Why Metrology Matters
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Calculating Growing Degree Days by Jim Nugent District Horticulturist Michigan State University
Calculating Growing Degree Days By Jim Nugent District Horticulturist Michigan State University Are you calculating degree day accumulations and finding your values don't match the values being reported by MSU or your neighbor's electronic data collection unit? There is a logical reason! Three different methods are used to calculate degree days; i.e., 1) Averaging Method; 2) Baskerville-Emin (BE) Method; and 3) Electronic Real-time Data Collection. All methods attempt to calculate the heat accumulation above a minimum threshold temperature, often referred to the base temperature. Once both the daily maximum and minimum temperatures get above the minimum threshold temperature, (i.e., base temperature of 42degrees, 50degrees or whatever other base temperature of interest) then all methods are fairly comparable. However, differences do occur and these are accentuated in an exceptionally long period of cool spring temperatures, such as we experienced this year. Let me briefly explain: 1. Averaging Method: Easy to calculate Degree Days(DD) = Average daily temp. - Base Temp. = (max. + min.) / 2 - Base temp. If answer is negative, assume 0. Example: Calculate DD Base 50 given 65 degrees max. and 40 degrees min. Avg. = (65 + 40) / 2 = 52.5 degrees DD base 50 = 52.5 - 50 = 2.5 degrees. But look what happens given a maximum of 60 degrees and a minimum of 35 degrees: Avg. = (60 + 35) / 2 = 47.5 DD base 50 = 47.5 - 50 = -2.5 = 0 degrees. The maximum temperature was higher than the base of 50° , but no degree days were accumulated. A grower called about the first of June reporting only about 40% of the DD50 that we have recorded. -
A Concurrent PASCAL Compiler for Minicomputers
512 Appendix A DIFFERENCES BETWEEN UCSD'S PASCAL AND STANDARD PASCAL The PASCAL language used in this book contains most of the features described by K. Jensen and N. Wirth in PASCAL User Manual and Report, Springer Verlag, 1975. We refer to the PASCAL defined by Jensen and Wirth as "Standard" PASCAL, because of its widespread acceptance even though no international standard for the language has yet been established. The PASCAL used in this book has been implemented at University of California San Diego (UCSD) in a complete software system for use on a variety of small stand-alone microcomputers. This will be referred to as "UCSD PASCAL", which differs from the standard by a small number of omissions, a very small number of alterations, and several extensions. This appendix provides a very brief summary Of these differences. Only the PASCAL constructs used within this book will be mentioned herein. Documents are available from the author's group at UCSD describing UCSD PASCAL in detail. 1. CASE Statements Jensen & Wirth state that if there is no label equal to the value of the case statement selector, then the result of the case statement is undefined. UCSD PASCAL treats this situation by leaving the case statement normally with no action being taken. 2. Comments In UCSD PASCAL, a comment appears between the delimiting symbols "(*" and "*)". If the opening delimiter is followed immediately by a dollar sign, as in "(*$", then the remainder of the comment is treated as a directive to the compiler. The only compiler directive mentioned in this book is (*$G+*), which tells the compiler to allow the use of GOTO statements. -
2 Amount and Concentration: Making and Diluting Solutions 2 Amount and Concentration; Making and Diluting Solutions
Essential Maths for Medics and Vets Reference Materials Module 2. Amount and Concentration. 2 Amount and concentration: making and diluting solutions 2 Amount and concentration; making and diluting solutions.........................................................1 2A Rationale.............................................................................................................................1 2B Distinguishing between amount and concentration, g and %w/v..........................................1 2C Distinguishing between amount and concentration, moles and molar...................................2 2D Practice converting g/L to M and vice versa........................................................................3 2E Diluting Solutions ...............................................................................................................5 2F Practice calculating dilutions ...............................................................................................6 Summary of learning objectives................................................................................................7 2A Rationale Biological and biochemical investigations rely completely upon being able to detect the concentration of a variety of substances. For example, in diabetics it is important to know the concentration of glucose in the blood and you may also need to be able to calculate how much insulin would need to be dissolved in a certain volume of saline so as to give the right amount in a 1ml injection volume. It is also vitally -
A Learner's Guide to SI Units and Their Conversion
A Learner's Guide to SI Units and their Conversion October 2004 Workbook for students Learner's Guide to SI Units and their Conversion their and Units SI to Guide Learner's Edexcel A London Qualifications is one of the leading examining and awarding bodies in the UK and throughout the world. It incorporates all the qualifications previously awarded under the Edexcel and BTEC brand. We provide a wide range of qualifications including general (academic), vocational, occupational and specific programmes for employers. Through a network of UK and overseas offices, our centres receive the support they need to help them deliver their education and training programmes to learners. For further information please call Customer Services on 0870 240 9800, or visit our website at www.edexcel.org.uk Authorised by Jim Dobson Prepared by Sarah Harrison All the material in this publication is copyright © London Qualifications Limited 2004 CONTENTS Introduction 1 What are units? 2 Operations with units 5 Submultiple and multiple units 9 Conversion of units 11 Conversion examples and exercises 13 Length 13 Area 14 Volume 15 Mass 16 Time 17 Temperature 18 Density 19 Force 20 Stress and pressure 21 Answers to exercises 23 Introduction One of the important areas where Science and Technology students need support is in the conversion of units. This booklet is designed to be useful for students in all Science, Technology and Engineering subjects. This booklet has been produced to: S introduce students to SI base and derived units and S help students with the conversion of multiple and sub-multiple units to SI base and derived units. -
Units and Conversions
Units and Conversions This unit of the Metrology Fundamentals series was developed by the Mitutoyo Institute of Metrology, the educational department within Mitutoyo America Corporation. The Mitutoyo Institute of Metrology provides educational courses and free on-demand resources across a wide variety of measurement related topics including basic inspection techniques, principles of dimensional metrology, calibration methods, and GD&T. For more information on the educational opportunities available from Mitutoyo America Corporation, visit us at www.mitutoyo.com/education. This technical bulletin addresses an important aspect of the language of measurement – the units used when reporting or discussing measured values. The dimensioning and tolerancing practices used on engineering drawings and related product specifications use either decimal inch (in) or millimeter (mm) units. Dimensional measurements are therefore usually reported in either of these units, but there are a number of variations and conversions that must be understood. Measurement accuracy, equipment specifications, measured deviations, and errors are typically very small numbers, and therefore a more practical spoken language of units has grown out of manufacturing and precision measurement practice. Metric System In the metric system (SI or International System of Units), the fundamental unit of length is the meter (m). Engineering drawings and measurement systems use the millimeter (mm), which is one thousandths of a meter (1 mm = 0.001 m). In general practice, however, the common spoken unit is the “micron”, which is slang for the micrometer (m), one millionth of a meter (1 m = 0.001 mm = 0.000001 m). In more rare cases, the nanometer (nm) is used, which is one billionth of a meter. -
An Atomic Physics Perspective on the New Kilogram Defined by Planck's Constant
An atomic physics perspective on the new kilogram defined by Planck’s constant (Wolfgang Ketterle and Alan O. Jamison, MIT) (Manuscript submitted to Physics Today) On May 20, the kilogram will no longer be defined by the artefact in Paris, but through the definition1 of Planck’s constant h=6.626 070 15*10-34 kg m2/s. This is the result of advances in metrology: The best two measurements of h, the Watt balance and the silicon spheres, have now reached an accuracy similar to the mass drift of the ur-kilogram in Paris over 130 years. At this point, the General Conference on Weights and Measures decided to use the precisely measured numerical value of h as the definition of h, which then defines the unit of the kilogram. But how can we now explain in simple terms what exactly one kilogram is? How do fixed numerical values of h, the speed of light c and the Cs hyperfine frequency νCs define the kilogram? In this article we give a simple conceptual picture of the new kilogram and relate it to the practical realizations of the kilogram. A similar change occurred in 1983 for the definition of the meter when the speed of light was defined to be 299 792 458 m/s. Since the second was the time required for 9 192 631 770 oscillations of hyperfine radiation from a cesium atom, defining the speed of light defined the meter as the distance travelled by light in 1/9192631770 of a second, or equivalently, as 9192631770/299792458 times the wavelength of the cesium hyperfine radiation. -
GNBS International System of Units Booklet
I Table of INTRODUCTION CONTENTS The purpose of this booklet Learn About... 3 is to enable Guyanese to become familiar with • Guyana National Bureau 3 the metric system and, in of Standards (GNBS). particular, the International System of Units or SI Units. With most of the world We Look to the Future using the metric system of 5 measurements, these SI • Why do we need 5 units are now an intrinsic Measurement Standards? part of our lives. • The Role of Measurements 6 The meat, flour, fruit and in our Daily Lives. vegetables we buy; the pills, tablets and capsules doctors prescribe; the distances vehicles cover and boats Learn More On... 7 sail and athletes run, as • What is the SI? 7 well as fabric bought for our garments to be made • Why use the SI? 8 from are all weighed and measured using SI units. Given this trend, Guyana Learn the Units 9 must fully embrace metric • What are the SI Units? 9 measurements. Thus, this booklet intends to promote • The Basics of the Metric 11 a culture in which Guyanese System in use everyday. not only “think metric” but also actively use the SI units - The Kilogram 11 in their everyday lives. II III - The Kilometre 13 Guyana National - The Litre 15 Bureau of learn Standards Using the Basic Units 17 about... • Converting between Units 17 (GNBS) • Temperature 18 The Guyana National Bureau of Standards (GNBS) operates under • Writing Dates 19 the Ministry of Tourism, Industry and commerce as a semi - • Writing Times 19 -autonomous governmental organization responsible for standards and quality in Guyana. -
Operating Instructions Ac Snap-Around Volt-Ohm
4.5) HOW TO USE POINTER LOCK & RANGE FINDER LIFETIME LIMITED WARRANTY 05/06 From #174-1 SYMBOLS The attention to detail of this fine snap-around instrument is further enhanced by OPERATING INSTRUCTIONS (1) Slide the pointer lock button to the left. This allows easy readings in dimly lit the application of Sperry's unmatched service and concern for detail and or crowded cable areas (Fig.8). reliability. AC SNAP-AROUND VOLT-OHM-AMMETER (2) For quick and easy identification the dial drum is marked with the symbols as These Sperry snap-arounds are internationally accepted by craftsman and illustrated below (Fig.9). servicemen for their unmatched performance. All Sperry's snap-around MODEL SPR-300 PLUS & SPR-300 PLUS A instruments are unconditionally warranted against defects in material and Pointer Ampere Higher workmanship under normal conditions of use and service; our obligations under Lock range range to the to the this warranty being limited to repairing or replacing, free of charge, at Sperry's right. right. sole option, any such Sperry snap-around instrument that malfunctions under normal operating conditions at rated use. 1 Lower Lower range range to the to the left. left. REPLACEMENT PROCEDURE Fig.8 Fig.9 Securely wrap the instrument and its accessories in a box or mailing bag and ship prepaid to the address below. Be sure to include your name and address, as 5) BATTERY & FUSE REPLACEMENT well as the name of the distributor, with a copy of your invoice from whom the (1) Remove the screw on the back of the case for battery and fuse replacement unit was purchased, clearly identifying the model number and date of purchase. -
Consultative Committee for Amount of Substance; Metrology in Chemistry and Biology CCQM Working Group on Isotope Ratios (IRWG) S
Consultative Committee for Amount of Substance; Metrology in Chemistry and Biology CCQM Working Group on Isotope Ratios (IRWG) Strategy for Rolling Programme Development (2021-2030) 1. EXECUTIVE SUMMARY In April 2017, the Consultative Committee for Amount of Substance; Metrology in Chemistry and Biology (CCQM) established a task group to study the metrological state of isotope ratio measurements and to formulate recommendations to the Consultative Committee (CC) regarding potential engagement in this field. In April 2018 the Isotope Ratio Working Group (IRWG) was established by the CCQM based on the recommendation of the task group. The main focus of the IRWG is on the stable isotope ratio measurement science activities needed to improve measurement comparability to advance the science of isotope ratio measurement among National Metrology Institutes (NMIs) and Designated Institutes (DIs) focused on serving stake holder isotope ratio measurement needs. During the current five-year mandate, it is expected that the IRWG will make significant advances in: i. delta scale definition, ii. measurement comparability of relative isotope ratio measurements, iii. comparable measurement capabilities for C and N isotope ratio measurement; and iv. the understanding of calibration modalities used in metal isotope ratio characterization. 2. SCIENTIFIC, ECONOMIC AND SOCIAL CHALLENGES Isotopes have long been recognized as markers for a wide variety of molecular processes. Indeed, applications where isotope ratios are used provide scientific, economic, and social value. Early applications of isotope measurements were recognized with the 1943 Nobel Prize for Chemistry which included the determination of the water content in the human body, determination of solubility of various low-solubility salts, and development of the isotope dilution method which has since become the cornerstone of analytical chemistry. -
Lord Kelvin and the Age of the Earth.Pdf
ME201/MTH281/ME400/CHE400 Lord Kelvin and the Age of the Earth Lord Kelvin (1824 - 1907) 1. About Lord Kelvin Lord Kelvin was born William Thomson in Belfast Ireland in 1824. He attended Glasgow University from the age of 10, and later took his BA at Cambridge. He was appointed Professor of Natural Philosophy at Glasgow in 1846, a position he retained the rest of his life. He worked on a broad range of topics in physics, including thermody- namics, electricity and magnetism, hydrodynamics, atomic physics, and earth science. He also had a strong interest in practical problems, and in 1866 he was knighted for his work on the transtlantic cable. In 1892 he became Baron Kelvin, and this name survives as the name of the absolute temperature scale which he proposed in 1848. During his long career, Kelvin published more than 600 papers. He was elected to the Royal Society in 1851, and served as president of that organization from 1890 to 1895. The information in this section and the picture above were taken from a very useful web site called the MacTu- tor History of Mathematics Archive, sponsored by St. Andrews University. The web address is http://www-history.mcs.st-and.ac.uk/~history/ 2 kelvin.nb 2. The Age of the Earth The earth shows it age in many ways. Some techniques for estimating this age require us to observe the present state of a time-dependent process, and from that observation infer the time at which the process started. If we believe that the process started when the earth was formed, we get an estimate of the earth's age. -
Units and Magnitudes (Lecture Notes)
physics 8.701 topic 2 Frank Wilczek Units and Magnitudes (lecture notes) This lecture has two parts. The first part is mainly a practical guide to the measurement units that dominate the particle physics literature, and culture. The second part is a quasi-philosophical discussion of deep issues around unit systems, including a comparison of atomic, particle ("strong") and Planck units. For a more extended, profound treatment of the second part issues, see arxiv.org/pdf/0708.4361v1.pdf . Because special relativity and quantum mechanics permeate modern particle physics, it is useful to employ units so that c = ħ = 1. In other words, we report velocities as multiples the speed of light c, and actions (or equivalently angular momenta) as multiples of the rationalized Planck's constant ħ, which is the original Planck constant h divided by 2π. 27 August 2013 physics 8.701 topic 2 Frank Wilczek In classical physics one usually keeps separate units for mass, length and time. I invite you to think about why! (I'll give you my take on it later.) To bring out the "dimensional" features of particle physics units without excess baggage, it is helpful to keep track of powers of mass M, length L, and time T without regard to magnitudes, in the form When these are both set equal to 1, the M, L, T system collapses to just one independent dimension. So we can - and usually do - consider everything as having the units of some power of mass. Thus for energy we have while for momentum 27 August 2013 physics 8.701 topic 2 Frank Wilczek and for length so that energy and momentum have the units of mass, while length has the units of inverse mass. -
Misura E Strumenti Di Misura
® MISURA E STRUMENTI DI MISURA (G) MISURA: g = G : grandezza (numero) U(G) U(G) : unita' di misura di G Come si effettua la misura ? diretta MISURA indiretta confronto diretto con unita' di misura DIRETTA: (Grandezze omogenee) con strumento "tarato" es. : termometro, voltmetro ... INDIRETTA: dalla relazione fisica con altre grandezze es. : P = F/S STRUMENTO DI MISURA: dispositivo per determinare g 30 RIVELATORE: sensibile a grandezza da misurare (sollecitazione) TRASDUTTORE: trasforma sollecitazione STRUMENTO in grandezza facilmente misurabile VISUALIZZATORE: visualizza grandezza trasformata RIVELATORE: Mercurio Es. TERMOMETRO TRASDUTTORE: Mercurio + capillare VISUALIZZATORE: capillare + scala tarata RIVELATORE: bobina mobile in campo magnetico Es. AMPEROMETRO TRASDUTTORE: movimento bobina (rotazione ago) VISUALIZZATORE: posizione ago su scala "tarata" 31 CARATTERISTICHE STRUMENTO INTERVALLO FUNZ. (valore min-max grandezza) PRONTEZZA: tempo necessario per reagire alla sollecitazione τ τ = tempo caratteristico strumento τ (termometro) ~ secondi τ (oscilloscopio) ~ 10 -9 s SENSIBILITA`: ∆R(G) dR R(G): risposta S = = ∆V(G) dV V(G): valore grandezza se R lineare in V(G): S = cost. Altrimenti S funzione di V(G) (Ohmetro) Dimensioni : [G] -1 Es. Bilancia: S in DIV/mg 32 PRECISIONE: capacita' strumento a dare stessa risposta a stessa sollecitazione MISURE RIPETUTE (sensibilit : 1/∆g) N N g(G) g(G) ∆g GIUSTEZZA: assenza di effetti sistematici Difetto strumento (termometro: capillare a sezione variabile) Uso strumento in condizioni errate (regolo