Long-wave Research Articles

Assessment of agronomic performances of aromatic varieties in stations in the senegal river valley (vfs)

Senegal is one of the largest rice importing countries in West Africa with rice production that still fails to meet consumer demands. The State has made great efforts to make up for the deficit in local production by setting up the Program for the Acceleration of the Agricultural Cadence in Senegal (PRACAS) and the National Program for Self-sufficiency in Rice (PNAR), whose objective is to satisfy national demand with a halt in imports. To support this dynamic, the Senegalese Institute for Agricultural Research (ISRA) has revised these research activities with the introduction of a major selection component for new high-yielding rice varieties with good grain quality. It is within this framework, in partnership with BAYER, that the ISRA of Saint Louis is evaluating new varieties of hybrid rice. This study attempts to evaluate the behavior of new hybrid varieties according to two sowing methods in the Senegal River Valley. The material is composed of two hybrid varieties 6444 GOLD and TEJ GOLD and a control Sahel 108. The device is in split-plot with the sowing methods in large plots and the varieties in small plots. The effect of the sowing method on the behavior of the varieties was only noted to be significant on the cycle at maturity; the hybrids have longer cycles than the control Sahel 108 both in direct sowing and in transplanting. The varieties have different agronomic behaviors only on the weight of 1000 seeds, the length of the panicle and the duration of cycles at 50% flowering. The TEJ GOLD variety has a long panicle and a good grain load per panicle. The best performances such as very good tillering ability (6444 GOLD) and good panicle load (TEJ GOLD) were recorded in the hybrids. These hybrids would behave better in direct seeding in terms of yield, unlike the control Sahel 108. From the above, we can say that the introduction of these hybrid varieties could significantly increase rice production and productivity and contribute to achieve our self-sufficiency in rice.

The Uncertainty Analysis of the Entrance Pupil Irradiance for a Moon-Based Earth Radiation Observation Instrument

Moon-Based Earth Radiation Observation (MERO) is expected to improve and enrich the current Earth radiation budget (ERB). For the design of MERO’s instrument and the interpretation of Moon-based data, evaluating the uncertainty of the instrument’s Entrance Pupil Irradiance (EPI) is an important part. In this work, by analyzing the effect of the Angular Distribution Models (ADMs), Earth’s Top of Atmosphere (TOA) flux, and the Earth–Moon distance on the EPI, the uncertainty of EPI is finally studied with the help of the theory of errors. Results show that the ADMs have a stronger influence on the Short-Wave (SW) EPI than those from the Long-Wave (LW). For the change of TOA flux, the SW EPI could keep the attribute of varying hourly time scales, but the LW EPI will lose its hourly-scale variability. The variation in EPI caused by the hourly change of the Moon–Earth distance does not exceed 0.13 mW∙m−2 (1σ). The maximum hourly combined uncertainty reveals that the SW and LW combined uncertainties are about 5.18 and 1.08 mW∙m−2 (1σ), respectively. The linear trend extraction of the EPI demonstrates that the Moon-based data can effectively capture the overall linear change trend of Earth’s SW and LW outgoing radiation, and the uncertainty does not change the linear trend of data. The variation of SW and LW EPIs in the long term are 0.16 mW∙m−2 (SW) and 0.23 mW∙m−2 (LW) per decade, respectively. Based on the constraint of the uncertainty, a simplified dynamic response model is built for the cavity radiometer, a kind of MERO instrument, and the results illuminate that the Cassegrain optical system and electrical substitution principle can realize the detection of Earth’s outing radiation with the sensitivity design goal 1 mW∙m−2.

Establishing a Gold Standard for Quantitative Menstrual Cycle Monitoring.

Background and Objectives: The Quantum Menstrual Health Monitoring Study will measure four key reproductive hormones in the urine (follicle-stimulating hormone, FSH; estrone-3-glucuronide, E13G; luteinizing hormone, LH; and pregnanediol glucuronide, PDG) to characterize patterns that predict and confirm ovulation, referenced to serum hormones and the gold standard of the ultrasound day of ovulation in participants with regular cycles. These normal cycles will provide a reference for comparison to irregular cycles in subjects with polycystic ovarian syndrome (PCOS) and athletes. Materials and Methods: Participants will track their menstrual cycles for 3 months and be provided with an at-home urine hormone monitor (Mira monitor) to predict ovulation. The day of ovulation will be confirmed with serial ultrasounds completed in a community clinic. Urine results will be compared to serum hormone values. Other markers of menstrual health, such as bleeding patterns and temperature changes, will be determined using a customized app. Three groups will be recruited. Group 1 will include those with consistent regular cycle lengths (between 24-38 days), and will be compared to two groups with irregular cycle lengths (with increased cycle length variability and longer cycles). Group 2 will include those with polycystic ovarian syndrome (PCOS) with irregular cycles and Group 3 will include individuals participating in high levels of exercise with irregular cycles. Hypothesis: The Mira monitor quantitative urine hormone pattern will accurately correlate with serum hormonal levels and will predict (with LH) and confirm (with PDG) the ultrasound day of ovulation in those with regular cycles as well as those with irregular cycles. Rationale: Once the ultrasound validation is complete, tools like the Mira monitor with a customized app may become a new standard for at-home and remote clinical monitoring of the menstrual cycle without having to use labor-intensive follicular-tracking ultrasound or follow serum hormone changes. Conclusions: Precision monitoring of the menstrual cycle is expected to impact individuals who want to increase their menstrual health literacy and guide decisions about fertility.

Inflation dynamics in the frequency domain

We use a New Keynesian Phillips Curve to study the dynamics of inflation in the frequency domain. Inflation expectations dominate medium-to-long-run cycles, energy inflation dominate short cycles and also longer cycles once expectations became anchored. While statistically significant, unemployment is not economically relevant at any frequency band.

Evaluation of Reanalysis Estimates of Precipitation, Radiation, and Temperature over Benin (West Africa)

Abstract In West Africa, climatic data issues, especially availability and quality, remain a significant constraint to the development and application of distributed hydrological modeling. As alternatives to ground-based observations, reanalysis products have received increasing attention in recent years. This study aims to evaluate three reanalysis products, namely, ERA5, Water and Global Change (WATCH) Forcing Data (WFD) ERA5 (WFDE5), and MERRA-2, from 1981 to 2019 to determine their ability to represent four hydrological climates variables over a range of space and time scales in Benin. The variables from the reanalysis products are compared with point station databased metrics Kling–Gupta efficiency (KGE), mean absolute error (MAE), correlation, and relative error in precipitation annual (REPA). The results show that ERA5 presents a better correlation for annual mean temperature (between 0.74 and 0.90) than do WFDE5 (0.63–0.78) and MERRA-2 (0.25–0.65). Both ERA5 and WFDE5 are able to reproduce the observed upward trend of temperature (0.2°C decade−1) in the region. We noted a systematic cold bias of ∼1.3°C in all reanalyses except WFDE5 (∼0.1°C). On the monthly time scale, the temperature of the region is better reproduced by ERA5 and WFDE5 (KGE ≥ 0.80) than by MERRA-2 (KGE < 0.5). At all time scales, WFDE5 produces the best MAE scores for longwave (LW) and shortwave (SW) radiation, followed by ERA5. WFDE5 also provides the best estimates for the annual precipitation (REPA ∈ ]−25, 25[ and KGE ≥ 50% at most stations). ERA5 produces similar results, but MERRA-2 performs poorly in all the metrics. In addition, ERA5 and WFDE5 reproduce the bimodal rainfall regime in southern Benin, unlike MERRA-2, but all products have too many small rainfall events.

A Model for Estimating the Earth’s Outgoing Radiative Flux from A Moon-Based Radiometer

A Moon-based radiometer can provide continuous measurements for the Earth’s full-disk broadband irradiance, which is useful for studying the Earth’s Radiation Budget (ERB) at the height of the Top of the Atmosphere (TOA). The ERB describes how the Earth obtains solar energy and emits energy to space through the outgoing broadband Short-Wave (SW) and emitted thermal Long-Wave (LW) radiation. In this work, a model for estimating the Earth’s outgoing radiative flux from the measurements of a Moon-based radiometer is established. Using the model, the full-disk LW and SW outgoing radiative flux are gained by converting the unfiltered entrance pupil irradiances (EPIs) with the help of the anisotropic characteristics of the radiances. Based on the radiative transfer equation, the unfiltered EPI time series is used to validate the established model. By comparing the simulations for a Moon-based radiometer with the satellite-based data from the National Institute of Standards and Technology Advanced Radiometer (NISTAR) and the Clouds and the Earth’s Radiant Energy System (CERES) datasets, the simulations show that the daytime SW fluxes from the Moon-based measurements are expected to vary between 194 and 205 Wm−2; these simulations agree well with the CERES data. The simulations are about 5 to 20 Wm−2 smaller than the NISTAR data. For the simulated Moon-based LW fluxes, the range is 251~287 Wm−2. The Moon-based and NISTAR fluxes are consistently 5~15 Wm−2 greater than CERES LW fluxes, and both of them also show larger diurnal variations compared with the CERES fluxes. The correlation coefficients of SW fluxes for Moon-based data and NISTAR data are 0.97, 0.63, and 0.53 for the months of July, August, and September, respectively. Compared with the SW flux, the correlation of LW fluxes is more stable for the same period and the correlation coefficients are 0.87, 0.69, and 0.61 for July to September 2017.

Exercise-induced myocardial T1 increase and right ventricular dysfunction in recreational cyclists: a CMR study

PurposeAlthough cardiac troponin I (cTnI) increase following strenuous exercise has been observed, the development of exercise-induced myocardial edema remains unclear. Cardiac magnetic resonance (CMR) native T1/T2 mapping is sensitive to the pathological increase of myocardial water content. Therefore, we evaluated exercise-induced acute myocardial changes in recreational cyclists by incorporating biomarkers, echocardiography and CMR.MethodsNineteen male recreational participants (age: 48 ± 5 years) cycled the ‘L’étape du tour de France” (EDT) 2021’ (175 km, 3600 altimeters). One week before the race, a maximal graded cycling test was conducted to determine individual heart rate (HR) training zones. One day before and 3–6 h post-exercise 3 T CMR and echocardiography were performed to assess myocardial native T1/T2 relaxation times and cardiac function, and blood samples were collected. All participants were asked to cycle 2 h around their anaerobic gas exchange threshold (HR zone 4).ResultsEighteen participants completed the EDT stage in 537 ± 58 min, including 154 ± 61 min of cycling time in HR zone 4. Post-race right ventricular (RV) dysfunction with reduced strain and increased volumes (p < 0.05) and borderline significant left ventricular global longitudinal strain reduction (p = 0.05) were observed. Post-exercise cTnI (0.75 ± 5.1 ng/l to 69.9 ± 41.6 ng/l; p < 0.001) and T1 relaxation times (1133 ± 48 ms to 1182 ± 46 ms, p < 0.001) increased significantly with no significant change in T2 (p = 0.474). cTnI release correlated with increase in T1 relaxation time (p = 0.002; r = 0.703), post-race RV dysfunction (p < 0.05; r = 0.562) and longer cycling in HR zone 4 (p < 0.05; r = 0.607).ConclusionStrenuous exercise causes early post-race cTnI increase, increased T1 relaxation time and RV dysfunction in recreational cyclists, which showed interdependent correlation. The long-term clinical significance of these changes needs further investigation.Trial registration numbers and dateNCT 04940650 06/18/2021. NCT 05138003 06/18/2021.

Инновационный процесс в Арктике: мировые тенденции и актуальные российские проблемы

The pursuit of innovation-driven growth in the Russian Arctic aligns with global trends associated with the advent of a new Kondratieff cycle, which spurs demand for groundbreaking technologies. This article aims to identify significant trends and challenges related to innovation in the Arctic that require focused attention and further research. The concept of national and regional innovation systems serves as the theoretical framework, with a selective comparative study of Russian and international practices as the primary research method. Our analysis demonstrates that Russia lags behind the majority of Arctic nations in terms of innovation ratings, including the quality of institutions, the structure of the economy, and infrastructure development. Research and industrial policy priorities remain unclear. Innovations enter the Russian Arctic through large-scale projects within extractive industries, which rely on imported technologies and raw material exports. However, as Norway’s experience proves, these projects can leverage the research and production potential of the North if government support is provided. The article addresses corporate challenges associated with digitalization in the Arctic using fiber cable installation as a case study. Currently, the only operational lines are the line located off the Alaska North Slope and the first leg of the Russian Polar Express line, which provides Russia with an important competitive edge. We conclude that the government should play a crucial role in promoting innovations in the Russian Arctic, acting through state-owned enterprises, public agencies, and subsidized private entities. The novelty of the study lies in addressing phenomena that have received insufficient attention in Russian research while considering international practices. The practical relevance of the study lies in its potential application to strategic planning for innovation-driven growth in the Arctic. Further research should seek to identify and closely study specific challenges of the Russian Arctic innovation system in comparison with international best practices in order to provide concrete practical recommendations.

Hydrological modeling with physics-based models in the oueme basin: Issues and perspectives for simulation optimization

Study regionOueme Basin, threatened by climate change and upstream energy projects, is limited by the quality of the adapted meteorological data through the assessment of their impacts with some models. Study focusThis study focuses on the ParFlow-CLM model and describes its ability to simulate the water balances with good (observation data) and bad (observation transformed and reanalysis corrected and uncorrected data) meteorological forcing. New hydrological insights for the regionThe model correctly simulates all the terms of water balance, mainly evaporation and water table depth (WTD) with KGE always higher than 0.70. It is less sensitive to temperature, shortwave (SW), and longwave (LW) forcing. With those three variables, ParFlow-CLM simulates none significative difference in water balance terms using the reanalysis forcings on which we note an overestimation of temperature and an underestimation of LW. The same results are obtained with the other so-called bad meteorological forcings. On the other hand, the precipitation of the latter significantly influences the water balance. The annual water balance and especially evapotranspiration shows 683 ± 70 mm for observations versus 753 ± 63 mm and 662 ± 44 mm for ERA5 and MERRA2 respectively. The corrections applied on these variables seem to work better on MERRA2 (734 mm or 51 mm difference with observations) compared to ERA5 (760 mm or 77 mm difference with observations). The temperate, SW, LW variables of the reanalyses can be used for hydrological simulations with ParFlow-CLM and probably with other physics-based models over the Beninese basins but the precipitation of these must be corrected before use.

Forcing, Cloud Feedbacks, Cloud Masking, and Internal Variability in the Cloud Radiative Effect Satellite Record

Abstract Satellite observations show a near-zero trend in the top-of-atmosphere global-mean net cloud radiative effect (CRE), suggesting that clouds did not further cool nor heat the planet over the last two decades. The causes of this observed trend are unknown and can range from effective radiative forcing (ERF) to cloud feedbacks, cloud masking, and internal variability. We find that the near-zero NetCRE trend is a result of a significant negative trend in the longwave (LW) CRE and a significant positive trend in the shortwave (SW) CRE, cooling and heating the climate system, respectively. We find that it is exceptionally unlikely (&lt;1% probability) that internal variability can explain the observed LW and SW CRE trends. Instead, the majority of the observed LWCRE trend arises from cloud masking wherein increases in greenhouse gases reduce OLR in all-sky conditions less than in clear-sky conditions. In SWCRE, rapid cloud adjustments to greenhouse gases, aerosols, and natural forcing agents (ERF) explain a majority of the observed trend. Over the northeast Pacific, we show that ERF, hitherto an ignored factor, contributes as much as cloud feedbacks to the observed SWCRE trend. Large contributions from ERF and cloud masking to the global-mean LW and SW CRE trends are supplemented by negative LW and positive SW cloud feedback trends, which are detectable at 80%–95% confidence depending on the observational uncertainty assumed. The large global-mean LW and SW cloud feedbacks cancel, leaving a small net cloud feedback that is unconstrained in sign, implying that clouds could amplify or dampen global warming.

A Comprehensive Evaluation of Three Global Surface Longwave Radiation Products

Surface longwave radiation is sensitive to climate change on Earth. This study first comprehensively evaluates the accuracies of surface longwave upward radiation (SLUR) and surface longwave downward radiation (SLDR) among the mainstream surface longwave (LW) radiation products (GLASS, CERES SYN and ERA5); then, the global annual mean values of surface LW radiation as well as its temporal variations from 2003 to 2020 are quantified. The ERA5 SLUR and SLDR show the best accuracies by direct validation, with biases/Stds/RMSEs of −1.05/18.34/18.37 W/m2 and −9.41/24.15/25.92 W/m2, respectively. The GLASS SLUR has the best accuracy under clear-sky conditions with a bias/Std/RMSE of −6.73/14.21/15.72 W/m2. The accuracy of the GLASS SLDR is comparable to CERES SYN. The merit of the GLASS LW radiation is that it can provide rich spatial details due to its high spatial resolution. The global annual mean SLUR is 399.77/398.92/398.19 W/m2, and that of the SLDR is 342.64/347.98/340.47 W/m2 for GLASS, CERES SYN and ERA5, respectively. The interannual variation trends for the three products produce substantially growing long-term trends for the global mean SLUR and SDLR over the globe and land, while there are almost no trends over the ocean. The long-term trends of the seasonal mean SLUR and SDLR in the Northern and Southern Hemispheres are asymmetrical. Our comprehensive evaluation and trend analysis of the mainstream surface LW radiation products can aid in understanding the global energy balance and climate change.

Comparison of Clouds and Cloud Feedback between AMIP5 and AMIP6

We examine the changes in clouds and cloud feedback between Phase 5 (AMIP5) and Phase 6 (AMIP6) of the Atmospheric Model Intercomparison Project. Each model is perturbed by uniformly increasing the sea surface temperature by 4 K. The simulated cloud fraction, the perturbed states and cloud radiative kernels are used to derive cloud feedback in the shortwave (SW), longwave (LW) and their sum (Net). Compared to AMIP5, the cloud fraction in AMIP6 increases by 9.1%, while the perturbation leads to a 0.25% decrease. The Net cloud feedback at the top of the atmosphere (TOA) is almost double (174%). Statistical tests support that this change is mainly due to an increase in the surface SW cloud feedback caused by optically thick, middle and low clouds. The contribution of the atmospheric Net component (12%) stems from the increase in the atmospheric LW cloud feedback, likely to play a role in weakening (strengthening) the northward (southward) meridional atmospheric energy transport, while the opposite is true for the surface LW and Net cloud feedback in the meridional oceanic energy transport. The substantial increase in cloud feedback at the TOA primarily contributes to the higher climate sensitivity. The cloud feedback spread in AMIP6 is comparable to that in AMIP5.

Direct Radiative Effects of Aerosols on Numerical Weather Forecasts—A Comparison of Two Aerosol Datasets in the NCEP GFS

Abstract This study compares aerosol direct radiative effects on numerical weather forecasts made by the NCEP Global Forecast System (GFS) with two different aerosol datasets, the Optical Properties of Aerosols and Clouds (OPAC) and MERRA-2 aerosol climatologies. The underestimation of aerosol optical depth (AOD) by OPAC over northwest Africa, central to East Africa, the Arabian Peninsula, Southeast Asia, and the Indo-Gangetic Plain, and overestimation in the storm-track regions in both hemispheres are reduced by MERRA-2. Surface downward shortwave (SW) and longwave (LW) fluxes and the top-of-the-atmosphere SW and outgoing LW fluxes from model forecasts are compared with CERES satellite observations. Forecasts made with OPAC aerosols have large radiative flux biases, especially in northwest Africa and the storm-track regions. These biases are also reduced in the forecasts made with MERRA-2 aerosols. The improvements from MERRA-2 are most noticeable in the surface downward SW fluxes. GFS medium-range weather forecasts made with the MERRA-2 aerosols demonstrated slightly improved forecast accuracy of sea level pressure and precipitation over the Indian and East Asian summer monsoon region. A stronger Africa easterly jet is produced, associated with a low pressure over the east Atlantic Ocean and west of northwest Africa. Impacts on large-scale skill scores such as 500-hPa geopotential height anomaly correlation are generally positive in the Northern Hemisphere and the Pacific and North American regions in both the winter and summer seasons.

π‐Conjugated Carbon‐Based Materials for Infrared Thermal Imaging

AbstractInfrared (IR) thermal imaging is receiving a great deal of attention due to its wide range of applications. Given multiple issues (like cost and availability) with the inorganic materials currently exploited for IR imaging, there is nowadays a great push of developing organic imaging materials. Carbon‐based materials are known to have significant transparency in the visible and IR regions and some are used as transparent conductors. Here, whether π‐conjugated carbon‐based materials are suitable for long‐wave (LW) and mid‐wave (MW) IR imaging applications is computationally assessed. Using density functional theory calculations, the IR‐vibrational properties of molecules from acenes to coronenes and fullerenes, and of periodic systems like graphene and carbon nanotubes are characterized. Fullerenes, graphenes, and double‐walled carbon nanotubes are found to be very attractive as they are transparent in both the LWIR and MWIR regions, a feature resulting from the absence of hydrogen atoms. Also, it is found that replacing hydrogen atoms in a molecule with deuterium or sulfur atoms can be an efficient way to improve their LWIR or MWIR transparency, respectively. For fused‐ring systems having hydrogen atoms on the periphery, designing molecules with trio CH‐units is another way to enhance the transparency in the LWIR region.

Experience and Prospects of Interaction between Russia and the Modern World System

The article considers the problem of Russia’s positioning in the Western-centric world-system. The views of domestic and foreign researchers have been analyzed. It is shown that the constants for Russia are the position of the semi-periphery within the framework of the capitalist world-economy, the features of a land and transcontinental power, as well as an empire, which is characterized by integration imperatives that determine territorial expansion, taking into account the alternation of periods of integration and disintegration, which interact in various proportions with the processes of modernization. The external and internal political results of the cycles of Russian modernization in the context of correlation with the influence of the capitalist world-economy have been characterized. It is substantiated that modernization in Russia led to the most positive consequences when the state was least dependent on the Western-centric capitalist world-economy and strove for autarky and transformations based on the mobilization of internal resources (a conservative model of modernization), which contributed to the achievement of true sovereignty, raising the level of economic development, domestic political centralization and successful integration policy. Relevant recommendations and scenarios for the development of the situation in terms of the correlation of the waves of the Kondratiev cycles with the periods of reforms/counter-reforms in Russia, as well as the cycles of evolution of the world political and economic system with the peculiarities of the Russian political system and foreign policy have been presented. In this regard, two main scenarios for the prospects for interaction between Russia and the capitalist world-economy have been identified. The first scenario is based on the analysis of the correlation of Kondratiev cycles with periods of reforms/counter-reforms in Russia, and the second one is guided by the logic of complete cycles of evolution of the world political and economic system, which seems to be more reasonable.

The coupled modified Yajima–Oikawa system: Model derivation and soliton solutions

In this paper, we consider a coupled modified Yajima–Oikawa (YO) system which describes the nonlinear resonant interaction between one long wave (LW) and two short waves (SWs). It is shown that this coupled system can be derived from a three-component modified nonlinear Schrödinger equations through asymptotic reductions. Furthermore, the bright, dark multi-soliton and multi-breather solutions in terms of determinants are obtained respectively by virtue of the bilinear Kadomtsev–Petviashvili-hierarchy reduction technique. The detailed analysis of dynamical properties for one- and two-solitons and breathers is performed, which show the interesting collision properties for the bright and dark solitons. Particularly, differing from the modified YO system with the single SW component, two bright solitons can undergo inelastic collisions and two dark solitons can generate the bound state in the coupled modified YO system. Finally, general bright, dark multi-soliton and multi-breather solutions are presented for the multi-component modified YO system with multi short waves.

Direct Comparison Between a Non‐Orographic Gravity Wave Drag Scheme and Constant Level Balloons

AbstractThe parameterization scheme that represents gravity waves due to convection in LMDz‐6A, the atmospheric components of the IPSL coupled climate model (IPSLCM6), is directly compared to Strateole‐2 balloon observations made in the lower tropical stratosphere from November 2019 to February 2020. The input meteorological fields necessary to run the parameterization offline are extracted from the ERA5 reanalysis and correspond to the instantaneous meteorological conditions found underneath the balloons. In general, we find a fair agreement between measurements of the momentum fluxes due to waves with periods less than 1 hr and the parameterization. The correlation of the daily values between the observations and the results of the parameterization is around 0.4, which is statistically elevated considering that we analyze around 600 days of data and surprisingly good considering that the parameterization has not been tuned: the scheme is just the standard one that helps producing a quasi‐biennial oscillation (QBO) in the IPSLCM6 model. Online simulations also show that the measured values of momentum fluxes are well representative of the zonally and averaged values of momentum fluxes needed in LMDz‐6A to simulate a QBO. The observations also show that longer waves with periods smaller than a day carry about twice as much flux as waves with periods smaller than an hour, which is a challenge since the low period waves that make the difference are potentially in the “gray zone” of most climate models.

An experimental study of a rectangular floating breakwater with vertical plates as wave-dissipating components

Floating breakwaters have received growing attention in recent years from academic and engineering sectors alike. The wave-dissipating components are commonly attached to the bottom of floating breakwaters for better wave protection performance. Vertical plates, which have been proven effective in dissipating waves, were attached to a rectangular floating breakwater in this study. A series of experiments were conducted under regular wave conditions to analyze the wave protection and motion response performances, and the effects of mounting position, mounting rows, plate porosity, and protruding plate height were examined. Our experimental results elucidated that the pitch motion plays a critical role in dissipating energy. Although variation in the settings, such as mounting with more than one row of plates, smaller plate porosity and longer protruding plate height do not cause significant changes in the mass and moment of inertia of floating breakwater, they all exert stronger confining effects on the water body beneath. The water body confined by plates significantly changes the dynamic characteristics of floating breakwaters, and increase the natural period of pitch motion towards longer waves. As a result, the violent energy dissipation and corresponding better wave protection occur at longer waves. It has been demonstrated that the primary working function of vertical plates as wave-dissipating components is due to water body confinement. This finding can be utilized to tailor the design of the vertical plates as wave-dissipating components in accordance with the seasonal weather and sea conditions at specific engineering sites.

The development of Kondratieff’s theory of long waves: the place of the AI economy humanization in the ‘competencies-innovations-markets’ model

The motivation to conduct this study is related to the uncertainty of the impact of the AI economy on the economic cycle and the need to unlock the potential of Industry 4.0 in stabilizing the global economic system amid a series of crises. The article discusses the fundamental issues of the emergence of a new theory related to the evolution of Kondratieff waves in the context of modern drivers of long-term economic development (MANBRIC technologies), taking into account the acceleration of the development of innovations and competencies. The spiraling dynamics of the co-development of competencies and the expansion of new markets are shown, which makes it possible to transform the decline phase of the Kondratieff wave into a similar linear process of maintaining economic growth rates close to the existing ones. As a result, based on the authors’ model “competencies-innovations-markets”, it is proved that subject to humanization, the AI economy allows the reduction of the cyclical nature of the world economic system. The main idea of the article is to smooth out Kondratieff’s long waves due to the humanization of the AI economy.

Global Kondratiev waves and political transformations in Russia since 1800: a relative deprivation approach

Throughout Russian history, bouts of political reform have been repeatedly succeeded by reactionary periods of counter-reform. We surmise that this historical alternation of reform and counter-reform has been driven at least in part by comparisons made by Russians between their own situation and that of their counterparts in the west. Such "relative deprivation" understandings of political change are nothing new, but we tie the history of impetus for reform in Russia explicitly to fluctuations in economic performance in the capitalist west, as represented by Kondratiev waves (K-waves) of expansion and stagnation. We posit that periods of expansion in the west have prompted periods of political reform in Russia, while periods of stagnation in the west have enabled periods of counter-reform in Russia. Although a direct causal link cannot be drawn, the timing of periods of reform and counter-reform in Russia seems to be consistent with a relative deprivation interpretation.