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The evolution of the lunar magnetic field can reveal the Moon's interior structure, thermal history, and surface environment. The mid-to-late-stage evolution of the lunar magnetic field is poorly constrained, and thus, the existence of a long-lived lunar dynamo remains controversial. The Chang'e-5 mission returned the heretofore youngest mare basalts from Oceanus Procellarum uniquely positioned at midlatitude. We recovered weak paleointensities of ~2 to 4 microtesla from the Chang'e-5 basalt clasts at 2 billion years ago, attesting to the longevity of the lunar dynamo until at least the Moon's midstage. This paleomagnetic result implies the existence of thermal convection in the lunar deep interior at the lunar midstage, which may have supplied mantle heat flux for young volcanism. [ABSTRACT FROM AUTHOR]

Harvesting the energy from the interaction between hygroscopic materials and atmospheric water can generate green and clean energy. However, the ion diffusion process of moisture-induced dissociation leads to the disappearance of the ion concentration gradient gradually, and there is still a lack of moisture-based power generation devices with truly continuous operation, especially the duration of the current output still needs to be extended. Here, we propose a design for reconstructing the ion concentration gradient by coupling photocatalytic hydrogen evolution reaction with hydrovoltaic effect, to report a moisture-enabled electric generator (MEG) with continuous current output. We show that the introduction of the photocatalytic layer not only absorbs light energy to greatly increase the power generation of the MEG (500% power density enhancement), but more importantly, the photocatalytic hydrogen evolution process consumes the pre-stacked ions to restore the ion concentration gradient, allowing the MEG to continuously output current for more than 600 hours, which is 1 to 2 orders of magnitude higher than the great majority of existed MEGs in terms of the current output duration. This study designs a moisture-enabled electric generator (MEG) with a photocatalytic layer, achieving a 500% power density enhancement and continuous current output for over 600 hours, addressing the challenge of extended operation duration [ABSTRACT FROM AUTHOR]

The cause of the asymmetry in the sunspot distribution in the northern and southern hemispheres of the Sun at the end of the Maunder Minimum is studied. It is demonstrated that the expected asymmetry of generation sources is insufficient for such an explanation. To study the influence of asymmetry of generation sources, numerical simulation is used, based on modifications to the Parker model. [ABSTRACT FROM AUTHOR]

The characteristics of solar cycles important for the development of dynamo theory can manifest themselves differently when different activity indices are used. To study the features of the north–south (N–S) asymmetry of solar activity, a comparison was made of the time profiles of active regions (ARs) of the 23rd and 24th cycles based on data on their number (the most accessible and frequently used) and magnetic flux (allowing a more complete assessment about the generative function of the dynamo process). We used data on 3047 ARs that appeared on the disk from June 1996 to December 2020 according to the MMC ARs CrAO (magneto-morphological classification of ARs of the Crimean Astrophysical Observatory) catalog (http://sun.crao.ru/databases/catalog-mmc-ars). The attribution of AR to the classes of the regular and irregular sunspot groups was taken into account in accordance with the MMC ARs CrAO. Analysis of the results showed the following. Variations of ARs of both MMC classes are associated with a cycle, which confirms their relationship with the action of the global dynamo. Due to the overlap of multipeak ARs profiles of different classes, a classic double-peak cycle structure is formed in the two hemispheres. Variations in the relative position of profiles for the number and magnetic flux of ARs (for groups of each class in each hemisphere) during the cycle can be associated with changes in the sizes of ARs. This makes it possible to suggest the multicomponent nature of the dynamo process, which consists in joint manifestation of global (responsible for the production of ARs) and turbulent (associated with the fragmentation of magnetic structures due to turbulence in the convection zone) components of the dynamo. The strongest magnetic fluxes observed for the irregular groups in the maximum of the cycle may also indicate action of the turbulent component of the dynamo distorting the regular flux tube. The pronounced N–S asymmetry of these fluxes agrees with the hypothesis on the possibility of weakening of the toroidal field in one of the hemispheres due to the interaction of the dipole and quadrupole components. [ABSTRACT FROM AUTHOR]

Many giant stars are magnetically active, which causes rotational variability, chromospheric emission lines, and X-ray emission. Large outbursts in these emission features can set limits on the magnetic field strength and thus constrain the mechanism of the underlying dynamo. HD 251108 is a Li-rich active K-type giant. We find a rotational period of 21.3 days with color changes and additional long-term photometric variability. Both can be explained with very stable stellar spots. We followed the decay phase of a superflare for 28 days with NICER and from the ground. We track the flare decay in unprecedented detail in several coronal temperature components. With a peak flux around 1034 erg s−1 (0.5–4.0 keV) and an exponential decay time of 2.2 days in the early decay phase, this is one of the strongest flares ever observed, yet it follows trends established from samples of smaller flares, for example, for the relations between H α and X-ray flux, indicating that the physical process that powers the flare emission is consistent over a large range of flare energies. We estimate a flare loop length about 2–4 times the stellar radius. No evidence is seen for abundance changes during the flare. [ABSTRACT FROM AUTHOR]

The work is dedicated to the analysis of the efficiency of utilization of low-potential heat of the hydrogen complex at the NPP power unit. A new scheme for the integration of hydrogen technologies into an existing energy facility has been developed with an assessment of the economic efficiency of the event. It is shown that due to the utilization of low-potential heat obtained during the production of hydrogen by electrolysis, it is possible to increase the available capacity of nuclear power plants, which will ensure an increase in hydrogen production while reducing the cost. The object of integration, the Kola NPP, was selected and justified. Simulation modeling of the thermal circuit of a nuclear power plant power unit with a K-220-44 turbine unit in the United Cycle CAD, modeling of the hydrogen electrolysis process in the Aspen HYSYS program, with determination of the potential of waste heat in a hydrogen generating plant, as well as mathematical modeling using probabilistic estimation techniques to determine the main parameters of the economic efficiency of implementation, were chosen as research methods events. The paper estulates the theoretical possible volume of hydrogen generation at the Kola NPP, which amounted to 6.46 × 108 m3/year. An increase in power by 6.24 MW at the terminals of electric generators is shown due to the utilization of thermal energy of low potential electrolysis plants for two power units of the station. An assessment of the economic efficiency of the introduction of a heat recovery unit into the production cycle of a nuclear power plant has been carried out. An increase in the theoretical possible volume of hydrogen generation by 3 × 104 m3/day was obtained, which gives the expected annual economic effect from the introduction of the technology of 1.95 × 104 $/year. [ABSTRACT FROM AUTHOR]

Magnetic materials play a crucial role in our everyday lives. As permanent magnets, they are core components in electric motors such as generators for wind turbines, or, as magnetocaloric magnets, they have the potential to change the cooling technology of tomorrow. All of this makes these materials key contributors to "green" energy conversion technology. Accordingly, pushing the development of these materials with a special focus on the performance, efficiency, and harmlessness of the material components contained for humans and the environment is of crucial importance. This work deals with the finite element‐based simulations within the framework of the micromagnetic theory to numerically support the quest of characterizing novel magnetic materials. The main focus remains on the numerical modeling of permanent magnetic polycrystalline materials and the influence of grain boundaries on the effective magnetization. For this purpose, large‐scale simulations of permanent magnetic neodymium‐iron‐boron (Nd2Fe14B$\text{Nd}_2\text{Fe}_{14}\text{B}$) samples are carried out and the influence of different mesh sizes on the effective magnetization behavior is investigated. [ABSTRACT FROM AUTHOR]

Due to the increasing variety of converters in more electric aircraft (MEA), the stability of the MEA power system has become a critical issue that receives wide concerns. As the primary power source for MEA, the wound rotor synchronous machine (WRSM) greatly affects the stability of the whole power system, and therefore accurate modelling of the WRSM serves as the basis for the analysis of system characteristics and even stability. Nevertheless, the complex structure and coupling of WRSM bring great challenges to small‐signal modelling methods. This paper introduces a novel method to model the WRSM in a modular and cascaded manner. Instead of deriving the complex transfer function, the proposed method uses a dual port to model each component. By connecting the dual port of each component from the rear stage to the front stage in a cascaded way, a dual‐port network can be built to describe the external impedance characteristics of the WRSM. Kirchhoff law can be applied to calculate the impedance by circumventing the complicated decoupling process. The proposed dual‐port network model has been validated on a hardware‐in‐loop platform. Furthermore, the output impedance characteristics of the AC port has also been analysed with the proposed model. [ABSTRACT FROM AUTHOR]

Attempts have been made repeatedly to investigate the effect of the geomagnetic activity on the equatorial plasma bubble (EPB) generation. At the moment, it is generally accepted that the geomagnetic activity tends to suppress the EPB generation and evolution in the pre-midnight sector. As for the post-midnight sector, it is believed that the EPB occurrence probability will increase after midnight as the geomagnetic activity increases. Moreover, the growth rates of the EPB occurrence probability will strongly depend on the solar activity: at the solar activity minimum, they will be the most significant. A sufficient amount of the observations is required to confirm these ideas. For this purpose, the EPB observations obtained on board the ISS-b satellite (~972–1220 km, 1978–1979) in the pre- and post-midnight sectors are best suited. The data were considered in two latitudinal regions: the equatorial/low-latitude (±20°) and mid-latitude ±(20°–52°) regions. The LT- and Kp-variations of the EPB occurrence probability were calculated for both groups. (1) It was revealed that the occurrence probability maximum of the EPBs recorded at the equator and low latitudes is observed in the premidnight sector. The EPB occurrence probability decreases with increasing the Kp-index with a delay of 3 and 9 h before the EPB detection. (2) However, the occurrence probability maximum of the EPBs recorded at the mid-latitudes occurs in the post-midnight sector. Their occurrence probability increases slightly with the increase of the Kp-index taken 9 h before the EPB detection. Thus, the idea of the ionospheric disturbance dynamo (IDD) influence on the post-midnight EPB generation has been confirmed. The IDD mechanism "switched on" after some hours of the enhanced geomagnetic activity and favors the generation. However, its influence is weakened during the years of increased solar activity. [ABSTRACT FROM AUTHOR]

We compute the exact relaxation and \Lambda-convex hull of the kinematic dynamo equations and show that they coincide. We also find the relaxation in the stationary case and present applications to the infinite-time limit in the kinematic dynamo problem. [ABSTRACT FROM AUTHOR]

Owing to the high cost of installation and operation, distributed flexible AC transmission system (FACTS) technology gives opportunity to provide costeffective solution in power system operation and control. A distributed static series compensator (DSSC) is a series FACTS device and it is placed equidistantly placed on the existing line to vary the line current. Active power can be controlled in the line with the help of DSSC. This paper presents DSSC for active power flow control to enhance system loadability index and to minimize reactive power generation by generators. Since DSSC is of low power. a small value of reactance is emulated in the line. Large number of DSSC's are distributed along the transmission line at regular intervals to realize considerable change in the current. A particle swarm optimization is implemented to determine DSSC's emulated reactance optimally. In this condition, all the lines flowing power in their limits with increased loading condition. Maximum system loadability index is evaluated by employing optimal number of DSSC's on the line. A multiobjective problem is formulated. One objective function is formed such that no line would become overloaded even when loading is increased. Other objective is formulated to minimize reactive power generation by generators. A compromise solution is investigated for optimally connected of DSSC devices to achieve both the objective functions. IEEE 14 bus system is taken for MATLAB simulation of DSSC compensated system. [ABSTRACT FROM AUTHOR]

Abstract The large scale deployment of modern wind turbines and the yearly increase of installed capacity have drawn attention to their operation and maintenance issues. The development of highly reliable and low‐maintenance wind turbines is an urgent demand in order to achieve the low‐carbon goals, and the arrival of fault diagnosis provides assurance for its satisfactory operation and maintenance. Numerous statistical studies have pointed out that generator failures are a main cause of wind turbine system downtime. The generator, as one of the core components, converts rotating mechanical energy into electrical energy. However, the generators can hardly operate reliably towards the end of the turbine life owing to the variable‐speed conditions and harsh electromagnetic environments. This article first provides a comprehensive and up‐to‐date review of the electrical and mechanical failures of various parts (stator, rotor, air gap and bearings) of the generator. Then the fault characteristics and diagnostic processes of generators are investigated, and the principles and processes of fault diagnosis are discussed. Finally, the application of four categories of model‐based, signal‐based, knowledge‐based and hybrid approaches to wind turbine generator fault diagnosis is summarized. The comprehensive review shows that the hybrid approach is now the leading and most accurate tool for real‐time fault diagnosis for wind turbine generators. A qualitative and quantitative assessment of algorithm performance using false alarm rates is proposed. The methodology can subsequently be applied to the wind industry.

Abstract This article presents an analytical design approach for the inner and outer rotor Permanent Magnet Synchronous Generators (PMSGs) that are a key component of wind turbines. By developing the analytical model, sensitivity analysis has been performed to determine the effect of some important geometrical and electromagnetic parameters on the generator's output characteristics. The GA optimization algorithm was used to find optimized designs in terms of efficiency, weight, cost, and temperature rise. In order to find the global optimization solution within the allowed variable range and in accordance with the constraints, a combined objective function has also been defined. In order to validate the analytical model, ANSYS electromagnetic and thermal simulations have been used. With this approach, the designer is provided with a good understanding of the input parameters and constraints in light of the application requirements.

Abstract This paper investigates the benefits and challenges of the multi‐MW direct‐drive offshore wind Vernier generators. It is worth noting that the comparison of generator topologies presented in ref. [1] was for the same power level and therefore a reduced machine volume for the surface‐mounted permanent magnet Vernier (SPM‐V) generators. This would mainly impact the capital expenditure (CAPEX) cost between the different investigated machines. Whereas in this paper, the performance is compared for the same machine volume that allows the Vernier generators to produce a much higher energy yield than a conventional SPM generator. As the extra energy yield would be beneficial over the lifetime of the turbine, this will have a bigger impact than the CAPEX cost savings with a reduced machine volume. In addition, a novel Vernier machine with magnets on both the stator and rotor has been proposed to further improve the energy yield. In addition to the basic electromagnetic performance, the levelised cost of energy (LCOE) of the three generator topologies, that is, the conventional SPM, SPM‐V and the proposed Vernier machines, has been compared. The direct‐drive powertrain systems with SPM‐V and the proposed Vernier generators can achieve LCOE of 12.3% and 24% lower than that of the conventional SPM generators, indicating their huge potential as an alternative to reduce the overall cost of energy.

Ganymede is the only known moon with an active dynamo. No mission has discovered intrinsic magnetism at the other Galilean satellites: Io, Europa, and Callisto. A dynamo requires a large magnetic Reynolds number, which in turn demands, for these moons, a large metallic core that is cooling fast enough for convection. Here we quantify these requirements to construct a regime diagram for the Galilean satellites. We compute the internal heat fluxes that would sustain a dynamo over the wide ranges of plausible radii for their metallic cores. Below a critical radius, no plausible heat flux will sustain a dynamo. Europa likely sits on the opposite side of this limit than Ganymede and Io. We predict that future missions may confirm a small (or absent) core, meaning that Europa could not sustain a dynamo even if its interior were cooling as quickly as Ganymede's core. Plain Language Summary: In the late 1990s, the NASA Galileo spacecraft visited the four largest moons of Jupiter: Io, Europa, Ganymede, and Callisto. Many studies interpret the Galileo gravity and magnetic field data to mean that: (a) Ganymede's intrinsic magnetic field arises from convection in a liquid metal core (i.e., a "dynamo" that converts mechanical energy into electromagnetic energy), (b) Europa has a metal core that is somehow incapable of generating a detectable magnetic field, and (c) Callisto may not have a metal core at all. Indeed, Ganymede is the only moon in our solar system known to sustain an active dynamo. Confirming the presence (or absence) of core convection provides us with valuable insight into the moons' structural and thermal history. In this study, we show that Europa's and Callisto's metal core (if they exist) may be too small to produce a dynamo, even if they convect. Crucially, no celestial body is known to have a convecting metal core without sustaining a dynamo too, but Europa might be an exception. Recently launched missions such as NASA's Europa Clipper and ESA's JUICE may test whether a small core size can explain the absence of dynamos at Europa and Callisto. Key Points: Dynamos in the Galilean moons would require both a dynamo‐producing region thicker than ∼250 km and core heat fluxes above ∼3 mW m−2Ganymede and Io probably have larger metallic cores than Europa and Callisto, but all satellites likely have similar core compositionsA small core could explain the absence of a strong dynamo at Europa even if Europa and Ganymede have similar core heat fluxes [ABSTRACT FROM AUTHOR]

Moisture-driven electricity generators (MEGs) have been extensively researched; however, high-performance flexible variants have seldom been demonstrated. Here we present a novel complex coacervation with built-in potential strategy for developing a high-performance uniaxial MEG, featuring a core of poly(3,4-ethylenedioxythiophene) (PEDOT) with a built-in charge potential and a gel shell composed of poly(diallyldimethylammonium chloride) (PDDA) and sodium alginate (NaAlg) coacervate. The complex coacervation of two oppositely charged polyelectrolytes produces extra mobile carriers and free volume in the device; meanwhile, the PEDOT core's surface charge significantly accelerates carrier diffusion. Consequently, the uniaxial fiber-based MEG demonstrates breakthrough performance, achieving an output voltage of up to 0.8 V, a maximum current density of 1.05 mA/cm2, and a power density of 184 μW/cm2 at 20% relative humidity. Moreover, the mechanical robustness is ensured for the PEDOT nanoribbon substrate without performance degradation even after 100,000 folding cycles, making it suitable for self-powered human interactive sensor and synapse. Notably, we have constructed the inaugural MEG-synapse self-powered device, with a fiber-based MEG successfully operating a synaptic memristor, thereby emulating autonomous human synapses linked with fibrous neurons. Overall, this work pioneers innovative design strategies and application scenarios for high-performance MEGs. The authors present a core–shell fiber moisture-driven electric generator by a synergetic complex coacervation and built-in potential strategy, enabling self-powered human interactive sensors and synaptic devices. [ABSTRACT FROM AUTHOR]

Ubiquitous moisture is of particular interest for sustainable power generation and self‐powered electronics. However, current moisture electric generators (MEGs) can only harvest moisture energy in the air, which tremendously limits the energy harvesting efficiency and practical application scenarios. Herein, the operationality of MEG from air to underwater environment, through a sandwiched engineered‐hydrogel device with an additional waterproof breathable membrane layer allowing water vapor exchange while preventing liquid water penetration, is expanded. Underwater environment, the device can spontaneously deliver a voltage of 0.55 V and a current density of 130 µA cm−2 due to the efficient ion separation assisted by negative ions confinement in hydrogel networks. The output can be maintained even under harsh underwater environment with 10% salt concentration, 1 m s−1 disturbing flow, as well as >40 kPa hydraulic pressure. The engineered hydrogel used for MEG also exhibits excellent self‐healing ability, flexibility, and biocompatibility. As the first demonstration of practical applications in self‐powered underwater electronics, the MEG device is successfully powering a wireless emitter for remote communication in water. This new type of MEG offers an innovative route for harvesting moisture energy underwater and holds promise in the creation of a new range of innovative electronic devices for marine Internet‐of‐Things. [ABSTRACT FROM AUTHOR]

Data from the Michelson Doppler Imager (MDI) and Helioseismic and Magnetic Imager (HMI) are analyzed from 1996 to 2023 to investigate tilt angles (γ) of bipolar magnetic regions and Joy's law for Solar Cycles 23 and 24 and a portion of Cycle 25. The HMI radial magnetic field (B r ) and MDI magnetogram (B los) data are used to calculate (γ) using the flux-weighted centroids of the positive and negative polarities. Each active region (AR) is only sampled once. The analysis includes only Beta (β)-class ARs since computing γ of complex ARs is less meaningful. During the emergence of the ARs, we find that the average tilt angle ( γ ¯ ) increases from 3.°30 ± 0.75 when 20% of the flux has emerged to 6.°79° ± 0.66 when the ARs are at their maximum flux. Cycle 24 has a larger average tilt, γ ¯ 24 =6.67 ± 0.66, than Cycle 23, γ ¯ 23 = 5.11 ± 0.61. No significant difference is found in the slope of Joy's law or γ ¯ when sampling the ARs at the time of maximum flux or central meridian crossing. There are persistent differences in γ ¯ in the hemispheres, with the Sun's southern hemisphere having higher γ ¯ in Cycles 23 and 24, but the uncertainties are such that these differences are not statistically significant. [ABSTRACT FROM AUTHOR]

We present an analytic, quasi-local model for accretion discs threaded by net, vertical magnetic flux. In a simple slab geometry and ignoring stochastic mean-field dynamo effects, we calculate the large-scale field resulting from the balance between kinematic field amplification and turbulent diffusion. The ability of the disc to accumulate magnetic flux is sensitive to a single parameter dependent on the ratio of the vertical diffusion time to the Alfvén crossing time, and we show how the saturation levels of magnetorotational and other instabilities can govern disc structure and evolution. Under wide-ranging conditions, inflow is governed by large-scale magnetic stresses rather than internal viscous stress. We present models of such 'magnetically boosted' discs and show that they lack a radiation pressure-dominated zone. Our model can account for 'magnetically elevated' discs as well as instances of midplane outflow and field reversals with height that have been seen in some global simulations. Using the time-dependent features of our model, we find that the incorporation of global transport effects into disc structure can lead to steady or episodic 'magnetically arrested discs' that maximize the concentration of magnetic flux in their central regions. [ABSTRACT FROM AUTHOR]

A vortex generator was installed inside an electric agglomeration device to apply aerodynamic agglomeration in the same space as electric agglomeration. Computational fluid dynamics simulation was utilized to assess the combined effects of electric and aerodynamic agglomeration, and this was subsequently validated through experiments. The discrete phase model was used to track particle trajectories. The results showed that both the aerodynamic agglomeration through the vortex generator and the electric agglomeration through the electric field were effective. When these two agglomerations existed individually in series, the total removal efficiency for submicron particles was 32.5%. However, when they coexisted in the same space, the efficiency increased to 50%. This increase is attributed to the increase in residence time when the vortex generator was added to a space with an electric field. This led to particles being exposed to the electric field for a longer duration, thus generating a synergistic effect. [ABSTRACT FROM AUTHOR]

The large scale deployment of modern wind turbines and the yearly increase of installed capacity have drawn attention to their operation and maintenance issues. The development of highly reliable and low‐maintenance wind turbines is an urgent demand in order to achieve the low‐carbon goals, and the arrival of fault diagnosis provides assurance for its satisfactory operation and maintenance. Numerous statistical studies have pointed out that generator failures are a main cause of wind turbine system downtime. The generator, as one of the core components, converts rotating mechanical energy into electrical energy. However, the generators can hardly operate reliably towards the end of the turbine life owing to the variable‐speed conditions and harsh electromagnetic environments. This article first provides a comprehensive and up‐to‐date review of the electrical and mechanical failures of various parts (stator, rotor, air gap and bearings) of the generator. Then the fault characteristics and diagnostic processes of generators are investigated, and the principles and processes of fault diagnosis are discussed. Finally, the application of four categories of model‐based, signal‐based, knowledge‐based and hybrid approaches to wind turbine generator fault diagnosis is summarized. The comprehensive review shows that the hybrid approach is now the leading and most accurate tool for real‐time fault diagnosis for wind turbine generators. A qualitative and quantitative assessment of algorithm performance using false alarm rates is proposed. The methodology can subsequently be applied to the wind industry. [ABSTRACT FROM AUTHOR]

When navigating in ice zones, broken ice can be drawn into the propeller by the wake current, significantly altering the propeller load and causing severe fluctuations in the power grid of electrical propulsion ship. To address this issue, this paper presents two kinds of power redistribution control (PRC) strategies, which utilises the dynamic feedback from the ship's generator sets to the electric propulsion system to improve the frequency control. The PRC strategy #2, which receives feedback from generator's torque deviation, has better control effect than PRC strategy #1 with feedback from speed deviation. Since the accuracy of the estimated mechanical torque directly affects the control effect of strategy #2, this paper designs a torque observer based on the Belief Rule Base (BRB) by matching the PRC strategy to regulate the grid frequency in real-time. Given the power grid's fluctuations primarily caused by aft propellers, the power will be partly redistributed to the bow thruster to stabilise the ship's grid. Experiments show that this method can maintain the stability of the grid frequency by quickly correcting the power distribution during the process of sudden shedding propeller load. [ABSTRACT FROM AUTHOR]

Context. The long-term solar magnetic activity and its cyclical behaviour, which is maintained by a dynamo mechanism, are both still challenging problems for astrophysics. In particular, an atypical event occurred between 1645 and 1715, when the solar activity was remarkably decreased and the number of sunspots was extremely reduced. However, the exact events that unfolded during the solar cycle remain unclear. The discovery of longer activity minima in cool stars may shed light on the nature of the complex mechanisms involved in the long-term behaviour of the solar-stellar dynamo. Aims. Our aim is to explore whether the G5V solar-like star HD 4915, which showed a striking chromospheric activity pattern in a previous study performed with HIRES data, might be considered a bona fide Maunder Minimum (MM) candidate. Methods. We analysed over 380 spectra acquired between 2003 and 2022 using the HARPS and HIRES spectrographs. We carried out a detailed search for activity signatures in HD 4915 by using the Mount Wilson and the Balmer Hα activity indexes. This task was performed by means of the generalised Lomb-Scargle periodogram. Results. The new HARPS data show that the chromospheric activity of HD 4915 is not decreasing. In fact, the increases in the activity after the broad minimum in three years reaches the level of activity before this phase, suggesting that it is not entering an MM phase. We also calculate a rotation period of 23.4 ± 0.2 d, which has not been reported before. Conclusions. HD 4915 shows a distinctive activity behaviour that was initially attributed to a possible and incipient MM phase. Additional HARPS data allowed us to discard an MM in the star. Our analysis shows that the complex activity pattern of HD 4915 might be ruled by a multiple activity cycle, in which a shorter cycle of 4.8 yr is modulated by a potential longer cycle. More activity surveys with extensive records and suitable cadence are crucial for an accurate identification of stars in magnetic grand minima. [ABSTRACT FROM AUTHOR]

Context. Although the magnetic fields in the quiet Sun account for the majority of the magnetic energy in the solar photosphere, inferring their exact spatial distribution, origin, and evolution poses an important challenge because the signals lie at the limit of today's instrumental precision. This severely hinders and biases our interpretations, which are mostly made through nonlinear model-fitting approaches. Aims. Our goal is to directly compare simulated and observed polarization signals in the Fe I 6301 Å and 6302 Å spectral lines in the very quiet Sun, the so-called solar internetwork (IN). This way, we aim to constrain the mechanism responsible for the generation of the quiet Sun magnetism while avoiding the biases that plague other diagnostic methods. Methods. We used three different three-dimensional radiative magneto-hydrodynamic simulations representing different scenarios of magnetic field generation in the internetwork: small-scale dynamo, decay of active regions, and horizontal flux emergence. We synthesized Stokes profiles at different viewing angles and degraded them according to the instrumental specifications of the spectro-polarimeter (SP) on board the Hinode satellite. Finally, we statistically compared the simulated spectra to the Hinode/SOT/SP observations at the appropriate viewing angles. Results. Of the three simulations, the small-scale dynamo best reproduced the statistical properties of the observed polarization signals. This is especially prominent for the disk center viewing geometry, where the agreement is excellent. Moving toward more inclined lines of sight, the agreement worsens slightly. Conclusions The agreement between the small-scale dynamo simulation and observations at the disk center suggests that small-scale dynamo action plays an important role in the generation of quiet Sun magnetism. However, the magnetic field around 50 km above the continuum layer in this simulation does not reproduce observations as well as at the very base of the photosphere. [ABSTRACT FROM AUTHOR]

The Sun exhibits episodic surges of magnetic activity across a range of temporal and spatial scales, the most prominent of which is the 11-th year modulation of sunspot production. Beside the ∼170 (min to max) decadal variation in sunspot production there is a less-explored quasi-annual variation in the range of 25-50 sunspots/year in magnitude. In addition, there is there is a slower, ∼80 year period, 10-50 variation in the sunspot number, that is commonly referred to as the "Gleissberg Cycle." Using a suite of contemporary and historical observations we will illustrate these elements of our star's episodic behavior and present a hypothesis that may provide a consistent physical link between the observed "climatic," "decadal," and "seasonal" magnetic variation of our star. [ABSTRACT FROM AUTHOR]

In this work, a computer Simulink model of a wind power plant has been developed, which uses a magnetic gearbox instead of a mechanical gearbox and also contains a synchronous permanent magnet generator. A separate Simulink model of a magnetic gearbox built on the basis of a modulated magnetic field in the air gap was developed, which allows to study the stability of its operation both in steady-state and transient modes. Calculations of various dynamic modes of the wind power plant’s operation were carried out, based on the developed model, such as the starting mode, an instantaneous increase in the wind speed acting on the wind turbine, and an increase in the load of the electric generator. According to the results of the calculations, it is shown that in transient modes, when short-term overloads occur, both rotors of the magnetic gearbox can fall out of synchronous motion for a certain period of time and then, depending on the parameters of the gearbox (as well as its other elements), the electromechanical system either reaches a certain operating steady-state mode or loses the ability to transfer mechanical power from the wind turbine to the generator. It has been shown that the use of a more powerful magnetic gearbox, with an increased value of the maximum magnetic torque, allows of a more overload-resistant operation of both: a gearbox and the wind plant as a whole. References 9, figures 10. [ABSTRACT FROM AUTHOR]

As advanced sensors and weapons require high power, naval vessels have increasingly adopted electric propulsion systems. This study aims to enhance the efficiency and operability of electric propulsion systems over traditional mechanical propulsion systems by analyzing the operational profiles of modern naval vessels. Consequently, a battery-integrated generator-based electric propulsion system was selected. Considering the purpose of the vessel, a specification selection procedure was developed, leading to the design of a hybrid electric propulsion system (comprising one battery and four generators). The power management control technique of the proposed propulsion system sets the operating modes (depending on the specific fuel oil consumption of the generators) to minimize fuel consumption based on the operating load. Additionally, load distribution control rules for the generators were designed to reduce energy consumption based on the load and battery state of charge. MATLAB/Simulink was used to evaluate the proposed system, with simulation results demonstrating that it maintained the same propulsion performance as existing systems while achieving a 12-ton (22%) reduction in fuel consumption. This improvement results in cost savings and reduced carbon dioxide emissions. These findings suggest that an efficient load-sharing controller can be implemented for various vessels equipped with electric propulsion systems, tailored to their operational profiles. [ABSTRACT FROM AUTHOR]

The three primary markets for carbon emission reduction trading are green certificate, green power, and carbon emission right markets. This paper suggests utilizing game theory to analyze the behaviors of government and enterprises in multi-market synergistic trading. The main participants in the game are the government, electricity consuming enterprises, traditional power generators, and new energy power generators. The game model will be simulated using system dynamics, and recommendations and measures will be proposed. The findings indicate that: (1) the government’s ultimate strategy is to “act” when the losses resulting from government inaction exceed the gains from government action. (2) Behavioral evolution is consistent when market participants refrain from adjusting their cost inputs in response to fluctuations in market prices. (3) The market price is not as high as possible, but too high a price inhibits emission reduction. The behavioral evolution of carbon emission reduction in multiple markets is revealed in this study, which is of great importance in the promotion of carbon emission reduction. [ABSTRACT FROM AUTHOR]

This article presents an analytical design approach for the inner and outer rotor Permanent Magnet Synchronous Generators (PMSGs) that are a key component of wind turbines. By developing the analytical model, sensitivity analysis has been performed to determine the effect of some important geometrical and electromagnetic parameters on the generator's output characteristics. The GA optimization algorithm was used to find optimized designs in terms of efficiency, weight, cost, and temperature rise. In order to find the global optimization solution within the allowed variable range and in accordance with the constraints, a combined objective function has also been defined. In order to validate the analytical model, ANSYS electromagnetic and thermal simulations have been used. With this approach, the designer is provided with a good understanding of the input parameters and constraints in light of the application requirements. [ABSTRACT FROM AUTHOR]

Confidentiality of secret information is one of the mandatory issue of digitally modernized era of science and technology. Due to availability of several online web applications and social media usages nowadays, information is transmitted with ease. The privacy of these digital information can be addressed by using different encryption mechanisms. We have proposed digital information privacy preserving scheme based on three-dimensional chaotic self-exciting single disk homopolar system. Moreover, we have designed a circuit implementations of three-dimensional chaotic self-exciting single disk homopolar dynamical system. The suggested encryption scheme is tested against different security performance analyses which clearly reflects the affectedness of our encryption scheme. [ABSTRACT FROM AUTHOR]

[Display omitted] Moist-electric generators (MEGs), which are capable of spontaneously generating energy from ubiquitous moisture, are considered as a potential power supply candidate for wearable electronics. However, the application of the MEGs in the wearable field is still challenging due to the low electric output and the lack of wearable attributes such as breathability and flame retardancy. Herein, we demonstrated a wearable MEG with high power-output, breathability and flame retardancy, which was fabricated by designing an asymmetrical nanofiber assembly using hydrophilic polyvinyl alcohol/phytic acid (PVA/PA) and hydrophobic polyvinylidene difluoride (PVDF) nanofiber membranes. Owing to the synergistic effects of strong water absorption, enhanced ion release and numerous micro-nano transport channels, a single MEG of 1 cm2 could constantly generate high direct-current (DC) power, i.e., a voltage of 1.0 V, a current of 15.5 μA, and a power density of 3.0 μW cm−2, outperforming other reported nanofiber-based MEGs. More importantly, the asymmetric nanofiber structure ensured the moisture circulation inside MEG and thus produced a sustained voltage output for 7 days without any deterioration. The MEG also showed good flexibility, air/moisture permeability and flame retardancy, which give it necessary wearable attributes. Furthermore, large-scale integration of MEG units could be readily realized to fabricate a power source device for driving different portable electronics, while the moisture sensitivity made the MEG well used for sensing applications (e.g., respiration monitoring, fire warning). [ABSTRACT FROM AUTHOR]

This paper investigates the benefits and challenges of the multi‐MW direct‐drive offshore wind Vernier generators. It is worth noting that the comparison of generator topologies presented in ref. [1] was for the same power level and therefore a reduced machine volume for the surface‐mounted permanent magnet Vernier (SPM‐V) generators. This would mainly impact the capital expenditure (CAPEX) cost between the different investigated machines. Whereas in this paper, the performance is compared for the same machine volume that allows the Vernier generators to produce a much higher energy yield than a conventional SPM generator. As the extra energy yield would be beneficial over the lifetime of the turbine, this will have a bigger impact than the CAPEX cost savings with a reduced machine volume. In addition, a novel Vernier machine with magnets on both the stator and rotor has been proposed to further improve the energy yield. In addition to the basic electromagnetic performance, the levelised cost of energy (LCOE) of the three generator topologies, that is, the conventional SPM, SPM‐V and the proposed Vernier machines, has been compared. The direct‐drive powertrain systems with SPM‐V and the proposed Vernier generators can achieve LCOE of 12.3% and 24% lower than that of the conventional SPM generators, indicating their huge potential as an alternative to reduce the overall cost of energy. [ABSTRACT FROM AUTHOR]

Using observations from dual‐spacecraft (dual‐SC, Swarm A and C) and simulations from the Thermosphere‐Ionosphere Electrodynamics General Circulation Model (TIEGCM), this work investigates the ionospheric radial current (IRC) in response to subauroral polarization streams (SAPS) during the geomagnetic storm on 23 April 2023. At noon, a radially inward disturbance IRC (ΔIRC) emerges in response to SAPS, leading to a further intensification of inward IRC. The model simulation indicates that the dynamo current prevails over the polarization current, serving as the primary driver of the inward ΔIRC. Additionally, the significantly enhanced Pedersen conductivity potentially amplifies the inward ΔIRC. At dusk, ΔIRC exhibit a slight outward trend before 21 UT and a pronounced inward trend around 21–24 UT. This temporal variation is attributed to the equatorward propagation of SAPS‐induced thermospheric winds within 3–4 hr. The noontime inward electric field at the dip equator arises from both equatorward winds at low‐mid latitudes and local eastward winds. However, at dusk, the inward polarization electric field primarily stems from local disturbed eastward winds. Key Points: SAPS induce an inward ΔIRC at noon and triggers a slight outward ΔIRC followed by a substantial inward ΔIRC at duskThe interplay between neutral wind dynamo current and polarization current determines the direction of ΔIRCThe local eastward wind contributes to the inward electric field around noon and dusk [ABSTRACT FROM AUTHOR]

This paper concentrates on the efficient power outage solution in Nigeria University laboratories using Micro- controller based portable Solar Generator. The design specification include the System Capacity 1000Volts Ampere, modified Sine wave alternating current power, Output Voltage: 220-240 Volts, Output Frequency: 50Hz, battery Bank Capacity: 12Volts/40Ampere-hour, Solar Panel Specification: 30Watts, Pulse width modulator charge controller. During the design a voltage level of 5Volts was fed from preamplifier to the switching Metallic Oxide Silicon Field Effect Transistor that produces the gate current of 0.05 Ampere: Result showed that the oscillator rated output of 5v was obtained at pins 11 and 14 to switch the transistor. Result also showed that the frequency of the oscillator was adjusted and measured until standard frequency of 50Hz was achieved, for the MOSFETs operating at 50Hz and the period of the switching was 0.02sec. The transformer secondary voltage was measured and it gave the expected output of 230v. [ABSTRACT FROM AUTHOR]

The aim of this contribution is to present a segmentation method for the identification of voluntary movements from inertial data acquired through a single inertial measurement unit placed on the subject's wrist. Inertial data were recorded from 25 healthy subjects while performing 75 consecutive reach-to-grasp movements. The approach herein presented, called DynAMoS, is based on an adaptive thresholding step on the angular velocity norm, followed by a statistics-based post-processing on the movement duration distribution. Post-processing aims at reducing the number of erroneous transitions in the movement segmentation. We assessed the segmentation quality of this method using a stereophotogrammetric system as the gold standard. Two popular methods already presented in the literature were compared to DynAMoS in terms of the number of movements identified, onset and offset mean absolute errors, and movement duration. Moreover, we analyzed the sub-phase durations of the drinking movement to further characterize the task. The results show that the proposed method performs significantly better than the two state-of-the-art approaches (i.e., percentage of erroneous movements = 3%; onset and offset mean absolute error < 0.08 s), suggesting that DynAMoS could make more effective home monitoring applications for assessing the motion improvements of patients following domicile rehabilitation protocols. [ABSTRACT FROM AUTHOR]

Radiogenic heat production is fundamental to the energy budget of planets. Roughly half of the heat that Earth loses through its surface today comes from the three long-lived, heat-producing elements (potassium, thorium, and uranium). These three elements have long been believed to be highly lithophile and thus concentrate in the mantle of rocky planets. However, our study shows that they all become siderophile under the pressure and temperature conditions relevant to the core formation of large rocky planets dubbed super-Earths. Mantle convection in super-Earths is then primarily driven by heating from the core rather than by a mix of internal heating and cooling from above as in Earth. Partitioning these sources of radiogenic heat into the core remarkably increases the core-mantle boundary (CMB) temperature and the total heat flow across the CMB in super-Earths. Consequently, super-Earths are likely to host long-lived volcanism and strong magnetic dynamos. [ABSTRACT FROM AUTHOR]

Ultramassive white dwarfs with masses |$M\gtrsim 1.1\, {\rm M}_{\odot }$| probe extreme physics near the Chandrasekhar limit. Despite the rapid increase in observations, it is still unclear how many harbour carbon–oxygen (CO) versus oxygen–neon (ONe) cores. The origin of these white dwarfs and their strong magnetic fields – single stellar evolution or a stellar merger – is another open question. The steep mass–radius relation of the relativistic ultramassive white dwarfs shortens their crystallization time |$t_{\rm cryst}$|⁠ , such that the recently proposed crystallization dynamo mechanism may present an alternative to mergers in explaining the early appearance of magnetism in the observed population. However, the magnetic diffusion time from the convective dynamo to the white dwarf's surface delays the magnetic field's breakout time |$t_{\rm break}\gt t_{\rm cryst}$|⁠. We compute |$t_{\rm break}(M)$| for CO and ONe ultramassive white dwarfs and compare it to the local 40 pc volume-limited sample. We find that the breakout time from CO cores is too long to account for the observations. ONe crystallization dynamos remain a viable option, but their surrounding non-convective envelopes comprise only a few per cent of the total mass, such that |$t_{\rm break}$| is highly sensitive to the details of stellar evolution. [ABSTRACT FROM AUTHOR]

A model of a conducting cylinder with a radial temperature gradient which creates an electric field that increases with time in the surrounding vacuum is examined. The conditions under which this model functions are pointed out. An electric field is also generated when a magnetic field exists along the axis of the cylinder. This article discusses the interactions of the thermal flux, magnetic field, and charge distribution. Four models are considered with different conditions for the supply of electrons from a central source and the possibility either of capturing electrons inside the cylinder or their freely leaving it through the outer boundary. [ABSTRACT FROM AUTHOR]

In this study, discrete event time-variant parameter of a lumped SISO dynamical system is obtained for a novel energy harvester. The harvester utilizes the resonance vibration of a coupled fluid-mechanic system, which is comprised of a reciprocating-piston, a tunable oscillator and twin electric turbine generators. The system model is simplified by an underdamped spring-mass-damper with tunable parameters subjected to periodic or arbitrary impulse forces. We developed a method that solves general problems underlining non-homogenous ordinary second order differential equation with discrete event time-variant parameters. The method uses the superposition to compile the general solution by segmenting the problem into ODE equations with constant coefficient. Each segment corresponds to a change in system, and it is solved analytically with recursively updated initial conditions. We utilized this method to tune the system's natural frequency such that the accumulated energy is maximum within desired time range. We obtained the general solution of the displacement response due to varying parameters and input impulse force. We obtained the displacement peaks and their time of occurrence that could help understand the structural design limitation. We showed system displacement responses (constructive and destructive) corresponding to various impulse repetition patterns. We derived the relationship between energy, volume displacement, and volumetric flow rate (or piston velocity) and provided illustrative case studies. One finding shows that for a given impulse condition the accumulative energy exhibits local maximum and minimum within a narrow band of natural frequency range. The simulations showed the feasibility of generating considerable power from electric turbine when the air flow is driven by a resonating piston. [ABSTRACT FROM AUTHOR]

The research aims to identify the financial feasibility of cultivating the wheat crop under modern irrigation systems in desert areas and to clarify the impact of the capacity of the systems in those projects in achieving the financial feasibility of their establishment, using the economic evaluation criteria for the projects. The research included a study of 60 projects in Anbar Governorate for the 2020-2021 production season. It has been shown that projects that use several systems, despite their high investment costs, can recover the money invested in them within a relatively short period. The projects that use modern irrigation systems covering 60 donums were among the best projects that achieved technical efficiency in the productivity of the wheat crop, and the average net income reached the cash in the sample is about 1.3 billion dinars, while the average net income per donum in the research sample is about 189 thousand dinars. The sample was not able to achieve accounting profits, The research recommended the need to use electric power systems as an alternative to relying on electric power generators, as the average price of solar power systems in the Iraqi market is currently within reach. [ABSTRACT FROM AUTHOR]

Revit is a widely used architectural design and model creation software, but its control and performance of terrainhas been carried out in a "surface" way, not a real solid model, so it is difficult to meet the needs of some projects on terrain.Aiming at the pain point that internal functions of Revit cannot build 3D terrain entities, this paper takes forward designapplication of actual engineering projects as the research background, conducts research on solid terrain modeling of Revitbased on Dynamo, introduces five application methods, and proposes a optimization method to solve problems in practicalapplication, and finally forms a feasible solution. It provides some ideas for creating and using solid terrain models in Revitconveniently and quickly [ABSTRACT FROM AUTHOR]

Modelling and controlling an electrical Power Generation System (PGS), which consists of an Internal Combustion Engine (ICE) linked to an electric generator, poses a significant challenge due to various factors. These include the non-linear characteristics of the system's components, thermal effects, mechanical vibrations, electrical noise, and the dynamic and transient impacts of electrical loads. In this study, we introduce a fuzzy modelling identification approach utilizing the Takagi–Sugeno (T–S) structure, wherein model and control parameters are optimized. This methodology circumvents the need for deriving a mathematical model through energy balance considerations involving thermodynamics and the non-linear representation of the electric generator. Initially, a non-linear mathematical model for the electrical power system is obtained through the fuzzy c-means algorithm, which handles both premises and consequents in state space, utilizing input–output experimental data. Subsequently, the Particle Swarm Algorithm (PSO) is employed for optimizing the fuzzy parameter m of the c-means algorithm during the modelling phase. Additionally, in the design of the Parallel Distributed Compensation Controller (PDC), the optimization of parameters pertaining to the poles of the closed-loop response is conducted also by using the PSO method. Ultimately, numerical simulations are conducted, adjusting the power consumption of an inductive load. [ABSTRACT FROM AUTHOR]

A toroidal-topology traveling-wave thermoacoustic electric generator (TWTEG) is developed. It consists of a traveling-wave thermoacoustic engine, two linear alternators connected in parallel, and sets of variable resistive-capacitive (R-C) external electric loads, in conjunction with accessories and instrumentation required for experimental investigations. The working medium is helium with a static absolute pressure that varies from 25 bars to 30 bars. A detailed description of the thermal design of the heat exchangers is presented. Sustainable operation of the TWTEG is achieved over a range of external R-C loads at different imposed hot-side temperatures and mean gas pressures. The performance parameters are measured for different experimental conditions and compared with a developed lumped-element model. The comparison between the experimental results and predictions reveals a good agreement. The impedance matching between the thermoacoustic engine and the linear alternators is investigated experimentally over a wide range of external R-C loads. The external R-C loads play a crucial role in the operation of the TWTEG. The mean gas pressure changes the operating frequency; however, it has no significant influence on the operating range of the TWTEG on the R-C load map. Increasing the hot-side temperature improves the thermal-to-acoustic efficiency and extends the operating region into larger regions. [ABSTRACT FROM AUTHOR]

Mobile repair vehicles play an indispensable role on the battlefield and are increasingly being improved to enhance their effectiveness. When moving to repair locations on the battlefield, they often tow trailers, which include power generator sets. In some cases, these generator sets are replaced by trailers to transport ammunition or carry wounded soldiers. The article proposes improvements to the suspension system on the generator trailers and discusses the impact of vehicle speed and random road roughness on the movement of the mobile repair vehicle-trailer combination before and after the improvements. A dynamic model of the multi-body system is constructed, with the towing vehicle being a three-axle truck. The random roughness profile of the road surface is determined from simulation results based on ISO 8068 standards. The equations of motion are established using Lagrange's method and solved through simulation using Matlab software. The results of the article indicate the oscillation of the mobile repair vehicle-trailer combination when traveling at speeds of 36 km/h and 54 km/h on road surfaces with random roughness levels of class D and class E. After the improvement of the suspension system on the generator trailers, smoother trailer motion is observed. The study has shown that the vertical oscillation amplitude of the trailer decreased by up to 18 %, while the oscillation speed decreased by as much as 40 %. The findings provide a basis for further improving the suspension system on generator trailers to minimize oscillations, which is crucial for replacing generator trailers with specialized trailers for transporting ammunition or wounded soldiers on the battlefield. This is a significant issue in the field of national security and defense. [ABSTRACT FROM AUTHOR]

The objective of this paper is to reproduce and predict the series of solar cycle amplitudes using a simple time-series model that takes into account the variable time scale of the Gleissberg oscillation and the absence of clear evidence for odd–even alternation prior to Solar Cycle 9 (SC9). It is demonstrated that the Gleissberg oscillation can be quite satisfactorily modelled as a sinusoidal variation of constant amplitude with a period increasing linearly with time. Subtracting this model from the actual cycle amplitudes, a clear even–odd alternating pattern is discerned in the time series of the residuals since SC9. For this period of time, the mean value of the residuals for odd-numbered cycles is shown to exceed the value for even-numbered cycles by more than 4 σ , providing the clearest evidence yet for a persistent odd–even–odd alternation in cycle amplitudes. Random deviations from these means are less than half the standard deviation of the raw cycle amplitude time series for the same period, which allows the use of these regularities for solar cycle prediction with substantially better confidence than the simple climatological average. Predicted cycle amplitudes are found to be robust against the addition or omission of some data points from the input set, and the method correctly hindcasts SC23 and SC24. The potential physical background of the regularities is also discussed. Our predictions for the amplitudes of SC25, SC26, and SC27 are 155.8 ± 20.7 , 96.9 ± 25.1 and 140.8 ± 20.7 , respectively. This suggests that the amplitude of SC26 will be even lower than that of SC24, making it the weakest cycle since the Dalton Minimum. [ABSTRACT FROM AUTHOR]

Stimulus electro-responsive polymer materials can reversibly change their physical or chemical properties under various external stimuli such as temperature, light, force, humidity, pH, and magnetic fields. This review introduces typical conventional stimulus electro-responsive polymer materials and extensively explores novel directions in the field, including multi-stimuli electro-responsive polymer materials and humidity electro-responsive polymer materials pioneered by our research group. Despite significant advancements in stimulus electro-responsive polymer materials, ongoing research focuses on enhancing their efficiency, lifespan, and production costs. Interdisciplinary collaboration and advanced technologies promise to broaden the application scope of these materials, particularly in medical and environmental protection fields, ultimately benefiting society. [ABSTRACT FROM AUTHOR]

Sensor-based monitoring of process and tool condition in milling is a key technology for improving productivity and workpiece quality, as well as enabling automation of machine tools. However, industrial implementation of such monitoring systems remains a difficult task, since they require high sensitivity and minimal impact on CNC machines and cutting conditions. This paper presents a novel multi-sensory tool holder for measurement of process forces and vibrations in direct proximity to the cutting tool. In particular, the sensor system has an integrated temperature sensor, a triaxial accelerometer and strain gauges for measurement of axial force and bending moment. It is equipped with a self-sufficient electric generator and wireless data transmission, allowing for a tool holder design without interfering contours. Milling and drilling experiments with varying cutting parameters are conducted. The measurement data are analyzed, pre-processed and verified with reference signals. Furthermore, the suitability of all integrated sensors for detection of dynamic instabilities (chatter) is investigated, showing that bending moment and tangential acceleration signals are the most sensitive regarding this monitoring task. [ABSTRACT FROM AUTHOR]