasoline components. Since seventy (70) percent of school energy expenditures are on heating oil, infrared assumed the role of a very important diagnostic tool. The Berlin (NH) Public Schools manifest problems faced by public schools in many areas of the country; declining enrollments, inflation, and taxpayer resistance to increasing public expenditures. With eight buildings to heat and light (six schools, a bus garage, and a vocational forestry building), rapidly escalating energy prices threatened to raise total school energy costs as a percentage of total budget from less than seven (7) percent to almost twenty (20) percent, unless consumption reductions were effected. There were minimal obstacles to infrared implementation in Berlin, for a number of reasons. First, the cost was not prohibitive. Second, there was little community understanding of the technology along with an historic separation of specific, relatively low cost school expenditures from close public scrutiny. Finally, the school board and administration realized that, if the energy problem was to be adequately dealt with, a clear understanding of the problem was necessary. The best way for that understanding to be developed was through professional examination of our buildings using the most modern techniques. At this juncture, after only one winter, it is clear that the payback period for Berlin's investment in infrared technology has been surpassed.
Robinson, Gilbert de B
2011-01-01
This brief undergraduate-level text by a prominent Cambridge-educated mathematician explores the relationship between algebra and geometry. An elementary course in plane geometry is the sole requirement for Gilbert de B. Robinson's text, which is the result of several years of teaching and learning the most effective methods from discussions with students. Topics include lines and planes, determinants and linear equations, matrices, groups and linear transformations, and vectors and vector spaces. Additional subjects range from conics and quadrics to homogeneous coordinates and projective geom
The average inter-crossing number of equilateral random walks and polygons
Diao, Y.; Dobay, A.; Stasiak, A.
2005-09-01
In this paper, we study the average inter-crossing number between two random walks and two random polygons in the three-dimensional space. The random walks and polygons in this paper are the so-called equilateral random walks and polygons in which each segment of the walk or polygon is of unit length. We show that the mean average inter-crossing number ICN between two equilateral random walks of the same length n is approximately linear in terms of n and we were able to determine the prefactor of the linear term, which is a=\\frac{3\\ln 2}{8}\\approx 0.2599 . In the case of two random polygons of length n, the mean average inter-crossing number ICN is also linear, but the prefactor of the linear term is different from that of the random walks. These approximations apply when the starting points of the random walks and polygons are of a distance ρ apart and ρ is small compared to n. We propose a fitting model that would capture the theoretical asymptotic behaviour of the mean average ICN for large values of ρ. Our simulation result shows that the model in fact works very well for the entire range of ρ. We also study the mean ICN between two equilateral random walks and polygons of different lengths. An interesting result is that even if one random walk (polygon) has a fixed length, the mean average ICN between the two random walks (polygons) would still approach infinity if the length of the other random walk (polygon) approached infinity. The data provided by our simulations match our theoretical predictions very well.
Deformations of polyhedra and polygons by the unitary group
Livine, Etera R.
2013-12-01
We introduce the set of framed (convex) polyhedra with N faces as the symplectic quotient {{C}}^{2N}//SU(2). A framed polyhedron is then parametrized by N spinors living in {{C}}2 satisfying suitable closure constraints and defines a usual convex polyhedron plus extra U(1) phases attached to each face. We show that there is a natural action of the unitary group U(N) on this phase space, which changes the shape of faces and allows to map any (framed) polyhedron onto any other with the same total (boundary) area. This identifies the space of framed polyhedra to the Grassmannian space U(N)/ (SU(2)×U(N-2)). We show how to write averages of geometrical observables (polynomials in the faces' area and the angles between them) over the ensemble of polyhedra (distributed uniformly with respect to the Haar measure on U(N)) as polynomial integrals over the unitary group and we provide a few methods to compute these integrals systematically. We also use the Itzykson-Zuber formula from matrix models as the generating function for these averages and correlations. In the quantum case, a canonical quantization of the framed polyhedron phase space leads to the Hilbert space of SU(2) intertwiners (or, in other words, SU(2)-invariant states in tensor products of irreducible representations). The total boundary area as well as the individual face areas are quantized as half-integers (spins), and the Hilbert spaces for fixed total area form irreducible representations of U(N). We define semi-classical coherent intertwiner states peaked on classical framed polyhedra and transforming consistently under U(N) transformations. And we show how the U(N) character formula for unitary transformations is to be considered as an extension of the Itzykson-Zuber to the quantum level and generates the traces of all polynomial observables over the Hilbert space of intertwiners. We finally apply the same formalism to two dimensions and show that classical (convex) polygons can be described in a
A formula for crossing probabilities of critical systems inside polygons
Flores, S. M.; Simmons, J. J. H.; Kleban, P.; Ziff, R. M.
2017-02-01
In this article, we use our results from Flores and Kleban (2015 Commun. Math. Phys. 333 389-434, 2015 Commun. Math. Phys. 333 435-81, 2015 Commun. Math. Phys. 333 597-667, 2015 Commun. Math. Phys. 333 669-715) to generalize known formulas for crossing probabilities. Prior crossing results date back to Cardy’s prediction of a formula for the probability that a percolation cluster in two dimensions connects the left and right sides of a rectangle at the percolation critical point in the continuum limit (Cardy 1992 J. Phys. A: Math. Gen. 25 L201-6). Here, we predict a new formula for crossing probabilities of a continuum limit loop-gas model on a planar lattice inside a 2N-sided polygon. In this model, boundary loops exit and then re-enter the polygon through its vertices, with exactly one loop passing once through each vertex, and these loops join the vertices pairwise in some specified connectivity through the polygon’s exterior. The boundary loops also connect the vertices through the interior, which we regard as a crossing event. For particular values of the loop fugacity, this formula specializes to FK cluster (resp. spin cluster) crossing probabilities of a critical Q-state random cluster (resp. Potts) model on a lattice inside the polygon in the continuum limit. This includes critical percolation as the Q = 1 random cluster model. These latter crossing probabilities are conditioned on a particular side-alternating free/fixed (resp. fluctuating/fixed) boundary condition on the polygon’s perimeter, related to how the boundary loops join the polygon’s vertices pairwise through the polygon’s exterior in the associated loop-gas model. For Q\\in ≤ft\\{2,3,4\\right\\} , we compare our predictions of these random cluster (resp. Potts) model crossing probabilities in a rectangle (N = 2) and in a hexagon (N = 3) with high-precision computer simulation measurements. We find that the measurements agree with our predictions very
Numerical aspects of spectral segmentation on polygonal grids
Matsekh, Anna [Los Alamos National Laboratory; Skurikhin, Alexei [Los Alamos National Laboratory; Prasad, Lakshman [Los Alamos National Laboratory; Rosten, Edward [UNIV OF CAMBRIDGE
2010-01-01
The authors analyze numerical behavior of the spectral graph partitioning problem arising in the Normalized Cuts formulation of the image segmentation problem on polygonal grids. They make an observation that in the presence of rounding errors the eigenvector corresponding to the k-th smallest eigenvalue of the generalized graph Laplacian should contain more than k nodal domains that represent coherent segments in the image. As the result, the eigenvector corresponding to the trivial solution carries a wealth of information about the nodal domains in the image and can be used as an initial guess for the Krylov subspace eigensolver, while the computed eigenvector subspace, corresponding to just a few of the lowest eigenvalues of the graph Laplacian, will contain sufficient information for obtaining meaningful segmentation.
Optimal placement of convex polygons to maximize point containment
Dickerson, M. [Middlebury College, VT (United States); Scharstein, D. [Cornell Univ., Ithaca, NY (United States)
1996-12-31
Given a convex polygon P with m vertices and a set S of n points in the plane, we consider the problem of finding a placement of P that contains the maximum number of points in S. We allow both translation and rotation. Our algorithm is self-contained and utilizes the geometric properties of the containing regions in the parameter space of transformations. The algorithm requires O(nk{sup 2} m{sup 2} log(mk)) time and O(n + m) space, where k is the maximum number of points contained. This provides a linear improvement over the best previously known algorithm when k is large ({Theta}(n)) and a cubic improvement when k is small. We also show that the algorithm can be extended to solve bichromatic and general weighted variants of the problem.
Polygonal triple (Kotz) osteotomy (over 10 years experience).
Sen, Cengiz; Gunes, Taner; Erdem, Mehmet; Ozger, Harzem; Tozun, I Remzi
2007-06-01
We evaluated the results of polygonal triple (Kotz) osteotomy for the treatment of acetabular dysplasia over 10 years. This study included 31 hips of 27 patients who had the Kotz osteotomy for acetabular dysplasia. The mean age was 21.5 years. We performed the original Kotz osteotomy for the first 22 hips (group I), while the modified Kotz osteotomy through an intra-pelvic approach without damage to the abductor muscle was applied for the last 9 hips (group II). Patients were evaluated by clinically and radiologically. The average follow-up was 106 months in group I, and 18 months in group II. The Trendelenburg gait was unchanged for four patients in group I and for one patient in group II. The Harris Hip Score improved in all patients postoperatively. Radiographic assesment showed improvement in both groups in terms of the angle of CE, VCE, and Sharp postoperatively(PTrendelenburg gait compared to the original Kotz osteotomy.
A Facile Method for Synthesis of Polygonal Silver Nanopartilces
无
2006-01-01
The synthesis of nanosized powders and their assembly is of considerable importance to the microelectronics industry because of the pervasive drive to miniaturize components. In this work, silver (Ag) nanoparticls was syntheized. Polygonal silver nanoparticls were synthesized by reacting AgNO3 with hydroquinone, in the presence of poly-(vinylpyrrolidone) (PVP) and an ionic liquid 1-n-butyl-3-methylimidazolium hexafluoroborate ([BMIM]·PF6) at ambient temperature. XRD shows that the crystal structure of the nanoparticles is face-centered cubic. TEM measurements display the silver particles with uniform size and narrow particle size distributions. The UV-Vis spectra of the nanoplates distinguish from those of the samples prepared in the absence of PVP and/or ILs. This method is facile and the as-prepared silver nanoparticls are also stable in some solvents, such as ethanol and water.
Reachability by paths of bounded curvature in a convex polygon
Ahn, Heekap
2012-01-01
Let B be a point robot moving in the plane, whose path is constrained to forward motions with curvature at most 1, and let P be a convex polygon with n vertices. Given a starting configuration (a location and a direction of travel) for B inside P, we characterize the region of all points of P that can be reached by B, and show that it has complexity O(n). We give an O(n2) time algorithm to compute this region. We show that a point is reachable only if it can be reached by a path of type CCSCS, where C denotes a unit circle arc and S denotes a line segment. © 2011 Elsevier B.V.
Treks into intuitive geometry the world of polygons and polyhedra
Akiyama, Jin
2015-01-01
This book is written in a style that uncovers the mathematical theories buried in our everyday lives such as examples from patterns that appear in nature, art, and traditional crafts, and in mathematical mechanisms in techniques used by architects. The authors believe that through dialogues between students and mathematicians, readers may discover the processes by which the founders of the theories came to their various conclusions―their trials, errors, tribulations, and triumphs. The goal is for readers to refine their mathematical sense of how to find good questions and how to grapple with these problems. Another aim is to provide enjoyment in the process of applying mathematical rules to beautiful art and design by examples that highlight the wonders and mysteries from our daily lives. To fulfill these aims, this book deals with the latest unique and beautiful results in polygons and polyhedra and the dynamism of geometrical research history that can be found around us. The term "intuitive geometry" was ...
Convergence of Wachspress coordinates: from polygons to curved domains
Kosinka, Jiří
2014-08-08
Given a smooth, strictly convex planar domain, we investigate point-wise convergence of the sequence of Wachspress coordinates defined over finer and finer inscribed polygonal approximations of the domain. Based on a relation between the discrete Wachspress case and the limit smooth case given by the Wachspress kernel defined by Warren et al., we show that the corresponding sequences of Wachspress interpolants and mappings converge as 𝓞(h2) for a sampling step size h of the boundary curve of the domain as h → 0. Several examples are shown to numerically validate the results and to visualise the behaviour of discrete interpolants and mappings as they converge to their smooth counterparts. Empirically, the same convergence order is observed also for mean value coordinates. Moreover, our numerical tests suggest that the convergence of interpolants and mappings is uniform both in the Wachspress and mean value cases. © 2014 Springer Science+Business Media New York.
Quadratic Serendipity Finite Elements on Polygons Using Generalized Barycentric Coordinates
Rand, Alexander; Bajaj, Chandrajit
2011-01-01
We introduce a finite element construction for use on the class of convex, planar polygons and show it obtains a quadratic error convergence estimate. On a convex n-gon satisfying simple geometric criteria, our construction produces 2n basis functions, associated in a Lagrange-like fashion to each vertex and each edge midpoint, by transforming and combining a set of n(n+1)/2 basis functions known to obtain quadratic convergence. The technique broadens the scope of the so-called `serendipity' elements, previously studied only for quadrilateral and regular hexahedral meshes, by employing the theory of generalized barycentric coordinates. Numerical evidence is provided on a trapezoidal quadrilateral mesh, previously not amenable to serendipity constructions, and applications to adaptive meshing are discussed.
Occurrence of normal and anomalous diffusion in polygonal billiard channels.
Sanders, David P; Larralde, Hernán
2006-02-01
From extensive numerical simulations, we find that periodic polygonal billiard channels with angles which are irrational multiples of pi generically exhibit normal diffusion (linear growth of the mean squared displacement) when they have a finite horizon, i.e., when no particle can travel arbitrarily far without colliding. For the infinite horizon case we present numerical tests showing that the mean squared displacement instead grows asymptotically as t ln t. When the unit cell contains accessible parallel scatterers, however, we always find anomalous super-diffusion, i.e., power-law growth with an exponent larger than . This behavior cannot be accounted for quantitatively by a simple continuous-time random walk model. Instead, we argue that anomalous diffusion correlates with the existence of families of propagating periodic orbits. Finally we show that when a configuration with parallel scatterers is approached there is a crossover from normal to anomalous diffusion, with the diffusion coefficient exhibiting a power-law divergence.
Spatial variability of CO2 uptake in polygonal tundra
Pirk, Norbert; Sievers, Jakob; Mertes, Jordan
2017-01-01
with an unmanned aerial vehicle (UAV) that mapped ice-wedge morphology to complement eddy covariance (EC) flux measurements of CO2. The analysis of spectral distributions showed that conventional EC methods do not accurately capture the turbulent CO2 exchange with a spatially heterogeneous surface that typically......The large spatial variability in Arctic tundra complicates the representative assessment of CO2 budgets. Accurate measurements of these heterogeneous landscapes are, however, essential to understanding their vulnerability to climate change. We surveyed a polygonal tundra lowland on Svalbard...... features small flux magnitudes. Nonlocal (low-frequency) flux contributions were especially pronounced during snow melt and introduced a large bias of -46 gC m(-2) to the annual CO2 budget in conventional methods (the minus sign indicates a higher uptake by the ecosystem). Our improved flux calculations...
Modeling slow deformation of polygonal particles using DEM
无
2008-01-01
We introduce two improvements in the numerical scheme to simulate collision and slow shearing of irregular particles. First, we propose an alternative approach based on simple relations to compute the frictional contact forces. The approach improves efficiency and accuracy of the Discrete Element Method (DEM) when modeling the dynamics of the granular packing. We determine the proper upper limit for the integration step in the standard numerical scheme using a wide range of material parameters. To this end, we study the kinetic energy decay in a stress controlled test between two particles. Second, we show that the usual way of defining the contact plane between two polygonal particles is, in general, not unique which leads to discontinuities in the direction of the contact plane while particles move. To solve this drawback, we introduce an accurate definition for the contact plane based on the shape of the overlap area between touching particles, which evolves continuously in time.
Generalized Swept Mid-structure for Polygonal Models
Martin, Tobias
2012-05-01
We introduce a novel mid-structure called the generalized swept mid-structure (GSM) of a closed polygonal shape, and a framework to compute it. The GSM contains both curve and surface elements and has consistent sheet-by-sheet topology, versus triangle-by-triangle topology produced by other mid-structure methods. To obtain this structure, a harmonic function, defined on the volume that is enclosed by the surface, is used to decompose the volume into a set of slices. A technique for computing the 1D mid-structures of these slices is introduced. The mid-structures of adjacent slices are then iteratively matched through a boundary similarity computation and triangulated to form the GSM. This structure respects the topology of the input surface model is a hybrid mid-structure representation. The construction and topology of the GSM allows for local and global simplification, used in further applications such as parameterization, volumetric mesh generation and medical applications.
Evolving fracture patterns: columnar joints, mud cracks, and polygonal terrain
Goehring, L.
2012-12-01
Contraction cracks can form captivating patterns, such as the artistic craquelure sometimes found in pottery glazes, to the cracks in dried mud, or the polygonal networks covering the polar regions of Earth and Mars. Two types are frequently encountered: those with irregular rectilinear patterns, such as that formed by an homogeneous slurry when dried (or cooled) uniformly, and more regular hexagonal patterns, such as those typified by columnar joints. Once cracks start to form in a thin contracting layer, they will sequentially break the layer into smaller and smaller pieces. A rectilinear crack pattern encodes information about the order of cracks, as later cracks tend to intersect with earlier cracks at right angles. In this manner they relieve the stresses perpendicular to the pre-existing crack. In a hexagonal pattern, in contrast, the angles between all cracks at a vertex are near 120°. In this presentation it will be shown how both types of pattern can arise from identical forces, and that a rectilinear, T-junction dominated pattern will develop into to a hexagonal pattern, with Y-junctions, if allowed to. Such an evolution can be explained as the result of three conditions: (1) if cracks advance through space, or heal and recur, that the previous positions of a crack tip acts as a line of weakness, guiding the next iteration of cracking; (2) that the order of opening of cracks can change in each iteration; and (3) that crack tips curve to maximise the local strain energy release rate. The ordering of crack patterns are seen in a number of systems: columnar joints in starch and lava; desiccation cracks in clays that are repeatedly wetted and dried; cracks in eroding gypsum-cemented sand layers; and the cracks in permafrost known as polygonal terrain. These patterns will each be briefly explored, in turn, and shown to obey the above principles of crack pattern evolution.
Ben Amsden; Thad Guldbrandsen; Mark. Okrant
2012-01-01
Nostalgia tourism is an emerging phenomenon in which visitors actively seek to relive their experiences and/or perceptions of yesteryear. How can modern-day tourism development best leverage this desire to reexperience the past? The Institute for New Hampshire Studies and the Center for Rural Partnerships at Plymouth State University sought to answer this question by...
An evaluation of the Regional Mercury Cycling Model (R-MCM, a steady-state fate and transport model used to simulate mercury concentrations in lakes) is presented based on its application to a series of 91 lakes in Vermont and New Hampshire. Visual and statistical analyses are pr...
33 CFR 165.106 - Security Zone: Seabrook Nuclear Power Plant, Seabrook, New Hampshire.
2010-07-01
... Guard District § 165.106 Security Zone: Seabrook Nuclear Power Plant, Seabrook, New Hampshire. (a... property boundary of Seabrook Nuclear Power Plant identified as follows: beginning at position 42°53′58″ N, 070°51′06″ W then running along the property boundaries of Seabrook Nuclear Power Plant to position...
The Green Launching Plan for New Hampshire's Environmental and Economic Future
Gittell, Ross
2010-01-01
Economic vitality and environmental protection have long been linked in New England, and will be again with efforts to address climate change in the region. There is an emerging body of literature to support the potential economic benefits of a so-called "green economy" in the region and the nation. In New Hampshire, economic studies of…
The Green Launching Plan for New Hampshire's Environmental and Economic Future
Gittell, Ross
2010-01-01
Economic vitality and environmental protection have long been linked in New England, and will be again with efforts to address climate change in the region. There is an emerging body of literature to support the potential economic benefits of a so-called "green economy" in the region and the nation. In New Hampshire, economic studies of both the…
75 FR 59787 - Notice of Final Federal Agency Actions on Proposed Highway in New Hampshire
2010-09-28
... Agency Actions on the Proposed Highway in New Hampshire'' in the Federal Register at 72 FR 30047-01 for... Protection and Repatriation Act (NAGPRA) . 6. Social and Economic: Civil Rights Act of 1964 [42 U.S.C. 2000(d..., Federal Actions to Address Environmental Justice in Minority Populations and Low Income Populations;...
76 FR 28022 - Hampshire Paper Company, Inc.; Notice of Availability of Environmental Assessment
2011-05-13
... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Hampshire Paper Company, Inc.; Notice of Availability of Environmental... strongly encourages electronic filing, documents may also be paper-filed. To paper-file, mail an...
Clintonit ähvardab kaotus ka New Hampshireþis
2008-01-01
Ilmunud ka: Postimees : na russkom jazõke 8. jaan. 2008, lk. 7. Arvamusküsitluste järgi juhtis demokraatide leeris USA presidendikandidaadiks pürgiv Barack Obama enne New Hampshireþi eelvalimisi oma pearivaali Hillary Clintoni ees 10% edumaaga
EPA Analysis Shows 2014 Decrease of Toxic Chemical Releases in New Hampshire
EPA’s most recent Toxic Release Inventory (TRI) data is now available for the reporting year of 2014. In New Hampshire, the reporting data show that overall releases of pollutants to the environment decreased since the previous reporting year (2013).
33 CFR 110.10 - Portsmouth Harbor, New Hampshire, north of Newcastle Island.
2010-07-01
..., north of Newcastle Island. 110.10 Section 110.10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT... Harbor, New Hampshire, north of Newcastle Island. From the northern most point of Goat Island to latitude... 213° to the shoreline of Newcastle Island, thence along the shoreline of Newcastle Island and...
2010-10-27
... also our policy on CCAAs (64 FR 32726; June 17, 1999). The CCAA that is the subject of this notice is a... Fish and Wildlife Service Endangered and Threatened Wildlife and Plants: New Hampshire Fish and Game... Game Department (NHFGD) has applied to the U.S. Fish and Wildlife Service (Service) for an...
ASSESSMENT OF MERCURY IN HYPOLIMNETIC LAKE SEDIMENTS OF VERMONT AND NEW HAMPSHIRE
The research is to characterize concentrations of total methylmercury in waters and surficial sediments of Vermont and New Hampshire lakes, and to relate these data to commonly measured water column chemical parameters and watershed-level physical attributes. The primary goal of...
Strengthening High School Teaching and Learning in New Hampshire's Competency-Based System
Haynes, Mariana
2013-01-01
For a century, most students have advanced from grade to grade based on the number of days they spend in class, but in New Hampshire, schools have moved away from "seat time" and toward "competency-based learning," which advances students when they have mastered course content. This report profiles how two high schools in New…
From Policy to Practice: How Competency-Based Education Is Evolving in New Hampshire
Freeland, Julia
2014-01-01
In 2005, New Hampshire abolished the Carnegie unit--the core unit around which schools typically measure credit hours. In its place, the state mandated that all high schools measure credit according to students' mastery of material, rather than time spent in class. This policy shift created the first-ever state-wide effort to create a…
2012-01-01
The present invention relates to a compact, reliable and low-cost vector velocimeter for example for determining velocities of particles suspended in a gas or fluid flow, or for determining velocity, displacement, rotation, or vibration of a solid surface, the vector velocimeter comprising a laser...... assembly for emission of a measurement beam for illumination of an object in a measurement volume with coherent light whereby a signal beam emanating from the object in the measurement volume is formed in response to illumination of the object by the measurement beam, a reference beam generator...... detector element signal when the fringe pattern formed by the interfering signal beam and reference beam moves across the first detector array; and a signal processor that is adapted for generation of a velocity signal corresponding to a first velocity component of movement of the object in the measurement...
2012-01-01
for generation of a reference beam, a detector system comprising a first detector arrangement arranged in such a way that the signal beam and the reference beam are incident upon the first detector arrangement with the reference beam propagating at an angle relative to a signal beam, and wherein the first......The present invention relates to a compact, reliable and low-cost vector velocimeter for example for determining velocities of particles suspended in a gas or fluid flow, or for determining velocity, displacement, rotation, or vibration of a solid surface, the vector velocimeter comprising a laser...... assembly for emission of a measurement beam for illumination of an object in a measurement volume with coherent light whereby a signal beam emanating from the object in the measurement volume is formed in response to illumination of the object by the measurement beam, a reference beam generator...
José Luiz de Sá
2005-03-01
Full Text Available O objetivo deste trabalho foi avaliar o efeito do fotoperíodo e da raça nas características de carcaça de cordeiros machos Hampshire Down e Santa Inês. Sete cordeiros Hampshire Down e sete Santa Inês foram submetidos a fotoperíodo de 12 horas luz x 12 horas escuro (curto e de 18 horas luz x 6 horas escuro (longo. Após o desmame, os cordeiros foram alojados em baias individuais de acordo com os tratamentos. Ao atingirem 31 kg de peso vivo, foram abatidos e a carcaça e os componentes não-constituintes da carcaça foram pesados. Cordeiros Santa Inês apresentaram peso de carcaça quente superior ao dos Hampshire e maior rendimento comercial. Cordeiros Santa Inês apresentaram maior peso de sangue, coração, pulmão, rins e baço. Já os cordeiros Hampshire Down apresentaram pesos de pele, patas e aparelho gastrintestinal cheio superiores aos do Santa Inês. Os cordeiros Santa Inês apresentaram maior largura de garupa e comprimento de perna do que os Hampshire Down. Os cordeiros Santa Inês apresentaram porcentagem de costela descoberta e baixos maior do que os Hampshire Down, com maior porcentagem de perna. A raça influencia mais as características de carcaça do que o fotoperíodo.The objective of this work was to evaluate the effect of photoperiod and breed on carcass characteristics. Seven Hampshire Down and seven Santa Inês ram lambs were assigned to two photoperiods: 12 hours light x 12 hours dark, or short photoperiod, and to 18 hours of light x 6 hours of dark, or long photoperiod. After weaning, the lambs were housed in individual stalls. The lambs were weighed weekly until slaughter weight of 31 kg. After slaughter, the carcass and the non-carcass components were weighed. Santa Inês lambs had higher hot carcass weight than Hampshire Down and also a higher commercial dressing percentage. Santa Inês lambs had higher blood, heart, lung, kidneys and spleen weight. The Hampshire Down lambs had higher skin, feet, full stomach
Coastal Resources Atlas: Long Island: HABITATS (Habitat Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for sensitive/rare coastal plants and submerged aquatic vegetation (SAV) for Long Island, New York. Vector...
Guam and the Northern Mariana Islands ESI: FISH (Fish Polygons)
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for reef, pelagic, benthic, and estuarine fish species in Guam and the Northern Mariana Islands. Vector...
National Oceanic and Atmospheric Administration, Department of Commerce — These data are an Integrated Ocean and Coastal Mapping (IOCM) Product of coastal New Hampshire. The images were acquired from a nominal altitude of 5,000 feet above...
U.S. Geological Survey, Department of the Interior — Binary point-cloud data for part of the Suncook River in New Hampshire were produced from remotely sensed, geographically referenced elevation measurements by the...
Final unioned polygons for the Deserado coal area, northwest Colorado (des*fing)
U.S. Geological Survey, Department of the Interior — These are shape files of final unioned polygon coverages used to calculate coal resources of the B and D coal zones, Lower White River coal field, Deserado...
Computing a single cell in the overlay of two simple polygons
Berg, M. de; Devillers, O.; Dobrindt, K.T.G.; Schwarzkopf, O.
1997-01-01
This note combines the lazy randomized incremental construction scheme with the technique of \\connectivity acceleration" to obtain an O ( n (log ? n ) 2 ) time randomized algorithm to compute a single face in the overlay oftwo simple polygons in the plane.
The Construction of the Dupin Cyclides in a Smectic A Polygonal Texture
Claire Meyer
2014-01-01
Full Text Available We report experimental observations with optical microscopy of the usual so-called polygonal texture. We have made simulations of the Dupin cyclides in one small region of the sample.
U.S. Geological Survey, Department of the Interior — This is a shapefile and the final unioned polygon coverage used to calculate coal resources of the Fruitland Formation, San Juan Basin coal assessment area, Colorado...
Two-point gauge invariant quark Green's functions with polygonal phase factor lines
Sazdjian, H
2013-01-01
Polygonal lines are used for the paths of the gluon field phase factors entering in the definition of gauge invariant quark Green's functions. This allows classification of the Green's functions according to the number of segments the polygonal lines contain. Functional relations are established between Green's functions with polygonal lines with different numbers of segments. An integrodifferential equation is obtained for the quark two-point Green's function with a path along a single straight line segment where the kernels are represented by a series of Wilson loop averages along polygonal contours. The equation is exactly and analytically solved in the case of two-dimensional QCD in the large-$N_c$ limit. The solution displays generation of an infinite number of dynamical quark masses accompanied with branch point singularities that are stronger than simple poles. An approximation scheme, based on the counting of functional derivatives of Wilson loops, is proposed for the resolution of the equation in fou...
U.S. Geological Survey, Department of the Interior — Reporting polygons were created to display and quantify overburden material above the Mahogany Zone, by PLSS section, in the Piceance Basin, Colorado as part of a...
SVANHAB -- Habitat polygons for the nearshore Point Arguello study area, South Vandenberg Reserve
U.S. Geological Survey, Department of the Interior — Benthic habitat polygon coverages have been created for marine reserve locations surrounding the Santa Barbara Basin. Diver, ROV and submersible video transects,...
AMCO Off-Site Air Monitoring Polygons, Oakland CA, 2017, US EPA Region 9
U.S. Environmental Protection Agency — This feature class was developed to support the AMCO Chemical Superfund Site air monitoring process and depicts a single polygon layer, Off-Site Air Monitors,...
Polygons Representing Sensitivity of Ground Water to Contamination in Lawrence County, SD
U.S. Geological Survey, Department of the Interior — This data set includes 956 polygons labeled with a sensitivity-unit code that represents the sensitivity of ground water to contamination in Lawrence County, SD....
NANPHAB -- Benthic Habitat polygons for North Anacapa Passage (UTM 10N, NAD83)
U.S. Geological Survey, Department of the Interior — Benthic habitat polygon coverages have been created for marine reserve locations surrounding the Santa Barbara Basin. Diver, ROV and submersible video transects,...
NANAHAB -- Habitat polygons for the nearshore North Anacapa Island, Channel Islands NMS
U.S. Geological Survey, Department of the Interior — Benthic habitat polygon coverages have been created for marine reserve locations surrounding the Santa Barbara Basin. Diver, ROV and submersible video transects,...
SMIGHAB -- Habitat polygons for the nearshore San Miguel Island, Channel Islands NMS
U.S. Geological Survey, Department of the Interior — Benthic habitat polygon coverages have been created for marine reserve locations surrounding the Santa Barbara Basin. Diver, ROV and submersible video transects,...
SECRUHAB -- Habitat polygons for Southeast Santa Cruz Island (UTM 10N, NAD83)
U.S. Geological Survey, Department of the Interior — Benthic habitat polygon coverages have been created for marine reserve locations surrounding the Santa Barbara Basin. Diver, ROV and submersible video transects,...
SANAHAB -- Benthic Habitat polygons for South Anacapa Island (UTM 10N, NAD83)
U.S. Geological Survey, Department of the Interior — Benthic habitat polygon coverages have been created for marine reserve locations surrounding the Santa Barbara Basin. Diver, ROV and submersible video transects,...
SANPHAB -- Habitat polygons for South Anacapa Passage (UTM 10N, NAD83)
U.S. Geological Survey, Department of the Interior — Benthic habitat polygon coverages have been created for marine reserve locations surrounding the Santa Barbara Basin. Diver, ROV and submersible video transects,...
NSGIC GIS Inventory (aka Ramona) — This Election Districts and Precincts dataset, was produced all or in part from Hardcopy Maps information as of 2000. It is described as 'Polygon shapefile in ESRI...
Coverage Polygons for DEMs of the North-Central California Coast (DEM_coverage_areas.shp)
U.S. Geological Survey, Department of the Interior — A GIS polygon shapefile outlining the extent of the 14 individual DEM sections that crompise the seamless, 2-meter resolution DEM for the open-coast region of the...
National Priorities List (NPL) Site Polygons, Region 9, 2012, US EPA Region 9
U.S. Environmental Protection Agency — NPL site POLYGON locations for the US EPA Region 9. NPL (National Priorities List) sites are hazardous waste sites that are eligible for extensive long-term cleanup...
SVANHAB -- Habitat polygons for the nearshore Point Arguello study area, South Vandenberg Reserve
U.S. Geological Survey, Department of the Interior — Benthic habitat polygon coverages have been created for marine reserve locations surrounding the Santa Barbara Basin. Diver, ROV and submersible video transects,...
SANAHAB -- Benthic Habitat polygons for South Anacapa Island (UTM 10N, NAD83)
U.S. Geological Survey, Department of the Interior — Benthic habitat polygon coverages have been created for marine reserve locations surrounding the Santa Barbara Basin. Diver, ROV and submersible video transects,...
SECRUHAB -- Habitat polygons for Southeast Santa Cruz Island (UTM 10N, NAD83)
U.S. Geological Survey, Department of the Interior — Benthic habitat polygon coverages have been created for marine reserve locations surrounding the Santa Barbara Basin. Diver, ROV and submersible video transects,...
NANAHAB -- Habitat polygons for the nearshore North Anacapa Island, Channel Islands NMS
U.S. Geological Survey, Department of the Interior — Benthic habitat polygon coverages have been created for marine reserve locations surrounding the Santa Barbara Basin. Diver, ROV and submersible video transects,...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains lines and polygons representing coastal hydrography used in the creation of the Environmental Sensitivity Index (ESI) for the Aleutian...
Coverage Polygons for DEMs of the North-Central California Coast (DEM_coverage_areas.shp)
U.S. Geological Survey, Department of the Interior — A GIS polygon shapefile outlining the extent of the 14 individual DEM sections that crompise the seamless, 2-meter resolution DEM for the open-coast region of the...
Computing a single cell in the overlay of two simple polygons
Berg, M. de; Devillers, O.; Dobrindt, K.T.G.; Schwarzkopf, O.
2001-01-01
This note combines the lazy randomized incremental construction scheme with the technique of \\connectivity acceleration" to obtain an O ( n (log ? n ) 2 ) time randomized algorithm to compute a single face in the overlay oftwo simple polygons in the plane.
Sun Qiliang; Wu Shiguo; Yao Genshun; LI Fuliang
2009-01-01
Based on high-resolution 3D seismic data，we document the polygonal faults within the Miocene Meishan (梅山) Formation and Huangliu (黄流) Formation of the Qiongdongnan (琼东南)basin，northern South China Sea.Within the seismic section and time coherent slice，densely distributed extensional faults with small throw and polygonal shape were identified in map view.The orientation of the polygonal faults is almost isotropic，indicating a non-tectonic origin.The deformation is clearly layer-bounded，with horizontal extension of 11.2% to 16%，and 13.2% on average.The distribution of polygonal faults shows a negative correlation with that of gas chimneys.The development of polygonal faults may be triggered by over-pressure pore fluid which is restricted in the fine-grained sediments of bathyal facies when the sediments is compacted by the burden above.The polygonal faults developed to balance the volumetric contraction and restricted extension.The product of hydrocarbon in the Meishan Formation may have contributed to the development of the polygonal faults.In the study area，it was thought that the petroleum system of the Neogene post-rift sequence is disadvantageous because of poor migration pathway.However，the discovery of polygonal faults In the Miocene strata，which may play an important role on the fluid migra-tion，may change this view.A new model of the petroleum system for the study area is proposed.
Isotopic insights into methane production, oxidation, and emissions in Arctic polygon tundra.
Vaughn, Lydia J S; Conrad, Mark E; Bill, Markus; Torn, Margaret S
2016-10-01
Arctic wetlands are currently net sources of atmospheric CH4 . Due to their complex biogeochemical controls and high spatial and temporal variability, current net CH4 emissions and gross CH4 processes have been difficult to quantify, and their predicted responses to climate change remain uncertain. We investigated CH4 production, oxidation, and surface emissions in Arctic polygon tundra, across a wet-to-dry permafrost degradation gradient from low-centered (intact) to flat- and high-centered (degraded) polygons. From 3 microtopographic positions (polygon centers, rims, and troughs) along the permafrost degradation gradient, we measured surface CH4 and CO2 fluxes, concentrations and stable isotope compositions of CH4 and DIC at three depths in the soil, and soil moisture and temperature. More degraded sites had lower CH4 emissions, a different primary methanogenic pathway, and greater CH4 oxidation than did intact permafrost sites, to a greater degree than soil moisture or temperature could explain. Surface CH4 flux decreased from 64 nmol m(-2) s(-1) in intact polygons to 7 nmol m(-2) s(-1) in degraded polygons, and stable isotope signatures of CH4 and DIC showed that acetate cleavage dominated CH4 production in low-centered polygons, while CO2 reduction was the primary pathway in degraded polygons. We see evidence that differences in water flow and vegetation between intact and degraded polygons contributed to these observations. In contrast to many previous studies, these findings document a mechanism whereby permafrost degradation can lead to local decreases in tundra CH4 emissions.
From Polygon Wilson Loops to Spin Chains and Back
Sever, Amit; Wang, Tianheng
2012-01-01
Null Polygon Wilson Loops (WL) in N=4 SYM can be computed using the Operator Product Expansion in terms of a transition amplitude on top of a color flux tube (FT). That picture is valid at any value of the 't Hooft coupling. So far it has been efficiently used at weak coupling (WC) in cases where only a single particle is flowing. At any finite value of the coupling however, an infinite number of particles are flowing on top of the color FT. A major open problem in this approach was how to deal with generic multi-particle states at WC. In this paper we study the propagation of any number of FT excitations at WC. We do this by first mapping the WL into a sum of two point functions of local operators. This map allows us to translate the integrability techniques developed for the spectrum problem back to the WL. E.g., the FT Hamiltonian can be represented as a simple kernel acting on the loop. Having an explicit representation for the FT Hamiltonian allows us to treat any number of particles on an equal footing....
Polygon cluster pattern recognition based on new visual distance
Shuai, Yun; Shuai, Haiyan; Ni, Lin
2007-06-01
The pattern recognition of polygon clusters is a most attention-getting problem in spatial data mining. The paper carries through a research on this problem, based on spatial cognition principle and visual recognition Gestalt principle combining with spatial clustering method, and creates two innovations: First, the paper carries through a great improvement to the concept---"visual distance". In the definition of this concept, not only are Euclid's Distance, orientation difference and dimension discrepancy comprehensively thought out, but also is "similarity degree of object shape" crucially considered. In the calculation of "visual distance", the distance calculation model is built using Delaunay Triangulation geometrical structure. Second, the research adopts spatial clustering analysis based on MST Tree. In the design of pruning algorithm, the study initiates data automatism delamination mechanism and introduces Simulated Annealing Optimization Algorithm. This study provides a new research thread for GIS development, namely, GIS is an intersection principle, whose research method should be open and diverse. Any mature technology of other relative principles can be introduced into the study of GIS, but, they need to be improved on technical measures according to the principles of GIS as "spatial cognition science". Only to do this, can GIS develop forward on a higher and stronger plane.
The linking number and the writhe of uniform random walks and polygons in confined spaces
Panagiotou, E.; Millett, K. C.; Lambropoulou, S.
2010-01-01
Random walks and polygons are used to model polymers. In this paper we consider the extension of the writhe, self-linking number and linking number to open chains. We then study the average writhe, self-linking and linking number of random walks and polygons over the space of configurations as a function of their length. We show that the mean squared linking number, the mean squared writhe and the mean squared self-linking number of oriented uniform random walks or polygons of length n, in a convex confined space, are of the form O(n2). Moreover, for a fixed simple closed curve in a convex confined space, we prove that the mean absolute value of the linking number between this curve and a uniform random walk or polygon of n edges is of the form O(\\sqrt{n}) . Our numerical studies confirm those results. They also indicate that the mean absolute linking number between any two oriented uniform random walks or polygons, of n edges each, is of the form O(n). Equilateral random walks and polygons are used to model polymers in θ-conditions. We use numerical simulations to investigate how the self-linking and linking number of equilateral random walks scale with their length.
Co-evolution of polygonal and scalloped terrains, southwestern Utopia Planitia, Mars
Haltigin, T. W.; Pollard, W. H.; Dutilleul, P.; Osinski, G. R.; Koponen, L.
2014-02-01
Thermal contraction crack polygons and scalloped depressions, two of the most common landforms found in Utopia Planitia, Mars, have previously been linked to the presence of ice-rich deposits in the subsurface. Although the formation and evolution of these features individually are relatively well understood, little to no effort has been directed towards elucidating possible interactions that occur between them during their development. Thus, the overarching goal of this research was to investigate if there is an evolutionary link between polygonal and scalloped terrains by correlating metrics representing polygon and scallop maturity. A variety of statistical analyses were performed using HiRISE and MOLA datasets to quantify interactions between four sets of polygonal and scalloped terrains. Our results demonstrate the existence of a negative relationship between polygonal subdivision and surface elevation, indicating that polygon networks become more ‘evolved’ as the surface subsides. These results suggest that the permafrost landscape in Utopia Planitia may once have been extremely ice-rich, and that multiple geomorphic processes may be responsible for its evolution. Ultimately, this work demonstrates that landscape reconstruction is more complete when a system approach is followed, quantifying interactions between landforms as opposed to examining an individual landform in isolation.
Buczkowski, Debra L.; Seelos, Kim D.; Cooke, Michele L.
2012-08-01
Large-scale fracture systems surrounding the Utopia basin include giant polygons and circular graben. Data covering the northern Utopia basin now allow high-resolution mapping of these features in all regions of the basin. Giant polygons to the north and south of the basin are different in both size and morphology, leading to the polygon classifications (1) S-style, (2) subdued S-style, (3) northern S-style and (4) N-style. Also, ten circular graben have been identified to the north of the Utopia basin. These have generally larger diameters than southern circular graben, and their fracture morphology is similar to N-style giant polygons. As with southern circular graben, the surface relief of the depression inside the northern circular graben scales directly with diameter. However, northern circular graben have less steep trend slopes, larger average diameters and greater ring spacing compared to southern circular graben of the same diameter and similar distance to the center of the Utopia basin. Both the giant polygons and circular graben of Utopia Planitia are consistent with formation by volumetric compaction of a fine-grained sedimentary material covering an uneven buried surface. Giant polygon size variations can be explained by the material being wet to the south but frozen or partially frozen to the north, while differences between northern and southern circular graben may be attributed to changes in cover thickness. Differences in fracture morphology can be explained by subsequent alteration of the northern troughs due to polar processes.
Horikis, Theodoros P
2016-01-01
Families of soliton pairs, namely vector solitons, are found within the context of a coupled nonlocal nonlinear Schrodinger system of equations, as appropriate for modeling beam propagation in nematic liquid crystals. In the focusing case, bright soliton pairs have been found to exist provided their amplitudes satisfy a specific condition. In our analytical approach, focused on the defocusing regime, we rely on a multiscale expansion methods, which reveals the existence of dark-dark and antidark-antidark solitons, obeying an effective Korteweg-de Vries equation, as well as dark-bright solitons, obeying an effective Mel'nikov system. These pairs are discriminated by the sign of a constant that links all physical parameters of the system to the amplitude of the stable continuous wave solutions, and, much like the focusing case, the solitons' amplitudes are linked leading to mutual guiding.
2016-11-01
Petrographic Analysis of Portland Cement Concrete Cores from Pease Air National Guard Base, New Hampshire E n g in e e r R e s e a rc h a n d...id, age of the concrete being evaluated and tests performed...4 3 Preface This study was conducted in support of the Air Force Civil Engineer Center (AFCEC) to assess concrete obtained from Pease
Integrated metagenomics and field measurements of polygon features at the NGEE-Arctic Barrow site
Tas, N.; Wu, Y.; Smith, L. J.; Ulrich, C.; Kneafsey, T. J.; Torn, M. S.; Hubbard, S. S.; Wullschleger, S. D.; Jansson, J.
2013-12-01
Arctic soils contain an estimated 12-42% of terrestrial carbon, most of which is sequestered in permafrost. High latitudes have experienced the greatest regional warming in recent decades and observations suggest that permafrost degradation is now commonly observed in the region. With increasing global temperatures, permafrost soils are becoming a potential source of greenhouse gas (GHG) emissions. Because of widespread permafrost thaw much of the soil organic matter may be available for rapid mineralization by microorganisms in the soil. Yet little is known about the vulnerability of permafrost and the potential response of soil microorganisms to availability of new carbon sources. On the Alaskan North Slope the collapse and rise of soil due to formation of ice wedges and permafrost thaw create distinct features called polygons. As part of the U.S. Department of Energy (DOE) Next Generation Ecosystem Experiment (NGEE) in the Arctic, we aimed to determine the distribution of microbial populations across a range of polygon features and to correlate the microbial data to GHG flux data. To determine the microbial community distribution and metabolic potential, we collected seasonally thawed active layer soil samples along two polygon transects (Site 0 and AB), including high-centered, transitional and low-centered polygons. Illumina HiSeq technology was used to sequence 16SrRNA genes and metagenomes from these active layer soils. The sequence data was correlated to GHG flux measurements and to environmental data from the site, including geophysical and geochemical soil characteristics. Both the microbial communities and the flux measurements varied along the polygon transect. Each polygon had a distinct microbial community structure; however, these microbial communities shared many metabolic capabilities. For example, many genes involved in degradation of chitin could be found all three polygons. Functional genes involved in methanogenesis and CH4-flux measurements
Total Harmonic Distortion of Dodecagonal Space Vector Modulation
Babita Nanda
2014-05-01
Full Text Available Space vector modulation technique is one of the best PWM technique which has been implemented to the Multilevel inverter circuit to get the purely sinusoidal cuurent .This is a important algorithm which is implemented in open wind induction motor.This type of I.M has great impact on Electric Drive system. SVM is nothing but the technique of switching algorithm .The Hexagonal space vector modulation has been implemented before , but elimination of higher order harmonics are not possible. Torque pulsation arises. Speed control of Induction motor was not smooth .so Dodecagonal (12 structure developed. A 12 side polygonal space vector structure is meant for eliminating (6n±1 harmonics in the phase current waveform throughout the modulating range. A high resolution of PWM technique is proposed involving multiple 12 sided polygonal (Dodecagonal structure that can generate highly sinusoidal voltage at a reduced switching frequency. In this paper different values of frequencies have been taken for harmonic analysis. SVM method features a higher level of dc-bus voltage utilization compared to the conventional PWM.
The Fecal Microbiota Composition of Boar Duroc, Yorkshire, Landrace and Hampshire Pigs.
Xiao, Yingping; Li, Kaifeng; Xiang, Yun; Zhou, Weidong; Gui, Guohong; Yang, Hua
2017-02-23
To investigate the effect of host genetics on gut microbial diversity, we performed a structural survey of the fecal microbiota of four purebred boar pig lines: Duroc, Landrace, Hampshire and Yorkshire. The V3-V4 regions of the 16S rRNA genes were amplified and sequenced. A total of 783 OTUs were shared by all breeds, whereas other OTUs were breed-specific. Firmicutes and Bacteroidetes dominated the majority of the fecal microbiota; Clostridia, Bacilli and Bacteroidia were the major classes. Nine predominant genera were observed in all breeds and eight of them can produce short-chain fatty acids (SCFAs). Some bacteria can secrete cellulase to aid fiber digestion by the host. Butyric, isobutyric, valeric and isovaleric acid levels were highest in Landrace pigs, whereas acetic and propionic acid were highest in the Hampshire breed. Heatmap was used to revealed breed-specific bacteria. Principal coordinate analysis (PCoA) of fecal bacteria revealed that the Landrace and Yorkshire breeds had high similarity and were clearly separated from the Duroc and Hampshire breeds. Overall, this study is the first time to compare the fecal microbiomes of four breeds of boar pig by high-throughput sequencing and to use Spearman's rank correlation to analyze competition and cooperation among the core bacteria.
The New Hampshire retail competition pilot program and the role of green marketing
Holt, E.A. [Ed Holt and Associates, Inc. (United States); Fang, J.M. [National Renewable Energy Lab., Golden, CO (United States)
1997-11-01
Most states in the US are involved in electric industry restructuring, from considering the pros and cons in regulatory dockets to implementing legislative mandates for full restructuring and retail access for all consumers. Several states and utilities have initiated pilot programs in which multiple suppliers or service providers may compete for business and some utility customers can choose among competing suppliers. The State of New Hampshire has been experimenting with a pilot program, mandated by the State Legislature in 1995 and implemented by the New Hampshire Public Utilities Commission (NHPUC), before it implements full retail access. Green marketing, an attempt to characterize the supplier or service provider as environmentally friendly without referring to the energy resource used to generate electricity, was used by several suppliers or service providers to attract customers. This appeal to environmental consumerism was moderately successful, but it raised a number of consumer protection and public policy issues. This issue brief examines the marketing methods used in New Hampshire and explores what green marketing might mean for the development of renewable energy generation. It also addresses the issues raised and their implications.
Study on High-Speed Magnitude Approximation for Complex Vectors
陈建春; 杨万海; 许少英
2003-01-01
High-speed magnitude approximation algorithms for complex vectors are discussed intensively. The performance and the convergence speed of these approximation algorithms are analyzed. For the polygon fitting algorithms, the approximation formula under the least mean square error criterion is derived. For the iterative algorithms, a modified CORDIC (coordinate rotation digital computer) algorithm is developed. This modified CORDIC algorithm is proved to be with a maximum relative error about one half that of the original CORDIC algorithm. Finally, the effects of the finite register length on these algorithms are also concerned, which shows that 9 to 12-bit coefficients are sufficient for practical applications.
Fox, Christopher; Romeijn, H Edwin; Dempsey, James F
2006-05-01
We present work on combining three algorithms to improve ray-tracing efficiency in radiation therapy dose computation. The three algorithms include: An improved point-in-polygon algorithm, incremental voxel ray tracing algorithm, and stereographic projection of beamlets for voxel truncation. The point-in-polygon and incremental voxel ray-tracing algorithms have been used in computer graphics and nuclear medicine applications while the stereographic projection algorithm was developed by our group. These algorithms demonstrate significant improvements over the current standard algorithms in peer reviewed literature, i.e., the polygon and voxel ray-tracing algorithms of Siddon for voxel classification (point-in-polygon testing) and dose computation, respectively, and radius testing for voxel truncation. The presented polygon ray-tracing technique was tested on 10 intensity modulated radiation therapy (IMRT) treatment planning cases that required the classification of between 0.58 and 2.0 million voxels on a 2.5 mm isotropic dose grid into 1-4 targets and 5-14 structures represented as extruded polygons (a.k.a. Siddon prisms). Incremental voxel ray tracing and voxel truncation employing virtual stereographic projection was tested on the same IMRT treatment planning cases where voxel dose was required for 230-2400 beamlets using a finite-size pencil-beam algorithm. Between a 100 and 360 fold cpu time improvement over Siddon's method was observed for the polygon ray-tracing algorithm to perform classification of voxels for target and structure membership. Between a 2.6 and 3.1 fold reduction in cpu time over current algorithms was found for the implementation of incremental ray tracing. Additionally, voxel truncation via stereographic projection was observed to be 11-25 times faster than the radial-testing beamlet extent approach and was further improved 1.7-2.0 fold through point-classification using the method of translation over the cross product technique.
Kumar, Jitendra; Collier, Nathan; Bisht, Gautam; Mills, Richard T.; Thornton, Peter E.; Iversen, Colleen M.; Romanovsky, Vladimir
2016-09-01
Vast carbon stocks stored in permafrost soils of Arctic tundra are under risk of release to the atmosphere under warming climate scenarios. Ice-wedge polygons in the low-gradient polygonal tundra create a complex mosaic of microtopographic features. This microtopography plays a critical role in regulating the fine-scale variability in thermal and hydrological regimes in the polygonal tundra landscape underlain by continuous permafrost. Modeling of thermal regimes of this sensitive ecosystem is essential for understanding the landscape behavior under the current as well as changing climate. We present here an end-to-end effort for high-resolution numerical modeling of thermal hydrology at real-world field sites, utilizing the best available data to characterize and parameterize the models. We develop approaches to model the thermal hydrology of polygonal tundra and apply them at four study sites near Barrow, Alaska, spanning across low to transitional to high-centered polygons, representing a broad polygonal tundra landscape. A multiphase subsurface thermal hydrology model (PFLOTRAN) was developed and applied to study the thermal regimes at four sites. Using a high-resolution lidar digital elevation model (DEM), microtopographic features of the landscape were characterized and represented in the high-resolution model mesh. The best available soil data from field observations and literature were utilized to represent the complex heterogeneous subsurface in the numerical model. Simulation results demonstrate the ability of the developed modeling approach to capture - without recourse to model calibration - several aspects of the complex thermal regimes across the sites, and provide insights into the critical role of polygonal tundra microtopography in regulating the thermal dynamics of the carbon-rich permafrost soils. Areas of significant disagreement between model results and observations highlight the importance of field-based observations of soil thermal and
Meter-scale polygons on 67P/Churyumov-Gerasimenko as evidences of near subsurface water ice
Auger, A.-T.; El-Maarry, M. R.; Groussin, O.; Capanna, C.; Jorda, L.; Bouley, S.; Davidsson, B.; Deller, J.; Güttler, C.; Hofmann, M.; Höfner, S.; Lamy, P. L.; Lazzarin, M.; Marchi, S.; Thomas, N.; Vincent, J.-B.; Sierks, H.
2015-10-01
Since August 2014, high spatial resolution images of the nucleus of 67P/Churyumov-Gerasimenko have been acquired by the OSIRIS camera on board the Rosetta spacecraft, enabling to identify meter-scale features on the surface. Among them, we identify polygons with a size from 2 to 20 meters. We define the polygons on 67P as high-centered thermal contraction polygons, which further evolve through preferential sublimation along the cracks. This kind of polygons are known on Earth and Mars as evidences of permanent water ice table in the near subsurface [1,2,3].
Heil, Martin; Jansen-Osmann, Petra
2008-05-01
Sex differences in mental rotation were investigated as a function of stimulus complexity with a sample size of N = 72. Replicating earlier findings with polygons, mental rotation was faster for males than for females, and reaction time increased with more complex polygons. Additionally, sex differences increased for complex polygons. Most importantly, however, mental rotation speed decreased with increasing complexity for women but did not change for men. Thus, the sex effects reflect a difference in strategy, with women mentally rotating the polygons in an analytic, piecemeal fashion and men using a holistic mode of mental rotation.
Louisiana Geographic Information Center — This data set contains polygons representing the Environmental Sensitivity Index (ESI) classification of coastal Louisiana. The ESI is a classification and ranking...
Bennett, Derek S.; Lyons, John B.; Wittkop, Chad A.; Dicken, Connie L.
2006-01-01
The New Hampshire Geological Survey collects data and performs research on the land, mineral, and water resources of the State, and disseminates the findings of such research to the public through maps, reports, and other publications. The Bedrock Geologic Map of New Hampshire, by John B. Lyons, Wallace A. Bothner, Robert H. Moench, and James B. Thompson, was published in paper format by the U.S. Geological Survey (USGS) in 1997. The online version of this CD contains digital datasets of the State map that are intended to assist the professional geologist, land-use planners, water resource professionals, and engineers and to inform the interested layperson. In addition to the bedrock geology, the datasets include geopolitical and hydrologic information, such as political boundaries, quadrangle boundaries, hydrologic units, and water-well data. A more thorough explanation for each of these datasets may be found in the accompanying metadata files. The data are spatially referenced and may be used in a geographic information system (GIS). ArcExplorer, the Environmental Systems Research Institute's (ESRI) free GIS data viewer, is available at http://www.esri.com/software/arcexplorer. ArcExplorer provides basic functions that are needed to harness the power and versatility of the spatial datasets. Additional information on the viewer and other ESRI products may be found on the ArcExplorer website. Although extensive review and revisions of the data have been performed by the USGS and the New Hampshire Geological Survey, these data represent interpretations made by professional geologists using the best available data, and are intended to provide general geologic information. Use of these data at scales larger than 1:250,000 will not provide greater accuracy. The data are not intended to replace site-specific or specific-use investigations. The U.S. Geological Survey, New Hampshire Geological Survey, and State of New Hampshire make no representation or warranty
Development of polygonal-surface version of ICRP reference phantoms: Lymphatic node modeling
Thang, Ngyen Tat; Yeom, Yeon Soo; Han, Min Cheol; Kim, Chan Hyeong [Hanyang University, Seoul (Korea, Republic of)
2014-04-15
Among radiosensitive organs/tissues considered in ICRP Publication 103, lymphatic nodes are many small size tissues and widely distributed in the ICRP reference phantoms. It is difficult to directly convert lymphatic nodes of ICRP reference voxel phantoms to polygonal surfaces. Furthermore, in the ICRP reference phantoms lymphatic nodes were manually drawn only in six lymphatic node regions and the reference number of lymphatic nodes reported in ICRP Publication 89 was not considered. To address aforementioned limitations, the present study developed a new lymphatic node modeling method for the polygonal-surface version of ICRP reference phantoms. By using the developed method, lymphatic nodes were modelled in the preliminary version of ICRP male polygonal-surface phantom. Then, lymphatic node dose values were calculated and compared with those of the ICRP reference male voxel phantom to validate the developed modeling method. The present study developed the new lymphatic node modeling method and successfully modeled lymphatic nodes in the preliminary version of the ICRP male polygonal-surface phantom. From the results, it was demonstrated that the developed modeling method can be used to model lymphatic nodes in polygonal-surface version of ICRP reference phantoms.
Flow rate of polygonal grains through a bottleneck: Interplay between shape and size
Ezequiel Goldberg
2015-11-01
Full Text Available We report two-dimensional simulations of circular and polygonal grains passing through an aperture at the bottom of a silo. The mass flow rate for regular polygons is lower than for disks\\red{,} as observed by other authors. We show that both the exit velocity of the grains and the packing fraction are lower for polygons, which leads to the reduced flow rate. We point out the importance of the criteria used to define when two objects of different shape are considered to be of the same size. Depending on this criteria, the mass flow rate may vary significantly for some polygons. Moreover, the particle flow rate is non-trivially related to a combination of mass flow rate, particle shape and particle size. For some polygons, the particle flow rate may be lower or higher than that of the corresponding disks depending on the size comparison criteria. Received: 18 May 2015, Accepted: 30 October 2015; Edited by: F. Melo; Reviewed by: J.-N. Roux, Universite Parsi Est, Laboratoire Navier, Champs-sur-Marne, France; DOI: http://dx.doi.org/10.4279/PIP.070016 Cite as: E Goldberg, C M Carlevaro, L A Pugnaloni, Papers in Physics 7, 070016 (2015
Steffen, W.; Koning, N.
2017-07-01
We demonstrate the potential for research and outreach of mixed polygon and hydrodynamic modeling and multi-waveband rendering in the interactive 3-D astrophysical virtual laboratory Shape. In 3-D special effects and animation software for the mass media, computer graphics techniques that mix polygon and numerical hydrodynamics have become common place. In astrophysics, however, interactive modeling with polygon structures has only become available with the software Shape. Numerical hydrodynamic simulations and their visualization are usually separate, while in Shape it is integrated with the polygon modeling approach that requires no programming by the user. With two generic examples, we demonstrate that research and outreach modeling can be achieved with techniques similar to those used in the media industry with the added capability for physical rendering at any wavelength band, yielding more realistic radiation modeling. Furthermore, we show how the hydrodynamics and the polygon mesh modeling can be mixed to achieve results that are superior to those obtained using either one of these modeling techniques alone.
Robust polygon recognition method with similarity invariants applied to star identification
Hernández, E. Antonio; Alonso, Miguel A.; Chávez, Edgar; Covarrubias, David H.; Conte, Roberto
2017-02-01
In the star identification process the goal is to recognize a star by using the celestial bodies in its vicinity as context. An additional requirement is to avoid having to perform an exhaustive scan of the star database. In this paper we present a novel approach to star identification using similarity invariants. More specifically, the proposed algorithm defines a polygon for each star, using the neighboring celestial bodies in the field of view as vertices. The mapping is insensitive to similarity transformation; that is, the image of the polygon under the transformation is not affected by rotation, scaling or translations. Each polygon is associated with an essentially unique complex number. We perform an exhaustive experimental validation of the proposed algorithm using synthetic data generated from the star catalog with uniformly-distributed positional noise introduced to each star. The star identification method that we present is proven to be robust, achieving a recognition rate of 99.68% when noise levels of up to ± 424 μ radians are introduced to the location of the stars. In our tests the proposed algorithm proves that if a polygon match is found, it always corresponds to the star under analysis; no mismatches are found. In its present form our method cannot identify polygons in cases where there exist missing or false stars in the analyzed images, in those situations it only indicates that no match was found.
Oehler, Dorothy Z.; Mangold, Nicolas; Hallet, Bernard; Fairén, Alberto G.; Deit, Laetitia Le; Williams, Amy J.; Sletten, Ronald S.; Martínez-Frías, Jesús
2016-10-01
Decameter-scale polygons are extensively developed in the Bedded Fractured (BF) Unit of the lower Peace Vallis fan. The polygons occur in a likely extension of the Gillespie Lake Member, north of Yellowknife Bay, the section first drilled by the Mars Science Laboratory (MSL) mission. We examine hypotheses for the origin of these polygons to provide insight into the history of Gale crater. The polygons are ∼4-30 m across, square to rectangular, and defined by ∼0.5-4 m wide, generally straight troughs with orthogonal intersections. Polygon networks are typically oriented-orthogonal systems, with occasional nearly circular patterns, hundreds of meters across. Potential origins include cooling of lava, and for sedimentary units, syneresis, unloading, weathering, desiccation, impact processes, and cold-climate thermal contraction. Cold-climate thermal contraction is the hypothesis most consistent with the sedimentary nature of the BF Unit and the polygon morphology, geometry, networks, and apparent restriction to the coarse-grained Gillespie Lake Member. A periglacial setting further provides the best analogs for the circular networks and is consistent with geologic context and MSL data. Most of the decametric polygons appear to be ancient. They are confined to the Hesperian BF Unit, and only a few of their bounding fractures extend into younger or recently exposed units. In this regard, they differ from the majority of proposed thermal-contraction polygons on Mars, as those are generally thought to be young features, and, accordingly, the history of formation, preservation and reactivation of the decametric polygons is likely to be more complex than that of any proposed young polygons on Mars. The decametric polygons in the BF Unit may represent landforms developed in a cold but still comparatively wet interlude between a clement early Mars and the much drier and colder planet of today.
Development of skeleton model for use in polygonal-mesh-type ICRP reference phantoms
Nguyen, Thang Tat; Yeom, Yeon Soo; Han, Min Cheol; Wang, Zhao Jun; Kim, Han Sung; Kim, Chan Hyeong [Dept.of Nuclear Engineering, Hanyang University, Seoul (Korea, Republic of)
2015-04-15
In order to overcome the limitations, we are currently developing the polygonal-mesh versions of the ICRP reference phantoms by converting the ICRP reference voxel phantoms to polygonal-mesh format. As a part of the ICRP reference phantom conversion project, the present study completed the conversion of skeleton, which is a very complex framework of the body, while addressing some critical problems of the skeleton of the ICRP reference voxel phantoms. The converted skeleton models were also evaluated by comparing dose values of RBM and endosteum with those of the ICRP reference voxel phantoms. As a part of the ICRP reference phantom conversion project, the present study successfully completed skeleton conversion of the ICRP reference adult male and female phantoms to polygonal-mesh format. A comprehensive study of dosimetric effects by the skeleton conversion will be performed in the future.
Asymptotic behavior of large polygonal Wilson loops in confining gauge theories
Pobylitsa, P V
2016-01-01
In the framework of effective string theory (EST), the asymptotic behavior of a large Wilson loop in confining gauge theories can be expressed via Laplace determinant with Dirichlet boundary condition on the Wilson contour. For a general polygonal region, Laplace determinant can be computed using the conformal anomaly and Schwarz-Christoffel transformation. One can construct ratios of polygonal Wilson loops whose large-size limit can be expressed via computable Laplace determinants and is independent of the (confining) gauge group. These ratios are computed for hexagon polygons both in EST and by Monte Carlo (MC) lattice simulations for the tree-dimensional lattice Z2 gauge theory (dual to Ising model) near its critical point. For large hexagon Wilson loops a perfect agreement is observed between the asymptotic EST expressions and the lattice MC results.
Lv, Jun; Tang, Liang; Li, Wenbo; Liu, Lei; Zhang, Hongwu
2016-05-01
This paper mainly focuses on the fast and efficient design method for plant bioinspired fluidic cellular materials and structures composed of polygonal motor cells. Here we developed a novel structural optimization method with arbitrary polygonal coarse-grid elements based on multiscale finite element frameworks. The fluidic cellular structures are meshed with irregular polygonal coarse-grid elements according to their natural size and the shape of the imbedded motor cells. The multiscale base functions of solid displacement and hydraulic pressure are then constructed to bring the small-scale information of the irregular motor cells to the large-scale simulations on the polygonal coarse-grid elements. On this basis, a new topology optimization method based on the resulting polygonal coarse-grid elements is proposed to determine the optimal distributions or number of motor cells in the smart cellular structures. Three types of optimization problems are solved according to the usages of the fluidic cellular structures. Firstly, the proposed optimization method is utilized to minimize the system compliance of the load-bearing fluidic cellular structures. Second, the method is further extended to design biomimetic compliant actuators of the fluidic cellular materials due to the fact that non-uniform volume expansions of fluid in the cells can induce elastic action. Third, the optimization problem focuses on the weight minimization of the cellular structure under the constraints for the compliance of the whole system. Several representative examples are investigated to validate the effectiveness of the proposed polygon-based topology optimization method of the smart materials.
Evapotranspiration across plant types and geomorphological units in polygonal Arctic tundra
Raz-Yaseef, Naama; Young-Robertson, Jessica; Rahn, Thom; Sloan, Victoria; Newman, Brent; Wilson, Cathy; Wullschleger, Stan D.; Torn, Margaret S.
2017-10-01
Coastal tundra ecosystems are relatively flat, and yet display large spatial variability in ecosystem traits. The microtopographical differences in polygonal geomorphology produce heterogeneity in permafrost depth, soil temperature, soil moisture, soil geochemistry, and plant distribution. Few measurements have been made, however, of how water fluxes vary across polygonal tundra plant types, limiting our ability to understand and model these ecosystems. Our objective was to investigate how plant distribution and geomorphological location affect actual evapotranspiration (ET). These effects are especially critical in light of the rapid change polygonal tundra systems are experiencing with Arctic warming. At a field site near Barrow, Alaska, USA, we investigated the relationships between ET and plant cover in 2014 and 2015. ET was measured at a range of spatial and temporal scales using: (1) An eddy covariance flux tower for continuous landscape-scale monitoring; (2) An automated clear surface chamber over dry vegetation in a fixed location for continuous plot-scale monitoring; and (3) Manual measurements with a clear portable chamber in approximately 60 locations across the landscape. We found that variation in environmental conditions and plant community composition, driven by microtopographical features, has significant influence on ET. Among plant types, ET from moss-covered and inundated areas was more than twice that from other plant types. ET from troughs and low polygonal centers was significantly higher than from high polygonal centers. ET varied seasonally, with peak fluxes of 0.14 mm h-1 in July. Despite 24 hours of daylight in summer, diurnal fluctuations in incoming solar radiation and plant processes produced a diurnal cycle in ET. Combining the patterns we observed with projections for the impact of permafrost degradation on polygonal structure suggests that microtopographic changes associated with permafrost thaw have the potential to alter tundra
Luís F Seoane
2015-04-01
Full Text Available We provide a proof of concept for an EEG-based reconstruction of a visual image which is on a user's mind. Our approach is based on the Rapid Serial Visual Presentation (RSVP of polygon primitives and Brain-Computer Interface (BCI technology. In an experimental setup, subjects were presented bursts of polygons: some of them contributed to building a target image (because they matched the shape and/or color of the target while some of them did not. The presentation of the contributing polygons triggered attention-related EEG patterns. These Event Related Potentials (ERPs could be determined using BCI classification and could be matched to the stimuli that elicited them. These stimuli (i.e. the ERP-correlated polygons were accumulated in the display until a satisfactory reconstruction of the target image was reached. As more polygons were accumulated, finer visual details were attained resulting in more challenging classification tasks. In our experiments, we observe an average classification accuracy of around 75%. An in-depth investigation suggests that many of the misclassifications were not misinterpretations of the BCI concerning the users' intent, but rather caused by ambiguous polygons that could contribute to reconstruct several different images. When we put our BCI-image reconstruction in perspective with other RSVP BCI paradigms, there is large room for improvement both in speed and accuracy. These results invite us to be optimistic. They open a plethora of possibilities to explore non-invasive BCIs for image reconstruction both in healthy and impaired subjects and, accordingly, suggest interesting recreational and clinical applications.
Polygonal approximation and scale-space analysis of closed digital curves
Ray, Kumar S
2013-01-01
This book covers the most important topics in the area of pattern recognition, object recognition, computer vision, robot vision, medical computing, computational geometry, and bioinformatics systems. Students and researchers will find a comprehensive treatment of polygonal approximation and its real life applications. The book not only explains the theoretical aspects but also presents applications with detailed design parameters. The systematic development of the concept of polygonal approximation of digital curves and its scale-space analysis are useful and attractive to scholars in many fi