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Modal parameters (natural frequencies, mode shapes and modal damping) help to understand the dynamic behaviour of complex systems like machine tools. There are several approaches for finding the modal parameters. The Experimental Modal Analysis (EMA) has proven to be effective at standstill of a machine tool. The excitation, realized with impulse hammer or shaker, and excited responses at several locations are measured. Alternatively, the Operational Modal Analysis (OMA) can be deployed for finding the modal parameters during operation. Here, responses to excitation resulting from operation are only measured. The modal parameters are mathematically identified from the measured signals in both cases but with different methods. This paper discusses, to what extent both approaches (EMA and OMA) can lead to plausible identification of natural frequencies of a machine tool during milling. Concerning the EMA, attention is paid to capturing the excitation. Process forces can be assumed to be the most significant excitation. However, there are other excitation sources beside the process forces (e.g. drives, hydraulic and pneumatic aggregates), which are considered by this assumption to be a part of disturbances with consequence for the identification of the modal parameters. Regarding the OMA, attention is paid to the fact that the excitation is assumed to be broadband like the white noise. Unfortunately, this assumption does not match the characteristics of a real excitation. This paper contains the identification of natural frequencies of a machine tool during milling within both approaches. The achieved results are compared and discussed. [ABSTRACT FROM AUTHOR]

Hydrodynamic linear guides in machine tools offer a high load capacity and excellent damping characteristics, improving stability, precision, and vibration reduction. This study builds on previous research where floating heights were verified with a simulation model limited to measured floating heights. Advancements include incorporating pressure sensors into a fixed steel rail, enabling simultaneous measurement of oil film pressure and floating heights for a comprehensive understanding of lubrication conditions within the lubrication gap. The experimental results explore the effects of different lubrication methods, providing valuable insights into cavitation and lubrication adequacy. The results demonstrate the feasibility of utilizing pressure sensors to measure oil film pressure within the lubrication gap, providing a nuanced understanding of lubrication dynamics. By measuring both floating heights and pressure measurement, distinctions between hydrodynamic lubrication, mixed friction regions, and instances of lubricant deficiency become readily discernible. The variations in real-time oil film pressure and floating heights help to optimize the lubrication cycle for hydrodynamic linear guides, enhancing system performance and longevity. [ABSTRACT FROM AUTHOR]

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Due to new requirements regarding the efficiency of electrical machines it is necessary to steadily improve machine concepts or create new ones. Therefore, manufacturing technology has to be continuously improved, adapted or developed new. Forming technology offers an excellent opportunity to implement components for highly efficient electrical machines through its advantages regarding high productivity and high degree of material usage. This paper presents a new method for bending complete stacks of grain oriented electric sheets for use as radially laminated modules in an innovative machine concept with flux barriers. First, the principle of electric drives with flux barriers and the arrangement of the new radial lamination are explained. Then, practical preliminary studies concerning the bending of single sheets are performed. Based on this, the process and tooling for bending of pre-stacked sheets is developed and analysed. Accordingly, an increase in material utilisation of about 30% can be expected compared to classically designed stators. Furthermore, the use of the radially laminated stator principle increases the slot area by about 20% which makes it possible to insert more copper into the slot and thus increase the efficiency of the machine during operation. After validation of the process chain with a demonstrator motor and description of several manufacturing and quality improvements, finally, an outlook is given, and possible further research approaches are discussed. [ABSTRACT FROM AUTHOR]

After grinding of hardened workpieces, especially in case of safety-relevant components, usually non-destructive testing is carried out to detect thermo-mechanical damages in the surface layer. In-process detection methods allow a fast reaction to negative changes before producing a large amount of rejects and open the possibility to save additional time for post-process inspection. However, these are not industrially used yet, since boundary conditions and application limits are not defined so far. This study shows the potential of a grinding process control based on a soft sensor combining a thermal limit in a P c ′ ′ − Δt-diagram and magnetic Barkhausen noise analysis applied in-situ during grinding (BN). The specific grinding power P c ′ ′ in dependence of the contact time Δt allows to identify/avoid grinding burn starting from light tempering zones. Furthermore, the BN is well suited for the detection of detrimental residual stress changes (tensile) occurring even before tempering zones are generated. The developed process control based on this combination optimizes the process parameters to prevent negative thermo-mechanical surface changes while keeping the productivity of the process as high as possible. The applicability is demonstrated for external cylindrical and non-circular grinding processes. Due to the radius varying over the workpiece circumference, the latter ones require special demands on signal evaluation, resolution and control speed. [ABSTRACT FROM AUTHOR]

Hollow embossing rolling is a promising forming technology for metallic bipolar plates because of the high achievable production rates. However, the simulation-based process optimization is impeded by the incremental forming character and modeling of fine channel structures, which leads to large model sizes and long computation times. This paper presents a shell-based finite element approach validated by experimental forming tests using a miniaturized test geometry with typical discontinuities and varying channel orientations. The rolling experiments demonstrated that implementing restraining tension effectively decreases wrinkling, allowing successful forming of the selected test geometry by hollow embossing rolling. It was found that representing the manufacturing-related decreased rolling gap combined with the rolling gap changes due to roll system elasticity in the numerical model is essential for model accuracy. An optimized model approach with spring-controlled rollers was developed, which considers the effect of load-dependent rolling gap changes. With this approach the applied model achieves sufficient model accuracy for technological process simulation and optimization. [ABSTRACT FROM AUTHOR]

While international climate policies now focus on limiting global warming well below 2 °C, or pursuing 1.5 °C, the climate modeling community has not provided an experimental design in which all Earth System Models (ESMs) converge and stabilize at the same prescribed global warming levels. This gap hampers accurate estimations based on comprehensive ESMs of the carbon emission pathways needed to meet such agreed warming levels, and of the associated climate impacts under temperature stabilization. Here, we apply the Adaptive Emission Reduction Approach (AERA) with ESMs to provide such simulations in which all models converge at 1.5 °C and 2.0 °C warming levels by iteratively adjusting their emissions. These emission-driven simulations provide a wide range of emission pathways and resulting atmospheric CO2 projections for a given warming level, uncovering uncertainty ranges that were previously missing in the traditional CMIP scenarios with prescribed greenhouse gas concentration pathways. Meeting the 1.5°C warming level necessitates a 40 % (model full range: 7 to 76 %) reduction in multi-model mean CO2-forcing equivalent (CO2-fe) emissions from 2025 to 2030, a 98 % (57 to 127 %) reduction from 2025 to 2050, and a stabilization at 1.0 (-1.7 to 2.9) PgC yr-1 from 2100 onward after the 1.5 °C target is reached. For the 2.0 °C warming level, CO2-fe emissions require a 47 % (8 to 92 %) reduction until 2050 and a stabilization at 1.7 (-1.5 to 2.7) PgC yr-1 from 2100 onward. The on-average positive emissions under stabilized global temperatures are the result of a decreasing transient climate response to cumulative CO2-fe emissions. This evolution is consistent with a slightly negative zero emissions commitment – initially assumed zero – and leads to an increase in the post-2025 CO2-fe emission budget by a factor 2.2 (-0.8 to 6.9) by 2150 for the 1.5 °C warming level and a factor 1.4 (0.9 to 2.4) for the 2.0 °C warming level compared to its first estimate in 2025. Our simulations highlight shifts in carbon uptake dynamics under stabilized temperature, such as a cessation of the carbon sinks in the North Atlantic and in tropical forests. On the other hand, the Southern Ocean and the northern high-latitude land remain carbon sinks over centuries after temperatures stabilize. Overall, this new type of target-based emission-driven simulations offers a more coherent assessment across climate models and opens up a wide range of possibilities for studying both the carbon cycle and climate impacts, such as extreme events, under climate stabilization. [ABSTRACT FROM AUTHOR]

In recent years, space agencies, such as the National Aeronautics and Space Administration (NASA) and European Space Agency (ESA), have expanded their research activities in the field of manufacturing in space. These measures serve to reduce limitations and costs through fairing size, launch mass capabilities or logistic missions. The objective, in turn, is to develop technologies and processes that enable on-demand manufacturing for long-term space missions and on other celestial bodies. Within these research activities, in-situ resource utilization (ISRU) and recycling are major topics to exploit local resources and save transport capacity and, therefore, costs. On the other hand, it is important to carefully consider which items can be brought and which must be manufactured on the Moon. Consequently, on-demand needs in future space missions are considered regarding frequency, raw material and required manufacturing processes according to investigations by ESA and NASA. In conclusion, manufacturing in space state-of-the-art shows a strong focus on additive processes, primarily considering semicrystalline or amorphous plastics. The subtractive processing of metallic or ceramic materials, in turn, currently represents a research gap. Consequently, an approach for in-situ resource utilization-based subtractive manufacturing in space is presented to supplement the existing processes. The latter uses a high-pressure jet of water, with regolith simulate as abrasive in suspension, being directed at the workpiece, which is moved to separate metal and glass. Proof-of-concept results are presented, including suitable process windows, achieved cutting geometries, as well as the effects of parameter variations on the system technology and consumables used. The focus of the investigations supplements the general requirements for the design of machine tools for space applications with inertial process-specific boundary conditions as a step towards higher technology maturity. [ABSTRACT FROM AUTHOR]

Given the use of high-strength steels to achieve lightweight construction goals, conventional shear-cutting processes are reaching their limits. Therefore, so-called high-speed impact cutting (HSIC) is used to achieve the required cut surface qualities. A new machine concept consisting of linear motors and an impact mass is presented to investigate HSIC. It allows all relevant parameters to be flexibly adjusted and measured. The design and construction of the test bench, as well as the mechanism for coupling the impact mass, are described. To validate the theoretically determined process speeds, the cutting process was recorded with high-speed cameras, and HSIC with a mild deep-drawing steel sheet was performed. It was discovered that very good cutting edges could be produced, which showed a significantly lower hardening depth than slowly cut reference samples. In addition, HSIC was numerically modelled in LS-DYNA, and the calculated cutting edges were compared with the real ones. With the help of adaptive meshing, a very good agreement for the cutting edges could be achieved. The results show the great potential of using a linear motor in HSIC. [ABSTRACT FROM AUTHOR]

Previously, a 2D simulation model for hydrodynamic linear guides with two reduction factors has been developed to calculate oil film pressure and floating heights/angle numerically. However, no method was available to verify the oil film pressure experimentally but only with floating heights measurement. Therefore, different pressure sensor's integration methods were tested in a stationary Plexiglas rail to measure fluid film pressure inside the lubrication gap. The pressure sensors were statically and dynamically calibrated. However, floating heights could not be measured with the preliminary used Plexiglas rail. This paper reports the suitable integration of pressure sensors into a stationary steel rail to compensate this drawback. It focuses on the measurement of pressure rise using pressure sensors inside the lubrication gap in combination with the floating heights. Experimental results have shown that the oil film pressure inside the lubrication gap can be measured using pressure sensors, which draw conclusions about cavitation and lack of lubrication. The variation of oil film pressure measured along the length of the carriage can be used to improve the simulation model i.e. the reduction factors. The pressure measurement can help to identify the lubrication conditions and further actions can be taken to improve the lubrication cycle. [ABSTRACT FROM AUTHOR]

This paper provides an overview of the development of a 3D formed and metal-based facade element that combines a custom design and solar thermal functionality. To achieve this, a novel simplified solar thermal collector structure was developed using formed sheet metal half-shells with an integrated channel structure on the inside and a special absorber coating on the outside. The sheet metal half-shells were manufactured by highly innovative incremental sheet forming (ISF), which allows seamless integration into existing facades. As a part of this paper, the initial test results on thermal efficiency and the energy accumulation of the new collector type are presented. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop a physical activity advisory system supporting the correct implementation of sport exercises using inertial sensors and machine learning algorithms. Specifically, three mobile sensors (tags), six stationary anchors and a system-controlling server (gateway) were employed for 15 scenarios of the series of subsequent activities, namely squats, pull-ups and dips. The proposed solution consists of two modules: an activity recognition module (ARM) and a repetition-counting module (RCM). The former is responsible for extracting the series of subsequent activities (so-called scenario), and the latter determines the number of repetitions of a given activity in a single series. Data used in this study contained 488 three defined sport activity occurrences. Data processing was conducted to enhance performance, including an overlapping and non-overlapping window, raw and normalized data, a convolutional neural network (CNN) with an additional post-processing block (PPB) and repetition counting. The developed system achieved satisfactory accuracy: CNN + PPB: non-overlapping window and raw data, 0.88; non-overlapping window and normalized data, 0.78; overlapping window and raw data, 0.92; overlapping window and normalized data, 0.87. For repetition counting, the achieved accuracies were 0.93 and 0.97 within an error of ±1 and ±2 repetitions, respectively. The archived results indicate that the proposed system could be a helpful tool to support the correct implementation of sport exercises and could be successfully implemented in further work in the form of web application detecting the user's sport activity. [ABSTRACT FROM AUTHOR]

Perfectly coated surfaces are an essential quality feature in the automotive and consumer goods industries. They are the result of an optimized, controlled coating process. Because entire assemblies could be rejected if Out-of-Specification (OOS) parts are installed, this has a severe economic impact. This paper presents a novel, line-integrated multi-camera system with intelligent algorithms for anomaly detection on small KTL-coated aluminum parts. The system also aims to automatize the previously used human inspection to a sophisticated and automated vision system that efficiently detects defects and anomalies on coated parts. [ABSTRACT FROM AUTHOR]

This paper presents a new approach to the structural integration of piezoceramics into thin-walled steel components for condition-monitoring applications. The procedure for integrating the sensors into metal components is described, and their functionality is experimentally examined with a 2 mm-thick steel sheet. The signal quality of the produced sensors is investigated in a frequency range from 100 Hz to 50,000 Hz and is compared with the results of piezo patches and strain gauges under the same conditions. The results show that due to a higher signal-to-noise ratio and a better coherence, the structurally integrated piezoceramics and the piezo patches are more qualified sensors for vibration measurement in the examined frequency range than the strain gauges. The measurements also indicate that the patches provide higher amplitudes for the frequency range up to 20 kHz. Beyond that, up to 40 kHz, the integrated sensors supplied higher amplitudes. The better signal quality in different frequency ranges as well as the different manufacturing and application methods can be interpreted as an advantage or disadvantage depending on the boundary conditions of the condition-monitoring system. In summary, structural integrated piezoceramics extend the options of monitoring technology. [ABSTRACT FROM AUTHOR]

The compensation of thermal errors in machine tools is one of the major challenges in ensuring positioning accuracy during cutting operations. There are numerous methods for both the model-based estimation of the thermal tool center point (TCP) deflection and for controlling the thermal or thermo-elastic behavior of the machine tool. One branch of thermal error estimation uses regression models to map temperature sensors directly onto the TCP-displacement. This can, e.g., be accomplished using linear models, artificial neural networks or characteristic diagrams. One of the main limitations of these models is the poor extrapolation behavior with regard to untrained load cases. This paper presents a new method for updating characteristic diagram based compensation models by combining existing models with new measurements. This allows the optimization of the compensation for serial production load cases without the effort of computing a new model. The new method was validated on a 5-axis machining center. [ABSTRACT FROM AUTHOR]

Output-only Modal Analysis makes it possible to investigate the dynamic behaviour of machine tools, especially under process conditions. The differences between standstill and process state, which are important to be considered, result from process damping, gyroscopic moments of the rotating spindle, and changes in preloads and clearance in bearing and joints. Output-only Modal Analysis assumes a complete excitation of the structure by white noise characteristics. There are several mechanisms in a machine tool under process conditions that could cause a vibration response. Besides the cutting process itself, the movement of the NC-axes, as well as rotating fans of the control system and auxiliary units, can be excitation sources. This paper investigates to what extent several excitation mechanisms in machine tools fulfill the analysis assumption and in which way the identified modal parameters depend on the boundary conditions of the excitation characteristics. [ABSTRACT FROM AUTHOR]

In contrast to other cutting processes, adiabatic blanking typically features high blanking velocities (>3 m/s), which can lead to the formation of adiabatic shear bands in the blanking surface. The produced surfaces have excellent properties, such as high hardness, low roll-over, and low roughness. However, details about the qualitative and quantitative influence of significant process parameters on the quality of the blanked surface are still lacking. In the presented study, a variable tool is used for a systematic investigation of different process parameters and their influences on the blanked surface of a hardened 22MnB5 steel. Different relative clearances (1.67% to 16.67%), velocities (7 to 12.5 m/s), and impact energies (250 J to 1000 J) were studied in detail. It is demonstrated that a relative clearance of ≤6.67% and an impact velocity of ≥7 m/s lead to adiabatic shear band formation, regardless of the impact energy. Further, an initiated shear band results in the formation of an S-shaped surface. Unexpectedly, a low impact energy results in the highest geometric accuracy. The influence of the clearance, the velocity, and the impact energy on the evolution of adiabatic shear band formation is shown for the first time. The gained knowledge can enable a functionalization of the blanked surfaces in the future [ABSTRACT FROM AUTHOR]

Many nations responded to the corona virus disease‐2019 (COVID‐19) pandemic by restricting travel and other activities during 2020, resulting in temporarily reduced emissions of CO2, other greenhouse gases and ozone and aerosol precursors. We present the initial results from a coordinated Intercomparison, CovidMIP, of Earth system model simulations which assess the impact on climate of these emissions reductions. 12 models performed multiple initial‐condition ensembles to produce over 300 simulations spanning both initial condition and model structural uncertainty. We find model consensus on reduced aerosol amounts (particularly over southern and eastern Asia) and associated increases in surface shortwave radiation levels. However, any impact on near‐surface temperature or rainfall during 2020–2024 is extremely small and is not detectable in this initial analysis. Regional analyses on a finer scale, and closer attention to extremes (especially linked to changes in atmospheric composition and air quality) are required to test the impact of COVID‐19‐related emission reductions on near‐term climate. Plain Language Summary: Many nations responded to the COVID‐19 pandemic by restricting travel and other activities during 2020. This caused a temporary reduction in emissions of CO2 and other pollutants. We compare results from twelve Earth system models to see if the emissions reductions affected climate. These twelve models performed over 300 experiments using multiple initial‐conditions. We find a consensus that aerosol amounts were reduced, especially over southern and eastern Asia, during 2020‐2024. This led to increases in solar radiation reaching the surface in this region. However, we could not detect any associated impact on temperature or rainfall. We recommend more analyses on regional scales. We also suggest that analysis of extreme weather and air quality would be useful to test the impact on climate of emission reductions due to COVID‐19. Key Points: Lockdown restrictions during COVID‐19 have reduced emissions of aerosols and greenhouse gases12 CMIP6 Earth system models have performed coordinated experiments to assess the impact of this on climateAerosol amounts are reduced over southern and eastern Asia but there is no detectable change in annually averaged temperature or precipitation [ABSTRACT FROM AUTHOR]

Motivated by the wide range of projections of regional rainfall (or precipitation, pr) based on the CMIP5 ensemble of global climate models, we investigate the atmospheric moisture budget of idealized rising‐CO2 (1pctCO2) simulations from 10 models submitted to CMIP6. We use the new CMIP6 standard variables, the vertically integrated eastward and northward moisture flux, and provide a multi‐model assessment of these, their convergence (conv), along with water vapour path (prw). Seasonal climatologies of a 20‐year base climate for pr, prw, flux, and conv match well those from the ECMWF's Reanalysis 5. In addition, composites 'H' of quantities for months in the top decile of monthly rainfall, calculated at each model grid point, produce a field of heavy rainfall, on average double that of the mean. Spatial correlation coefficients (r) between the pr and conv fields are typically.7 in each season. This rises to.9 for the corresponding H fields, due to the important link between moisture convergence and heavy rainfall. Fields of standardized change (Δ), or change per degree of global warming, were calculated. The ensemble‐mean Δpr is only weakly correlated with the base climate pr, and likewise for conv. However, the prw change is highly correlated with the base prw, pointing to the importance of the "thermodynamic" change in that variable. Globally, the net Δconv is highly correlated with Δpr, around.9. This rises to.95 for the heavy‐rain composites. Relationships between changes in pr and other components hold at grid points also, when the individual model results are correlated. Clearly, there is a dependence in the change in pr with that in conv, particularly for heavy rainfall. Assessment of a larger ensemble from CMIP6, using the new flux variables, would improve the evaluation of these processes, and potentially allow more confident projections in future rainfall changes. [ABSTRACT FROM AUTHOR]

This paper compares conventional and cryogenic cooling in the deep hole drilling of carbon fiber reinforced polymer (CFRP)/Ti stacks. Various parameters are taken into account to find if the use of cryogenic coolant is justified by the improvement of the final results. Both the thrust and the torque were acquired continuously during the machining operations and compared both in average and distribution. The use of a cryogenic coolant brings a reduction in thrust force and torque without any sensible drawback. Overall the results prove that cryogenic drilling is a suitable technology for CFRP/Ti stack drill. [ABSTRACT FROM AUTHOR]

The manufacturing process of turn-milling offers high productivity, high geometrical flexibility, safe chip breaking and machining of twist-free surfaces. However, the achievable accuracies and surface qualities do not allow the substitution of finish grinding processes. Thereby the dynamic profile of process forces is one of the main disturbance values. This paper presents a new process model of orthogonal eccentric turn-milling without axial feed. Thus the focus lies on the analysis of the process forces and their dynamic behavior caused by the changing chip cross section area on the face cutting edge. The developed model considers single and multiple cutting edge tools and has a geometrical-empirical character. This model describes the process kinematics and the error inducing process forces in orthogonal turn-milling. Their dynamic profile can be analyzed and minimized using multiple cutting edge tools and customized pre-machining of the workpiece surface topography with the goal of creating a robust process to substitute the finish grinding process in high precision applications. Such applications include, for example, the main and pin bearing seats of crank shafts used in the automotive and truck industry or even for large ship engines. The key feature is to minimize the form deviation of the cylindricity, which results from straightness and roundness of the workpiece surface to below 10 µm for crank shafts used in the truck industry. The model is adjusted and verified by experimental tests. [ABSTRACT FROM AUTHOR]

The Community Atmosphere Biosphere Land Exchange (CABLE) model has been coupled to the UK Met Office Unified Model (UM) within the existing framework of the Australian Community Climate and Earth System Simulator (ACCESS), replacing the Met Office Surface Exchange Scheme (MOSES). Here we investigate how features of the CABLE model impact on present-day surface climate using ACCESS atmosphere-only simulations. The main differences attributed to CABLE include a warmer winter and a cooler summer in the Northern Hemisphere (NH), earlier NH spring runoff from snowmelt, and smaller seasonal and diurnal temperature ranges. The cooler NH summer temperatures in canopy-covered regions are more consistent with observations and are attributed to two factors. Firstly, CABLE accounts for aerodynamic and radiative interactions between the canopy and the ground below; this placement of the canopy above the ground eliminates the need for a separate bare ground tile in canopy-covered areas. Secondly, CABLE simulates larger evapotranspiration fluxes and a slightly larger daytime cloud cover fraction. Warmer NH winter temperatures result from the parameterization of cold climate processes in CABLE in snow-covered areas. In particular, prognostic snow density increases through the winter and lowers the diurnally resolved snow albedo; variable snow thermal conductivity prevents early winter heat loss but allows more heat to enter the ground as the snow season progresses; liquid precipitation freezing within the snowpack delays the building of the snowpack in autumn and accelerates snow melting in spring. Overall we find that the ACCESS simulation of surface air temperature benefits from the specific representation of the turbulent transport within and just above the canopy in the roughness sublayer as well as the more complex snow scheme in CABLE relative to MOSES. [ABSTRACT FROM AUTHOR]

The Community Atmosphere Biosphere Land Exchange (CABLE) model has been coupled to the UK Met Office Unified Model (UM) within the existing framework of the Australian Community Climate and Earth System Simulator (ACCESS), replacing the Met Office Surface Exchange Scheme (MOSES). Here we investigate how features of the CABLE model impact on present day surface climate using ACCESS atmosphere-only simulations. The main differences attributed to CABLE include a warmer winter and a cooler summer in the Northern Hemisphere (NH), earlier NH spring runoff from snowmelt, and smaller seasonal and diurnal temperature ranges. Cooler NH summer temperatures in canopy covered areas are attributed to two factors. Firstly CABLE accounts for aerodynamic and radiative interactions between the canopy and the ground below; this placement of canopy above the ground eliminates the need for a separate bare ground tile in canopy covered areas. Secondly, CABLE produces larger evapotranspiration fluxes and slightly larger daytime cloud cover fraction. Warmer NH winter temperatures result from the parameterization of cold climate processes in CABLE in snow covered areas. In particular prognostic snow density increases through the winter and lowers diurnally resolved snow albedo; variable snow thermal conductivity prevents early winter heat loss but allows more heat to enter the ground as the snow season progresses; liquid precipitation freezing within the snowpack delays the building of the snow pack in autumn and accelerates snow melting in spring. [ABSTRACT FROM AUTHOR]

The article presents a study that evaluates the simulation of mean climate and El Niño Southern Oscillation (ENSO)-related rainfall variability in Australia. It investigated using Mark 3.6 (Mk3.6) which is the new version of Commonwealth Scientific and Industrial Research Organization (CSIRO). It indicates that Mk3.6 shows several improvements on the simulation. It concludes that the interactive dust in Mk3.6 has a possible mechanism for the improved simulation of rainfall variability.

The paper presents research on increasing the efficiency of industrial centrifugal fans, which are the third highest energy-consuming group of devices. This problem is related to the frequent incompatibility of the fan characteristics with the flow conditions of the installation in which they are operated, which lowers efficiency and increases energy consumption. By ensuring high efficiency of these devices, it is possible to significantly reduce the operating costs of such industrial equipment. For this purpose, a unique concept of regulating the flow parameters of centrifugal fans was developed. The scientific basis of this idea is that a relatively small change in the impeller diameter of the fan significantly affects the flow rate and the pressure rise of the fan. Therefore, the idea uses variable length of the impeller blades by dividing them into a fixed and a movable part. It enables adjustment of the length of the blades, which allows extension of the range of effective and efficient operating parameters. On this basis, several technical solutions of the regulation system were developed, which were then tested using simulation and analytical methods. Two material options for the moving part of the blade have also been developed, one made of metallic materials (high-strength steel and aluminum) and the other made of composite materials. The research showed a significant influence of the mass of the movable part of the blade on the load of the control system. Therefore, ultra-light material variants were used for the impeller blades. The flow simulation tests of the new method of adjusting the fan flow parameters confirmed the effectiveness of this solution. As a result, a wider range of highly efficient centrifugal fans equipped with such a control system was obtained. [ABSTRACT FROM AUTHOR]

Since 1950, there has been an increase in rainfall over North West Australia (NWA), occurring mainly during the Southern Hemisphere (SH) summer season. A recent study using twentieth-century multimember ensemble simulations in a global climate model forced with and without increasing anthropogenic aerosols suggests that the rainfall increase is attributable to increasing Northern Hemisphere aerosols. The present study investigates the dynamics of the observed trend toward increased rainfall and compares the observed trend with that generated in the model forced with increasing aerosols. It is found that the observed positive trend in rainfall is projected onto two modes of variability. The first mode is associated with an anomalously low mean sea level pressure (MSLP) off NWA instigated by the enhanced sea surface temperature (SST) gradients toward the coast. The associated cyclonic flows bring high-moisture air to northern Australia, leading to an increase in rainfall. The second mode is associated with an anomalously high MSLP over much of the Australian continent; the anticyclonic circulation pattern, over northern Australia, determines that when rainfall is anomalously high, west of 130°E, rainfall is anomalously low east of this longitude. The sum of the upward trends in these two modes compares well to the observed increasing trend pattern. The modeled rainfall trend, however, is generated by a different process. The model suffers from an equatorial cold-tongue bias: the tongue of anomalies associated with El Niño–Southern Oscillation extends too far west into the eastern Indian Ocean. Consequently, there is an unrealistic relationship in the SH summer between Australian rainfall and eastern Indian Ocean SST: the rise in SST is associated with increasing rainfall over NWA. In the presence of increasing aerosols, a significant SST increase occurs in the eastern tropical Indian Ocean. As a result, the modeled rainfall increase in the presence of aerosol forcing is accounted for by these unrealistic relationships. It is not clear whether, in a model without such defects, the observed trend can be generated by increasing aerosols. Thus, the impact of aerosols on Australian rainfall remains an open question. [ABSTRACT FROM AUTHOR]

Presents a study which investigated the effects of closure-based eddy diffusion on the climate and spectra of atmospheric global climate model (GCM). Information on closure-based eddy viscosity; Details of GCM simulations with standard diffusion; Description of GSM simulations with net eddy viscosity parameterization.

Presents a study on systematic kinectic energy errors. Levels energy errors are examined by; Behavior of kinectic energy spectra.

In the next few years there is likely to be a large growth of interest in the dynamic modelling of travel behaviour. In order to try to avoid the eventual collapse of enthusiasm which has sometimes occurred with other new developments when they turn out not to provide transport planning with the hoped-for panacea, this paper aims to demonstrate the diversity of approaches which will be required to tackle the subject of dynamics. In particular, it identifies three overlapping but distinct levels at which dynamics interact with travel behaviour - microdynamics, which is concerned with the detailed scheduling of activities and travel within a day - macrodynamic modifiers, whereby changes in medium- and long-term behaviour which are often considered to be instantaneous are in fact subject to important phasing considerations - and macrodynamic processes, which deal with the overriding demographic processes of birth, ageing and death. The paper suggests approaches to the incorporation of these three topics into the forecasting of travel behaviour. [ABSTRACT FROM AUTHOR]

In recent years, due to changing the human lifestyle, the number of sport trainers has been increased. The conventional classifiers as Naive Bayes (NB), Decision Trees (DT) and Convolutional Neural Networks (CNNs) can be used in this domain to recognize and count sports activities of subjects and provide them qualified feedback. This paper uses literature studies and selected sport activities, namely squats, pull-ups and dips as the dataset based on three UWB sensors with additional inertial data, which contains the reduced data set consisting of 17 training sets and next for CNN training the 1444 samples describing exercises and 2024 samples with breaks, which were grouped in the ratio 70:15:15. The recognition accuracy of the NB and DT were 89.4 and 92.9 accordingly. Next, the extensive performance analysis of the CNN based on experiments for different kernel sizes, different number of filters for single and dual layer networks was carried out. Moreover, the innovative model for sport activities recognition in the form the combination of several networks forming Ensemble Neural Network (ENN) was created. The accuracy was at the level 94.81 of CNN and exceeded 95% of ENN. The proposed prototype of the measurement system and data acquisition platform for sport activities recognition was highlighted as the great potential in the privacy-training sport system. [Display omitted] • The approachto the measurement system for sport activities: squats, pull-ups and dipsrecognition was developed. • The developedmodel for sport activities recognition using Ensemble Neural Network (ENN)was created. • The testingaccuracy in sport activity recognition exceeded 95%. • The great potential in the privacy-training of theproposed system was highlighted. [ABSTRACT FROM AUTHOR]