Separate Regimes Research Articles

Navigating the legal uncertainty around the governance of an integrated energy system using the values of the energy transition and energy justice

AbstractIn order to realise the European Union's (EU) transition to clean and carbon‐neutral energy systems, various individual infrastructure systems and energy networks will have to coordinate and operate as an integrated energy system. Traditionally, these different infrastructure systems operate within their own sectors and are governed by separate legal regimes. The intersection of these different legal rules and interests creates regulatory uncertainty and risk for infrastructure operators and can dissuade operators from participating in system integration. This paper explores how infrastructure operators can overcome the legal uncertainty and regulatory risks of operating as an integrated system, whilst also ensuring that the policy objectives of the energy transition are realised. This paper argues that, by pursuing public values and energy justice principles, infrastructure operators will overcome the legal uncertainty surrounding system integration. By doing so, infrastructure operators will facilitate the realisation of an energy transition that is just, inclusive and in the public interest.

Changes in the European Union households' consumption structure and the sustainable development

The subject of this study is the relationship between the households' consumption structure changes and sustainable development. This research was conducted for the European Union (EU) countries in the years 2008-2020. Additionally, in the investigation, the considered area is divided into two separate regimes: countries that joined the EU before 2000 (referred to as Old EU Member States) and countries that joined the EU later (called New EU Member States). It is widely known that the territorial units in the first regime are relatively wealthier than those in the second group. As a result of differences in wealth between the defined regimes, consumer behaviours can vary. Sustainable consumption (SC) is one of the major aspects of sustainable development. SC indicates consumer choices that are both intentional and effective, and these choices demonstrate a positive impact on environmental and/or social conditions. In this research, the influence of households' consumption changes on the environmental pillar of sustainable development is evaluated. Caring for the natural environment is one of the main challenges today. In this research, another approach to measure environmental development is proposed. So far, different types of footprints have been used. This analysis considers most of the environmental indicators defined in the Sustainable Development Goals (SDG's). The environmental development of EU countries is evaluated based on the synthetic measure of development proposed by Hellwig. Moreover, the spatio-temporal sensitivity models are estimated and verified. The sensitivity parameter of these models shows the impact of consumption structure changes on environmental development, wherein the consumption structure is categorized into four groups of goods: services, non-durable, semi-durable, and durable. The spatial autoregressive (SAR) models are also estimated and verified. The investigation results point out the differences in the influence of consumption structure changes on sustainable development depending on the considered group of countries.

Neural network based two-phase flow classification in a vertical narrow rectangular channel

Flow Regimes in a vertical narrow rectangular channel of cross-section 20×1cm2 are investigated up-to wispy annular flow using a dense test matrix and double sensor conductivity probe at section mid point. The data from the probe is used to calculate void fraction, velocity of interfaces, and chord length of various flow structures. A five unit self organizing neural network is used to identify various flow regimes by using single point geometrical data of flow structures. Six separate flow regimes are found to exist. A new flow regime is identified and is called rolling-wispy flow. A discussion on boiling crisis is given regarding this flow regime. The resultant flow regime map is compared with various existing maps.

Competing gauge fields and entropically driven spin liquid to spin liquid transition in non-Kramers pyrochlores.

Gauge theories are powerful theoretical physics tools that allow complex phenomena to be reduced to simple principles and are used in both high-energy and condensed matter physics. In the latter context, gauge theories are becoming increasingly popular for capturing the intricate spin correlations in spin liquids, exotic states of matter in which the dynamics of quantum spins never ceases, even at absolute zero temperature. We consider a spin system on a three-dimensional pyrochlore lattice where emergent gauge fields not only describe the spin liquid behavior at zero temperature but crucially determine the system's temperature evolution, with distinct gauge fields giving rise to different spin liquid phases in separate temperature regimes. Focusing first on classical spins, in an intermediate temperature regime, the system shows an unusual coexistence of emergent vector and tensor gauge fields where the former is known from classical spin ice systems while the latter has been associated with fractonic quasiparticles, a peculiar type of excitation with restricted mobility. Upon cooling, the system transitions into a low-temperature phase where an entropic selection mechanism depopulates the degrees of freedom associated with the tensor gauge field, rendering the system spin-ice-like. We further provide numerical evidence that in the corresponding quantum model, a spin liquid with coexisting vector and tensor gauge fields has a finite window of stability in the parameter space of spin interactions down to zero temperature. Finally, we discuss the relevance of our findings for non-Kramers magnetic pyrochlore materials.

Cloud Susceptibility to Aerosols: Comparing Cloud‐Appearance Versus Cloud‐Controlling Factors Regimes

AbstractClouds can be classified into regimes based on their appearance or meteorological controlling factors. The cloud appearance regimes inherently include adjustments to aerosol effects, such as transitions between closed and open cells. Therefore, calculating cloud susceptibilities to aerosols for each cloud‐appearance regime individually and then aggregating them excludes much of the cloud adjustment component of the susceptibilities. In contrast, aggregating susceptibilities over regimes defined by cloud‐controlling factors includes the full effects of cloud adjustments. Here we compared the susceptibilities of the two kinds of cloud regimes and demonstrated this effect. Overall, increasing cloud droplet number concentration (Nd) consistently correlates to weaker precipitation, higher cloud fraction (CF), and reduced liquid water path, regardless of how the regime is defined. However, their susceptibilities to Nd aggregated over cloud‐appearance regimes are significantly lower than those aggregated over cloud‐controlling factors regimes, with lower‐tropospheric stability (LTS) serving as an example to define cloud‐controlling factors regimes. This underestimation is more pronounced for CF susceptibility, where the susceptibility for cloud appearance regimes is only 1/4 of the susceptibility for cloud controlling regimes. These findings imply that relying solely on cloud‐appearance regimes may underestimate the effective radiative forcing produced by cloud adjustment (ERFaci). Nevertheless, the substantial variability in the magnitude of cloud adjustment across appearance regimes at similar LTS also suggests that a single cloud‐controlling factor is not sufficient to fully separate cloud regimes to quantify cloud adjustment. Therefore, identifying a comprehensive set of cloud‐controlling factors is essential for accurately quantifying cloud adjustments in future studies.

Numerical simulation of flow characteristics in nonprismatic compound channels

ABSTRACT The assessment of the flow characteristics of river systems is a very intricate undertaking in the development of hydraulic models for the purposes of flood control and floodplain management. Therefore, it is essential to use simulation models in order to calibrate and verify the experimental results. In this study, the Hydrologic Engineering Centre's – River Analysis System (HEC-RAS) is used to calibrate and validate the distribution of velocity and shear stress for different converging compound channels. Two separate flow regimes were assessed for validation based on experimental data obtained from converging compound channels with angles of θ = 5°, 9°, and 12.38°. The projected values for two relative depths (β = 0.15 and 0.20) exhibit a similar pattern of variation as the empirical observations and are marginally lower than the recorded values. This suggests that the HEC-RAS model accurately estimates the velocity and shear stress values. The disparity between the simulated and experimental outcomes shows a discrepancy of less than 10%. Hence, the implications of our results suggest that while dealing with nonprismatic rivers, it is advisable to take into account lower values. The used methodology and the outcomes focused on problem-solving might potentially inform the development of flood control infrastructure for nonprismatic watercourses.

Through the Lens of the ICJ: Bridging the Gap between Human Rights and Humanitarian Norms in Global Child Soldiering

Recently in June 2022, the United Nations Special Representative of the Secretary-General for Children and Armed Conflict expressed that the ongoing use and recruitment of children in armed conflict globally warrants "international concern". Notwithstanding the existence of proscriptive norms in terms of international humanitarian law (IHL) and international human rights law (IHRL), international legal violations are nevertheless committed by states and non-state actors. A systematic analysis of the respective normative systems identifies a lacuna between specific provisions thereof. Consequently, violations are committed in armed conflicts for the purposes of IHRL but not IHL, it is contended that this inconsistency in the law perpetuates ongoing child soldiering. It is further contended that this inconsistency establishes a genus of children who are legally unprotected as they fall between the cracks of international law. Based on recent progressive jurisprudence of the International Court of Justice, an approach which will bridge the lacuna between these norms is proposed. Contrary to the view of the International Committee of the Red Cross and with due consideration for the lex specialis principle, it is proposed that the IHL and IHRL instruments should apply in a complementary fashion, as opposed to the separate legal regimes under which they have developed.

On the effect of flux-surface shaping on trapped-electron modes in quasi-helically symmetric stellarators

Using a novel optimization procedure, it has been shown that the Helically Symmetric eXperiment stellarator can be optimized for reduced trapped-electron-mode (TEM) instability [Gerard et al., Nucl. Fusion 63, (2023) 056004]. Presently, with a set of 563 experimental candidate configurations, gyrokinetic simulations are performed to investigate the efficacy of available energy EA, quasi-helical symmetry, and flux-surface shaping parameters as metrics for TEM stabilization. It is found that lower values of EA correlate with reduced growth rates, but only when separate flux-surface shaping regimes are considered. Moreover, configurations with improved quasi-helical symmetry demonstrate a similar reduction in growth rates and less scatter compared to EA. Regarding flux-surface shaping, a set of helical shaping parameters is introduced that show increased elongation is strongly correlated with reduced TEM growth rates, however, only when the quasi-helical symmetry is preserved. Using a newly derived velocity-space-averaged TEM resonance operator, these trends are analyzed to provide insights into the physical mechanism of the observed stabilization. For elongation, stabilization is attributed to geometric effects that reduce the destabilizing particle drifts across the magnetic field. Regarding quasi-helical symmetry, the TEM resonance in the maximally resonant trapping well is shown to increase as the quasi-helical symmetry is broken, and breaking quasi-helical symmetry increases the prevalence of highly resonant trapping wells. While these results demonstrate the limitations of using any single metric as a linear TEM proxy, it is shown that quasi-helical symmetry and plasma elongation are highly effective metrics for reducing TEM growth rates in helical equilibria.

Averaged Heat Fluxes Densities During Condensation and Evaporation of a Water Droplet

This study is intended for experimental investigation of the influence of boundary conditions on the intensity of phase transformations and heat transfer processes in a suspended water droplet. The results of the dynamics of the averaged heat fluxes densities during the droplet phase change cycle are presented and analysed. The influence of the droplet initial temperature, the surrounding air flow temperature and the additional humidity in the air flow were defined in separate regimes of the droplet phase transformations cycle. The experiments performed demonstrated that the parameters of the air flow surrounding the suspended water droplet affect the intensity of heat fluxes in the droplet throughout whole its phase change cycle. It was experimentally claimed that the initial temperature of the water droplet has no influence on the droplet heat and mass transfer processes in the equilibrium evaporation regime. The obtained results showed that most intensity heat flux densities are at the beginning of the droplet phase change cycle when condensation process occurs on the droplet’s surface in case with biggest amount of additional humidity in the surrounding air flow. This is very important in technologies of cleaning and heat recovery from flue gases.

Inflation regimes and hyperinflation: a Post-Keynesian/structuralist typology

Abstract The article proposes a typology of inflation regimes based on the Post-Keynesian and structuralist literature. We identify three separate regimes: the low, moderate and high inflation regimes. Hyperinflation is also defined and described. Each regime presents different characteristics. We identify the key role played by the distributive conflict between workers and capitalists in all the regimes, the role played by the indexation of wages on domestic prices in the moderate and high inflation regimes and the specific roles played by the widespread indexation on a short-term basis in the high inflation regime. Hyperinflation is explained by self-fulfilling prophecies about exchange rate variations and by the rejection of the domestic currency.

Thermo-chemical behaviour of Dunaliella salina biomass and valorising their biochar for naphthalene removal from aqueous rural environment

Thermo-chemical behavior of a microalgal biomass; Dunaliella salina was investigated through thermo-gravimetric analyses. Fully-grown D. salina biomass were subjected for biochar conversion using pyrolytic treatment at three distinct heating rates such as 2.5, 5, and 15 °C min−1. The kinetic appraisals were explained by using model-free kinetics viz., Kissinger-Akahira-Sanose, Flynn-Waal-Ozawa and Starink iso-conversional correlations with concomitant evaluation of activation energies (Ea). The Ea value is 194.2 kJ mol−1 at 90% conversion in FWO model, which is higher as compared to other two models. Moisture, volatile substances, and other biochemical components of the biomass were volatilized between 400 and 1000 K in two separate thermo-chemical breakdown regimes. Microscopic and surface characterization analyses were carried out to elucidate the elemental and morphological characteristics of the biomass and biochar. Further, the proficiency of the prepared biochar was tested for removing naphthalene from the watery media. The novelty of the present study lies in extending the applicability of biochar prepared from D. salina for the removal of a model polyaromatic hydrocarbon, naphthalene.

Ideal fracton superfluids

We investigate the thermodynamics of equilibrium thermal states and their near-equilibrium dynamics in systems with fractonic symmetries in arbitrary curved space. By explicitly gauging the fracton algebra we obtain the geometry and gauge fields that field theories with conserved dipole moment couple to. We use the resultant fracton geometry to show that it is not possible to construct an equilibrium partition function for global thermal states unless part of the fractonic symmetries is spontaneously broken. This leads us to introduce two classes of fracton superfluids with conserved energy and momentum, namely pp-wave and ss-wave fracton superfluids. The latter phase is an Aristotelian superfluid at ideal order but with a velocity constraint and can be split into two separate regimes: The U(1) fracton superfluid and the pinned ss-wave superfluid regimes. For each of these classes and regimes we formulate a hydrodynamic expansion and study the resultant modes. We find distinctive features of each of these phases and regimes at ideal order in gradients, without introducing dissipative effects. In particular we note the appearance of a sound mode for ss-wave fracton superfluids. We show that previous work on fracton hydrodynamics falls into these classes. Finally, we study ultra-dense pp-wave fracton superfluids with a large kinetic mass in addition to studying the thermodynamics of ideal Aristotelian superfluids.

Ni‐Catalyzed Regio‐ and Enantioselective Homoallylic Coupling: Synthesis of Chiral Branched 1,5‐Dienes Featuring a Quaternary Stereogenic Center and Mechanistic Analysis

AbstractAsymmetric synthesis of small molecules comprising quaternary stereogenic carbon centers represents a challenging objective. Here regio‐ and enantioselective synthesis of chiral 1,5‐dienes featuring quaternary stereocenters is reported via nickel‐promoted by reductive homoallylic coupling. The developed methodology features an atypical preference for the formation of unusual branched regioisomers (rr >20 : 1) in a sterically challenging allylic substitution event and furnishes the products with enantiomeric ratios of up to 98 : 2 and with high chemo‐ and E‐selectivity. A range of experimental evidences suggest that zinc plays a dual role to generate electrophilic and nucleophilic Ni(II)‐allyl intermediates empowering a unique formal bimetallic cross‐electrophile manifold in two separate kinetic regimes.

Ni-Catalyzed Regio- and Enantioselective Homoallylic Coupling: Synthesis of Chiral Branched 1,5-Dienes Featuring a Quaternary Stereogenic Center and Mechanistic Analysis.

Asymmetric synthesis of small molecules comprising quaternary stereogenic carbon centers represents a challenging objective. Here regio- and enantioselective synthesis of chiral 1,5-dienes featuring quaternary stereocenters is reported via nickel-promoted by reductive homoallylic coupling. The developed methodology features an atypical preference for the formation of unusual branched regioisomers (rr >20 : 1) in a sterically challenging allylic substitution event and furnishes the products with enantiomeric ratios of up to 98 : 2 and with high chemo- and E-selectivity. A range of experimental evidences suggest that zinc plays a dual role to generate electrophilic and nucleophilic Ni(II)-allyl intermediates empowering a unique formal bimetallic cross-electrophile manifold in two separate kinetic regimes.

Universal scaling of shear thickening transitions

Nearly, all dense suspensions undergo dramatic and abrupt thickening transitions in their flow behavior when sheared at high stresses. Such transitions occur when the dominant interactions between the suspended particles shift from hydrodynamic to frictional. Here, we interpret abrupt shear thickening as a precursor to a rigidity transition and give a complete theory of the viscosity in terms of a universal crossover scaling function from the frictionless jamming point to a rigidity transition associated with friction, anisotropy, and shear. Strikingly, we find experimentally that for two different systems—cornstarch in glycerol and silica spheres in glycerol—the viscosity can be collapsed onto a single universal curve over a wide range of stresses and volume fractions. The collapse reveals two separate scaling regimes due to a crossover between frictionless isotropic jamming and frictional shear jamming, with different critical exponents. The material-specific behavior due to the microscale particle interactions is incorporated into a scaling variable governing the proximity to shear jamming, that depends on both stress and volume fraction. This reformulation opens the door to importing the vast theoretical machinery developed to understand equilibrium critical phenomena to elucidate fundamental physical aspects of the shear thickening transition.

A theory of rheological film condensation

The article provides a theoretical investigation of the laminar film-condensation of shear-thinning fluids onto an isothermal, vertical plate in the presence of gravity, interfacial shear, wall friction, and inertia. The liquid motion occurs toward gravity, overcoming the resistances of interfacial shear, wall friction, and inertia. The liquid motion induces momentum to the adjacent stagnant saturated vapor by interfacial shear. The vapor motion, in turn, influences the liquid film’s heat transfer and fluid dynamics. For film condensation, it is well-known that the film, along the length of the plate, can be grouped in two separate heat transfer regimes, viz. conduction-dominated regime and convection-dominated regime. For the first time, we have identified three distinct fluid dynamic regions across the film (viz. R1, R2, and R3) unique to power-law fluids. R1 is bounded between the condensing surface and the locus of Newtonian shear stress. R2 is bounded between the locus of Newtonian shear stress and the locus of zero shear stress. Beyond R2, R3 is stretched up to the liquid-vapor interface. The transverse temperature gradient is subtly different in these three fluid dynamic regions. We examine flow physics on a non-dimensional platform. The critical role of the power-law index in determining wall-friction and condensate’s mass flow rate and the impact of liquid Prandtl number in achieving the degree of subcooling has been nicely illustrated. We expose various limiting conditions for simplifying the robust mathematical theory. An analytical expression for the liquid’s longitudinal velocity has been derived, neglecting inertia and interfacial shear.

Understanding molecular abundances in star-forming regions using interpretable machine learning

ABSTRACT Astrochemical modelling of the interstellar medium typically makes use of complex computational codes with parameters whose values can be varied. It is not always clear what the exact nature of the relationship is between these input parameters and the output molecular abundances. In this work, a feature importance analysis is conducted using SHapley Additive exPlanations (SHAP), an interpretable machine learning technique, to identify the most important physical parameters as well as their relationship with each output. The outputs are the abundances of species and ratios of abundances. In order to reduce the time taken for this process, a neural network emulator is trained to model each species’ output abundance and this emulator is used to perform the interpretable machine learning. SHAP is then used to further explore the relationship between the physical features and the abundances for the various species and ratios we considered. H2O and CO’s gas phase abundances are found to strongly depend on the metallicity. NH3 has a strong temperature dependence, with there being two temperature regimes (<100 K and >100 K). By analysing the chemical network, we relate this to the chemical reactions in our network and find the increased temperature results in increased efficiency of destruction pathways. We investigate the HCN/HNC ratio and show that it can be used as a cosmic thermometer, agreeing with the literature. This ratio is also found to be correlated with the metallicity. The HCN/CS ratio serves as a density tracer, but also has three separate temperature-dependence regimes, which are linked to the chemistry of the two molecules.

Air quality and comfort constrained energy efficient operation of multi-zone buildings

Maintaining indoor air quality (IAQ) through effective ventilation is essential for the well-being and productivity of building occupants. Control strategies aimed at improving the efficiency of heating, ventilation and air conditioning (HVAC) systems must jointly determine ventilation and heating and cooling processes. In this paper, we study the problem of minimizing the energy consumption of the HVAC system in a multi-zone building, while meeting thermal comfort and IAQ requirements. We first perform a steady state analysis of the zonal carbon dioxide (CO2) concentration and the temperature dynamics. The resulting expressions are convex in the zonal mass flow rates and zonal temperatures. Guided by the steady state solutions for meeting the thermal comfort constraints, we develop two control policies for improving the energy efficiency of building HVAC systems while jointly satisfying indoor temperature and IAQ constraints. We compare the performance of our proposed approaches with those of multiple baseline approaches which implement separate regimes for controlling zonal temperature and IAQ for a typical work-day in a multi-zone campus building. We have evaluated the performance of our proposed approaches under varying levels of flexibility in zonal temperatures. We have shown that zonal temperature flexibility can result in energy savings up to 32% (for the same control strategies) as compared to the case where no such flexibility is permitted. Our proposed approaches were seen to offer potential savings of nearly 29% compared to the baseline.

Paleostress analysis and rift kinematics of the petroliferous Barmer rift basin, western Rajasthan, India

The NW-trending Barmer rift in western Rajasthan is one of the major petroliferous Indian basins. The basin rifted twice: (i) NW – SE extension in Early Cretaceous, and (ii) NE – SW extension during Late Maastrichtian to Early Paleogene. We performed structural fieldwork mainly along the rift margins to decipher the rift kinematics through geologic time. We collected ∼500 fault-slip data from limited outcrops along the basin's western and eastern margins. Paleostress analysis was performed for the first time in this basin using Win_Tensor, T-Tecto and FaultKin software. The outcome of this analyses shows that a strike-slip stress regime was prevalent in the western rift margin whereas the eastern margin experienced extension to transtension. Four paleostress regimes, DΔ, Dα, DΦ, and Dβ, were identified by inverting the fault-slip data. The two separate extensional regimes, during the Early Cretaceous and in the Late Maastrichtian to Early Paleogene, are confirmed. These are Dα (NW – SE extension) and Dβ (NE – SW extension). The analysis also presents two strike-slip regimes with varying maximum horizontal stress (SHMax) orientation, viz. DΔ and DΦ. Exact age correlation for these strike-slip regimes remains indeterminate. However, we deduced DΔ and DΦ were associated with the first extensional phase (Dα) during Early Cretaceous linked to India – Madagascar oblique separation. The Barmer rift extended obliquely guided by pre-existing structures. Remote sensing image analysis indicates that part of the western margin is neotectonically active as inferred from the drainage morphometry. The stress inversion analysis of earthquake focal mechanism data depicts a strike-slip transpressive regime prevailing at present in the NW India along with ∼ N-trending SHMax. This is mainly responsible for the neotectonic activities in the basin. We documented several fault gouge zones along moderately-dipping faults in the Cretaceous outcrops at the eastern margin. The lower the fault dips, the thicker the gouge zones associated with the faults. Such thick fault gouge of around 100 cm or more may act as a structural fault bound trap for Cretaceous reservoirs at depth. (Words: 324).

Threshold Effect of Remittance Inflows on Selected Macroeconomic Variables in Nigeria

The study examines the threshold effect of remittance inflows and also investigates the channels through which remittances affect macroeconomic variables in Nigeria. The study selected two macroeconomic variables—output growth and inflation rate. This was done to evaluate the proposition that an economy can experience both the positive and negative effect of remittance inflows over time. The study employs the use of annual secondary data spanning from 1986 to 2019 on variables of interest. Analysis was done using the threshold regression technique, vector error correction and Granger causality. A single threshold value was obtained for both inflation and output models, which led to splitting the models into two separate regimes. The study discovered that remittance inflows in Nigeria are large enough to significantly influence key macroeconomic variables and that private consumption, money supply and interest rate are the channels through which remittances affect macroeconomic variables. The study, therefore, concludes that the best way to maximise remittance inflows within the Nigerian economy is to effectively engage inflows in productive investments.