9,742 research outputs found

    Combinatorial Designs with Two Singular Values I. Uniform Multiplicative Designs

    Get PDF
    In this and a sequel paper [10] we study combinatorial designs whose incidence matrix has two distinct singular values.These generalize 2-(v, k, É) designs, and include partial geometric designs and uniform multiplicative designs.Here we study the latter, which are precisely the nonsingular designs.We classify all such designs with smallest singular value at most, generalize the Bruck-Ryser-Chowla conditions, and enumerate, partly by computer, all uniform multiplicative designs on at most 30 points.combinatorics;matrices;singularities

    Combinatorial Designs with Two Singular Values II. Partial Geometric Designs

    Get PDF
    In this and an earlier paper [17] we study combinatorial designs whose incidence matrix has two distinct singular values.These generalize (v, k, ë) designs, and include uniform multiplicative designs and partial geometric designs.Here we study the latter, which are precisely the designs with constant replication and block size.We collect most known results, give new characterization results, and we enumerate, partly by computer, all small ones.matrices;singularities;geometry;combinatorics

    Some Spectral and Quasi-Spectral Characterizations of Distance-Regular Graphs

    Full text link
    In this paper we consider the concept of preintersection numbers of a graph. These numbers are determined by the spectrum of the adjacency matrix of the graph, and generalize the intersection numbers of a distance-regular graph. By using the preintersection numbers we give some new spectral and quasi-spectral characterizations of distance-regularity, in particular for graphs with large girth or large odd-girth

    ArcMap Hydrology Toolset: WPES, How Do I...? Quick Guide

    Get PDF
    This document provides guidance for performing hydrologic tasks using the Hydrology Toolset in ArcMap 10.x (ArcGIS Desktop). Covered here are an overview of the uses and limitations of the tools within the Hydrology Toolset, related tools from from additional ArcGIS toolsets, and step-by-step instructions for hydrologic workflows including digital elevation model (DEM) preparation, pit fill detection, burning in culverts for proper flow path routing, watershed and stream network delineation, and flow network statistics

    Survey Control with GNSS Receiver: WPES, How Do I...? Quick Guide

    Get PDF
    This document is a quick guide to establishing survey control points using a Global Navigation Satellite Systems (GNSS) receiver and processing collected point coordinate data. The WPES Research Group uses a Trimble NetR9 GNSS reference receiver, which is reflected in the specific sequences of button presses outlined in the data profile setup, field operation, and data download sections. Readers using a different receiver may still find the general workflow overview useful and should be able to use the data post-processing section directly

    ArcMap Basics: WPES, How Do I...? Quick Guide

    Get PDF
    This document is a quick guide to performing common geospatial tasks in ArcMap 10.x (ArcGIS Desktop) for new users. Covered are basic navigation of the ArcMap window; importing, opening, querying, editing, and exporting data; and map preparation. In many cases, there are multiple ways to accomplish different tasks; presented here are the methods the author finds easiest or most straightforward. Mouse click sequences and menu/tool layout may differ if using previous versions of ArcMap

    Scaling Up the Relevance of Land-Sea Connections in Coastal Bacteria Pollution Vulnerability

    Get PDF
    Bacteria pollution closures of Maine’s coastal shellfish harvest areas have substantial negative consequences for coastal businesses and communities. Sustainability solutions for Maine’s shellfish harvesting areas and businesses require new types of knowledge and information to protect water quality and public health while avoiding unnecessary fishery closures. Coastal management agencies have interests in tools to support science-based management decision-making related to pollution and sustainability solutions for businesses and communities. Prior research into land-sea connections has demonstrated uses of geographic information and statistical methods to facilitate management and science communication. Research in Maine has focused on identification and comparison of attributes influencing coastal conditions. Examinations of coastal settings based on proxy spatial data metrics for pollution sources, delivery, and residence time (SDR) attributes have demonstrated capacity to identify locations with varied pollution vulnerability when paired with water quality sampling data. This research starts from the proof of concept from previous work and cogeneration of knowledge with stakeholders in Maine. Advancements include the strategic process for selecting and assembling proxy spatial data metrics, procedures to identify coastal pollution response units (CPRUs), and approaches used to document associations of CPRU settings with pollution problems. Outcomes include delineations of land-sea connection domains and identification of seven CPRU setting types. Results indicate similarity among locations derived from proxy metrics and bacteria sampling data based on selected pollution attributes and equal weighting of SDR attribute categories. Lands adjacent to tidal boundaries, “margin watershed areas” (MWAs), comprise 9.8% of the CPRU land area. However, MWAs were not found to increase the predictability of vulnerability to bacteria pollution. Multiple information gaps are assumed to influence results and limit direct applications from the analyses, including: 1) Biases in bacteria sampling from management activities, 2) Static nature of proxy metrics describing land-sea connection processes, 3) Domain outlet specifications, 4) Influence of large river flows and ocean input, 5) Stochastic events, 6) Equal weighting of SDR pollution culprit categories. However, research outcomes provide a defensible framework for coastal pollution vulnerability evaluations, guidance for targeting pollution problems, and new information to support research and management decisions related to coastal planning and monitoring activities
    corecore