Global Wave Research Articles

The First Stars: Formation, Properties, and Impact

The first generation of stars, often called Population III (or Pop III), form from metal-free primordial gas at redshifts z ∼ 30 and below. They dominate the cosmic star-formation history until z ∼ 15–20, at which point the formation of metal-enriched Population II stars takes over. We review current theoretical models for the formation, properties, and impact of Pop III stars and discuss existing and future observational constraints. Key takeaways from this review include the following: ▪Primordial gas is highly susceptible to fragmentation and Pop III stars form as members of small clusters with a logarithmically flat mass function.▪Feedback from massive Pop III stars plays a central role in regulating subsequent star formation, but major uncertainties remain regarding its immediate impact.▪In extreme conditions, supermassive Pop III stars can form, reaching masses of several 105M⊙. Their remnants may be the seeds of the supermassive black holes observed in high-redshift quasars.▪Direct observations of Pop III stars in the early Universe remain extremely challenging. Indirect constraints from the global 21-cm signal or gravitational waves are more promising.▪Stellar archeological surveys allow us to constrain both the low-mass and the high-mass ends of the Pop III mass distribution. Observations suggest that most massive Pop III stars end their lives as core-collapse supernovae rather than as pair-instability supernovae.

A multidimensional interpretation analysis of Marxism globalization theory based on distributed Internet

Abstract In the environment of increasing pace of globalization and informatization, the distributed internet has effectively mobilized people from all countries to participate in the discussion of Marxist theory, which makes Marxist theory enriched in a decentralized, multi-node manner for the first time under the wave of globalization. Although the modern emerging distributed internet is faster and more rapid than the traditional information media methods, its accuracy is subject to a greater impact. In this paper, we collect the information of text-video web pages through a crawler program, and after filtering through artificial intelligence retrieval technology to obtain the Marxist globalization theory and extract key information points, and delete irrelevant information. Then K-means clustering algorithm is used to cluster the information collected in the distributed internet to obtain the multidimensional interpretation of Marxist’s globalization theory. This method has been proved to be effective through a large number of experiments. The existing distributed internet has a large amount of data that can be used to train artificial intelligence and has good practical conditions. This method helps Marxists to make better use of information from multiple nodes. The theoretical perspectives of working people from various countries are constantly gathered and pushed forward while saving a lot of manpower, so that Marxism can be better adapted to the rapidly developing globalized society.

Cross-cultural Management Problems and Countermeasures of Multinational Corporations: Take M Group's Acquisition of X Company as an Example

With the development of economic globalization, Merger and Acquisition wave is becoming more and more popular in Chinese enterprises. In recent years, driven by the policies of the Belt and Road Initiative, China's "going global" has become an inevitable trend of development. Due to the staggered cultural backgrounds of different countries and different histories and cultures, the cross-cultural management of enterprises directly affects the exertion of the overall management efficiency of enterprises. Taking M Group M&A X Company as an example, this paper analyzes the influence of M Group on the decision-making of M Group M&A X Company, and concludes that multinational enterprises, on the basis of in-depth understanding of the enterprise culture and foreign culture, must choose the appropriate cross-cultural management mode within the enterprise, so that different types of culture can achieve the best integration effect, and provide reference suggestions for Chinese enterprises to "go out."

Peran Pendidikan Pancasila dan Kewarganegaraan dalam menghadapi arus globalisasi

The increasingly rapid flow of globalization today, of course, has a major negative impact on the civic character of the Indonesian population, especially young people. Therefore, it is not surprising that the character of the Indonesian nation based on Pancasila is now starting to fade. Therefore, this research examines the role of Pancasila and Citizenship Education in facing the flow of globalization. This research uses quantitative methods obtained from literature studies and scientific data that correspond to facts, then presented in writing. The results of this literature study show that the role of Pancasila and Citizenship lessons in the rapid wave of globalization, is that it really has an impact on young people in securing and practicing the existing PPKN morals and creating young people who are still in school and then adhere to the guidelines, are moral, obedient, commitment to obeying applicable rules, sharp thinking as well as high levels of worship and creativity.

Lowermost Mantle Structure Beneath the Central Pacific Ocean: Ultralow Velocity Zones and Seismic Anisotropy

AbstractUltralow velocity zones (ULVZs) and seismic anisotropy are both commonly detected in the lowermost mantle at the edges of the two antipodal large low velocity provinces (LLVPs). The preferential occurrences of both ULVZs and anisotropy at LLVP edges are potentially connected to deep mantle dynamics; however, the two phenomena are typically investigated separately. Here we use waveforms from three deep earthquakes to jointly investigate ULVZ structure and lowermost mantle anisotropy near an edge of the Pacific LLVP to the southeast of Hawaii. We model global wave propagation through candidate lowermost mantle structures using AxiSEM3D. Two structures that cause ULVZ‐characteristic postcursors in our data are identified and are modeled as cylindrical ULVZs with radii of ∼1° and ∼3° and velocity reductions of ∼36% and ∼20%. One of these features has not been detected before. The ULVZs are located to the south of Hawaii and are part of the previously detected complex low velocity structure at the base of the mantle in our study region. The waveforms also reveal that, to first order, the base of the mantle in our study region is a broad and thin region of modestly low velocities. Measurements of Sdiff shear wave splitting reveal evidence for lowermost mantle anisotropy that is approximately co‐located with ULVZ material. Our measurements of co‐located anisotropy and ULVZ material suggest plausible geodynamic scenarios for flow in the deep mantle near the Pacific LLVP edge.

Unions, Strikes, Shaw (Unions, Strikes, Shaw: “The Capitalism of the Proletariat.”)

Unions, Strikes, Shaw (Unions, Strikes, Shaw: “The Capitalism of the Proletariat.”)

Konsep Pendidikan Islam di Era Globalisasi: Studi Pemikiran KH. Abdurrahman Wahid

This research aims to explore the concept of Islamic education in the era of globalization from the perspective of KH. Abdurrahman Wahid. The study is based on concerns about the impact of globalization, referred to as "future shock" by the renowned futurologist Alvin Toffler. The researcher observes that the education sector in Indonesia lacks a clear concept to face this wave of globalization. Therefore, this study seeks to delve into the concept of Islamic education in the era of globalization, characterized by neo-modernism, which involves preserving traditional values while incorporating Western modernization. The research adopts the Library Research method, focusing on various literature sources such as books, articles, and newspapers. Data collection employs documentary techniques. The study utilizes a historical-philosophical approach and content analysis as the analytical method. The findings reveal that the concept of Islamic education in the perspective of KH. Abdurrahman Wahid during the era of globalization consists of three core discussions. Firstly, the goals of Islamic education encompass neomodernism, liberation-based education, and multiculturalism-based education. Secondly, the Islamic education curriculum includes the formation of Islamic personality, Islamic culture development, and the advancement of life sciences, skills, and expertise. Thirdly, the methods of Islamic education involve political, cultural, and socio-cultural strategies. Additionally, the concept of Islamic education from the perspective of KH. Abdurrahman Wahid exhibits an eclectic ideology, indicating its distinctive characteristics in the realm of educational ideology. This research hopes that the concept can serve as an alternative reference for the education sector in Indonesia to confront the challenges of globalization.

Spermatozoa methylome and its sensitivity to water temperature in a teleost fish

Global climate change and heat waves are sources of stress which fish are facing in the wild as well as in aquaculture context. In coping with important environmental variations, they demonstrate a great plasticity and a tendency for acclimation throughout generations. Here, we question whether fish might be prone to transmit epigenetic alterations through their gametes to their offspring, thus driving rapid environmental adaptation. The question of epigenetic inheritance in fish has become of crucial interest in the recent years, when the mammalian model of methylome erasure in germ cells and embryos was found not to be conserved. In this work, by sequencing spermatozoa after bisulfite conversion, we characterized the methylation landscape of the paternal gamete in rainbow trout (in comparison to muscle) before to demonstrate its sensitivity to a 4 °C increased rearing temperature during spermatogenesis. We found that spermatozoa methylome specifically primes housekeeping and developmental genes for activation and might be instrumental to early development. Most of these methylation-free promoters were not affected by temperature, attesting the robustness of the epigenetic programming of early development. However, the increase of temperature triggered the differential methylation of 5359 regions, among which 560 gene promoters control spermiogenesis and lipid metabolism. We therefore report, for the first time in fish, that sperm epigenetic landscape carries marks of parental thermal living conditions, suggesting that DNA methylation might be a molecular basis of intergenerational inheritance.

Historical global ocean wave data simulated with CMIP6 anthropogenic and natural forcings

This dataset presents historical ocean wave climate during 1960–2020, simulated using the numerical model WAVEWATCH III (WW3) forced by Coupled Model Intercomparison Project phase 6 (CMIP6) simulations corresponding to natural-only (NAT), greenhouse gas-only (GHG), aerosol-only (AER) forcings, combined forcing (natural and anthropogenic; ALL), and pre-industrial control conditions. Surface wind at 3-hourly temporal resolution, and sea-ice area fraction at monthly frequency, from a CMIP6 model - MRI-ESM2.0 are used to force WW3 over the global ocean. Model calibration and validation of the significant wave height are carried out using inter-calibrated multi-mission altimeter data produced by the European Space Agency Climate Change Initiative, with additional corroboration using ERA-5 reanalysis. The simulated dataset is assessed for its skill to represent mean state, extremes, trends, seasonal cycle, time consistency, and spatial distribution over time. Numerically simulated wave parameters for different individual external forcing scenario is not available yet. This study produces a novel database particularly useful for detection and attribution analysis to quantify the relative contributions of natural and anthropogenic forcings to historical changes.

The effect of the operational environment on the survivability of passenger ships

The in-force probabilistic framework for passenger ship survivability assessment covers collision hazards. The framework primarily pertains to a static approach. Nonetheless, more complex dynamic analyses usually employ the same damage definitions, adding besides the breach characteristics, the environmental condition selection or, more precisely, the irregular wave environment necessary to simulate the damage scenarios. The traditional dynamic approaches to survivability consider only the significant wave height sampled from statistical formulations, with the wave period deriving from a constant steepness assumption. However, wave height and period influence ship dynamics in waves differently, especially concerning survivability after damage. Therefore, aiming at a direct assessment of ship survivability and the probability of loss of lives determination in realistic operational scenarios, it is essential to properly study the influence of combined variations of wave height and periods and their occurrence. The present study proposes a methodology for dynamic simulations in site-specific conditions derived from the Global Wave Statistics. The study documents the process in two critical collision damages for a reference passenger ship, using wave height and period combinations typical of the main sea areas of interest for passenger ships and performing a sensitivity analysis on the simulations needed to evaluate survivability. This enhanced analysis allows identifying the limiting environmental conditions for the critical damage cases, including the effect of heading variations, determining the ship’s survivability to specific damage in an operational area.

Effective Reconstruction of Expectation Values from Ab Initio Quantum Embedding.

Quantum embedding is an appealing route to fragment a large interacting quantum system into several smaller auxiliary "cluster" problems to exploit the locality of the correlated physics. In this work, we critically review approaches to recombine these fragmented solutions in order to compute nonlocal expectation values, including the total energy. Starting from the democratic partitioning of expectation values used in density matrix embedding theory, we motivate and develop a number of alternative approaches, numerically demonstrating their efficiency and improved accuracy as a function of increasing cluster size for both energetics and nonlocal two-body observables in molecular and solid state systems. These approaches consider the N-representability of the resulting expectation values via an implicit global wave function across the clusters, as well as the importance of including contributions to expectation values spanning multiple fragments simultaneously, thereby alleviating the fundamental locality approximation of the embedding. We clearly demonstrate the value of these introduced functionals for reliable extraction of observables and robust and systematic convergence as the cluster size increases, allowing for significantly smaller clusters to be used for a desired accuracy compared to traditional approaches in ab initio wave function quantum embedding.

Improved estimates of extreme wave conditions in coastal areas from calibrated global reanalyses

The analysis of extreme wave conditions is crucial for understanding and mitigating coastal hazards. As global wave reanalyses allow to extend the evaluation of wave conditions to periods and locations not covered by in-situ measurements, their direct use is common. However, in coastal areas, the accuracy of global reanalyses is lower, particularly for extreme waves. Here we compare two leading global wave reanalyses against 326 coastal buoys, demonstrating that both reanalyses consistently underestimate significant wave height, 50-year return period and mean wave period in most coastal locations around the world. Different calibration methods applied to improve the modelled extreme waves, resulting in a 53% reduction in the underestimation of extreme wave heights. Importantly, the 50-year return period for significant wave height is improved on average by 55%. Extreme wave statistics determined for coastal areas directly from global wave reanalyses require careful consideration, with calibration largely reducing uncertainty and improving confidence.

International Sanctions and Limits of Lerner Symmetry

After a wave of globalization, trade wars and financial sanctions again become frequent tools of international policymaking, leading to an increased interest in the consequences and effectiveness of international sanctions. Itskhoki and Mukhin (2022b) show that Lerner symmetry provides an important benchmark with import and export sanctions equivalent in terms of their effects on allocations and welfare. This abstracts from several practical issues, including the timing of sanctions, interactions between trade and financial restrictions, and the effects of sanctions on the financial sector. We incorporate these features to study their implications and emphasize points of departure from Lerner symmetry.

The Belt and Road Initiative: Inclusive Globalization and Poverty Reduction

The Belt and Road Initiative (BRI) aims to increase connectivity between regions and countries that market forces excluded from the previous wave of economic globalization. Foreign direct investment (FDI) can create the conditions for the economic takeoff of least-developed countries (LDCs) and developing countries. Although Chinese FDI has nearly doubled since the launch of the BRI in 2013 compared to 2005–2013, it does not seem to be directed toward BRI member countries more than the non-member countries. One exception is South American BRI member countries, which have significantly increased their FDI inflows from China. This is not the case, however, for West Asian countries, where FDI growth has been lower for BRI countries than for the West Asian countries as a whole, and especially for sub-Saharan BRI countries, for which the amount of FDI has even decreased compared to the 2005–2013 period. The BRI’s slow start and the countries’ gradual entry may explain the delay in seeing the positive results expected from it reflected in the data.

Effects of Emerging Bipolar Magnetic Regions in Mean-field Dynamo Model of Solar Cycles 23 and 24

We model the physical parameters of Solar Cycles 23 and 24 using a nonlinear dynamical mean-field dynamo model that includes the formation and evolution of bipolar magnetic regions (BMRs). The Parker-type dynamo model consists of a complete MHD system in the mean-field formulation: the 3D magnetic induction equation, and 2D momentum and energy equations in the anelastic approximation. The initialization of BMRs is modeled in the framework of Parker’s magnetic buoyancy instability. It defines the depths of BMR injections, which are typically located at the edge of the global dynamo waves. The distribution with longitude and latitude and the size of the initial BMR perturbations are taken from the NOAA database of active regions. The modeling results are compared with various observed characteristics of the solar cycles. Only the BMR perturbations located in the upper half of the convection zone lead to magnetic active regions on the solar surface. While the BMRs initialized in the lower part of the convection zone do not emerge on the surface, they still affect the global dynamo process. Our results show that BMRs can play a substantial role in the dynamo processes and affect the strength of the solar cycles. However, the data driven model shows that the BMR’s effect alone cannot explain the weak Cycle 24. This weak cycle and the prolonged preceding minimum of magnetic activity were probably caused by a decrease of the turbulent helicity in the bulk of the convection zone during the decaying phase of Cycle 23.

Global Dynamical Network of the Spatially Correlated Pc2 Wave Response for the 2015 St. Patrick's Day Storm

AbstractWe show the global dynamics of spatial correlation of Pc2 wave activity can track the evolution of the 2015 St. Patrick's Day geomagnetic storm for an 8 hr time window around onset. The global spatially coherent response is tracked by forming a dynamical network from 1 s data using the full set of 100+ ground‐based magnetometer stations collated by SuperMAG and Intermagnet. The pattern of spatial coherence is captured by network parameters which in turn track the evolution of the storm. At onset interplanetary magnetic field (IMF) Bz > 0 and Pc2 power increases, we find a global response with stations correlated over both local and global distances. Following onset, whilst Bz > 0, the network response is confined to the day‐side. When IMF Bz < 0, there is a strong local response at high latitudes, consistent with the onset of polar cap convection driven by day‐side reconnection. The spatially coherent response as revealed by the network grows and is maximal when auroral (SuperMAG electrojet) and ring current (SuperMAG ring current) 1 min resolution geomagnetic indices peak, consistent with an active electrojet and ring‐current. Throughout the storm there is a coherent response both in stations located along lines of constant geomagnetic longitude, between hemispheres, and across magnetic local time. The network does not simply track average Pc2 wave power, it is characterized by network parameters which track the storm evolution. This is the first study to parameterize global Pc2 wave correlation and offers the possibility of statistical studies across multiple events and comparison with, and validation of, space weather models.

The Impacts of the Application of the Ensemble Optimal Interpolation Method in Global Ocean Wave Data Assimilation

The ensemble optimal interpolation method was used in this study to conduct an examination of the assimilations of significant wave height (SWH) data from HY-2A satellite altimeter based on the WAVEWATCH III global ocean wave model. The results suggested that the ensemble optimal interpolation method using HY-2A SWH data played a positive role in enhancing the accuracy of the global ocean wave simulations and could effectively improve the deviations of SWH in the simulation processes. The root mean square errors of the NDBC buoy inspections were improved by 7 to 44% after the assimilation, and those of China’s offshore buoy inspections were improved by 3 to 11% after the assimilation. It was observed that the farther the buoys were from the shore, the better the effects of the assimilation improvements. The root mean square errors of the Jason-2 satellite data validations were improved by 17% after the assimilation, with monthly improvements of 8–25%. The improvements occurred in most of the global oceans, particularly in the Southern Ocean, the Eastern Pacific Ocean and the Indian Ocean. The results obtained in this research can be used as a reference for the operational applications of China’s ocean satellite data in ocean wave data assimilation and prediction.

State of the world 2022: defiance in the face of autocratization

ABSTRACT This article presents the state of democracy in the world in 2022 using the most recent Varieties of Democracy dataset (V13). There are four main findings. First, the level of democracy enjoyed by the average global citizen is down to 1986-levels and 72% of the world’s population live in autocracies. Second, the third wave of autocratization reaches a new height with 42 countries autocratizing. By contrast, only 14 countries are democratizing. Third, between 1992 and 2022, autocracies increased their share of the global economy and now account for 46% of world GDP when measured by purchasing power parity. Fourth, defying the global wave of autocratization, eight countries not only stopped but also reversed autocratization in the last 10 years, which we define as democratic U-turns. We find five elements that seem important across the identified cases: executive constraints, mass mobilization, alternation in power, unified opposition coalescing with civil society, and international democracy support. We analyze different combinations of these factors and discuss how they could be critical in stopping and reversing contemporary autocratization. This first analysis suggests that in-depth, comparative case studies of these eight cases and their counterfactuals would be an important area of future research.

Environmental Contours in the Adriatic Sea for Design and Analysis of Marine Structures

The environmental contours represent an approach for defining extreme environmental conditions, resulting in extreme responses of marine structures with a given return period. Over the past decade, an increasing number of studies have been developed dealing with the methods for defining environmental contours and enhancing their practical application in different marine environments. In the present study, environmental contours describing significant wave heights and peak wave periods are created for the Adriatic Sea. This small semi-enclosed sea basin within the Mediterranean Sea encounters increasing maritime and offshore activities. Considering also a great but still unused potential for the installation of renewable energy facilities, the main motives for the presented study are concluded. The environmental contours are established based on 24 years of hindcast wave data extracted from the WorldWaves database. Joint distributions consisting of the marginal distribution of significant wave height and conditional distributions of peak wave periods are used as a basis for the creation of environmental contours using the IFORM and ISORM methods. Return periods of 1 year, 25 years, and 100 years are considered relevant for the marine operation, design of ships, and offshore structures, respectively. A possibility of environmental contour practical application to the calculation of global wave loads upon ship structures is presented. Based on the uncertainty assessment performed, conservative environmental contours for the whole Adriatic are also presented.

Ensemble-based data assimilation of significant wave height from Sofar Spotters and satellite altimeters with a global operational wave model

An ensemble-based method for wave data assimilation is implemented using significant wave height observations from the globally distributed network of Sofar Spotter buoys and satellite altimeters. The Local Ensemble Transform Kalman Filter (LETKF) method generates skillful analysis fields resulting in reduced forecast errors out to 2.5 days when used as initial conditions in a cycled wave data assimilation system. The LETKF method provides more physically realistic model state updates that better reflect the underlying sea state dynamics and uncertainty compared to methods such as optimal interpolation. Skill assessment far from any included observations and inspection of specific storm events highlight the advantages of LETKF over an optimal interpolation method for data assimilation. This advancement has immediate value in improving predictions of the sea state and, more broadly, enabling future coupled data assimilation and utilization of global surface observations across domains (atmosphere-wave-ocean).