Vertical Speed Research Articles

Coordination schemes for resource reallocation and patient transfer in hospital alliance models

AbstractIn many countries, healthcare systems encounter the issue of imbalance between supply and demand in a hierarchical structure. The comprehensive hospitals, which possess more high‐quality resources, are often overwhelmed, while their counterparts, community hospitals, are often idle. To address this imbalance issue, certain payment schemes are generally considered effective in motivating comprehensive hospitals to divert patients downstream via resource transfer. In addition to two particular payment schemes, namely, patient payment (PP) and fee‐for‐capacity (FFC), this study also considers two hospital alliance models, the government‐led (GL‐type) and the hospital‐forged (HF‐type) alliance, for effectively overcoming the imbalance issue. Compared to the HF‐type alliance, in which each community hospital determines the price paid to the comprehensive hospital for transferring resources, the GL‐type alliance requires the payment price to be set by the regulator. Methodologically, this study devises a three‐stage sequential game to characterize the dynamics among the various entities, such as the regulator, the comprehensive hospital, the community hospitals, and the patients. Equilibrium results, in terms of the capacity sinking rate and patient transfer rate, are derived, and scheme and alliance performances are evaluated using various measurements, such as patient utility, and hospital and social welfare. We find that a direct payment scheme (FFC) under a centralized alliance model (GL‐type alliance) is more effective for both making decisions (about the patient transfer rate, capacity sinking rate, and payment price) and the performances (of each hospital's welfare, patient welfare, the waiting time per patient, and social welfare). Furthermore, our study examines the impacts of the alliance scale and finds that social welfare is first decreasing and then increasing with alliance scale. Therefore, it is suggested to establish either a one‐to‐one hospital alliance (consisting of a comprehensive and a community hospital) or a large‐scale (e.g., a comprehensive and 10 community hospitals) hospital alliance.

Mechanical strength changes of combustible municipal solid waste components during their early pyrolysis stage and mechanism analysis.

Implementation of municipal solid waste (MSW) source segregation leads to a more convenient recycle of combustible MSW components. Textiles, plastics and papers are commonly available combustible components in MSW. Their shredding is conducive to resources recovery. But these components usually have high tensile strengths and are difficult to shred. To understand their mechanical strength changes in their early pyrolysis stage will help to address this problem. In this study, a universal electronic testing machine was used to determine the breaking strengths of the materials including cotton towel, polyethylene glycol terephthalate (PET), ivory board (IB), kraft paper (KP) and wool scarf in the temperature range of 30-250°C under N2 atmosphere, and the mechanisms of their strength changes were explored. The reaction force field molecular dynamics (ReaxFF-MD) simulation was used to explain the decomposition behaviours of different sugar groups of hemicellulose in cotton and paper and the change of van der Waals energy of wool during their early pyrolysis stages. The results showed that breaking strengths of all the combustible MSW components reduced as the temperature increased. The breaking strength of PET was found to have the highest descent rate with increasing temperature, then the descent rates of wool and cotton came as the second and third, respectively. Compared with cotton, the breaking strengths of KP and IB decreased more slowly. As the temperature increased, the breaking strength of cotton reduced mainly due to the decomposition of the glucuronic acid in hemicellulose, and the reduction was characterized by CO2 release. The breaking strength reduction of PET was caused by its molecular chain being relaxed. The breaking strength reduction of wool was firstly caused by the decrease in the van der Waals energy between its molecules, and then caused by molecular chain breaking. In addition, in order to understand the influence of material size on the breaking strength change during thermal treatment, the breaking strengths of cotton yarn bundles were correlated with their yarn number and temperature. This study lays the foundation for understanding changes in mechanical strengths of combustible MSW components during their early pyrolysis stage.

Spatial infiltration and redistribution of light crude oil in heterogeneous water-bearing soil layers under different hydrogeological processes.

Two physical models were used to simulate the infiltration and redistribution process of light crude oil after leakage in a heterogeneous soil layer following water level variation and rainfall. Migration fronts and redistribution characteristics of oil during gravity seepage, water level variation, and rainfall were obtained using charge-coupled device (CCD) camera shooting and cyan-magenta-yellow‒black (CMYK)-based gray analysis, which were employed efficiently and at a low cost. Then, the influencing factors and migration mechanisms were examined. Finally, the soil water and oil contents were measured to verify the simulation results. The results are as follows: (1) the geologic lens and fine-coarse interface can intercept oil, resulting in a local highly contaminated area. (2) The crude oil infiltration path and velocity varied greatly with the different soil types and initial water contents. Within a certain range, the higher the initial water content is, the higher the lateral and vertical infiltration speeds. (3) The oil redistribution process was dominated by vertical infiltration under the condition of water level variation or rainfall, but oil-water displacement and the capillary pressure caused some oil to move horizontally near the geologic lens and fine-coarse interface. (4) Water level variation resulted in a synchronous rise or fall of the oil accumulation area, but rainfall caused it to move up. (5) Water level variation and rainfall imposed a certain influence on the periodic accumulation and release of crude oil in heterogeneous soil, especially in the presence of geologic lenses and lithologic interfaces.

Pengaruh kemiringan pada bagian sayap terhadap kelajuan tenggelam tali pemberat alat tangkap pukat cincin

Purse seine is a tool (gear) used to catch pelagic fish that form a swarm. As with other fishing gear, a purse seine unit consists of a net, a boat, and auxiliary equipment (rollers, lights, echosounders, and so on). Purse seine is a fishing gear classified in the surrounding net group. Purse seine is also known as a ring trawl because it is equipped with a ring that is used as a place to attach the coloring rope which is very important during the operation of the net. Because the net that was originally bagless will form a pocket at the end of the capture operation. The ring trawl itself has a different name in each region in Indonesia, in North Sulawesi it is known as soma pajeko. There are three technical factors that need to be considered for the success of ring trawl fishing, namely: (1) circular speed, (2) speed and depth of sinking ballast rope, and (3) speed of pulling the choir ropeThe speed of sinking is largely determined by the ballast, the type of material, the size of the thread and the size of the net bit, as well as the ratio of the length of the float rope and the ballast rope. The sinking speed of the ballast rope is calculated based on the relationship between the depth and the sinking time of the ballast rope needed. The speed of the ballast can be increased by increasing the weight of the ballast, but it must be considered because it will increase the tension of the net. Ballast weight per meter ballast ropeBut it should be considered because it will add tension to the net. Greater ballast weight per meter ballast rope will add greater sinking speed. The method used in this study is an experimental method, which is a study that looks for the influence of certain variables on other variables under tightly controlled conditions. The analysis in this study consisted of 4 net models with different slope percentages, namely 57%, 75%, 100% and 125% slopes. The results of the analysis showed that the more tilted the wing with a slope of 57%, 75% and 100%, the more the sinking rate of the ballast rope but for a slope of 125% it does not contribute to the speed of sinking 57% slope at a depth of 5.5 meters the required time is 16.37 seconds, 75% slope at a depth of 5.5 meters is 15.16 seconds, 100% slope at a depth of 5.5 meters the time required is 19.84 seconds and 125% slope the time required at a depth of 5.5 meters is 19.88 seconds. The best sinking speed of the four net models that have been made based on existing data is at 75% slope.

Evaluation of Multi-Source Precipitation Products in the Hinterland of the Tibetan Plateau

High-resolution precipitation products have been crucial for hydrology, meteorology, and environmental ecosystems over the Tibetan Plateau (TP). However, these products are usually subject to systematic errors, which may vary with time and topographic conditions. The study evaluated the suitability of four satellite-derived products (GPM IMERG, GSMaP, CMORPH, and PERSIANN-CDR) and four fusion precipitation products (ERA5-Land, CHIRPS, CMFD, and TPHiPr) by comparing with 22 rain gauges at a daily scale from 1 January 2014 to 31 December 2018 over the hinterland of the TP. The main findings are as follows: (1) TPHiPr and CMFD are better than the satellite-derived products, while the performance of CHIRPS is worse; (2) among the satellite-derived products, the quality of GPM IMERG is the highest on different time scales, and PERSIANN-CDR is better in the months of June to October, while GSMaP and CMORPH have poor performance; (3) the eight precipitation products have weaker detection capability for heavy precipitation events, and the quality of each product decreases with the increase in the precipitation threshold, while the rate of descent of fusion precipitation products is slower than that of satellite-derived products. This study demonstrates the performance of eight precipitation products over the hinterland of the TP, which is expected to provide valuable information for hydrometeorology applications.

The role of marine fish-produced carbonates in the oceanic carbon cycle is determined by size, specific gravity, and dissolution rate

Rising CO2 emissions have heightened the necessity for increased understanding of Earth's carbon cycle to predict future climates. The involvement of marine planktonic species in the global carbon cycle has been extensively studied, but contributions by marine fish remain poorly characterized. Marine teleost fishes produce carbonate minerals (‘ichthyocarbonates’) within the lumen of their intestines which are excreted at significant rates on a global scale. However, we have limited understanding of the fate of excreted ichthyocarbonate. We analyzed ichthyocarbonate produced by three different marine teleosts for mol%MgCO3 content, size, specific gravity, and dissolution rate to gain a better understanding of ichthyocarbonate fate. Based on the species examined here, we report that 75 % of ichthyocarbonates are ≤0.91 mm in diameter. Analyses indicate high Mg2+ content across species (22.3 to 32.3 % mol%MgCO3), consistent with previous findings. Furthermore, ichthyocarbonate specific gravity ranged from 1.23 to 1.33 g/cm3, and ichthyocarbonate dissolution rates varied among species as a function of aragonite saturation state. Ichthyocarbonate sinking rates and dissolution depth were estimated for the Atlantic, Pacific, and Indian ocean basins for the three species examined. In the North Atlantic, for example, ~33 % of examined ichthyocarbonates are expected to reach depths exceeding 200 m prior to complete dissolution. The remaining ~66 % of ichthyocarbonate is estimated to dissolve and contribute to shallow water alkalinity budgets. Considering fish biomass and ichthyocarbonate production rates, our results support that marine fishes are critical to the global carbon cycle, contributing to oceanic alkalinity budgets and thereby influencing the ability of the oceans to neutralize atmospheric CO2.

The Effects of Parameter Settings on Triggering Time and Climb Rate during Lean-Premixed Combustion Thermoacoustic Oscillations

This study theoretically explored the effects of parameter settings on thermoacoustic oscillations with a low-order model. Three factors were explored—combustor length, inlet gas temperature and thermal power. The research findings indicate that optimizing the parameter settings can yield better thermoacoustic oscillation suppression results. The sound pressure amplitude decreased from 3.2 × 105 Pa to 2.1 × 105 Pa as the combustor length increased from 1.2 m to 6.0 m. The triggering time increased from 0.32 s to 0.91 s when the combustion chamber length increased. The climb rate declined from 23.38 × 105 Pa/s to 3.75 × 105 Pa/s when the combustor length was elongated. The sound pressure amplitude decreased from 3.44 × 105 Pa to 2.4 × 105 Pa as the gas temperature rose from 0 to 100 °C. The triggering time and climb rate variation tendency were similar when the gas temperature increased—both declined as the gas temperature rose. The sound pressure amplitude experienced a slight fluctuation when the thermal power rose. However, the triggering time decreased from 0.26 s to 0.043 s when the thermal power improved. The climb rate increased from 18.72 × 105 Pa/s to 27.65 × 105 Pa/s when the thermal power rose. The oscillation frequency presented was completely different in three cases that had different wavelengths and oscillation intensities. The triggering time and climb rate fluctuated extensively in varying conditions, and the above two factors were interrelated and contradictory to each other when thermoacoustic oscillation was excited. This study explored parameters’ effects on triggering time and climb rate, thereby providing references for constructing a model-based control system for thermoacoustic oscillation feedback control.

Climatology of Synoptic Non-Gaussian Meteorological Anomalies in the Northern Hemisphere during 1979–2018

The analysis of spatial and temporal variability in the number of non-Gaussian extreme anomalies of climatic parameters was carried out for both the initial time series and synoptic variability in the troposphere of the Northern Hemisphere over the period 1979–2018, based on ERA-Interim reanalysis data. There are predominantly three types of empirical distribution densities at 850 hPa, each characterizing the processes of advective and convective heat transfer. At the beginning of the 21st century, compared to the end of the 20th century, there was an increase in the number of anomalies in vertical wind speed and specific humidity for the Northern Hemisphere. Additionally, there is an increase in the number of zonal wind speed anomalies in the low and middle latitudes. Regions with the maximum number of anomalies are primarily located over the continents, while for vertical wind speed anomalies, they are predominantly over the oceans. The application of R/S analysis and multifractal analysis has established that the identified tendencies (which are persistent processes) will continue in the identified regions. The time series of non-Gaussian anomalies (both initial and synoptic scales) exhibit a long-term memory of approximately four years, and synoptic extreme anomalies were found to be more predictable.

Snowfall deposition in mountainous terrain: a statistical downscaling scheme from high-resolution model data on simulated topographies

One of the primary causes of non-uniform snowfall deposition on the ground in mountainous regions is the preferential deposition of snow, which results from the interaction of near-surface winds with topography and snow particles. However, producing high-resolution snowfall deposition patterns can be computationally expensive due to the need to run full atmospheric models. To address this, we developed two statistical downscaling schemes that can efficiently downscale near-surface, low-resolution snowfall data to fine-scale snow deposition accounting for the effect of preferential deposition in mountainous regions. Our approach relies on a comprehensive, model database generated using 3D wind fields from an atmospheric model and a preferential deposition model on several thousand simulated topographies covering a broad range in terrain characteristics. Both snowfall downscaling schemes rely on fine-scale topographic scaling parameters and low-resolution wind speed as input. While one scheme, referred to as the “wind scheme”, further necessitates fine-scale vertical wind components, a second scheme, referred to as the “aspect scheme”, does not require fine-scale temporal input. We achieve this by additionally downscaling near-surface vertical wind speed solely using topographic scaling parameters and low-resolution wind direction. We assess the performance of our downscaling schemes using an independent subset of the model database on simulated topographies, model data on actual terrain, and spatially measured new snow depth obtained through a photogrammetric drone survey following a snowfall event on previously snow-free ground. While the assessments show that our downscaling schemes perform well (relative errors ≤ ±3% with modeled and ≤ ±6% with measured snowfall deposition), they also demonstrate comparable results to benchmark downscaling models. However, our schemes notably outperform the benchmark models in representing fine-scale patterns. Our downscaling schemes possess several key features, including high computational efficiency, versatility enabled by the comprehensive model database, and independence from fine-scale temporal input data (aspect scheme), indicating their potential for widespread applicability. Therefore, our downscaling schemes for near-surface snowfall and vertical wind speed can be beneficial for various applications at fine grid resolutions such as in atmospheric and climate sciences, snow hydrology, glaciology, remote sensing, and avalanche sciences.

Lesser Antilles slab reconstruction reveals lateral slab transport under the Caribbean since 50 Ma

The link between surface tectonic plates and mantle slabs is fundamental for paleo-tectonic reconstructions and for our understanding of mantle dynamics. Many seismic tomography-based studies have assumed vertical slab sinking and projected mantle features to the surface to reconstruct paleo-trench locations or explain tectonic features. Here, we used a slab-unfolding approach that does not require assumptions about sinking paths or rates to re-interpret the seismic structure of the Lesser Antilles slab underneath the Caribbean. A recent study invoked mainly vertical slab sinking and a highly folded and deformed slab to explain seismic Caribbean mantle structures. However, our results show that the upper-mantle Lesser Antilles slab structure can be better explained by limited intra-slab deformation and up to ∼900 km lateral slab transport towards the northwest after subduction. Our results indicate that such lateral slab transport can occur even with probable weaknesses in the slab that originate from a subducted fossil ridge-transform system. We ascribe the lateral slab transport in the mantle to a kinematic connection with the North American plate, which has migrated northwestward since the Eocene.

Preliminary study of the effect of low-intensity focused ultrasound on postpartum uterine involution and breast pain in puerperal women: a randomised controlled trial

To evaluate the safety and efficacy of low-intensity focused ultrasound (LIFU) therapy in facilitating fundus descent and relieving postpartum breast pain compared with sham treatment. A multicentre, randomised, sham-controlled, blinded trial was conducted. A cohort of 176 eligible participants, who had normal prenatal check-ups and met the inclusion and exclusion criteria, were recruited from three medical centres and subsequently randomized into either the LIFU or sham group. All participants received three treatment sessions, wherein LIFU signal was applied to the uterus and breast sites using coupling gel, with the absence of ultrasound signal output in the sham group. Fundal height measurement and breast pain score were performed after each treatment. The primary outcome, uterine involution, was presented by measuring the fundal height of the uterus. The visual analogue scale (VAS) score, as a secondary outcome, was used to assess breast pain and determine the correlation between breast pain and fundal height as the outcome simultaneously. All participants were randomly assigned to either the LIFU group (n = 88) or sham group (n = 88), with seven individuals not completing the treatment. Overall, a statistically significant difference was noted in the rate and index of fundus descent after each treatment. The rate and index of fundus descent showed greater significance following the second treatment (rate: 1.5 (1.0, 2.0) cm/d; index: 0.15 (0.1, 0.18), P < 0.001) and third treatment (rate: 1.67 (1.33, 2.0) cm/d; index: 0.26 (0.23, 0.3), P < 0.001) in the LIFU group. VAS scores, which were based on the continuous variables for the baseline, first, second, and third treatments in the LIFU group (2.0 (2.0, 3.0), 1.0 (0.0, 2.0), 0.0 (0.0, 1.0), and 0.0 (0.0, 0.0) points, respectively), and the sham group (2.0 (2.0, 2.0), 2.0 (1.0, 2.0), 2.0 (1.0, 3.0), and 3.0 (1.0, 3.0) points, respectively), showed a statistically significant difference between the two groups. Meanwhile, the discrepancies in VAS score classification variables between the two groups were statistically significant. After the third treatment, a notable correlation was observed between the VAS score decrease and fundus descent rate; the more the VAS score decreased, the faster was the fundal decline rate in the LIFU group. LIFU therapy is safe and effective, contributing to the acceleration of uterine involution and the relief of postpartum breast pain.Trial ID The study has registered in the Chinese Clinical Trial Registry (ChiCTR2100049586) at 05/08/2021.

CeF3-TbF3-YF3 nanoparticles for ratiometric temperature sensing

The Ce0.5Y0.5-XTbXF3 (X = 0.01, 0.02, 0.05, 0.1, and 0.5) nanoparticles demonstrated a single-phase hexagonal structure corresponding to CeF3 host. The average diameter was 15 ± 1 nm. Under Ce3+ excitation at 266 nm, the luminescence peaks of (5d – 4f) Ce3+ and 5D4 – 4FJ (J = 6, 5, 4, and 3) Tb3+ were observed. The emission peaks from 5D3 level of Tb3+ were not observed. We took the luminescence integrated intensity ratio (LIR) of Ce3+ and Tb3+ peaks as a temperature-dependent parameter (303–523 K range). The LIR functions decay with the temperature increase. Indeed, with the temperature rise, the depopulation rate of Ce3+ excited state by Tb3+ becomes higher (phonon-assisted process). Thus, the ICe/ITb decreases. However, the rate of the LIR decay decreases with the increase of Tb3+ concentration. It was suggested, that this phenomenon is related to the presence of two competing processes populating the 5D4 state of Tb3+. There are phonon-assisted non-radiate transition from 5D3 to 5D4 of Tb3+ and cross-relaxation between Tb3+ ions, which was considered less temperature-dependent. The contribution of less temperature-dependent cross-relaxation process to the population of 5D4 increases with the Tb3+ concentration increase compared to 5D3 – 5D4 non-radiative transition. More significant contribution of the cross-relaxation leads to the decrease in the LIR descent rate. The maximum Sa and Sr values were 0.19 K-1 and 1.74 %/K at 303 K, respectively.

Cost accounting and economic competitiveness evaluation of photovoltaic power generation in China —— based on the system levelized cost of electricity

Accelerating the penetration of photovoltaics (PV) oriented renewables is a vital mainstay in climate mitigation. Along with continuous growth of PV generation in the power system, PV costs have been rapidly declining. Levelized cost of electricity (LCOE) is commonly applied to cost accounting of energy, while neglecting the specific cost compositions of PV leads to an overly optimistic scenario. By integrating grid costs and balancing costs into conventional LCOE framework, a System LCOE (S-LCOE) model was constructed to evaluate the economic feasibility of PV generation, more accurately. The results revealed that all provincial S-LCOE of China's PV is currently higher than local desulfurized coal electricity price (DCEP). Based on the comparative analysis of provincial S-LCOE and DCEP, four regions with diverse economic competitiveness were identified. PV projects in Region I and Region II are considered to be potentially competitive comparing to thermal generation, in terms of environmental benefits and S-LCOE, especially in Guangdong, Jilin, and Hainan. Furthermore, by simulating the descent trajectory of S-LCOE, we estimate that China will achieve S-LCOE equal to DCEP in Region I as early as 2023, while it will be postponed to 2042 in Region Ⅳ at the latest, depending on different S-LCOE descent rates.

Ekstrapolacija vertikalne brzine vetra korišćenjem statističkih pristupa

The wind power industry has experienced a significant increase and popularity in recent times, and the latest statistics indicate that this sector is still thriving. However, one of the essential steps in developing wind energy projects is finding suitable sites for wind farms, which involves understanding the nature of wind speed, wind direction, terrain, and environmental impacts. To predict the wind energy production over the expected lifespan of a wind farm, vertical wind speed extrapolation to the hub height of the wind turbine is necessary. Therefore, this study presents a comprehensive evaluation of seven statistical approaches for vertical wind speed extrapolation, including Generalized Linear Models (GLM), Linear Regression (LR), Support Vector Machines (SVM), Generalized Additive Models (GAM), Gaussian Process Regression (GPR), Regression Tree (RT), and Ensemble Regression (ER). The accuracy of these methods is assessed using performance metrics such as Mean Squared Error (MSE), Root Mean Squared Error (RMSE), Normalized RMSE (NRMSE), Normalized MSE (NMSE), Mean Bias Error (MBE), Mean Absolute Error (MAE), Mean Percentage Error (MPE), Mean Absolute Percentage Error (MAPE), Symmetric Mean Absolute Percentage Error (SMAPE), and R-squared (R2). The study concludes that, on average, GLM performs the best out of all seven statistical methods.

Phytoplankton size structures and their interactive effects with nutrient conditions on sinking rates in a mariculture system

Phytoplankton size structures and their interactive effects with nutrient conditions on sinking rates in a mariculture system

Cycling Rates of Particulate Organic Carbon Along the GEOTRACES Pacific Meridional Transect GP15

AbstractUnderstanding particle cycling processes in the ocean is critical for predicting the response of the biological carbon pump to external perturbations. Here, measurements of particulate organic carbon (POC) concentration in two size fractions (1–51 and &gt;51 μm) from GEOTRACES Pacific meridional transect GP15 are combined with a POC cycling model to estimate rates of POC production, (dis)aggregation, sinking, remineralization, and vertical transport mediated by migrating zooplankton, in the euphotic zone (EZ) and upper mesopelagic zone (UMZ) of distinct environments. We find coherent variations in POC cycling parameters and fluxes throughout the transect. Thus, the settling speed of POC in the &gt;51 μm fraction increased with depth in the UMZ, presumably due to higher particle densities at depth. The settling flux of total POC (&gt;1 μm) out of the EZ was positively correlated with primary production integrated over the EZ; the highest export occurred in the subarctic gyre while the lowest occurred in the subtropical gyres. The ratio of POC settling flux to integrated primary production was low (&lt;5%) along GP15, which suggests an efficient recycling of POC in the EZ in all trophic regimes. Specific rates of POC remineralization did not show clear variations with temperature or dissolved oxygen concentration, that is, POC recycling was apparently controlled by other factors such as microbial colonization and substrate lability. Particle cohesiveness, as approximated by the second‐order rate constant for particle aggregation, was negatively correlated with trophic regime: particles appeared more cohesive in low‐productivity regions than in high‐productivity regions.

Vertical Development Speed of Shallow Radiation Fog

Vertical Development Speed of Shallow Radiation Fog

干旱区谷子生长发育模拟模型的构建与评价

The establishment of crop growth models enables the simulation of the impacts of environmental changes on crop growth, providing theoretical guidance for exploring the relationship between environmental factors and crop growth. The model used the growth cycle (GC) as the simulation time step and was built upon four sub-models: topology, photosynthesis, biomass allocation, and geometric morphology. It was quantitatively utilized the concept of effective accumulated temperature (EAT) and parameters such as sink and expansion rate were used to explain the allometric growth relationships among different organs. The R2 values for the geometric morphological parameters such as leaf length, leaf width, leaf area, and internode volume ranged from 0.78 to 0.94, while the F-values for the regression equations ranged from 1533.53 to 13949.51. The R2 values for simulating leaf, internode, and earhead biomass were 0.62-0.94, 0.74-0.97, and 0.98, respectively, with RMSE values ranging from 0.02 to 0.13 g for leaf biomass, 0.03 to 0.13 g for internode biomass, and 1.71 g for earhead biomass. The results indicated that the model exhibited good performance and reliability in simulating the growth and development of leaves, internodes, and earheads. This provides a solid foundation for the development of a millet model with functional-structural feedback.

The Effect of Core Exercise Program on Vertical Jump, Speed, Agility and Strength Parameters in Junior Male Soccer Players

This study was conducted to investigate the effect of core exercise program on vertical jump, speed, agility and strength parameters in junior male soccer players. In the study, pretest-posttest control group design, one of the experimental models of quantitative research method, was used. The experimental group of the study consisted of 12 male soccer players (X̄year: 12,16±,83) who underwent core exercise 3 days a week for six weeks in addition to regular soccer training, while the control group of the study consisted of 12 male athletes (X̄year: 12,25±,62) who underwent only regular soccer training. Leg strength, core strength, vertical jump, 30 m sprint and agility tests were administered to the athletes who voluntarily participated in the study before and after six weeks of training. The normality level of the data was determined by Shapiro-Wilk test. Independent Sample T Test for independent groups and Paired Sample T Test for dependent groups were used to analyze the normally distributed data. According to the findings of the study, there was a statistically significant difference between the pre-test - post-test measurement values of all performance tests of the experimental group and core strength, vertical jump, 30 m sprint and agility tests of the experimental and control groups (p0.05), while no significant difference was found in the control group (p0.05). According to the results of the study, it can be said that the core exercise program applied to male football players has positive effects on the development of vertical jump, speed, agility and strength parameters.Keywords: Core exercise, Football, Jumping, Speed, Strength

Tau Theory-Based Flare Control in Autonomous Helicopter Autorotation

A novel trajectory generation and control architecture for fully autonomous autorotative flare that combines rapid path generation with model-based control is proposed. The trajectory generation component uses optical Tau theory to compute flare trajectories for both longitudinal and vertical speed. These flare trajectories are tracked using a nonlinear dynamic inversion (NDI) control law. One convenient feature of NDI is that it inverts the plant model in its feedback linearization loop, which eliminates the need for gain scheduling. However, the plant model used for feedback linearization still needs to be scheduled with the flight condition. This key aspect is leveraged to derive a control law that is scheduled with linearized models of the rotorcraft flight dynamics obtained in steady-state autorotation, while relying on a single set of gains. Computer simulations are used to demonstrate that the NDI control law is able to successfully execute autorotative flare in the UH-60 aircraft. Autonomous flare trajectories are compared to piloted simulation data to assess similarities and discrepancies between piloted and automatic control approaches. Trade studies examine which combinations of downrange distances and altitudes at flare initiation result in successful autorotative landings.