Visual Acuity Measurements with Three Commercial Screening Devices
Author: John H. Sulzman
Publisher:
Published: 1946
Total Pages: 250
ISBN-13:
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Forward Scatter Meter Measurements of Slant Visual Range
Author: Wayne S. Hering
Publisher:
Published: 1978
Total Pages: 32
ISBN-13:
DOWNLOAD EBOOKThe potential for remote tower measurements of point visibility in the determination of slant range visibility for aircraft landing operations was explored through analysis of data collected at the Air Force Geophysics Laboratory Weather Test Facility at Otis AFB, Massachusetts. This report described initial experiments that deal with an analysis of the small scale variability of extinction coefficient in time and space. Data from two instrumented towers spaced 1500 ft apart were classified for investigation of the horizontal variability of visibility at elevations up to 100 ft and space-time variability for lag periods from 0 to 10 minutes. The preliminary tests give additional evidence that the runway visual range (RVR) measurements alone often are not representative of pilot visibility during approach and touchdown. Remote measurements of visibility using either a 50-ft or 100-ft instrumented tower would add significantly to the real safety of 'see-to-land' operations under conditions of Categories I, II, and IIIa through an improved description of conditions related to airfield visibility. (Author).
The Psychophysical Measurement of Visual Function
Author: Thomas T. Norton
Publisher:
Published: 2002
Total Pages: 0
ISBN-13: 9780750699358
DOWNLOAD EBOOKThis easy-to-follow book presents the fundamentals of how to measure vision and visual function. It offers a solid understanding of the neural basis of vision where it is known or can be deduced. Each chapter features an overview summarizing the chapter, declarative headings throughout for instant review, study guide questions, and a glossary. Explanations of the neural mechanisms underlying visual function help readers understand how vision is measured. It details the scientific basis of how visual function is measured and applies laboratory measurement to clinical procedures.
Charge Determination by Thin-down Track Width Measurements
Author: Y. K. Lim
Publisher:
Published: 1966
Total Pages: 16
ISBN-13:
DOWNLOAD EBOOKMean track width data for tracks of multiply-charged ions in nuclear emulsions in the thin-down region from published works and our own measurements have been analyzed and found to be reducible to a relation obtainable from a simple model proposed by Bizzeti and Della Corte. The use of this relation in calibration and charge determination is discussed.
Visual Impairments
Author: National Research Council
Publisher: National Academies Press
Published: 2002-08-17
Total Pages: 369
ISBN-13: 0309083486
DOWNLOAD EBOOKWhen children and adults apply for disability benefits and claim that a visual impairment has limited their ability to function, the U.S. Social Security Administration (SSA) is required to determine their eligibility. To ensure that these determinations are made fairly and consistently, SSA has developed criteria for eligibility and a process for assessing each claimant against the criteria. Visual Impairments: Determining Eligibility for Social Security Benefits examines SSA's methods of determining disability for people with visual impairments, recommends changes that could be made now to improve the process and the outcomes, and identifies research needed to develop improved methods for the future. The report assesses tests of visual function, including visual acuity and visual fields whether visual impairments could be measured directly through visual task performance or other means of assessing disability. These other means include job analysis databases, which include information on the importance of vision to job tasks or skills, and measures of health-related quality of life, which take a person-centered approach to assessing visual function testing of infants and children, which differs in important ways from standard adult tests.
Springer Handbook of Atmospheric Measurements
Author: Thomas Foken
Publisher: Springer Nature
Published: 2021-11-09
Total Pages: 1761
ISBN-13: 3030521710
DOWNLOAD EBOOKThis practical handbook provides a clearly structured, concise and comprehensive account of the huge variety of atmospheric and related measurements relevant to meteorologists and for the purpose of weather forecasting and climate research, but also to the practitioner in the wider field of environmental physics and ecology. The Springer Handbook of Atmospheric Measurements is divided into six parts: The first part offers instructive descriptions of the basics of atmospheric measurements and the multitude of their influencing factors, fundamentals of quality control and standardization, as well as equations and tables of atmospheric, water, and soil quantities. The subsequent parts present classical in-situ measurements as well as remote sensing techniques from both ground-based as well as airborn or satellite-based methods. The next part focusses on complex measurements and methods that integrate different techniques to establish more holistic data. Brief discussions of measurements in soils and water, at plants, in urban and rural environments and for renewable energies demonstrate the potential of such applications. The final part provides an overview of atmospheric and ecological networks. Written by distinguished experts from academia and industry, each of the 64 chapters provides in-depth discussions of the available devices with their specifications, aspects of quality control, maintenance as well as their potential for the future. A large number of thoroughly compiled tables of physical quantities, sensors and system characteristics make this handbook a unique, universal and useful reference for the practitioner and absolutely essential for researchers, students, and technicians.
Measurements using Optic and RF Waves
Author: Frédérique de Fornel
Publisher: John Wiley & Sons
Published: 2013-02-04
Total Pages: 238
ISBN-13: 1118586344
DOWNLOAD EBOOKThe scientific and technical basis underpinning modern measurement techniques used for electromagnetic quantities and phenonema is necessarily wide-ranging, as the electromagnetic environment spans all possible frequencies and wavelengths. Measurements must be applicable in fields as varied as nanotechnologies, telecommunications, meteorology, geo-location, radio-astronomy, health, biology, and many others. In order to adequately cover the many different facets of the topic, this book provides examples from the entire range of the electromagnetic spectrum — covering frequencies from several hertz to terahertz, and considering wavelength distances ranging from nanometers to light-years in optics. It then provides coverage of the various measurement techniques using electromagnetic waves for various applications, devoting chapters to each different field of application. This comprehensive book gives detailed information on: the various techniques and methods available to measure the key characteristics of electromagnetic waves, in terms of the local field and phase for a broad field of frequencies; determination of physical quantities such as distance, time, etc., using electromagnetic properties; new approaches to measurements in the field of electromagnetic distribution in complex structures media, such as biological tissues and in the nanosciences.
Measurements of Heat Transfer, Flow, and Pressures in a Simulated Turbine Blade Internal Cooling Passage
Author: Louis M. Russell
Publisher:
Published: 1997
Total Pages: 30
ISBN-13:
DOWNLOAD EBOOKAn experimental study was made to obtain quantitative information on heat transfer, flow, and pressure distribution in a branched duct test section that had several significant features of an internal cooling passage of a turbine blade. The objective of this study was to generate a set of experimental data that could be used for validation of computer codes that would be used to model internal cooling. Surface heat transfer coefficients and entrance flow conditions were measured at nominal entrance Reynolds numbers of 45 000, 335 000, and 726 000. Heat transfer data were obtained by using a steady-state technique in which an Inconel heater sheet is attached to the surface and coated with liquid crystals. Visual and quantitative flow-field data from particle image velocimetry measurements for a plane at midchannel height for a Reynolds number of 45 000 were also obtained. The flow was seeded with polystyrene particles and illuminated by a laser light sheet. Pressure distribution measurements were made both on the surface with discrete holes and in the flow field with a total pressure probe. The flow-field measurements yielded flow-field velocities at selected locations. A relatively new method, pressure sensitive paint, was also used to measure surface pressure distribution. The pressure paint data obtained at Reynolds numbers of 335 000 and 726 000 compared well with the more standard method of measuring pressures by using discrete holes.
Handbook of Visual Optics, Volume One
Author: Pablo Artal
Publisher: CRC Press
Published: 2017-02-17
Total Pages: 1313
ISBN-13: 1315355728
DOWNLOAD EBOOKHandbook of Visual Optics offers an authoritative overview of encyclopedic knowledge in the field of physiological optics. It builds from fundamental concepts to the science and technology of instruments and practical procedures of vision correction, integrating expert knowledge from physics, medicine, biology, psychology, and engineering. The chapters comprehensively cover all aspects of modern study and practice, from optical principles and optics of the eye and retina to novel ophthalmic tools for imaging and visual testing, devices and techniques for visual correction, and the relationship between ocular optics and visual perception.
Measuring Health
Author: Ian McDowell
Publisher: Oxford University Press
Published: 2006-03-09
Total Pages: 1197
ISBN-13: 0199883149
DOWNLOAD EBOOKWorldwide economic constraints on health care systems have highlighted the importance of evidence-based medicine and evidence-based health policy. The resulting clinical trials and health services research studies require instruments to monitor the outcomes of care and the output of the health system. However, the over-abundance of competing measurement scales can make choosing a measure difficult at best. Measuring Health provides in-depth reviews of over 100 of the leading health measurement tools and serves as a guide for choosing among them.LNow in its third edition, this book provides a critical overview of the field of health measurement, with a technical introduction and discussion of the history and future directions for the field. This latest edition updates the information on each of the measures previously reviewed, and includes a complete new chapter on anxiety measurement to accompany the one on depression. It has also added new instruments to those previously reviewed in each of the chapters in the book.LChapters cover measurements of physical disability, social health, psychological well-being, anxiety, depression, mental status testing, pain, general health status and quality of life. Each chapter presents a tabular comparison of the quality of the instruments reviewed, followed by a detailed description of each method, covering its purpose and conceptual basis, its reliability and validity and, where possible, shows a copy of the actual scale. To ensure accuracy of the information, each review has been approved by the original author of each instrument or by an acknowledged expert.
