Structure Of System Research Articles

Deriving the PedsUtil health state classification system to measure health utilities for pediatric populations based on the PedsQL: a confirmatory factor analysis.

An important methodological challenge in conducting pediatric economic evaluations is estimating the preference-based health-related quality of life (HRQoL) of children. Current methods are highly variable and there is no single instrument available to value HRQoL consistently across multiple pediatric age groups. The Pediatric Quality of Life Inventory (PedsQL) is a non-preference-based generic HRQoL instrument validated for children 2-18 years, but it cannot be directly used in economic evaluations. The aim of this study was to establish the core dimension structure of the PedsUtil health state classification system using confirmatory factor analysis, which is the first step of deriving a preference-based measure of HRQoL based on the PedsQL. Four competing dimension structures of the PedsUtil health state classification system were developed based on published literature and expert opinion. Using data from the Longitudinal Study of Australian Children (LSAC) (n = 45,207), the 4 dimension structures were evaluated using the robust weighted least squares estimation method. The analyses were stratified by 2-year age intervals (from 2 to 17 years) to reflect the study design of the LSAC, as well as special healthcare needs status of the child. Model fit was evaluated by examining standardized factor loadings and various fit indices including the comparative fit index (CFI), Tucker-Lewis Index (TLI), and the root mean square error of approximation (RMSEA). Modification indices and residual correlations were examined to re-specify the models to improve model fit when necessary. The findings supported a 7-dimension structure (i.e., Physical Functioning, Pain, Fatigue, Emotional Functioning, Social Functioning, School Functioning, and School Absence) of the PedsUtil health state classification system. The 7-dimension model exhibited adequate fit across subgroups with CFI values that ranged from 0.929 to 0.954, TLI values from 0.916 to 0.946, and RMSEA values from 0.058 to 0.102. This study established the core dimension structure of the PedsUtil health state classification system using confirmatory factor analysis. The 7-dimension structure was found to be applicable across diverse pediatric populations. Research is currently ongoing to select the most representative item within each dimension of the PedsUtil health state classification system and valuation surveys will be fielded to estimate the PedsUtil scoring system.

Male reproductive system of the deep-sea acorn worm Quatuoralisia malakhovi (Hemichordata, Enteropneusta, Torquaratoridae) from the Bering Sea

BackgroundThe deep-sea acorn worm Quatuoralisia malakhovi belongs to the phylum Hemichordata, class Enteropneusta, family Torquaratoridae, which was described in 2005. Owing to their epibenthic lifestyle and deep-sea habitat features, torquaratorids differ anatomically from shallow-water acorn worms; however, their morphology and fine structure are poorly studied. We have the opportunity to make three complete detailed series of histological sections of Q. malakhovi and to study the microscopic anatomy, histology and fine structure of the reproductive system of this acorn worm using scanning and transmission electron microscopy.ResultsThe sexes of Q. malakhovi are separate and indistinguishable externally. The lobed testes occupy the dorsal side of the genital wings and distinctly bulge into the peribranchial cavity by their mature lobes. The central part of the testis is always submerged into the genital wing and opens via a single gonad pore. The monociliary muscle cells stretch along the external wall of the testis and surround the gonad pore, probably taking part in the contraction of the testis lobes for spawning. The germinative epithelium of the testis contains spermatogenic cells at different stages of development and interstitial cells. Yolk cells are not found. Interstitial cells embrace the spermatogonia and spermatogenic columns, providing horizontal compartmentalization of the germinative epithelium, and contain numerous phagosomes with remnants of degenerating spermatogenic cells. The testis wall contains haemal lacunae, which are usually located on the side opposite the gonad pore. We describe the fine structure of spermatogonia, spermatocytes clustered in spermatogenic columns, spermatids, and spermatozoa. Spermatozoa are of the ectaquasperm type and consist of an acorn-shaped head and a flagellum 18–25 µm long. The sperm head includes a beak-shaped acrosomal part, a spherical nucleus and a midpiece containing a ring of 5 or rarely 6 mitochondria.ConclusionsThe male reproductive system and sperm structure of Q. malakhovi, a representative of the family Torquaratoridae, have a number of differences from shallow-water acorn worms; however, the spermatogenesis and sperm structure of Q. malakhovi generally follow the pattern of the other three enteropneust families, and the phylogenetic significance of these deviations should be the subject of further research.

Myelodysplasia Rehabilitation in Children: a Review

INTRODUCTION. 1.5 thousand children with myelodysplasia (MD) are born in Russia every year. To improve the quality of life, most of them need lifelong medical supervision and rehabilitation. The topic of medical rehabilitation in MD in children is poorly covered. AIM. To search and analysis published data on the rehabilitation of children with MD identify the most effective methods. MATERIALS AND METHODS. The collection and analysis of publications on this topic from the PubMed and eLibrary databases published from 2014 to 2024 was carried out. Earlier fundamental works on secondary disorders in myelodysplasia and Spina bifida were also included in the review. A total of 512 publications in PubMed and 1096 publications in eLibrary were analyzed, 584 of them were unique. Publications of reviews, systematic reviews and clinical observations were included. RESULTS AND DISCUSSION. Rehabilitation for MD in children is multidisciplinary in nature, a violation of the structure of the nervous system entails, already in utero, the formation of deformities of the musculoskeletal system, combined changes in the functioning of the lower urinary tract and intestines. It is known that rehabilitation started from an early age helps to master motor skills in a timely manner, contributes to the prevention of metabolic syndrome, contractures, pressure sores, urodynamic disorders and constipation. There are different approaches regarding the intensity of physical activity during the day and week, following the recommendations of the World Health Organization (WHO), children should exercise for more than 60 minutes a day. Physical exercises should be carried out from the perspective of the concept of neuroplasticity and enhanced by the influence of magnetic stimulation, low-intensity laser, electromyostimulation, vibration therapy. It will be possible to effectively use acupuncture and massage. In addition, it is important to include urological and orthopedic care in medical rehabilitation from an early age. CONCLUSION. Due to the high disability, there is a question of effective methods for improving rehabilitation potential and improving the standard of living. Among the described methods, physiotherapy is distinguished, including therapeutic exercises, magnetic stimulation, low-intensity laser therapy, electromyostimulation, and ergotherapy. It is necessary to continue to study the effectiveness of the use of various physical factors in children with MD.

Design of geostationary orbit ultrawide FOV long-wave infrared imaging spectrometer

The geostationary orbit imaging spectrometer offers distinct advantages for diverse applications in remote sensing. To enhance swath and data richness, there is a growing trend toward spectrometers with broader fields of view (FOV) and extended slit lengths. Optical systems equipped with these features face significant challenges in aberration correction. This paper investigates the parameters of geostationary orbits and designs a spectroscopic system capable of achieving ultrawide FOV without the need for stitching spectrograph subsystems. Additionally, it also designs a front-end telescope system that matches the spectroscopic system. The spectroscopic system features a slit length of 240 mm, employing an enhanced Offner structure for a long slit spectroscopic system, incorporating a freeform surface on the third mirror. To inhibit the effects of radiation stray light, the system's exit pupil is controlled to be positioned in front of the image plane to facilitate matching with the cold shield. The analysis indicates that the spectral resolution of the long-wave infrared imaging spectrometer system is 50 nm, with a total of 90 spectral sampling channels. The system's spatial resolution is 100 m, enabling a swath width of 400 km. Furthermore, the modulation transfer function (MTF) exceeds 0.42 at the Nyquist frequency of 8.35 lp/mm. The maximum RMS radius of the system is less than 27 μm at wavelengths ranging from 8 to 12.5 μm.

Abdominal aortic aneurysm repair in Sweden vs. Finland: benefits of population-wide screening.

In 2006, screening of 65-year-old men for abdominal aortic aneurysm (AAA) was started in Sweden. Decline in aneurysm-related mortality has been reported since, but aneurysm incidence has been diminishing globally. Neighbouring Finland with similar population structure and health care system has no AAA screening programme. The aim of this study was to compare incidence and results of AAA repair in Sweden and Finland to differentiate the effect of screening from other changes in the epidemiology and treatment of AAA. All repairs for intact AAA (iAAA) or ruptured AAA (rAAA) from 1998 to 2017 were identified from national registers, and mortality data for these patients were collected. A total of 15 927 operations for iAAA were performed in Sweden and 6933 in Finland. In Sweden, the yearly operation volume increased after introduction of screening. Both countries showed a decrease in number of rAAA operations, but the decrease was more pronounced in Sweden. Sweden had a higher proportion of all AAA repairs because of rupture in the start of the study but by the end, the proportions were similar in both countries. Long-term survival improved for 65-79-old men in Sweden after start of screening. This study reveals improvements in results of AAA repair in Sweden. A decrease in rAAA repair and increase in iAAA repair were evident after AAA screening was started in 2006 and resulted in better outcomes. These changes are likely the result of AAA screening as they cannot be seen in neighbouring Finland that is lacking an AAA screening programme.

Passive control and damage assessment with a pendulum tuned mass damper using mean square equations and second-order eigen-perturbation techniques

This paper proposes a novel framework for damage detection and retuning of a Pendulum Tuned Mass Damper (PTMD) addressing effects of stochasticity via mean-square equations and establishing rapid change detection. The framework was made possible via a Stochastic Differential Equation (SDE) formulation of the equations of motion considering a two degree of freedom base and structure system equipped with a PTMD. The system was assumed to be excited at the base with Gaussian white noise and the solutions were computed using a stochastic integration scheme. A Second Order Eigen-Perturbation (SOPS) estimate is used to carry out detection of sudden stiffness reduction in the base floor of the structure. Once damage is detected, mean square equations on monitored displacements were used to retune the PTMD by adapting the length of the pendulum. It was found that damage could be detected rapidly and successive retunings were able to minimize the mean square displacement of the damaged structure and stabilise it over time.

Reliability optimization of reliability-redundancy allocation problems based on K-mixed strategy

In a reliability-redundancy allocation problem (RRAP), system reliability is maximized by selecting component reliabilities and finding the most suitable redundancy of subsystems. The advantages of a K-mixed strategy were introduced by modeling, so as to better improve system reliability. Compared with other existing redundancy strategies, the performance of a K-mixed strategy was verified using redundancy allocation problems (RAP). In this study, for the first time, a reliability calculation model under the new structure ( [Formula: see text] = 2 and [Formula: see text] = 1) is proposed, and the K-mixed strategy under the new structure is used in the reliability-RAP (RRAP), which is more complex than the RAP and further saves the production cost. In practical optimization, there was a complex decision-making problem to ensure optimal system reliability while minimizing system volume, weight, and cost. Then, this K-mixed strategy was adopted for modeling three benchmark problems in RRAP to seek a better and more flexible system structure. A powerful evolutionary algorithm (NSGA-II) was used to solve the new RRAP model to obtain the best system structure and reliability. The advantages of this model were confirmed by comparison with results from previous reliability optimization studies. The results show that the cost-saving advantages of the new structure in ensuring maximum reliability are significant. All the optimized remaining costs are noticeably higher than those of other methods, with the cost savings of the series-parallel system being the greatest. The difference in remaining costs compared to previous optimizations remains in the tens. Moreover, in more complex systems (Complex bridge system), the advantage in remaining volume is very significant, with the improvement being three times that of the optimization results of other methods.

Neural relational and dynamics inference for complex systems

Many complex processes in the real world can be viewed as complex systems and their evolution is governed by underlying nonlinear dynamics. However, one can only access the trajectories of the system without knowing the underlying system structure and dynamics in most cases. To address this challenge, this paper proposes a model called Neural Relational and Dynamics Inference (NRDI) that combines graph neural networks (GNNs) and ordinary differential equation systems (ODEs) to handle both continuous-time dynamics prediction and network topology inference for complex systems. Our model contains two modules: (1) the network inference module, which infers system structure from input system trajectories using GNNs, and (2) the dynamics learning module, which employs GNNs to fit the differential equation system for predicting future trajectories. We tested NRDI’s performance on system trajectory prediction and graph reconstruction separately. Experimental results show that the proposed NRDI outperforms many baseline models on continuous-time complex network dynamics prediction, and can explicitly infer network structures with high accuracy.

Numerical investigation on the heat dissipation of phase change materials used in the high-speed train brake system

The massive heat dissipation demands of the brake system in high-speed trains pose a significant obstacle to achieving higher operation speeds. Phase change material has attracted considerable attention in various fields due to their exceptional heat dissipation capabilities, yet their utilization in the brake system of high-speed trains remains unexplored. This study aims to investigate the feasibility of phase change material application in the brake system of high-speed train. Specifically, in Case A, the introduction of phase change material resulted in a notable 21% decrease in the average temperature and a remarkable 40% reduction in the maximum temperature difference within the brake system. The latent heat of the phase change material plays a crucial role in maintaining a substantial temperature differential between the cooling components and discs, thereby enhancing heat flux in the brake system. Phase change materials exhibit superior cooling performance compared to traditional air cooling methods in the brake system. To expedite the cooling process of phase change material and facilitate its transition from liquid to solid, an optimized brake system structure utilizing phase change material was proposed. This optimized design holds promise in enhancing the overall heat dissipation efficiency of the high-speed train brake system.

Electrical stimulation improves the efficiency of treating typical reclaimed water in biofilters

ABSTRACT To conduct advanced treatment on reclaimed water with a low C/N ratio and a low content of biodegradable organic matter, this paper established an electrically coupled biological filter system (biofilter-microbial electrolysis cell, BF-MEC). Through two-stage influent, the influence of electrical stimulation and electrochemical structure on the nitrogen and carbon removal of the system was explored, and the following results were obtained. The optimal externally applied voltage for the BF-MEC system is 0.55 V. The optimal structure of the BF-MEC system is an electrode spacing of 100 mm, and the optimal electrode position is when the electrode is located at the bottom of the system. Compared with the BF system, in the first stage, the removal rates of chemical oxygen demand, total ammonia nitrogen (TAN), and total nitrogen (TN) in the optimal structure BF-MEC system are increased by 13.4, 118.1, and 273.65%, respectively. In the second stage, COD, TAN, and TN removal rates are increased by up to 277.98, 115, and 722.98, respectively. The optimal electrode position is when the electrode is located at the lower part of the system. At this time, the microbial community is more abundant, the microbial activity and lifespan are longer, and the system efficiency is optimal. optimal.

Fundamental study on the difference between materials and vibration conditions in piezoelectric vibration power generation using electromechanical coupling phenomena

Conventionally, vibration energy and sound energy are emitted as noise and vibration. We have proposed a system that converts the vibration of the plate into energy. In this study, a circular plate of constant thickness, on which a piezoelectric element was installed, was adopted as the host structure of an energy-harvesting system. The plate was supported at its elastic end, which was intermediate between simple and clamped supports, and was subjected to a harmonic point force. The piezoelectric performance of the system was highly dependent on the vibration characteristics of the plate. Regarded as one of the representative vibrational characteristics, the natural frequency of the plate was affected by the materials, excitation positions, and vibration modes of the plate. Therefore, the plate materials varied the natural frequency, thus affecting the conversion of vibration energy into electrical energy through the piezoelectric effect. In this study, we investigated plates made of selected materials commonly used in industry and tested different excitation conditions. As the result, we clarified that the proposed system is almost unaffected by the material of the plates, and it was shown to be useful.

Experimental and numerical study on dynamic responses of a TLP-type modular floating structure system

This paper explores a proposed TLP-type modular floating structure system, incorporating both central TLP modules and peripheral floating artificial reef modules. The outermost floating artificial reef module can function as a floating breakwater, and also serving as a habitat for surrounding marine organisms. To assess the system's multi-body coupling dynamics under various wave conditions, both scale model tests (1:80) and time-domain numerical simulations were performed. The simulations accounted for hydrodynamic interactions among the bodies and the mechanical coupling effects. During the scale model test, a survival strategy has been proposed to prevent collision risks between reef modules and adjacent TLP modules, which involving a hinge connector with additional linear spring. A preliminary stiffness recommendation was suggested by a trade-off between the pitch of the reef module and the spring force. Numerical and experimental results have been widely compared and discussed, including the multi-body motion responses and the tension leg loads. A good agreement has been achieved, although responses are slightly overestimated by numerical simulation due to the neglect of the viscous damping effect. In addition, the responses of the proposed system, connected with and without the outermost floating artificial reef module, have been compared and analyzed. The results suggest that the connection of the reef module can significantly reduce the system's surge response and enhance its survivability under severe sea conditions. The validated numerical model can serve as a valuable reference for subsequent system optimization and further engineering applications.

Self-assembly core–shell hollow fly ash sphere-bridged Ti3C2Tx MXene 3D spherical/ lamellar composites with specific electromagnetic wave absorption performance

A new A/B spherical/lamellar electromagnetic wave absorption (EWA) model was established, in which A phase was a spherical material with low dielectric constant and B phase was a lamellar 2D material with high dielectric constant. Insulative fly ash cenospheres (FA) and conductive Ti3C2Tx flakes were selected as the A phase and the B phase which acted as the framework (as well as core) and the interface builder (as well as shell) respectively to construct the novel 3D connected structure system via simple self-assembly. FA, a cheap power plants solid waste, was used as an insulating bridge for Ti3C2Tx to help to adjust the conductivity, the electromagnetic parameters and the impedance matching. The synergistic effect of the special heterogeneous structures and the moderate composition of FA and Ti3C2Tx endowed the composites with controllable complex permittivity and excellent EWA performances. FA@T0.35 exhibited a RLmin of − 50.94 dB at 3.5 mm and its widest EAB was 4.25 GHz at 2.0 mm. FA@T0.40 reached a RLmin of − 45.13 dB with an EAB of 4.03 GHz at 2.0 mm. The widest EAB was 4.19 GHz at only 1.5 mm. The work offers a new guideline for designing a high-performance EWA material by using waste materials.

Electric vehicle power system in intelligent manufacturing based on soft computing optimization

Soft computing technology has attracted extensive attention in computer engineering and automatic control domains because it can deal with uncertainties, fuzziness, and complex practical problems. This study adopts a Genetic Algorithm (GA) in soft computing technology to realize the cooperative optimization of electric vehicle's dynamic and economic performance. The advantage of soft computing technology lies in its adaptability to uncertainty, fuzziness, and complex practical problems, making GA an effective tool for solving complex optimization problems. Firstly, the electric vehicles' power system structure and energy management strategy are investigated and analyzed. Secondly, the improved non-dominated sorting genetic algorithm II (NSGA-II) is selected to optimize the parameters of electric vehicles because of its simple operation and high optimization accuracy. Thirdly, NSGA-II is used to construct the electric vehicles' power and energy configuration, with power and economic performance as the main optimization objectives. Meanwhile, a fuzzy logic controller is designed to adjust the parameters of GA online, so that the optimization process is closer to the actual operating conditions. Finally, the relevant variables are selected to achieve the optimization goal, the optimization objective function and constraint conditions are established, and the model is simulated and evaluated. The results show that the optimized electric vehicle's acceleration time is remarkably reduced, the dynamic performance is improved by more than 7 %, and the power loss is reduced by 5 %. In addition, compared with the current multi-objective optimization model, this model enables electric vehicles to travel longer distances under the same power. This study provides a new idea and method for the performance optimization of electric vehicles. Moreover, it offers a valuable reference for the innovation and development of electric vehicle technology in the intelligent manufacturing field. This study indicates that electric vehicles could be more efficient, energy-saving, and environmentally friendly to serve people's travel needs in the future.

Development of an expert system for technological support of required roughness when machining hardened steel parts on numerically controlled machines

This work addresses the problem of improving the surface quality of parts of rotation bodies, which are made of hardened steels, in the course of their machining on lathes with numerical program control. The research object was the surface roughness of parts. The methodology involved system analysis and synthesis, artificial neural networks, fuzzy logic, experiment, and processing of experimental results. A decomposition scheme for the expert system structure was developed, which can be used as the basis for formulating requirements to a future expert system for monitoring and prediction of roughness parameters. It was established that the models currently applied to describe the relationship between surface quality and the technological regimes used to ensure the technological level of roughness give a high error of over 20%. The possibility of using models that apply artificial intelligence and contain neural network blocks and decision-making devices based on fuzzy logic is substantiated. It is shown that such a combination makes it possible to customize the system for processing parts of a certain production range, as well as a more correct assessment of the onset of catastrophic wear of cutting tools. The neuro-fuzzy model was confirmed to have an error of less than 10%, which is significantly lower than when using spectral or correlation models. According to the testing results, the proposed expert system for monitoring and prediction of roughness parameters enables a 2.5-fold reduction in the scatter of roughness parameters under an increase in tool wear, compared to without its application. Thus, the proposed system makes it possible to assess the level of cutting tool wear more correctly and determine the onset of its limit state.

Improving the organization of medical care for patients in the specialty of medical rehabilitation in the Tomsk oblast

More than a third of the total population of the planet needs medical rehabilitation and the need will increase in the future. The prospective increase in life expectancy by the middle of the 21st century will be accompanied by an increase in the share of malignant neoplasms and diseases of the circulatory system in the morbidity structure, and the level of injuries will remain unchanged. These factors will negatively affect a person’s functional capabilities and will contribute to an increase in disability, increasing the relevance of medical rehabilitation. In Russia, according to the current procedure, there is a three-stage organization of medical rehabilitation. The implementation of these stages is carried out within the regional territorial programs of state guarantees (TPSG) of free medical care to citizens, which limits the financial accessibility of the completed cycle of medical rehabilitation for patients, due to budgetary allocations and the compulsory health insurance program, negatively affecting the quality of care provided. The article assesses the volume of medical rehabilitation provided in inpatient settings in the TPSG of the Tomsk oblast for the period of 2019–2022. Currently, three medical organizations in the region of different forms of ownership provide medical rehabilitation. In total, over a four-year-period, 8,804 cases in the specialty of medical rehabilitation were completed in the amount of 378.9 million rubles. An underfulfillment of the volume and costs of medical care during medical rehabilitation approved by the TPSG was recognized, as well as an outflow of patients for treatment to other regions (1,864 people during the study period). The most popular clinical and statistical groups (CSG) for which residents of the Tomsk oblast need rehabilitation measures have been identified, and organizational ways to improve the profile of this medical care have been substantiated.

Using Er/Cd-Codoped Bi4O5Br2 Microspheres to Enhance Antibiotic Degradation under Visible Illumination: A Combined Experimental and DFT Investigation.

High levels of antibiotic accumulation and the difficulty of degradation can have serious consequences for the environment and, therefore, require urgent attention. To solve this problem, a synergistic Er and Cd ion-codoped Bi4O5Br2 photocatalyst was proposed. The degradation rate of sulfamethoxazole (SMX) by Er/Cd-Bi4O5Br2 was eight times higher than that of pure Bi4O5Br2, exceeding that of single Er-doped or Cd-doped Bi4O5Br2, which was attributed to the ability of Er/Cd-Bi4O5Br2 to generate a variety of free radicals. Experimental results and theoretical calculations suggested a possible mechanism for the improved photocatalytic degradation rate. The reduction of the band gap can facilitate the production of electron-hole pairs, which play a significant role in the production of reactive radicals. Furthermore, an optimal stabilized structure of the ErCd-Bi4O5Br2 dopant system was identified based on the formation energy formulas of different ligand configurations. These findings offer promising potential for the degradation of broad-spectrum antibiotics and provide valuable insights for the design and modification of photocatalytic materials.

Информационные системы налоговых органов как инструмент предупреждения и разрешения налоговых споров

The article reveals the stages of digital transformation of the tax authorities of the Russian Federation. The main directions for the development of information tools of tax authorities in the field of tax Diptych and pre-trial consideration and resolution of tax disputes are indicated. The structure of the central information system of tax authorities - AIS «Tax-3» and one of its applied subsystems - the information resource «Tax Disputes» is analyzed. An analysis of this information resource is presented from the point of view of the functionality of its use in constructing samples of data sets to identify the causes of tax disputes and formulate measures to eliminate them based on them. Potential directions for further modernization of the information resource «Tax Disputes» are indicated.

Uncertainty and Latin Hypercube Sampling in Geotechnical Earthquake Engineering

A soil–foundation–structure system (SFSS) often exhibits different responses compared to a fixed-base structure when subjected to earthquake ground motion. Both kinematic and inertial soil–foundation–structure interactions can significantly influence the structural performance of buildings. Numerous parameters within an SFSS affect its overall response, introducing inherent uncertainty into the solution. Performing time history analyses, even for a linear elastic coupled SFSS, requires considerable computational effort. To reduce the computational cost without compromising accuracy, the use of the Latin Hypercube Sampling (LHS) technique is proposed herein. Sampling techniques are rarely employed in soil–foundation–structure interaction analyses, yet they are highly beneficial. These methodologies allow analyses determined by sampling to be conducted using commercial codes designed for deterministic analyses, without requiring any modifications. The advantage is that the number of analyses determined by the sampling size is significantly reduced as compared to considering all combinations of input parameters. After identifying the important samples, one can evaluate the seismic demand of selected soil–foundation–bridge pier systems using finite element numerical software. This paper indicates that LHS reduces computational effort by 60%, whereas structural response components (translation, rocking) show distinct trends for different systems.

An investigation on main effects and interactions of relative age effects and playing position in female elite football in Germany.

Athlete age-grouping and age-banding has been shown to impact sport participation and athlete development. The current study examined the impact of within-year (WYEs) and between-year effects (BYEs), and their interactions with playing position, on female participation in elite German football. The sample of 1,378 German first-league players revealed expected participation inequities within-year with relatively older players being over-represented and younger players being under-represented. From a between-year perspective there were no participation differences. The interaction of WYEs and BYEs revealed an over-representation of odd-year players in Q1, and Q2 in even years. With respect to the interaction between year effects and playing position, for WYEs the expected effect was present for goalkeepers and defenders, while there was no significant interaction for BYEs. Overall, the results offer insight regarding the impact of system structure on participation, and highlight unique characteristics associated with playing positions.