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Entropy economics : the living basis of value and production
\"Economists dream of equilibrium. It's time to wake up. In mainstream economics, markets are ideal if competition is perfect. When supply balances demand, economic maturity is orderly and disturbed only by shocks. These ideas are rooted in doctrines going back thousands of years yet, as James K. Galbraith and Jing Chen show, they contradict the foundations of our scientific understanding of the physical and biological worlds. Entropy Economics discards the conventions of equilibrium and presents a new basis for thinking about economic issues, one rooted in life processes--an unequal world of unceasing change in which boundaries, plans, and regulations are essential. Galbraith and Chen's theory of value is based on scarcity, and it accounts for the power of monopoly. Their theory of production covers increasing and decreasing returns, uncertainty, fixed investments over time, and the impact of rising resource costs. Together, their models illuminate key problems such as trade, finance, energy, climate, conflict, and demography. Entropy Economics is a thrilling framework for understanding the world as it is and will be keenly relevant to the economic challenges of a world threatened with disorder\"-- Provided by publisher.
BOOK
Integrating Maximum Entropy Production Theory and Machine Learning to Improve Global Evapotranspiration Modeling
Accurate estimation of terrestrial evapotranspiration (ET) is vital for understanding global water and energy cycles. However, current global ET estimations are not well constrained. This study introduces an integrated framework combining the Maximum Entropy Production (MEP) theory with Random Forest (RF) model to improve global ET estimation. Specifically, in contrast to direct ET estimation by the RF model, the integrated framework (MEP‐RF) trains to predict error of MEP‐simulated ET. MEP‐RF outperforms RF in spatiotemporal extrapolation. Attribution analysis with in situ observations reveals that the inputs of MEP are the most critical variables for the ET process, including net radiation, vegetated area, soil moisture, and surface temperature. We further drive MEP‐RF with global reanalysis and satellite data sets of these four inputs, yielding a global mean terrestrial ET of 548 mm/year, with 77% attributed to transpiration. The global ET increased at a rate of 0.85 mm/year per year during 2003–2021, primarily due to vegetation greening rather than rising temperature, while decreasing soil moisture led to decreasing regional ET. The integrated framework provides a novel approach for the estimation of global ET without the need for hard‐to‐obtain and thus uncertain inputs, such as wind speed, surface roughness, aerodynamic and canopy stomatal resistance. Therefore, MEP‐RF offers an independent method on existing global ET products. It represents a promising physically based approach that can be incorporated into Earth System Models to enhance water and energy cycle simulations.
Journal Article
Complementary Relationship Among Heat Flux Ratios and Maximum Entropy Production Principle in Humid Forests
Understanding how the net Solar radiation is partitioned into heat fluxes on land surface is fundamental to understand water, energy, and carbon cycles. Here we claim that, in forests under energy‐limited environment, the proportion in the net radiation occupied by the sum of the sensible and latent heat fluxes rarely varies over time; the variability in the latent heat fraction is mostly compensated by that of the sensible heat flux. This mutual compensation is rooted in the energy conservation principle and also in accordance with the principle of Maximum Entropy Production (MEP). The ratio of inertia parameters corresponding to latent and sensible heat fluxes in the MEP‐based model, is found approximately the reciprocal Bowen ratio. With this seesaw relationship, the formulation of the MEP‐based model for the surface energy partitioning problem is simplified. The new formulation is tested for a wide range of flux tower sites with different biome, demonstrating promising results. Plain Language Summary The Sun is the primary energy source to the Earth and it is important to understand how sunlight converts to different types of heat fluxes on the ground. We claim that the more heat used to warm up the air, the less spent for turning water into vapor, and vice versa. As a result, the proportion of two types of heats to the net Solar energy is constant. This idea can be utilized to make a simpler way to calculate the amount of heat fluxes. Simulation results nicely agree with measurements. Key Points Energy conservation implies the complementary relationship among heat flux ratios to net radiation The complementary relationship is in accordance with the maximum entropy production principle With the complementary relationship, a simple method for surface energy partitioning is proposed
Journal Article
The Entropy of Entropy: Are We Talking about the Same Thing?
In the last few decades, the number of published papers that include search terms such as thermodynamics, entropy, ecology, and ecosystems has grown rapidly. Recently, background research carried out during the development of a paper on “thermodynamics in ecology” revealed huge variation in the understanding of the meaning and the use of some of the central terms in this field—in particular, entropy. This variation seems to be based primarily on the differing educational and scientific backgrounds of the researchers responsible for contributions to this field. Secondly, some ecological subdisciplines also seem to be better suited and applicable to certain interpretations of the concept than others. The most well-known seems to be the use of the Boltzmann–Gibbs equation in the guise of the Shannon–Weaver/Wiener index when applied to the estimation of biodiversity in ecology. Thirdly, this tendency also revealed that the use of entropy-like functions could be diverted into an area of statistical and distributional analyses as opposed to real thermodynamic approaches, which explicitly aim to describe and account for the energy fluxes and dissipations in the systems. Fourthly, these different ways of usage contribute to an increased confusion in discussions about efficiency and possible telos in nature, whether at the developmental level of the organism, a population, or an entire ecosystem. All the papers, in general, suffer from a lack of clear definitions of the thermodynamic functions used, and we, therefore, recommend that future publications in this area endeavor to achieve a more precise use of language. Only by increasing such efforts it is possible to understand and resolve some of the significant and possibly misleading discussions in this area.
Journal Article
Analysis of Flow Loss Characteristics of a Multistage Pump Based on Entropy Production
To reveal the internal flow loss characteristics of a multi-stage pump, the unsteady calculation of the internal flow field of a seven-stage centrifugal pump was carried out, and the entropy production theory and Q criterion were utilized to analyze the unsteady flow characteristics of each flow component under different flow rates. The research results show that as the flow rate increases, the entropy production value and the energy loss inside the flow components also increase accordingly. The viscous dissipation entropy production caused by fluid viscosity is very small, and the turbulent dissipation entropy production caused by turbulent fluctuations and wall dissipation entropy production are the main sources of energy loss. The impellers, diffusers, and outlet chamber are the main regions of energy loss in the multistage pump. The entropy production value of the first-stage impeller is significantly higher than that of other impellers, while the entropy production value of the first-stage diffuser is significantly lower than that of other diffusers. Through vortex structure analysis, it is found that the high entropy production regions in the impeller are concentrated in the impeller inlet area, the blade suction surface, and the impeller outlet area.
Journal Article
Shaped-Charge Learning Architecture for the Human–Machine Teams
In spite of great progress in recent years, deep learning (DNN) and transformers have strong limitations for supporting human–machine teams due to a lack of explainability, information on what exactly was generalized, and machinery to be integrated with various reasoning techniques, and weak defense against possible adversarial attacks of opponent team members. Due to these shortcomings, stand-alone DNNs have limited support for human–machine teams. We propose a Meta-learning/DNN → kNN architecture that overcomes these limitations by integrating deep learning with explainable nearest neighbor learning (kNN) to form the object level, having a deductive reasoning-based meta-level control learning process, and performing validation and correction of predictions in a way that is more interpretable by peer team members. We address our proposal from structural and maximum entropy production perspectives.
Journal Article
Energy Characteristics of a Bidirectional Axial-Flow Pump with Two Impeller Airfoils Based on Entropy Production Analysis
This research sought to determine the spatial distribution of hydraulic losses for a bidirectional axial-flow pump with arc- and S-shaped impellers. The unsteady Reynolds time-averaged Stokes (URANS) approach with the SST k-omega model was used to predict the internal flow field. The total entropy production (TEP) and total entropy production rate (TEPR) were used to evaluate the overall and local hydraulic losses. The results show that the distribution of TEP and TEPR was similar for both impeller cases. Under a forward condition, TEP mainly comes from the impeller and elbow pipe. The high TEPR inside the impeller can be found near the shroud, and it shifts from the leading edge to the trailing edge with an increase in the flow rate due to the decline in the attack angle. The high TEPR inside the elbow pipe can be seen near the inlet, and the area shrinks with an increase in the flow rate caused by a reduction in the velocity circulation. Under the reverse condition, TEP mainly comes from the impeller and the straight pipe. The TEPR of the region near the shroud is obviously higher than for other regions, and the area of high TEPR near the suction side shrinks with an increase in the flow rate. The high TEPR of the straight pipe can be found near the inlet, and declines in the flow direction. These results provide a theoretical reference for future work to optimize the design of the bidirectional axial-flow pump.
Journal Article
Foraging Dynamics and Entropy Production in a Simulated Proto-Cell
All organisms depend on a supply of energetic resources to power behavior and the irreversible entropy-producing processes that sustain them. Dissipative structure theory has often been a source of inspiration for better understanding the thermodynamics of biology, yet real organisms are inordinately more complex than most laboratory systems. Here we report on a simulated chemical dissipative structure that operates as a proto cell. The simulated swimmer moves through a 1D environment collecting resources that drive a nonlinear reaction network interior to the swimmer. The model minimally represents properties of a simple organism including rudimentary foraging and chemotaxis and an analog of a metabolism in the nonlinear reaction network. We evaluated how dynamical stability of the foraging dynamics (i.e., swimming and chemotaxis) relates to the rate of entropy production. Results suggested a relationship between dynamical steady states and entropy production that was tuned by the relative coordination of foraging and metabolic processes. Results include evidence in support of and contradicting one formulation of a maximum entropy production principle. We discuss the status of this principle and its relevance to biology.
Journal Article
A Thermodynamic Closure Model for Titan’s Surface Temperature: Its Long-Term Stability Anchored to Methane’s Triple Point
We develop a minimal thermodynamic model to predict Titan’s surface temperature based on radiative–convective equilibrium and the principle of maximum entropy production (MEP). The model retains only the essential atmospheric constituents: gaseous methane, which absorbs both longwave and near-infrared radiation, and stratospheric haze, which scatters and absorbs solar flux. Subject to Clausius–Clapeyron scaling of methane vapor pressure together with energy balances at the surface, tropopause, and stratopause, the model links the convective flux to the surface temperature, which exhibits a pronounced maximum due to competing radiative effects of tropospheric methane. As the surface warms, enhanced greenhouse effect would strengthen the convection, whereas the rising anti-greenhouse effect would suppress convection. The resulting convective peak corresponds to MEP, which thus selects a surface temperature slightly above methane’s triple point. To assess its long-term evolution, we consider a 20% dimmer early Sun and a hypothetical 20% enrichment of the oceanic methane. Even in combination, they only cool the surface by ~2 K, in sharp contrast to the ~20 K cooling inferred in studies that prescribe haze abundance. This study suggests a critical role of self-adjusting haze in providing the internal degree of freedom necessary for MEP closure, thereby stabilizing Titan’s temperature.
Journal Article
Vortex Evolution and Energy Production in the Blade Channel of a Francis Turbine Operating at Deep Part Load Conditions
The blade vortex evaluation in Francis Turbine under deep part load conditions generates severe pressure fluctuations in the runner. The complex flow in a model turbine is numerically investigated based on a modified Partially Averaged Navier-Stokes method. The main emphasis is focused on revealing the correlation mechanism of blade vortex evolution and energy production. The results indicate that the modified PANS method shows significant advantages in hydro turbine’s simulation than the traditional RANS method. At deep part load conditions, the vorticity formed at the leading edge of the suction surface and the trailing edge of the pressure surface in the blade channels. The stretching term provides the most vorticity increments while the dilation term inhibiting part which only provides a decrement of the vorticity evolution. Based on the entropy production theory, the total entropy production distribution is consisting with the distribution of vorticity. At deep part load condition, direct dissipation and turbulent dissipation provide the most entropy, while at part load condition the proportion of these two-part decreased.
Journal Article