Dominant Scale Research Articles

Coherent structures detection within a dense Alpine forest

The influence of coherent vortices on the turbulence structure above and below a dense plant canopy is investigated using turbulence measurements collected at five levels on top and inside a coniferous forest on an Alpine Plateau. Five different stability regimes, from free convection to very stable stratification, were identified and considered in the analysis. Coherent structures are detected by fitting the vertical velocity auto-correlation functions with a theoretical oscillating function. This allowed to evaluate the coherent vortices characteristic timescales and to discriminate between turbulent data subsets characterized by fine-scale turbulence and subsets in which turbulence is dominated by coherent structures generated at the canopy top. An original methodology to fit cross-correlation function and to single out the most energetic frequency in presence of periodic behaviour is presented and applied to the turbulent momentum flux. The analysis shows how not far from neutral conditions the dominant time scale of the momentum flux is mainly determined by the longitudinal wind velocity component, rather than vertical one, while in free convection and very stable conditions coherent vortices do not seem to influence the momentum transport, dominated by large-scale structures. This is confirmed by the fine-scale turbulence and coherent structures efficiency in turbulence transport throughout the stability regimes.

Matching method between nanoparticle displacement agent size and pore throat in low permeability reservoir

Nano-particles possess desirable attributes such as small particle size, excellent injectivity, and migration performance, making them highly compatible and adaptable for addressing the water flooding requirements of the low-permeability oil reservoir. When selecting an oil displacement agent for enhancing water flooding and improving oil recovery, factors such as injectivity and migration need to be carefully considered. In this study, through a comprehensive analysis of the mechanism and technical characteristics of nano-particle oil displacement agents, the plugging and profile control mechanisms recognized by the mainstream of nano-particles are elucidated. By examining various elements including outcrop fractures, natural micro-fractures, artificial support fractures, and dynamic monitoring data, a reevaluation of the dominant channel scale governing water drive in low permeability reservoirs is conducted, thereby defining the target entities for profile control and flooding operations. Drawing upon Darcy’s percolation law and leveraging enhanced oil recovery techniques based on the classical Kozeny equation, a profile control and flooding mechanism is proposed that focuses on increasing the specific surface area of polymer particles while simultaneously reducing reservoir permeability. This innovative approach establishes a novel matching method between nano-polymer particles and the diverse media found within the reservoir. Lastly, the application of nanoparticle flooding technology in Changqing Oilfield is presented, highlighting its practical implementation and benefits.

Dipolar quantum solids emerging in a Hubbard quantum simulator.

In quantum mechanical many-body systems, long-range and anisotropic interactions promote rich spatial structure and can lead to quantum frustration, giving rise to a wealth of complex, strongly correlated quantum phases1. Long-range interactions play an important role in nature; however, quantum simulations of lattice systems have largely not been able to realize such interactions. A wide range of efforts are underway to explore long-range interacting lattice systems using polar molecules2-5, Rydberg atoms2,6-8, optical cavities9-11 or magnetic atoms12-15. Here we realize novel quantum phases in a strongly correlated lattice system with long-range dipolar interactions using ultracold magnetic erbium atoms. As we tune the dipolar interaction to be the dominant energy scale in our system, we observe quantum phase transitions from a superfluid into dipolar quantum solids, which we directly detect using quantum gas microscopy with accordion lattices. Controlling the interaction anisotropy by orienting the dipoles enables us to realize a variety of stripe-ordered states. Furthermore, by transitioning non-adiabatically through the strongly correlated regime, we observe the emergence of a range of metastable stripe-ordered states. This work demonstrates that novel strongly correlated quantum phases can be realized using long-range dipolar interactions in optical lattices, opening the door to quantum simulations of a wide range of lattice models with long-range and anisotropic interactions.

Classification of Turbulent Mixing Driven Sources in Marine Atmospheric Boundary Layer With Use of Shipborne Coherent Doppler Lidar Observations

AbstractA method to identify the turbulent mixing sources within the marine atmospheric boundary layer (MABL) based on the shipborne coherent Doppler lidar measurements is introduced in this paper. Combining with the coherent Doppler lidar signal‐to‐noise ratio, vertical velocity skewness, turbulence kinetic energy dissipation rate, and wind shear intensity, the categories of turbulent mixing sources and the specific turbulent mixing sources could be determined. The method is applied into two voyages of MABL observation during May 2021 in the South China Sea and during April 2022 in the Bohai Sea and Yellow Sea. The turbulent mixing processes are captured and the classification of the turbulence driven sources within the MABL are realized. The temporal‐spatial evolution characteristics of the turbulence mixing process in the MABL are investigated under different weather conditions containing clear‐sky day, cloudy‐sky day, and sea‐fog day. The convective mixing process is recognized in the daytime of the clear‐sky day and the intermittent cloud‐driven turbulence exists below the cloud layer. Additionally, the turbulent mixing is weak which could not act as the main driven source during the sea‐fog day. Furthermore, the dominant turbulence scale analyses of different turbulence sources are conducted based on the cospectra of the vertical velocity and the horizontal speed measurements. The turbulence parameters of different turbulence sources are statistical analyzed and compared in different sea areas. The classification method has the broad application prospects on the study of the air‐sea interaction.

Resonant enhancement of photo-induced superconductivity in K3C60

Photo-excitation at terahertz and mid-infrared frequencies has emerged as an effective way to manipulate functionalities in quantum materials, in some cases creating non-equilibrium phases that have no equilibrium analogue. In K3C60, a metastable zero-resistance phase was observed that has optical properties, nonlinear electrical transport and pressure dependencies compatible with non-equilibrium high-temperature superconductivity. Here we demonstrate a two-orders-of-magnitude increase in photo-susceptibility near 10 THz excitation frequency. At these drive frequencies, a metastable superconducting-like phase is observed up to room temperature. The discovery of a dominant frequency scale sheds light on the microscopic mechanism underlying photo-induced superconductivity. It also indicates a path towards steady-state operation, limited at present by the availability of a suitable high-repetition-rate optical source at these frequencies.

Initial cyclostratigraphy of the middle Nama Group (Schwarzrand Subgroup) in southern Namibia

The Ediacaran Period includes critical evolutionary trends of early complex life as well as climatic variations associated with ocean oxygenation, glaciations, and carbon cycling, which are still poorly understood in terms of astronomical climate forcing. The middle Nama Group in southern Namibia was deposited during the late Ediacaran in mainly shallow marine environments within a foreland basin and consists of hierarchically arranged depositional sequences. Here, we test a possible astronomical origin of these sedimentary variations by developing an initial cyclostratigraphic framework based on satellite images integrated with recently published high-precision U-Pb zircon ages. Regular sedimentary alternations occur dominantly on scales of several tens of meters, accompanied by smaller- and larger-scale variations, and are correlatable over distances of ∼50 km. Throughout the studied succession, 35 to 39 alternations are recognized on this dominant scale, which have an average duration of ∼120–180 k.y. This duration corresponds well with the period of short eccentricity (∼100 k.y.), given the likely presence of hiatuses, or alternatively, the period of obliquity amplitude modulation (∼173 k.y.), which would imply no time is missing on this scale. The dominant alternations are consistent with previously identified medium-scale sequences in this succession, which have been interpreted to record fluctuations in relative or eustatic sea level. We hypothesize that astronomically-forced fluctuations in eustatic sea level modulated deposition of the middle Nama Group. Geochemical studies suggested a relation between fossil distribution, redox variability and sea level, implying that astronomical forcing may have played a role in the distribution of early complex life.

Identifying dominant flow features from very-sparse Lagrangian data: a multiscale recurrence network-based approach

Realistic fluid flow problems often require that Lagrangian tracers are deployed in a sparse or very-sparse manner, such as for oceanic and atmospheric flows where large-scale motion needs characterisation. Data sparsity represents a significant issue in Lagrangian analysis, especially for data-driven methods that rely heavily on large datasets. We propose a multiscale spatial recurrence network (MSRN) methodology for characterising very-sparse Lagrangian data, which exploits individual tracks and a spatial recurrence criterion to identify the spatio-temporal complexity of tracer trajectories. The MSRN is an unsupervised modelling framework that does not require a priori parameter setting, and—through the quantification of persistent link activation at specific trajectory intervals—can reveal the presence of dominant looping scales in a variety of salient fluid flows. This new paradigm is shown to be successful for the study of Lagrangian tracers seeded in complex (realistic) flows, including unsteady and advection-dominated problems. This makes MSRNs an effective and versatile tool to characterise sensor trajectories in key problems such as environmental processes critical to understanding and mitigating climate change.Graphic abstract

Unveiling the Core Patterns of High-Latitude Electron Density Distribution at Swarm Altitude

The ionosphere has distinctive characteristics under different solar and geomagnetic conditions, as well as throughout the seasons, and has a direct impact on our technological life in terms of radio communication and satellite navigation systems. In the pursuit of developing highly accurate ionospheric models and/or improving existing ones, understanding the various physical mechanisms that influence electron density dynamics is critical. In this study, we apply the Multivariate Empirical Mode Decomposition (MEMD) method to the electron density distribution in the mid-to-high latitude (above 50° magnetic latitude) regions in order to identify the dominant scales at which these mechanisms operate. The data were collected by the Swarm mission in the Northern Hemisphere. MEMD allows us to separate the main intrinsic modes and assess their relative contributions to the original one, thereby identifying the most important modes and the spatial scales at which they exert influence. Our study spanned the period from 1 January 2016 to 31 December 2021, which was characterized by low solar activity levels. This choice allowed for a more focused investigation of other variables influencing electron density distribution under similar solar activity conditions. We specifically examined the variations of the resulting modes in relation to different seasons and geomagnetic activity conditions, providing valuable insights into the complex behavior of the ionosphere in response to various external factors.

Effect of acoustic metasurface on hypersonic-boundary-layer wave packet

Effect of the acoustic metasurface on a broadband wave packet in a Mach 6 boundary layer is studied. Direct numerical simulations (DNSs) with time-domain impedance boundary condition (TDIBC) and metasurface with microstructures are performed. It is shown that DNS with TDIBC resolves the amplitude and phase information of the wave packet satisfactorily. The minor prediction discrepancy arises from the modeling error in the acoustic impedance. The interesting finding of this paper is that the metasurface behaves as an equivalent unsteady blowing-suction model to perturb the wall-normal velocity and then passively the pressure field. Although both pressure and wall-normal velocity appear in the characteristic-wave variable, the pressure can be decoupled to be updated by the Neumann condition, as usually employed in Navier–Stokes solvers. The dominant frequency scale that enables reproducing the stabilization effect of the metasurface is found to be slightly smaller than the energetic frequency maximum of the wave packet. This observation indicates that the high-frequency unsteadiness nature of the blowing-suction behavior is indispensable, which is induced by the interaction of the metasurface and the wave packet. For the stabilization mechanism, energy analysis reveals that a dilatation-related work near the wall is significantly suppressed by the metasurface, which agrees with the wall-normal location where the wave-packet fluctuation gets attenuated.

Modelling the Potential Long-Range Dispersion of Atmospheric Microplastics Reaching a Remote Site

The study of the microplastic dispersion in the atmosphere is a relatively new field of research. In the studies available in literature, it was suggested that long-range transport may play a main role in the motion of microplastics towards remote sites, where no significant local sources are present. In this framework, here the Lagrangian particle dispersion model MILORD was used in the backward mode to investigate the potential long-range dispersion of microplastics in the atmosphere and to assess possible source areas that may determine microplastic pollution in a remote site. The chosen case study refers to the work of Allen et al. (2019), who analysed the observations of atmospheric microplastics deposition in a remote and pristine site in the French Pyrenees, also through numerical backward trajectories. Based on their dataset, they showed that microplastics could arrive at the site from distances up to about 100 km. Yet, they considered that it was unlikely to have only microplastic emissions from local sources, because of the low population density in the area. The results of MILORD simulations for different periods showed that for this case study the dominant scale of the microplastics transport process is regional up to mesoscale, while long-range transport may contribute when the tracer is mostly travelling in the free atmosphere before being deposited at the site. The relative contributions of dry and wet depositions and corresponding rates were also assessed. It was confirmed that plastic particles characterised by the highest settling velocities, reasonably associated to large particles, are unlikely to be subjected to long-range transport.

Convergence of mechanistic modeling and artificial intelligence in hydrologic science and engineering

Hydrology is a mature physical science based on application of first principles. However, the water system is complex and its study requires analysis of increasingly large data available from conventional and novel remote sensing and IoT sensor technologies. New data-driven approaches like Artificial Intelligence (AI) and Machine Learning (ML) are attracting much “hype” despite their apparent limitations (transparency, interpretability, ethics). Some AI/ML applications lack in addressing explicitly important hydrological questions, focusing mainly on “black-box” prediction without providing mechanistic insights. We present a typology of four main types of hydrological problems based on their dominant space and time scales, review their current tools and challenges, and identify important opportunities for AI/ML in hydrology around three main topics: data management, insights and knowledge extraction, and modelling structure. Instead of just for prediction, we propose that AI/ML can be a powerful inductive and exploratory dimension-reduction tool within the rich hydrological toolchest to support the development of new theories that address standing gaps in changing hydrological systems. AI/ML can incorporate other forms of structured and non-structured data and traditional knowledge typically not considered in process-based models. This can help us further advance process-based understanding, forecasting and management of hydrological systems, particularly at larger integrated system scales with big models. We call for reimagining the original definition of AI in hydrology to incorporate not only today’s main focus on learning, but on decision analytics and action rules, and on development of autonomous machines in a continuous cycle of learning and refinement in the context of strong ethical, legal, social, and economic constrains. For this, transdisciplinary communities of knowledge and practice will need to be forged with strong investment from the public sector and private engagement to protect water as a common good under accelerated demand and environmental change.

Scale-dependent analysis of angular momentum flux in high-resolution magnetohydrodynamic simulations for solar differential rotation

ABSTRACT In this work, we systematically investigate the scale-dependent angular momentum flux by analysing high-resolution three-dimensional magnetohydrodynamic simulations in which the solar-like differential rotation is reproduced without using any manipulations. More specifically, the magnetic angular momentum transport (AMT) plays a dominant role in the calculations. We examine the important spatial scales for the magnetic AMT. The main conclusions of our approach can be summarized as follows: 1. Turbulence transports the angular momentum radially inward. This effect is more pronounced in the highest resolution calculation. 2. The dominant scale for the magnetic AMT is the smallest spatial scale. 3. The dimensionless magnetic correlation is low in the high-resolution simulation. Thus, chaotic but strong small-scale magnetic fields achieve efficient magnetic AMT.

Elastic softening and hardening at intersections between twin walls and surfaces in ferroelastic materials

Surfaces play a key role during ferroelastic switching and define the interactions of materials with ionic species and biological systems. Here, we perform molecular dynamics simulations and identify ridges and valleys with rounded singularities around the intersections between twin walls and surfaces. Two dominant length scales stem from the elastic bending of the surface layer (>30 lattice units) and local atomic reshuffles (some five lattice units). For static twin walls, which do not shift laterally under external stress, the intrinsic change in Young’s modulus involves softening near valleys and hardening near ridges. The boundary-induced changes in the surface Young’s modulus are of the order of 0.7%.

Musicological analysis of the recitation of Surah Al-Fatiha in the musically-performed congregational worship

The Qur’anic recitation with melodious vocals and melodies has a significant role in implementing congregational prayers in a mosque. Musical recitation by a competent Imam can increase the worshipers’ comfort during the prayers. However, little is known to the general public about what is behind the beautiful recited voice. Some Muslims believe that the recitation of the Qur’an in prayer could not be included as music, even though some musicological aspects support its aesthetics. Although the artistic significance of the Qur’an’s recitation is not uncommon among Muslims and even contested openly, the musicological aspects of its recitation in congregational prayer rarely be discussed. The problem discussed in this study is what underlies the recitation of a trained Imam so that the worshippers sincerely feel comfort in following the congregational. This study aims to identify the scale modes within recited Qur’anic verses by the Imam during the congregational prayer at the Jogokariyan Mosque in Yogyakarta. This research uses qualitative methods with a participating observation as its approach. The analysis unit of this study is the Al-Fatiha Chapter recitation by one of the best Imams of the mosque while leading the congregational prayers during the month of Ramadhan this year. Data disclosure uses musicological analysis involving field data recording transcription and theoretical methods. The research stage includes the field research process, transcription from the Qur’anic reading by the subject, theoretical analysis, and formulating findings. This study has resulted in an array of knowledge concerning the Imams and Muadzin management system and the characteristics of the Qur’anic recitation performed by the research subject. From a Western musicological perspective, the music transcription showed varieties of Qur’anic recitation tunes produced by the Imam within the framework of major and minor scale modes. The Imam clarified that the recitation implemented Islamic music theory known as maqam types. In conclusion, the Bayati maqam applied by the Imam resembles the Phrygian Mode of Medieval mode. Meanwhile, the Hijaz maqam resembles the Phrygian Dominant scale. Implication: While for some circles of Islamic society, music is controversial in reality, many valued aspects of Islamic religious activities can contribute to the development of musicological studies.

Knowledge Gaps and Impact of Future Satellite Missions to Facilitate Monitoring of Changes in the Arctic Ocean

Polar-orbiting satellite observations are of fundamental importance to explore the main scientific challenges in the Arctic Ocean, as they provide information on bio-geo-physical variables with a denser spatial and temporal coverage than in-situ instruments in such a harsh and inaccessible environment. However, they are limited by the lack of coverage near the North Pole (Polar gap), the polar night, and frequent cloud cover or haze over the ocean and sea ice, which prevent the use of optical satellite instruments, as well as by the limited availability of external validation data. The satellite sensors’ coverage and repeat cycles may also have limitations in properly identifying and resolving the dominant spatial and temporal scales of atmospheric, ocean, cryosphere and land variability and their interactive processes and feedback mechanisms. In this paper, we provide a state of the art of contribution of satellite observations to the understanding of the polar environment and climate scientific challenges tackled within the Arktalas Hoavva project funded by the European Space Agency. We identify the current limitations to the wider use of polar orbiting remote sensing data, as well as the observational gaps of the existing satellite missions. A comprehensive overview of all satellite missions and applications is given provided with a primary focus on the European satellites. Finally, we assess the expected capability of the approved future satellite missions to answer today’s scientific challenges in the Arctic Ocean.

A Better Approach of Assessing Lalerality by Using Combined Foot and Eye Dominance Scale in Mentally Healthy Subjects

Abstract Objective To investigate the reliability (internal consistency) of a Combined Foot and Eye Dominance Scale in healthy subjects. Materials and methods A total of 82 mentally healthy subjects were assessed with a Combined Foot and Eye Dominance Scale. The Foot Dominance Subscale included a modified Chapman & Chapman Foot Dominance scale and a new Complex Tasks scale with four foot tests reflecting more complex tasks. The Eye Dominance Subscale included three eye tests. Scale reliability statistics (item-scale statistics, summary statistics for the items, Cronbach’s alpha), nonparametric Mann-Whitney test and Spearman’s rank correlation coefficient were used. Results Considerable differences were found in the contribution of the single items to the Combined Scale. The means of some items were 37.83 times greater than those of other items (from 0.15 to 5.61), which suggested greater phenogenetic component and consequently greater contribution of these items to the total scale mean. The mean correlation between the items of the Combined Foot and Eye Dominance Scale was strongly positive (0.39), indicating good internal consistency of the scale. Conclusions Eye and foot dominance appear to be a much subtler indicator of altered hemispheric lateralization than hand dominance. The Combined Dominance Scale provides a more adequate tool for objective measuring of leftedness, as a way to assess laterality, since this scale is to a great degree unaffected by socio-cultural impact. The scale would provide comparability of leftedness as an indirect clue of abnormal lateralization in studies of mentally healthy subjects and subjects with neurodevelopmental disorders with presumed abnormal cerebral asymmetry across cultures.

The influence of romantic dominance on attitudes toward divorce of selected college students in the Philippines

In 2022, Philippine Senator Robin Padilla filed a bill to legalize divorce in the country. The bill lists 11 grounds for the filing of divorce in court. The objective of this study was to explore the degree of acceptability of these proposed divorce grounds from the viewpoint of selected college students. Based on the bill, the Philippine Divorce Attitude Questionnaire (PDAQ), a researcher-made, 5-point Likert scale questionnaire was created. In addition, the Dominance Scale was used to determine the respondents’ attitudes toward dominating a romantic relationship. Furthermore, the study attempted to determine whether a connection exists between the respondents’ PDAQ scores and their dominance scale scores. 157 college students from a school in Cainta, Rizal, Philippines volunteered to take part in this study. The PDAQ yielded total weighted means that had verbal interpretations of agree, irrespective of sex or presence of a romantic partner. Based on the PDAQ scores, in general the respondents agree to the divorce grounds laid down by the aforementioned senate bill. With respect to dominance, the respondents’ total weighted mean for the subscale of authority found that the respondents were non-authoritative. As for the dominance subscale of disparagement, the respondents’ total weighted means found that the they were non-disparaging. However, for the dominance subscale of restrictiveness, the respondents’ total weighted means showed that they were restrictive irrespective of sex or presence of a romantic partner. Furthermore, an extremely statistically significant difference between the responses of those with and without a romantic partner with respect to Dominance Disparagement subscale scores was established. Pearson r was computed between the respondents’ PDAQ scores and their dominance subscale scores in authority, restrictiveness and disparagement. A significant moderate inverse relationship was found between the respondents’ PDAQ and Dominance Authority subscale scores. This implies that for the respondents of this study, as their Dominance Authority subscale scores increase, their PDAQ scores moderately decrease and vice versa. In addition, a significant low inverse relationship between the respondents’ PDAQ and their Dominance Disparagement subscale scores was also established. In turn, this implies that for the respondents of this study, as their Dominance Disparagement subscale scores increase, their PDAQ scores slightly decrease and vice versa.

Zonal jets in the Southern Ocean: A semi-analytical model based on scale separation

A reduced-order semi-analytic model of multiple zonal jets in the Southern Ocean is proposed based on the statistical approach and scale decomposition. By introducing two dominant scales in the vorticity equation, the model describes the large-scale and mesoscale dynamics using the explicit momentum dissipation in the horizontal and vertical directions. For validation and physical insights, the results of the reduced-order model are compared with solutions of two eddy-resolving ocean models: (i) a realistic primitive-equation HYCOM (HYbrid Coordinate Ocean Model) simulation of the Southern Ocean and (ii) an idealized quasi-geostrophic model of a shear-driven channel flow.

Psychometric evaluation of a Visual Interpersonal Analog Scale.

Interpersonal theory organizes social behavior along dominant (vs. submissive) and warm (vs. cold) dimensions. There is a growing interest in assessing these behaviors in naturalistic settings to maximize ecological validity and to study dynamic social processes. Studies that have assessed interpersonal behavior in daily life have primarily relied on behavioral checklists. Although checklists have advantages, they are discrepant with techniques used to capture constructs typically assessed alongside warmth and dominance, such as affect, which typically rely on adjective descriptors. Further, these checklists are distinct from the methodologies used at the dispositional level, such as personality inventories, which rarely rely on behavioral checklists. The present study evaluates the psychometric performance of interpersonal adjectives presented on a visual analog scale in five different samples. Validity of the Visual Interpersonal Analog scale (VIAS) approach to momentary assessment was evaluated by comparing its performance with an interpersonal behavior checklist and by examining associations among the VIAS Warmth and Dominance scales and other momentary and dispositional constructs. Results were generally consistent with an existing interpersonal behavior checklist at the within-person level but diverged somewhat at the dispositional level. Across the five samples, the VIAS generally performed as hypothesized at both the within- and between-person levels. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Compound Climate Risk: Diagnosing Clustered Regional Flooding at Inter-Annual and Longer Time Scales

The potential for extreme climate events to cluster in space and time has driven increased interest in understanding and predicting compound climate risks. Through a case study on floods in the Ohio River Basin, we demonstrated that low-frequency climate variability could drive spatial and temporal clustering of the risk of regional climate extremes. Long records of annual maximum streamflow from 24 USGS gauges were used to explore the regional spatiotemporal patterns of flooding and their associated large-scale climate modes. We found that the dominant time scales of flood risk in this basin were in the interannual (6–7 years), decadal (11–13 years), and secular bands and that different sub-regions within the Ohio River Basin responded differently to large-scale forcing. We showed that the leading modes of streamflow variability were associated with ENSO and secular trends. The low-frequency climate modes translated into epochs of increased and decreased flood risk with multiple extreme floods or the absence of extreme floods, thus informing the nature of compound climate-induced flood risk. A notable finding is that the secular trend was associated with an east-to-west shift in the flood incidence and the associated storm track. This is consistent with some expectations of climate change projections.