Definitions Of Quantities Research Articles

High-accuracy measurement of mass attenuation coefficients and the imaginary component of the atomic form factor of zinc from 8.51 keV to 11.59 keV, and X-ray absorption fine structure with investigation of zinc theory and nanostructure.

High-accuracy X-ray mass attenuation coefficients were measured from the first X-ray Extended Range Technique (XERT)-like experiment at the Australian Synchrotron. Experimentally measured mass attenuation coefficients deviate by ∼50% from the theoretical values near the zinc absorption edge, suggesting that improvements in theoretical tabulations of mass attenuation coefficients are required to bring them into better agreement with experiment. Using these values the imaginary component of the atomic form factor of zinc was determined for all the measured photon energies. The zinc K-edge jump ratio and jump factor are determined and results raise significant questions regarding the definitions of quantities used and best practice for background subtraction prior to X-ray absorption fine-structure (XAFS) analysis. The XAFS analysis shows excellent agreement between the measured and tabulated values and yields bond lengths and nanostructure of zinc with uncertainties of from 0.1% to0.3% or 0.003 Å to 0.008 Å. Significant variation from the reported crystal structure was observed, suggesting local dynamic motion of the standard crystal lattice. XAFS is sensitive to dynamic correlated motion and in principle is capable of observing local dynamic motion beyond the reach of conventional crystallography. These results for the zinc absorption coefficient, XAFS and structure are the most accurate structural refinements of zinc at room temperature.

Quantity in Quantum Mechanics and the Quantity of Quantum Information

The paper interprets the concept “operator in the separable complex Hilbert space” (particalry, “Hermitian operator” as “quantity” is defined in the “classical” quantum mechanics) by that of “quantum information”. As far as wave function is the characteristic function of the probability (density) distribution for all possible values of a certain quantity to be measured, the definition of quantity in quantum mechanics means any unitary change of the probability (density) distribution. It can be represented as a particular case of “unitary” qubits. The converse interpretation of any qubits as referring to a certain physical quantity implies its generalization to non-Hermitian operators, thus neither unitary, nor conserving energy. Their physical sense, speaking loosely, consists in exchanging temporal moments therefore being implemented out of the space-time “screen”. “Dark matter” and “dark energy” can be explained by the same generalization of “quantity” to non-Hermitian operators only secondarily projected on the pseudo-Riemannian space-time “screen” of general relativity according to Einstein's “Mach’s principle” and his field equation.

Fundamentals of the design and the operation of an intelligent tutoring system for the learning of the arithmetical and algebraic way of solving word problems

Designers of interactive learning environments with a focus on word problem solving usually have to compromise between the amount of resolution paths that a user is allowed to follow and the quality of the feedback provided. We have built an intelligent tutoring system (ITS) that is able to both track the user's actions and provide adequate supervision during the resolution. This is done without imposing any restriction on the resolution paths that are allowed. Instead, the system attempts to enforce metacognitive learning by requiring an appropriate definition of quantities before they are used. The program (a) supports both the arithmetical and algebraic way of solving problems; (b) allows the recurrence to one or more equations when solving a problem in an algebraic way; (c) determines the validity of the expressions when they are introduced; and (d) admits the incorporation of new problems without the need of being reprogrammed. In this paper, we explain the design foundations, which are mainly based on (a) a reflection of the steps that a student should follow to solve a problem in an algebraic way, and (b) the use of a domain specific notation to represent both the problem structure and the current state of the resolution process. In particular, hypergraphs are introduced as an adequate way to support tracking in both the arithmetical and algebraic case. Moreover, we offer an extensive experimental evaluation which highlights the potential of the ITS as a learning tool.

On Stochastic Analysis of the Quantities of Information in Economics

In this paper, the definition of information and data are presented with examples illustrating the differences between them. To articulate the value of information, the definition of quantities of information, based on information theory, generally considered to be founded by Claude Shannon, has been quoted. In addition, with corresponding mathematical derivations, specific examples are employed to manifest the factors that make information valuable. At last, we have a multifold discussion on the importance of information to economics. DOI: http://dx.doi.org/10.11591/ijece.v2i6.1795

2. Definitions of Quantities and Terms

2. Definitions of Quantities and Terms

2. Definitions of Quantities and Terms

2. Definitions of Quantities and Terms Journal of the International Commission on Radiation Units and Measurements, Volume 10, Issue 2, December 2010, Pages 9–11, https://doi.org/10.1093/jicru/ndq019 Published: 24 June 2016

3. Quality and Performance Measures in Bone Densitometry

Introduction This is part 2 of a core chapter of the forthcoming Report on Bone Densitometry commissioned by the International Commission on Radiation Units (ICRU). It is written with the aim to review definitions of quantities and units used in bone densitometry research and to describe parameters and methods that can be used to compare and standardize densitometric equipment and measurements. Part 2 of this chapter contains the section on fracture risk.

Some Mathematical Properties of Effective Resonator Model of 1D Dielectric Multilayer Structure

The aim of this paper is to fill in the gaps left in the construction of the effective resonator model of 1D multilayer dielectric structure. In the previous papers [1–4] the model has been proposed and its physical background and interpretation [1, 2, 5], as well as orthonormalization of modes [3, 4] have been described. However, there remain a few aspects of the model, which require a rigorous treatment or explanation. They are discussed in this paper, which is a mathematical supplement to the previous ones. Because of its purpose, general assumptions, notation and definitions of quantities (not recalled in this paper, except of a few cases) are the same as in [2–4]. Discussion of general properties of the model is the topic of Sect. 2. In the next three sections, conclusions are drawn for radiation (Sect. 3), substrate and guided modes (Sect. 4). The last section, Sect. 5, contains a summary of the paper.

Minimizing Error in the Determination of P50

The measurement of P 50 in whole blood, defined as the oxygen tension corresponding to 50% oxygen saturation, gives a quantitative measure of hemoglobin oxygen affinity. The determination of P 50 is useful for screening for hemoglobin variants in cases of unexplained anemia or erythrocytosis, both because it is easily performed and because many hemoglobin variants with abnormal oxygen affinity are “silent”, i.e., not detectable with conventional electrophoretic techniques (1). The determination of P 50 previously required obtaining several points on the oxyhemoglobin dissociation curve. The procedure was seldom performed because of the labor and specialized apparatus required. However, it was suggested >25 years ago that P 50 could be accurately calculated from single measurements of oxygen tension ( P o2) and the corresponding oxygen saturation ( S o2) (2). Since then, an improved mathematical model of the oxyhemoglobin dissociation curve (3) has been incorporated into a guideline for the so-called “single-point” determination of P 50 (4) that has been tested (5)(6) and subsequently approved by the IFCC. The single-point approach is based on the fact that a plot of log P o2 vs log[ S o2/(1 − S o2)], the so-called Hill plot, is linear over a fairly wide interval. Therefore, if one knows both the slope and one point on the line, any other point on the line can be determined. There have been different recommendations for the interval within which the single-point method is valid. Some studies have suggested that it can be used for oxygen saturations as low as 20% (5). The original IFCC guideline (4) specified saturations in the interval between 40% and 80%, and a subsequent IFCC document on definitions of quantities used in blood pH and gas analysis (7) extended the upper limit to 90% saturation. …

Quantities, Units and Terms in Radioecology: Abstract

AbstractThis report provides the first comprehensive and authoritative set of definitions for quantities, units and terms used in the highly interdisciplinary field of radioecology. The scope of th...

In radiological protection, the protection quantities should be expressed in terms of measurable physical quantities.

It is somewhat of a truism that is expressed in the often quoted statement that you can't go home again. In the days when life was simpler, we could assume that a measurement performed with a portable survey instrument yielding a value for exposure rate in terms of roentgens/hour was a sufficient approximation to the value for the dose equivalent rate or absorbed dose rate at a point in a radiation field. As our understanding of radiological protection grew more sophisticated, we found it necessary to introduce additional rigor into the definitions of the radiation protection quantities. As mentioned earlier, we demand a lot from the definitions of these quantities. They need to satisfy many conditions, perhaps too many. When they are examined from the point of view of a metrologist, they may be considered to be deficient in many respects. When they are viewed by a radiobiologist, they may appear to be naïve or overly simplistic. A radiation protection technologist at a nuclear power plant may have difficulty understanding their sometimes-subtle implications. The ICRU and ICRP have worked for quite some time to incorporate all the necessary requirements into the definitions of the operational and protection quantities. From the arguments of our debaters, one might conclude that after careful consideration of past developments, additional refinements will be devised in the future.

Glossary of Terms and Definitions of Quantities

Glossary of Terms and Definitions of Quantities

Glossary of Terms and Definitions of Quantities

Glossary of Terms and Definitions of Quantities

Definitions of electrical quantities commonly used in non‐sinusoidal conditions

AbstractThe analysis of electrical systems under non‐sinusoidal conditions has become an important topic in electrical engineering. Most of the approaches to the analysis and operation of electrical systems are undergoing a thorough revision, and several contributions concerning these topics can be found in the recent literature. However, in the development of this matter problems occur because of misunderstanding and misinterpretation mainly due to the terminology used by individual authors when referring to identical concepts and quantities. The present contribution considers the definitions of quantities that are frequently used for the analysis of non‐sinusoidal systems and formulates a technical‐scientifically sound document where these quantities and concepts are defined, a technical sound name is given, and a symbol is proposed for each quantity.

Remarks and suggestions on nomenclature and symbols in atmospheric optics

Having edited this special issue, which deals almost exclusively with the optics of atmospheric aerosols, I have learned that nomenclature and symbols are not standardized at all. A reader, although familiar with the field, may find it very difficult to understand a paper which uses a completely different nomenclature, and may have to make his own table of symbols and definitions in order to go through the paper. A survey of definitions used in applied physics and atmospheric sciences has demonstrated that even contradicting definitions for quantities frequently used in atmospheric optics do exist (Horvath and Pirich, 1983). Scientific life would be much easier if a consensus on the use of symbols and names could be attained. Obviously, a standardization has been desired by many scientists and most likely many working groups have made proposals. I would like to draw the reader’s attention to a publication by the International Association of Meteorology and Atmospheric Physics (IAMAP), Radiation Commission (Raschke 1978) which made a definite suggestion on which symbols and which words should be used in atmospheric optics. A selection of the ones appearing to be most significant in visibility research and a few more will be given below. The basis of all radiometric considerations is the radiant flux @, which is the radiant power or radiant energy per second, and given in watts. The radiant flux density d@/dA is the radiant flux do of any origin crossing a surface element dA divided by dA. Usually we differentiate between radiant flux density emerging in all directions from a surface which is called the radiant excitance* M = dD/dA, given in Wm-’ and the radiant flux from all directions incident on an surface element which is called the irradiance E=dO/dA which is also measured in Wm-‘. The radiance L = d2@/(dA.cos Q).dw of a surface in a direction Q is defined as the emitted flux per projected surface area and solid angle and is given in W m ’ sr’ Some difficulties arise when treating the radiance of a layer of aerosol or the sky, since a definite surface cannot be attributed to it. Middleton (1968) defines in this case the radiance by its effect

Aims and Goals of the ICRU and Other International Organisations with Respect to Patient Radiation Protection

After a short historical review, the goals of the ICRU are first presented: definition of quantities and units to be used in the field of ionising radiation, recommendations of measurement procedures for these quantities, definitions of terms and concepts, and investigation and selection of physical parameters. As far as the other international organisations are concerned, some of the main achievements are briefly presented for the IEC, UNSCEAR, ICRP, WHO, and IAEA. Besides technical developments and dosimetric intercomparisons, the importance of the education and of the continuous information of the radiologists is stressed. The role played by the CEC in education is recognised in the field of radiation protection in diagnostic radiology.

Aims and Goals of the ICRU and Other International Organisations with Respect to Patient Radiation Protection

After a short historical review, the goals of the ICRU are first presented: definition of quantities and units to be used in the field of ionising radiation, recommendations of measurement procedures for these quantities, definitions of terms and concepts, and investigation and selection of physical parameters. As far as the other international organisations are concerned, some of the main achievements are briefly presented for the IEC, UNSCEAR, ICRP, WHO, and IAEA. Besides technical developments and dosimetric intercomparisons, the importance of the education and of the continuous information of the radiologists is stressed. The role played by the CEC in education is recognised in the field of radiation protection in diagnostic radiology.

A critique of quantities used in radiation protection

It is argued that dose equivalent and effective dose equivalent are scientifically undesirable, are unstable, are largely unnecessary, are confusing, are potentially wasteful of radiobiological data, attempt to achieve the impossible and are abandoned when of greatest importance. It is stated that the place for judgemental factors is in the setting of limits, not in the definition of quantities. Proposals are made that absorbed dose, or a specially qualified absorbed dose, be used as the quantity in terms of which dose limits are set, and that different limits are laid down for high and low LET radiations.

Inventory of aggregates in an expanding urban area

Faced with a potential shortage of aggregate, the Minnesota Department of Transportation funded a study to inventory the aggregates in four pilot areas of the state and compare it with the estimated requirements in these areas. Based on the results of the study, several methods were suggested to enhance the aggregate supply in these areas. The aggregate resources in the four pilot areas were determined by analyzing the geology of the deposits, both natural aggregate and crushed rock. In addition, reserves in permitted properties were determined using a questionnaire that was given to each quarry operator in these areas. Permitted properties were defined as those for which permits have been issued by the government unit having jurisdiction. Analysis of the questionnaire date was supplemented with interviews of county and state highway department personnel and local planning agencies. Aggregate demand in the four areas was determined from national and county models of demand. Computer-aided multiple regression models defined the relationships between aggregate demand and construction of public and private facilities, ratio of non-metal to metal construction products, and the price of aggregate. Four methods were suggested for enhancing the aggregate supply. These included the definition of quantity and quality of aggregate in the vicinity of urban areas, improvement in beneficiation techniques to maximize the utilization of mined material, development of end-use specifications to permit maximum use of lower grade reserves and of recycled pavements, and revision of land use regulations to prevent the loss of aggregate reserves to urban sprawl.

Definitions of quantities and units

Definitions of quantities and units