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Gathering the Team
Published in Volker Knecht, AI for Physics, 2023
Lord Kelvin (1824–1907) and Rudolf Clausius (1822–88) formulated the law of conservation of energy. It is equivalent to the first law of thermodynamics stating the following: the change in the internal energy of a closed system is the heat supplied to the system minus the thermodynamic work done by the system on its surroundings. Kelvin and Clausius also stated the second law of thermodynamics implying that entropy (a measure of disorder) cannot decrease over time. Processes reversible in time (such as fluid flows in a well-designed turbine) are characterized by a constant entropy. In contrast, time-irreversible processes (such as the mixing of gases or fluids) occur along with an increase in entropy. The latter is often referred to as the concept of the arrow of time. Explaining this notion, as well as heat and in general the macroscopic behavior of nature (gases, fluids, or solids) from the behavior of large assemblies of microscopic entities (such as atoms or molecules), Ludwig Boltzmann (1844–1906) and Josiah Willard Gibbs (1839–1903) developed statistical mechanics, as a fundamentally new approach to science.10
Principles of Symbolization
Published in Terry A. Slocum, Robert B. McMaster, Fritz C. Kessler, Hugh H. Howard, Thematic Cartography and Geovisualization, 2022
Terry A. Slocum, Robert B. McMaster, Fritz C. Kessler, Hugh H. Howard
A ratio level of measurement has all the characteristics of the interval level plus a nonarbitrary zero point. Continuing with the temperature example, the Kelvin scale is ratio in nature because at 0°K molecular motion is minimized; thus, a temperature of 40°K is twice as warm as 20°K (in terms of the kinetic energy of the molecules). Ratio data sets are more common than interval data sets. For example, a perusal of the maps shown in this text will reveal that most are based on ratio-level data. Because many symbol forms can be used with both interval and ratio scales, these two levels of measurement are often grouped together and referred to as numerical data. The basic scales that we have discussed can also be divided into qualitative (nominal data) and quantitative (ordinal, interval, and ratio data) scales.1
Exergy analysis
Published in Kornelis Blok, Evert Nieuwlaar, Introduction to Energy Analysis, 2020
Kornelis Blok, Evert Nieuwlaar
There are several different formulations of the second law of thermodynamics. The Kelvin-Planck formulation reads: ‘It is impossible for any system to operate a thermodynamic cycle and deliver a net amount of energy by work to its surroundings while receiving energy by heat transfer from a single thermal energy reservoir’. In simple words: in practice, heat from a heat source cannot be fully converted into work by a thermodynamic cycle. Part of the heat will therefore end up in a heat sink in order to comply with the first law of thermodynamics (conservation of energy). This is represented in Figure 7.1 where heat from a heat source at elevated temperature is used in an ideal process (ideal thermodynamic work cycle) to produce work while releasing heat to a heat sink at lower temperature. The heat sink chosen here is the natural environment at environmental temperature Tref.
Risk preference evaluation – a fourth dimension of the application of the Laplace transform
Published in International Journal of Production Research, 2018
So, from now on, we may let denote any function belonging to this class of risk preference (utility) functions. This implies that no longer needs to be confined to the interval as a probability measure would require, but instead may take on any value depending on the point of zero a and the positive scale factor b. This scale is an interval scale, similar to a temperature scale (Celsius, Fahrenheit or Réaumur, but not Kelvin having an absolute point of zero, i.e. a ratio scale).
Invariance-based approach: general methods and pavement engineering case study
Published in International Journal of General Systems, 2021
Edgar Daniel Rodriguez Velasquez, Vladik Kreinovich, Olga Kosheleva
Sometimes, we can also select different starting points. Scale-scale-invariance assumes that we have a fixed starting point for measuring a quantity. This is true for most physical quantities, but for some physical quantities, we can select different starting points. For example, for measuring temperature, we can select, as a starting point, the temperature at which water freezes – and get the usual Celsius scale – or we can select the absolute zero and thus get the Kelvin scale. For different purposes, different starting points may be more appropriate.
Semiparametric Models for Accelerated Destructive Degradation Test Data Analysis
Published in Technometrics, 2018
Yimeng Xie, Caleb B. King, Yili Hong, Qingyu Yang
For temperature-accelerated processes, the Arrhenius model is often used to describe the relationship between the degradation and temperature. This model uses a transformed temperature level, which is given as Here, is in degrees Celsius, and the value 11,605 is the reciprocal of the Boltzmann’s constant (in units of eV). The value 273.16 in the denominator is used to convert to the Kelvin temperature scale.