Search results for: a-distance-of-ground

Time Distance and Drawdown Relationships in a Pumped Ground water Basin

Author : Fred Kunkel
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Antennas And Wave Propagation

Author : K.A.Bakshi A.V.Bakshi U.A.Bakshi
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Antenna Fundamentals Introduction, Radiation mechanism - Single wire, 2 wire, Dipoles, Current distribution on a thin wire antenna. Antenna parameters - Radiation patterns, Patterns in principal planes, Main lobe and side lobes, Beamwidths, Beam area, Radiation intensity, Beam efficiency, Directivity, Gain and resolution, Antenna apertures, Aperture efficiency, Effective height related problems.Thin Linear Wire AntennasRetarded potentials, Radiation from small electric dipole, Quarterwave monopole and halfwave dipole - Current distributions, Evaluation of field components, Power radiated, Radiation resistance, Beamwidths, Directivity, Effective area and effective height. Natural current distributions, Fields and patterns of thin linear center-fed antennas of different lengths, Radiation resistance at a point which is not current maximum. Antenna theorems - Applicability and proofs for equivalence of directional characteristics, Loop antennas : Small loops - Field components, Comparison of far fields of small loop and short dipole, Concept of short magnetic dipole, D and R relations for small loops.Antenna Arrays2 element arrays - Different cases, Principle of pattern multiplication, N element uniform linear arrays - Broadside, Endfire arrays, EFA with increased directivity, Derivation of their characteristics and comparison; Concept of scanning arrays, Directivity relations (no derivations), Related problems, Binomial arrays, Effects of uniform and non-uniform amplitude distributions, Design relations.Non-Resonant RadiatorsIntroduction, Travelling wave radiators - Basic concepts, Longwire antennas - Field strength calculations and patterns, V-antennas, Rhombic antennas and design relations, Broadband antennas : Helical antennas - Significance, Geometry, Basic properties; Design considerations for monofilar helical antennas in axial mode and normal modes (Qualitative treatment).VHF, UHF and Microwave Antennas - IArrays with parasitic elements, Yagi-Uda arrays, Folded dipoles and their characteristics.Reflector antennas Flat sheet and corner reflectors, Paraboloidal reflectors - Geometry, Characteristics, Types of feeds, F/D ratio, Spill over, Back lobes, Aperture blocking, Off-set feeds, Cassegrainian feeds.VHF, UHF and Microwave Antennas - IIHorn antennas - Types, Optimum horns, Design characteristics of pyramidal horns; Lens antennas - Geometry, Features, Dielectric lenses and zoning, Applications.Antenna measurements - Patterns required, setup, Distance criterion, Directivity and gain measurements (Comparison, Absolute and 3-Antenna methods).Wave Propagation - IConcepts of propagation, Frequency ranges and types of propagations. Ground wave propagation - Characteristics, Parameters, Wave tilt, Flat and spherical earth considerations. Sky wave propagation - Formation of ionospheric layers and their characteristics, Mechanism of reflection and refraction, Critical frequency, MUF and skip distance - Calculations for flat and spherical earth cases, Optimum frequency, LUHF, Virtual height, Ionospheric abnormalities, Ionospheric absorption.Wave Propagation - IIFundamental equation for free-space propagation, Basic transmission loss calculations. Space wave propagation - Mechanism, LOS and radio horizon. Tropospheric wave propagation - Radius of curvature of path, Effective earth's radius, Effect of earth's curvature, Field strength calculations, M-curves and Duct propagation, Tropospheric scattering.

Echoes from a Distance

Author : King Joe
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Shortly after I had returned from a foreign trip some years ago, an old friend saw me and quickly noticed that I had gone partially bald. He was startled. So, he spontaneously yelled a seemingly tough question at me: What happened to the hairs on your head? Spontaneously too, I yelled an answer back at him: Nature took them in place of the wisdom that I couldnt pay for! And we teased and laughed. My friend thought I had joked, but I knew I hadnt. However, Ill leave the judgment to you. By the time youre done digesting the substance of this more than compelling masterpiece, Id like to know your stand. Had I joked or had I not?

Aerial Photography and Image Interpretation

Author : David P. Paine
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Includes new material on orthophotography, soft photogrammetry, and digital image capture and interpretation. * Introduces the latest non-photographic and space-based imaging platforms and sensors (Landsat, LIDAR, thermal, multispectral). * Provides new information on elementary sampling techniques and statistics.

Relationships and Patterns of Conflict Resolution

Author : Peter D. Ladd
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Slide open the pages to reveal what's really happening in Pontypandy and help Fireman Sam complete his rescues. Will he save the day?

Applied Ground water Hydrology and Well Hydraulics

Author : Michael Kasenow
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Technique for Improving the Accuracy of Air to ground Radio Distance Measurement Systems

Author : Lockett Eason Wood
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A 7 Corsair Pilot s Flight Operating Manual

Author : United States Navy
File Size : 44.32 MB
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ought¿s A-7 Corsair II served the U.S. Navy for over over two decades, and flew with distinction during the Vietnam conflict. The subsonic A-7 was based on Chance Vought¿s supersonic F-8 Crusader. It boasted a heads-up display, an inertial navigation system, and other innovations. The plane entered service in 1966, and served in Vietnam in late 1967. Its performance was impressive. The USS Ranger¿s VA-147 flew over 1,400 sorties with the loss of only one aircraft. The Air Force purchased an advanced version, the A-7D, equipped with a more powerful engine. The plane later flew missions over Lebanon, Libya, Grenada, Panama, and Iraq. The last planes in U.S inventory were retired in 1991. Originally printed by the U.S. Navy and Vought, this handbook for the A-7 provides a fascinating glimpse inside the cockpit of this famous aircraft. Originally classified ¿restricted¿, the manual was recently declassified and is here reprinted in book form.

A Complete Course In Certificate Geography Vol Ii

Author : V. N. Nigam
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This Book Has Been Designed Keeping The Idea In Mind That Geography Is Not Merely A Description Of The Earth But A Thorough Study Of The Interaction Of Man With His Physicl Environments. Vo. I Contains Principles Of Geography And World Studies And Vol. Ii Geography Of South Asia With Special Reference To India. Great Stress Has Been Laid An Sketch Maps And Diagrams, Which Are Of Great Practical Utility In The Interpretation Of The Subject Matter.

Electromagnetic Compatibility Engineering

Author : Henry W. Ott
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Praise for Noise Reduction Techniques IN electronic systems "Henry Ott has literally 'written the book' on the subject of EMC. . . . He not only knows the subject, but has the rare ability to communicate that knowledge to others." —EE Times Electromagnetic Compatibility Engineering is a completely revised, expanded, and updated version of Henry Ott's popular book Noise Reduction Techniques in Electronic Systems. It reflects the most recent developments in the field of electromagnetic compatibility (EMC) and noise reduction¿and their practical applications to the design of analog and digital circuits in computer, home entertainment, medical, telecom, industrial process control, and automotive equipment, as well as military and aerospace systems. While maintaining and updating the core information—such as cabling, grounding, filtering, shielding, digital circuit grounding and layout, and ESD—that made the previous book such a wide success, this new book includes additional coverage of: Equipment/systems grounding Switching power supplies and variable-speed motor drives Digital circuit power distribution and decoupling PCB layout and stack-up Mixed-signal PCB layout RF and transient immunity Power line disturbances Precompliance EMC measurements New appendices on dipole antennae, the theory of partial inductance, and the ten most common EMC problems The concepts presented are applicable to analog and digital circuits operating from below audio frequencies to those in the GHz range. Throughout the book, an emphasis is placed on cost-effective EMC designs, with the amount and complexity of mathematics kept to the strictest minimum. Complemented with over 250 problems with answers, Electromagnetic Compatibility Engineering equips readers with the knowledge needed to design electronic equipment that is compatible with the electromagnetic environment and compliant with national and international EMC regulations. It is an essential resource for practicing engineers who face EMC and regulatory compliance issues and an ideal textbook for EE courses at the advanced undergraduate and graduate levels.

Close Up at a Distance

Author : Laura Kurgan
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Maps poised at the intersection of art, architecture, activism, and geography trace a profound shift in our understanding and experience of space. The maps in this book are drawn with satellites, assembled with pixels radioed from outer space, and constructed from statistics; they record situations of intense conflict and express fundamental transformations in our ways of seeing and of experiencing space. These maps are built with Global Positioning Systems (GPS), remote sensing satellites, or Geographic Information Systems (GIS): digital spatial hardware and software designed for such military and governmental uses as reconnaissance, secrecy, monitoring, ballistics, the census, and national security. Rather than shying away from the politics and complexities of their intended uses, in Close Up at a Distance Laura Kurgan attempts to illuminate them. Poised at the intersection of art, architecture, activism, and geography, her analysis uncovers the implicit biases of the new views, the means of recording information they present, and the new spaces they have opened up. Her presentation of these maps reclaims, repurposes, and discovers new and even inadvertent uses for them, including documentary, memorial, preservation, interpretation, political, or simply aesthetic. GPS has been available to both civilians and the military since 1991; the World Wide Web democratized the distribution of data in 1992; Google Earth has captured global bird's-eye views since 2005. Technology has brought about a revolutionary shift in our ability to navigate, inhabit, and define the spatial realm. The traces of interactions, both physical and virtual, charted by the maps in Close Up at a Distance define this shift.

Seismic Ground Motion In Large Urban Areas

Author : Giuliano F. Panza
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The accelerated, and often uncontrolled, growth of the cities has contributed to the ecological transformation of their immediate surroundings. Factors contributing to the urban vulnerability include: lowering or rising of the water table, subsidence, loss of bearing capacity of soil foundations and instability of slopes. Recent catastrophic earthquakes highlight the poor understanding by decision makers of seismic related risk, as well as the tendency of some builders to use the cheapest designs and construction materials to increase short-term economic returns on their investment. Losses from earthquakes will continue to increase if we do not shift towards proactive solution. Disaster reduction is both an issue for consideration in the sustainable development agenda and a cross-cutting issue relating to the social, economic, environmental and humanitarian sectors. As location is the key factor, which determines the level of risk associated with a hazard, land-use plans and mapping should be used as tools to identify the most suitable usage for vulnerable areas.

The woodlands or A treatise on the preparing of ground for planting on the planting c of forest trees and underwoods

Author : William Cobbett
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The Woodlands Or A Treatise on the Preparing of Ground for Planting on the Planting on the Cultivating on the Pruning and on the Cutting Down of Forest Trees and Underwoods Describing the Usual Growth and Size and the Uses of Each Sort of Tree the Seed of Each the Season and Manner of Collecting the Seed the Manner of Preserving and of Sowing It and Also the Manner of Managing the Young Plants Until Fit to Plant Out the Trees Being Arranged in Alphabetical Order and the List of Them Including Those of America as Well as Those of England and the English French and Latin Name Being Prefixed to the Directions Relative to Each Tree Respectively

Author : William Cobbett
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Effects of fluctuating river pool stages on ground water levels in the adjacent alluvial aquifer in the lower Arkansas River Arkansas

Author : D. A. Freiwald
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War at a Distance

Author : Mary A. Favret
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What does it mean to live during wartime away from the battle zone? What is it like for citizens to go about daily routines while their country sends soldiers to kill and be killed across the globe? Timely and thought-provoking, War at a Distance considers how those left on the home front register wars and wartime in their everyday lives, particularly when military conflict remains removed from immediate perception, available only through media forms. Looking back over two centuries, Mary Favret locates the origins of modern wartime in the Napoleonic era and describes how global military operations affected the British populace, as the nation's army and navy waged battles far from home for decades. She reveals that the literature and art produced in Britain during the late eighteenth and early nineteenth centuries obsessively cultivated means for feeling as much as understanding such wars, and established forms still relevant today. Favret examines wartime literature and art as varied as meditations on the Iliad, the history of meteorology, landscape painting in India, and popular poetry in newspapers and periodicals; she locates the embedded sense of war and dislocation in works ranging from Austen, Coleridge, and Wordsworth to Woolf, Stevens, and Sebald; and she contemplates how literature provides the public with methods for responding to violent calamities happening elsewhere. Bringing to light Romanticism's legacy in reflections on modern warfare, this book shows that war's absent presence affects home in deep and irrevocable ways.

Map Reading

Author : Alexander S. Job
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Operator s Manual for Army Models C 12A C 12C and C 12D Aircraft

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The Climate Near the Ground

Author : Rudolf Geiger
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This revised and updated edition of Rudolf Geiger's classic text provides a clear and vivid description of the surface microclimate, its physical basis, and its interactions with the biosphere. The book explains the principles of microclimatology and illustrates how they apply to a wide array of subfields. Those new to the field will find it especially valuable as a guide to understanding and quantifying the vast and ever-increasing literature on the subject. Designed as an introductory text for students in environmental science, this book will also be an essential reference for scientists seeking a clear understanding of the nature and physical basis of the climate near the ground, and its interactions with the biosphere.

Ground Freezing Effects on Soil Erosion of Army Training Lands Part 1 Initial Test Results

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Military maneuvers damage vegetation and compact and rut soils on training lands, thereby increasing the likelihood of hillslope runoff and soil erosion. Soil Freeze-Thaw (FT) processes can change the hydraulic geometry and roughness of vehicular ruts and reduce soil compaction, which often partially restores the water infiltration rate that existed before compaction. The efficiency of these FT-induced 'repairs' depends on soil water content and FT intensity. Initial tests showed that: (1) an experimental soil bin designed and constructed for rut experiments allows acceptable simulation of field soil FT, and (2) the hydraulic geometry of a rectangular rill in a fine silt soil with an initial volumetric water content of 36% changes dramatically due to rill sideslope slumping during thaw. Future experiments will compare differences in the response of natural rills and vehicular ruts to FT-induced soil failure, and investigate the effects of FT on soil erodibility and the influences of snow cover on soil erosion processes in the spring.